Microtech Laboratory Co., Ltd. | Precision Rotary Encoders & μDD Direct Drive Motors

Hollow Shaft Encoder Mounting

A compact and clean direct-to-shaft mounting method for high-precision rotary measurement.

Shaft Type Encoder Setup

A flexible installation option for coupling-based measurement when direct hollow shaft mounting is not suitable.

Find by Shaft Shape and Measurement Method

Measure by Direct Shaft Mounting
Hollow Shaft Type
MEH, MAH Series

Enables high-precision rotary measurement. Ideal when installation space is limited.

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Simplify Hollow Shaft Installation
Set Screw Fixed Type

Direct mounting to the machine shaft with set screws enables easy, high-precision, space-saving rotary measurement.

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Measure Rotation with a Coupling
Shaft Type
MES, MAS Series

Choose the best model from a wide range of resolutions, outer diameters, and shaft lengths. Couplings are also available as an option.

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Measure by Pressing a Roller Against the Target
Roller Encoder Series

Using a roller with a 200 mm circumference, length measurement is possible with resolutions from 1 mm to 0.1 mm.

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Digital Linear Measurement for Retrofit Applications
Wire Encoder Series

No linear guide rail is required, making stroke measurement easy. Digital display is also possible when used with a counter.

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Watch the Hollow Shaft Encoder Mounting Method, MEH, MAH

Mounting Procedure

Attach the spring flange to the encoder
Mount the optional spring flange to the PCD mounting holes on the encoder base using the included flat-head screws, washer A, and washer B.
Insert the encoder onto the measured shaft
Machine the measured shaft with a stepped section and a male thread at the tip, then insert the encoder so that the hollow shaft end face contacts the stepped surface.
Clamp and secure the rotating shaft with a nut
Clamp the hollow shaft in the thrust direction using a nut.
Before fully tightening, rotate the encoder shaft lightly and tighten it at the position with the least runout.
Fix the spring flange to the machine frame
Finally, use the mounting holes on the outer side of the spring flange to secure it to the machine frame. Screws for fixing to the frame are not included.
When fixing it to the frame, use a spacer of 2.5 mm or more between the spring flange and the frame so that the spring flange does not touch the frame. This is necessary to maintain the flange spring function.

Important Notes for Hollow Shaft Encoder Assembly

Because the spring flange is a flat plate, it is difficult for it to absorb load caused by radial eccentricity. Please keep radial eccentricity to approximately 20 μm or less during rotation.

If radial fluctuation is large, we can also provide a special spring flange.

Important notes for hollow shaft encoder assembly

Advantages of the Hollow Shaft Type

High-precision detection
This hollow shaft design can be mounted directly onto the measured shaft. Unlike shaft encoders, no coupling is required, and the encoder can be mounted in a way that fits the machine. This reduces mechanical error and enables highly accurate reading of shaft rotation.

Space saving
Because it can be mounted directly to the mating shaft, the number of mounting parts can be reduced. Since no coupling is required, axial space can also be saved.

Cost reduction
Simplifying the mechanical structure helps reduce the total machine cost.