Fluid Dispenser Method and Apparatus

Aerosol dispensers, which are widely used in the packaging industry, present two major problems, atmospheric pollution from the propellant and disposal of the cannister without the risk of explosion and the accompanying hazard to personal safety. The use of hand actuated pump dispensers as a substitute for aerosol dispensers obviates these problems.

Typical pump dispensers presently on the market incorporate a manually operable reciprocating pump mechanism as part of a screw-on closure for a container so that the dispenser may be removed from the container for refilling the container. Such dispensers may have a trigger member, plunger or other protruding element which is intended to be moved manually to operate a pump piston in the dispenser, usually against the force of a return spring, so that liquid may be pumped from the container and dispensed through the liquid ejection nozzle or outlet of the device.

To meet consumer demands for convenience it has been found highly desirable that the nozzle be adjustable to provide widely varying discharge patterns, i.e. a spray pattern and a stream pattern. Exemplary of such nozzles are the ones described in U.S. Pat. Nos. 3,843,030, 3,967,765 and 3,685,739. Since it is also highly desirable that the dispensers should have the ability to be attached to the container for shipment, it is mandatory that the dispenser be capable of acting as a liquid-tight closure for the container during shipment. This liquid-tight characteristic should be present even if the container is tipped over on its side and remains in such position for a long period of time. To achieve this characteristic the dispensers disclosed in the above-mentioned patents all have an "Off" position which is designed to close off the nozzle opening to prevent leakage therethrough. However, the consumer is not always that observant and will, on many occasions, leave the nozzle in the "Spray" or "Stream" position which will result in the nozzle being open to leakage should the container be tipped over. Also, it is possible that leakage could occur should the nozzle be inadvertently packaged in a position which places the containers upside down or on their sides.

The answer to this problem is to provide the dispenser with a static seal which is not dependent upon whether or not the dispenser nozzle is in an open or closed position. A highly useful dispenser design which provides such structure is described in U.S. Pat. No. 4,161,288. This structure is capable of providing multiple dispensing patterns and is capable of maintaining a liquid-tight seal at the nozzle irrespective of whether or not the nozzle is adjusted to the open or closed position. This design, however, is not without certain drawbacks. Referring to the disclosure in this patent, it is seen that a flexible nozzle check valve is provided which fits onto the nozzle barrel and closes the pump bore off. Due to the valve design and the fact that the valve is of an elastomeric material, e.g. thermoplastic rubber, the pump bore is sealed off when there is no fluid pressure applied against the nozzle check valve through the pump bore. In this mode the situation is static and no leakage is possible through the bore even should the container be tipped over. To dispense the product the liquid-tight seal made by the nozzle check valve is broken by the force of the fluid being pumped through the bore and against the valve. Since the valve is made of elastomeric material, it is able to expand out in response to such force and allow the fluid to be dispensed. When the fluid pressure is relieved, such as at the end of the pumping stroke, the nozzle check valve can return to its seated position sealing off the pump bore. But because of the necessity of using an elastomeric material for the valve, difficulty is encountered when the product to be dispensed is such that it interacts with the elastomeric material and causes the nozzle valve to lose its elastic quality or to swell. Exemplary of products which have been found to have adverse reactions with elastomeric materials are petroleum distillates, hydrocarbon solvents, etc. Thus, even though the dispenser shown in U.S. Pat. No. 4,161,288 has many advantages and is capable of providing a multipattern dispensing mode and is able to achieve static sealing of the pump bore, it is still incapable of handling materials which react adversely with the nozzle check valve.

Therefore it is an object of the present invention to provide a nozzle system which is usable on manually operated reciprocating dispensing pumps, which has multiple dispensing modes, which is capable of achieving a static seal over the pump bore, and which is capable of handling products not manageable by present day elastomeric materials.

This invention relates to a nozzle fittable to hand actuated liquid pumps having a barrel portion with a bore therethrough for the passage of liquid. Exemplary of such pumps are the ones disclosed in U.S. Pat. Nos. 3,685,739, 3,840,157 and 4,161,288. The nozzle of this invention is usable on other pump configurations, the only requirement being that the liquid pumped through the bore must be pumped at a pressure sufficient to operate the check valve and achieve the desired dispensing pattern, e.g. spray, stream, etc.

The nozzle of this invention has, as one of its parts, an integrally formed nozzle cap. The cap mounts to the end of the pump barrel and has an end wall with an aperture therethrough for passage of the liquid from the bore as it is dispensed. Enclosed by the nozzle cap is an integrally formed sealing structure which is attached to the end of the barrel. The sealing structure has a peripheral liquid-tight seal portion and a check valve portion. The peripheral liquid-tight seal portion forms a seal around the barrel between the nozzle cap and the barrel. This seal prevents leakage, to the outside, of liquid which is pumped into the space between the nozzle cap and sealing structure.

