AU2008100046A4 - Stock drafting device - Google Patents

Description

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C<K AUSTRALIA SPatents Act 1990 COMPLETE SPECIFICATION

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Innovation Patent 00 Applicant(s): PAUL SHEWEN CO PTY LTD Invention Title: STOCK DRAFTING DEVICE The following statement is a full description of this invention, including the best method for performing it known to me/us: 00 2 STOCK DRAFTING DEVICE FIELD OF THE INVENTION The present invention relates to a device for separating a herd of animals into two or more herds.

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BACKGROUND OF THE INVENTION The task of separating a herd of animals into two or more herds has traditionally being carried out in 00 10 paddocks or stockyards.

SStockyards used to carry out this task commonly include a straight passageway or raceway that is defined by a pair of parallel fences and a drafting assembly positioned in the raceway for separating animals into two or more herds. The drafting assembly is typically in the form of an opening in one of the fences of the raceway that leads to a holding yard and a gate that is pivotally mounted to the other fence opposite to the opening.

In use, the gate can be either manually or by other suitable means moved across the raceway so as to direct an animal moving along the raceway to pass through the opening and thus into a holding yard off the opening.

In the situation in which the animal in the raceway is to be kept separate from the herd in the holding yard off the opening raceway, the gate is pivoted to a position parallel to the fences which allows the animal to continue along the raceway into another holding yard.

A difficulty with this type of drafting assembly is that an animal can pass through the opening in the fence without the gate being pivoted across the raceway.

Another difficulty is that an animal can stray from the holding yard off the opening in the fence into the raceway and drafting assembly.

More recently, attempts have been made to address these difficulties by a drafting gate that includes a pair of the gates that can be pivoted in parallel relationship using hydraulic cylinders.

Nh\Melbourne\Cases\Patent\49000-49999\P49169.AU.3\Specis\P49169.AU.3.doc 15/01/08 00 3 O It is an object of the present invention to provide an alternative device for separating a group of animals into two or more groups.

SUMMARY OF THE INVENTION IAccording to the present invention there is provided a device in the form of a station for separating animals into two or more groups, the station capable of being used in association with animal corral or other 00 10 live-stock holding equipment including vehicles for Stransporting live-stock, the station including: a) an entrance through which animals can enter the station; b) two or more exits through which the animals can exit the station and thereby be directed into separate groups; c) a first moveable obstruction means that can be operated to selectively open and close the entrance of the station and thereby allow an animal to enter the station; d) a second moveable obstruction means that can be operated to selectively open and close the exits so as to allow an animal to exit the station from one of the exits; and e) a detecting means for detecting when an animal has entered the station by passing through the entrance or for when the animal has exited the station by passing through one of the exits.

According to an embodiment of the present invention there is provided a stock drafting station for separating animals into two or more groups, the station capable of being used in association with animal corral or other live-stock holding equipment including vehicles for transporting live-stock, the station including: a) an entrance through which animals can enter the station; N \Melbourne\CseS\Patent\4900O-49999\P49169.AU.3\Specia\P49169AU.3.doc 15/01/08 00- 4 Sb) a first moveable obstruction means that is Soperable to selectively open and close the entrance of the station and thereby allow an animal to enter the station; IN c) two or more exits through which animals can exit the station, wherein two of the exits are in the form of Iopposite side exits that face each other; d) a pair of gates of which at least one gate is located at each respective exit and is operable to open and close the respective exit; and 00 10 e) detecting means suitable for detecting either one or a combination of situations in which i) an animal has entered the station by passing through the entrance and/or ii) an animal has exited the station by passing through one of the exits.

Preferably, the detecting means contains separate first and second detecting means, whereby the first detecting means is capable of detecting when an animal has entered the station by passing through the entrance, and the second detecting means is capable of detecting when an animal has exited the station by passing through one of the exits.

In use, when the first detecting means detects that an animal has past through the entrance of the station, the first obstruction means can be closed to prevent the animal from exiting the station via the entrance, and in addition, prevent another animal from entering the station prior to the animal in the station exiting the station. The second obstruction means can be operated to open and/or close the exits so that the animal in the station is directed to join a desired group. When the second detecting means detects that the animal has past through the desired exit, the exit may then be closed and the first obstruction operated to re-opened and allow another animal to enter the station.

