GB2140665A - Gate device - Google Patents

Abstract

A rear gate device for an animal enclosure, such as a passage or stall or cattle crush, comprises a closure such as a bar 6 which in the closed position extends across the entrance and moves from an open position by hinging about an axis 6a such that it is not moved appreciably into the length of the passage or stall and can fall by gravity immediately behind the rump of an animal that has raised the bar and passed beyond it. <IMAGE>

Description

SPECIFICATION Gate device for animal enclosures This invention relates to a gate device for cattle and other domesticated animals.

In the design and operation of cattle crushes and similar apparatus where animals are constrained to follow a desired path, such as abreast milking parlours, there is often a requirement that, when an animal has taken the desired path and reached a predetermined position along that path, the animal should be prevented from backing out again. This has often been achieved by the use of a spring-loaded gate swinging on a vertical hinge or, in the case of a milking parlour, by a chain which is hooked across behind the animal by the person in charge of the operation. Both methods are attended by certain disadvantages. For example, in the first case the length of the structure has to be increased by the gate radius and in the second case the placing and securing of the chain is an additional operation that has to be performed.

According to the invention in a gate device for use at an entrance to a passage or stall for animals a bar is arranged to extend across such entrance and is hinged about an axis such that it is not moved appreciably into the length of the passage or stall and can fall by gravity immediately behind the rump of an animal that has raised the bar and passed beyond it. A fixed stop may be provided to prevent the bar being raised as far as dead centre so that it can always return entirely by gravity, or, if further movement is required, a resilient stop can be used so as to return the bar to a position where gravity can take over.

The invention finds particular appiication in abreast milking parlours where a cow is admitted to a raised milking position defined by side rails at least on one side and by a forward door which is opened only after milking. The gate of the invention is placed so as to confine the cow in the correct position for milking, and it has been found that cows confronted with an obstacle of this kind usually adopt a head-down position, or at least maintain their heads level as they climb on to the platform. This, combined with the step-up, enables the bar to ride up the animal's neck and back and over its rump, when it drops down to a position which effectively prevents the animal from backing out.

In a preferred form of the invention the bar is pivoted on a hinge and axis of which lies parallei to the direction of movement of the animal and the bar may be integral with a hinge portion at right angles to it and arranged for rotation between limits in a tubular housing. In one such arrangement the tubular housing is provided with clamping strips which extend over the top two rails and enable the bar and hinge structure to be attached to an existing installation. It also provides for adjustment to suit the height of animals being dealt with.

In another form of the invention the bar is part of a somewhat U-shaped member, the open end of which is arranged to lie across the path to be taken by an animal, the member being normally approximately horizontal and extending rearwardly from pivot points at the open end of the U so that the joining portion of the U forms a bar type gate across the path. The member is raised by the animal entering the path and drops down behind it so that, in addition to rearward movement being prevented by the joining portion of the U, sideways movement is restrained by the sides of the U.

In the case of some milking parlours, such as abreast parlours, the stall is on a raised platform forming the floor of the stall and the step extends along the back and around one side of this platform. It can sometimes happen that a cow will back down to one side and get off the platform, and according to a feature of the invention a chain or wire rope or other retainer is provided extending from the free end of the bar to a fixed part of the framework of the stall forward of the free end.

In a further form of the invention the retainer is attached to the stall by a fastening which permits movement in a transverse plane so as not to restrict upward movement but at the same time restrain any rearward or sideways movement or force. This may be achieved by using a long staple which is preferably arranged at an angle in said plane.

In the event that the mass of the structure becomes of importance, it may be reduced by the use of special lightweight materials such as duralumin or stainless steel tube, or the mass may be counterbalanced by springs or counterweights.

According to another feature of the invention the movement of the bar is used to initiate the operation of ancillary apparatus such as sprays for applying materials to the animals, for example fly repellants.

Examples of gate devices according to the invention are now described in relation to the accompanying drawings in which Figure 1 shows the rear part of a milking parlour stall to which a unitary gate device has been attached, Figure 2 shows a modified form of the gate device of Figure 1, Figures 3 and 4 are diagramatic plan views of a milking parlour stall to which a modified form of the invention has been fitted, Figures 5 and 6 are diagramatic end elevations corresponding to Figures 4 and 5, and Figure 7 is a view similar to Figure 1 illustrating a further form of gate device.

