US3904124A

US3904124A - Pressurized product dispenser

Info

Publication number: US3904124A
Application number: US496282A
Authority: US
Inventors: Roger P Caron; Chester Luke
Original assignee: Arthur D Little Inc
Current assignee: Arthur D Little Inc
Priority date: 1973-10-31
Filing date: 1974-08-08
Publication date: 1975-09-09
Anticipated expiration: 1992-09-09

Abstract

A dispenser for dispensing liquid product in fine droplet form in compressed air. The dispenser has an air compressing piston cylinder means mounted on the body including a fixed member and a movable member movable relative to the fixed member through a compression stroke to compress the air, and has a valve member normally obturating a compressed air flow path to a nozzle which is opened by actuating pin means operatively associated with the movable member of the air compressing piston cylinder means and the valve member near the end of the compression stroke only when the air compressing piston cylinder means has compressed air to a predetermined pressure. A product container means for a liquid product forms part of the dispenser and a product pressurizing piston cylinder means is provided for pressurizing the product. The movable member of the product pressurizing piston cylinder means is coupled to the valve member for movement substantially simultaneously with the movement of the valve member by the actuating pin means for pressurizing the product. Product valve means is provided in the product flow path between the product pressurizing piston cylinder means and the nozzle means and which is opened at substantially the same time as the product pressurizing piston cylinder means pressurizes the product.

Description

United States Patent (1 1 Caron et al.

[ Sept. 9, 1975 PRESSURIZED PRODUCT DISPENSER [75] Inventors: Roger P. Caron, North Andover,

Mass; Chester Luke, Bolton Conn [73] Assignee: Arthur D. Little, Inc., Cambridge,

Mass.

[22] Filed: Aug. 8, 1974 [2|] Appl. No.: 496,282

Related US. Application Data [63] Continuation of Scr No. 4] [,267, Oct. 31 I973,

Primary E.rurm'nerLloyd Lv King Attorney AgenL or FirmWenderoth, Lind & Ponack [57 ABSTRACT A dispenser for dispensing liquid product in fine droplet form in compressed air. The dispenser has an air compressing piston cylinder means mounted on the body including a fixed member and a movable member movable relative to the fixed member through a compression stroke to compress the air, and has a valve member normally obturating a compressed air flow path to a nozzle which is opened by actuating pin means operatively associated with the movable mem ber of the air compressing piston cylinder means and the valve member near the end of the compression stroke only when the air compressing piston cylinder means has compressed air to a predetermined pressure. A product container means for a liquid product forms part of the dispenser and a product pressurizing piston cylinder means is provided for pressurizing the product. The movable member of the product pressurizing piston cylinder means is coupled to the valve member for movement substantially simultaneously with the movement of the valve member by the actu ating pin means for pressurizing the product. Product valve means is provided in the product flow path between the product pressurizing piston cylinder means and the nozzle means and which is opened at substantially the same time as the product pressurizing piston cylinder means pressurizes the product 18 Claims, [5 Drawing Figures l i A 27 T 29 PATENTEU 1975 snmunf FIG.7

PATENTED SEP 9 i975 sum 6 u? g FIGI4 FIG.I3

PRESSURIZED PRODUCT DISPENSER This is a continuation of application Ser. No. 41 1,267, filed Oct. 3|, 1973, now abandoned.

This invention relates to dispensers of fluid in a spray form, and more particularly to dispensers which a fluid, usually a liquid, is dispensed by means of a high pressure stream of air.

BACKGROUND AND PRIOR ART For many years, most of the aerosol dispensers have been the type in which a propellant is compressed in a valved container along with the product to be dispensed, so that when the valve is opened, the pressure of the propellant forces the product, mixed with the propellant, through the valve and out through a nozzle means, and because of the high pressure of the propellant, the mixed product and propellant emerge from the nozzle in spray form.

In the last few years, there has been developed a type of aerosol dispenser in which the propellant is stored in the dispensing apparatus separately from the product to be dispensed, the propellant and product being mixed only upon being actually dispensed. This has enabled the dispensing by means of aerosol dispensers, of products which are normally incompatible with the propellants being used when the two are stored together for any length of time. However, this type of dispenser still utilizes a propellant as the means for dispensing and atomizing the product.

There has recently been much discussion about the possible damaging effects of the propellants commonly used in such aerosol dispensers, such as freon gas. Where the products are not used on the human body, such as with paint or insecticide, precautions can be taken by the user so that he does not inhale the dispensed mixture of product and propellant. However, where the product is to be used on the human body or to be ingested into the human body, such as in the case of deodorant which is used directly on the body, or a breath freshener which is sprayed directly into the mouth, there is no way to avoid exposing the user to the damaging ettects of the propellant.

This drawback in the aerosol dispensers has lead to the recent development of dispensers which use a charge of compressed air to aspirate a product from a separate product container each time the dispenser is actuated. Examples of such dispensers are found in the US. Pat. Nos. 3,672,545 and 3,733,010. In these dispensers, since there is no propellant used, but only compressed air, there is no danger to the user from the propellant. These devices therefore have a great potential for use in dispensing such products as medicaments, cosmetic and personal hygiene products and the like where it is desirable that the user not be exposed to the dangers of conventional propellants.

