GB2260438A - Inspection system - Google Patents

Abstract

An inspection system comprises a control station (25), at least one key station (10) and a portable recorder (15), comprising timer means (19) and a memory means (20). The or each key station (10) and the portable recorder (25) have interactive inductive coupling means (12, 22) whereby identity information of the key station (10) is readable by the portable recorder (15) for storage in the memory means (20) thereof along with time information from the timer means (19), and the portable recorder (15) and the control station (25) comprises means (22, 26) to enable the identity and time information in the memory means (20) of the portable recorder (15) to be read by the control station (25). <IMAGE>

Description

Description of Invention This invention relates to an inspection system, particularly, but not exclusively, for application as a security system of a similar type to that disclosed in prior Patent No. GB 2141856.

In our prior Patent a security system is disclosed which comprises a plurality of key stations and a portable recorder or clock, the portable recorder and key stations having co-operating pin contacts which need to be brought into physical contact with one another to enable information to be passed from the key stations to the portable recorder.

Two problems have been found with the prior system namely in the reliability of the contacts, and in the physical size of the key station.

It will be appreciated that particularly where the key stations are exposed to the elements, it is difficult to keep the contacts of the key stations clean. Also, the connector pads of the key stations have to be at least as large as the connector pad of the portable recorder and simply reducing the size of such connector pads to enable the overall size of the key station to be reduced, would add to contact reliability problems.

According to one aspect of the invention we provide an inspection system comprising a control station, at least one key station, and a portable recorder, the portable recorder comprising a timer means and a memory means, the or each key station and the portable recorder having interactive inductive coupling means whereby identity information of the key station is readable by the portable recorder for storage in the memory means thereof, along with time information from the timer means, the portable recorder and the control station comprising means to enable the identity and time information in the memory means of the portable recorder to be read by the control station.

Thus by virtue of the inductive coupling means between the portable recorder and the or each key station, the reliability problems of the contacts of the former security system of prior Patent GB 2141856, are overcome.

Furthermore, the overall size of the key station can be reduced to an absolute minimum.

The invention will now be described with reference to the accompanying drawing which is a schematic illustration of an inspection system in accordance with the invention.

Referring to the drawing, there is shown an inspection system for use as a security system. The system comprises a plurality of key stations 10, only one of which is shown, which key stations 10 are located along a route to be taken by a security guard during his patrol. The key stations 10 may be secured to walls of buildings, provided on posts, or mounted in any other manner around the security guard's patrol route.

Each key station 10 comprises a control circuit 11 in which is stored unique identity information about the key station 10, such as for example, a key station number. Each key station 10 further comprises an induction coil 12. The key stations 10 need have no power supply of their own, but the necessary power to enable the key stations 10 to communicate their unique identity information is induced in the windings of the coil 12 as hereinafter explained.

The key stations 10 can each be of a very small physical size, and have no exposed electrical contacts. Thus the key station 10 can be self contained within a weatherproof housing 13.

To aid the efficiency of the coil 12, the coil 12 may be wound onto a ferrite former 14.

The system further comprises a portable recorder 15 which is carried by the security guard on his patrol. The portable recorder 15 has its own power supply, namely a battery 16, which may be replaced by opening a casing 17 or a part of the casing 17.

The portable recorder 15 comprises a controller 18, conveniently provided as a microprocessor, a real time clock 19 and a memory 20, all provided on a common circuit board 21. An induction coil 22, preferably wound on a ferrite former 23, is also connected to the board 21, along with an interlock 24 which is actuated when the casing 17 is opened, for a purpose hereinafter explained.

The system further comprises a control station 25 which conveniently comprises a personal computer, the personal computer having an adaptor either internally as shown, or connected to it externally, the adaptor comprising an induction coil 26 wound on a ferrite former 27, and a decoder 28.

Operation of the system will now be described.

A security guard collects his portable recorder 15 and sets out on his patrol. As the security guard passes each key station 10, he bring the portable recorder 15 into close proximity to the key station 10. The induction coil 22 is energised by the control circuit 18 in the portable recorder 15, and thus a signal is transmitted which is induced in the coil 12 of the key station 10. The induced signal provides sufficient power to the key station 10 for the control circuit of the key station 10 to modulate its power absorption according to a control characteristic which is dependent upon the unique identity information.

This modulation is detected by the portable recorder 15 as a change in loading seen by the control circuit 18 of the portable recorder 15 which is able to decode this modulation for example by detecting a resultant variation in frequency of the driving oscillator and hence derive the unique identity information of each key station 12.

Thus, by changing its input impedance during transmission in a manner according to the identity information, the amount of energy consumed by the portable recorder during transmission is varied in accordance with the modulated input impedance of the key station.

