Motorized window treatment

• US 9,605,478 B2
• Filed: 12/22/2014
• Issued: 03/28/2017
• Est. Priority Date: 03/11/2011
• Status: Active Grant

• Current Assignee: Lutron Technology Company LLC
• Original Assignee: Lutron Electronics Company Incorporated (Lutron Electronics)
• Inventors: Adams, Jason O., Blair, Edward J., Cooney, Andrew Karl, Jain, Soumya, Kirby, David A., Lundy, Stephen, Mierta, Justin J., Mistarz, Daniel W., Newman, Robert C. Jr., Ogden, Peter W. Jr., Roe, Jonathan L., Wu, Chen Ming, Zernhelt, Justin M.
• Primary Examiner(s): PUROL, DAVID M
• Application Number:
  US14/579,024
• Publication Number:
  US 20150159433A1
• Time in Patent Office: 827 Days
• Field of Search: 160/84.02, 160/168.1 P, 160/170, 160/171, 160/DIG.17
• US Class Current: 1/1
• CPC Class Codes: E06B 2009/2625 Pleated screens, e.g. concertina- or accordion-like
• CPC Class Codes: E06B 2009/6818 using sensors
• CPC Class Codes: E06B 2009/6872 using counters to determine shutter position
• CPC Class Codes: E06B 9/32 Operating, guiding, or securing devices therefor operation of tilting bars E06B9/307
• CPC Class Codes: E06B 9/322 Details of operating devices, e.g. pulleys, brakes, spring drums, drives operating devices E06B9/68 ; devices of general interest specially adapted or mounted for storing and repeatedly paying-out and re-storing lengths of material B65H75/34
• CPC Class Codes: E06B 9/38 Other details
• CPC Class Codes: E06B 9/62 Counterweighting arrangements E06B9/60 takes precedence
• CPC Class Codes: E06B 9/68 Operating devices or mechanisms, e.g. with electric drive
• CPC Class Codes: E06B 9/70 comprising an electric motor positioned outside the roller
• CPC Class Codes: E06B 9/72 comprising an electric motor positioned inside the roller
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0219 where the power saving management affects multiple terminals
• CPC Class Codes: H04W 52/0225 using monitoring of external events, e.g. the presence of a signal
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 52/0235 where the received signal is a power saving command
• CPC Class Codes: H04W 52/0238 where the received signal is an unwanted signal, e.g. interference or idle signal
• CPC Class Codes: H04W 52/0245 according to signal strength
• CPC Class Codes: H04W 52/028 switching on or off only a part of the equipment circuit blocks
• CPC Class Codes: H04W 52/0287 changing the clock frequency of a controller in the equipment
• CPC Class Codes: Y02A 30/24 Structural elements or technologies for improving thermal insulation
• CPC Class Codes: Y02B 80/00 : Architectural or constructional elements improving the thermal performance of buildings
• CPC Class Codes: Y02D 30/70 : in wireless communication networks

Abstract

A motorized window treatment provides a low-cost solution for controlling the amount of daylight entering a space through a window. The window treatment includes a covering material, a drive shaft, at least one lift cord rotatably received around the drive shaft and connected to the covering material, and a motor coupled to the drive shaft for raising and lowering the covering material. The window treatment also includes a spring assist unit for assisting the motor by providing a torque that equals the torque provided by the weight on the cords that lift the covering material at a position midway between fully-open and fully-closed positions, which helps to minimize motor usage and conserve battery life if a battery is used to power the motorized window treatment. The window treatment may comprise a photosensor for measuring the amount of daylight outside the window and temperature sensors for measuring the temperatures inside and outside of the window. The position of the covering material may be automatically controlled in response to the photosensor and the temperature sensors to save energy, or may also be controlled in response to an infrared or radio-frequency remote control.