Advantages provided by the present invention include: N3\Melbourne\Cases\Patent\4900-49999\P49169.AU.3\Specis\P49169.AU.3.doc 15/01/08 00 i) when an animal is in the station, the animal can Sbe prevented from backing out through the entrance of the station; and IDii) when the animal has exited the station, the exits are closed to prevent an animal from entering the station via the exits.

Although it is possible that the first and second detecting means may be in any form, it is preferred that the detecting means be in the form of photo-electric 00 10 sensor that emits an electromagnetic beam transversely across the entrance or the exits.

The term electromagnetic beam in this specification embraces both visible and non-visible electromagnetic radiation including infrared and ultraviolet light.

It is preferred that the photo-electric sensors be arranged so that the beam be transmitted between either: i) a sender unit and a receiver unit on opposite sides of the entrance or exits; or ii) a sender and receiver located on the same side of the of the entrance or exits and a reflector on the opposite side thereof.

When the beam emitted by the sensors has been broken by an animal walking through the beam and the beam is subsequently restored by the animal moving past the beam, the first and second detecting means sends a signal to a controller that operates the first and second moveable obstruction means.

According to one embodiment, it is preferred that two of the exits be oppositely disposed side exits that face each other and the second moveable obstruction means includes a pair of first gates, wherein one of the first gates is located at each exit of the station and defines a passageway between the gates for an animal so that in use, when one of the first gates is pivoted outwardly to open one of the exits the other gate can be pivoted inwardly in N \Melbourne\Cases\Patent\49000-49999\P49169.AU.3\Specie\P49169.AU.3.doc 15/01/08 00- 6 O parallel relationship such that the passageway between the Sgates directs the animal through the opened exit.

cIt is preferred that the first gates be IN interconnected by a linkage member such that pivotal movement of one of the first gates can cause pivotal IDmovement of the other first gate via the linkage member.

Accordingly, it is preferred that one of the first gates be pivoted inwardly and outwardly by a pneumatic or hydraulic piston and cylinder arrangement. The other 00 10 first gate can thus be driven inwardly and outwardly by Sthe interconnecting linkage member.

It is preferred that the linkage member have a base that extends between the first gate members and two legs that project downwardly from the base on opposite sides of the passageway defined between the first gate members.

It is preferred that the second detecting means emits an electromagnetic beam across the passageway so as to detect when an animal has past through the exit.

It is preferred that the second detecting means be mounted to the legs of the linkage member at a height suitable for directed when an animal has past through the passageway.

It is preferred that the linkage member be pivotally mounted to each of the first gates such that components of the second detecting members can continually face each other while the first gates are pivoted inwardly and outwardly.

It is preferred that the linkage member be located toward an end of the first gates opposite to the end at which the gates are pivotally mounted.

It is also preferred that the device include a pair of second gates, wherein one of the second gates is located on the outside of each of the first gates and is prevented from moving inwardly when the first gate moves inwardly, thereby preventing an animal from entering the N.\Melbourne\Cases\Patent\490OO-49999\P49169.AU.3\Specis\P49169.AU.3.doc 15/01/08 00 7 station via the exits when the first gate has been pivoted Sinwardly.

According to a alternative embodiment, it is IN preferred that station has two oppositely disposed side exits that face each other and the second obstruction means includes a pair of first gates whereby one of the first gates is located at each exit of the station.

It is even more preferred that each first gate may be pivoted inwardly and/or outwardly of the respective 00 10 exit to which it is associated to open the exit. In the Ssituation where one of the first gates is moved to open the exit, it is preferred that the other first gate be retained in a substantially closed position and wherein inward and/or outward movement of the first gate is represented by the first gate being pivoted toward the first gate retained in the closed position to away from the first gate being retained in a closed position respectively.

It is preferred that each first gate be driven inwardly and/or outwardly by an actuator.

It is preferred that the device also have a further exit and the second moveable obstruction means allows animals to exit from the station via the further exit when the two side exits are closed.

Although it is possible that the first moveable obstructions means may be in any form, it is preferred that the first moveable obstruction means include a pair of third gates that are aligned with each other to extend across the entrance of the station. According to an alternative embodiment it is preferred that the first moveable obstruction means be in the form of a single gate that extends laterally across the entrance of the station when in a closed position.

It is preferred that each third gate be driven by a pneumatic or hydraulic piston and cylinder arrangement.

