The present invention addresses the problem of providing a method for measuring axial clearance of a wheel bearing device, with which it is possible to make a high-precision measurement of negative axial clearance. This method comprises: a step (S02) for press-fitting an inner race (4); a first negative axial clearance measurement step (S03); a swaging step (S04); an inner-race press-in amount measurement step (S05); a first inner-race outer-diameter increment measurement step (S06); a second inner-race outer-diameter increment calculation step (S07); an outer-diameter increment difference calculation step (S08); a first axial clearance decrement calculation step (S09); a second axial clearance decrement calculation step (S10); a third axial clearance decrement calculation step (S11); and a second negative axial clearance calculation step (S12).

The present invention addresses the problem of providing a method for measuring axial clearance of a wheel bearing device, with which it is possible to make a high-precision measurement of negative axial clearance. This method comprises: a step (S02) for press-fitting an inner race (4); a first negative axial clearance measurement step (S03); a swaging step (S04); an inner-race press-in amount measurement step (S05); a first inner-race outer-diameter increment measurement step (S06); a second inner-race outer-diameter increment calculation step (S07); an outer-diameter increment difference calculation step (S08); a first axial clearance decrement calculation step (S09); a second axial clearance decrement calculation step (S10); a third axial clearance decrement calculation step (S11); and a second negative axial clearance calculation step (S12).

A method for positioning a body that has a surface extending along a circular arc, includes: attaching the body to a machine part that is capable of swiveling; attaching a stationary, first distance gauge; attaching a stationary, second distance gauge; determining three first distance values and three second distance values at three defined angular positions of the machine part different from each other; calculating a first offset value, based on the three first distance values and the corresponding angular positions, and a second offset value, based on the three second distance values and the corresponding angular positions; shifting the body relative to the machine part, until the first offset value is determined by the first distance gauge and the second offset value is determined by the second distance gauge within permissible tolerances.

A method for positioning a body that has a surface extending along a circular arc, includes: attaching the body to a machine part that is capable of swiveling; attaching a stationary, first distance gauge; attaching a stationary, second distance gauge; determining three first distance values and three second distance values at three defined angular positions of the machine part different from each other; calculating a first offset value, based on the three first distance values and the corresponding angular positions, and a second offset value, based on the three second distance values and the corresponding angular positions; shifting the body relative to the machine part, until the first offset value is determined by the first distance gauge and the second offset value is determined by the second distance gauge within permissible tolerances.

An apparatus for tensioning a fastener while measuring displacement of the fastener relative to a female threaded member may include a driver extension having an interior channel aligned along the extension's central cylindrical axis, open to a socket driver at an output end of the driver. The apparatus may further include a measurement probe in the interior channel, coupled to a measurement indicator on an exterior of the extension by a coupling that moves the measurement indicator in proportion to movement of the measurement probe and a measurement gauge coupled to an exterior of the driver extension that gauges displacement of the measurement indicator. A method for using the apparatus includes driving a female threaded member along a threaded rod by the driver extension while holding the measurement probe against an end of a bolt, screw, or other threaded fastener of which the threaded rod forms a part and while reading the measurement gauge.

An apparatus for tensioning a fastener while measuring displacement of the fastener relative to a female threaded member may include a driver extension having an interior channel aligned along the extension's central cylindrical axis, open to a socket driver at an output end of the driver. The apparatus may further include a measurement probe in the interior channel, coupled to a measurement indicator on an exterior of the extension by a coupling that moves the measurement indicator in proportion to movement of the measurement probe and a measurement gauge coupled to an exterior of the driver extension that gauges displacement of the measurement indicator. A method for using the apparatus includes driving a female threaded member along a threaded rod by the driver extension while holding the measurement probe against an end of a bolt, screw, or other threaded fastener of which the threaded rod forms a part and while reading the measurement gauge.

A gauge inspection jig for performing an inspection easily and accurately in a reverse posture with a contact point facing upward when a gauge is inspected. The gauge inspection jig includes a body portion and a coupling portion. The body portion holds a member mounted to a body portion of the gauge. This holds the gauge in the reverse posture. The coupling portion is coupled to the body portion. The coupling portion is couplable to a distal end of a measurement spindle disposed on a gauge inspector to be movable in a measurement axis direction.

A gauge inspection jig for performing an inspection easily and accurately in a reverse posture with a contact point facing upward when a gauge is inspected. The gauge inspection jig includes a body portion and a coupling portion. The body portion holds a member mounted to a body portion of the gauge. This holds the gauge in the reverse posture. The coupling portion is coupled to the body portion. The coupling portion is couplable to a distal end of a measurement spindle disposed on a gauge inspector to be movable in a measurement axis direction.

A universal tram is provided for aligning machine tools. The universal tram includes a slide rail, featuring a rail along its length, to which a clamping coupler attaches. In turn, the clamping coupler attaches to the indicator holder. The indicator holder is configured to hold an indicator. The slide rail is configured for direct attachment to horizontal and vertical milling machines, for example. Optionally, the universal tram also includes a machine adapter and adapter plate. The machine adapter serves as a base block for positioning a measurement or tramming device on a machine tool to which the slide rail does not directly attach—a horizontal or vertical lathe, for example. The adapter plate allows for the height of the machine adapter to be adjusted by an amount corresponding to the thickness of the adapter plate. Further, a method of using the universal tram is also provided.

There is provided a test indicator 100 capable of replacing a stylus 210 with another stylus 210 having a different length to increase a reaching range of the stylus 210, and of increasing a rotation angle of the stylus 210 to display an accurate measurement value in a wide measurement range.

A calculation unit 400 of the test indicator 100 includes a stylus-length storage unit 420 that sets and stores a length of the stylus 210, and a stylus-length correction calculation unit 400 that changes, according to the length of the stylus 210, a conversion ratio for converting a detection value by an encoder 340 into a measurement value to correct the measurement value. The calculation unit 400 further includes a rotation-angle calculation unit 410 that calculates a rotation angle αs[rad] of the stylus 210 based on the detection value by the encoder 340 and an arc-chord error correction calculation unit 400 that multiplies a sine value using the rotation angle αs calculated by the rotation-angle calculation unit 410 as an argument to correct the measurement value.