VACUUM CLEANER HEAD

Abstract

 A vacuum cleaner head comprises a body 10 having a bottom soleplate 16 which defines a transversely extending suction mouth 15. An elongate floor-engaging brush 17 and wiper 19 extend axially of the suction mouth 15 on respective front and rear sides thereof. The brush 17 and wiper 19 are displaceable by pedal 20 from a retracted position inside the body 10 to an extended position below the bottom surface of the body. A dial 24 is provided for lowering a wheel 12 at the rear of the body 10 to lift the rear of the body 10 relative to the floor surface being cleaned and vice-versa. The head can easily be configured for efficient cleaning of hard floors and carpets and for intensive carpet cleaning.

Description

[0001] This invention relates to a vacuum cleaner head which is particularly suited to cleaning carpets and hard floors.

[0002] In so-called canister vacuum cleaners, a vacuum cleaner head is pivoted at the end of a tubular wand which is connected to the body of the cleaner by an elongate flexible duct. The body of the cleaner comprises a motor and fan unit that is arranged to draw air through the head into the body where any entrained dirt and dust in the air is separated and collected. Sometimes the head may be detachable, so that the user can fit other kinds of cleaning tools to the wand.

[0003] Heads for use with canister cleaners are commonly of a type suitable for cleaning both carpets and hard floors (e.g. wooden or tiles). FR2695023 discloses a typical head for a canister cleaner, the head comprising a fixed sole plate provided with a transversely extending elongate suction mouth, and a movable carrier whereby brush strips and/or rubber wiper blades can be retracted inside the head for carpet cleaning or extended to project beneath the sole plate for hard floor cleaning. In their extended state, the brush strips or wiper blades are generally located to the front and the rear of the sole plate. Selection of the brush setting is generally under operator control by means of a mechanism activated by a pedal on the upper surface of the nozzle body.

[0004] European Union Directives require that most kinds of vacuum cleaners are provided with an Energy Label, which provides consumers with information on the annual energy consumption (AE) and the dust pick up performance or so-called DPU on hard floors and/or carpets depending on the intended use of the cleaner. The annual energy consumption (AE) and DPU of the cleaner have to be indicated on the Energy Label as grades in the range of A (best) to G (poorest).

[0005] The standard test procedure whereby the energy efficiency grade of general purpose vacuum cleaners is determined involves evaluation of the DPU performance on both of the above types of floor surfaces. The value on which the AE energy consumption rating is based is a product of the sum of 50% of the observed DPU values for the respective floor types and the motor power needed to achieve the DPU for each floor type.

[0006] A problem with general purpose vacuum cleaners is that the head may not achieve a good DPU at one or both floor types, with the result that the DPU rating and the overall annual energy consumption (AE) rating of the cleaner may be poor. This will be a particular problem from September 2017 when further European Union Directives limit the power of vacuum cleaners to 900 watts.

[0007] When cleaning carpets, a problem of heads of the type disclosed in FR2695023 is that the sole plate can adhere to the carpet under the applied suction when the brush strips and/or rubber wiper blades are raised. When hard floor, a problem of heads of the type disclosed in FR2695023 is that the sole plate can also adhere to the hard floor under the applied suction when the brush strips and/or rubber wiper blades are lowered. Both situations give rise to the need for high push forces (tractive effort) in use. Furthermore, since airflow into the head is impeded when the head fully or partially adheres to the floor, the achieved DPU is adversely affected.

[0008] GB2528145 discloses a vacuum cleaner head comprising a front, a rear, a body having a bottom surface which defines a transversely extending suction mouth, front and rear depending elongate floor-engaging members which extend axially of the suction mouth on respective opposite sides thereof and which are displaceable from a retracted position inside the body to an extended position below the bottom surface of the body, and actuator means arranged for selectively extending or retracting the floor-engaging members and for selectively raising or lowering the front of the body relative to the floor surface being cleaned.

[0009] US4638526 discloses a vacuum cleaner head comprising a front, a rear, a body having a bottom surface which defines a transversely extending suction mouth, front and rear depending elongate floor-engaging members which extend axially of the suction mouth on respective opposite sides thereof and which are displaceable from a retracted position inside the body to an extended position below the bottom surface of the body, and actuator means arranged for selectively extending or retracting the floor-engaging members.

