Electronic thermostat
First Claim
1. A digitally-operated thermostat for controlling the operation of an associated temperature changing device to maintain the temperature of an object at a desired level, comprising:
- digital temperature signal generating means in heat exchanging relationship with said object for generating a temperature signal comprising a pattern of voltage levels representative of the temperature of said object in binary coded decimal form, digital reference signal generating means adapted to be operated to produce a reference signal comprising a pattern of voltage levels representative of said desired level in binary coded decimal form, and digital comparing means responsive to pattern differences between said patterns of voltage levels representing said object temperature and said desired temperature when said pattern difference represents a difference in only one direction with respect to said desired level for producing an operate signal to cause operation of said temperature changing device, said temperature signal generating means comprising a variable frequency oscillator, said oscillator having a temperature sensor adapted to be placed in heat exchanging relationship with the object for varying the frequency of said oscillator as a function of the temperature of said object, counting means connected to said oscillator for encoding the frequency of said oscillator as binary coded decimal signals to provide said temperature signals, and clock means for cyclically resetting and enabling said counting means for a preselected interval of time in each cycle.
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Accused Products
Abstract
An electronic thermostat for controlling the operation of a temperature changing device such as a heater or a cooling device to maintain the temperature of an object at a desired level. The thermostat comprises a device in heat exchanging relationship with the object for generating a temperature signal representative of the temperature of the object. A reference signal generator is operable to generate a reference signal representative of the desired temperature level. A comparator compares the reference and temperature signals and produces an operate signal to operate the temperature changing device when the reference and temperature signals are unequal.
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Citations
11 Claims
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1. A digitally-operated thermostat for controlling the operation of an associated temperature changing device to maintain the temperature of an object at a desired level, comprising:
- digital temperature signal generating means in heat exchanging relationship with said object for generating a temperature signal comprising a pattern of voltage levels representative of the temperature of said object in binary coded decimal form, digital reference signal generating means adapted to be operated to produce a reference signal comprising a pattern of voltage levels representative of said desired level in binary coded decimal form, and digital comparing means responsive to pattern differences between said patterns of voltage levels representing said object temperature and said desired temperature when said pattern difference represents a difference in only one direction with respect to said desired level for producing an operate signal to cause operation of said temperature changing device, said temperature signal generating means comprising a variable frequency oscillator, said oscillator having a temperature sensor adapted to be placed in heat exchanging relationship with the object for varying the frequency of said oscillator as a function of the temperature of said object, counting means connected to said oscillator for encoding the frequency of said oscillator as binary coded decimal signals to provide said temperature signals, and clock means for cyclically resetting and enabling said counting means for a preselected interval of time in each cycle.
- View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
Specification