1. Field of the Invention
The present invention relates to an engaging device capable of engaging/disengaging two members as well as a transfer instrument employing the engaging device.
2. Description of the Related Art
Hitherto, wide use has been made of an engaging device structured to engage one member with another by means of a claw capable of engaging such members. Specifically, such an engaging device includes engaging components provided on respective of the two members, the engaging components having respective engaging surfaces. The engaging device is configured such that the two engaging components can take an engaging position in which the two engaging surfaces face each other and an open position in which the two engaging surfaces are spaced apart from each other switchably. Particularly, the engaging device is configured such that the two engaging components take relatively retracted positions temporarily in the course of moving from the engaging position to the open position or vice versa (see the following patent documents 1 and 2 for example).    Patent document 1: Japanese Utility Model Publication No. HEI 7-18676 (FIG. 1 and the like)    Patent document 2: Japanese Patent No. 3459686 (FIG. 1 and the like)
However, in cases where the aforementioned engaging device is used in such a manner that the engaging position and the open position are frequently switched to each other repeatedly, the user may feel tired of performing an operation for releasing the engaging components from the engaging position. Further, it is possible that the claw is damaged by the user trying to release the engaging components kept engaged from the engaging position forcibly due to being oblivious of conducting the operation of releasing the engagement.
In view of such an inconvenience the present invention intends to provide an engaging device capable of advantageously releasing the engaging components from the engaging position as well as a transfer instrument employing the structure of such an engaging device to allow the user to use the transfer instrument conveniently.