| 摘要 |
The knife with an extensible and retractable blade has a hollow knife grip and a blade magazine with a plurality of superposed blades therein. With the aid of two entraining members in the form of a pusher bar and two gripper arms of a blade-changing device which slides with the entraining members along two sides of the blade magazine, on pulling the blade-changing device out of the knife grip a used blade is guided by gripper arms back into the blade magazine and on pushing the blade-changing device back into the knife grip, the new blade is pushed out from the blade magazine by means of the pusher bar in the direction towards the front end of the knife and into engagement with a blade-pusher. The blade pusher has a pin arranged at the end of an arm which engages in a hole in the blade. Then with the aid of the blade pusher the blade may be extended to a greater or lesser extent from the knife grip or may be fully retracted into it and arrested in various stop or detent positions. |
