Liquid spray system

Abstract

A spray system for dispensing a homogenous mixture of a liquid formulation and propellant as an atomized aerosol where a fill cup containing a liquid base is connected to a charge can to pressurize the inside of the fill cup and to act as a propellant. The charge can is attached to the fill cup through a fitting in fluid communication with the interior of the fill cup, where the fitting may be configured to allow the pressurized charge can to be detached after adding a propellant compatible with the liquid base to the fill cup. Preferably the liquid formulation is a paint base that can be tinted at the point of sale before charging with the charge can.

Claims

1. A spray system for liquids comprising, in combination, a nozzle; a valve assembly comprising a dip tube that is in fluid communication with the nozzle, where the valve assembly has a crimpable connector located below the nozzle; a cap comprising a top opening configured for accepting the crimpable connector to form a crimped sealed connection, where the cap has lower opening opposite the top opening; a disposable container comprising an upper end configured for removable connection to the lower opening, where the disposable container has a lower end and an interior cavity, where the lower end has an inlet fitting that is in fluid communication with the interior cavity and where the disposable container is constructed of a material such that the interior cavity can withstand an internal pressure greater than 0 psig when the upper end connected to and is sealed to the lower opening of the cap; a seal positioned between the lower opening and the upper end such that when the cap is releasably connected to the disposable container a pressure seal is created between the disposable container and the cap; and a charge can comprising an inside portion that is pressurized with a propellant to greater than atmospheric pressure when in a first disconnected state, where the charge can further comprises an outlet fitting that is configured to cooperate and engage with the inlet fitting when in a second connected state such that the pressurized propellant will flow from the charge can into the interior cavity of the disposable container, wherein the inlet fitting further comprises a check valve and metal screw threads that are engaged with the outlet fitting when the charge can is in the second connected state such that a hand support is formed for a user of the spray system when operating the spray system.

2. The spray system of claim 1, wherein the inlet fitting and the outlet fitting form a permanent and non-removable connection when the charge can is in the second connected state.

3. The spray system of claim 1, wherein the lower end of the disposable container comprises a support side wall that terminates in a bearing surface that cooperates with an outer portion of the charge can when the charge can is in the second connected state, wherein the side wall forms part of the hand support.

4. The spray system of claim 1, wherein the connector is crimped fitted to the top opening to form a permanent and non-removable connection between the cap and the connector.

5. The spray system of claim 1, wherein the inlet fitting and outlet fitting are keyed fittings such that inlet fitting can only connect to a correspondingly configured outlet fitting.

6. The spray system of claim 1, wherein inlet fitting is a female configured fitting allowing fluid flow only into the interior cavity.

7. The spray system of claim 1, wherein the interior cavity of the disposable container is configured to hold a pressurized fluid at about 80 to about 100 psig and the inside portion of the charge can when in the first disconnected state is at a pressure greater than 80 psig.

8. The spray system of claim 1, wherein the interior portion of the charge can is configured to hold a pressurized fluid at about 80 to about 100 psig.

9. The spray system of claim 1, wherein the charge can contains a propellant and a catalyst.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The advantages and features of the present disclosure will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which:

(2) FIG. 1 is a schematic representation of one configuration of the complete spray system of the present disclosure;

(3) FIG. 2 is a disassembled view of the spray system of FIG. 1;

(4) FIG. 3 is a disassembled view of a first subassembly of the sealing cap and valve assembly of the spray system of FIG. 1;

(5) FIG. 4 is a disassembled view of a second subassembly of the spray system of FIG. 1 where the fill cup (disposable container) is formed from an injection molding process where the inlet fitting has yet to be attached to the bottom of the fill cup cap;

(6) FIG. 5 is a schematic representation of the fill cup of FIG. 4 where a liquid formulation has been added to the interior cavity and a metal inlet fitting has been secured to the bottom of the fill cup; and

(7) FIG. 6 is a schematic representation of the fill cup of FIG. 5 where the sealing cap and valve assembly have been attached to the top portion of the fill cup to created a sealed interior cavity.

