Thermostat with occupancy detector

• US 5,819,840 A
• Filed: 12/13/1996
• Issued: 10/13/1998
• Est. Priority Date: 12/15/1995
• Status: Expired due to Fees

• Current Assignee: Don R. Wilson
• Original Assignee: Don R. Wilson
• Inventors: Downing, Harvey, Wilson, Don R.
• Primary Examiner(s): WAYNER, WILLIAM E
• Application Number:
  US08/766,293
• Time in Patent Office: 669 Days
• Field of Search: 165/237, 165/11.1, 165/238, 236/47, 236/46 R
• US Class Current: 165/11.1
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/46 Improving electric energy efficiency or saving
• CPC Class Codes: F24F 11/64 using pre-stored data
• CPC Class Codes: F24F 11/66 Sleep mode
• CPC Class Codes: F24F 11/67 Switching between heating and cooling modes
• CPC Class Codes: F24F 2120/10 Occupancy
• CPC Class Codes: G05D 23/1902 characterised by the use of a variable reference value

Abstract

An energy saving controller for an air conditioning system comprising a temperature sensor or sensing and measuring the temperature in an area to be controlled, a memory device for storing a first set and a second set of reference temperatures, each set of reference temperatures including a heating reference temperature and a cooling reference temperature, and a controller in communication with the memory device for selecting one of the first and second sets of reference temperatures in the memory and for comparing the selected set of reference temperatures to the measured temperature of the area. The controller is adapted to select one set of reference temperatures when the area is unoccupied by a person and to select the other set of reference temperatures when the area is occupied by a person. The occupancy information is provided to the controller by an occupancy detector. A system switch is provided that communicates with the controller and selects between a heating mode, a cooling mode, and an off mode. The controller is adapted to actuate a heating unit when the heating mode is selected by the system switch and when the measured temperature of the area falls substantially below the heating temperature set point or actuate a cooling unit when the cooling mode is selected by the system switch and when the measured temperature of the area substantially exceeds the selected cooling temperature set point.

Claims

1. An energy saving controller for an air conditioning system, the controller comprising:

temperature sensing means for sensing and measuring the temperature in an area to be controlled;

memory means for storing a first set and a second set of reference temperatures, each set of reference temperatures including a heating reference temperature and a cooling reference temperature;

control means in communication with said memory means for selecting one of said first and second sets of reference temperatures in said memory and for comparing the selected set of reference temperatures to the measured temperature of the area, said control means adapted to select one set of reference temperatures when the area is unoccupied by a person and to select the other set of reference temperatures when the area is occupied by a person, said control means in communication with an occupancy detector means for detecting the presence of a person in the area;

adjuster means having a first switch interconnected to said control means for selecting the set of reference temperatures stored in said memory means to be adjusted;

means for increasing and decreasing the reference temperatures selected by the first switch; and

system switch means for selecting between a heating mode, a cooling mode, and an off mode, said switch means interconnected with said control means, said control means adapted to actuate a heating unit when the heating mode is selected by said switch means and when the measured temperature of the area falls substantially below the heating temperature set point or actuating a cooling unit when the cooling mode is selected by said switch means and when the measured temperature of the area substantially exceeds the selected cooling temperature set point.

2. A thermostat assembly for controlling the temperature in an area according to claim 1, wherein said first switch comprises a key switch.

3. A thermostat assembly for controlling the temperature in an area according to claim 1, wherein said occupancy detector means comprises an infrared sensor.

4. A thermostat assembly for controlling the temperature in an area according to claim 1, further comprising display means for displaying the temperature set point which corresponds to the mode selected by the system switch means and the temperature measured by said temperature sensing means.

5. A thermostat assembly for controlling the temperature in an area according to claim 1, further comprising a power supply circuit for supplying power to the thermostat assembly, said power supply circuit adapted provide a direct current supply to the thermostat assembly from an alternating current power source, said power supply circuit including a back up direct current power source.

