CRANE

Abstract

 The present invention relates to a crane (1) comprising a base body (2) configured to rest upon a bearing surface (S), a boom (3) designed to move between a working state and a parking state, extending away from the body (2) between a lower portion (31) and an opposite upper portion (32), the boom (3) is hinged to the body (2) in a hinging zone (4) at the lower portion (31) and is able to move relative to the body (2) in a horizontal and/or vertical direction in the working state, a cable (5) connected to the body (2) and to the boom (3) at the upper portion (32). The crane is characterized in that it comprises a counter-frame (6) associated with the boom (3), which extends between a lower end (61) and an opposite upper end (62), the upper end (62) of the counter-frame (6) is hinged to the boom (3), the counter-frame (6) is configured to move between a first configuration in which the lower end (61) is connected to the lower portion (31) of the boom (3) when the boom (3) is in the working state and a second configuration in which the lower end (61) of the counter-frame (6) is released from the boom (3) and is connected to the body (2) when the boom (3) is in the parking state.

Description

Field of the invention

[0001] The present invention relates to a crane, namely a cable crane, as defined in the preamble of claim 1.

[0002] The present invention is used advantageously, but without limitation, to lift and move loads, such as materials and/or goods, e.g. for the construction of buildings.

Background art

[0003] Cable cranes are known in the art for lifting and moving loads. These cranes comprise a base body, which rests on a bearing surface, and has a movable boom connected thereto to form an angle with the body in the vertical and horizontal directions. Specifically, this boom extends between a lower portion, hinged to the body, and an upper portion, indirectly connected to the body by a cable.

[0004] Such cable cranes also comprise two or more drums, one of which has the load-bearing cable wound thereupon. The possibility of having the load-bearing cable mounted to a motor-driven drum affords quicker tensioning and haul back after work, which will reduce assembly and disassembly times.

[0005] Cranes are also known which use a hydraulic piston instead of the cable.

[0006] When the crane is not in operation, whether it is a cable crane or a hydraulic piston crane, it should be advantageously moved to a parking state, i.e., by tilting the boom relative to the bearing surface to a greater extent than in the state in which the crane is working. This will reduce the overall size of the crane.

[0007] EP 1619159 A2, US 5484069 A, JP S6093691 U and US 2012/152878 A1 disclose a few examples of various types of cranes.

Problem of the prior art

[0008] One drawback of cable cranes is that, in strong winds, a boom with a steep upward tilt may tip over. In these cases, since the cable does not bear the collapse, the boom falls back and crushes against the body. Therefore, in order to meet safety conditions, these cranes may be parked with a predetermined parking angle of not more than 65°.

[0009] However, in cranes with a piston, the boom may be tilted to a greater extent in the parking states, to angles close to 80°, thereby providing a considerably smaller overall size, because the piston provides structural support.

[0010] One drawback of the cranes comprising the hydraulic piston is that the operation of such piston requires the provision of oil tanks, which are often prone to leakage and may cause damage to the equipment. Such tanks also require the presence of tilters which undesirably require maintenance.

SUMMARY OF THE INVENTION

[0011] Therefore, the technical purpose of the present invention is to provide a cable crane that can obviate the aforementioned prior art drawbacks.

[0012] In particular, one object of the present invention is to provide a cable crane that can afford parking angles greater than 65°, to reduce the overall dimensions in non-working states, with no risk of system collapse, while avoiding the disadvantages caused by the presence of the hydraulic piston.

[0013] The aforementioned technical purpose and objects are substantially fulfilled by a crane that comprises the technical features as disclosed in one or more of the accompanying claims.

Benefits of the invention

[0014] In particular, the cable crane of the present invention solves the technical problem in that it comprises a counter-frame that can add structural stability to the system.

[0015] With this crane parking angles of more than 65° are feasible, which will provide a more compact crane in the parking state.

[0016] Also, this crane can use the cable technology, without requiring a hydraulic piston, while achieving the same parking angles as the cranes with pistons.

