IL31897A - Plug valve assembly for dispensers of fluid products - Google Patents

Description

npi^n α*3ρηπ nay o inoim onoa © nsiya Plug valve assembly for dispensers of fluid products CIBA-GEIGY A.G.

C. 30203 This invention relates to plug valve assemblies.

There is already known in the ar 'a pushbutton dispenser for dispensing a fluent product constituting an active agent in fractional amounts and in a spray, by means of a propellent gas under pressure held in a propellant cartridge placed inside the product container which contains said fluent product and which is carried on said support, which support is integral with a cover which seals off the aforementioned product container. Th s integral support and cover contains a high pressure obturating means for the propellant cartridge and a low pressure obturating means controlling, respectively, the passage of the product from the container to the pushbutton spray nozzle and the passage of air from the outside to the inside of the product container. A stem which conducts the propellant and the product in the direction of the spray nozzle is slidably mounted in said support and controls the aforementioned obturating means. ¾is dispenser has the high pressure obturator mounted in the bottom of the support which is held therein by a substantially rigid retaining ring.

The high pressure obturator is positioned in a recess in the support which opens toward the propellant cartridge, said obturator being held in said recess by means of the retaining ring member which also forms part of the closure for said propellant cartridge. ¾e retaining ring member consists of a separate annular part which is force into a recess in the support and has a downwardly and outwardly extending portio positioned between the support and the collar of the propellant cartridge. ihe high pressure obturator is a thick gasket fitted' sufficiently tightly around the stem so that when the lateral passage in the stem is within the gasket, the engagement is sufficiently tight to prevent passage of propellant between the stem and the gasket, and thus through the hollow stem through the lateral passage.

In practice, it has been found thajt this gasket' must engage the stem so tightly that it is -unnecessarily difficult to depress the stem. Moreover, since the gasket is the only place where there is any contact between the stem and the support, it must act as a bearing as well as a gasket, and because it must be sufficiently resilient to seal around the stem, it permits the stem to tilt laterally in an objectionable fashion. This is undesirable in an apparatus of this type.

It is an object of the present invention to provide a stem and support which overcomes these drawbacks and permits easy operation of the stem, yet at the same time provides a good sealing effect and enables a portion of t te stem to be in bearing contact with the support body.

According, therefore, to the present invention there is provided a plug valve assembly for dispensers of fluid products adapted to be attached to a product container for containing the fluid product to be dispensed and adapted to accommodate a propellent in a separate cartridge within the product container, said plug valve assembly comprising a hollow valve stem, a pushbutton actuator on the upper end of said stem^nd having a nozzle therein communicating with said hollov? stem, a cap member adapted to fit over a product container and having an aperture therein through which the hollow stem is movable against the pressure of a resilient element, a support secured to the under side of said cap and having a hollow central portion through which said hollow stem is movable, a dip tube secured in said support and opening into said hollow interior, a fluid product flow path through said hollow stem exteriorl of the hollow thereof from a point adjacent said hollow interior, a low-pressure flexible gasket in said assembly through which said hollow stem passes obturating said fluid product flow path between said fluid product flow path and said hollow interior in the non-dispensing position of the valve assembly, said support having a downwardly open recess therein, a high pressure flexible annular gasket in the bottom of said recess through which said hollow stem passes, retaining ring means retaining said high pressure flexible gasket in the bottom of sai xecess and adapted to be connec ted to the propellant cartridge, said stem having a lower cylindrica portion and said support having a bore therethrough between said hollow interior and said downwardly open recess in which said cylindrical portion is in sliding bearing engagement, said stem further having a neck portion in the lowe end of said cylindrical portion* which neck portion comprises a reduced diameter cylindrical portion whose upper end is disposed below the bottom of the hollow of the stem, a conicall tapered portion joining the upper end of said reduced diameter cylindrical portion to said stem cylindrical portion and a downwardly and outwardly inclined portion joining the lower end of said reduced diameter cylindrical portion to the bottom portion of said stem* said stem having downwardly extending passages therein from the hollow of said stem to said neck portion, said passages extending substantially parallel to the axis of the stem* and opening out of the said neck portion in the region of the conically tapered portion, at least a par of each opening being in the conically tapered portion, the thickness of said high-pressure flexible annular gasket and the vertical dimension of said reduced diameter cylindrical portion being so dimensioned as to cause said high pressure gasket, in the non-dispensing position of the valve assembly, to be bent inwardly into saidjecess of said support and to be deformed into sealing engagement with said downwardly and outwardly inclined portion and, simultaneously, with said conically end of the stem and the surrounding parts of the embodiment of Fig. 1; Fig. 5 is a view similar to Fig. 1 showing the p rts in the dispensing positions; ^i . 6 is an enlarged fragmentary sectional view similar to Fig. k showing a modification of the stem according to the invention; Fig, is a sectional view taken on line 7-7 of Fig. 6> Fig. 8 is an enlarged fragmentary sectional view similar to Fig. k showing another modification of the stem according, to the invention; and . c Fig. 9 is an enlarged fragmentary sectional view similar to Fig. showing still another modification of the stem according to the invention. , : .

