Patents by Inventor Akio Atsuta

Akio Atsuta 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: 9000691
    Abstract: Provided is a method of controlling a vibration motor, in which there are provided: a unit that generates a drive signal for generating elliptic motion; a unit that switches the drive signal with a voltage from a power supply, and changes a pulse width of the drive signal; a unit that detects a current flowing in an electromechanical energy conversion element through the switching unit; a unit that detects a position and a velocity of an object to be driven; and a control unit that controls the respective units, and sets the velocity of the object to be driven. The control unit controls a frequency and the pulse width of the drive signal so as to exercise a maximum output characteristic with respect to a target velocity within a range in which the current detected by the current detection unit does not exceed a given limit value.
    Type: Grant
    Filed: May 13, 2011
    Date of Patent: April 7, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventor: Akio Atsuta
  • Patent number: 8957609
    Abstract: Provided is a method of controlling a vibration motor, in which there are provided: a unit that generates a drive signal for generating elliptic motion; a unit that switches the drive signal with a voltage from a power supply, and changes a pulse width of the drive signal; a unit that detects a current flowing in an electromechanical energy conversion element through the switching unit; a unit that detects a position and a velocity of an object to be driven; and a control unit that controls the respective units, and sets the velocity of the object to be driven. The control unit controls a frequency and the pulse width of the drive signal so as to exercise a maximum output characteristic with respect to a target velocity within a range in which the current detected by the current detection unit does not exceed a given limit value.
    Type: Grant
    Filed: May 13, 2011
    Date of Patent: February 17, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventor: Akio Atsuta
  • Publication number: 20140145649
    Abstract: A driving apparatus of a vibration-type actuator includes a driving circuit configured to drive a vibration unit including a plurality of vibrators, a detection unit configured to detect a sum of power consumption consumed by the plurality of vibrators, and a driving frequency setting unit configured to set a driving frequency within a frequency range depending on the sum of power consumption detected by the detection unit.
    Type: Application
    Filed: November 21, 2013
    Publication date: May 29, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Akio Atsuta
  • Publication number: 20140101905
    Abstract: A vibration actuator includes an elastic body on which at least one projection is formed and a vibrating body including an electromechanical conversion device, and drives a driven member that is in contact with a contact portion of the projection by causing an end portion of the projection to perform an ellipsoidal movement in response to a combination of two vibration modes generated in the vibrating body when an alternating driving voltage is applied. The elastic body is formed integrally with the projection and a bonding portion between the projection and the electromechanical conversion device. A space is provided between the contact portion and the electromechanical conversion device to which the projection is bonded. The spring portion is provided between the bonding portion and the contact portion and causes the projection to exhibit a spring characteristic when the contact portion is pressed by the driven member.
    Type: Application
    Filed: December 18, 2013
    Publication date: April 17, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yuki Oda, Shinji Yamamoto, Akio Atsuta
  • Patent number: 8633632
    Abstract: A vibration actuator includes an elastic body on which at least one projection is formed and a vibrating body including an electromechanical conversion device, and drives a driven member that is in contact with a contact portion of the projection by causing an end portion of the projection to perform an ellipsoidal movement in response to a combination of two vibration modes generated in the vibrating body when an alternating driving voltage is applied. The elastic body is formed integrally with the projection and a bonding portion between the projection and the electromechanical conversion device. A space is provided between the contact portion and the electromechanical conversion device to which the projection is bonded. The spring portion is provided between the bonding portion and the contact portion and causes the projection to exhibit a spring characteristic when the contact portion is pressed by the driven member.
    Type: Grant
    Filed: March 21, 2011
    Date of Patent: January 21, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yuki Oda, Shinji Yamamoto, Akio Atsuta
  • Publication number: 20130076922
    Abstract: A correcting optical device according to an aspect of the present invention in which, when image shake is not corrected, a restricting member is caused to engage an engaging portion, to restrict translational movement of a movable member, and in which, when the image shake is corrected, the restricting member is caused to disengage the engaging portion, to cause the movable member to be in a state capable of the translational movement, the restricting member being provided at the rotary member, the engaging portion being provided at the movable member. A driving unit drives the movable member in a direction in which the movable member moves translationally with respect to a fixed member in a plane perpendicular to an optical axis of a correcting lens, so that the correcting lens corrects the image shake, and drives the rotary member in a direction in which the rotary member rotates around the optical axis.