Brief description of the figures

[0017] The characteristics and advantages of the present invention will result from the following detailed description of a possible practical embodiment, illustrated as a non-limiting example in the annexed drawings, in which:

• Figure 1 shows a lateral view of a crane of the prior art;
• Figure 2 shows a lateral view of a portion of a crane of the present invention in two working states;
• Figure 3 shows a detail of the crane of Figure 1, with certain parts omitted for simplicity;
• Figure 4 shows a detail of the crane of Figure 1, with certain parts omitted for simplicity.

DETAILED DESCRIPTION OF THE INVENTION

[0018] Referring to the accompanying drawings, the present invention relates to a crane designated by numeral 1.

[0019] The crane 1 comprises a base body 2 configured to rest on a bearing surface S. The base body 2 preferably comprises a cabin (not shown) configured to accommodate an operator.

[0020] The crane 1 also comprises a boom 3 configured to move loads. This boom 3 extends away from the body 2 between a lower portion 31 and an opposite upper portion 32.

[0021] It should be noted that the boom 3 is hinged to the body 2 in a hinging zone 4 at the lower portion 31.

[0022] The boom 3 is able move between a working state and a parking state.

[0023] It should be noted that, as used herein, "working state" means that the boom 3 is arranged for the crane to be able to perform its load lifting and/or moving task, i.e. is configured to move in the vertical and/or horizontal directions. On the other hand, "parking state" refers to a state in which the crane is not working, i.e. the boom 3 is arranged to be unable to perform its load lifting and/or moving task, and is arranged to remain still.

[0024] Accordingly, the boom 3 is able to move relative to the body 2 in the horizontal and/or vertical directions when it is in the working state.

[0025] More in detail, "able to move in the horizontal direction" means that the boom 3 is configured to move relative to a plane parallel to the bearing surface S, thereby defining a fixed angle whose vertex is in the hinging zone 4. In other words, the boom 3 keeps a fixed tilt relative to the bearing surface S as it moves, whereas the direction of the projection P of the boom 3 on such bearing surface changes.

[0026] On the other hand, "able to move in the vertical direction" means that the boom 3 is configured to change its angle relative to a plane parallel to the bearing surface S as it moves, whereas the projection P of the boom 3 on the bearing surface S keeps the same direction. In other words, the boom 3 only changes its tilt relative to the bearing surface S as it moves.

[0027] The boom 3 also combines the above two movements as it moves, i.e. both changing its tilt relative to the bearing surface S and changing its direction on the bearing surface S.

[0028] The parking state is reached by a vertical movement of the boom 3.

[0029] According to the present invention, when the crane 1 is not required to be used, the boom 3 is moved to the parking state, i.e. tilted to a position in which the length of the projection P of the boom 3 on the bearing surface S is as small as possible, to reduce the bulk. In other words, the upper portion of the boom 3 is moved upwards and as far as possible from the bearing surface S. Therefore, here, in the parking state the boom 3 forms a predetermined parking angle with a plane parallel to the bearing surface S. The parking state is always a non-working state, irrespective of the angle attained by the boom 3, i.e. irrespective of the predetermined parking angle.

[0030] More in detail, in the working state the boom 3 defines a first angular range α relative to the bearing surface S on which the body 2 lies, which ranges between a first angular value and a second angular value. On the other hand, in the parking state, the crane defines a second angular range β comprising the first angular range α.

[0031] The first angular range α is formed by the first upright 33 and a plane parallel to the bearing surface S, and has its vertex in the hinging zone 4. The second angular range β, also formed by the first upright 33 and a plane parallel to the bearing surface S and having its vertex in the hinging zone 4, has the boom 3 more tilted upwards away from the bearing surface S.

[0032] In particular, the second angular range β is greater than the first angular range α. This is because the boom 3 is more tilted than in working states. The second angular range β defines the predetermined parking angle.

[0033] According to alternative embodiments of the present invention, not included herein, the first angular range α may be equal to or greater than the second angular range β.

[0034] In other words, the boom 3 is more tilted relative to the bearing surface S than in the working state.