— Referring to Figs. 1 and 2 of the attached drawings, the dispenser comprises a product container C which is adapted to hold a flowable product such as a liquid or a finely divided powder. ¾e product container is closed by a cover 1 from which depends the plug valve assembly. A propellant cartridge depends from the plug valve assembly into the interior of the container C. ¾e cover 1 is made, for example, of plastic material, to which support 2 is attached, these parts mutually abutting each other at joint 33 where they fit together and hold therebetween a flexible annular .low pressure sealing gasket which is the lov; pressure obturator for the active agent and the low pressure obturator for the admission of air to the product container C from the ! outside. ¾e cover 1 and support 2 are attached to each other' along the interfitting joint 33, nnd in the embodiment shown, the cover 1 has a depending flange la closely surrounded by an upwardly projecting flange. 2a on the top of body 2, the depending flange la abutting a seat 2b on the top of the body 2. ¾ie joint is connected by ultrasonic welding.

Cover 1 has a central opening 5 -"*nd support 2 has an axial valve cup 6 therein, which opening and valve cup are traversed during the axial stroke of valve stem 7 connected to a valve actuator in the form of a pushbutton 8 containing o nozzle insert 9 having a renturi type spray nozzle therein. Nozzle insert 9 is set into cavity 11 in the . head of pushbutton 8. A bore 12 is provided in the bottom of body 2 between valve cup: and a diverging recess 13 in the base of support 2. . · A flange 2k on valve stem 7 is urged upwardly by a spring 5 around valve stem: 7, an^ s positioned between flange.2k and the bottom of cup 6. 'Th s spring acts to press the flange 2^ upwardly so that the flexible lip of gasket k is held between a truncated cone- shaped seat 26 on -flange 2k t cambered as shown in Fi . 1, and an annular projection 28 around the edge of opening 5 n cover 1. This .. provides a tight closure of valve cup 6 with respect to opening 5 and n tight' closure of passage 32 from the depending, portion into the spac beneath cover 1. In the raised position shown in ?ig. 1, there is a . space between the inner edge of gasket k .and the tapered lower end- of depending wall 22 on the pushbutton. ¾is opens, into the channels 21 described hereinafter, which in turn open into an annular groove 3 (or a plurality of orifices 23 in the v/all of stem 7, Pushbutton 8 , which caps valve stem 7» has, two coaxial sockets ! at the base thereof; an outer socket 73, defined by depending wall 22 • and which fits tightly around valve stem » "nd an inner socket 7k which receives the end 5 of stem 7. , %e extents to which sockets 73 and 7 * can be forced along valve stem 7 is limited by an annular shoulder 76 at the base of fins 72 defining between them channels 21, along -the outside of the stem 17. ^h channels open out of the stem through apertures 23· The surface 78 of said flange 2k opposite gasket k is straight and serves as a support for spring 25, but this flange 2k also serves as a movable stop for the pushbutton assembly.

Into valve cup 6 opens the upper end of dip tube 29, force- fitted in a bore 31 in support 2, d which is for the passage of the active agent. us shown more clearly in Fig. the high pressure obturator is in the form of an annular flexible gasket 15 mounted in a dovmwardly opening recess 6 in support 2. The bore 12 from, the valve cup 6 opens into recess 6 , which in turn opens into recess 13· Valve stem 7 is made in one piece, for example, by molding, and has an axial bore 17 with the conical head l8 closing one end thereof. The valve stem 7 of the embodiment of Figs, 1-5 has a lower cylindrical portion ?a which is slidable in bore 12 and is guided in its vertical movement in bore 12.