    Type: Application
    Filed: July 24, 2012
    Publication date: March 28, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Makoto Shihoh, Akio Atsuta, Shinya Kudo
  • Publication number: 20110291595
    Abstract: Provided is a method of controlling a vibration motor, in which there are provided: a unit that generates a drive signal for generating elliptic motion; a unit that switches the drive signal with a voltage from a power supply, and changes a pulse width of the drive signal; a unit that detects a current flowing in an electromechanical energy conversion element through the switching unit; a unit that detects a position and a velocity of an object to be driven; and a control unit that controls the respective units, and sets the velocity of the object to be driven. The control unit controls a frequency and the pulse width of the drive signal so as to exercise a maximum output characteristic with respect to a target velocity within a range in which the current detected by the current detection unit does not exceed a given limit value.
    Type: Application
    Filed: May 13, 2011
    Publication date: December 1, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Akio Atsuta
  • Publication number: 20110234042
    Abstract: A vibration actuator includes an elastic body on which at least one projection is formed and a vibrating body including an electromechanical conversion device, and drives a driven member that is in contact with a contact portion of the projection by causing an end portion of the projection to perform an ellipsoidal movement in response to a combination of two vibration modes generated in the vibrating body when an alternating driving voltage is applied. The elastic body is formed integrally with the projection and a bonding portion between the projection and the electromechanical conversion device. A space is provided between the contact portion and the electromechanical conversion device to which the projection is bonded. The spring portion is provided between the bonding portion and the contact portion and causes the projection to exhibit a spring characteristic when the contact portion is pressed by the driven member.
    Type: Application
    Filed: March 21, 2011
    Publication date: September 29, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yuki Oda, Shinji Yamamoto, Akio Atsuta
  • Patent number: 7732757
    Abstract: An optical encoder equipped with an origin detection apparatus has a scale provided with an optical grating, a plurality of light receiving elements that is provided in association with the pitch of the optical grating and movable relative to the scale and a light source that illuminates the light receiving elements with light through the scale. An optically discontinuous portion is provided in the optical grating of the scale, a change of a light beam that occurs over a certain length of section at the time when a light beam corresponding to the discontinuous portion is incident on the light receiving elements, a change occurring in that section is detected, calculation is performed, and an origin position is detected from the result of the calculation.
    Type: Grant
    Filed: August 18, 2008
    Date of Patent: June 8, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akio Atsuta, Masahiko Igaki
  • Patent number: 7701116
    Abstract: Provided are a motor driving method, a program therefor, and a motor driving apparatus which can shorten starting time of a vibration wave motor. A driving circuit of the vibration wave motor includes a control unit. The control unit controls two-phase driving voltages applied to an electro-mechanical energy conversion element of the vibration wave motor. The control unit controls a phase difference between the two-phase driving voltages to drive a driven member at a predetermined speed in a fixed state of frequencies of the two-phase driving voltages. In this case, when the phase difference is set outside a predetermined range, the control unit changes the frequencies of the two-phase driving voltages.
    Type: Grant
    Filed: October 30, 2006
    Date of Patent: April 20, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventor: Akio Atsuta
  • Patent number: 7622698
    Abstract: A reflective sensor is disclosed which prevents divergent light from a light source from being totally reflected by an interface between the package and the outside thereof and entering a light-receiving element without using a light-shield means and which allows an improved S/N ratio and reduced variations in performance. The reflective sensor includes a light-emitting element and a light-receiving element which are provided on a surface, and a light-transmissive member which covers the light-emitting element and the light-receiving element. The light-receiving element includes a light-receiving region which is spaced from the light-emitting element along the surface, and which light-receiving region is closer to the light-emitting element than an area on the surface that would be illuminated by unimpeded light rays which are totally reflected by an interface between the light-transmissive member and the outside thereof and are directed toward the light-receiving element.
    Type: Grant
    Filed: July 6, 2007
    Date of Patent: November 24, 2009
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masahiko Igaki, Akio Atsuta
  • Publication number: 20090050794
    Abstract: An optical encoder equipped with an origin detection apparatus has a scale provided with an optical grating, a plurality of light receiving elements that is provided in association with the pitch of the optical grating and movable relative to the scale and a light source that illuminates the light receiving elements with light through the scale. An optically discontinuous portion is provided in the optical grating of the scale, a change of a light beam that occurs over a certain length of section at the time when a light beam corresponding to the discontinuous portion is incident on the light receiving elements, a change occurring in that section is detected, calculation is performed, and an origin position is detected from the result of the calculation.
    Type: Application
    Filed: August 18, 2008
    Publication date: February 26, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Akio Atsuta, Masahiko Igaki
  • Patent number: 7425697
    Abstract: An optical encoder equipped with an origin detection apparatus has a scale provided with an optical grating, a plurality of light receiving elements that is provided in association with the pitch of the optical grating and movable relative to the scale and a light source that illuminates the light receiving elements with light through the scale. An optically discontinuous portion is provided in the optical grating of the scale, a change of a light beam that occurs over a certain length of section at the time when a light beam corresponding to the discontinuous portion is incident on the light receiving elements, a change occurring in that section is detected, calculation is performed, and an origin position is detected from the result of the calculation.