[0010] The object of the present invention is to provide a general purpose vacuum cleaner head for use on both carpets and hard floors and which has an improved DPU performance compared with known general purpose vacuum cleaner heads.

[0011] In accordance with the present invention, there is provided a vacuum cleaner head of the type disclosed in US4638526 which is characterised in that the actuator means is arranged for selectively raising or lowering the rear of the body relative to the floor surface being cleaned.

[0012] In use, for hard floor cleaning, the rear of the body is raised and the floor-engaging members are extended to a position below the bottom surface of the body. The forwardly and downwardly inclined attitude of the body makes head easier to push over the hard floor surface being cleaned and, since the suction mouth is raised above the floor surface, any tendency for the head to adhere the floor is alleviated. The floor-engaging members contact the floor surface and promote the flow of air over the underlying floor surface so that a good DPU performance is achieved for hard floors.

[0013] In use, for normal carpet cleaning, the rear of the body is raised and the floor-engaging members are retracted to a position above the bottom surface of the body. The forwardly and downwardly inclined attitude of the body again makes head easier to push over the carpet being cleaned and, since the suction mouth is raised above the floor surface, any tendency for the head to adhere the carpet is alleviated. Only the front of the bottom surface of the body engages the carpet and suction mouth is slightly raised above the surface of the carpet. The front of the bottom surface of the body acts to bend the carpet pile forwardly so that dirt and dust can be drawn out of the carpet by the suction behind the front surface. In this manner a good DPU performance is achieved for carpets.

[0014] In use, for intensive carpet cleaning, the rear of the body is lowered and the floor-engaging members are retracted to a position above the bottom surface of the body. The entire bottom surface of the body and the suction mouth are thus in direct contact with the carpet and both the front and rear of the bottom act to successively bend the carpet pile away from the suction mouth on successive forwards and rearwards movements of the head, so that dirt and dust can be drawn out of the carpet by the suction. Since this mode of use will result in some increased tractive effort, it is only intended for occasional intensive carpet cleaning with a better DPU performance than that which is achieved for normal carpet cleaning.

[0015] Preferably the bottom surface of the body has substantially flat front and rear surface portions which respectively extend from front and rear edges of the suction mouth respectively.

[0016] A rib may extend across the rear portion behind the suction mouth.

[0017] On the forward stroke of the head, the rib augments dust removal as it penetrates, agitates and flicks engrained dust in the carpet pile towards the surface of the carpet and away from the influence of the suction. On the rearward stroke, the displaced dust on the surface of the carpet is drawn into the suction mouth under the action of airflow and reduced agitation. The repeated backwards and forwards movement of the head brings more deeply embedded dust to the surface of the carpet on successive strokes.

[0018] A lint picker comprising tufts of fine fibres may extend across the rear portion behind the suction mouth. The tufts of the lint picker are aligned in the same direction, such that the lint picker will collect matter such as hair, fibres and lint on the forward stroke of the head, and release such collected matter into the applied suction on the rearward stroke.

[0019] The front of the bottom surface of the body may be inclined upwardly and away from the front edges of the suction mouth to provide a surface on which the head can ride in the normal carpet cleaning mode. The upwardly inclined front of the bottom surface of the body also makes it easier to move the head forwards over the carpet in the intensive carpet cleaning mode

[0020] The rear edge of the suction mouth may be curved forwardly at its outer ends. The longitudinal profile of the rib or lint picker may substantially follow the longitudinal profile of the rear edge of the suction mouth. The complementary shape of the rib or lint picker with the rear edge of the suction mouth improves the removal of matter from the carpet.

[0021] It will be appreciated that the lint picker and/or the rib will be raised above the floor surface in the hard floor and normal carpet cleaning modes to the rear of the head being raised.

[0022] In one embodiment, the actuator means may comprise a single actuator which can be displaced to selectively extend or retract the floor-engaging members and to selectively raise or lower the rear of the body relative to the floor surface being cleaned.

