GB2128583A

GB2128583A - Method and apparatus for handling articles

Info

Publication number: GB2128583A
Application number: GB08229914A
Authority: GB
Inventors: David Underhill
Original assignee: Handling Design & Construction
Current assignee: Handling Design & Construction
Priority date: 1982-10-20
Filing date: 1982-10-20
Publication date: 1984-05-02

Abstract

Apparatus 10 for handling articles such as boxes comprises a mobile frame 12 mounted on ground wheels 14, 16 and a mast 18 carrying article gripping apparatus 20 connected to a lifting mechanism 22. Gripping apparatus 20 comprises a tension member 38 to extend round three sides of box 36 and a flat rigid support member 40 against which box 36 is held by the tension member. The tension member is tightened around the box and the lifting mechanism raises support member 40 and the tension member. The lifting movement causes the tension member to effect a squeezing action between the box and the support member 40. <IMAGE>

Description

SPECIFICATION Method and apparatus for handling articles This invention relates to a method and apparatus for handling articles. The invention is particularly applicable to the handling of rectangular boxes but is also applicable to articles of other shapes such as drums, and in some cases to articles of irregular shape.

The invention also provides atensioning mechanism forming part of the article handling apparatus but which is also applicable in other situations and mechanisms, such as the tensioning of flexible side sheets in load-carrying vehicles such as articulated trucks.

The invention is particularly, but not exclusively, applicable to article handling apparatus for lifting and/or lowering and/or placing articles, so as to execute article handling operations which are currently carried out by means of fork lift trucks and associated pallets.

Problems arising from the use of conventional fork lift trucks and associated pallets arise largely from the requirement for the articles being handled to be initially placed on a pallet so that the forks of the fork lift truck can enter the pallet underneath the article and the pallet and the article can then be lifted. This system requires the provision of large numbers of relatively expensive pallets and also raises the problem of how to initially deposit articles onto the pallets. Moreover, an associated problem is that, in addition to the initial cost of the pallets, it is found that large numbers of pallets require to be replaced due to losses and breakage.

A related problem, and one connected to some extent with the problem of how to place articles onto the pallets prior to their handling on a fork lift truck, is the question of manual handling of relatively heavy articles. Heaith and safety at work regulations are providing upper limits for the loads to be manually handled by employees, and these regulations are imposing further difficulties in relation to the handling of articles.

An aim of the present invention is to provide a method and apparatus for handling articles offering improvements in relation to one or more of the problems identified above.

According to one aspect of the present invention there is provided a method of handling an article comprising engaging sides of the article by first and second gripping means and effecting relative movement between said first and second gripping means whereby the article is gripped therebetween.

Preferably, the method includes the step of initially engaging the first and second gripping means with opposite sides of the article. In a subsequent step of the method, the second gripping means may have a lifting force applied thereto whereby relative movement between the first and second gripping means under the action of said lifting force and the weight of the article provides said gripping action.

The gripping means may comprise an adjustable tension member, and the method may include the step of tensioning the adjustable tension member so as to engage the first and second gripping means with the article.

The first and second gripping means may be provided on mobile article handling apparatus having spaced support legs mounted on ground wheels, and the method may include the step of positioning an article to be lifted between said support legs prior to initial engagement of the article by said first and second gripping means.

According to another aspect of the invention there is provided article handling apparatus comprising first and second gripping means for engagement with sides of an article to be handled, the gripping means being interconnected and moveable relative to each other, the arrangement being such that relative movement of the gripping means causes a gripping action between the gripping means and the article to be handled.

Preferably, a friction surface is provided for engagement with an article to be handled on at least one of the gripping means, and preferably on both the first and second gripping means.

The gripping means may be pivotally interconnected for said relative movement or may be connected by means of flexible connecting means. Alternatively, where one of the gripping means is itself flexible, then no additional provision is required to accommodate the relative movement of the gripping means.

The first gripping means may comprise a tension member to extend round at least a portion of the periphery of an article to be handled. The tension member may comprise a length of webbing or like woven textile or metallic carcase material covered with or embedded in a natural or synthetic polymeric or elastomeric material such as natural or synthetic rubber.

A tensioning mechanism is preferably provided for the tension member. The tensioning mechanism may be manually operable and may comprise a lever mechanism. The lever mechanism may comprise a lever member formed with a slot or opening through which, in use, the tension member extends. The lever member may be provided with means whereby the slot is openable to release the tension member by means of a moveable slot-edge member. The slot-edge member may be spring-biased towards its tension member-gripping position. The lever of the lever mechanism may be mounted as to be moveable between a released position and a tensioned position, the arrangement being such that the tension member is kinked in passing through the slot in the lever member in the tensioned position of the lever member.

