AUTOMATIC CLEANING DEVICE

Abstract

 An automatic cleaning device, comprising: a moving platform (100) configured to automatically move on an operation surface; and a cleaning module (150) provided on the moving platform (100) and comprising a dry cleaning module (151) and a wet cleaning module (400). The wet cleaning module (400) comprises a cleaning head (410) used for cleaning the operation surface, and a driving unit (420) used for driving the cleaning head (410) to reciprocate along a target surface; the target surface is a part of the operation surface; the moving platform (100) is provided with a protruding pin (1001); the wet cleaning module (400) is provided with a groove (4001) matching the protruding pin (1001) to limit the working position of the wet cleaning module (400). The protruding pin can move directionally along the groove, so that a lifting/lowering module does not deviate in a lifting/lowering process.

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to Chinese Patent Applications No. 202120375468.4 and No. 202120375397.8, filed on February 10, 2021, which are incorporated herein by reference in their entireties as a part of the present disclosure.

TECHNICAL FIELD

[0002] The present disclosure relates to the field of cleaning robot technology, in particular to an automatic cleaning device.

BACKGROUND

[0003] At present, there are mainly two types of cleaning robots, that is, a sweeping robot and a mopping robot. The sweeping robot or the mopping robot has a single function, and may be used for sweeping or mopping only. If it is desired to carry out the sweeping and mopping at the same time, two devices have to be prepared, occupying double space and affecting the arrangement of other components due to the unreasonable design of structures.

[0004] In the prior art, a mopping module of the cleaning robot includes a lifting module, which can lift or lower the mopping module according to needs. However, during a lifting and lowering process of the mopping module, an offset of the lifting module would occur sometimes due to inherent reasons of the mechanical structure. As a result, the lifting module cannot completely arrive at a lifting position when it is lifted, which will affect the movement after lifting, thereby affecting the service life of the mopping module.

SUMMARY

[0005] An objective of the present disclosure is to provide an automatic cleaning device, which can solve one of the above technical problems. The specific solutions are described below.

[0006] According to embodiments of the present disclosure, an automatic cleaning device is provided, and the automatic cleaning device includes:

a mobile platform 100 configured to move automatically on an operating surface; and

a cleaning module 150 arranged on the mobile platform 100, and including:

a dry cleaning module 151 configured to clean at least a part of the operating surface by means of dry cleaning; and

a wet cleaning module 400 configured to clean at least a part of the operating surface by means of wet cleaning, wherein the wet cleaning module 400 includes:

a cleaning head 410 for cleaning the operating surface, and,

a driving unit 420 for driving the cleaning head 410 to make a reciprocating movement along a target surface, the target surface being a part of the operating surface,

wherein the mobile platform 100 is provided with a thimble 1001, and the wet cleaning module 400 is provided with a slot 4001 matched with the thimble 1001 for limiting a working position of the wet cleaning module 400.

[0007] In some embodiments, the slot 4001 includes an elastic element 40011, and the elastic element 40011 extends from the slot 4001 toward the mobile platform 100

[0008] In some embodiments, the slot 4001 further includes a thimble sheath 40012, and the thimble sheath 40012 extends upward from a bottom of the slot 4001, allowing the thimble 1001 to make a telescopic movement within the thimble sheath 40012.

[0009] In some embodiments, the elastic element 40011 is a helical spring, and the helical spring is arranged around the periphery of the thimble sheath 40012.

[0010] In some embodiments, the thimble 1001 includes a sliding portion 10011 and a fixed portion 10012, the sliding portion 10011 slides along the thimble sheath 40012, and the fixed portion 10012 is fixed to the mobile platform 100.

[0011] In some embodiments, the fixed portion 10012 includes a thread structure, and is fixed to the mobile platform 100 through the thread structure.

[0012] In some embodiments, an inner diameter of the thimble sheath 40012 is slightly larger than an outer diameter of the sliding portion 10011.

[0013] In some embodiments, a height of the elastic element 40011 in a natural state is greater than a height of the thimble sheath 40012.

[0014] In some embodiments, the wet cleaning module 400 further includes a driving platform 421 connected to a bottom surface of the mobile platform 100, and the slot 4001 is arranged on the driving platform 421.

[0015] In some embodiments, the slot 4001 is cylindrical or square.

[0016] Furthermore, according to embodiments of the present disclosure, an automatic cleaning device is provided, and the automatic cleaning device includes:

a mobile platform 100 configured to move automatically on an operating surface; and

a cleaning module 150 arranged on the mobile platform 100, and including:

a dry cleaning module 151 configured to clean at least a part of the operating surface by means of dry cleaning, and a wet cleaning module 400 configured to clean at least a part of the operating surface by means of wet cleaning,

wherein the wet cleaning module 400 includes a cleaning head 410 for cleaning the operating surface, a driving unit 420 for driving the cleaning head 410 to make a reciprocating movement along a target surface, the target surface being a part of the operating surface, and a driving platform 421 connected to a bottom surface of the mobile platform 100 for providing a driving force, wherein the driving platform 421 includes:

a motor 4211 arranged on a side of the driving platform 421 close to the mobile platform 100, for outputting power through an output shaft 42111 of the motor; and

a connection rod 4214 arranged on a side of the driving platform 421 opposite to the motor 4211, one end of the connection rod 4214 being connected to the output shaft 42111 of the motor, wherein a buffer clip 42112 is provided at a joint between the connection rod 4214 and the output the shaft 42111 of the motor.

[0017] In some embodiments, an end of the output shaft 42111 of the motor includes an annular groove 42113, and the buffer clip 42112 is snapped into the annular groove 42113.

[0018] In some embodiments, the buffer clip 42112 includes a notch 42114 for providing an entrance when the buffer clip 42112 is snapped into the annular groove 42113.

[0019] In some embodiments, the buffer clip 42112 further includes a snapping surface 42115 for clasping the annular groove 42113 tightly when the buffer clip 42112 is snapped into the annular groove 42113.

[0020] In some embodiments, the snapping surface 42115 is a continuous structure or an intermittent structure.

[0021] In some embodiments, the buffer clip 42112 is a sheet structure.

[0022] In some embodiments, one end of the connection rod 4214 is provided with an opening 42116, and the output shaft 42111 of the motor protrudes from the opening 42116 and is snapped by the buffer clip 42112.

[0023] In some embodiments, the driving platform 421 further includes a vibration member 4213 connected to the connection rod 4214, to make an approximate reciprocating movement under the driving of the motor 4211.

[0024] In some embodiments, an extending direction of the vibration member 4213 is substantially perpendicular to an extending direction of the connection rod 4214.

[0025] In some embodiments, the driving platform 421 further includes a vibration buffer unit 4215 arranged on the connection rod 4214.

[0026] Compared to the prior art, embodiments of the present disclosure provide the following technical effects.

[0027] The present disclosure provides an automatic cleaning device. A slot is provided on the wet cleaning module, a spring is provided inside the slot, and a thimble corresponding to the slot is provided on the mobile platform, so that the thimble can move directionally along the slot, and during the lifting and lowering of the lifting module, the slot and the thimble play the role of a position limit, so as to avoid deviation of the lifting module. The spring can reduce the vibration of the pallet caused by the falling state of the lifting module.

[0028] Furthermore, the present disclosure provides an automatic cleaning device. A buffer clip is provided at a joint between the connection rod of the wet cleaning module and the motor output shaft. When the mopping module encounters ground fluctuations or obstacles during the mopping process, the vibration damage to the motor caused by the displacement in the vertical direction can be reduced, thereby reducing the damage to the reliability of the overall structure and improving the service life of the mopping module.

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings herein, which are incorporated in and constitute a portion of this specification, illustrate embodiments consistent with the present disclosure and serve together with the specification to explain principles of the present disclosure. It is apparent that the drawings in the following description are only some embodiments of the present disclosure, and other drawings can be obtained based on the drawings by those of ordinary skill in the art without creative effort, in which:

FIG. 1 is an oblique view of an automatic cleaning device according to embodiments of the present disclosure.

FIG. 2 is a schematic diagram of a bottom structure of an automatic cleaning device according to embodiments of the present disclosure.

FIG. 3 is an oblique view of a driving wheel assembly on a side according to embodiments of the present disclosure.

FIG. 4 is a front view of a driving wheel assembly on a side according to embodiments of the present disclosure.

FIG. 5 is an oblique view of a dust box according to embodiments of the present disclosure.

FIG. 6 is an oblique view of a fan according to embodiments of the present disclosure.

FIG. 7 is a schematic diagram of a dust box in an open state according to embodiments of the present disclosure.

FIG. 8 is a schematic diagram of a dust box and a fan in an assembled state according to embodiments of the present disclosure.

FIG. 9 is an exploded view of an automatic cleaning device according to embodiments of the present disclosure.

FIG. 10 is a structural diagram of a supporting platform of an automatic cleaning device according to embodiments of the present disclosure.

FIG. 11 is a structural diagram of a vibration member of an automatic cleaning device according to embodiments of the present disclosure.

FIG. 12 is a schematic diagram of a cleaning head driving mechanism based on a crank slider mechanism according to embodiments of the present disclosure.

FIG. 13 is a schematic diagram of a cleaning head driving mechanism based on a double-crank mechanism according to embodiments of the present disclosure.

FIG. 14 is a schematic diagram of a cleaning head driving mechanism based on a crank mechanism according to embodiments of the present disclosure.

FIG. 15 is a structural diagram of a vibration member according to embodiments of the present disclosure.

