Patent ID: 7322768

Claim:
A cover, comprising: a cover body being hard, being formed as a plate shape, comprising opposite surfaces and a socket protruding partially from one of the opposite surfaces, the socket having an inner peripheral surface; a tubular grommet held in the socket, being deformable elastically and being formed of a compressible material, and comprising a fitting hole and an outer peripheral surface, the fitting hole having an inner peripheral surface; and a projection projecting from an installation member to which the cover is installed, and comprising a head, a neck having a diameter smaller than that of the head and an outer peripheral surface, the projection fittable into the fitting hole of the grommet, whereby holding the cover body detachably to the installation member, wherein a diameter of the head of the projection is smaller than a diameter of the socket at a portion of the socket opposite that protruding from the one of the opposite surfaces of the cover body, whereby the head of the projection may be introduced into the socket from a side of the socket opposite the cover body, the grommet further comprising a plurality of convexities having bases disposed on at least one of the outer peripheral surface and the inner peripheral surface of the fitting hole, protruding towards tips thereof in radial directions of the grommet, and contacting with at least one of the inner peripheral surface of the socket and the outer peripheral surface of the projection, wherein the convexities are formed as a substantially triangular cross-sectional shape whose thickness reduces from large to small from the bases to the tips thereof, and wherein the convexities are compressed in the radial directions of the grommet and elastically contact the socket or the projection when the convexities are pressed to an inner peripheral surface of the socket and an outer peripheral surface of the projections, wherein the socket has an inwardly extending flange, and the tubular grommet has an annular groove and is held in the socket by the flange fitted in the annular groove, said grommet being deformable elastically.