A person skilled in the art of the present invention will appreciate that suitable control devices N.\Melbourne\Caea\Patent\49000-49999\P49169.AU.3\Specia\P49169.AU.3.doc 15/01/08 00 8 O and actuators including electric solenoid valves can be Sused to operate the first and second obstruction means when the first and second detecting means detect that an IDanimal has entered or exited the station.

According to the present invention there is also IDprovided a device in the form of a station for separating animals into two or more groups, the station capable of being used in association with animal corral or other live-stock holding equipment including vehicles for 00 010 transporting live-stock, the station including: a) an entrance through which animals can enter the station; b) a first moveable obstruction means that can be operated to selectively open and close the entrance of the station and thereby allow an animal to enter the station; c) two exits disposed on opposite sides of the station through which the animals can exit; d) a second moveable obstruction means that includes a pair of first gates, wherein one of the first gates is located at each exit of the station and defines a passageway between the gates for an animal so that in use, when one of the first gates is pivoted outwardly to open one of the exits the other gate can be pivoted inwardly in parallel relationship so as to direct the animal through the opened exit; and e) a pair of second gates, wherein one of the second gates is located on the outside of each of the first gates and is prevented from moving inwardly such that an animal is prevented from entering the station via the exits when the first gates are pivoted inwardly.

The second gates are also capable of moving outwardly in response to each first gate moving outwardly.

In use, the first gates can be pivoted in parallel relationship such that when one of the first gates is pivoted inwardly the other gate is pivoted outwardly to open an exit. In this situation, the second gate located at the exit that has been opened will be pivoted outwardly N.\Melbourne\Caaes\Patent\49000-49999\P49169.AU.3\Specis\P49169.AU.3.doc 15/01/08 00 9 Owith the first gate In order to prevent animals from Sentering the station via the opposite exit, (ie. the exit n at which the first gate been pivoted inwardly,) the second IN gate will maintain a closed position by not pivoting inwardly (or outwardly).

ICThe present invention as described in the two paragraphs immediately above may also include any one of the features described in the preceding paragraphs including first and second detecting means for detecting 00 10 when an animal has past through the entrance and exits of the station.

BRIEF DESCRIPTION OF THE DRAWINGS Two preferred embodiments of the present invention will now be described with reference to the accompanying drawings, of which: Figure 1 is a top view of a drafting gate assembly or station according to a first embodiment having an entrance and three exits, two of which are side exits and the third exit is a forward exit, the two side exits of the drafting gate are closed; Figure 2 is a top view of the drafting gate shown in Figure 1 in which one of the side exits is opened; Figure 3 is a top view of the drafting gate shown in Figure 2 in which the opposite side exit is opened; Figure 4 is a rear view of the drafting gate shown in Figure 1; Figure 5 is a rear view of the drafting gate shown in Figure 1 in which the exit to the right hand side is in the process of being opened; and Figure 6 is a top view of a drafting gate assembly or station according to a second embodiment having an entrance and two side exits for directing animals in separate areas.

N: \Mebourne\Cases\Patent\49000-49999\P49169.AU.3\Specis\P49169.AU.3.doc 15/01/08 00 10 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT SThe two embodiments shown in the Figures have a number of features that are the same or substantially the same, and as a matter of convenience the same features numerals have been used on both embodiments to identify the same or similar features.

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The drafting gate assembly shown in Figures 1 to comprises four vertical posts and three pairs of pivotally mounted gates that are supported in a working position 00 10 above the ground. As can be seen in Figures 1 and 2, the Sposts may be regarded as forming forward and rear pairs of posts identified by reference numerals 10 and 11 respectively.

The spacing between the posts of each pair of posts, for example posts 10a and 10b, defines the width of the assembly and the spacing between each pair of posts and 11 represents the length dimension of the assembly.

The width dimension of the assembly is selected such that it may be fitted to pre-existing raceways with only minimal alteration.

The fence lines identified by the reference numeral 12 in Figures 1 and 2 represent fences that define a raceway in an exiting stockyard, corral or other stock handling equipment.

The assembly is designed to enable animals passing through the raceway to be selectively diverted to exit the assembly through one of three exits. Specifically, the embodiment shown in Figures 1 to 5 comprises three exits, two of which are side exits and the other is a forward exit. An animal can pass through the forward exit in the direction of arrow A when the assembly is configured as shown in Figure 1.