FIG. 16 is a schematic diagram of an assembled structure of a cleaning substrate according to embodiments of the present disclosure.

FIG. 17 is a structural diagram of a clean water pump driven by a motor according to embodiments of the present disclosure.

FIG. 18 is a structural diagram of a lifting module driven by a motor according to embodiments of the present disclosure.

FIG. 19 is a schematic diagram of a lifting state of an automatic cleaning device according to embodiments of the present disclosure.

FIG. 20 is a schematic diagram of a lowering state of an automatic cleaning device according to embodiments of the present disclosure.

FIG. 21 is a schematic diagram of a lifting state of a four-link lifting structure according to embodiments of the present disclosure.

FIG. 22 is a schematic diagram of a lowering state of a four-link lifting structure according to embodiments of the present disclosure.

FIG. 23 is a schematic structural diagram of a dry cleaning module in a lowering state according to embodiments of the present disclosure.

FIG. 24 is a schematic structural diagram of a dry cleaning module in a lifting state according to embodiments of the present disclosure.

FIG. 25 is a schematic diagram of an overall structure of a thimble structure according to embodiments of the present disclosure.

FIG. 26 is a schematic diagram of an enlarged structure of a thimble structure according to embodiments of the present disclosure.

FIG. 27 is a schematic diagram of an exploded structure of a thimble structure according to embodiments of the present disclosure.

FIG. 28 is a schematic diagram of an enlarged structure at A in FIG. 10 according to embodiments of the present disclosure.

FIG. 29 is a schematic structural diagram of a buffer clip according to embodiments of the present disclosure.

List of Reference Numerals:

[0030] 100-mobile platform, 110-rearward portion, 111-forward portion, 120-detection system, 121-position determination unit, 122-buffer, 123-cliff sensor, 130-control system, 140-driving system, 141-driving wheel assembly, 142-steering assembly, 143-elastic element, 146-driving motor, 150-cleaning module, 151-dry cleaning module, 152-dust box, 153-filter screen, 154-dust suction inlet, 155-air outlet, 156-fan, 160-energy system, 170-human-machine interaction system, 400-wet cleaning module, 410-cleaning head, 420-driving unit, 421-driving platform, 422-supporting platform, 4211-motor, 4212-driving wheel, 4213-vibration member, 4214-connection rod, 4215-vibration buffering unit, 4216-pawl, 4218-clean water pump pipe, 4219-clean water pump, 4221-cleaning substrate, 4229-elastic detachable button, 4224-assembly region, 4225-engagement position, 4222-first sliding slot, 4223-second sliding slot, 525-first slider, 528-second slider, 512 (4227)-swiveling end, 514 (4226)-sliding end, 516 (624)-first pivot, 518 (626)-second pivot, 800 (600, 700)-driving mechanism, 500-four-link lifting structure, 501-first connection end, 502-second connection end, 5011-first bracket, 5012-first connection rod pair, 50121-first connection rod, 50122-second connection rod, 42194-cable, 50131-cable motor terminal, 50132-cable bracket terminal, 50111-cross beam, 50112-sliding slot, 50113-snapping hole, 50114-first longitudinal beam, 50115-second longitudinal beam, 5021-second bracket, 5022-second connection rod pair, 50221-third connection rod, 50222-fourth connection rod, 600-floating lifting structure, 601-first fixed bracket, 602-second fixed bracket, 603-connection rod pair, 6031-first connection rod pair, 6032-second connection rod pair, 60311-first connection rod, 60312-second connection rod, 60321-third connection rod, 60322-fourth connection rod, 6011-first fixed part, and 6012-second fixed part.

DETAILED DESCRIPTION

[0031] To make the objectives, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below with reference to the accompanying drawings. It is obvious that the described embodiments are only some, but not all of the embodiments of the present disclosure. All other embodiments obtained by those of ordinary skills in the art without creative efforts based on the embodiments in the present disclosure are within the protection scope of the present disclosure.

[0032] The terms used in the embodiments of the present disclosure are for the purpose of describing particular embodiments only and are not intended to limit the present disclosure. The singular forms "a/an", "said" and "the" used in the embodiments of the present disclosure and the appended claims are intended to include the plural forms as well, unless otherwise indicated clearly in the context. The term "a plurality of" generally includes at least two.

[0033] It is to be understood that, the term "and/or" used herein only describes an association relationship between associated objects, and indicates that there may be three kinds of relationships. For example, A and/or B may indicate three cases: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character "/" herein generally indicates an "or" relationship between the contextual objects.

[0034] It is to be understood that, although the terms first, second, third, etc. may be used to describe in the embodiments of the present disclosure, these should not be limited to these terms. These terms are only used to distinguish. For example, "first" ... may also be referred to as "second" without departing from the scope of the embodiments of the present disclosure. Similarly, "second" ... may also be referred to as "first".

[0035] It is also to be noted that, the terms "including", "containing", or any other variants are intended to cover the nonexclusive inclusion, such that a commodity or device including a series of elements includes not only those elements, but also other elements not listed explicitly or elements inherent to such a commodity or device. Without more limitations, the element defined by the phrase "including a ..." does not exclude the existence of other same elements in the commodity or device including the element.

[0036] Embodiments of the present disclosure will be described in detail in the following with reference to the drawings.

Embodiment 1

[0037] FIGs. 1-2 are schematic structural diagrams of an automatic cleaning device according to some embodiments. As shown in FIGs. 1-2, the automatic cleaning device may be a vacuum suction robot, or may be a mopping/brushing robot, or may be a window climbing robot, or the like. The automatic cleaning device may include a mobile platform 100, a detection system 120, a control system 130, a driving system 140, a cleaning module 150, an energy system 160 and a human-machine interaction system 170.

[0038] The mobile platform 100 may be configured to move automatically along a target direction on an operating surface. The operating surface may be a surface to be cleaned by the automatic cleaning device. In some embodiments, the automatic cleaning device may be a mopping robot, and is operated on a ground, and then the ground is the operating surface. The automatic cleaning device may also be a window cleaning robot, and is operated on an outer surface of the glass of a building, and then the glass is the operating surface. The automatic cleaning device may also be a pipe cleaning robot, and is operated on an inner surface of a pipe, and then the inner surface of the pipe is the operating surface. For the purpose of explanation, the following description in the present disclosure takes a mopping robot as an example for illustration.

[0039] In some embodiments, the mobile platform 100 may be an autonomous mobile platform, or a non-autonomous mobile platform. The autonomous mobile platform means that the mobile platform 100 itself can automatically and adaptively make an operational decision based on an unexpected environmental input, and the non-autonomous mobile platform itself cannot adaptively make an operational decision based on the unexpected environmental input, but can execute a given procedure or operate according to a certain logic. Correspondingly, when the mobile platform 100 is the autonomous mobile platform, the target direction may be determined autonomously by the automatic cleaning device. When the mobile platform 100 is the non-autonomous mobile platform, the target direction may be set systematically or manually. When the mobile platform 100 is the autonomous mobile platform, the mobile platform 100 includes a forward portion 111 and a rearward portion 110.

[0040] The detection system 120 includes a position determination unit 121 located on the mobile platform 100, a buffer 122 located at the forward portion 111 of the mobile platform 100, a cliff sensor 123 and a sensing device, such as an ultrasonic sensor (not shown), an infrared sensor (not shown), a magnetometer (not shown), an accelerometer (not shown), a gyroscope (not shown), an odometer (not shown), and the like, located at a bottom of the mobile platform 100, for providing various position information and motion state information of the automatic cleaning device to the control system 130.

[0041] In order to describe behaviors of the automatic cleaning device more clearly, directions are defined as follows: the automatic cleaning device may travel on the ground by means of various combinations of movements relative to the following three mutually perpendicular axes defined by the mobile platform 100, i.e., a transversal axis X, a front and rear axis Y and a central vertical axis Z. A forward driving direction along the front and rear axis Y is designated as "forward", and a rearward driving direction along the front and rear axis Y is designated as "rearward". The transversal axis X substantially extends between a right wheel and a left wheel of the automatic cleaning device along a center of an axis defined by a center point of a driving wheel assembly 141. The automatic cleaning device may rotate around the axis X. It is referred to as "pitch up" when the forward portion of the automatic cleaning device is tilted upward and the rearward portion thereof is tilted downward, and it is referred to as "pitch down" when the forward portion of the automatic cleaning device is tilted downward and the rearward portion thereof is tilted upward. In addition, the automatic cleaning device may rotate around the axis Z. In a forward direction of the automatic cleaning device, it is referred to as "turn right" when the automatic cleaning device is tilted to the right of the axis Y, and it is referred to as "turn left" when the automatic cleaning device is tilted to the left of the axis Y.

[0042] As shown in FIG. 2, cliff sensors 123 are provided at the bottom of the mobile platform 100 and in front and rear of the driving wheel assembly 141, respectively, for preventing the automatic cleaning device from falling off when the automatic cleaning device retreats, so as to avoid the damage to the automatic cleaning device. The aforementioned "front" refers to a side that is the same as a travelling direction of the automatic cleaning device, and the aforementioned "rear" refers to a side that is opposite to the travelling direction of the automatic cleaning device.

[0043] The position determination unit 121 includes, but is not limited to, a camera and a laser distance sensor (LDS).

