Patent Application
20120043353
The present invention relates to a valve, in particular to a high flow aerosol valve used in both standard aerosol and bag-on-valve applications, and particularly to a valve having a housing that is supported by a mounting cup for a product container or can, and communicates with a product or product containment bag inside the can, where the radial opening of the valve is positioned closer to a lower seal of the valve stem rather than an upper seal or mounting cup gasket facilitating an increased flow rate for dispensing the product from the container and valve.
Standard aerosol valve and gasket assemblies for dispensing pressurized product from a container have an inherent structural problem which limits the flow rate of product out of the container and through the valve stem. As is well known, the gasket which seals the conventional radial opening of the spring biased valve in the valve housing of conventional aerosol valves also seals the valve stem with the mounting cup of the container limiting the diameter of the opening relative to the valve stem extending through the gasket. The valve stem is provided with both an axial and a radial opening for dispensing product from the container. When the valve stem is pushed down by a user against a spring bias, the radial opening which is initially blocked by the gasket comes into fluid communication with the product in the container which is then permitted to flow through the radial opening and out the valve stem to the environment. Once the user releases the valve stem, the valve stem is biased back into a closed position with the radial opening blocked by the mounting cup gasket.
The structural problem is two-fold, first the radial opening in the side of the valve stem must be smaller than the thickness of the gasket so that the opening is adequately covered in the closed valve position, otherwise there is a substantial risk of the product being able to escape even when the valve is closed by leakage through the radial opening. The general thickness of a conventional gasket is in the range of 1.02 mm-1.52 mm (0.04-0.06 in.), so the radial openings must be substantially within this range. This along with tolerances necessary to ensure complete closure of the valve limits the size of the radial opening. Secondly, the larger the radial opening is on the upper portion of the valve stem where it is located in such conventional valve stems, the more the structural integrity of the valve stem is affected. If the opening is too large the valve stem when subjected to axial and radial forces during depression by a user can fail and break, bend or otherwise permanently damage the valve stem. Such restrictions in the size of the radial opening in the stem make it difficult to obtain high flow rates of product and a highly viscous product such as toothpaste cannot be dispensed without a sufficiently large passage in the valve stem.
Similarly, in other applications such as bag-on-valve assemblies, such valve stem openings create the same or similar structural issues. Collapsible and highly flexible product bags or pouches have become common in different industries for containing a variety of food, beverage, personal care or household care or other similar products. Such product bags can be used alone to allow a user to manually squeeze and dispense a product from the bag or the product bags may be utilized in combination with a pressurized can and product, for example an aerosol. Such product bags and valves contained in and used with aerosol cans are generally referred to in the aerosol dispensing industry as bag-on-valve (BOV) technology. These product bags, valves and cans may be designed to receive and dispense a desired product in either a liquid or semi-liquid form which have a consistency so as to be able to be expelled from the valve or outlet when desired by the user.
Bag-on-valve technology is known to utilize a product dispenser, such as a can, which has the collapsible product bag inserted therein prior to filling of the bag with a product. The bag is initially flat and inserted axially into the can usually in a rolled up manner and having a filling/dispensing valve communicating with the inside of the product bag. The valve is affixed as in the conventional valve described above to a mounting cup portion of the valve and the mounting cup is crimped to the can. During a final manufacturing phase the product bag is filled with the desired product.
In the filling process, a desired product is inserted into the product bag via the two-way valve by appropriate filling means. When the bag is filled by the filling mechanism, the product bag expands inside the can. At some point in the manufacturing process, the can is provided with a pressurized gas in order to assist in squeezing the bag to expel the contents thereof as is well known in the art. Many factors influence the expulsion of the contents or product from the can out of the valve into the environment. The valve is a key component, which has lead to the design of multiple valve configurations for different applications.
