NZ534384A

NZ534384A - Animal handling device

Info

Publication number: NZ534384A
Application number: NZ53438404A
Authority: NZ
Inventors: Michael Bloemen
Original assignee: Michael Bloemen
Priority date: 2004-07-28
Filing date: 2004-07-28
Publication date: 2006-05-26

Abstract

A moveable barrier assembly for use in an animal enclosure comprises a barrier 4 extending laterally between opposing sides of the enclosure, at least one drive mechanism 2 positioned on, and moveable along, each opposing side of the enclosure. The moveable barrier 4 is pivotally attached to the drive mechanism(s) 2 and the moveable barrier assembly includes at least one sensor capable of detecting at least a portion of the barrier 4 at one or more predetermined positions and/or orientations with respect to the sides of the enclosure.

Description

<div class="application article clearfix" id="description"> PATENTS FORM NO. 5 Fee No 4: $250.00 PATENTS ACT 1953 COMPLETE SPECIFICATION After Provisional No: 534384 Dated: 28 July 2004 James & Wells ref: 123656/57 ANIMAL HANDLING DEVICE I Michael Bloemen of 92 Victoria Street, Kaponga, Taranaki, New Zealand, a New Zealand Citizen do hereby declare this invention for which I pray that a patent may be granted to me, and the method by which it is to be performed to be particularly described in and by the following statement: Intellectual Property Office of N.Z. 15 SEP 2005 received TECHNICAL FIELD The present invention relates to an improved animal handling device. In particular, the present invention relates to a self-aligning moveable barrier assembly that can move within an enclosure such as a stock yard to drive animals within and through 5 the enclosure. BACKGROUND ART It is often desirable to be able to hold dairy animals in a control area prior to their being milked at a milking shed. The number of animals in the control area decreases as animals are processed through the milking shed and hence less space is needed 10 to contain them as milking proceeds. The animals are urged towards the milking shed entrance in order to ensure minimum delay between an animal leaving a milking stall and a new animal entering the stall. It is common practise for the urging of animals in the control area to be done with the use of a "backing gate". 15 Conventional backing gate systems consist of a mobile barrier which is initially located at the rear of the yard and is driven forward to encourage animals to move towards the milking shed entrance situated at the front of the control area. For example, in a circular yard, a backing gate may be partially mounted at one end on a post in the centre of the yard while the other, outside end of the gate is supported on 20 a motorised wheel. In a substantially rectangular-shaped holding area, a backing gate may be powered from drives on both sides of the gate. However, a drawback with such backing gate systems arises due to the fact that the gate assembly is required to push the entire herd of cows towards the dairy shed when only a small number of cows in the holding yard are actually required to be 25 directed into the dairy shed at any one time. 2 The requirement of the gate to push a yard of perhaps several hundred cows in a given direction places a large stress on the gate assembly and requires a significant force to move the gate in the desired direction. Consequently, such backing gate systems are prone to mechanical failures. A 5 significant mechanical problem with current backing gates is that the barrier can become misaligned or skewed to a degree where it becomes jammed or even damaged. This misalignment may be due to a number of causes including: • non-uniformity in the drive systems, • non-uniformity of the rails along which each drive system tracks, and/or 10 • impact or pressure applied by an animal(s) at a point or points on the barrier Reference throughout this specification shall be made to the use of the present invention for handling domesticated dairy animals such as cattle, sheep and goats, although it should be appreciated that the present invention can be applied to other animals or to items other than animals. 15 In particular, reference to the present invention shall be made to its use in animal enclosures such as milking shed holding areas (yards). However, it should be seen that the description is given by way of example only and should not be seen as limiting the present invention. All references, including any patents or patent applications cited in this specification 20 are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein; this reference does not constitute an admission 25 that any of these documents form part of the common general knowledge in the art, 3 in New Zealand or in any other country. It is acknowledged that the term 'comprise' may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term 'comprise' shall have an inclusive 5 meaning - i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term 'comprised' or 'comprising' is used in relation to one or more steps in a method or process. It is therefore an object of the present invention to go at least some way towards 10 addressing the foregoing problems or to at least provide the industry with a useful choice. Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only. DISCLOSURE OF INVENTION 15 A moveable barrier assembly for use in an enclosure, including a barrier extending at least partially between two substantially opposing sides of said enclosure, at least one drive mechanism positioned on and moveable along each said opposing side of the enclosure, 20 said barrier pivotally attached to said drive mechanisms, characterised in that said moveable barrier assembly includes at least one sensor, capable of detecting at least a portion of the barrier at one or more predetermined position(s) and/or orientation(s) with respect to at least one of said sides of the enclosure. 4 The present invention thus provides a means to drive a barrier from both ends, whereby any misalignment between the drive mechanisms causing the barrier to twist or skew beyond a predetermined position is detected by a sensor, enabling corrective action to be applied. 5 Throughout the present specification the term "barrier" should be understood to mean any device which at least partially blocks the egress of an animal in the enclosure and preferably will stop any animal from exiting the enclosure at any point other than the desired exit point. It should also be appreciated that "enclosure" should be understood to mean any area wherein it is required to control the movement of 10 animals. The enclosure could be any shape having at least two substantially opposing sides. For example the enclosure could be rectangular having two parallel sides, the barrier thus extending from one side to the other. Alternatively the barrier could extend between two sides of an enclosure with parallel curved sides. It will be appreciated that the present invention need not be restricted solely to 15 moving cattle and is equally suited to controlling the movement of other animals through a prescribed area. In preferred embodiments of the present invention the enclosure will be a holding yard for use with a dairy shed, an animal race, or any area where the driving of animals is required. Throughout the present specification the term "drive mechanism" should be 20 understood to include any assembly including a means for providing a motive force to the moveable barrier assembly and which is capable of causing the barrier (or at least one end thereof) to move along a side of the enclosure. In preferred embodiments of the present invention two drive mechanisms are used, one connected to each end of the barrier. Herein reference will be made to the moveable barrier assembly having 25 two drive mechanisms, however it should be appreciated that additional drive mechanisms may be incorporated to increase power output or add functionality to the present invention. 5 Also, while not as effective as two drive mechanisms, one drive mechanism may be utilised, whereby the single drive mechanism is attached to each end of the barrier via retractable chains, cables, or other lines. The drive mechanism may be positioned at one end of the enclosure and incorporate a gearing system to control the speed of 5 movement of each end of the barrier. It is envisaged that a drive mechanism used for the present invention will be powered by at least one electric, hydraulic, pneumatic or combustible fuel driven motor, however any other type of motor that is capable of delivering the required motive force to the barrier may be employed. 10 In preferred embodiments of the present invention the output of each drive mechanism provides a rotational force to at least one wheel or roller in contact with a generally horizontal surface or track along at least one of said opposing sides. In alternative embodiments said track is located along a top surface of said opposing sides of the enclosure, or located adjacent thereto. 15 Due to a number of factors, including but not limited to, variations and tolerances in individual drive mechanisms introduced during manufacture and installation, as well as variations in the three dimensional orientation of the surfaces along which each drive mechanism progresses, the relative distance between the drive mechanisms may not be constant during movement of the barrier. In existing backing gate 20 systems, damage or disruptions can occur in the operation of the backing gate if the distance between the sides of the enclosure and/or drive mechanisms varies, generating resultant stresses along the longitudinal axis of the backing gate. It is thus desirable to provide a means to accommodate a variance in the relative separation of said opposing sides of the enclosure. 25 In some preferred embodiments the barrier is configured to be able to move substantially horizontally in the plane of the barrier between the sides of the enclosure 6 to accommodate variations in the spacing between said opposing sides of the enclosure. Thus according to one embodiment the barrier is slideably attached to said drive mechanisms to permit lateral movement there-between in the plane of the barrier. 