GB2281273A - Improvements relating to storage carousels - Google Patents

Abstract

A storage carousel has a plurality of trolleys (1) coupled to an endless drive mechanism with two parallel straight runs between semi-circular turns at each end. Each trolley (1) is coupled to a drive chain (4) by a direct pivot (6) and by a link (9) pivoted to the trolley (1) and to the chain (4) at points horizontally separated from the direct pivot (6). This enables the trolley (1) to follow a fully controlled path both along the straight and around the end turns. There can be two synchronised chains (4) one above the other, and they can give stability to the trolleys (1), which may each run on one wheel. Provision is made for supporting the chains (4) along the straight runs between sprocket wheels (10) at the end turns. <IMAGE>

Description

"Improvements relatina to Storaae Carousels" This invention relates to storage carousels. It concerns arrangements where a plurality of trolleys are coupled in a closed loop, and a selected one can be brought to a loading/unloading position by shifting the chain of trolleys around the loop.

A circular carousel is wasteful of space. If the loop is "squashed" into a long rectangle with rounded ends, many carousels can be packed closely together in a parallel array. Their proximity may be such that there will not be access between adjacent carousels to the long straight sides, but one or both ends could be accessible. Thus any required trolley would be brought around the loop to appear at the selected end, the other trolleys being shunted round with it.

However, there are certain problems with this arrangement. The trolleys have to travel in a straight line and then round a sharp curve. A set of fixed wheels would create drag at the loop ends, while castors are expensive, and reversing the movement of the loop would cause each trolley to try to sway out of line as the castors swivelled.

Then there is the coupling of the trolleys. If they were hinged directly together, there could be a problem with decoupling them. There may be occasion to take a damaged one out of service, for example, or to replace certain trolleys having one type of storage capacity with others having a different storage arrangement. It would therefore be better for each trolley to be coupled independently of the adjacent ones to the chain or other endless loop drive. But at the same time, this must not allow the trolleys to swing about uncontrollably. It must allow close packing along the straights, while not impeding motion around the curved ends.

Closed loop chains are the preferred drive means but they are heavy and tend to sag between sprocket wheels.

For the arrangement proposed, it should be kept straight and effectively rigid between sprocket wheels, and at the same time there should be no interference with the connection of the trolleys to it.

It is the aim of this invention to answer these problems at least in part.

According to one aspect of the present invention there is provided a storage carousel comprising a plurality of trolleys coupled at their rear sides to endless loop drive means, the loop being substantially horizontal and non circular, wherein each coupling comprises a direct pivot between first points on the trolley and on the drive means and, horizontally separated from the first points, a link pivoted at one end to a second point on the trolley and at the other end to a second point on the drive means.

This link swings as necessary to accommodate to different configurations of the chain or other drive means as it progresses along a straight and then around a curve.

The endless loop drive means will be traversed around guide wheels, and there will preferably be fixed guide tracks between the guide wheels for runners which support the drive means, each track having an open ended longitudinal slot for the connection to the trolleys to pass through.

These runners can effectively be part of the chain, and travel all around the loop, but of course they will be arranged not to interfere with the guide wheels when clear of the guide tracks.

The tracks may each comprise two spaced mirrorimage elements of substantially S and Z section, the elements being arranged to provide a relatively wide upper passage in whose wings can run rollers for supporting the drive means, and a relatively narrow lower passage which closely and laterally confines the drive means.

The or each loop of the drive means will preferably comprise an endless chain whose links are mutually pivoted about vertical axes. Some pivot pins between pairs of links may be vertically extended to provide the first and second points on the drive means, while others may be verticaly extended to couple to bogies which are the supporting runners. Each bogie may be two wheeled, the wheel axis being non-intersecting with the axis of the coupled pivot pin, so that the bogie trails castor fashion. At least some of the bogies may be extended to provide support at two adjacent pivot points on the chain.

According to another aspect of the present invention there is provided a storage carousel comprising a plurality of trolleys coupled at their rear sides to endless loop drive means, the trolleys running on an unstable wheel base and being kept upright by the drive means.

