Abstract: In a method for controlling an automatic door system, after a power-supply switch of the system is turned on, a door of the system initially conducts its low-speed opening/closing operation when a first human-body detection signal is inputted to the system; and then, when the door travels a distance more than a predetermined minimum door stroke, the door conducts its normal-speed opening/closing operation after completion of its traveling the predetermined minimum door stroke to enable the door to conduct its normal-speed operation within a short time after the power-supply switch is turned on.

Abstract: A self-contained switch unit for controlling a remote illuminating lamp has, in a common housing, a main ON/OFF switch, and has an emergency signal ON/OFF switch in a common housing, and has a visible pilot lamp. The main ON/OFF switch controls the ON or OFF mode of the illuminating lamp. The emergency signal ON/OFF switch functions, when the main ON/OFF switch is in the ON mode, to cause the controlled illuminating lamp to flash as a signal. When the controlled lamp is lighted, the pilot lamp is dark. When the controlled lamp is dark, the pilot lamp is lighted. When the controlled lamp is in the flashing mode, the pilot lamp also is in a flashing mode.

Abstract: A trimmable microminiature force-sensitive switching device for detecting the state of external conditions, such as pressure, acceleration and temperature, is disclosed. The device includes a silicon substrate having a reduced-thickness, deflectable member adapted to change its deflection in response to changes in the external condition to be detected. Increasing deflection of the member establishes electrical contact between a common contact and first one, then progressively more, spaced electrical contacts of a plurality of switches. Each of the spaced electrical contacts is connected to a common terminal. Trimming of the switching device is accomplished by application of a preselected external force, such as pressure, that causes the deflection of the deflectable member and the closing of one or more of the switches.

Abstract: A temperature sensitive control circuit for an electrically heated rotatable drum (11) including an internally disposed electric heater (27) and an electric temperature sensor (28) and, outside of the drum, an electric supply (30) for heating the heater and a D.C. supply (31) for producing a constant electric current through the sensor, wherein the electric connections with the drum occur through two sliding contacts (89, 90) only and a diode (29) bypasses the voltage of the heating supply around the temperature sensor. The heater current supply and the sensor current supply operate alternatively and the sensor measures drum temperature while the heater current is interrupted.

Abstract: A light responsive control and overload protection circuit for low voltage illumination systems includes means responsive to ambient light for providing an enabling output. Control means respond to the enabling output for switching heating current on when enabled. Heat-producing means is provided. The heating current passes through the heat-producing means whenever the control means is enabled. Heat-responsive circuit breaker means are in circuit between a low voltage power source and the load. The heat-producing means is thermally coupled to the heat-responsive circuit breaker means to transfer heat thereto and effect and maintain an opening thereof whenever sufficient ambient light is present. Heat-responsive means respond to heat from the heat-producing means to prevent the overheating thereof during overloads and load circuit short circuiting.

Abstract: A light sensitive switching circuit for automatically controlling the supply of electric power from a power source to a load, such as a lantern, is disclosed. When it becomes darker than a predetermined brightness the power supply starts and when it becomes bright again, the power supply is cut. The light sensitive switching circuit comprises first and second lines for connecting the power source and the load in series between the first and second lines. A first thyristor is connected between the first and second lines, and a second thyristor connected is to the first thyristor such that the anode of the second thyristor is connected to the gate of the first thyristor and the cathode of the second thyristor is connected to the cathode of the first thyristor. A photocell is connected between the gate and the cathode of the second thyristor.

Abstract: A system for automatically controlling lighting fixtures, appliances, an alarm, or the like in a room or enclosure has a pair of sensors installed in association with each entryway leading into a room. The sensors are triggered when a person passes through the entryway and send a signal to a logic circuit which is mounted in operative association with the sensors. The logic circuit distinguishes between entry or exit of persons from the room on the basis that in each entryway or door one of the two sensors is triggered first in case of entry, and the other one of the two sensors is triggered first in case of exit. The signals signalling entry are counted and stored in a first counting register separately from the signals signalling exit of persons from the room which are counted in a second counting register. The status of the first counting register storing the number of entries is continuously compared in a comparator circuit to the status of the second counting register storing the number of exits.

