US3909681A - Driving circuit for printing electromagnet - Google Patents

Driving circuit for printing electromagnet Download PDF

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Publication number
US3909681A
US3909681A US525220A US52522074A US3909681A US 3909681 A US3909681 A US 3909681A US 525220 A US525220 A US 525220A US 52522074 A US52522074 A US 52522074A US 3909681 A US3909681 A US 3909681A
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United States
Prior art keywords
coil
switching means
circuit
current
signal
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Expired - Lifetime
Application number
US525220A
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English (en)
Inventor
Alfredo Campari
Giorgio Vigini
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Bull HN Information Systems Italia SpA
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Honeywell Information Systems Italia SpA
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/06—Electromagnets; Actuators including electromagnets
    • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
    • H01F7/18—Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings
    • H01F7/1883—Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings by steepening leading and trailing edges of magnetisation pulse, e.g. printer drivers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J9/00—Hammer-impression mechanisms
    • B41J9/44—Control for hammer-impression mechanisms

Definitions

  • This disclosure relates to a driving circuit for driving a coil of an electromagnet for the actuation of a hammer in a high speed impact printer of data handling systems, which driving circuit includes first switching means upstream of the coil, second switching means downstream of the coil, current sensing means for sensing current in the coil, a closed unidirectional current path including the second switching means, the coil in a diode, first control circuit means for actuating the first switching means in response to an input con trol signal, second control circuit means for switching on the second switching means in response to the first input control signal and for the entire duration of the input control signal, and a bistable device triggered by the current sensing means to assume one of two electrical states when the sensed current reaches a predetcrmincd value and to provide an output signal corresponding to that one state, the output signal being effective to switch off the first switching means even in the presence of the input control signal
  • Such driving circuits must fulfill particular requirements. Thus, they must provide fast magnetization of the electromagnet, they must have repeatability with a limited spread of the kinetic energy imparted to the printing hammer in the various and subsequent energi zations, as well as during the entire actuation time of the latter.
  • a. provides magnetomotive force sufficient for magnetic core saturation and which assures the appropriate attracting force
  • the driving circuit includes in series connection a first and a second current switch respectively upstream and downstream of the electromagnet winding or coil and a unidirectional short circuit path for the coil, in which path the second switch is included.
  • the invention further includes a current detector, a bistable circuit and a control circuit which opens the first switch when the current flowing in the coil reaches a preestablished value.
  • the circuit additionally includes a second current detector associated with the bistable circuit to detect current flowing through the first switch and to open it when such current exceeds a safety limit.
  • the circuit additionally includes a voltage detector to provide an indication of the voltage existing at a coil terminal, the voltage detector and the bistable circuit providing logical information which allows one to check the correct circuit operation and, in case of failure, to identify faults in the circuit components.
  • FIG. 1 is a block diagram of a driving circuit according to the invention. I
  • FIG. 2 shows a wiring schematic of a preferred embodiment of the driving circuit according to the invention.
  • FIG. 3 is a timing diagram of the operation of the circuit according to the inventiom Referring now to FIG. 1, the circuit according to the invention is shown in block diagram form.
  • the coil 1 of a printing'electromagnet is connected between a voltage source V and a reference point or ground, through two switches 2 and 3, preferably of the electronic type respectively placed upstream and downstream'of the coil, and. connected respectively to the winding terminals 4 and 5.
  • a diode 6 is connected between ground and terminal 4 and is conducting, in relation to the voltage supply, which by example has been chosen positive, from ground towards terminal 4.
  • a current detector 7 is interposed between switch 3 and ground and has an output which controls a bistable device 8.
  • the bistable device 8 has-a second control input in the form of an output 10 of a voltage detecting circuit 9, which provides a signal indicative of the voltage existing at terminal 5.
  • the bistable device 8 is set to a first electrical state
