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US 11,007,631 B2Granted
Bit retention assembly for rotary hammer
AssigneeMilwaukee Electric Tool Corporation
InventorsWill Didier, Benjamin J. Ludy
Life of this patent
Estimating the term…
Abstract
A bit retention assembly, for securing a tool bit to a spindle of a rotary hammer, includes a plurality of detent members movable in unison from a locking position to an insertion position in response to insertion of the tool bit within the spindle, a biasing member configured to bias the detent members toward the locking position, and a collar movable along the spindle between a first axial position and a second axial position. The collar has an annular wall at least partially defining a pocket. A first end of the biasing member is received within the pocket when the detent members are in the locking position such that the first end of the biasing member is radially constrained by the annular wall.
Claims18
A rotary hammer adapted to impart axial impacts to a tool bit, the rotary hammer comprising:
- a motor;
- a spindle coupled to the motor for receiving torque from the motor, the spindle including a first retaining groove and a second retaining groove spaced from the first retaining groove;
- a piston at least partially received within the spindle for reciprocation therein;
- an anvil received within the spindle for reciprocation in response to reciprocation of the piston, the anvil imparting axial impacts to the tool bit in response to reciprocation of the piston;
- a bit retention assembly for securing the tool bit to the spindle, the bit retention assembly including
- a plurality of detent members movable rearward in unison from a forwardmost locking position to a rearmost insertion position in response to insertion of the tool bit within the spindle,
- a biasing member configured to bias the detent members toward the locking position,
- a collar movable along the spindle in an axial direction between a first axial position and a second axial position, the collar having an annular wall at least partially defining a pocket, and
- a ring insert molded with the collar such that the ring is fixed within the pocket;
- wherein an inner surface of the ring radially constrains the detent members when the detent members are in the locking position and the collar is in the first axial position;
- wherein a first end of the biasing member is received within the pocket when the detent members are in the locking position such that the first end of the biasing member is radially constrained by the annular wall;
- a first retaining ring received within the first retaining groove of the spindle and engageable with the collar to prevent axial movement of the collar past the first axial position;
- a cap located at a front end of the spindle, the cap including a front portion defining a hole through which the tool bit extends when the tool bit is inserted within the spindle and a rear portion with a projection having a substantially rounded profile in the axial direction;
- and
- a second retaining ring received within the second retaining groove of the spindle, the second retaining ring configured to engage the projection to retain the cap on the spindle,
- wherein the cap is removable from the spindle,
- wherein the first retaining ring is configured to prevent axial movement of the collar past the first axial position when the cap is removed from the spindle, and
- wherein the projection of the cap is positioned between the first retaining ring and the second retaining ring when the cap is retained on the spindle.
15 more elements
A rotary hammer adapted to impart axial impacts to a tool bit, the rotary hammer comprising:
- a motor;
- a spindle coupled to the motor for receiving torque from the motor, the spindle including a first retaining groove and a second retaining groove spaced from the first retaining groove;
- a bit retention assembly for securing the tool bit to the spindle, the bit retention assembly including
- a plurality of detent members movable rearward from a locking position to an insertion position in response to insertion of the tool bit within the spindle,
- a biasing member configured to bias the detent members toward the locking position,
- a collar movable along the spindle in an axial direction between a first axial position and a second axial position, and
- a ring fixed to the collar, wherein an inner surface of the ring radially constrains the detent members when the detent members are in the locking position and the collar is in the first axial position;
- a first retaining ring received within the first retaining groove of the spindle and engageable with the collar to prevent axial movement of the collar past the first axial position;
- a cap located at a front end of the spindle, the cap including a front portion defining a hole through which the tool bit extends when the tool bit is inserted within the spindle and a rear portion with a projection having a substantially rounded profile in the axial direction;
- and
- a second retaining ring received within the second retaining groove of the spindle, the second retaining ring configured to engage the projection to retain the cap on the spindle,
- wherein the cap is removable from the spindle,
- wherein the first retaining ring is configured to prevent axial movement of the collar past the first axial position when the cap is removed from the spindle, and
- wherein the projection of the cap is positioned between the first retaining ring and the second retaining ring when the cap is retained on the spindle.
11 more elements
Dependencies are inferred from the claim text.