The Aluminum Spiral Encoder Coupling with an 8 mm hole diameter is a versatile coupling used for the uninterrupted and angular transmission of rotational motion. It has high torsional rigidity, low restoring forces, a vibration-dampening effect, optimum compensation for misalignment, no moving parts, and is made from a single piece.

It is a low-inertia coupling suitable for high-speed operation due to the high-strength aluminum alloy and the outer diameter of the shaft connection hub.

There are three types of couplings depending on the combination of the inner diameter. When fixing to the shaft, it is possible to securely fix it and shorten the installation time. There are various options available such as special order lengths and keyway milling. Combinations of options are also possible, so you can provide various features.

If your encoder shaft diameter is 10 mm, please continue from here.

Torsional rigidity (spring constant) can be calculated with both the coupling and the stiffness on the shaft for the frequency division number of a feed screw.

The coupling stiffness (kc) combined with the shaft stiffness (ks) for a feed screw on the series-connected axis:

1 / kt = 1 / ks + 1 / kc
ks: stiffness on the screw axis [N · m / rad]
kc: stiffness on the coupling [N · m / rad]
Ji: moment of inertia on the input axis [N · m 2]
Jo: moment of inertia on the output axis [N · m 2]

The frequency division number (Fd) can be calculated from kt and Ji and Jo on the input and output axis with the following steps:

Fd = 0.5 · (1 / π) · {9.8 · kt · (1 / Ji + 1 / Jo)}-2

Please note that our store has three types of encoder coupling models: aluminum spiral, plastic spiral, and steel spiral. The most durable one is the steel spiral model, which has the longest lifespan, does not surprise with unexpected cracks over time, and is the correct choice for heavier loads.