[0044] Components in the detection system 120 may operate independently, or operate together to achieve a target function more accurately. The surface to be cleaned is identified through the cliff sensors 123 and the ultrasonic sensor to determine physical properties of the surface to be cleaned, including a surface material, a degree of cleanliness, and the like, and may be determined more accurately in combination with the camera, the LDS, or the like.

[0045] For example, the ultrasonic sensor may determine whether the surface to be cleaned is a carpet. If the ultrasonic sensor determines that the surface to be cleaned is made of a carpet material, the control system 130 controls the automatic cleaning device to perform cleaning in a carpet mode.

[0046] The forward portion 111 of the mobile platform 100 is provided with the buffer 122. During cleaning, when the driving wheel assembly 141 drives the automatic cleaning device to travel on the ground, the buffer 122 detects one or more events (or objects) in a travelling path of the automatic cleaning device via a sensor system, e.g., an infrared sensor, and the automatic cleaning device may control the driving wheel assembly 141 based on the event (or object), such as an obstacle or a wall, detected by the buffer 122, to enable the automatic cleaning device to respond to the event (or object), for example, to move away from the obstacle.

[0047] The control system 130 is disposed on a main circuit board in the mobile platform 100, and includes a computing processor such as a central processing unit and an application processor, that communicates with a non-transitory memory such as a hard disk, a flash memory and a random-access memory. The application processor is configured to receive environmental information sensed by the plurality of sensors and transmitted from the detection system 120, depict an instant map of an environment where the automatic cleaning device is located using a positioning algorithm, e.g., simultaneous localization and mapping (SLAM), based on obstacle information fed back by the LDS, and autonomously determine a travelling path based on the environmental information and the environmental map to control the driving system 140 to perform operations, such as travelling forward, travelling backward, and/or steering, based on the autonomously determined travelling path. In some embodiments, the control system 130 may also determine based on the environmental information and the environmental map whether to activate the cleaning module 150 to perform a cleaning operation.

[0048] In some embodiments, the control system 130 may, based on distance information and speed information which are fed back by the buffer 122, the cliff sensors 123, the ultrasonic sensor, the infrared sensor, the magnetometer, the accelerometer, the gyroscope, the odometer, and other sensing devices, comprehensively determine a current operation state of the sweeping robot. For example, the sweeping robot is crossing a doorsill, moving onto a carpet, standing at an edge of a cliff, being stuck at the top or bottom, having a full dust box or being picked up, and will also give specific next-step action strategies for different situations, so that the action of the automatic cleaning device is more in line with requirements of an owner and provides better user experience. The control system can plan the most efficient and reasonable sweeping path and sweeping mode based on the instant map depicted by the SLAM, thereby greatly improving the sweeping efficiency of the automatic cleaning device.

[0049] The driving system 140 may execute a driving command based on specific distance and angle information, such as x, y, and θ components, to manipulate the automatic cleaning device to travel across the ground. FIGs. 3 and 4 are respectively an oblique view and a front view of a driving wheel assembly 141 on a side according to embodiments of the present disclosure. As shown in the figures, the driving system 140 includes the driving wheel assembly 141, and may control a left wheel and a right wheel simultaneously. In order to control the movement of the automatic cleaning device more precisely, the driving system 140 preferably includes a left driving wheel assembly and a right driving wheel assembly. The left driving wheel assembly and the right driving wheel assembly are arranged symmetrically along a transversal axis defined by the mobile platform 100. The driving wheel assembly includes a body portion, a driving wheel and an elastic element. One end of the body portion is connected to a frame. The driving wheel is disposed in the body portion and is driven by a driving motor 146. The elastic element is connected between the body portion and the frame, and is configured to provide an elastic force between the frame and the body portion. The driving motor 146 is located outside the driving wheel assembly 141, a center of an axis of the driving motor 146 is located within a sectional projection of the driving wheel, and the driving wheel assembly 141 may also be connected to the odometer and a circuit for measuring driving current.

[0050] In order to enable the automatic cleaning device to move on the ground more stably or to have a stronger movement ability, the automatic cleaning device may include one or more steering assemblies 142. The steering assembly 142 may be a driven wheel, and may also be a driving wheel, which includes but is not limited to a universal wheel in view of a structures thereof. The steering assembly 142 may be located in front of the driving wheel assembly 141.

[0051] The driving motor 146 provides power for rotation of the driving wheel assembly 141 and/or the steering assembly 142.

[0052] The driving wheel assembly 141 may be detachably connected to the mobile platform 100 to facilitate assembling, disassembling and maintaining. The driving wheel may have an offset drop suspension system movably fastened, e.g., rotatably attached, to the mobile platform 100 of the automatic cleaning device, and maintain with a certain grounding force contact with the ground and traction through an elastic element 143, such as a tension spring or a compression spring. At the same time, the cleaning module 150 of the automatic cleaning device is also in contact with the surface to be cleaned with a certain pressure.

[0053] The energy system 160 includes a rechargeable battery, such as a nickel-hydride battery and a lithium battery. The rechargeable battery may be connected with a charging control circuit, a battery pack charging temperature detection circuit and a battery undervoltage monitoring circuit. The charging control circuit, the battery pack charging temperature detection circuit and the battery undervoltage monitoring circuit are then connected to a single-chip microcomputer control circuit. A host of the automatic cleaning device is connected to a charging station through a charging electrode disposed on a side of or below a body of the automatic cleaning device for charging.

[0054] The human-machine interaction system 170 includes buttons that are on a panel of the host and used by a user to select functions. The human-machine interaction system 170 may further include a display screen and/or an indicator light and/or a horn that present a current state or function item of the automatic cleaning device to the user. The human-machine interaction system 170 may further include a mobile client program. For a route navigation type cleaning device, a mobile client may present a map of the environment where the apparatus is located and a position of the apparatus to the user, which may provide richer and more user-friendly function items to the user.

[0055] The cleaning module 150 may include a dry cleaning module 151 and/or a wet cleaning module 400.

[0056] As shown in FIGs. 5-8, the dry cleaning module 151 includes a rolling brush, a dust box, a fan and an air outlet. The rolling brush having a certain interference with the ground sweeps up the garbage on the ground and rolls up the garbage to the front of a dust suction inlet between the rolling brush and the dust box. The garbage is then sucked into the dust box by air having a suction force, which is generated by the fan and passes through the dust box. A dust removal capacity of the sweeping robot may be characterized by a dust pickup efficiency (DPU) of the garbage. The DPU is affected by a structure and a material of the rolling brush, by a utilization rate of the air in an air channel formed by the dust suction inlet, the dust box, the fan, the air outlet and connecting components between the four, and by a type and a power of the fan, which is a complex systematic design problem. Compared to an ordinary plug-in vacuum cleaner, the improvement of the dust removal capacity is more meaningful for the automatic cleaning device with limited energy, because the improvement of the dust removal capacity directly and effectively reduces requirements for energy. That is, the cleaning device may sweep 80 square meters of the ground for one single charge before, and is evolved to sweep 180 square meters or more for one single charge. Furthermore, the service life of the battery with the reduced number of charging times will also be greatly increased, so that the frequency of replacing the battery by the user will also be decreased. More intuitively and importantly, the improvement of the dust removal capacity is the most obvious and important user experience, for the user will directly determine whether the thorough cleaning is achieved. The dry cleaning module may further include a side brush 152 having a rotary shaft at an angle relative to the ground, for moving debris into a rolling brush region in the cleaning module 150.

[0057] FIG. 5 is a schematic structural diagram of a dust box 152 in the dry cleaning module, FIG. 6 is a schematic structural diagram of a fan 156 in the dry cleaning module, FIG. 7 is a schematic diagram of the dust box 152 in an open state, and FIG. 8 is a schematic diagram of the dust box and the fan in an assembled state.

[0058] The rolling brush having a certain interference with the ground sweeps up the garbage on the ground and rolls up the garbage to the front of the dust suction inlet 154 between the rolling brush and the dust box 152, and then the garbage is sucked into the dust box 152 by a suction force from air which is generated by the fan 156 and passes through the dust box 152. The garbage is isolated, by a filter screen 153, inside the dust box 152 on a side close to the dust suction inlet 154, and the filter screen 153 completely isolates the dust suction inlet from the air outlet, so that the filtered air enters the fan 156 through the air outlet 155.

[0059] Typically, the dust suction inlet 154 of the dust box 152 is located in front of the automatic cleaning device, the air outlet 155 is located on a side of the dust box 152, and an air inlet of the fan 156 is communicated with the air outlet of the dust box.

[0060] A front panel of the dust box 152 may be opened for cleaning the garbage in the dust box 152.

[0061] The filter screen 153 is detachably connected to a body of the dust box 152 to facilitate assembling, disassembling and cleaning of the filter screen.

[0062] According to embodiments of the present disclosure, as shown in FIGs. 9-11, the wet cleaning module 400 according to the present disclosure is configured to clean at least a part of the operating surface by means of wet cleaning. The wet cleaning module 400 includes a cleaning head 410 and a driving unit 420. The cleaning head 410 is used for cleaning at least a part of the operating surface, and the driving unit 420 is used for driving the cleaning head 410 to make an approximate reciprocating movement along a target surface, the target surface being a part of the operating surface. The cleaning head 410 makes a reciprocating movement along the surface to be cleaned, a surface of the cleaning head 410 in contact with the surface to be cleaned is provided with a cleaning cloth or a cleaning plate, and a high-frequency friction with the surface to be cleaned occurs due to the reciprocating movement, thereby removing stains on the surface to be cleaned.