A check valve portion is movably positioned at the mouth of the bore. The check valve has a seal member which selectively forms a liquid-tight bore seal at the bore mouth to close off the flow of liquid through the bore. The check valve portion also has a spring member connected to the seal member whereby the spring member biases the seal member to form its liquid-tight bore seal. While the spring member has sufficient strength to achieve this liquid-tight bore seal it does not have sufficient strength to maintain this seal against liquid pressure which builds in the bore as the pump is actuated. Upon actuation of the pump, therefore, the liquid-tight bore seal is opened thereby allowing liquid to pass through the bore to the aperture in the end wall of the nozzle cap.

The components of the nozzle of this invention, due to their unique configuration and to their relationship with one another, do not require the use of elastomeric material but rather can be made of a thermoplastic such as polyethylene or polypropylene. Since polyethylene and polypropylene have a high resistance to damage or swelling by various hydrocarbons and/or solvents the nozzle of this invention can maintain fidelity of operation even when these materials are dispensed by the pump.

It is also possible with the nozzle of this invention to provide a nozzle having a shut-off mode, a first dispensing mode and a second dispensing mode. The shut-off mode is effected by moving the nozzle cap so that the inside surface of the end wall presses against the check valve portion to prevent its movement from the end of the bore. The first dispensing mode, which can be a spray mode, is achieved by providing the nozzle end wall with a planar inside surface at the aperture and by providing the check valve portion with a planar face which is abutable with the planar inside surface at the aperture. The planar face will have liquid passage channels for providing a spray pattern when the planar face is abuted against the planar inside surface and liquid passes through the channels. The configuration of these channels can be any of the conventional "swirl chamber" configurations which are well known to those skilled in the art for achieving break-up of the liquid stream to provide the spray dispensing mode. To provide abutment of the planar face against the planar inside surface of the nozzle cap while at the same time allowing opening movement of the check valve portion it is necessary that the nozzle cap be moved away from the bore. The distance moved, however, cannot be so far that the planar face is unable to reach an abutting position upon the urging of liquid pressure against the check valve portion. Upon actuation of the pump the check valve portion will be urged forward of the bore until the planar face achieves abutment with the planar inside surface of the nozzle cap. When the pressure is relieved at the end of the dispensing stroke the check valve portion moves back to achieve the liquid-tight bore seal and the planar face moves out of abutment with the planar inside surface of the nozzle cap.

In the second dispensing mode, e.g. a stream mode, the nozzle cap is moved further yet from the end of the bore so that the planar face cannot reach the planar inside surface and thus not achieve the necessary abutment. When this occurs the liquid is free to pass through the aperture without going through the liquid passage channels in the planar face which passage would normally result in a spray pattern.

The structure for mounting the nozzle cap to the pump barrel is preferably a helical thread on the nozzle cap which is in cooperation with a helical thread carried by the barrel. By utilizing helical threads it is thus easy to position the nozzle cap at any selected distance from the check valve portion and the pump bore.

These and other features of this invention contributing satisfaction in use and economy in manufacture will be more fully understood from the following description of a preferred embodiment and the accompanying drawings in which identical numerals refer to identical parts and in which:

FIG. 1 is a partially broken away side elevational view of a nozzle of this invention attached to a hand actuated pump;

FIG. 2 is a sectional side elevational view of the nozzle shown in FIG. 1 with the nozzle in the closed position;

FIG. 3 is a sectional side elevational view of the nozzle shown in FIG. 1 with the nozzle in the spray position;

FIG. 4 is a sectional side elevational view of the nozzle shown in FIG. 1 showing the nozzle in the stream position;

FIG. 5 is a front view of the sealing structure used in the nozzle shown in FIG. 1; and

FIG. 6 is a rear elevational view of the sealing structure utilized in the nozzle shown in FIG. 1.

In FIGS. 1-6 there can be seen a nozzle of this invention, generally designated by the numeral 18. The nozzle is affixed to a hand-actuated pump, generally designated by the numeral 10. Pump 10 is affixed to a container by means of pump closure cap 12. Closure cap 12 forms a liquid-tight seal with the container so that the contents of the container cannot leak out should the container be tipped over. Pump housing 16 encloses the pumping mechanism for pumping the liquid from the container upon actuation of pump trigger 14. The particular design of the pump mechanism is not critical to the operation of the nozzle of this invention as long as sufficient liquid pressure is provided upon actuation of the pump to operate the nozzle parts as hereinafter described.

Nozzle 18 is affixed to the barrel of the pump, indicated by the numeral 20. Barrel 20 has a helical thread 21 which cooperates with nozzle cap thread 36 for affixing nozzle 18 to the pump. Nozzle 18 has two component parts, a nozzle cap 30 and a seal structure 38. Nozzle cap 30 has a nozzle cap end wall 33 with a dispensing aperture 32 therethrough. There is provided a planar inside surface 34 on the inside of nozzle cap end wall 33. Inside surface 34 surrounds dispensing aperture 32. Integrally formed with nozzle cap end wall 33 is nozzle cap skirt 31. This skirt carries the afore-described nozzle cap thread 36.

