Abstract: Power to an electrical device is controlled using a phase control that changes a cutoff phase of an alternating current (AC) electrical signal delivered to the electrical device. The power delivered to the electrical device is increased to an operational level using the phase control. A level of the power delivered to the electrical device is maintained at the operational level using an integral half cycle control that selectively removes a plurality of half cycles from the AC electrical signal delivered to the electrical device such that a plurality of remaining half cycles in the AC electrical signal delivered to the electrical device have a frequency outside a range of sub-harmonic frequencies.

Abstract: What is described is a system for estimating a ripple component of an input signal. The system includes a first module configured to remove a direct current (DC) component from the input signal and output an alternating current (AC) signal that includes the ripple component and a low frequency component of the input signal. The system also includes a second module configured to determine a period and an amplitude of the AC signal and output an estimated ripple signal based on the period and the amplitude of the AC signal.

Abstract: A method of operating a memory system, including a memory controller which controls at least one memory device included in the memory system, is disclosed. The method includes: comparing a temperature of at least one memory device included in the memory system with a reference temperature; conducting a heating operation on the at least one memory device in order to increase the temperature of the at least one memory device, based on the result of the comparing step; and controlling the operation on the at least one memory device until it is determined that the temperature of the at least one memory device is equal to or greater than the reference temperature.

Abstract: A semiconductor device for measuring IR radiation is disclosed. It comprises a substrate and a cap enclosing a cavity, a sensor pixel in the cavity, comprising a first absorber for receiving said IR radiation, a first heater, first temperature measurement means for measuring a first temperature; a reference pixel in the same cavity, comprising a second absorber shielded from said IR radiation, a second heater, and second temperature measurement means for measuring a second temperature; a control circuit for applying a first/second power to the first/second heater such that the first temperature equals the second temperature; and an output circuit for generating an output signal indicative of the IR radiation based on a difference between the first and second power.

Abstract: Provided are a device and method and an electronic device for temperature control, which are used to solve the problem that electronic devices and components cannot operate in a low-temperature state. The temperature control device includes a temperature detection unit (10) configured to detect the operating temperature of a component (16); a heating unit (12) configured to heat the component (16) according to the detection result of the temperature detection unit (10) so that the operating temperature is between a first temperature and a second temperature; and a power supply interface (14) respectively connected to the temperature detection unit (10) and the heating unit (12) and configured to supply power to the temperature detection unit (10) and the heating unit (12). The first temperature is the lower limit value of the operating temperature of the component (16), and the second temperature is the upper limit value of the operating temperature of the component (16).

Abstract: A two-wire load control device (such as, a dimmer switch or an electronic switch) for controlling power delivered from an AC power source to an electrical load includes a thyristor for controlling the power to the load, a gate coupling circuit electrically coupled to a gate terminal of the thyristor, a control circuit configured to control the thyristor to turn the load on or off, and a power supply configured to conduct current through the electrical load to generate a supply voltage across a capacitor when the thyristor is non-conductive. When the electrical lead is on, the control circuit is configured to maintain the thyristor non-conductive after a beginning of each half-cycle until the magnitude of the supply voltage exceeds a predetermined threshold.

Abstract: A control circuit for reducing Total Harmonic Distortion (THD) in the power supply to an electric load, includes an input stage (10) for receiving a network voltage (V1) and providing a corresponding rectified sinusoidal output supply voltage (Vbus); an output stage (20) associated with the input stage (10) for providing power supply to an electric load (L); a control module (30) designed to control the power factor and the harmonic distortion (THD) of the energy obtained from the network voltage (V1), by regulating a pulse current (S1) that acts upon the power supply absorbed by the output stage (20); a regulating module (40) which is designed to: sense a main signal (SW) representative of the supply voltage (Vbus); compare the main signal (SW) with a preset reference (Vref); generate a regulating signal (S3) designed for the control module (30). The control module (30) is designed to modify the pulse current (S1) according to the regulating signal (S3).