Each trolley may have a single wheel, or two wheels in tandem. They could run in a floor track.

The drive means will preferably have two endless loops, synchronised and vertically spaced to connect to points near the top and bottom of each trolley.

For a better understanding of the invention, one embodiment will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side elevation of a storage rack carousel, Figure 2 is a plan view of the carousel of Figure 1, Figure 3 is a diagrammatic detail, in plan, of part of the carousel, Figure 4 is a cross section of a track and chain forming part of the carousel, Figure 5 is a diagrammatic side elevation showing a detail of the chain and its support, Figure 6 is a diagrammatic plan view of the chain and its support, corresponding to Figure 5, Figure 7 is another cross-section of another part of the track and chain showing a coupling to a trolley, and Figure 8 shows alternative link pin support arrangements that may be used in the carousel.

Referring to Figures 1 and 2, a number of trolleys 1 are coupled in an elongate closed loop and can be shifted around the loop in either direction by a chain arrangement, to be described later, to present any selected trolley at one end and its opposite one at the other end. It will be understood that this can be one of many similar closed loops arranged in a closely parallel array, adjacent loops being indicated in outline in Figure 2. The trolleys 1 along the straights will be inaccessible, but those at the ends can be loaded or unloaded from alleyways 2.

Each trolley 1 is tall, fairly shallow and not very wide. They have fronts open to the outside of the loop, mesh sides and backs, and shelving. This may be tilted for safe retention of goods as shown at the left hand end of Figure 1. But these aspects of the trolleys are not of importance to the invention. Their significant features are that each is supported on a single central wheel 3, which may run in a floor track, and that at the rear they are coupled to upper and lower endless chains 4 and 5 by which they are held upright and by which they can be progressed around the loop. At each level the coupling is at two points as best seen in Figure 3. There is one extensively projecting lug 6 whose tip is coupled directly to the chain by one of a pair of pins 7 to be described later. Horizontally spaced from this there is another, shorter lug 8 and this is coupled to the other pin 7 by a link 9.

Instead of a single wheel, there could be two wheels in tandem, giving a bit more stability, with little increase in drag.

Figure 3 shows two trolleys 1, one on a straight run of the chain 4 and the other on the crown of the curved end of the loop where the chain is carried round and driven by a sprocket wheel 10. The sprocket wheels at each end are on a common vertical shaft so that the chains 4 and 5 are positively synchronised. When the chain is straight, there is maximum separation between the respective pins 7 which couple a common trolley. This is indicated by distance X.

But when the trolley is running around one of the curves, the chordal distance between the pins 7 decreases, and this is indicated by the dimension Y. The swinging link 9 accommodates to this as illustrated in Figure 3, but with just one such link and the lug 6 being fixed to the trolley, the latter cannot swing about freely. It will follow a predetermined path.

Referring to Figures 4 to 6, each chain 4 and 5 is of flat parallel link form joined by hollow pins, and resembles a large scale cycle chain. Although the chain can be tensioned by means acting on one or both sprocket wheel shafts at the ends of the loop, there is an inevitable tendency to sag. It is therefore supported at intervals by runners 11 within a track 12. In fact, there are two tracks 12 one along each straight; the sprocket wheels 10 afford support around the ends of the loop.

Each track comprises a squared S-section strip 13, and its mirror image, a squared Z-section strip 14. The upper portions of these strips provide two horizontal Ushaped channels 15, the U's being on their sides and open towards one another. Each runner 11 has a body 16 flanked by rollers 17, preferably of nylon, which run in these channels. The chain 4 (or 5) is carried below the body 16 by a stud 18 through the hollow pin joint of adjacent links and a nut 19 threaded on its lower end. The chain is closely confined between the lower vertical limbs of the strips 13 and 14.

Not every link joint will require such a supporting runner; the number provided will depend on the size and weight of the chain. But, as shown in Figures 5 and 6, one runner can co-operate with two such joints and thus increase its support. Projecting lengthwise of the chain from the body 16 there is an arm 20 with a downwardly extending finger 21 at its extremity which engages through the next hollow pin of the chain. The runner 11 is kept in the correct attitude by its stud 18 being constrained to the vertical by the hollow link pin through which it passes.

