US3709410A

US3709410A - Aerosol valve with differential flow control rate

Info

Publication number: US3709410A
Application number: US00059464A
Authority: US
Inventors: E Cunningham
Original assignee: Pittway Corp; BARR STALFORT CO
Current assignee: AptarGroup Inc; BARR STALFORT CO
Priority date: 1970-07-30
Filing date: 1970-07-30
Publication date: 1973-01-09
Anticipated expiration: 1990-01-09

Abstract

This invention relates generally to a new and improved valve associated with aerosol type containers, for example, and more particularly to a valve which permits more rapid filling of a small-orificed valve through the use of a uni-directional, pressure-actuated, expanding slot valve body.

Description

United States Patent 91 [111 3,709,410

Cunningham [451 Jan. 9, 1973 [54] AEROSOL VALVE WITH [56} References Cited QLFTFgRENTIAL FLOW CONTROL UNITED STATES PATENTS 3,060,965 10/1962 Taggart ..222/402.l6 x [75] Invent u Llbertyv'ne 3,150,832 9/1964 Soth .239/534 x [73] Assignee: Barr-Stalfort Company, Division primary Examineppoben Reeves Pittway Corpoi ation, Niles, Ill. Assistant Examiner-John P. Shannon, Jr. [22] Filed; Jul 30, 1970 Attorney-Merriam, Marshall, Shapiro & Klose [21] Appl. No.: 59,464

[57] ABSTRACT [52] US'CL 222/402 16 141/20 This invention relates generally to a new and im- 51 in. ct. .'.'.'..'.'.'.'fff".'.'.'.'.'.'f.'""IIIIII' 13650 83/14 valve mated with [58] Field of searchnmlll 20; 138/45; ZZZ/40216 for example, and more particularly to a valve which 222M06407;251/120;239/534 permits more rapid filling of a smallorificed valve through the use of a uni-directional, pressure-actuated, expanding slot valve body. I

7 Claims, 7 Drawing Figures r & [5 Y fl/a 75 In I N :T

22 h I 22 2/ I p ,9 i M AEROSOL VALVE WITH DIFFERENTIAL FLOW CONTROL RATE BACKGROUND OF THE INVENTION The utilization of a pressurized package as a vehicle for dispensing liquid substances such as hair sprays, cleaners, waxes and disinfectants has become highly acceptable and desirable in the market place. More and more products are now being packaged in aerosol containers. The type of products which are so packaged vary significantly in their properties, and the containers in which the products are packaged differ appreciably in size and shape. These variations in product properties and containers present problems to those involved in filling packages.

In the filling industry, wherein liquid products are pressure packaged with a gaseous propellant in aerosol containers, several different methods are presently employed for filling the assorted containers and packaging the different types of products. One method involves what is termed the cold fill method of filling. The liquid product and gaseous propellant are both refrigerated prior to their introduction into an open container. This refrigeration cools the propellant to a liquid state and delays liquid to vapor transition of the propellant for a period sufficient to permit insertion of a valve assembly in the container and to effect closure of the can and valve assembly. For some products, the cold fill method is not satisfactory due to the product formulation. For example, water base products have a tendency to freeze in the refrigeration step of the filling operation. Additionally, it has been found that some propellant is wasted in this type of filling operation in that the propellant will vaporize and escape from the container before closure of the valve assembly and container is completed.

A second method employed for filling aerosol type containers is commonly referred to as the under cap" method. In this operation, the product is initially in troduced into the container by a conventional liquidproduct filling machine and a valve is loosely inserted into the can. A vacuum is then drawn on the container after which a liquid propellant is injected therein at high pressure (e.g., approximately 750 psig.). Subsequently, the valve cup of the assembly is crimped to the container by means of an internally expanding collet. However, in the time between the injection of the propellant into the container and the subsequent crimping operation, a portion of the liquid propellant is trapped between the container closure and the filling machine, and this propellant is lost in the filling operation. While the loss of propellant for a single can may be minimal, this loss becomes quite significant in production line operations where hundreds of con tainers are being filled by the under cap" method. Attempts to reduce the loss of propellant associated with this particular filling method have not been entirely satisfactory; and, accordingly, other filling methods are employed.

