Communications: electrical – Systems – Call station
Patent
1974-06-26
1976-01-06
Caldwell, John W.
Communications: electrical
Systems
Call station
340233, 323 75E, 307252F, 99421TP, 99342, 73352, 317DIG6, G08B 2100, F24C 1500
Patent
active
039316203
ABSTRACT:
Solid-state circuitry is provided for an electrical thermometer for monitoring the interior temperature of food being cooked. A temperature sensing thermistor located in the tip of a probe, adapted to be partially inserted in food being cooked so as to monitor the interior temperature, is combined in circuit with a programmable unijunction transistor (PUT), used as a bridge threshold detector, an NPN transistor-diode load current switch and a buzzer alarm coil such that upon the reaching of a preset temperature within the food, the buzzer alarm is actuated. The self-heat of the thermistor probe provides a latching effect ensuring the continued firing of the PUT with the resultant smooth operation of the buzzer alarm. A resistor is combined in circuit to allow a slight back current to flow through the buzzer coil, thereby allowing the use of a buzzer alarm with a fairly non-critical air gap.
REFERENCES:
patent: 3594752 (1971-07-01), Alton
patent: 3778798 (1973-12-01), Heit
patent: 3815113 (1974-06-01), Welch
Doerr Ronald J.
Wellman, Jr. Carl E.
Caldwell John W.
General Electric Company
Wannisky William M.
LandOfFree
Temperature-responsive alarm control circuit does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Temperature-responsive alarm control circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Temperature-responsive alarm control circuit will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2352792