Thermostat with self-configuring connections to facilitate do-it-yourself installation

• US 9,116,529 B2
• Filed: 10/01/2014
• Issued: 08/25/2015
• Est. Priority Date: 02/24/2011
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Warren, Daniel Adam, Fiennes, Hugo, Dutra, Jonathan Alan, Bell, David, Fadell, Anthony Michael, Rogers, Matthew Lee, Filson, John Benjamin, Bould, Fred
• Primary Examiner(s): Elve, M. Alexandra
• Assistant Examiner(s): CRENSHAW, HENRY T
• Application Number:
  US14/504,220
• Publication Number:
  US 20150034729A1
• Time in Patent Office: 328 Days
• Field of Search: 307/119, 307/17, 307/125, 307/12, 307/147, 307/116, 439/28, 439/29, 236/1.C, 200/51.09, 200/51.1, 165/119
• US Class Current: 1/1
• 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 11/38 Failure diagnosis
• CPC Class Codes: F24F 11/52 Indication arrangements, e.g. displays
• CPC Class Codes: F24F 11/56 Remote control
• CPC Class Codes: F24F 11/58 using Internet communication
• CPC Class Codes: F24F 11/61 using timers
• CPC Class Codes: F24F 11/66 Sleep mode
• CPC Class Codes: F24F 11/86 by controlling compressors within refrigeration or heat pump circuits
• CPC Class Codes: F24F 11/88 Electrical aspects, e.g. circuits
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: F24F 2120/00 Control inputs relating to users or occupants
• CPC Class Codes: F24F 2120/14 Activity of occupants
• CPC Class Codes: G05B 2219/2614 HVAC, heating, ventillation, climate control
• CPC Class Codes: G05B 2219/2642 Domotique, domestic, home control, automation, smart house
• CPC Class Codes: G05D 23/19 characterised by the use of electric means G05D23/1393 takes precedence
• CPC Class Codes: G05D 23/1902 characterised by the use of a variable reference value
• CPC Class Codes: H01R 43/26 for engaging or disengaging the two parts of a coupling device structural association with two-part coupling device H01R13/629
• CPC Class Codes: Y02T 10/88 Optimized components or subsystems, e.g. lighting, actively controlled glasses
• CPC Class Codes: Y10T 29/49174 Assembling terminal to elongated conductor
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

A thermostat compatible with single-HVAC- and dual-HVAC-transformer systems may include a first power return wire connector, a second power return wire connector, and a user-moveable mechanical element that physically blocks wire insertion into the first wire connector when in a first position and physically allows wire insertion into the first wire connector when in a second position. The thermostat may also include a switching circuit that may be in a first configuration when the mechanical element is in the first position, and in a second configuration when the mechanical element is in the second position. The first wire connector may be electrically coupled to the second wire connector in the first configuration, and first wire connector may be electrically isolated from the second wire connector in the second configuration to promote foolproofing against undesired isolation of the first and second wire connectors.

Claims

1. A thermostat compatible with single-HVAC- transformer systems and dual-HVAC-transformer systems, the thermostat comprising:

a plurality of HVAC wire connectors configured for receiving a corresponding plurality of HVAC control wires, wherein the plurality of HVAC wire connectors includes a first call relay wire connector, a first power return wire connector, a second call relay wire connector, and a second power return wire connector, the first power return wire connector comprising a first opening configured to receive a corresponding first power return wire from the HVAC system, the second power return wire connector comprising a second opening configured to receive a corresponding second power return wire from the HVAC system;

a moveable mechanical element that is moveable between a first position and a second position, the moveable mechanical element physically blocking wire insertion into said first power return wire connector when in said first position and physically allowing wire insertion into said first power return wire connector when in said second position; and

a switching circuit coupled to said moveable mechanical element and to said first and second power return wire connectors, said switching circuit being in a first configuration when said moveable mechanical element is in said first position, and said switching circuit being in a second configuration when said moveable mechanical element is in said second position;

wherein said first configuration of said switching circuit is characterized in that said first power return wire connector is electrically coupled to said second power return wire connector during thermostat operation; and

wherein said second configuration of said switching circuit is characterized in that said first power return wire connector is electrically isolated from said second power return wire connector during thermostat operation when first and second HVAC power return wires are inserted respectively into said first and second power return wire connectors, and wherein said isolation therebetween cannot occur unless said moveable mechanical element has been moved to said second position, which second position is required in order to allow insertion of the first power return wire into said first power return wire connector.

