IES77047B2 - Improvements relating to forklift trucks - Google Patents

Abstract

A mounting system (1) for mounting a forklift truck (2) on a carrier vehicle chassis (3) has a receiver shoe (4) for mounting on the chassis (3) and a complementary releasably interengagable carrier head (5) on the forklift truck (2). Locking pins (18,19) on the carrier head (5) are engagable with associated hooks and lugs on the receiver shoe (4). A ram operated locking bolt (20) releasably locks the carrier head (5) on the receiver shoe (4).

Description

This invention relates to forklift trucks, and in particular to a mounting system for mounting a forklift truck in piggy-back fashion on a carrier vehicle chassis. s For mounting a forklift truck in piggy-back fashion on a carrier vehicle chassis it is known to provide sockets or tubes at the rear end of the chassis which are engageable by tines of the forklift truck to lift and support the forklift truck at a rear end of the vehicle. For improved support it is desirable to provide wheel plates on which front wheels of the forklift fit when mounted on the vehicle chassis to relieve strain on the forks and the associated fork carrying linkage during transport as disclosed in our British Patent No. 2259292. Regulations limit the overhang of the forklift truck, that is the distance by which the forklift projects rearwardly of the vehicle chassis. This overhang restriction limits the size of the forklift truck that can be carried which in turn presents problems for the stability of the forklift truck during operation of the forklift truck.

A further problem with such forklift trucks is that when a truck is unloaded and it is desired to carry the forklift truck in piggy back fashion on the carrier vehicle, the weight of the forklift truck can cause instability and thus in many instances, the operators place the forklift trucks in the carrier itself in front of the rearmost wheels, or when it is a flat bed truck, on the bed of the truck. Such is not entirely satisfactory. There is obviously a need to carry the piggy back forklift truck in what is the more conventional piggy back fashion when the truck is fully loaded. - 2 The present invention is directed towards an improved mounting system which addresses the problems.

According to the invention there is provided a mounting system for mounting a forklift truck on a carrier vehicle chassis, the mounting system comprising a receiver shoe and a complementary carrier head which is releasibly lockably engagable with the receiver shoe by means of a quick-release mechanism, the receiver shoe for mounting on the chassis of the vehicle and the carrier head for mounting on the forklift truck and being operable to carry a load handling attachment on the forklift truck. As the forklift truck is positively engageable with the receiver shoe to which it can be locked this provides the possibility of enabling the forklift to lift itself onto the bed of the carrier vehicle for reducing or eliminating the overhang. This in turn presents the possibility of increasing the wheel base of the forklift truck to improve the stability of the forklift truck during use of the forklift truck.

To facilitate lifting the forklift onto the load-carrying bed of the vehicle, the receiver shoe may be mounted on top of the bed.

In some cases it may be desirable to have the receiver shoe slidably mounted on the bed. This enables the forklift truck to be positioned as desired on the bed for optimum weight distribution on the load carrying bed particularly when no load is being carried on the vehicle.

It is envisaged that the receiver shoe may be pivotally mounted on the bed for pivoting beneath the bed so that the bed can be free to carry loads without obstruction from the receiver shoe. _ 3 The receiver shoe may be mounted at a rear end of the chassis or alternatively the receiver shoe may be mounted in-board of the rear end of the chassis.

In another embodiment an engagement slot is provided in a load carrying bed of the vehicle, the receiver shoe being mounted within the slot. This advantageously allows the overhang of the forklift truck to be reduced by facilitating mounting the forklift truck in a more forward position at a rear end of the chassis. For example if the carrier head is mounted on a boom on the forklift truck then an outer free end of the boom can be inserted into the slot for engagement with the receiver shoe.

In a preferred embodiment the quick-release mechanism comprises complementary releasibly interengageable formations on the receiver shoe and the carrier head with locking means for releasibly interlocking the carrier head and the receiver shoe.

Preferably the interengageable formations comprise a pair of spaced-apart locking pins mounted on one of the carrier head and the receiver shoe and a complementary pair of catches mounted on the other of the carrier head and the lifting shoe.

In another embodiment the catches comprise a hook for reception of a locking pin and an associated lug spacedapart from the hook one of the locking pins being pivotally engageable with the hook for sliding engagement of the other locking pin with the lug to engage the locking pins between the hook and lug.

