Patent Application
20080237266
The invention herein resides in the art of soap dispensers. In particular embodiments, the invention relates to a foam soap dispensing system mounted to a counter, wherein a foam soap pump is mounted under a counter and receives a liquid soap container.
The use of soap dispensers continues to grow as the awareness for the need for good hand hygiene practices grows. Numerous types of dispensing systems are known, including portable, hand held dispensers, wall mounted dispensers, and counter mounted dispensers. Typically, these soap dispensers dispense a predetermined amount of liquid soap upon actuation. Over the past decade or so, interest has grown in foam soap dispensers, wherein air and liquid soap are mixed to form and dispense substantially homogenous foam.
Inline actuated foam soap dispensers are of particular interest because they have a number of drawbacks that can be improved upon. These dispensers include an actuator that is pressed to compress air and soap chambers to force air and soap through a mixing chamber to create foam. The foam is then forced through a dispensing spout. The dispensing tube is coupled to the actuator that is reciprocated to dispense the foam, and thus the dispensing tube moves as the actuator is pressed to dispense product and as it returns to its rest position. These dispensers work satisfactorily in the hand held dispenser embodiments, because the dispensing tube and the spout through which the foam is dispensed are formed in the actuator, and the user can simply place a hand under the spout to catch the foam dispensed therethrough even though the dispensing tube and spout move during dispensing. However these dispensers present problems in a counter mounted environment in which the dispensing tube and spout are decoupled from the actuator.
In the counter mounted dispenser, a liquid soap source is mounted under a counter top and coupled to pumping mechanisms to deliver soap or foam at an outlet of a dispensing tube that extends through a rigid, stationary spout provided above the counter, preferably at a sink basin. The actuator for the dispenser is located proximate the spout and is pressed to dispense foam through the outlet of the dispensing tube. Pressing on the actuator causes air and liquid soap pumps to advance air and soap to be mixed and forced through the dispensing tube. The dispensing tube is coupled to the pump mechanisms such that, as the actuator is reciprocated to cause the pump mechanisms to compress and expand, the dispensing tube reciprocates within the spout. The reciprocation of the dispensing tube within the spout uses up energy in a dispenser that reciprocates the pumps electronically, and requires a larger amount of force to actuate by hand in a manually actuated dispenser.
Most counter mounted soap dispensers also create foam below the counter, proximate the soap and air pump mechanisms, and then force the foam up through a significant length of dispensing tube. This creates a few problems. First, the foam can degrade as it travels through the dispensing tube, yielding a poorer foam product. Second, pushing foam through a length of dispensing tube requires more force than pushing separate air and liquid soap sources, and this makes the actuator for the soap dispenser more difficult to push and, in the case of an electronically activated automatic soap dispenser, requires additional electric power. Published patent application 2006/0011655 shows a counter mounted soap dispenser that creates foam at the spout rather than proximate the pumping mechanisms under the counter, but it is focused solely on a system with separate electronic soap and air pumps and is not structurally similar to inline actuated soap dispensers.
Thus, there exists a need in the art for a foam pump wherein the dispensing tube is stationary during the dispensing of foam and during the refill of the pump with air and liquid. The pumps and dispensers herein will be found suitable for the dispensing of a variety of single or multi-component products. This need is particularly strong in the counter mount environment. This need exists specifically in the dispensing arts for skin care and skin sanitizing products, and, more specifically, the dispensing of foamed soaps and foamed sanitizing products.
In one embodiment, this invention provides a dispenser having a stationary dispensing tube, i.e., the dispensing tube does not move upon actuation of the dispenser to dispense product. The dispenser includes a liquid container holding a liquid, a compressible liquid chamber compressible to a compressed volume and biased to expand to an expanded volume, and a dip tube extending from the compressible liquid chamber into the liquid in the liquid container, wherein compression of the compressible liquid chamber forces liquid within the compressible liquid chamber into the stationary dispensing tube, and expansion of the compressible liquid chamber draws the liquid up through the dip tube and into the compressible liquid chamber. The dispenser further includes a compressible air chamber compressible to a compressed volume and biased to expand to an expanded volume, and an air passage communicating between the compressible air chamber and the stationary dispensing tube, wherein compression of the compressible air chamber forces air within the compressible air chamber into the stationary dispensing tube, and expansion of the compressible air chamber draws air into the compressible air chamber.
