150results about "Temperature control using analogue comparing device" patented technology

A scroll-type machine is disclosed which is particularly well suited for use as a compressor in refrigeration and air conditioning systems and incorporates a unique arrangement for modulating the capacity thereof. In one group of embodiments the capacity of the scroll-type machine is modulated by relative axial movement between the scroll members so as to form a leakage path across the wrap tips and opposed end plates. In another group of embodiments, modulation is achieved by reducing the orbital radius of one of the scroll members to thereby form a leakage path across the flank surfaces of the wraps. In the second group, a plurality of pin members are moveable from a first and second positions. In a first position the plurality of pin members operably enable the scroll members to orbit and in a second position the pin members restrict the orbiting motion of the first scroll members. Both types of scroll separation may be accomplished in a time pulsed manner to thereby enable a full range of modulation with the duration of the loading and unloading periods being selected to maximize the efficiency of the overall system. A motor control arrangement is also disclosed which may be used with either of the modulation methods mentioned above to increase the efficiency of the motor during periods of reduced load. Additionally, either of the modulation arrangements mentioned above may be combined with a delayed suction form of capacity modulation with or without the motor control feature to thereby achieve better operating efficiency under certain conditions.

A fixing device includes a pair of rotating members, a heater, a detector, a calculator, a pulse width modulation circuit, and a controller. In at least one embodiment, the pair of rotating members is configured to fix a toner image on a recording medium. The heater is configured to heat at least one of the pair of rotating members to a process temperature when driven with an alternating current. The detector is configured to detect the process temperature. The calculator is configured to calculate an amount of heat to adjust the process temperature to a reference temperature. The pulse width modulation circuit is configured to generate a drive signal having a pulse width modulation cycle divided into first and second off times and an on time inserted therebetween. The controller is configured to control operation of the heater according to the drive signal.

A temperature control circuit includes a microprocessor, a protection module, a temperature detecting module, and a heating module. The temperature detecting module includes a thermistor and a first switch. The thermistor is operable to sense a temperature to turn on or off the first switch for outputting a detection signal to the microprocessor and the protection module. The protection module is operable to control the microprocessor to work or reset according to the detection signal. The heating module includes a heater and a second switch. The microprocessor controls the second switch to turn on or off for making the heater work or stop working according to the detection signal.