Percussion tool
AssigneeHitachi Koki Co., Ltd.
InventorsAtsuyuki Kikuchi, Sinki Ohtsu, Mutsuo Harada, Akihisa Yahagi
Life of this patent
Estimating the term…
Abstract
A hammer holder, provided between a retainer sleeve and a cylinder, slidably holds an intermediate member in an axial direction. A predetermined clearance is maintained between the hammer holder and the retainer sleeve. The hammer holder has a recessed portion which is engageable with a flange of the intermediate member so as to restrict the slide movement of the intermediate member. A cushioning member receives a percussion force when the flange is stopped by the recessed portion. The clearance restricts a compression amount of the cushioning member so that a predetermined life of the cushioning member is assured.
Claims7
A percussion tool comprising:
- a striking member reciprocating in a cylinder in responsive to a driving force given from a motor;
- an intermediate member struck by said striking member;
- a tool bit provided at a front end of said percussion tool and struck by said intermediate member;
- a retainer sleeve for holding said tool bit so as to be slidable in an axial direction thereof;
- a hammer holder provided between said retainer sleeve and said cylinder for slidably holding said intermediate member in an axial direction thereof, so that a predetermined clearance is maintained between said hammer holder and said retainer sleeve;
- a recessed portion of said hammer holder engageable with a flange of said intermediate member so as to restrict the slide movement of said intermediate member;
- and
- a cushioning member for receiving a percussion force when said flange is stopped by said recessed portion.
A percussion tool comprising:
- a retainer sleeve for holding a tool bit so as to be slidable in an axial direction thereof;
- a front cover holding said retainer sleeve and fixed to a tool body;
- a first hammer holder slidably guided by said front cover and receiving a rebound force transmitted from an intermediate member;
- a second hammer holder engaged with said first hammer holder and having a recessed portion formed on an inside surface thereof for restricting an axial forward shift movement of said intermediate member;
- said intermediate member slidably held by said retainer sleeve and said second hammer holder;
- a cushioning member interposed between said front cover and said second hammer holder for receiving a percussion force transmitted from said intermediate member in a non-loaded condition;
- and
- a clearance provided between a front end of said second hammer holder and a rear end of said retainer sleeve for regulating a deformation amount of said cushioning member.
Dependencies are inferred from the claim text.