Patents by Inventor Osamu Kawatoko

Osamu Kawatoko 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: 11422009
    Abstract: A rotary encoder that is capable of securing a sufficient synthesis tolerance while achieving miniaturization is provided. The rotary encoder 1 includes a rotor 3, a stator 4, and a calculating unit 5 for calculating the rotation angle. The rotor 3 has a first rotor pattern 31 with a plurality of unit patterns 310 arranged along the measurement direction around the rotating shaft 2, and a second rotor pattern 32 with fewer unit patterns 320 than the plurality of unit patterns 310 in the first rotor pattern 310 arranged along the measurement direction. The number of the plurality of unit patterns 310 of the first rotor pattern 31 and the number of the plurality of unit patterns 320 of the second rotor pattern 32 are provided such that the maximum common divisor therebetween is two or more. The calculating unit calculates the rotation angle of the rotor 3 based on the detection signals from the first rotor pattern 31 and the second rotor pattern 32.
    Type: Grant
    Filed: January 8, 2021
    Date of Patent: August 23, 2022
    Assignee: MITUTOYO CORPORATION
    Inventors: Osamu Kawatoko, Hirokazu Kobayashi
  • Patent number: 11340095
    Abstract: An object is to respectively excite transmission coils with different voltages using a single power supply with low power consumption in an electromagnetic induction type encoder. A detection head of an encoder includes a voltage adjustment circuit and a plurality of excitation circuits. The excitation circuit includes a resonant circuit that includes a driving capacitor and a transmission coil connected in series and generates an alternate-current magnetic field inducing currents in scale coils disposed in a plurality of scale tracks on a scale by connecting both ends of the resonant circuit in a state in which the driving capacitor is charged. The voltage adjustment circuit includes a first transformer capacitor and controls a charging voltage of the driving capacitor in a single excitation circuit using the charged first transformer capacitor.
    Type: Grant
    Filed: October 22, 2020
    Date of Patent: May 24, 2022
    Assignee: MITUTOYO CORPORATION
    Inventors: Osamu Kawatoko, Toshihiro Hasegawa, Tomohiro Tahara, Akio Kawai
  • Patent number: 11137269
    Abstract: A reference voltage generator circuit generates a reference voltage corresponding to a power supply voltage. A current/voltage converter circuit converts a photocurrent output by a photoreceiver into voltage, and outputs a voltage obtained by adding the converted voltage and the reference voltage. A sample and hold circuit holds a voltage of a capacitor in response to a sample and hold signal, the capacitor having the voltage input at one end and the reference voltage input at another end. An amplifier circuit outputs an output signal where a voltage held by the sample and hold circuit is amplified with the reference voltage as a reference.
    Type: Grant
    Filed: November 6, 2017
    Date of Patent: October 5, 2021
    Assignee: MITUTOYO CORPORATION
    Inventors: Osamu Kawatoko, Tomohiro Tahara, Hirokazu Kobayashi
  • Publication number: 20210215511
    Abstract: A rotary encoder that is capable of securing a sufficient synthesis tolerance while achieving miniaturization is provided. The rotary encoder 1 includes a rotor 3, a stator 4, and a calculating unit 5 for calculating the rotation angle. The rotor 3 has a first rotor pattern 31 with a plurality of unit patterns 310 arranged along the measurement direction around the rotating shaft 2, and a second rotor pattern 32 with fewer unit patterns 320 than the plurality of unit patterns 310 in the first rotor pattern 310 arranged along the measurement direction. The number of the plurality of unit patterns 310 of the first rotor pattern 31 and the number of the plurality of unit patterns 320 of the second rotor pattern 32 are provided such that the maximum common divisor therebetween is two or more. The calculating unit calculates the rotation angle of the rotor 3 based on the detection signals from the first rotor pattern 31 and the second rotor pattern 32.
    Type: Application
    Filed: January 8, 2021
    Publication date: July 15, 2021
    Inventors: Osamu Kawatoko, Hirokazu Kobayashi
  • Publication number: 20210131831
    Abstract: An object is to respectively excite transmission coils with different voltages using a single power supply with low power consumption in an electromagnetic induction type encoder. A detection head of an encoder includes a voltage adjustment circuit and a plurality of excitation circuits. The excitation circuit includes a resonant circuit that includes a driving capacitor and a transmission coil connected in series and generates an alternate-current magnetic field inducing currents in scale coils disposed in a plurality of scale tracks on a scale by connecting both ends of the resonant circuit in a state in which the driving capacitor is charged. The voltage adjustment circuit includes a first transformer capacitor and controls a charging voltage of the driving capacitor in a single excitation circuit using the charged first transformer capacitor.
