Patents by Inventor Tokio Kohama

Tokio Kohama has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4517648
    Abstract: A torque variation in an internal combustion engine due to the combustion variations is detected at each predetermined period. An average torque variation to be compared with the detected torque variation is predetermined experimentally based on the engine speed and the intake manifold pressure and is stored in a memory. The number of the detected torque variations which exceed the average torque variation multiplied by a predetermined constant is counted, and if the ratio of the counted number to the total number of the detected torque variations is larger than a predetermined reference value, then the presence of a torque variation is determined.
    Type: Grant
    Filed: July 19, 1982
    Date of Patent: May 14, 1985
    Assignee: Nippon Soken, Inc.
    Inventors: Toshikazu Ina, Hisasi Kawai, Tokio Kohama, Hideki Obayashi, Daisaku Sawada, Takashi Shigematsu
  • Patent number: 4513721
    Abstract: In an air-fuel ratio control device, a torque detector for detecting torque variations which indicate combustion variations in an engine is mounted at the supporting portions of the internal combustion engine. A detecting signal from the torque detector is introduced into an electronic control unit which controls the amount of injecting fuel, namely the air-fuel ratio. The electronic control unit controls the air-fuel ratio toward the lean side by the signal from the torque detector so that the combustion variations (torque variations) in the engine does not become large.
    Type: Grant
    Filed: August 9, 1982
    Date of Patent: April 30, 1985
    Assignees: Nippon Soken, Inc., Toyota Jidosha Kabushiki Kaisha
    Inventors: Toshikazu Ina, Hideki Obayashi, Hisasi Kawai, Tokio Kohama, Daisaku Sawada, Takashi Shigematsu
  • Patent number: 4513626
    Abstract: A torque detector for detecting a torque applied to a load from a driving shaft is disclosed. The torque detector comprises an elastic member which is interposed between a first shaft connected to the driving shaft and a second shaft connected to the load so as to be connected thereto, an angular phase difference detecting means for detecting an angular phase difference occurring between the first shaft and the second shaft when the torque is transmitted from the first shaft to the second shaft through the elastic member, and a data processing means for calculating the torque from the detected angular phase difference.
    Type: Grant
    Filed: February 22, 1983
    Date of Patent: April 30, 1985
    Assignee: Nippon Soken, Inc.
    Inventors: Hideki Obayashi, Tokio Kohama, Kimitaka Saito, Hisasi Kawai, Toshikazu Ina
  • Patent number: 4513627
    Abstract: A torque detector, for detecting a torque applied to a torque transmission shaft which is connected to a load of an automobile, comprises an elastic member which is interposed between a driving shaft and the torque transmission shaft so as to be connected thereto, rotating members, each of which is integrally provided with the shafts, have a plurality of teeth or notches in the outer periphery thereof so as to be positioned in each combustion stroke of each piston of an engine of the automobile, electromagnetic pickups for detecting the passing of the teeth or notches and a data processing circuit for calculating torque at a predetermined rotating angle from the angular phase difference between the above two shafts, the torque occurring due to the deformation of the elastic member caused by the increase or decrease of applied torque. The processing means adds the calculated torque in each combustion stroke of each piston and averages the added torque.
    Type: Grant
    Filed: June 6, 1983
    Date of Patent: April 30, 1985
    Assignees: Nippon Soken, Inc., Nippondenso Co., Ltd.
    Inventors: Tokio Kohama, Hideki Obayashi, Kimitaka Saito, Toshikazu Ina, Seiichi Narita
  • Patent number: 4513628
    Abstract: A torque detector, for detecting a torque applied to a torque transmission shaft which is connected to a load such as a wheel of an automobile, comprises a first rotating member which is integrally connected to a driving shaft of an engine, a second rotating member which is integrally connected to a load so as to be opposed to the first rotating member, a plurality of elastic members for connecting the opposed surfaces of the first and second rotating members, an angular phase difference detecting circuit for detecting the angular phase difference between the first and second rotating members, a no load condition detecting circuit for detecting a no load condition of the engine, and a data processor for calculating torque from the angular phase difference between the first and second rotating members under the load condition and under the no load condition. An accurate value of applied torque is detected by subtracting the angular phase difference under the no load condition from the load condition.
    Type: Grant
    Filed: June 6, 1983
    Date of Patent: April 30, 1985
    Assignees: Nippon Soken, Inc., Nippondenso Co., Inc.