A third method employed for filling aerosol containers involve pressure filling a container. In this operation the product is put into a container at room temperature, after which a valve assembly is inserted, a vacuum is drawn and the valve crimped. A propellant injector machine is then mated with the valve cup and propellant is released at high pressure and forced into the container through the valve assembly. While an advantage of the pressure-fill operation is minimum loss of propellant, as compared to the previously described methods of filling, a disadvantage heretofore inherent with this system resides in the inordinate amount of time required to complete the fill of valves with restrictive orifices as compared to the time associated with the cold fill" and under cap method of filling.

The rate of fill per container is quite important, par ticularly where production line filling operations are involved. One factor which influences the rate of fill is the size of the orifice in the valve body, which orifice meters the flow of product through the valve assembly and controls the spray characteristics of the product dispensed from the container. The diameter of the orifice in the valve body is often quite small, ranging from approximately 0.013 inches to 0.080 inches.

The trend has been to reduce the size of this orifice because a smaller orifice provides better control of the spray characteristics and extends the useful life of the aerosol product. A significant disadvantage of reduction in orifice size is that the filling rate of a container is decreased. For example, with a valve body having an orifice size of about 0.062 inch diameter, filling rates in the range of 50-75 grams per second can be achieved with a pressure of 800 psig. However, when the orifice diameter is reduced to a diameter of 0.0l3 inch, the filling rate drops to less than 10 grams per second.

SUMMARY OF THE INVENTION It would be desirable to provide high filling rates with small orifice sizes while employing the pressure fill method. The invention disclosed and claimed herein relates to a valve assembly having a valve body which provides the advantages associated with small orifices and additionally assures high filling rates where the pressure fill method is employed.

Briefly, the instant invention relates to a valve body construction which permits differential directional flow rates without adjustments or compromise of standard valve characteristics. The flow rate into a container during the course ofa pressure fill operation is substantially increased as compared with flow rates presently available; whereas the reverse flow, or flow out of the aerosol container, upon actuation of the valve by a user, is precisely metered by the restrictive valve body orifice.

The desirable features of the valve body are achieved by slitting the valve body. The slit can be held in a nor mally closed position by a dip tube covering the lower end of the valve body, or in those instances where no dip tube is employed in the assembly, or the tube is covered by the valve body, the valve body can be made of a material having sufficient resiliency to return the slit portions ofthe body to their normal position follow' ing a filling operation.

Other features and advantages are inherent in the subject matter disclosed and claimed herein, as will become apparent to those skilled in the art from the following detailed description, including the accompanying illustrative drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view of an aerosol container with a dip tube and actuator means;

FIG. 2 is an enlarged fragmentary sectional view of the container of FIG. 1 including a valve assembly having an embodiment of the valve body of the present invention in a normally closed position;

FIG. 3 is an enlarged fragmentary sectional view of the valve assembly of FIG. 2 with the valve body in an open position during a pressure fill operation;

FIG. 4 is a bottom end view of the valve body of FIG.

FIG. 5 is a side view of the valve body of FIG. 2;

FIG. 6 is a bottom view of an embodiment of the present invention showing a valve body having a plurality of slits spaced from the longitudinal axis; and,

FIG. 7 is a bottom view of another embodiment of the present invention in which a valve body is slit in a plurality of locations along the radial axis.

Referring to the drawings and more particularly to FIGS. 1 and 2, there is shown an aerosol container 10 having a valve assembly 11 and an actuator button 9 attached to the top of valve assembly 11. One end of a dip tube 12 depends from the valve assembly while the remaining end of the tube extends close to the bottom ofthe container.

Container 10 has an open top to accommodate valve assembly 11 having an annular mounting cup 14 crimped into a peripheral container top curl 13 by means of a collet which, when expanded, causes the outer side wall of valve cup 14 to expand so that its diameter exceeds the diameter of curl l3. Gasket material disposed on valve cup 14 is compressed between cup 14 and curl l3 and assists in forming a leak-free seal between valve cup 14 and container curl 13.

