AU2004200493C1 - Animal restraint with telescopic locking assembly - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant(s): TECHNIPHARM INTERNATIONAL LTD Invention Title: ANIMAL RESTRAINT WITH TELESCOPIC LOCKING ASSEBMLY The following statement is a full description of this invention, including the best method of performing it known to me/us: Title: Animal Restraint With Telescopic Locking Assembly TECHNICAL FIELD The present invention relates generally to animal restraints, and in particular to bails or restraints for immobilizing an animal's head. More particularly the invention relates to bails that include a pair of yokes mounted for coordinated movement and including a locking mechanism for holding the yokes in an animal-restraining position.

BACKGROUND ART Bails have long been used to immobilize the heads of animals for performing animal husbandry procedures such as the administration of shots or dehorning. Typically, the bail includes a pair of yokes which squeeze the neck of the animal on opposite sides when the bail is closed and swing open to release the animal through the aperture closed by the yokes.

They are geneirally manually operated to accommodate different size animals and to accurately coordinate the closing of the bail so as to catch the animal's neck.

The prior art bails suffer from a number of deficiencies. U.S. Patent No. 5 109 802 describes a bail typical of much of the prior art, having a complicated opening and closing mechanism with many parts contributing to its expense of manufacture. The linkages used in these sorts of opening and closing mechanism necessarily have a certain amount of "play" and this detracts from the user's ability to accurately and quickly move the yokes, as well as requiring additional maintenance. There is also a consequent problem with noise, particularly after the linkage connections become worn, and this noise may disturb the animal.

To prevent unwanted opening of the yokes a locking mechanism is provided in the bail. In U.S. Patent No. 5 109 802 for example, each of the two yokes has a separate wedge-type locking device, and this also adds complexity and requires another mechanism for unlocking both yokes.

There are similar drawbacks with the multitude of other bail locking mechanisms, many of which are poorly suited to the harsh working environment in which the bail is used and require regular attention. Foreign matter coming into contact with clutch or ratchet type locking mechanisms increases wear and so decreases reliability. Hydraulic systems, whether active or passive, are also liable to suffer from contamination and are a costly alternative.

It is an object of the present invention to address the foregoing problems and to provide a simple, efficient bail which can be easily operated.

It is another object of the present invention to provide an improved locking device for use in bails or other animal restraints.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

U.S. Patent No. 5 109 802 is hereby incorporated by reference. No admission is made that this reference constitutes prior art or that it forms part of the common general knowledge in the art, in Australia or in any other country. The applicant reserves the ight to challenge the accuracy and pertinency of the cited document.

DISCLOSURE OF INVENTION According to one aspect of the present invention there is provided an animal restraint including: a pair of opposing animal-gripping members mounted for movement between an open position for allowing an animal to pass through the restraint and any one of a plurality of closed positions for gripping the animal, and a frame for supporting the animal-gripping members, wherein each animal-gripping member is mounted for rotation about a respective axis and the animal-gripping members are connected by gears for co-ordinated rotation between the open and closed positions.

Preferably the axes of rotation are parallel and vertical.

Preferably the animal restraint further includes actuating means operatively connected to an animal-gripping member for moving the animal-gripping members to the closed position upon movement of the actuating means generally in a closing direction, and locking means for locking the animal-gripping members in the closed position.

Preferably the actuating means includes a handle pivoted about a substantially vertical axis.

Preferably the handle has a vertically extending grip for improved ergonomics.

Preferably the locking means is a selectively releasable self-locking telescopic assembly including a shaft sliding inside a housing; contact means engageable with the shaft for locking the housing and shaft together; a locking member for pressing the contact means to engage the shaft, the locking member being pivotally mounted for rotation between a first position wherein the contact means are released and a canted position wherein the contact means are lockingly engaged with the shaft, and means for biasing the locking member toward the canted position.

The contact means is preferably formed separately from the locking member and comprises at least one shoe. The shoe, locking member and biasing means may be enclosed in the housing.

