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  • Beam Couplings

Flexible Couplings - Slit Type - Set Screw Type

MST

Safety PrecautionsGlossaryMounting/maintenance

RoHS Compliant

  • Zero Backlash
  • Single-Piece Construction
MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

Dimension Drawing

MSTFlexible Couplings - Slit Type - Set Screw Type寸法図

＊1：　E＝D2(D2＜6)

E＝D2+0.5(D2≥6)

*2: In a case where the bore diameter is φ 4 or less, the set screw is used in only one place.

Specs/CAD

Part Number ALWFM Screw Tightening
Torque (N・m)		Standard Bore Diameter (Dimensional Allowance H8)
D1-D2		 Price
(USD)		 CAD
Download		 Add to Cart Additional Modification
MST-8 8 3.5 14 1.7 M2 0.3 28.00 CAD Cart       
MST-12 12 5 18.5 2.5 M2.5 0.5 28.90 CAD Cart       
MST-16 16 6.5 23 3 M3 0.7 33.23 CAD Cart       
MST-20 20 7.5 26 3 M3 0.7 37.34 CAD Cart       
MST-25 25 8.5 31 4 M4 1.7 42.73 CAD Cart       
MST-32 32 12 41 6 M4 1.7 49.77 CAD Cart       
MST-40 40 17 56 8.5 M5 4 94.66 CAD Cart       
MST-50 50 21 71 10.5 M6 7 153.27 CAD Cart       
MST-63 63 26 90 13 M8 15 226.02 CAD Cart       

Part Number Max. Bore Diameter
(mm)		 Rated
Torque＊1
(N・m)		Max. Rotational Frequency
(min-1)		 Moment of
Inertia
(kg・m2)＊2		Static
Torsional
Stiffness
(N･m/rad)		Max. Lateral Misalignment
(mm)		Max. Angular
Misalignment
(°)		 Max. Axial
Misalignment
(mm)		Mass
(g) ＊2
MST-8 4 0.1 78000 1.2×10-8 25 0.1 2 ±0.2 1.4
MST-12 6 0.4 52000 8.3×10-8 45 0.1 2 ±0.3 3.7
MST-16 8 0.5 39000 3.3×10-7 80 0.1 2 ±0.4 8.1
MST-20 10 1 31000 9.0×10-7 170 0.1 2 ±0.4 14
MST-25 12 2 25000 2.6×10-6 380 0.15 2 ±0.5 27
MST-32 16 4 19000 9.6×10-6 500 0.15 2 ±0.5 60
MST-40 20 8 15000 3.2×10-5 700 0.2 2 ±0.5 130
MST-50 25 16 12000 1.0×10-4 1800 0.2 2 ±0.5 260
MST-63 35 32 10000 3.2×10-4 3100 0.2 2 ±0.5 490

＊1：　Correction of rated torque due to load fluctuation is not required.
＊2：　These are values with max. bore diameter.

Part Number Standard Bore Diameter (Dimensional Allowance H8)
D1･D2
MST-8 2-2 2-3 3-3    
MST-12 3-3 3-4 3-6 4-4 4-5
4.5-5 5-5 5-6    
MST-16 4-4 4-5 4-6 4.5-5 5-5
5-6 5-8 6-6 6-6.35 6-7
6-8 6.35-8      
MST-20 5-5 5-6 5-8 6-6 6-6.35
6-7 6-8 6-10 6.35-8 8-8
8-10 10-10      
MST-25 5-6 6-6 6-6.35 6-8 6-10
6.35-8 6.35-10 8-8 8-10 8-12
9.525-10 10-10 10-12 12-12  
MST-32 6-8 6.35-8 8-8 8-10 8-12
9.525-12 10-10 10-11 10-12 10-14
12-12 12-14 14-14 14-16  
MST-40 8-9.525 10-10 12-12 14-14 15-15
16-16 18-18      
MST-50 12-12 14-14 15-15 16-18  
MST-63 14-14        

● All products are provided with hex socket set screws.
● Recommended tolerance for shaft diameters is h6 and h7.
● Bore additional modification is available on request. Please take advantage of our modification services.
●For the shaft insertion amount to the coupling, see Mounting/maintenance. ⇒Mounting and Maintenance


Part Number
Amount
Price（＄）

Check other products Cart

　　　　　　

Additional Modification Service

Modified Part Number

Enter the desired bore diameter and then click [Check Modified Part Number].

