US3469744A

US3469744A - Aspirating type fluid dispenser

Info

Publication number: US3469744A
Application number: US684985A
Authority: US
Inventors: Douglas F Corsette
Original assignee: Diamond International Corp
Current assignee: Silgan Dispensing Systems Corp
Priority date: 1967-11-22
Filing date: 1967-11-22
Publication date: 1969-09-30
Anticipated expiration: 1986-09-30
Also published as: FR1592764A; NL6815569A; GB1212778A; BE723642A; DE1809777A1

Description

D. F. CORSETTE ASPIRATING TYPE FLUIDQISPBNSER Filed Nov. 22, 1967 f INVENTOR @o4/GMS Cafesfms M, Qua@ a/e-J ATTORNEY;

l vinili larifltllllvlIl/llln 4/ Sept. 30, 1969 United States Patent() us. c1. zzz-193 '12 Claims ABSTRACT THE DISCLOSURE An. aerosol dispenser of the aspirating type in which the propellant is stored within a cartridge, the cartridge and the product to be dispensed both being housed with the product container. Discharge lof the propellant 3,469,744 Patented Sept. 30, 1969 ice l pensers of the type above described, because of the fact that in this type of dispenser only the propellant cartridge normally will be capable of withstanding any substantial internal pressure and the container may therefore explode if subjected to internal pressures of the order which frequently prevail within conventional aerosol and pressurized dispensers.

through a hollow valve stem to` an aspirating nozzle, in- Y duces a flow of product through a separate passage to and through the nozzle. An annular diaphragm valve within the outer container, having its opposite surfaces exposed to atmospheric pressure and to the internal pressure'within the product container respectively, normally maintains the product out of communication with the atmosphere, but is actuated automatically in response to pressure dif. ferential on its said surfaces, to admit air into and to release overpressures from the product container.

Background This invention relates to an improved venting means for a dispenser equipped portable container of the class in which the dispenser extends in uid tight manner into the container interior through an opening in the container wall and is selectively operable to withdraw the product from the container. The dispenser or dispensing unit may be of a generally conventional nature such as a manually actuated reciprocating pump or an aerosol dispenser of the spirating type, though the invention has particular utility when employed with a dispenser of the type last mentioned. Accordingly, in the preferred embodiment hereinafter specifically described and illustrated, the invention includes such an aspirating aerosol type dispenser, though in its broader aspect it is by no means limited to use with a dispensing unit of this particular type as distinguished from a conventional dispensing pump or the like.

I such dispenser equipped containers it is generally necessary to admit air from the atmosphere into the product container to replace the dispensed portion of the product. At the same time, it is desirable to maintain the product normally out of communication with the atmosphere during periods of non-use in order to prevent product leakage or evaporation during shipping and storage. These ends have been achieved in the prior art, as exemplified for instance in the United States patents to Roth No. 3,289,949 granted Dec. 6, 1966, and Corsette United States Patent No. 3,228,347 granted Jan. 11, 1966. In each of these, however, the venting valves or means are opened only during dispensing of the product and are lacking in provision for equalization of pressures within and exteriorly of the container at other times.

It is, of course, desirable to admit atmospheric air into the product container to compensate for any substantial decrease of pressure therein such as might occur through temperature changes. It is further desirable to provide for automatic release during such periods of inactivity of any excess pressures which might occur within the product container from such causes as increase of temperature and in the case of an aerosol dispenser of the type here involved, leakage of propellant into the product container. The release of such excess pressures is of particular importance in connection with aerosol dis- Summary In order to achieve these additional ends, the improvements contemplated by the present invention comprise the incorporation in which a dispenser equipped container of an air admission and excess pressure relief valve, for normally maintaining the product out of communication with the atmosphere, but actuated automatically and independently of the dispenser, in response to unbalanced pressures of the atmosphere and the interior of the product container, for either admitting atmospheric air into the container or of permitting release of excess pressures from the container.