    Inventors: Tokio Kohama, Hideki Obayashi, Toshikazu Ina, Seiichi Narita
  • Patent number: 4503713
    Abstract: A torque detector, particularly a torque detector for detecting a torque applied to a torque transmission shaft which is connected to a load such as a wheel of an automobile, comprises a first shaft connected to a driving shaft, a second shaft connected to a torque transmission shaft, and a plurality of elastic members, each of which is interposed between the first shaft and the second shaft for transmitting the torque of the first shaft to the second shaft while receiving the compression force between the first shaft and the second shaft when the driving shaft is driven. The first shaft comprises a flange portion wherein a plurality of long grooves are formed so as to extend in the rotating direction thereof. The second shaft comprises a flange portion wherein a plurality of long holes are formed so as to extend in the rotating direction thereof and penetrate therethrough at such positions as to be substantially opposed to said long grooves.
    Type: Grant
    Filed: April 20, 1983
    Date of Patent: March 12, 1985
    Assignee: Nippon Soken, Inc.
    Inventors: Hideki Obayashi, Tokio Kohama, Kimitaka Saito, Hisasi Kawai, Toshikazu Ina
  • Patent number: 4499882
    Abstract: A system for controlling the air-fuel ratio of an internal combustion engine includes a transient fuel amount increasing device for regulating the supply fuel amount in the transient state of the engine on the basis of the detection of the transient state of the engine, an air-fuel ratio deviation detecting device for detecting the air-fuel ratio deviation from the optimum air-fuel ratio, and a transient fuel increase amount correcting device for correcting the fuel increase amount in the transient state of the engine in accordance with the air-fuel ratio deviation detected by the air-fuel ratio deviation detecting device. The air-fuel deviation from the optimum air-fuel ratio of the air-fuel mixture upon deposition of a deposit on the back surface of the intake valve is prevented, and the drivability of an automobile is improved.
    Type: Grant
    Filed: December 29, 1983
    Date of Patent: February 19, 1985
    Assignees: Nippon Soken, Inc., Toyota Jidosha Kabushiki Kaisha
    Inventors: Kimitaka Saito, Tokio Kohama, Tsuneyuki Egami, Tsutomu Saito, Susumu Nogami, Yukio Suzuki
  • Patent number: 4489695
    Abstract: The number of working cylinders of the internal combustion engine is controlled so that the load of the internal combustion engine is relatively increased thereby to keep the combustion effect within an expected range. By controlling the number of working cylinders of the internal combustion engine also to other than integral numbers, the torque control of large freedom is continuously effected. Thus the torque characteristic is smoothed, thus improving the fuel efficiency and driveability at the same time.
    Type: Grant
    Filed: January 27, 1982
    Date of Patent: December 25, 1984
    Assignee: Nippon Soken, Inc.
    Inventors: Tokio Kohama, Seizi Huzino, Hideki Obayashi, Hisasi Kawai, Tsuneyuki Egami
  • Patent number: 4478185
    Abstract: A method for regulating the air-fuel ratio and an ignition fiming in an internal combustion engine, using a device for sensing the engine running state, a device for detecting the variation in engine combustion, a device for correcting the air-fuel ratio supplied in the engine according to the detected combustion variation, and an device for controlling the ignition timing. The ignition timing control device calculates the interpolated basic advance angle value .theta..sub.b, the corrected advance angle value .DELTA..theta., and, hence, the resultant advance angle value .theta. for use in the ignition timing control, so as to attain the air-fuel ratio giving the best rate of fuel consumption.
    Type: Grant
    Filed: April 11, 1983
    Date of Patent: October 23, 1984
    Assignees: Nippon Soken, Inc., Toyota Jidosha Kabushiki Kaisha
    Inventors: Hideki Obayashi, Tokio Kohama, Hisasi Kawai, Toshikazu Ina, Daisaku Sawada, Takashi Shigematsu
  • Patent number: 4475388
    Abstract: A method for measuring the flow rate of fluid such as liquified petroleum gas fuel for an automobile fuel. A signal of the fluid flow rate and a signal of the fluid temperature are produced by using the signals from an electric heater and a first, second, and third temperature-dependent resistors in a signal processing circuit. The produced signals are supplied to a computer circuit to carry out modification, linearization, and multiplication by a conversion constant for linearization which is corrected regarding temperature characteristic. The result of calculation in the computer circuit is displayed on a display device.
