GB2169643A - Coupling for a slurry scraper - Google Patents

Abstract

A slurry scraper comprises a scraper assembly (16) and a drive chain (12) by means of which the scraper assembly may be moved over a surface to be scraped. The drive chain (12) is removably coupled to the scraper assembly (16) by means of a coupling member (10) in the form of a lever having a pin 28 mounted on it at one end for engaging a stop (14) on the scraper assembly (16) and a handle (30) at its other end. The drive chain (12) is secured to the coupling member (10) at a position intermediate its ends. The coupling member (10) is pivotable about the point of contact between the pin (28) and the stop (14) from an uncoupled position in which the chain (12) is under greater tension. A locking lug (24) is provided for locking the coupling member (10) in the coupled position. <IMAGE>

Description

SPECIFICATION Slurry scraper The present invention relates to slury scrapers, and, in particular, to scrapers of the type used to clean passageways in cow-sheds and the like.

Such scrapers are generally drawn along the length of the passageway by means of a drive chain coupled to a drive unit situated at one end of the passageway. It is usual in such systems for the chain to be coupled to the scraper at both its forward and rear ends so that the chain and scraper together form an endless loop. The scraper extends from side to side of the passageway and, as it is moved in a forward direction by the drive unit, it pushes any slurry in the passageway ahead of it to the passageway end. The drive is then reversed so that the scraper is returned to its starting position. The drive unit may be provided with suitable automatic control apparatus so that the scraper sweeps along the passageway at intervals automatically.

As will readily be appreciated, scrapers of this kind tend to obstruct the passage of tractors or other vehicles along the passageway because the scraper blades extend of necessity from one side wall of the passageway to the other. Various arrangements have been adopted in the past with a view to overcoming this difficulty.

For example, the scraper blades may be hinged to a central scraper body connected to the drive chain. With this arrangement, the scraper blades can be folded back to extend lengthways of the passageway to permit a vehicle to pass along it. One such arrangement is described in British patent no.

2047512.

However, devices of this kind are subject to a number of disadvantages. The need for a suitable hinging arrangement and means for locking the scraper blades in the operative position makes the scraper construction more complicated than it would otherwise be and, hence, more expensive. Furthermore, operation of the hinging arrangement is frequently rendered difficult by the fact that the scraper is likely to become heavily encrusted with slurry after it has been in use.

Alternatively, in order to permit passage of vehicles along the passageway the slurry scraper may be uncoupled from the drive chain and rotated bodily until the scraper blades extend lengthways of the passageway.

However, this has, in the past, been difficult to achieve because the drive chain is under considerable tension and cannot easily be released from the scraper body.

In accordance with the invention, there is provided a slurry scraper comprising a scraper assembly and a drive chain by means of which the scraper assembly may be moved over a surface to be scraped; the drive chain being removably coupled to the scraper assembly by means of a coupling member engageable with a stop on the scraper assembly so as to be pivotable about the point of contact therebetween from an uncoupled position in which the drive chain is relatively slack and a coupled position in which the drive chain is under greater tension. Means for locking the coupling member in the coupled position may be provided. Because the locking means does not directly serve to tension the chain, it can easily be released to allow the coupling member to swing to the uncoupled position.Furthermore, the tension in the drive chain actually assists in pivoting the coupling member once the locking means has been released.

With such an arrangement it is, thus, practicable to uncouple one end of the drive chain from the scraper assembly when it is desired to drive a vehicle along the passageway in which the scraper assembly is disposed.

Alternatively, it is envisaged that the point about which the coupling member moves may be so positioned with regard to the point at which the chain is secured to the coupling member as to provide an over-centring action.

In this case, no locking means would be required: the tension in the chain would act to retain the coupling member in the coupled position.

Cleariy the chain may be replaced by a rod, cable, hawser or the like. The term chain' as used throughout this specification is therefore intended to encompass all such mechanical linkages.

Preferably, the coupling member is in the form of a lever having one end engageble with the stop. Where the coupling member is in the form of such a lever, the mechanical advantage conferred by the lever configuration is of considerable assistance in putting the drive chain under tension when the coupling member is being returned to the coupled position.

It will be appreciated that a coupling arrangement of this kind is not only of use in the context of the slurry scraper described above. Indeed, such a coupling arrangement can be used whenever it is desired to removably secure a chain to some form of body where the chain is to be under tension when coupled. Thus, the invention further provides a coupling arrangement for removably coupling a chain to a body, the arrangement comprising a coupling member for securing to the chain and engageable with a stop provided on the body so as to be pivotable about the point of contact therebetween from an uncoupled position in which the chain is relatively slack and a coupled position in which the chain is under greater tension, there being provided on the body means for locking the coupling member in the coupled position.

A slurry scraper in accordance with the invention will now be described in detail by way of example with reference to the drawings in which: Figure 1 is an exploded fragmentary view of a coupling arrangement of a slurry scraper in accordance with your invention; Figure 2 shows the coupling arrangement of Fig. 1 in a partly-coupled state; and Figure 3 is a transverse sectional view along the line Ill-Ill of Fig. 1 but showing the two parts of the coupling arrangement fully engaged in the coupling position.

