Patents Assigned to Mitutoyo Manufacturing Co., Ltd.
  • Patent number: 4733235
    Abstract: A capacitance type displacement measuring instrument is disclosed in which a change in electric capacity between electrodes due to a change in displacement between two members movable relative to each other is detected on the basis of a change in phase of a detection signal and a displacement value between the two members is measured from the change in the capacity. AC signals are successively applied to transmitting electrodes provided on one of the members at a predetermined pitch by a multiplexer and signals induced in transfer electrodes at a predetermined pitch differing from the aforesaid pitch of the transmitting electrodes are received by pickup electrodes provided on the aforesaid one of the members. The relative displacement is detected from a change in phase of a received signal of substantially triangular waveform, which are obtained by the pickup electrode.
    Type: Grant
    Filed: October 26, 1984
    Date of Patent: March 22, 1988
    Assignee: Mitutoyo Manufacturing Co., Ltd.
    Inventors: James A. Baer, Charles B. Clark, Joseph S. Eckerle, Hugh F. Frohbach, Russell T. Wolfram
  • Patent number: 4725720
    Abstract: A microscope comprises:a mount for mounting an object, a light source for illuminating the object, an enlarging optical system including a plurality of objectives provided on a revolver, and means for receiving light from the object to enlargingly form an image of the object. An observing optical system includes an ocular lens for observing said image. The microscope further comprises a magnification selecting unit including a driving mechanism for rotating the revolver, and a magnification selection control circuit for automatically positioning said selected objective to the optical axis of the enlarging optical system. An automatic focus adjusting unit includes a focus detector opposed to the observing optical system for discriminating the enlargedly formed image, and a mount moving device for driving the mount to the position of focus in response to an output signal from the focus detector.
    Type: Grant
    Filed: May 27, 1986
    Date of Patent: February 16, 1988
    Assignee: Mitutoyo Manufacturing Co., Ltd.
    Inventors: Katsuhide Sawada, Hirohiko Shinonaga, Tadashi Satoh
  • Patent number: 4505042
    Abstract: This invention concerns a dimension measuring instrument comprising an encoder for converting a displacement of a spindle into an electric signal and an analogue indication device for electrically indicating a measured value, which has been obtained through processing of an output from the encoder, by a pattern including a scale or scales, a pointer and the like. The analogue indication device is provided with a scale indicating circuit for continuously indicating two or more scales different in scale interval from each other and a pointer indicating circuit for driving the pointer in accordance with the measured value and depending on the scale interval for the indication, and a range of dimension indication is expanded without deteriorating the reading accuracy within a predetermined range of dimension indication.
    Type: Grant
    Filed: April 9, 1984
    Date of Patent: March 19, 1985
    Assignee: Mitutoyo Manufacturing Co., Ltd.
    Inventor: Shingo Nishina
  • Patent number: 4063086
    Abstract: A scale reading apparatus having a dust-proof means for protection of the slide and guide surfaces, the relatively moving parts of the apparatus, from the ingress of foreign material and a means for sensing the scale reading. The dust-proof means includes a flexible band covering the entire length of the slide surfaces and an opening connecting the moving parts. The scale sensing means is resiliently mounted at an angle to the verticle thereby substantially reducing the forces applied and the affects of vibration upon the scale sensing means to insure a high precision reading.
    Type: Grant
    Filed: September 22, 1976
    Date of Patent: December 13, 1977
    Assignee: Mitutoyo Manufacturing Co., Ltd.
    Inventor: Touji Hirose
  • Patent number: 4033175
    Abstract: An apparatus for measuring gas leakage including a hollow container having a gas inlet port which is connected to a reference pressure gas supply via a valve and another gas outlet port that is connected to a test container; a liquid container located in the hollow container, a balance mechanism mounted within the hollow container which is maintained in equilibrium by an inverted floating cup that is attached to the underside of the balance beam and which is immersed in a liquid contained in the liquid container, a supply pipe that introduces gas at a reference pressure into the floating cup, a detector which detects the inclination of the balance mechanism and generates a signal corresponding thereto, a measuring device that measures the displacement of the floating cup as a function of the signal from the detector, and a restoring means that will restore the equilibrium of the tilted balance beam.
    Type: Grant
    Filed: May 11, 1976
    Date of Patent: July 5, 1977
    Assignee: Mitutoyo Manufacturing Co., Ltd.
    Inventors: Takayuki Shiwaku, Takeshi Miyazaki