5 Existing backing gate systems are prone to mechanical failures. Significant mechanical problems with known backing gates are caused by non-uniformity of the rails or tracks along which each drive mechanism moves and/or because of an off-centre impact or pressure applied by an animal causing the barrier to slew relative to the sides of the enclosure to a degree where the barrier becomes jammed. This can 10 also lead to the drive mechanism(s) becoming damaged. These problems can be costly, in equipment repairs and the associated labour cost as well as productivity drops in the process (such as cattle milking) to which the device was driving the animals. Preferably the barrier is pivotally attached to said drive mechanisms by a hinge, substantially vertical axle mechanism or other pivot mechanism for facilitating 15 the pivoting of the barrier about a substantially vertical axis. The barrier is thus permitted to twist freely to a certain extent and therefore prevents damage as a result of twisting or bending, as would be the case in a non-pivotally attached barrier. In preferred embodiments, the moveable drive assembly has a primary direction of movement substantially parallel to the sides of the enclosure, with two reciprocal 20 directions of possible driven movement. Movement in a direction towards a given enclosure exit point shall herein be referred to as 'forward' movement and movement in the reciprocal direction shall be referred to as 'backward' movement. In the present invention at least one sensor is provided, capable of detecting at least a portion of the barrier at one or more predetermined position(s) and/or orientation(s) 25 with respect to at least one of said sides of the enclosure. Therefore when the barrier becomes misaligned, i.e. wherein the plane of the barrier forms a horizontal angle with said opposing side walls outside predetermined limits, the at least one sensor will 7 signal the drive control that the barrier is misaligned. In preferred embodiments of the present invention there is provided at least one drive control, wherein said at least one drive control receives signal(s) from said at least one sensor, determines the relative positions of the drive mechanisms from said 5 signal(s) and controls the movement of at least one of the drive mechanisms to stop the barrier from becoming misaligned or return the barrier to an aligned position after becoming misaligned. It will be appreciated that the drive control may be formed as a discrete unit, or be operational and/or functionally integrated into the sensor or drive mechanism. 10 According to one aspect, the barrier is defined as being aligned when the vertical plane of the barrier is oriented substantially perpendicular to said opposing side walls within a predetermined angular deviation threshold. Misalignment is defined as a barrier orientation outside of said deviation threshold. Existing backing gate systems cannot be applied to enclosures having curved sides 15 or portions thereof. As each end of the backing gate moves at the same speed, the end of the gate closest to the enclosure side having a smaller radius of curvature will move through a curve in a shorter time than the opposing gate end and cause the backing gate to slew and jam. The present invention overcomes this problem as the drive control is capable of varying the speed of the different drive mechanisms so that 20 the drive mechanism proximal to the enclosure side having a smaller radius of curvature moves relatively slower than the drive mechanism on the opposing side of the enclosure. In one embodiment, the speeds of each drive mechanism are controlled by the drive control from inputs from the at least one sensor indicating any misalignment. 25 The at least one sensor used within the present invention can be any of a number of types (such as proximity sensors), including mechanical, optical, ultrasonic, or any 8 other type of sensor that is capable of determining the position and/or orientation of one object with respect to another. In preferred embodiments said at least one sensor is a proximity or contact sensor. Preferably said sensor is installed at a position to detect the presence of the barrier at 5 a misalignment angular deviation threshold. The drive control then determines which drive mechanism is advanced relative to the other drive mechanism. Thus if an animal(s) movement (or lack thereof) causes the barrier to become misaligned, or if the barrier moves about the curved sides of an enclosure, or if the drive mechanisms move at different speeds to each other, or if the barrier becomes 10 misaligned for any other reason, the at least one sensor will detect the misalignment and signal the misalignment to the drive control, whereupon the drive control adjusts the speed of at least one of the drive mechanisms to correct the alignment. In some embodiments where the at least one sensor is a contact sensor, the position of said sensor may be adjusted after installation or at any other time so that the 15 operator may change the angular deviation threshold of misalignment as is needed. In some embodiments where the at least one sensor is a proximity sensor, the degree of proximity indicating barrier misalignment may be adjusted after installation or at any other time so that the operator may change the angular deviation threshold of misalignment as is needed. 