Automatic dispenser

Abstract

An automatic dispenser that is operated by pressure conveying a fluid from a reservoir. The system includes a reservoir having an inlet and an outlet. A pump is disposed in fluid communication with the reservoir. A first conduit is in fluid communication with the inlet to the reservoir and the pump. A second conduit is in fluid communication with the outlet of the reservoir. While the reservoir is being pressurized, a valve in the second conduit is closed. After the reservoir is pressurized, the valve is opened and the fluid in the reservoir is conveyed through the second conduit. The fluid is typically gravity fed from the second conduit to a fixture such as a urinal or toilet.

Description

FIELD OF INVENTION

The present invention relates to automatic liquid dispensers.

BACKGROUND OF THE INVENTION

Automatic liquid dispensers are used in many applications. One example is the dispensing of cleaning detergents into bathroom fixtures. Typically, a self-contained unit having a reservoir for storage of the liquid and having a battery operated pump is used. A common type of dispenser utilizes a piston-type pump to draw liquid from the reservoir into a conveying tube. There are some significant drawbacks related to these type of dispensers. Piston-type pumps are prone to losing prime which renders the pump inoperative. Also, the amount of liquid that is drawn from the reservoir will vary depending on the level of the liquid in the reservoir. When the reservoir is full there is less suction required to dispense the liquid, whereas when the reservoir is low it is more difficult to pull the liquid from the reservoir. What is needed is an inexpensive, automatic dispenser that dispenses a consistent quantity of liquid and is more reliable than the piston-type pumps.

SUMMARY OF THE INVENTION

The present invention meets the above-described need by providing an automatic dispenser that operates by pressure conveying the fluid out of the reservoir. The automatic dispenser includes an air pump in fluid communication with an inlet to the reservoir. A normally closed valve prevents the liquid from exiting the pressurized reservoir until a valve is opened.

The system operates as follows. On a predetermined, periodic basis, an air pump is activated. The air pump outlet is in fluid communication with the reservoir. The pump pressurizes the reservoir for a predetermined time period. Next, a valve is opened for a short period of time and liquid is conveyed from the reservoir into a conduit leading from the reservoir to the outlet of the automatic dispenser. From the outlet of the automatic dispenser to the fixture, the liquid may be conveyed by gravity.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is illustrated in the drawings in which like reference characters designate the same or similar parts throughout the figures of which:

FIG. 1 is a perspective view of a typical application for the automatic dispenser of the present invention;

FIG. 2 is a plan view of the components of the present invention with the electrical wiring removed for clarity;

FIG. 3 is a schematic diagram of the automatic dispenser of the present invention; and;

FIG. 4 is an alternate embodiment of the present invention.

DETAILED DESCRIPTION

Referring to FIG. 1, a typical application for the automatic dispenser 10 of the present invention is for dispensing liquid cleaning detergents through a conduit 11 to a fixture 13 such as a toilet or urinal. As shown, the liquid detergents are typically gravity fed from the outlet of the dispenser 10 to the fixture 13. The dispenser 10 dispenses the liquids automatically on a predetermined, periodic basis as will be described in greater detail below.

Although the dispenser 10 of the present invention is being described in connection with dispensing liquid cleaning detergents to fixture 13, the invention is not intended to be limited to that particular application. As will be described below, the dispenser 10 of the present invention also may have application for dispensing hostile fluids in other applications.

Turning to FIGS. 2 and 3, a reservoir 16 having a bottom wall 17, side walls 18 and a top wall 19 stores a liquid 20 which may comprise a cleaning detergent. The reservoir 16 may be constructed of any suitable plastic or other material as will be evident to those of ordinary skill in the art. The reservoir 16 may be disposable or may be capable of being refilled for multiple uses. The reservoir 16 also has an inlet 22 and an outlet 25.

An air pump 28 operated by an electric motor 31 is arranged such that the outlet 34 of the air pump 28 is placed in fluid communication with the inlet 22 to the reservoir 16 by means of conduit 37. Although the invention is described in connection with an air pump other gases may also be suitable and for certain applications inert gases such as nitrogen may be required. The conduit 37 may comprise plastic tubing or other suitable materials as will be evident to those of ordinary skill in the art.

At the outlet 25 of the reservoir 16, a conduit 40 is arranged such that the pick-up end 43 is disposed inside the reservoir 16. As shown the pick-up end 43 may be extended toward the bottom wall 17. For some liquids that tend to stratify, it is advantageous to extend the pick-up end 43 toward the bottom wall 17.

The conduit 40 extends through the outlet 25 of the reservoir 16 to a pinch valve 50. The pinch valve 50 is normally closed and operates by deforming the walls of the conduit 40 inward until the passageway through the conduit is closed off. As will be evident to those of ordinary skill in the art, the flexibility of the conduit 40 and the force of the valve 50 on the walls of the conduit 40 are adjusted such that the flow through the conduit 40 can be opened and closed repeatedly without causing leakage or mechanical failure of the conduit 40. Although the pinch valve 50 is shown in the figure, any type of normally-closed, automatic valve suitable for use with a relatively small conduit may be substituted. The conduit 40 extends downstream of the valve 50 to the outlet 63.

In operation, a controller 60 (FIG. 3) activates the air pump 28 at a predetermined, periodic time period. The air pump 28 pressurizes the reservoir 16 for a predetermined period of time. Because the reservoir 16 is pressurized in this manner, the level or amount of liquid 20 contained in the reservoir 16 does not affect the quantity of fluid to be conveyed unless the reservoir is near empty and does not contain at least one charge of liquid. This feature is in contrast to the piston-type pumps which can lose prime and which convey different amounts of liquid depending on the amount or level of the liquid 20 contained in the reservoir 16. Also, the viscosity of the liquid 20 is not critical with the dispenser 10 of the present invention. In contrast, for the piston-type pump, the viscosity of the liquid 20 is a significant factor.

