GB2389838A - Lifting Implement - Google Patents

Abstract

A lifting implement (10), for lifting and positioning a single kerbstone, comprises a jaw (12), having first and second elongate arm elements (12, 14) pivotably interconnected on a pivot axis (P) and first and second grab plates (18, 20) which, in use, downwardly extend from the free-ends (22) of the first and second elongate arm elements (12, 14), respectively, actuating means, preferably in the form of a hydraulic ram (26), by which the elongate arm elements (12, 14) can be pivoted relative to each other to open and close the jaw (12), and an attachment element (24) by which the lifting implement can be attached to a mechanical lifting arm.

Description

( LIFTING IMPLEMENT

This invention relates to a lifting implement and, in particular, to a lifting implement for lifting and positioning a single kerbstone.

It is well known that kerbstones are heavy. On site, these are often lifted by labourers and manually positioned. However, due to the weight, injuries often result, especially back injuries. The United Kingdom Health and Safety Executive has recently introduced guidelines on the weight that can be manually lifted by a labourer.

10 This has resulted in it becoming unacceptable practice for a kerbstone to be manually lifted without mechanical assistance.

The present invention seeks to provide a solution to this problem.

15 According to one aspect of the present invention, there is provided a lifting implement for lifting and positioning a single kerbstone, the lifting implement comprising a jaw having first and second elongate arm elements pivotably interconnected on a pivot axis and first and second grab plates which, in use, downwardly extend from the free-ends of the first and second elongate arm elements, 20 respectively, actuating means by which the elongate arm elements can be pivoted relative to each other to open and close the jaw, and an attachment element by which the lifting implement can be attached to a mechanical lifting arm.

Preferable and/or optional features of the present invention are set forth in

( 2 claims 2 to 11, inclusive.

The present invention will now be described, by way of example, with reference to the accompanying drawings, wherein: Figure I shows a side view of a lifting implement, in accordance with the present invention; and Figure 2 shows a front view of the lifting implement.

Referring to the drawings, a lifting implement 10 is shown therein and comprises a jaw 12 having first and second elongate arm elements 14 and 16 and first and second opposing grab plates 18 and 20 formed on the first and second elongate arm elements 14 and 16, respectively. The elongate arm elements 14 and 16 and grab IS plates 18 and 20 are arranged so that, in use, only a single kerbstone (not shown) can be received in the jaw 12 at any one time.

In this embodiment, two spaced first elongate arm elements 14 and two spaced second elongate arm elements 16 are provided. However, more or less than two first 20 and second elongate arm elements 14 and 16 could be used.

The first and second elongate arm elements 14 and 16 are rectilinear or substantially rectilinear, and are pivotably interconnected on pivot axis P. The first grab plate 18 interconnects the first elongate arm elements 14 and the second grab

( plate 20 interconnects the second elongate arm elements 16. Both grain plates 18 and 20 are attached at, or adjacent to, the free-ends 22 of the respective elongate arm elements 14 and 16, and project in a direction away from the pivot axis P. The grab plates 18 and 20 are planar or substantially planar, and each grab plate 18 and 20 5 extends at an angle a to the longitudinal axes A of the first and second elongate arm elements 14 and 16.

The lifting implement 10 also comprises actuating means by which the elongate arm elements 14 and 16 can be pivoted relative to each other, and an attachment 10 element 24 by which the lifting implement 10 can be attached to a mechanical lifting arm (not shown) of a suitable vehicle having a hydraulic system.

The actuating means is in the form of a single double-acting hydraulic ram 26 which can be connected, via suitable hydraulic fluid lines (not shown), to be in tiuid 15 communication with hydraulic fluid inputs / outputs of the suitable vehicle.

To hold the hydraulic ram 26, the lifting implement 10 is provided with independent secondary arm elements 28 and 30 which are formed on the grab plates 18 and 20 adjacent to the free-ends 22 of the first and second elongate arm elements 20 14 and 16. To maintain the balance of the lifting implement 10, the secondary arm elements 28 and 30 are symmetrically or substantially symmetrically positioned about an in use vertical plane Us (indicated in Figure 2) which bisects both grab plates 18 and 20. The first and second elongate arm elements 14 and 16 are also symmetrically or substantially symmetrically positioned about the said vertical plane Fit, but are offset

( 4 outwardly of the secondary arm elements 28 and 30.

The secondary arm elements 28 and 30 are L-shaped, or substantially L shaped, and are oriented so that the free-ends 32 of the secondary arm elements 28 5 and 30 project away from the free-edges 34 of the grabplates. The hydraulic ram 26 is held between the free-ends 32 of the secondary arm elements 28 and 30 at a suitable position so that the hydraulic ram 26 does not obstruct, or interfere with the operation of, the grab plates 18 and 20.

10 The attachment element 24 is pivotably interconnected with the elongate arm elements 14 and 16 on the pivot axis P. The attachment element 24 is also symmetrically or substantially symmetrically positioned about the said vertical plane B. 15 The attachment element 24 comprises a first part 36 and a second part 38 which is angularly displaceable relative to the first part 36. The first part 36 Is a U shaped or substantially U-shaped member and includes an elongate retaining pin element 40 which is received through axially aligned holes 42 at, or adjacent to, its free-ends 44.

