This invention relates to a clutch device of a fishing reel which has an improved clutch pinion fitted on a spool shaft and provided with a clutch engagement recess releasably engageable with an engagement projection of the spool shaft.
Conventionally, in a dual-bearing type reel, a clutch is provided between a spool shaft and a pinion being in mesh with a drive gear adapted to be rotated by a handle. The pinion is fitted on the spool shaft for movement along an axis thereof so that a clutch engagement recess of the pinion is releasably engageable with a clutch engagement projection of an oval cross-section formed on the spool shaft.
With respect to the clutch engagement recess of the above conventional pinion, as disclosed in Japanese Utility Model Unexamined Publication No. Sho. 55-121670, Japanese Utility Model Examined Publication No. Sho. 59-17174 and Japanese Utility Model Unexamined Publication No. Hei. 1-68777, a transverse groove which defines the engagement recess is formed by milling in a central portion of one end of the pinion in such a manner that shoulder portions of a semi-cylindrical shape remain at the opposite sides of this recess, respectively, and since a sufficient strength is not obtained only with the shoulder portions when the spool shaft and the pinion engaged with each other, a reinforcement ring is fixedly mounted on the outer periphery of the one end of the pinion for reinforcement purposes by fitting and bonding, fitting and soldering, press-fitting, a fitting and compressive deformation, or the like.
However, the impact and the load, produced when an operating condition is switched over from a spool free condition to a winding condition, are exerted on the clutch engagement recess of the pinion, and as a result, drawbacks, such as the increase of the distance between the shoulder portions as a result of the expansion of the reinforcement ring, the shaking of the ring due to a clearance between the outer periphery of the two shoulder portions and the ring, the impairment of the clutch function due to the disengagement of the ring from the shoulder portions, and the generation of abnormal rotation sounds, have been encountered.