Abstract: In an electronic control device for electric ranges having a plurality of individual heat settings to selectively energize a heating element of the range under the control of a digital input to produce switching pulses having different on-off ratios, each heat setting has an associated time controlled constant power period in the start-cooking or roasting range, and in the subsequent finish-cooking range there are produced switch-on and switch-off pulses having a constant time pattern at every heat setting, while the time duration of the constant power period and the duration of the switch-on pulses in the finish-cooking range are different from one heat setting to another.

Abstract: An automatic heat control apparatus for use with an electric heating element in a kiln or the like comprises a first power controller having a plurality of on and off intervals. The first controller supplies electric current to the kiln heating element during its on intervals, and further includes means for adjusting the duration of the on intervals relative to the off intervals. A constant speed electric motor is mechanically coupled to the first power controller for gradually increasing the duration of the on intervals and decreasing the duration of the off intervals; such control ensures that the temperature inside the kiln increases very gradually to lessen the risk of breaking the ceramic material being fired. Furthermore, the average speed of the motor may be controlled by means of a second power controller, similar to the first controller, having a plurality of on and off intervals which intermittently energize the motor for rotation thereof.

Abstract: A switching means detects a malfunction due to an open circuited or broken state of a temperature sensing element. The switching means overrides a normal control by the temperature sensing element of a heater, so the heater is de-energized by the switching means and possible uncontrolled, dangerous activation of the heater is prevented.

Abstract: A control for selectively energizing a heater provided to raise the temperature of lubricating oil of a compressor employed in a refrigeration unit. The control includes a thermostatically operated switch provided to sense a temperature indicative of lubricating oil temperature. The switch connects the heater to a source of electrical energy when the sensed temperature falls below a predetermined value and the compressor is inoperable. When the compressor is operable, the heater is rendered inoperable irrespective of the sensed temperature.

Abstract: The glass pane of a vehicle window is provided on the surface of its central viewing area with a plurality of spaced, parallel linear heating resistors. First and second buses, disposed laterally of the central viewing area, extend transversely of the resistors and supply electric power to the resistors. A miniature transistorized control circuit mounted at a corner of the pane away from the central viewing area controls the supply of power to the buses. A plurality of moisture sensing, electrically conductive probes are provided on the pane at widely spaced zones and are connected to the input terminal means of the control circuit. Each probe includes a first portion coextensive in length with a resistor and running parallel thereto. One of the probes has a second portion parallel to and closely spaced from one of the buses. The control circuit responds to detection of fogging of the pane by anyone of the probes.

Abstract: A control for a resistance solder unit for maintaining solder probe temperature within an acceptable range is provided using a redundant interlocking switching circuit. A pair of dual, single pole, single throw, variable time delay electronic relays, and a pair of dual, single pole, single throw electrical relays may be interconnected into the supply line for the AC to DC soldering transformer to control the time and duration of current to a resistance soldering probe. Included may be an autotransformer-coupled feedback from the resistance solder ground return of the soldering probe. Typically, visual and audible signals provide probe power status.

Abstract: A sensor, located to respond to the temperature of the cooking platform and having a positive temperature coefficient of resistance throughout a range of temperatures up to the maximum selected safe operating temperature of the platform, is connected to a thermal cycling control switch and provides an increasing resistance with an increasing platform temperature to effect a wattage limiting control of the heating element supplying heat to the platform.