Patent Application
20170326566
The present invention relates to manual liquid sprayers generally, and more particularly to a liquid sprayer apparatus that permits semi-continuous emission with discontinuous manual pumping.
Liquid spray apparatus are widely used in a variety of applications. The simplest form of a liquid spray apparatus involves a manual pump mechanically connected to a piston that operates to draw liquid from a container, and also to discharge liquid from a collection chamber. For many apparatus, a manual pump trigger is actuated by the user to move a piston in a collection chamber against a spring force to discharge liquid from the collection chamber out through an orifice. Upon release of force against the actuator, the spring force acts to push the piston back toward an initial position, wherein a reduced pressure is developed in the collection chamber as a motive force to drive liquid from the container into the collection chamber. Typically, one-way valves at the inlet and the outlet of the collection chamber control the collection and discharge of the liquid. In this common arrangement, liquid is dispensed from the sprayer only as the actuator is manipulated to move the piston through the collection chamber during the “discharge” portion of the cycle. In other words, liquid is not dispensed from the sprayer apparatus during the “collection” portion of the pumping cycle.
Another common type of liquid spray apparatus is a pressure sprayer, in which a pressure, typically pneumatic, is developed in a chamber through either manual or automatic means. Release from the pressure chamber is controlled by a valve that may be selectively operated by the user to introduce an elevated pressure into a liquid chamber, thereby driving liquid out from the liquid chamber through an orifice. Liquid emission will continue for so long as sufficient driving pressure is available in the pressure chamber. While pressure sprayers are useful for continuous spray applications, the mechanisms involved are typically more expensive to produce than the manual individual pump cycle spray apparatus described above, since pressure sprayers require a pressure chamber separate from the liquid chamber, and/or additional valving to accommodate the pressurization mechanism.
A need therefore exists for a liquid spray apparatus that is capable of continuous or semi-continuous emission in a compact and inexpensive manual pump spray mechanism. With such an apparatus, the user is able to maintain liquid emission for a period of time between pumping actions.
By means of the present invention, a liquid spray apparatus may exhibit a spray dispensation time that is substantially greater than a discharge phase of a pump cycle of a manual pump mechanism. The liquid spray dispensation time may be extended through the use of an adjustable volume dispensation chamber, in coordination with an outlet orifice of desired dimension. The adjustable volume dispensation chamber is facilitated by a movable piston acting against fluid pressure developed in the manual pumping action. Liquid spray dispensation initiates upon reaching a threshold fluid pressure in the dispensation chamber, and ceases when the fluid pressure drops below either the same or another threshold.
In one embodiment, a liquid sprayer apparatus includes a liquid container having an opening, and a spray mechanism sealingly engagable to the liquid container adjacent to the opening in order to fluidically communicate with an interior of the liquid container. The spray mechanism includes a main body defining a first channel with a first channel wall and a second channel with a second channel wall fluidically connected to each other through a first passage. A charge piston coordinates with the first channel wall to define a collection chamber, with the charge piston itself defining a third channel through which liquid may be introduced to the collection chamber. A one-way inlet valve permits liquid flow from the container to the collection chamber. The spray apparatus further includes a dispensation piston and a discharge valve base coordinating with the second channel wall to define a dispensation chamber, wherein the dispensation piston is responsive to a fluid pressure in the dispensation chamber. A one-way outlet valve permits liquid flow from the collection chamber to the dispensation chamber through the first passage. An actuator is provided with the spray apparatus for selectively moving the charge piston with respect to the first channel wall against a first restorative force to reduce a collection chamber volume of the collection chamber. A one-way discharge valve is provided to permit liquid flow from the dispensation chamber through a second passage in the discharge valve base, wherein the discharge valve includes a plunger with a sealing portion sealingly engagable with an aperture in a discharge valve seat structure, wherein the dispensation chamber is fluidly connected to the second passage through the aperture when the discharge valve is open with the sealing portion of the plunger disengaged from the discharge valve seat structure, the plunger being responsive to the fluid pressure in the dispensation chamber.
The objects and advantages enumerated above together with other objects, features, and advances represented by the present invention will now be presented in terms of detailed embodiments described with reference to the attached drawing figures which are intended to be representative of various embodiments of the invention. Other embodiments and aspects of the invention are recognized as being within the grasp of those having ordinary skill in the art.
