| 摘要 |
<p>It consists of a system which is incorporated in a support piece in which is coupled the lever which is able to rotate at angles slightly less than 45 degree, being linked via its lower end by means of a common shaft to a special piece which entrains in its displacement and which regulates the advance and withdrawal movement of the lever, likewise intervening in its locking and unlocking. Said special piece has a curvo-convex shape in its lower part, with the result that it is able to act as a stop on a second runner-shaped piece with which it connects upon achieving its maximum displacement.</p> |
