花鍵聯(lián)接按齒形的不同，可分為矩形花鍵和漸開線花鍵兩類，這兩類花鍵均已標(biāo)準(zhǔn)化。

矩形花鍵的定心方式為小徑定心，即外花鍵和內(nèi)花鍵的小徑為配合面。其特點是定心精度高，定心的穩(wěn)定性好，能用磨削的方法消除熱處理引起的變形。

The spline connection can be divided into two types: rectangular spline and involute spline. The two kinds of spline are standardized.

The centering way of the rectangular spline is the small diameter centering, that is, the small diameter of the outer spline and the inner spline is the matching surface. It is characterized by high centering precision and good stability of centering. It can be used to remove the deformation caused by heat treatment by grinding.

螺旋副的間隙大，旋轉(zhuǎn)時費力，使用中穩(wěn)定性差。機(jī)用虎鉗開合行程大，螺旋副的運行長度較長，為保證能夠快速裝夾，（金屬加工真不錯）機(jī)用虎鉗螺旋副的螺距較大。較大的螺距意味著較大的螺旋升角，轉(zhuǎn)動單圈進(jìn)給量較大，使用時較費力；較大的螺距需要更大的配合間隙來確保螺旋副的正常使用。

The clearance of the helix pair is large, the rotation is hard and the stability of the use is poor. The machine has large opening and closing stroke, and the operation length of the screw pair is longer. In order to ensure quick clamping, metal machining is good. Larger pitch means larger spiral angle, larger single turn feed and more laborious use. Larger pitch needs more fit clearance to ensure the normal use of screw pair.

裝夾后產(chǎn)品靠近活動鉗口附近容易上翹、抬起，多次裝夾一致性差。傳統(tǒng)機(jī)用虎鉗的螺旋副間隙較大，在使用中會產(chǎn)生較大振幅的振動；而活動座和虎鉗體之間的滑動接觸面較大，采用的間隙也較大。

After the clamping, the product is easy to  and lifted near the movable jaw, and the cistency of the clamping is poor many times. The spiral pair clearance of traditional machine vice is bigger, which will cause large amplitude vibration in use. The sliding contact between movable seat and jaw vice body is larger, and the gap used is bigger.