Cam mounting for an impact tool
AssigneeHughes Tool Company
InventorBillie J. Whitworth
Life of this patent
Estimating the term…
Abstract
A motor driven cam and spring impact tool with an improved mounting for the cam. The impact tool includes a driving shaft for rotation relative to the housing. A hammer is positioned in the housing for axial movement with respect to the housing. An annular cam with cam rollers translates the rotational motion of the hammer. A spring urges the hammer in one direction to cause an impact upon each reciprocation. A collar, driven by the shaft, is connected to the cam for rotating it with respect to the rollers. A pair of pins are connected between the cam and the collar for driving the cam. The holes in the cam receiving the pins are enlarged in the direction of rotation to allow the cam to move a selected distance with respect to the pins. This creates backlash at the drop off points on the camming surface.
Claims3
In a motor driven impact tool having a housing, a driving shaft mounted in the housing for rotation relative to the housing, a hammer positioned in the housing for axial movement with respect to the driving shaft, an annular cam with an inclined camming surface, a pair of cooperating cam rollers to translate rotary motion of the driving shaft to reciprocal motion of the hammer, and a spring urging the hammer in one direction to provide an impact, an improved cam mounting comprising:
- a cylindrical collar, having its closed end connected to the driving shaft, its walls encircling the cam and connected to the cam by a pair of pins inserted in apertures formed in the cam transverse to the axis of the driving shaft and spaced apart substantially 180.degree.;
- an axle mounted transverse to one end of the hammer and immovable with respect to the hammer, the cam rollers being mounted on each end of the axle and in contact with the camming surface for causing the hammer to reciprocate as the cam is rotated ;
- the apertures in the cam which the pins are inserted being circumferentially elongated so as to allow the cam to move a selected distance with respect to the pins in a plane substantially normal to the axis of the driving shaft for creating backlash.
In a motor driven impact tool having a housing, a driving shaft mounted in the housing for rotation relative to the housing, a hammer positioned in the housing for axial movement, an annular cam with an inclined camming surface, a cooperating cam roller to translate rotary motion of the driving shaft to reciprocal motion of the hammer, and spring means urging the hammer in one direction to provide an impact, an improved cam mounting comprising:
- transmission means, connected between the driving shaft and the cam, for rotating the cam with respect to the housing, the connection between the transmission means and the cam being a plurality of pins, each pin having one end inserted in a first hole formed in the cam and the other end inserted in a second hole formed in the transmission means;
- an axle mounted transversely and immovably to the hammer, the cam roller being mounted on the axle and in contact with the camming surface for causing the hammer to reciprocate as the cam is rotated;
- one of the holes for each pin being elongated so as to allow the cam to shift with respect to its transmission means in the direction of rotation.
Dependencies are inferred from the claim text.