[0023] In an alternative embodiment, the actuator means may comprise a first actuator which can be displaced to selectively extend or retract the floor-engaging members and a second actuator which can be displaced to selectively raise or lower the rear of the body relative to the floor surface being cleaned. The first actuator may comprise a pedal on the head. The second actuator may comprise a rotary actuator. The first actuator switches between the hard floor cleaning mode and the normal carpet cleaning mode and thus the head is easy to use since the user normally just switches between one and the other using the first actuator, with the other actuator only being used occasionally for intensive carpet cleaning. The first actuator is also the only actuator that needs to be used during testing of the DPU.

[0024] The elongate floor-engaging members may comprise elastomeric wiper blades and/or brushes. In a preferred embodiment, the front elongate floor-engaging member comprises an elongate brush and the rear elongate floor-engaging member comprises an elastomeric wiper. The lower end of the elongate brush may comprise on or more gaps through which air can pass.

[0025] Preferably the lower ends of the elongate floor-engaging members lie in a plane which extends parallel to the floor surface when the rear of the body is raised.

[0026] Preferably the front and rear depending elongate floor-engaging members are mounted on a carrier which is displaceable relative to the body although it will be appreciated that the front and rear depending elongate floor-engaging members could be fixed relative to the body, with the bottom surface of the body being displaceable.

[0027] The body of the head may be selectively raised or lowered by respectively lowering or raising a wheel at the rear of the head.

[0028] An embodiment of the present invention will now be described by way of example only and with reference to the accompanying drawings, in which:

Figure 1 is a bottom view of a vacuum cleaner head in accordance with the present invention;

Figure 2 is a sectional view along the line ii-ii of the head Figure 1 when the head is in its hard floor cleaning mode;

Figure 3 is perspective view from one side and above of the head Figure 1 when the head is in its hard floor cleaning mode;

Figure 4 is a sectional view along the line ii-ii of the head Figure 1 when the head is in its normal carpet cleaning mode;

Figure 5 is perspective view from one side and above of the head Figure 1 when the head is in its normal carpet cleaning mode;

Figure 6 is a sectional view along the line ii-ii of the head Figure 1 when the head is in its intensive carpet cleaning mode; and

Figure 7 is perspective view from one side and above of the head Figure 1 when the head is in its intensive carpet cleaning mode.

[0029] Referring to Figures 1 to 3 of the drawings, there is shown a cleaning head in accordance with the present invention for fitting to a canister vacuum cleaner, the head comprising a body 10 and a rearwardly-extending tubular suction outlet 11 at the rear of the body 10 for releasably coupling to the distal end of a tubular wand of the cleaner. In use, a motor and fan unit in a body portion of the cleaner (not shown) draws air through the head via the wand.

[0030] The head is supported at its rear by a pair of wheels 12. The body 10 of the head comprises a one-piece shell of moulded plastics material which defines a passageway 14 that leads from the tubular suction outlet 11 to an elongate suction mouth 15 provided on the underside of the body 10. The shell of the body 10 comprises an integral floor-engaging soleplate 16 on its underside. An aesthetic hollow plastics covering (not shown) is fitted on top of the shell.

[0031] The suction mouth 15 extends transversely across almost the entire width of the of the soleplate 16 of the body 10 and is bounded at its front and rear by front and rear planar bottom surface portions of the soleplate 16. The front of the bottom surface of the soleplate 16 extends upwardly.

[0032] The front edge of the suction mouth 15 is straight and extends parallel to the front edge of the bottom surface of the soleplate 16. The rear edge of the suction mouth 15 is curved forwardly towards its outer ends on opposite sides of a straight central portion. This shape helps to maintain a uniform air velocity across the full width of the suction mouth 15.

[0033] A rib or lint picker 121 extends transversely of the body 10 across the rear planar bottom surface portion of the soleplate 16. The longitudinal profile of the rib 121 substantially follows the longitudinal profile of the rear edge of the suction mouth 15 and is separated therefrom by a region of the planar bottom surface portion of the soleplate 16. Respective opposite ends of the rib 121 meet a pair of side ribs 122, which extend forwardly along the side edge of the soleplate 16 to a point in front of the suction mouth 15.