    Type: Application
    Filed: October 22, 2020
    Publication date: May 6, 2021
    Inventors: Osamu Kawatoko, Toshihiro Hasegawa, Tomohiro Tahara, Akio Kawai
  • Patent number: 10551224
    Abstract: An encoder includes a light source. A booster circuit boosts a power supply voltage output by a battery, and outputs the boosted voltage. The voltage is applied to one end of a light-emitting diode. A driver circuit is inserted between another end of the light-emitting diode and a ground, the driver circuit controlling current flowing through the light-emitting diode. A voltage detector circuit detects a voltage between the light-emitting diode and the driver circuit. A control circuit causes the booster circuit to boost the power supply voltage when the voltage is lower than the power supply voltage; stops the boosting performed by the booster circuit when the voltage is equal to the power supply voltage; and controls the driver circuit such that, after the voltage reaches a predetermined value, current flows to the light-emitting diode.
    Type: Grant
    Filed: November 22, 2017
    Date of Patent: February 4, 2020
    Assignee: MITUTOYO CORPORATION
    Inventors: Hirokazu Kobayashi, Osamu Kawatoko
  • Patent number: 10520336
    Abstract: The displacement detector is configured to receive a transmission signal output from a transmission signal output unit by a reception electrode disposed in a detection head to detect a displacement between the detection head and a scale based on the received signal. The transmission signal is transmitted from a transmission electrode disposed in the detection head to the reception electrode through a coupling electrode disposed in the scale. Phase adjustment units generates a signal whose phase is adjusted from the transmission signal output from the transmission signal output unit. An amplitude adjustment unit adjusts an amplitude of the signal whose phase is adjusted by the phase adjustment unit to generate a crosstalk correction signal. A demodulation unit samples a signal generated by synthesizing the crosstalk correction signal and the received signal and to demodulate the sampled signal.
    Type: Grant
    Filed: January 12, 2018
    Date of Patent: December 31, 2019
    Assignee: MITUTOYO CORPORATION
    Inventors: Osamu Kawatoko, Masaki Matsushita
  • Publication number: 20180216971
    Abstract: The displacement detector is configured to receive a transmission signal output from a transmission signal output unit by a reception electrode disposed in a detection head to detect a displacement between the detection head and a scale based on the received signal. The transmission signal is transmitted from a transmission electrode disposed in the detection head to the reception electrode through a coupling electrode disposed in the scale. Phase adjustment units generates a signal whose phase is adjusted from the transmission signal output from the transmission signal output unit. An amplitude adjustment unit adjusts an amplitude of the signal whose phase is adjusted by the phase adjustment unit to generate a crosstalk correction signal. A demodulation unit samples a signal generated by synthesizing the crosstalk correction signal and the received signal and to demodulate the sampled signal.
    Type: Application
    Filed: January 12, 2018
    Publication date: August 2, 2018
    Inventors: Osamu Kawatoko, Masaki Matsushita
  • Publication number: 20180156640
    Abstract: An encoder includes a light source. A booster circuit boosts a power supply voltage output by a battery, and outputs the boosted voltage. The voltage is applied to one end of a light-emitting diode. A driver circuit is inserted between another end of the light-emitting diode and a ground, the driver circuit controlling current flowing through the light-emitting diode. A voltage detector circuit detects a voltage between the light-emitting diode and the driver circuit. A control circuit causes the booster circuit to boost the power supply voltage when the voltage is lower than the power supply voltage; stops the boosting performed by the booster circuit when the voltage is equal to the power supply voltage; and controls the driver circuit such that, after the voltage reaches a predetermined value, current flows to the light-emitting diode.
