Patents Assigned to Hitachi Automotive Engineering Co.
  • Patent number: 4960092
    Abstract: An engine control system comprises a crank angle sensor for generating reference signals, each outputted at a first predetermined rotational angle interval of the engine and position signals for controlling the ignition timing, an angle ignition signal generator for generating an angle ignition signal on the basis of the reference signal and the position signal, a clock signal generator for generating clock signals with a constant time period, a time ignition signal generator for generating a time ignition signal on the basis of the reference signal and the clock signal, abnormality detector for detecting abnormality in the position signals and outputting selecting means for selecting to output the angle ignition signals in a normal state and the time ignition signals when the abnormality in the position signals is detected, whereby the ignition timing is controlled in both normal and abnormal states of the position signal.
    Type: Grant
    Filed: October 24, 1989
    Date of Patent: October 2, 1990
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Shoji Sasaki, Kenji Tabuchi
  • Patent number: 4944274
    Abstract: An air-fuel ratio control apparatus for an internal combustion engine includes a solid electrolyte having a first electrode disposed on one surface thereof to contact with the atmosphere and a second electrode disposed on the other surface thereof to contact with the exhaust gas from the engine through a diffusing resistor, and means for applying a voltage across the first and second electrodes to detect an oxygen pump current flowing in the solid electrolyte whereby a correction factor relating to a change in the diffusion coefficient of the diffusing resistor is computed so that the oxygen pump current detected by the detecting means is corrected in accordance with the correction factor and the air-fuel ratio of the exhaust gas is determined in accordance with the corrected oxygen pump current, thereby controlling the quantity of fuel supplied to the engine in accordance with the determined air-fuel ratio.
    Type: Grant
    Filed: October 4, 1989
    Date of Patent: July 31, 1990
    Assignees: Hitachi, Ltd, Hitachi Automotive Engineering Co.
    Inventors: Takayuki Itsuji, Sadayasu Ueno, Norio Ichikawa
  • Patent number: 4926960
    Abstract: An electric power steering apparatus for a vehicle comprises a steering shaft, an electric motor operable to generate an auxiliary steering force having a magnitude corresponding to a value of electric current supplied thereto, a steering toque sensor for detecting a steering torque applied to the steering shaft, a vehicle weight sensor for detecting a vehicle weight, and a control device. The control device is constituted to increase and decrease the value of electric current to be supplied to the electric motor in accordance with not only the increase and decrease of the value detected by the steering torque sensor but also the increase and decrease of the value detected by the vehicle weight sensor.
    Type: Grant
    Filed: September 16, 1988
    Date of Patent: May 22, 1990
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Hisatugu Ishikura, Kazuo Tahara, Toshimi Abukawa, Katsuji Marumoto, Toshiyuki Koterazaka, Mitsuyuki Hombu, Tadashi Takahashi, Hirohisa Yamamura, Toru Tatsuzaki, Tsutomu Ohmae, Shuichi Takamatsu
  • Patent number: 4922239
    Abstract: A multi-shade color liquid crystal display apparatus wherein a number of striped color liquid crystal elements are arranged in parallel in one direction. A color filter for each color liquid crystal element is arbitrarily selected to have one color and the ratios of the widths of the color filters to the pitches of the filters for each of a plurality of blocks of the striped color liquid crystal elements are made different from one another while maintaining one of the widths and pitches constant so that light and dark shades of the color are obtained in different blocks.
    Type: Grant
    Filed: January 28, 1988
    Date of Patent: May 1, 1990
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Masaru Kugo, Hiroshi Ito
  • Patent number: 4913116
    Abstract: There are provided a first ignition timing table for high-octane fuel and a second ignition timing table for low-octane fuel. When the second table is switched over to the first table, there is at first the difference in between basic ignition timings according to the first and second tables, and then the difference is reduced with time at a constant rate. An actual ignition timing during the switchover of an ignition timing table is determined by subtracting the reducing difference from the basic ignition timing according to the first table. The actual ignition timing when knocking is detected is compared with a predetermined threshold. If the former exceeds the latter, the second table is switched over to the first table, and otherwise the second table is maintained, whereby the actual ignition timing can be changed smoothly even during the switchover of an ignition timing table.
