Abstract: A control system which minimizes the start up time of heaters and sustains long term automatic control is provided. This control system automatically converts control time constant current to constant power when the power reaches the power set and provides that after power interruptions, control will revert back to constant current until constant power control is again called for. The heater controlled by the control system of this invention is preferably a subterranean heater having a long heating element.

Abstract: An automatic electric maker for coffee or the like, having user selectable AUTO, BREW, WARM or OFF modes. The temperature of the WARM mode is selectable by applying partial power to the heating element. Full power can be triggered using a phase controlled triggerable semiconductor. Monitoring devices measure temperature and time to control the operator of the apparatus and to detect malfunction. A temperature comparator is provided to determine if the water conduit should be cleaned and to determine if the BREW state of the machine should be converted to the WARM state, and to place the system in the OFF state if necessary.

Abstract: A control system for processing products in conveyorized ovens. The system monitors and controls the oven temperature and monitors the velocity with which products are moved through the oven. At intervals, the system samples the oven temperature and determines the degree of product processing that has occurred in the sample interval. The system then adjusts the conveyor velocity as a function of the degree of product processing. The system can adjust the effective length of the sample interval as a function of the sensitivity of the product to changes in oven temperature and the difference between the oven set temperature and the actual oven temperature. The system integrates the effective time intervals to determine the total effective time that the product has been processed in the oven. The system is particularly suited to the cooking of food products such as pizzas.

Abstract: A fail-safe control system for operating a power relay to energize an electrical load such as a resistive heating element in a cooking apparatus includes first and second driving transistors connected in series with the control winding of the power relay and a source of power. A logic circuit, such as a microcomputer, produces pulses having specified characteristics at a single output port in order to energize the control winding. A circuit interconnecting the output port of the logic circuit with the driving transistors includes a first branch connected with the first transistor and a second branch connected with the second transistor. The first branch of the circuit includes an operational amplifier connected by a capacitor with the logic circuit output port in a manner that the first branch will drive the first transistor for a sufficiently long period of time initially in order to energize the relay control winding and cause the power relay to pull in.

Abstract: A time-based electrical appliance multi-mode control circuit and indicator arrangement which is connected to a power supply and an on and off switch. Upon turning the switch on, power is simultaneously supplied to the electrical appliance load and to a dual timer circuit. A first timer in the circuit is immediately energized causing a first indicator to represent an on state to the user. After a predetermined length of time, the first timer causes one output to go low, turning off the on state indicator and respectively turning on a ready state indicator. A second timer is then activated for a second predetermined period. At the end of the second period, the ready state indicator is turned off and the standby state indicator is turned on. At the same time, a triac connected to the electrical appliance load is turned off causing the power to the load to be automatically switched off.

Abstract: Circuit protection devices which comprise a PTC conductive polymer element and a second electrical component which is thermally coupled to the PTC element and which, when a fault causes the current in the circuit to become excessive, generates heat which is transferred to the PTC element, thus reducing the time taken to "trip" the PTC element. The second component is for example a voltage-dependent resistor which is connected in series with the PTC element under the fault conditions and is thus protected from damage. Alternatively, the second component is a thick film resistor which is connected in series with the PTC element.

Abstract: A temperature regulating control unit and method of making the same are provided, the unit comprising a RTD temperature sensor, a unit for applying electrical signals to the sensor, and a microcomputer for receiving digital signals from the sensor in relation to the temperature being sensed by the sensor, the unit for applying electrical signals to the sensor applying a varying voltage to the sensor.

Abstract: A control arrangement for an electric food heating device having heating elements for heating foodstuff and providing a source of light impinging on the foodstuff, the control arrangement comprising: a peaking circuit (42, 30) to determine maximum reflected light from the foodstuff and provide a first signal (VI), and measuring subsequently reflected light from the foodstuff and providing a second signal (V2), said peacking circuit including amplifier means (30) for determining the difference between the first and the second signals, and providing a third signal (V3); and a comparator means (26) for comparing the third signal (V3) and a preset signal (VB), the preset signal being proportionate to a desired heating level, the comparator means providing a terminating signal (DONE) to deactivate heating when the preset and the third signals are substantially equal.

Abstract: A multiplex heating system for measuring and regulating the temperature of a plurality of heating elements is disclosed. The heating system includes a plurality of heating elements, which also function as temperature sensing elements, that exhibit a known change in resistance as a function of temperature. The heating system further includes a power source, a control apparatus for regulating the respective heating power of each heating element, a measurement apparatus for measuring changes in resistance in the heating elements, and a plurality of switching arrangements. Each switching arrangement is coupled between one of the heating elements and, alternately, the control apparatus and the measurement apparatus, connecting the heating element to either the control apparatus or the measurement apparatus.

