一般的钻夹头都要用钥匙来夹紧或松开,但由于转动钥匙时是靠单支点施力,操作费力,弄不好还要滑脱碰伤手,而且钥匙很易丢失。为此,本人设计出了附图所示的自紧钻夹头。它具有:1)结构比普通钻夹头简单,不用钥匙。2)加工容易,工装和工艺基本上与制造普通钻夹头一样。3)使用方便。夹紧时用手将钻头初步夹紧在该钻夹头内,然后开车.当钻头与工件接触时,钻头与三个卡爪间的摩擦力使卡爪与螺杆1上的左螺纹产生转动,迫使三个卡 General drill chuck to use the key to clamp or release, but because the key is rotated by a single pivot force, the operation is laborious, get off but also touch the hand, and the key is very easy to lose. To this end, I designed the self-tightening chuck shown in the attached drawings. It has: 1) The structure is simpler than the ordinary drill chuck, no key. 2) easy processing, tooling and technology is basically the same as making ordinary drill chuck. 3) easy to use. When clamping, the drill bit is initially clamped in the drill chuck by hand, and then the vehicle is driven.When the drill bit and the workpiece are in contact, the friction between the drill bit and the three jaws causes the pawl and the left thread on the screw 1 to rotate, Forcing three cards