    Type: Grant
    Filed: March 7, 1989
    Date of Patent: April 3, 1990
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Kozo Katogi, Asahiko Otani
  • Patent number: 4911125
    Abstract: Disclosed is a method and apparatus for controlling a throttle valve driven by a D.C. motor in an internal combustion engine, in which the D.C. motor is driven until a valve position sensor detecting the angular position of the throttle valve generates an output signal which coincides with the output signal of an accelerator pedal sensor detecting the amount of depression of an accelerator pedal of a vehicle. The value of motor current required for causing very slight displacement of a return spring provided for returning the throttle valve toward a predetermined angular position is utilized for automatically compensating various factors of fluctuation attributable to friction, inertia, etc. of means driving the throttle valve. A small-capacity microprocessor is used to control the D.C. motor so that the throttle valve can operate with high accuracy and high-speed response capability without being adversely affected by changes in the operating condition as well as secular variations.
    Type: Grant
    Filed: March 31, 1989
    Date of Patent: March 27, 1990
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Hayato Sugawara, Shigeru Horikoshi, Kenji Ohta
  • Patent number: 4909079
    Abstract: A heat wire type airflow meter having a resistance element disposed within an airflow, the rate of which is measured, and a detection circuit for producing an airflow rate signal by detecting resistance change of the element depending on the airflow rate, in which the resistance element comprises a heat wire coil, lead wires attached to the heat wire coil at both ends thereof, a ceramic layer covering the heat wire coil and junctions of the heat wire coil and the lead wires to form a cylindrical member in such a manner that the heat wire coil is contained therein coaxially and along an inner surface thereof and a glass layer for coating an outer surface of the cylindrical member.
    Type: Grant
    Filed: June 23, 1989
    Date of Patent: March 20, 1990
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Yutaka Nishimura, Izumi Watanabe, Hiroshi Yoneda, Hiroatsu Tokuda
  • Patent number: 4909223
    Abstract: In an apparatus of the type in which the air-fuel ratio of an engine is detected by an air-fuel ratio sensor and the air-fuel ratio is feedback-controlled in accordance with the detection result to operate the engine at a desired air-fuel ratio, a change of the output characteristic of the air-fuel ratio sensor is always corrected for.
    Type: Grant
    Filed: September 6, 1988
    Date of Patent: March 20, 1990
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Takauki Ituzi, Sadayasu Ueno, Norio Ichikawa
  • Patent number: 4893502
    Abstract: Disclosed is a non-contact type throttle angle sensor sensing and converting angular rotation of a throttle valve of an internal combustion engine into an electrical signal. The sensor comprises a magnetic field generating element disposed on one end of a rotatable throttle shaft, a magneto-sensitive element disposed opposite to the field generating element at a position fixed relative to a throttle body and spaced apart from the field generating element, the magneto-sensitive element generating an output whose level changes with the rotation of the throttle valve shaft relative to the throttle body, a housing forming an integral part of the throttle body to accommodate the field generating element and the magneto-sensitive element, and an electrical circuit converting the output of the magneto-sensitive element into an electrical signal, the electrical circuit including a circuit adjusting the zero level and maximum level of the output of the magneto-sensitive element.
    Type: Grant
    Filed: August 3, 1988
    Date of Patent: January 16, 1990
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Masanori Kubota, Sadayasu Ueno, Kanemasa Sato, Kiyoshi Miura
  • Patent number: 4881407
    Abstract: The bobbin (21) of the heating resistor (1) is made by zirconia or glass fiber. On the surface of the bobbin, a platinum film (31) or a platinum wire (23) are formed. At both ends of the heating resistor, the heating resistor is supported by a pair of supporting conductors (25).
    Type: Grant
    Filed: October 8, 1987
    Date of Patent: November 21, 1989
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Minoru Tashahashi, Hiroastu Tokuda, Izumi Watanabe, Yutaka Nishimura
  • Patent number: 4879982
    Abstract: A method of and an apparatus for controlling the revolution speed of an engine, suitable for use in an automobile having an automatic transmission. Flow rate of auxiliary intake air by-passing a throttle valve is controlled by an auxiliary air control valve, the opening period of which is incremented in response to a signal which represents the state of the automatic transmission shifted from neutral range to a power range so as to avoid any reduction in the engine speed or the engine stall. The valve open time is controlled as a function of the engine cooling water temperature.
