Two-stage air control valve

摘要

The present invention applies to a vacuum transfer system, and relates to an air control valve for controlling the supply of compressed air in a vacuum transfer system. More specially, the air control valve of the present invention is configured to execute a two-stage control. The two-stage control is realized by a piston operation method, in which, although the control is performed by compressed air supplied thereto, a first control unit is operated by an electronic control method, and a second control unit is operated by a pneumatic control method. In particular, the second control unit is operated by vacuum pressure supplied from the vacuum transfer system. The air control valve of this invention can realize improved operational stability, improved energy efficiency and improved operational precision.

主权项

1. A two-stage air control valve, comprising:
a main body including: a cylindrical housing provided with a compressed air passage channel therein such that the passage channel communicates with both an inlet and an outlet that are formed in first and second ends of the housing; a stopper fitted in a middle portion of the passage channel and forming a path at a location between left and right parts of the passage channel; and an electronic control valve mounted to an external surface of the housing; a first control part including: a hollow first piston moving between the inlet and the stopper, thereby opening or closing the path; and a first fluid line extending through the electronic control valve to the inlet of the passage channel, and then branching to either side of an external surface of the first piston; and a second control part including: a hollow second piston moving between the stopper and the outlet, thereby opening or closing the outlet; and a second fluid line extending through a pneumatic control valve at a location to the outlet of the passage channel, and then extending leftward on an external surface of the second piston.