Abstract: A reclining device for vehicle seats having a structure capable of reliably maintaining a seat back locking state for preventing the seat back from being undesirably moved on the seat cushion is disclosed. The reclining device includes a base plate, an arm plate, a central shaft, a cam, a pair of locks, a guide plate, an action spring, a return spring, and an actuating lever. The central shaft has a first angled part provided on an intermediate portion of the central shaft and a second angled part provided on an end of the central shaft. The cam has a through hole, a main cam heel and a pair of subsidiary cam heels. Each lock has a main lock heel, a pair of subsidiary lock heels, and a guide protrusion provided on a surface of the lock in a direction parallel to an axis of the central shaft.

Abstract: Disclosed herein is a reclining device for vehicle seats which has a structure capable of reliably maintaining a seat back locking state when a seat back of a vehicle seat is not reclined, thus preventing the seat back from being undesirably moved on the seat cushion, thereby providing a smooth comfortable ride. The reclining device includes a base plate, an arm plate, a central shaft, a cam, a pair of locks, a guide plate, an action spring, a return spring, and an actuating lever. In the reclining device, the central shaft has a first angled part which is provided on an intermediate portion of the central shaft so that an inner end of the action spring is fitted over and fastened to the first angled part, and a second angled part provided on an end of the central shaft. The cam has a through hole, a main cam heel which is provided on each of diametrically opposite sides of the cam, and a pair of subsidiary cam heels which is provided on opposite sides of the main cam heel.