The coupling arrangement for a slurry scraper shown in the drawings comprises a coupling member 10 to which one end of a drive chain 12 is secured and which engages a stop 14 formed on a scraper assembly 16.

The scraper assembly 16, which may be of any convenient type and of which only part is shown in the drawings, is provided with a flat elongate base plate 18 which, when the scraper assembly is in its operative position, extends longitudinally of the passageway to be scraped. The end of the base plate 18 has a hook-shaped stop 14 welded to it. Spaced from the stop 14 along the length of the base plate 18 is an inverted U-shaped channel member 22 whose edges are welded to the base plate 18 in order to reinforce it. The channel member 22 carries a locking lug 24 which is, for example, of a known type consisting of two sections pivotally secured together. When the two sections are aligned with one another the lug 24 can be passed through a hole formed in the member to be locked in place.Once the lug has passed through the hole, the end section is pivoted to prevent withdrawal of the lug 24 through the hole. The end section of the lug 24 may be biassed by means of a spring into the angled locking position.

The coupling member 10 also incorporates a channel-shaped section 11 which is dimensioned to fit over the channel member 22 on the scraper assembly 16. The side walls of the channel section 11 are extended in a longitudinal direction to form a pair of parallel arms 26. At their ends, the arms 26 carry a pin 28 which extends transversely between the two arms 26 and is rigidly secured to them by means of welding. At the end of the coupling member 10 remote from the pin 28, a handle 30 is secured to the top surface of the channel section 11. The drive chain 12 is permanently fixed to the coupling member 10 by means of a pin 32 which passes through the end link of the chain and is secured to the arm 26. The pin 32 is located partway between the pin 28 at the ends of the arms 26 and the channel section 11.

To couple the drive chain 12 to the scraper assembly 16, the pin 28 is positioned under the stop 14 on the scraper assembly with the coupling member 10 inclined to the base plate 18 as shown in Fig. 2. The coupling member 10 is then pivoted in a clockwise direction as seen in Fig. 2 about the pin 28 which is retained in position by the hook-like configuration of the stop 14. As the coupling member is pivoted, the drive chain 12 is gradually placed under increasing tension. However, the coupling member 10 is relatively long and the drive chain 12 is secured to it relatively close to the pivot axis, that is, the pin 28. Consequently the coupling member 10 acts as a lever which provides the operator with a considerable mechanical advantage so that he can tension the chain relatively easily.Eventually, the coupling member 10 reaches the fully coupled position in which the channel section 11 of the coupling member rests on and fits over the channel member 22 on the scraper base plate 18. In this position the locking lug 24 passes through a hole 34 formed in the upper surface of the channel section 11. The end section of the lug 24 can then be rotated to hold the coupling member 10 in position.

Where it is desirable to vary the tension in, or the length of the chain, a degree of adjustment may be provided either by providing a plurality of stops 14 longitudinally spaced along the base plate or a single stop 14 which may be fixed in a number of different positions. Similarly, a degree of adjustment may be provided by arranging for the pin 32 by means of which the chain 12 is secured to the coupling member 10 to be mounted at one of several longitudinally spaced positions.

To uncouple the drive chain 12 the process is simply reversed. The two sections of the locking lug 24 are aligned with one another to allow them to be withdrawn through the hole 34. The coupling member 10 can then be pivoted in an anti-clockwise direction until the pin 28 can be removed from the stop 14. The tension in the drive chain 12 assists in the uncoupling operation so that uncoupling of the drive chain 12 is easy to accomplish.

The coupling arrangement has been described in the context of a slurry scraper but it will be appreciated that a similar arrangement can be utilised in any application where it is desired to removably couple a chain or other member under tension to a fixed body.

Claims (10)

1. A coupling arrangement for removably coupling a chain to a body, the arrangement comprising a coupling member for securing to the chain and engageable with a stop provided on the body so as to be pivotable about the point of contact therebetween from an uncoupled position in which the chain is relatively slack and a coupled position in which the chain is under greater tension.

2. A slurry scraper comprising a scraper assembly and a drive chain by means of which the scraper assembly may be moved over a surface to be scraped: the drive chain being removably coupled to the scraper assembly by means of a coupling member en gageable with a stop on the scraper assembly so as to be pivotable about the point of contact therebetween from an uncoupled position in which the drive chain is relatively slack and a coupled position in which the drive chain is under greater tension.

3. Apparatus according to claim 1 or 2 including means for locking the coupling member in the coupled position.

4. Apparatus according to any preceding claim in which the coupling member is in the form of a lever having one end engageable with the stop.

5. Apparatus according to claim 4 wherein the lever is provided with handle means for use by the operator at its other end; the chain being secured to the coupling member at a point intermediate its ends.

6. Apparatus according to any preceding claim in which the coupling member is provided with a cylindrical pin for engaging the stop, the coupling member being pivotable about the axis of the pin.

7. Apparatus according to claim 6, in which the stop is of hook-like configuration to retain the pin in position during pivoting of the coupling member.

8. Apparatus according to any preceding claim in which the axis about which the coupling member is pivotable extends transversely of the chain.

9. A coupling arrangement for removably coupling a chain to a body, the coupling arrangement being substantially as hereinbefore described with reference to the drawings.

10. A slurry scraper substantially as hereinbefore described with reference to the drawings.