Preferably the second gripping means comprise a support member to support an article being handled against the gripping action of the first gripping means. The dimensions of the support member are preferably such that, in the working attitude of the apparatus, the lower edge of the support member is in the region of the lowest normal working position of the first gripping means. The support member may be in the form of a flat board for engagement with flat articles such as boxes. Alternatively, the support member may be profiled to accommodate articles of other shapes. For example, the support member may be formed with a part-cylindrical surface to accommodate a drum-shaped article or the like.

The invention also provides mobile article handling apparatus wherein the first and second gripping means are mounted on a mast and a lifting mechanism is connected to the second gripping means. The mobile apparatus may comprise spaced support legs having groundengageable wheels.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which: Fig. 1 shows a side elevation view of article handling apparatus according to the invention; Fig. 2 shows a plan view of the apparatus of Fig. 1; and Fig. 3 shows, on a much larger scale, a detailed cross-sectional view of a tensioning mechanism for a flexible tension member forming part of gripping means for engaging and gripping the box seen in Figs. 1 and 2.

As shown in the drawings, article handling apparatus 10 comprises a mobile frame 12 mounted on ground wheels 14, 16, and an upwardly extending mast 18 mounted on the frame and carrying article gripping apparatus 20, the article gripping apparatus being connected to.

a lift and lower mechanism 22 whereby the gripping apparatus and the articles gripped thereby can be lifted and lowered.

Frame 12 comprises a rear frame portion 24 and forwardly projecting support legs 26, 28. Rear frame portion 24 is supported on ground wheels 14 which are connected thereto by castors 30 so as to be self-steering. Ground wheels 14 are journalled in support legs 26, 28 in fixed attitudes relative thereto.

Article handling apparatus 10 is of a size and adapted to be manually manoeuvred so as to be usable, for example, for handling boxes within a warehouse or factory. The apparatus is able to engage and grip and article, and by actuation of the lift mechanism 22 can lift the article from the ground, whereupon the apparatus 10 can be manually manoeuvred to a new position where the mechanism 22 can be actuated to cause the article to be deposited.

Mobile frame 12 serves to support mast 18, article gripping apparatus 20 and the lift and lower mechanism 22, and maybe of any suitable form.

For example, the frame may be considerably larger for the purposes of a self-propelled article handling apparatus comparable in its operational capacity to a fork lift truck, and in such a case the ground wheels 14, 1 6 will be arranged to be steerable.

Mast 18 and the lift and lower mechanism 22 will not be described in detail since considerable modification thereof may be effected without departing from the scope of the present invention.

The mast serves to support the article gripping apparatus 20 which is connected to the lift and lower mechanism 22, and the structures 1 8 and 22 may be of fairly conventional form, adapted from the comparable mechanisms of a fork lift truck or the like. The lift and lower mechanism is usually operated by an electrical storage battery, but other sources of power may be adapted for the purpose.

Article gripping apparatus 20 will now be described in greater detail.

The article gripping apparatus comprises first and second gripping means 22, 34 respectively for engagement with opposite sides of an article to be lifted, such as a box 36. The first and second gripping means 32, 34 are inter-connected and moveable relative to each other, the arrangement being such that relative movement between the gripping means under the action of a lifting force applied to one of the gripping members and/or the weight of the article being handled effects a gripping action on the article between the gripping means.

The gripping means are provided with friction surfaces for engagement with opposite sides of an article being handled, and are pivotally interconnected (in addition to the first gripping means being of flexible construction) so as to permit the above-mentioned relative movement of the gripping means.

The first gripping means 32 comprises a tension member 38 to extend round three sides of box 36. The second gripping means 34 comprises a flat rigid support member 40 against which box 36 is held by tension member 38. The tension member is pivotally connected at one end to one side of support member 40 and extends round three sides of box 36 and is then adjustably connected to the other side of support member 40 through a tensioning mechanism 42.

Tension member 38 is connected at its opposite ends to opposite sides of support member 40. The connection between the tension member and the support member is, in each case, through a pivot pin (not shown) defining a pair of pivot axes extending generally horizontally and substantially coaxial ly. The pivotal connection between the tension member and the support member permits relative angular movement between these members about the common pivot axis 44. In the present embodiment, the provision of a flexible tension member renders the provision of a pivotal connection between the first and second gripping means, an optional feature.

Moreover, it will be appreciated that it is by no means essential for the two pivot axes to be coaxial.

At one end of tension member 38 it is provided with a swaged-on metallic end member (not shown) through which the horizontal pivot pin extends. At the other end of the tension member, tensioning mechanism 42 is connected to the tension member in a manner to be described and is likewise connected to support member 40 by a pivot pin (not shown) extending through the tensioning mechanism.

