US 12,257,684 B2
Power tool having hammer mechanism
Kiyonobu Yoshikane, Anjo (JP); Yoshitaka Machida, Anjo (JP); Hitoshi Iida, Anjo (JP); and Kazuki Nakagawa, Anjo (JP)
Assigned to MAKITA CORPORATION, Anjo (JP)
Filed by MAKITA CORPORATION, Anjo (JP)
Filed on Nov. 14, 2022, as Appl. No. 17/986,369.
Application 17/986,369 is a division of application No. 17/072,484, filed on Oct. 16, 2020, granted, now 11,529,727.
Claims priority of application No. 2019-192325 (JP), filed on Oct. 21, 2019; application No. 2019-192326 (JP), filed on Oct. 21, 2019; application No. 2019-192327 (JP), filed on Oct. 21, 2019; and application No. 2019-192328 (JP), filed on Oct. 21, 2019.
Prior Publication US 2023/0071871 A1, Mar. 9, 2023
Int. Cl. B25D 16/00 (2006.01); B25D 11/06 (2006.01); B25D 11/10 (2006.01); B25D 17/24 (2006.01)
CPC B25D 16/006 (2013.01) [B25D 11/062 (2013.01); B25D 11/10 (2013.01); B25D 11/102 (2013.01); B25D 16/003 (2013.01); B25D 17/24 (2013.01); B25D 2211/062 (2013.01); B25D 2216/0015 (2013.01); B25D 2216/0038 (2013.01); B25D 2217/0073 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A power tool configured to linearly drive a tool accessory, the power tool comprising:
a piston configured to be linearly reciprocated along a driving axis, the driving axis defining a front-rear direction of the power tool;
a cylindrical tool holder disposed in a front end portion of the power tool and configured to hold the tool accessory to be slidable along the driving axis;
a striking element configured to reciprocate along the driving axis in response to an air spring generated by reciprocating movement of the piston;
an intermediate element disposed between the tool accessory held by the tool holder and the striking element in the front-rear direction, the intermediate element being configured to transmit kinetic energy of the striking element to the tool accessory;
a cylindrical sleeve disposed within the tool holder so as to be slidable in the front-rear direction;
at least one elastic element disposed between the tool holder and a front end surface of the sleeve in the front-rear direction, the at least one elastic element being spaced apart from the intermediate element; and
a stopper disposed behind the sleeve in the front-rear direction,
wherein:
the intermediate element includes a first small-diameter part, a second small-diameter part and a large-diameter part disposed between the first and second small-diameter parts and having a larger diameter than the first and second small-diameter parts,
the sleeve is configured to hold and slidably guide the first small-diameter part of the intermediate element so as to be slidable along the driving axis and to abut on the large-diameter part from the front,
the stopper is configured to hold and slidably guide the second small-diameter part of the intermediate element so as to be slidable along the driving axis and to abut on the large-diameter part from the rear,
an annular gap is defined between an outermost surface of the large-diameter part and the cylindrical sleeve,
the tool holder and the sleeve respectively have a first abutment part and a second abutment part that are configured to abut against each other,
the first abutment part and the second abutment part are configured to be spaced apart from each other in the front-rear direction when a forward force is not being applied to the sleeve, and to abut against each other when a forward force is being applied to the sleeve via the intermediate element, and
at least one of a front end portion and a rear end portion of the at least one elastic element is chamfered.