2. The thermostat of claim 1, wherein said switching circuit comprises a first switch element coupled between said first power return wire connector and said second power return wire connector, wherein said first switch element is closed when said moveable mechanical element is in said first position, and wherein said first switch element is open when said moveable mechanical element is in said first position.

3. The thermostat of claim 2, wherein said switching circuit comprises a second switch element coupled between said first power return wire connector and said second power return wire connector, wherein said second switch element is closed when no wire is inserted into the second power return wire connector, and wherein said second switch element is open when the second power return wire is inserted into the second power return wire connector.

4. The thermostat of claim 1, wherein said thermostat is originally provided with said moveable mechanical element in said first position, said moveable mechanical element remaining in said first position unless it is moved to said second position.

5. The thermostat of claim 1, further comprising a head unit and a backplate, the head unit being configured for removable attachment to the backplate, the head unit having a graphical user interface and a plurality of temperature sensors and a processing system, the backplate containing said plurality of HVAC wire connectors and being configured for affixation to a wall during installation whereby installation of the thermostat comprises affixing the backplate to the wall, inserting the plurality of HVAC wires into respective ones of the plurality of HVAC wire connectors, and attaching the head unit to the backplate;

wherein the isolation of said first and second power return wire connectors is achieved solely by virtue of said positioning of said moveable mechanical element for the insertion of applicable ones of the first and second power return wires during installation such that the isolation of said first and second power return wire connectors does not require use of the processing system of the head unit.

6. The thermostat of claim 5, further comprising inductive isolation circuitry configured to protect said processing system and associated internal thermostat control circuits from anomalous voltage and/or current surges received through the plurality of HVAC wire connectors.

7. The thermostat of claim 6, wherein said inductive isolation circuitry is disposed on a printed circuit card housed within said back plate.

8. The thermostat of claim 1, further comprising a head unit and a backplate, the head unit being configured for removable attachment to the backplate, the head unit having a graphical user interface and a plurality of temperature sensors and a processing system, the backplate containing said plurality of HVAC wire connectors and being configured for affixation to a wall during installation whereby installation of the thermostat comprises affixing the backplate to the wall, inserting respective ones of the plurality of HVAC wires into the plurality of HVAC wire connectors, and attaching the head unit to the backplate, wherein:

said backplate is circular in shape and comprises an opening near a middle thereof through which the HVAC wires are received for insertion into the HVAC wire connectors; and

said first power return wire connector and said moveable mechanical element are mutually configured such that the moveable mechanical element is moved between said first and second positions in a direction that is generally perpendicular to a direction of insertion of the first power return wire into the first power return wire connector.

9. A compact thermostat comprising:

a frustum-shaped shell body having first and second ends, a circular cross-section, and a central axis generally perpendicular to a wall when the thermostat is wall-mounted, the first end of the frustum-shaped shell body being wall-facing when the thermostat is wall- mounted, the first end of the frustum-shaped shell body having a first diameter and the second end of the frustum-shaped shell body having a second, larger diameter;

a circular rotatable ring mounted proximate the second end of the frustum-shaped shell body, the circular rotatable ring including an axis of rotation generally perpendicular to the wall when the thermostat is wall-mounted, the circular rotatable ring being configured to be rotatable about the axis of rotation, wherein rotation of the circular rotatable ring results in input for adjusting a temperature setting of the thermostat;

a circular wall-mountable back plate configured to allow detachable coupling of the frustum-shaped shell body thereonto, the back plate comprising a plurality of HVAC wire connectors configured for receiving a corresponding plurality of HVAC control wires, wherein the plurality of HVAC wire connectors includes a first call relay wire connector, a first power return wire connector, a second call relay wire connector, and a second power return wire connector, the back plate including a first opening away from a periphery thereof through which the plurality of HVAC control wires can be routed for insertion into respective ones of the HVAC wire connectors, the first power return wire connector having a second opening for allowing an insertion of a corresponding first power return wire from the HVAC system;

a pressable element that can be mechanically actuated from a first position to a second position, wherein when pressable element is in the first position, the opening of the first power return wire connector is blocked such that the corresponding first power return wire from the HVAC system cannot be inserted into the first power return wire connector, and wherein when the pressable element is in the second position, the opening of the first power return wire connector is not blocked such that the corresponding first power return wire from the HVAC system can be inserted into the first power return wire connector; and

a switch coupled between the first power return wire connector and the second power return wire connector, wherein when the pressable element is in the first position, the switch operates to establish an electrical connection between the first power return wire connector to the second power return wire connector, and wherein when the pressable element is in the second position, the switch operates to electrically isolate the first power return wire connector from the second power return wire connector.