  • the bistable device 8 issues a signal which is applied to control circuit l1 and commands the opening of switch 2. At this point the currentflowing in the coil 1 continues to flow in the closed path formed by diode 6 and switch 3 and decreases at an exponential rate which depends on the time constant of the circuit.
  • the control signal applied to input 15 is removed and switch 3 is opened, the overvoltage due to the opening is detected at terminal 5 by-circuit 9 and bistable device 8 is reset. Thereafter, a new operating cycle of the electromagnet may start.
  • the electromagnet is energized by an initial voltage which may be chosen so high as tomagnetize and saturate the circuit in a very short time.
  • the driving circuit accordingto the invention provides a rational utilization of the energy supplied to the electromagnet.
  • the driving-circuit is controlled by a quantity (current) relatedto theimagnetization status of the coil, it is largely insensitive to changed in the voltage vSwitch 2 is now specifically disclosed as a transistor having an emitter connected to terminal 4 of coil 1.
  • collector of the trnasistor switch 2 is connected to a voltage source +V,, having a rather'high value (for instance 45-V),' through a resistor 116 which has a very.
  • Switch 3- is now specifically disclosed as a transistor having its collector connected to terminal 5 of coil 1 and its emitter connected to ground through a resistor 17 which has a very low value (for instance 02 G).
  • Control circuit 1 which controls transistor switch 2, comprisestransistors 23,24, pulse transformer 25 and certain resistors and diodes to be described hereinafter.
  • Transistor 24 has an emitter connected to ground, while itsbaseis connected to the input terminal through a diode 28, whose conducting direction is from the-input to the base. ln'addition, the base" of transistor 24' is connected toa second control terminal 31 through a resistor 30.
  • transistor 24 When, at least one ofthe'control terminals 15 and 31 is at a positive voltage, transistor 24 is conducting and its collector is'at voltage a very close to ground. Thus, transistor 23, the base of which is connected-to the collector'of'transis'tor 24, is off and no current flows in the primary winding of pulse transformer 25. When both the terminals 15 and 13 are at a'voltage close to'ground (or negative) transistor 24 isoff and transistor 23 is cond ucting. Therefore, transformer 25' is fed by avoltage pulse, which is transferred to the sec-" ondary winding and commands the switchingon of transistor switch 2. The size of transformer 25 is chosen so as to avoid saturation for the maximum fo'reseable duration of the control pulses. v
  • the collector current flowing through resistor 21 causes a'voltag'e drop'across the resistor, so'that the collector volt'age rises.
  • the base emitter junction of transistor switch 3 is forward biased to render the switch conductive.
  • Transistor switch'3 remains conductive for the entire duration of the control pulse;
  • Transistor 23 has itscollector connected to a suitable voltagesource V through the primary winding of the transformer 25 and a current limiting resistor 26.
  • the emitter of transistor 23 is connected to ground.
  • the terminals of the secondary winding of the transformer 25 are connected respectively to the base and Further, the probability of catastrophic failure is reto the emitter of switching transistor 2.
  • the base of Thevoltage drop produced by the current across the resistor 17 (which current, byneglecti'ng the negligible base current of transistor switch 3,'is also the current flowing in the coil) provides a voltage indication proportional to such current.
  • a Zener diode 32 connected in opposition to a diode 33,. provides a unidirectional short circuit path.
  • control circuit 12 which controls transistor switch 3 includes a transistor 18, for instance of PNP type,
  • a control terminal .15 is connected to the base of transistor18 through resistor 22.
  • the emitter of transistor l8 is connected to a voltage source V and the collector thereof is connected both to the base of transistor 103, through resistor 2 and to ground, throughresistor 21.
  • transistor switch 3 too is non-conductive.
  • the potential'of the latter approaches ground potential, so that the base-emitter junction of transistor 18 becomes forward biased and transistor 18 becomes conductive.
  • Control terminal 31 is driven by the bistable circuit 8.
  • thebistable circuit 8' includes an amplifier 34, a transistor 35 and certain diodes and resistors.
  • the inverting input of the amplifier 34 is connected to the emitter of transistor switch 3 through resistor 36 and receives a voltage signal proportional'to the current flowing in coil 1.
  • the noninverting input of the amplifier 34 is connected on one side to a voltage source +V through resistor 37 and on the other side to ground, through resistor 38.-ln addition the non-inverting input of amplifier 34 is connected to the output of the amplifier through resistor 39 and diode 40.
  • Diode 40 has a conductive direction from the input to the output of the amplifier.
  • transistor switch 3 When transistor switch 3 is open, the inverting input of amplifier 34 is at ground potential. Resistors'37 and 38 are chosen of a value so as to apply to the noninverting input a voltage that is slightly positive. The output of the amplifier 34 is therefore at a positive level and diode 40 is reverse biased.
