GB2113794A - Clutch-actuating means for a roller-conveyor driving mechanism - Google Patents

Abstract

A driving mechanism for a conveyor-roller 32 comprises, between a rockable clutch-actuating element 14 and an axially displaceable clutch element 35, a cam means comprising a part 21 having a cam slot or groove 22, inclined in relation to the axial direction, and a projection 23 provided on another cam part 13 and engaged in a said slot or groove after the fashion of a bayonet connection, the said cam parts being operatively associated with said actuating element and clutch element. Suitably the clutch is a positive clutch comprising clutch halves 31, 35 of complementary frusto-conical shape. The element 14 may be pivoted by longitudinal displacement of an actuating link bar 15. The bar 15 may be responsive to a load sensor and cause actuation of the clutches of several rollers. <IMAGE>

Description

SPECIFICATION Improvements relating to roller-conveyor driving mechanism This invention concerns improvements relating to driving mechanism for rollers conveyors, particularly such conveyors of the kind adapted for being employed in an accumulating role.

Conveyors of this kind commonly comprise, for each load-conveying roller or each of certain said rollers of a conveyor, a clutch device by which the roller can be controllably driven from a continuously running driving means such as a chain. Such mechanism may be subject to wear, involving the necessity for not-infrequent examination and periodical attention. It is an object of the present invention to provide a clutch for the above purpose which is less vulnerable with respect to wear and which permits of positive cam-action control of both clutch engagement and clutch disengagement without the necessity for spring or other, additional, return means.

According to the invention, a conveyor-roller driving mechanism, particularly for an accumulating conveyor, comprises, between a turnable actuating element such as a rockable lever and an axially displaceable element of a clutch device, such as one half of a dog or other positive clutch, a cam means comprising at least one cam slot or groove, inclined in relation to the axial direction, in a peripheral body or surface of a cam part or surface and at least one projection, such as a substantially radial peg, provided on another cam part and engaged in the said slot or groove or a respective said slot or groove, which cam parts are disposed to permit of relative turning movement and axial movement between them and are operatively associated with the said actuating element and said clutch element.The engagement action may be similar to that obtained between the pins and the lamp-socket slots of a bayonet connection. It is an advantageous characteristic or such cam means that both clutch engagement and clutch disengagement can be produced by positively effected movement and without recourse to sprint or like return means.

One embodiment of the invention is illustrated by way of example in the accompanying drawings in which Fig. 1 is a diametrical vertical section through a clutch-actuating mechanism, including cam means, and adjacent parts of a conveyor roller.

Fig. 2 is an end view to a larger scale, Fig. 3 is a side view of a collet body and arm employed in the mechanism and Fig. 4 is an exploded scrap view of the cam means.

In this example, one half of a dog-clutch device with a clutch element 31 offrusto-conical form is secured in one end of a respective load-carrying conveyor roller 32, for instance and as shown by swaging the adjacent edge 33 of the cylindrical shell 34 of the roller over a hub portion 311 of the said clutch half.

By the hub-portion 311 and a hub member 36 (Fig. 1) at the other end of the roller 32, the roller is supported by roller bearings 37 on a nonrotatable shaft 20 whose one end is secured by a stud 38 in a longitudinal side-frame member 1 7 of the conveyor. The other end of the shaft 20 may be supported in a similar side-frame member (not shown) on the other side.

The other clutch half 35, which is of complementary frusto conical shape, is formed on an annular member 2 which is also formed with a ring of chain-sprocket teeth 3. A hub portion 4 of the clutch half 35 is located freely rotatably and with slight axial play in a wide annular channel 5 on a collet body 6. As shown in Fig. 3, the body 6 has four equally spaced slots 7 with semi-circular ends. Arcuate ends of the collet-body portions between the slots 7 are formed with end lips 8 of tapered cross section. For assembling the collet body 6 with the clutch member 2, the latter is pushed over the former until it engages in the channel 5 where it is located between shallow arcuate shoulders 9 formed by the lips 8 and a deeper shoulder 10 at the other end.The latter shoulder is formed by a hub portion 11, of larger external and internal diameters, which is secured to an annular part 13 of an arm 14 extending radially from the axis of the clutch roller. Near its outer end, the arm 14 is pivotally connected by a pivot 1 6 of hollow-fastener type, to an actuating link bar 1 5. By longitudinal displacement of the bar 15, the arm 14 can be rocked between extreme positions indicated in Fig. 2 by full lines at 1 4 and by chain lines at 14' respectively.