The second part 38 of the attachment element 24 is an inverted U-shaped or substantially U-shaped member which is pivotably interconnected with the first and second elongate arm elements 14 and 16 on the pivot axis P at or adjacent to its free-

ends 46.

( 5 The bottom portion 48 of the first pan 36 of the attachment element 24 and the top portion SO of the second part 38 are fastened together with a fastening element 52, so that the said relative angular displacement can occur about an axis C which is perpendicular or substantially perpendicular to the pivot axis P. The first and second pans 36 and 38 are formed with stops (not shown) to prevent relative angular displacement of more than 360".

In use, the lifting implement 10 is releasably attached to the end of a 10 mechanically articulated lifting arm of a suitable vehicle, typically a digger, having a hydraulic system. Any other implement, such as a bucket (not shown), is first removed, and the end of the lifting arm is then releasably fastened to the U-shaped member (36) of the attachment element 24 by insertion and releasable locking of the retaining pin element 40. The hydraulic fluid lines are then connected to the hydraulic 15 fluid inputs / outputs of the digger.

When operated, the hydraulic ram 26 acts to open and close the jaw 12 formed by the elongate arm elements 14 and 16 and the grab plates 18 and 20. The angle a of the grab plates 18 and 20 to the longitudinal axes A of the elongate arm elements 14 20 and 16 is such that, when the grab plates 18 and 20 are closed on to opposing surfaces of a single kerbstone, the grab plates 18 and 20 become parallel or substantially parallel to each other. The grab plates 18 and 20 are also sufficiently dimensioned so that they extend over or substantially over the transverse extent or depth of the kerbstone. These two factors ensure that the kerbstone is lifted with as much of each

grab plate 18 and 20 as possible being in contact with as much of the transverse extent of the kerbstone as possible.

Once the kerbstone has been lifted, it can be easily manually oriented due to 5 the angularly displaceable attachment element. 'I'he kerbstone can then be positioned and laid.

The actuating means could take other forms, other than being a hydraulic ram.

For example, the actuating means could be a pneumatic device. In this case, the 10 suitable vehicle would have provision to accommodate such a pneumatic device.

lathe actuating means could also act directly on the first and second elongate arm elements or the grab plates, instead of requiring the secondary arm elements.

IS The lifting implement could also be used to lift and position other items, in addition, or alternatively, to kerbstones.

It is thus possible to provide a lifting implement that prevents at least one of the causes of on-site injury, and which can be quickly and easily attached and released 20 from a mechanical lifting arm. It is also possible to provide a lifting implement that, by use of grab plates that extend across or substantially across the entire transverse extent of a kerbstone, can more securely hold the kerbstone.

The embodiment described above is given by way of example only and various

( modifications will be apparent to persons skilled in the art without departing from the scope of the present invention as defined by the appended claims.

Claims (12)

1. A lifting implement for lifting and positioning a single kerbstone, the lifting implement comprising a jaw having first and second elongate arm elements pivotably 5 interconnected on a pivot axis and first and second grab plates which, in use, downwardly extend from the free-ends of the first and second elongate arm elements, respectively, actuating means by which the elongate arm elements can be pivoted relative to each other to open and close the jaw, and an attachment element by which the lifting implement can be attached to a mechanical lifting arm.

2. A lifting implement as claimed in claim 1, wherein the grab plates are arranged to enable only one kerbstone to be received therebetween.

3. A lifting implement as claimed in claim I or claim 2, wherein each grab plate 15 is planar or substantially planar.

4. A lifting implement as claimed in any one of the preceding claims, wherein each grab plate extends at an angle to the longitudinal axis of the respective elongate arm element so that, when the jaw is in an in use closed position, the grab plates are 20 parallel or substantially parallel to each other.

5. A lifting implement as claimed in any one of the preceding claims, wherein the grab plates in use extend over or substantially over the transverse extent of a kerbstone being lifted.

6. A lifting implement as claimed in any one of the preceding claims, further comprising secondary arm elements which are formed on the grab plates, adjacent to the free-ends of the elongate arm elements, the actuating means being attached between the secondary arm elements.

7. A lifting implement as claimed in any one of the preceding claims, wherein the actuating means is in the form of a hydraulic ram.

8. A lifting implement as claimed in any one of the preceding claims, wherein the 10 attachment element is pivotably interconnected with the elongate arm elements on the pivot axis.

9. A lifting implement as claimed in any one of the preceding claims, wherein the attachment element comprises a first part and a second part angularly displaceable 15 relative to the first part, the first part being attachable to the mechanical lifting arm and the second part being pivotably attached to the jaw.

10. A lifting implement as claimed in claim 9, wherein the axis about which the said angular displacement occurs is perpendicular or substantially perpendicular to the 20 pivot axis.

11. A lifting implement as claimed in any one of the preceding claims, wherein the lifting implement is a kerbstone lifting implement.

12. A lifting implement substantially as hereinbefore described with reference to the accompanying drawings.