DETAILED DESCRIPTION

(8) The spray system of the present invention allows any type of homogenously mixed liquid formulation to be discharged in atomized spray pattern onto a substrate or merely into the atmosphere in the case of an air freshener or bug spray. Preferably, the liquid would be a paint mixture, either a solvent based, water based or latex based paint mixture. FIGS. 1-6 show a preferred embodiment of the present disclosure.

(9) Turning to FIG. 1 there is shown one embodiment of the complete spray system 100 of the present disclosure having a fill cup (disposable or reusable) 1 that has an interior volume or cavity 5 (see FIG. 2). This container can be manufactured from any known polymer material, preferably a plastic composition that is biodegradable. Likewise, the fill cup can be fabricated from low-cost materials such as tin, aluminum or like materials, especially in the case where the fill cup is designed as a disposable, non-reusable container. Regardless of the material of construction, it is essential that the fill cup can withstand internal pressurization of about 100 psig, and at least 80 psig. The volume 5 should be at least capable of holding greater than 2 oz. of liquid, most preferably greater than 5 oz. of liquid. At the upper end of fill cup 1 there is a connector, shown as screw thread 3b in the particular embodiment illustrated in FIG. 2, however, any type of connector can be used provided that it can mate with a like connector 3a on sealing cap 2. The connectors 3a, 3b must be capable of sealing the fill cup 1 with cap 2 such that it can maintain an internal pressure in volume 5 of at least 50-80 psig, most preferably greater than 100 psig.

(10) Cap 2 can be made of any material that allows it to connect and maintain a pressure seal with container 1. Preferably, cap 2 is made of the same disposable material as used to fabricate container 1. Cap 2 has an orifice or opening 6 that is generally centered in the top of the cap and is configured to accept and/or allow attachment of a valve assembly 7 (see FIG. 2). A protective, removable small cap 4 is configured to temporarily cover and protect opening 6 until the valve assembly 7 is ready to be installed/connected to sealing cap 2 of container 1. The bottom of container 1 may also have an inlet fitting 9 that provides for fluid communication with the interior cavity of container 1. The inlet fitting 9 is configured as a separate component that is attached to the bottom of the fill cup 1 so as to allow fitting 9 to be accessed for attachment of a pressure source, such as the charge (pressurized) can 21 as illustrated in FIG. 1. Fitting 9 can also have a one-way check valve 9a allowing fluid flow only into, and not out of, the cavity 5.

(11) FIG. 4 shows support side walls 125 that can be of a length such that when the outlet and inlet fittings are connected such that the propellent can transfer to the fill cup 1, the bearing surface 126 is in tight engagement with the upper edge of the charge can such that the charge acts a support for the fill cup and also function as a hand support for the user when spraying the pressurized liquid formulation through the nozzle.

(12) Container 1 can contain any liquid 50 that can be sprayed/atomized (see FIG. 5). Preferably, the container is pre-filled at a manufacturing location with a paint base selected from the group comprising a water soluble, solvent based, or latex paint base. The container could also be filled at the point of sale by a retailer after selection of the liquid by the consumer. In the case of a paint base, the addition of tints or other coloring or paint enhancement compounds could be added to the paint base before final assembly and pressurization of the spray system of my invention.

(13) As illustrated in FIGS. 2 & 3, valve assembly 7 comprises a dip tube 8, and a pressure seal 10. In one possible use of the spray system, the cap 2 fixedly attached to the fill cup 1, with small protective cap 4 in place on the top opening 6, is removed from the upper end 11 of the fill cup 1 and an additional liquid that is to be sprayed/atomized is placed into volume 5, which preferably already contains a base paint formulation when it was manufactured and shipped from the supplier to the retail store. Alternatively, the sealing cap 2 and fill cup 1 can remain securely connected through connectors 3a, 3b and instead protective cap 4 is removed and discarded, and the additional liquid is added to cavity 5 through the top opening 6.