Abstract: A method of queuing access to a power supply shared by a set of electrical access points. The access points turn on independently from one another and thus have independent power draws. Each access point has a specific power draw when on. The on state and associated power draw of each of access point is identified, and a load duration curve for each access point is normalized (i.e., combined with load duration curve(s)) from the other access points) into a probability distribution function. The probability distribution function is a normalized load duration curve that thus accounts for a varying set of “operating states” that may occur with respect to the set of access points (when viewed collectively). Each operating state has an associated probability of occurrence. As the operating state of the set (of access points) changes, access to the power supply is selectively queued, or de-queued (if previously queued).

Abstract: A power detection regulation device including a power detection signal generator, a power state detector and a regulated output unit is disclosed. The power detection signal generator receives the input power from an external power supply and generates a power detection signal. The power state detector generates a power state signal based on the power state derived from the power detection signal. The regulated output unit receives the power state signal and generates a driving signal to an external electrical device in accordance with the feedback signal from the external electrical device. The power state signal is provided for the external electrical element to perform relevant processes, and the regulated output device can output the predetermined driving signal on receiving the power state signal indicating some abnormal situation in the input power so as to maintain the normal operation performed by the actuating element in the external electrical device.

Abstract: A method of queuing access to a power supply shared by a set of electrical access points. The access points turn on independently from one another and thus have independent power draws. Each access point has a specific power draw when on. The on state and associated power draw of each of access point is identified, and a load duration curve for each access point is normalized (i.e., combined with load duration curve(s)) from the other access points) into a probability distribution function. The probability distribution function is a normalized load duration curve that thus accounts for a varying set of “operating states” that may occur with respect to the set of access points (when viewed collectively). Each operating state has an associated probability of occurrence. As the operating state of the set (of access points) changes, access to the power supply is selectively queued, or de-queued (if previously queued).

Abstract: A semiconductor integrated circuit includes a measurement circuit configured to detect a measuring quantity dependent on temperature, and a heating circuit configured to generate heat in response to a detection, by the measurement circuit, of the measuring quantity indicating that the temperature is lower than a predetermined level.

Abstract: A power supply unit is provided. The power supply unit comprises a capacitor, a power input unit supplying power to the capacitor, a temperature sensor which is incorporated into the capacitor and senses a temperature of the capacitor, and a power control unit controlling a power path supplying power from the power input unit to the capacitor based on the sensed result of the temperature sensor. The power supply unit can be used continuously by shutting off a supply of power to protect an internal circuit of a capacitor in case of the abrupt increase in internal temperature of the capacitor.

Abstract: A heating system including a power supply and a heating element for conducting a current from the power supply. A temperature sensing device is adopted to detect a temperature of the heating element, and a switch is connected in a circuit containing the power supply and the heating element to switch the current on or off. Further, a microprocessor produces a pulse-width-modulated signal as a function of the detected temperature, where the pulse-width-modulated signal drives the switch.

Abstract: An electric blanket includes a heating element extending through the blanket so that, upon receiving electric current from a power source, the element heats the blanket. A regulator circuit is connected to the element. It is configured to measure the resistance of the element and to control delivery of the electric current from the power source to the element responsively to the resistance so that the element heats to a desired temperature.

Abstract: An improved control method is provided that combines conventional ON-OFF control and conventional phase-angle control to reduce the AC inrush current to an electrical load, such as a tungsten halogen lamp used as a heating element in a laser printer, so that the power control circuit can satisfy both the European flicker and European harmonic requirements. Phase-angle control is applied to the load for a very short time period when it is initially energized, then the control circuit quickly switches from phase-angle control to standard ON-OFF control to reduce the harmonics generated by conventional phase-angle control methodologies. The electrical load exhibits three possible states: power full OFF, power ramp-up, and power full ON. During the power ramp-up state, power supplied to the load is adjusted by delaying the phase angle of the firing pulse relative to the start of each AC half cycle.

