Method of automatically controlling motorized window treatments

• US 10,041,293 B2
• Filed: 05/01/2017
• Issued: 08/07/2018
• Est. Priority Date: 12/23/2013
• Status: Active Grant

• Current Assignee: Lutron Technology Company LLC
• Original Assignee: Lutron Electronics Company Incorporated (Lutron Electronics)
• Inventors: Gill, Timothy
• Primary Examiner(s): Johnson, Blair M
• Application Number:
  US15/583,600
• Publication Number:
  US 20170234068A1
• Time in Patent Office: 463 Days
• CPC Class Codes: E06B 2009/6809 Control
• CPC Class Codes: E06B 2009/6818 using sensors
• CPC Class Codes: E06B 2009/6827 sensing light
• CPC Class Codes: E06B 2009/6845 sensing position
• CPC Class Codes: E06B 9/11 Roller shutters
• CPC Class Codes: E06B 9/40 Roller blinds usable only as awnings E04F10/06
• CPC Class Codes: E06B 9/68 Operating devices or mechanisms, e.g. with electric drive
• CPC Class Codes: G05B 13/024 in which a parameter or coefficient is automatically adjusted to optimise the performance
• 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

Abstract

A load control system automatically controls the amount of daylight entering a building through at least one window of a non-linear façade of the building. The load control system comprises at least two motorized window treatments located along the non-linear façade, and a system controller. The controller is configured to calculate an optimal position for the motorized window treatments at each of a plurality of different times during a subsequent time interval using at least two distinct façade angles of the non-linear façade, such that a sunlight penetration distance will not exceed a maximum distance during the time interval. The controller is configured to use the optimal positions to determine a controlled position to which both of the motorized window treatments will be controlled during the time interval and to automatically adjust each of the motorized window treatments to the controlled position at the beginning of the time interval.

Claims

1. A load control system for controlling an amount of daylight entering a space of a building through at least one window of a non-linear facade of the building, the non-linear facade characterized by at least two distinct facade angles, the load control system comprising:

at least two motorized window treatments located along the non-linear facade-for controlling the amount of daylight entering the space; and

a system controller configured to;

calculate a plurality of window treatment positions for a given time using the at least two distinct facade angles, the plurality of window treatment positions calculated to prevent a sunlight penetration distance from exceeding a defined sunlight penetration distance at the given time;

use the calculated plurality of window treatment positions for the given time to determine a controlled position to which each of the at least two motorized window treatments will be controlled; and

transmit the controlled position to the at least two motorized window treatments for adjusting a position of each of the at least two motorized window treatments; and

wherein each of the at least two motorized window treatments is configured to receive the controlled position from the system controller and to move to the controlled position so as to prevent the sunlight penetration distance from exceeding the defined sunlight penetration distance.

2. The load control system of claim 1, wherein to calculate the plurality of window treatment positions comprises to calculate a first position for a first of the at least two motorized window treatments arranged at a first facade angle, and to calculate a second position for a second of the at least two motorized window treatments arranged at a second facade angle.

3. The load control system of claim 2, wherein to use the calculated plurality of window treatment positions to determine the controlled position comprises to determine a lowest position of the first and second positions, and to set the controlled position equal to the lowest position of the first and second positions.

4. The load control system of claim 3, wherein the first and second facade angles comprise, respectively, a start facade angle and an end facade angle of a portion of the non-linear facade on which the at least two motorized window treatments are located.

5. The load control system of claim 3, wherein the first and second facade angles comprise distinct angles at which the first and second motorized window treatments of the at least two motorized window treatments are oriented, respectively.

6. The load control system of claim 1, wherein to calculate the plurality of window treatment positions comprises to calculate a first position at a first facade angle, and to calculate a second position at a second facade angle, wherein the first and second facade angles comprise, respectively, a start facade angle and an end facade angle of a portion of the non-linear facade on which the at least two motorized window treatments are located.