Claims

1. A motorized window treatment comprising:

a headrail having first and second opposite ends;

a covering material having a top end connected to the headrail, the covering material extending from the headrail to a bottom end;

a motor drive unit including a motor and located in the center of the headrail;

two drive shafts extending from both sides of the motor drive unit and rotatably coupled to the motor drive unit thereby allowing rotations of the motor to result in rotations of the drive shafts;

first and second lift cords, the first lift cord located proximate to the first opposite end of the headrail and the second lift cord located proximate to the second opposite end of the headrail, each lift cord rotatably received around a respective one of the drive shafts and extending vertically to the bottom end of the covering material; and

at least a first compartment and a second compartment configured to hold respective first and second batteries for powering the motor drive unit, the first and second compartments located on each side of the motor drive unit, the first compartment located between the first opposite end of the headrail and the first lift cord, and the second compartment located between the second opposite end of the headrail and the second lift cord;

wherein the motor drive unit is configured to rotate the drive shaft to adjust the bottom end of the covering material between a fully-closed position and a fully-open position in response to rotations of the drive shaft, the motor drive unit further configured to receive radio-frequency (RF) signals and to control the motor in response to the received RF signals.

2. The motorized window treatment of claim 1, wherein the motor drive unit comprises an RF receiver configured to receive RF signals.

3. The motorized window treatment of claim 2, further comprising a battery-powered supply that includes the first and second batteries and generates a battery voltage.

4. The motorized window treatment of claim 3, wherein the motor drive unit is configured to monitor the magnitude of the battery voltage of the battery-powered supply, the battery-powered supply configured to enter a low-battery mode when the magnitude of the battery voltage drops below a first predetermined low-battery threshold.

5. The motorized window treatment of claim 4, wherein the RF receiver comprises an RF transceiver configured to transmit and receive RF signals.

6. The motorized window treatment of claim 5, wherein the motor drive unit is configured to transmit a digital message representative of the magnitude of the battery voltage.

7. The motorized window treatment of claim 5, wherein the motor drive unit is configured to transmit a digital message indicating that the battery voltage is low via the RF signals when operating in the low-battery mode.

8. The motorized window treatment of claim 4, wherein the RF receiver is disabled in the low-battery mode.

9. The motorized window treatment of claim 3, wherein the at least two batteries are electrically coupled in series to generate the battery voltage to power the motor drive unit.

10. The motorized window treatment of claim 9, wherein the motor drive unit comprises a positive-temperature coefficient thermistor coupled in series with the batteries for limiting the current drawn from the batteries.

11. The motorized window treatment of claim 3, wherein the motor drive unit is configured to prevent the motor from operating to lower the covering material until an upper limit for the covering material is reset after a loss of power.

12. The motorized window treatment of claim 9, wherein the at least two batteries comprise at least four D-cell batteries.

13. The motorized window treatment of claim 9, wherein the batteries have a lifetime of approximately three years.

14. The motorized window treatment of claim 2, wherein the motor drive unit further comprises a room-side interior temperature sensor configured to measure an interior temperature representative of the temperature in the room in which the window treatment is installed.

15. The motorized window treatment of claim 14, wherein the motor drive unit further comprises a window-side temperature sensor configured to measure an external temperature representative of the temperature outside a window in front of which the motorized window treatment is located.

16. The motorized window treatment of claim 15, wherein the RF receiver comprises an RF transceiver configured to transmit and receive RF signals, the motor drive unit configured to wirelessly transmit the exterior temperature via the RF signals.

17. The motorized window treatment of claim 15, wherein the motor drive unit is configured to adjust the position of the bottom end of the covering material in response to the external and internal temperatures.

18. The motorized window treatment of claim 14, wherein the RF receiver comprises an RF transceiver configured to transmit and receive RF signals, the motor drive unit configured to wirelessly transmit the interior temperature via the RF signals.

19. The motorized window treatment of claim 1, wherein the motor drive unit further comprises an H-bridge drive circuit and a controller, the controller configured to provide pulse width modulated (PWM) control signals to the H-bridge drive circuit for driving the motor to control the rotational speed of the motor.

20. The motorized window treatment of claim 19, wherein the controller is configured to ramp the rotational speed of the motor up from zero to a desired rotational speed across a ramp time when starting the motor from a stopped condition.