20 Preferably, if a said sensor signals to the drive control that the barrier is misaligned or (in some embodiments) approaching misalignment, the drive control adjusts the relative speed of the drive mechanisms to realign the barrier. The relative speed can be adjusted in a number of ways including; • Maintaining the speed of the lagging drive mechanism while retarding the 25 speed of the leading drive mechanism until said sensor indicates that the 9 barrier is aligned. Preferably the drive control then maintains each drive mechanism at a common speed until misalignment is detected. • Causing the leading drive mechanism to reverse until the barrier is aligned. 5 • Increasing the speed of the lagging drive mechanism until the barrier is aligned. • A combination of the above. In further embodiments the drive control may utilise a time delay function after a said sensor has signalled that the barrier is no longer misaligned to allow any corrective 10 action to continue for a defined period in order that the barrier orientation is well within the angular deviation threshold limits that indicate misalignment. In some embodiments the at least one sensor provides a continual output signal indicative of the angle of orientation of the barrier rather than simply outputting a signal once the angular deviation threshold occurs. In such embodiments said at least 15 one sensor would include proximity sensors capable of detecting a level of proximity of a portion of the barrier, or alternatively the at least one sensor may be a contact sensor including a force transducer(s) to determine the proximity of a portion of the barrier based on the force incident on said contact sensor. In use, after the barrier has moved the full extent of its travel, thus driving any 20 animals in front of the barrier from the enclosure, the barrier must be re-positioned to facilitate driving of further animals. In some instances animals may be allowed to enter the enclosure behind the moving barrier. In order to drive these animals in the same direction as the previous animals, the barrier is configured to swing, slide, lift or otherwise open to allow passage animals. Such a capacity also allows the barrier to 25 pass over or above any gates openable into the enclosure. 10 In one embodiment of the present invention the barrier is capable of movement in a substantially vertical plane through operation of a lifting mechanism. In such an embodiment said lifting mechanism includes two substantially vertical guide rails provided adjacent each end of the barrier and pivotally attached to the drive mechanisms, the ends of the barrier are slideably attached to said guide rails. The lifting mechanism further includes a retraction mechanism such as a winch and line, said line attached at a first end to said winch and attached at a second end to a portion of the barrier. In one embodiment the winch is positioned at or adjacent an upper portion of the guide rails, preferably however, a pulley is provided on or adjacent an upper portion of said guide rail, the line passing over said pulley to the winch. Preferably the winch is powered by at least one of said drive mechanisms, however in other embodiments the winch is provided with a dedicated motor. Thus the barrier may be lifted in the guide rails by operating the retraction mechanism to retract or extend the line and thus raise or lower the barrier respectively. Therefore when the barrier is in a raised position an animal or gate may move underneath. In preferred embodiments the moveable barrier assembly includes at least one barrier pivoting mechanism capable of pivoting the barrier about a substantially horizontal pivoting axis. Preferably said pivoting axis is substantially parallel with the barrier and preferably located at or above the upper edge of the barrier. Thus by pivoting the barrier about said pivoting axis, preferably through approximately ninety degrees, the passage of animals under the barrier is permitted. In preferred embodiments the barrier is pivotable by at least one axle, shaft or hinge mechanism positioned at each end-space of the barrier and connecting an upper portion of the barrier to the drive mechanisms and/or adjacent portion of the moveable barrier assembly. 11 Preferably the at least one barrier pivoting mechanism includes at least one winch and at least one line attached at a first end to said winch, said line attached at a second end to a lower portion of the barrier. Said winch positioned on an upper portion of the moveable barrier assembly and operable to retract or extend the line, 5 therefore raising the barrier by pivoting said barrier about said pivot axis. When the barrier has swung about the pivoting axis to a sufficient angle, preferably ninety degrees, animals may then pass beneath the barrier and/or the entire moveable barrier assembly can be moved to any position along the perimeter of the enclosure unhindered by animals, gates or any other obstacles within said enclosure. 