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US 12,246,428 B2Granted
Striking tool
AssigneeMakita Corporation
InventorsKiyonobu Yoshikane, Mizuki Yamamoto
Life of this patent
Estimating the term…
Abstract
Two balls can reliably retract for smooth insertion of a tip tool into a tool holder. A hammer drill includes a tool holder, two balls in reception holes in the tool holder, a guide washer urging the balls forward in the reception holes with a coil spring, a pressure ring adjacent to a front of the guide washer, and an operation sleeve allowing the pressure ring to move backward and forward between locked and unlocked positions of the two balls. The guide washer includes, on its front surface, a projection toward the pressure ring to cause, with the pressure ring at the locked position, the guide washer to be inclined with respect to an axis of the tool holder for a first ball to move more backward than a second ball.
Claims20
A striking tool, comprising:
- a tool holder being cylindrical and configured to receive a rear end of a tip tool at a front of the tool holder, the tool holder having a pair of reception holes extending radially;
- two balls movable backward and forward in the pair of reception holes in an axial direction of the tool holder, the two balls being movable into and out of an area adjacent to an axis of the tool holder;
- an abutting member being a ring, the abutting member being externally mounted on the tool holder in a manner movable backward and forward;
- an urging member between the tool holder and the abutting member, the urging member urging the two balls forward in the reception holes with the abutting member;
- a pressure ring externally mounted on the tool holder, the pressure ring being movable backward and forward, the pressure ring adjacent to a front of the abutting member, the pressure ring being urged forward by the urging member;
- an operation sleeve externally mounted on the tool holder, the operation sleeve being movable backward and forward between a locked position being forward and an unlocked position being backward,
- at the locked position, the operation sleeve having an inner circumference of the operation sleeve in contact with the pressure ring, the pressure ring being located outside the two balls in front portions of the reception holes to cause the two balls to protrude toward the axis of the tool holder, and
- at the unlocked position, the operation sleeve allowing the pressure ring to move backward from a position outside the two balls to permit the two balls to retract from a protruding position at which the two balls protrude into the tool holder;
- wherein the abutting member includes a projection facing the pressure ring, the projection being configured to cause, with the pressure ring at the locked position, the abutting member to be in an inclined posture with respect to the axis of the tool holder to allow a first ball of the two balls to move more backward than a second ball of the two balls.
6 more elements
A striking tool, comprising:
- a tool holder being cylindrical and configured to receive a rear end of a tip tool at a front of the tool holder, the tool holder having a pair of reception holes extending radially;
- two balls movable backward and forward in the pair of reception holes in an axial direction of the tool holder, the two balls being movable into and out of an area adjacent to an axis of the tool holder;
- an abutting member being a ring, the abutting member being externally mounted on the tool holder in a manner movable backward and forward;
- an urging member between the tool holder and the abutting member, the urging member urging the two balls forward in the reception holes with the abutting member;
- a pressure ring externally mounted on the tool holder, the pressure ring being movable backward and forward, the pressure ring adjacent to a front of the abutting member, the pressure ring being urged forward by the urging member;
- an operation sleeve externally mounted on the tool holder, the operation sleeve being movable backward and forward between a locked position being forward and an unlocked position being backward,
- at the locked position, the operation sleeve having an inner circumference of the operation sleeve in contact with the pressure ring, the pressure ring being located outside the two balls in front portions of the reception holes to cause the two balls to protrude toward the axis of the tool holder, and
- at the unlocked position, the operation sleeve allowing the pressure ring to move backward from a position outside the two balls to permit the two balls to retract from a protruding position at which the two balls protrude into the tool holder;
- wherein the pressure ring includes a projection facing the abutting member, the projection being configured to cause, with the pressure ring at the locked position, the abutting member to be in an inclined posture with respect to the axis of the tool holder to allow a first ball of the two balls to move more backward than a second ball of the two balls.
6 more elements
Dependencies are inferred from the claim text.