Valve assembly 11 also comprises valve stem 15, valve seat 16 and spring 17. Part of stem and spring 17 are located in a valve body and seat 16 provices a seal between annular cup 14 and valve body 20. Stem 15 has an upper tubular portion 18 which extends upwardly through mounting cup 14 and a lower stem portion 19 biased to a normally closed position against the bottom surface of seat 16 by spring 17. Referring to FIG. 3, upon actuation of the valve by depression of actuator button 9, stem 15 is pushed down whereby an opening is provided between upper surface 21 oflower stem portion 19 and the bottom surface 22 of seat 16 for the outward passage of pressurized fluid from container l0 sequentially through dip tube 12, valve body 20 and a plurality oflateral channels 23in stem 15.

Valve body 20 may be made of a plastic material such as nylon, teflon, polystyrene, ABS, acrylic, phenolic or vinyl resin. Valve body 20 comprises a cup portion 25, in which stem 15 and spring 17 are located, and a depending tubular section 26, to which one end ofdip tube 12 is attached. While one type of valve body 20 has been illustrated in the drawings, the size and shape of such bodies differ in that numerous valve assemblies are commercially available and it is not intended to limit the structure of the valve body to that disclosed in the drawings.

Dip tube 12 is composed of elastic material and the top thereof encloses and is frictionally retained on tubular section 26 by ribs 28 projecting outwardly from tubular section 26. Ribs 28 assist in the retention of dip tube 12 on tubular section 26 by providing several pressure points acting outwardly against the inner wall 30 oftube 12.

As shown in FIG. 2, the diameter of the interior of valve body tubular section 26 becomes successively smaller in a downward direction, with the metering orifice 31 having a diameter in the range of about 0.0 l 3 to 0.080 inch.

The valve body, as seen more clearly in FIGS. 2 and 3, is slit at 27 along the lower portion of tubular shaped section 26, the slit extending the depth of orifice 31.

Valve body 20 normally is in a closed position with slit 27 closed so that fluid flow through the valve body will be confined to orifice 31 only. However, in response to high pressure reverse flow (i.e., pressures in the magnitude of 600-l200 psig.) slit 27 will be forcibly expanded or opened in the filling position of FIG. 3. With valve body 20 thus forced open, relatively unrestricted inward flow can occur through the valve assembly whereby the filling time is substantially reduced compared to filling times presently available using pressure fill on restricted orifice valves. After the filling operation is completed and the filling pressure is released, slit 27 contracts and valve body 20 returns to the normal closed position shown in FIG. 2. Valve body 20 is urged to its closed position by the engagement of the upper portion of dip tube 12 around valve body tubular section 26. This engagement exerts a compressive force on valve body 20 and normally keeps it from spreading apart.

While aerosol containers are designed to withstand internal pressures up to 200 psig., the design of the slit valve body of the present invention is such that only pressures exceeding about 600 psig. will be able to force or spread open body 20. Accordingly, valve body 20, slit in the manner shown, for example in FIG. 2, serves as a uni-directional valve which opens only during the course ofa pressure fill operation.

The slit in body 20 extends through the lower portion of section 26. The slit can be put into the body when it is molded or can be machined following a molding operation. While the length of the slit can vary, preferably the slit will traverse most of the length of tubular section26. The criterion for the slit length is that upon pressure filling, the slit permits by-pass of or enlargement of orifice 31 in tubular section 26 to provide the desired flow rate of propellant or other material into container 10.

Instead of slitting the valve body as described herein, the valve body could be designed to provide a very small slot, a-approximately 0.005 inch wide. A slotted valve body could be held with the slotted sections closed together by the compressive force exerted by dip tube 12. The slot would be small enough and of sufficient length that, except for the filling operation, the slot would not adversely affect the operation of the valve body upon actuation of button 9 by a user.

While one slit has been described herein, it is appreciated that more than one slit can be utilized for expanding the size of orifice 31; For example, as shown in FIG. 6, two slits 40 which are parallel to each other and to the longitudinal axis of the container, could be utilized. Alternatively, one or more slits 50 could be made in the valve body at an angle to the longitudinal axis of the container such as illustrated in FIG. 7 wherein the slits 50 are located along the radial axis of valve body 20.

