Radiant energy – Photocells; circuits and apparatus – Photocell controlled circuit
Patent
1998-04-06
2000-05-23
Westin, Edward P.
Radiant energy
Photocells; circuits and apparatus
Photocell controlled circuit
236 91C, H01J 4014, G05D 2300
Patent
active
060668431
ABSTRACT:
A thermostat for controlling the actuation of a heating, ventilation and air conditioning system includes a light discriminator that determines the occupancy of an occupancy space by sensing the presence of artificial light and adjusts the temperature set point of the thermostat accordingly. The light discriminator includes a photodetection device, such as a photodiode, that provides an output current that is proportional to the radiant flux of the ambient light of the occupancy space where it is mounted. A filter circuit cancels the undesirable frequency components of the output signal of the photodiode, such as the frequency components associated with sunlight. The filtered signal is therefore representative of the artificial light used to illuminate the occupancy space. A controller adjusts the temperature set point of the thermostat in response to the filtered signal.
REFERENCES:
patent: Re32450 (1987-06-01), Blake
patent: Re33205 (1990-04-01), Blake
patent: 3672268 (1972-06-01), Scheibel et al.
patent: 4041308 (1977-08-01), Fujita
patent: 4079388 (1978-03-01), Takahama et al.
patent: 4220412 (1980-09-01), Shroyer et al.
patent: 4464049 (1984-08-01), Schroeder
patent: 4758767 (1988-07-01), Blake
patent: 4858767 (1989-08-01), Myers et al.
patent: 5037198 (1991-08-01), Gaboury
patent: 5039850 (1991-08-01), Yamaguchi
patent: 5039853 (1991-08-01), Blake et al.
patent: 5055669 (1991-10-01), Blake et al.
patent: 5088645 (1992-02-01), Bell
patent: 5598000 (1997-01-01), Popat
patent: 5803358 (1998-09-01), Ruettiger
Kinnear Glenn T
Lightstat, Inc.
Westin Edward P.
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