Abstract: A control device includes both a heating element and a temperature sensor. The control device has the form of a Wheatstone bridge which applies sensing current to the heating element. When the bridge is unbalanced, the control device may apply heating current to the heating element. In one embodiment, the sensing current is switched, so that it flows only for a relatively small part of the electrical cycle. The circuit also includes a provision for reduction or elimination of electrical spikes. The circuit further includes a calibration arrangement, which enables the user to adjust the bridge without passing heating current through the heating element. Another feature of the invention enables the set point of the bridge to be remotely controlled, by adjusting a level of analog current applied to the bridge. The circuit also includes an arrangement for compensating for temperature-induced changes in its components.

Abstract: In a method for controlling the actual temperature of an intermittently operated heating means, at least one operating parameter is measured for a predetermined measuring time period (T) during a switch-on interval (86) of the heating means. On the basis of the measured value of the at least one operating parameter, the actual temperature of the heating element is detected. The length of the current switch-on interval (86) is changed in dependence on the result of a comparison between the actual temperature and a predetermined desired temperature. The minimum length of each switch-on interval (86) is equal to the measuring time period (T). The measuring time period (T) is selected to provide that, during the length of the measuring time period (T), the thermal energy supplied to the heating means is less than the thermal energy emitted during the following switch-off interval (88) extending up to the next switch-on interval (86).

Abstract: A power conservation circuit having a low voltage power supply for powering a first and second switch. The first switch connects output terminals to either the low voltage power supply or a powered device. The second switch connects or disconnects power to the powered device. The low voltage power supply provides a sensing current when a load is placed across the output terminals. The current goes to a control switch which causes the first and second switches to switch into the ON state. A sensing circuit detects the continued draw of current from the powered device while a load is present. The sensing circuit maintains the control switch in the ON state. In the absence of any loads on the output terminals, the sensing circuit causes the control switch to switch the first and second switches into the OFF state. In the OFF state, power is disconnected from the powered device thereby conserving power when there is no load requesting the use of the powered device.

Abstract: A control system is provided for controlling the average power from an alternating voltage source (AC) to a load having inductive properties. The system uses a synchronous switch shunted by a capacitor connected between the source (generator) and sink (load) to pulse duration modulate the AC voltage carrier wave. A control signal generator circuit drives the synchronous switch such that the switch is closed at a variable time early in each half-wave of the AC voltage source carrier wave and such that the switch is opened at a subsequent later, variable time during that half-wave. This is accomplished by sensing the voltage across the synchronous switch in order to inhibit closing of the switch early in the half-wave until the synchronous switch voltage (and thus the voltage on the capacitor) is substantially zero and then opening the synchronous switch at a point in time to give the desired volt-second area between closure and opening within each half-wave.

Abstract: The present invention is an apparatus for controlling a water delivery system utilizing an instant flow tankless water heater. It includes a programmable microprocessor with support circuitry to achieve control of the outlet temperature of a varying flow rate and varying inlet temperature stream. The system senses a water outlet temperature and controls AC power through an on/off mechanism to regulate power to heating elements embedded in the water stream. The capabilities of the heating elements are improved through the application of using a microprocessor to perform a proportional (P), integrating (I) and derivative (D) calculation. The calculations are used to determine the operating characteristics of the heating system and to control the heating system.

Abstract: A circuit for operating relay contacts is based upon the utilization of an AC line zero voltage to provide a relay contact closure. The circuit is inexpensive and draws extremely low current levels. The circuit involves a latching arrangement of gates responsive to a zero crossing detector and a Delay Time output from a sensor. The gating circuits function in a latching arrangement which has an adjustable output to energize a relay and in turn provide for the closing of contacts which occurs substantially at zero voltage.

Abstract: An improved temperature control circuit having a controller portion with an inhibit input and a temperature responsive circuit portion that includes a resistive portion connected in series with a sensor portion which establishes the control point for the control circuit, the improvement including a semiconductor switch in series with the sensor portion, the semiconductor switch having two electrodes between which a resistor is connected. The resistor is also connected to the inhibit input of the controller to present a signal to inhibit operation of the temperature control circuit when the sensor portion and semiconductor switch is not conducting.