Brief description of the drawings In the preferred embodiment of the invention shown by way of exemplication in the accompanying drawings:

FIGURE 1 is a vertical cross section through the upper portion of an aspirating type aerosol dispenser in accordance with the invention, showing the various parts as they appear when the pressures within and exteriorly of the product container are substsantially balanced and the propellant and product discharge passages, as well as the venting passages are closed.

FIGURE 2 is a view generally similar to FIGURE 1 showing the positions assumed by the various parts in their dispensing positions, but omitting the protective overcap.

FIGURE 3 is a view similar to FIGURE 2, showing the venting valve in the position which it assumes when releasing ex-cess pressure of the interior of the product container, the propellant and product discharge passages being closed by their respective valves.

Description of the preferred embodiment Referring now in detail to the accompanying drawings, the numeral 10 therein designates the outer or product container, which may be formed of any of a variety of plastic or other materials, of various sizes and configurations, since in use it will not be required to withstand any substantial internal pressures. The open upper end of the container is preferably circular in plan, and is sealed by a generally conventional end closure cap 12, here shown as having an upwardly extending and reversely curved marginal wall 14 snugly receiving the peripheral end portion of the container to position the top wall 16 of the closure cap inwardly from the container mouth. The closure cap is firmly secured within the container by expanding its marginal wall 14 at its juncture with the top wall 16 to project radially beneath an undercut annular shoulder 18 within the container mouth. There also may be provided a removable overcap 19, as shown in FIGURE l, to cover and protect the dispensing means later described.

Supported within the product container 10 through the central opening 20 in the top wall of the cap 12 is a suitable product dispensing unit, exemplified by an aspirating type of aerosol dispenser including a cartridge 21 for holding a supply of a suitable propellant fluid, such as Freon or a pressurized gas. The cartridge includes a cylindrical neck portion 22, formed at its upper end with an external bead 24 which is sealingly secured within a downwardly opening socket 26 in the closure cap. In order to inmly support the cartridge from the container cap, the base of the socket is snugly radially com- 3 pressed around the cylindrical neck portion 22 as at 28, just beneath the annular bead 24 of the neck.

The opening defined by the tubular cartridge neck is aligned axially with the opening through the socketed portion of the closure cap, for sliding reception through said openings of a dispensing actuator member,here in the form of a valve stem 34 which preferably is guided through the cap opening 20.

Associated with the valve stem 34, for control by axial movement of the valve stem, are normally closed propellant and product discharge 'valves both housed within the propellant cartridge and generally designated 36 and 38 respectively. The propellant discharge valve 36 is of conventional structure, including a centrally ported rigid partition 40 having its outer periphery supported in an annular groove 42 in the cartridge wall between

annular sealing gaskets

44 and 46, of which the gasket 46 comprises the outer periphery of a unitary resiliently deformable valve member, the central portion of which comprises a valve body 48 supported from the gasket 46 by a comparatively thin annular perforated flexible web portion 50 for axial movement into and from seating relation with the lower end of a vcylindrical sleeve 52 defining the propellant discharge valve port through diaphragm 40. The valve 36 is formed of a resiliently flexible and somewhat elastic material such as natural or artificial rubber, the elasticity of which normally urges the valve body into seating relation with the port 52 as does the pressure of the propellant. When the valve body 48 is unseated, the perforations 51 through its ilexible web portion will establish communication between the cartridge interior and the propellant discharge port 52. The lower end of the valve stem 34 extends and is guided for movement through the propellant discharge port S2 so that downward pressure on the stem is trans` mitted to the central valve body 48 to unseat same.

Formed through the valve stem is a propellant discharge passage 54 which opens radially outwardly through the lower end portion of the valve stem at 56 (in FIG- URE 2) just above the valve body 48 to permit entry of propellant into said passage when the valve body is unseated.

