The present disclosure relates to a method for the automatic determination of the geometrical dimensions of a tool having a machining region in worm thread form, in particular of a grinding worm, wherein in the method: a measurement element is directed to the tool for the detection of a distance, the tool is set into rotation with respect to the measurement element, and a conclusion is drawn on the geometry of the tool on the basis of distance values that were detected by the measurement element during the rotation of the tool.

A threaded shaft measuring device includes a table that supports a threaded shaft to be measured, and that is capable of adjusting a rotation position about a perpendicular Z axis, adjusting a rotation position about an X axis that is horizontal and intersects with the Z axis, and adjusting a position in a Y axis direction that is horizontal and intersects with the X axis; and a stylus that performs scanning measurement of a surface of the threaded shaft. An adjustment jig capable of making contact with the threaded shaft and an elevator that brings the adjustment jig into contact with the threaded shaft are installed on the table. The adjustment jig includes an abutting bottom surface; an abutting side surface; a measurement surface; and an axis line marker that enables a tilt relative to the X axis to be detected.

A method of operating a measurement device to check an internal thread of a spark plug bore for proper orientation of a spark plug includes positioning a cylinder head relative to the measurement device and measuring a seat surface z-position. The seat surface is configured to seat the spark plug within the spark plug bore. The method includes measuring at least one set of coordinates. Each set of coordinates is at a major diameter of a corresponding threadform of the internal thread. The method includes determining a pitch of the internal thread. The method includes calculating a thread start location where the major diameter of the internal thread intersects the seat surface based on the coordinates of the at least one set of coordinates, the pitch of the internal thread, and the z position of the seat surface. The method includes comparing the thread start location to a reference location.

A step gauge includes: measurement blocks each having reference measurement surfaces; interval blocks each interposed between a pair of ones of the measurement blocks to keep a distance between the pair of ones of the measurement blocks at a predetermined distance, the measurement blocks and the interval blocks being alternately aligned one by one in one direction. The measurement blocks and the interval blocks each have a coefficient of linear thermal expansion of less than 0.0310.sup.6(1/K) and have through holes aligned in the one direction. The step gauge further includes a tie rod inserted in the through holes and countersunk screws respectively fixed to ends of the tie rod. The tie rod is made of a material having a coefficient of linear thermal expansion of less than 0.510.sup.6(1/K).

A tool for evaluating a thread depth includes a frame having an elongate portion extending in a first direction; a first contact member coupled to the frame and reciprocable in a second direction between a baseline height and a retracted height, the baseline height being greater than the retracted height. An output device provides an output in response to the height of the first contact member. A reference member is coupled to the frame at a first distance D1 from the first contact member as measured in the first direction; and a second contact member coupled to the frame is disposed at a second distance D2 from the first contact member as measured in the first direction, such that D1 is greater than D2.

A method of operating a measurement device to check an internal thread of a spark plug bore for proper orientation of a spark plug includes positioning a cylinder head relative to the measurement device and measuring a seat surface z-position. The seat surface is configured to seat the spark plug within the spark plug bore. The method includes measuring at least one set of coordinates. Each set of coordinates is at a major diameter of a corresponding threadform of the internal thread. The method includes determining a pitch of the internal thread. The method includes calculating a thread start location where the major diameter of the internal thread intersects the seat surface based on the coordinates of the at least one set of coordinates, the pitch of the internal thread, and the z position of the seat surface. The method includes comparing the thread start location to a reference location.

Provided is a threaded-hole inspection device having high inspection precision. An incomplete thread ridge portion of a gauge portion 5 of a thread gauge 1 is removed, a phase-positioning portion 8 for positioning a tip-side start point 7 of a complete thread ridge at a prescribed phase when the thread gauge 1 is mounted on a rotating-shaft portion 2 is provided to a fastening portion 6 of the thread gauge 1 that is to be fastened to the rotating-shaft portion 2, and a phase-positioning engaging portion 9 that is to engage with the phase-positioning portion 8 is provided to the rotating-shaft portion 2. A depth of a threaded hole 4 to be inspected is measured on the basis of a number of rotations and thread pitch of a rotating-shaft-feeding mechanism 18 that, via threaded engagement, feeds the rotating-shaft portion 2 in a threaded-hole-approaching direction, which is a direction of approach toward the threaded hole 4, the rotating-shaft portion 2 being caused to rotate by a rotary drive portion 3, and on the basis of a distance over which an outward-moving portion 23 moves outward from the threaded hole, and the depth of the threaded hole 4 is calculated.

A method system of reducing operator-induced error in measurements comprises a measurement tool, such as a diameter gage, that is configured to communicate electrical signals representative of measurements to a computing device, which is configured to receive the signals and to determine a value for the measurement without the operator having to interact with the tool to zero the gage, acquire the data or transmit the data.

An assembly for measuring wear of a barrel and feedscrew combination, wherein the barrel has a longitudinally extending feedscrew disposed therein and a radially extending measuring aperture formed in a wall thereof, includes a measuring probe having a proximity detecting sensor, a barrel plug for removable insertion into the measuring aperture, and a measuring fixture. The barrel plug is configured to undergo wear in an axial direction thereof while inserted into the measuring aperture. The measuring probe and the barrel plug are installed into the measuring fixture for determining wear of the barrel plug in the axial direction thereof. The measuring probe is further configured for removable insertion into the measuring aperture for measuring wear of a flight of the feedscrew. A spacer and rotational tool cooperate with the measuring probe when installing the measuring probe in the measuring aperture.

The present disclosure relates to a method for the automatic determination of the geometrical dimensions of a tool having a machining region in worm thread form, in particular of a grinding worm, wherein in the method: a measurement element is directed to the tool for the detection of a distance, the tool is set into rotation with respect to the measurement element, and a conclusion is drawn on the geometry of the tool on the basis of distance values that were detected by the measurement element during the rotation of the tool.