It has now been found, however, that it is not possible to obtain a very fine droplet size in such a device where the compressed air is used to aspirate the liquid product from a container. While droplet size is not important for such things as breath fresheners or deodorants, it is extremely important for medicaments which it is desired will be drawn into the bronchial regions or the lungs in the respiratory system. For example, for medicuments for use in treating asthma, it is desirable that the droplet size be as fine as l-lU microns.

OBJECTS OF THE INVENTION It is an object of the present invention to provide an aerosol type dispenser which uses compressed air as the propellant and which can dispense an atomized liquid with an extremely fine droplet size.

It is a further object of the present invention to pro duce such a dispenser which can compress the air used for dispensing the produce with a force such that the operation of the device is easy for a user.

It is a still further object of the invention to produce such a dispenser which has few moving parts and which is easy and inexpensive to make and which will be reliable in operation.

BRIEF SUMMARY OF THE INVENTION These objects are achieved by an aerosol dispenser which has a liquid product container, a piston cylinder arrangement for creating a charge of air under pressure, and valve means for controlling the flow of liquid product from the product dispenser and air from the piston-cylinder arrangement to a dispensing nozzle. The valve means for releasing the air from the pistoncylinder arrangement is also coupled to a piston means which exerts pressure on the liquid product to be dispensed as it is allowed to flow to the nozzle. Thus, there is a mixing of air under pressure and a liquid product under pressure at the dispensing nozzle, and those two media together are ejected from the nozzle in a spray having droplets less than the upper limit of the desired size.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in connection with the accompanying drawings, in which:

FIG. 1 is a sectional elevational view of a first embodiment of the aerosol dispenser according to the present invention with the parts in the rest positions;

FIG. 2 is a view similar to FIG. I with the parts in the dispensing positions;

FIG. 3 is a perspective view of the device on a smaller scale;

FIG. 4 is a sectional elevation view of a second embodiment of the dispenser according to the invention with the parts in the rest positions;

FIG. 5 is a view similar to FIG. 4 with the parts in the dispensing positions;

FIG. 6 is a sectional elevation view of a third embodiment of the dispenser according to the invention with the parts in the rest positions;

FIG. 7 is a view similar to FIG. 6 with the parts in the dispensing positions;

FIG. 8 is a partial sectional elevation view of a modified form of nozzle arrangement;

FIG. 9 is a partial sectional elevation view ofa further modified form of nozzle arrangement;

FIG. 10 is a sectional elevation view of a fourth embodiment of the dispenser according to the invention with the parts in the rest positions;

FIG. 11 is a view similar to FIG. 10 with the parts in the dispensing positions;

FIG. 12 is partial sectional elevation view of a modified product piston-cylinder arrangement for the embodiment of FIGS. IO and 1];

FIG. 13 is a sectional elevation view of a fifth embodiment of the dispenser according to the invention with the parts in the rest positions;

FIG. 14 is a view similar to FIG. [3 with the parts in the dispensing positions; and

FIG. 15 is a perspective view of the device of FIGS. 13 and 14 on a smaller scale.

DETAILED DESCRIPTION OI THE DRAWINGS In the embodiment shown in FIGS. 1-3, the dispenser is comprised of a dispenser body and mounted on one of the dispenser body is a product container means 21 for containing liquid product. In this embodiment the product container means 21 is mounted on one end of the dispenser body 20 for a purpose which will be described hereinafter. The product container means 21 has a container 22 in the mouth of which is secured a container closure 23 having a product dispensing aperture 23a therein. In this embodiment there is sealed between the container mouth and the closure 23 and depending into the container 22 a flexible bag 24 for containing the product to be dispensed. An aperture (not shown) is provided in the container for admitting air thereto, so that as the product is removed from the bag 24 as it is dispensed, air enters the container means 21 and the bag collapses. This avoids buildup of a vacuum in the product container means 21. If the bag 24 or some such means is not used, a provision should be made for relieving the vacuum in the product container means 21 to avoid buildup of the vacuum therein.

Also mounted on the dispenser body 20 is a gas compressing piston cylinder means 25. In this embodiment the piston cylinder means is mounted on the other end of the dispenser body 20 from the product container means 21 so that when pressure is exerted on the piston cylinder means 25 to compress gas, this pressure can be counterbalanced by pressure exerted on the product container means 21 in a manner to be described hereinafter. The piston cylinder means 25 is comprised of a cylinder 26 which is integrally formed with the dispenser body 20 and having a bore 260 therein in which is slidable a piston 27. A piston sleeve 28 on the outer end of the piston 27 extends down along the sides of the cylinder 26 in a slidable fit therewith to guide the piston in its movement along the cylinder 26, and has a slot 280 therein alighed with nozzle means, described later, so that the nozzle means is never covered by the sleeve 28. Between the end of the sleeve 27 and a recess in the cylinder 26 is a piston return spring 29 which normally urges the piston 27 out of the cylinder 26. On the inner end of the piston 27 is a piston seal 27a which is of the type which has a lip 27b extending at an angle therefrom in a direction radially outwardly of the piston and axially inwardly of the cylinder so that it wipes along the cylinder wall in tight engagement therewith to seal the cylinder during the compression stroke of the piston. and so that it can move frely away from the cylinder wall during the outward movement of the piston to allow air to pass the piston and the seal to relieve the vacuum that would otherwise build up in the cylinder during the withdrawal of the piston therefrom.