The assembly comprises three pairs of gates, namely entrance gates 21, guiding gates 13 and return gates 18. The pair of guiding gates 13 comprises guide gates 13a and 13b that are pivotally mounted to the forward pair of posts 10 located at the entrance of the N\Melbourne\Cases\Paent\49000-49999\P49169.AU.3\Speci\P49169.AU.3.doc 15/01/08 11- 00 Sassembly. In use, one of the gates 13a, 13b is pivoted Sinwardly while the other gate is pivoted outwardly such that a passageway formed between the gates directs an IDanimal through one of the side exits in the direction of the arrows B and C in Figures 2 and 3 respectively. The gate pivoted inwardly prevents the animal from exiting the assembly via either the forward exit or the opposite side exit.

The guiding gates 13a and 13b are also 00 10 interconnected by a linkage member 14 that is pivotally Sconnected to each of the guiding gates 13 such that an air or water piston and cylinder arrangement 15 directly acting on one of the gates 13a moves the other guiding gate 13b. As can be seen in Figures 4 and 5, the linkage member 14 is in the form of an inverted U-shaped member having a base 16 and downwardly extending legs 17 that are positioned on opposite sides of the passageway between the gates 13a and 13b.

The second pair of the gates 18 comprises two return gates 18a and 18b that are also pivotally mounted to the forward posts and located on outside of the guiding gates 13. The return gates 18 are also sized to span the gap between the forward posts 10 and the rear posts 11 or a stop member 19 projecting therefrom. The stop member 19 is preferably a flexible cushion that allows an animal to free itself should it become jambed between the posts 11 and the gates 13 and 18.

As can be seen in Figures 2 and 3, when one of the guiding gates 13 is pivoted outwardly, the guiding gate 13 engages the return gate 18 and pivots the return gate 17 outwardly. When the cylinder arrangement 15 is operated to return the guide gate 13 to a central position to close the side exits (as shown in Figure a biasing spring moves the return gate 18 to a closed position.

Figures 2 and 3 also illustrate that when one of the guiding gates 13 is pivoted outwardly to open one of the side exits, the other guiding gate 18 is pivoted N\Melbourne\Caae\Patent\49000-49999\P49169.AU.3\Speci\P49169.AU.3.doc 15/01/08 00- 12- O inwardly to direct an animal through the side exit. The Scorresponding return gate 17, located at the outside of the guiding gate 13 that has been pivoted inwardly, IDremains in a closed position under the action of the biasing spring 20. For example, in the situation shown in SFigure 2 when the guiding gate 13a is pivoted outwardly and guiding gate 13b is pivoted inwardly, the return gate 18 associated with the guiding gate 13b is retained in the closed position, whereas the return gate 18 associated 00 10 with guiding gate 13a is opened outwardly.

C An advantage provided by the return gates 18 is that it provides a barrier against an animal entering the assembly via the side exits when each guiding gate 13a and 13b is pivoted inwardly.

The third pair of gates, identified by reference numeral 21, comprises two pivotally mounted entrance gates 21a and 21b that are aligned to extend laterally across the entrance of the assembly. Each entrance gate 21 includes an air or water driven cylinder and piston arrangement 22 for pivoting each gate.

The assembly also includes two detecting means, namely a first detecting means located at the entrance of the assembly that can detect when an animal enters the assembly. The detecting means may be in any suitable form including photo-electric sensors 23 that emits an infrared electromagnetic beam transversely across the entrance which is shown in Figures 1 to 3 by dashed line T.

The photo-electric sensor 23 may include a sender unit and a receiver unit that are mounted on the forward posts 10a and 10b so that a beam is transmitted across the entrance of the assembly. The photo-electric sensor may alternatively include a sender and receiver unit located on one post such as post 10a, and a reflector on the opposite post The second detecting means is the form of a photoelectric sensor 24 located on the linkage member 14 located approximately two thirds from the end at which the N.\Melbourne\Cases\Patent\49000-49999\P49169.AU.3\Specis\P49169.AU.3.doc 15/01/08 00- 13 C gates are pivotally mounted to the posts 10. The Selectromagnetic beam emitted by the sensor 24 is shown as a dashed line S in the Figures 4 and The linkage member is pivotally mounted to the guiding gates 13 such that the sensor 24 on the opposite IDsides of the passageway face each other regardless of the position of the guiding gates 13.

