Patent ID: 6178572
Filing Date: 2001-01-30
Classification: E03C,F16K,Y10S

Abstract:
A control system for automatically controlling operation of a flow control bi-stable valve and for automatically preventing operation of the flow control valve under low battery voltage conditions, said control system comprising in combination:(a) a battery for supplying power to the bi-stable valve;(b) a passive detector for producing a detection signal in response to the presence of an object of interest in a predetermined region;(c) a first power driver circuit having a control input and an output capable of being coupled to the bi-stable valve to provide power to the bi-stable valve for opening the bi-stable valve;(d) a second power driver circuit having a control input and an output capable of being coupled to the bi-stable valve to provide power to the bi-stable valve for closing the bi-stable valve;(e) an alarm device for generating an alarm signal in the immediate vicinity of said control system;(f) a third circuit having a control input for producing a warning signal to energize said alarm device only once upon the presence of the object of interest in the predetermined region for a predetermined period in the range of about 1 to about 60 seconds and having an output coupled to said alarm device;(g) control circuitry enabled by the detection signal produced by said passive detector and having an input, said control circuit being adapted toi. produce a first control signal on the control input of said first power driver circuit in response to the detection signal if the voltage of said battery equals or exceeds a first determined threshold voltage and to enable said first power driver circuit to provide power to the bi-stable valve to cause opening of the bi-stable valve; andii. produce a second control signal on the control input of said second power driver circuit after the bi-stable valve has been opened to enable said second power driver circuit to provide power to the bi-stable valve to cause closing of the bi-stable valve;(h) a battery testing circuit enabled by the detection signal produced by said passive detector and indicative of the presence of an object of interest in the predetermined region, said battery testing circuit being adapted to:i. compare the voltage of said battery to the first predetermined threshold voltage and to a second predetermined threshold voltage greater than the first predetermined threshold voltage;ii. produce a third control signal on the input of said control circuitry to cause said control circuitry to produce the first control signal if the voltage of said battery is greater than or equal to the first predetermined threshold voltage;iii. produce a fourth control signal if the voltage of said battery is below the second predetermined threshold voltage and to apply the fourth control signal to the control input of said third circuit to produce on its output the warning signal to repeatedly energize said alarm device to produce a plurality of alarm signals for each predetermined period while the object of interest is present within the predetermined region and indicative of a low charge condition of said battery; andiv. produce a fifth control signal if the voltage of said battery is below the first predetermined threshold voltage and apply the fifth control signal to cause the bi-stable valve to be maintained closed until said battery is replaced.