Means for refreshing a triac control circuit power supply

• US 5,025,134 A
• Filed: 01/16/1990
• Issued: 06/18/1991
• Est. Priority Date: 05/24/1988
• Status: Expired due to Fees

• Current Assignee: David Bensoussan, Don Tardio
• Original Assignee: David Bensoussan, Don Tardio
• Inventors: Tardio, Don, Bensoussan, David
• Primary Examiner(s): Beha, Jr., William H.
• Application Number:
  US07/465,734
• Time in Patent Office: 518 Days
• Field of Search: 323/235, 323/239, 323/245, 323/319, 323/324, 323/236, 219/499, 219/501, 219/494, 307/647, 307/117, 307/132 T
• US Class Current: 219/494
• CPC Class Codes: G05D 23/1909 whose output amplitude can only take two discrete values
• CPC Class Codes: G05D 23/24 the sensing element having a resistance varying with temperature, e.g. a thermistor
• CPC Class Codes: H02M 1/0006 Arrangements for supplying an adequate voltage to the control circuit of converters
• CPC Class Codes: H02M 5/2573 with control circuit

Abstract

An electronic controller comprising two input terminals between which an AC line and an electrical load are connected in series. A processing unit generates a command signal to control the supply of electrical power to the electrical load which closes an electronic switch also connected between the two input terminals for connecting the AC line and the load in series in a closed loop. A power supply voltage of the controller is provided by a second power supply derived from the two input terminals, consequently from the AC line through the load when the switch is open. When the command signal is generated, an electronic circuit opens the switch which is normally closed by this command signal to maintain the power supply voltage of the controller according to an adequate standard of operation. To energize the controller, the opening of the switch is activated in a temporary and repetitive manner for a certain whole number of cycles of the sector. This opening is whether periodic or occurs while the power supply voltage of the controller transits underneath a predetermined threshold value.

Claims

1. An electronic controller for controlling a supply of an alternating electrical power issued from a first power supply to an electrical load, comprising:

(a) two input terminals between which said first power supply and said load can be connected in series;

(b) an electronic switch connected between said two input terminals;

(c) a second power supply for generating a power supply voltage for said electronic controller, said second power supply voltage being derived from said two input terminals and consequently from said first power supply through said electrical load when said switch is open, said second power supply being provided with means for storing electrical energy;

(d) voltage detecting means having inputs connected to said means for storing electrical energy, and an output for generating a positive output signal when voltage across said means for storing electrical energy is higher than a predetermined voltage value;

(e) a sensor for detecting a measurable physical parameter, and generating a positive output signal when said physical parameter is not within a range of predetermined values;

(f) a zero crossing detector for detecting voltage provided by said first power supply and generating a positive output signal when said voltage of said first power supply crosses zero volt; and

(g) means for generating a command signal to control said supply of electrical power to said electrical load, said means for generating having inputs connected respectively to outputs of said voltage detecting means, said sensor and said zero crossing detector, said command signal having a closing state which causes said electronic switch to close and connect said two input terminals by means of said switch only when said three positive output signals are received at said inputs of said means for generating, in such a manner that said first power supply is connected in series with said load in closed loop and thus supplies said electrical power to said load, said command signal further having a normally open state which causes said electronic switch to open for a whole number of power supply cycles from said first power supply so that said means for storing electrical energy of said second power supply is charged from said first power supply, said command signal being maintained in the open state as long as the three positive output signals are not generated.

2. An electronic controller according to claim 1, wherein said electrical load is a heating resistance and said physical parameter is temperature.

3. An electronic controller according to claim 2, wherein said electronic controller is a thermostat.

4. An electronic controller for controlling a supply of an alternating electrical power issued from a first power supply to an electrical load, comprising:

(a) two input terminals between which said first power supply and said load can be connected in series;

(b) an electronic switch connected between said two input terminals;

(c) a second power supply for generating a power supply voltage for said electronic controller, said second power supply voltage being derived from said two input terminals and consequently from said first power supply through said electrical load when said switch is open, said second power supply being provided with means for storing electrical energy;

(d) a sensor for detecting a measurable physical parameter, and generating a positive output signal when said physical parameter is not within a range of predetermined values;

(e) a zero crossing detector for detecting voltage provided by said first power supply and generating a positive output signal when said voltage of said first power supply crosses zero volt;

(f) a clock means having inputs connected to said first power supply, and an output for generating periodically a positive output signal having a time period defined by a whole number of cycles of said first power supply; and

(g) means for generating a command signal to control said supply of electrical power to said electrical load, said means for generating having inputs connected respectively to outputs of said clock means, said sensor and said zero crossing detector, said command signal having a closing state which causes said electronic switch to close and connect said two input terminals by means of said switch only when said three positive output signals are received at said inputs of said means for generating, in such a manner that said first power supply is connected in series with said load in closed loop and thus supplies said electrical power to said load, said command signal further having a normally open state which causes said electronic switch to open for a whole number of power supply cycles from said first power supply so that said means for storing electrical energy of said second power supply is charged from said first power supply, said command signal being maintained in the open state as long as the three positive output signals are not generated.

5. An electronic controller according to claim 4, wherein said electrical load is a heating resistance and said physical parameter is temperature.

6. An electronic controller according to claim 5, wherein said electronic controller is a thermostat.

7. Thermostat for controlling a supply of an alternating electrical power issued from a first power supply to a heating resistance, comprising:

(a) two input terminals between which said first power supply and said resistance can be connected in series;

(b) an electronic switch connected between said two input terminals;

(c) a second power supply for generating a power supply voltage for said thermostat, said second power supply voltage being derived from said two input terminals and consequently from said first power supply through said resistance when said switch is open, said second power supply being provided with means for storing electrical energy;

(d) voltage detecting means having inputs connected to said means for storing electrical energy, and an output for generating a positive output signal when voltage across said means for storing electrical energy is higher than a predetermined voltage value;

(e) a sensor for detecting ambient temperature, and generating a positive output signal when said temperature is lower than a predetermined temperature value;

(f) a zero crossing detector for detecting voltage provided by said first power supply and generating a positive output signal when said voltage of said first power supply crosses zero volt; and

(g) means for generating a command signal to control said supply of electrical power to said heating resistance, said means for generating having inputs connected respectively to outputs of said voltage detecting means, said sensor and said zero crossing detector, said command signal having a closing state which causes said electronic signal to close and connect said two input terminals by means of said switch only when said three positive output signals are received at said input of said means for generating, in such a manner that said first power supply is connected in series with said heating resistance in closed loop and thus supplies said electrical power to said resistance, said command signal further having a normally open state which causes said electronic switch to open for a whole number of power supply cycles from said first power supply so that said means for storing electrical energy of said second power supply is charged from said first power supply, said command signal being maintained in the open state as long as the three positive output signals are not generated.