Abstract: A controller 3a for a Diesel engine, supplied with source voltage from a DC voltage source (battery) 1 and controlling the current supply to the glow plug 4a via a glow relay 6, includes, in addition to a microcomputer 13 and a reset circuit 14, etc., a source voltage step-up circuit 2. The source voltage step-up circuit 2 includes a source voltage detection circuit, and when the source voltage drops below a predetermined normal level, the circuit steps it up (i.e., raises it) to above the normal level. Thus, even when the engine is started at a low temperature and the source voltage falls below the normal level during the cranking of the engine, the glow plug 4a can be heated to a temperature at which the engine can be started.

Abstract: A microcomputer-based, closed-loop electronic temperature control system and method for an electrically heated cold weather garment having a plurality of independently heated zones. In one preferred embodiment the system comprises a potentiometer for selecting the desired temperature at which a plurality of areas of the garment are to be maintained, a thermistor for determining a reference temperature of the interior areas of the garment, and a plurality of conductive heating wires operable to heat each area of the garment independently. The system further includes a plurality of solid-state semiconductor power devices for controllably allowing current flow through each heating wire and, a plurality of current sensing circuits for sensing the current flow through each heating wire. The microcomputer receives information from the potentiometer, the thermistor and the current sensing circuits, and determines therefrom the level of heating required for each zone.

Abstract: A hot water heater control device and method for a building such as a home will allow the consumer user maximum savings with a modest investment by allowing the user to program into a control module a particular living cycle and assign a desired temperature to each of a predetermined number of heating start/stop times within the cycle. A structure exists for the user to program a desired high, medium, low and off temperature into a control module. Also, any one of several special condition modes may be activated as needed in order to provide maximum flexibility and savings.

Abstract: A temperature controller wherein breakage of a thermistor whose resistance decreases with increase in temperature of a member to be heated is detected by watching whether a voltage dependent upon the resistance of the thermistor is increased or not after a predetermined period of time. A heater for heating the member is turned off when the breakage of the thermistor is detected.

Abstract: Electrical power for an electrically heated vehicle windshield is controlled by an arrangement utilizing a modified alternator coupled to the windshield heater via an autotransformer. In a high power mode, the vehicle battery is coupled to a center tap of the alternator, while in a normal power mode the vehicle battery is coupled to a conventional rectified output of the alternator. A microprocessor controlled silicon controlled rectifier bridge provides direct current to the windshield heater element by rectifying the output of the autotransformer. Additionally, a current sensor coupled to the heater element is utilized by the microprocessor to determine the electrical resistance of the heater element in order to take required diagnostic measures.

Abstract: Power is controllably supplied to a resistive load. Power is passed from a power supply through a selectably operable switch directly to the resistive load and simultaneously to an energy storage device in parallel with the load. After a predetermined interval, the energy storage means causes the switch to open, thus causing the energy stored in the energy storage means to be transferred to the load. The switch is periodically closed according to a predetermined frequency.

Abstract: Disclosed is a device for and a method of applying output voltage from a power generator to a heating resistor in a motor vehicle. During the standstill condition of the vehicle the heating resistor is connected directly to the generator and a power supply network connected parallel to the terminals of a battery, is disconnected from the generator. The output voltage of the generator is regulated to increased values to achieve a higher efficiency in the heating resistor. During the travel of the motor vehicle, the heating resistor is connected in series with the power supply network and a regulated voltage from the power generator is applied across the series connection. The output voltage is regulated such that a nominal voltage is maintained at the power supply network. The switchover between the standstill and running operational conditions is provided by two switching devices which are controlled by a control device in dependency on operational conditions of the motor vehicle.

Abstract: This power adjustment device for electric power systems, in particular for electric power systems with electric ovens, has the aim of optimizing the electric absorption of the system by reorganizing the power requests of the various users comprised in the system. The device comprises elements for detecting the power requests of a plurality of users, a control and management unit adapted to check if the available power is sufficient to feed the requesting users and to enable and disable selectively some of the users operating at that moment according to the available power and according to criteria of priority or of elapsed operating time.

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 control device for controlling the heating capacity of the heating element of a cooking or heating plate, on which a cooking vessel, roasting vessel, or the like, can be placed and heated. The temperature on or in the cooking vessel is determined by means of a temperature sensor, conveyed to a logic circuit, and used in this for the control of the heating element by means of an output stage in dependence on the actual temperature determined and/or the temperature increase in the heating phase. In order for control of the heating output of the heating element to also be performed during a roasting process with a roasting pan placed on the cooking or heating plate, a program selection switch provided to select between various cooking processes, such as rapid simmering, steaming, warming and the like has a coordinated switching position for each and for a roasting process has an additional switching position.

