Dispenser valve assembly for a pressurized aerosol dispenser

Abstract

The invention concerns a modified valve stem portion of a movable valve body and a modified actuator button for use in a pressurized aerosol dispenser. A valve stem of the movable body and an actuator button member conjointly provide an improved product flow rate control or metering passageway and an improved expansion chamber which are both readily accessible for cleaning. The tubular valve stem portion of the movable valve body includes a reduced diameter cylindrical tip and an upwardly open transverse slot in the tip in communication with the bore of the stem. The actuator button includes a cylindrical valve stem receiving socket in its underside and a centrally disposed, cylindrical valve stem closure plug in the socket in spaced relation to the side walls of the socket.

Description

BACKGROUND OF THE INVENTION

The present invention relates to pressurized aerosol dispensers. More particularly, it relates to a means for controlling the flow rate of a fluid product dispensed from a pressurized aerosol dispenser.

Pressurized aerosol dispensers are product containers having a valve and a valve-actuating button which ordinarily includes a discharge orifice through which the product is dispensed when the valve is opened. The product is pressurized within the container by means of a volatile propellant. U.S. Pat. No. 2,631,814 to Abplanalp is exemplary of these dispensers. The present invention deals with the actuator button and the upstanding hollow valve stem portion of a valve, such as is shown in the Abplanalp U.S. Pat. No. 2,631,814.

Heretofore, the flow rate of product through the valve was controlled by a restriction somewhere along the product flow path. Usually this flow rate controlling or metering restriction is the valve orifice of the valve body. This is the orifice which communicates the interior of the product container with the hollow interior of the valve stem when the valve is open. The valve is closed by blocking this orifice with an elastomeric gasket or washer when the movable valve member is in the closed position. Usually the valve orifice is located inaccessibly deep within the valve unit.

Some products, such as paint, harden between uses of the dispenser or they may contain particles. When the flow rate metering restriction is the valve orifice, this restricted passage may become clogged or blocked with dried product or particles. Since the user cannot access this small passage for clearing it, the dispenser becomes prematurely useless with product trapped inside.

SUMMARY OF THE INVENTION

The present invention puts the flow rate metering or control restriction in a location where the user can easily clean or clear it, thereby permitting full consumption of the product.

The preferred embodiment of the present invention is an improvement in an aerosol pressurized dispenser having an actuator button of the type having a valve stem receiving socket and a dispensing valve unit of the type having an upstanding tubular valve stem integral with the movable valve body. The actuator button and valve stem are conjointly configured to provide an improved product flow rate control or metering passageway and an annular chamber which are easily accessible to the user for cleaning or unclogging. The actuator button and valve stem are also conjointly configured for assembly in any rotational orientation with respect to each other, thereby avoiding any need for indexing during assembly.

Toward these ends and others, the hollow valve stem portion of the movable valve body includes a reduced diameter, cylindrical tip segment and an upwardly open slot extending transversely through the wall of the stem in the tip segment and the actuator button includes a cylindrical valve stem receiving socket in its underside and a cylindrical valve stem closure plug centrally disposed in the socket in spaced relation to the side walls of the socket.

BRIEF DESCRIPTION OF THE DRAWING

The drawing is an elevational view in vertical section of the actuator button and movable valve body of a pressurized aerosol dispenser valve assembly showing a preferred embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawing, a preferred embodiment of the present invention comprises a movable valve body 10 and an actuator button 20 which are configured to conjointly provide an improved product metering passageway 1 for controlling the flow of a dispensed fluid and an improved annular chamber 2 for supplying the controlled flow of fluid product to a discharge orifice 25. More particularly, the actuator button 20 and the valve stem portion 11 of the valve body 10 provide a readily accessible metering passageway 1 and annular chamber 2 to permit cleaning when the user is dispensing a product prone to clogging, such as paint.

The valve stem 11 may be the upstanding, hollow tubular valve stem of an aerosol discharge valve unit of the type disclosed in U.S. Pat. No. 2,631,814 to Abplanalp, although the present invention is also applicable to other pressurized aerosol dispensers employing separable actuator buttons and valve stems.

The movable valve body 10 of the present invention (in common with known aerosol valves, such as Abplanalp U.S. Pat. No. 2,631,814) comprises an upstanding hollow tubular stem portion 11 integral with a main body portion 12. The hollow stem has an axial internal bore 13 in communication with one or more valve orifices 14 located in a reduced diameter neck about which a resilient annular gasket is placed such that the valve orifices 14 are blocked by the inner margin of the gasket. A more complete explanation of the foregoing is found in Abplanalp U.S. Pat. No. 2,631,814.

The modified valve stem 11 of the present invention has a reduced diameter tip segment 15 defined by an annular shoulder 16. The valve stem 11 is frictionally received in a valve stem receiving socket 21 on the underside of the actuator button 20. The socket 21 is cylindrical and has a diameter to provide a tight fit on the major diameter of the valve stem 11. The reduced diameter tip 15 cooperates with the receiving socket 21 to provide an annular chamber 2 which encompasses the tip 15 of the stem 11.

An upwardly open transverse slot 17 extends radially out through the valve stem wall 18 at the upper end of the tip 15. Slot 17 communicates the internal bore 13 with the annular chamber 2 surrounding the tip 15. Slot 17 constitutes the product flow rate control or metering restriction.

