| 摘要 |
The present invention relates to a protection gate valve. Especially, the protection gate valve has the effect of preventing a gate assembly (especially a first O ring and a second O ring) from being corroded or damaged by crack, by including: a gas passage part wherein an inflow hole connected to a vacuum chamber is formed, and an outflow hole connected to the vacuum chamber is formed, and an access hole linked to the inflow hole and the outflow hole is formed; a casing which is linked to the access hole while being connected to the gas passage part; a cylinder comprising a piston rod moving forward and backward in the gas passage part through the access hole; a guide block which is installed between the casing and the cylinder, and surrounds an outer side of the piston rod; a gate assembly which closes the inflow hole and the outflow hole when the piston rod moves forward, while being connected to an end of the piston rod, and opens the inflow hole and the outflow hole when the piston rod moves backward; and a shielding stopper which is installed at a front of the gate assembly, and prevents a gas from flowing into the gate assembly accommodated in the casing, by closing the access hole while the piston rod moves backward. |