After a predetermined period of time with the air pump 28 operating, the valve 50 is opened for a short period of time (typically less than one second) to allow a charge of liquid 20 to exit through conduit 40. Conduit 40 leads to outlet 63 on the bottom side of the dispenser 10.

Turning to FIG. 3, a power supply 66 provides power to the controller 60. The power supply 66 may comprise batteries but other power supplies may also be suitable as will be evident to those of ordinary skill in the art. As described above, the controller 60 activates the air pump 28 on a periodic basis. The controller also activates the valve 50 at a predetermined time period after the activation of the pump 28.

The present invention offer several advantages including the fact that there is no direct contact between the liquid 20 and any of the electromechanical components of the system. Accordingly, there is no issue with contamination of the pump or the valve and no need for seals or O-rings. This feature may be even more significant in applications where the liquid 20 comprises a hostile fluid.

Also, the pressure-conveying system of the present invention is not affected by small leaks in the line because the pump 28 is capable of operating at a rate sufficient to overcome any pressure loss due to small leaks.

Another advantage of the system is the ability of the system to mix liquids that are susceptible to stratifying. For example, biocides have a tendency to separate such that the active organisms become concentrated toward the bottom. Because of the pressurization of the reservoir 16 and the location of the pick-up end 43 toward the bottom wall 17, a more homogeneous mixture of the liquid 20 is conveyed than would be possible with a piston-type pump.

In an alternate embodiment shown in FIG. 4, the pump 28 is eliminated from the system. In the alternate embodiment, the fluid is conveyed from the reservoir via gravity. Reservoir 100 is positioned an outlet 103 at the bottom such that liquid 106 can by conveyed by gravity into conduit 109. The flow of liquid is controlled by a pinch valve 112.

While the invention has been described in connection with certain embodiments, it is not intended to limit the scope of the invention to the particular forms set forth, but, on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.

Claims

1. An automatic dispenser system, comprising: a reservoir having an inlet, an outlet, and a bottom wall, the reservoir capable of holding a supply of a liquid; a pump disposed in fluid communication with the inlet of the reservoir via a first conduit, the pump capable of pressurizing the reservoir; a second conduit having an inlet and an outlet, the inlet disposed in fluid communication with the outlet of the reservoir; a valve disposed in operative relation to the second conduit; a controller capable of controlling the pump and the valve; and, a power supply capable of supplying power to the controller; wherein the pump pressurizes the reservoir for a predetermined period of time until the valve is opened such that liquid is conveyed by pressure through the second conduit to the outlet of the second conduit.

2. The automatic liquid dispenser system of claim 1, wherein the valve is normally closed.

3. The automatic liquid dispenser system of claim 1, wherein the valve is a pinch valve disposed external to the second conduit.

4. The automatic liquid dispenser system of claim 1, wherein the second conduit has a pick-up section disposed in proximity to the bottom wall of the reservoir.

4. The automatic liquid dispenser system of claim 1, wherein the second conduit has a pick-up section disposed in proximity to the bottom wall of the reservoir.

5. The automatic liquid dispenser system of claim 1, wherein the controller operates the pump on a periodic predetermined basis to pressurize the reservoir.

6. The automatic liquid dispenser system of claim 1, further comprising a fixture gravity fed by the outlet of the second conduit.

7. The automatic liquid dispenser system of claim 6, wherein the fixture is a urinal.

8. The automatic liquid dispenser system of claim 6, wherein the fixture is a toilet.

9. An automatic dispenser system for use with a bathroom fixture such as a toilet or urinal, the system comprising: a reservoir having an inlet, an outlet, and a bottom wall, the reservoir capable of holding a supply of fluid; a pump disposed in fluid communication with the inlet of the reservoir and capable of pressurizing the reservoir; a normally closed valve disposed in operative relation to the second conduit, the valve capable of mechanically shutting off flow through the conduit without coming into contact with the fluid; a controller capable of operating the pump on a predetermined periodic basis and capable of opening the valve after the reservoir is pressurized such that fluid is conveyed through the second conduit to the fixture; and, a power supply capable of supplying electrical power to the controller.

10. The automatic dispenser system of claim 9, wherein the liquid is gravity fed from the second conduit to the fixture.

11. The automatic dispenser system of claim 9, wherein the valve is a pinch valve disposed external the second conduit.

12. The automatic dispenser system of claim 9, wherein the second conduit has a pick-up section disposed near the bottom wall of the reservoir.

13. The automatic dispenser system of claim 9, further comprising a check valve between the pump and reservoir.

14. The automatic dispenser system of claim 13, wherein the fluid in the reservoir only contracts the reservoir and the second conduit.

15. A method of automatically dispensing a fluid, the method comprising: providing a supply of a fluid in a reservoir having an inlet and an outlet; providing a pump in fluid communication with the inlet of the reservoir, the pump capable of pressurizing the reservoir; providing a first conduit between the pump and the inlet of the reservoir; providing a second conduit in fluid communication with the outlet of the reservoir pressurizing the reservoir containing the fluid by means of the pump; providing a valve in operative relation with the second conduit; and, opening the valve to allow the fluid to pass from the outlet of the reservoir through the second conduit.

16. The method of claim 15, wherein the fluid only contacts the reservoir and the second conduit.

17. The method of claim 15, wherein the valve is a pinch valve disposed external to the second conduit.

18. The method of claim 15, wherein the pump is actuated periodically at predetermined intervals.

19. The method of claim 15, wherein the pump pressurizes the reservoir with air.

20. The method of claim 15, wherein the pump pressurizes the reservoir with nitrogen with an inert gas.