Preferably the locking means comprises a locking bolt mounted on the carrier head and movable between a retracted released position and an extended locking - 4 ~ position for retaining the locking pins in engagement with the lugs .

In one embodiment of the invention, the locking means comprises a hook for engagement over a limited pivotal movement on a bearing surface; an associated male member for reception with a female member; and a locking means for securing the male member within the female member.

Ideally the female member includes a bearing member for reception of the male member in sliding reduced friction engagement. Preferably the female member is formed from a slot. The bearing surface is formed from a substantially horizontally arranged rotatable pin.

Ideally, the male member is a bar having a receiver hole for reception of a locking bolt.

Detailed Description of the Invention The invention will be more clearly understood from the following description of some embodiments thereof, given by way of example only, with reference to the accompanying drawings, in which:Fig. 1 is a perspective view of a mounting system according to the invention; Fig. 2 is an elevational view of the mounting system in use for mounting a forklift truck on a carrier vehicle; Fig. 3 is a plan view of a rear end of a carrier incorporated portion of the mounting system.

Fig. 4 is a view similar to Fig. 2 showing another arrangement of the mounting system; Fig. 5 is a view similar to Fig. 2 showing another mounting system according to the invention; Referring to the drawings and initially to Figs. 1 to 3 thereof, there is illustrated a mounting system according to the invention indicated generally by the reference numeral 1. The mounting system 1 is for mounting a forklift truck 2 on a carrier vehicle chassis 3. A rear end of the vehicle chassis 3 is shown in Fig. 2. The mounting system 1 comprises a receiver shoe 4 for mounting on the chassis 3 and a complementary carrier head 5 which is releasibly engagable with the receiver shoe 4 by means of a quick-release mechanism. The carrier head 5 is mounted in use on the forklift truck 2 and the receiver shoe 4 is provided on the chassis.

The receiver shoe 4 has a frame with a pair of spacedapart side members 10 interconnected by cross members 11. Each side member 10 has a hook 12 at an upper end of the side member 10 and a lug 13 at a lower end of the side member 10. A through-hole 14 is provided in the lug 13.

The carrier head 5 has end struts 16 interconnected by cross bars 17. Locking pins 18, 19 are provided at an upper end and at a lower end respectively of each end strut 16. The upper locking pins 18 are engagable with the hooks 12 and the lower locking pins 19 are engagable with the lugs 14. Upon engaging the upper locking pins with the hooks 12 the carrier head swivels to engage the lower locking pins 19 with the lugs 13. A locking bolt 20 (Fig. 2) is movable by means of a ram 21 between a retracted disengaged position and an extended locking - 6 position (as shown in Fig. 2) for engaging through the hole 14 in each lug 13 to releasibly lock the carrier head 5 on the receiver shoe 4. Thus, conveniently the carrier head 5 can be quickly engaged and released from the receiver shoe 4. It will be noted that a load handling attachment may be releasibly engaged with the carrier head for carrying loads on the forklift truck 2.

The mounting system in this case further comprises wheel support plates 25 mounted on the chassis 3 which are engagable by front wheels of the forklift truck 2 to support the forklift truck 2 in the loaded position on the chassis 3 as shown in Fig. 2.

The forklift truck 2 illustrated in Fig. 2 has a chassis 26 mounted on wheels, comprising front wheels 27 and a rear wheel 28. A telescopic boom 29 is pivotally mounted on the chassis 10 for swinging movement in a substantially vertical plane for raising and lowering a load handling attachment mounted on the carrier head at a free end of the boom 29.

As can be seen in Fig. 3 the receiver shoe 4 is mounted within an engagement slot 30 recessed into a rear end of a load carrying bed 31 on the chassis. In this case the receiver shoe 4 is mounted in an inclined position as shown in Fig. 2. For engagement of the carrier head 5 with the receiver shoe 4 the boom 29 of the forklift 2 reaches into the slot 30. When the forklift truck 2 is mounted on the chassis 3 as shown in Fig. 2 a front end of the boom 29 which projects forwardly of a main body 35 of the forklift truck 2 is engaged within the slot 30 thus reducing the overhang of the forklift truck 2.