10 In preferred embodiments said at least one winch is powered. However in alternative embodiments the winch may be manually driven or capable of being both manually or power driven. Preferably the winch is powered by at least one of said drive mechanisms, however in other embodiments the winch is provided with a dedicated motor. 15 The line may be a rope, wire, cord, strap or other length of material of sufficient strength to lift the barrier In preferred embodiments the drive control is configured to receive a signal transmitted by a remote control device to raise, lower, start, stop or reverse the direction of movement of the moveable barrier assembly. 20 Preferably said remote control device is communicatibly coupled to the drive control by wireless means, or at least one signal line such as electrical wire or fibre-optic cable to the moveable barrier assembly. Preferably the said at least one signal line is automatically retractable about a spool at a first end and attached to a portion of the movable barrier assembly at the opposite end. Thus the signal line may retract as the 25 moveable barrier assembly moves towards the first end of said signal line and extend when said moveable barrier assembly is moving away from said first end. Because 12 the signal line moves with the moveable barrier assembly and is maintained in a taut or semi-taut state, the signal line is prevented from interfering with the operation of the moveable barrier assembly. In further embodiments power cables are provided to the drive mechanisms utilising the same spool or their own dedicated spools and also 5 connected at a first end to the spools and at a second end to the drive mechanisms. In alternative embodiments said remote control device is capable of transmitting, a radio, infrared, ultrasonic or microwave signal to the drive control, the drive control including a receiver for receipt of said signal. In preferred embodiments the remote control device is positioned adjacent to, or 10 incorporated into, the main control board of the milking shed or other structure to which the moveable barrier assembly is driving animals to. In other embodiments the remote control device is located permanently or semipermanently at a predetermined position on the enclosure or nearby structure. The predetermined position could be chosen by the user upon installation or positionable 15 as required. In preferred embodiments the remote control device is configured to transmit a signal to a receiver in the powered winch to retract or extend the line, thus the user may remotely operate the winch to raise or lower the barrier. The present invention thus provides a means to drive animals in front of a moveable 20 barrier within an enclosure, whereby any misalignment between the drive mechanisms causing the barrier to twist or skew to beyond acceptable limits is detected by a sensor, enabling corrective action to be applied by the drive control which adjusts the relative speed of the drive mechanisms to realign the barrier. Therefore it can be seen that the present invention offers many advantages over the 25 prior art. Including; Use with an enclosure having curved sides; Accommodation of 13 inconsistencies and variations in construction of the enclosure, such as distance between the sides of the enclosure; Overcoming disruptions in the alignment of the barrier as a result of an animal pushing off-centre against the barrier will not damage, or prevent the operation of the present invention. 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 diagrammatical representation of a plan view of a preferred embodiment of the moveable barrier assembly Figure 2 is a diagrammatical representation of an end view of the assembly of figure 1 including a gate and a further side support structure through section "A-A". Figure 3 is a diagrammatical representation of a side view of the moveable barrier assembly shown in Figure 2 through section "B-B" and attached to one side of an enclosure. BEST MODES FOR CARRYING OUT THE INVENTION With reference to figures 1-3 there is provided a moveable barrier assembly as generally indicated by arrow 1. The moveable barrier assembly (1) extends between two substantially opposing sides (3) of an enclosure and includes two drive mechanisms (2, 2') located upon the sides (3) of the enclosure within which the barrier (4) is to drive animals. 14 With respect to figures 1 & 2, the two drive mechanisms (2, 2') include motors (5) to power drive wheels (6) which are in contact with and ride along the sides (3) of the enclosure. The motors (5) may incorporate a gearbox fitted in order to control the rotational velocity of the drive wheels (6) with respect to the rotational velocity of the 5 motor's shaft. If a situation occurs where a drive mechanism (2) or (2') at one end of the barrier (4) becomes misaligned relative to the other drive mechanism (2') or (2) then the barrier (3) can become misaligned. The barrier (4) is defined as being aligned when the vertical plane of the barrier (4) is oriented substantially perpendicular to said opposing 10 side walls (3) within a predetermined angular deviation threshold. Misalignment is defined as a barrier orientation outside of said deviation threshold. This may occur for example if the barrier (3) is pushed off-centre