Preferably the restraint is a bail in which the animal-gripping members engage the neck of the animal. It will be understood, however, that the invention has-.other applications, such as crushes or squeezes where the animal-gripping members engage the sides or other parts of the animal.

The locking assembly further includes a release plunger for engagement with the locking member to release the shoe, wherein a movement of the release plunger serves to rotate the locking member to the first position. In the preferred embodiment the release plunger is slidably mounted for axial movement within the housing.

Preferably the locking assembly includes two shoes on opposing sides of the shaft in the form of a split collar which is positioned in an aperture in the locking member. The locking member is ring-shaped and includes a radially extending tab for contacting with a shoulder in the housing, such that the locking member pivots about the point of contact between the tab and the shoulder. A compression spring engages the locking member to provide the biasing means.

The locking assembly prevents unwanted reverse movement (tending to open the animalgripping members) and in the preferred embodiment the locking assembly is arranged such that the shaft is readily extensible from the housing, but automatically locks when the shaft is pushed into the housing. Alternatively, it will be understood that by reversing the direction in which the locking member is biased the locking assembly may be arranged to lock upon extension and permit ready compression.

Preferably one end of the release plunger extends from the housing and is actuable by a handle fixture, such that rotation of the handle in the closing direction presses the fixture to actuate the release plunger for unlocking the locking assembly. A degree of free rotary movement or "play" is provided between the handle and the locking mechanism and when moving in the closing direction the release plunger is actuated before the end of the free movement is reached and the locking assembly is compressed.

This invention provides a bail and a locking device for an animal restraint which are effective and efficient in operational use. It may be economically constructed, having an overall simple design which minimizes manufacturing costs. Unlike some prior art locking devices, an unlimited number of closed positions can be obtained, allowing any size animal to be closely held while allowing the operator to accurately control the restraining load applied.

BRIEF DESCRIPTION OF DRAWINGS Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which: Figure 1 is a pictorial view of a bail of the present invention, in an open position; Figure 2 is a plan view of the bail of Fig. 1, in a closed position; Figure 3 is a plan view of the bail of Fig. 1; Figure 4a is a longitudinal sectional view of a locking device of the present invention, showing it in an unlocked position; .Figure 4b is a pictorial view of the locking mechanism of the locking device of Fig.

4a; Figure 5a is a longitudinal sectional view of the locking mechanism of Fig. 4a in a locked position; Figure 5b is a pictorial view of the locking mechanism of the locking device of Fig.

Figure 6 is an exploded pictorial view illustrating the components of the locking device of Fig. 4a; Figure 7 is a plan view of the connection between the operating handle and the locking mechanism on the bail of Fig. 1, and Figure 8 is a pictorial view of the detail of Fig. 7.

7 BEST MODES FOR CARRYING OUT THE INVENTION Referring to Fig. 1, a preferred embodiment of the bail 100 is thereshown in an open position and includes a generally rectangular frame 1 for supporting a pair of opposing animal neckengaging yokes 2, 2' for pivoting movement about their respective vertical hinge axes 3, 3'.

The frame 1 and yokes 2, 2' are symmetrical about a central vertical plane (not shown) of the bail 100, and the designation prime refers to a component mirrored on the opposite side of this plane The frame 1 and bails 2, 2' are of welded steel construction, but other materials may also be used.

The bail 100 is supported on a horizontal support member 5. At either end of the support member 5 are fixed pairs of upright frame posts 6, 7, 8, 8' which are connected at their upper end portions to an angle section top frame member 9. At a front face of the frame members 8, 8' mounting brackets 10 are fixed for mounting the bail 100 at the end of an animal chute or other enclosure from which the animal will be entering the bail 100.

The yoke 2 is rotated about the vertical axis 3 by means of a control handle 4 fixed thereto.

The handle 4 has a vertically extending grip 40 allowing it to be gripped by the operator at any convenient height. The bail 100 can be assembled with the handle 4 positioned, as shown in Fig. 1 fixed to yoke 12, for left side operation or fixed to yoke 12' for right side operation (not shown). In order that the bail 100 can be more readily transported without damage, the handle 4 is removably fixed.