[0034] A front depending elongate floor-engaging brush 17 is mounted to a displaceable carrier plate 13 positioned above the soleplate 16. The tip of the brush 17 may comprise cut-outs or castellations 17C. The brush 17 is disposed in front of the soleplate 16.

[0035] A rear depending elongate floor-engaging wiper 19 of elastomeric material is also mounted to the displaceable carrier plate 13. The wiper 19 extends through a slot formed along the rear edge of the soleplate 16.

[0036] Springs 18 act between the fixed soleplate 16 and the carrier plate 13 to bias the carrier plate 13 upwardly. A rotatable actuator pedal 20 is mounted on a shaft 22 which is mounted at opposite ends to brackets 21 which extend upwardly from the soleplate 16. The shaft 22 has camming surfaces 23 at opposite ends which act on formations on the carrier plate 13 to displace the carrier plate 13 upwardly and downwardly as the actuator pedal 20 is rotated between two positions. In Figures 2 and 3, the actuator pedal 20 is rotated into its clockwise position in which the carrier plate 13 is displaced downwardly against the spring bias to extend the elongate floor-engaging brush 17 and the elongate floor-engaging wiper 19 out of the body 10 to a position where they project below the bottom surface of the soleplate 16.

[0037] A rotatable actuator dial 24 is mounted to the upper surface of the body 10. Rotation of the dial 24 in the counter-clockwise direction displaces the rear wheels 12 downwardly to a point where their axis of rotation extends in substantially the same plane as the bottom of the soleplate 16. Rotation of the dial 24 in the clockwise direction displaces the rear wheels 12 upwardly to a point where the bottom of the wheels lie in substantially the same plane as the bottom of the soleplate 16. In Figures 2 and 3, the actuator dial 24 is rotated into its counter-clockwise position, so that the wheels 12 are lowered.

[0038] In use, the head (as configured in Figures 2 and 3) can be used for hard floor cleaning once the cleaner has been energised. In this mode, the rear of the body 10 is raised by the wheels 12 and the floor-engaging members 17,19 are extended to a position below the bottom surface of the soleplate 16. The forwardly and downwardly inclined attitude of the body 10 makes head easier to push over the hard floor surface F being cleaned and, since the suction mouth 15 is raised above the floor surface F, any tendency for the head to adhere the floor is alleviated. The floor-engaging members 17,19 contact the floor surface and promote the flow of air over the underlying floor surface so that a good DPU performance is achieved for hard floors. The brush of the front floor-engaging member 17 acts to promote cleaning and the cut-outs 17c allow air and dust to pass under the head.

[0039] Referring to Figures 4 and 5, in use, for normal carpet cleaning, the actuator dial 24 is rotated into its counter-clockwise position, so that the wheels 12 are lowered to raise the rear of the body 10. The actuator pedal 20 is rotated into its clockwise position in which the carrier plate 13 is displaced upwardly by the spring bias to retract the elongate floor-engaging brush 17 and the elongate floor-engaging wiper 19 into the body 10 above the bottom surface of the soleplate 16. The forwardly and downwardly inclined attitude of the body 10 again makes head easier to push over the carpet being cleaned and, since the suction mouth 15 is raised above the floor surface, any tendency for the head to adhere the carpet C is alleviated. Only the front of the bottom surface of the soleplate 16 engages the carpet and suction mouth 15 is slightly raised above the surface of the carpet C. The front of the bottom surface of the soleplate 16 acts to bend the carpet pile forwardly so that engrained dirt and dust can be drawn out of the carpet by the suction behind the front surface. In this manner a good DPU performance is achieved for carpets.

[0040] Referring to Figures 6 and 7, in use, for intensive carpet cleaning, the actuator dial 24 is rotated into its clockwise position, so that the wheels 12 are raised to lower the rear of the body 10. The actuator pedal 20 is rotated into its clockwise position in which the carrier plate 13 is displaced upwardly by the spring bias to retract the elongate floor-engaging brush 17 and the elongate floor-engaging wiper 19 into the body 10 above the bottom surface of the soleplate 16. The entire bottom surface of the soleplate 16 and the suction mouth 15 are thus in direct contact with the carpet C and both the front and rear surfaces of the soleplate 16 act to successively bend the carpet pile away from the suction mouth 15 on successive forwards and rearwards movements of the head, so that engrained dirt and dust can be drawn out of the carpet C by the suction.