Abstract: A temperature limiting device for connection across a common heater which senses the critical temperature of the heater to trip circuit breakers and thereby disrupt power to the heater when the critical temperature exceeds a predetermined value. The device includes an SCR or triac connected across power lines to the heater and which is triggered by a comparator monitoring the output of an integrator circuit. The input to integrator circuit is connected to the output of a thermocouple device. Upon the critical temperature of the heater exceeding the predetermined value as determined by the integrator and comparator circuits the SCR or triac is fired so as to short the voltage lines and thereby open the mechanically resettable circuit breakers.

Abstract: A temperature regulating control unit and method of making the same are provided, the unit comprising a RTD temperature sensor, a unit for applying electrical signals to the sensor, and a microcomputer for receiving digital signals from the sensor in relation to the temperature being sensed by the sensor, the unit for applying electrical signals to the sensor applying a varying voltage to the sensor.

Abstract: The present invention relates to controllable electric heaters, in particular heaters employing tungsten halogen lamps and suitable for use in cookers of the type having a ceramic hob below which are placed the heaters.It is an object of the present invention to provide a controllable electric heater employing two tungsten halogen lamps and other components of an inexpensive nature and which allows six different power settings to be obtained.

Abstract: An auxiliary control system for an oven or similar device that is separate from the primary control circuitry and operates independently when the condition occurs that could be hazardous or unsafe. The control acts to prevent the temperature of a known point to rise above a predetermined set point, or points, and the primary circuitry failed to take corrective action.

Abstract: A power-off control circuit for a household appliance, including a manually operating momentary switch having conductive and non-conductive states. The switch is connected to a source of electric power so when the switch is momentarily manually operated into the conductive state, power flows into the power-off control circuit. There is a power regulator connected to the manually operating switch for receiving the power during the conductive state and for converting the received power into a voltage. A timer is connected to the power regulator and when activated, initiates a predetermined time period in which the household appliance operates. The circuit also includes a relay connected to the timer and the source of electrical power so as to be in parallel with the manually operating switch. The relay operates in a conductive and non-conductive state and is in the non-conductive state until receiving a signal from the timer at which time the relay changes to the conductive state.

Abstract: A closed loop, electronic temperature control system for a tankless water heater. The control system incorporates error range comparison circuitry for comparing the difference between a water temperature selected from a temperature selection device and an actual water temperature sensed by a temperature sensing device. An error range comparison circuit operates to select a high gain when the sensed water temperature is within about +/-3.degree. Fahrenheit of the selected temperature, and a low gain when the sensed water temperature is more than +/-3.degree. Fahrenheit of the selected water temperature. A slow start network is included for applying current gradually to the heating element of the water heater when power is initially applied to the system. A master power down circuit quickly interrupts current flow to the heating element after the system has been powered down.

Abstract: The present invention relates to an image forming apparatus such as a copying machine and the like, and more in particular to the temperature control at a fixing unit thereof. In the image forming apparatus according to the present invention, the temperature of the fixing unit is controlled to be kept at the first set point by the first temperature control structure in normal operation, and when the temperature of the fixing unit comes to reach the second set point as a result of the first temperature control structure getting out of order, the temperature of the fixing unit is controlled to be kept at the second set point by the second temperature control structure. Consequently, the temperature of the fixing unit can be controlled to be kept within a desired range even when the first temperature control means gets out of order.

Abstract: A driving control apparatus for an electric range having a function of self-diagnosis by detecting a temperature within an oven with a voltage, detecting the present temperature within an oven by comparing the detected temperature with reference voltages according to each step, controlling precisely the temperature within the oven by the present temperature with an established temperature and determining automatically the state of a hardware for outputting the reference voltages at the time of detecting the present temperature. The apparatus can precisely control the temperature within the oven, and in case of an abnormal condition of a hardware, it stops the operation of heater and indicates the error, thereby the reliability and safety of the product can be enhanced.

Abstract: The present system includes a bridge circuit (with four legs) with one leg including a heating element. The mid-points of the bridge circuit are connected to a silicon controlled rectifier (SCR) which is further connected to the control element of a monostable multivibrator. Further connected to the power input elements of the monostable multivibrator is a D.C. power source. The monostable multivibrator is connected to a transistor which has a light emitting diode (LED) in its cathode circuit. The LED is part of a circuit which further includes a light sensitive triac. The light sensitive triac is further connected through a pulse generating circuit to the control element to a second triac which in turn is connected to supply heavy electrical current to the heating element.

