Abstract: The measurement apparatus includes an outer cylinder, a shaft body longitudinally movable on the inner surface side of the outer cylinder, a plurality of bearing balls disposed between an inner surface of the outer cylinder and an outer surface of the shaft body, and a measurement part that measures a relative position between the outer cylinder and the shaft body, and a first density of the bearing balls in a first area having a first length shorter than a total length of the outer cylinder in a longitudinal direction from one end of the outer cylinder is larger than a second density of the bearing balls in a second area having a second length shorter than the total length of the outer cylinder centered on a center position in the longitudinal direction of the outer cylinder.

Abstract: The measurement apparatus includes an outer cylinder, a shaft body longitudinally movable on the inner surface side of the outer cylinder, a plurality of bearing balls disposed between an inner surface of the outer cylinder and an outer surface of the shaft body, and a measurement part that measures a relative position between the outer cylinder and the shaft body, and a first density of the bearing balls in a first area having a first length shorter than a total length of the outer cylinder in a longitudinal direction from one end of the outer cylinder is larger than a second density of the bearing balls in a second area having a second length shorter than the total length of the outer cylinder centered on a center position in the longitudinal direction of the outer cylinder.

Abstract: An induction type position measuring apparatus includes a scale and a sensor. The scale includes a track having a plurality of control patterns provided at equal intervals along a measurement reference line to control flow of an induced current, and a first edge portion and a second edge portion located on both sides of the measurement reference line. The sensor is provided to be capable of moving relatively to the scale along the measurement reference line to detect an induced current. The scale includes regulation patterns at least between the track and the first edge portion or between the track and the second edge portion to regulate a flow of an induced current.

Abstract: A linear encoder includes a plate-type scale and a head which moves along the longitudinal direction of the scale. The scale has graduations formed on a surface of the scale and arranged along the longitudinal direction of the scale. The head includes a reading part which detects an amount of a relative movement of the head with respect to the scale by reading graduations formed on the scale. The head includes four bearings each having a rotation axis extending along the transverse direction of the scale. Each of the bearings is situated on the head so as to abut against a surface of the scale, to function as a spacer to maintain a distance between the scale and the head. The scale acts as a plate member interposed between the reading part and the graduations.

Abstract: A micrometer with good usability is provided. A micrometer has a frame with an anvil at one end and a spindle at another end, the spindle moving closer to or further away from the anvil. The frame is covered with a heat shield cover. The heat shield cover has a first anti-slip part. The first anti-slip part preferably has a plurality of protrusions.

Abstract: An induction type position measuring apparatus includes a scale and a sensor. The scale includes a track having a plurality of control patterns provided at equal intervals along a measurement reference line to control flow of an induced current, and a first edge portion and a second edge portion located on both sides of the measurement reference line. The sensor is provided to be capable of moving relatively to the scale along the measurement reference line to detect an induced current. The scale includes regulation patterns at least between the track and the first edge portion or between the track and the second edge portion to regulate a flow of an induced current.

Abstract: A linear encoder includes a plate-type scale and a head which moves along the longitudinal direction of the scale. The scale has graduations formed on a surface of the scale and arranged along the longitudinal direction of the scale. The head includes a reading part which detects an amount of a relative movement of the head with respect to the scale by reading graduations formed on the scale. The head includes four bearings each having a rotation axis extending along the transverse direction of the scale. Each of the bearings is situated on the head so as to abut against a surface of the scale, to function as a spacer to maintain a distance between the scale and the head. The scale acts as a plate member interposed between the reading part and the graduations.

Abstract: A micrometer includes: a frame; an anvil; a spindle; an encoder; a display; a strain gauge that detects a deformation of the frame; a storage that stores a change amount of the detection value (a displacement of the spindle detected by the encoder) per a unit deformation detected by the strain gauge, as a compensation factor; and a compensator that compensates the detection value based on a difference between a zeroset-time deformation that is detected by the strain gauge when a command for zeroset is given and a measurement-time deformation that is detected by the strain gauge in measurement, and based on the compensation factor stored in the storage.