Standard bore diameter(D1) Standard bore diameter(D2) Modified Part Number Price Add to cart

unit:mm
Applicable Bore Diameter
D1D2		 keyway Key
b t Nominal Dimension
b×h
Standard Dimension Allowance
(JS9)		 Standard Dimension Allowance
6 7       2 ±0.0125 1.0 +0.1
0 		2×2
8 9 10     3 ±0.0125 1.4 3×3
11 12       4 ±0.0150 1.8 4×4
13 14 15 16 17 5 ±0.0150 2.3 5×5
18 19 20 22   6 ±0.0150 2.8 6×6
24 25 28 30   8 ±0.0180 3.3 +0.2
0 		8×7
32 35 36 38   10 ±0.0180 3.3 10×8
40 42 44     12 ±0.0215 3.3 12×8
45 48 50     14 ±0.0215 3.8 14×9
55 16 ±0.0215 4.3 16×10

unit:inch
Standard Inch Bore Diameter
D1D2		 Keyway
Wk T
Standard Dimension Allowance Standard Dimension Allowance
1/2 1/8 +0.002
  0		 0.560 +0.01
  0
9/16 1/8 +0.002
  0		 0.623 +0.01
  0
5/8 3/16 +0.002
  0		 0.709 +0.01
  0
11/16 3/16 +0.002
  0		 0.773 +0.01
  0
3/4 3/16 +0.002
  0		 0.837 +0.01
  0
13/16 3/16 +0.002
  0		 0.900 +0.01
  0
7/8 3/16 +0.002
  0		 0.964 +0.01
  0
15/16 1/4 +0.002
  0		 1.051 +0.01
  0
1 1/4 +0.002
  0		 1.114 +0.01
  0
1-1/8 1/4 +0.002
  0		 1.241 +0.01
  0
1-1/4 1/4 +0.002
  0		 1.367 +0.01
  0
1-3/8 5/16 +0.002
  0		 1.518 +0.01
  0
1-1/2 3/8 +0.002
  0		 1.669 +0.01
  0
1-5/8 3/8 +0.002
  0		 1.796 +0.01
  0
1-3/4 3/8 +0.002
  0		 1.922 +0.01
  0

Structure

MSTS-KMade of all stainless steel

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

Set Screws + Key TypeMST-KMSTS-K

MST-KMade of aluminum alloy

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

MSTS-C
Outside diameter φ12 - φ32

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

Clamping TypeMST-CMSTS-C

MST-C Made of aluminum alloy
MSTS-C Made of all stainless steel
Outside diameter φ40 - φ63

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

Set Screw TypeMSTMSTS

MST Made of aluminum alloy
MSTS Made of all stainless steel

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type


Material/Finish

MST
Main Body A2017
Anodized
Hex Socket Head Cap
Setscrew		 SCM435
Ferrosoferric Oxide Film (Black)
Hex Socket Head Cap
Bolt		 SCM435
Ferrosoferric Oxide Film (Black)

Characteristics

  • 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 eccentricity, angular misalignment, and end-play to be accepted.
  • There are two types of units made of aluminum alloy or all stainless steel.
  • Wide variation of outside diameter φ 8 - φ 63.
  • Property
MST MSTS
Zero Backlash ◎ ◎
High Torque ○ ○
High Torsional Stiffness ○ ○
Allowable Misalignment ○ ○
Corrosion Resistance (All S.S.) - ◎

◎: Excellent ○: Very good

  • Applicable motors
MST MSTS
Servomotor ● ●
Stepping Motor ◎ ◎
General-purpose Motor ● ●

◎: Excellent ●: Available


Application

Transport device / XY stage / Parts feeder

Selection

Selection Example

In case of selected parameters of shaft diameter of φ10 and load torque of 1.5 N•m, the selected size forMSTMSTSis MST-25MSTS-25

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

Selection Based on Shaft Diameter and Rated Torque

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

Eccentric Reaction Force

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_TTechnical Information

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_TTechnical Information


Thrust reaction force

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_TTechnical Information

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_TTechnical Information


Change in static torsional stiffness due to temperature

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_TTechnical Information

This is a value under the condition where the static torsional stiffness at 20°C is 100%.
The change of MST and MSTS 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.

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_TTechnical Information


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Product List

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MSX

Part Name

Flexible Couplings - Slit Type - Set Screw Type

Part Number

MSX

Feature

Single-Piece
Construction
Zero Backlash
High Torsional
Stiffness

MSX-C

Part Name

Flexible Couplings - Slit Type - Clamping Type

Part Number

MSX-C

Feature

Single-Piece
Construction
Zero Backlash
High Torsional
Stiffness

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Part Name

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Part Number

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Feature

Single-Piece
Construction
Zero Backlash

MSTS

Part Name

Flexible Couplings - Slit Type - Set Screw Type

Part Number

MSTS

Feature

Single-Piece
Construction
Zero Backlash
High Torsional
Stiffness

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