  • the output of amplifier 34 is connected through resistor 41 to the base of transistor 35, whose collector is connected to the voltage source through resistor 43 and whose emitter is connected to, ground.
  • transistor 24 is kept in its conductive state and transistor 23 and transistor switch 2 are switched off. Therefore, as
  • Such voltage is sufficiently high to bring the potential of the non-inverting input to a potential higher than the one applied to the inverting input so that the output of the amplifier 34 becomes positive.
  • terminal 5 is connected to the voltage source V through diode 42 so that the self-induced voltage cannot exceed the value of voltage source V
  • the remainder of the driving circuit consists of protective devices. Maximum current protection is achieved by means of resistor 1 l6, transistor 48 and resistor 49.
  • Transistor 48 (of PNP type) has its emitter connected to the voltage source V and its collector connected to the inverting input of amplifier 34, through resistor 49. Its base is connected to the collector of transistor switch 2.
  • transistor 48 normally open, starts conducting and applies to the inverting input of the amplifier 34 a positive voltage which causes the intervention of bistable circuit 8 and the switching off of transistor switch 2.
  • a further device which provides indirect protection consists of a voltage detector connected to terminal 4 of the coil 1.
  • a voltage detector connected to terminal 4 of the coil 1.
  • Such a circuit may consist of a voltage dividerincluding resistors 50, 51 and a threshold circuit 52 having an input connectedto such voltage divider so asto provide an output signal of a first level when the input voltage is lower than, a threshold voltage, and an output signal of a second level when the input voltage is higher than the threshold voltage.
  • the threshold circuit 52, as well'as amplifier 34 are conventional circuits which are commerciallyavailable as integrated devices and therefore they need not be described in detail.
  • An output terminal E of the threshold device 52 provides'asignal which, jointly with the signal present at the collector of transistor 35 (terminal D), provides a heretofore unavailable degree of diagnostic power for detecting failures and for fast tion circuit. 7
  • FIG. 3 is a timing diagram showing the operation of the driving circuits and enables one to evidence the utility of signals present at terminals D, E.
  • the waveform designated by the reference numeral 15) represents the control voltage applied to input terminal 15.
  • theinput control signal is at a positive value, no current is flowing in the coil 1 and terminals and D are at' zero voltage.
  • the input control signal is lowered to zero level.
  • transistor switches 2 and 3 start conducting and current starts flowing in coil 1.
  • the signal at terminal E rises to a positive level.
  • the bistable circuit 8 is set and the signal at terminal-D'rises to a positive level. Therefore, transistor switch 2 is cntrolled to switch off, such action occurring with some delay at instant 1
  • the voltage at terminal 4 decreases and the signal at terminal E goes to zero level.
  • Transistor switch 3 steadily in off state. No current can flow in the coil 1: the bistable circuit 8 is not set and at instant t terminal D is still at electrical "levelzero. v
  • second control circuit means connected to said second switching means for switching on said second switching means in response to said input control signal and for the entire duration of said input control signal; a bistable deviceconnected to and triggered by said current sensing means to assume one of two electrical states when the sensed current reaches a preestablished value and to provide an output signal corresponding to said one state, said output signal being connected to said first control circuit means and effective to switch off said first switching means even in the presence of said-input control signal.
  • Driv.ing circuit as claimed in claim 1 further comprisingovervoltage detecting means to detect an overvoltage due to the switching off of said unidirectional current path and to provide an overvoltage signal, said overvoltage signal being applied to said bistable device, said bistable device being reset in that one of the electrical states other than said one by said overvoltage signal.
  • Driving circuit as claimed in claim 1 wherein there is a voltage detector connected to said coil between said coil and said first switching means.
  • said first control circuit means includes a transformer having a primary winding, and demagnetization means for said primary winding including means defining an unidirectional short circuit'path.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Impact Printers (AREA)
  • Protection Of Static Devices (AREA)
  • Electronic Switches (AREA)
US525220A 1973-11-28 1974-11-19 Driving circuit for printing electromagnet Expired - Lifetime US3909681A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT31771/73A IT1001996B (it) 1973-11-28 1973-11-28 Calcestruzzo incorporante dei corpi pieni oppure cavi a forma sferica c pseudo sferica in vetro