A bevel geared segment 11 on the yoke 2 engages a corresponding bevel geared segment 11' on the yoke 2' to co-ordinate their relative movement. The geared segments 11, 1 are formed integrally with a yoke top plate 12 which is fixed to the top frame member 9 by upper pivots 13 (Fig. Each yoke 2, 2' includes yoke stanchion bars 13-16 fixed between the top plate 12 and a bottom plate 17, with the bottom plate 17 being fixed to the horizontal support member 5 by lower pivots 18, coaxial with the upper pivots 13. The yoke stanchion bars 13- 15 serve to block the animal from attempting to pass through the bail other than between the two yokes 2, A central section of the stanchion bar 16 comprises ajaw 19, 19' which is slidably adjustable in the direction A (Fig. 2) to vary the size of the opening to accommodate large or small animals. The jaws 19, 19' are fixed by a bolt through slotted plates for adjustment such that the head of the animal to be restrained can pass through the yokes but not the animal's shoulders.

A locking device 20 to prevent unwanted opening of the yokes 2 is shown in Figs. Referring particularly to Figures 2 and 3, the locking device 20 is pivotally mounted between the frame at pivot 22 and a bracket 21 fixed to the handle 4. As the yokes 2, 2' are rotated by the handle 4 between the open and closed positions, shown in-Figs 3 and 2 respectively, the circular hard-chromed shaft 23 slides within the housing assembly 24 (see also Fig. 6) in a telescoping manner, being extended in the closed position. Once the handle 4 is released, any attempt the open the yokes by the animal serves to lock the shaft 23 and the housing 24 together, automatically locking the yokes in position until they are released by the handle 4.

Referring to Figures 4a, 4b, 5a and 5b, the locking device 20 includes a split collar comprising two shoes 25 and 26 in sliding engagement with the shaft 23. The shoes 25, 26 are held in a circular aperture in a locking plate 27, such that rotation of the locking plate 27, about an axis perpendicular to the longitudinal axis of the shaft 23, presses the shoes 25, 26 inward to grip and lock the shaft 23 (as shown in Figures 4a and 4b). The locking plate 27 pivots about a tab 29 which engages against a shoulder 30 in the housing 24 and a compression spring 28 biases the locking plate 27 toward the canted locked position. The locking device 20, by this "wedging" action provides a reverse-movement-preventing action, allowing the shaft 23 to be readily withdrawn from the housing 24 but locking when it is pushed into the housing 24. A tubular release plunger 31 (see also Fig. 6) is slidably fixed between the shaft 23 and the housing 24 for selectively unlocking the shaft 23. To unlock the shaft 23, a force applied in direction D to the outer end 33 (Fig. 4a) presses the flanged end 32 of the release plunger 31 against the locking plate 27, compressing the spring 28 and returning the plate 27 to the unlocked position.

Fig. 6 is an exploded view of the locking device 20. The housing 24 assembly protects the locking mechanism, and includes a tubular central section 34 at one end of which is fixed a mounting fixture 35, having an aperture 36, and a plunger-receiving journal 37. At the opposing endof the central section 34 is a larger diameter locking-plate receiving section, having a nosing section 41 for supporting the shaft 23. The nosing 41 also receives a seal (not shown) which seals around the shaft 23 and prevents loss of lubricating oil from the housing.

Figures 7 and 8 show the connection between the handle 4 and the locking device 20 to illustrate the manner in which rotation of the handle can actuate the release plunger 31. A boss 38 is fastened to the end fixture 35 by means of a bolt 39 fixed through the aperture 36.