[0063] The higher the friction frequency is, the more friction occurring per unit time. A high-frequency reciprocating movement, also referred to as reciprocating vibration, has a much higher cleaning ability than an ordinary reciprocating movement, e.g., rotational friction cleaning. In some embodiments, when the friction frequency approaches a sound wave, a cleaning effect will be much higher than that of the rotational friction cleaning with dozens of revolutions per minute. On the other hand, tufts on the surface of the cleaning head are more uniform and extend in the same direction under the shaking of the high-frequency vibration, so as to achieve a more uniform overall cleaning effect, rather than being in the case of low-frequency rotation, where the cleaning effect can only be improved due to increased frictional force by applying a down pressure. Appling the down pressure only does not enable the tufts to extend approximately in the same direction. Therefore, in terms of the effect, water marks on the operating surface after being cleaned under the high-frequency vibration are more uniform without chaotic water stains.

[0064] The reciprocating movement may be a repeated motion along any one or more directions within the operating surface, or may be a vibrating motion perpendicular to the operating surface, which is not strictly limited. In some embodiments, the direction of the reciprocating movement of the cleaning module is substantially perpendicular to the travelling direction of the automatic cleaning device, because the direction of the reciprocating movement being parallel to the travelling direction of the automatic cleaning device may result instability in travelling of the automatic cleaning device itself due to thrust and resistance in the travelling direction, which makes it easy for the driving wheel to skid. The skid would be more obvious when the wet cleaning module is included, for the wetness of the operating surface increases the possibility of skid. The skid not only affects the stable travelling and cleaning of the automatic cleaning device, but also causes inaccurate distance measurements of the sensors such as the odometer and the gyroscope, thereby resulting inaccurate in locating and map drawing of a navigation type automatic cleaning device. In the case of frequent skid, the effect on the SLAM cannot be ignored. Therefore, it is necessary to avoid the skid of the automatic cleaning device as much as possible. In addition to the skid, a motion component of the cleaning head in the travelling direction of the automatic cleaning device causes the automatic cleaning device to be pushed forward and backward constantly during travelling, and thus the automatic cleaning device cannot travel stably and smoothly.

[0065] According to embodiments of the present disclosure, as shown in FIG. 9, the driving unit 420 includes a driving platform 421 connected to a bottom surface of the mobile platform 100, for providing a driving force, and a supporting platform 422 detachably connected to the driving platform 421, for supporting the cleaning head 410. The supporting platform 422 can be lifted and lowered under the driving of the driving platform 421.

[0066] According to embodiments of the present disclosure, a lifting module is provided between the cleaning module 150 and the mobile platform 100, so that the cleaning module 150 may be in better contact with the surface to be cleaned, or different cleaning strategies may be used for surfaces to be cleaned made of different materials.

[0067] In some embodiments, the dry cleaning module 151 may be connected to the mobile platform 100 through a passive lifting module. When the cleaning device encounters an obstacle, the dry cleaning module 151 may pass the obstacle more easily through the lifting module.

[0068] In some embodiments, the wet cleaning module 400 may be connected to the mobile platform 100 through an active lifting module. When the wet cleaning module 400 does not participate in the operation temporarily, or when a surface to be cleaned cannot be cleaned by using the wet cleaning module 400, the wet cleaning module 400 is lifted through the active lifting module and separated from the surface to be cleaned, so as to realize the change of cleaning means.

[0069] As shown in FIGs. 10-11, the driving platform 421 includes: a motor 4211 disposed on a side of the driving platform 421 close to the mobile platform 100 and for outputting power through a motor output shaft; a driving wheel 4212 connected to the motor output shaft and having an asymmetric structure; and a vibration member 4213 disposed on a side of the driving platform 421 opposite to the motor 4211 and connected to the driving wheel 4212 to make a reciprocating movement under the asymmetrical rotation of the driving wheel 4212.

[0070] The driving platform 421 may further include a gear mechanism. The gear mechanism may connect the motor 4211 and the driving wheel 4212. The motor 4211 may directly drive the driving wheel 4212 to swivel, or may indirectly drive the driving wheel 4212 to swivel through the gear mechanism. Those of ordinary skill in the art may understand that the gear mechanism may be one gear, or may be a gear set composed of a plurality of gears.

[0071] The motor 4211 simultaneously transmits, through a power transmission unit, power to the cleaning head 410, the driving platform 421, the supporting platform 422, a water delivery mechanism, a water tank, and the like. The energy system 160 provides power and energy for the motor 4211 and is entirely controlled by the control system 130. The power transmission unit may be a gear driving mechanism, a chain driving mechanism, a belt driving mechanism, or may be a worm gear, or the like.

[0072] The motor 4211 has a forward output mode and a reverse output mode. In the forward output mode, the motor 4211 rotates in a forward direction, and in the reverse output mode, the motor 4211 rotates in a reverse direction. In the forward output mode of the motor 4211, the motor 4211 drives, through the power transmission unit, the vibration member 4213 of the driving platform in the wet cleaning module 400 to make an approximate reciprocating movement and simultaneously drives the water delivery mechanism to move synchronously. In the reverse output mode of the motor 4211, the motor 4211 drives the driving platform 421 to be lifted and lowered through the power transmission unit.

[0073] In some embodiments, the driving platform 421 further includes a connection rod 4214 extending along an edge of the driving platform 421 and connecting the driving wheel 4212 and the vibration member 4213, so that the vibration member 4213 extends to a preset position. An extension direction of the vibration member 4213 is perpendicular to the connection rod 4214, so that a reciprocating movement direction of the vibration member 4213 is substantially perpendicular to the travelling direction of the automatic cleaning device.

[0074] The motor 4211 is connected to the driving wheel 4212, the vibration member 4213, the connection rod 4214 and a vibration buffering unit 4215 through the power transmission unit. The vibration member 4213 and the connection rod 4214 constitute an approximate L-shaped structure, as shown in FIG. 15. The vibration member 4213 makes a reciprocating movement under the driving of the connection rod 4214. The vibration buffering unit 4215 has functions of damping and reducing the shaking of a motion behavior driven by the driving wheel 4212, so that the vibration member 4213 may vibrate stably within a motion range provided by the supporting platform 422. In some embodiments, the vibration buffering unit 4215 is made of a soft material, optionally a rubber structure, and the vibration buffering unit 4215 is sleeved on the connection rod 4214. On the other hand, the vibration buffering unit 4215 may also protect the vibration member 4213 from being damaged due to the collision with the driving platform 421, and thus may also affect the reciprocating movement of the vibration member 4213. Movable components and fixed components of the driving platform 421 are restricted from moving in the travelling direction of the automatic cleaning device through connections with less elasticity, and are connected flexibly and allowed to move in the direction substantially perpendicular to the travelling direction, that is, in a vibration direction of the vibration member 4213. The above two movement restrictions allow the vibration member 4213 to make an approximate reciprocating movement rather than an accurate reciprocating movement. When the wet cleaning module 400 is activated, the motor 4211 starts to rotate forward to drive the connection rod 4214 through the driving wheel 4212 to make a reciprocating movement along the surface of the driving platform 421. At the same time, the vibration buffering unit 4215 drives the vibration member 4213 to make an approximate reciprocating movement along the surface of the driving platform 421, the vibration member 4213 drives a cleaning substrate 4221 to make an approximate reciprocating movement along the surface of the supporting platform 422, and the cleaning substrate 4221 drives a movable region 412 to make an approximate reciprocating movement along the surface to be cleaned. At this time, a clean water pump enables clean water to flow out of a clean water tank and sprinkles the clean water on the cleaning head 410 through a water discharging unit 4217, and the cleaning head 410 cleans the surface to be cleaned through the reciprocating movement.

[0075] The cleaning intensity/efficiency of the automatic cleaning device may also be automatically and dynamically adjusted according to an operation environment of the automatic cleaning device. For example, the automatic cleaning device may achieve a dynamic adjustment according to physical information of the surface to be cleaned detected by the detection system 120. For example, the detection system 120 may detect the flatness of the surface to be cleaned, the material of the surface to be cleaned, the existence of oil and dust, and other information, and transmit the information to the control system 130 of the automatic cleaning device. Correspondingly, the control system 130 may instruct the automatic cleaning device to automatically and dynamically adjust a rotational speed of the motor and a transmission ratio of the power transmission unit according to the operation environment of the automatic cleaning device, so as to adjust a preset reciprocating period of the reciprocating movement of the cleaning head 410.

[0076] For example, when the automatic cleaning device operates on a flat ground, the preset reciprocating period may be automatically and dynamically adjusted to be longer, and a water volume of the water pump may be automatically and dynamically adjusted to be smaller. When the automatic cleaning device operates on a less flat ground, the preset reciprocating period may be automatically and dynamically adjusted to be shorter, and the water volume of the water pump may be automatically and dynamically adjusted to be larger. This is because it is easier to clean the flat ground than the less flat ground, and thus a larger water volume and a reciprocating movement of the cleaning head 410 at a higher speed (i.e., a higher frequency) are needed for cleaning an uneven ground.

[0077] For another example, when the automatic cleaning device operates on a table, the preset reciprocating period may be automatically and dynamically adjusted to be longer, and the water volume of the water pump may be automatically and dynamically adjusted to be smaller. When the automatic cleaning device 100 operates on a ground, the preset reciprocating period may be automatically and dynamically adjusted to be shorter, and the water volume of the water pump may be automatically and dynamically adjusted to be larger. This is because the table has less dust and oil compared to the ground, and the material of the table is also easier to clean. Therefore, the table can be cleaned with fewer reciprocating movements of the cleaning head 410 and relatively smaller water volume of the water pump.