Abstract: An electronic controller comprising two input terminals between which an AC line and an electrical load are connected in series. A processing unit generates a command signal to control the supply of electrical power to the electrical load which closes an electronic switch also connected between the two input terminals for connecting the AC line and the load in series in a closed loop. A power supply voltage of the controller is provided by a second power supply derived from the two input terminals, consequently from the AC line through the load when the switch is open. When the command signal is generated, an electronic circuit opens the switch which is normally closed by this command signal to maintain the power supply voltage of the controller according to an adequate standard of operation. To energize the controller, the opening of the switch is activated in a temporary and repetitive manner for a certain whole number of cycles of the sector.

Abstract: A relay control for a cooking appliance having a heating element includes a sensor for detecting the occurrence of an arc upon a change of state of a relay coupled between the heating element and a power supply. Upon detecting an arc, the sensor provides a timing signal which is coupled to a microprocessor that controls the energization and deenergization of the relay. The microprocessor is responsive to the timing signal from the sensor to determine the time delay between the last energization/deenergization of the relay and the changing of the relay's state. From the time delay, the microprocessor determines a delay constant. Subsequently, the microprocessor energizes the relay at a time after the detection of a zero crossover point of the power supply signal, wherein the time is equal to the determined delay constant to cause the relay to change state at or slightly before a zero crossover point of the power supply signal.

Abstract: An apparatus for controlling a heating element for heating a substance in accordance with a maximum power which is to be applied to the heating element and in accordance with a selected temperature to which the substance is to be heated is used in combination with a temperature sensing probe for sensing the temperature of the substance heated by the heating element. The apparatus includes first circuitry for generating a first control signal which is a function of the difference between the selected temperature and the sensed temperature and second circuitry for generating a second control signal which is a function of the maximum power.

Abstract: The combination of a heating element and a control unit therefor and methods of making and of operating the same are provided, the heating element normally being adapted to be operated by the continuous full wave pulses of a certain high voltage alternating current source and the control unit being operatively interconnected to the heating element for operatively interconnecting the heating element to a high voltage alternating current source, the control unit having an arrangement for operating the heating element with a certain repeating pattern of skipped full half-wave pulses of the source when the source has a higher voltage than the certain source.

Abstract: A humidifier boiler has a plurality of electrodes supplied with electric current through circuitry which includes at least one solid state switch or relay such as inverse parallel thyristors or triacs arranged to switch at zero voltage so that, when the humidifier is called upon to vary the quantity of water vapor output from the boiler through an outlet pipe in response to a control signal from a humidity controller, the control signal causes the duration of the "on" and/or "off" periods of the, or each, solid state switch or relay to be varied in order to vary the power to the electrodes.

Abstract: The combination of a heating element and a control unit therefor and methods of making and of operating the same are provided, the heating element normally being adapted to be operated by the continuous full wave pulses of a certain high voltage alternating current source and the control unit being operatively interconnected to the heating element for operatively interconnecting the heating element to a high voltage alternating current source, the control unit having an arrangement for operating the heating element with a certain repeating pattern of skipped full half-wave pulses of the source when the source has a higher voltage than the certain source.

Abstract: An automatically controlled recirculating high velocity hot air sterilization device includes a housing having a sterilization chamber with a temperature sensor mounted therein, a hot air plenum including a blower in fluid communication with a heating element and sterilization chamber for inputting hor air into and receiving hot air from the sterilization chamber for recirculation, and a control chamber having a temperature sensing circuit connected to the temperature circuit for producing electrical inputs representative of the sterilization chamber temperature, power circuits connected to the heating element and blower, a controller connected to the temperature sensing circuit for monitoring the temperature, and to the heating element and blower circuits for controlling their operation, and a control panel including cycle selection switches for operation, an on/off switch, and temperature and timer/error displays.

