Mechanical counter carry

Carry Gear Geometry Lab

Configure the teeth, locking faces, and carry positions. Inspect each working plane and export clean CAD profiles for Fusion.

Calculating geometry
Assembly view preview · Fusion exports are 1:1
Dwell

All levels of one piece, aligned in one sketch with one bore.

Nominal kinematics. Run a cycle check after changing geometry.

Transfer per carryrotation of the compound pinion
Output per carryadvance of the next counter
Carry windowinput rotation per event
Input shaft spacinginput to transfer centre

Dimension schedule

DimensionValueRelationship

Carry positions

EventEntryCentreExit

Design checks

    Geometry for prototyping. This is not a load, wear, friction, or dynamic simulation. Test the axial stack and tooth fit before manufacturing a finished counter.

    Assembly & export notes

    The input teeth and locking disc are one piece. The full transfer gear, scalloped locking plate, and return pinion are a second compound piece. The output gear is the third piece. The return/output mesh runs in a different axial plane from the carry teeth. A coaxial counter stack requires equal input/output centre distances.

    Each SVG contains all levels of one piece, centred on its shaft, with one bore. Different coloured lines distinguish levels in the preview; coincident outlines are included once. Preserve the registered orientation when extruding levels from your sketch.

    The SVG stores circular geometry as arc commands and fitted profiles as compact cubic curves with no sampled polylines. It uses the reference tool's 96-DPI convention; insert it in Fusion at scale 1.0 and measure a known bore. Thicknesses are listed here; the 2D file does not create extrusions.

    Geometry basis & numerical limits

    The layered carry and locking arrangement follows US2881630A. This is a configurable synthesis of that mechanism family, not a dimensional reproduction of the patent drawing. Standard spur-gear relationships follow KHK's gear dimension reference.

    Involute flanks and swept reliefs use adaptive cubic curves at the entered curve tolerance. Circular tips, roots, bores, and locking pockets remain true circular arcs. Entry and exit teeth are relieved against the stationary pinion. The nominal carry uses constant gear ratio during engagement and zero motion in dwell, so transitions imply impact at finite speed. Backlash and release lead create small intervals of free motion.

    The cycle check samples planar interference using the generated profiles. A pass is not a continuous contact, torque, or strength certificate. It does not include out-of-plane features or manufacturing error.

    CNC profile checks

    Each level is checked separately, even when coincident outlines export once. Tooth-tip width is a user-selected feature limit, not a minimum endmill diameter. The input value measures the remaining top land after entry/exit relief; full gears use the top-land chord. Local cutter fit checks the actual exported contours.

    LevelRoot radiusTip widthPitch-circle spaceCutter access

      These are sampled planar checks, not CAM verification. Flute length, when supplied, is compared with each level's thickness only; total reach and access past other levels depend on your extrusion order and setups. CNC principles: internal corner radius and tool access.