On the upper end of the valve stem is a spray head 58 which may be frictionally fitted or otherwise secured on the stem in fluid tight manner, and is formed to present a suitable surface 60 for the reception of actuating finger pressure. It will be understood that normally the valve stem and spray head are biased upwardly and maintained in a raised or upwardly projected position by the pressure of the propellant acting on the under surface of valve body 48, as well as by the resilient action of the body itself.

The spray head comprises a restricted discharge orifice 62 which communicates with the propellant discharge passage 54 of the valve stem. Also, the spray head and valve stem 34 conjointly deiine part of a product discharge passage 64 opening into the constricted portion of the discharge nozzle closely adjacent the restricted propellant discharge orifice 62, so that the propellant will cause a substantially reduced pressure at the juncture of the product passage and nozzle to thus induce by aspiration and upward flow of product to the nozzle to be entrained in the propellant and discharged therewith from the nozzle in the form of a line suspension.

The product discharge passage 64 further includes the upper end compartment 66 and the product within the outer container 10. The product discharge valve 38 includes annular flexible member 70 snugly slidably encircling the valve stem 34 in sealing engagement therewith within the compartment 66. The outer periphery of member 70 is sealed to the propellant cartridge as by sealing reception within an annular groove 72 between the upper end of the cartridge and the relatively spaced annular ledge 74 therein. Beneath the valve member 70, the valve stem is formed with an enlargement having an upwardly directed annular sealing surface 76 for flush sealing engagement with the valve member in the raised and closed position of the valve stem.

The product passage 64 through the valve stem opens radially outwardly from the stem to define an intake port 78 at an axial location such that in the raised position of the valve stem such port is sealed off from the compartment 66 by the encircling valve member 70, in conjunction with the upwardly presented annular sealing surface 76 of the stem.

However, depression of the valve stem 34 by linger pressure on the spray head 58 will force the valve stem downwardly through the valve member 70, exposing the port 78 thereof `within the compartment 66 for reception of the product and for passage of said product to the discharge nozzle under the aspirating action induced by the propellant.

Venting and pressure release The invention comprises a novel iiexible annular diaphragm 80 slidably encircling the cylindrical neck portion of the propellant cartridge. The outer periphery of this diaphragm is sealingly clamped between the lower face of the closure cap top wall and an annular ledge 82 formed on the inner wall of the product container.

A pressure relief passage is provided by the radial clearance 35 between the neck interior and the valve stem 34, and the pressure relief port 84 through the side lwall of the neck. Port 84 is located to be slightly above the inner periphery of the diaphragm 80 when the pressures on opposite sides thereof are substantially balanced as in FIGURE 1. In this position, the pressure relief port 84 is out of communication with the product within the container, being separated from the product by diaphragm valve 80. The pressure relief passage 35 communicates with the atmosphere through the comparatively slight clearance space between the valve stem and the central opening 20 of the closure cap 12.

The upper face of the diaphragm valve 80 is exposed to atmospheric pressure through a vent opening 86 in the closure cap while the lower face of the diaphragm valve 80 is exposed to the .pressure which prevails within the product container 10. It will be noted that the top wall of the container cap is dished or domed upwardly at its central portion, to permit upward flexing of the daphragrn valve 80 without interference, while the outer periphal portion of the same wall is arranged for axial abutment with the diaphragm valve to maintain the latter in sealing engagement with the annular ledge 82. The vent opening 86 is preferably formed through this latter portion to be sealed by the valve 80 in both the balanced and overpressure conditions of the valve.

Thus, in the operation of the invention, in the event the pressure of the product compartment (outer container) substantially exceeds the pressure of the atmosphere, the inner periphery of the diaphragm valve 80 will be deflected upwardly to a location above the pressure relief port 84, as in FIGURE 3, placing said port in communication with the interior of container 10. The pressure may then escape through relief port 84 into the pressure release passage 35 around the valve stem for discharge until the pressures within and exteriorly of the product container approach equilibrium. It is desirable t0 provide the product container with an overcap such as 19 to prevent the inadvertent discharge of the device in shipping and handling and to catch and retain the discharged product if product overpressure is released with the container inverted. As `the said pressures approach equilibrium, the inner periphery of the diaphragm valve will move back downwardly across the pressure release port 84 in response to atmospheric pressure entering through port 86 to seal same against the loss of further product, and from the resilient memory of the valve 80.