21. The motorized window treatment of claim 19, wherein the PWM control signals increase in duty cycle as the covering material is raised from the midway position to the fully-open position and when the covering material is lowered from the midway position to the fully-closed position.

22. The motorized window treatment of claim 1, wherein the motor drive unit further comprises a gear assembly operatively coupled to an output shaft of the motor and two output gears located on each side of the motor drive unit, each of the output gears coupled to one of the drive shafts, the motor drive unit further comprising a coupling member coupled between the gear assembly and the output gears allowing rotations of the output shaft of the motor to result in rotations of the drive shafts.

23. The motorized window treatment of claim 1, wherein the motor drive unit is configured to receive the RF signals from an RF transmitter, the RF transmitter comprising one of a battery-powered remote control, an occupancy sensor, a vacancy sensor, a daylight sensor, a temperature sensor, a humidity sensor, a security sensor, a proximity sensor, a keypad, a key fob, a cell phone, a smart phone, a tablet, a personal digital assistant, a personal computer, a timeclock, an audio-visual control, a safety device, a central control transmitter, or any combination of these RF transmitters.

24. A motor drive unit for a motorized window treatment, the motorized window treatment including a covering material, a drive shaft, and at least one lift cord rotatably received around the drive shaft and extending to a bottom of the covering material for raising and lowering the covering material, the motorized window treatment further comprising a battery-powered supply having at least one battery producing a battery voltage to power the motor drive unit, the motor drive unit comprising:

a motor; and

a controller configured to control the motor to rotate the drive shaft to raise and lower the covering material in response to received radio-frequency (RF) signals;

wherein the controller is configured to monitor the magnitude of the battery voltage of the battery-powered supply when the motor is not raising or lowering the covering material, the controller configured to enter a low-battery mode when the magnitude of the battery voltage drops below a first predetermined low-battery threshold and to move the covering material at a reduced speed in the low-battery mode.

25. The motor drive unit of claim 24, further comprising:

an RF receiver coupled to the controller and configured to receive RF signals.

26. The motor drive unit of claim 25, wherein the RF receiver comprises an RF transceiver configured to transmit and receive RF signals.

27. The motor drive unit of claim 26, wherein the controller is configured to transmit a digital message representative of the magnitude of the battery voltage.

28. The motor drive unit of claim 26, wherein the controller is configured to transmit a digital message indicating that the battery voltage is low via the RF signals when operating in the low-battery mode.

29. The motor drive unit of claim 25, wherein the RF transceiver is disabled in the low-battery mode.

30. A motorized window treatment comprising:

a covering material;

a motor drive unit configured to move the covering material between a fully-open position and a fully-closed position in response to received radio-frequency (RF) signals;

a battery-powered supply connected to and providing a voltage for powering the motor drive unit; and

wherein the motor drive unit is configured to determine when the magnitude of the voltage is too low for continued operation and reserve enough energy in the battery to allow for at least one additional movement of the covering material to the fully-open position.

31. The motorized window treatment of claim 30, wherein the motor drive unit comprises a motor coupled to the covering material and configured to adjust the position of the covering material to any position and a controller electrically connected to and configured to control the motor.

32. The motorized window treatment of claim 31, wherein the motor drive unit comprises an RF receiver configured to receive RF signals, the controller configured to disable the RF receiver when the magnitude of the voltage is too low for continued operation.

33. A motor drive unit for a motorized window treatment, the motorized window treatment including a covering material, a drive shaft, and at least one lift cord rotatably received around the drive shaft and extending to a bottom of the covering material for raising and lowering the covering material between a fully-open and fully-closed position and to any position intermediate the fully-open and fully-closed positions, the motorized window treatment further comprising a battery-powered supply having at least one battery for generating a battery voltage for powering the motor drive unit, the motor drive unit comprising:

a motor;

a controller configured to control the motor to rotate the drive shaft to raise and lower the covering material in response to received radio-frequency (RF) signals; and

a power supply configured to generate a DC supply voltage from the battery voltage, the DC supply voltage having a first nominal magnitude for powering the controller;

wherein the controller is configured to increase the magnitude of the DC supply voltage to a second increased magnitude greater than the first magnitude when the controller is driving the motor to rotate the drive shaft.

