GB2201393A

GB2201393A - Fork lift device for use with a crane

Info

Publication number: GB2201393A
Application number: GB08704248A
Authority: GB
Inventors: Terence Adrian Mallaghan
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-02-24
Filing date: 1987-02-24
Publication date: 1988-09-01
Also published as: GB8704248D0

Abstract

A fork lift device for use with a crane, comprises a frame (1) for suspension from a crane by means including a hydraulic rotator (6). A fork assembly (12) comprises two parallel upper elongate slide members (13) slidable in guide members (2) of the frame (1), a depending rectangular frame (4) and fork tines (15) underlying the members (13). The fork assembly (12) is movable by hydraulic means (16, 16') between the full and broken line positions to enable the tines to be engaged or disengaged with a load 8. A ballast weight (17) is arranged to move in opposition to the members (13) to maintain the device in a horizontal attitude. The movement of the weight may be rope and pulleys, the rope being connected to the members (13) and the weight, by chain and sprockets or by hydraulic motor. Transverse members (9) of the frame have rubber fenders (10) and a skirt (11) is provided on the frame to centre the load. <IMAGE>

Description

Fork lift device for use with a crane Description This invention relates to a fork lift device for use with a crane.

Such a device is known comprising an upright elongate member, an elongate cross member extending transversely to both sides from the bottom end of the upright member, two parallel fork tines extending to one side of the cross member transversely thereto and to the upright member, a single arm extending from the top end of the upright member over the fork tines and means on the arm to enable the suspension point of the device to be adjusted along the arm for balancing purposes. A disadvantage of such a device is the difficulty in moving the device into the required position to engage a load particularly with a crane mounted on a truck.

An object of the invention is to obviate or mitigate the above disadvantage.

According to the invention there is provided a fork lift device for use with a crane, comprising a frame, means on the frame to enable the frame to be suspended in a substantially horizontal attitude from a crane to overlie a load, a fork assembly comprising upper elongate slide means guided for linear movement in the frame between a fully retracted position and a fully extended position, means depending from an end of the slide means, which end is remote from the frame when the slide means are in the fully extended position, and fork tines parallel with each other and with the slide means and extending from the depending means in a direction to underlie the slide means so that when the slide means are in the fully retracted position the fork tines underlie the frame for engagement with a load and when the slide means are in the fully extended position the fork tines are clear of the space underlying the frame for disengagement from a load, and hydraulic means between the frame and the fork assembly for moving the fork assembly relative to the frame.

An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawing, in which: Fig. 1 is a side elevation of a device according to the invention; Fig. 2 is a plan of the device in Fig. 1; Fig. 3 is a section on line III-III in Fig. 1; and Fig. 4 is an end elevation of the device in Fig. 1.

In the drawing a fork lift device for use with a crane, comprises a frame 1 which is composed of two parallel elongate guide members 2 interconnected at one end of each member 2 by a cross member 3 carrying a fixed ballast 4. The device can be suspended from a crane (not shown) by means of a yoke 5 interconnecting the members 2 intermediate their ends. The yoke 5 is surmounted by a hydraulic rotator 6 which is itself surmounted by a lifting eye 7. The device shown is designed to carry a bale 8 of building bricks and transverse members 9 underlie the members 2 and are provided with rubber fenders. 10 to engage the top of the bale 8. In order to aid in locating the device properly in relation to the bale 8 a partial skirt 11 is provided on both sides of the pair of members 2 and at the right.

hand end in Figs. 1, 2 and 3.

A fork assembly 12 comprises two parallel upper elongate slide members 13 slidable in the members 2.

A rectangular frame 14 depends from the right hand ends (in Figs. 1, 2 and 3) of the members 13 and two fork tines 15, parallel with each other and with the members 2, extend from the frame 14 in a direction to underlie the members 2. A double-acting hydraulic ram has its cylinder 16 articulated to the cross member 3 and its piston rod 16' articulated to the top of the frame 14.

As shown in Fig. 3, a ballast 17 is slidable between the members 2 and is connected to a continuous wire rope 18 trained about pulleys 19. One of the members 15 is also connected at its free end to the wire rope 18.

In us, the fork assembly 12 is moved by the hydraulic ram 16, 16' to its position shown in broken line in Figs. 1, 2 and 3 where the members 2 are fully extended. The ballast 17 is thus automatically moved to the left hand end of the frame 1 in Figs. 1, 2 and 3 so that the empty device can hang with the frame 1 substantially horizontal. The device is then lowered onto the bale 8 and properly located with the aid of the partial skirt 11. The ram 16, 16' is operated so that the members 2 are fully retracted and the tines 15 are fully received in holes formed in the bale 8. The ballast 17 is automatically moved to the left hand end of the frame in Figs. 1, 2 and 3 so that when the weight of the bale 8 is taken by the tines 15, the device and the bale 8 hang horizontally. When unloading the bale 8, the bale 8 is set upon a supporting surface so that the weight is removed from the tines 15. The tines 15 are then extracted from the holes in the bale 8 by fully extending the members 2. Any slewing of the device which may be required is done by operating the rotator 6.

Instead of the wire rope 18 and pulleys 19 a chain and sprockets may be used. Alternatively the ballast 17 may be moved by a hydraulic motor.

The device is particularly intended for use with truck-mounted cranes. The device is also intended to handle any type of palletised load or any type of load which is normally handled by fork tines.

Claims

1. A fork lift device for use with a crane comprising a frame, means on the frame to enable the frame to be suspended in-a substantially horizontal attitude from a crane to overlie a load, a fork assembly comprising upper elongate slide means guided for linear movement in the frame between a fully retracted position and a fully extended position, means depending from an end of the slide means, which end is remote from the frame when the slide means are in the fully extended position, and fork tines parallel with each other and with the slide means and extending from the depending means in a direction to underlie the slide means so that when the slide means are in the fully retracted position the fork tines underlie the frame for engagement with a load and when the slide means are in the fully extended position the fork tines are clear of the space underlying the frame for disengagement from a load, and hydraulic means between the frame and the fork assembly for moving the fork assembly relative to the frame.

2. A fork lift device according to claim 1, comprising ballast means movable in the frame in opposition to the slide means for maintaining the frame in a substantially horizontal attitude when the slide means are in both the fully retracted and fully extended positions.

3. A fork lift device according to claim 1 or 2, wherein the suspension means includes a hydraulic rotator for slewing the device.

4. A fork lift device for use with a crane, substantially as hereinbefore described with reference to the accompanying drawing.