At the inner end of the stem 7 is a neck portion having a reduced diameter cylindrical portion 101 and a tapered portion 102 between the upper end of the cylindrical portion 101 and the cylindrical surface of I i ' the lower cylindrical portion of the stem and tapered at an angle of about 30° to the vertical. ¾e gasket portion further has a stepped portion having at least two steps 103 between the cylindrical portion 101 and thehead 18. ¾ee outside diameter of the head l8 is no greater than the diameter of the bore 12 in order to permit passage of the head through the bore 12 during assembly of the stem 7 of the body portion 2.

The bore 17 within the stem 7 is tapered near the lower end zone' thereof at 10k, and terminates above the cylindrical portion 101. A - ' i 1 2 plurality of downwardly extending passages 105, 105 , 105 extend from the inwardly tapered lower. end zone 104 and the bottom 10 a of the bore !) ■'. " ''( ;; .· ■ i 2 end · 17 to the surface of the cylindrical portion 101, 101 , 101 and opon ' : ( : in grooves 1 2 la-wwlly ..fpom sajLd-awriaoaii tiwrcMgh pa¾-te- 206, 106 , 106 . Because they extend straight down, they cut into the tapered portion of the inner wall surface 104 of "the bore 17.

The thickness of the gasket 15 and the inside diameter thereof are such that in the raised position of stem 7 the inner edge of the gasket 1 is pressed against the cylindrical portion 101, the upper edge is' deformed against the tapered portion 102, and the lower surface is deformed into tight engagement with step 103, thereby providing a tight seal of the ends of the passages 105.

Gasket 15 is held in recess 65 by a retaining ring 66. ¾e latter is an independent member of a flexible, deforraable and at least slightly resilient material, preferably metal, such as aluminium, somewhat in the shape of an inverted mushroom as shown in Fig. 5. ¾e wall of the ring is deformed by being bent concavely. '-¾e redlining ring has a central aperture 67 through which the cone-shaped head l8 of valve stem 7 extends. ¾e inner end of recess 65 is flared downwardly and outwardly, and the upper edge of the retaining ring 66 has the outer edge bevelled where it bears on gasket 15 and acts to give the gasket n generally upward and inward position in the raised position. of tho valve stem. This gives an upward bias to the valve stem.

A cylindrical cavity 7 is defined at the lower end of support 2 by an annular flange 68. ¾e lower end of retaining ring 66 is curved upwardly and_ outwardly to a flange 7 seated against the lower edge of annular flange 68. A sealing gasket (not shown) is held between the flange and collar 69 of propellant cartridge ½3. ¾e terminal portion of the propellant cartridge is bent so as to fit closely to the contour of annular flange 68 and flange ?1, forming a tight joint at the top of the propellant. cartridge' kj>. ¾e retaining ring 66 is made of a material which, in addition to being flexible, deformable and slightly resilient, is also impermeable with respect to the propellant contained in propellant cartridge . This prevents leaks as a result of ' permeability .through the material of support 2.

With (the. parts assembled and the product container C and cartridge hj> filled, when valve stem 7 is in the undepressed' position, as shown in Fig, 1, a .tight closure is insured between valve stem bore 17 and the cartridge by gasket 15, as described above, and between opening which c ommunicates with tho outside atmosphere as a result of a clearance provided for the sliding movement of the valve stem and the space under the cover 1, which is in communication with the upper surface of gasket k through at least one radial channel 32 in the lower face of the downwardly depending portion from cover 1.

A second embodiment of the .neck portion of the stem 7 is shown in Fig. '6 nnd 7,· ¾e neck portion has the. reduced diameter cylindrical portion 101a, , the. tapered portion 102a., and the stepped portion 103a, substantiall , the same as in the embodiment of Figs. 1-5· T e passages 105a, however, open out of the bottom end of the stem bore 17, and extend straight down and open out of the tapered portion 102a adjacent the cylindrical portion 101a. In this instance, the gasket 15a sh'quld be. thick enough to extend upwardly along the tapered portion 102a far enough to close the apertures at the ends of the passages 105a.

., When ;the valve stem 7 is depressed to the position shown in ¾ . the low pressure obturator, which is gasket t is deformed downwardly, being bent away from the downwardly depending portion of the cover.