In accordance with another embodiment, this invention provides a dispenser that includes a mixing chamber, a compressible liquid chamber, a compressible air chamber, and a dual actuator. The compressible liquid chamber contains a liquid and is adapted to selectively reciprocate between an expanded volume and a compressed volume. The compressible liquid chamber advances the liquid to the mixing chamber when selectively moved to the compressed volume. The compressible air chamber contains air and is adapted to selectively reciprocate between an expanded volume and a compressed volume. The compressible air chamber advances air to the mixing chamber when selectively moved to the compressed volume. The dual actuator is selectively moved to compress both the compressible liquid chamber and the compressible air chamber to their compressed volumes, wherein upon such movement of the dual actuator, the air chamber begins to be compressed prior to the beginning of the compression of the liquid chamber.
For a complete understanding of the structure and techniques of the invention, reference should be made to the following detailed description and accompanying drawings wherein:
Referring now to
Foam pump mechanism 14 fits into container 12 at open end 16. Referring to
Compressible air chamber 18 contains air and is adapted to selectively reciprocate between an expanded volume and a compressed volume. A biasing member 48 forces air piston 40 to a rest position defining an expanded volume for air chamber 18. Compressible air chamber 18 is compressed by forcing air piston 40 against biasing member 48, and a compressed volume is reached. This causes air to be forced through air channel 44 and ultimately into dispensing tube 46. By relaxing the force against biasing member 48, air piston 40 returns to its rest position, reestablishing the expanded volume. As air piston 40 returns to its rest position, air is pulled in back through dispensing tube 46 to fill the expanding volume of air chamber 18, i.e., air is pulled into air chamber 18 through a path opposite to the path the air takes when forced out of air chamber 18. This can help prevent dripping at the spout outlet, as will be described more fully herein below. Optionally, a one-way air valve such as that represented at the numeral 50 can be placed on air piston 40 or elsewhere communicating with air chamber 18.
Compressible liquid chamber 52 is sealed to liquid pump support 30 through retaining ring 54. Dip tube 76 extends through dip tube channel 56 in liquid pump support 30 and through axial channel 57 in axial support 26 to communicate between the volume of container 12 and that of compressible liquid chamber 52 through ball valve 58. More particularly, compressible liquid chamber 52 is formed of a flexible diaphragm 60, which is secured to axial support 26 over valve plate 62 and valve film 64. The volume of compressible liquid chamber 52 may be filled with a sponge material, if desired, to take of some of the volume and help the chamber recover from compression. Valve plate 62 includes inlet aperture 65 and outlet aperture 66 (
Flexible diaphragm 60 is made from a resilient material that naturally rests in the position shown in
As an alternative, the function of ball valve 58 could be replaced with an inlet flap valve in valve film 64 overlying an inlet aperture in valve plate 62. This would provide flow control into and out of compressible liquid chamber 52. Also, flexible diaphragm 60 could be a more rigid chamber and piston design, such as that shown for the compressible air chamber herein.
Thus far, liquid and air have been described to advance from their respective sources, i.e., compressible air chamber 18 and compressible liquid chamber 52, and ultimately into dispensing tube 46. The paths taken by the liquid and air are now more particularly disclosed. First, it should be appreciated that dispenser 10, upon first being constructed, will have liquid product P in container 12, and compressible liquid chamber 52 will be empty. With repeated compression and expansion of compressible liquid chamber 52, liquid product will be incrementally advanced up through dip tube 76 and into compressible liquid chamber 52, with an incremental advancement being dependent upon the difference in volume of compressible liquid chamber 52 between its compressed and expanded state. Once compressible liquid chamber 52 is filled, compression thereof will begin to advance liquid toward dispensing tube 46 and ultimately the outlet 80 at the tip of spout 82. The advancement toward outlet 80 will also be incremental. After a number of repetitive compressions and expansions, the entire liquid path through dip tube 76 to outlet 80 will be filled with liquid product P, and each compression of compressible liquid chamber 52 will expel a dose of liquid product at outlet 80. Although dispenser 10 will have an air path completely filled with air upon construction, is should still be appreciated that the air, like liquid product P, will be advanced incrementally through dispenser 10 along its path under the compression of compressible air chamber 18. As already disclosed, as compressible air chamber expands, air will incrementally suck back through outlet 80 and reverse along is path toward the expanding volume of compressible air chamber 18. With this understanding, the paths for air and liquid toward outlet 80 are next disclosed.