The foregoing pressure relief function will occur when the excess pressure is caused by leakage of the propellant into the product container, due to a defective propellant valve or for any other reason, as well as when the excess pressure is caused by temperature variations, variations in external atmospheric pressure etc.

On the other hand, if the pressure within the container is below atmospheric, through dispensing of the product, or contraction of the product due to temperature changes, air entering the container through the vent opening 86 or through passage 35 and port 84, or both will deflect the inner periphery of lthe diaphragm valve 80 downwardly around the cylindrical neck portion 22 of the cartridge. In so doing, it will slightly stretch the inner periphery of the diaphragm valve 80, to provide a slight gap between it and the cylindrical neck portion through which the air may flow inwardly to the interior of the product container. Again, when the pressures on opposite sides of the diaphragm valve 80 approach equilibrium, its inner periphery will sealingly reengage around the neck portion 22 below the port 84 to thus disrupt the communication between the product container and the atmosphere.

Normally, it will be desired to permit ready inux of air to replace withdrawn product, whenever the product pressure drops slightly below that of the atmosphere. On the other hand, to avoid unnecessary product loss it will generally be desirable to avoid release of excess pressure from the product container until such pressure substantially exceeds atmospheric pressure. The generally downwardly converging and tapered conical rim 88 defining the inner periphery of the diaphragm is well adapted to achieve these ends. Obviously, its downward convergence will permit it to ex away from the valve stem incident to relatively minor increases in atmospheric pressure, but pressure exerted on its under side from the container interior will urge the said conical periphery more tightly into sealing engagement with the valve stem, whereby the entire inner peripheral portion of the said valve must be deected axially upwardly a substantial distance, under a correspondingly greater pressure, to uncover the pressure release port 84.

It will be appreciated that operation of the valve 80 is fully automatic in response to differential pressures on its opposite sides, and is completely independent of the positions of the product and propellant discharge valves.

Having thus described the invention, I claim:

1. In combination a product container having a wall formed with an opening therethrough, a product dispensing unit extending through said opening and selectively operable to withdraw product from `the container, said dispensing unit having a cylindrical exterior valving portion within the container, a flexible annular diaphragm within the product container encircling said cylindrical valving portion at a level above the product in said container, the outer periphery of said diaphragm being secured in uid tight manner to the product container, means for admitting air from the atmosphere into the container above said diaphragm, the lower side of said diaphragm being exposed to the pressure within vthe container, the inner periphery of the diaphragm being disposed for axial displacement along said valving portion responsive to variations in the differential pressure on opposite sides thereof, said diaphragm and valving portion having fluid tight engagement with each other in the position assumed by said diaphragm when opposing pressures on opposite sides of the diaphragm are balanced, said diaphragm and said valving portion being mutually conformed to permit downward flow of air therebetween when atmospheric pressure exceeds the internal pressure below the diaphragm in the con-tainer.

2. The combination defined in claim 1 in which said diaphragm when in its normal position of balance between the opposing pressures lies in substantially a radial plane of said cylindrical valving portion, the diaphragm being of an elastomeric material whereby its inner periphery may stretch slightly incident to downward displacement thereof to provide a clearance between said inner periphery and the cylindrical valving portion through which air from the atmosphere may ow into said container for pressure equalizing purposes.