    Type: Application
    Filed: November 22, 2017
    Publication date: June 7, 2018
    Applicant: MITUTOYO CORPORATION
    Inventors: Hirokazu KOBAYASHI, Osamu KAWATOKO
  • Publication number: 20180143040
    Abstract: A reference voltage generator circuit generates a reference voltage corresponding to a power supply voltage. A current/voltage converter circuit converts a photocurrent output by a photoreceiver into voltage, and outputs a voltage obtained by adding the converted voltage and the reference voltage. A sample and hold circuit holds a voltage of a capacitor in response to a sample and hold signal, the capacitor having the voltage input at one end and the reference voltage input at another end. An amplifier circuit outputs an output signal where a voltage held by the sample and hold circuit is amplified with the reference voltage as a reference.
    Type: Application
    Filed: November 6, 2017
    Publication date: May 24, 2018
    Applicant: MITUTOYO CORPORATION
    Inventors: Osamu KAWATOKO, Tomohiro TAHARA, Hirokazu KOBAYASHI
  • Patent number: 9739587
    Abstract: A semiconductor integrated circuit includes a regulator configured to stabilize a power supply voltage from a solar cell and to output the same, a voltage detection circuit configured to detect the power supply voltage from the solar cell or an output voltage from the regulator, a power-on-reset circuit configured to output a reset signal to an external digital circuit by a voltage detection signal output from the voltage detection circuit, a memory main body configured to write and read data by the power supply voltage from the solar cell or the output voltage from the regulator.
    Type: Grant
    Filed: June 18, 2015
    Date of Patent: August 22, 2017
    Assignee: MITUTOYO CORPORATION
    Inventors: Osamu Kawatoko, Akio Kawai
  • Publication number: 20150369580
    Abstract: A semiconductor integrated circuit includes a regulator configured to stabilize a power supply voltage from a solar cell and to output the same, a voltage detection circuit configured to detect the power supply voltage from the solar cell or an output voltage from the regulator, a power-on-reset circuit configured to output a reset signal to an external digital circuit by a voltage detection signal output from the voltage detection circuit, a memory main body configured to write and read data by the power supply voltage from the solar cell or the output voltage from the regulator.
    Type: Application
    Filed: June 18, 2015
    Publication date: December 24, 2015
    Inventors: Osamu Kawatoko, Akio Kawai
  • Patent number: 9121734
    Abstract: In a photoelectric absolute encoder including a scale having a plurality of tracks with different pitch patterns, and a detector having a light source and light receiving elements including a plurality of light receiving element arrays corresponding to the plurality of tracks, a light receiving element array is additionally arranged at a position in the detector corresponding to a boundary between the track having a pattern with a wide pitch and the track having a pattern with a narrow pitch adjacent to each other in the scale, and displacement of the detector relative to the scale in a lateral direction is detected from a signal amplitude of the added light receiving element array. In this manner, displacement of the detector relative to the scale in the lateral direction can be detected.
    Type: Grant
    Filed: December 2, 2013
    Date of Patent: September 1, 2015
    Assignee: MITUTOYO CORPORATION
    Inventors: Osamu Kawatoko, Hirokazu Kobayashi
  • Patent number: 8878523
    Abstract: An inductive detection encoder according to the present invention includes: first and second members which are oppositely disposed so as to relatively move in a measurement direction; a transmitting coil formed in the first member; a magnetic flux coupled body which is formed in the second member and coupled with a magnetic field generated by the transmitting coil; and a receiving coil formed in the first member and having receiving loops. At least one of the transmitting coil and the receiving coil has a specific pattern that impairs the uniformity and periodicity of a pattern; and a dummy pattern formed in a position corresponding to a specific phase relationship of a cycle generated by the track with respect to the specific pattern.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: November 4, 2014
    Assignee: Mitutoyo Corporation
    Inventors: Hirokazu Kobayashi, Osamu Kawatoko, Shozaburo Tsuji, Kenichi Nakayama
  • Patent number: 8847583
    Abstract: An electromagnetic induction type absolute position measuring encoder having two or more rows of scale coils, each of the rows having a scale pitch different from that of another row; a transmitter coil and a receiver coil arranged on a grid that is movable relative to the scale in the measuring direction so as to face the scale coils; and the track is constituted by the scale coils, the transmitter coil and the receiver coil. The encoder is capable of measuring an absolute position of the grid with respect to the scale from a flux change detected at the receiver coil via the scale coils when the transmitter coil is excited, in which at least one loop-shaped additional scale coil is added between the scale coils in at least one of the tracks.