Referring to
With reference to
Referring back to
Dual actuator 104 is moved against the bias force of biasing member 48 (and also compression delay element 110) to compress both compressible air chamber 18 and compressible liquid chamber 52. This advances doses of air and liquid through the dispenser 10 as already described, thus making foam at mixing chamber 98, exiting at outlet 80, through a stationary dispensing tube 46. Pressing down on dual actuator 104 presses down on flexible diaphragm 60, through compression delay element 110, thus compressing it and advancing liquid through dispenser 10, as described. Compression delay element 110 gives under the initial pressure and thus serves to delay the collapsing of flexible diaphragm 60 relative to the movement of piston 40. This causes a small amount of air to be moved before any liquid is advanced, and the air so moved will build up pressure due to the resistances to its movement through the small clearances throughout the air path and the resistance to movement of the air through inlet mesh 100. Thus, when liquid is moved upon adequate displacement of dual actuator 104 both the liquid and air enter mixing chamber 98 under pressure to create a high quality foam product. If the air path was not pre-pressurized prior to the liquid advancing then the foam product would be very wet at the beginning of dispense.
Upon the release of pressure pushing down on dual actuator 104, biasing member 48, flexible diaphragm 60, and compression delay element 110 all serve to aid the system in reverting back to its normal rest position. Compressible air chamber 18 and compressible liquid chamber 52 expand, with liquid being drawn up dip tube 76 into compressible liquid chamber 52, and air being drawn down from the outlet through mixing chamber 98 and annular air dispensing tube 96, ultimately back into compressible air chamber 18. This movement of air through the outlet back into the system can help prevent dripping at outlet 80.
It should be appreciated that the dispenser 10 shown in the drawings is particularly useful in a counter mounted environment, but the general structures and concepts disclosed herein could be applied to hand held dispensers and wall mounted dispensers. In a hand held embodiment, the dispenser 10 would simply be constructed with the structural elements disclosed for dispenser 10, with those elements constructed so as to produce a sleek external appearance and facilitate plunger actuation. In a wall mounted environment, the structural elements could again be readily adapted to fit within common wall mounted housings.
In a counter mount embodiment, cap 118 threads onto threaded neck 20 to press upper radial flange 22 against gasket 24, and thus helps to secure the mechanics of dispenser 10. A keyed overcap 130, also with a cut-out portion for elbow 86, fits over cap 118 and serves as a means for securing the combination container 12, associated compressible liquid and air chambers 52, 18, elbow 86 and dispensing tube 46 to bottle support 14, as described in copending US Published Patent Application No. 2007/0017932.
The counter mounted dispenser 10 is shown in
In an electronically activated system, plunger 200 would be replaced with a hands-free activation means, such as a sensor that, when tripped, activates electronic means to move gearing mechanisms to advance shaft 132 to compress the compressible air and liquid chambers 18, 52. The electronic means would also permit the shaft to cycle back to its rest position, thus putting the system in a state ready for a subsequent actuation.
In accordance with the foregoing, in particular embodiments of this invention, the product P is a liquid that is capable of foaming when mixed with air, and the product P is particularly chosen from a foamable skin care or skin sanitizing product. However, this invention is not limited to the dispensing of such products, particularly because it will be readily appreciated that the proposed dispensers herein could be employed for other products.
In light of the foregoing, it should thus be evident that the present invention provides a dispensing system that substantially improves the art. In accordance with the patent statutes, only the preferred embodiments of the present invention have been described in detail hereinabove, but this invention is not to be limited thereto or thereby. Rather, the scope of the invention shall include all modifications and variations that fall within the scope of the attached claims.