The arm 20 is therefore kept horizontal (although it can swing with any bend in the chain) and so the finger 21 will firmly support the chain one link away. This arrangement also prevents the runner slewing.

Figures 5 and 6 also show the trolley coupling pins 7. In practice these may well be spaced further from a chain support runner 11, but the illustrations have been condensed for convenience. Figure 7 shows a pin 7 in more detail. It projects upwardly and co-axially from a cylindrical body 22 which lies between the channels 15, being supported on the chain 4 (or 5) by the shoulder between the lower end of that body and a co-axial threaded stud 23 which passes down through a hollow link pin to be secured by a nut 24.

For attachment of a trolley, it is offered up slightly raised and is then lowered down for the lugs 6 to be entered by the pointed ends of vertically aligned pins 7 on the chains 4 and 5. The links 9 can then be dropped into place. The end that fits over a pin 7 is enlarged and has a bush 25, while the other end is coupled to a lug 8 by a nut and bolt 26. There is sufficient access, as can be seen in Figures 2 and 3, for this fitting operation. With the trolley coupled at all four points and resting on its single wheel 3, the pins 7 will keep it upright.

Figure 8(a) shows a heavier duty pin arrangement, where the body 22 is provided with an extension arm 27 and finger 28 similar to the arm 20 and finger 21. For really heavy duty, the pin arrangement of Figure 8(b) may be used, where the body 22 and threaded stud 23 are duplicated by body 29 and stud 30, and the two bodies are rigidly connected at the pitch length of one link by a bar 31.

Claims (15)

1. A storage carousel comprising a plurality of trolleys coupled at their rear sides to endless loop drive means, the loop being substantially horizontal and non circular, wherein each coupling comprises a direct pivot between first points on the trolley and on the drive means and, horizontally separated from the first points, a link pivoted at one end to a second point on the trolley and at the other end to a second point on the drive means.

2. A storage carousel as claimed in Claim 1, wherein the endless loop drive means are traversed around guide wheels, there being fixed guide tracks between the guide wheels for runners which support the drive means, each track having an open ended longitudinal slot for the connection to the trolleys to pass through.

3. A storage carousel as claimed in Claim 2, wherein each track comprises two spaced mirror-image elements of substantially S and Z section, the elements being arranged to provide a relatively wide upper passage in whose wings can run rollers for supporting the drive means, and a relatively narrow lower passage which closely and laterally confines the drive means.

4. A storage carousel as claimed in Claim 1, 2 or 3, wherein the or each loop of the drive means comprises an endless chain whose links are mutually pivoted about vertical axes.

5. A storage carousel as claimed in Claim 4, wherein pivot pins between pairs of links are vertically extended to provide the first and second points on the drive means.

6. A storage carousel as claimed in Claim 4 or 5, wherein pivot pins between pairs of links are vertically extended to couple to bogies which are the supporting runners.

7. A storage carousel as claimed in Claim 6, wherein each bogie is two-wheeled and the wheel axis is nonintersecting with the axis of the coupled pivot pin, so that the bogie trails castor fashion.

8. A storage carousel as claimed in Claim 6 or 7, wherein at least some bogies are extended to provide support at two adjacent pivot points on the chain.

9. A storage carousel comprising a plurality of trolleys coupled at their rear sides to endless loop drive means, the trolleys running on an unstable wheel base and being kept upright by the drive means.

10. A storage carousel as claimed in Claim 9, wherein each trolley has a single wheel.

11. A storage carousel as claimed in Claim 9, wherein each trolley has two wheels in tandem.

12. A storage carousel as claimed in Claims 9, 10 or 11, wherein the wheel or wheels run in a floor track.

13. A storage carousel as claimed in any one of Claims 9 to 12, wherein the drive means have at least two endless loops, synchronised and vertically spaced to connect to points near the top and bottom of each trolley.

14. A storage carousel as claimed in any one of Claims 1 to 8 and as claimed in any one of Claims 9 to 13.

15. A storage carousel substantially as hereinbefore described with reference to the accompanying drawings.