    Type: Grant
    Filed: August 22, 1988
    Date of Patent: November 14, 1989
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Tomiya Itakura, Hiroshi Kamifuji
  • Patent number: 4875539
    Abstract: An electric power steering control system includes an electric motor for producing an assisting torque for the vehicle steering system through a reduction gear, a steering torque sensor fitted on the steering shaft, a controller for controlling the input to the motor in accordance with the torque sensor output, a battery for supplying power to the controller, and a voltage step-up circuit connected to the battery for driving the motor at a voltage higher than the battery voltage. The controller drives the motor at a high voltage.
    Type: Grant
    Filed: March 31, 1988
    Date of Patent: October 24, 1989
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Toshimi Abukawa, Kazuo Tahara, Katsuji Murumoto, Toshiyuki Koterazawa, Mitsuyuki Hombu, Tadashi Takahashi, Shuichi Takamatsu, Hisatugu Ishikura, Hiroshisa Yamamura, Toru Tatsuzaki, Tsutomu Ohmae, Toshiaki Okuyama, Seizi Yamashita, Shigeki Saito, Masato Sakai
  • Patent number: 4854284
    Abstract: A rotation angle measuring apparatus comprises a throttle valve for controlling the amount of air flow of an internal combustion engine, a throttle sensor coupled to a rotation shaft of the throttle valve, and a logic circuit which includes absolute rotation angle detecting means for receiving an output signal of the throttle sensor to produce an absolute signal, forward/reverse rotation direction discriminating means for receiving an output signal of the throttle sensor to produce a direction signal, and an up/down counter for receiving the absolute signal, the direction signal and a count signal outputted from the forward/reverse rotation direction discriminating means to output a signal representative of a rotation position of the rotation shaft of the throttle valve.
    Type: Grant
    Filed: April 11, 1988
    Date of Patent: August 8, 1989
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Seiichiro Hara, Yoshikazu Hoshi
  • Patent number: 4831322
    Abstract: In a voltage regulator for charger/generator comprising a switching element, connected between a battery and a field winding of a generator adapted to charge the battery, for switching on and off an exciting current flowing through the field winding and a voltage detector responsive to voltage of the battery to control the operation of the switching element, there are provided an oscillator for generating an oscillation signal of a desired duty ratio, an initial excitation signal generator circuit having a plurality of stages of frequency dividers for dividing the frequency of the oscillation signal generated from the oscillator and combining together frequency division signals of the frequency dividers to produce a synthesized output signal of a desired duty ratio, a booster for boosting and rectifying an AC signal containing the oscillation signal of the oscillator and a signal which is opposite in phase to the oscillation signal to produce a boosted output signal, and excitation control means being operati
    Type: Grant
    Filed: May 2, 1988
    Date of Patent: May 16, 1989
    Assignees: Hitachi Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Keiichi Mashino, Shigekazu Takei
  • Patent number: 4799018
    Abstract: A detecting element (6) comprising a solid zirconia electrolyte (6a), a reference electrode (6d), a detecting electrode (6c) and a diffusion member (6a) is provided, and also a driving circuit (1b, 4) for impressing a voltage between the electrodes (6c, 6d) of said detecting element so as to detect the threshold current of an oxygen ion pumping current (I.sub.p) is provided. The output of this driving circuit is delivered as a continuous output (V.sub.o) of an air fuel ratio of fuel gas comprising al the regions of rich, stoichiometric and lean air fuel ratios. On the other hand, an I.sub.p detection resistor (Rs) for detecting the pumping current flowing between the input/output terminals of the driving circuit is provided. The opposite-end voltages (V.sub.a, V.sub.o) of this I.sub.p detection resistor are compared by a comparator (5), and a step signal corresponding to the stiochiometric air fuel ratio (.lambda.) is outputted from this comparator.
    Type: Grant
    Filed: August 11, 1987
    Date of Patent: January 17, 1989
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Norio Ichikawa, Takayuki Itsuji, Masayuki Miki
  • Patent number: 4756375
    Abstract: The present invention provides a controller for a power steering control system with a current limiter for limiting current to be fed to a power steering motor, in accordance with a power source voltage, whereby the power source is prevented from falling into an overdischarge state while a power steering function is performed. An additional feature of the present invention is an idle speed control device for increasing the engine idle speed when the current of the power steering motor reaches a predefined level.