[0041] On the forward stroke, the rib 121 augments dust removal as it penetrates, agitates and flicks engrained dust towards the surface of the carpet away from the influence of the suction. On the rearward stroke, the head is lifted slightly from the carpet by the angle of the wand and the displaced dust on the surface of the carpet C is drawn into the suction mouth 15 under the action of airflow and reduced agitation. The repeated backwards and forwards movement of the head brings more deeply embedded dust to the surface of the carpet C on successive strokes. The complementary shape of the rib 121 with the rear edge of the suction mouth 15 improves dust removal. The ribs 121 and 122 each contribute to maintaining a vacuum around the suction mouth 15.

[0042] Since the intensive carpet cleaning mode of use will result in some increased tractive effort, it is only intended for occasional intensive carpet cleaning with a better DPU performance than that which is achieved for normal carpet cleaning.

[0043] The present invention is simple and inexpensive in construction, yet provides a vacuum cleaner head for use on hard floors and carpet and which provides easy setting of hard floor and carpet cleaning carpet cleaning modes and unquestionable compliance with the marked energy efficiency grade of the cleaner.

Claims

1. A vacuum cleaner head comprising:

a front;

a rear;

a body having a bottom surface which defines a transversely extending suction mouth;

front and rear depending elongate floor-engaging members which extend axially of the suction mouth on respective opposite sides thereof and which are displaceable from a retracted position inside the body to an extended position below the bottom surface of the body; and

actuator means arranged for selectively extending or retracting the floor-engaging members characterised in that the actuator means is further arranged for selectively raising or lowering the rear of the body relative to the floor surface being cleaned.

2. A vacuum cleaner head as claimed in claim 1, in which the bottom surface of the body has substantially flat front and rear surface portions which respectively extend from front and rear edges of the suction mouth respectively.

3. A vacuum cleaner head as claimed in claim 1 or 2, in which the bottom surface of the body has front and rear surface portions which respectively extend from front and rear edges of the suction mouth respectively, a rib extending across the rear portion behind the suction mouth.

4. A vacuum cleaner head as claimed in any preceding claim, in which the bottom surface of the body has front and rear surface portions which respectively extend from front and rear edges of the suction mouth respectively, wherein a lint picker comprising tufts of fine fibres extends across the rear portion behind the suction mouth.

5. A vacuum cleaner head as claimed in any preceding claim, in which the bottom surface of the body has front and rear surface portions which respectively extend from front and rear edges of the suction mouth respectively, the front of the bottom surface of the body being inclined upwardly and away from the front edges of the suction mouth to provide a surface on which the head can ride in use.

6. A vacuum cleaner head as claimed in any preceding claim, in which the actuator means comprises a first actuator which can be displaced to selectively extend or retract the floor-engaging members and a second actuator which can be displaced to selectively raise or lower the rear of the body relative to the floor surface being cleaned.

7. A vacuum cleaner head as claimed in claim 6, in which the first actuator comprises a pedal on the head.

8. A vacuum cleaner head as claimed in claim 6 or 7, in which the second actuator comprises a rotary actuator.

9. A vacuum cleaner head as claimed in any preceding claim, in which the elongate floor-engaging members may comprise elastomeric wiper blades and/or brushes.

10. A vacuum cleaner head as claimed in any preceding claim, in the front elongate floor-engaging member comprises an elongate brush and the rear elongate floor-engaging member comprises an elastomeric wiper.

11. A vacuum cleaner head as claimed in any preceding claim, in which the front and rear depending elongate floor-engaging members are mounted on a carrier which is displaceable relative to the body.

12. A vacuum cleaner head as claimed in any preceding claim, in which the body of the head is selectively raised or lowered by respectively lowering or raising a wheel at the rear of the head.

Drawing