The components already referred to are thus located within a substantially C-section side-frame member 1 7 whose upper flange 18 and lower flange (not shown) serve to support guide blocks 19' for upper and lower flights of a chain 19 moving within the C-section, as well as affording partial protection in relation to driving and other moving components and also supporting the nonrotating shaft 20 on which the one clutch half 35 and the roller 32 with the other clutch half 31 are rotatable. In these respects, the arrangement may be similar to that described and illustrated in our Patent Specification No. 2048812.Gontrol of clutch engagement and disengagement, is, however, not exercised by cam means on a longitudinally displaceably guard plate, but by cam means of the nature of a bayonet type of connection comprising a socket 21 with parthelical slots or channels 22 (Fig. 4) engaged by diametrically opposed pegs 23 projecting radially inwardly from the hub part 13 of the arm 14. The socket 21 is held against turning by an axial projection 25 engaged in an opening 26 in the frame member 1 7. The assembly 6, 14 on the other hand is free to be turned in relation to the socket 21. On angular movement of the arm 14 by the bar 15, the pegs 23 will move in the socket slots 22 and displace the assembly 6, 14, together with the clutch half 35, axially towards the other clutch half 31 fast with the roller 32, i.e. towards the left in Fig. 1.The clutch will thus be engaged by an axial movement positively applied to the clutch half 35 and the roller 32 will be driven from the chain 19, which is in constant engagement with the sprocket teeth 3. On reverse angular movement of the arm 14, the slots 22 will impart opposite axial movement to the pegs 23 and the clutch half 35 so that the clutch will be disengaged, again by a positively applied movement.

The link bar 1 5 may be controllable in known manner by a load sensor, projecting upwardly between carrying rollers. A bar 1 5 may control a plurality of rollers by means of their respective clutches in a manner dependent on operational requirements.

The several elements of the mechanism, namely the clutch/pinion unit 2 - 4, the collet/arm unit 6, 14 and the socket 21 may be made from a nylon material such as maranyl or nylatron (trade marks) or other plastics material.

As shown, the arm 14 and collet 6 are made as separate parts secured together by screws 1 2.

Advantageously however the parts 6 and 14 are integrally moulded in one piece.

In the above-described embodiment of the invention, both the actuating element comprising the part 14 and the clutch element comprising the clutch half 35 are operatively connected to the cam part comprising the pegs 23 in the hub part 13, while the cam part comprising the socket 21 and slot 22 is stationary. In a possible alternative arrangement of cam means, however, the actuating element could be operatively connected to one part of the cam means, e.g. a turnabie but not axially displaceable socket 21 with slots 22, while the other part of the cam means, e.g. an axially displaceable part with pegs 23 could be operatively connected to the clutch half 35.

Claims (5)

1. Conveyor-roller driving mechanism comprising between a turnable actuating element and an axially displaceable element of a clutch device, a cam means comprising at least one cam slot or groove, inclined in relation to the axial direction, in a peripheral body or surface of a cam part or surface and at least one projection provided on another cam part are engaged in a said slot or groove, which cam parts are disposed to permit of relative turning movement and of relative axial movement between them and are operatively associated with said actuating element and said clutch element.

2. Mechanism according to claim 1 , wherein the said elements are both operatively associated with the same one of the said cam parts.

3. Mechanism according to claim 1 or 2, wherein the clutch is a positive clutch.

4. Mechanism according to claim 1,2 or 3, wherein the clutch comprises clutch halves of complementaryfrusto-conical shape.

5. Conveyor-roller driving mechanism substantially as hereinbefore described with reference to the accompanying drawings.