[0078] According to embodiments of the present disclosure, the supporting platform 422 includes a cleaning substrate 4221 which is movably disposed on the supporting platform 422, and the cleaning substrate 4221 makes an approximate reciprocating movement under the vibration of the vibration member 4213. In some embodiments, as shown in FIG. 16, the cleaning substrate 4221 includes an assembly notch 42211 which is disposed at a position in contact with the vibration member 4213. When the supporting platform 422 is connected to the driving platform 421, the vibration member 4213 is assembled to the assembly notch 42211, so that the cleaning substrate 4221 may make an approximate reciprocating movement synchronously along with the vibration member 4213. The cleaning substrate 4221 includes four first position limits 42212 in the travelling direction of the cleaning device, and the four first position limits 42212 are flexibly connected to the cleaning substrate 4221 with a small elastic scaling space, thereby limiting the movement of the cleaning substrate 4221 relative to the supporting platform 422 in the travelling direction of the cleaning device. The cleaning substrate 4221 includes two second position limits 42213 in a direction perpendicular to the travelling direction of the cleaning device, and the two second position limits 42213 limit a range of the reciprocating movement of the cleaning substrate 4221 in the direction perpendicular to the travelling direction of the cleaning device. Furthermore, a water discharging hole 42214 is provided near the assembly notch 42211 of the cleaning substrate 4221 to enable water to flow from the water discharging unit 4217 to the cleaning head 410 via the water discharging hole. The cleaning substrate 4221 makes an approximate reciprocating movement due to the influence of the position limits and the vibration buffering unit. The cleaning substrate 4221 is located at a portion of the supporting platform 422, and the vibration frequency may be made higher by means of local vibration, for example, reaching a frequency range of the sound wave. The movable components and the fixed components of the driving platform 421 are restricted from moving in the travelling direction of the automatic cleaning device through connections with less elasticity, and are connected flexibly and allowed to move in the direction substantially perpendicular to the travelling direction, that is, in the vibration direction of the vibration member 4213.

[0079] FIG. 12 shows another cleaning head driving mechanism 500 based on a crank slider mechanism according to embodiments of the present disclosure. The driving mechanism 500 may be applied to the driving platform 421. The driving mechanism 500 includes a driving wheel 4212, a vibration member 4213, a cleaning substrate 4221, a sliding slot 4222 (a first sliding slot) and a sliding slot 4223 (a second sliding slot).

[0080] The sliding slots 4222 and 4223 are formed in the supporting platform 422. Both ends of the cleaning substrate 4221 include a slider 525 (a first slider) and a slider 528 (a second slider), respectively. Each of the sliders 525 and 528 is a protrusion at each of both ends of the cleaning substrate 4221. The slider 525 is inserted into the sliding slot 4222 and may slide along the sliding slot 4222, and the slider 528 is inserted into the sliding slot 4223 and may slide along the sliding slot 4223. In some embodiments, the sliding slot 4222 and the sliding slot 4223 are on the same line. In some embodiments, the sliding slot 4222 and the sliding slot 4223 are not on the same line. In some embodiments, the sliding slot 4222 and the sliding slot 4223 extend along the same direction. In some embodiments, an extension direction of the sliding slot 4222 and an extension direction of the sliding slot 4223 are the same as that of the cleaning substrate 4221. In some embodiments, the extension direction of the sliding slot 4222 and the extension direction of the sliding slot 4223 are different from that of the cleaning substrate 4221. In some embodiments, the extension direction of the sliding slot 4222 is different from the extension direction of the sliding slot 4223. For example, as shown in FIG. 12, the extension direction of the sliding slot 4222 is the same as that of the cleaning substrate 4221, and the extension direction of the sliding slot 4223 is at a certain angle with that of the sliding slot 4222.

[0081] The vibration member 4213 includes a swiveling end 512 and a sliding end 514. The swiveling end 512 is connected to the driving wheel 4212 through a first pivot 516, and the sliding end 514 is connected to the cleaning substrate 4221 through a second pivot 518.

[0082] A swiveling center of the driving wheel 4212 is at a point O, and a pivoting center of the first pivot 516 is at a point A. The point O and the point A do not coincide, and a distance between the point O and the point A is a preset distance d.

[0083] When the driving wheel 4212 rotates, the point A also swivels along a circular path. The swiveling end 512 swivels along the circular path accordingly as the point A swivels. The sliding end 514 drives through the second pivot 518 the cleaning substrate 4221 to slide. The slider 525 of the cleaning substrate 4221 makes a linear reciprocating movement along the sliding slot 4222, and the slider 528 makes a linear reciprocating movement along the sliding slot 4223. In FIG. 4, a moving speed of the mobile platform 210 is V0, and a moving direction thereof is a target direction. According to some embodiments, when both the sliding slot 4223 and the sliding slot 4222 are approximately perpendicular to the direction of the moving speed V0 of the mobile platform 210, an overall displacement of the cleaning substrate 4221 is substantially perpendicular to the target direction. According to some embodiments, when any one of the sliding slot 4223 and the sliding slot 4222 forms an angle other than 90 degrees with the target direction, the overall displacement of the cleaning substrate 4221 includes both a component perpendicular to the target direction and a component parallel to the target direction.

[0084] In some embodiments, a vibration buffering unit 4215 is included, which is disposed on the connection rod 4214, for reducing vibration in a specific direction. In some embodiments, the vibration buffering unit 4215 is used for reducing the vibration in a direction of a movement component perpendicular to the target direction of the automatic cleaning device.

[0085] FIG. 13 shows another cleaning head driving mechanism 600 based on a double-crank mechanism according to embodiments of the present disclosure. The driving mechanism 600 may be applied to the driving platform 421. The driving mechanism 600 includes a driving wheel 4212 (a first driving wheel), a driving wheel 4212' (a second driving wheel) and a cleaning substrate 4221.

[0086] The cleaning substrate 4221 has two ends, a first end of the cleaning substrate 4221 is connected to the driving wheel 4212 through a pivot 624 (a first pivot), and a second end thereof is connected to the driving wheel 4212' through a pivot 626 (a second pivot). A swiveling center of the driving wheel 4212 is at a point O, and a pivoting center of the pivot 624 is at a point A. The point O and the point A do not coincide, and a distance between the point O and the point A is a preset distance d. A swiveling center of the driving wheel 236 is a point O', and a pivoting center of the pivot 626 is point A'. The point O' and the point A' do not coincide, and the distance between the point O' and the point A' is a preset distance d. In some embodiments, the point A, the point A', the point O, and the point O' are located on the same plane. Therefore, the driving wheel 4212, the driving wheel 4212' and the cleaning substrate 4221 may form a double-crank mechanism (or a parallelogram mechanism), among which, the cleaning substrate 4221 acts as a coupling lever, and the driving wheels 4212 and 4212' act as two cranks.

[0087] In some embodiments, a vibration buffering unit 4215 is included, which is disposed on the connection rod 4214, for reducing vibration in a specific direction. In some embodiments, the vibration buffering unit 4215 is used for reducing the vibration in a direction of a movement component perpendicular to the target direction of the automatic cleaning device.

[0088] FIG. 14 shows a cleaning head driving mechanism 700 based on a crank slider mechanism according to embodiments of the present disclosure. The driving mechanism 700 may be applied to the driving platform 421. The driving mechanism 700 includes a driving wheel 4212, a cleaning substrate 4221 and a sliding slot 4222.

[0089] The sliding slot 4222 is formed in the supporting platform 422. The cleaning substrate 4221 includes a swiveling end 4227 and a sliding end 4226. The swiveling end 4227 is connected to the driving wheel 4212 through a pivot 4228. A swiveling center of the driving wheel 4212 is at a point O, and a pivoting center of the pivot 4228 for the swiveling end is at a point A. The point O and the point A do not coincide, and a distance between the point O and the point A is a preset distance d. The sliding end 4226 includes a slider 4225. The slider 4225 is a protrusion on the sliding end 4226. The slider 4225 is inserted into the sliding slot 4222 and may slide along the sliding slot 4222. Therefore, the driving wheel 4212, the cleaning substrate 4221, the slider 4225 and the sliding slot 4222 constitute the crank slider mechanism.

[0090] When the driving wheel 4212 rotates, the point A swivels along a circular path. The swiveling end 4227 of the cleaning substrate 4221 swivels along the circular path accordingly as the point A swivels. The slider 4225 also slides in the sliding slot 4222 and makes a linear reciprocating movement. As a result, the cleaning substrate 4221 starts to make a reciprocating movement. According to some embodiments, the sliding slot 4222 is approximately perpendicular to a direction of the target direction of the moving speed of the mobile platform. Therefore, the linear motion of the sliding end 4226 includes a component perpendicular to the target direction, and the circular swiveling motion of the swiveling end 4227 includes both a component perpendicular to the target direction and a component parallel to the target direction.

[0091] In FIG. 14, a moving speed of the mobile platform is V0, and a moving direction thereof is a target direction. The sliding slot 4222 is approximately perpendicular to the target direction. At this time, the reciprocating movement of the cleaning substrate 4221 as a whole includes both a movement component parallel to the target direction of the automatic cleaning device and a movement component perpendicular to the target direction of the automatic cleaning device.

