Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
206 words
In an alarm timepiece comprising a timepiece movement; acoustic generating means mounted on said movement for generating an acoustic alarm signal; an electronic drive circuit mounted on said movement and having a detachable battery for providing current to said drive circuit; at least one alarm switch operatively connected with said movement and said drive circuit so that upon closure of same at a preset time said current flows through said drive circuit to initiate operation of same and cause said generating means to generate the acoustic alarm signal, the improvement wherein said generating means comprises a piezoelectric oscillator attached to a vibratable membrane mounted in said timepiece, said electronic drive circuit comprises a free-running oscillator circuit having an oscillator transistor; a switching transistor operatively connected to said oscillator transistor; a time limiting circuit operatively connected to said switching transistor, said time limiting circuit having a timer transistor and a resistor and condenser providing a time constant, so that when said alarm switch is closed said acoustic generating means emits the acoustic alarm signal for a time period determined by said time constant, and the time period of the acoustic alarm signal is limited to a small fraction of the total closure period of the alarm switch.
Claim 2
Dependent Claim
206 words
In an alarm timepiece comprising a timepiece movement; acoustic generating means mounted on said movement for generating an acoustic alarm signal; an electronic drive circuit mounted on said movement and having a detachable battery for providing current to said drive circuit; at least one alarm switch operatively connected with said movement and said drive circuit so that upon closure of same at a preset time said current flows through said drive circuit to initiate operation of same and cause said generating means to generate the acoustic alarm signal, the improvement wherein said generating means comprises a piezoelectric oscillator attached to a vibratable membrane mounted in said timepiece, said electronic drive circuit comprises a free-running oscillator circuit having an oscillator transistor; a switching transistor operatively connected to said oscillator transistor; a time limiting circuit operatively connected to said switching transistor, said time limiting circuit having a timer transistor and a resistor and condenser providing a time constant, so that when said alarm switch is closed said acoustic generating means emits the acoustic alarm signal for a time period determined by said time constant, and the time period of the acoustic alarm signal is limited to a small fraction of the total closure period of the alarm switch.
Claim 3
Dependent Claim
30 words
The alarm timepiece of claim 1, wherein said free-running oscillator circuit is connected directly to said battery, while said time-limiting circuit is connected through said alarm switch to said battery.
Claim 4
Dependent Claim
136 words
The alarm timepiece of claim 1, wherein said free-running oscillator circuit is of the Blocking type and connected between a capacitive element and a resistor element contained therein; the emitter electrode of said switching transistor, which is connected with said capacitative element, is connected through the primary winding of a transformer in said oscillator circuit, the secondary winding of which is at least partially connected operatively with said acoustic signal delivery means, with the base of the oscillator transistor, to thereby control said oscillator circuit with low current, and for interrupting the base current of said oscillator transistor substantially completely during the remaining closure period of the alarm switch which is devoid of the operational period of said acoustic signal delivery means so as to reduce the power consumption of the electronic alarm to a minimum.
Claim 5
Dependent Claim
65 words
The alarm timepiece of claim 1, wherein said free-running oscillator circuit is an astable multivibrator and said acoustic generating means is adapted for being driven by coil means inserted in said oscillator circuit, the base electrode of the oscillator transistor being electrically connected with the collector electrode of the switching transistor, so as to reduce the power consumption of the electronic alarm to a minimum.