In the past, the position of any point on the NC machine tool is the same as that of any reference point on the NC machine tool Mechanical origin.

在理想情況下，開機加工前不回機械原點，是不會影響機械運行精度的。如果在加工過程中發生斷電、急停、超范圍碰撞等情況，這時重新啟動機床繼續加工將會偏位，你就很難找個剛才的加工位置。雕刻機開機后回機械原點，就是要確定工件坐標相對于機械坐標的位置。這樣在加工過程中發生斷電或緊停的情況，通過重新回機械原點就會找回工件坐標系，這樣就會保證繼續加工的精度。

In an ideal situation, it will not affect the accuracy of the machine if it does not return to the origin before starting the machine. If power failure, emergency stop, out of range collision and other situations occur during the processing, restart the machine tool to continue processing will deviate, and it is difficult for you to find a processing position just now. When the engraving machine starts up and returns to the mechanical origin, it is necessary to determine the position of the workpiece coordinate relative to the mechanical coordinate. In this way, in case of power failure or emergency stop in the process of machining, the workpiece coordinate system will be recovered by returning to the mechanical origin, which will ensure the accuracy of continuous machining.

工件原點就是工件坐標的原點，是為工件尺寸編程確定的原點，一般是工件加工的起始點。工件原點可由編程者選擇。當我們選擇"回工件原點…"選項，刀尖會自動從當前位置回到工件原點。

Workpiece origin is the origin of workpiece coordinate, which is the origin determined by programming for workpiece size, and is generally the starting point of workpiece processing. The workpiece origin can be selected by the programmer. When we choose "return to the workpiece origin The tool tip will automatically return to the workpiece origin from the current position.

為了在回工件原點過程中，刀尖能地通過經過的空間，而不會因為碰到工件、夾具等障礙發生事故，所以，回零路徑進行如下優化： 1，如果終點Z方向坐標大于起點Z方向坐標，則Z軸先單獨進給到Z軸終點位置，然后，X，Y軸聯動，到達目的點。 2， 如果終點Z方向坐標小于起點Z方向坐標，則X，Y軸先聯動到達目的點X，Y坐標，然后，ｚ軸單獨進給到ｚ軸終點坐標。

In order to make the tool tip pass through the space safely in the process of returning to the origin of the workpiece, and avoid accidents due to encountering obstacles such as workpiece and fixture, the zero return path is optimized as follows: 1. If the z-direction coordinate of the end point is greater than the z-direction coordinate of the start point, the z-axis first feeds to the end point of the z-axis, and then the x-axis and y-axis are linked to reach the destination. 2. If the z-direction coordinate of the end point is less than the z-direction coordinate of the start point, the X and Y axes first reach the X and Y coordinates of the destination point, and then the Z axis independently feeds to the z-axis end point coordinate.

因為終點的Z坐標往往在工件的加工表面，為了避免刀尖回到工件零點后碰傷工件表面或刀尖，實際上，Z軸不是回到零，而在零點上方的一個偏置值。該值由"系統參數窗口"的加工參數中的"退刀點"設定

Because the z-coordinate of the end point is always on the machining surface of the workpiece, in order to avoid the tool tip hitting the workpiece surface or tool tip after returning to the zero point of the workpiece, in fact, the z-axis is not back to zero, but an offset value above the zero point. The value is set by the "tool return point" in the processing parameters of the "system parameter window"