Disc brake apparatus

摘要

An object is to stably exhibit a two-stage spring characteristic of a plate spring for restraining the generation of a clonk noise in a disc brake apparatus for use in a vehicle. A plate spring 90 for restraining the generation of a clonk noise has a fixture portion 91 having a shape resembling the squarish letter U and elastically fixed to a back plate 61, and an extension portion 92 extending continuously from the fixture portion 91. The extension portion 92 includes an engagement subportion 92a engaged with a support member at all times; a curved subportion 92b located between the engagement subportion 92a and the fixture portion 91; and a contact-engagement subportion 92c located between the curved subportion 92b and the fixture portion 91. The contact-engagement subportion 92c is located a predetermined distance away from the back plate 61 when the back plate 61 is at a non-braking position, and is elastically deformed together with the curved subportion 92b and comes into surface contact with the back plate 61 in a nonslip manner when the curved subportion 92b is elastically deformed by a predetermined amount from its non-braking condition as a result of the back plate 61 moving from the non-braking position toward the rotor-rotation trailing side and thus toward the support member.

主权项

1. A disc brake apparatus comprising:
a disc rotor which can rotate forward and in reverse unitarily with a wheel; a support member to be attached to a vehicle body; a pair of brake pads disposed in such a manner as to be able to grip the disc rotor therebetween and attached to the support member in such a manner as to be movable in an axial direction of the disc rotor and in a circumferential direction of the disc rotor; pressing members for pressing back plates of the brake pads toward the disc rotor; a plate spring which intervenes between the support member and an end portion of the back plate of each brake pad with respect to the circumferential direction of the disc rotor, the end portion being located on a rotor-rotation trailing side at the time of forward rotation of the disc rotor, and which urges the brake pad toward a rotor-rotation leading side at the time of forward rotation of the disc rotor; in braking, the pressing members pressing the brake pads toward the disc rotor, whereby linings of the brake pads are slidably pressed against braking surfaces of the disc rotor for braking rotation of the disc rotor; the plate spring has a fixture portion fixed to the back plate, and an extension portion which extends continuously from the fixture portion; and the extension portion comprising:
an engagement subportion engaged with the support member at all times;a curved subportion located between the engagement subportion and the fixture portion;a contact-engagement subportion which is located a predetermined distance away from the back plate or the fixture portion when the back plate is at a non-braking position, and comes into surface contact with the back plate or the fixture portion in a nonslip manner when the curved subportion is elastically deformed by a predetermined amount from its non-braking condition as a result of the back plate moving, at the time of reverse rotation of the disc rotor, from the non-braking position toward the rotor-rotation trailing side and thus toward the support member; andwherein the contact-engagement subportion is spaced apart from the engagement portion and possesses an end adjoining the fixture portion.