• Couplings
  • Rigid Type


Rigid Couplings - Clamping Type

  • High-precision
  • Coaxiality 3 μm or less
  • Run out 50 μm or less

Dimension Drawing

XRPRigid Couplings - Clamping Type寸法図

Part Number ALL1WFGM Screw Tightening
Torque (N・m)
Add to Cart
XRP-19C-6-8 19 13 6.5 26 3.5 6.25 M2.5 1 86.68 CAD Cart

Part Number Max. Bore Diameter
Max. Rotational Frequency
Moment of
(g) *2
XRP-19C-6-8 8 2.5 33000 8.0×10-7 15

*1: Correction of rated torque due to load fluctuation is not required. For more detailed information, please refer to Selection Guidelines.
*2: These are values with max. bore diameter.


  • Recommended Applicable Motor
Stepping Motor
General-purpose Motor

◎: Excellent ○: Very good ●: Available

  • Property
Zero Backlash
High Torque
High Torsional Stiffness

◎: Excellent ○: Very good

  • This is a high precision rigid coupling.
  • Coaxiality, bore diameter, and run out have been pursued to the ultimate level.
  • An inspection report is attached to all products before shipment.
  • Light weight and ultra small moment of inertia. High response. High response.
  • This is a shaft fastening structure with consideration of rotational balance and unbalance is ultra small.
  • Extra super duralumin (A7075) featuring the highest strength among aluminum alloy is adopted.


Main Body A7075
Hex Socket Head Cap Screw SCM435
Ferrosoferric Oxide Film (Black)


Clamping Type


XRP_CRigid Couplings


High precision measurement device / High precision XY stage / Encoder

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. Rotation Diameter


Selection Based on Shaft Diameter and Rated Torque

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

XRP_CRigid Couplings

Selection Example

In case of selected parameters of shaft diameter of φ14 and load torque of 9 N・m, the selected size is XRP-39C.

Commitment to high precision

  • The coaxiality of both bores is not more than 3 μm.
  • Bore diameter tolerance is H6.
  • Radial run out and run out of end face against bore are not more than 50μm.

XRP_CRigid Couplings

Precision assurance by total inspection

  • Inspection item:
    Bore diameters D1 and D2
    Coaxiality of bores D1 and D2
    Radial run out and run out of end face against bore

Shaft Insertion Length

The shaft insertion length should be not less than L1 (clamp portion) and not more than L.
The insertion length of a shaft to maintain the high precision should be L dimension if possible.
However, be careful so that both shaft ends do not interfere with each other.
If the shaft insertion length is less than L1, it may derange the coaxiality or generate vibration when fastening the shaft.

XRP_CRigid Couplings

Concentricity tolerance and coaxiality tolerance

Property Symbol Definition of Tolerance Zone
If the symbol φ is attached to the tolerance value, the tolerance zone is regulated by a circle of diameter t. The center of circular tolerance zone coincides with datum A.
If the symbol φ is attached to the tolerance value, the tolerance zone is regulated by a cylinder of diameter t. The axis line of cylindrical tolerance zone coincides with datum A.
Example and explanation of instruction method
The actual (reproduced) center of the outside circle must be within the circle concentric with datum circle A and of 0.1 in diameter.
The actual (reproduced) shaft line of inside cylinder must be within a cylindrical tolerance area coaxial with common datum axis line A-B and of 0.08 in diameter.

Excerpt from JIS B 0021

XRP_CRigid Couplings

XRP_CRigid Couplings

XRP_CRigid Couplings

XRP_CRigid Couplings

Related Services

Product List

Click here to see XRP-19C

Click here to see XRP