Nozzle cap 30 encloses seal structure 38. Seal structure 38 is mounted to the end of barrel 20 by means of a friction fit over collar 26 which is located at the end of barrel 20. Achieving the precise location of seal structure 38 with respect to the end of barrel 20 is accomplished by means of annular collar 24 which is an integral part of barrel 20. This collar acts as a stop structure for positioning seal structure 38. Seal structure 38 is integrally formed and has a peripheral seal portion 40 and a check valve portion 36. To achieve the peripheral liquid-tight seal function required of seal portion 40 there is provided sealing lip 42. Sealing lip 42 is dimensioned to achieve a peripheral liquid-tight engagement with nozzle cap 30 as is seen in FIGS. 1-4. Sealing lip 42 therefore prevents leakage between barrel 20 and nozzle cap 30. Other sealing arrangements, of course, may be utilized, the one utilized by the embodiment shown in the drawings being a preferred configuration.

Check valve portion 46 has a seal member 48 and a spring member 50. Seal member 48 preferably provides a conical surface 54 which co-acts with annular groove 28 to provide an openable and closeable liquid-tight seal. Connected to the distal end of conical surface 54, as can be seen, in FIGS. 2-4, is spring member 50. For the embodiment shown spring member 50 comprises three arcuate segments which are dimensioned to be sufficiently resilient to provide the necessary spring function as hereinafter described.

Check valve portion 46 preferably has a planar face with a swirl chamber 62 molded therein. When swirl chamber 62 is in abutment with the planar inside surface 34 of nozzle cap 30 the swirl chamber will force the liquid to travel a path which will give a spray pattern. While the specific swirl chamber configuration shown in the drawings is a highly preferred configuration, it is understood that other configurations known in the art can be utilized to achieve this same function.

The particular nozzle shown in the drawings is one which is capable of effecting three modes of operation, a shut-off mode, a spray mode and a stream mode. In the shut-off mode, shown in FIG. 2, passage of liquid through bore 22 is prevented even if the pump is actuated as check valve portion 46 is blocked from the movement which would open the liquid-tight bore seal as the inside face of nozzle cap 30 is pressing tightly thereagainst. In the other two modes check valve 46 would be free to move under the urging of liquid pressure in bore 22 upon pump actuation.

To achieve the second mode of operation, i.e. the spray mode, nozzle cap 30 is loosened until it is displaced a distance away from check valve portion 46 so that seal member 48 is able to move and thus open the liquid-tight bore seal between conical surface 54 and annular groove 28. This mode is shown in FIG. 3. However, nozzle cap 30 will still be close enough to check valve portion 46 whereby the planar face of check valve portion 46 can abut inside planar face 34. The abutment is necessary to force the liquid to pass through swirl chamber 62 to effect the spray dispensing pattern. With nozzle cap 30 in the spray position the pump is actuated by pulling trigger 14. Liquid pressure builds in bore 22 until it is sufficient to overcome the spring bias provided by spring member 50. Once the spring bias has been overcome seal member 48 moves to open the liquid-tight bore seal and thus allows the pumped liquid to be forced through swirl chamber 62 and out aperture 32. After a charge of liquid has been dispensed pump trigger 14 is released. Upon trigger release, seal member 48 returns to the seal position to provide a liquid-tight bore seal at the urging of spring member 50. In some prior art pumps, e.g. U.S. Pat. No. 3,685,739, closing off of the bore after liquid has been dispensed relies upon the creation of a partial vacuum carried by the pump during its loading cycle. With these types of pumps there is a period of time before the bore can be closed off that air is sucked into the bore and into the pump chamber. This is disadvantageous as the sucked in air displaces liquid in the pump chamber and thus the subsequent charge of liquid will be of a reduced quantity. However, for the nozzle of this invention, the return of seal member 48 to the seal position is effected by spring action means which is acting against liquid in bore 22. Thus there is a very little, if any at all, amount of air being sucked into the bore. By keeping air out of the bore a full charge of liquid is assured in the pump chamber.

To achieve the third mode of operation, nozzle cap 30 is screwed further away from check valve portion 46 so that the travel of seal member 48 is unable to achieve abutment between the planar face of seal member 48 and the planar inside surface 34 of nozzle cap 30. Since there is no abutment the liquid is allowed to pass to dispensing aperture 32 without passing through the swirl chamber and thus a stream of liquid is dispensed instead of a spray. In this mode spring member 50 will return to achieve a liquid-tight bore seal as described for the first modes.

Not only can the nozzle of this invention have a three mode configuration, it is also possible to have a single mode configuration with or without nozzle shut-off. For example, nozzle cap 30 can be mounted to barrel 20 by utilization of a bead and groove snap-on arrangement. With this configuration no shut-off will be available and the distance at which inside planar surface 34 is displaced from check valve portion 46 is fixed. This distance can be fixed so that seal member 48 cannot obtain abutment with the end wall of nozzle cap 30 or so that this abutment can be achieved. If abutment is not achieved there will be a stream dispensing mode or, on the other hand, if abutment is achieved there will be a spray dispensing mode. If it is desired to have a nozzle with a shut-off and spray mode, a configuration similar to the one shown in the drawings can be used with a modification to the cap and barrel threads so that the nozzle cap will be restricted to the extent it can move from the check valve. On the other hand, if a shut-off and stream mode only is desired, then the configuration shown in the drawings may be used with the modification of designing the face of the check valve portion so that the liquid can go directly to the aperture.