Abstract: The present invention provides a power supply for a digital light controller which is placed in a wall box where the neutral line cannot be used. The invention uses two separate and different kinds of power supplies that are placed in series with the load and the digital light controller depends on the power supply 1 when the load is off and on the second power supply when the load is on. The supplies are alternately switched when either the remote control or a manual switch is triggered. The first power supply uses a switch that is either opened or closed to develope a voltage drop of V or 0 and the second supply uses diodes back to back to develop a voltage drop which can be stepped up and rectified to a DC voltage for powering the digital light control.

Abstract: The invention relates to a thread movement sensor comprising an arm with at least one thread guide. The invention solves the problem of sensitivity of the sensor to the vibrations of the machine by making a part of the arm an element of a magnetic circuit of coil, the latter being connected to the control circuit of a knitting machine.

Abstract: The present invention teaches a control system wherein fiber optics controls the functioning of one or more types of wiring devices, such as a wall receptacle. With the use of the present invention, a relatively safer system is provided for use in wet, hospital, explosive and other environments, and which is capable of surface mounting. Switch and load supply assemblies are interconnected by fiber optic means for transmitting reflected signals from a movable mirror to a photocell-influenced relay circuit.

Abstract: The device includes an audio signal circuit having two separate terminals that are connected through the photoresistor elements of two, separate, optical isolators with an audio signal input/output terminal, so that signals can be routed selectively and bidirectionally along separate signal paths to or from the input/output terminal to one or both of the two separate terminals. A separate control circuit supplies DC power selectively to the LED's which control the selective energization of the photoresistor elements of the optical isolators, the advantage being that the photoresistive devices permit selective blocking of the audio signal paths without physically opening or interrupting the paths and thus avoiding objectionable signal spikes and consequent loud popping sounds in associated loud speaker systems. The DC control circuit includes two, manually operable double pole, double throw switches for controlling the selective routing of signals between the audio signal terminals.

Abstract: A sound actuated detector comprising a microphone, an elastic cylinder having a flexible bottom adapted to fit tightly around the microphone with the sensing surface of the microphone fitting tightly against the flexible bottom, a mounting base connected to the surface of the cylinder having the flexible bottom, an elastic isolating medium arranged between the base and the surrounding surface to which the detector is attached, and a weight connected to the microphone having a mass such as to eliminate movement of the microphone in response to frequencies above a selected frequency.

Abstract: The disclosure and drawings describe and illustrate a water mixer fitting having a temperature measuring means operatively coupled between the mixed water outlet opening and a display terminal disposed in or adjacent to the handle assembly.

Abstract: A fire prevention system useful for controlling actuation of equipment such as combustion or heating devices used in food preparation. The system according to this invention includes a fire alarm circuit and a timer circuit which automatically shuts down energy supplies to such equipment either in response to the detection of a fire, or during preselected periods of scheduled inoperation of the equipment. The system, therefore, in addition to operating as a fire alarm, reduces the likelihood that a fire will be started when equipment is unattended. The fire prevention system according to this invention further includes a manually operated override circuit which restores energy supplies to the controlled equipment irrespective of the control signals provided by the fire alarm circuit and timer.

Abstract: An electronic switch of the type having two external lines, one of which is connected to one pole of an operating voltage source in series with a load and the other of which is connected with the load. The switch comprises a sensor, e.g. an oscillator, responsive to proximity of an object thereto and has an output transistor operated by the sensor with blocking and conductive states selectively controlled by the transistor in response to the oscillator. A MOS-FET power transistor is in series with the output transistor and, to reduce the voltage drop in a conducting state of the electronic switch, a self-conducting MOS-FET is used as the MOS-FET power transistor.

Abstract: Disclosed is a touch control lamp system, including a touch control dimmer switch adapted to be plugged into a standard electrical household outlet, and a lamp having a male electrical plug adapted to plug into the touch control switch. When the plug from the lamp is plugged into the touch control switch, a touch control wire in the power cord of the lamp connects a conductive portion of the lamp to the touch control circuitry in the touch control switch, so that the lamp may be controlled by touching the conductive portion of the lamp. Moreover, a conventional lamp may be plugged into the touch control switch, which may be controlled by a touch control wire separately connected to the touch control switch.

