Guide bar fastening device for chain saw
AssigneeMakita Corporation
InventorsYoshiaki TAKAYANAGI, Masashi SUGIYAMA
Life of this patent
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Abstract
To provide an operation lever including a first lever that has a base end portion swingably supported to a peripheral portion of a nut member for fastening a guide bar in a chain saw, and a second lever that is engaged with the first lever in a manner slidable in an axial direction. The operation lever can be placed in a receiving portion of the nut member with an axial length thereof shortened, and can be manipulated to rotate the nut member by being gripped on an outer end portion of the second lever in a state in which the operation lever is lifted out from the receiving portion and the axial length is lengthened. Thus, a sufficient fastening force for the guide bar can be obtained, and operability can be improved.
Claims10
A guide bar fastening device for a chain saw, comprising:
- a guide bar that supports a saw chain on a peripheral portion thereof, one end portion of the guide bar being retained between a chain saw body and a chain cover;
- a bolt member that is secured to the chain saw body and disposed to penetrate through the one end portion of the guide bar and the chain cover;
- a circular nut member that fastens the guide bar by screwing a central portion of the nut member on a screw portion of the bolt member, the screw portion protruding toward an outside of the chain cover;
- and
- an operation lever that includes:
- a first lever that extends in a diametral direction of the nut member, and that has a base end portion that is supported to a peripheral portion of the nut member, so that the first lever is swingable on a plane perpendicular to a rotation plane of the nut member;
- and a second lever that engages with the first lever in a manner slidable in an axial direction, wherein the operation lever is capable of being shortened and lengthened in axial length by a sliding movement of the second lever,
- wherein, in a state in which the axial length is shortened, the operation lever is placed in a receiving portion formed along a radial direction of the nut member, whereas in a state in which the operation lever is lifted out from the receiving portion and the axial length is lengthened outward in the radial direction of the nut member, the operation lever is manipulated to rotate the nut member by being gripped on an outer end portion of the second lever.
Dependencies are inferred from the claim text.