Patents Assigned to Sigma Koki Co., Ltd.
  • Publication number: 20130201572
    Abstract: An optical element holder includes an optical element holding member that holds an optical element and a body disposed to face to the optical element holding member to support the optical element. The body is provided with a mount portion that mounts the body to a base. The mount portion and the optical element holding member are configured such that the optical element is located on an extension line of a center line of the mount portion.
    Type: Application
    Filed: December 11, 2012
    Publication date: August 8, 2013
    Applicant: SIGMA KOKI CO., LTD.
    Inventor: SIGMA KOKI CO., LTD.
  • Publication number: 20130128273
    Abstract: An optical element (20) is formed by bonding the faces of first to fourth triangular prisms (21, 22, 23, 24) that form the apex angle, wherein bonding faces (21a, 22b) of the first and second triangular prisms, bonding faces (22a, 23b) of the second and third triangular prisms, bonding faces (23a, 24b) of the third and fourth triangular prisms, and bonding faces (24a, 21b) of the fourth and first triangular prisms are respectively bonded through an optical thin film. Each optical thin film allows the incident light to pass through, or reflects the incident light, depending on the polarization state. The optical element (20) splits an optical path at a first position of the optical thin film, and combines optical paths at a second position of the optical thin film.
    Type: Application
    Filed: February 25, 2011
    Publication date: May 23, 2013
    Applicants: HAMAMATSU PHOTONICS K.K., SIGMA KOKI CO., LTD.
    Inventors: Asami Inoue, Kazuya Hirata, Daisuke Ito, Koshi Haraguchi, Shigeru Sakamoto
  • Publication number: 20130068034
    Abstract: A measurement unit for tensile or compressive stress can includes a CCD camera for detecting an interference light, the interference light being formed with a measurement beam from a measured region and a reference beam from a reference mirror. A first objective lens can have the reference mirror. An image processing apparatus can measure the three-dimensional shape of the measured region from the position of the first objective lens at which the interference light provides the maximum contrast and can measure the distance between two gauge points on the basis of the three-dimensional shape. When strain is generated on a micromaterial, the strain against the measured tensile stress is measured on the basis of the tensile stress and the distance between the two gauge points.
    Type: Application
    Filed: June 1, 2011
    Publication date: March 21, 2013
    Applicants: SIGMA KOKI CO., LTD., KUMAMOTO UNIVERSITY
    Inventors: Kazuki Takashima, Masaaki Otsu, Mitsuhiro Matsuda, Hiroaki Kurahara, Hidetaka Maeda, Tadahiro Yonekura
  • Publication number: 20120314269
    Abstract: A piezoelectric actuator mechanism including: a screw-driven feeding mechanism that has a feed screw (11) and a feed screw nut (14); a disc-shaped rotor (17) mounted on the rear-end face of the feed screw nut (14); an ultrasonic motor (18) having a piezoelectric vibrator (19) that comes in contact with the circumference face of the rotor (17); and a driven mounting portion that is pressed against the leading end of the feed screw 11 by spring force, and displaced and positioned by the feeding operation of the feed screw. The driven mounting portion can be made to be a mirror holder (1) for use in an optical system, or a movable table (21) of a linear stage.
    Type: Application
    Filed: January 26, 2011
    Publication date: December 13, 2012
    Applicants: ISHIKAWA PREFECTURE, TOKYO INSTITUTE OF TECHNOLOGY, NIKKO COMPANY, SIGMA KOKI CO., LTD
    Inventors: Masahiro Takano, Kenichi Hirosaki, Ryuji Shintani, Yuta Yoshida, Toshiharu Minamikawa, Kouichi Nakano, Takuya Nagata, Shou Makino, Satoru Ichimura, Takashi Yoshida, Masayuki Ishida, Hiroshi Kawai, Mikio Takimoto, Kentaro Nakamura
  • Publication number: 20120293043
    Abstract: Electrodes (7, 8, 9), having curved sections in the shape of the outline thereof, are disposed in areas of a rectangular plate-shaped piezoelectric transducer element (1) in which the strain in the natural mode of vibration is large. The eletrodes (7, 8) which excite a bending vibration are disposed in areas in which the strain in the bending natural mode is at least a predetermined value, and the outline curved sections of the electrodes (7, 8) are shaped so as to follow along strain contours (3, 4), and the electrode (9) which excites a stretching vibration is disposed in an area in which the strain in the stretching natural mode is at least a predetermined value, thus providing a transducer for an ultrasonic motor which aims to reduce transducer loss (increasing vibration efficiency), and improve transducer durability and reliability.
