GB2031845A - A load handling unit - Google Patents

Abstract

A load handling unit for use with raising and lowering equipment such as forklift trucks or cranes comprises a pallet 10 on which a container 12 is mounted for tilting movement via a pivotal mounting 28, 30 which preferably allows the container to be readily separated from the pallet thus freeing the pallet for use with other similar containers. The container is provided with legs which space its base above floor level so that the container is free standing independently of the pallet. A locking mechanism 42 is provided so as to engage a projection 40 on the container to hold the container in a generally horizontal attitude. <IMAGE>

Description

SPECIFICATION A load handling unit This invention relates to a load handling unit for use with raising and lowering equipment such as forklift trucks and cranes.

One of the limitations of conventional forklift trucks is their inability to tilt the load mounted on the carriage thereof through a substantial angle as will be required for example when the contents of a load receiving container are to be discharged by tipping the container. This limitation is overcome in a known arrangement using a specially designed container which has curved surfaces engaging a pallet structure which is adapted to be engaged by a forklift carriage so that the container can rock (underthe control of guides) on said curved surfaces between horizontal and tilted positions. Such containers are permanently mounted on the associated support struture. When the container is parked, it rests on and is supported wholly by the pallet which, in turn, engages the ground.

Besides being relatively complex to manufacture in view of the need for curved rocking surfaces and guides, such a construction is disadvantageous especially if a number of such units have to be employed as would often be the case, especially in factories, where each container unit may have to serve as a temporary storage container as well as a transport container. For example, such a container unit may have to be used as a collection container for components being produced by one machine and then transported to a second location to provide a stock of the components for use in an assembly step performed at another machine. Subsequently, when the stock of components has been used up and the container unit becomes available again, it may be required for collection of swarm for example which is to be transported to and discharged at a swarf disposal location.

The object of the present invention is to provide a load handling unit which overcomes the above drawbacks.

According to one aspect of the present invention we provide a load-handling unit for use with raising and lowering equipment, said unit cmprising a load-receiver and a carrier forming a platform on which the load receiver can be mounted for tilting movement about a generally horizontal axis from a generally horizontal attitude to a tilted attitude, means being provided for releasably retaining the load-receiver in said generally horizontal attitude when carried by the carrier, the load-receiver having a formation located beneath the underside thereof which when the carrier is located beneath the load receiver with the latter in a generally horizontal attitude, can be brought into engagement with a formation provided on the carrier by vertically displacing the carrier towards the receiver, said formations, when interengaged, forming a fulcrum arrangement for said tilting movement of the load receiver on the carrier, the carrier being adapted for connection to said raising and lowering equipment.

Preferably the load receiver includes a base and is provided with ground engageable legs which space its base above ground level to an extent sufficient to allow entry of the carrier into the space beneath said base whereby said fulcrum formations can be brought into engagement while the load receiver is free standing.

Thus, with a unit in accordance with said one aspect of the invention the carrier and the load receiver are readily separable and a single carrier can be used with a number of load receivers. For example, when a load receiver is to be used for storage or collection purposes as opposed to transportation and discharge of material, it can be separated from its carrier which is then freed for use with any other available load receiver.

The retaining means is preferably automatically operable in response to coupling of said fulcrum formations and one specially advantageous form of retaining means will be disclosed herein which, though intended primarily for use as part of a load handling unit according to the invention, may be applicable to other situations in which automatic locking of two components is required.

According to another aspect of the invention we provide a load-handling unit for use with a forklift vehicle having a pair of lifting arms, said unit comprising a pallet adapted to be engaged by the lifting arms of the vehicle and a container which is pivotally connected to the pal let for tilting movement about a generally horizontal axis formed by the pivotal connection(s) between the pallet and the container.

Preferably the container is provided with legs which enable the container to be free-standing independently of the pallet in contrast with the known arrangement where the pallet supported the container even when the unit is floor standing.

Further advantages of the invention will become apparent from the following description of various embodiments which will be described by way of example only with reference to the accompanying drawings in which: Figure lisa side view of a container forming part of the load handling unit in accordance with the invention; Figure 2 is an end view of the container; Figure 3 is a side view of the pallet of the load handling unit; Figure 4 is a end view of the pallet; Figure 5 is a side view of the load handling unit with the container and pallet coupled together and showing the container in a tilted position relative to the pallet; Figures 6and 7 are side views of an automatic locking mechanism forming part of the load hand ling unit, the mechanism being shown in its reieas ing and locking positions respectively; and Figure 8 is a side view of a modified form of container.