A reverse arrangement of parts could also be used, i.e., the dispenser body could have a fixed piston thereon and the cylinder could be a sleeve slidable on the fixed piston.

Extending upwardly from the inner end of the piston 27 is an actuating pin 30 which when the piston 27 is at its innermost position in the cylinder 26 extends into a compressed air passage 31 in the dispenser body 20. The air passage 31 opens into a dispenser body bore 32 within the dispenser body 20. A compressed air control valve 33 within bore 32 is positioned over the end of the compressed air passage 31 to close it. When the piston 27 reaches its innermost position in the cylinder 26, the pin 30 lifts the valve 33 from its seat around the end of the air passage 31 to open the air passage. It will of course be understood that the pin 30 can also be placed on the valve 33 and project downwardly in the Figures through the air passage 31 and into the cylinder 26 so as to be engaged by the piston 27 at its innermost position in the cylinder 26. Thus what is essential is that the actuating pin 30 be operatively associated with the piston 27 and the valve 33 to open the valve at the innermost end of the stroke of the piston 27.

Opening laterally out of the dispenser body bore 32 is a dispensing nozzle means generally indicated at 34 and which in this embodiment comprises a small bore 35 extending out of the bore 32 and a divergent passage 36 extending out of the bore 32 and a divergent passage 36 extending from the end of the small bore 35 to the periphery of the dispenser body 20.

Slidably positioned within the dispenser body bore 32 is a product pressurizing piston 37 having a piston ring 38 therearound in sealing engagement with the inner wall of the bore 32. The product pressurizing piston 37 has an extension 39 which extends downwardly therefrom into engagement with the valve 33. In this em bodiment the end of the extension 39 has a recess therein in which the valve 33 is positioned. The extension 39 is smaller in diameter than the bore 32 so that a space is provided around the extension 39 which constitutes an extension of the compressed air passage 31 from the valve 33 to the dispensing nozzle means 34. In the present embodiment, the exterior of the extension 39 has grooves 40 therein, the lands between the grooves serving to guide the extension 39 in its movement along the bore 32. The product pressurizing piston 37 also has a pressurized product bore 41 therethrough opening laterally of the piston 37 into a diverged groove 42 therearound, and valve means is provided for the pressurized product bore in the form of a ring gasket 43 seated in the bottom of the groove 42. A product pressurizing piston return spring 44 is positioned in the bore 32 above the piston 37. Spring 44 is sufficiently strong to hold valve 33 seated against the pressure of air built up in the cylinder 26 until the actuating pin 30 opens the valve 33. At its upper end the spring 44 presses against an apertured check valve retainer 45 which retains a ball check valve 46 in a recess in a check valve body 47. Projecting from the check valve body 47 through a seal 48 in a recess in the container closure 23 is a product conduit 470 having a passage 47b therethrough.

With the parts in the rest positions as shown in FIG. 1, liquid product from the product container means 21 will have flowed past the check valve 46 and filled the space in the dispenser body bore 32 above the product pressurizing piston 37, which space will hereinafter be referred to as the product pressurizing space. However, the ring gasket 43 around the groove 42 will prevent product from flowing out of the product pressurizing space.

The dispenser is held between the thumb and a forefinger of the hand and the product container means 2| and the piston 27 are urged toward each other by a squeezing action. Air pressure is built up in the cylinder 26 until the actuating pin 30 opens the compressed air control valve 33. At this point compressed air is suddenly released from the cylinder 26 to flow through the air passage 3] and the extension thereof past the extension 39 to the nozzle means 34. At the same time the actuating pin 30 lifts the valve 33, it urges the extension 39 upwardly and hence urges the product pressurizing piston 37 upwardly against the action of return spring 44. The liquid product in the product pressurizing space will thus be pressurized, and will exert pressure through the pressurized product bore 41 on the ring gasket 43 to stretch the ring gasket and allow pressurized product to flow past the ring gasket to the nozzle means 34. The pressurized product and the compressed air will thus be mixed just at the entrance to the small bore 35 and will be dispensed as a mixture of fine liquid droplets in compressed air from the divergent passage 36.

The apparatus will dispense only a small amount of liquid product for each actuation as described above, because as soon as sufficient liquid product has flowed out of the product pressurizing space, the pressure of the liquid product will drop, regardless of whether the finger pressure is maintained or not. When the liquid pressure drops sufficiently, the ring gasket 43 closes, preventing further flow of liquid product. Even if the supply of compressed air is not exhausted, no further product will flow, but rather only compressed air will flow until the air in the cylinder 26 and passage 31 fails sufficiently low that spring 44 urges the product pres surizing piston 37 down to close the valve 33. A reduced pressure will thus be created in the product pressurizing space which will open the check valve 46 to cause product to flow out of product container means 21.

