GB2027573A - Animal scares - Google Patents

Abstract

Rodent repelling apparatus comprising at least one electrical coil 13 for connection to a source of alternating current, and a heat sensitive switch 20 forming a randomly operable spark generator connected in series with the coil to provide randomly timed pulse of electromagnetically induced energy. <IMAGE>

Description

SPECIFICATION Pest repelling apparatus This invention relates to apparatus for repelling pests such as rats and mice from a location.

According to the invention, there is provided apparatus for repelling pests such, as rodents from a location, comprising at least one electrical coil having terminals for connection to a source of alternating current, and a randomly operable spark generator connected in series with the coil to provide said location with randomly timed pulses of electromagnetically induced energy, said pulses being composed of widely differing frequencies.

An embodiment of the invention will now be described by way of example only with reference to the accompanying drawings, which is a diagrammatic side view of a rodent deterrent apparatus according to the present invention, with the front cover removed.

Referring to the drawing, the apparatus 10 includes a casing 1 2 in which is housed two electrical coils 1 3 mounted end-to-end on an elongate hollow core 14. At one end the core is secured to a top wall of the casing by two locknuts 16, the other end of the core extending through an aperture 17 in the bottom wall of the casing. The coils are electrically connected in series and via a 4 way connecting block 19 to terminals Land N for connecting to a source of alternating mains current.

A spark generator, in this embodiment, a heat sensitive electric switch 20 is embedded in the lower of the two coils and is electrically connected in series with the coils. The switch is preferably embedded near the peripheral surface of the coil and in use is operated by the heat generated by the coil. To cool the coils the core is conveniently provided with a series of holes 14a in the wall of the core and the front cover (not shown) of the casing is provided with louvres. Should the coils overheat, a heat fuse 22 connected in series with the coils, will blow. In the present embodiment the heat fuse is set to blow at approximately 760c and the switch 20 is set to open at coil temperatures exceeding say 500c.Since the rate of temperature increase of the coil windings will depend amongst other variables on ambient temperature the opening and closing of the switch 20 will follow a random pattern to provide randomly timed pulses of electromagnetically.induced energy, with the pulses being composed of widely differing frequencies from say 15 cycles per second to over 200 Mega cycles per second.

In use, the exposed end of the core 14 would be clamped to any suitable metal structure, at the location to be protected from rodents, for example metal piping, and I have found that the above mentioned random pulses of electromagnetic energy transmitted through the piping in the form of vibration and noise is extremely effectively in ridding the location of rodents. Additional couplings from the core to metal structures at the locations may be provided by stranded wires clamped both to the core and to the metal structures.

In use in an upright position as shown in the drawing, the lower coil is spaced from the bottom wall of the casing by an electrically insulating washer (not shown) and the upper coil is spaced from the lower coil by a metal spacer.

The above described apparatus is particularly effective in deterring rodents if the turns of the coils are wound in opposite directions and if the number of turns is different. In the present embodiment, the upper coil consists of 4280 turns of .020" copper wire and having a resistance of 60-65 ohms, and the lower coil consists of 3880 turns of .020" copper wire and having a resistance of 50 to 55 ohms.

During use of the above described apparatus, i have found that the pulses of electromagnetic energy can have a duration varying from 3 to 7 minutes with a pulse spacing of between 13 and 23 minutes.

1. Apparatus for repelling pests such as rodents from a location, comprising at least one electrical coil having terminals for connection to a source of alternating current, and a spark randomly operable generator connected in series with the coil to provide said location with randomly timed pulses of electromagnetically induced energy, said pulses being composed of widely differing frequencies.

2. The apparatus of claim 1, wherein the spark generator is a heat sensitive electrical switch.

3. The apparatus of claim 2, wherein the switch is embedded in the turns of the coil So that heat generated by the coil determines the operation of the switch.

4. The apparatus of claim 3, wherein the switch is embedded near the peripheral surface of the coil.

5. The apparatus of any one of the preceding claims wherein two coils are mounted in end-toend relationship and electrically connected in series but wound in opposite directions.