    Type: Grant
    Filed: August 1, 2012
    Date of Patent: September 30, 2014
    Assignee: Mitutoyo Corporation
    Inventors: Kouji Sasaki, Osamu Kawatoko
  • Publication number: 20140151539
    Abstract: In a photoelectric absolute encoder including a scale having a plurality of tracks with different pitch patterns, and a detector having a light source and light receiving elements including a plurality of light receiving element arrays corresponding to the plurality of tracks, a light receiving element array is additionally arranged at a position in the detector corresponding to a boundary between the track having a pattern with a wide pitch and the track having a pattern with a narrow pitch adjacent to each other in the scale, and displacement of the detector relative to the scale in a lateral direction is detected from a signal amplitude of the added light receiving element array. In this manner, displacement of the detector relative to the scale in the lateral direction can be detected.
    Type: Application
    Filed: December 2, 2013
    Publication date: June 5, 2014
    Applicant: MITUTOYO CORPORATION
    Inventors: Osamu Kawatoko, Hirokazu Kobayashi
  • Patent number: 8441253
    Abstract: A measuring apparatus includes: a measuring circuit configured to carry out predetermined processing for the measurement result of an object to be measured; a communication control circuit configured to generate output data to be output externally depending on the processing result of the measuring circuit; a power source circuit having a charging element configured to supply power to the measuring circuit and the communication control circuit; an output circuit having open-drain output terminals configured to externally output the output data generated in the communication control circuit; and a charge control circuit configured to charge the charging element at the timing when the output data is not output externally, the open-drain output terminals of the output circuit being used as the input terminals thereof.
    Type: Grant
    Filed: August 24, 2011
    Date of Patent: May 14, 2013
    Assignee: Mitutoyo Corporation
    Inventors: Osamu Kawatoko, Toshihiro Hasegawa
  • Publication number: 20130069637
    Abstract: An inductive detection encoder according to the present invention includes: first and second members which are oppositely disposed so as to relatively move in a measurement direction; a transmitting coil formed in the first member; a magnetic flux coupled body which is formed in the second member and coupled with a magnetic field generated by the transmitting coil; and a receiving coil formed in the first member and having receiving loops. At least one of the transmitting coil and the receiving coil has a specific pattern that impairs the uniformity and periodicity of a pattern; and a dummy pattern formed in a position corresponding to a specific phase relationship of a cycle generated by the track with respect to the specific pattern.
    Type: Application
    Filed: September 14, 2012
    Publication date: March 21, 2013
    Applicant: MITUTOYO CORPORATION
    Inventors: Hirokazu Kobayashi, Osamu Kawatoko, Shozaburo Tsuji, Kenichi Nakayama
  • Publication number: 20130033257
    Abstract: An electromagnetic induction type absolute position measuring encoder having two or more rows of scale coils, each of the rows having a scale pitch different from that of another row; a transmitter coil and a receiver coil arranged on a grid that is movable relative to the scale in the measuring direction so as to face the scale coils; and the track is constituted by the scale coils, the transmitter coil and the receiver coil. The encoder is capable of measuring an absolute position of the grid with respect to the scale from a flux change detected at the receiver coil via the scale coils when the transmitter coil is excited, in which at least one loop-shaped additional scale coil is added between the scale coils in at least one of the tracks.
    Type: Application
    Filed: August 1, 2012
    Publication date: February 7, 2013
    Applicant: MITUTOYO CORPORATION
    Inventors: Kouji Sasaki, Osamu Kawatoko
  • Publication number: 20120049840
    Abstract: A measuring apparatus includes: a measuring circuit configured to carry out predetermined processing for the measurement result of an object to be measured; a communication control circuit configured to generate output data to be output externally depending on the processing result of the measuring circuit; a power source circuit having a charging element configured to supply power to the measuring circuit and the communication control circuit; an output circuit having open-drain output terminals configured to externally output the output data generated in the communication control circuit; and a charge control circuit configured to charge the charging element at the timing when the output data is not output externally, the open-drain output terminals of the output circuit being used as the input terminals thereof.
    Type: Application
    Filed: August 24, 2011
    Publication date: March 1, 2012
    Applicant: MITUTOYO CORPORATION
    Inventors: Osamu KAWATOKO, Toshihiro HASEGAWA