Abstract: A micrometer with good usability is provided. A micrometer has a frame with an anvil at one end and a spindle at another end, the spindle moving closer to or further away from the anvil. The frame is covered with a heat shield cover. The heat shield cover has a first anti-slip part. The first anti-slip part preferably has a plurality of protrusions.

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.

Abstract: A micrometer includes: a frame; an anvil; a spindle; an encoder; a display; a strain gauge that detects a deformation of the frame; a storage that stores a change amount of the detection value (a displacement of the spindle detected by the encoder) per a unit deformation detected by the strain gauge, as a compensation factor; and a compensator that compensates the detection value based on a difference between a zeroset-time deformation that is detected by the strain gauge when a command for zeroset is given and a measurement-time deformation that is detected by the strain gauge in measurement, and based on the compensation factor stored in the storage.

Abstract: A displacement measuring instrument includes a spindle screwed to a stationary sleeve, a thimble, an operation sleeve, and a constant pressure mechanism. The constant pressure mechanism includes: a rotary driving element rotatable together with the operation sleeve; a rotary driven element coupled to the rotary driving element in such a manner as to be rotatable together with the rotary driving element but not to be rotatable when a predetermined or more load is applied to the spindle; and a rotation transmitting mechanism transmitting a rotation of the rotary driven element to the spindle. A male thread portion with the same pitch as that of a male thread portion of the spindle is formed on the outer circumference of the stationary sleeve. A female thread portion is formed on the inner circumference of the thimble and screwed to the male thread portion of the stationary sleeve.

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.

Abstract: Disclosed is a micrometer with an improved a heat-insulating property. A micrometer 10 with a U-shaped frame 20 supporting an anvil 12 and a spindle 14 at tip end portions thereof so that the anvil 12 and the spindle 14 are coaxially opposed to each other is provided with a heat insulating cover 50. The heat insulating cover 50 is shaped to accommodate a bottom portion of the frame 20, and is detachable with respect to the frame 20. The heat insulating cover 50 covers a bottom face 22 of the frame 20 while supporting the bottom portion of the frame 20 by sandwiching from both sides of the frame 20.

Abstract: A displacement measuring instrument includes a spindle screwed to a stationary sleeve, a thimble, an operation sleeve, and a constant pressure mechanism. The constant pressure mechanism includes: a rotary driving element rotatable together with the operation sleeve; a rotary driven element coupled to the rotary driving element in such a manner as to be rotatable together with the rotary driving element but not to be rotatable when a predetermined or more load is applied to the spindle; and a rotation transmitting mechanism transmitting a rotation of the rotary driven element to the spindle. A male thread portion with the same pitch as that of a male thread portion of the spindle is formed on the outer circumference of the stationary sleeve. A female thread portion is formed on the inner circumference of the thimble and screwed to the male thread portion of the stationary sleeve.

Abstract: Disclosed is a micrometer with an improved a heat-insulating property. A micrometer 10 with a U-shaped frame 20 supporting an anvil 12 and a spindle 14 at tip end portions thereof so that the anvil 12 and the spindle 14 are coaxially opposed to each other is provided with a heat insulating cover 50. The heat insulating cover 50 is shaped to accommodate a bottom portion of the frame 20, and is detachable with respect to the frame 20. The heat insulating cover 50 covers a bottom face 22 of the frame 20 while supporting the bottom portion of the frame 20 by sandwiching from both sides of the frame 20.

Abstract: A digital displacement measuring instrument includes a spindle screwed into a body to be axially advanced and retracted relative to the body; and an encoder that detects a displacement of the spindle. The encoder includes a rotor and a stator. The rotor is supported by a rotor bushing. The rotor bushing includes an engaging key engageable with a key groove axially provided on the outer circumference of the spindle, and is displaceable in the axial direction of the spindle via a position adjusting screw. The stator is fixed to the body via a stator bushing in the vicinity of the spindle so as not to be displaceable in the axial direction of the spindle.