[werk24]

An involute spline is specified by a standard, for example DIN 5480 - W 40 x 2 x 30 x 18 x 8f. That reads as:

• W: a shaft (a hub is written N);
• 40: the reference diameter;
• 2: the module;
• 30: the pressure angle in degrees;
• 18: the number of teeth;
• 8f: the tolerance class (quality 8, deviation f; a hub's class is in capitals, e.g. 9H).

The older form of the designation leaves out the pressure angle: W 40 x 2 x 18.

What changes

• New model InvoluteSpline (a Feature) with these fields:
  • quantity
  • standard
  • spline_side, which reuses SplineSide (SHAFT / HUB)
  • reference_diameter (Size)
  • module
  • pressure_angle, optional
  • number_of_teeth
  • tolerance_class, optional and kept as written (8f, 9H, 9H/8f)
• ResponseFeaturesComponentDrawing.involute_splines: a new list beside splines. It defaults to empty, so responses from older servers still parse, and older clients ignore it.
• InvoluteSpline is its own model rather than a variant of Spline because the two are sized by different things: straight-sided splines by a count and two diameters, involute splines by a module and a number of teeth.

Tests: five new tests in tests/test_standard_features.py cover:

• a round trip;
• the older form without the pressure angle or the class;
• the bounds on teeth, module and quantity;
• the response round trip;
• a response without the new list.

.venv/bin/python -m pytest on Python 3.13: 1046 passed, 5 skipped (the 5 need credentials).

Questions for the owner

None.

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Generated by Claude Code