by an animal such as a cow. To prevent damage as a result of such a misalignment the barrier (4) is slideably and rotateably attached to the drive mechanisms (2, 2') by two shafts (7) inserted into sleeves (11) 15 that are connected to the drive mechanisms (2, 2') via vertical hinge mechanisms (8) which accommodate rotation of the barrier (4) about a vertical axis and thus prevent damage resulting from such a rotation. The barrier (4) is also able to move laterally with respect to the sides of the enclosure as indicated by arrows 10 and 10' to allow for variations in the spacing between the sides (3) of the enclosure and to prevent 20 stress on the barrier (4) if the barrier (4) becomes misaligned. The shafts (7) are also rotateable in the sleeves (11), thus the plane of the barrier (4) may rotate about the pivot axis through the shafts (7) to facilitate the raising and lowering of the barrier (4). The drive mechanisms (2, 2') are secured from lateral movement on the sides (3) of the enclosure by the use of rollers (9) which fit either side of the top of the sides (3) of 25 the enclosure to ensure that the drive wheels (6) are kept in alignment with the sides (3) of the enclosure during the movement of the moveable barrier assembly (1). With respect to Figures 1 & 3 the moveable barrier assembly (1) contains two 15 sensors (12) (such as contact or proximity sensors) which will be triggered when the barrier reaches an orientation angle at the angular deviation threshold. This angular deviation threshold can be set by adjusting the position or level of proximity of the contact or proximity sensors (12) respectively. 5 When one of the sensors (12) has been triggered it will send a signal to the drive control (13) indicating the barrier (4) is misaligned in order that the drive control (13) can initiate remedial action to ensure that the amount of misalignment is reduced until it is within the angular deviation threshold. The drive control (13) then adjusts the relative speed of the drive mechanisms (2, 2') 10 to stop misalignment or realign the barrier (4) if the barrier (4) has become misaligned. The drive control (13) will then slow or stop the leading drive mechanism, (2) or (2'), while maintaining the speed of the lagging drive mechanism (2' or 2 respectively) until the barrier (4) is realigned. The drive control (13) will then maintain the drive 15 mechanisms (2, 2') at a common speed. Alternatively, the drive control (13) may reverse the direction of the leading drive mechanism, (2) or (2'), and/or increase the speed of the lagging drive mechanism (2' or 2 respectively) the barrier (4) is no longer misaligned. In one embodiment the drive control (13) may utilise a time delay function after a said 20 sensor (12) has signalled that the barrier (4) is no longer misaligned to allow any corrective action to continue for a controlled period of time in order that the barrier (4) has an angle of orientation within the angular deviation threshold limits that indicate misalignment. With respect to Figures 1 & 3, in many typical backing gates, it may be necessary for 25 the barrier (4) to be lifted in order to allow animals or gates to be passed under the 16 barrier (4). This is particularly the case when the moveable barrier assembly (1) is returned from its end position to its start position, or if animals are positioned behind the barrier (4). In such circumstances the barrier (4) may be raised by the use of at least one winch 5 (14) that is controlled by at least one of the motors (5); however in some cases the winch (14) may have its own motor. A line (15) is attached at a first end (16) to the winch (14) and attached at a second end (17) to a lower portion of the barrier (4), thus the line (15) may be retracted by the winch (14) to apply a torque to the barrier (4) about a pivoting axis X-X through, and parallel to, the shafts (7) and therefore 10 raise the barrier (4) as indicated by arrow (19). In Figure 1 the drive controls (13) are shown as being contained within the same housing as the motors (5) of the drive mechanisms (2, 2'), however this is only one representation of its location as it is equally feasible for it to be contained at any other location. 15 Thus it can be seen that the present invention overcomes the significant disadvantages inherent in existing backing gate systems by incorporating at least one sensor (12) and drive control (13) to correct any misalignment of the barrier (4) or realign the barrier (4) and thus prevent damage to the barrier (4) as a result of such misalignment. The inclusion of sleeves (11) positioned on the drive mechanisms (2, 20 2') for receipt of shafts (7) of the barrier (4) allow lateral movement of the barrier (4) and ensure that minimal stress is incident on the barrier (4) as a result of any skew and/or variation in relative distance between the two sides (3) of the enclosure in addition to facilitating the raising and lowering of the barrier (4). Aspects of the present invention have been described by way of example only and it 25 should be appreciated that modifications and additions may be made thereto without departing from the scope thereof. 17 </div>