The boss 38 is received in a tubular part 40 fixed to the bracket 21, which is itself rigidly fixed to the handle 4. The boss 38 is a loose fit inside the part 40 allowing a small amount of rotation of the part 40 (as well as of the bracket 21 and attached handle 4) before the locking device 20 is moved. When opening the yokes 2, 2' this small amount of rotation brings the outer face of the part 40 into contact with the outer end 33 of the release plunger 31 to unlock the shoes 25, 26 before sliding the housing 24 over the shaft 23. The b racket 21 is provided with an unused tubular partl40 for connection with the locking assembly for right side operation of the handle 4.

It is to be noted that when the yokes 2, 2' are in a neck-engaging position any forward movement of the animal e.g. through the opening closed by the yokes 2, 2' does not exert a significant yoke-opening torque on the yokes 2, 2' because the animal's shoulders are generally aligned with the axes 3, Therefore, little of the pressure on the yokes will act to push inwardly on the locking device 20 and the locking device will not be required to resist the full force of stopping the animal.

In operation of the bail 100 an operator is stationed at the handle&4. The operator will hold the yokes 2, 2' open sufficiently to at least to allow insertion of the head of the animal and so as not to unduly discourage it from attempting to pass through the bail 100. When the head of the animal passes the yokes but while the shoulders of the animal are still behind the yokes, the operator will rotate the handle 4 about its vertical axis 3 to move the yokes 2, 2' to engage the neck of the animal. The directness of the connection between the handle 4 and the yokes 2, 2' allows the operator to accurately close them. When the handle 4 is released the one-way action of the locking device will prevent opening of the yokes 2, When the operator reverses the rotation of the handle 4, the locking device 4 is first unlocked, as described above, continuing rotation then opening the yokes 2, 2'.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.

Claims (8)

1. An animal restraint including: a pair of opposing animal-gripping members mounted for movement between an open position for allowing an animal to pass through the restraint and any one of a plurality of closed positions for gripping the animal; a frame for supporting the animal-gripping members; a telescopic locking assembly for locking the animal-gripping members in the closed position, wherein the locking assembly includes: a shaft sliding inside a housing; contact means engageable with the shaft for locking the housing and shaft together; a locking member for pressing the contact means to engage the shaft, the locking member being pivotally mounted for rotation between a first position wherein the contact means is released and a canted position wherein the contact means is lockingly engaged with the shaft, and means for biasing the locking member toward the canted position.

2. An animal restraint as claimed in claim 1 wherein the contact means is lockingly engaged with the shaft by a frictional engagement.

3. The animal restraint of claim 1 wherein the contact means includes at least one shoe and the locking member and biasing means are enclosed in the housing. H:\melindaf\keep\Speci's\2004200493.doc 16/05/06 13

4. The animal restraint of claim 1 or claim 2 wherein the locking assembly further includes a release plunger for engagement with the locking member for unlocking the housing and the shaft, a movement of the release plunger serving to rotate the locking member to the first position. The animal restraint of claim 4 wherein the release plunger is slidably mounted for axial movement within the housing.

6. The animal restraint of any one of claims 1 to 5 wherein the locking assembly includes two shoes on opposing sides of the shaft in the form of a split collar which is positioned in an aperture in the locking member.

7. The animal restraint of any one of claims 1 to 6 wherein the locking member is ring-shaped and includes a radially extending tab for contacting with a shoulder in the housing, such that the locking member pivots about the point of contact between the tab and the shoulder.

8. The animal restraint of any one of claims 1 to 7 wherein a handle is operatively connected to an animal-gripping member for moving the animal-gripping members to the closed position, one end of the release plunger extends from the housing for engagement with a handle fixture, a degree of free movement is provided by a connection between the handle and the locking assembly, such that movement of the handle in the closing direction first engages the fixture to actuate the release plunger for unlocking the locking assembly before the end of H:\melindaf\keep\Speci's\2004200493.doc 16/05/06

14- the free movement is reached and the locking assembly is moved. 9. An animal restraint substantially as hereinbefore described with reference to the accompanying drawings. Dated this 16th day of May 2006 TECHNIPHARM INTERNATIONAL LIMITED By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia H:\melindaf\keep\Speci's\2004200493.doc 16/05/06