GB2186248A

GB2186248A - Overhead chain conveyor

Info

Publication number: GB2186248A
Application number: GB08603260A
Authority: GB
Inventors: G H Williams; W J Howgego
Original assignee: HANDLING CONSULTANTS Ltd
Current assignee: HANDLING CONSULTANTS Ltd
Priority date: 1986-02-11
Filing date: 1986-02-11
Publication date: 1987-08-12
Also published as: GB8603260D0; GB2186248B

Abstract

An overhead chain conveyor comprises a driven chain (1), a track (2) with load bearing capacity and hangers (3) which cooperate with load carriers (4) to which loads to be conveyed are attached. Where required, there is a lower track (5) which can support the load carriers. The load carriers may incorporate features (13, 15) which facilitate accumulation of loads on the lower track. When a hanger (3) and load carrier (4) approach a lower section of track (5), the chain track falls and causes the hanger and load carrier to disengage, thus transferring the load to the lower track, the conveyor functioning in these circumstances as a power and free conveyor. Hangers re-engage load carriers where the chain track rises to its original level. This system allows loads to be controlled independently of the driven chain, thus easing loading and unloading and providing holding and storage positions. <IMAGE>

Description

SPECIFICATION Overhead chain conveyor This invention relates to an overhead chain conveyor. Overhead chain conveyors are used widely for materials handling. They commonly comprise conveyor chain guided in a track, means to drive and tension said chain and features which enable loads to be attached and conveyed. The chain may incorporate hangers from which loads can be suspended. In such a manner loads can be conveyed continuously and are spaced according to the position of the hangers. In another arrangement there is a second track which runs parallel to the chain track. There are so called load trolleys which run freely on this second track. In this arrangement loads are attached to the trolleys and features on the chain engage with the trolleys to provide the conveying force.

The chain track is known as the power track and the trolley track the free track. Such "power and free" conveyers allow loads to be conveyed or not as required and may also incorporate features which allow loads to be accumulated on the free track. Furthermore, it is common to incorporate branch lines and loops into the conveyor system. Such a system is more versatile than a single track system but has the disadvantage of being expensive. There is scope for an overhead conveyor system which is essentially a monorail conveyor, which may have branches but also has facilities which allow loads to be accumulated, diverted or otherwise controlled independently of the power track.

According to the present invention there is provided an overhead chain conveyor comprising chain; means to drive said chain; means to tension said chain; track suitable for guiding and supporting said chain, said track also being able to withstand forces transmitted to it by loads which may be conveyed by said chain; one or more separate lengths of load supporting track, positioned in places, substantially parallel and adjacent to the first track; pendant features attached to said chain; load carriers which may at times, engage by means with the said pendant features or be supported by further means on the separate track, said load carriers incorporating features which effect engagement and disengagement with the pendant features and provide means for attaching loads.

The load carriers may be single or multiple units and co-operate with an equivalent number of pendant features.

Means may be provided which allow load carriers to accumulate on the separate track.

The conveyor may be configured as one or more continuous loops with the separate tracks being positioned at convenient places, thus providing loading, unloading, holding and storage positions.

The load carriers and the loads may be accumulated at these positions, thus easing loading and unloading operations and providing buffer and storage positions.

The separate sections of track can also act as transfer tracks which, in co-operation with suitable equipment, allow load carriers to pass from one conveyor loop to another.

The separate sections of track are only positioned where required so the conveyor is, for the most part, a monorail system.

The present invention will now be described, by way of an example, with reference to the accompanying drawings in which Figs.

1 to 7 inclusive and Fig. 2a depict parts of a chain conveyor according to the present invention. In the drawings, identical or like items are given the same reference numerals on the different figures.

Referring first to Fig. 1, part of an overhead chain conveyor is shown comprising a chain 1, a chain track 2, one of a number of hangers 3, one of a number of load carriers 4 and a lower track 5. Chain 1 and chain track 2 form a continuous loop of conveyor. Lower track 5 runs below chain track 2 over a limited length. The chain 1 incorporates brackets 6 and 7; brackets 6 being rigidly connected to the chain, whilst brackets 7 are connected to the chain in such a way that they can rotate in a vertical plane. The chain track 2 may be of slotted hollow section but other standard forms of track, to suit the particular chain which may be used, would be possible. Each hanger 3 comprises a plate member with plate features 8a, 8b, 9a and 9b attached perpendicular to the plate member.The hanger 3 is attached at each end to brackets 6 and 7 by joints 10 which allow a degree of rotation in the vertical and horizontal planes. Each carrier 4 comprises a slotted hollow section body 11; runners 12; proximity arm 13, said proximity arm being pivotally mounted between side plates 14; said side plates being rigidly attached to carrier body 11; trailing roller 15, said trailing roller being rotatably mounted between trailing roller brackets 16; and a hook 17, or similar, securely attached between side plates 14. Lower track 5 is of twin channels (only one shown), comprising rollers 18 (only one of two rows shown) and support brackets 19. Alternative supports for the lower track may also be provided.

