US 6,000,888 A · Quick coupler mechanism for power tool bits

Abstract

A pneumatic impact power tool has a tool body with a bit-receiving axial bore in its end surface. A cap is threaded on the end of the tool body and has an end wall spaced from the end surface to define a cavity and a lobed opening in the cavity matably receiving a like-lobed bit shank, the cavity being dimensioned to accommodate the lobes. Spring-biased balls project into the cavity from radial bores in the end cap to engage the shank lobes and bias them to a rotational position non-aligned with the opening lobes to inhibit removal. The cavity is dimensioned to afford a slight axial clearance to accommodate axial movement of the lobes. A cover on the end cap is recessed to receive the bias springs, retaining both the springs and the cover in place. The end cap has a annular channel communicating with an exhaust passage in the tool body and four exhaust ports in the end wall.

Claims23

Dependent claims

A quick coupling mechanism for a power tool comprising:

a tool housing having an end wall with an opening therethrough, the opening having plural first lobes;
a tool bit with a shank having a longitudinal axis and plural second lobes arranged so that said shank is receivable axially in and removable axially from said opening in a first rotational orientation with said second lobes respectively axially aligned with said first lobes,
said shank being receivable in said opening to an inserted position wherein said second lobes are disposed inwardly of said end wall;
and
a bias mechanism operable when said second lobes are in said inserted position for engaging said second lobes and resiliently urging said second lobes and said shank circumferentially to a latched condition in a second rotational orientation with said second lobes out of axial alignment with said first lobes and cooperating with said end wall to inhibit removal of said shank from said housing.

2 more elements

A quick coupling mechanism for a power tool comprising:

an elongated tool body having an end surface with an axial bore formed therein;
an end cap having a side wall secured to the tool body and an end wall spaced axially from said end surface for cooperation therewith to define a cavity,
said side wall having a plurality of circumferentially spaced radial bores therein communicating with said cavity and said end wall having formed therethrough an opening with plural first lobes communicating with said cavity;
a tool bit with a shank having plural second lobes arranged so that said shank is receivable axially in and removable axially from the axial bore in a first rotational orientation with said second lobes axially aligned with said first lobes,
said shank being receivable in said bore to an inserted position wherein said second lobes are disposed in said cavity;
and
a plurality of bias assemblies respectively disposed in said radial bores and projecting into said cavity and operable when said second lobes are in said cavity for resiliently urging said second lobes to a latched condition in a second rotational orientation with said second lobes out of axial alignment with said first lobes and cooperating with said end wall to inhibit removal of said shank from said housing;
and
a cover on said end cap overlying said radial bores for retaining said bias assemblies therein.

6 more elements

Dependencies are inferred from the claim text.

Quick coupler mechanism for power tool bits

Life of this patent

Quick coupler mechanism for power tool bits

Life of this patent

Abstract

Claims23