Sealing Grommet And Method Of Filling
The grommet used for sealing the charging opening in a pressurized dispensing container is designed so that it can be held in a venting state prior to the charging of the propellant chamber. The design involves an annular ridge above the neck of the grommet and an annular groove above the annular ridge. In that fashion, the grommet can be held loosely on the opening in the base of the container. Flats or cutaways on the crown and groove assure passageway between the propellant chamber and the outside so that air can be taken in and expelled from the propellant chamber during the product loading stages.
The sealing grommet of this invention is an improvement to the sealing grommet design shown in Applicant's U.S. Pat. No. 6,729,362 issued on May 4, 2004 and entitled: Sealing Grommet. The contents of this '362 patent are incorporated herein by reference.
This sealing grommet is adapted to seal the base of a pressurized dispensing container and thus seal the propellant chamber.
The Sealing Grommet described in the '362 patent permits mounting the sealing grommet in a sealed state before the propellant chamber is charged with propellant. By stretching the neck of that grommet with the use of a pin, openings in the base of the grommet are placed in communication with the propellant chamber of the dispensing container. When the propellant chamber is fully pressurized, the stretch pin is removed and the grommet snaps back to its sealed state. This keeps the propellant chamber sealed under pressure so that pressure is deliverable to dispense product through the valve at the top of the container.
During loading of product into the container it is often necessary that the propellant chamber be able to vent air prior to it being pressurized and sealed by the grommet.
It enables faster and more economic filling to have the sealing grommet mounted in the opening at the base of the container during the whole process of product fill so that the grommet does not have to be placed at the base opening after the product filling stage and before the pressurization stage.
Accordingly, it is a purpose of this invention to provide a sealing grommet design for the opening in the base of a pressurized dispensing container in which the grommet will permit venting during the product filling stage and will be immediately accessible to seal the base of the container after the propellant chamber is charged with propellant.
It is a related purpose of this invention to provide the above purpose with a grommet that will be held in the opening at the base of the container without falling out during the product loading steps.
BRIEF DESCRIPTIONThe grommet of this invention seals the small charging opening in the base of the pressurized dispensing container in a fashion described in the '362 patent.
However, in the design of this invention, an annular groove is created in the crown of the grommet above the neck. The groove is spaced from the neck by an annular ridge. The grommet is held in the container base opening before product is loaded into the container. The crown above the grove catches the edge of the container base opening. In this fashion, the grommet is held at the container base opening before the grommet is placed in its sealed state. During this holding stage, product is filled into the product chamber in a fashion that requires venting of the propellant chamber through the container base opening.
Cutaway flats in the annular crown and groove create a passageway between the propellant chamber within the container and the outside during this holding stage. Thus during the product loading stage, when air has to be vented in and out of the propellant chamber, such air can pass through the passageway created by the flats.
After the product has been properly loaded into the product chamber, it is time to charge the compressed air into the propellant chamber. To do so, the grommet is pushed further into the container so that the neck of the grommet engages the edge of the container base opening, thus providing a seal. The propellant is then injected by stretching the neck of the grommet to expose holes through the base of the grommet to the propellant chamber so that pressurized gas propellant can be injected. This propellant injection procedure is described in greater detail in the '362 patent.
More specifically,
The Figures relate to a single embodiment except that
As shown in
During the loading of product into the pressurized container, there is a procedure which is described in greater detail in connection with
First, it is important that the grommet be available to be forced into its sealing state as soon as the charging of propellant into the pressurized chamber is completed.
Second, it is convenient to have the grommet in place during the filling and pressurizing stages as this saves steps in assembly.
The grommet 30 that is an embodiment of this invention, has the crown 12, stretchable neck 16 and base 14 similar to the prior art grommet 10. However, the grommet 30 disclosed herein also has an annular ridge 32 above the neck 16 and an annular groove 34 above the ridge 32. Both the ridge 32 and groove 34 are below the crown 12. The diameter of the crown 12 is greater than the diameter of the container charging opening 18 so that the grommet 30 will be held at the opening 18 and will not fall out during the product filling steps.
During the product loading stages, prior to the charging of propellant into the pressurized chamber, the grommet 30 is loosely held in the opening 18 of the container base 20. A set of four flats 36 are cut across the surface of the crown 12 and groove 34. Thus, in the
After product has been loaded and the pressurized chamber is fully charged, the base 14 of the grommet is forced upward to immediately switch the grommet from the venting state as shown in
The flats 36 are the most convenient way to provide the venting openings between the crown 12 and the opening 18 at the base of the container. They can be slightly scalloped to increase the cross-sectional area of the venting path. But experience has not found that necessary. As shown in
As shown in
As shown in
As shown in
After the product 42 has been appropriately positioned within the container 10, the grommet 30 is forced into its sealing state and then propellant is charged into the propellant chamber by the technique shown in greater detail in the '362 patent. This provides the state shown in
The venting of air is useful to prevent air from going into solution in the product. Where the air does not go into solution, the venting assures that the
The use of this improved valve 30 for venting in connection with a piston 46 operated dispensing container is described herein. However, the venting is also useful when a pouch is used because the filling of the pouch causes the pouch to expand in volume thereby causing air to be vented out through the grommet 30 in its venting state.