[0035] Preferably, the boom 3 can be driven from a control panel, located inside the cab, and comprising driving elements.

[0036] Preferably, the crane 1 comprises a cable 5, which is connected to the body 2 and to the boom 3 at the upper portion 32 by means of suitable drums, not shown in the figures but known to the skilled person. In other words, the crane 1 of the present invention is preferably a "cable crane".

[0037] The crane 1 further comprises a transverse element known as A frame 12. Such A frame 12 is connected to the body 2, and extends away from the body 2 and from the boom 3 starting from the hinging zone 4.

[0038] In particular, the cable 5 passes through the A frame 12 at the end of the A frame 12 that is not connected to the hinging zone 4.

[0039] The cable 5 is configured to be always taut. Therefore, at each movement of the boom 3, the cable winds or unwinds on/from a respective drum located in the body 2 and passes through the end of the A frame 12 not connected to the hinging zone 4.

[0040] According to a peculiar aspect of the present description, the crane 1 comprises a counter-frame 6 associated with the boom 3. This counter-frame 6 is configured to provide structural support to the boom 3 when the crane 1 is in a parking state.

[0041] For this purpose, the counter-frame 6 extends between a lower end 61 and an opposite upper end 62.

[0042] In particular, the upper end 62 of the counter-frame 6 is hinged to the boom 3.

[0043] Thus, the counter-frame is configured to move between a first configuration in which the lower end 61 is connected to the lower portion 31 of the boom 3 when the boom 3 is in the working state and a second configuration in which the lower end 61 of the counter-frame 6 is released from the boom 3 and is connected to the body 2 when the boom 3 is in the parking state.

[0044] Advantageously, when the boom 3 is in the parking state, the counter-frame 6 provides mechanical support and the boom 3 does not collapse on the cable 5.

[0045] Advantageously, predetermined parking angles of more than 65° may be safely supported, because the counter-frame 6 provides structural support to the boom 3. In particular, in the parking state, the counter-frame 6 acts as a strut, preventing movement of the boom 3 in the vertical direction and therefore keeping it still at a predetermined angle, i.e. the predetermined parking angle.

[0046] More in detail, the boom 3 comprises at least a first upright 33 and a second upright 34. The first upright 33 extends between the hinging zone 4 and a first end 331. The second upright 34 is parallel to the first upright 33 and extends to a smaller length than the first upright 33.

[0047] The boom 3 further comprises a first portion 35 transverse to the first upright 33 and to the second upright 34. The first transverse portion 35 is configured to connect the first upright 33 with the second upright 34. The first transverse portion 35 extends between the hinging zone 4 and a first end 341 of the second upright 34.

[0048] The boom 3 comprises a second portion 36 transverse to the first upright 33 and to the second upright 34. The second transverse portion 36 is configured to connect the first upright 33 with the second upright 34. The second transverse portion 34 extends between the first end 331 of the first upright 33 and a second end 342 of the second upright 34 opposite to the first end 341.

[0049] The counter-frame 6 is connected to the boom 3 at the first end 341 of the second upright 34.

[0050] According to one aspect, in the first configuration, the counter-frame 6 is parallel to and adjacent to the first transverse portion 35, whereas in the second configuration, the counter-frame 6 is parallel to the first upright 33 and forms an extension of the second upright 34.

[0051] Preferably, the crane 1 of the present invention is designed to be assembled in a modular manner. More in detail, the boom 3 has modules of predetermined size such as the first 35 and the second 36 transverse portions, and modules having a size that can vary from crane to crane, such as the first upright 33 and the second upright 34.

[0052] Advantageously, the counter-frame 6 is an element that can be adapted to various cranes 1 regardless of the length of the boom 3, as it is placed at the junction between the second upright 34 and the first transverse portion 35 which has a predetermined fixed length.

[0053] The lower end 61 of the counter-frame 6 comprises a head 7 configured to couple with the boom 3 when the boom 3 is in the working state. The head 7 is also configured to couple with the body 2 when the boom 3 is in the parking state.

