Electric timepiece for displaying the operating condition thereof

Abstract

In a battery operated electric timepiece operated by a battery of the type including a time display, such as a second hand, when the voltage of the battery decreases below a predetermined value, the movement of the second hand is modified to give an alarm that the life of the battery has terminated.

What is claimed is: 
     
       1. In an electronic timepiece, which includes a battery means for producing a voltage of a predetermined level to drive a customary time display and associated circuitry for transmitting power at a predetermined frequency from the battery means to the customary display, wherein the associated circuitry includes: a reference signal souce for producing a divisible signal to drive the customary time display;   a counter for dividing the signal produced by the reference signal source, and for producing the signal of a predetermined frequency to drive said customary time display;   an auxiliary signal generator driven by the counter and having an output signal of a first frequency, different from the predetermined frequency;   a modulator including a frequency divider and a logic circuit, wherein said modulator has first and second inputs from the counter and an input from the auxiliary generator, wherein the first input from the counter is applied through the frequency divider, then to the logic circuit; wherein the second input from the counter is applied to the logic circuit; and wherein the input from the auxiliary signal generator is applied to the logic circuit; wherein the logic circuit generates a signal of a second frequency different from said first frequency;   detecting means for detecting, when the battery means produces a low voltage below said predetermined level, and for producing an alarm signal upon detecting said low voltage; and   signal transfer means activated in response to said alarm signal for selecting whether the signal having the predetermined frequency, or the signal having the second frequency will be applied to the display.   
     
     
       2. The electric timepiece of claim 1, wherein the signal transfer means includes an AND gate circuit, and wherein the alarm signal from the detecting means is a switching signal, which causes said transfer means to switch from said signal of the predetermined frequency to said signal of the second frequency. 
     
     
       3. The electric timepiece of claim 1, wherein the modulator generates repeating signals having a cycle, in which n pulses are produced within a time period having a duration of n seconds, wherein the n pulses occur during a first portion of each time period. 
     
     
       4. The electric timepiece of claim 2, wherein the modulator generates repeating signals having a cycle, in which n pulses are produced within a time period having a duration of n seconds, wherein the n pulses occur during a first portion of each time period. 
     
     
       5. The electric timepiece of claim 1, wherein the associate circuitry further includes an auxiliary counter, which receives signals from said counter and said detecting means, said auxiliary counter generating a third signal of a third frequency different from that of said modulator, and supplying the third signal to said signal transfer means to provide the signal transfer means with a third frequency for application to the signal transfer means. 
     
     
       6. The electronic timepiece of claim 1, wherein the logic circuit includes first and second AND gates, wherein the first AND gate has an input from the frequency divider, an input having the predetermined frequency from the counter and an output, which is the product of the inputs; and wherein the second AND gate has an input, which is the output of the first AND gate and an input, which is the output of said auxiliary signal generator, wherein the output of the second AND gate is the signal of the second frequency. .Iadd. 
     
     
       7.  An electronic timepiece powered by battery means, comprising: a source for producing a reference signal having a relatively high frequency;   means for dividing said reference signal to produce a relatively low frequency signal and a time unit signal of a predetermined frequency;   a display device having at least one hand adapted to display time;   a display actuator responsive to said time unit signal to produce a first drive signal of said predetermined frequency to actuate said display device in a customary mode;   a detector for detecting an output voltage of said battery means to generate a detection signal when said output voltage decreases below a predetermined level;   circuit means for generating a modulation signal of a second frequency different from said predetermined frequency in response to said relatively low frequency signal;   signal transfer means responsive to said detection signal for inhibiting said time unit signal being applied to said display actuator and for allowing said modulation signal to pass therethrough to said display actuator;   said display actuator being responsive to said modulation signal to produce a second drive signal of said second frequency whereby said hand is driven in a mode different from said customary mode to indicate an end of life of said battery means;   said display device further comprising a stepping motor which is driven by said display actuator; and   said circuit means comprising a modulator which is responsive to said relatively low frequency signal to produce said modulation signal. .Iaddend. .Iadd.   
     
     
       8.  An electronic timepiece of claim 7, wherein said circuit means also comprises an auxiliary signal generator having an input supplied with said relatively low frequency signal for producing an auxiliary signal, said modulator being responsive to said auxiliary signal to provide said modulation signal. .Iaddend. .Iadd. 
     
     
       9.  An electronic timepiece of claim 7, in which said circuit means comprises means for producing an additional modulation signal of a third frequency different from said second frequency, and further comprising means for generating an output signal at a predetermined time instant after said detection signal has been produced, said signal transfer means being responsive to said output signal to pass said additional modulation signal to said display actuator, whereby said display actuator actuates the hand of said display device in a second mode to indicate a second end of life of said battery means. .Iaddend.