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JP (1) JPS5821405B2 (it)
IT (2) IT1001997B (it)

Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4032766A (en) * 1976-05-17 1977-06-28 Tally Corporation Wide range current flow fault detector
US4048665A (en) * 1974-12-20 1977-09-13 Honeywell Information Systems Italia Driver circuit for printer electromagnet
US4071874A (en) * 1976-06-28 1978-01-31 Xerox Corporation Hammer protection circuit
FR2398375A1 (fr) * 1977-07-20 1979-02-16 Lucas Industries Ltd Circuit d'excitation de solenoide
DE2847492A1 (de) * 1977-11-03 1979-05-10 Philips Nv Druckwerk mit stossvorrichtung und aufnehmer
US4167030A (en) * 1977-07-19 1979-09-04 Frankl & Kirchner Gmbh & Co. Kg Protective circuit for an electronic switching amplifier in series with an electromagnet
US4173030A (en) * 1978-05-17 1979-10-30 General Motors Corporation Fuel injector driver circuit
US4227230A (en) * 1978-09-19 1980-10-07 Texas Instruments Incorporated Switch mode driver
EP0017710A1 (de) * 1979-04-14 1980-10-29 Binder Magnete GmbH Schaltung zur Steuerung eines Impulsmagneten
EP0020975A1 (fr) * 1979-06-25 1981-01-07 International Business Machines Corporation Circuit de commande de l'application d'un courant à un enroulement et son application à un dispositif d'impression
EP0026068A1 (en) * 1979-09-22 1981-04-01 LUCAS INDUSTRIES public limited company Circuits for electromagnet energisation control
US4262592A (en) * 1978-04-06 1981-04-21 Ricoh Company, Ltd. Hammer drive apparatus for impact printer
US4266261A (en) * 1978-06-30 1981-05-05 Robert Bosch Gmbh Method and apparatus for operating an electromagnetic load, especially an injection valve in internal combustion engines
US4326234A (en) * 1980-06-06 1982-04-20 Westinghouse Electric Corp. Electrically held power relay circuit with reduced power dissipation
US4327394A (en) * 1978-02-27 1982-04-27 The Bendix Corporation Inductive load drive circuit utilizing a bi-level output comparator and a flip-flop to set three different levels of load current
US4344102A (en) * 1980-09-18 1982-08-10 Square D Company Anti-telegraph control circuit for electromagnet coil
EP0081374A1 (en) * 1981-12-09 1983-06-15 Sperry Corporation Pulse width modulated control circuit for double solenoid valve
EP0180060A1 (en) * 1984-10-31 1986-05-07 International Business Machines Corporation Self-timing and self-compensating print wire actuator driver
US4674897A (en) * 1985-08-26 1987-06-23 Dataproducts, Inc. Actuator for dot matrix printhead
US4706561A (en) * 1984-10-25 1987-11-17 Genicom Corporation Printing activator test circuit generating back EMF
FR2601811A1 (fr) * 1986-07-15 1988-01-22 Spinner Gmbh Elektrotech Circuit de commande pour la bobine excitatrice d'un electro-aimant
EP0288864A2 (en) * 1987-04-30 1988-11-02 BULL HN INFORMATION SYSTEMS ITALIA S.p.A. Control circuit for dot matrix printer head
EP0299267A2 (en) * 1987-07-14 1989-01-18 BULL HN INFORMATION SYSTEMS ITALIA S.p.A. Power recovery circuit
US4880322A (en) * 1987-11-20 1989-11-14 Ta Triumph-Adler Aktiengesellschaft Method for rebound damping of print hammer magnets in typewriters or similar office machines
US4897557A (en) * 1986-06-19 1990-01-30 Mannesmann Aktiengesellschaft Electronic control system, in particular for a printer
EP0409577A1 (en) * 1989-07-18 1991-01-23 Brother Kogyo Kabushiki Kaisha Solenoid controlling apparatus
EP0409576A1 (en) * 1989-07-18 1991-01-23 Brother Kogyo Kabushiki Kaisha Current controlling apparatus
DE4020836A1 (de) * 1990-06-29 1992-01-02 Kloeckner Humboldt Deutz Ag Steuervorrichtung fuer ein elektromagnetisches ventil
DE3152626C1 (de) * 1980-12-17 1993-04-29 Asea Brown Boveri Elektronische Schaltungsanordnungen zur Ansteuerung eines elektromagnetischen Bauelementes
GB2269950A (en) * 1992-08-22 1994-02-23 Rover Group Fuel injector controller with fault monitoring
JPH10231947A (ja) * 1997-02-19 1998-09-02 Tokico Ltd ソレノイドバルブの異常検出装置
EP0995997A1 (en) * 1998-04-28 2000-04-26 Mikuni Corporation Apparatus for detecting trouble with solenoid-operated device