34. The motor drive unit of claim 33, further comprising:

an RF receiver coupled to the controller and configured to receive RF signals.

35. The motor drive unit of claim 34, wherein the RF receiver comprises an RF transceiver configured to transmit and receive RF signals, the controller configured to cause the RF transceiver to transmit a digital message representative of the battery voltage via the RF signals.

36. The motor drive unit of claim 34, wherein the RF receiver is configured to receive the RF signals from an RF transmitter, the RF transmitter comprising one of a battery-powered remote control, an occupancy sensor, a vacancy sensor, a daylight sensor, a temperature sensor, a humidity sensor, a security sensor, a proximity sensor, a keypad, a key fob, a cell phone, a smart phone, a tablet, a personal digital assistant, a personal computer, a timeclock, an audio-visual control, a safety device, a central control transmitter, or any combination of these RF transmitters.

37. The motor drive unit of claim 33, wherein the motor is connected to and powered directly from the battery voltage.

38. A motorized window treatment comprising:

a covering material for the window, the covering material moveable between a fully-open and fully-closed position and to any position intermediate the fully-open and fully-closed positions;

a drive shaft;

at least one lift cord rotatably received around the drive shaft and extending to a bottom of the covering material for raising and lowering the covering material;

a motor drive unit having a motor coupled to the drive shaft to rotate the drive shaft to raise and lower the covering material, the motor drive unit having a sensor arrangement coupled to the drive shaft to sense movement of the drive shaft and used to determine the position of the bottom of the covering material, the motor drive unit having a controller electrically coupled to the sensor arrangement to determine the position of the bottom of the covering material between the fully-open and fully-closed positions from at least one sensor signal from the sensor arrangement, the motor drive unit having a memory coupled to the controller to store position data related to the determined position, the controller configured to control the motor to raise and lower the covering material in response to received radio-frequency (RF) signal;

a battery-powered supply configured to power the motor drive unit;

a supplemental power source for the control unit, the supplemental power source configured to maintain a charged voltage for a period of time adequate to maintain the position data when the battery-powered supply is removed and changed;

whereby the battery-powered supply can be removed without loss of the position data.

39. The motorized window treatment of claim 38, wherein the RF signals are received from an RF remote control.

40. The motorized window treatment of claim 39, wherein the fully-open and fully-closed positions of the motorized window treatment may be adjusted by actuating one or more buttons on the remote control.

41. The motorized window treatment of claim 40, wherein the remote control is associated with the motorized window treatment by actuating an actuator on the motor drive unit and then actuating at least one of the buttons on the remote control.

42. The motorized window treatment of claim 39, further comprising:

an RF receiver coupled to the controller and configured to receive the RF signals.

43. The motorized window treatment of claim 39, further comprising:

an RF transceiver coupled to the controller and configured to transmit and receive RF signals.

44. The motorized window treatment of claim 38, wherein the supplemental power source comprises a capacitor coupled to the battery-powered supply.

45. The motorized window treatment of claim 38, wherein the supplemental power source comprises a further battery coupled to the control unit for providing power to the control unit to maintain power to the control unit when the battery-powered supply is removed.

46. The motorized window treatment of claim 38, wherein the memory comprises an internal memory of the controller.

47. A motorized window treatment comprising:

a covering material for a window moveable between a fully-open and a fully-closed position and any position intermediate the fully-open and fully-closed positions;

a drive shaft;

at least one lift cord rotatably received around the drive shaft and extending to a bottom of the covering material for raising and lowering the covering material;

a motor drive unit having a motor coupled to the drive shaft to rotate the drive shaft to raise and lower the covering material, the motor drive unit having a sensor arrangement coupled to the drive shaft to sense movement of the drive shaft and used to determine the position of the bottom of the covering material, the motor drive unit having a controller electrically coupled to the sensor arrangement to determine the position of the bottom of the covering material between the fully-open and fully-closed positions from at least one sensor signal from the sensor arrangement, the controller configured to control the motor to raise and lower the covering material in response to received radio-frequency (RF) signals;

wherein the covering material is engageable by a user to manually position the covering material at any position between the fully-open and fully-closed positions and wherein the sensor arrangement provides the at least one sensor signal to the controller so that the controller can determine the position of the covering material when the covering material is manually adjusted.

