Abstract:
PROBLEM TO BE SOLVED: To provide a starter ring gear for a vehicle, which can suppress reduction in hardness of outer circumferential teeth which occurs during welding of a drive plate.SOLUTION: The starter ring gear for a vehicle includes a plurality of circumferential direction grooves 94 formed in the circumferential direction of the other side face 90 to be longer than a welding bead 92, which function as heat resisting parts for suppressing conduction of heat of welding with the drive plate 26 to outer circumferential teeth 44a on, between the inner peripheral surface of the starter ring gear 44 and the tooth surface of the outer circumferential teeth 44a, on a plurality of welding parts with the drive plate 26, namely, on the outer circumferential side of the welding bead 92. Thus, since annealing of the outer circumferential teeth 44a of the starter gear 44 increased in hardness by high-frequency hardening welding of the starter gear 44 and the drive plate 26 is suppressed, reduction in hardness of the outer circumferential teeth 44a near the welding part by welding with the drive plate 26 is suppressed.
Abstract:
PROBLEM TO BE SOLVED: To produce a double-pinion rack bar having two tooth parts without use of a special processing apparatus for formation of the two rack tooth parts.SOLUTION: A rack production apparatus comprises a clamp mechanism 110 supporting a first rack bar 12A formed with a first tooth part in a hollow shank, a chuck mechanism 140 supporting a second rack bar 12B formed with a second tooth part in a solid shank so that the shaft center line C2 of the second rack bar matches the shaft center line C1 of the first rack bar 12A, a table mechanism 120 causing the chuck mechanism 140 to approach the clamp mechanism 110 and a rotation drive portion 130 rotating the chuck mechanism 140 around the shaft center line C2 relative to the clamp mechanism 110.
Abstract:
A method for manufacturing a driving force transmission device for a vehicle having a case and a ring gear that is fitted to the outer peripheral surface of said case and transmits driving force from a drive source, the method being equipped with: a welding process whereby an annular flange is provided on the case or the ring gear and butt welding is performed by lapping a welding bead along the contact portion of one side surface of the annular flange and the case or the ring gear; a measurement process whereby the exterior shapes of the other side surface of the annular flange adjacent to the one side surface are measured; and an assessment process whereby the quality of the weld is assessed on the basis of the shape of the location corresponding to the lapped portion of the welding bead, of the shapes measured in the measurement process.