(14) Once the additional liquids or in some cases powders are added to the volume (cavity) 5, then either sealing cap 2 is attached through connectors 3a, 3b forming a pressure seal or in the latter possible embodiment, the valve assembly 7 is secured to top opening 6. In some circumstances it may be desirable to add solid mixing elements, such as metal or plastic balls, to aid in mixing the contents of the cavity after the fill cup is sealed shut and pressurized. The liquid filled fill cup 1 is now ready for connection to the charge can 21.

(15) Charge can 21 has an exit or outlet fitting 20 that may mate/connect directly to inlet fitting 9 located at the lower part of the fill cup 1. Any type of fittings can be used provided the type selected allows for transfer of a pressurized fluid between the charge can 21 and the interior volume 5 of the fill cup 1 through inlet fitting 9. In a preferred embodiment the fittings are selected so that they are specifically keyed to each other and will not attach/connect to another manufacturer's fitting. In this way the charge can from one manufacturer/supplier cannot be inadvertently connected/attached to the inlet fitting 9 from the manufacturer/supplier of the fill cup 1.

(16) The charge can 21 can be pre-filled by a manufacturer with a specific type of propellant that is compatible with the specific type of liquid contained in the fill cup 1. The charge can is pressurized to above 50 psig, preferably above 100 psig, by introducing compressed air, nitrogen, carbon dioxide, or other relatively inert gas or mixtures of gases. Charging of the charge can 21 with pressure and a propellant could be performed by the manufacturer of the charge can or also be performed at a retail point-of-sale location. For example, if the liquid in a 10 oz. fill cup 1 was a solvent based paint base, then approximately 2.5 oz. of dimethyl ether propellant could be added (charged) to the charge and then pressurized to 100 psig with compressed air. In addition to the propellant and pressurized gas, other ingredients could be added, such as a catalyst formulation that allows, for example, quick drying of a sprayed paint mixture. Such catalyst formulations could include any component which accelerates a chemical reaction between two or more other components, for example metal salts and poly-isocyanate resins. These catalysts can accelerate drying of the final spray product and/or cause a reaction to start as in the case of an epoxy. Other compounds could be added to the charge can, such a gloss formulations, polyesters, gel coats, acrylics, and polyurethane. Paint types include acrylic lacquer, acrylic enamel, acrylic urethane and water-based, more simply referred to as lacquers, enamels, urethanes and water-based.

(17) With the final formulation of liquid now inside volume 5 of the fill cup 1, the charge can 21 is connected to inlet fitting 9 of the fill cup 1 (see FIG. 1). Because the pressure in the charge can is much greater than the atmospheric pressure, i.e., 0 psig, of volume 5, the contents of charge can 21 is driven or forced into volume 5 to mix with the liquid initially present. This forms a homogeneous mixture. The transfer can be automatic upon connection of the fittings or alternatively, there could be an optional valve (not shown) to activate after the fittings are connected. In either case the transfer of the components in charge can 21 is very fast. Optionally, a pressure gauge (not shown) could be associated with the charge can and one or more check valves such that the user could visibly observe that the transfer is or has occurred.

(18) After transfer of the contents of the charge can 21 into fill cup 1, the charge can may remain connected to the fill cup or the charge can be disconnected from the inlet fitting, removed from the system, and then discarded for disposal or for re-charging and re-use with another system. A spray head 25 can then be attached to valve fitting 7 (see FIG. 6) and the system is now ready for use. Aerosol spray heads are well known, and the presently disclosed system is easily adapted to accept known designs.

(19) FIG. 3 shows one possible configuration for a manufacturing cap subassembly 110 and FIGS. 4-6 shows different manufacturing stages of a fill cup subassembly 120.

(20) The present disclosure has been described with reference to a preferred embodiment. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding specification. It is intended that the embodiments of the present disclosure be construed as including all such alterations and modifications insofar as they come within the scope of the appended claims or the equivalents thereof.