Referring now to Figs. 2, 2a and 3 to 7, loads are normally conveyed by being suspended from a load carrier as depicted in Fig.

2. Load carrier 4 is suspended from hanger 3, the upper, slotted wall of the load carrier body 11 co-operating with plate features 9a and 9b on hanger 3 to support the load. Features 8a and 8b on hanger 3 restrain the load carrier longitudinally. Fig. 2a is cross-sectioned view of the chain, hanger and load carrier assembly shown in Fig. 2.

Referring to Fig. 3, when the hanger 3 and carrier 4 approach lower track 5, the runners 12 of load carrier 4 come into contact with rollers 18 and the load forces are thereby transferred from the chain track 2 to the lower track 5. As the forces are transferred, the chain track 2 falls to approach nearer the lower track. The hanger 3 is thus lowered relative to the load carrier 4. The forward propelling force is initially imparted by rear plate feature 8a bearing against the load carrier body 11. As the hanger 3 lowers, rear plate feature 9a comes into engagement with proximity arm 13 to provide the forward propelling force.

Referring now to Fig. 4, in the mode depicted, the load is supported by the track 5 and the propelling force is provided by the engagement of feature 9a with proximity arm 13.

Referring to Fig. 5, if a load carrier 4 is held in a stationary position on the track 5 and another carrier 4' approaches, the proximity arm 13 of the approaching carrier will come into engagement with the trailing roller 15 of the stationary carrier. As the proximity arm is brought out of engagement with feature 9a on hanger 3. The hanger 3 can pass freely through the bodies 11 and 11' of load carriers 4 and 4', thus leaving them accumulated on the lower track 5.

Referring to Fig. 6, a load carrier 4 is controlled by stop 20. Stop 20 may, for example, be a pneumatically operated bolt although other arrangements would be possible. Proximity arm 13 rides up on stop 20, causing disengagement of the forward propelling force and leaving the load carrier held on lower track 5. Other load carriers can then accumulate as previously described. If the stop 20 is withdrawn, proximity arm 13 swings down into position 13' and feature 9a on the next hanger 3 engages with it, thus driving the load carrier 4 forward. Following load carriers are similarly advanced and controlled by the stop.

Referring to Fig. 7, as the load carrier 4 is conveyed downstream of the stop 20, the chain track 2 rises away from the lower track 5. Plate feature 8a comes into engagement with carrier body 11 and plate feature 9a comes out of engagement with proximity arm 13. Forward driving means is thus transferred back to plate feature 8a, bearing against load carrier body 11. Hanger 3 rises as the chain is guided by the track 2 until firstly loading plate feature 9b and then trailing plate feature 9a engage with the load carrier body 11 to provide support for the load. The load carrier and load can then be lifted away from track 5 and are conveyed in a similar manner to that depicted in Fig. 2.

Claims

1. An overhead chain conveyor comprising chain; means to drive said chain, means to tension said chain, track suitable for guiding and supporting said chain, said track also being able to withstand forces transmitted to it by loads which may be conveyed by said chain; one or more separate lengths of load supporting track, positioned in places substantially parallel and adjacent to the first track; pendant features attached to said chain; load carriers which may at times engage by means with said pendant features or be supported by further means on the separate track, said load carriers incorporating features which effect engagement and disengagement with the pendant features and provide means of attaching loads.

2. An overhead chain conveyor according to claim 1, wherein the load carriers are single units and co-operate with single pendant features.

3. An overhead chain conveyor according to claim 1 wherein the load carriers are multiple units and co-operate with an equivalent number of pendant features.

4. An overhead chain conveyor according to any preceding claim wherein the load carriers can accumulate on the separate track.

5. An overhead chain conveyor according to any preceding claim which is configured as one continuous loop.

6. An overhead chain conveyor according to any of claims 1 to 4 which is configured in more than one continuous loop.

7. An overhead chain conveyor according to claim 6 wherein the separate sections of track act as transfer tracks which, in co-operation with suitable equipment, allow load carriers to pass from one conveyor loop to another.

8. An overhead chain conveyor substantially as described herein with reference to Figs. 1 to 7 inclusive and Fig. 2a of the accompanying drawings.