An empty product container means 21 can be removed and replaced by removing it from the conduct 47a and fitting a full product container means over the conduct 470.

There has thus been provided a dispensing apparatus which uses only compressed air for dispensing the product yet which also puts the product itself under pressure for mixing it with the compressed air. This makes it possible to atomize the liquid into smaller droplets than in a device in which the compressed air is used to aspirate the product from a product supply. This structure is such, however, that only a small dose is dispensed at each actuation, so that the device can be safely used to dispense medicaments in predetermined doses and the user can not obtain more than the prescribed dose without actuating the device several times. The sizes of the nozzle bores, passages and pistons and cylinders and the strengths of the springs and the gaskets can be designed to provide the desired droplet size and to make sure that air is flowing before the product is released and that air continues to flow after the product flow is shut off so that the nozzle is purged of product.

A number of variations are possible in the structure described in the foregoing, and some of them will be described in connection with the further embodiments. In the following description, only those parts of the further embodiments which differ from the above described embodiment and the differences in operation produced thereby will be described.

The dispenser of the present invention can be modified to utilize the sole invention of Roger P. Caron as disclosed and claimed in an application filed on even date herewith and entitled Nozzle Means For Produc ing Fine Droplets", application Ser. No. 41 1,268, filed Oct. 3 l, 1973. This modified form of the present invention is shown in FIGS. 4 and 5. The nozzle means 54 comprises the small constricted bore 55 and the divergent passage 56, but these are contained in a nozzle insert 53 which is fitted tightly into a lateral recess 52 in the dispenser body 20. Defined between the inner end of the nozzle insert 53 and the inner end of the recess 52 is a part 5] of the compressed air flow path which leads laterally into the small bore 55 of the nozzle means. Extending through the dispenser body 20 from the bottom of the recess 52 is a compressed air bore 50 which opens into the bottom part 32a of the dispenser body bore. Within the bottom part 32a is the valve member 33 which is mounted in the extension 39 of the product pressurizing piston. A valve seat 33a is provided in the dispenser body 30 for the valve member 33 to seat on.

The extension 39 has a smaller diameter part extending upwardly through a small diameter part 32b of the dispenser body bore, and in the upper larger diameter part 320 of the dispenser body bore is positioned the product pressurizing piston 57. Mounted in the bottom of the piston 57 is a valve member 63 which seats over the upper end of the portion 32b of the dispenser body bore to seal it off when the valve member 57 is seated. Grooves 61 are provided in the sides of the piston 57. Return spring 44 urges the piston 57 and the valve member 63 downwardly, and as in the first embodiment the spring must be strong enough to hold both the valve 33 and the valve 63 seated against the force of the compressed air in the cylinder 26. A groove 62 extends along the dispenser bore portion 32b to the location of a lateral passage 64 extending to the bottom of the nozzle insert recess 52. The grooves 61, the groove 62 and passage 64 together form a product flow path valved ty the valve 63. The check valve body 47 extends downwardly into the upper end of the dispenser body bore portion 32c and is retained therein by a ring 47c and is sealed by a gasket 47f.

The operation of this embodiment differs from that of the first embodiment in the way the pressurized product is valved and in the way in which the air and product flow through the nozzle means. When the valve 33 is raised by the actuating pin 30, compressed air will flow through the passage 31, the grooves 40, passage 50 and passage 51. At the same time the valve 33 is raised, the valve 63 will be raised by the upward movement of the extension 39. This positively opens the flow path for the pressurized product which can then flow along the

grooves

61 and 62 and through the passage 64 to the nozzle means 54. It will be seen that the flow of the product is more or less linear through the nozzle means while the air is fed substantially transversely into the product stream. At the same time the product pressurizing piston 57 is raised against the action of spring 44 to place the product in the bore portion 320 under pressure. Otherwise the action of the apparatus is the same as for the embodiment of FIGS. l-3.

The embodiment of FIGS. 6 and 7 differs from that of FIGS. l3 in that a different nozzle means 74 is used like that of FIGS. 4 and 5, and the valving of the product flow path is somewhat different. The nozzle means 74 comprises the small bore 75 and the divergent passage 76, but these are contained in a nozzle insert 73 which is fitted tightly into a lateral recess 72 in the dispenser body 20. Defined between the inner end of the nozzle insert 73 and the inner end of the recess 72 is a part 71 of the compressed air flow path which leads to the small bore 75. Extending through the dispenser body 20 from the bottom of the recess 72 is a compressed air bore 70 which opens into the bottom part 32d of the dispenser body bore. Within the bottom part 32d is the valve member 33 which is mounted in the ex tension 79 of the product pressurizing piston 77. Grooves 70a in the extension 79 permit passage of air from the air passage 31 to the air bore 70.

The product pressurizing piston 77 is relatively loosely fitted in bore portion 32d to leave space 81 and has a piston ring 78 sealing the piston and the bore portion 32d, and has an inverted V-cross-section seal 83 near the upper end thereof. This seal is such that when the pressure of liquid in the space between the piston 77 and the wall of the bore 37d reaches a certain point it will collapse and pass the liquid. Opening into the bore portion 37d is a lateral passage 84 which extends to the bottom of the nozzle insert recess 72. The check valve body 47 extends downwardly into the upper end 32c of the dispenser body bore and is secured therein in liquid tight fashion.