[0092] In some embodiments, the supporting platform 422 further includes an elastic detachable button 4229 disposed on at least one side of the supporting platform 422, for detachably connecting the supporting platform 422 to a pawl 4216 of the driving platform 421, so that the supporting platform 422 is detachably and mechanically fixed onto the driving platform 421, and fixed relative to the driving platform and the automatic cleaning device. At least one assembly region 4224 is disposed on the supporting platform 422, for assembling the cleaning head 410. The assembly region 4224 may be formed of an adhesive material with an adhesive layer.

[0093] According to embodiments of the present disclosure, as shown in FIG. 9, the cleaning head 410 includes a movable region 412 connected to the cleaning substrate 4221, to make an approximate reciprocating movement along the surface to be cleaned under the driving of the cleaning substrate 4221. The movable region 412 is disposed at a substantially central position of the cleaning head 410.

[0094] In some embodiments, an adhesive layer is provided on a side of the movable region 412 on which the movable region 412 is connected to the cleaning substrate 4221, and the movable region 412 is connected to the cleaning substrate 4221 through the adhesive layer.

[0095] In some embodiments, the cleaning head 410 further includes a fixed region 411 connected to a bottom of the supporting platform 422 through the at least one assembly region 4224. The fixed region 411 cleans at least a part of the operating surface along with the movement of the supporting platform 422.

[0096] In some embodiments, the cleaning head 410 further includes a flexible connection portion 413 disposed between the fixed region 411 and the movable region 412 for connecting the fixed region 411 and the movable region 412. The cleaning head 410 further includes a sliding fastener 414 extending along an edge of the cleaning head 410 and detachably mounted at an engagement position 4225 of the supporting platform 422.

[0097] In some embodiments, as shown in FIG. 9, the cleaning head 410 may be made of a material with certain elasticity, and is fixed to the surface of the supporting platform 422 through the adhesive layer, so as to achieve the reciprocating movement. The cleaning head 410 is always in contact with the surface to be cleaned during operation.

[0098] The water delivery mechanism includes a water discharging unit 4217 that may be directly or indirectly connected to a cleaning liquid outlet of a water tank (not shown), that is, a liquid outlet of the clean water tank. The cleaning liquid may flow to the water discharging unit 4217 via the cleaning liquid outlet of the water tank, and may be evenly coated on the surface to be cleaned through the water discharging unit. A connection member (not shown) may be provided on the water discharging unit, and the water discharging unit is connected to the cleaning liquid outlet of the water tank through the connection member. The water discharging unit is provided with a distribution port which may be a continuous opening or a combination of several discontinuous small openings, and several nozzles may be provided at the distribution port. The cleaning liquid flows to the distribution port via the cleaning liquid outlet of the water tank and the connection member of the water discharging unit, and is evenly coated on the operating surface via the distribution port.

[0099] The water delivery mechanism may further include a clean water pump 4219 and/or a clean water pump pipe 4218. The clean water pump 4219 may be communicated with the cleaning liquid outlet of the water tank directly, or communicated with the cleaning liquid outlet of the water tank through the clean water pump pipe 4218.

[0100] The clean water pump 4219 may be connected to the connection member of the water discharging unit, and configured to pump the cleaning liquid from the water tank to the water discharging unit. The clean water pump may be a gear pump, a vane pump, a plunger pump, a peristaltic pump, or the like.

[0101] The water delivery mechanism pumps the cleaning liquid out from the clean water tank through the clean water pump 4219 and the clean water pump pipe 4218, and transports the cleaning liquid to the water discharging unit. The water discharging unit 4217 may be a sprinkler head, a drip hole, a wet cloth, or the like, and may uniformly spread water on the cleaning head, so as to wet the cleaning head and the surface to be cleaned. Stains on the wetted surface to be cleaned can be cleaned more easily. In the wet cleaning module 400, the power/flow rate of the clean water pump may be adjusted.

[0102] In some embodiments, as shown in FIG. 17, the motor 4211 drives the clean water pump 4219 to wriggle through a gear set 42193. Through the wriggle of the clean water pump 4219, the clean water enters from a water inlet 42191, flows out of a water outlet 42192, and is then transported to the water discharging unit 4217 through the clean water pump pipe 4218. The water flowing out of the water discharging unit 4217 flows to the cleaning head 410 via the water discharging hole.

[0103] In some embodiments, as shown in FIG. 18, the motor 4211 drives a cable gear 42196 to rotate through the gear set 42193. A cable 42194 is wound on the cable gear 42196, and is wound and suspended on the driving platform 421. The cable gear 42196 pulls the cable 42194 to rise and drop, so as to lift and lower the driving platform 421. The cable gear 42196 and the cable 42194 are core components of the lifting module.

[0104] A clutch 42195 is disposed on the gear set 42193 and the cable gear 42196. By controlling the engagement and disengagement of the clutch 42195, the motor 4211 controls three motion modules. The motor 4211 rotates in one direction to drive the vibration member to vibrate and enable the clean water pump 4219 to supply water simultaneously. The motor 4211 rotates in an opposite direction to drive the lifting module to lift and lower through the cable 42194. In some embodiments, the combined design of the gear set realizes the control over the three motion modules in different combinations. For example, rotating the clean water pump in one direction supplies water, and rotating in the opposite direction realizes the control over lifting and lowering and vibration. In some embodiments, two motors may also be used to control the three motion modules, but an extra motor also increases the cost.

[0105] Since the cleaning module of the automatic cleaning device is provided with the dry cleaning module and the wet cleaning module, a more comprehensive cleaning function may be provided. Meanwhile, by adding the driving unit and the vibration region to the wet cleaning module, the cleaning head may be enabled to make a reciprocating movement, to repeatedly clean the surface to be cleaned. Therefore, in a movement trajectory of a cleaning robot, a region may be cleaned several times by the cleaning robot during one passage of the region, thereby greatly enhancing the cleaning effect, especially obvious for a region with more stains.

[0106] As shown in FIGs. 19-20, the wet cleaning module 400 is movably connected to the mobile platform 100 through a four-link lifting structure 500, and configured to clean at least a part of the operating surface by means of wet cleaning. The four-link lifting structure 500 is a parallelogram structure, for switching the wet cleaning module 400 between a lifting state and a lowering state. In the lifting state, the wet cleaning module 400 leaves the operating surface, as shown in FIG. 19, and in the lowering state, the wet cleaning module 400 is attached to the operating surface, as shown in FIG. 20.

[0107] As shown in FIGs. 21-22, the four-link lifting structure 500 includes a first connection end 501 for providing an active force to switch the wet cleaning module 400 between the lifting state and the lowering state, and a second connection end 502 disposed opposite to the first connection end 501 and rotating under the action of the active force. The first connection end 501 and the second connection end 502 are respectively located on both sides of the wet cleaning module 400, to lift or lower the wet cleaning module 400 by stably providing a lifting or lowering force.

[0108] In some embodiments, the first connection end 501 includes a first bracket 5011 fixedly connected to the bottom of the mobile platform 100. The first bracket 5011 has a shape roughly like a Chinese character "JL", and includes a cross beam 50111, a first longitudinal beam 50114 and a second longitudinal beam 50115. A tail end of each of the first longitudinal beam 50114 and the second longitudinal beam 50115 is fixedly connected to the mobile platform 100 through a bolt, to provide a supporting force when the wet cleaning module 400 is lifted and lowered.

[0109] The first connection end 501 further includes a first connection rod pair 5012, one end of the first connection rod pair 5012 is rotatably connected to the first bracket 5011, and the other end of which is rotatably connected to the wet cleaning module 400. The first connection rod pair 5012 may be of a hollowed structure, which can reduce an overall weight of a lifting end.

[0110] In some embodiments, the first connection rod pair 5012 includes a first connection rod 50121 and a second connection rod 50122 which are arranged in parallel. A first end of each of the first connection rod 50121 and the second connection rod 50122 is rotatably connected to the first longitudinal beam 50114 through a movable stud, and a second end of each of the first connection rod 50121 and the second connection rod 50122 is rotatably connected to the wet cleaning module 400 through a movable stud. For example, both ends of each of the first connection rod 50121 and the second connection rod 50122 are respectively provided with through holes having a diameter greater than a diameter of the movable stud, so that the movable stud may rotate freely within the through hole. The movable stud passes through the through hole and is fixedly connected to the first longitudinal beam 50114. When the motor 4211 provides a pulling force to the first ends through the cable, the first ends of the first connection rod 50121 and the second connection rod 50122 simultaneously rotate around the movable studs at the first ends, and the second ends thereof are lifted under the pulling force of the cable, so that the wet cleaning module 400 is lifted. When the motor 4211 releases the pulling force to the first ends through the cable, the first ends of the first connection rod 50121 and the second connection rod 50122 simultaneously rotate reversely around the movable studs at the first ends, and the second ends thereof are lowered under the action of gravity, so that the wet cleaning module 400 is lowered.

[0111] The lifting structure 500 further includes a cable 42194 for providing a pulling force to rotate the first connection rod pair 5012 within a preset angle. The cable 42194 includes a cable motor terminal 50131 connected to the driving unit 420. For example, the cable motor terminal 50131 is wounded on the gear connected to the output shaft of the motor, to extend and retract under the rotation of the motor. A cable bracket terminal 50132 is connected to the first bracket 5011. The motor lifts or lowers the second ends of the first connection rod 50121 and the second connection rod 50122 through the cable 42194.

