Abstract: A dual coil solenoid valve is disclosed for a fuel gas control valve, which comprises a stationary coil assembly and a moving coil assembly, wherein both the stationary coil assembly and the moving coil assembly consist of a magnetic core and a coil. Grooves are provided on the inside of the magnetic cores and coils are arranged in the grooves of the magnetic cores. The stationary coil assembly and the moving coil assembly have an equal cross-sectional area and are arranged oppositely with their axes coinciding with each other. The coils are arranged in the grooves of the magnet cores in such a way that the leakage flux can be reduced and the electromagnetic forces can be increased.

Abstract: A dual coil solenoid valve is disclosed for a fuel gas control valve, which comprises a stationary coil assembly and a moving coil assembly, wherein both the stationary coil assembly and the moving coil assembly consist of a magnetic core and a coil. Grooves are provided on the inside of the magnetic cores and coils are arranged in the grooves of the magnetic cores. The stationary coil assembly and the moving coil assembly have an equal cross-sectional area and are arranged oppositely with their axes coinciding with each other.

Abstract: Disclosed are a grouping method, client, server, and system, which belong to the field of the Internet communications. The method includes: receiving a group initiation request sent by a first client in a current channel, the group initiation request carrying an identifier of the first client; sending group state information to all clients in the current channel; receiving a group joining request sent by a second client in the current channel, the group joining request including an identifier of second client and a position that the second client is to join; sending group state information to all clients again; after every position has a corresponding identifier of a joined client, moving joined clients corresponding to all positions into the same sub-channel to accomplish grouping. This disclosure realizes that as long as the first client initiates a group, the second client can join the group freely to accomplish a grouping operation.