It will now be understood that by looping the tension member 38 around box 36 andtightening-: the tension member, the box willbe held- against support member 40 while resting on the ground: 46.

Tension member 38 comprises a length; of conveyor belting. having. a woven or unwoventextile or metallic carease embedded in a natural or synthetic elastomeric or other polymeric body material. For example, the tensron member may be of width from 1 centimetre to 10 éntimetres (measured between its upper and- lower edges 48, 50) and of thicknessfrom 2 to 8 millimetres, being of natural or synthetic rubber conveyor belting with a high friction flat rubber inner surface for engagement with box 36.

Support member 40 is reetangular in form and formed as a stiff wooden structure, but any other suitable material whether of a metallic or a plastie material or a composite material may be employed. The support member is provided on its surface facing box 36 with a friction surface 52 provided by a layer of elastomeric material (such as conveyor belting or the like) for engagement with box 36 The friction surface may be provided over the entire surface of the support member facing the article to be lifted, or only over a portion thereof.

Tensioning mechanism 42 is illustrated in Fig. 3 and comprises a manually operable lever mechanism including a lever 54 pivotally mounted on a mounting plate 56 which is itself connected by the pivot pin (not shown) to support member 40.

Tension member 38 extends through a slot 58 formed in lever 54, the slot being openable to release the tension member by means of a moveable slot-edge member 60, the other edge of the slot being defined by a fixed slot-edge member 62, both said edge members being mounted on lever 54 for movement therewith.

Moveable slot-edge member 60 is mounted for pivotal movement about an axis 64 and biased by a spring 66 to the position shown in Fig. 3. The moveable slot-edge member is manually releasable by finger pressure (turning the slotedge member anti-clockwise as seen in Fig. 3) to open slot 58 and thereby allow lever 54 to be pivotally moved about its axis 68 from the tensioned position shown in Fig.3 anti-cloekwise (as seen in Fig. 3) to a released position (not shown). In the tensioned position shown in Fig-. 3- it will be noted that the tension member is kinked as it passes through sI-ot 58 and: thereby firmly frictionally held between the moveable and fixed slot-edge members 60, 6-2.

In use, apparatus 10 is manoeuvred in relation to box 36 so that legs 26 straddle the box, whereupon tension member 38- is looped over the box and the tension member pulled by its free end through slor 58 with moveable slot-edge member 60 released by finger pressure. When the tension member is tight, the slot-edge member is released and lever 54 is pivoted clockwise about its axis 68 to the tensioned position shown in Fig. 3, whereupon box 36 is firmly held against the friction surface 52 of support member 40.

Lifting mechanism 22 is then activated and a; lifting thrust is applied to support member 40 thereby tending to lift both the support member and tension member 38, and hence box 36.

If box 36 is somewhat heavy and there is anytendency for it to slip relative to the friction surface 52 of support member 40, by virtue of the friction between tension member 38 and the box the tension member will be pulled downwards at its outer end (anti-clockwise movement about axis 44 in Fig. 1) thereby increasing the force holdingthe box against friction surface 52 and effectively increasing the grip on the box between the tension member 38 nd support member 40.

In other words, any initial tendency of the box to slip relative to the support member causes the tension member to hold the box more firmly against the support member until the friction therebetween is sufficient for the box to be lifted.

The result of this self-servo action is that even very heavy articles can be readily lifted with a minimum of slip between the support member and the tension member.

Among modifications which could be made in the above-described embodiment without departing from the scope of the invention are the following: 1. The use of a modified support member. For example, the support member need not provide support or reaction over an entire surface of an article being handled. The support member may be formed in two or more portions, a lower portion to exert a reaction force substantially opposite the outer portion of the tension member 38 in the latter's lowermost working position, and an upper portion secured to the opposite ends of the tension member.

2. The use of modified friction or lower-friction surfaces on the first and second gripping means 32,24.

3. The use, in place of tension member 38, of a first gripping means comprising, for example, a gripping member for engagement with the outer face 70 of box 36, the gripping member being connected in any suitable way at its opposite ends to the support member, for example by rigid arms or flexible tension members or wires, or by any suitable length-adjustment means. In this manner with suitable pivotal connection between the gripping member and its mountings, the first gripping means need not be flexible in form.

4. The use of a support member or second gripping means modified to accommodate articles of other shapes, for example the support member may be part-cylindrical in form to engage and grip drums and the like.

5. The tensioning mechanism 42 may be employed for tensioning other flexible tension members in other situations, such as in the mounting of flexible covers on road vehicles and trucks.

Among the advantages provided by the embodiment of the invention described above are the simple and relatively inexpensive and rugged structure provided for gripping the article to be lifted. Moreover, this structure is able to lift articles without the use of a pallet or any equivalent device, so that handling of articles does not require a preliminary pallet-placement step.