[0112] In some embodiments, the first bracket 5011 further includes a sliding slot 50112 extending along a surface of the cross beam 50111, and a snapping hole 50113 penetrating the cross beam 50111 and disposed at an extension end of the sliding slot 50112, for accommodating and snapping the cable bracket terminal 50132. The cable 42194 is connected to the first ends of the first connection rod 50121 and the second connection rod 50122 through the sliding slot 50112 and the snapping hole 50113. The sliding slot 50112 can restrict a moving direction of the cable to ensure the stability of lifting of the module, and a width of the sliding slot should match with a diameter size of the cable.

[0113] As shown in FIG. 21, the second connection end 502 includes a second bracket 5021 fixedly connected to the bottom of the mobile platform 100, and a second connection rod pair 5022. One end of the second connection rod pair 5022 is rotatably connected to the second bracket 5021, and the other end of which is rotatably connected to the wet cleaning module 400. The second connection rod pair 5022 rotates along with the rotation of the first connection rod pair 5012. The second connection rod pair 5022 may be of a hollowed structure, which can reduce the overall weight of lifting and lowering ends.

[0114] In some embodiments, the second connection rod pair 5022 includes a third connection rod 50221 and a fourth connection rod 50222 which are arranged in parallel. A first end of each of the third connection rod 50221 and the fourth connection rod 50222 is rotatably connected to the second bracket 5021 through a movable stud, and a second end of each of the third connection rod 50221 and the fourth connection rod 50222 is rotatably connected to the wet cleaning module 400 through a movable stud. For example, both ends of each of the third connection rod 50221 and the fourth connection rod 50222 are respectively provided with through holes having a diameter greater than a diameter of the movable stud, so that the movable stud may rotate freely within the through hole. The movable stud passes through the through hole and is fixedly connected to the second bracket 5021 and the wet cleaning module 400 through. When the first connection end 501 rotates under the driving of the motor 4211, the first ends of the third connection rod 50221 and the fourth connection rod 50222 simultaneously rotate around the movable studs at the first ends, and the second ends of the third connection rod 50221 and the fourth connection rod 50222 simultaneously rotate around the movable studs at the second ends, so that the wet cleaning module 400 is lifted. When the first connection end 501 releases the pulling force, the third connection rod 50221 and the fourth connection rod 50222 simultaneously rotate reversely around the movable studs, so that the wet cleaning module 400 is lowered under the action of gravity.

[0115] By providing the four-link lifting structure between the wet cleaning module and the mobile platform, the wet cleaning module may be lifted and lowered relative to the mobile platform. When a mopping task is performed, the wet cleaning module is lowered to enable the wet cleaning module to be in contact with the ground, and when the mopping task is completed, the wet cleaning module is lifted to separate the wet cleaning module from the ground, thereby avoiding the increased resistance due to the existence of the cleaning module when the cleaning device moves freely on the surface to be cleaned.

[0116] In cooperation with a surface medium sensor and other sensors that can detect a surface type of the surface to be cleaned, the lifting module enables the wet cleaning module to perform a cleaning operation according to different surfaces to be cleaned. For example, the lifting module lifts the wet cleaning module in case of a carpet surface, and lowers the wet cleaning module in case of a floor surface, a floor tile surface, or the like, for cleaning. Thus, a more comprehensive cleaning effect is achieved.

[0117] As shown in FIG. 23, which is a diagram of the dry cleaning module 151 in a lifting state. A floating lifting structure 600 is connected to the dry cleaning module 151 and configured to enable the dry cleaning module 151 to passively move vertically relative to the mobile platform 100. In some embodiments, the floating lifting structure 600 is a parallelogram four-link lifting structure configured to passively switch the dry cleaning module 151 between a lifting state and a lowering state under the action of an external force.

[0118] In some embodiments, the floating lifting structure 600 includes a first fixed bracket 601 fixedly connected to the mobile platform 100, a second fixed bracket 602 fixedly connected to the dry cleaning module 151, and a connection rod pair 603. One end of the connection rod pair 603 is rotatably connected to the first fixed bracket 601 through a movable stud, and the other end of which is rotatably connected to the second fixed bracket 602 through a movable stud. The first fixed bracket 601 and the second fixed bracket 602 are connected through a flexible connection member. When encountering an obstacle, the dry cleaning module 151 is pushed upward, and the first fixed bracket 601 rotates around the connection rod pair 603 and then retracted upward relative to the second fixed bracket 602, so as to realize passive lifting. After passing the obstacle, the dry cleaning module 151 falls under the action of gravity and comes into contact with the operating surface, and the cleaning device continues to move forward for the cleaning task. With the parallelogram four-link lifting structure, the cleaning device can pass the obstacle more flexibly, and is not easy to be damaged.

[0119] In some embodiments, the connection rod pair 603 includes a first connection rod pair 6031. One end of the first connection rod pair 6031 is rotatably connected to a first end of the first fixed bracket 601 through a movable stud, and the other end of which is rotatably connected to a first end of the second fixed bracket 602 through a movable stud. A second connection rod pair 6032 is disposed opposite to the first connection rod pair 6031. One end of the second connection rod pair 6032 is rotatably connected to a second end of the first fixed bracket 601 through a movable stud, and the other end of which is rotatably connected to a second end of the second fixed bracket 602 through a movable stud. The first connection rod pair 6031 or the second connection rod pair 6032 may be of a hollowed structure, which can reduce the overall weight of lifting and lowering ends.

[0120] In some embodiments, the first connection rod pair 6031 includes a first connection rod 60311 and a second connection rod 60 > 12 which are arranged in parallel. One end of each of the first connection rod 60311 and the second connection rod 60312 is provided with a first shaft hole, and the other end thereof is provided with a second shaft hole. The movable studs pass through the first shaft holes, and rotatably fix the first connection rod 60311 and the second connection rod 60312 to the first end of the first fixed bracket 601. The movable studs pass through the second shaft holes, and rotatably fix the first connection rod 60311 and the second connection rod 60312 to the first end of the second fixed bracket 602. For example, both ends of each of the first connection rod 60311 and the second connection rod 60312 are respectively provided with snapping holes (not shown) having a diameter greater than that of the movable stud, so that the movable stud may rotate freely within the snapping hole, and is fixedly connected to the first fixed bracket 601 through the snapping hole. When encountering a raised obstacle, the dry cleaning module 151 is pushed upward under the action of the obstacle, the first ends of the first connection rod 60311 and the second connection rod 60312 simultaneously rotate around the movable studs at the first ends, and the second ends of the first connection rod 60311 and the second connection rod 60312 simultaneously rotate around the movable studs at the second ends, so that the dry cleaning module 151 is lifted. When passing the obstacle, the dry cleaning module 151 falls under the action of gravity and comes into contact with the operating surface.

[0121] In some embodiments, as shown in FIG. 24, which is a diagram of the dry cleaning module 151 in a lifting state, the second connection rod pair 6032 includes a third connection rod 60321 and a fourth connection rod 60322 which are arranged in parallel. One end of each of the third connection rod 60321 and the fourth connection rod 60322 is provided with a third shaft hole, and the other end thereof is provided with a fourth shaft hole. The movable studs pass through the third shaft holes and rotatably fix the third connection rod 60321 and the fourth connection rod 60322 to the second end of the first fixed bracket 601, and the movable studs pass through the fourth shaft holes and rotatably fix the third connection rod 60321 and the fourth connection rod 60322 to the second end of the second fixed bracket 602. For example, both ends of each of the third connection rod 60321 and the fourth connection rod 60322 are respectively provided with snapping holes (not shown) having a diameter greater than that of the movable stud, so that the movable stud may rotate freely within the snapping hole. The movable stud passes through the snapping hole and is fixedly connected to the first fixed bracket 601. When encountering a raised obstacle, the dry cleaning module 151 is pushed upward under the action of the obstacle, the first ends of the third connection rod 60321 and the fourth connection rod 60322 simultaneously rotate around the movable studs at the first ends, and the second ends of the third connection rod 60321 and the fourth connection rod 60322 simultaneously rotate around the movable studs at the second ends, so that the dry cleaning module 151 is lifted. When passing the obstacle, the dry cleaning module 151 falls under the action of gravity and comes into contact with the operating surface.

[0122] In some embodiments, the first fixed bracket 601 includes a first fixed part 6011 protruding from the first fixed bracket 601 and extending laterally outward, for carrying the first connection rod pair 6031, and a second fixed part 6012 disposed symmetrically with the first fixed part 6011, for carrying the second connection rod pair 6032. The first fixed part 6011 and the second fixed part 6012 are used to support the connection rod pairs in a protruding manner, so that the connection rod pairs may rotate freely, so as to ensure freely lifting and lowering of the dry cleaning module 151.

[0123] In some embodiments, the floating lifting structure 600 further includes a flexible connection member (not shown) connected between the first fixed bracket 601 and the second fixed bracket 602. When the operating surface is uneven, the second fixed bracket 602 moves vertically relative to the first fixed bracket 601 through the flexible connection member.

[0124] In the dry cleaning module, the four-link floating lifting structure is disposed to enable the dry cleaning module to passively move vertically relative to the mobile platform. When encountering an obstacle during the operation, the cleaning device can easily pass the obstacle through the four-link floating lifting structure, thereby avoiding the damage to the cleaning device from the obstacle.