[0054] In this regard, the boom 3 comprises respective first engagement means 8 and the body 2 comprises respective second engagement means 9. The first engagement means 8 and the second engagement means 9 are configured to couple with the head 7.

[0055] Preferably, the head 7 is configured to provide a male-female coupling with the first engagement means 8 and the second engagement means 9.

[0056] More in detail, the first engagement means 8 are located at the second upright 34. The first engagement means 8 comprise locking pins configured to keep the counter-frame 6 rigidly joined with the boom 3 in the working state, i.e. when the boom 3 is tilted with respect to the bearing surface S by a smaller angle than in the parking state, and is closer thereto.

[0057] In the first configuration, the counter-frame 6 extends between the first end 341 of the second upright 34 and the hinging zone 4.

[0058] In particular, the second engagement means 9 comprise a seat 10 which is configured to receive the head 7 of the counter-frame 6.

[0059] In the second configuration, the counter-frame 6 extends between the first end 341 of the second upright 34 and the seat 10. The seat 10 is formed with a radial clearance with the head 7 for easier insertion of the head into the seat 10.

[0060] For this purpose lock means 11 are provided for securing the head 7 of the counter-frame 6 to the seat 10 when the head 7 is coupled to the second engagement means 9. That is, once the head 7 is inserted in the seat 10, the lock means can hold the head 7 still inside the seat 10.

[0061] Preferably, such lock means 11 comprise a safety tooth 14 comprising a return element. This return element is, for example, a spring.

[0062] Particularly referring to Figures 3 and 4, the head 7 comprises, for example, a male insert portion 15 adapted to be inserted into the seat 10.

[0063] Therefore, the seat 10 comprises respective female coupling portions 16 in which said male insert portion can be fitted. The tooth 14 is snapped in place to close the seat 10 over the head 7.

[0064] It should be noted that the boom 3 further preferably comprises a handle 13 located at the head 7 to allow an operator to easily maneuver the boom 3 to move it to the second configuration.

[0065] The present invention further relates to a method of parking a crane 1 of the present invention.

[0066] The method comprises a first step of moving the boom 3 from the working state to an operating state to cause the boom 3 to define a predetermined operating angle with respect to the bearing surface S.

[0067] This step is preferably carried out mechanically by an operator inside the control cab.

[0068] The step of moving the boom 3 to a predetermined operating angle requires the boom 3 to be tilted by an angle that is smaller than a predetermined parking angle, with respect to the bearing surface S.

[0069] Therefore, the method requires the counter-frame 6 to be disconnected from the boom 3.

[0070] By this arrangement, once the boom 3 has been moved to the predetermined operating angle, and once the counter-frame 6 has been disconnected from the boom 3, the counter-frame 6 may be placed in the seat 10. Preferably, the counter-frame 6 oscillates by gravity until reaching a position close to the seat 10. Alternatively, the counter-frame 6 may also be driven mechanically by motor means proximate to the seat 10. For example, these motor means may comprise a piston that accompanies the counter-frame 6 to the desired position.

[0071] A subsequent step of connecting the lower end 61 of the counter-frame 6 to the body 2 follows, so as to move the counter-frame 6 from the first configuration to the second configuration.

[0072] The step of connecting the lower end 61 of the counter-frame 6 comprises the step of coupling the lower end 61 of the counter-frame 6 with a seat 10 in the body 2. In other words, in this step the head 7 is inserted into the seat 10. The step of positioning the head 7 inside the seat 10 is preferably carried out manually by an operator using the handle 13.

[0073] Once the counter-frame 6 has been positioned in the second configuration, the boom 3 defines a predetermined parking angle and may advantageously have a reduced bulk as compared with the working state.

[0074] Preferably, the predetermined parking angle is greater than 80°. More preferably, this angle is 82°. In other words, in the second configuration the boom 3 defines an angle of 82° with respect to a plane parallel to the bearing surface S. By way of example, the operating angle is about 79° if the predetermined parking angle is 82°.

