Belt tensioner for drill press
AssigneeJPW Industries Inc.
InventorBarry M. Schwaiger
Life of this patent
Estimating the term…
Abstract
A drill press has variable speed drive via belts on stepped pulleys that transfer rotational force from the motor to the drill press spindle. Three stepped pulleys connected by two belts are provided in the example. A belt tension roller is bears against one of the belts to provide tension for effective power transfer from the motor to the spindle. The belt tension roller is adjustable along an arcuate slot in an anchor plate and is fastenable in position by an adjustment knob on the belt tension roller. The middle pulley is mounted to vary its position so that tension adjustments on one belt by the belt tension roller result in tension adjustments on the second belt as well.
Claims11
A belt drive for a power tool, comprising;
- a housing;
- a motor mounted connected to the housing, the motor having a motor shaft;
- a first stepped pulley on the motor shaft;
- a first belt on the first stepped pulley;
- a second stepped pulley connected to the first belt to receive rotational energy from the first stepped pulley via the first belt;
- a second belt on the second stepped pulley;
- a third stepped pulley connected to the second belt to receive rotational energy from the second stepped pulley via the second belt;
- a tool connected to the third stepped pulley;
- a belt tension roller configured to bear against one of the first belt and the second belt;
- an offset shaft on which the belt tension roller is mounted, the offset shaft being pivotable in a range of possible positions wherein the range of possible positions include positions bearing against the one of the first and second belts to a greater or lesser extent;
- and
- an adjustment apparatus configured for adjusting a position of the belt tension roller by pivoting the offset shaft and for securing the belt tension roller in a position, the adjustment apparatus includes a user operable control at a first end of the belt tension roller that transmits an engaging force along an axis of the belt tension roller to fasten a second opposite end of the belt tension roller in a selected position to a stationary anchor plate.
A belt drive for a power tool, comprising;
- a housing;
- a motor mounted connected to the housing, the motor having a motor shaft;
- a first stepped pulley on the motor shaft;
- a first belt on the first stepped pulley;
- a second stepped pulley connected to the first belt to receive rotational energy from the first stepped pulley via the first belt;
- a second belt on the second stepped pulley;
- a third stepped pulley connected to the second belt to receive rotational energy from the second stepped pulley via the second belt;
- a tool connected to the third stepped pulley;
- a belt tension roller configured to bear against one of the first belt and the second belt;
- an offset shaft on which the belt tension roller is mounted, the offset shaft being pivotable in a range of possible positions wherein the range of possible positions include positions bearing against the one of the first and second belts to a greater or lesser extent, the offset shaft being pivotable along an arcuate path;
- and
- an adjustment apparatus configured for adjusting a position of the belt tension roller by pivoting the offset shaft along the arcuate path and for securing the belt tension roller in any of a plurality of positions, the adjustment apparatus includes:
- an anchor plate stationarily mounted in the housing, the anchor plate defining an arcuate slot concentric with the arcuate path of the offset shaft;
- a locking bolt extending through the arcuate slot and along an axis of rotation of the belt tension roller;
- and
- an adjustment knob attached to an end of the locking bolt, the adjustment knob being disposed at a first end of the belt tension roller, the adjustment knob being operable to fasten a second end of the belt tension roller to the anchor plate by applying tension along the axis of the belt tension roller.
Dependencies are inferred from the claim text.