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5319754U (it) * 1976-07-30 1978-02-20
JP2007027465A (ja) * 2005-07-19 2007-02-01 Aisin Seiki Co Ltd リニアソレノイドの駆動回路

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3205412A (en) * 1961-07-05 1965-09-07 Teletype Corp Selector magnet driver
US3206651A (en) * 1961-11-30 1965-09-14 Honeywell Inc Circuit controlling flow of current
US3235775A (en) * 1962-06-22 1966-02-15 Teletype Corp Selector magnet driver
US3549955A (en) * 1969-08-19 1970-12-22 T O Paine Drive circuit for minimizing power consumption in inductive load
US3582734A (en) * 1969-04-24 1971-06-01 Raytheon Co Coil driver with high voltage switch
US3859572A (en) * 1973-03-16 1975-01-07 Ibm Magnetic coil driver circuit

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3205412A (en) * 1961-07-05 1965-09-07 Teletype Corp Selector magnet driver
US3206651A (en) * 1961-11-30 1965-09-14 Honeywell Inc Circuit controlling flow of current
US3235775A (en) * 1962-06-22 1966-02-15 Teletype Corp Selector magnet driver
US3582734A (en) * 1969-04-24 1971-06-01 Raytheon Co Coil driver with high voltage switch
US3549955A (en) * 1969-08-19 1970-12-22 T O Paine Drive circuit for minimizing power consumption in inductive load
US3859572A (en) * 1973-03-16 1975-01-07 Ibm Magnetic coil driver circuit