Referring now to the drawings, the load handling unit comprises a pallet 10 and a container 12. The container may be open topped and has side walls 14, rear end walls 16, base 18 and an inclined wall 20.

The side walls 14 extend below the base 18 to form legs which space the base 18 above ground level.

The forward end of the container is open to allow discharge of the contents thereof. This end may be provided with a hinged door and door catch (as in the embodiments of Figure 8) if desired.

The pallet 10 comprises two spaced parallel inverted channel-section members 22 bridged by cross members 24, 26 and 28 to form a platform for the container 12. The cross member 28 comprises a round section tube or bar located immediately adjacent the forward ends of the channels 22. The width and height of the pallet 10 is such that it can be introduced into the space between the side walls 14 and the base 18 of the container 12. The bar 28 is intended to be interengaged with a transverse channel 30 provided on the underside of the container base 18 to form a fulcrum about which the container can be tilted, see Figure 5.

The channel 30 is defined by spaced side walls 32, 34. The rear side wall 32 is reinforced by gussets 36 and has a flange 38 which partly spans the gap between the side walls 32, 34 to form a restricted opening through which the bar 28 can enter the channel 30. When the bar 28 is engaged within the channel 30, the container can be supported by the pallet in a generally horizontal attitude with the base 18 resting on the bar 28 and cross member 26. To retain the container in this attitude, the container is provided with a projection 40 extending from its rear end wall and the pallet is provided with a releasable locking mechanism 42 which will be described below with reference to Figures 6 and 7.The arrangement is conveniently such that, when the locking mechanism is operated to release the projection 40, the container tilts forwardly to the position shown in Figure 5 either automatically or preferably in response to tilting of the forklift carriage. In the former case, automatic tilting can be achieved by approprate design of the container and pallet and, in particular, appropriate positioning of the channel 30 lengthwise os the container so that the container is not in a position of stability when mounted on the pallet in the general horizontal attitude. Of course, the container will be stable in the generally horizontai attitude when it is floor-standing. In the latter case, when in the horizontal attitude, the container will be stable on the pallet even when the pallet is raised.

Forward tilting of the container is limited by suitable stop means which, in the illustrated embodi ment, comprise an extension 35 of the side wall 34 and an inclined abutment plate 44 at the front end of the pallet. Reinforcement for the extension 35 and also the side walls 14 is provided by a cross member 46 bridging the side walls 14.

The pallet is designed so that, in use, it can be engaged with the arms of a forklift truck, the forklift arms being received in channels 22. To mount the container on the forklift carriage, the pallet is first picked up by the forklift carriage in conventional fashion and is then manouvered into the space beneath the floor standing container so that the bar 28 is in registry with the restricted opening of the channel 30 and the locking mechanism 42 is in registry with the projection 40. The pallet is then raised so that the mechanism 42 automatically engages and locks the projection 40 and the bar 28 enters the channel 30.The container is now coupled with the forklift carriage via the pallet and can be dismounted simply by lowering the pallet until the container engages the ground, releasing the locking mechanism 42 and continuing to lower the pallet, possibly with some accompanying forward movement, to disengage the bar 28 from the channel 30.

When the container is coupled to the pallet as described above, it can be readily tilted to the position of Figure 5, for example to discharge a load via the open forward end of the container, simply by releasing the locking mechanism 42. This may be effected manually or there may be some linkage enabling actuating of the locking mechanism to be effected from a remote position, e.g. the driving seat of a forklift truck. If a controlled tilting of the container is desired, the pallet may be provided with a fluid powered ram or other adjustment mechanism (not shown) which can be releasably coupled to the container, e.g. via a lug or the like on the base 18 and quick release pins. Again, such an adjustment mechanism may be controlled remotely for example by means of a control valve accessible from the driving seat of the forklift truck.Conveniently the angle of inclination of the wall 20 is such that when the container is fully tilted, it is downwardly inclined in the discharge direction.

The side walls of the container are provided with brackets or the like 48 to enable an extension unit (not shown) to be fitted and secured in nested relation to the top of the container in order to extend the side walls 14 and end wall 16 thereby increasing the storage capacity of the container. The extension unit may also include a hinged door to close the discharge end of the container.

In some circumstances, it may be desirable to park the container in a tilted attitude so as to facilitate access to the contents thereof. For this purpose, the side walls 14 may include inclined edge portions 50 on which the container can be rested at ground level, as shown in Figure 8. To stabilise the container in such circumstances, support legs 52 may be provided on each side wall 14. The support legs 52 may be pivoted at 54 to brackets 56 to enable the legs 52 to be swung from a stowed position as shown in dotted outline to the extended ground engaging position shown in solid outline. In addition to the stablising legs, the embodiment of Figure 8 is also provided with a hinged door 58 and releasable catch 60 for maintaining the door closed.