[0075] A skilled person may obviously envisage a number of equivalent changes to the above discussed variants, without departure from the scope defined by the appended claims.

Claims

1. A crane (1) comprising

- a base body (2) configured to rest on a bearing surface (S),

- a boom (3) designed to move between a working state and a parking state, said boom (3) extending away from the body (2) between a lower portion (31) and an opposite upper portion (32), said boom (3) being hinged to the body (2) in a hinging zone (4) at the lower portion (31) and being able to move relative to the body (2) in a horizontal and/or vertical direction between a working state and a parking state,

- a cable (5) connected to the body (2) and the boom (3) at the upper portion (32);
characterized in that it comprises

- a counter-frame (6) associated with the boom (3) and extending between a lower end (61) and an opposite upper end (62), the upper end (62) of said counter-frame (6) being hinged to the boom (3), said counter-frame (6) being configured to move between a first configuration in which the lower end (61) is connected to the lower portion (31) of the boom (3) when said boom (3) is in said working state and a second configuration in which the lower end (61) of the counter-frame (6) is released from the boom (3) and is connected to the body (2) when said boom (3) is in said parking state.

2. A crane (1) as claimed in claim 1, wherein said lower end (61) of said counter-frame (6) comprises a head (7) configured to couple with the boom (3) when the boom (3) is in the working state and with the body (2) when the boom (3) is in the parking state, said boom (3) comprising respective first engagement means (8) and said body (2) comprising respective second engagement means (9), said first engagement means (8) and second engagement means (9) being configured to couple with the head (7).

3. A crane (1) as claimed in claim 2, wherein the second engagement means (9) comprise a seat (10) which is configured to receive the head (7) of the counter-frame (6).

4. A crane (1) as claimed in claim 3, wherein the seat (10) comprises lock means (11) for securing the head (7) of the counter-frame (6) to the seat (10) when the head (7) is coupled to the second engagement means (9).

5. A crane (1) as claimed in any of the preceding claims, wherein the boom (3) comprises:

- at least a first upright (33) and a second upright (34), said first upright (33) extending between the hinging zone (4) and a first end (331), said second upright (34) being parallel to the first upright (33) and extending to a smaller length than said first upright (33),

- a first transverse portion (35), transverse to said first upright (33) and second upright (34) configured to connect said first upright (33) with said second upright (34), said first transverse portion (35) extending between the hinging zone (4) and a first end (341) of said second upright (34),

- a second transverse portion (36), transverse to said first upright (33) and second upright (34) configured to connect said first upright (33) with said second upright (34), said second transverse portion (34) extending between said first end (331) of said first upright (33) and a second end (342) opposite to the first end (341) of said second upright (34),

said counter-frame (6) being connected to the boom (3) at the first end (341) of the second upright (34).

6. A crane (1) as claimed in claim 5, wherein the counter-frame (6), when in the second configuration, is parallel to the first upright (33) and forms an extension of the second upright (34).

7. A crane (1) as claimed in claim 5 or 6, wherein the counter-frame (6), when in the first configuration, is parallel to and adjacent to the first transverse portion (35).

8. A crane (1) as claimed in any of the preceding claims, wherein said boom (3), in said working state, defines a first angular range (α) relative to the bearing surface (S) on which the body (2) lies, which ranges between a first angular value and a second angular value, and said boom (3), in said parking state, defines a second angular range (β) comprising the first angular range (α).

9. A method of parking a crane (1) as claimed in any of the preceding claims, said method comprising the steps of:

- moving the boom (3) from said working state to a operating state with said boom (3) defining a predetermined operating angle with respect to the bearing surface (S);

- disconnecting the counter-frame (6) from the boom (3),

- connecting the lower end (61) of said counter-frame (6) to the body (2) for said counter-frame (6) to move from said first configuration to said second configuration.

10. A method as claimed in claim 9, wherein said step of connecting the lower end (61) of said counter-frame (6) comprises the step of coupling said lower end (61) of the counter-frame (6) with a seat (10) in said body (2).

Drawing