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: A temperature regulating control unit and method of making the same are provided, the unit comprising a RTD temperature sensor, a unit for applying electrical signals to the sensor, and a microcomputer for receiving digital signals from the sensor in relation to the temperature being sensed by the sensor, the unit for applying electrical signals to the sensor applying a varying voltage to the sensor.

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 temperature controller utilizes a square wave signal whose pulse width is incrementally stepped in variable increments by a variable count in a register to determine the temperature being read by a sensor. The square wave signal is integrated to provide an analog signal that is compared to an analog signal provided by the sensor. When the amplitude of the integrated analog signal approaches the amplitude of the signal from the sensor, the count in the register is noted and the temperature is determined from the count by a piecewise linear equation. The temperature thus obtained is compared to a user selected temperature to control the temperature in the sensed area. The controller also includes a monitoring system that monitors the status of switching devices that are controlled by the controller to assure that the status of the switching devices corresponds to the status selected by the controller.

Abstract: A control system and method of operating the control system are provided, the system having a supervisory circuit for detecting failure of the system and disabling a high energy control circuit of the system, the supervisory circuit having a capacitor therein for sustaining an on condition of a supervisory transistor that is in series with an output relay driver transistor of the high energy control circuit, and a temperature sensing unit that is disposed intermediate a microcomputer of the system and the supervisory circuit for continuing the charging of the capacitor only as long as the temperature sensing unit is sensing an output temperature effect of a heating unit of the system that is below a predetermined high temperature limit for the system and that terminates the charging of the capacitor when the sensed temperature is above the predetermined high temperature limit.

Abstract: A control device for cooking apparatus includes an input panel for inputting a desired cooking condition. The input panel includes a flexible panel on which a plurality of cooking condition set key-patterns are formed in line. When a desired cooking condition set key-pattern is pressed, the input panel produces a voltage corresponding to the pressed key-pattern. The value of this voltage is changed step by step from one side key-pattern toward the other side key-pattern on the flexible panel.

Abstract: The invention relates to a control and switching apparatus for electric heating, comprising a micro-processor-based operation control unit (2) provided with control switches, and a regulating circuitry unit (5) associated with said control unit and comprising a plurality of regulating circuits. At least some of the regulating circuits are connectable to electronic sensors (8), whereby the combined effect of measuring messages fiven by said sensors, control data from the operation control unit (2) as well as set values (6) selected by the regulators provides the basis on which the regulating circuits (5) are adapted to control the ON/OFF-switches of electric loads, said switches being triac-switches (9a). One regulating circuit can be modified to operate as a regulating circuit suitable for controlling an electric sauna stove, said circuit being connectable, by means of a selector device, in power transposition with one or several other regulating circuits.

Abstract: A power control arrangement for controlling the power output of a plurality of resistive heating elements (9a, 9b) comprises a multi-position switch (S1, S2) for connecting the heating elements in series and in parallel, a zero voltage switch (4), AND-gate (5), clock pulse generator (6), shift register (7) and semiconductor device (8) such as a trail which cooperate to vary the duty cycle applied to the heating elements in both serial and parallel modes.

Abstract: A method of controlling a-c power by means of thyristors for resistive electric furnace for achieving a temperature control thereof, comprises providing an output which varies between O and N cycles in response to an input analog signal which also varies between 0 and 100% by a burn-on and -off control at zero crossings of an a-c power source. According to the invention, the output is uniformly distributed throughout a control period comprising N cycle times. The output pattern is transit to another output pattern in response to a new analog input signal at the desired point in time.

Abstract: A temperature regulating control unit and method of making the same are provided, the unit comprising a RTD temperature sensor, a unit for applying electrical signals to the sensor, and a microcomputer for receiving digital signals from the sensor in relation to the temperature being sensed by the sensor, the unit for applying electrical signals to the sensor applying a varying voltage to the sensor.

Abstract: A heating apparatus including a heating member for heating a subject, a temperature detector for detecting a temperature of the subject an energizing control element that is electrically connected to the temperature detector so that current conduction to the heating member at a the time when the temperature detector is actuated to operate after the subject to be heated and a switch element for disconnecting the temperature detector to the energizing control element in response to the actuation of the energizing control element. The heating apparatus is appropriate for use in a vacuum coffee maker.

