Mitutoyo Corporation

Shingo Kuroki

Mikio Suzuki

Souji Ichikawa

Wataru Ishibashi

Yasuo Yamaguchi

Hiroaki Kawada

Hiroomi Honda

Hideki Mishima

Toshiro Horikawa

Ryo Nagai

A surface texture measuring method includes: moving a stylus toward an origin point; and, when the stylus reaches the origin point, braking the stylus to be stopped after overrunning the origin point waiting for a measurement start command (approach section setting operation); bringing the stopped stylus into contact with a target portion of the workpiece (workpiece setting operation); moving the stopped stylus in a measurement direction reverse to the overrunning (approach operation); and, when the stylus passes the origin point in the approach operation, continuing the movement of the stylus while acquiring data detected by the detector (measurement operation).

Surface texture measuring machine and a surface texture measuring method

A stylus abrasion detection method includes obtaining a measurement curve of a standard specimen in which an unevenness that changes periodically is formed on a surface, by causing a stylus to trace along the surface of the standard specimen, detecting a displacement of the stylus in a direction perpendicular to the tracing direction, and using the displacement for obtaining the measurement curve; performing a frequency analysis on the measurement curve; calculating an abrasion amount of the stylus from a result of the frequency analysis; and displaying the abrasion amount calculated by the abrasion amount calculation.

Stylus abrasion detection method and surface property measurement device

An interpolation circuit generates two-phase square wave signals PA and PB from two-phase sinusoidal wave outputs &Oslash;A and &Oslash;B supplied from a photoelectric encoder. A gate signal generator slices a primary origin signal &Oslash;Z supplied from the photoelectric encoder with a predetermined reference level VRef to generate a gate signal Z. A first counter begins to count position pulses generated from the two-phase square wave signals PA and PB when the gate signal Z becomes active. A count value of the first counter is divided by two when the gate signal Z becomes non-active and the divided value is preset into a second counter. The second counter counts the position pulses generated from the two-phase square wave signals PA and PB. A comparator feeds an output origin signal PZ when a count value of the second counter reaches a predetermined offset value N.

Method and apparatus for detecting origin of measurement

A position detector and cable for use in the same can be provided for reducing the space and cost as well as easing maintenance. A scale unit (,) generates an alarm signal (ALAM) for informing of an error when it occurs associated with generating position pulses (PA, PB and PZ). A signal cable (,) transfers the alarm signal (ALAM) to a connector (,). The connector (,) contains an alarm indicator (,) that lights on in response to the alarm signal (ALAM) output from the scale unit (,) when an irregularity occurs.

Position detector with irregularity detectable function and cable for use in the same

A first grating is formed on a main scale, and a second and third gratings on an index scale. The first grating generally assumes a cruciform shape, and consists of a grating having grating lines arranged in the X-direction and another grating having grating lines arranged in the Y-direction. The second grating is formed in a square central area of the index scale, and consists of two gratings having grating lines arranged in the X-direction and divided at the center and another two gratings having grating lines arranged in the Y-direction and divided at the center. The third grating consists of four gratings having grating lines arranged in the X-direction with different phases and another four gratings having grating lines arranged in the Y-direction with different phases. A light-emitting element and eight photodetectors that are arranged corresponding to the respective gratings of the third grating are fixed to a movable member on which the index scale is attached. Light emitted from the light-emitting element passes though the second grating, reflected by the first grating, passes through the third grating, and finally detected by the photodetectors. Alternatively, the first grating may consist of rectangular portions arranged in the X- and Y-direction in a matrix form.

Two-dimensional optical encoder with three gratings in each dimension

In one type of an angular velocity sensor, a constant vibration is applied in an X direction to one end of a vibrator which is fixed at another end and the vibrator vibrates in a Y direction perpendicular to the X direction by an action of Coriolis force caused by the angular velocity of the vibrator about the Z axis with an amplitude proportional to an angular velocity about a Z axis. An angular velocity sensor of this invention utilizes a photoelectric encoder for measurement of the vibration amplitude of the vibrator in the Y direction. The encoder includes a main scale mounted on the free end of the vibrator; an index scale mounted on a housing of the sensor to face the main scale; and a photoelectric element for sensing light reflected from the main scale and passing through the index scale. The angular velocity sensor utilizing the photoelectric encoder is less subject to influence of variation in the temperature in comparison with the conventional sensor utilizing piezoelectric elements and a higher precision can be attained.

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Miyasaki, Japan

Shingo Kuroki