INTRUDER DETECTION SYSTEM

Abstract: A method of and apparatus for detecting free-ranging pests, for example, mice, without providing an attractant material. The presence of a pest is sensed by at least one of a plurality of sensors, a signal is emitted indicating the sensing of a pest by that sensor, and the fact that a signal has been emitted is indicated by an indicating means that is operatively coupled to the sensors.

Description: Intruder Detection System The invention relates to a method and apparatus suitable for use in the control of free-ranging pests. The invention has particular relevance to the control of mice, but may also be useful in the control of other pests, for example, rats or cockroaches. In the past the control of free-ranging pests such as mice has normally involved placing bait, which may include poison, in places that the pests can be expected to frequent, the supply of bait being replenished from time to time. While replenishment of the bait may not cause problems in relatively small buildings, problems increase in large premises, for example, factories for processing food. Moreover, in both large and small premises it is in many circumstances necessary to take steps to ensure that the bait is not tampered with or swallowed by humans or other animals. The present invention is concerned primarily with alleviating problems that have arisen in connection with methods previously adopted for the control of pests such as mice. The present invention provides a method of detecting free-ranging pests without providing an attractant material in which method the presence of a pest is sensed by at least one of a plurality of sensors, a signal is emitted indicating the sensing of a pest by that sensor, and the fact that a signal has been emitted is indicated by an indicating means that is operatively coupled to the sensors. The invention also provides apparatus for detecting free-ranging pests which apparatus is free from means providing an attractant material and cαnprises a plurality of sensors for sensing the presence of a pest, each sensor having associated therewith means for signalling that a pest has been sensed by that sensor, and indicating means for indicating that a signal has been emitted, the indicating means being operatively coupled to the sensors. In accordance with the invention, the presence of a pest in the vicinity of one of the sensors will cause an indication of at least the first such event to be given by the indicating means. Where, as is preferred, the indicating means includes recording means, a record of at least the first such event, and preferably each subsequent event, will be made at the recording means. The indicating means may include, for example, a warning light so that it is easy to see when an event has taken place. Where the indicating means includes - 3 - both a warning light and recording means, the arrangement is preferably such that the warning light indicates that a pest has been detected by one of the sensors and that further inspection of the recording means is desirable. When the indicating means indicates that a pest has been detected, a decision can be taken as to whether a rodenticidal operation should be carried out. If, as is preferred, the indicating means is also capable of indicating which sensor(s) detected the pest(s), a particularly accurate placement of a rodenticidal preparation is possible. The fact that a rodenticidal operation, for example the placement of a preparation, need not take place until pests have been detected and, with the preferred apparatus, can be restricted to locations where mice or other pests are known to run, constitutes a significant improvement over previously proposed methods of pest control. It will be appreciated that with appropriate apparatus and sufficient sensors it will be possible to identify preferred runways followed by the pests in the premises in which the apparatus is installed, thus facilitating even further the correct placement of a rodenticidal preparation. As the method and apparatus of the invention do - 4 - not involve the use of an attractant material such as a food__stuff, the unnecessary introduction of extraneous materials into the areas to be protected is avoided. In accordance with the invention, however, means providing a relatively favoured environment for the pests may be provided in the vicinity of each sensor. The provision of a relatively favoured environment in the vicinity of the sensors may increase the likelihood of pests that are present in the location, for example, the building, in which the apparatus is installed, being detected by the apparatus. Where mice "are to be detected a relatively favoured environment may be provided by situating each sensor in a narrow channel, or in an enclosure, for example a box, which channel or enclosure is provided with holes through which the mice may enter or leave. We have observed that mice favour enclosed spaces, especially when these are small enough for the mice to contact opposed walls simultaneously. The use of enclosed spaces may also be advantageous in detecting other creatures having cryptic habits. Where a narrow channel is used to provide the relatively favoured environment the channel advantageously comprises one or more tubes running, for example, along the floor at the bottom of a wall, or up a wall, for example, in a corner. Such tubes are advantageously provided with holes at intervals along their length so that mice can enter the tubes. The tubes provide preferred runways for the mice. Sensors are so positioned that