## What is variable speed belt?

Variable Speed Belts are specified for applications where changes in speed during operation are common. Part of the V-belt family, it differs in shape considerably to the standard v-belt – having a distinctly broader width and a narrower thickness.

### How does a variable speed belt drive work?

The driven pulley is adjustable and the drive pulley is controlled by a mechanical action that will open or close the pulley based on rpm requirement. As the driven pulley is opened, the driven pulley will decrease in speed and the opposite, as the drive pulley is closed the driven pulley will increase in speed.

#### What is a variable speed pulley?

A Variable Speed Pulley is a device for changing the speed of a rotating shaft member, so that it will increase or decrease the revolutions per minute of that particular shaft. The belt used in the pulley has a ‘V’ cross section, where the sides of the ‘V’ conform to the angular faces of the pulley flanges.

How does a variable speed pulley work on a mower?

The variable speed pulley is mounted on a sliding plate, which moves the pulley toward the engine or toward the transmission. As the pulley moves toward the engine, the transmission belt gets tighter. This forces the sliding plate in the variable pulley to squeeze the engine belt.

What do the numbers on a CVT belt mean?

CVT belts are measured in 3 dimensions. For example, here is what the numbers of a 669-80-30 belt actually mean: 669 = The Pitch Length of the belt in millimeters. 18 = The Width of the belt in millimeters. 30 = The Angle of the teeth on the interior of the belt.

## How do you measure a variable speed belt?

The procedure is the same as for V-belts. Measure the upper width of the belt, e.g. 47 mm = profile width 47 mm. Measure the belt thickness, e.g. 13 mm = profile 47 × 13. In the profile table, you can find the appropriate type.

### What does the variation belt do?

This belt then turns the rear drive pulley that makes the mower move at the commanded speed/direction. Or maybe vice versa, but it obviously is the belt that allows the mower to move at different speeds/gears.

#### What is the main difference between a notched belt and a conventional belt?

A notched belt has grooves or notches that run perpendicular to the belt’s length, which reduces the bending resistance of the belt. Notched belts can use the same pulleys as cross-section standard V-belts. They run cooler, last longer, and are about 2% more efficient than standard V-belts.

How do you read a CVT belt size?

CVT belts are measured in 3 dimensions. For example, here is what the numbers of a 669-80-30 belt actually mean:

1. 669 = The Pitch Length of the belt in millimeters.
2. 18 = The Width of the belt in millimeters.
3. 30 = The Angle of the teeth on the interior of the belt.