GB2317866A

GB2317866A - An overhead rail trolley

Info

Publication number: GB2317866A
Application number: GB9620681A
Authority: GB
Inventors: James Christopher Thorpe; Stephen George Miles
Original assignee: Polymark International Ltd
Current assignee: Polymark International Ltd
Priority date: 1996-10-04
Filing date: 1996-10-04
Publication date: 1998-04-08
Also published as: GB9620681D0

Abstract

A trolley (21) for conveying loads along an overhead rail (11) and which comprises a body (22) with rollers (26) mounted thereon for movement along the rail and a load suspension means (29,36) which is capable of movement about three axes relative to the body (21). The suspension means comprises a shackle (29) secured to the body by a pivot pin (33), and a hook (36) attached to the shackle by a ball and socket joint (41,42).

Description

An Overhead Rail Trolley Field This invention relates to trolleys for overhead rail systems for materials handling, and especially for use in commercial laundries.

Background In commercial laundries, dirty laundry and clean laundry are generally moved about the premises in collapsible bags which are supported at their upper ends by a rigid ring.

These rings in turn are generally moved around supported from overhead conveyor rails to facilitate movement around the site. The rails provide a track for the movement of trolleys from which the rings are suspended. The rail systems are generally inclined to the horizontal in order to use gravity to assist in the transfer of bags around the laundry.

When the loaded laundry bags are suddenly halted, or pass around bends or curves in the rail system, the momentum associated with the bag exerts a load on the trolley which may damage the trolley or the rail surfaces.

Statements of Invention Accordingly there is provided a trolley for conveying loads along an overhead rail system and which comprises a body with rollers mounted thereon for movement along the rail and a suspension means whereby loads are attached to the trolley wherein the suspension means is capable of movement about three axes relative to the body.

Preferably, the suspension means comprises a shackle pivotally secured to the body by a pin extending transversely of the rail in use, and a hook attached to the shackle by a ball and socket joint.

Preferably, the body is moulded from an engineering plastics material e.g. a glass filled polyamide and is substantially 'Y' shaped having a pair of diverging arms each with at least one roller mounted at the upper end portion thereof, and the loads are suspended from the leg.

The planes of rotation of the rollers on the two arms converge towards the load with a mutual angle therebetween in the range of 40-70 degrees of arc, preferably about 50 degrees.

Another aspect of the invention provides a trolley for conveying loads along an overhead rail system and which comprises a body with rollers mounted thereon for movement along the rail and a suspension means whereby loads are attached to the trolley wherein the suspension means includes a shackle pivotally secured to the body by a pin extending transversely of the rail in use, the pin being mounted in the body and projecting beyond each side thereof so that in use the end portions of the pin act as abutments for preventing movement of the trolley along the rail.

Yet another aspect of the invention provides a trolley for conveying loads along an overhead rail system and which comprises a body with rollers mounted thereon for movement along the rail and a suspension means whereby loads are attached to the trolley wherein the body is substantially 'Y' shaped having a pair of diverging arms each with at least one roller mounted at the upper end portion thereof, and any loads are suspended from the leg, the rotational planes of the rollers on the two arms converging towards the load with a mutual angle therebetween of between 40 -70 degrees of arc.

Description of Drawinqs The invention will be described by way of example and with reference to the accompanying drawings in which: Fig. 1 is a part sectional view of an overhead rail and trolley according to the invention, and Fig. 2 is a section through the trolley taken on the line 11-11 in Fig 1.

Detailed description of Example With reference to Figs. 1 & 2 of the drawings there is shown a section of overhead rail 11 having a central web 12 with a lower track portion 13 symmetrically arranged at its lower end. The track portion 13 has an upper arcuate surface 14 extending on each side of the web 12 along which a trolley 21 can move. In use the rail 11 forms part of an overhead conveyor system for the movement of laundry bags around a commercial laundry.

The trolley 21 comprises a body 22 which is cast or moulded from a suitable material which could be a metal but is preferably an engineering plastic such as glass-filled nylon. The body 22 is basically 'Y' shaped having two diverging arms 23,24 and a vertical leg 25. Each arm 23 and 24 has a roller 26 mounted at its upper end portion on its inner side adjacent the rail 11. The rollers 26 are mounted for rotation in bearings 27, preferably roller or ball bearings, which are recessed into the outer side of each arm 23 and 24 and held in place by a retainer plate 28.