48. The motorized window treatment of claim 47, wherein the controller further comprises a microprocessor having a sleep mode, the microprocessor using reduced electrical power during the sleep mode to conserve battery power.

49. The motorized window treatment of claim 48, wherein the motor produces an electromotive force when the window treatment is moved manually, the microprocessor configured to be responsive to the electromotive force to cause the microprocessor to change from the sleep mode to an active mode, the microprocessor configured to receive and process the sensor signal to determine the position of the covering material when the covering material is manually adjusted.

50. The motorized window treatment of claim 48, wherein the motor drive unit comprises an RF receiver configured to receive RF signals, the controller configured to control the RF receiver into a sleep mode in which the RF receiver consumes less power.

51. A motorized window treatment comprising:

a covering material;

a drive shaft;

at least one lift cord rotatably received around the drive shaft and arranged to extend to a bottom end of the covering material in such a way that the lift cord provides a torque on the drive shaft;

a motor drive unit having a motor coupled to the drive shaft and configured to rotate the drive shaft to raise and lower the covering material in response to received radio-frequency (RF) signals, the motor drive unit configured to rotate the drive shaft to raise and lower the covering material between a fully-open position and a fully-closed position in response to the received RF signals; and

a spring assist assembly coupled to the drive shaft and configured to provide a constant amount of torque on the drive shaft in a direction opposite a direction of the torque provided on the drive shaft by the lift cord;

wherein an amount of energy required by the motor to drive the drive shaft is reduced by the spring assist assembly, and the constant amount of torque provided by the spring assist assembly is approximately equal to the torque provided on the drive shaft by the at least one lift cord when the bottom end of the covering material is positioned half-way between the fully-open position and the fully-closed position.

52. The motorized window treatment of claim 51, wherein an amount of energy required by the motor to drive the drive shaft is reduced by the spring assist assembly such that net energy is provided by the motor to raise the covering material during approximately half the distance between the fully-closed and fully-open position.

53. The motorized window treatment of claim 52, wherein net energy is provided by the motor when the covering material is raised between half-way and the fully-open position and when the covering material is lowered between half-way and the fully-closed position.

54. The motorized window treatment of claim 51, further comprising:

a plurality of batteries coupled in series and configured to generate a battery voltage for powering the motor drive unit.

55. The motorized window treatment of claim 54, wherein the batteries have a lifetime of approximately three years.

56. The motorized window treatment of claim 55, wherein the batteries comprise at least four D-cell batteries.

57. The motorized window treatment of claim 51, wherein the motor drive unit further comprises an RF receiver configured to receive the RF signals.

58. The motorized window treatment of claim 57, wherein the controller comprises a microprocessor configured to receive signals from the RF receiver and to control the RF receiver, the processor configured to control the RF receiver to place the RF receiver in a low power mode or turn the RF receiver off to conserve battery power.

59. The motorized window treatment of claim 51, wherein the motor drive unit further comprises an RF transceiver configured to transmit and receive RF signals.

60. The motorized window treatment of claim 51, wherein the spring assist assembly comprises a constant-force spring configured to provide the constant amount of torque on the drive shaft in a direction opposite a direction of the torque provided on the drive shaft by the lift cord.

61. The motorized window treatment of claim 51, wherein the spring assist assembly is configured provide a torque to the drive shaft to raise the covering material to a position approximately midway between the fully-closed and fully-open position without substantial energy being provided by the motor, the spring assist assembly configured to assist the motor to raise the covering material above the midway position to the fully-open position, the spring assist assembly configured to provide a torque on the drive shaft resisting downward motion of the covering material when the covering material is lowered from the fully-open position to the fully-closed position.

62. The motorized window treatment of claim 61, wherein the motor is configured to provide a torque on the drive shaft to wind up the spring assist unit when the covering material is lowered from the midway position to the fully-closed position.