Typically, bag-on-valve applications have used valves that have two components—a valve housing and a valve stem. In most applications, the valve housing engages with a mounting cup of a can, attaches to a bag that holds the product, and provides the framework for the valve stem. The valve stem usually interacts with the valve housing through the use of a spring. The spring allows the valve stem to move relative to the valve housing to open and close the valve. Typically, when the valve is opened, product flows from the product bag, to and through the valve housing, then through a passage in the valve stem, and finally into the environment. The passage is normally limited in size and shape based on the sealing of the passage by the upper gasket that is used to seal the valve housing to the mounting cup.
An issue associated with the bag-on-valve technology is control of the volume flow of the product contents of the bag from the system to the environment. This issue is especially compounded due to the different viscosities of the various products which manufacturers dispense from such bag-on-valve containers. The various product contents include liquids, creams, foams, gels, aerosols, colloids, and various other substances. Handling the flow of a highly viscous substance such as for instance, toothpaste is particularly difficult in both conventional and bag-on-valve applications where the aerosol dispensing radial passages are particularly small in the 1.02 mm-1.52 mm (0.04-0.06 in.) range and there is no structural feasibility to make these holes larger with conventional valve structures. The problem is to be able to accommodate larger dispensing openings in the valve beyond the 1.02 mm-1.52 mm (0.04-0.06 in.) range in order to accommodate higher flow rates and more viscous product.
The present invention is directed to a valve used in both conventional and bag-on-valve aerosol container applications that allows a high flow rate of especially viscous substances. In a first embodiment of the present invention the valve includes a valve housing, a valve stem, and a spring or other biasing device that allows the valve stem to move relative to the valve housing. The valve stem is substantially hollow to allow the flow of product to and from a bag attached to the valve housing. There is a radial bore or bores and a seal near the bottom of the valve stem that dictate the passage and flow rate of pressurized product between the product container and the environment. The radial bore at the bottom or lower portion of the valve stem provides for flow directly from the product reservoir to the valve stem passage when a lower seal on the valve is opened. The valve stem passage is sealed by the lower seal or ring which is a separate sealing gasket or ring from the upper gasket. The lower seal may be located anywhere along the valve stem below the upper gasket and preferably at the bottom or lower portion of the valve stem facilitating communication to the product reservoir.
As a reference point the upper portion of the valve stem and upper gasket refers to the end of the valve stem and the gasket adjacent the orifice in the mounting cup. The lower portion of the valve stem and the lower gasket or ring are located axially spaced below the upper portion and generally more interior of the container so that product ejected from the container when the valve is actuated travels from the lower portion of the valve stem past the lower gasket or ring up through the upper portion of the valve stem and out of the valve.
The addition of a lower sealing gasket or ring allows one or more larger diameter bore(s) to be radially formed in the lower portion of the valve stem without compromising the integrity of the valve stem itself. The bore shape and larger size can be selected to facilitate a high volume flow rate for highly viscous substances. For example a triangular or polygonal shape could provide a variable flow rate into and through the valve stem to ensure that highly viscous materials are dispensed at a desired flow rate depending on a user's actuation pressure. It is, therefore, an object of the present invention to overcome the above noted issues and produce a valve for both conventional aerosol valve and bag-on-valve systems which facilitates a high volume flow rate for liquids and semi-liquids of different viscosities.
It is another object of the present invention to easily facilitate varying flow rates based on the point of depression of the valve.
It is a still further object of the present invention to provide a high volume flow rate for highly viscous substances that typically have difficulty being dispensed.
It is yet another object of the present invention to simplify the process of adding and discharging the contents of the aerosol can, container or product bag by allowing the product to go directly from the valve stem into the container or product bag without having to pass through the valve housing.
Another object of the present invention is to provide a two-way valve which permits a substantial increase in the speed of filling a product container or bag, especially in the context of highly viscous substances.
The present invention relates to a valve for use in a pressurized aerosol application, the valve comprising a valve housing having an outer surface for supportive engagement with a mounting cup for a product container and a first cavity defined within the valve housing for receiving valve components comprising, a valve stem springingly engaged with the valve housing, the valve stem defining a central passage for dispensing pressurized product to the environment and a lower end portion including a sealing ring for engaging a sealing edge of the valve housing, and at least one radial bore formed in a sidewall of the valve stem located in the lower end portion of the valve stem, the at least one radial bore leading to the central passage extending from the radial bore to a dispensing orifice at an upper end portion of the valve stem.