    Type: Grant
    Filed: October 7, 1982
    Date of Patent: October 9, 1984
    Assignees: Nippon Soken, Inc., Toyota Jidosha Kabushiki Kaisha
    Inventors: Hisasi Kawai, Norihito Tokura, Tokio Kohama, Kenji Kanehara, Takayoshi Ito, Kazutaka Hasegawa
  • Patent number: 4471655
    Abstract: An apparatus for measuring the flow rate of a gas wherein resistance wires whose resistance value changes in accordance with temperature are arranged in a flow rate measuring tube providing a path of a gas to be measured, a voltage is applied to the resistance wires to detect the change in resistance value of the resistance wires due to the change in temperature thereof in accordance with the gas flow rate, and the flow rate of the gas is measured. In order to support the resistance wires in the flow rate measuring tube, the support members for supporting the resistance wires have respectively two support rods provided with grooves at positions corresponding to the turning points of the resistance wires wound thereon so that the resistance wires are supported stably lying in the grooves.
    Type: Grant
    Filed: October 20, 1981
    Date of Patent: September 18, 1984
    Assignee: Nippon Soken, Inc.
    Inventors: Hideki Obayashi, Tokio Kohama, Hisasi Kawai, Tsuneyuki Egami
  • Patent number: 4442820
    Abstract: In an exhaust gas recirculation system including a recirculation passage to provide a communication between an intake pipe and an exhaust pipe of an internal combustion engine, a flow control valve associated with a pneumatic servomotor to control the quantity of exhaust gas flowing through the recirculation passage in accordance with the pneumatic pressure applied to the servomotor, and first and second electrically operated valves to selectively apply negative pressure and the atmospheric pressure to the servomotor, a digital computer is adapted to calculate a desired opening degree of the flow control valve in response to an electric signal indicative of operating conditions of the engine, to calculate each energization time of the valves defined by a difference between the actual opening degree of the flow control valve and the calculated value in response to an electric signal indicative of the actual opening degree of the flow control valve, and to generate an output signal indicative of the calculated
    Type: Grant
    Filed: September 10, 1982
    Date of Patent: April 17, 1984
    Assignees: Nippon Soken, Inc., Toyota Jidosha Kabushiki Kaisha
    Inventors: Toshikazu Ina, Hisasi Kawai, Tokio Kohama, Akira Nishimatsu, Yasuhiko Ishida, Souichi Matsusita
  • Patent number: 4437345
    Abstract: A gas flow measuring device has a measuring circuit for measuring the flow of gas based on the output signals of an electric heater and a first and a second temperature dependent resistor. In the measuring circuit, the first and the second temperature dependent resistors, together with first and second reference resistors, form a bridge and a constant voltage is applied to a voltage at one diametrical point of the bridge. The difference between the other voltage of the diametrical point of the bridge and the output of the constant voltage adding circuit is amplified, and the output voltage of the amplifier circuit is further amplified so that the voltage applied to the electric heater and the bridge is feed-back controlled.
    Type: Grant
    Filed: March 30, 1982
    Date of Patent: March 20, 1984
    Assignee: Nippon Soken, Inc.
    Inventors: Tsuneyuki Egami, Hisasi Kawai, Tokio Kohama, Hideki Obayashi
  • Patent number: 4434767
    Abstract: In the range where the fuel efficiency may be improved by relatively increasing the load of working cylinders at the time of partial loading of a multicylinder internal combustion engine, the intake pressure of the engine is maintained at a fixed optimum value. Also, the number of working cylinders is controlled, so that a torque actually required by the driver is obtained, and under any load, the maximum improvement of fuel efficiency may be attained at a saving of fuel consumption.
    Type: Grant
    Filed: December 23, 1981
    Date of Patent: March 6, 1984
    Assignee: Nippon Soken, Inc.
    Inventors: Tokio Kohama, Seizi Huzino, Hideki Obayashi, Hisasi Kawai, Tsuneyuki Egami
  • Patent number: 4425792
    Abstract: In a fluid flow rate measuring apparatus having a sensor including an electric heater resistance wire and first and second temperature dependent resistance wires and a measuring circuit, each of the resistance wires is wound to be held firmly in place on a supporting member made of an electrical insulating material, and the electric heater resistance wire and the first temperature dependent resistance wire, which is responsive to the temperature of the fluid under measurement heated by the electric heater resistance wire, are wound on the same supporting member alternately and close to each other so that the winding direction thereof makes an angle from 60.degree. to 120.degree. to the direction of the flow of the fluid under measurement. Further, each of the supporting members is constructed and arranged so as to minimize the influence of the heat capacity thereof and also to avoid the occurrence of turbulence in the flow of the fluid which is detrimental to the flow rate measurement.
