GB2189218A

GB2189218A - Lifting appliance

Info

Publication number: GB2189218A
Application number: GB08609223A
Authority: GB
Inventors: John Prothero
Original assignee: LLOYDS BRITISH TESTING CO Ltd
Current assignee: LLOYDS BRITISH TESTING CO Ltd
Priority date: 1986-04-16
Filing date: 1986-04-16
Publication date: 1987-10-21
Also published as: GB8609223D0; GB2189218B

Abstract

A lifting appliance for a cylindrical load 29 has a pair of pivoted arms 1,3, with one set of ends connected together by toggle links 11,13 and the other set of ends carrying jaws 7,9 for engaging the periphery of the load. One jaw is constituted at its free end by a pivotally mounted pad 17 and the other jaw at its free end has a pad 23 which is displaceable to a limited extent along the arm and can be latched in position on the arm, thereby providing this jaw with two effective lengths which can be used when lifting loads of relatively large and small diameter. The latch is provided by a member 27 which is engageable with a projection 25. Two identical appliances may be provided side-by-side suspended from an elongate bar. <IMAGE>

Description

SPECIFICATION Lifting appliance This invention relates to lifting appliances which are capable of gripping the curved periphery of a cylindrical load.

When transporting cylindrical loads, such as reels of news print, it is desirable that the reels should be readily and safely lifted by a lifting appliance which grips part of the curved periphery of the reel and which does not cause damage to the surface of the reel.

A lifting appliance for a cylindrical load is known which consists of a pair of arms pivoted together with one pair of corresponding ends of the arms being pivotally connected together by toggle links and connected to a suspension member and the other pair of corresponding ends of the arms are shaped to bear against the curved periphery of the cylindrical load when the suspension member is raised.

With such a lifting appliance it is essential that the arms engage against the cylindrical load over at least 1800 of the periphery of the load and, preferably, the gripping arms should extend around the lifting appliance is designed to accommodate a load of a particular diameter and, although the arms which grip the cylindrical load are each curved so that in their gripping position they overlie and are close to the periphery of the load, when the load is of a smaller diameter than that for which the appliance is designed, it is found that only the end portions of the arms bear against the load and, consequently, this is dangerous and can cause damage to the surface of the load when the load is a reel of newsprint.

An object of the present invention is to provide a lifting appliance for cylindrical loads which is capable of accommodating loads of different diameters in a safe manner and without causing damage to the surface of the load.

According to the present invention a lifting appliance capable of gripping the curved periphery of a cylindrical load comprises a pair of arms pivoted together between their ends, one pair of corresponding ends being pivotally connected together by toggle links and connected to a suspension member and the other pair of corresponding ends carrying jaws for engaging the curved periphery of a cylindrical load, the jaw on one arm being constituted by a pad which is pivotally mounted on the arm and the jaw on the other arm being constituted by a pad which is displaceable to a limited extent in the direction of the length of the arm between a first position, in which the pad can be releasably locked to the arm, and a second position, where the pad extends the effective length of the arm as compared with the effective length when the pad is in the first position.

With such an appliance, the effective length of one of the arms can be increased thereby permitting the arms to extend around the periphery of a reel of greater diameter than is the case when the effective length of the arm is fixed. Thus reels of different diameters can be safely lifted by the appliance.

By arranging for one of the pads to be pivotally mounted on the arm, it enables that arm to be projected into the space above the abutting parts of a pair of reels arranged sideby-side in abutting relation with their longitudinal axes horizontal.

In order that the invention may be more readily understood, it will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows diagrammatically a lifting appliance in accordance with the present invention fitted to a reel of a maximum permitted diameter; and Figure 2 shows diagrammatically the lifting applicance gripping a reel of a permitted minimum diameter.

A lifting appliance comprises a pair of arms 1, 3 which are pivoted together by a pivot 5.

Between the pivot 5 and the outer upper end of each arm 1, 3 the arm is approximately straight whereas, between the pivot 5 and the lower end of each arm 1, 3, there is an arcuate portion 7, 9, respectively. The length of the portion 9 is greater than that of the portion 7. The outer upper ends of the arms 1, 3 are pivotally connected to ends of toggle links 11, 13, respectively, which are pivoted at their opposite ends to a suspension member 15. By raising and lowering the suspension member 15, the portions 7, 9 of the arms can move towards and away from each other.