While valve body 20 has been illustrated with section 26 enclosed by tube 12, there are some valve bodies employed wherein the dip tube is inserted into tubular section 26 with the upper end of the dip tube enclosed by section 26. In valve bodies of this type, the small orifice is sometimes located at the bottom of valve body cup portion 25 as opposed to being positioned in tubular section 26 as seen in the drawings. The slitting of this type of valve body will provide the desired increased filling rate so long as the slit is of such a length to permit the small orifice in cup portion 25 to expand during a pressure fill operation. As the slit sections of valve body 20 are forced outward in the course of a pressure fill operation, dip tube 12, through which the incoming propellant flows, also expands outward but is retained within section 26. The dip tube is elastic enough to expand and retract without need of slitting the dip tube. In this embodiment, retaining ribs are disposed on the inner wall of section 26 to assist in retention ofdip tube 12.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom as modifications will be obvious to those skilled in the art.

What is claimed is:

l. A valve body for use in a valve assembly with an aerosol type container which is adapted to be subjected to a pressure fill operation wherein fluid is directed into an aerosol type container and the valve body is joined to a resilient dip tube having inner and outer walls and said valve body is adapted to receive a valve stem and biasing means for actuating the valve assembly, said valve body being further adapted to be expandable in the course of a pressure fill operation to allow expansion of said valve body during a pressure fill operation; said valve body comprising:

a cup portion;

a resilient tubular shaped section depending from said cup portion;

said section having an outer wall;

said dip tube being connected in a substantially leak free connection to said section with a portion of said inner wall of said dip tube being positioned over said outer wall surface of said section;

said section having at least one metering orifice for regulating the flow of fluid through said assembly and into said dip tube;

said section having expansion means, responsive to pressure, for allowing the expansion of the size of said section to provide an increased fluid entry means during a pressure fill operation;

said expansion means comprises at least one slit in said body which is free of intersecting said orifice; and,

said section and said resilient dip tube portion being adapted to expand together when, during a pressure fill operation, fluid flows through said section and resilient dip tube, and adapted to contract together to their normal position subsequent to a pressure fill operation.

2. A valve body in accordance with claim 1 wherein said expansion means comprises at least one slit in said body which extends at least the depth of said orifice.

3. A valve body in accordance with claim 1 wherein said expansion means comprises a plurality of slits in said section.

4. A valve body for use in a valve assembly with an aerosol type container which is adapted to be subjected to a pressure fill operation wherein fluid is directed into an aerosol type container and the valve body is jointed to a resilient dip tube having inner and outer walls and said valve body is adapted to receive a valve stem and biasing means for actuating the valve assembly, said valve body being further adapted to be expandable in the course of a pressure fill operation to allow expansion of said valve body during a pressure fill operation; said valve body comprising:

a cup portion;

a resilient tubular shaped section depending from said cup portion;

said section having an outer wall;

said section having at least one metering orifice for regulating the flow of fluid through said assembly and into said dip tube; said section having expansion means which are free of intersecting said orifice and which are responsive to pressure for allowing the expansion of the size of said section to provide an increased fluid entry means in said section; and,

said section and said resilient dip tube portion being expandable when said section is enlarged whereby, during a pressure fill operation, fluid flows through said expansion means and orifice in said. section and said resilient dip tube.

5. An aerosol type container having a valve body in a valve assembly which body is adapted to be subjected to a pressure fill operation wherein fluid is directed into said aerosol type container and the valve body is joined to a resilient dip tube having inner and outer walls and said valve body is adapted to receive a valve stem and biasing means for actuating the valve assembly, said valve body being further adapted to be expandable in the course of a pressure fill operation to allow expansion of said valve body during a pressure fill operation; said valve body comprising:

a cup portion joined to said container;

a resilient tubular shaped section depending from said cup portion;

said section having an outer wall;

said dip tube being connected in a substantially leak free connection to said section with a portion of said inner wall of said dip tube: being positioned over said outer wall surface of said section;

said section having at least one metering orifice for regulating the flow of fluid through said assembly and into said dip tube; said section having expansion means which are free of intersecting said orifice and responsive to pressure, for allowing the expansion of the size of said section to provide an increased :fluid entry means in said section during a pressure fill operation; and,

said section and said resilient dip tube portion being expandable when said section is enlarged whereby, during a pressure fill operation, fluid flows through said means and orifice in said section and said resilient dip tube.