Alternatively, the control circuit 18 of the portable recorder 15 decodes this information by measuring the variation in voltage or current induced in a third coil placed within the alternating magnetic field linking the clock coil 22 and the key station coil 14. Other arrangements are possible.

In each case, this unique identity information for each of the key stations 12 visited by the security guard on his patrol, is stored in the memory 20 correlated with time information provided by the real time clock 19 at which each of the key stations were visited.

When the security guard returns to base, having completed his patrol route, the information contained in the memory 20 of the portable recorder 15 is downloaded into the computer 25. This is achieved by an inductive coupling between coil 22 of the portable recorder and coil 27 of the adaptor of the computer. The control circuit 18 of the portable recorder 15 may transmit a signal via the coil 22 which is amplitude modulated so as to transmit the information from memory 20 and the decoder 28 of the adaptor of the control station 25 decodes the signal received by the coil 27 io decipher the information contained in the signal.

The control station 25 may be programmed to provide a printout when required of the information transmitted to it, so that a check can be made that the security guard has in fact visited all the key stations 10 when he was supposed to. Alternatively or additionally, the control station 25 may transmit this information to a remote location. The control station 25 may be programmed to provide an alarm signal in the event that a security guard does not return to base by an allotted time.

In the event that the casing 17 of the portable recorder 15 is opened, the interlock 24 will cause a signal to be generated which is stored in the memory 20, to provide an indication that the casing 17 has been tampered with. If desired, this information may be correlated with the time the casing 17 was opened, as indicated by the real time clock 19. Thus any tampering with the portable recorder 15 by the security guard for example, can be determined when the content of memory 20 is downloaded into the control station 25.

Various refinements are possible to the basic system described. For example, the portable recorder 15 may provide an indication to the security guard that information has successfully been received from a key station 10. This may simply be achieved by a light emitting diode 30 flashing and/or a noise such as a bleep being generated by the portable recorder 15. Alternatively, the portable recorder may have a display such as a liquid crystal display which displays an alpha numeric message to the security guard that identity information has successfully been received from the key station 10.

In this latter case, the portable recorder 15 may be software configured so that the display indicates to the security guard which key station 10 is next on his patrol route such that a key station 10 is communicated with out of turn. In the event that the security guard does not follow his prescribed route, the portable recorder 15 may display an appropriate message to the security guard.

The route which is software configured into the portable recorder 15, may be a standard route, or the portable recorder may be software configured with a unique random route which the security guard must follow.

The portable recorder 15 may include a key pad to enable the security guard to enter information into the memory 20. For example, if the security guard notices an open window, he may enter an appropriate code for this incident into the portable recorder 15 by the key pad. This information may be correlated with the time from the real time clock 19. Downloading of the memory 20 at the control station 25 may prompt appropriate action to be taken. For example, a controller in charge of the control station 25 may alert an appropriate person to the open window.

The security guard may enter different codes into the portable recorder 15 via the key pad, for different incidents. The portable recorder 15 may have an active state in which information can be received from the key stations 10 and transmitted to the control station 25 via the inductive couplings and the key pad, where provided, and an inactive state when minimum power is consumed.

The portable recorder 15 may be switched to an active state by any desired means such as for example, a security guard operable switch provided on the portable recorder 15, or a switch automatically operated when the portable recorder is withdrawn from a holster in which it is carried.

Preferably though, the key stations 10 each have a magnet as indicated at 31, and the portable recorder 15 a reed switch so that as the portable recorder 15 is brought into close proximity with the key pad 10, the reed switch 32 is activated by the magnet 31 and the portable recorder 15 is thus switched to an active state. As the portable recorder 15 is moved away from the key station 10 after the identity information of the key station 10 has been transmitted by the inductive coupling to the portable recorder 15, the reed switch 32 may be deactivated by a spring means to return the portable recorder to an inactive state.

Various modifications are possible to the system described without departing from the scope of the invention.

If desired, the information may be downloaded from the memory 20 of the portable recorder 15 to the control station 25 by means of a physical connection such as a plug and socket connection, instead of the inductive coupling as described. Because the contacts of the control station are not exposed to the elements, this need not present any contact reliability problem.

The control station 25 need not comprise a personal computer although this is preferred as it enables a wide variety of processing to be carried out on the information downloaded from the portable recorder 15. Of course, each portable recorder 15 may carry its own identity information so that the control station 25 is able to distinguish between any one portable recorder 15 carried by one security guard, and any other portable recorder carried by another security guard, for example on a different patrol route. The personal computer of the control station 25 may thus be software programmed to handle the information from the portable recorders 15 as desired.