The push down step shown in
A presently preferred material for the grommet 10 is a thermoplastic polyester elastomer available from DuPont under the trademark Hytrel as mentioned in column 5 of the '362 prior art patent. It should be noted that the discussion of grommet material set forth in the '362 patent applies to the product of this application.
In one embodiment which is adapted to be used with the container having a 210 mil bottom opening 18, the following significant dimensions are involved. These values are approximate. A mil is one-thousandths of an inch.
While the foregoing description and drawings represent the presently preferred embodiments of the invention, it should be understood that those skilled in the art will be able to make changes and modifications to those embodiments without departing from the teachings of the invention and the scope of the claims.
For example, the flats 36 need not extend to include a portion of the groove 34 if the diameter of the groove 34 is smaller than the flat distance across the crown 12.
Claims
1. In a pressurized dispensing container, a grommet for sealing the opening through which a propellant charge is injected into the container, wherein the grommet has a crown, a base and a resilient stretchable neck between the crown and the base to permit the grommet to be in a sealed state when the neck is in a first extended position and to permit pressurized fluid to be charged into the base of a container through the grommet when the neck is in a second, more extended, position, the improvement comprising:
- an annular ridge above the neck
- an annular groove above said annular ridge and below the crown,
- the crown having a maximum diameter greater than the diameter of the charging opening of the container
- said annular groove dimensioned to fit within the charging opening of the container in a non-sealing state for the grommet, and
- at least one longitudinally extending venting channel along the crown so that when the grommet is in said non-sealing state air can enter and exit from the container through said venting channel during the filling stages of the container,
- said annular groove together with said venting channel positioned within the container in the sealed state of the grommet.
2. The grommet improvement of claim 1 wherein: said venting channel is partially defined by a flat, said flat being on the surfaces of the crown and said groove.
3. The grommet improvement of claim 1 wherein: there are four of said venting channels.
4. The grommet improvement of claim 2 wherein: there are four of said flats creating four of said channels.
5. The grommet improvement of claim 4 wherein: said four flats encompass approximately 50 percent of the circumference of the crown.
6. The method of preparing a pressurized dispensing container containing a piston with product to be dispensed from a product chamber on the top of the piston and with propellant in a propellant chamber under the piston, comprising the steps of:
- holding a grommet in the charging opening at the base of the container in a first position that provides a venting of air in and out of the propellant chamber through a venting channel, said venting channel at least partially defined by the grommet,
- loading product to be dispensed into the product chamber,
- pushing product and piston into a fully downward position to minimize air between product and piston and thus venting gas through the venting channel,
- then applying gas under pressure through the venting channel to force the piston up and thereby minimize air at the top of the product in the product chamber,
- moving the grommet to a second position to provide a seal, and
- charging the propellant chamber with propellant through a charging channel in the grommet to provide pressurized product in the product chamber.
7. The method of claim 6 wherein: said step of pushing occurs simultaneous with said step of loading.
8. The method of claim 6 wherein: said step of pushing occurs after said step of loading.
9. The method of preparing a pressurized dispensing container containing a piston with product to be dispensed from a product chamber on the top of the piston and with propellant in a propellant chamber under the piston, comprising the steps of:
- inserting a grommet into a charging opening in the base of the container to a first position that provides a venting of air in the propellant chamber through a venting channel, said venting channel at least partially defined by the grommet,
- loading product to be dispensed into the product chamber,
- then applying gas under pressure into the product chamber thereby pushing product and piston into a fully downward position to minimize air between product and piston and thus venting gas through the venting channel,
- then applying gas under pressure through the venting channel to push the piston up and thereby minimize air at the top of the product in the product chamber,
- moving the grommet to a second position to provide a seal, and
- charging the propellant chamber with propellant through a charging channel in the grommet to provide pressurized product in the product chamber.
10. The method of preparing a pressurized dispensing container containing a barrier element with product to be dispensed from a product chamber on a first side of the barrier element and with propellant in a propellant chamber on a second side of the barrier, comprising the steps of:
- inserting a grommet into a charging opening in the base of the container to a first position that provides a venting of air in the propellant chamber through a venting channel, said venting channel at least partially defined by the grommet,
- loading product to be dispensed into the product chamber thereby expanding the product chamber, reducing the volume of the propellant chamber and venting air from the propellant chamber, through the venting channel of the grommet as the propellant chamber decreases in volume,
- moving the grommet to a second position to provide a seal, and
- charging the propellant chamber with propellant through a charging channel in the grommet to provide pressurized product in the product chamber.
Type: Application
Filed: Jul 23, 2010
Publication Date: Jan 26, 2012
Inventor: Christian T. Scheindel (Randolph Center, VT)
Application Number: 12/842,331
International Classification: B65B 1/04 (20060101);