转辙机是指用以可靠地转换道岔位置，改变道岔开通方向，锁闭道岔尖轨，反映道岔位置的重要的信号基础设备，它可以很好地保证行车安全，提高运输效率，改善行车人员的劳动强度。
作用
(1)转换道岔的位置，根据需要转换至定位或反位；
(2)道岔转至所需位置且密贴后，实现锁闭，防止外力转换道岔；
(3)正确地反映道岔的实际位置，道岔的尖轨密贴于基本轨后，给出相应的表示；
(4)道岔被挤或因故处于“四开”（两侧尖轨均不密贴）位置时，及时给出报警及表示。
Switch machine refers to the important signal equipment used to reliably change the position of the switch, change the opening direction of the switch, lock the switch rail, and reflect the position of the switch.
Effect
(1)Switch the position of the switch to position or reverse as required;
(2)After the switch change to the required position, lock it, and avoid it being converted with the external force;
(3)It correctly reflects the actual position of the switch. The switch's pointed rail is closely attached to the basic rail, and corresponding representation is given.
(4)When the switch is crashed or is in the position of "four open" (two side rails are not closed tightly), the alarm and signal shall be given in time.