This first opens the passage 32 to the atmosphere through the cover opening 5, and hen the inner edge is bent away from the apertures 23 at the lower ends of the channels 21 while bearing tightly against the tapered lower end of depending wall 22. Thus, the product flow path from the dip tube (29 through the cup 6 to the channels 21 and the nozzle in the. nozzle insert 9 is opened. The high pressure obturator in the . form of gasket 15 is likewise deformed and bent downwardly, the inner edge moving away from the apertures at the ends of passages 105, thus opening the propellant flow path from the cartridge 3 into the stem portion 17, to the. nozzle in the nozzle insert 9. It is preferred that the dimensions of, the apparatus be made such that tho opening of the apertures at the ends- of passages 105 take piece after opening of the apertures 23 to.the product flow path.

During, this movement, the stem is guided by the sliding bearing engagement of the cylindrical portion 7 in the boro 12 in the body portion 2 so that lateral tilting of the -stem is substantially prevented.

On release of the pushbutton, the spring 2 and the gaskets k ■ and 15 together urge the stem 7 upwardly to the initial position shown in Fig, 1, the closing of the various apertures taking place in the reverse order, i.e. the apertures at the ends of passages 105 closing first, then apertures 23 being closed by gasket *, and the passage 32. At the' uppermost position of the stem, apertures 2 are open to the atmosphere through the space between the inner edge of gasket and the tapered layer .end of wall 22. This enables the propellant still expanding in the propellant flow , ath to purge any product left in channels 21. .

, T e gasket 15 should have a thickness more than the vertical dimension of the cylindrical ; portion 101 of the stem 7 so that it will be deformed upwardly against the .tapered portion 102 and firmly deformed into. th steps 103 in order to provide a tight seal. t The upward inclination of the gasket 15 in th .closed position of the apertures insures that a toggle type action is produced during the movement of the stem. As the stem, moves downwardly, the material of the gasket 15 is compressed and deformed, even further than in the position shov/n in Fig, , until the neck portion moves past the level of the gasket 15· At this point, there will be a small downward force as the gasket material expands. In addition, the compression of th gasket material as the neck portion moves past the level position insures tight closing of the propellant flow path until after the apertures 23 in the product flow path have been opened. This is desirable in order to have the fluent product available as soon as the flow of propellant starts. ¾e steps 103, when the taper angle of tapered surface 102 or 102a is 0° A third embodiment of the neck portion of the stem ? is shown in Fig. 8. It is the same as that of Figs. 6 and 7 in that the neck portion has the reduced diameter cylindrical portion lOln, the tapered portion 102a, and the stepped portion 103a the same as in the embodiment of Fig. 8, ¾e passages 105a , however, open out of the bottom end of the stem bore 17 , and extend straight down and open. out of the tapered portion 102a at a point spaced along the tapered surface 102ja a distance 106 from the cylindrical portion 101a.

It has been found that it can be advantageous to use a somewhat thinner flexible gasket than that shown in Figs. 1-8 , such a gasket flexing easier during valve actuation. However, when this is donet it .10.68 is necessary to change the configuration of the valve stem slightly to that shown in Fig. 9. In Fig, 9 the parts are generally the same as in Figs. 6-8 , except that the angle B of the tapered portion 102b is between JO and ?0° , preferably about ^0° , to the vertical. With this change, the steps can be eliminated, and an unstepped eloping surface 103b can be usedi Otherwise the construction is the same, the stem having the cylindrical portion 101b with the passages 105b opening out of the sloping surface 102b at a point spaced a distance 106b from the i ■ : . cylindrical portion 101b.

Further,- by using a thin gasket with a stem having a sloped area and * 0° angle on the taper, the opening of the propellant will be delayed until after the liquid flow path is open. ¾is sloped area actually functions in much the same manner as the previous steps. As actuation of the valve is commenced, the gnskot 15J moves away from the point IO7, but does not allow propellant out of the system. On continuing actuation, the gasket will finally move away from point 108 and release propellant. This release of propellant actually occurs after the gasket has bent in a reverse angle to that which it holds while the system is at rest. Further, with a 0° angle on the taper 102b and the sloped area 103b , the gasket imbeds itself in the critical portion of the surface 103b more securely, thereby resulting in a tighter seal. This imbedding is assisted by the gasket sliding downward on a ^0° angle of the taper 102b and unward on the surface 103b moving into the critical sealing portion of the stem.

In injection molding, the angle at point 109 is very difficult to fill with plastic material if the angle- at point 110 is sharper than ½0°. If point 109 does not fill out properly, the configuration of the propellant holes 105b will be irregular. With a 0° angle on the taper 102b of the stem, angle 109 is sufficiently large to easily fill out with pl-astic material during molding, thereby resulting in more uniformly shaped propellant holes.