The trolley 21 is arranged so that a roller 26 is located on each side of the web 12 with the rollers moving along the arcuate surface 14. The planes of rotation of the two rollers 26 are inclined to the vertical in use and converge towards the leg 22 with a mutual angle A therebetween of between 40-70 degrees and preferably about 50 degrees as shown in the drawings. The angle of 50 degrees is a compromise between the best planes of rotation for load bearing purposes and the best plane of rotation for stability on the curved surface 14 along which the trolley moves.

A 'U' shaped steel shackle 29 is secured to the leg 25 of the body 21 with the two arms 31,32 of the shackle pivotally connected to the leg 22 by a pin 33. The pin 33 is a stainless steel pin which extends transversely to the rail 11 and has end portions 34,35 that project beyond the sides of the leg 22. In use the end portions 34,35 act as abutments for preventing movement of the trolley 21 along the rail. Stops (not shown) located on each side of the rail engage the end portion 34,35 to halt the trolley and hence any loads being carried by the trolley.

A load carrying hook 36 is secured beneath the shackle 29 to its base 37 for carrying loads, for example laundry bags. The hook 36 is connected to the base 37 of the shackle by a ball and socket joint 39. The shank 40 of the hook passes through a clearance hole 43 in the base 37 and has an end portion with a part-ball 41 thereon the convex spherical surface of which is directed downwards. The ball 41 engages in a concave part spherical socket 42 in the upper surface of the base 37 of the shackle 29. The ball and socket joint allows the hook 36 to freely rotate about the vertical axis with limited relative rotation between the hook and shackle in the two horizontal axes (the movement being limited by the edges of the clearance hole 43).

The shackle 29 can also pivot about the horizontal axis transverse to the rail on the pin 33. Any loads carried by the hook 36 are therefore free to move in three axes so that relative movement between the bag and trolley can be accommodated without damage to a trolley. In general each laundry bag ring will be suspended from two trolleys located on diametrically opposite sides of the ring and spaced along the rail.

Claims

1. A trolley for conveying loads along an overhead rail system and which comprises a body with rollers mounted thereon for movement along the rail and a suspension means whereby loads are attached to the trolley wherein the suspension means is capable of movement about three axes relative to the body.

2. A trolley as claimed in Claim 1, wherein the suspension means comprises a shackle pivotally secured to the body by a pin extending in use transversely of the rail, and a hook attached to the shackle by a ball and socket joint.

3. A trolley as claimed in Claim 2, wherein the hook is free to rotate relative to the shackle around the vertical axis, and is capable of limited rotational movement only relative to the shackle about the two horizontal axes.

4. A trolley as claimed in Claim 2 or Claim 3 wherein the pin is mounted in the body and projects beyond each side thereof so that in use the end portions of the pin act as abutments for stopping the trolley.

5. A trolley as claimed in any one of Claims 1 to 4 wherein the body is substantially 'Y' shaped having a pair of diverging arms each with at least one roller mounted at the upper end portion thereof and the loads are suspended from the leg.

6. A trolley as claimed in Claim 5 wherein each roller is mounted on the inner side of a respective arm in bearings housed in within said arm.

7. A trolley as claimed in Claim 5 or Claim 6 wherein the rollers are arranged so that the rotational planes of the rollers on the two limbs are inclined to converge towards the load and the mutual angle between said planes is 40-70 degrees of arc, preferably 50 degrees.

8. A trolley as claimed in any one of Claims 1 to 7 wherein the body is moulded from glass-filled polyamide.

9. A trolley for conveying loads along an overhead rail system and which comprises a body with rollers mounted thereon for movement along the rail and a suspension means whereby loads are attached to the trolley wherein the suspension means includes a shackle pivotally secured to the body by a pin extending in use transversely of the rail, the pin being mounted in the body and projecting beyond each side thereof so that in use the end portions of the pin act as abutments for preventing movement of the trolley along the rail.

10. A trolley for conveying loads along an overhead rail system and which comprises a body with rollers mounted thereon for movement along the rail and a suspension means whereby loads are attached to the trolley wherein the body is substantially 'Y' shaped having a pair of diverging arms each with at least one roller mounted at the upper end portion thereof, and any loads are suspended from the leg, the rotational planes of the rollers on the two arms being inclined towards each other in the direction of the load with a mutual angle therebetween of between 40 -70 degrees of arc.

11. A trolley for conveying loads along an overhead rail system and which comprises a body with rollers mounted thereon for movement along the rail and a suspension means whereby loads are attached to the trolley, wherein the body is moulded from glass filled polyamide.