Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
147 words
A security system for confining the use of equipment to an authorised user or users, wherein the system comprises: (i) at least one portable device to be worn or carried by a respective authorised user, the device having means for storing a respective unique digital identification code, means for transmitting the code in a predetermined format, and, coupled to an output of said transmitting means, an exposed conductive portion arranged, when in use, to be in contact with the user's skin; and (ii) a control unit to be coupled to the said equipment, the unit comprising means, having an electrical contact surface for receiving the transmitted code when the user touches said contact surface, means for comparing the code with an internally stored access code, and means for enabling said equipment only when said comparing means detects a match between the transmitted code and the access code.
Claim 2
Dependent Claim
147 words
A security system for confining the use of equipment to an authorised user or users, wherein the system comprises: (i) at least one portable device to be worn or carried by a respective authorised user, the device having means for storing a respective unique digital identification code, means for transmitting the code in a predetermined format, and, coupled to an output of said transmitting means, an exposed conductive portion arranged, when in use, to be in contact with the user's skin; and (ii) a control unit to be coupled to the said equipment, the unit comprising means, having an electrical contact surface for receiving the transmitted code when the user touches said contact surface, means for comparing the code with an internally stored access code, and means for enabling said equipment only when said comparing means detects a match between the transmitted code and the access code.
Claim 3
Dependent Claim
17 words
A security system according to claim 1, wherein said trigger means include a touch sensitive electrical switch.
Claim 4
Dependent Claim
168 words
A security system for confining the use of equipment to authorised users, wherein the system comprises: (i) at least one portable device to be worn or carried by a respective authorised user, the device having a store for storing a respective unique digital identification code, a transmitter for transmitting the code in a predetermined format, and, coupled to the output of the transmitter, an exposed conductive portion arranged to be in contact with the user's skin; (ii) a control unit to be coupled to the said equipment, the unit comprising an electrically conductive touch surface operable to receive the transmitted code from the portable device by electrical conduction through the user's body when the user touches the touch plate or surface, detection circuitry coupled to the plate or surface for comparing the transmitted code with a stored access code and for producing an output signal when the transmitted code matches the access code, and a security circuit for enabling the said equipment in response to the output signal.
Claim 5
Dependent Claim
168 words
A security system for confining the use of equipment to authorised users, wherein the system comprises: (i) at least one portable device to be worn or carried by a respective authorised user, the device having a store for storing a respective unique digital identification code, a transmitter for transmitting the code in a predetermined format, and, coupled to the output of the transmitter, an exposed conductive portion arranged to be in contact with the user's skin; (ii) a control unit to be coupled to the said equipment, the unit comprising an electrically conductive touch surface operable to receive the transmitted code from the portable device by electrical conduction through the user's body when the user touches the touch plate or surface, detection circuitry coupled to the plate or surface for comparing the transmitted code with a stored access code and for producing an output signal when the transmitted code matches the access code, and a security circuit for enabling the said equipment in response to the output signal.
Claim 6
Dependent Claim
22 words
A security system according to claim 3, wherein the touch surface forms part of a switching device for activating the detection circuitry.
Claim 7
Dependent Claim
15 words
A security system according to claim 4, wherein the switching device is a mechanical switch.
Claim 8
Dependent Claim
17 words
A security system according to claim 4, wherein the switching device is a touch sensitive electronic switch.
Claim 9
Dependent Claim
68 words
A security system according to claim 3, wherein said at least one portable device comprises a reference oscillator and a frequency divider, a memory for storing the said identification code, a digital serial encoder having a carrier signal input connected to an output of the frequency divider and a code input for receiving the identification code in serial form and an output coupled to the said conductive portion.
Claim 10
Dependent Claim
24 words
A security system according to claim 7, wherein the encoder comprises an MOS integrated circuit having its output connected directly to the conductive portion.
Claim 11
Dependent Claim
44 words
A security system according to claim 3 wherein said transmitting means includes a signal output and a reference output, and wherein said at least one portable device has two exposed electrically conductive portions connected, respectively to the signal output and to the reference output.
Claim 12
Dependent Claim
29 words
A security system according to claim 3, wherein the identification code is transmitted as a pulse-position-modulated signal having a carrier frequency in the range 10 kHz to 500 kHz.
Claim 13
Dependent Claim
34 words
A security system according to claim 1, wherein said control unit includes trigger means, actuable by the user to put the control unit in an enabled condition for receiving and comparing the transmitted code.
Claim 14
Dependent Claim
40 words
A security system according to claim 1, wherein said transmitting means includes first and second outputs, and wherein said at least one portable device has first and second exposed electrically conductive portions coupled to said first and second outputs, respectively.
Claim 15
Dependent Claim
138 words
An access control system comprising: (i) a portable device to be worn or carried by an authorised user of the system, the device having a store for storing a respective identification code, a transmitter for transmitting the code in a predetermined format, and, coupled to an output of the transmitter, an exposed electrically conductive portion arranged to be in contact with the user's skin; and (ii) An authorised user detector comprising a receiver having an electrically conductive input element arranged for electrical connection to the user's skin when in use whereby the transmitted code is received at the receiver by electrical conduction in the user's body, and comparison circuitry coupled to the receiver for comparing the transmitted code with a stored access code and for producing an access enabling signal when the transmitted code matches the access code.
Claim 16
Dependent Claim
138 words
An access control system comprising: (i) a portable device to be worn or carried by an authorised user of the system, the device having a store for storing a respective identification code, a transmitter for transmitting the code in a predetermined format, and, coupled to an output of the transmitter, an exposed electrically conductive portion arranged to be in contact with the user's skin; and (ii) An authorised user detector comprising a receiver having an electrically conductive input element arranged for electrical connection to the user's skin when in use whereby the transmitted code is received at the receiver by electrical conduction in the user's body, and comparison circuitry coupled to the receiver for comparing the transmitted code with a stored access code and for producing an access enabling signal when the transmitted code matches the access code.
Claim 17
Dependent Claim
14 words
A system according to claim 13 including receiver disabling means coupled to the receiver.
Claim 18
Dependent Claim
16 words
A system according to claim 14, wherein the disabling means comprises a touch sensitive switch device.
Claim 19
Dependent Claim
36 words
A system according to claim 13, wherein the transmitter has first and second outputs, and wherein the portable device has first and second exposed electrically conductive portions coupled to the said first and second outputs, respectively.
Claim 20
Dependent Claim
22 words
A system according to claim 13, wherein the portable device includes power conservation means for energizing the transmitter for a limited period.
Claim 21
Dependent Claim
26 words
A system according to claim 1, wherein said at least one portable device includes power conservation means for energizing said transmitting means for a limited period.