Claims

<div class="application article clearfix printTableText" id="claims"> WHAT IS CLAIMED IS:

1. A moveable barrier assembly for use in an enclosure, including; a barrier extending laterally between two substantially opposing sides of said enclosure, at least one drive mechanism positioned on and moveable along each said opposing side of the enclosure, said barrier pivotally attached to said drive mechanisms, characterised in that said moveable barrier assembly includes at least one sensor capable of detecting at least a portion of the barrier at one or more predetermined position(s) and/or orientation(s) with respect to at least one of said sides of the enclosure.

2. The moveable barrier assembly as claimed in claim 1 wherein the barrier is pivotally attached to said drive mechanisms by a substantially vertical pivot mechanism for facilitating the pivoting of the barrier about a substantially vertical axis.

3. The moveable barrier assembly as claimed in claim 1 or claim 2 wherein the barrier is aligned when the vertical plane of the barrier is oriented substantially perpendicular to said opposing side walls within a predetermined angular deviation threshold.

4. The moveable barrier assembly as claimed in any of the previous claims including at least one drive control, wherein said drive control receives signal(s) from said at least one sensor, determines the relative positions of the drive mechanisms from said signal(s) and controls the movement of at least IntSibctual Propuriy Office of H.Z. 18 2 5 JAN 2008 one of the drive mechanisms to stop the barrier from becoming misaligned or return the barrier to an aligned position after becoming misaligned.

5. The moveable barrier assembly as claimed in claim 4 wherein the output of each drive mechanism provides a rotational force to at least one wheel or roller in contact with a generally horizontal track along at least one of said opposing sides.

6. The moveable barrier assembly as claimed in claim 5 wherein said track is located along a top surface of said opposing sides of the enclosure, or located adjacent thereto.

7. The moveable barrier assembly as claimed in any of claims 4-6 wherein the barrier is configured to be able to move substantially horizontally in the plane of the barrier between the sides of the enclosure.

8. The moveable barrier assembly as claimed in claim 7 wherein the barrier is slideably attached to said drive mechanisms to permit lateral movement therebetween in the plane of the barrier.

9. The moveable barrier assembly as claimed in any of claims 4-8 wherein said at least one sensor is a proximity or contact sensor.

10. The moveable barrier assembly as claimed in claim 9 wherein the at least one sensor is installed at a position to detect the presence of the barrier at a misalignment angular deviation threshold.

11. The moveable barrier assembly as claimed in any of claims 4-10 wherein the at least one sensor provides a continual output signal indicative of the angle of orientation of the barrier.

12. The moveable barrier assembly as claimed in claim 11 wherein said at least 19 CMm cf MX ' \ 2C ! -A * ? I;RECEIVFR J;one sensor is a proximity sensor capable of detecting a level of proximity of a portion of the barrier.;

13. The moveable barrier assembly as claimed in claim 11 wherein the at least one sensor is a contact sensor including a force transducers) to determine the proximity of a portion of the barrier based on the force incident on said contact sensor.;

14. The moveable barrier assembly as claimed in any of claims 4-13 wherein said moveable barrier assembly is configured to selectively raise and lower the barrier.;

15. The moveable barrier assembly as claimed in claim 13 or claim 14 wherein the moveable barrier assembly includes at least one barrier pivoting mechanism capable of pivoting the barrier about a substantially horizontal pivoting axis.;

16. The moveable barrier assembly as claimed in claim 15 wherein said barrier pivoting mechanism includes at least one axle, shaft or hinge mechanism positioned at each end of the barrier and connecting an upper portion(s) of the barrier to the drive mechanisms and/or adjacent portion of the moveable barrier assembly.;

