The same mechanism is the most common mechanism of high-speed CNC machine tool guide guard. Its motion principle is similar to that of scissors, so it is also called scissors mechanism. The middle shaft is fixed on each shield. When the machine is moving, it will drive each shield to move. Every shield will not only move at the same time, but also have the same speed and travel. Therefore, it is called the same mechanism. In the structure, with the high speed actuator guideway cover same actuator for single pivot pivoted with the body as a double free agency, its motion system rely on shaft thrust and force transfer, and use the shield track side and the wiper to limit about degrees of freedom, the same motivation consists of single direction movement, therefore when each piece of cover by friction contact with the support and the friction force is not uniform, it will produce torque, the deflection distortion, shield or even stuck phenomenon, at the same time will make the high speed machine tool shield vibration, in fact, because each chip shield produces motion are not the same, so the mechanism of rotating shaft and the connecting rod to withstand these forces, use for a long time can cause the shaft and the connecting rod fracture.

Compared with the low speed telescopic rail guard, the moving speed of the high-speed parallel mechanism guideway shield can reach 100 120m/min, and the acceleration can reach 1g.