7. A load control system for controlling an amount of daylight entering a space of a building through at least one window of a non-linear facade of the building, the non-linear facade characterized by at least two distinct facade angles, the load control system comprising:

at least two motorized window treatments located along the non-linear facade for controlling the amount of daylight entering the space; and

a system controller configured to;

determine a representative facade angle for a given time using the at least two distinct facade angles;

calculate a controlled position for the at least motorized window treatments for the given time using the representative facade angle, the controlled position calculated to prevent a sunlight penetration distance from exceeding a defined sunlight penetration distance at the given time;

transmit the controlled position to the at least two motorized window treatments for adjusting a position of each of the at least two motorized window treatments; and

wherein each of the at least two motorized window treatments is configured to receive the controlled position from the system controller and to move to the controlled position so as to prevent the sunlight penetration distance from exceeding the defined sunlight penetration distance.

8. The load control system of claim 7, wherein the at least two distinct facade angles comprise first and second facade angles, and wherein to determine the representative facade angle further comprises to calculate a solar azimuth angle for the given time, and to determine the representative facade angle based on the first and second facade angles and the solar azimuth angle.

9. The load control system of claim 8, wherein to determine the representative facade angle further comprises to set the representative facade angle equal to the solar azimuth angle when the solar azimuth angle is between the first and second facade angles.

10. The load control system of claim 9, wherein to determine the representative facade angle further comprises to set the representative facade angle equal to the first facade angle when the solar azimuth angle is not between the first and second facade angles and the solar azimuth angle is closer to the first facade angle than the second facade angle, and to set the representative facade angle equal the second facade angle when the solar azimuth angle is not between the first and second facade angles and the solar azimuth angle is closer to the second facade angle than the first facade angle.

11. The load control system of claim 10, wherein the first and second facade angles comprise, respectively, a start facade angle and an end facade angle of a portion of the non-linear facade on which the at least two motorized window treatments are located, and wherein to calculate the solar azimuth angle further comprises to calculate the solar azimuth angle as a function of a longitude and a latitude of a location of the building, a present date, and the given time.

12. The load control system of claim 8, wherein the first and second facade angles comprise, respectively, a start facade angle and an end facade angle of a portion of the non-linear facade on which the at least two motorized window treatments are located.

13. The load control system of claim 8, wherein to calculate the solar azimuth angle further comprises to calculate the solar azimuth angle as a function of a longitude and a latitude of a location of the building, a present date, and the given time.

14. A method for controlling at least two motorized window treatments located along a non-linear faç

ade of a building, the non-linear faç

ade characterized by at least two distinct faç

ade angles, the method comprising;

calculating by a processor a plurality of window treatment positions for a given time using the at least two distinct facade angles, the plurality of window treatment positions calculated to prevent a sunlight penetration distance from exceeding a defined sunlight penetration distance at the given time;

using by the processor the calculated plurality of window treatment positions to determine a controlled position; and

adjusting by the processor a position of each of the at least two motorized window treatments to the controlled position so as to prevent the sunlight penetration distance from exceeding the defined sunlight penetration distance.

15. The method of claim 14, wherein calculating the plurality of window treatment positions comprises calculating a first position for a first of the at least two motorized window treatments arranged at a first facade angle, and calculating a second position for a second of the at least two motorized window treatments arranged at a second facade angle.

16. The method of claim 15, wherein using the calculated plurality of window treatment positions to determine the controlled position comprises determining a lowest position of the first and second positions, and setting the controlled position equal to the lowest position of the first and second positions.

17. The method of claim 16, wherein the first and second facade angles comprise, respectively, a start facade angle and an end facade angle of a portion of the non-linear facade on which the at least two motorized window treatments are located.

18. The method of claim 16, wherein the first and second facade angles comprise distinct angles at which the first and second motorized window treatments of the at least two motorized window treatments are oriented, respectively.

19. The method of claim 14, wherein calculating the plurality of window treatment positions comprises calculating a first position at a first facade angle, and calculating a second position at a second facade angle, wherein the first and second facade angles comprise, respectively, a start facade angle and an end facade angle of a portion of the non-linear facade on which the at least two motorized window treatments are located.

20. The method of claim 14, wherein adjusting the position of each of the at least two motorized window treatments to the controlled position comprises transmitting the controlled position to the at least two motorized window treatments for adjusting the position of each of the at least two motorized window treatments to the controlled position.