PURPOSE: To prevent a key device from being damaged by separating the front side opening end surface of a key inserting hole and the head section surface of the key device from each other to a degree so that a key head section may be concealed in the key inserting hole, when a key is inserted into the key device.
CONSTITUTION: A key device 5 is fixed so that its head section may be positioned at a point for the section contained into the side of a vehicle frame 1 by a specified length l from the front side opening end surface of a key inserting hole 3. Then, in a state that a key 8 is inserted into the key device 5, the head section 8a of the key 8 is contrived to be concealed in all in the key inserting hole 3. As a result, when the key of a different diameter except a normal key is inserted into the key device 5, then the key cannot be forcibly turned with excessive torque, and so the key device 5 can be prevented from being damaged.
SUZUKI KAZUHIRO
KANEKO KATSUYOSHI
KAJIWARA KUNIO
