ISO 4156-3-2021 pdf free download – Straight cylindrical involute splines — Metric module, side fit — Inspection.
7.1.3.5 Variable sector gauge
The variable sector gauge measures the actual circular tooth thickness or space width.The actualmeasurement is achieved using radially locking left-and right-hand flanks and comparison to a masterhaving a known tooth thickness or space width.
7.1.4 Effective size
7.1.4.1Go composite gauge
Go composite gauges are used to check
a) that the specified effective limits of tooth thickness or space width are not exceeded at themaximum material condition of the part,
b)the specified form diameter of the part, thus ensuring that the required tolerances are controlled
for the full involute depth, and
c) the specified length of engagement, thus ensuring that the spline maximum material limit has not
been exceeded.
7.1.4.2Variable composite gauge
The variable composite gauge measures the effective size of tooth thickness or space width.The actualmeasurement is achieved using the radially locking left- and right-hand flanks and comparison to amaster having a known tooth thickness or space width.
7.1.4.3 NO Go composite gauge
The NO Go composite gauge is used to check the specified effective limit of minimum tooth thickness ormaximum space width, where the gauge contacts only at the ends.
7.1.4.4Inspection of diameter at tooth tip (D, or Dee)
All these inspection methods require measuring the tooth tip (internal minor diameter, D j, or externalmajor diameter, Dp.) using G0 and No GO plain (plug or ring) gauges or other acceptable measuringdevices.
7.2Location7.2.1 General
Splines have an actual and effective true size of space width or tooth thickness, and hence also an actualand effective axis.
The tolerances concerning location (i.e.runout, total runout, concentricity, and coaxiality tolerances)shall be specified on the component drawing. Where the spline is used as a datum axis, other geometryfeatures shall be toleranced to the spline axis.Because of the inherent form deviations, difficultiesarise in the reproducibility and repeatability of the spline profile if the form deviations and cylindricitydeviations are numerous.
7.2.2Choice of the method of inspection of locationThe methods of inspection of location are given in Table 4.
7.2.3 Effective axis using mating part The location of the effective spline axis is defined by the axis of a perfect (without form deviations) mating spline fitting without clearance or looseness. As this is difficult in practice, spline clamping systems or mathematic calculation methods using the individual form deviations derived from analytical inspection may be used.
ISO 4156-3-2021 pdf free download – Straight cylindrical involute splines — Metric module, side fit — Inspection.7.2.4 Actual pitch cylinder axis The location of the actual spline axis (see Figure 3) is defined by the mean centre line of all measured points on the tooth flanks. This axis represents the position at which all deviations are minimum (least- square condition).ISO 4156-3 pdf download.