Cited By (42)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4048665A (en) * 1974-12-20 1977-09-13 Honeywell Information Systems Italia Driver circuit for printer electromagnet
US4032766A (en) * 1976-05-17 1977-06-28 Tally Corporation Wide range current flow fault detector
US4071874A (en) * 1976-06-28 1978-01-31 Xerox Corporation Hammer protection circuit
US4167030A (en) * 1977-07-19 1979-09-04 Frankl & Kirchner Gmbh & Co. Kg Protective circuit for an electronic switching amplifier in series with an electromagnet
FR2398375A1 (fr) * 1977-07-20 1979-02-16 Lucas Industries Ltd Circuit d'excitation de solenoide
US4314305A (en) * 1977-07-20 1982-02-02 Lucas Industries Limited Solenoid drive circuits
DE2847492A1 (de) * 1977-11-03 1979-05-10 Philips Nv Druckwerk mit stossvorrichtung und aufnehmer
US4192230A (en) * 1977-11-03 1980-03-11 U.S. Philips Corporation Printer, provided with an impact device comprising a transducer
US4327394A (en) * 1978-02-27 1982-04-27 The Bendix Corporation Inductive load drive circuit utilizing a bi-level output comparator and a flip-flop to set three different levels of load current
US4262592A (en) * 1978-04-06 1981-04-21 Ricoh Company, Ltd. Hammer drive apparatus for impact printer
US4173030A (en) * 1978-05-17 1979-10-30 General Motors Corporation Fuel injector driver circuit
US4266261A (en) * 1978-06-30 1981-05-05 Robert Bosch Gmbh Method and apparatus for operating an electromagnetic load, especially an injection valve in internal combustion engines
US4227230A (en) * 1978-09-19 1980-10-07 Texas Instruments Incorporated Switch mode driver
EP0017710A1 (de) * 1979-04-14 1980-10-29 Binder Magnete GmbH Schaltung zur Steuerung eines Impulsmagneten
EP0020975A1 (fr) * 1979-06-25 1981-01-07 International Business Machines Corporation Circuit de commande de l'application d'un courant à un enroulement et son application à un dispositif d'impression
EP0026068A1 (en) * 1979-09-22 1981-04-01 LUCAS INDUSTRIES public limited company Circuits for electromagnet energisation control
US4326234A (en) * 1980-06-06 1982-04-20 Westinghouse Electric Corp. Electrically held power relay circuit with reduced power dissipation
US4344102A (en) * 1980-09-18 1982-08-10 Square D Company Anti-telegraph control circuit for electromagnet coil
DE3152626C1 (de) * 1980-12-17 1993-04-29 Asea Brown Boveri Elektronische Schaltungsanordnungen zur Ansteuerung eines elektromagnetischen Bauelementes
EP0081374A1 (en) * 1981-12-09 1983-06-15 Sperry Corporation Pulse width modulated control circuit for double solenoid valve
US4706561A (en) * 1984-10-25 1987-11-17 Genicom Corporation Printing activator test circuit generating back EMF
US4667117A (en) * 1984-10-31 1987-05-19 International Business Machines Corporation Self-timing and self-compensating print wire actuator driver
EP0180060A1 (en) * 1984-10-31 1986-05-07 International Business Machines Corporation Self-timing and self-compensating print wire actuator driver
US4674897A (en) * 1985-08-26 1987-06-23 Dataproducts, Inc. Actuator for dot matrix printhead
US4897557A (en) * 1986-06-19 1990-01-30 Mannesmann Aktiengesellschaft Electronic control system, in particular for a printer
FR2601811A1 (fr) * 1986-07-15 1988-01-22 Spinner Gmbh Elektrotech Circuit de commande pour la bobine excitatrice d'un electro-aimant
EP0288864A2 (en) * 1987-04-30 1988-11-02 BULL HN INFORMATION SYSTEMS ITALIA S.p.A. Control circuit for dot matrix printer head
EP0288864A3 (en) * 1987-04-30 1989-07-05 Bull Hn Information Systems Italia S.P.A. Control circuit for dot matrix printer head
EP0299267B1 (en) * 1987-07-14 1992-01-15 BULL HN INFORMATION SYSTEMS ITALIA S.p.A. Power recovery circuit
EP0299267A2 (en) * 1987-07-14 1989-01-18 BULL HN INFORMATION SYSTEMS ITALIA S.p.A. Power recovery circuit
US4880322A (en) * 1987-11-20 1989-11-14 Ta Triumph-Adler Aktiengesellschaft Method for rebound damping of print hammer magnets in typewriters or similar office machines
EP0409576A1 (en) * 1989-07-18 1991-01-23 Brother Kogyo Kabushiki Kaisha Current controlling apparatus
US5120143A (en) * 1989-07-18 1992-06-09 Brother Kogyo Kabushiki Kaisha Solenoid energization current controlling apparatus
US5120142A (en) * 1989-07-18 1992-06-09 Brother Kogyo Kabushiki Kaisha Solenoid controlling apparatus
EP0409577A1 (en) * 1989-07-18 1991-01-23 Brother Kogyo Kabushiki Kaisha Solenoid controlling apparatus
DE4020836A1 (de) * 1990-06-29 1992-01-02 Kloeckner Humboldt Deutz Ag Steuervorrichtung fuer ein elektromagnetisches ventil
GB2269950A (en) * 1992-08-22 1994-02-23 Rover Group Fuel injector controller with fault monitoring
JPH10231947A (ja) * 1997-02-19 1998-09-02 Tokico Ltd ソレノイドバルブの異常検出装置
US6147498A (en) * 1997-02-19 2000-11-14 Tokico Ltd. Device for detecting fault in solenoid valve
DE19806821C2 (de) * 1997-02-19 2001-06-13 Tokico Ltd Störungsfeststellungseinrichtung zur Feststellung einer Störung in einem Magnetventil
EP0995997A1 (en) * 1998-04-28 2000-04-26 Mikuni Corporation Apparatus for detecting trouble with solenoid-operated device
EP0995997A4 (en) * 1998-04-28 2004-07-21 Mikuni Kogyo Kk ERROR DETECTING DEVICE OF AN ELECTROMAGNETIC GESTEVERTED ARRANGEMENT

Also Published As

Publication number Publication date
JPS5086931A (it) 1975-07-12
IT1001996B (it) 1976-04-30
IT1001997B (it) 1976-04-30
JPS5821405B2 (ja) 1983-04-30

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