The valve stem receiving socket 21 of the actuator button 20 includes a shallow closure plug 22 which depends centrally from the interior end wall of the socket 21. The closure plug 22 enters the internal bore 13 of the valve stem 11 when the button 20 and stem 11 are assembled. Desirably, the closure plug 22 has a slight taper to facilitate this assembly. The plug 22 seals off the valve stem bore 13 from communication with the annular chamber 2 thereby insuring that transverse slot 17 in the end of the valve stem 11 is the sole communication between the stem bore 13 and the annular chamber 2. This construction permits some tolerance in dimensioning or assembly of the button 20 and valve stem 11. Without closure plug 22, product could leak around the top end of the valve stem 11, thereby increasing the product flow rate over the rate desirably dictated by the flow characteristics of transverse slot 17.

Although the discharge orifice 25 may be molded directly in the actuator button 20 the discharge orifice may be formed in a separate piece which is assembled with the body of the actuator button 20. In the embodiment of the present invention illustrated, the discharge orifice 25 is located in a nozzle insert 30 having a tubular portion 31 which is frictionally retained in an appropriate bore 23 in the body of the actuator button 20. Such inserts 30 can be provided with a variety of configurations appropriate to the particular product to be dispensed. For example, inserts can provide fan-shaped sprays for directionally dispersing paints or other coatings or mechanical break-up configurations to assist in nebulization of aqueous products, such as spray starch.

The other details of the actuator button 20 and movable valve body 10 shown are conventional and well known and do not require further elucidation.

The actuator button 20 and the movable valve body 10 are assembled by frictionally receiving the cylindrical valve stem 11 of the valve body 10 in the cylindrical valve stem receiving socket 21 of the button 20. When so assembled, a product flow passageway is established leading from the valve orifices 14 through the valve stem bore 13, thence through the transverse slot 17 at the upper end of the stem 11 and into the annular chamber 2. Annular chamber 2 is in communication with the tubular portion 31 of the insert 30 to discharge pressurized product through the discharge orifice 25 of the insert 30.

Closure plug 22 in conjunction with the configuration of the tip 15 of the valve stem 11 requires that all product flow through transverse slot 17. The effective cross-sectional area and configuration of slot 17 are chosen to produce a flow rate suitable for the product dispensed. By controlling or metering flow rate by slot 17, the valve orifices 14 can now be made larger than in the prior valves which accomplished the flow rate control function by selection of appropriate sizes for the valve orifice. By permitting larger valve orifices, the present invention provides less opportunity for clogging the valve since particles in the product which could block the valve orifices of a prior valve can pass freely through orifice 14 of the present valve. Clogging due to particles in the product or due to drying of residual product between uses of the dispenser will affect the slot 17 of the present invention. However, since slot 17 is external, it it readily accessible for cleaning or clearing by simply removing the button 20 and wiping or washing with solvent. A clogged dispenser utilizing the present invention can be made operative, whereas a dispenser of the prior construction tends to clog at an inaccessible internal valve orifice and therefore remain inoperative. The discharge orifice 25 is also accessible for easy cleaning.

Annular chamber 2 formed by the annular shoulder 16 and the reduced diameter tip 15 in conjunction with the cylindrical valve stem receiving socket 21 of button 20 serves two purposes. Chamber 2 forms an expansion chamber interposed between the flow restriction slot 17 and the relatively small discharge orifice 25 in insert 30. An expansion chamber aids in converting liquid product into a dispersion of spray droplets. Since chamber 2 is annular, no relative orientation or indexing of the button 20 with respect to the valve stem slot 17 is required thereby simplifying assembly for the manufacturer and also allowing the user to remove and replace the button for cleaning purposes without worrying about orienting the two pieces. Since the entrance to the tubular portion 31 of the insert 30 is below the slot 17 of the stem 11, these passages do not align and the flow rate is uniform at any rotational orientation of button and stem.

From the foregoing, it is apparent that the product metering slot 17 and the annular expansion chamber 2 provided by the preferred embodiment of the present invention are both fully exposed by disassembly of the actuator button 20 from the valve stem 11. This provides easy access to both the slot 17 and the chamber 2 for cleaning or unclogging should it become necessary. In fact, the very act of disassembly may break loose and dislodge detritus clinging to and clogging the passageway 1 or chamber 2.

While the actuator has been described as an actuator button 20, it should be understood that any actuator, such as the hinged tab of an actuator dome, which is configured in accordance with the present invention may be used in forming the dispensing valve assembly of the present invention.

Claims

What is claimed is:

1. In a dispensing valve assembly for a pressurized aerosol dispenser, said valve assembly including;

a movable valve body having an upstanding valve stem with a coaxial product passageway and a valve orifice in communication with the stem passageway, and

a valve actuator having a valve stem receiving socket for removably engaging said valve stem and having a discharge orifice in communication with said valve stem passageway, the improvement which comprises:

a central plug in said valve stem receiving socket, said plug closing the upper end of said valve stem passageway,

said valve stem including an upper portion of smaller external diameter than the lower portion to define an annular chamber within the valve stem receiving socket, said annular chamber being in communication with said discharge orifice, and

an upwardly open slot extending through said upper portion between the valve stem product passageway and the annular chamber to provide the product flow rate controlling restriction of the valve assembly.

2. The valve assembly of claim 1 wherein an annular shoulder is interposed between the upper and lower portions of the valve stem.

3. The valve assembly of claim 1 wherein the slot extends radially of the valve stem.

4. The valve assembly of claim 1 wherein the slot intercepts the upper region of said annular chamber and the discharge orifice is in communication with the lower region of said annular chamber.