초록 ▼

An improved plastic seal valve for the bottom of the chamber of a dispensing device in which a valve stem operates. The valve stem is hollow and contains a cross hole which is normally located just above an annular plastic seal made between the housing and the stem at the bottom of the tank, the cro

An improved plastic seal valve for the bottom of the chamber of a dispensing device in which a valve stem operates. The valve stem is hollow and contains a cross hole which is normally located just above an annular plastic seal made between the housing and the stem at the bottom of the tank, the cross hole porting the hollow stem, with the plastic seal allowing closer tolerances in manufacture of the stem and allowing greater accommodation for such distortions as may still occur in molding through flexibility in the bottom stem portion the stem having a taper that just release the sealing pressure and functions on the bottom seal as the upper seal closes. In addition a weaker spring may be used, thus, making it easier to operate the valve while at the same time obtaining improved sealing over the life of the valve.

대표청구항 ▼

In a valve for closing off the bottom of a chamber in a dispensing device including: a. a plastic housing having in its upper portion a cylindrical bore forming a chamber and having an annular sealing wall of smaller diameter below said chamber; b. a cylindrical valve stem comprising: 1. an upper po

In a valve for closing off the bottom of a chamber in a dispensing device including: a. a plastic housing having in its upper portion a cylindrical bore forming a chamber and having an annular sealing wall of smaller diameter below said chamber; b. a cylindrical valve stem comprising: 1. an upper portion containing valve means for use in communication between said chamber and a dispenser outlet; 2. a second cylindrical portion below said upper portion and extending through said chamber; 3. a part of the wall of said second portion in sealing contact with said sealing wall; 4. a hollow recess in the bottom of said second portion extending to above the point of contact between said second portion and said sealing wall when said stem is in an upward, unoperated position; 5. a crosshole through said second portion of said valve stem above said annular sealing wall permitting communication between said hollow recess and said chamber when said stem is in said upward, unoperated position; c. a spring in said chamber closely surrounding said valve stem and urging said valve in an upward direction; and d. means cooperating with said upper chamber to close off said valve means when said stem is in said upward unoperated position, the improvement comprising: e. a flange formed in said metering chamber above the part of said second portion which contacts said annular sealing wall when said stem is depressed, said flange forming a bottom support for said spring, said flange being displaced upward from said sealing wall a distance at least equal to the stem travel during normal operation.