Although the invention has been devised for specific application to a security patrol system, it will be appreciated that the system described may have other applications.

For example, where it is desired to prove that a regular inspection has been made of, for example, an apparatus such as a valve, a key station may be provided adjacent the valve and an inspector may carry the portable recorder 15.

The identity information of the key station may be supplemented by status information about the valve. For example, when the valve is in an off position, the key station may be arranged to generate an appropriate signal along with the identity information, and if the valve is in an on position the key station may generate a different appropriate signal with the identity information. Thus the key station and valve may interact.

The features disclosed in the foregoing description, the following claims or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, or a class or group of substances or compositions as appropriate, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims (20)

1. An inspection system comprising a control station, at least one key station and a portable recorder, the portable recorder comprising timer means and a memory means, the or each key station and the portable recorder having interactive inductive coupling means whereby identity information of the key station is readable by the portable recorder for storage in the memory means thereof along with time information from the timer means, the portable recorder and the control station comprising means to enable the identity and time information in the memory means of the portable recorder to be read by the control station.

2. A system according to claim 1 wherein the or each key station has no associated power supply, but the key station is adapted to receive power from the portable recorder by induction when the portable recorder and key station are brought into sufficiently close proximity to one another.

3. A system according to claim 1 or claim 2 wherein the portable recorder is adapted to transmit a signal to the key station, the transmission by the portable recorder being modulated by the key station in a manner dependent upon the identity information, the portable recorder monitoring its own transmission and thereby reading the identity information of the key station.

4. A system according to claim 3 wherein the key station on receiving the signal transmitted from the portable recorder draws energy from the portable recorder according to a pre-programmed identity information characteristic, thereby modulating the amount of energy consumed by the portable recorder during transmission, a measure of the energy consumed by the portable recorder during transmission being monitored by the portable recorder whereby the portable recorder is able to determine the identity information of the key station.

5. A system according to claim 4 wherein the input impedance of the key stations varies according to a characteristic frequency modulation, the output impedance of the portable recorder varying in response, the portable recorder monitoring the varying output impedance to determine the unique identity information of the key station.

6. A system according to any one of claims 1 to 5 wherein the portable recorder comprises a casing with an interlock means between two casing parts, the interlock means providing a signal to the memory means of the portable recorder in the event that the two casing parts are separated from one another.

7. A system according to any one of claims 1 to 5 wherein a second inductive coupling means is provided between the portable recorder and the control station, to enable the information stored in the memory of the portable recorder to be read by the control station.

8. A system according to claim 7 wherein the portable recorder includes means to produce a signal amplitude modulated in dependence upon the nature of the information contained in the memory means of the portable recorder, the control station comprising decoding means to decode the amplitude modulated signal received thereby, to decipher the information from the memory means of the portable recorder.

9. A system according to any one of the preceding claims wherein a plurality of key stations are provided, each key station containing identity information unique to that key station, the portable recorder being interactive with each of the key stations to receive the identity information and to store information from each of the key stations in the memory of the portable recorder along with time information from the timer means, the portable recorder including means to discriminate information received from any one key station from information received from another key station and to provide a thus discriminated signal to the control station.

10. A system according to any one of the preceding claims which includes a plurality of portable recorders, each portable recorder comprising unique identity information which may be provided to the control station when the control station reads the information from the memory means of the portable recorder.

11. A system according to any one of the preceding claims wherein the portable recorder is normally in a deactivated state, the portable recorder being switched to an active state when the portable recorder and key station are brought into close proximity to one another.

12. A system according to claim 11 wherein the key station includes a magnet and the portable recorder a reed switch, the reed switch being actuated when the portable recorder and key station are brought into sufficiently close proximity to one another, the reed switch thus switching the portable recorder from a deactivated to an activated state.

13. A system according to any one of the preceding claims wherein the portable recorder includes means to indicate to a user that information has successfully been received from a key station.

14. A system according to claim 13 wherein the portable recorder includes a display means to enable an alpha numeric message to be displayed.

15. A system according to claim 14 wherein the portable recorder is software configured so that the display indicates to a user which key station the user is to visit next.

16. A system according to any one of the preceding claims wherein the portable recorder includes means to enable information to be fed into the memory means of the portable recorder, by an operator.

17. A system according to claim 16 wherein the means which enable the information to be fed into the memory means of the portable recorder comprises a key pad.

18. A system according to any one of the preceding claims wherein the key station is interactive with an apparatus or machine, the key station transmitting to the portable recorder status information about the apparatus or machine along with its identity information.

19. An inspection system substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

20. Any novel feature or novel combination of features herein defined and/or shown in the accompanying drawing.