GB2255113A - Silage silo barrier. - Google Patents

Abstract

There is provided a silage silo barrier which can be moved into various stable positions within the silo as feeding progresses and which contains, as part of the barrier, a front wire (10) or series of wires which are contacted by the cow's body during feeding but which are only electrified when the animal presses on the wires beyond a predetermined stage of tension. The barrier incorporates a tensioning switch (11) which determines whether or not the high tension supply will arc across two metal ring plates within the switch, and thus apply a shock to the cow. In the switch (Fig. 2. not shown), a spring loaded plastics tube (15) serves to space apart metal ring conductors (16), (17) connected to the generator and wire respectively. <IMAGE>

Description

ELECTRIFIED SILAGE SILO BARRIER This invention relates to a barrier,which can be electrified,for use in the selffeeding of cattle at the front face of a silage silo on a farm.

Barriers for restraining cattle feeding at the face of a silo are well known and many versions have been electrified but they all have the disadvantage that they are continuously on high tension so that the very high frequency of administration of shocks upsets the animals at a time when they should be content and placid.

In addition the continuous use of the high tension is a drain on the battery operated power system of the fence and attempts at switching the high volages are made very difficult because of the contact geometry required to prevent arcing and the dielectric strengths need in high humidity conditions.

There is a need therefore for a system which is not continuously electrified and which incorporates one,or more,wires which only come under high tension voltages when the animals advance too deeply into the set distances from the silage face.

According to the present invention there is provided an electrified silage silo barrier which comprises a metal frame which stably rests on the silo walls in any desired position at the front of the silage stack and which carries one or morse taut electrified wires,duly insulated,in such a switched position that the wires only carry high voltages when they are pressed by the cow's head or body movements.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 shows in front elevation the barrier resting upon the silo walls with its connections to the H.T.power source via the taut wire switch.

Figure 2 shows a front elevation section of the taut wire switch.

Referring to the drawings the electrified silage silo barrier comprises a metal gate 3 which rests with its horizontal crossbar 4 on top of the walls 2 which enclcse and contain the silage stack 1. When placed in the desired position at the front of the stack 1 the gate 3 is fixed in position between the walls 2 by means of a ruboer compression block 5 and a tightening screw clamp 6. In this position the metal up rights of the gate have fixed into them the clips 7 which terminate at one end in an electrical insulator 8. 3etween these insulators 8 is stretched a wIre lL,c,o,per or stainless steel,which is kept taut by the use of a wire tensioner 9 an isolated from the H.T.generator 13 and the co-axial lead 12 by means of the special tension switch 1 When the feeding animals proceed too deeply into the silage stack 1 its body pushes upon the wire lC but the wire is not put under high voltage until such times that the pushing action exceeds the arcing distances built into the switch but when his occur a shock is administered and the anjital withdraws a little. In a short time the herd soon learns how far they can penetrate the stack before the restraining shock is delivered. Up to the present the switching of high tension volatages of 8,0cho and above has been difficult and erratic in high moisture conditions such es those pertaining in an animal house orsilage feed clamp.Under difficult winter condition. the switch 11 of Figure 2 has proved to be very successful and comprises a cover 11 which receives the co-axial high tension cable 12 into a ring connection 16 which is set into a plastic(polyolefin or nylon) tube 14 which is welded or adhesively bonded to the cover 11. Within this tube 14, in a loose fitting syringe fashicn,is a moveable plastic tube 15 which carries another metal ring connector 17 to which is fixed the end of the taut wire 10. This wire 1C is tensioned by the use of the device 9 but this force is resisted by the action of the spring 18 thus allowing an equiliDrils to be established which determines the distance between the ring connectors 16 and 37.

When the animal pushes upon the wire 10 the spring 18 is put into further compression and the distance between the rings 16 and 17 decreases until,depending upon the humidity of the air, the system arcs and the resulting current flow puts the wire 10 under high tension voltage. As the animal withdraws a little from the silage stack 1 the spring 18 forces the plates 16 and 17 further apart and the arcing stops and the wire returns to earth potential. The switching device is simple,not elaborate,and is ideally suitable for handling high tension voltages in aggressive conditions.

Those skilled in the art will realize that other embodiments of the switching system are possible and that the apparatus can be employed in situations other than that of the silage stack face.

Claims (5)

1. An electrifiable silage silo barrier device,incorporating a tension switch, and comprising a stable but moveable frame which acts as a barrier to the front of the silage clamp but which incorporates a vire or series of wires which may or nay not be connected to a source of high voltage depending upon the tension which the animal exerts on the wires during feeding.

2. An electrifiable silage silo barrier device as in Claim 1 wherein the tension switch activates the wire or wires in the barrier gate through a variable arc gap formed between two ring connections within the body of the switch.

3. An electrifiable silage silo barrier device as in Claims 1 and 2 wherein the distance of the variable arc gap between the two ring connectors within the switch is determined by the applied tension in the barrier wire or wires by the animal's body movements during feeding.

4. An electrifiable silage silo barrier device as in Claim 1 wherein the tensions in the wire or wires in the gate are pre-determined before use by means of built-in electrically isolated wire tensioners.

5. An electrifiable silage silo barrier device as in Claim 1 vherein the gate of the barrier is rendered stable by the use of screw clamps and compression blocks which releasably wedge the barrier between the side retaining walls of the silage pit.

CLAIMS (continued) 6 An electrifiable silage silo barrier device according to any of the above Claims and substantially as described herein with reference to Figures 1 and 2 of the accompanying drawings.