Embodiment 2

[0125] According to embodiments of the present disclosure, as shown in FIG. 9, the present disclosure provides an automatic cleaning device. Structures in embodiments that are the same as those in the above embodiments have the same functions or effects, which will not be repeated herein. In some embodiments, the automatic cleaning device includes: a mobile platform 100 configured to move automatically on an operating surface; and a cleaning module 150 disposed on the mobile platform 100. The cleaning module 150 includes a dry cleaning module 151 configured to clean at least a part of the operating surface by means of dry cleaning, and a wet cleaning module 400 configured to clean at least a part of the operating surface by means of wet cleaning. The wet cleaning module 400 includes a cleaning head 410 for cleaning the operating surface, and a driving unit 420 for driving the cleaning head 410 to make a reciprocating movement along a target surface. The target surface is a part of the operation surface. As shown in FIGs. 25-27, the mobile platform 100 is provided with a thimble 1001, and the wet cleaning module 400 is provided with a slot 4001 matched with the thimble 1001 to limit a working position of the wet cleaning module 400. In some embodiments, the slot 4001 is cylindrical or square, which is not limited. The thimble can move directionally along the slot, so that the slot and the thimble play a role of a position limit during the lifting and lowering process of the lifting module, avoiding deviation of the lifting module. The spring can reduce the vibration of the pallet caused by the lowering state of the lifting module. In some embodiments, the wet cleaning module 400 further includes a driving platform 421 connected to a bottom surface of the mobile platform 100, and the slot 4001 is arranged on the driving platform 421.

[0126] In some embodiments, as shown in FIG. 25, the slot 4001 includes an elastic element 40011, and the elastic element 40011 extends from the slot 4001 toward the mobile platform 100. In some embodiments, the elastic element 40011 is a helical spring, an elastic sheet, or the like. For example, the elastic element may be fixed on the bottom or the top of the slot, which is not limited.

[0127] In some embodiments, as shown in FIGs. 26-27, the slot 4001 further includes a thimble sheath 40012, and the thimble sheath 40012 extends upward from the bottom of the slot 4001, so that the thimble 1001 make a telescopic movement within the thimble sheath 40012. The thimble sheath 40012 is a hollowed structure, such as a cylindrical or square sheath structure. When the elastic element 40011 is a helical spring, the helical spring is arranged around the periphery of the thimble sheath 40012.

[0128] In some embodiments, the thimble 1001 includes a sliding portion 10011 and a fixed portion 10012. The sliding portion 10011 slides along the thimble sheath 40012, and the fixed portion 10012 is fixed to the mobile platform 100. In some embodiments, the fixed portion 10012 includes a thread structure, and is fixed to the mobile platform 100 through the thread structure. In some embodiments, the thimble 1001 may also be fixed to the mobile platform 100 by welding.

[0129] In some embodiments, an inner diameter of the thimble sheath 40012 is slightly larger than an outer diameter of the sliding portion 10011. In this way, when the sliding portion 10011 slides freely within the thimble sheath 40012, the limiting effect will not be reduced due to being too loose.

[0130] In some embodiments, a height of the elastic element 40011 in a natural state is greater than a height of the thimble sheath 40012. In this way, it is ensured that the elastic element has sufficient elastic support force. When the lifting module is lifted and lowered, the elastic element can still achieve elastic support when compressed, so that the thimble will not interfere with the bottom of the thimble sheath.

[0131] The present disclosure provides an automatic cleaning device. A slot is provided on the wet cleaning module, a spring is provided inside the slot, and a thimble corresponding to the slot is provided on the mobile platform, so that the thimble can move directionally along the slot, and during the lifting and lowering of the lifting module, the slot and the thimble play the role of a position limit, so as to avoid deviation of the lifting module. Further, the spring can reduce the vibration of the pallet caused by the lowering state of the lifting module.

[0132] In some embodiments, as shown in FIG. 10, the wet cleaning module 400 includes a cleaning head 410 for cleaning the operating surface, a driving unit 420 for driving the cleaning head 410 to make a reciprocating movement along a target surface, the target surface being a part of the operating surface, and a driving platform 421 connected to a bottom surface of the mobile platform 100 for providing a driving force. The driving platform 421 includes a motor 4211 arranged on a side of the driving platform 421 close to the mobile platform 100, for outputting power through an output shaft 42111 of the motor, and a connection rod 4214 arranged on a side of the driving platform 421 opposite to the motor 4211. One end of the connection rod 4214 is connected with the motor output shaft 42111. A buffer clip 42112 is provided at a joint between the connection rod 4214 and the output shaft 42111 of the motor.

[0133] In some embodiments, as shown in an enlarged view of FIG. 28, an end of the output shaft 42111 of the motor includes an annular groove 42113, and the buffer clip 42112 is snapped into the annular groove 42113.

[0134] In some embodiments, as shown in FIG. 29, the buffer clip 42112 is a sheet structure. In some embodiments, the buffer clip 42112 has a certain degree of elasticity. The buffer clip 42112 includes a notch 42114 for providing an entrance when the buffer clip 42112 is snapped into the annular groove 42113. The buffer clip 42112 is snapped into the annular groove 42113 through the notch 42114. The buffer clip 42112 includes a snapping surface 42115 for clasping the annular groove 42113 tightly when the buffer clip 42112 is snapped into the annular groove 42113.

[0135] In some embodiments, the snapping surface 42115 is a continuous structure or an intermittent structure. When the snapping surface 42115 is a continuous structure, it can be a continuous snapping surface of 90-270 degrees. A specific continuous length of the snapping surface is not limited, and the best effect is to actually clasp the annular groove 42113. When the snapping surface 42115 is an intermittent structure, it is appropriate to have 3 or 4 intermittent snapping surfaces. A specific continuous length of each snapping surface is not limited. The continuous length of each snapping surface may be the same or different. The best effect is to actually clasp the annular groove 42113.

[0136] In some embodiments, one end of the connection rod 4214 is provided with an opening 42116, and the output shaft 42111 of the motor protrudes from the opening 42116 and is snapped by the buffer clip 42112.

[0137] In some embodiments, the driving platform 421 further includes a vibration member 4213 connected to the connection rod 4214, to make an approximate reciprocating movement under the driving of the motor 4211. An extending direction of the vibration member 4213 is substantially perpendicular to an extending direction of the connection rod 4214. The driving platform 421 further includes a vibration buffer unit 4215 arranged on the connection rod 4214.

[0138] The present disclosure provides an automatic cleaning device. A buffer clip is provided at a joint between the connection rod of the wet cleaning module and the motor output shaft. When the mopping module encounters ground fluctuations or obstacles during the mopping process, the vibration damage to the motor caused by the displacement in the vertical direction can be reduced, thereby reducing the damage to the reliability of the overall structure and improving the service life of the mopping module.

[0139] It should be noted that various embodiments in the description are described in a progressive manner, each embodiment focuses on the differences from other embodiments, and the same or similar parts among the various embodiments may refer to one another. Since the system or device disclosed in the embodiment corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts may refer to the description of the method part.

[0140] The above embodiments are only used to illustrate the technical solutions of the present disclosure and are not intended to limit the present disclosure. Although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill s in the art should understand that, they can still make modifications to the technical solutions described in the foregoing embodiments or make equivalent substitutions to some of the technical features; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present disclosure.

Claims

1. An automatic cleaning device, comprising:

a mobile platform (100) configured to move automatically on an operating surface; and

a cleaning module (150) arranged on the mobile platform (100), and comprising:

a dry cleaning module (151) configured to clean at least a part of the operating surface by means of dry cleaning; and

a wet cleaning module (400) configured to clean at least a part of the operating surface by means of wet cleaning, wherein the wet cleaning module (400) comprises:

a cleaning head (410) for cleaning the operating surface, and,

a driving unit (420) for driving the cleaning head (410) to make a reciprocating movement along a target surface, wherein the target surface is a part of the operating surface,

wherein the mobile platform (100) is provided with a thimble (1001), and the wet cleaning module (400) is provided with a slot (4001) matched with the thimble (1001), for limiting a working position of the wet cleaning module (400).

2. The automatic cleaning device according to claim 1, wherein the slot (4001) comprises an elastic element (40011), and the elastic element (40011) extends from the slot (4001) toward the mobile platform (100).

3. The automatic cleaning device according to claim 2, wherein the slot (4001) further comprises a thimble sheath (40012), and the thimble sheath (40012) extends upward from a bottom of the slot (4001), allowing the thimble (1001) to make a telescopic movement within the thimble sheath (40012).

4. The automatic cleaning device according to claim 3, wherein the elastic element (40011) is a helical spring, and the helical spring is arranged around the periphery of the thimble sheath (40012).

5. The automatic cleaning device according to claim 3, wherein the thimble (1001) comprises a sliding portion (10011) and a fixed portion (10012), the sliding portion (10011) slides along the thimble sheath (40012), and the fixed portion (10012) is fixed to the mobile platform (100).

6. The automatic cleaning device according to claim 5, wherein the fixed portion (10012) comprises a thread structure, and is fixed to the mobile platform (100) through the thread structure.

7. The automatic cleaning device according to claim 5, wherein an inner diameter of the thimble sheath (40012) is slightly larger than an outer diameter of the sliding portion (10011).

8. The automatic cleaning device according to claim 3, wherein a height of the elastic element (4001 1) in a natural state is greater than a height of the thimble sheath (40012).

9. The automatic cleaning device according to any one of claims 1 to 8, wherein the wet cleaning module (400) further comprises a driving platform (421) connected to a bottom surface of the mobile platform (100), and the slot (4001) is arranged on the driving platform (421).

10. The automatic cleaning device according to claim 9, wherein the slot (4001) is cylindrical or square.

Drawing