Abstract: A fabric press comprises a press with a heating element (1) a temperature sensor (17), and a microprocessor based controller programmed to apply electrical power initially to the element for a boost period during which the press temperature is limited to a boost temperature, and then at the end of the boost period, to reduce the applied power and thereafter to control the power to maintain the press temperature substantially at a lower normal temperature. The controller comprises microprocessor (14) which supplied signals to a triac (12), the signals being timed to be applied at the zeros of the a.c. supply voltage and to switch the heater power for complete cycles of the supply voltage.

Abstract: A hot melt adhesive applicator operable at a number of selected temperatures having a portion of the circuitry for control of the applicator temperature at a point remote from the applicator body. The remotely located circuitry employs a differential amplifier and a zero crossing detector for controlling the operation of a triac which, when turned on, increases the temperature at the applicator. The operational amplifier is protected by a clamping circuit from receiving a signal, when a temperature setting is changed from a high to a low setting, that would otherwise cause the differential amplifier to provide an output required for turning on the triac which would cause a run away condition to exist.

Abstract: An AC power control apparatus includes a plurality of power supply circuits for generating powers having different maximum values, a switching circuit for, after an AC current is continuously set in a desired turn on control state, alternately selecting a first power supply circuit used until that time and a second power supply circuit for supplying a power approximating a power supplied to a load at that time from the plurality of power supply circuits, a turn on time control circuit for gradually shortening a turn on time of the first power supply circuit while gradually prolonging a turn on time of the second power supply circuit until the turn on time of the second power supply circuit corresponds to the entire period, and a circuit for changing the turn on time of the power supply circuit in units of periods of the AC current.

Abstract: A heater including a sensing device for sensing an ambient temperature, a temperature input device for providing a user selectable input temperature both connected to a first circuit to control the heater. The first control circuit includes positive feedback and negative feedback to electrically define a temperature range. The first circuit provides an on/off time duty cycle output wherein the on to off time of the duty cycle is relative to the relationship between the temperature range and the sensed ambient temperature. A second circuit is connected to receive the duty cycle output from the first circuit and is further connected to an alternating current power source to provide a second output signal during the zero crossing of the alternating current power source and when the duty cycle output is present. A driver circuit is connected to receive this second signal and activates the heater when the second signal is active by providing a third signal to a triac which regulates power to the heater.

Abstract: A control system for controlling the supply of electrical power to a heating element associated with an electrical appliance such as a frypan. The application of power to the heating element is controlled in two distinct modes, a first mode for simmering and a second mode for cooking. The two modes are characterized by a control signal which exhibits control periods having a relatively short duration during the simmer mode and a relatively long duration during the cooking mode. The present invention also delays actuation of a switching element responsive to the control signal in order to compensate for inertial delays caused by the opening and closing of the switching element. The switching element is thus actuated at a time delayed from a zero crossover of an alternating current power supply by an amount corresponding to the opening or closing delay time associated with the switching element such that switching occurs at times which coincide with the zero crossover points of the alternating current power.

Abstract: A power control device for controlling power to a resistance heater in an oven uses a microprocessor, temperature measuring circuit, power measuring circuit, a triac circuit for firing the heater, a power phase synchronizer whereby the microprocessor synchronizes A.C. current signal and allows the triac to fire for a calculated portion of each phase of A.C. current to provide power to the heater such that the oven temperature is accurately controlled. A cooling device for cooling to subambient temperature such as -150.degree. C. also is provided. The power control device and oven are used in conjunction with instruments such as a dynamic mechanical analyzer so that physical data on test samples can be obtained over a wide temperature range.

Abstract: A temperature-responsive circuit, for operation with a load-control apparatus having a control input for adjusting the magnitude of power applied to a load from a source, uses: a sensor responsive to the temperature in the vicinity of the load-control apparatus; a subcircuit for converting the temperature sensed by the sensor to the magnitude of an electrical parameter; a subcircuit for providing a reference electrical parameter having a magnitude predeterminately selected to equal the magnitude of the electrical parameter at a maximum desired temperature T.sub.

