This mechanism makes the rack pull flatly using the gear,and the rotating sliding block rotates because of touching a corner of the plank,after the sliding block pulls away from the casting,which moves over.
该机构利用齿轮使齿条先做平移抽拔,可转动滑块在抽离铸件后,因碰到支架的一角而转动,实现让位。