| 摘要 |
<p>A liquid valve (10) particularly suited for dispensing of glue at high repetition rate has a solenoid-retracted pin (26) that normally engages a valve seat (34) to close the valve. Glue under pressure enters the chamber (24) in which the pin operates, close to the valve seat (34). To seal against the flow of pressurized glue up along the pin toward the solenoid (44), and also to exert a light valve closing force on the pin, a thin metal bellows (52) member is sealed and fixed to the pin near its lower end (54), at one end of the bellows, and to a connector within which the pin slides, at an opposite, upper end (56) of the bellows. The geometry of the valve seat and the valve closure end of the pin is such that only a very slight retraction of the valve pin opens the valve sufficiently to deliver glue at full velocity through the valve orifice (36).</p> |