6. The apparatus of claim 5, wherein the coil windings have a different number of turns.

7. The apparatus of any one of the preceding claims, wherein the or each coil is mounted on a hollow tubular core.

8. The apparatus of claim 7 wherein the coil or coils are surrounded by a casing; wherein the core is secured at one end to the casing, and the other end protrudes through the other end of the casing, and wherein means are provided for clarnping the protruding end of the core to a metal structure at said location.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (8)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Pest repelling apparatus This invention relates to apparatus for repelling pests such as rats and mice from a location. According to the invention, there is provided apparatus for repelling pests such, as rodents from a location, comprising at least one electrical coil having terminals for connection to a source of alternating current, and a randomly operable spark generator connected in series with the coil to provide said location with randomly timed pulses of electromagnetically induced energy, said pulses being composed of widely differing frequencies. An embodiment of the invention will now be described by way of example only with reference to the accompanying drawings, which is a diagrammatic side view of a rodent deterrent apparatus according to the present invention, with the front cover removed. Referring to the drawing, the apparatus 10 includes a casing 1 2 in which is housed two electrical coils 1 3 mounted end-to-end on an elongate hollow core 14. At one end the core is secured to a top wall of the casing by two locknuts 16, the other end of the core extending through an aperture 17 in the bottom wall of the casing. The coils are electrically connected in series and via a 4 way connecting block 19 to terminals Land N for connecting to a source of alternating mains current. A spark generator, in this embodiment, a heat sensitive electric switch 20 is embedded in the lower of the two coils and is electrically connected in series with the coils. The switch is preferably embedded near the peripheral surface of the coil and in use is operated by the heat generated by the coil. To cool the coils the core is conveniently provided with a series of holes 14a in the wall of the core and the front cover (not shown) of the casing is provided with louvres. Should the coils overheat, a heat fuse 22 connected in series with the coils, will blow. In the present embodiment the heat fuse is set to blow at approximately 760c and the switch 20 is set to open at coil temperatures exceeding say 500c.Since the rate of temperature increase of the coil windings will depend amongst other variables on ambient temperature the opening and closing of the switch 20 will follow a random pattern to provide randomly timed pulses of electromagnetically.induced energy, with the pulses being composed of widely differing frequencies from say 15 cycles per second to over 200 Mega cycles per second. In use, the exposed end of the core 14 would be clamped to any suitable metal structure, at the location to be protected from rodents, for example metal piping, and I have found that the above mentioned random pulses of electromagnetic energy transmitted through the piping in the form of vibration and noise is extremely effectively in ridding the location of rodents. Additional couplings from the core to metal structures at the locations may be provided by stranded wires clamped both to the core and to the metal structures. In use in an upright position as shown in the drawing, the lower coil is spaced from the bottom wall of the casing by an electrically insulating washer (not shown) and the upper coil is spaced from the lower coil by a metal spacer. The above described apparatus is particularly effective in deterring rodents if the turns of the coils are wound in opposite directions and if the number of turns is different. In the present embodiment, the upper coil consists of 4280 turns of .020" copper wire and having a resistance of 60-65 ohms, and the lower coil consists of 3880 turns of .020" copper wire and having a resistance of 50 to 55 ohms. During use of the above described apparatus, i have found that the pulses of electromagnetic energy can have a duration varying from 3 to 7 minutes with a pulse spacing of between 13 and 23 minutes. CLAIMS

1. Apparatus for repelling pests such as rodents from a location, comprising at least one electrical coil having terminals for connection to a source of alternating current, and a spark randomly operable generator connected in series with the coil to provide said location with randomly timed pulses of electromagnetically induced energy, said pulses being composed of widely differing frequencies.

2. The apparatus of claim 1, wherein the spark generator is a heat sensitive electrical switch.

3. The apparatus of claim 2, wherein the switch is embedded in the turns of the coil So that heat generated by the coil determines the operation of the switch.

4. The apparatus of claim 3, wherein the switch is embedded near the peripheral surface of the coil.

5. The apparatus of any one of the preceding claims wherein two coils are mounted in end-toend relationship and electrically connected in series but wound in opposite directions.

6. The apparatus of claim 5, wherein the coil windings have a different number of turns.

7. The apparatus of any one of the preceding claims, wherein the or each coil is mounted on a hollow tubular core.

8. The apparatus of claim 7 wherein the coil or coils are surrounded by a casing; wherein the core is secured at one end to the casing, and the other end protrudes through the other end of the casing, and wherein means are provided for clarnping the protruding end of the core to a metal structure at said location.