Claims
- 1. A system for controlling electrical power to a load comprising, in combination:
- (a) a dimming system to control power to said load in accordance with a signal provided by a control means, which includes an actuator positionable for determining the value of said control signal,
- (b) override means to permit power to said load when said actuator is positioned for power to said load to be off, and
- (c) a first switch means, which
- (i) if power to said load is on, turns said power off; and
- (ii) if power to said load is off, turns said power on to a value determined either by said actuator position or by said override means.
- 2. The system of claim 1 in which said control means comprises a linear slide potentiometer.
- 3. The system of claim 1 in which said control means comprises a rotary potentiometer.
- 4. The system of claim 1 in which said first switch means is a momentary contact switch.
- 5. The system of claim 1, further comprising at least one additional switch means to alternatively perform the functions of said first switch means.
- 6. The system of claim 1, further comprising means for adjusting the power provided to said load by said override means.
- 7. The system of claim 1 in which said override means comprises a second switch means that is turned on only when said actuator is positioned for power to said load to be off.
- 8. The system of claim 1 in which said load is a lighting load.
- 9. The system of claim 1, further comprising means for automatically applying to said load, substantially instantaneously upon positioning of said actuator, a power value determined by said control signal.
- 10. A system for controlling electrical power to a load comprising, in combination:
- (a) a dimming system to control power to said load in accordance with a signal provided by a control means, which includes an actuator positionable for determining the value of said control signal,
- (b) means for automatically applying to said load, substantially instantaneously upon positioning of said actuator, a power value determined by said control signal, and
- (c) a first switch means, which
- (i) if power to said load is on, turns said power off; and
- (ii) if power to said load is off, turns said power on to a value determined by said actuator position.
- 11. The system of claim 10 in which said control means comprises a linear slide potentiometer.
- 12. The system of claim 10 in which said control means comprises a rotary potentiometer.
- 13. The system of claim 10 in which said first switch means is a momentary contact switch.
- 14. The system of claim 10 further comprising at least one additional switch means to alternatively perform the functions of said first switch means.
- 15. The system of claim 10 in which said load is a lighting load.
CROSS REFERENCE TO PRIOR APPLICATION
This is a continuation-in-part of application Ser. No. 857,739, now U.S. Pat. No. 4,689,547 filed Apr. 29, 1986.
This invention relates to a multiple location control system and more particularly to a novel multiple location electrical load dimmer system incorporating switching that permits any one of the dimmer control units of interest to assume control of the load.
Dimming devices operable from a plurality of locations are well known, as are switching systems that are operable from a plurality of locations to cause switching of an electrical load. For example, the "Versaplex" system of Lutron Electronics Co., Inc., uses multiple low voltage controls each having a "take command" switch. A large number of systems employ multiple raise/lower switches to operate motor controlled dimmers. Yet other systems are decribed in U.S Pat. Nos. 3,697,821, 4,563,592 and others.
Typically, single location dimming with multiple switch location has been provided by a phase controlled dimmer with a manually operable, linearly or rotably movable potentiometer control, which dimmer may be combined with a series-connected single-pole, double-throw (three-way) switch in a wall box, and coupled with one or more series-connected three-way or four-way switches. In such a system all wiring and switches are rated to carry full load current. An alternative system is described in U.S. Pat. No. 4,563,592 that allows dimming from one location and switching from a plurality of locations. The wiring to the remote switching locations carries only signal power and the switches can be short-throw, light-force switches with a high tactile feel.
Alternatively, touch control systems have been provided in which each touch plate controls both switching and dimming level of a common dimmer. In such a system, one must wait until a newly desired light level is attained, and there is no indication of what the light level setting is when the lights are off. Such systems are sensitive to A.C. wiring polarity and loss of the previous switching and light level conditions in the event of temporary power loss. A serious disadvantage of such systems is that the touch plate wiring cannot be near load wiring. Some of these prior art systems generally require an overt act such as the deliberate manipulation of a separate switch, independently of the dimming control, as a distinct act on the part of the user to take command of control of the system at a given location. Accordingly, a principal object of the present invention is to provide an electrical load dimming system incorporating switching that permits control of on-off and adjustment of lighting level at a plurality of locations, transfer of control being conferred among such locations automatically simply upon actuation of the lighting level adjustment by the user at the desired location. Other objects of the present invention are to provide such a dimming system in which the light level falls and rises immediately as the lighting level adjustment is manipulated by the user, i.e. without any delay such as is present in motor controlled dimmers; to provide such a dimming system in which the lighting level is established immediately by the position at which the lighting level adjustment is set by the user; to provide such a dimming system in which such lighting level control can occur at any of a plurality of locations; and to provide such a dimming system in which, in the event of a power supply failure, the lighting level status of the load and which one of a plurality of remote controls is in command are maintained. A further object of the present invention is to provide an electrical load dimming system incorporating switching that provides control of the on-off and adjustment of lighting level at a plurality of locataions independently of the setting of the actuators at the other locations, and with only two connecting wires between each location. Another object of the present invention is to provide a multiple location electrical load dimming system that permits an on-off switch to provide power to a load, even if an operative dimmer control has been positioned for power to the load to be off.
To effect these and other objects, the present invention generally comprises a novel multiple location system for controlling application of alternating-current power to a load, employing a controllable bidirectional switch as a power carrying device, such as a triac, the gate control circuit for which has been modified to include auxiliary switching. Means, such as potentiometers, (linear or rotary), or proximity detectors, are disposable at various different locations for determining, responsively to the setting or positioning of an actuator such as the slide control of a potentiometer, the magnitude of respective control signals substantially immediately upon setting of the actuator. The signals are mutually exclusively applied to control the bidirectional switch in accordance with which one of the actuators is being set. Alternatively, the control signals can be applied in accordance with which one of a series of take-command switches at each location was last operated. In one embodiment, the actuator controls a pair of momentary-close switching means associated therewith (e.g. such as a mechanical push button switch spring loaded so as to relax except when under pressure), the switching means being ganged or operable in tandem for alternative operation such that a first of the switching means or push buttons closes and the second remains open, for example during movement of a potentiometer control slider in one direction, the first remaining open and the second being closed during motion of the slider in the other direction. The system of the invention includes an auxilary switching circuit, for example a magnetic latching relay, for conferring dimming control on that potentiometer control in which closure of one of the momentary-close switching means has last occurred. Other auxiliary switching circuits are possible including the use of microcomputers for that purpose.
The present invention therefore advantageously provides dimming from a plurality of control locations in a continuous manner such that the current flowing to the load instantly tracks and is established by the position of one of a plurality of actuators. Further, transfer of control to one among the several actuators occurs simply upon manipulation of the actuator, and without any other overt act by the user. The system of the present invention is compatible with a wide variety of possible techniques for detecting actuator manipulation, such as electronic detection of slider motion, capacitive or other touch plates, breaking or reflecting optical or infrared beams, piezoelectric sensors, strain gauges, varying resistances and mechanical motion of a push button. Particularly advantageous is the ease with which the present invention can be retrofitted to existing three-way wiring systems that use three-way and four-way switches.
Other objects of the present invention will in part appear obvious and will in part appear hereinafter. The invention accordingly comprises the apparatus possessing the features, properties and relation of elements as exemplified in the following detailed disclosure and the scope of the application of which will be indicated in the claims.
US Referenced Citations (1)
| Number |
Name |
Date |
Kind |
| 4350903 |
Rowen et al. |
Aug 1987 |
|
Continuation in Parts (1)
|
Number |
Date |
Country |
| Parent |
857739 |
Apr 1986 |
|
Patent Grant
4745351