The present invention also relates to an actuator for an aerosol container comprising a valve housing defining a cavity for receiving valve components comprising an upper portion for engaging a mounting cup for an aerosol container, a chamber for containing a spring, and a lower sealing edge defining an opening into the valve housing; an inner seal between the upper portion of the valve housing and the mounting cup; a valve stem supported within the valve housing and axially moveable relative thereto in accordance with the spring, the valve stem comprising; a passage extending between a radial opening at a lower end of the valve stem and an axial opening at an upper end of the valve stem; and receiving a lower seal supported on the valve stem between the radial opening and a lowermost end of the valve stem.
The present invention also relates to a method of making an actuator for dispensing product from an aerosol container through the actuator comprising the steps of providing a valve housing defining a cavity for receiving valve components comprising the steps of engaging an upper portion of the valve housing in a mounting cup of the aerosol container, forming a chamber for containing a spring, and placing a lower sealing edge defining an opening into the valve housing; providing an inner seal between the upper portion of the valve housing and the mounting cup; supporting a valve stem within the valve housing and axially moveable relative thereto in accordance with the spring, the valve stem comprising the steps of; extending a passage between a radial opening at a lower end of the valve stem and an axial opening at an upper end of the valve stem; and placing a lower seal on the valve stem between the radial opening and a lowermost end of the valve stem.
These and other features, advantages and improvements according to this invention will be better understood by reference to the following detailed description and accompanying drawings.
The bottom portion 11 is better illustrated in the perspective view of
Turning to
As shown in
The valve stem 7 defines a product passage 19 that extends substantially the entire length of the valve stem 7. The passage 19 starts from a radial bore(s) 21 adjacent a lower end of the valve stem 19. As described in detail below, the location of the bore(s) 21 near the lower end of the valve stem 7 permits a larger bore opening that consequently allows for greater flow of product contents from the product bag relative to conventional valves into the product passage 19 and out of the valve stem 7.
By compressing the valve stem 7 along the axis A the valve is opened as shown in
The valve stem 7 is engaged within the valve housing 3 and biased into the closed state by the use of spring 33 or another biasing device forcing the stem 7 axially upward and into the closed position with the sealing ring 31 closing the valve against the sealing edge 24. It is to be appreciated that although there is no radial opening or bore in the region of the inner gasket 29, the inner gasket 29 provides a seal between the valve housing 3, the sliding valve stem 7 and the mounting cup 5. The spring 33 keeps the valve stem 7 closed so that the product in the product bag cannot communicate with the environment through the valve 1. The spring 33 has an upper end which typically axially engages the valve stem 7 at a lip or stop 27 that extends partially or completely around an outer wall of the valve stem 7. The lower end of the spring 33 is supported by the valve housing 3 at a circumferential edge 28 around the interior wall of the spring cavity 9. The spring 33 bias provided by the spring 33 allows for the depression and movement of the valve stem 7 relative to the valve housing 3 enabling the valve 1 to be varied between an open state as shown in
In the open state shown in
Another important aspect of the present invention is the shape of the bores 35 which can facilitate control over dispensing of product at a high flow rate through the valve.
The radial bores or passages can be formed in a desired shape or size to facilitate product flow. In another embodiment of the present invention, the bores are designed to have a profile and area so that depending on how far down the valve stem 7 is pressed relative to the sealing edge 24, a desired variable flow rate can be achieved which depends on how exposed the bore 35 is. Different shapes and sizes may be used for different products and end results. For example,
Since certain changes may be made in the above described improved continuous dispensing actuator assembly, without departing from the spirit and scope of the invention herein involved, it is intended that all of the subject matter of the above description or shown in the accompanying drawings shall be interpreted merely as examples illustrating the inventive concept herein and shall not be construed as limiting the invention.
