| 摘要 |
PURPOSE:To enhance a fixing workability by forming an indentation on the outer periphery of a boss projecting from the one end surface of a gear and a projection on the inner periphery thereof respectively, and by putting said projection into an annular groove formed on the outer periphery at one end of a rotary shaft. CONSTITUTION:In the case of fixing a gear on a rotary shaft, for example in a distributor 1 of an ignition unit for an internal-combustion engine, a rotary shaft 10 is supported rotatably with bearings 8, 9 on the upper and lower opening portion of a cylinder 7 projecting from a lower end surface of a housing body 3. A narrow annular groove 11 is formed on the lower end portion of a first shaft portion 101 of said shaft 10. On the other hand, at least one indentation 15 is formed in plastic deformation with a punch (not shown) having a larger diameter than said groove 11, on the outer periphery of a boss 13 protruding from the upper end surface of a driven gear 12, and a projection 16 is formed similarly on the inner periphery thereof, respectively. By putting said projection 16 into said groove 11, said gear 12 can be fixed immovably in the axial and rotating direction on said shaft 10, thereby facilitating a fixing operation. |