Abstract: The present device includes a resistor network wherein the values of the resistors are chosen such that the heat generated by current passing through the resistors will be substantially equal to heat generated at a semiconductor junction which is to be cooled. The present device further includes a heat sink which is substantially identical to the heat sink employed to withdraw heat from the semiconductor junction to be cooled. Accordingly, the present device provides heat which is identical to the heat generated at the semiconductor junction and which heat remains ambient to the semiconductor junction to be cooled. The present device further includes a sensor which converts temperature to an electrical signal and which is located substantially in the center of the resistor network and at a distance from the heat sink that approximates the position of the semiconductor junction from its heat sink.

Abstract: An improved apparatus for switching off power to an electric load in the absence of the detection of movement from the doppler shift of a transmission signal. An oscillator generates an ultrasonic transmission frequency which is transmitted via a transmission plate coupled to the oscillator. A plurality of receivers detect reflections of the ultrasonic sound signal and supply the detected signal to a bandpass filter which passes the transmission frequency. A low-pass demodulator will detect any doppler signal which modulates the transmission signal and will supply it to an amplifier for amplification. The amplified signal is then provided to a narrow band filter which will pass only a narrow band of doppler-shift signals which correspond to the frequencies of human movement. The signal is then supplied to a switching means which, when activated, will discharge a first node. The first node is charged via a resistor and a capacitor coupled to a voltage source.

Abstract: A tamperproof noise alarm for use in a school classroom to detect noise exceeding a predetermined intensity and duration and, in turn, warn both teacher and students when excessive noise has been detected. The noise alarm aids the instructor in preventing excessive classroom noise which can and does disrupt and destroy a given learning situation. A sensitivity control is provided to allow the instructor to determine the noise level at which the alarm will automatically respond. Alarm circuitry is not enabled until a first excessive noise occurs. A closely spaced second excessive noise causes an audible alarm to sound. When switched to a "delay" mode, the noise alarm is more tolerant of occassional classrool noise and will not sound a warning unless additional noise occurs subsequent to a timed delay of several seconds.

Abstract: An electronic switch has a pair of light dependent resistors forming part of a potential divider with the hysteresis of the circuit being high enough to prevent equally applied changes in light level from effecting the switch action. The divider controls the voltage to an operational amplifier which is switched off by covering the other resistor. The switch may be combined with an opto-isolator or a relay to control power circuits.

Abstract: An electric switch for controlling a light has an infrared radiation detector. In response to a change in the radiation being sensed by the detector, the light is illuminated to a first brightness level. A manual switch is provided to turn on the light to a second brightness level.

Abstract: An ignition control device that utilizes a very sensitive flame rectification signal responsive circuit is disclosed. A printed wiring board arrangement is utilized with a careful arrangement of the conductive areas on the printed wiring board to substantially eliminate leakage paths that can provide a false indication of the presence of flame when none in fact is present.

Abstract: A sensing circuit system including circuitry for sensing impedance variations of a variable impedance element. As disclosed, a bridge circuit system includes a bridge circuit to which the variable impedance element is couplable. The bridge circuit system further includes circuitry for detecting open circuit or short circuit fault conditions of the variable impedance element. The variable impedance element is coupled to the bridge circuit by a connector, having two connector components, which is also operable to couple the fault detection circuitry to the bridge circuit only when the two components of the connector are connected together.

Abstract: The motion detector of the present invention, together with associated AC switching circuitry form a lighting control system which turns on room lights when the room is occupied, and extinguishes the lights when unoccupied. The detector sensitivity or threshold is adjusted in response to the previously detected conditions, providing reliable indication of both entry and continued presence in the controlled area, and producing few false alarms. The present embodiment of the invention has two threshold levels of detection, the higher level being used to detect initial entry into the room. After entry is detected, the motion detector lowers the threshold to detect the weaker signals usually occurring for continued presence in the area of the detector. When the occupant leaves the area, the motion detector threshold or sensitivity returns to the original value after a timeout period.

Abstract: A temperature controller with a remote sensor having a high temperature cutoff with circuit means to prevent operation of the unit if tampered with to bypass a safety function. A remote sensor has a thermal fuse and diode feeding a pulsating D.C. voltage to a control circuit having a capacitor and an impedance means to which pulsating D.C. is fed. If the sensor unit is bypassed the thermal fuse in the controller burns out to render the controller inoperative.