On the outer end of the portion 7 of the arm there is a pad 1 7 which is pivotally secured to the portion 7 by a pivot pin 19. The inner surface 21 of the pad 17 is of arcuate form and the pad can be positioned so that the surface forms a continuation of the inside surface of the portion 7. The pad is prevented from pivoting outwards from the position shown in the figures.

At the outer end of the portion 9 of the arm 3 a pad 23 is located. This pad is free to move for a limited extent in the direction of the length of the portion 9 of the arm. In the position shown in Figure 1, the pad 23 is at its most outermost position relative to the portion 9 and the pad serves to increase the effective length of the portion 9. The inner surface of the pad 23 is of arcuate form to serve as a continuation of the curved inner surface of the portion 9. In the position shown in Figure 2, the pad 23 has been displaced relative to the portion 9 in the direction of its length in order to overlap the end of the portion 9 and thereby not to extend the effective length of the portion 9. A projection 25 is mounted on the portion 9 of the arm and a latch 27 is pivotally mounted on the pad 23.

When the pad 23 is displaced to its inmost position, as shown in Figure 2, the latch 27 can be latched over the projection 25 to retain the pad in the inmost position.

In use, in order to accommodate a maximum diameter reel 29, the pad 23 is lowered away from the projection 25 in order to maximise the effective length of the portion 9. In this way, the portions 7, 9 of the arms can fit round a cylindrical reel 29 of a maximum permitted diameter. When the suspension member 15 is raised, pads 17, 23 abut against and grip the curved periphery of the reel. In the arrangement shown in Figure 2, a minimum diameter reel 29a has to be gripped and, to this end, the pad 23 is moved to its position where it is latched on to the projection 25 and the minimum diameter reel can be gripped when the suspension member 15 is raised. In both arrangements the pads abut against the periphery of the reel at positions spaced by an angle considerably greater than 1800 and preferably in the order of 220".

When the suspension member is raised, the toggle links 11, 13 cause the upper ends of arms 1, 3 to pivot towards each other thereby causing the reel to be gripped by the pads 17, 23.

When a pairof reels are mounted in side-byside abutting relation with the longitudinal axes of the reels substantially horizontal, the pad 17 can move into the limited space above the abutting part of the adjacent reels when the appliance is lowered onto one of the reels. If the pad were not pivoted to the portion of the arm 1, the pad would not be able to penetrate into the space between the two reels.

In use, the appliance is lowered on to a flat horizontal surface while the arms 1, 3 are latched in an open position. The pad 23 abuts against the horizontal surface as the appliance is lowered causing the pad to be displaced relative to the portion 9 of the arm. If the operator wishes to raise a maximum diameter reel, no action is required and the pad is allowed to move away from the projection 25 when the appliance is again lifted from the surface, but, on the other hand, if the smaller diameter reel is to be lifted, the operator engages the latch 27 on to the projection 25 to hold the pad in the raised position before the appliance is lifted to take the pad away from the horizontal surface. In this way the pad is retained in its displaced position.

Conveniently the appliance shown in the figures is duplicated and is located side-byside from an elongate suspension member 15.

With this appliance the load is gripped by two separate sets of pads on separate arms operated by separate toggle links connected to the suspension member.

Claims

1. A lifting appliance capable of gripping the curved periphery of a cylindrical load comprising a pair of arms pivoted together between their ends, one pair of corresponding ends being pivotally connected together by toggle links and connected to a suspension member and the other pair of corresponding ends carrying jaws for engaging the curved periphery of a cylindrical load, the jaw on one arm being constituted by a pad which is pivotally mounted on the arm and the jaw on the other arm being constituted by a pad which is displaceable to a limited extent relative to the arm between a first position, in which the pad can be releasably locked to the arm, and a second position, where the pad extends the effective length of the arm as compared with the effective length when the pad is in the first position.

2. A lifting appliance as claimed in claim 1, in which the part of each arm between the pivot and the end carrying the jaw is of arcuate form.

3. A lifting appliance as claimed in claim 2, in which the surface of each pad which engages the load is of arcuate form and is of substantially the same curvature as that of the inside surface of the arm on which it is mounted.

4. A lifting appliance as claimed in claim 3, in which the pad which is pivotally mounted on the arm is permitted to pivot inwardly of the arm but is prevented from pivoting outwardly of the arm.

5. A lifting device substantially as hereinbefore described with reference to the accompanying drawings.

6. A lifting device comprising a pair of lifting appliances each as claimed in any preceding claim with the toggle links of the two appliances being connected to opposite ends of an elongate bar.