Dispensing – With discharge assistant – With movable nozzle interconnected therewith
Reexamination Certificate
1998-06-17
2001-05-08
Kaufman, Joseph A. (Department: 3754)
Dispensing
With discharge assistant
With movable nozzle interconnected therewith
C222S321400, C222S376000
Reexamination Certificate
active
06227415
ABSTRACT:
TECHNICAL FIELD AND BACKGROUND OF THE INVENTION
The invention relates to a dispenser. Particularly for flowable media which may be gaseous, powdery, pasty and/or liquid. The dispenser is held and operated single-handedly to discharge the medium. The dispenser is intended for use in various positions. For example with the outlet located downwards or upwards. A valve assembly or valve unit is provided. It responds to changes in position of the dispenser by differing valve states.
Such valve units may be an outlet valve, vent valve, mixing valve or the like. The valve unit can control the delivery, pressure or pump chamber. When an inlet valve the volumetrically variable pressure chamber can be filled with medium from a reservoir and through this valve while being expanded or evacuated. The flow direction is then oriented substantially parallel to the pump or valve axis or the like. The valve unit comprises two valves or valve bodies and valve seats following in the flow direction. The upstream valve body is to be translated into its closed position only by gravity. The downstream valve body located nearer to the pressure chamber is translated into its closed position by overpressure in that chamber. An arrangement of valves or valve bodies inverse to the latter is also conceivable.
It may be a disadvantage with such dispensers that the valve responds blocked or delayed when in an end position, for example the closed position. The valve body is thereby pulled into its seat by vacuum or the like so that even higher vacuum at the other side is not instantly sufficient to unseat it. This happens particulary with the first valve which closes as a pop or back valve upon the overpressure in the hauling chamber and should instantly open for filling when this chamber is evacuated. This can also concern the second valve.
OBJECTS OF THE INVENTION
An object is to provide a dispenser which avoids the drawbacks of known configurations or as described. Also a highly reliable valve function should be ensured for a miniaturized dispenser design having components with extremely thin walls.
SUMMARY OF THE INVENTION
In the invention means are provided by which the mass of motion energy of the one valve body is used to lift or push the other valve body out of its stop position, particulary its closed position. The first or second valve seat or valve stop may firstly also be transversely or radially resiliently yieldable. Secondly it may be in contact with the associated valve body when in the stop or closed position. This provides a better centering and more reliable seal. The wall thickness of the first or second valve seat may be less than 1.5 or 0.8 mm and expediently between 0.5 and 0.6 mm. On radial play this wall can easily give way to the contact pressure of the valve body. The seat is able to closely adjust over its full circumference to the shape of the valve elements zone in contact with it. The cited wall thickness is less than the thickness of the wall bounding the hauling chamber at its circumference. The valve wall is contersunk with radial spacing within an outer body.
For the first or second valve body a guide is provided. It is substantially or entirely free of radial motion play over the full valve motion. Thus the valve body can be transferred without transverse motions from one stop position to the other very quickly. The guide is formed by at least three or five circumferentially distributed projections. Longitudinal edge faces thereof extend over the full motion path of the valve body and permanently slidingly engage this body in all of its motions. The medium can flow between the projections through the associated valve chamber from the inlet to the outlet thereof. Flow resistances or flow velocities along the second valve body are thereby less than along the first valve body.
The valve bodies have a specific weight greater than that of the medium. For example by containing a metal, such as steel. For increasing the mass the valve body may consist of metal only in its core. To enhance the cited resilient impact effect on the other valve body the impact face or the outer circumference may also be made of metal. The valve seats or their walls, like all the remaining walls of the dispenser casing or of the piston unit may be made of plastic. The valve bodies could form an assembly unit by being permanently connected to each other directly via a connection. This connector would move commonly with at least one valve body relative to the valve seats. Instead of the valve bodies can be entirely separate balls or the like which are freely movable.
Guide means for the medium flow are provided for protecting at least one valve body against being unseated from its seat by the medium flow counter to its weight force and against coming into contact with the other seat. This specially applies to the second valve body located upstream or farther remote from the hauling chamber. These guide means include a shield covering the valve body over the majority of its base area relative to direct impact of the medium flow directed against it. The guide bypasses this medium flow only into an annular duct about the valve body. The medium flow enters transversely into the valve chamber of this valve body. The flow is directed radially directly against the associated wall and between the projections thereof. Thereby the medium emerges only from a single port. This port covers an arc angle of less than 180° or 90° about the valve axis. The port is bounded integrally over its full circumference, for example by the guide face of the guide means. Also the shield may be integral with the wall of this valve chamber.
A seat or stop for a valve body, as for the first valve body, may be formed by a component separate from all other seats of both valves. This component forms a stop face curved about the valve axis with radial spacing. The component may be a spring, like a helical compression spring. The end winding thereof forms the stop. This spring is a valve closing spring and/or a return spring for the piston unit. Each of the two valve bodies is not spring-loaded toward its closed position or opened position. Instead it is freely movable in each position and controlled only by the conditions of flow, gravity and pressure.
REFERENCES:
patent: 3447551 (1969-06-01), Braun
patent: 4966313 (1990-10-01), Lina
patent: 5346104 (1994-09-01), Jeong
patent: 5615806 (1997-04-01), Grothoff
patent: 3636509 A1 (1987-06-01), None
patent: 3936468 C2 (1996-10-01), None
patent: 0 201 701 A2 (1986-11-01), None
patent: 0286 925 A2 (1988-04-01), None
patent: 2 318 685 (1977-02-01), None
patent: 2 390 213 (1978-12-01), None
patent: 58-170562 (1983-07-01), None
patent: 58-159861 (1983-09-01), None
European Search Report dated Sep. 14, 1999.
Amann Esther
Ritsche Stefan
Ing. Erich Pfeiffer GmbH
Kaufman Joseph A.
Quarles & Brady LLP
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