mice in the tubes can be detected. An advantageous enclosure is a small box containing the sensor, the box being provided with two holes through which a mouse can squeeze. In both the tube(s) and the __, box the holes (s) and sensor (s) are normally so arranged that sensors are not triggered by a finger or o.ther extraneous item inserted through a hole. Any suitable sensing means may be used in accordance with the invention. Possible sensors include those responsive to changes in pressure, temperature, smell, sound (including ultrasound) , and/or capacitance in the vicinity of the sensor. Transducers, especially pressure transducers, may of course be used. Other possibilities are the use of a microswitch which is activated when a mouse or other pest pushes past a wire, or any other device that is capable of responding when the pest brushes against it. Preferred sensors are those in which the pest interrupts a light beam, for example an infra-red beam. If desired such a beam may be deflected round corners using mirrors or light guides or pipes, and/or the beam could be positioned so that it is too high to be interrupted by, for example, a small insect crawling over the floor but is sufficiently low to be interrupted by, for example, a mouse. More generally, it may in some circumstances be advantageous if the sensors are such that they do not respond to the presence of bodies substantially larger or substantially smaller than the pests it is desired to detect. For example, where the apparatus is to be used to detect the presence of mice it will normally be advantageous for the sensors to be unresponsive to people on the one hand and insects on the other. In other circumstances, however, for example, if it is desired to detect the presence of all pests of or below a certain size, it will be advantageous for the senso rs to be responsive to all bodies of or below that size but unresponsive to bodies substantially above that size. In any given method or apparatus the sensors must of course be chosen having regard to the pests to be detected and the location in which the sensors are to be installed. The sensors should as far as possible be free from the risk of responding to extraneous events, for example, vibrations due to the operation of machinery nearby. Preferably the sensors merely sense the presence of the pests and the pests are unaffected by the system. The means for signalling that a pest has been detected by a sensor may be such that the same signal is produced by each sensor. If desired, however, each sensor, or group of sensors, may have a characteristic signal so that it is possible to identify more accurately the place where pests have been detected. This may be of particular advantage when the method and apparatus are used in very large premises. The signals emitted on sensing of a pest by a sensor are transmitted to an indicating means which is capable of indicating the occurrence, and advantageously the time and/or the location, of at least the first event that occurs after the apparatus has been set. As indicated above, the indicating means may .comprise recording means capable of recording the occurrence, and advantageously the time and/or the location of. at least the first event. Preferably the recording means is also capable of recording the occurrence, and advant¬ ageously the time and/or the location, of each sucessive event. If desired, each sensor can be individually linked to the indicating means, or signals from sensors in a group of sensors may be transmitted via a common link to the indicating means. Such a system, however, has the disadvantage that very great lengths of cable could be necessary in large premises, and it is relatively complicated and expensive to change the positions of the sensors. Moreover, where a common link is used, it may not be possible (depending on the type of signals used) to distinguish between the signals from different sensors. Advantageously, there is also provided means for transmitting the signal from signalling means associated with each sensor and means for receiving the transmitted signals and passing signals to the indicating means. Thus, for example, the apparatus may include means for transmitting the signals via the main electricity supply conductors and means for receiving the signals from these conductors. Where signals are transmitted via the mains it is necessary to take into consideration fluctuations that can occur in the mains voltage and to prevent spurious responses occurring as a result of them. An advantageous method of transmitting the signals involves the use of a radio transmitter associated with each sensor and one or more radio receivers. Preferably there is a common receiver for all the transmitters, the common receiver advantageously being in the vicinity of the indicating means. One advantage of the use of radio transmission is that the sensors can readily be moved from one location to another. Due regard must be had, however, to the surroundings in which the transmitter is to be used so that, for example, interference can be - 9 - eliminated or reduced and so that the operation of surrounding equipment is not adversely affected. A further advantageous method of transmitting the signals involves the use of infra-red light. Thus, for example, each sensor could be provided with means for transmitting infra-red light, there being one or more receivers for the infra-red light. If desired a common receiver could be used for two or more of the sensors. When the invention is to be used for detecting the presence of a pest that could