6. An aerosol type container in accordance with claim in which said section expansion means comprises at least one slit in said body.

7. An aerosol type container in accordance with claim 5 in which said section expansion means com- 5 prises a plurality of slits in said body.

Claims

1. A valve body for use in a valve assembly with an aerosol type container which is adapted to be subjected to a pressure fill operation wherein fluid is directed into an aerosol type container and the valve body is joined to a resilient dip tube having inner and outer walls and said valve body is adapted to receive a valve stem and biasing means for actuating the valve assembly, said valve body being further adapted to be expandable in the course of a pressure fill Operation to allow expansion of said valve body during a pressure fill operation; said valve body comprising: a cup portion; a resilient tubular shaped section depending from said cup portion; said section having an outer wall; said dip tube being connected in a substantially leak free connection to said section with a portion of said inner wall of said dip tube being positioned over said outer wall surface of said section; said section having at least one metering orifice for regulating the flow of fluid through said assembly and into said dip tube; said section having expansion means, responsive to pressure, for allowing the expansion of the size of said section to provide an increased fluid entry means during a pressure fill operation; said expansion means comprises at least one slit in said body which is free of intersecting said orifice; and, said section and said resilient dip tube portion being adapted to expand together when, during a pressure fill operation, fluid flows through said section and resilient dip tube, and adapted to contract together to their normal position subsequent to a pressure fill operation.

4. A valve body for use in a valve assembly with an aerosol type container which is adapted to be subjected to a pressure fill operation wherein fluid is directed into an aerosol type container and the valve body is jointed to a resilient dip tube having inner and outer walls and said valve body is adapted to receive a valve stem and biasing means for actuating the valve assembly, said valve body being further adapted to be expandable in the course of a pressure fill operation to allow expansion of said valve body during a pressure fill operation; said valve body comprising: a cup portion; a resilient tubular shaped section depending from said cup portion; said section having an outer wall; said dip tube being connected in a substantially leak free connection to said section with a portion of said inner wall of said dip tube being positioned over said outer wall surface of said section; said section having at least one metering orifice for regulating the flow of fluid through said assembly and into said dip tube; said section having expansion means which are free of intersecting said orifice and which are responsive to pressure for allowing the expansion of the size of said section to provide an increased fluid entry means in said section; and, said section and said resilient dip tube portion being expandable when said section is enlarged whereby, during a pressure fill operation, fluid flows through said expansion means and orifice in said section and said resilient dip tube.

5. An aerosol type container having a valve body in a valve assembly which body is adapted to be subjected to a pressure fill operation wherein fluid is directed into said aerosol type container and the valve body is joined to a resilient dip tube having inner and outer walls and said valve body is adapted to receive a valve stem and biasing means for actuating the valve assembly, said valve body being further adapted to be expandable in the course of a pressure fill operation to allow expansion of said valve body during a pressure fill operation; said valve body comprising: a cup portion joined to said container; a resilient tubular shaped section depending from said cup portion; said section having an outer wall; said dip tube being connected in a substantially leak free connection to said section with a portion of said inner wall of said dip tube being positioned over said outer wall surface of said section; said section having at least one metering orifice for regulating the flow of fluid througH said assembly and into said dip tube; said section having expansion means which are free of intersecting said orifice and responsive to pressure, for allowing the expansion of the size of said section to provide an increased fluid entry means in said section during a pressure fill operation; and, said section and said resilient dip tube portion being expandable when said section is enlarged whereby, during a pressure fill operation, fluid flows through said means and orifice in said section and said resilient dip tube.

6. An aerosol type container in accordance with claim 5 in which said section expansion means comprises at least one slit in said body.

7. An aerosol type container in accordance with claim 5 in which said section expansion means comprises a plurality of slits in said body.