Referring now to Figures 6 and 7, the automatic locking mechanism 42 comprises a pair of vertically extending plates 64 (on one of which is shown) located in spaced opposed relation and mounted on the cross member 24 below the projection 40. These plates are formed with an upwardly opening mouth 66 for reception of the projection 40, the mouth 66 being tapered downwardly to provide a iead-in to a narrow section 68 which receives the projection 40 as a snug fit. A bifurcated rotary bolt 70 is pivotally mounted at 72 between the plates 64 for pivotal movement between the positions shown in Figures 6 and 7. In the position of Figure 7, a limb 74 of the bolt extends across the mouth 66 so as to trap the projection 40 in the section 68.The bolt is maintained in this position by a pawl formation 76 which forms an extension of an actuating lever 78 which is pivoted at 80 between the plates 64. Angular movement of the actuator 80 and hence the pawl 76 is, in turn, prevented by a locking sleeve 82 which is slidable along the actuator 78 and engages in slots 84 in the plates 64.

To release the locking mechanism and hence free the projection 40, the sleeve 82 is drawn along the actuator 80 and out of engagement with the slots 84 and the actuator is turned counterclockwise (as seen in Figure 7) so asto rotate the bolt 70 to the Figure 6 position by cooperation between the actuator 78 and the lower limb 88. Continued rotation of the bolts 70 eventually brings a heel portion 90 thereof into engagement with a notch 92 in the actuator 78 thereby maintaining the bolt and actuator in the Figure 6 position. In this position, the limb 88 overlies the section 68 of the mouth 66.

When the projection 40 is reintroduced into the mouth 66, it encounters the limb 88 and by a camiaction displaces it downwardly thereby rotating the bolt 70 and freeing it from the actuator 78 which is likewise freed for clockwise pivoting. Thus, on entering the section 68 the projection rotates the bolt until the limb 74 traps it in the section 68. At this time, the actuator will have been pivoted to the Figure 7 position and on reaching that position, the sleeve 82 slides back into engagement with the slots 84 so as to lock the bolt against rotation. Thus entry of the projection 40 into the mouth section 66 causes automatic operation of the locking mechanism 42.

Although the invention has been described above with reference to a load handling unit for a forklift truck, the invention is applicable to other forms of raising and lowering equipment. For example, the load handling unit of the invention may be used in conjunction with a crane in which case the pallet will include structural framework extending over the top of the container to provide an anchorage point or points (for connction to the crane suspension hook for example) located above the container and at a position such that the suspension point or points are at least approximately in the same vertical line or plane as the centre of gravity of the load handling unit.

Claims (28)

1. A load-handling unit for use with raising and lowering equipment, said unit comprising a loadreceiver and a carrier forming a platform on which the load receiver can be mounted for tilting movement about a generally horizontal axis from a generally horizontal attitude to a tilted attitude, means being provided for releasably retaining the load-receiver in said generally horizontal attitude when carried by the carrier, the load-receiver having a formation located beneath the underside thereof which, when the carrier is located beneath the load receiver with the latter in a generally horizontal attitude, can be brought into engagement with a formation provided on the carrier by vertically displacing the carrier towards the receiver, said formations, when interengaged, forming a fulcrum arrangement for said tilting movement of the loadreceiver on the carrier, the carrier being adapted for connection to said raising and lowering equipment.

2. A unit as claimed in Claim 1 in which the arrangement is such that when said retaining means is released the load receiver tilts from said generally horizontal attitude to a tilted attitude either automatically or in response to tilting of said carrier.

3. A unit as claimed in Claim 1 or 2 in which said retaining means is operable automatically to engage the loadd-receiver when said formations are brought into engagement.

4. A unit as claimed in any one of Claims 1-3 in which the load-receiver includes a base and is provided with ground-engageable legs which space its base above ground level to an extent sufficient to allow entry of their carrier into the space beneath said base whereby said fulcrum formations can be brought into engagement while the load-receiver is free standing.

5. A unit as claimed in any one of Claims 1-4 in which said formations are so arranged that they maintain the receiver captive to the carrier during said tilting movement but allow the receiver to be separated from the carrier when in said generally horizontal attitude, separation being effected by relatively displacing the receiver and carrier away from each other in a generally vertical direction.