    Type: Grant
    Filed: May 7, 1982
    Date of Patent: January 17, 1984
    Assignee: Nippon Soken, Inc.
    Inventors: Tokio Kohama, Hideki Obayashi, Hisasi Kawai, Tsuneyuki Egami
  • Patent number: 4417471
    Abstract: A first temperature dependent resistor and a second temperature dependent resistor are disposed within a single gas passage defined by a branch pipe extending into a conduit for a gas whose flow rate is to be measured. An electric heater is located between these temperature dependent resistors and is heated for the purpose of measurement of the flow rate of the gas. A first reference resistor and a second reference resistor constitute a bridge circuit together with the first and second temperature dependent resistors, and the difference between the potentials at the terminals of the bridge circuit is amplified by a first differential amplifier circuit. The difference between the output voltage of the first differential amplifier circuit and a predetermined reference voltage is then amplified by a second differential amplifier circuit.
    Type: Grant
    Filed: November 23, 1981
    Date of Patent: November 29, 1983
    Assignee: Nippon Soken, Inc.
    Inventors: Hisasi Kawai, Tsuneyuki Egami, Tokio Kohama, Hideki Obayashi
  • Patent number: 4414847
    Abstract: A gas flow rate measuring apparatus for measuring the intake air flow rate of an automobile engine or the like is disclosed, which comprises a flow rate measuring tube containing an electric heater resistance wire and two temperature-dependent resistance wires, one subject to the effect of heat of the electric heater and the other free from the effect. An output signal of a voltage divider circuit including the series-connected temperature-dependent resistance wires is used to measure the gas flow rate. The electric heater resistance wire and the temperature-dependent resistance wire thermally affected thereby are wound side by side but avoiding occurrence of any short-circuit therebetween on a single support member of an electrically insulating material.
    Type: Grant
    Filed: July 23, 1981
    Date of Patent: November 15, 1983
    Assignee: Nippon Soken, Inc.
    Inventors: Tokio Kohama, Hisasi Kawai, Hideki Obayashi, Tsuneyuki Egami
  • Patent number: 4409828
    Abstract: An electric heater connected between first and second temperature dependent resistors provided inside a pipe through which the gas the flow of which is to be measured is heated for the measurement of the gas flow. A voltage control circuit controls the voltage applied to or current through the electric heater such as to maintain a constant potential difference between diagonal points of a bridge circuit which is formed by the first and second temperature dependent resistors and first and second reference resistors. An output computing circuit which receives a signal proportional to the voltage across the electric heater and also to the current therethrough produces an output signal representing the rate of flow of gas being measured.
    Type: Grant
    Filed: April 7, 1981
    Date of Patent: October 18, 1983
    Assignee: Nippon Soken, Inc.
    Inventors: Tokio Kohama, Hideki Obayashi, Hisasi Kawai, Tsuneyuki Egami
  • Patent number: 4399697
    Abstract: A gas flow measuring apparatus for measuring intake air flow for an automobile engine having an electrical heater resistive member, and first and second temperature dependent resistive members. The first resistive member is located so as to be well influenced by heat from the heater resistive member, while the second resistive member is located so as to be little influenced by the same. The measuring apparatus measures a gas flow rate by using an output signal from a voltage dividing circuit as a series circuit of the first and second resistive members. In the gas flow measuring apparatus, a heater film resistive member is deposited on a first support member by an evaporation depositing or printing process, and is further covered with electric insulating material such as glass.
    Type: Grant
    Filed: March 24, 1981
    Date of Patent: August 23, 1983
    Assignee: Nippon Soken, Inc.
    Inventors: Tokio Kohama, Hideki Obayashi, Hisasi Kawai, Tsuneyuki Egami
  • Patent number: 4393702
    Abstract: A first temperature dependent resistor, an electric heater and a second temperature dependent resistor are arranged in this order within and from the downstream to the upstream of a pipe in which flows a gas whose flow rate is to be measured. A bridge circuit is formed by the first and second temperature dependent resistors along with first and second reference resistors. In response to the output of the bridge circuit, a measuring circuit regulates the supply of power to the electric heater and generates a signal indicative of the flow rate of the gas. Each of the first and second reference resistors is in the form of a film resistor formed on an insulating base. The insulating base having the film resistors formed thereon is placed for example in the flow of the gas to be measured.
    Type: Grant
    Filed: March 11, 1981
    Date of Patent: July 19, 1983
    Assignee: Nippon Soken, Inc.
    Inventors: Tokio Kohama, Hideki Obayashi, Hisasi Kawai, Tsuneyuki Egami