    Type: Grant
    Filed: June 4, 1986
    Date of Patent: July 12, 1988
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Hisatugu Ishikura, Nobuyoshi Onuma, Shigeki Saito, Hiroyosi Sakurai
  • Patent number: 4715353
    Abstract: An ultrasonic wave type fuel atomizing apparatus for an internal combustion engine provided in an intake passage of the internal combustion engine and atomizing the fuel injected from a fuel injection pump by the ultrasonic wave vibration includes an ultrasonic wave vibrator, an oscillation circuit for generating ultrasonic waves for driving the ultrasonic wave vibrator, and a high voltage generating coil for boosting the output of the oscillation circuit and for applying the driving output to the ultrasonic wave vibrator, and furthermore, a feedback circuit is included to detect a current flowing through the high voltage generating coil and to control an oscillation frequency of the oscillation circuit thereby to make the driving frequency follow the resonance point of the ultrasonic wave vibrator.
    Type: Grant
    Filed: December 19, 1986
    Date of Patent: December 29, 1987
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Hiroshi Koike, Hiroshi Katada, Hiroshi Yoneda
  • Patent number: 4711620
    Abstract: A moving vane type compressor has a cylinder which is made of a sintered material having a density of 6.6 to 7.6 and a composition consisting essentially of 0.6 to 0.8% of carbon, 1 to 2% of copper and the balance substantially iron. The cylinder is encased by a hermetic casing therebetween a high pressure chamber into which a refrigerant compressed by the compressor is discharged. Lubricating oil separated from the discharged refrigerant within the high pressure chamber and the lubricating oil suspended in the form of a mist by the refrigerant attach to the outer peripheral surface of the wall of the cylinder made of the sintered material. The oil attaching to the outer peripheral surface of the cylinder is forced by the refrigerant pressure acting thereon into the pores of the sintered material such as to block these pores, thus preventing the compressed gas in the cylinder from leaking outside through the pores.
    Type: Grant
    Filed: May 28, 1985
    Date of Patent: December 8, 1987
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Yukio Takahashi, Isao Hayase, Keijirou Amano, Masao Mizukami, Masaaki Ishiguri
  • Patent number: 4697886
    Abstract: This invention discloses a color liquid crystal display device which can be applied to 7-segment numeric display, for example, A pair of transparent electrodes are disposed on the inner surfaces of a pair of transparent substrates facing each other. One of the transparent electrodes has a function as the display segments and is constituted by two comb tooth-like electrodes that are fixed in a predetermined direction. The direction of teeth of these two comb tooth-like electrodes is in agreement with each other. The other of the transparent electrodes has a flat sheet-like shape. Color filters of two colors are alternately disposed on the two comb tooth-like electrodes in such a manner as to face the other of the transparent electrodes. The direction of disposition of the color filters is in agreement with the direction of the teeth of the comb tooth-like electrodes. The color filters are disposed on the entire surface of the display range including the display segment.
    Type: Grant
    Filed: October 8, 1986
    Date of Patent: October 6, 1987
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Hiroshi Ito, Masaru Kugo, Sizuhisa Watanate
  • Patent number: 4676213
    Abstract: An air-fuel ratio control apparatus is disclosed in which an air-fuel ratio sensor disposed in the exhaust system of an internal combustion engine produces a voltage signal correlated with the excess air ratio of the ambient gas surrounding it and has such an output characteristic as to produce a maximum output only when the ambient gas is filled with air, the air-fuel ratio of the internal combustion engine being controlled to a proper value on the basis of the detection signal of the air-fuel ratio sensor. The air-fuel ratio control apparatus further comprises a sampling device for sampling the maximum output (V.sub.x) when it is decided that the output of the air-fuel ratio sensor is maintained for a predetermined length of time or longer at a predetermined value or higher, a memory for storing the sample value of the maximum output (V.sub.x) produced by the sampling device and updating the preceding sample value (V.sub.x-1) to the present sample value (V.sub.
    Type: Grant
    Filed: September 26, 1986
    Date of Patent: June 30, 1987
    Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.
    Inventors: Takayuki Itsuji, Sadayasu Ueno