The operation of this embodiment differs from that of the embodiment of FIGS. 4 and only in the way the pressurized product is valved. When the valve 33 is raised by the actuating pin 30, compressed air will flow through the passage 31, the grooves 70a, the passage 70 and passage 71. At the same time the valve 33 is raised, the product pressurizing piston 77 will be raised against the force of spring 44 to pressurize product in the space in the dispenser body bore portion 322. Pressurized liquid will then flow through the space 81 between the piston 77 and the bore portion 32d and will cause the seal 83 to collapse, so that the pressurized product can flow out through the lateral passage 84 to the nozzle means 74. The seal 83 acts as valve means in the product flow path formed by the space 81 and the passage 84.

In the embodiments described thus far. the compressed air and the product have been delivered simul taneously to a space just ahead of the small bore of the nozzle means or the air has been fed substantially transversely into a stream of product in the nozzle means. However, other ways of bringing them together are possible. For example, as shown in FIG. 8, which is a modified form of the structure of FIGS. 6 and 7, the nozzle insert 90 has a converging passage 91 which opens into the dispenser body bore 32, which passage leads to a venturi passage 92 which in turn opens into a slightly larger passage 93, and the latter passage opens into an outwardly facing concave recess 94. Opening into the slightly larger passage 93 are radial passages 95, and around the outer ends of the passages 95 is an annular product supply chamber 96 into which the product passage 97 from the dispenser body bore opens. In this arrangement the pressurized product is fed into the stream of compressed air flowing through the venturi passage 92.

As shown in FIG. 9. the compressed air and pressurized product need not be mixed until after they have been ejected from the nozzle means. The nozzle insert 100 has only a divergent passage I06 therein. The dispenser body has a projection a projecting into the nozzle insert recess 102, through which projection the pressurized product passage 104 opens from the dispenser body bore 32. An annular space 101 is left between the bottom of the nozzle insert recess 102 and the nozzle insert and from this recess a groove 102a leads along the projection 20a and opens into the divergent passage 106. Compressed air bore opens into annular space 101 in the bottom of the nozzle insert recess 102 from the dispenser body bore 32. In this arrangement, the pressurized product is fed substantially axially out of the divergent passage 106 and the compressed air is fed along a path substantially parallel thereto and they mix in the divergent passage.

In all of the embodiments thus far, the product pressurizing has been accomplished by means of a piston which is moved upwardly in the dispenser body bore serving as a cylinder by means of the actuating pin on the air compressing piston. However, the pressurizing of the liquid product can be carried out by a reverse arrangement of parts, i.e., a fixed piston and a movable cylinder. Such an arrangement is shown in FIGS. 10 and 11 in which the dispenser body has the movable cylinder therein as part of a piston cylinder means for pressurizing the liquid product.

In FIGS. 10 and 11, the dispenser body has a dispenser body bore 132 therein. With the dispenser body bore 132 is slidably mounted a cylinder means which has two parts. An outer part 147a has the nozzle means 34 with the small bore 35 and the divergent passage 36 projecting laterally therefrom, and has a bore l47c therein into which the small bore 35 opens. The portion 147a is slidably mounted in the dispenser body bore 132 and is sealed therein by seal 151. Fixed within the outer part 1470 by means ofa key 148 is an inner part 147!) having an upwardly open cylinder recess 147d therein. Around the outside of the inner part [47b and positioned opposite the small bore 35 is a divergent groove 142, and opening into the groove from the cylinder recess 147d is a pressurized product bore 141. A ring gasket 143 closes off the bore 141. An extension 139 extends downwardly from the bottom of the inner part 147b, and has the valve member 33 mounted in the bottom thereof. A groove 140 extends along the bore 1470 from the bottom of the outer part 1470 to the small bore 35. A piston member 137 which is here shown as integral with the container closure 23 extends into the cylinder recess 147d and a gasket 138 seals the cylinder 147d and the piston member 137. The piston has a product supply passage 137a therethrough from the check valve 47 to the lower end of the piston member 137. Return spring 144 is positioned between the upper end of the outer body portion 147a and the container closure 23.

In operation, when the actuating pin 30 raises the valve 33, compressed air will flow past the valve 33 and along the groove 140 to the nozzle means 34. At the same time, the cylinder means constituted by the outer portion 147a and the inner portion 147b secured thereto by the key 148 is raised upwardly, sliding in the bore 132. Since the piston 137 is fixed by virture of the container closure being fixed relative to the upper end of the dispenser body 20, the cylinder means moves upwardly around the piston 137, thus pressurizing liquid product in the cylinder recess 147d. The pressurized product forces the ring gasket 143 off its seat to allow the liquid product to mix with the compressed air at the entrance to the small bore 35.

The modification of FIG. 12 differs from that of FIG. 11 in that the small bore 35 and the divergent passage 36 are formed in the dispenser body 120 rather than in the cylinder means, so that the cylinder means can be a single member 177. The structure and operation are otherwise the same as in FIGS. and 11.