6. A unit as claimed in Claim 5 in which said formations comprise a round-section bar on the carrier and a channel on the underside of the receiver, the channel having a restricted opening which allows entry or withdrawal of said bar when the receiver is in the generally horizontal attitude but which is blocked by part of the carrier when the receiver is tilted thereby maintaining the receiver captive to the carrier.

7. A unit as claimed in Claim 6 in which said channel as spaced side walls and a flange partly spanning the gap therebetween to form said restricted opening.

8. A unit as claimed in any one of Claims 1-7 in which said receiver and carrier have co-operating abutment surfaces which limit the extent of tilting of the receiver.

9. A unit as claimed in Claim 8 when appendant to Claim 7 in which said bar is mounted immediately adjacent one end of the carrier and in which one of said side walls fthe channel is provided with an extension which, in an extreme tilted position of the receiver, abuts the end of the carrier.

10. A unit as claimed in any one of Claims 1-9 including means for controlling the tilted attitude of the receiver.

11. A unit as claimed in any one of Claims 1-10 in which the receiver has inclined ground-engageable surfaces enabling the receiver to be stood at ground level in a tilted attitude, means being provided to support the receiver in such attitude.

12. A unit as claimed in Claim 4 or any one of Claims 5-11 when appendent to Claim 4 in which the load receiver has side walls which extend below said base to form said legs.

13. A unit as claimed in Claim 12 when appen dent to Claim 11 in which said side walls have lower edges which run generally parallel to said base and edges which are inclined to said base to form said inclined ground-engageable surfaces.

14. A unit as claimed in Claims 11 or 13 in which said supporting means comprise legs located at opposite sides of the receiver and movable between stowed and extended ground-engaging positions.

15. A unit as claimed in Claim 8 or 9 in which the receiver has a generally horizontal base and an inclined chute-like surface extending upwardly from said base towards a discharge opening at one end of the receiver, the arrangement being such that when the receiver is in an extreme tilted position defined by said abutment surfaces, said chute-like surface is downwardly inclined towards said discharge opening.

16. A unit as claimed in ay one of Claims 1-15 in which the raising and lowering equipment is of the fork lift type and in which the carrier is in the form of a pallet.

17. A unit as claimed in any one of Claims 1 - 15 in which said equipment is a crane and in which the carrier is adapted to be connected to the crane at a point above the receiver and intermediate the ends of the receiver.

18. A unit as claimed in Claim 3 in which said load receiver is provided with a projection for registry with the retaining means when the fulcrum formations are interengaged.

19. The retaining means of the unit claimed in Claim 18, said retaining means comprising a mouth for reception of said projection, a bifurcated rotary bolt which is displaced by the projection into a locking position as the projection enters said mouth to trap the projection between the limbs of the bolt, a pawl co-operable with the bolt to retain it in the locking position, a lever with which the pawl is fast, the lever being turned to a predetermined position by the bolt as the latter moves to its locking position, and automatic detent means for holding the lever in said predetermined position thereby preventing angular movement of the lever and, via said pawl, the bolt, the detent means being releasable to enable the lever to be used to rotate the bolt to its releasing position whereupon the bolt is held in said releasing position by further detent means which are disabled in response to displacement of the bolt upon re-entry of said projections into said mouth.

20. The retaining means as claimed in Claim 19 in which the first mentioned detent means comprises an element slideably mounted on the lever for movement under gravity into a slot provided in a housing which affords said mouth.

21. The retaining means as claimed in Claim 19 or 20 in which said further detent means comprises a heel portion on said bolt and a notch in said lever for reception of the heel portion when the bolt is in the releasing position.

22. A load-handling unit for use with a forklift vehicle having a pair of lifting arms, said unit comprising a pallet adapted to be engaged by the lifting arms of the vehicle and a container which is pivotally connected to the pallet for tilting movement about a generally horizontal axis formed by the pivotal connection(s) between the pallet and the container.

23. A unit as claimed in Claim 22, the pivotal connection(s) being so arranged that, when the container is floor standing, the pallet can be separated from the container.

24. A unit as claimed in Claim 22, the pivotal connection(s) being arranged to maintain said container permanently captive to the pallet.

25. A unit as claimed in Claim 23 or 24 in which the container is provided with legs which space its base above floor level when the container is floor.

standing so that the pallet can be introduced beneth the base of the container.

26. A unit as claimed in any one of Claims 22-25 in which the pallet and container are provided with co-operating elements of a latching device for restraining the container against pivoting on the pallet.

27. A unit as claimed in Claim 26 in which said latching device is automatically operable to effect latching when said co-operating latching elements are brought into registry with each other.

28. A load handling unit substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.