Chemical dispensing system

• US 20030009428A1
• Filed: 07/17/2002
• Published: 01/09/2003
• Est. Priority Date: 10/24/2000
• Status: Active Grant

• Current Assignee: David J. Barbe
• Original Assignee: David J. Barbe
• Inventors: Barbe, David J.
• Granted Patent: US 6,669,052 B2
• Time in Patent Office: Days
• US Class Current: 705/413
• CPC Class Codes: D06F 2105/58 Indications or alarms to the control system or to the user
• CPC Class Codes: D06F 33/37 of metering of detergents or additives
• CPC Class Codes: D06F 39/022 in a liquid state D06F39/024 takes precedence
• CPC Class Codes: G06Q 50/06 Energy or water supply
• CPC Class Codes: Y10T 137/87249 Multiple inlet with multiple outlet

Abstract

A system for the operation of a number of commercial washing machines and automatically feeding liquid chemicals to the washing machines. The system has chemical reservoir pods with a pressure sensor and an output valve on each. The chemical pods are supplied with liquid chemical by refill pumps. The quantity of chemical in a chemical pod, and the quantity of chemical dispensed from each chemical pod is calculated from information received by a controller from the pressure sensor to determine when to open and close the valve. A further pressure sensor is provided in the supply pipe to each washing machine to verify and measure flow quantity of water and chemical to the machine.

Claims

1. A chemical dispensing system for supplying to one or more process units a plurality of liquid chemicals, the system comprising:

(a) a water supply;

(b) a supply pipe extending from the water supply at a first end to a second end thereof;

(c) a pump having an inlet port connected to the second end of the supply pipe and an outlet port connected to deliver liquid from the supply pipe to a selected process unit;

(d) a plurality of chemical pods individually connected to the supply pipe;

(e) a plurality of controllable valves, each one of which is connected between each of the chemical pods and the supply pipe; and

(f) one or more sensors, each one of which is connected to and adapted for transmitting a signal corresponding to the quantity of liquid chemical in each respective chemical pod.

2. The chemical dispensing system as claimed in claim 1, wherein the sensors comprise pressure sensors.

3. The chemical dispensing system as claimed in claim 1, wherein the sensors, the valves, the pump and the process unit are each connected to a controller that is programmed to control the operation thereof.

4. The chemical dispensing system as claimed in claim 1, further comprising a diverter valve connected intermediate the pump and each of the one or more process units so as to deliver liquid to a selected one of the process units while not delivering liquid to the other process units.

5. The chemical dispensing system as claimed in claim 1, wherein each of the chemical pods are of substantially equal height and differ in diameter according to the quantity of chemical to be stored.

6. The chemical dispensing system as claimed in claim 5, wherein the height of the chemical pods is as great as practical.

7. A method for dispensing a plurality of chemicals to a plurality of washing machines, wherein a supply pipe is connected from a water supply to the washing machines with a pump connected therebetween, a plurality of chemical pods are connected to the supply pipe with a plurality of valves between each pod and the supply pipe, and a plurality of sensors are connected to the chemical pods, wherein a controller is connected to and programmed to control the operation of the pump and the valves, and to receive signals from the sensors;

the method comprising;

(a) determining whether data exists at one of the washing machines to indicate a need for a quantity of one or more of the plurality of chemicals;

(b) determining from the chemical pod sensor signals whether each chemical pod in which the needed chemical is stored contains an adequate quantity of the needed chemical;

(c) if the chemical pod does not contain sufficient quantity of the chemical, activating an alarm;

(d) if the chemical pod contains sufficient quantity of the chemical, sending a signal from the controller to open one of the valves associated with the respective chemical pod so as to dispense the chemical; and

(e) determining from the sensor signals when the needed quantity of chemical remaining in the chemical pod indicates that the needed quantity of chemical has been delivered from the pod to the supply pipe and then closing the open valve.

8. The chemical dispensing system as claimed in claim 7, wherein determining when the needed quantity of chemical has been delivered comprises:

(a) storing in memory a factor for use in computing a volume of chemical in a chemical pod;

(b) sensing a first pressure of the chemical at a position adjacent a bottom of the chemical pod;

(c) computing a first volume of the chemical in the chemical pod from the first pressure and the factor;

(d) allowing the selected chemical to flow out from the chemical source;

(e) sensing a second pressure of the chemical at the position adjacent the bottom of the chemical pod;

(f) computing a second volume of the chemical in the chemical pod from the second pressure and the factor; and

(g) when the second volume differs from the first volume by a selected amount, stopping the flow of the chemical by closing the respective valve.

10. The method for calibrating the pressure sensor as described in claim 7, wherein the second selected level is adjacent the bottom of the chemical pod and the third selected level is adjacent the top of the chemical pod.

9. In a chemical dispensing system using at least one pressure sensor for determining a quantity of a liquid chemical in a chemical pod, a method for establishing a factor for calibrating the pressure sensor comprising:

(a) reducing the quantity of the liquid chemical in the chemical pod to a first selected level;

(b) sensing a first pressure of the liquid chemical at a second selected level, the second selected level being lower than the first selected level;

(c) increasing the quantity of the liquid chemical in the chemical pod to a third selected level;

(d) sensing a second pressure of the liquid chemical at the second selected level; and

(e) calculating the difference between the fist pressure and the second pressure divided by the chemical pod volume between the first selected level and the third selected level to establish a calibration factor.

11. In a chemical dispensing system having a single output pump and a plurality of diverter valves connected thereto for diverting flow of liquid to a selected one of a plurality of process units, a method for calibrating the flow quantity of liquid through a selected diverter valve comprising operating the output pump, opening the selected diverter valve, sensing the pressure adjacent the selected diverter valve, and storing the pressure sensed for use in calculating flow quantity of liquid.