GB1576303A

GB1576303A - Fork lift trucks and to other apparatus having pronged load lifting devices

Info

Publication number: GB1576303A
Application number: GB3701677A
Authority: GB
Original assignee: LODLIFTA Ltd
Current assignee: LODLIFTA Ltd
Priority date: 1978-05-16
Filing date: 1978-05-16
Publication date: 1980-10-08

Description

(54) AN IMPROVEMENT IN OR RELATING TO FORK LIFT TRUCKS AND TO OTHER APPARATUS HAVING PRONGED LOAD LIFTING DEVICES (71) We, LODLIFTA LIMITED, a British Company, of New Orchard Road, Thurcroft, Rotherham, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following - statement: - The invention relates to fork lift trucks and to other apparatus having pronged load lifting devices and has for its object to provide an improvement therein. In particular, the object of the invention is to provide apparatus by means of which a hook can be suspended beneath the load lifting device.

According to the invention, there is provided apparatus for fitment to a pronged load lifting device'the apparatus including å central beam member which is to be disposed between a pair of prongs of the load lifting device; a transverse bearer member secured at a forward end of said beam inember for straddling said pair of prongs; means at the forward end of said beam member connecting or for connecting a load lifting hook thereto, or constituting a load lifting hook thereat; and a locking device pivotally connected at the rear end of the beam member for raising the rear end of the latter relative to the pair of prongs of the load lifting device when the apparatus is mounted on the lifting device, a part of the beam member or an element associated therewith being capable of being brought into locking engagement with a part of the load lifting device when the rear end ' of the beam member is raised relative to the pair of prongs. The transverse bearer member may be provided at its outer ends with depending lugs so that when the apparatus has been mounted on the lifting device the lugs lie against the outer edges of the pair of' prongs of the devicè. The locking device may include a locking lever provided with a pair of cam wheels rotatable on the opposite ends of a spindle carried by the locking lever.The locking lever may be pivotally connected to an upstanding plate part of the central beam member and the spindle on which the cam wheels are rotatable may extend through' an arcuate slot in said plate, the arrangement being such that when the locking lever is operated the cam wheels are caused to bear downwardly on rearward parts of the prongs of the lifting device causing a notched portion of the plate part of the central beam member to engage å !cro'ss member of the device.

In' order that the invention may be fully understood and readily carried into effect, the same will now be described, by way of example only, with reference to the drawings accompanying the Provisional Speci fiction, of which: - Fig. 1 is a perspective view of the front of a fork lift truck to which apparatus embodying the invention has been fitted, and Fig. 2 is a perspective view of the apparatus embodying the invention.

Referring now to the drawings, Fig. 1 is à view of the front part of a fork lift truck of conventional construction, that is to say having a pronged lifting device 10 mounted for vertical movement- on a vertical "mast" 12. The lifting device 10 includes a pair of prongs- 11- mounted -for lateral adjustment, that is to say adjustment towards and away from each other, on cross members 38 and 40 of a lifting-frame. The truck is shown provided with apparatus embodying the invention and generally indicated 14.

Referring now in particular to Fig. 2, the apparatus 14 is constituted by a central beam member 16 which-is slightly longer than the prongs of the lifting device 10.

At a forward end of the central beam a load lifting hook 13 is connected to a shackle 15. Towards the forward end-of said beam there is a transverse bearer member 18 welded to the beam so that it projects equally from opposite sides of the latter, and depending lugs 20 are welded to the outer ends' of the bearer member so that when the apparatus has been mounted on the lifting device 10 the lugs lie against the outer edges of the pair of prongs 11 of the device as shown in Fig. 1. At its rear end the central beam member is provided with an upstanding plate 22, the latter having a notch 24 and forwardly of the notch an aperture through which a pivot pin 25 extends.

The pivot pin 25 pivotally secures a locking lever 26 to the central beam member 16 and the locking lever includes spaced plates 28 with a cross handle 30 welded thereto near their outer ends. The locking lever also includes a pair of cam wheels 32 which are freely rotatable on the opposite ends of a spindle 34 extending through aligned holes in said spaced plates, said spindle being slidable along an arcuate slot 36 in the upstanding plate 22 as the locking lever is moved about the axis of the pivot pin.

The arrangement is such that when the pronged lifting platform of the fork lift truck is in its lower position as shown in Fig. 1, and the prongs have been brought close together on the lifting frame, the apparatus 14 can be mounted thereon, that is to say can be dragged rearwardly until the transverse bearer member straddles the prongs and the notched portion of the plate 22 is disposed beneath the lower cross member 38 of the lifting frame (the locking lever 26 being used in upstanding condition as a carrying handle during this operation). When the apparatus has been so positioned on the prongs, the locking lever can be pivoted downwardly so that the cam wheels are caused to bear downwardly on a rearward part of the respective prongs, as shown in Fig. 1.This causes the rear end of the central beam member to be raised relative to the prongsso that the notched portion of the -plate -22 is engaged by the lower cross member 38 beneath which it has been positioned. Consequently, until the locking lever has again been lifted, the apparatus is securely connected to the pronged lifting platform of the truck and the truck can be used as a light mobile crane for lifting and moving articles which cannot otherwise easily be lifted and moved, (for example an engine may be lowered into position in a vehicle by a fork lift truck which has been modified as described).