    Type: Application
    Filed: January 26, 2011
    Publication date: November 22, 2012
    Applicants: ISHIKAWA PREFECTURE, TOKYO INSTITUTE OF TECHNOLOGY, NIKKO COMPANY, SIGMA KOKI CO., LTD
    Inventors: Masahiro Takano, Kenichi Hirosaki, Yuta Yoshida, Takuya Nagata, Shou Makino, Satoru Ichimura, Takashi Yoshida, Masayuki Ishida, Hiroshi Kawai, Mikio Takimoto, Kentaro Nakamura
  • Patent number: 7891877
    Abstract: A circular arc slide apparatus that achieves improved precision and a reduction in costs is provided. The circular arc slide apparatus comprises a lower plate, an upper plate, and a circular arc track provided between the lower plate and upper plate. Guide rail portions are provided in an upper surface of the lower plate and a lower surface of the upper plate, and circular arc curve-shaped guide grooves that constitute the circular arc track are provided in opposing planar surfaces of the guide rail portions. The guide groove cross-section describes a circular arc-shape, and a plurality of balls are rollably fitted between the opposing guide grooves in a preloading state. The lower plate and upper plate are integrally machined from a plate-like material and formed in a shape comprising the guide rail portions and guide grooves, and the inner surface of each guide groove is configured as a machined face produced by an end mill.
    Type: Grant
    Filed: March 19, 2008
    Date of Patent: February 22, 2011
    Assignee: Sigma Koki Co., Ltd.
    Inventors: Kazunori Nomi, Makoto Kadoya, Katsunori Hoshiba, Masaharu Omori
  • Publication number: 20080240640
    Abstract: A circular arc slide apparatus that achieves improved precision and a reduction in costs is provided. The circular arc slide apparatus comprises a lower plate, an upper plate, and a circular arc track provided between the lower plate and upper plate. Guide rail portions are provided in an upper surface of the lower plate and a lower surface of the upper plate, and circular arc curve-shaped guide grooves that constitute the circular arc track are provided in opposing planar surfaces of the guide rail portions. The guide groove cross-section describes a circular arc-shape, and a plurality of balls are rollably fitted between the opposing guide grooves in a preloading state. The lower plate and upper plate are integrally machined from a plate-like material and formed in a shape comprising the guide rail portions and guide grooves, and the inner surface of each guide groove is configured as a machined face produced by an end mill.
    Type: Application
    Filed: March 19, 2008
    Publication date: October 2, 2008
    Applicant: SIGMA KOKI CO., LTD
    Inventors: Kazunori Nomi, Makoto Kadoya, Katsunori Hoshiba, Masaharu Omori
  • Patent number: 5728990
    Abstract: Method and apparatus for machining steel-ball guide grooves in guide rail portions of a linear-motion stage, whose movable member performs linear motions with respect to other movable members. In accordance with this method, first, a lower plate (2), which is an immovable member of the linear-motion stage, and an upper plate (3), which is a movable member thereof, are inserted into a recess portion (25) of a work holding element (21) in such a way that guide rail portions (4 and 5) are faced to each other. Then, the positional relation between the lower plate (2) and the upper plate (3), which are in a fixation state, is established by a pressing unit (31) and a pushing unit (32). Subsequently, a wire is inserted between the guide rail portions. Moreover, the work holding element (21) is caused by a two-dimensional motion device to perform a two-dimensional motion in a horizontal plane.
    Type: Grant
    Filed: October 16, 1996
    Date of Patent: March 17, 1998
    Assignee: Sigma Koki Co., Ltd.
    Inventor: Mitsuo Kobayashi
  • Patent number: 5517363
    Abstract: An optical element holder holds an optical element while minimizing the profile irregularity of the optical element. The optical element holder is provided with three holding portions which abut and engage the peripheral side surface of the optical element at first, second and third positions, respectively. One of the holding portions is movable and can be moved to and away from the peripheral side surface of the optical element, thereby securing the optical element in the optical element holder and releasing the optical element from the optical element holder, respectively.
    Type: Grant
    Filed: February 24, 1995
    Date of Patent: May 14, 1996
    Assignee: Sigma Koki Co., Ltd.
    Inventors: Noboru Suzuki, Mitsuyasu Sho