Abstract: A regulator circuit for controlling the heat output of a heating element adapted to be switched on and off by a semiconductor switch energized by a zero crossing switch having cycle group control, whereby a sensor signal derived from the sensed temperature is supplied to the zero crossing switch. In order to avoid an overriding of the control or operating temperature in the heating phase and to improve the accuracy of the temperature control, a secondary control voltage is derived from the sensor voltage according to the rate of rise and drop of the sensor voltage which in the heat phase the switch-off of the heating element is reset to lower temperatures depending on the secondary control voltage and in the cooling phase the switch-on of the heating element is reset to higher temperatures depending on the secondary control voltage.

Abstract: A temperature controlled circuit including a thermistor located in one branch of a bridge circuit containing several resistors, an operational amplifier, all combined in such a manner that a resistor is inserted in parallel with the thermistor to lower its impedance. The branches of the bridge circuit are also arranged in such a way that three branches have a nominal resistance approximately equal to the resistance of the thermistor in parallel with its fixed resistance at room temperature, while the fourth leg on the branch in series with the parallel thermistor and resistance across the voltage source will have a resistance nominally in the range of one-third of the paralleled resistor and thermistor. The arrangement is such that most any thermistor can be utilized merely by changing its parallel resistance, and the operational amplifier will operate with the thermistor over a wide temperature range.

Abstract: A temperature control device for a fixing heat source of a copying machine includes circuits for supplying power to the fixing heat source in synchronism with the zero-cross point of an a.c. signal applied from an a.c. power source. The device functions to supply the full-wave current to the heat source until a first predetermined temperature is sensed by a temperature sensor, to supply the half-wave current to the heat source until a second predetermined temperature is then sensed, and to change the duty factor of the half-wave current after attainment of the second predetermined temperature, thereby maintaining constant the temperature of the heat source with high accuracy.

Abstract: A power controlling circuit for automatic temperature regulator or the like using a zero voltage switching control. Clocks are dispersed and selected, in accordance with control factor, from among the clocks synchronized with the load power supply when zero voltage is detected from the load side to perform the zero cross control of the energization to the load through the detection of the zero voltage from the load side thereby to drive the zero cross control by the selection clock. The current limit close to the phase control can be achieved without any production of the noises. Also, the power control can be achieved without any production of the noises and does not damage the resolution and response property.

Abstract: Apparatus for controlling the cycles of AC power supplied to a variable thermal load in response to analog signals representing the temperature of the load comprising means for quantizing the analog signals into digital signals and controlling the proportion of integral cycles of AC current blocked to those supplied to said load, while providing a uniform spacing in time of the integral cycles supplied, in accordance with said digital signals. Also means are provided for modifying said digital signals in response to a predetermined average current overload.

Abstract: A system comprising a heat generating load such as a heater, a power control element for directly or indirectly supplying current to the heat generating load, a temperature detecting circuit for producing an ON signal when the temperature of the heat generating load is lower than a set temperature and an OFF signal when the temperature is higher than the setting, and a control circuit for feeding an ON or OFF signal to the power control element in response to the ON or OFF signal from the temperature detecting circuit. The control circuit includes a failure detecting circuit for logically comparing the signal from the temperature detecting circuit with the terminal voltage across the power control element to produce output when the power control element is in conduction although the signal from the temperature detecting circuit is an OFF signal.

Abstract: An improved temperature control circuit having a controller portion with an inhibit input and a temperature responsive circuit portion that includes a resistive portion connected in series with a sensor portion which establishes the control point for the control circuit, the improvement including a semiconductor switch in series with the sensor portion, the semiconductor switch having two electrodes between which a resistor is connected. The resistor is also connected to the inhibit input of the controller to present a signal to inhibit operation of the temperature control circuit when the sensor portion and semiconductor switch is not conducting.