Abstract: A sound activated lamp arrangement includes a module having a threaded lamp bulb socket at one end and a bulb base at the other end for reception in a lamp socket of a conventional table lamp. A lamp bulb is received in the module socket, and a microphone is provided on the module. Circuitry within the module connects the module socket with the module base to thereby illuminate the lamp bulb in response to the reception of an acoustic signal from a smoke alarm device, burglar alarm, or other type of alarm device by the microphone. A photocell is provided on the module and is connected to the circuitry to sense ambient illumination. The circuitry is adapted such that the bulb is only illuminated when the photocell senses darkness. A push button switch is provided on the module for conventional operation of the lamp. A collar is received on the socket shell of the lamp to prevent operation of the lamp switch thereon.

Abstract: The presence of persons in a space is sensed with the aid of ultrasonic pulses which are sent out into the space when echoes of such ultrasonic pulses are received. Echoes attributable to the floor or to parts of a door in the space are timed out, and a remainder of such echoes is employed for sensing persons in the space. For example, sliding or revolving doors may be controlled and operated with the aid of such ultrasonic echoes, and limited access to secured areas may be provided thereby.

Abstract: A thermosensitive switching circuit includes a first voltage divider for producing a reference voltage with a predetermined constant level and a second voltage divider for producing a detection voltage signal whose level changes in response to changes in the temperature to be detected. The reference voltage is compared with the detection voltage signal by a voltage comparator having an open-collector type output circuit, and a feedback resistor is connected between the output terminal and the input terminal of the voltage compartor to provide hysteresis for the comparing operation of the voltage comparator.

Abstract: A reusable fast opening switch for transferring energy, in the form of a high power pulse, from an electromagnetic storage device such as an inductor into a load. The switch is efficient, compact, fast and reusable. The switch comprises a ferromagnetic semiconductor which undergoes a fast transition between conductive and insulating states at a critical temperature and which undergoes the transition without a phase change in its crystal structure. A semiconductor such as europium rich europhous oxide, which undergoes a conductor to insulator transition when it is joule heated from its conductor state, can be used to form the switch.

Abstract: In a digital data input circuit, a number of switches arranged in matrix of m rows by n columns (m, n: integer being equal to one or more) are operated in ON/OFF state and signals are obtained to represent setting state of the switches, amplifying means which are additionally connected before and after the switches are driven directly by power including ripple voltage generated by rectifying AC power, and pulse train signal for strobing output signal of the amplifier is generated from the power including the ripple voltage.

Abstract: The invention relates to an electrical device including at least one thermal battery, in which the electrolyte, which is normally inactivated, has to be activated by an activator, and whose temporary operation is coupled with a release of heat which subjects the elements of the battery to an increase in temperature such that to a specific temperature of said elements corresponds a predetermined moment in the operation of said battery.The device includes at least one thermal switch which is thermally connected with an element belonging to said battery, and which is designed to work at a predetermined temperature varying within the range of temperatures taken on by said element during operation of the battery.The invention finds an application in watching devices.

Abstract: A power controller for an electronic apparatus including an electrophotographic copying machine is provided for automatically prohibiting power supply to parts of the apparatus in response to the reduction of a light-shining amount, e.g., a decrease in the light surrounding the apparatus. The power controller includes a photosensitive element, a comparator, a delay circuit, a gate, and a relay. The photosensitive element serves to provide a voltage in accordance with the surrounding brightness.

Abstract: A device, for assuring selective commutation of one or the other of two electric measuring circuits to a single electric exploitation circuit as a function of the temperature gradient present between two distinct points of reference, has a first thermocouple placed at the first point of reference; a second thermocouple placed at a second point of reference, connected in opposition to the first thermocouple in order to deliver a differential electro-motive force (.DELTA.e) of which the value and the sign are a function of the value and sense of the gradient; and commutation means sensitive to this electro-motive force and fed solely by the energy produced by the two thermocouples. The commutation means includes a relay fed by the differential electro-motive force.

Abstract: A control circuit for protecting a metal oxide semiconductor field-effect power transistor from current overloads is disclosed in one embodiment of the control circuit. A silicon controlled rectifier is used to remove the bias voltage from the MOSFET in the event of a current overload. In another embodiment of the invention a bipolar transistor in combination with a second MOSFET is used to turn off the power MOSFET in the event of a current overload. The voltage appearing across the power MOSFET is used as an indication of a current overload condition.