3. The combination defined in claim 1 in which said wall of the product container is dened by a closure cap applied to the container and providing said opening, said wall being of circular configuration with the outer peripheral portion thereof normally in flush contiguous relation to the outer periphery of said diaphragm, said outer peripheral portion of the wall being formed with a vent opening therethrough, said diaphragm normally closing the vent opening when the internal pressure within the product portion of the container equals the atmospheric pressure, but being capable of flexing away from and uncovering said opening when said atmospheric pressure exceeds the internal pressure of the container.

4. The combination of claim 3 in which said diaphragm has its outer periphery sealingly clamped between said closure cap wall and an opposing annular shoulder formed within the container.

5. The combination defined in claim 1 in which said dispenser is provided with a pressure release passage communicating with the atmosphere and opening into the product containing portion of the container interior through a port in the outer surface of said cylindrical valving portion of the dispenser unit, said port normally being located above the diaphragm in the position assumed by the latter when the opposing pressures thereon are balanced, the inner periphery of said diaphragm being displaceable axially upwardly along said cylindrical valving portion to uncover said port when the pressure within the product containing portion of the container substantially exceeds atmospheric pressure.

6. The combination of claim 5 in which said cylindrical valving portion comprises a tubular neck of the product dispensing unit defining an opening extending axially therethrough, the upper end of said opening communicating with the atmosphere and said port ex-tending radially through the said neck from the said opening to the exterior thereof.

7. The combination of claim 6 wherein said dispensing unit comprises an actuating member disposed for axial movement through said tubular neck of the container and spaced from the interior of said tubular neck to dene between said neck and said actuating member a pressure relief passage communicating with said port and with the atmosphere.

8. The combination defined in claim 7 in which said diaphragm includes a generally downwardly converging and tapered rim defining its inner periphery, whereby said rim may flex readily away from the said cylindrical valving portion in response to relatively minor excesses of the atmospheric pressure over the pressure prevalent within the product portion of the container, while pressures exerted on the under side of said diaphragm will urge said rim radially into sealing engagement with the said valving portion to require substantial upward deflection of the diaphragm before the said pressure release port is uncovered.

9. In combination, a product container having a wall formed with an opening therethrough, a product dispensing unit extending through said opening and selectively operable to withdraw product from the container, said unit having a cylindrical external valving portion within the container, a flexible annular diaphragm within the container encircling said cylindrical portion substantially in a radial plane thereof at a level above the product, the outer periphery of said diaphragm being secured in fluid tight manner to the container, the upper face of said diaphragm being exposed to atmospheric pressure and the lower face thereof being exposed to the internal pressure of the container, the inner periphery of the diaphragm being disposed for axial displacement along said cylindrical valving portion responsive to relative variation in the pressures on its opposite faces, said diaphragm and said cylindrical valving portion having fluid tight engagement with each other in the axial position assumed by said diaphragm when the pressures on its opposite faces are balanced, said cylindrical valving portion being formed with a pressure relief passage communicating with the atmosphere with the lower end of said passage delining a port in the radially outwardly presented surface of the cylindrical valvng portion at an axial location which is normally above the inner periphery of the diaphragm when the latter is subjected to substantially balanced forces on its opposite sides, the inner periphery of the diaphragm being moveable axially along said cylindrical valving portion to uncover the port when the pressure within said container substantially exceeds atmospheric pressure.

10. The combination defined in claim 9 in which the inner periphery of the diaphragm comprises a generally downwardly converging conical rim, the inner periphery of which sealingly engages the cylindrical surface of said cylindrical valving portion.

11. The combination of claim 9 in which said cylin drical valving portion comprises the tubular neck of the product dispensing unit, the said port extending through said neck from the interior to the exterior thereof, an

actuating element for the dispenser being disposed for axial movement through the interior of said neck and having suicient clearance therewith to dene therebetween an annular passage placing said port in communication with the atmosphere.

12. The combination of claim 11 in which said actuating member comprises the valve stern of an aerosol valve.

References Cited SAMUEL F. COLEMAN, Primary Examiner NORMAN L. STACK, JR.,'Assistant Examiner U.S. Cl. X.R.