Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
199 words
A control system for remotely controlling at least one alternating current electric-mains-operated appliance, including: a controller having electronic switch means for superimposing a control signal on an alternating current mains supply by interrupting the mains supply for a period adjacent a zero crossing in one or more selected half-cycles of the mains supply and substantially less than the mains supply cycle period thereby to hold the mains supply voltage substantially at zero during said interruption; at least one receiver means for monitoring the mains supply and for controlling said electrical appliance said receiver having (A) interruption detector means including a full wave rectifier means for providing a full-wave rectified signal from said mains supply; voltage threshold detector means for receiving said full-wave rectified signal and producing an output whenever the voltage of said full-wave rectified signal is lower than a threshold voltage; and means for responding to the durations of said outputs from said voltage threshold detector means to produce an indication of the occurrence of a said interruption; and (b) means responsive to said indications of the occurrence of an interruption to produce outputs for controlling said electric appliance in accordance with the control signal from the controller.
Claim 2
Dependent Claim
199 words
A control system for remotely controlling at least one alternating current electric-mains-operated appliance, including: a controller having electronic switch means for superimposing a control signal on an alternating current mains supply by interrupting the mains supply for a period adjacent a zero crossing in one or more selected half-cycles of the mains supply and substantially less than the mains supply cycle period thereby to hold the mains supply voltage substantially at zero during said interruption; at least one receiver means for monitoring the mains supply and for controlling said electrical appliance said receiver having (A) interruption detector means including a full wave rectifier means for providing a full-wave rectified signal from said mains supply; voltage threshold detector means for receiving said full-wave rectified signal and producing an output whenever the voltage of said full-wave rectified signal is lower than a threshold voltage; and means for responding to the durations of said outputs from said voltage threshold detector means to produce an indication of the occurrence of a said interruption; and (b) means responsive to said indications of the occurrence of an interruption to produce outputs for controlling said electric appliance in accordance with the control signal from the controller.
Claim 3
Dependent Claim
238 words
A control system for remotely controlling one or more alternating current electric-mains-operated appliances, including: a controller having electronic switch means for superimposing a control signal on an alternating current mains supply by interrupting the mains supply for a period adjacent a zero crossing in one or more selected half-cycles of a group of half-cycles of the mains supply and substantially less than the mains supply cycle period thereby to hold the mains supply voltage substantially at zero during the or each said interruption for producing a control signal comprising a sequence of selected and non-selected half-cycles in said group, the particular sequence characterizing an individual control signal; at least one receiver means for monitoring the mains supply and for controlling the or each electrical appliance to which it is connected; said receiver having: (A) interruption detector means including a full wave rectifier means for providing a full-wave rectified signal from said mains supply; voltage threshold detector means for receiving said full-wave rectified signal and producing an output whenever the voltage of said full-wave rectified signal is lower than a threshold voltage; and means for responding to the duration of said outputs from said voltage threshold detector means to produce an indication of the occurrence of a said interruption; and (B) means responsive to said indication of the occurence of an interruption to produce outputs for controlling said electric appliance in accordance with the control signal from the controller.
Claim 4
Dependent Claim
238 words
A control system for remotely controlling one or more alternating current electric-mains-operated appliances, including: a controller having electronic switch means for superimposing a control signal on an alternating current mains supply by interrupting the mains supply for a period adjacent a zero crossing in one or more selected half-cycles of a group of half-cycles of the mains supply and substantially less than the mains supply cycle period thereby to hold the mains supply voltage substantially at zero during the or each said interruption for producing a control signal comprising a sequence of selected and non-selected half-cycles in said group, the particular sequence characterizing an individual control signal; at least one receiver means for monitoring the mains supply and for controlling the or each electrical appliance to which it is connected; said receiver having: (A) interruption detector means including a full wave rectifier means for providing a full-wave rectified signal from said mains supply; voltage threshold detector means for receiving said full-wave rectified signal and producing an output whenever the voltage of said full-wave rectified signal is lower than a threshold voltage; and means for responding to the duration of said outputs from said voltage threshold detector means to produce an indication of the occurrence of a said interruption; and (B) means responsive to said indication of the occurence of an interruption to produce outputs for controlling said electric appliance in accordance with the control signal from the controller.
Claim 5
Dependent Claim
118 words
A control system according to claim 2, wherein the controller includes: detector means for detecting when the mains supply phase is within a predetermined phase difference from a zero crossing; counter means for counting half-cycles or integral multiples of half-cycles of the mains supply: selector means connected to the counter means and the detector means for selecting particular half-cycles in a sequence dependent on the control operation and the appliance to be controlled and for producing a trigger signal to initiate an interruption in each selected half-cycle; and wherein the electronic switch means is a semiconductor switching device connected to receive and respond to the trigger signal to short-circuit the mains supply until the next occuring zero crossing.
Claim 6
Dependent Claim
30 words
A system according to claim 3, wherein the controller includes manually settable means representing various control operations and/or appliances in response to setting of which the said sequence is selected.
Claim 7
Dependent Claim
41 words
A control system according to any of claims 2, 3 or 4, further including clock means programmable to instruct the controller to signal to the or each receiver to perform a control operation on its associated appliance(s) at a particular time.
Claim 8
Dependent Claim
18 words
A control system according to claim 2, wherein said electronic switch means comprises a gate controlled semiconductor device.