adversely affect the operation of the apparatus, the apparatus preferably comprises means for indicating that the apparatus has been so affected. Thus, for example, where the apparatus is to be used for detecting mice the apparatus advantage¬ ously includes means for indicating that part of the apparatus has been rendered inoperative by the mice (by, for example, the mice nibbling through a wire) . The method and apparatus of the invention are suitable for detecting pests in premises of all sizes. It will be appreciated that for reliable detection over the entire premises sensors will be situated at a plurality of different locations in the premises. Where increased viligance is desirable in one particular area, for example, one particular room, a greater than average number of sensors may of course be located in that area. In very large premises it may in some cases be desirable to install more than one system according to the invention, that is to say there may be more than one indicating means, each indicating means having associated with it a plurality of sensors, but preferably there will be only one system according to the invention and thus a single indicating means for the entire premises, for example, a building in which pests are to be detected. Various forms of apparatus for detecting free- ranging pests constructed in accordance with the invention will now be described by way of example with reference to the accompanying drawing, the single figure of which is a block diagram. Referring to the drawing, one form of the apparatus comprises a plurality of sensors 1 each of which is provided with signalling means 2 and transmitting means 3 for the signal from the signalling means. An indicating means indicated generally by the reference numeral 4 is provided with means 5 for receiving the transmitted signals. The indicating means comprises a warning light 6 and recording means 7. - 11 - In use, when a pest 8 passes one of the sensors 18 the respective signalling means 2 emits a signal, which is transmitted by the respective transmitting means 3 to the receiving means 5. The receiving means 5 passes the signal to the indicating means 4, which illuminates the warning light 6, and records in the recording means 7 the fact that, and the time at which, the signal was emitted. If more than one signal is received, the warning light 6 is illuminated when the first signal is received and remains lit, while each signal is recorded in the recording means. Instead or in addition there may be a plurality of warning lamps ' 9 each associated with a respective sensor 1, and the indicating means then illuminates each lamp 9 if and when its respective sensor senses a pest. The recording means may record which signalling means 2 emitted each signal that it records. Instead, the sensors 1 may be divided into a plurality of groups 10, and the indicating means 4 may record and indicate the group of sensors, but not the individual sensor, by which each signal was emitted.

Claims: Cl aims 1. A method of detecting free-ranging pests without providing an attractant material in which method the presence of a pest is sensed by at least one of a plurality of sensors, a signal is emitted indicating the sensing of a pest by that sensor, and the fact that a signal has been emitted is indicated by an indicating means that is operatively coupled to the sensors. 2. A method as claimed in claim 1, wherein there are a plurality of groups of sensors, the number of sensors in each group being smaller than the total number of sensors, and the indicating means also indicates to which group of sensors the sensor that sensed the pest belongs. 3. A method as claimed in claim 1 or claim 2, wherein the indicating means also indicates which sensor sensed the presence of the pest. 4. A method as claimed in any one of claims 1 to 3, wherein the indicating means also indicates the time or approximate time at which the pest was sensed. 5. A method as claimed in any one of claims 1 to 4, wherein the indicating means comprises recording means and the fact that a signal has been emitted is recorded and indicated by the recording means. 6. A method as claimed in any one of claims 1 to 5, wherein the indicating means comprises at least one warning light. 7. A method as claimed in claim 5, wherein a number of pests are sensed and the indicating means comprises a warning light that is illuminated on sensing of the . first pest, and wherein the sensing of the first pest and the sensing of subsequent pests is recorded and indicating by the recording means. 8. A method as claimed in any one of claims 1 to 7, wherein each sensor has signalling means associated therewith and there is also provided means for transmitting signals from the signalling means and means for receiving the transmitted signals and passing the signals to the indicating means. 9. Apparatus for detecting free-ranging pests which apparatus is free from means providing an attractant material and comprises a plurality of sensors for sensing the presence of a pest, each sensor having associated therewith means for signalling that a pest has been sensed by that sensor, and indicating means for indicating that a signal has been emitted, the indicating means being operatively coupled to the sensors. 10. Apparatus as claimed in claim 9 which also comprises one or more features specified in any one of claims 2 to 8.

Inventors: MEEHAN ADRIAN PATRICK, MEEHAN, ADRIAN, PATRICK
Applicants: RENTOKIL LTD, RENTOKIL LIMITED
Application year: 1986
Main classification: A01M29
IPC codes: A01M1, A01M31, G08B21