The milking parlour is not shown in its entirety since it is well known per se. From Figure 1 it will be seen that it includes a raised platform 1 which has a stall composed of side rails 2 and 3, and these may be supplemented by lower side rails 2a and 3a respectively. In a conventional structure a cow to be milked enters the stall by stepping up on to the platform 1 and stands with its rump about in line with vertical posts 4 and 5 to which the rails are attached. In this position a cluster of teat cups of a milking machine is attached and to prevent the cow backing off a chain is passed across from one post and fastened to a hook on the other side, either on the other post or on some convenient part of the structure. The invention, however, provides an automatic gate to take the place of the chain.The gate comprises a bar 6 which may be solid or tubular and in the example shown is bent at right angles at one end to form a shaft 6a journalled in a tube 7 which forms a bearing for the shaft.

The tube 7 is attached to the rails by brackets 8 which are welded to it, and by clamping plates 9 which are bolted to the brackets 8 so as to embrace the top two rails. The plates and brackets are adjustable up and down by using alternative holes, so as to cater for animals of different heights.

The free end of the bar 6 may be curved forwards as shown to improve the security of holding the animal in position, for example in cases where the stall is open on the side opposite that to which the gate device is attached, and, if desired, additional strength to resist rearward movement may be given by a web 11 welded across the angle of the bar. As a further strengthening measure a projection 12 may form part of the post 5 on the opposite side of the stall from the hinge to serve as a limit stop in the event that sufficient force is applied to the bar to cause it to bend.

The shaft 6a is located in the tube 7 by a pair of studs which are screwed into it and the heads of which run in radial slots 10 in the tube 7. The slots 10 are dimensioned to arrest the bar 6 in its downward path when it reaches a horizontal position and to permit the bar 6 to be raised to a position somewhat short of the vertical. Gravity return of the bar, after it has been raised by an animal passing below it, is thus assured. If, however, further upward movement of the bar 6 is required in some special case a resilient stop may be used to return the bar to a position where gravity can once again become effective.

A modified form of the above construction is shown in Figure 2 of the drawings, where a stall has fixed rails 20, 21 on one side only. In this case the bar 25 is provided with a forwardly extending arm 26 which, when the cross portion 25a of the bar 25 is in its lowered position, effectively encloses the animal at the rear and on the side remote from the rails 20, 21. In order to provide rigidity to the structure when in the lowered position the forward end of the arm 26 may engage an upward facing fork 27 on the fixed frame to prevent any sideways movement, and a cross pin 28 in the end of the arm 26 may be used to restrain rearward movement. The extra weight introduced by increasing the size of the bar member may be partially or completely counterbalanced by a spring or counterweight.

In Figures 4 to 7 of the drawings the stall is represented by the rectangle 101 and the bar 1 02 is bent at right angles and hinged along one side of the stall as at 103. A chain 104 is attached to the free end of the bar 102 and extends along a staple 105 so that when the bar 102 is raised by an animal entering the stall it slides up the staple and so does not restrict the upward movement of the bar. When, however, the animal is in the stall the bar is lowered and the chain ring slides to the bottom of the staple. The chain is then reasonably taut across the left hand side of the stall to restrain the animal from backing off the platform to that side. The operator performing milking operations, however, is not impeded since the chain is flexible and will follow, the animal's movement if he pushes on the side of the animal for any reason. In cases where it is acceptable to have the animal more restrained, it is not essential to use a flexible element and the chain may be replaced by a bar and this may be made to extend in the direction of its length if desired.

Claims (9)

1. A gate device for use at an entrance to a passage or stall for animals comprising a bar arranged to extend across such entrance and hinged about an axis such that it is not moved appreciably into the length of the passage or stall and can fall by gravity immediately behind the rump of an animal that has raised the bar and passed beyond it

2. A gate device according to claim 1 wherein a stop is provided to prevent the bar achieving a dead-centre position, so that it can return to the closed position entirely by gravity.

3. A gate device according to claim 2 wherein a resilient stop is used.

4. A gate device according to any one of the preceding claims wherein the bar is pivoted on a hinge the axis of which lies parallel to the direction of movement of the animal.

5. A gate device according to any one of the preceding claims wherein the bar is part of a Ushaped element one side limb of which is hinged to a structure which is arranged for attachment to an existing stall or passage.

6. A gate device according to any one of the preceding claims wherein the distal end of the bar has a forwardly returned portion to restrain sideways movement of an animal.

7. A gate device according to claim 6 wherein the distal end has a restraining element extending between it and a forwardly situated part of the fixed framework.

8. A gate device according to claim 7 wherein the element is a flexible element such as a wire or chain.

9. A gate device according to claim 7 or claim 8 wherein the restraining element is secured at its forward end by a fastening which permits that end to move out of the path of an incoming animal.

1 0. A gate device according to claim 9 wherein the fastening comprises a staple and ring.

1 A gate device according to claim 10 wherein the staple is arranged to extend upwards in a plane approximately at right angles to the direction of movement of animals through the passage or stall.