    Type: Grant
    Filed: September 13, 2007
    Date of Patent: September 16, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akio Atsuta, Masahiko Igaki
  • Patent number: 7391011
    Abstract: In two phases signals (A, B) outputted from a scale or a scale having a discontinuous portion provided in its incidental member to a light receiving portion, a region in which amplitudes of the two phases signals (A, B) are small corresponds to outputs when a reflecting portion lies in the scale in terms of rotation position, and a region in which amplitudes of the two phases signals (A, B) are large corresponds to outputs when a nonreflecting portion lies in the scale in terms of rotation position. An optical encoder for discriminating positions of a reflecting portion and a nonreflecting portion of a scale using a threshold value (L) to detect an absolute position based on a reason that when the signals (A, B) are arithmetically operated by an arithmetic operation processing circuit to obtain a sum of squares of the signals (A, B), change points in the amplitudes of the signals (A, B) are steeply obtained.
    Type: Grant
    Filed: May 25, 2005
    Date of Patent: June 24, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akio Atsuta, Masahiko Igaki
  • Patent number: 7385179
    Abstract: At least one exemplary embodiment is directed to an optical encoder which includes a first diffraction grating having a desired optical effective aperture ratio at an appropriate gap position so as to eliminate and/or reduce high-harmonic components from the light intensity distribution of interference fringes and reduce high-order spatial frequency components overlapped on a displacement signal of the interference fringes formed by the first diffraction grating.
    Type: Grant
    Filed: August 28, 2006
    Date of Patent: June 10, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masahiko Igaki, Akio Atsuta
  • Patent number: 7358865
    Abstract: An optical encoder includes a cylindrical reflective scale, a point light source for irradiating the reflective scale, and light-receiving elements for receiving the light beams reflected by the reflective scale. The pitch of the reflective scale is set to an appropriate value such that the pitch of interference fringes formed by light beams that are reflected by the reflective scale is matched to the pitch of the light-receiving elements at a position with a desired gap.
    Type: Grant
    Filed: August 28, 2006
    Date of Patent: April 15, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masahiko Igaki, Akio Atsuta
  • Publication number: 20080073493
    Abstract: An optical encoder equipped with an origin detection apparatus has a scale provided with an optical grating, a plurality of light receiving elements that is provided in association with the pitch of the optical grating and movable relative to the scale and a light source that illuminates the light receiving elements with light through the scale. An optically discontinuous portion is provided in the optical grating of the scale, a change of a light beam that occurs over a certain length of section at the time when a light beam corresponding to the discontinuous portion is incident on the light receiving elements, a change occurring in that section is detected, calculation is performed, and an origin position is detected from the result of the calculation.
    Type: Application
    Filed: September 13, 2007
    Publication date: March 27, 2008
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Akio Atsuta, Masahiko Igaki
  • Patent number: 7348544
    Abstract: An optical encoder includes a light-emitting unit, a scale with a discontinuous part, and a plurality of light-receiving elements arranged in relationship to a pitch of the scale. In the optical encoder, a light beam from the light-emitting unit reflects off the scale, and is received at the light-receiving elements. As a result of the processing of signals from the light-receiving elements, the discontinuous part is detected and the origin detection can be achieved.
    Type: Grant
    Filed: June 14, 2005
    Date of Patent: March 25, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akio Atsuta, Masahiko Igaki
  • Patent number: 7332708
    Abstract: In an optical encoder, a plurality of light sources is controlled on and off so as to use light rays to irradiate an optical grating of a scale from a plurality of different directions. The light rays are received by a plurality of photoreceptor elements. Operations are performed using signals output from the photoreceptor elements. Accordingly, the relative position between the photoreceptor elements and the scale is detected precisely.
    Type: Grant
    Filed: April 3, 2007
    Date of Patent: February 19, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akio Atsuta, Masahiko Igaki
  • Patent number: 7326919
    Abstract: A main scale of an optical displacement measuring apparatus has slits arranged on it at regular intervals, a part of which is a missing slit that does not allow light to pass through used for detecting the original point. An index scale has four sets of windows formed on it. The four windows are arranged with mutual phase differences of ΒΌ P, where P is the pitch of the arrangement of the slits. When a part of the missing slit overlaps with the index scale, no light reaches to photodiodes from the missing slit and only a partial light flux passes through a window, so that the light quantity decreases. An original point signal associated with the missing slit can be obtained by adding up the outputs of all the photodiodes.
    Type: Grant
    Filed: September 26, 2006
    Date of Patent: February 5, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akio Atsuta, Masahiko Igaki