One shaft is fixed and the other is moveable. The variable speed pulley is normally mounted on the moveable shaft and a fixed diameter sheave on the stationary shaft. By using an adjustable motor base, speed variation of the driven shaft is accomplished by mechanically changing the center distance between the shafts. An increase in center distance will pull the belt to a smaller diameter in the variable speed pulley. This increases the drive ratio and reduces the driven shaft RPM. A decrease in center distance allows the spring-loaded pulley faces to close and push the belt to a larger diameter.
Dimensions and Specifications:
| Rated | Pitch | Series | Max. Pitch | Min. Pitch | Belt | Length | Face | Belt | Stock Bore | |
|---|---|---|---|---|---|---|---|---|---|---|
| HP | Ratio | Model | Diameter | Diameter. | Center | Diameter | Size | Sizes | ||
| Single Face Moveable | ||||||||||
| 0.75 | 2:01 | 30 TBR | 3.13 | 1.57 | 0.78 | 2.69 | 3.38 | A | .5•.625•.75 | |
| 1 | 2.5:1 | 40 TBR | 4 | 1.6 | 0.78 | 2.69 | 4.25 | A | .5•.625•.75 | |
| 1 | 3.4:1 | 40TBR-W | 4 | 1.13 | 0.78 | 2.69 | 4.25 | A | 0.5 | |
| 1.5 | 2.7:1 | 50 TBR | 4.65 | 1.72 | 0.78 | 3.19 | 5 | B | .5•.625•.75•.875 | |
| 2 | 2.5: 1 | 57-20 TBR | 5.4 | 2.16 | 0.78 | 3.06 | 5.75 | B | .5•.625•.75•.875 | |
| 3 | 2.5:1 | 57 TBR | 5.4 | 2.16 | 1.09 | 3.88 | 5.75 | B | .75•.875•.625•1•1.125 | |
| 5 | 2:01 | 66 TBR | 6.2 | 3.1 | 1.09 | 3.88 | 6.63 | B | .75•.875•1•1.125 | |
| 5 | 1.6:1 | 86 TBR | 8.28 | 5.17 | 1.09 | 3.88 | 8.63 | B | .75•.875•1•1.125 | |
| Double Face Moveable | ||||||||||
| 1 | 2.3:1 | DCV 140 | 3.75 | 1.63 | 2.19 | 4.38 | 4 | A | .5•.625•.75•.875 | |
| 1.5 | 2.5:1 | DCV 150 | 4.7 | 1.88 | 2.19 | 4.38 | 5 | B | .5•.625•.75•.875 | |
| 1.5 | 3:01 | DCW 1160 | 5.9 | 1.98 | 2.19 | 4.38 | 6.13 | 1422V | .625•.75•.875 | |
| 2 | 2.2:1 | DCV 157-20 | 5.4 | 2.45 | 2.19 | 4.38 | 5.75 | B | .5•.625•.75•.875 | |
| 3 | 2.2:1 | DCV 157 | 5.4 | 2.45 | 2.5 | 4.94 | 5.75 | B | .75•.875•1•1.125 | |
| 3 | 3:01 | DCW 1270 | 7.28 | 2.42 | 2.87 | 5.88 | 7.5 | 1922 | .75•.875•1•1.125 | |
| 5 | 2.5:1 | DCV 167 | 6.5 | 2.6 | 2.88 | 5.88 | 6.88 | B | .75•.875•1•1.125 | |
| 5 | 3:01 | DCW 1590 | 8.75 | 2.9 | 3.53 | 7.06 | 9 | 2322V | 1•1.125•1.25•1.375 | |
| 10 | 3:01 | DCW 1711 | 10.7 | 3.57 | 4.33 | 8.66 | 11 | 3226V | 1•1.125•1.25•1.375 | |
| 20 | 2.5:1 | DCW 2011 | 10.65 | 4.26 | 4.88 | 9.75 | 11 | 3230HV | 1.375•1.625•1.875 | |
| 30 | 3:01 | DCW 2513 | 12.6 | 4.2 | 4.88 | 9.75 | 13 | 4430V | 1.375•1.625•1.875 | |
| Two Groove/Belt | ||||||||||
| 5 | 2:01 | DCV 257 | 5.4 | 2.7 | 3.13 | 6.38 | 5.75 | B (two) | .75•.875•1•1.125 | |
| 7.5 | 1.75:1 | DCV 265 | 6.5 | 3.7 | 3.75 | 7.53 | 7 | C (two) | 1•1.125•1.25•1.375 | |
| Asymmetric | ||||||||||
| 5 | 3:01 | A96 | 9.3 | 3.1 | 1.82 | 6.56 | 9.69 | 23A | Collet No. 512 | |
| 10 | 3:01 | A 112 | 10.8 | 3.6 | 2.32 | 7.25 | 11.25 | 26A | Collet No. 512 | |
| 20 | 2.5:1 | A 112-33 | 10.7 | 4.3 | 2.27 | 7.44 | 11.25 | 33A | Collet No. 512 | |
| 30 | 2.3:1 | A130-33 | 12.4 | 5.4 | 2.52 | 7.44 | 13 | 33A | Collet No. 7713 | |