In all of the embodiments disclosed thus far, the product container has been on one end of the device and the piston cylinder means for compressing air has been on the other end, so that the device is grasped between the thumb and fingers with one on the product container and the other on the piston cylinder means for compressing the air. It is also possible to make an arrangement where both the product container and the piston cylinder means for compressing the air are on the same end of the device. Such an embodiment is shown in FIGS. 13-15.

The dispenser body 220 has the air compression piston cylinder means on one end thereof, comprised of the cylinder 226, the sleeve 228 and the return spring 229. The piston 227 is slidably mounted within the cylinder bores 226a and has the piston 227a thereon in the same manner as in FIGS. 1-3. The dispenser body 220 has the nozzle means 34 therein with the small bore 35 and divergent passage 36. The small bore opens into dispenser body bore 232, and into the bottom of the bore 232 opens the air passage 231 from the inner end of the cylinder bore 226a. Valve member 233 seats over the air passage 231, and is mounted in member 239a which is slidable in bore 232 and is sealed relative thereto by seal 239d. A cb sure member 232a having an aperture 232b therein closes the upper end of bore 232, and a return spring 244b is positioned between the closure member 2320 and the member 239a.

The product container means is positioned on the piston 227, the container closure 223 being mounted on the piston 227 and having the container 222 and bag 224 attached thereto and extending outwardly from the piston along the cylinder bore 2260. The sleeve 228 is attached to the outer end of the container 222, which thus acts as an extension of the piston 227. In this way, space otherwise occupied by solid material of the piston and thus in a sense not fully utilized is used to contain the product container.

Within the piston 227 is contained the piston cylinder means for pressurizing the product and the means for valving the pressurized product flow path to the nozzle means. Piston 227 has a bore therein in which is slidably mounted a product pressurizing piston 237 which is urged upwardly in the figure by a return spring 244a, the other end of which engages a product check valve 246 which controls flow of product through a product conduit 247 which extends through a seal 248 in the container closure 223. An actuating member 230 is positioned in the upper end of the bore and extends upwardly through the piston seal 227a in the manner of the actuating pin of the previously described embodiments. The member is hollow and has a ball valve 243 in the upper end thereof which is held in place by an extension 237a on the piston 237. An extension 230a on the valve member 233 projects downwardly therefrom.

In operation, when the device is gripped between the thumb and fingers and squeezed, the piston 227 is forced into the cylinder 226 to compress the air therein until the actuating member 230 reaches the extension 2300 on the valve 233. At this point, the force of the spring 244!) is holding the valve 233 closed against the pressure of the air building up in the cylinder bore 226a. When the extension 230 engages the ball valve 243, the valve member is raised, the spring 2440 being stiffer than spring 244)). However, member 239b soon reaches the closure member 2320, and further movement of the piston 227 forces the actuating member up past the ball valve 243 which is at this point blocked against further movement by the valve 233 and member 239b. The product pressurizing piston is thus blocked while the piston moves up past it, so that pressure is exerted on the product to force it upwardly through the actuating member past the ball valve 243 and into the flow of compressed air to the nozzle means 34.

Release of the pressure causes return of the parts to the position of FIG. 13, the aperture 232b in the closure member 232a permitting air to enter the space above member 239 to avoid the creation of a vacuum therein.

There has thus been provided a dispensing device which meets all of the objects recited, using compressed air as the propellant, and having a structure which will pressurize the liquid product so that when mixed with the compressed air, a fine droplet size is achieved. In actual working models of the device, an average droplet size as fine a 5 microns has been achieved. The size of the device and the strength of the springs are such that it is easy for the user to operate, yet is very safe, dispensing only one dose for each actuation regardless of how long the device is held in the actuated position. The number of parts has been kept to a minimum, and they can all be made of molded plastic, with the exception of the springs. The device is extremely reliable in operation.

It will be understood that the product container means can be designed to be detachable from the remainder of the device so that the device can be recharged with product and used again and again.

It is thought that the invention and its advantages will be understood from the foregoing description and it is apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing its material advantages, the forms hereinbefore described and illustrated in the drawings being merely preferred embodiments thereof.

What is claimed is:

1. A dispenser for dispensing liquid product in fine droplet form in compressed air, comprising a dispenser body, nozzle means opening out of said dispenser body, an air compressing piston cylinder means mounted on said body and having a fixed member and a movable member movable relative to the fixed member through a compression stroke to compress the air, said body having a compressed air flow path therethrough from said air compressing piston cylinder means to said nozzle means for conducting compressed air from said air compressing piston cylinder means to said nozzle means, a valve member in said body and normally obturating said compressed air flow path, actuating pin means operatively associated with the movable member of said air compressing piston cylinder means and said valve member for positively actuating said valve member to open said compressed air flow path near the end of said compression stroke only when said air compressing piston cylinder means has compressed air to a predetermined pressure, a product contain-tr means for a liquid product forming part of said disper "r zmd having a product flow path therefrom to said nozzle means, a product pressurizing piston cylinder means in said flow path for pressurizing the product and having a piston member and a cylinder member one of which is movable relative to the other for pressurizing the prod uct, the movable member of said product pressurizing piston cylinder means being coupled to said valve member for movement substantially simultaneously with the movement of said valve member by said actu ating pin means for moving said movable member of said product pressurizing piston cylinder means for pressurizing the product, return spring means engaged with said movable member of said product pressurizing piston cylinder means and said valve member for holding said valve member closed until it is positively opened by said actuating pin means, and product valve means in said product flow path between said product pressurizin g piston cylinder means and said nozzle means and which is opened at substantially the same time as said product pressurizing piston cylinder means pressurizes the product.

