MOHS-C
Cleanroom / Vacuum / Heat Resistant Coupling – Oldham-Type (VESPEL®) – Clamping Type
Dimension Drawing
Dimensions/Specifications/CAD
| Part Number | A | L | W | E | F | G | M | Wrench Torque (N･m) |
|---|---|---|---|---|---|---|---|---|
| MOHS-19C | 19 | 7 | 22.1 | 10 | 3.5 | 6.5 | M2.5 | 0.5 |
| MOHS-26C | 25.4 | 8 | 27.2 | 14 | 4 | 9 | M3 | 0.7 |
| MOHS-32C | 31.7 | 10 | 33.3 | 18 | 5 | 11 | M4 | 1.2 |
| Part Number | Max. Bore Diameter (mm) | Rated Torque* (N・m) | Max. Torque* (N・m) | Max. Rotational (min-1) | Static Torsional Stiffness (N・m/rad) | Max. Lateral Misalignment (mm) | Max. Angular Misalignment (°) | Mass** (g) |
|---|---|---|---|---|---|---|---|---|
| MOHS-19C | 8 | 0.4 | 0.8 | 900 | 160 | 1.3 | 2 | 28 |
| MOHS-26C | 10 | 1.2 | 2.4 | 900 | 220 | 1.5 | 2 | 61 |
| MOHS-32C | 14 | 2.2 | 4.4 | 900 | 600 | 2 | 2 | 110 |
* Correction of rated torque and max. torque due to load fluctuation is not required.
** These are values with max. bore diameter.
| Part Number | Stock Bores D1-D2 | ||||||
|---|---|---|---|---|---|---|---|
| 5 | 6 | 8 | 10 | 11 | 12 | 14 | |
| MOHS-19C | ● | ● | ● | – | – | – | – |
| MOHS-26C | – | – | ● | ● | – | – | – |
| MOHS-32C | – | – | ● | ● | ● | ● | ● |
All products are provided with hex socket head cap screw.
Recommended dimensional allowances of applicable shaft diameter are h6 and h7.
In case of mounting on D-cut shaft, be careful about the position of the D-cut surface of the shaft.
Material/Finish
| MOHS-C | |
|---|---|
| Hub | SUS303 |
| Spacer | VESPEL＊ |
| Hex Socket Head Cap Screw |
SUSXM7 MoS2 Coating |
＊VESPEL is a registered trademark of U.S. company DuPont.
The color may vary depending on the lot or other matters.
Structure
clamping type
MOHS-C MOHS-C
Characteristics
- Property
MOHS Low Particle △ Vacuum-supported ◎ Less Outgas ○ Heat-resistance ◎ Chemical-proof ○ Allowable Misalignment ◎ Electrical Insulation ◎ Cleanroom Specification ◎ Allowable Operating Temperature -20℃ to 200℃ ◎: Excellent ○: Very good
△: Abrasion powder may be produced - This is an oldham-type flexible coupling.
- Clean washing and clean packaging are completed. It can be used in an environment or cleanroom where heat resistance and chemical resistance are required, such as FPD manufacturing device.
- VESPEL SPC5000 is adopted in the spacer.
This is superior in heat resistance and chemical resistance, and the amount of outgas at high temperature is ultralow. - Slippage of hubs and a spacer allows eccentricity and angular misalignment to be accepted.
- The load on the shaft generated by misalignment is small and the burden on the shaft is reduced.
Application
FPD manufacturing device/Semiconductor manufacturing device
Analysis of outgas
| Component | Content | |
|---|---|---|
| Inorganic gas | Hydrogen | 500 or less |
| Carbon monoxide | 500 or less | |
| Carbon dioxide | 500 or less | |
| Organic gas | Methane | 5 or less |
| Ethane | 5 or less | |
| Ethylene | 5 or less | |
| Propane | 5 or less | |
| Acetylene | 5 or less | |
| i-butane | 5 or less | |
| n-butane | 5 or less | |
| Propylene | 5 or less | |
Both inorganic gas and organic gas are not more than the lower limit of determined amount and are not detected.
- Measurement Methods
Inorganic gas —- Gas chromatography (TCD)
Organic gas —- Gas chromatography (FID) - Measurement Conditions
Heating temperature —- 100℃
Spacer’s projection structure
Spacer’s projection structure allows large angular to be effortlessly accepted. It reduces burden on the shaft.
In the Oldham-type coupling whose spacer has no projection, the spacer and hubs interfere with each other near outside diameter, so that the max. angular misalignment is small (1° – 1.5°) and that the bending moment arises on the shaft.
NBK’s oldham type coupling allows the angular misalignment to be easily accepted since the projection serves as support. Bending moment does not arise. Therefore, the max. angular misalignment is large (2°) and the burden on the shaft is reduced.
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 MOHS in torsional stiffness due to temperature is small and the change in responsiveness is extremely small. However, if the unit is used at higher temperature, be careful about misalignment due to elongation or deflection of the shaft associated with thermal expansion.
Eccentric Reaction Force
These are initial slippage load values of hubs and a spacer.
After running-in operation, the slippage load becomes small, the load on the shaft due to misalignment becomes lowered, and the burden on the shaft bearing is reduced.