If the angle of the tapered portion 102b of the stem is too great (for example over 70° ) , the gasket will have difficulty finding the slotted portion during assembly. At 0° assembly is achieved easily and the gasket moves into the slotted portion positively. ¾e inner diaphragm will move into the slotted portion easier with a stem having . the sloped surface 103b rather than the steps.

A further advantage of using sloped surfaces 103b is that the propellant filling is made easier because of the aerodynamic curve the propellant follows. With the stops, the propellant has a tendency to bank or deflect off the second stop and move upwards before continuing on its eventual downward path. This reduces propellant ' filling efficiency. 31897/2

Claims (1)

1. CLAIMS plug valve assembly for dispensers of fluid adapted to be attached to a product container for containing the fluid product to be dispensed and adapted to accommodate a pellant in a separate cartridge within the produot said plug valve assembly comprising a valve a pushbutton actuator on the upper end of said stem and having a nozzle therein communicating with said hollow a cap member ted to fit over a product container and having an aperture therein through which the hollow stem is movable against the pressure of a resilient a support secured to the under side of said cap and having a hollow central portion through which said hollow stem is a dip tube secured in said support and opening into said hollow a fluid product flow path through said stem ly of the hollow thereof from a point adjacent said hollow a flexible gasket in said assembly through which said hollow stem passes obturating said fluid product flow path between said product flow path and said hollow interior in the dispersing position of the valve said support having a downwardly open recess a high pressure flexible annular gasket in the bottom of said recess through which said hollow stem retaining ring means retaining said flexible gasket in the bottom of said recess and adapted to be connected to the propellant said stem having a lower cylindrical tion and said support having a bore therethrough between said hollow interior and said downwardly open recess in which said cylindrical portion is in sliding bearing said stem further having a neck portion in the lower end of said cylindrical which 14 neck portion comprises a reduced diameter cylindrical portion upper end is disposed below the bottom of the hollow of the a conically tapered portion joining the upper end of said reduced diameter cylindrical portion to said cylindrical portion and a downwardly and outwardly inclined portion Joining the lower end of said reduced diameter cylindrical portion to the bottom portion of said said stem having downwardly extending passages therein from the hollow of stem to said neck said passages extending substantially parallel to axis of the and ing out of the said neck portion in the region of the conically tapered at least a part of opening being in the cally tapered the thickness of said flexible annular gasket and the vertical dimension of said reduced diameter cylindrical portion being so dimensioned as to cause said high press ure in the position of the to bent inwardly into said recess of eaid support and to be into sealing engagement with eaid downwardly and outwardly portion with conically tapered portion at points spaced from the openings of said passages in neck portion of the A plug assembly as claimed in Claim 1 in which said downwardly extending passages end in in the of said reduced diameter cylindrical plug valve assembly as claimed in Claim 1 in which said downwardly extending passages extend to said conically tapered portion and open out of said tapered A plug valve assembly as claimed in Claim in which said passages open out of said conically tapered portion immediately 15 plug valve assembly as claimed in Claim 3 in which passages open out of said conically tapered portion at a point spaced from said reduced diameter cylindrical A plug valve assembly as claimed in any preceding claim which said downwardly and outwardly inclined portion A plug valve assembly as claimed in any of Claims 1 to 5 in which said downwardly and outwardly inclined portion is lug valve assembly as claimed in any of Claims 1 to 5 or 7 in which said downwardly and outwardly inclined portion is smooth and said tapered portion is tapered at an angle of from to to the A plug valve assembly claimed in Claim 8 in which tapered portion is tapered at an angle of about 40 A plug valve assembly as claimed in any of the preceding claims wherein said recess is flared outwardly and the end of said retaining ring engaged withraid flexible gasket is beveled inwardly and said high pressure flexible gasket extending inwardly and upwardly into engagement with aid neck portion of the stem the stem is in the ing whereby the material of said gasket is compressed furth when the neck portion moves past the as the stem is being depressed to improve the sealing action and delay the opening of said A plug valve assembly substantially as herein described with reference to and as shown in Figures 1 to 7 of the accompanyin A plug valve assembly substantially as herein described with reference as shown in Figures 8 and 9 of the a ccompanying drawings For the Applicants PARTNERS insufficientOCRQuality