1, sending with the move, to cover each piece can be quite different from the generally cover a piece after piece pull, so noise is extremely low.2, this device makes the shield with the move and parallel (to avoid the general shear type shield still has the defects of snakes). In high-speed can more smoothly, no vibration.3, this device can make the shield movement speed up to 120 m/min and higher G value (2 G).4, can increase the service life of the device of the shield.
