Claims
- 1. For use in a tilt action valve assembly in which a valve body has a valve seat and a hollow stem with port means communicating between the interior of the stem and the top of the valve seat for passage therethrough of a viscous product under pressure; said valve body being secured to a mounting means by a sealing grommet which surrounds at least a lower portion of the valve stem, including the port means, and abuts the top of the valve seat; tilting of the valve stem relative to the mounting means causing the valve seat to move away from a lower portion of the sealing grommet and opening access to the port means for product located below the valve seat; the improvement which comprises means for inhibiting the seepage of the product between the valve stem and the sealing grommet, said inhibiting means comprising a pocket formed in the lower portion of the grommet, said pocket configured and positioned for receiving some of the viscous product as it flows toward the port means and retaining such product even after valve stem tilting is terminated; said pocket having a side wall lying along a significant length of the lower portion of the valve stem, so as to abut the top of the valve seat, such that pocket retained product exerts a significant force against said side wall to urge it against the lower portion of the valve stem to thereby inhibit product seepage therebetween.
- 2. For use in a tilt action valve assembly in which a valve body has a valve seat and a hollow stem with port means communicating between the interior of the stem and the top of the valve seat for passage therethrough of a viscous product under pressure; said valve body being secured to a mounting means by a sealing grommet which surrounds at least a lower portion of the valve stem, including the port means, and abuts the top of the valve seat; tilting of the valve stem relative to the mounting means causing the valve seat to move away from a lower portion of the sealing grommet and opening access to the port means for product located below the valve seat; the improvement which comprises means for inhibiting the seepage of the product between the valve stem and the sealing grommet, said inhibiting means comprising a pocket formed in the lower portion of the grommet, said pocket configured and positioned for receiving some of the viscous product as it flows toward the port means and retaining such product even after valve stem tilting is terminated; said pocket having a side wall lying along a significant length of the lower portion of the valve stem, such that pocket retained product exerts a significant force against said side wall to urge it against the lower portion of the valve stem to thereby inhibit product seepage therebetween; and the length of said side wall, in combination with the position of the port means, causes said side wall to cover the port means when the valve stem is not being tilted.
- 3. For use in a tilt action valve assembly in which a valve body has a valve seat and a hollow stem with port means communicating between the interior of the stem and the top of the valve seat for passage therethrough of a viscous product under pressure; said valve body being secured to a mounting means by a sealing grommet which surrounds at least a lower portion of the valve stem, including the port means, and abuts the top of the valve seat; tilting of the valve stem relative to the mounting means causing the valve seat to move away from a lower portion of the sealing grommet and opening access to the port means for product located below the valve seat; the improvement which comprises means for inhibiting the seepage of the product between the valve stem and the sealing grommet, said inhibiting means comprising a pocket formed in the lower portion of the grommet, said pocket configured and positioned for receiving some of the viscous product as it flows toward the port means and retaining such product even after valve stem tilting is terminated; said pocket having a side wall lying along a significant length of the lower portion of the valve stem, such that pocket retained product exerts a significant force against said side wall to urge it against the lower portion of the valve stem to thereby inhibit product seepage therebetween; and said pocket has another side wall the end of which abuts the valve seat at an elevation different than the end of said side wall, and the valve seat has an interior portion which extends into abutting position with the end of said side wall.
BACKGROUND OF THE INVENTION
This application is a continuation of application Ser. No. 580,118, filed Feb. 14, 1984, now abandoned, which is a continuation of application Ser. No. 284,478, filed July 17, 1981, now abandoned.
This invention relates generally to tilt action valve assemblies for dispensing materials from pressurized containers. More specifically, this invention embodies a grommet specially designed to coact with the valve stem, valve seat and material to be dispensed to more tightly seal the periphery of the valve stem against leakage of the container contents, to operate more controllably with less tilt action pressure, and be easier and cheaper to assemble.
Tilt action valves, mounted on pressurized cans, for dispensing shaving cream, whipping cream, etc. are well known. A few examples are disclosed in U.S. Pat. Nos. 2,704,172; 2,852,168; and 2,877,936. Such valve assemblies are for dispensing materials which are mixed with gases under pressure. A common problem of prior art tilt valve assemblies is that the propellant gas itself and also the pressurized material leak out through the valve parts. The above cited patents teach construction which combat the leakage problem. Another prior art problem is that the valve stem and grommet are too resilient to be readily controllable by the tilting pressure applied by the forefinger of the typical user. If the valve assembly is not so resilient, then there typically results leakage around the valve stem. Efforts to resolve both of the above problems led to consideration of overly complex and expensive tilt valve assemblies, which were not practical from both manufacturing and sales aspects.
More recently, there has been commercialized a dispensing container in which the product to be dispensed and the gas propellant are kept separate at all times, and not mixed. The container includes a piston-like member which separates the gas from the product. In this manner, the product is not aerosolized or "whipped" and can be delivered as a viscous material, such as a spread cheese. Pressures of one hundred pounds per square inch are common for this type of dispenser. The use of prior art tilt action valves for such viscous material proved to renew the old problem of leakage between the valve stem and grommet. Designs to improve the sealing or gasketing action by the grommet against the valve stem, and also coactive designs of the stem, as by ribs, etc. to hold mating portions of the grommet, have provided some improvement, but resulted in a trade-off with other features and resulted in increased undesirable resiliency, design complexity, and production cost. Reference may be made to the following patents for examples of some of those designs: U.S. Pat. Nos. 2,889,086; 3,048,307; and 3,101,875.
The prior art has faced yet another problem, due to the need of specially configured valve stems and grommets. Such problem is parts assembly. The assembling of the valve stem, grommet and other portions of the tilt valve onto the mounting cup, for securing onto the top of the container, is not simple, as is evident from the herein cited references. The need to seat parts into precise mating relationship has prevented the simple assembling technique of sliding one part into the next.
The present invention seeks to provide a tilt action valve assembly, especially capable of dispensing viscous materials, without leakage between the valve stem and surrounding grommet. Between the inner, hollow, annular surface of the grommet, which fits tightly against the periphery of a relatively large longitudinal portion of the valve stem, and the lower, depending skirt portion of the grommet, which seals against the valve head when the valve is closed, there is formed in the grommet a relatively large, inverted pocket. This pocket is open to receive and retain a portion of the viscous product, when the valve stem is tilted, and thereafter to retain some of the viscous product after the valve stem returns to its normal position. One side wall of the inverted pocket extends along a significant length of the valve stem, commencing at or just above the valve head, such that the pocket-retained viscous material exerts force radially inward against the side wall to seal same tightly against the valve stem. The pocket also provides for more flexibility and tilt control than if the grommet were entirely solid between the valve stem and skirt. Various embodiments of the pocket formation and valve head are disclosed. All embodiments are economic to fabricate and easy to assemble. The simplicity of grommet and valve designs permits the grommet to be slipped into the mounting cup and then the valve stem is slipped up into the grommet.
US Referenced Citations (5)
Continuations (2)
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Number |
Date |
Country |
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580118 |
Feb 1984 |
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| Parent |
284478 |
Jul 1981 |
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Patent Grant
4824075
