• Couplings
  • Slit Type


Flexible Couplings - Slit Type - Clamping Type

  • Zero Backlash
  • High Torque
  • Single-Piece Construction

Dimension Drawing

MWSS-CFlexible Couplings - Slit Type - Clamping Type寸法図

*1: E=D2(D2<6)



Unit : mm

Part Number A L W F G M Screw Tightening
Torque (N・m)
Standard Bore Diameter
MWSS-12C 12 5.2 14 2.6 4 M2 0.5 CAD RFQ
MWSS-16C 16 6.8 18 3.4 5 M2.5 1 CAD RFQ
MWSS-20C 20 7.65 20 3.8 6.5 M2.5 1 CAD RFQ
MWSS-25C 25 9.6 25 4.8 9 M3 1.5 CAD RFQ
MWSS-32C 32 12.6 32 6.3 11 M4 2.5 CAD RFQ

Part Number Max. Bore Diameter
Max. Rotational Frequency
Moment of
Max. Angular
Max. Axial
(g) *2
MWSS-12C 5 0.3 52000 1.8×10-7 140 1 ±0.1 8.5
MWSS-16C 6 0.5 39000 7.8×10-7 240 1 ±0.1 21
MWSS-20C 8 1 31000 2.1×10-6 330 1 ±0.1 36
MWSS-25C 10 2 25000 6.3×10-6 720 1 ±0.2 69
MWSS-32C 14 3.5 19000 2.2×10-5 1300 1 ±0.2 150

*1: Correction of rated torque due to load fluctuation is not required. For more detailed information, please refer to Selection Guidelines.

※ The shaft's slip torque may be smaller than the coupling's rated torque depending on the shaft bore. MWSMWSSMWS-C

*2: These are values with max. bore diameter.

Part Number Standard Bore Diameter D1・D2
MWSS-12C 4-4 4-5 4.5-5 5-5  
MWSS-16C 4.5-5 5-5 5-6 6-6  
MWSS-20C 5-6 5-8 6-6 6-7 6-8
MWSS-25C 5-6 6-6 6-8 6-10 8-8
8-10 10-10      
MWSS-32C 8-8 8-10 10-10 10-12 12-12

●All products are provided with hex socket set screws.
● In a case where the bore diameter is φ 4 or less, the set screw is used in only one place.
● Recommended tolerance for shaft diameters is h6 and h7.
● Bore and keyway modifications are available on request. Please take advantage of our modification services.

Slip torque

As in the table below, the clamping types MWS-C and MWSS-C have different slip torque according to the bore diameter. Take care during selection.

Unit : N・m

Part Number Bore Diameter (mm)
4 4.5 5 6 8 10 12 14
MWS-25C 3 3.1 3.5
MWSS-12C 0.3 0.4 0.5
MWSS-20C 0.9 1.9
MWSS-25C 1.2 1.4 1.9 3.1
MWSS-32C 1.9 2.4 3.4 4.1

These are test values based on the conditions of shaft dimensional allowance: h7, hardness: 34-40 HRC, and screw tightening torque of the values described in MWS-CMWSS-C dimension tables. They are not guaranteed values.
Slip torque changes with usage conditions. Carry out tests under conditions similar to actual conditions in advance.


Set Screw TypeMWSMWSS

MWS Made of aluminum alloy
MWSS Made of all stainless steel

MWS/MWSS/MWS-C/MWSS-C_CFlexible Couplings - Slit Type

Clamping TypeMWS-CMWSS-C

MWS-CMade of aluminum alloy

MWS/MWSS/MWS-C/MWSS-C_CFlexible Couplings - Slit Type

MWSS-CMade of all stainless steel

MWS/MWSS/MWS-C/MWSS-C_CFlexible Couplings - Slit Type


Main Body SUS303
Hex Socket Set Screw SUSXM7
Hex Socket Head Cap Screw SUSXM7


  • Recommended Applicable Motor
Stepping Motor
General-purpose Motor

◎: Excellent ○: Very good ●: Available

  • Property
Zero Backlash
High Torque
High Torsional Stiffness
Corrosion Resistance (All S.S.) -

◎: Excellent ○: Very good

  • This is a metal spring coupling with single-piece construction. A slit is inserted into a cylindrical material.
  • A plate spring formed by a slit allows angular misalignment, and end-play to be accepted.
  • There are two types of units made of aluminum alloy or all stainless steel.


Transport device / XY stage / Parts feeder

Precautions for Use

In case of mounting on D-cut shaft, be careful about the position of the D-cut surface of the shaft. ⇒Mounting and Maintenance
There are sizes where the hex socket head bolt exceeds the outer diameter of the coupling and the rotating diameter is larger than the outer diameter. Please be careful of the interference of coupling.


Selection Based on Shaft Diameter and Rated Torque

The area bounded by the shaft diameter and rated torque indicates the selection size.

MWS/MWSS/MWS-C/MWSS-C_CFlexible Couplings - Slit Type

MWS/MWSS/MWS-C/MWSS-C_CFlexible Couplings - Slit Type

Selection Example

In case of selected parameters of shaft diameter of φ 5 and load torque of 0.8 N•m, the selected size forMWSMWSSis MWS-20MWSS-20.

Thrust reaction force

MWS/MWSS/MWS-C/MWSS-C_TTechnical Information

MWS/MWSS/MWS-C/MWSS-C_TTechnical Information

Change in static torsional stiffness due to temperature

This is a value under the condition where the static torsional stiffness at 20°C is 100%. The change of MWS and MWSS in torsional stiffness due to temperature is small and the change in responsiveness is extremely small. If the unit is used under higher temperature, be careful about misalignment due to elongation or deflection of the shaft associated with thermal expansion.

MWS/MWSS/MWS-C/MWSS-C_TTechnical Information

MWS/MWSS/MWS-C/MWSS-C_TTechnical Information

Related Products

A slit-type coupling XWSS-C SUS316L material finished with clean washing and clean packaging, which is best suited to FPD and semiconductor manufacturing equipment, is available.

MWS/MWSS/MWS-C/MWSS-C_CFlexible Couplings - Slit Type

Related Service

Product List

Customer Service

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