There are many dispensing valves used in automatic dispensing system, such as automatic dispensing machine jet valve, automatic dispensing machine, return suction valve, automatic dispensing machine, double liquid valve, etc.. The working principle of the automatic dispensing machine is through the pneumatic control valve for dispensing dispensing work, produced by air pressure, the pressure will promote the glue in the syringe at the speed of the dispensing needle for dispensing, the automatic dispensing machine front to more automated high quality production, in order to achieve this objective, automatic dispensing machine manufacturers face to the equipment improvement work more professional. Contact dispensing and non-contact dispensing is two working modes of automatic dispensing with the contact dispensing is the most commonly used industry working mode, to perform non-contact dispensing valve assembly is to achieve automatic injection of the injection valve will be the glue treatment for fog and then through the glue outlet to realize spraying, the non-contact dispensing most prominent feature is the glue area wider higher working efficiency and application in some large object production is very extensive, and not drawing the dispensing process, which is characteristic of contact methods are not available.