Oldham Type Flexible Coupling

MOS

Merits

Small Eccentric Reaction Force
Allowable Misalignment
Vibration Absorption

Oldham type flexible coupling
Compact coupling with short overall length
Slippage between hubs and spacer allows high parallel and angular misalignments
Minimized load on shaft caused by misalignments.
Simple configuration enables ease of assembly
Protruded spacer design enables high allowable angular misalignment
Exhibits excellent electrical insulation
Operational Temperature: -20℃~80℃
Finished products featuring two different end bore diameters available in stock

Application

Servomotor	-
Stepping Motor	B
General-purpose Motor	A
Encoder	-

Features

Zero Backlash	-
High Torsional Stiffness	-
High Torque	B
Absorption of Misalignment	A
Vibration Absorption	B
Electrical Insulation	A
Corrosion Resistant (All Stainless Steel)	-

A : Excellent B : Very Good

The protruded spacer design enables high allowable angular misalignment and minimized load on shafts.
Oldham coupling with no protrusions feature low allowable misalignment (1〜1.5°) due to interference between the spacer and hubs at the proximity of the outside diameter.
A bending moment is generated as well.
The MOS series features a high maximum angular misalignment (3°), enabled by the protrusions which act as points of support.
No bending moment is generated and the shaft load is minimized.
Eccentric Reaction Force / Changes in Static Torsional Stiffness Caused by Temperature / Natural Frequency [PDF 115KB]

Configuration & Material

*Stock screws can be replaced with stainless steel screws. Please take advantage of our stainless steel screw option.
For more information please refer to Stainless Steel Screws [PDF 256KB]

Dimensions

unit:mm
Catalog Number	A	L	W	E	F	G	M	Wrench Torque (N·m)
MOS-8	8	4.8	12.7	4	2.3	-	M3	0.7	MOS8.dxf	MOS8
MOS-12C	12	5	14.9	6	2.5	4	M2	0.5	MOS12C.dxf	MOS12C
MOS-16C	16	7	21	8	3.5	5	M2.5	1	MOS16C.dxf	MOS16C
MOS-20C	20	7	22.1	10	3.5	6.5	M2.5	1	MOS20C.dxf	MOS20C
MOS-25C	25	8	27.2	14	4	9	M3	1.5	MOS25C.dxf	MOS25C
MOS-32C	32	10	33.3	18	5	11	M4	2.5	MOS32C.dxf	MOS32C

Specifications

Catalog Number	Max. Bore (mm)	Rated Torque^* (N·m)	Max. Torque^* (N·m)	Max. Rotational Frequency (min^-1)	Moment of Inertia^** (kg·m²)	Static Torsional Stiffness (N·m/rad)	Errors of Eccentricity (mm)	Errors of Angularity (°)	Mass^** (g)
MOS-8	3	0.08	0.16	78000	1.2x10^-8	2	0.5	2	2
MOS-12C	5	0.2	0.4	52000	7.1x10^-8	9	0.6	2	3
MOS-16C	6	0.4	0.8	39000	3.0x10^-7	30	1	2	8
MOS-20C	8	0.7	1.4	31000	7.4x10^-7	47	1.3	2	13
MOS-25C	10	1.2	2.4	25000	2.2x10^-6	85	1.5	2	24
MOS-32C	14	2.8	5.6	19000	7.3x10^-6	190	2	2	48

*Adjustment of rated and maximum torque specifications for load fluctuations is not required. However, if operating temperature exceeds 30℃, please adjust rated torque and maximum torque as detailed in the table below.
For more detailed information, please refer to Selection Guidelines [PDF 171KB].
**Based on the maximum shaft bores.

Stock Bores

Air Temperature	-20℃~30℃	30℃~40℃	40℃~60℃	60℃~80℃
Temperature Correction Factor	1.00	0.80	0.70	0.55

番	RoHS	Stock Bores D₁·D₂
MOS-8	Compliant
MOS-12C	Compliant
MOS-16C	Compliant
MOS-20C	Compliant
MOS-25C	Compliant
MOS-32C	Compliant

●All products come with setscrews (MOS) or cap screws (MOS-C).
●Tolerance of shaft bore on MOS-8 is H8.
●Recommended tolerance for shaft diameters is h6 and h7.
●Bore and keyway modifications are available on request. Please take advantage of our bore modification services.
For more information please refer to Custom Bore Modifications [PDF 495KB].