Automatic momentary secondary light source assembly

• US 20050087675A1
• Filed: 09/08/2004
• Published: 04/28/2005
• Est. Priority Date: 09/08/2003
• Status: Active Grant

• Current Assignee: John Alfred Ayres
• Original Assignee: John Alfred Ayres
• Inventors: Ayres, John Alfred
• Granted Patent: US 7,253,570 B2
• Time in Patent Office: Days
• US Class Current: 250/214.R
• CPC Class Codes: G03B 27/54 Lamp housings; Illuminating means
• CPC Class Codes: H05B 47/11 by determining the brightness or colour temperature of ambient light
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

A secondary light assembly emits light into an area lit by a primary light source. The secondary light assembly includes a light sensor for sensing light emitted from the primary light source. A secondary light source is operatively connected to the light sensor. A controller is electrically connected to the light sensor and the secondary light source. The controller calculates a rate of change of light emission from the primary light source such that the controller turns the secondary light source on when the rate of change of light emission from the primary light source is above a predetermined rate threshold.

Claims

1. A secondary light assembly for emitting light into an area lit by a primary light source, said secondary light assembly comprising:

a light sensor for sensing light emitted from the primary light source;

a secondary light source operatively connected to said light sensor; and

a controller electrically connected to said light sensor and said secondary light source, said controller calculating a rate of change of light emission from the primary light source such that said controller turns on said secondary light source when the rate of change of light emission from the primary light source is above a predetermined rate threshold.

2. A secondary light assembly as set forth in claim 1 wherein said controller includes a timer to measure an amount of time beginning when said controller turns said secondary light source on.

3. A secondary light assembly as set forth in claim 2 including a reset switch for turning said secondary light source off when said timer measures said predetermined amount.

4. A secondary light assembly as set forth in claim 3 wherein said controller includes a soft off circuit for ramping down the amount of light emitted by said secondary light source at a ramp down rate that is less than said predetermined rate threshold.

5. A secondary light assembly as set forth in claim 3 wherein said light sensor defines a range in an electromagnetic wavelength spectrum that can be sensed by said light sensor.

6. A secondary light assembly as set forth in claim 5 wherein said secondary light source emits light outside said range defined by said light sensor.

7. A secondary light assembly as set forth in claim 3 wherein said controller includes a primary switch port for receiving a signal from a primary light switch operatively connected to the primary light source, said controller activating said secondary light when the signal from the primary light switch indicates the primary light was turned off at a rate greater than said predetermined rate threshold.

8. A secondary light assembly as set forth in claim 7 wherein said controller includes an OR gate for activating said secondary light when the primary light switch is turned off or when said controller calculates the rate of change of light emission to be above said predetermined rate threshold.

9. A secondary light assembly as set forth in claim 8 including a manual on switch for turning said secondary light source on independently of activity of the primary light source.

10. A secondary light assembly as set forth in claim 3 including an isolation switch for preventing light emitted from said secondary light source to be incorporated into the calculation by said controller when measuring the rate of change of light emission.

11. A secondary light assembly as set forth in claim 10 including an adjuster for adjusting said timer and the time during which said secondary light source is on.

12. A secondary light assembly for emitting light into an area lit by a primary light source, said secondary light assembly comprising:

a light sensor for sensing light emitted from the primary light source;

a secondary light source operatively connected to said light sensor;

a controller electrically connected to said light sensor and said secondary light source, said controller calculating a rate of change of light emission from the primary light source such that said controller turns on said secondary light source when the rate of change of light emission from the primary light source is above a predetermined rate threshold; and

a soft off circuit for ramping down the amount of light emitted by said secondary light source at a ramp down rate that is less than said predetermined rate threshold.

13. A secondary light assembly as set forth in claim 12 wherein said controller includes a primary switch port for receiving a signal from a primary light switch operatively connected to the primary light source, said controller activating said secondary light when the signal from the primary light switch indicates the primary light was turned off at a rate greater than said predetermined rate threshold.

14. A secondary light assembly as set forth in claim 13 wherein said controller includes an OR gate for activating said secondary light when the primary light switch is turned off or when said controller calculates the rate of change of light emission to be above said predetermined rate threshold.

15. A secondary light assembly as set forth in claim 14 including a manual on switch for turning said secondary light source on independently of activity of the primary light source.

16. A secondary light assembly as set forth in claim 15 including an isolation switch for preventing light emitted from said secondary light source to be incorporated into the calculation by said controller when measuring the rate of change of light emission.

17. A secondary light assembly as set forth in claim 16 including an adjuster for adjusting said timer and the time during which said secondary light source is on.

18. A secondary light assembly for emitting light into an area lit by a primary light source, said secondary light assembly comprising:

a light sensor for sensing light emitted from the primary light source;

a secondary light source operatively connected to said light sensor;

a manual switch operatively connected to said secondary light source for turning said secondary light source on and off; and

a controller electrically connected to said light sensor, said secondary light source and said manual switch, said controller turning on said secondary light source a first predetermined time when said light sensor senses the turning off of the primary light source, and said controller turning on said secondary light source a second predetermined time greater than said first predetermined time when said manual switch is closed.

19. A secondary light assembly as set forth in claim 18 wherein said controller includes a rate of light change circuit for measuring the rate of change of light emission from the primary light source.

20. A secondary light assembly as set forth in claim 19 including a rate threshold switch to compare the rate of change of light to a threshold rate.