With reference now to the drawing figures, a liquid sprayer apparatus 10 includes a liquid container 12 and an opening 14 for access to interior 16 of liquid container 12. A neck 18 may surround opening 14, and may provide a convenient location for engagement with spray mechanism 20.
A skirt closure 22 may engage with neck 18, such as through a threadable engagement. A gasket 24 is supported by a valve base 26 to create a sealing engagement with neck 18 of liquid container 12 when skirt closure 22 securely engages with neck 18. Valve base 26 is secured to main body 28, which defines a first channel 30 with a first channel wall 32 and a second channel 34 with a second channel wall 36. The first and second channels 30, 34 of main body 28 may be fluidically connected through a first passage 38.
A charge piston 40 coordinates with first channel wall 32 to define a collection chamber 42 having a valve-controlled inlet 44 and a valve controlled outlet 46. As illustrated in
In the illustrated embodiment, charge piston 40 includes a first portion 41 that is in slidable engagement with first channel wall 32 to define at least a portion of collection chamber 42. Charge piston 40 includes a second portion 49 that defines third channel 50 through which fluid flow may be directed from liquid container 12 to collection chamber 42 (through valve-controlled inlet 44). Second portion 49 is slidable with respect to valve base 26, and sealingly engaged thereto with, for example, an O-ring gasket 54.
An actuator 56 includes a trigger portion 58 and a lift portion 60, wherein actuator 56 is secured to main body 28 at a pivot 62. Operation of actuator 56 occurs through the application and release of force against trigger portion 58, wherein an applied force against trigger portion 58 causes rotation of actuator 56 about pivot 62, which, in turn, rotates lift portion 60 about pivot 62. In the illustrated orientation, application of force against trigger portion 58 results in generally counter-clockwise rotation of lift portion 60 about pivot 62. Actuator 56 is mounted with lift portion 60 adjacent to bearing surface 43 of charge piston 40, so that rotational movement of lift portion 60 about pivot 62 moves charge piston 40 with respect to first channel wall 32. Such movement is applied against a first restorative force that is generated by, for example, a first spring 64. Other devices, such as elastic or resilient bodies, and the like are also contemplated as being capable of generating the first restorative force against charge piston 40. The first restorative force exerted upon charge piston 40 is transferred to actuator 56 at lift portion 60, to thereby act against an operation force applied to trigger portion 58. In the absence of an operational force upon trigger portion 58, therefore, actuator 56 is urged by first spring 64 to rotate about pivot 62 to a base condition. Movement of charge piston 40 with respect to first channel wall 32 adjusts a collection volume of collection chamber 42. In the illustrated embodiment, collection chamber 42 is defined by surfaces of one-way inlet valve 48, charge piston 40, first channel wall 32, one-way outlet valve 66, and outlet valve base 68 to which outlet valve 66 is secured. Outlet valve base 68 is secured to main body 28.
Spray mechanism 20 may further include a dispensation piston 70 that coordinates with second channel wall 36, as well as with a discharge valve base 80 and a discharge valve 90 to define a dispensation chamber 72 that is fluidically connected to collection chamber 42 through valve-controlled outlet 46 and first passage 38. In the embodiment illustrated in
Discharge valve base 80 may be secured to main body 28 to aid in positioning discharge valve 90 and dispensation piston 70 in second channel 34. In some embodiments, one or more of stop flange 82 and end flange 84 of discharge valve base 80 may act as a stop limiter to arrest movement of dispensation piston 70 at the urging of the second restorative force in the absence or insufficiency of a fluid force exerted by a fluid pressure in dispensation chamber 72. The illustration of
Discharge valve 90 is arranged for permitting liquid flow from dispensation chamber 72 through a second passage 86 in discharge valve base 80, wherein discharge valve 90 opens when the fluid pressure in dispensation chamber 72 exceeds a first threshold pressure. In some embodiments, discharge valve 90 includes a plunger 95 urged into contact with a discharge valve seat structure 96 by a third restorative force when discharge valve 90 is in a closed condition. The third restorative force may, in some embodiments, be provided by a third spring 98, though other mechanisms are contemplated as providing the third restorative force in discharge valve 90 to permit one-way fluid flow out from dispensation chamber 72. Each of inlet valve 48, outlet valve 66, and discharge valve 90 are illustrated in
In another embodiment illustrated in
A shroud 104 may be removably secured to main body 28 for both aesthetic and functional purposes. Tube 106 may be provided for conveying liquid from container 12 to third channel 50 of charge piston 40. In at least some embodiments, tube 106 may be connected to second portion 49 of charge piston 40, wherein tube 106 moves with charge piston 40, as driven by actuator 56 and first spring 64. Accordingly, tube 106 may preferably be sufficiently long to maintain submersion in the liquid in container 12 when tube 106 is moved upwardly with charge piston 40 during a pump cycle.