Abstract: A portable, hand-held laser scanner system located within a compact housing. The housing includes a laser tube power supply means therefor and computer means. The laser is operative when triggered by the user to produce a laser beam which exits the housing to scan a target, such as a bar code symbol, located adjacent thereto and to receive light directed from the target. The computer is arranged for decoding the reflected signal. Communication means are provided within said housing to provide data output signals. The computer is arranged to control and override the operation of the laser when the amount of laser light produced within a predetermined period of time reaches a predetermined threshold value and for enabling the laser to operate when the amount of laser energy produced is less than the predetermined threshold value within the predetermined period of time.

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: An improved controller for an automatic seasonal adjusting solar powered light having a rechargeable battery, a solar array for charging the battery, and a lamp. A detector is connected to the solar array for activating a first timer, upon sunrise of a given day, to count down for approximately twenty-two hours and then, after countdown, for activating a second timer for turning the light on for approximately a two hour period just prior to the rising of the sun on the next given day. A third timer is activated upon the setting of the sun on the next given day to turn the lamp on for approximately four hours. The light is turned on only for a predetermined total amount of time during each given day even though the individual dawn and dusk times for the light being turned on can be selectively adjusted. A battery circuit is provided for deactivating the lamp activation circuit in the event of excessive drain on the battery or due to cloudy days.

Abstract: A microminiature switch for digitizing different-valued external conditions, such as pressure, temperature of acceleration, is disclosed. The switch includes a silicon wafer having a deflectable, reduced-thickness membrane adapted to move from a relaxed position toward increasingly flexed or bulged positions in response to greater-value changes in such external condition. Movement of the membrane from its relaxed position to more strained positions establishes electrical contact between a common terminal and first one and then progressively more switch-state terminals in the switch, wherein the number of switch states which are closed corresponds to the external condition acting on the switch.

Abstract: A detector is disclosed including a temperature sensitive amorphous magnetic alloy which shows a Curie point of not higher than 200.degree. C. and whose composition is represented by the formula:(M.sub.1-a Ni.sub.a).sub.100-z X.sub.zwherein M=Co or Fe; X=at least one of P, B, C and Si; 0.2.ltoreq.a.ltoreq.0.8 when M is Co, or 0.4.ltoreq.a.ltoreq.0.9 when M is Fe; and 15.ltoreq.z.ltoreq.30.

Abstract: Three distinct visual indications, one audible indication, and preferably one timing output voltage are provided which are individually activated depending upon when the sound levels falls within a predetermined level. This monitor aids both students and supervisors in establishing consistent and fair noise standards. Variable controls are provided to allow the supervisor to determine the sound level at which the visual indications and audible indication and timing output voltage will automatically be activated. A filter network is included that attenuates non-voice frequencies as well as short, non-repetitive sounds.

Abstract: A seismic actuation system incorporating a plurality of motion sensors. The motion sensors included a housing in which a weight is supported for slidable movement along a single direction within the housing. The sensors are mounted to a horizontally disposed enclosure. The sensors are arranged so that the directions of travel of the weights within the enclosures are uniformly arranged so that vibration of sufficient magnitude in the horizontal plane will cause one or more of the weights to move. By adjusting the mass of the weights, the sensitivity of the sensors can be adjusted. When a seismic event of sufficient magnitude occurs, the weight becomes displaced from a central position within its housing and moves to one or the other end of the housing to activate the contacts. Activating the contacts completes a circuit so that one or more warnings, such as bells, lights, or spoken words, are produced or one or more safety devices are actuated.

Abstract: An engine temperature sensor may be screwed into the engine block and is provided internally with electronic switch circuitry controlled by an NTC device. The sensor has external terminals for connecting to various temperature-related functions in the engine, such as an automatic choke, a petrol pre-heating device and an overheating indicator, and is capable of switching these functions on and off individually at the temperatures which have been pre-set for each function.

Abstract: The controller of the present invention regulates the flow of current through a resistive heating element by computing the predicted resistance R.sub.hot of the heating element at the desired temperature and then adjusting the voltage drop across and current flow through the resistive heating element until the relationship V=IR.sub.hot is satisfied. In an analog embodiment of the present invention, measurement of the voltage drop is obtained from a voltage amplifying circuit connected across the resistive heating element, while a measure of the current flow through the resistive heating element is obtained from a current amplifying circuit connected across a current measuring resistor in series with the resistive heating element. The output of the current amplifying circuit is multiplied by first and second variable gain amplifier circuits to produce a signal output representing the product of the current flow and the predicted resistance at the desired temperature.

