Safety device and case with lid using safety device

A safety device used for a case with a lid, including the case, the lid openably and closably supported in the case, and a push-push mechanism provided between the case and the lid, locking the lid by a push operation into a closing direction, and releasing a locking of the lid by a next push operation into the closing direction, comprising:

• a lock pin device including a responding moving member adapted to be supported in the case to be displaceable within a predetermined range, urged by a spring in a predetermined direction, and when the case receives an acceleration in a direction reverse to the predetermined direction, generating an inertia force against an urging force of the spring to be displaced in the direction reverse to the predetermined direction, and a lock pin provided to protrude from the responding moving member;
• a lock member adapted to be provided on a lid side, and including a cam groove to receive the lock pin when the lid is positioned in a closed position and the responding moving member is displaced in the direction reverse to the predetermined direction against the urging force of the spring;
• and
• a spring member always urging the lock pin toward the cam groove,
• wherein the cam groove includes:
• at least three first portions adapted to extend in an opening/closing direction of the lid, having an opening-directional side end portion where the lock pin is positioned by a closing-directional movement of the lid and a closing-directional side end portion where the lock pin is positioned by an opening-directional movement of the lid, and mutually disposed in parallel at a predetermined interval therebetween;
• and
• a plurality of second portions connecting the closing-directional side end portion of the first portions and intermediate portions in the opening/closing direction of adjacent first portions,
• a first of the first portions, disposed on the furthest one side among the first portions, where the second portion is not connected to the intermediate portion in the opening/closing direction, receives the lock pin, and a last of the first portions, disposed on the other side among the first portions where the second portion is not connected to the closing-directional side end portion, forms an open end to disengage the lock pin relative to the opening-directional movement of the lid, and
• a depth of a bottom portion of an area between the first portion and the second portion changes so that the lock pin in a state of being received in the cam groove is transferred from the first of the first portions to the last of the first portions non-reversibly cooperating with an urging force of the spring member by a reciprocating movement in the opening/closing direction of the lid.