Various modifications may be made without departing from the scope of the invention. For example, it would be an advantage to provide a lifting handle on the transverse bearer member 18 to minimise any danger of a workman being injured by trapping his hand between the bearer member and one of the prongs of the lifting device. Alternatively, such a lifting handle could be pivotally connected to the central beam, conveniently by the pivot pin connecting the shackle to the beam. - -A further possible modification would be to increase the depth of the central beam, at least in the region of the transverse. bearer member, so that the latter can extend through an aperture formed in the beam in that region.The transverse bearer member would still be welded to the beam of course but the strength of the apparatus would not be wholly dependent on the strength of the weld.

WHAT WE CLAIM IS: - 1. Apparatus for fitment to a pronged load lifting device the apparatus including a central beam member which -is to be disposed between a pair of prongs of the load lifting device; a transverse bearer member secured at a forward end of said beam member for straddling said pair of prongs; means at the forward end of said beam member connecting or for connecting a load lifting hook thereto, or constituting a load lifting hook thereat; and a locking device pivotally connected at the rear end of the beam member for raising the rear end of the latter relative to the pair of prongs of the load lifting device when the apparatus is mounted on the lifting device, a part of the beam member or an element associated therewith being capable of being brought into locking engagement with a part of the load lifting device when the rear end of the - beam member is raised relative to the pair of prongs.

2. Apparatus according to claim 1, in which the transverse bearer member is provided at its outer ends with depending lugs so that when the apparatus has been mounted on the lifting- device the lugs lie against the outer edges of the pair of prongs of the device.

3. Apparatus according to either one of the preceding claims, in which the locking device includes a locking lever provided with a pair of cam wheels - rotatable on the opposite ends of a spindle carried by the locking lever.

4. Apparatus according to claim 3, in which the locking lever is pivotally connected to an upstanding plate part of the central beam member and the spindle on which the cam wheels are rotatable extends through an arcuate slot in said plate, the arrangement being such that when the

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. a load lifting hook 13 is connected to a shackle 15. Towards the forward end-of said beam there is a transverse bearer member 18 welded to the beam so that it projects equally from opposite sides of the latter, and depending lugs 20 are welded to the outer ends' of the bearer member so that when the apparatus has been mounted on the lifting device 10 the lugs lie against the outer edges of the pair of prongs 11 of the device as shown in Fig. 1. At its rear end the central beam member is provided with an upstanding plate 22, the latter having a notch 24 and forwardly of the notch an aperture through which a pivot pin 25 extends. The pivot pin 25 pivotally secures a locking lever 26 to the central beam member 16 and the locking lever includes spaced plates 28 with a cross handle 30 welded thereto near their outer ends. The locking lever also includes a pair of cam wheels 32 which are freely rotatable on the opposite ends of a spindle 34 extending through aligned holes in said spaced plates, said spindle being slidable along an arcuate slot 36 in the upstanding plate 22 as the locking lever is moved about the axis of the pivot pin. The arrangement is such that when the pronged lifting platform of the fork lift truck is in its lower position as shown in Fig. 1, and the prongs have been brought close together on the lifting frame, the apparatus 14 can be mounted thereon, that is to say can be dragged rearwardly until the transverse bearer member straddles the prongs and the notched portion of the plate 22 is disposed beneath the lower cross member 38 of the lifting frame (the locking lever 26 being used in upstanding condition as a carrying handle during this operation). When the apparatus has been so positioned on the prongs, the locking lever can be pivoted downwardly so that the cam wheels are caused to bear downwardly on a rearward part of the respective prongs, as shown in Fig. 1.This causes the rear end of the central beam member to be raised relative to the prongsso that the notched portion of the -plate -22 is engaged by the lower cross member 38 beneath which it has been positioned. Consequently, until the locking lever has again been lifted, the apparatus is securely connected to the pronged lifting platform of the truck and the truck can be used as a light mobile crane for lifting and moving articles which cannot otherwise easily be lifted and moved, (for example an engine may be lowered into position in a vehicle by a fork lift truck which has been modified as described). Various modifications may be made without departing from the scope of the invention. For example, it would be an advantage to provide a lifting handle on the transverse bearer member 18 to minimise any danger of a workman being injured by trapping his hand between the bearer member and one of the prongs of the lifting device. Alternatively, such a lifting handle could be pivotally connected to the central beam, conveniently by the pivot pin connecting the shackle to the beam. - -A further possible modification would be to increase the depth of the central beam, at least in the region of the transverse. bearer member, so that the latter can extend through an aperture formed in the beam in that region.The transverse bearer member would still be welded to the beam of course but the strength of the apparatus would not be wholly dependent on the strength of the weld. WHAT WE CLAIM IS: -

1. Apparatus for fitment to a pronged load lifting device the apparatus including a central beam member which -is to be disposed between a pair of prongs of the load lifting device; a transverse bearer member secured at a forward end of said beam member for straddling said pair of prongs; means at the forward end of said beam member connecting or for connecting a load lifting hook thereto, or constituting a load lifting hook thereat; and a locking device pivotally connected at the rear end of the beam member for raising the rear end of the latter relative to the pair of prongs of the load lifting device when the apparatus is mounted on the lifting device, a part of the beam member or an element associated therewith being capable of being brought into locking engagement with a part of the load lifting device when the rear end of the - beam member is raised relative to the pair of prongs.

locking lever is operated the cam wheels are caused to bear downwardly on rearward parts of the prongs of the lifting device causing a notched portion of the plate part of the central beam member to engage a cross member of the device.

5. Apparatus for fitment to a pronged load lifting device, the apparatus being constructed, arranged and adapted to operate substantially as hereinbefore described with reference to and as illustrated by the drawings accompanying the Provisional Specification.