Patent ID: 9429976
Filing Date: 2016-08-30
CPC Classification: G05G,Y10T

Claim Text:
1. A vehicle operation pedal apparatus comprising an operation pedal supported by a pedal support member so as to be pivotable about one axis, and a return spring having one end portion engaged with a bracket plate member disposed on the operation pedal and an other end portion engaged with a position fixing member, the operation pedal being returned by pivoting in accordance with an urging force of the return spring upon cancellation of a depressing operation of the operation pedal, the vehicle operation pedal apparatus further comprising: an engagement hook being formed in the one end portion of the return spring, the engagement hook being one bent end portion of a wire rod that constitutes the return spring, and an engagement hole or cutout into which the engagement hook is hooked being formed in the bracket plate member disposed on the operation pedal so as to pass through the bracket plate member, a surface direction of a portion of the bracket plate member, in which the engagement hole or cutout is formed, being set such that a contact point at which the engagement hook contacts one of a pair of edges that are ridgelines between an inner wall surface of the engagement hole or cutout and one surface and an other surface of the bracket plate member is a relative pivot point about which the return spring pivots relative to the operation pedal in accordance with a pivoting operation of the operation pedal in an entire operation angle range of the operation pedal, an angle between the surface direction of the portion of the bracket plate member, in which the engagement hole or cutout is formed, and a line of action of the return spring, which passes through the contact point, taking a positive value in the entire operation angle range of the operation pedal, or taking a negative value in the entire operation angle range of the operation pedal, an engagement hook being formed in the other end portion of the return spring, the engagement hook formed in the other end portion of the return spring being an other bent end portion of the wire rod that constitutes the return spring, and an engagement hole or cutout into which the engagement hook formed in the other end portion of the return spring is hooked being formed in the position fixing member so as to pass through the position fixing member, wherein one of a pair of edges that are ridgelines between an inner wall surface of the engagement hole or cutout and one surface and an other surface of the position fixing member contacts the engagement hook formed in the other end portion of the return spring, and a curvature radius of an arc-shape of a portion of the engagement hook formed in the other end portion of the return spring, which includes a contact point with respect to the engagement hole or cutout formed in the position fixing member, is larger than a curvature radius of an arc-shape of a portion of the engagement hook formed in the one end portion of the return spring, which includes the contact point with respect to the engagement hole or cutout formed in the bracket plate member.