2. A dispenser as claimed in claim 1 in which said air compressing piston cylinder means and the product container means are on opposite ends of said dispenser body, and said dispenser body has a cylindrical recess therein aligned with said air compressing piston cylinder means and constituting a product pressurizing cylinder and a product pressurizing piston is slidably positioned therein, said valve member engaging the end of said product pressuring piston which is toward said air compressing piston and cylinder means, whereby when said valve member is moved to open said compressed air flow path, said product pressurizing piston is moved in the product pressurizing direction.

3. A dispenser as claimed in claim 2 in which product pressurizing piston has an extension thereon extending toward said air compressing piston cylinder means and having a shape for defining between said extension and the internal surface of said product pressurizing cylinder a portion of the air flow path, the nozzle means opening into said product pressurizing piston adjacent said extension, and said extension having the product flow path extending therethrough from the product pressurizing piston and opening into said product cylinder adjacent the position of said nozzle means.

4. A dispenser as claimed in claim 3 in which said extension has a recess therearound into which the product flow path opens, and said product valve comprising a ring gasket seated in said recess and normally obturating said product flow path and stretchable to open said product flow path when pressurized product flows through said product path.

5. A dispenser as claimed in claim 2 in which said dispenser body has a recess therein between said cylindrical recess and said air compressing piston cylinder means, said body further having a passage between said recess and said cylinder and a further passage between said recess and said air compressing piston cylinder means, said valve member being positioned in said recess and obturating said further passage, said product pressurizing piston having an extension thereon extending through said firstmentioned passage and engaging said valve member, said body having a portion of the air flow path extending therethrough from said recess to said nozzle means, and said product valve means comprising a valve member on said product pressurizing piston and obturating said further passage when said product pressurizing piston is in the rest position and movable away from said further passage when said product pressurizing piston is moved in the product pressurizing direction.

6. A dispenser as claimed in claim 2 further comprising a conduit projecting from said product pressurizing piston cylinder means and opening at one end into said product pressurizing cylinder and at the other end into said product container means, said product container means having an apertured closure closing the end thereof and removably fitted over said conduit, whereby said product container means can be removed from said conduit and replaced.

7. A dispenser as claimed in claim 6 further comprising a check valve means in said conduit.

8. A dispenser as claimed in claim 2 in which said product pressurizing piston has an extension thereon extending toward said air compressing piston cylinder means and having a shape for defining between said extension and the internal surface of said product pressurizing cylinder a portion of the air flow path, the body having air flow passage opening into said product pressurizing cylinder adjacent said extension and extending to said nozzle means, said body having a product flow passage opening into said product pressurizing cylinder at a point spaced along said cylinder from said air flow passage in a direction away from said air compressing piston cylinder means, a sealing gasket between said product pressurizing piston and cylinder at a position between said passages, and a collapsible gasket means between said product flow passage and the remainder of said product pressurizing cylinder which is collapsible under pressure of the product for passing product along said product pressurizing cylinder toward said product passage.

9. A dispenser as claimed in claim 1 in which nozzle means comprises a venturi having a convergingdiverging passage and said product flow path extends to said lateral passages and said compressed air flow path extends to said converging-diverging passage.

10. A dispenser as claimed in claim 1 in which said nozzle means comprises a venturi having a convergingdiverging passage and lateral passages opening thereinto, and said product flow path extends to said converging-diverging passage and said compressed air flow path extends to said lateral passages.

11. A dispenser as claimed in claim 1 in which said nozzle means comprises a constricted passage having a divergent portion at the discharge end thereof, and lateral passages opening into said constricted passage, and said product flow path extends to said lateral passages and said compressed air flow path extends to said constricted passage.

12. A dispenser as claimed in claim I in which said no7zle means comprises a constricted passage having a divergent portion at the discharge end thereof and lateral passages opening into said constricted passage, and said product flow path extends to said constricted passage and said compressed air flow path extends to said lateral passages.

13. A dispenser as claimed in claim 1 in which said nozzle means comprises a constricted passage having a divergent portion at the discharge end thereof and a passage parallel to said constricted passage and opening into said divergent portion adjacent the end of said constricted passage, and said product flow path extends to said constricted passage and said compressed air flow path extends to said parallel passage.

14. A dispenser as claimed in claim 1 in which said air compressing system cylinder means and said product container means are on opposite ends of said dispenser body, and said dispenser body has a bore therein aligned with said air compressing piston cylinder means, a product pressurizing cylinder means slidably mounted in said bore, said valve member engaging the end of said product pressurizing cylinder means which is toward said air compressing piston and cylinder means, a product pressurizing piston fixed on said dispenser body and slidably positioned within said product pressurizing cylinder means and along which said cylinder means is movable, said product pressurizing cylinder means having a product flow path opening out of the interior thereof.

