Oldham Coupling 43mm
Oldham coupling, 43mm outer diameter, aluminium alloy hubs with a Delrin/Teflon floating disc.
Overview
The TOHC-43 is an Oldham coupling, 43mm outer diameter, for connecting two shafts that aren't perfectly aligned - typically a motor shaft to a leadscrew or ballscrew.
An Oldham coupling works through a floating centre disc with a tongue on each face, set at 90 degrees to each other, sliding in matching slots in the two aluminium alloy hubs. That sliding action absorbs small amounts of parallel and angular misalignment between the shafts without transmitting side-loads into the motor bearing, which a rigid coupling would. The disc itself is Delrin/Teflon, a low-friction plastic that lets it slide freely in the slots.
This design is backlash-free by nature - there's no gear mesh or set-screw play to take up, which matters directly for positioning accuracy on a stepper or servo axis. At this size the coupling suits a larger motor frame than the TOHC-25/TOHC-32, where the shafts themselves are thicker.
Bore size on each hub is matched to the specific motor and leadscrew shafts being connected - confirm both bore diameters fit before ordering.
For a smaller or larger shaft pairing, the TOHC-25/TOHC-32 and the TOHC-53 in this range bracket it in outer diameter.
Supplied by Tiny Controls in India.
Specifications
| Coupling size | 43 mm |
|---|
Questions
I've got a bigger motor with a thicker shaft than the smaller couplings handle — does this size actually suit that?
Yes — at this size it suits a larger motor frame than the TOHC-25/TOHC-32, where the shafts themselves are thicker.
Do I just order this by its 43mm size, or do bore diameters need checking too?
Bore diameters need checking too — bore size on each hub is matched to the specific motor and leadscrew shafts being connected, so confirm both fit before ordering.
Does this design introduce any backlash into the axis?
No — backlash-free by design, no gear mesh or set-screw play to take up.
Where does this sit relative to your other Oldham couplings?
Between the TOHC-25/TOHC-32 (smaller) and the TOHC-53 (larger).
What happens mechanically when the two shafts aren't quite aligned?
The floating center disc, with a tongue on each face set 90 degrees apart, slides in matching hub slots — that takes up small parallel and angular misalignment without side-loading the motor bearing.