In use, when the photo-electric sensor 23 detects that an animal has past through the entrance of the 00 10 assembly, the entrance gates 21 can be closed to prevent an animal from exiting the assembly via the entrance, and in addition, prevent another animal from entering the assembly prior to the animal in the assembly exiting the assembly. The guiding gates 13 can then be operated to open and/or close the side exits so that the animal joins a desired group. When the photo-electric sensor 24 detects that the animal has past through the desired exit, the exit may then be closed and the entrance gates reopened to allow another animal to enter the assembly. At all stages during operation, the return gates 18 maintain a closed position unless pivoted outwardly by a guiding gate 13, thereby preventing an animal from entering the assembly via an exit.

Advantages provided by this arrangement include: i) when an animal is in the station, the animal can be prevented from backing out through the entrance of the station; ii) when the animal has exited the station, the exits are closed to prevent an animal from entering the station via the exits; and iii) when the one of the exits of the station have been opened, an animal is prevented from entering the assembly via the other exit.

The second embodiment of the present invention shown in Figure 6 provides essentially the same benefits and advantages of the embodiment shown in Figures 1 to In particular, the drafting gate assembly shown in Figure N\Melbourne\Caea\Patent\49000-49999\P49169.AU.3\SpeCiS\P49169.AU.3.doc 15/01/08 00- 14 O 6 enables animals passing through the drafting gate to be Sselectively diverted via one of two side exits in the ndirection of arrows B or C. The gate assembly comprises two pairs of pivotally mounted gates that are selectively opened and closed to allow animals to enter and leave the Sdrafting gate via a predetermined exit. Specifically, the entrance gates 21 are pivotally mounted on either side of the raceway defined by fence lines 12. When the entrance gates 21 are closed, the gates 21 are aligned across the 00 10 entrance of the raceway and obstruct animals from walking Salong the raceway and, when opened, the entrance gates 21 are stowed adjacent to the fence line 12 on each side of the raceway. Each entrance gate 21 is driven between opened and closed positions by actuators 22, preferably in the form of an air or water driven cylinder and piston arrangement.

The assembly also comprises two guiding gates 13a and 13b that are pivotally mounted to a rearward pair of posts 11 and a fixed end panel 26 that spans between the posts 11. The guiding gates 13a and 13b are each located at side exits of the raceway and are each driven between closed and open positions by actuators 15, preferably in the form of an air or water driven cylinder and piston arrangement. The assembly also includes two detecting means, namely a first detecting means preferably in the form of a first photo-electric sensor 23 that is also located forwardly of the entrance gates 21 (in the direction of travel of the animals along the raceway) and a second detecting means, also preferably in the form of a photo-electric sensor 24. The second photo-electric sensor 24 is located forwardly of the first photo-electric sensor and rearwardly of the guiding gates 13a and 13b.

The photo-electric sensor 23 and 24 form a beam across the raceway which are broken when an animal passes through the beam and which is restored when the animal moves past the sensors 23 and 24. The space between the sensors 23 and 24 in effect provides a holding region in which an animal N\elbourne\Cases\Patent\49000-49999\P49169.AU.3\SpeCiB\P49169.AU.3.doc 15/01/08 00- 15 C can be located while the identity of the animal is Sverified and allows the desired guiding gate 13a or 13b to be opened inwardly without obstruction by the animal. If IN necessary, in the situation where the sensor 24 detects that the beam has been broken by an animal approaching the IDend panel 26 before one of the guiding gates 13a or 13b has been opened, the guiding gates 13a and 13b can be retained in a closed position until the beam across sensor 24 has been re-established, indicting that the animal has 00 10 retreated into the holding region between the sensors 23 Sand 24.