In use, for mounting the forklift truck 2 on the chassis 3 the carrier head 5 is engaged with the receiver shoe 4 _ 7 and locked in position by means of the locking bolts 20. Then the boom on which the carrier head 5 is mounted can be manipulated to raise the forklift truck 2 clear of the ground and locate the front wheels 27 of the forklift truck 2 on the carrier plates 25.· Straps and ties (not shown) can then be engaged between the forklift truck 2 and the rear end of the chassis 2 to firmly retain the forklift truck 2 on the chassis 3. After securing the forklift truck 2 the boom 29 of the forklift truck 2 may again be operated to release the load on the receiver shoe 4 so that the weight of the forklift truck 2 is carried on the mounting plates 25.

Referring now to Fig. 4 parts similar to those described previously are assigned the same reference numerals. In this case the receiver shoe 4 is shown mounted in an upright position on the chassis 3. In all other respects, the mounting system is similar to that described in Figs. 1 and 2.

Referring now to Fig. 5 there is illustrated another mounting system indicated generally by the reference numeral 40. Parts similar to those described previously are assigned the same reference numerals. In this case a receiver shoe 41 is provided having end plates 42 which are adapted for mounting directly on top of the load carrying bed 31 of the vehicle.

Although not illustrated the receiver 41 may be slidably mounted on the bed 31 of the vehicle for movement in the direction of arrow A. For example the end plates 42 may be slidably received in recessed tracks or channels in the bed 31. The provision of the receiver shoe 41 on top of the bed 31 allows the forklift truck to lift itself onto the bed 31 for carriage on top of the bed 31 if desired. Where provided, a sliding receiver shoe 41 allows ~ positioning of the forklift truck 2 at any desired location along the bed for example to facilitate weight distribution on the bed particularly when not carrying any load.

It is envisaged additionally that as well as mounting the end plates 42 in recesses, channels or tracks in the bed 31, that the receiver 41 may be pivotally mounted so as to hinge downwards towards the front of the truck into and beneath the truck bed when not required. This obviates the necessity for carrying the receiver 40 on the truck bed 31 at all times and clears it totally to receive a load. It is also envisaged that where the vehicle chassis is correctly formed that it may itself form the tracts or channels for the end plates 42.

It will be appreciated that the mounting system according to the invention provides for the positive locking engagement of a forklift truck on the chassis for lifting the forklift onto and off the chassis of the vehicle. Further, the positive locking engagement enables the forklift truck to be operated to lift itself onto the bed of the carrier vehicle if desired which conveniently will reduce or eliminate the overhang of the forklift during carriage of the forklift on the vehicle chassis.

The invention is not limited to the embodiments hereinbefore described which may be varied in both construction and detail.

Claims (5)

1. A mounting system for mounting a forklift truck on a carrier vehicle chassis, the mounting system comprising a receiver shoe and a complementary 5 carrier head which is releasably lockably engagable with the receiver shoe by means of a quick-release mechanism, the receiver shoe for mounting on the chassis of the vehicle and the carrier head for mounting on the forklift truck and being operable to 10 carry a load handling attachment on the forklift truck.

2. A mounting system as claimed in claim 1 wherein the quick-release mechanism comprises complementary releasably interengageable formations on the receiver 15 shoe and the carrier head with locking means for releasably interlocking the carrier head and the receiver shoe.

3. A mounting system as claimed in claim 2 wherein the interengageable formations comprise a pair of spaced20 apart locking pins mounted on one of the carrier head and the receiver shoe and a complementary pair of catches mounted on the other of the carrier head and the lifting shoe, and preferably the catches comprise a hook for reception of a locking pin and an 25 associated lug spaced-apart from the hook, one of the locking pins being pivotally engageable with the hook for sliding engagement of the other locking pin with the lug to engage the locking pins between the hook and lug.

4. A mounting system as claimed in claim 2 or 3 wherein the locking means comprises a hook for engagement over a limited pivotal movement on a bearing surface, an associated male member for reception with a female member, and a locking means for securing the male member within the female member, and preferably the female member includes a bearing member for reception 5. Of the male member in sliding reduced friction engagement.

5. A mounting system for mounting a forklift truck on a carrier vehicle chassis substantially as hereinbefore described with reference to the accompanying 10 drawings.