Abstract: An electrical control system controls an electrical load device, particularly an inductive load such as the ballast of a gas discharge lamp which generates a back EMF when power is removed therefrom. The control system includes a first electronic switch for controlling the application of power to and withdrawal of power from the load and a second electronic switch which controls the first electronic switch. The second switch is responsive to a command signal preferably occurring between 90.degree. and 180.degree. of the AC power half wave to turn on and thus switch off the first switch which in turn withdraws power from the load. The circuit remains in this state until a predetermined circuit condition occurs at which point the potentials on the load and the AC power supply are at predetermined levels. The equal potential turns the second switch off, whereupon power is reapplied to the load by the first electronic switch.

Abstract: There is provided a control unit for controlling the operation of a fuel valve. The control unit includes a first relay and a second relay. The first relay and the second relay are connectable in series and oppositely actuable. The first relay is actuable in response to a first control signal. The second relay is actuable in response to a second control signal which is inverted with respect to the first control signal. Thus, the relays are differentially operated. Further, there is disclosed a scanner control unit which reduces the noise of a voltage signal whose magnitude is representative of the intensity of a monitored flame in a boiler. The flame scanner control unit uses a comparator to reduce the noise in the voltage signal. The voltage signal is provided at one input of the comparator and a reference signal is provided at the other input of the comparator. The reference signal is representative of the intensity of noise in the boiler when the monitored flame is out.

Abstract: A microprocessor controlled condition sensor comprising a parallel multiport microprocessor, precision resistor, capacitor, and one or more transducers (e.g., thermistor) determines the value of the condition being sensed (e.g. temperature) by calculating the resistance of the transducer through the ratio of interval 0/1 threshold timings determined by the RC time constants of precision resistor-capacitor and transducer-capacitor connections. The value of the condition (e.g., temperature) is subsequently obtained via a lookup table within the microprocessor which contains the relationship between transducer resistance and condition magnitude.

Abstract: A thermostat uses a source of a signal representing anticipation heat which is transmitted to a circuit to be combined with a signal from a temperature sensing element with a first time constant or delay when the thermostat is "ON", i.e., controlling a heat source to supply heat to a heat receiver and with a different time constant or delay when the thermostat is "OFF", i.e., controlling the heat source to interrupt the supply of heat to the heat receiver.

Abstract: A sound level alarm device sequentially listens to the sound level of an enclosure or area for a first predetermined interval of time, and thereafter does not listen to the sound level of the area for another predetermined interval of time. The circuit sounds an alarm upon detection of a sound level of a predetermined magnitude measured during the first time interval. The circuitry is designed for omitting quick, sharp noises such as a cough, hand clap, book dropping, or the like. The apparatus is advantageously used in class rooms, laboratories, libraries, and play rooms as a teaching aid wherein people with loud noisy habits are electronically assisted in overcoming these undesirable aspects of their life style.

Abstract: A sound actuated switch including a microphone coupled via an audio amplifier to a reset circuit. When a sound of sufficient intensity is received by the microphone a reset signal is supplied to the counter portion of an oscillator and counter circuit. The counter then begins counting oscillations and produces an "on" control signal until a predetermined count is reached, at which time an "off" control signal is produced. The control signal is supplied to the gate of a switching triac in a switch circuit. The presence of the on control signal causes the switching triac to electrically connect an AC power source to a load, typically a light. A simple, high efficiency DC power supply is also disclosed.

Abstract: An ignition equipment for light ignition thyristors for igniting a plurality of light ignition thyristors being connected in series with each other, which comprises an ignition circuit for generating a thyristor ignition electrical signal, a photoelectric conversion circuit receiving the thyristor ignition electrical signal to convert the same into a thyristor ignition light signal, a reverse voltage detecting means for detecting reverse voltage applied between an anode and cathode of each of the respective thyristors to transmit a reverse voltage detection signal, light guides for guiding the thyristor ignition light signal transmitted from the photoelectric conversion circuit to the thyristors, respectively, and light switches each inserted on the midway of each of the light guides and each interrupting the thyristor ignition light signal so as not to put the same into each of the thyristors while the reverse voltage is applied to each of the thyristors.