PURPOSE: To eliminate risk of slipping-off of screw or its missing and absorb an error in the mounting dimensions by inserting a stepped bushing in a clearance hole for mounting bored in a mounting member, detaining by a collar from the opposite side, and driving with a screw with built-in washer.
CONSTITUTION: A stepped bushing 2 is provided with a stepped hole 2a, which is penetrated by the shank 1a-2 of a screw 1a, in whose major dia. part two washers 1b, 1c and head 1a-1 are intruded, and which is equipped at a part of the hole inlet edge with a projection 2a-1 to be detained so that the intruded flat washer 1c will not slip off, and this 2 is also furnished with a pawl 2a-2 protruding at a part of the foremost periphery of the minor dia. part. A collar 3 is made of plastic material in the form of a circular pipe through molding process and provided with a stepped hole 3a which is to detain the pawl 2a-2 of the intruded bushing 2 with a stepped part 3a-1. From the front surface the bushing 2 is inserted into a clearance hole for mounting 4a which is bored in a cover 4 enclosing the panel 10a surface of a communications device, and detainment is made from the opposite side (rear surface) with the collar 3, and a penetrating screw 1 with built-in washer is driven into a mounting hole 10a-1 in the panel 10a and tightened. Accordingly the arrangement is free from risk of screw slipping-off and missing and can absorb error in the mounting dimensions.
SATO TAKASHI
UMAGOME RIICHI
HONGO TOMOYUKI
YAMAJI HIROSHI