17. The moveable barrier assembly as claimed in claim 15 or claim 16 wherein the barrier pivoting mechanism includes at least one winch and at least one line attached at a first end to said winch, said line attached at a second end to a lower portion of the barrier, said winch operable to retract or extend the line.;

18. The moveable barrier assembly as claimed in claim 17 wherein said winch is powered by at least one of said drive mechanisms.;

19. The moveable barrier assembly as claimed in any of claims 4-18 wherein the;20;Gffica cf ~a.z. 2 5 JAN 2003;drive control is configured to receive a signal indicating to raise, lower, start, stop or reverse the direction of movement of the moveable barrier assembly.;

20. The moveable barrier assembly as claimed in claim 19 wherein said signal is transmitted by a remote control device.;

21. The moveable barrier assembly as claimed in claim 20 wherein said remote control device is communicatibly coupled to the drive control via at least one signal line.;

22. The moveable barrier assembly as claimed in claim 21 wherein said remote control device is communicatibly coupled to the drive control via wireless means.;

23. The moveable barrier assembly as claimed in any of claims 20-22 wherein said remote control device is positioned adjacent to, or incorporated into, the main control board of the milking shed or other structure to which the moveable barrier assembly is driving animals to.;

24. A method of automatic operation of a moveable barrier assembly as claimed in any of claims 4-23 wherein if a said sensor indicates to the drive control that the barrier is misaligned, the drive control adjusts the relative speed of the drive mechanisms to realign the barrier.;

25. A method of automatic operation of a moveable barrier assembly as claimed in any of claims 4-23 wherein if a said sensor indicates to the drive control that the barrier is approaching misalignment, the drive control adjusts the relative speed of the drive mechanisms to prevent misalignment of the barrier.;

26. A method of automatic operation to adjust the relative speed of the drive mechanisms as claimed in claim 24 or claim 25 wherein the drive control;;a) maintains the speed of the lagging drive mechanism while retarding the speed of the leading drive mechanism until said sensor indicates that the barrier is aligned,;b) the drive control then maintains each drive mechanism at a common speed until misalignment is detected.;

27. A method of automatic operation to adjust the relative speed of the drive mechanisms as claimed in claim 24 or claim 25 wherein the drive control;;a) maintains the speed of the lagging drive mechanism,;b) reverses the direction of movement of the leading drive mechanism c) the drive control then maintains each drive mechanism at a common speed until misalignment is detected.;

28. A method of automatic operation to adjust the relative speed of the drive mechanisms as claimed in claim 24 or claim 25 wherein the drive control;;a) increases the speed of the lagging drive assembly until the barrier is no longer misaligned,;b) the drive control then maintains each drive mechanism at a common speed until misalignment is detected.;

29. A method of automatic operation to adjust the relative speed of the drive mechanisms as claimed in any of claims 24 to 28 wherein the drive control utilises a time delay function after the at least one sensor has signalled that the barrier is no longer misaligned to allow any corrective action to continue for a controlled period of time in order that the barrier is well within the angular deviation threshold that indicates misalignment.;until said sensor indicates that the barrier is aligned,;Cifieo cf;22;2C I s- M! J JHii IteUQ;

30. A method of operating a moveable barrier assembly as claimed in any of claims 24 to 29 comprising any combination of the following processes;;a) moving the moveable barrier assembly forward,;b) stopping movement of the moveable barrier assembly,;c) reversing the direction of the moveable barrier assembly.;

31. A method of operating a moveable barrier assembly as claimed in any of claims 14-18 including the steps of;;a) moving the moveable barrier assembly forward to drive animals to an outlet of the enclosure,;b) raising the barrier,;c) reversing the direction of the moveable barrier assembly,;d) lowering the barrier and repeating steps a to c.;

32. A moveable barrier assembly substantially as herein before described, with respect to, and as shown in the accompanying drawings.;

33. A method of automatic operation of a moveable barrier assembly substantially as herein before described, with respect to, and as shown in the accompanying drawings.;Michael Bloemen by his Attorneys;JAMES & WELLS;Office of / >. J;23;2 El ! ' * ; J J fill £MQ r ec e i ved </div>