10. The thermostat of claim 9, wherein the pressable element and said first power return wire connector are mutually configured such that said pressable element is moved between said first and second positions in a direction that is generally perpendicular to a direction of insertion of the first power return wire into the first power return wire connector.

11. The thermostat of claim 10, wherein said direction of movement of said pressable element between said first and second positions is toward the wall when the backplate is wall-mounted.

12. The thermostat of claim 9, further comprising a processing system that detects an actuation of the pressable element and correspondingly actuates the switch, wherein the switch comprises an electrical switch.

13. The thermostat of claim 9, further comprising:

one or more temperature sensors positioned within the housing and obtaining temperature readings within an enclosure; and

a thermostatic control circuit coupled to the one or more temperature sensors, located within the housing, and configured to at least partially control the operation of the HVAC system responsive to temperature readings from the one or more temperature sensors, the thermostatic control circuit including a first switching device that operatively connects the first call relay wire connector to the first power return wire connector to control a first HVAC function , the thermostatic control circuit also including a second switching device that operatively connects the second call relay wire connector to the second power return wire connector to control a second HVAC function.

14. The thermostat of claim 9, further comprising:

a non-circular dot-matrix color display element mounted at a location between the second end of the frustum-shaped shell body and a circular cover, the circular cover having a clear circular center portion permitting a corresponding circular portion of the non-circular dot- matrix color display element to be visible therethrough, the circular cover having an opaque outer portion that masks a remaining portion of the non-circular dot-matrix color display element so as to create a circular graphical user interface; and

a motion sensor that detects user presence, wherein the processing system, upon receiving from the motion sensor a signal indicating user presence, activates the non-circular dot- matrix color display element.

15. The thermostat of claim 9, wherein the wall-mountable back plate comprises inductive isolation to protect internal thermostat control circuits from anomalous voltage and/or current surges received through the plurality of HVAC wire connectors.

16. The thermostat of claim 9, wherein the frustum-shaped shell body comprises a sidewall extending along the axis between its first and second circular ends, the sidewall having a circular cross section which, when sliced generally perpendicular to the axis, increases in diameter along the axis from the first to the second circular end such that an acute angle is formed between an outer surface of the sidewall and a wall when the thermostat is wall-mounted.

17. A method for facilitating installation of a thermostat that is compatible with both single-HVAC-transformer systems and dual-HVAC- transformer systems, the method comprising:

receiving a plurality of HVAC control wires through an opening in a wall- mountable back plate, wherein the plurality of HVAC control wires are received by a corresponding plurality of HVAC wire connectors, wherein the plurality of HVAC wire connectors includes a first call relay wire connector, a first power return wire connector, a second call relay wire connector, and a second power return wire connector, and wherein the first power return wire connector comprises an opening configured to receive a corresponding first power return wire from the HVAC system;

receiving a mechanical actuation of a pressable element from a first position to a second position, wherein when the pressable element is in the first position, the opening of first power return wire connector is blocked such that the corresponding first power return wire from the HVAC system cannot be inserted into the first power return wire connector, and wherein when the pressable element is in the second position, the opening of the first power return wire connector is not blocked such that the corresponding first power return wire from the HVAC system can be inserted into the first power return wire connector; and

in response to receiving the mechanical actuation of the pressable element from the first position to the second position, causing a switch circuit that is coupled between the first power return wire connector and the second power return wire connector to change from a first configuration to a second configuration, wherein said first configuration is characterized in that the switch circuit establishes an electrical connection between said first power return wire connector and the second power return wire connector, and wherein said second configuration is characterized in that the switch circuit does not establish the electrical connection between the first power return wire connector and the second power return wire connector.

18. The method of claim 17, further comprising originally providing said thermostat with said pressable element in said first position such that said pressable element remains in said first position unless it is moved to said second position by the user.

19. The method of claim 18, said switching circuit comprising a first switch element coupled between said first power return wire connector and said second power return wire connector, said first switch element being closed when said moveable mechanical element is in said first position, wherein said causing the switch circuit to change from the first configuration to the second configuration comprises causing the first switch element to open.

20. The thermostat of claim 18, wherein the pressable element and said first power return wire connector are mutually configured such that said pressable element is moved between said first and second positions in a direction that is generally perpendicular to a direction of insertion of the first power return wire into the first power return wire connector.