As described herein, an aspect of the present invention is the continuous or semi-continuous liquid emission from spray mechanism 20 during and between repeated pump cycles to actuator 56. The relationship among dispensation piston 70 and discharge valve 90, 190 with the fluid pressure in dispensation chamber 72 permits extended liquid discharge intervals that may continue for a period of time after actuator 56 (and charge piston 40) have ceased to be moved against the first restorative force. Such extended time liquid discharge may be facilitated by dispensation piston 70, and the potential energy accumulated by second spring 76 as a result of fluid pressure buildup in dispensation chamber 72. Conversion of the accumulated potential energy in second spring 76 to kinetic spring expansion energy may arise when a first threshold pressure in dispensation chamber 72 is exceeded, causing discharge valve 90, 190 to open and permit discharge of liquid from dispensation chamber 72 out through second passage 86, and ultimately out from spray mechanism 20 at orifice 100 of nozzle 102. In this manner, liquid discharge from spray mechanism 20 may occur independently from the operational status of actuator 56, in that liquid discharge may occur even when an operating force has been removed from trigger portion 58 to allow first spring 64 to urge charge piston 40 back to a base position.
Operation of an example embodiment of the present invention will now be described with reference to
Fluid entering into dispensation chamber 72 exerts a fluid pressure, which acts against all surfaces to which the liquid is exposed, including dispensation piston 70. The force “F2” results in displacement of dispensation piston 70 against the second restorative force, thereby expanding the dispensation volume of dispensation chamber 72. Each of discharge valve 90, 190 and dispensation piston 70 represent movable structures exposed to fluid pressure in dispensation chamber 72. Such movable structures are adapted to yield to pressure, but preferably initially yield at different pressure thresholds, and may also yield at different yield rates. In particular, it is desired that dispensation piston 70 yields with movement against its second restorative force at a lower pressure than that required to cause plunger 95, 195 of discharge valve 90, 190 to yield with movement against its third restorative force. In this manner, as fluid pressure builds in dispensation chamber 72, dispensation piston 70 moves against its second restorative force before discharge valve 90, 190 opens.
In order to fulfill a purpose of the present invention, a mechanism is preferably provided to generate a dispensable liquid reservoir through a manual pumping action, wherein the liquid reservoir is released over a period of time that is equal to or greater than a pump cycle time period, which includes a “discharge phase” of operating actuator 56 to reduce volume in collection chamber 42, and a “collection” phase in which force is removed from actuator 56 to permit collection chamber volume to expand with a new liquid charge. One approach for developing such a liquid reservoir may be to manually pump liquid into a chamber of fixed volume. Once the pressure in the fixed-volume reservoir exceeds a threshold pressure of an outlet valve, the outlet valve may open to dispense the liquid at a metered rate. Such an approach, however, would likely result in operational challenges, in that the manual pumping operation would require inequal and dramatically increasing force on actuator 56 in an effort to continue to fill an already “filled” fixed-volume chamber. In fact, due to the incompressible nature of many liquids, desired pressure buildup in the reservoir would quickly become impossible under typical manual pumping forces. Instead, dispensation chamber 72 of the present invention utilizes an adjustable-volume chamber 72 so that fluid pressure builds only with an increasing restorative force generated by second spring 64 as dispensation piston 72 is displaced against the increasing restorative force of second spring 64. This approach limits resistance to continued filling of dispensation chamber 72, while nevertheless generating a reservoir for extended time liquid dispensation from spray mechanism 20.