Abstract: An apparatus for use in a crystal manufacturing system based on a floating zone method or Czochralski method, adapted to control a quantity relating to the diameter of a crystal rod at the crystallization boundary, and designed to reduce hunting in the control of the quantity relating to the crystal diameter so as to prevent disturbance in crystallization and reduce irregularities in the surface of the crystal rod even if there is a discrepancy between a predetermined pattern and the ideal pattern with respect to the quantity to be controlled.

Abstract: A low cost system for permitting the remote load management control of electrical residential room heating units that is compatible with existing heating systems of the type wherein each room heating element is controlled by a manually settable line voltage thermostat responsive to ambient room temperature. Included in the system is a normally closed low voltage operable thermal relay included immediately downstream of a resident circuit breaker and in the power transmission line for each room heating element and an associated single user programmable set back thermostat for shifting said thermal relays from normally closed to open position in response to residential dictated parameters of operation capable of also being operated in response to a remotely generated signal from a load management control center.

Abstract: A heating apparatus that utilizes a heating member for heating a desired subject detects the temperature of the subject being heated. This apparatus further generates a plurality of preset reference set points, compares these reference signals with the detected temperature. An energizing control circuit controls the supply of electricity to the heating member in accordance with the comparison result. The apparatus retains the signal generated from the comparison result, and as a result of this signal, changes the reference set point to cause the apparatus to heat at a new temperature setting.

Abstract: A combined electric sauna stove and sauna room heater having a plurality of electrical resistors and electrical circuitry for controlling the current supply to the resistors. In order to eliminate the need of separate room heating elements in the sauna room, the electric sauna stove is provided with a heating resistor for maintaining a normal room temperature in the room where the stove is located while the room is not used for bathing. This heating resistor may be a room heating resistor separate from the electrical resistors of the stove or it may be formed by connecting in series two or three of the electrical resistors of the stove.

Abstract: A control unit for a heating system such as a microwave oven comprises a RAM into which cooking programs of many menus are transferred from one of a plurality of available external memory modules. Data related to the cooking programs are displayed in a display window sequentially or in small units and the user can operate input keys to select a desired menu. The number of times each menu has been selected is stored and can be displayed.

Abstract: A temperature regulating control unit and method of making the same are provided, the unit comprising a RTD temperature sensor, a unit for applying electrical signals to the sensor, and a microcomputer for receiving digital signals from the sensor in relation to the temperature being sensed by the sensor, the unit for applying electrical signals to the sensor applying a varying voltage to the sensor.

Abstract: The present invention is directed to a heat treatment apparatus for performing heat treatment of a substrate. According to the present invention, a thermocouple is introduced into a heating furnace and discharged from the heating furnace by carrier means in such a state that one side ends of the wires forming thermocouple are connected to the substrate and another ends of the wires forming the thermocouple are connected to fixed terminals of a terminal mount. Movable terminals of a terminal driving mechanism are brought into contact with the fixed terminals of the terminal mount, to outwardly extract output signals of the thermocouple. Thus, temperatures of the temperature measuring substrate can be accurately measured while securing air-tightness in the heating furnace. Further, entanglement of metal wires forming the thermocouple is prevented in introduction/discharging of the substrate.

Abstract: An improved power control system for a household cooking appliance of the type having a glass ceramic cooking surface and at least one radiant heating unit disposed beneath the cooking surface operable at a plurality of user selectable power settings. At least one of the power settings has associated with it predetermined maximum and minimum reference temperatures defining a temperature band representative of the steady state temperature range for the glass ceramic support surface proximate the heating unit when heating normal loads at that power setting.

Abstract: A temperature control system for cooking apparatus, for example, a fryer using cooking oil or shortening which is heated by a suitable heating element. The cooking apparatus has different modes of operation including start-up mode, idle mode and cooking mode. Overshoot to a temperature above the setpoint temperature is limited during start-up mode, idle mode and cooking mode with the apparatus having different temperature control characteristics based on the mode of operation and adapting variable parameters to achieve optimum temperature control accuracy.

Abstract: This invention relates to controlling the simmering or cooking time in a cooking vessel which can be heated by means of an electrical cooking plate with a control circuit, in which the temperature in or on the cooking vessel is determined and utilized by the control circuit to regulate the heat output of the cooking plate, in which the simmering or cooking time can be set by means of an adjustable time element, in which the cooking plate can be shut off at a length of time bvefore the completion of the predetermined simmering or cooking time which is greater the slower that the rise of the temperature in the heating phase is, and in which, by using the heat content contained inthe cooking material after shutting off the cooking plate the simmering or cooking process is extended up to the preset simmering or cooking time.