Oldham Type Flexible Coupling

MOL-C Clamp Type

Merits

High Torque
Small Eccentric Reaction Force
High Allowable Misalignment
Vibration Absorption

Recipient of the 1991 Ministry of Economy, Trade and Industry Good Design Award
Oldham type flexible coupling
Slippage between hubs and spacer allows high parallel and angular misalignments
Minimized load derived from misalignments on shafts
Simple configuration enables ease of assembly
Excellent electrical insulation
Operational temperature : -20°C~80°C
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	A
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 MOL 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.
We also manufacture a compact oldham type coupling MOS.
Eccentric Reaction Force / Changes in Static Torsional Stiffness Caused by Temperature / Natural Frequency [PDF 111KB]

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)
MOL-16C	16	12.5	29	7	3	5	M2.5	1	MOL16C.dxf	MOL16C
MOL-20C	20	14	33	9	3	6.5	M2.5	1	MOL20C.dxf	MOL20C
MOL-25C	25	16.5	39	11	3.8	9	M3	1.5	MOL25C.dxf	MOL25C
MOL-32C	32	19	45	14.5	4.5	11	M4	2.5	MOL32C.dxf	MOL32C
MOL-40C	40	23	50	17	7	13	M5	4	MOL40C.dxf	MOL40C
MOL-50C	50	27	58	23	8	16	M6	8	MOL50C.dxf	MOL50C
MOL-63C	63	33	71	28	10	21	M8	16	MOL63C.dxf	MOL63C

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)
MOL-16C	6	0.7	1.4	39000	5.8x10^-7	31	1	3	12
MOL-20C	8	1.2	2.4	31000	1.5x10^-6	60	1.5	3	19
MOL-25C	10	2	4	25000	4.4x10^-6	140	2	3	36
MOL-32C	14	4.5	9	19000	1.4x10^-5	280	2.5	3	69
MOL-40C	16	9	18	15000	4.1x10^-5	540	3	3	130
MOL-50C	20	18	36	12000	1.2x10^-4	820	3.5	3	230
MOL-63C	25	36	72	10000	3.7x10^-4	1900	4	3	450

*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.
The operational temperature range for MOL is -20℃~80℃. 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

Catalog Number	RoHS	Stock Bores D₁·D₂
MOL-16C	Compliant
MOL-20C	Compliant
MOL-25C	Compliant
MOL-32C	Compliant
MOL-40C	Compliant
MOL-50C	Compliant
MOL-63C	Compliant

●All products come with cap screws (MOL-C).
●Tolerance on shaft bores of setscrew type coupling is H8.
●Recommended tolerance on shaft diameters is h6 and h7.
●Setscrew type/clamp type and other combination couplings are available on request.
●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].