A measure of yield resistance for dispensation piston 70 and discharge valve 90, 190 may be defined herein as a “pressure resistance”, which is determined as follows:
R=F/A
Wherein:
As described above, the restorative force applicable to dispensation piston 70 is the second restorative force, supplied in the illustrated example by second spring 76. The restorative force applicable to discharge valve 90, 190 is the third restorative force, generated in the illustrated example by third spring 98, 198 applied against plunger 95, 195. It should be understood that the applicable restorative force is dependent upon the mechanism employed to urge the movable structures against fluid pressure in dispensation chamber 72. In some embodiments, the restorative force may be determined or approximated pursuant to Hooke's Law, which is a principle that states that the force needed to extend or compress a spring by some distance is proportional to that distance:
F=k*X
Wherein:
It should also be understood, however, that Hooke's Law is only a first-order linear approximation to the real response of springs and other elastic bodies to applied forces. The general principle, however, of increasing restorative force with increasing displacement from a neutral position holds true with respect to the restorative forces contemplated in the present invention. That is, as displacement of the movable body is increased, so too will the restorative force acting against the associated movable structure. In the case of the dispensation piston 70, for example, the second restorative force increases with displacement of dispensation piston 70 under the fluid force, F2.
The effective surface area (A) of the movable structure exposed to fluid pressure in dispensation chamber 72 is defined herein as the area of a profile surface that is normal to the applicable restorative force. A schematic illustration of a profile surface area of a hypothetical frusto-conical movable structure analogous to plunger 95 of discharge valve 90 is illustrated in
The profile surface area of plunger 195 of discharge valve 190 is the area of shoulder portion 197 normal to the third restorative force. As in the embodiment of discharge valve 90, the effective surface area of dispensation piston 70 exposed to fluid pressure in dispensation chamber 72 is substantially greater than the effective surface area of plunger 195 exposed to the fluid pressure in dispensation chamber 72.
A further condition of spray mechanism 20 is illustrated in
To aid in extending the time period for dispensing liquid from spray mechanism 20 while discharge valve 90, 190 is in an open condition, orifice 100 may have a diameter that develops a desired flow restriction, thereby generating a back pressure to liquid flow out from orifice 100. In one aspect of the present invention, a liquid dispensing time is at least twice the discharge phase time of the pump cycle, and may more preferably be at least thrice the discharge phase time of the pump cycle. For the purposes hereof, the term “dispensation time” means the time of liquid dispensation out from orifice 100 for each discharge valve opening cycle, which itself is defined by the cycle from discharge valve open to discharge valve close. For the purposes hereof, the term “discharge phase time” is intended to mean the time of movement of charge piston 40 in forcing liquid from collection chamber 42 through outlet 46 for each pump cycle operation applied to actuator 56. By way of example, one discharge phase occurs during the time that a user depresses actuator 56. In some embodiments, orifice 100 may be in the range of between about 0.3-0.5 mm and more preferably between about 0.35-0.45 mm. Such diameter range is exemplary only for a particular embodiment, and is intended to demonstrate an appropriate orifice size for generating a flow restriction suitable to extend liquid dispensation cycle times.
Discharge valve 190 is preferably configured to close aperture 194 immediately upon the fluid pressure in dispensation chamber 72 falling below the threshold pressure and, in some embodiments, below the first threshold pressure. It is desirable that liquid flow along pathway L2 out from orifice 100 changes abruptly from an “on” condition to an “off” condition. To do so, plunger 195 is arranged to immediately re-seat with discharge valve seat structure 196 with a corresponding drop in fluid pressure in dispensation chamber 72. Thus, plunger 195 preferably includes a sealing portion 195A that quickly engages with discharge valve seat structure 196 and effectively closes aperture 194 to thereby close discharge valve 190. In the illustrated embodiment, sealing portion 195a of plunger 195 may have a substantially frusto-conical configuration that is engagable into a correspondingly-configured aperture 194 of discharge valve seat structure 196 to close discharge valve 190.
The invention has been described herein in considerable detail in order to comply with the patent statutes, and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use embodiments of the invention as required. However, it is to be understood that various modifications may be accomplished without departing from the scope of the invention itself.
The present application is a continuation-in-part of U.S. patent application Ser. No. 15/150,617, filed May 10, 2016, entitled “EXTENDED EMISSION TIME LIQUID SPRAYER”, the content of which being incorporated herein in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15150617 | May 2016 | US |
| Child | 15216847 | US |