15. A dispenser as claimed in claim 14 in which said product pressurizing means has said nozzle means thereon.

16. A dispenser as claimed in claim 1 in which said air compressing piston cylinder means comprises a cylinder fixed to said dispenser body and an air compressing piston slidably with said piston, said air compressing piston having said product container means as a part thereof, said air compressing piston having a bore therein constituting a product pressurizing cylinder and which communcates with said product container means, a product pressurizing piston slidably positioned in said bore, said piston having a hollow extension thereon extending through said air compressing piston and engaging said valve member at the end of the compression stroke, said product flow path being through said hollow extension, said extension also constituting said actuating pin.

17. A dispenser as claimed in claim 6 further comprising a spring loaded check valve in said hollow extension and a pin on said valve member for engaging said check valve at the end of the compression stroke of the air compression piston for opening said check valve, and stop means on the opposite side of said valve member from said air compressing cylinder for stopping said valve member after a limited amount of movement, whereby said check valve is opened after the opening of said valve member and the pressurized product starts to flow only after compressed air starts to flow,

18. A dispenser for dispensing liquid product in fine droplet form in compressed air, comprising a dispenser body, nozzle means opening out of said dispenser body, an air compressing piston cylinder means mounted on said body and having a fixed member and a movable member movable relative to the fixed member through a compression stroke to compress the air, said body having a compressed air flow path therethrough from said compressing piston cylinder means to said nozzle means for conducting compressed air from said air compressing piston cylinder means to said nozzle means, a valve member in said body and normally obturating said compressed air flow path, actuating pin means operatively associated with the movable member of said air compressing piston cylinder means and said valve member for positively actuating said valve member to open said compressed air flow path near the end of said compressing stroke only when said air compressing piston cylinder means has compressed air to a predetermined pressure, a product container means for a liquid product forming part of said dispenser and having a product flow path therefrom to said nozzle means, a product pressuring means in said flow path for pressuring the product and having a movable member movable relative to to the dispenser body for pressurizing the product, the movable member of said product pressurizing means being coupled to said valve member for movement substantially simultaneously with the movement of said valve member by said actuating pin means for moving said movable member of said product pressurizing means for pressurizing the product, and return bias means engaged with said movable member of said product pressurizing means and said valve member for holding said valve member closed until it is positively opened by said actuating pin means.

Claims

1. A dispenser for dispensing liquid product in fine droplet form in compressed air, comprising a dispenser body, nozzle means opening out of said dispenser body, an air compressing piston cylinder means mounted on said body and having a fixed member and a movable member movable relative to the fixed member through a compression stroke to compress the air, said body having a compressed air flow path therethrough from said air compressing piston cylinder means to said nozzle means for conducting compressed air from said air compreSsing piston cylinder means to said nozzle means, a valve member in said body and normally obturating said compressed air flow path, actuating pin means operatively associated with the movable member of said air compressing piston cylinder means and said valve member for positively actuating said valve member to open said compressed air flow path near the end of said compression stroke only when said air compressing piston cylinder means has compressed air to a predetermined pressure, a product container means for a liquid product forming part of said dispenser and having a product flow path therefrom to said nozzle means, a product pressurizing piston cylinder means in said flow path for pressurizing the product and having a piston member and a cylinder member one of which is movable relative to the other for pressurizing the product, the movable member of said product pressurizing piston cylinder means being coupled to said valve member for movement substantially simultaneously with the movement of said valve member by said actuating pin means for moving said movable member of said product pressurizing piston cylinder means for pressurizing the product, return spring means engaged with said movable member of said product pressurizing piston cylinder means and said valve member for holding said valve member closed until it is positively opened by said actuating pin means, and product valve means in said product flow path between said product pressurizing piston cylinder means and said nozzle means and which is opened at substantially the same time as said product pressurizing piston cylinder means pressurizes the product.

9. A dispenser as claimed in claim 1 in which nozzle means comprises a venturi having a converging-diverging passage and said product flow path extends to said lateral passages and said compressed air flow path extends to said converging-diverging passage.

10. A dispenser as claimed in claim 1 in which said nozzle means comprises a venturi having a converging-diverging passage and lateral passages opening thereinto, and said product flow path extends to said converging-diverging passage and said compressed air flow path extends to said lateral passages.

12. A dispenser as claimed in claim 1 in which said nozzle means comprises a constricted passage having a divergent portion at the discharge end thereof and lateral passages opening into said constricted passage, and said product flow path extends to said constricted passage and said compressed air flow path extends to said lateral passages.

17. A dispenser as claimed in claim 6 further comprising a spring loaded check valve in said hollow extension and a pin on said valve member for engaging said check valve at the end of the compression stroke of the air compression piston for opening said check valve, and stop means on the opposite side of said valve member from said air compressing cylinder for stopping said valve member after a limited amount of movement, whereby said check valve is opened after the opening of said valve member and the pressurized product starts to flow only after compressed air starts to flow.