Ideally operation of the embodiment shown in Figure 6 is substantially the same as the operation of the embodiment in Figures 1 to 5. Specifically, prior to an animal entering the assembly, each of the guiding gates 13a and 13b are located in a closed position substantially parallel to the fence line 12 and the entrance gates 21 are located in an open position substantially parallel to the fence line 12. When the photo-electric sensor 23 detects that an animal has past through the entrance of the assembly the beam was initially broken and subsequently restored, the entrance gates 21 are moved into a closed position as shown in Figure 6 to prevent the animal from exiting the assembly via the entrance. Upon a determination being made as to which of the two exits the animal should leave the assembly, one of the actuators is operated to open one of the guiding gates 13a and 13b of the respective side exit. For example, in the situation where it is desired to direct an animal to the left of the raceway, in the direction of arrow C, guiding gate 13b will be moved inwardly across the raceway (as shown by the broken lines) to direct the animal through the exit defined between posts 10b and lib while guiding gate 13a is retained in a closed position. Conversely, in the situation where it is desired to direct an animal to the right of the raceway in the direction of arrow B, guiding gate 13a will be moved inwardly across the raceway N\Meborne\Caeea\Paaent\4900-49999\P49169.AU.3\Specia\P49169.AU.3.doc 15/01/06 16 (as shown by the broken lines) to direct the animal Sthrough the exit defined between posts 10a and 10b while Sguiding gate 13b is retained in a closed position.

Although not shown in Figure 6, it is also possible for the guiding gates 13a and 13b to be opened Ioutwardly away from the raceway to allow the animal to leave the assembly from the desired exit.

With respect to either of the two embodiments mentioned above, the task of determining which exit of the 00 10 assembly the animal should be directed through can be achieved using any suitable means. For example, in the situation where the farmer has a small herd of the animals and can recognise individual animals, the farmer may make a decision on inspecting each animal and operating controls that operate the respective actuators to direct the animal through the assembly. In the situation where the number of animals is significantly greater, an automated technique for identifying animals that is currently available involves each animal being fitted with individual ear tags that emit a signal representing a number coding. A receiver is then located in close proximity to the assembly such that the signal received from the ear tag can be used to identify the particular animal that has entered the assembly. Once the identity of the animal is known, the animal can then be directed through the desired exit. The reliability of the automated system is dependant on the receiver receiving only one identification signal at a time. This can be achieved using standard techniques of shielding or prevent animals not in the assembly coming into close proximity of the receiver.

It will be appreciated by those skilled in the art of the present invention that many modifications and variations may be made to the preferred embodiments described above without departing from the spirit and scope of the invention.

N \Melborne\Caae8\Patent \49OOO-49999\P49169.AU.3\specie\P49169.AU.3.doc 15/01/08 00 17 Throughout this specification the terms herd or group have been used interchangeably and are intended to embrace the term mob.

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Claims (1)

18- 00 THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS: F1 1i. A stock drafting station for separating animals into two or more groups, the station capable of being used in association with animal corral or other live-stock o holding equipment including vehicles for transporting live-stock, the station including: a) an entrance through which animals can enter the station; 00 10 b) a first moveable obstruction means that is Soperable to selectively open and close the entrance of the station and thereby allow an animal to enter the station; c) two or more exits through which animals can exit the station, wherein two of the exits are in the form of opposite side exits that face each other; d) a pair of gates of which at least one gate is located at each respective exit and is operable to open and close the respective exit; and e) detecting means suitable for detecting either one or a combination of situations in which i) an animal has entered the station by passing through the entrance and/or ii) an animal has exited the station by passing through one of the exits. 2. The station according to claim i, wherein the detecting means comprises a first detecting means that detects when an animal has past through the entrance of the entrance of the station and in response to the first detecting means detecting an animal entering the station, the first obstruction means is closed to prevent an animal from exiting the station via the entrance. 3. The station according to claim 2, wherein the detecting means comprises a second detecting means that detects when an animal has past through, or is passing through, one of the respective exits, and in response to the detecting means detecting movement of an animal though Ns\Melbourne\Caaes\Patent\49000-49999\P49169.AU.3\Specis\P49169.AU.3.doc 15/01/08 00 19 the station, the gate of the respective exit is closed and Sthe first obstruction means is operated to re-open the entrance and allow another animal to enter the station. \O 4. The station according to claim 2 or 3, wherein the first and second detecting means are in the form of a photo-electric sensor that emits an electromagnetic beam Stransversely across the entrance and/or the exits. 00 5. The station according to any one of claims 1 to 4, wherein the first moveable obstruction means includes a pair of gates that are operable so that when in a closed position, the gates are aligned side-by-side to extend across the entrance of the station. N.\Melbourne\Caaee\Patent\49000-49999\P49169.AU.3\Specia\P49169.AU.3.doc 15/01/08