The article gripping apparatus is easily connected to a lifting mechanism whether of conventional form or otherwise, so as to provide lifting apparatus, for example, in a form similar to that of a fork lift truck, which thereby incorporates the advantages of the article gripping apparatus in a mobile machine suitable for use in factories, warehouses and elsewhere. The tensioning mechanism for the first gripping means is of simple and reliable form and is easily used and, moreover, is adaptable to other situations and mechanisms.

Claims

1. A method of handling an article comprising engaging sides of the article by first and second gripping means and effecting relative movement between said first and second gripping means whereby the article is gripped therebetween.

2. A method according to claim 1 including the step of initially engaging the first and second gripping means with opposite sides of the article.

3. A method according to claim 2 including the subsequent step of applying a lifting force to the second gripping means whereby relative movement between the first and second gripping means under the action of said lifting force and the weight of the article provides said gripping action.

4. A method according to any one of the preceding claims wherein said gripping means comprises an adjustable tension member, and the method includes the step of tensioning the adjustable tension member so as to engage the first and second gripping means with the article.

5. A method according to any one of the preceding claims wherein said first and second gripping means are provided on mobile article handling apparatus having spaced support legs mounted on ground wheels, and the method includes the step of positioning an article to be lifted between said support legs prior to initial engagement of the article by said first and second gripping means.

6. Article handling apparatus comprising first and second gripping means for engagement with sides of an article to be handled, the gripping means being interconnected and movable relative to each other, the arrangement being such that relative movement of the gripping means causes a gripping action between the gripping means and the article to be handled.

7. Apparatus according to claim 6 wherein a friction surface is provided for engagement with an article to be handled on at least one of the gripping means.

8. Apparatus according to claim 7 wherein said friction surface is provided for engagement with an article to be handled dn both the first and second gripping means.

9. Apparatus according to any one of claims 6 to 8 wherein the gripping means are pivotally inter-connected for said relative movement.

1 0. Apparatus according to any one of claims 6 to 8 wherein said gripping means are inter connected by means of flexible connecting means.

11. Apparatus according to any one of claims 6 to 8 wherein one of the gripping means is itself flexible.

12. Apparatus according to claim 11 wherein the first gripping means comprises a tension member to extend round at least a portion of the periphery of an article to be handled.

13. Apparatus according to claim 12 wherein said tension member comprises a length of webbing or like woven textile or metallic carcase material covered with or embedded in a natural or synthetic polymeric or elastomeric material such as natural or synthetic rubber.

14. Apparatus accordng to claim 12 or claim 1 3 wherein a tensioning mechanism is provided for the tension member

1 5. Apparatus according to claim 14 wherein said tensioning mechanism is manually operable and comprises a lever mechanism.

1 6. Apparatus according to claim 1 5 wherein said lever mechanism comprises a lever member formed with a slot or opening through which, in use, the tension member extends.

1 7. Apparatus according to claim 16 wherein said lever member is provided with means whereby the slot is openable to release the tension member by means of a movable slot edge member.

18. Apparatus according to claim 17 wherein said slot edge member is spring biased towards its tension member-gripping position.

1 9. Apparatus according to claim 1 8 wherein said lever of the lever mechanism is mounted so as to be movable between a released position and a tensioned position, the arrangement being such that the tension member is kinked in passing through the slot in the lever member in the tensioned position of the lever member.

20. Apparatus according to any one of the preceding claims wherein the second gripping means comprises a support member to support an article being handled against the gripping action of the first gripping means.

21. Apparatus according to claim 20 wherein the dimensions of the support member are such that, in the working attitude of the apparatus, the lower edge of the support member is in the region of the lowest normal working position of the first gripping means.

22. Apparatus according to claim 21 or claim 20 wherein said support member is in the form of a flat board for engagement with flat articles such as boxes.

23. Apparatus according to claim 20 or claim 21 wherein said support member is profiled to accommodate articles having shapes corresponding thereto.

24. Mobile article handling apparatus according to any one of claims 6 to 23 wherein said first and second gripping means are mounted on a mask and a lifting mechanism is connected to the second gripping means.

25. Apparatus according to claim 24 wherein said mobile apparatus comprises spaced support legs having ground engageable wheels.

26. A method of handling an article substantially as described herein with reference to the accompanying drawings.

27. Article handling apparatus substantially as described herein with reference to the accompanying drawings.

28. A method of handling an article comprising any novel step or combination of steps disclosed herein.

29. Article handling apparatus comprising any novel feature or combination of features disclosed herein.

30. A tensioning mechanism for a flexible tension member, the tensioning mechanism comprising the features set forth in any one of claims 14 to 19.