6. A thermostat assembly for controlling the temperature in an area, the control system comprising:

a thermostat assembly including;

sensor means for sensing and measuring the temperature in the area;

system switch means for switching between a heating mode, a cooling mode, and an off mode;

memory means for storing a first occupied set and a second unoccupied set of reference temperature values, each set of reference temperature values including a heating reference temperature value and a cooling reference temperature value;

selector means for selecting one of said first and second sets of reference temperatures stored in said memory means as temperature set points;

a switch to select between the first and second set of reference temperatures having a normal operating position wherein said first occupied set of reference temperatures is selected for adjustment and second position wherein said second unoccupied set of reference temperatures is selected for adjustment;

means to increment or decrement the temperatures selected by the switch;

logic means responsive to said selector means for comparing the selected temperature points to the temperature measured by the sensor means;

actuator means responsive to said logic means for actuating a heating unit when the heating mode is selected by the system switch means and when the measured temperature of the area falls substantially below the heating temperature set point and for actuating a cooling unit when the cooling mode is selected by the system switch means and when the measured temperature of the area substantially exceeds the selected cooling temperature set point, said actuator means responsive to said system switch means; and

an occupancy sensor assembly communicating with said selector means of said thermostat assembly, said selector means being adapted to select one set of reference temperatures as the temperature set points when the occupancy detector detects that the area is unoccupied and adapted to select the other set of reference temperatures as the temperature set points when the occupancy detector detects that the area is occupied.

7. A thermostat assembly for controlling the temperature in an area according to claim 6, wherein said occupancy sensor assembly includes an infrared sensor.

8. A thermostat assembly for controlling the temperature in an area according to claim 6, wherein said logic means comprises a micro-controller chip.

9. A thermostat assembly for controlling the temperature in an area according to claim 6, further comprising means for displaying the selected temperature set point that corresponds to the mode selected by the switch means and the temperature measured by said sensor means.

10. A thermostat assembly for controlling the temperature in an area, the control system comprising:

a thermostat assembly including;

temperature sensor means for sensing and measuring the temperature in the area;

a first switch for switching between a heating mode, a cooling mode, and an off mode;

a second switch for switching between an automatic mode and a fan-on mode;

memory means for storing a first set and a second set of reference temperature values, each set of reference temperature values including a heating reference temperature value and a cooling reference temperature value;

selector means for selecting one of said first and second sets of reference temperatures stored in said memory means as temperature set points;

a third switch for selecting a stored reference temperature value to be adjusted;

adjustor means for adjusting the stored reference temperature value as selected by the third switch;

logic means responsive to said selector means for comparing the selected temperature set points to the temperature measured by the sensor means;

actuator means responsive to said logic means for actuating a heating unit when the heating mode is selected by said first switch and when the measured temperature of the area falls substantially below the heating temperature set point or actuating a cooling unit when the cooling mode is selected by said first switch and when the measured temperature of the area substantially exceeds the selected cooling temperature set point; and

an occupancy sensor assembly communicating with said selector means of said thermostat assembly, said selector means being adapted to select one set of reference temperatures as the temperature set points when the occupancy detector detects that the area is unoccupied and adapted to select the other set of reference temperatures as the temperature set points when the occupancy detector detects that the area is occupied.

11. A thermostat assembly for controlling the temperature in an area according to claim 10, wherein said occupancy sensor comprises an infrared sensor.

12. A thermostat assembly for controlling the temperature in an area according to claim 10, wherein said logic means comprises a micro-controller chip.

13. A thermostat assembly for controlling the temperature in an area according to claim 10, wherein said third switch comprises a key switch.

14. A value adjustment mechanism for a thermostat, said thermostat having a memory means for storing a first and second set of reference temperature values, each said set including a heating and cooling reference temperature value, the value adjustment mechanism comprising:

a system switch for selecting heating or cooling modes;

a selector switch for selecting between the first and second set of reference temperature values;

a temperature selection means to increment or decrement the temperature value selected by the system and selector switches; and

a means for monitoring said system and selector switches and said temperature selection means to permit adjustment of said stored reference temperature values.

15. A method of temperature value adjustment on a thermostat having a memory means for storing a first occupied and second unoccupied set of reference temperature values, each set including a heating and cooling reference temperature value, said method comprising the steps of:

actuating a switch to select between the first and second sets of reference temperatures, said switch having a normal operating position wherein said first occupied set of reference temperatures is selected for adjustment and a second position wherein said second unoccupied set of reference temperatures is selected for adjustment;

establishing reference temperatures for the second unoccupied set of reference temperatures;

actuating the switch such that the reference temperatures for said second unoccupied set of reference temperatures can not be changed by unauthorized personnel;

selecting between a heating and cooling mode; and

selecting said first occupied set of reference temperatures if a source of heat is detected indicating that an area is occupied, and selecting said second unoccupied set of reference temperatures if a source of heat is not detected indicating that the area is not occupied.

16. A method of temperature value adjustment as in claim 15, wherein the step of actuating a switch to select between the first and second sets of reference temperatures comprises the step of:

turning a key switch.