Chemical product dispensing using a fluid drive and return home interface
A fluid-driven chemical product dispensing system dispenses fluid chemical product concentrates. The dispensing system includes a fluid drive unit powered by flow of a fluid, such as a diluent, and a pump which delivers the fluid chemical product concentrate from a supply to a destination. Upon exit from the fluid drive unit, the diluent is also delivered to the destination, where it mixes with the dispensed fluid chemical product concentrate to form a use solution. The dilution ratio of the volume of fluid chemical product concentrate dispensed per unit time versus the volume of diluent exiting the drive unit per unit time is constant over a defined range of diluent flow rates.
1. A dispensing system comprising:
a fluid drive unit including a housing having an inlet connected to receive a supply of a diluent such that flow of the diluent causes rotation of a rotor positioned within a cavity of the housing of the fluid drive unit, the housing further having an outlet from which the fluid exits the housing and is directed to a reservoir,
wherein a rotational speed (revolutions per minute) of the rotor as a function of flow rate of the diluent is substantially linear over a defined range of diluent flow rates;
a pump connected to receive a supply of a fluid chemical product concentrate, the pump further connected to be driven by the rotation of the fluid drive unit, resulting in dispensation of the fluid chemical product concentrate into the reservoir responsive to rotation of the fluid drive unit such that a dilution ratio of a volume of the fluid chemical product concentrate dispensed per unit time versus a volume of diluent exiting the fluid drive unit per unit time is constant over the defined range of diluent flow rates; and
a return home interface having an off position and a dispense position, the return home interface comprising:
a lobe rotor configured to interface with the pump such that the pump is stopped at a desirable rotational index when the return home interface is in the off position.
2. The dispensing system of claim 1 wherein the diluent is a liquid or a gas.
3. The dispensing system of claim 1 wherein the fluid drive unit comprises a turbine drive unit or a wheel drive unit.
4. The dispensing system of claim 1 wherein the diluent is water.
5. The dispensing system of claim 1 wherein the dilution ratio is in the range of 0.01 to 10 ounces per gallon.
6. The dispensing system of claim 1 wherein the rotor includes a drum having a plurality of blades disposed around a periphery of the drum, and wherein the blades have one of a flat shape, a scoop shape or a bucket shape.
7. The dispensing system of claim 1 wherein a concentration of the fluid chemical product in a use solution formed in the reservoir is constant over the defined range of diluent flow rates.
8. The dispensing system of claim 1 wherein the reservoir includes one of a container, a bucket, a pail, a bottle, a spray bottle, a sink, a sump, a non-rigid bag, a cleaning machine, a dish machine, or a laundry machine.
9. The dispensing system of claim 1 wherein the fluid chemical product concentrate includes at least one of a detergent, a rinse agent, a bleach, a fruit and vegetable wash, a disinfectant, or a sanitizer.
10. The dispensing system of claim 1 wherein the pump is a fixed volume displacement pump.
11. The dispensing system of claim 1 wherein the pump is one of a rotary pump, a gear pump, a screw pump, a piston pump, or a peristaltic pump.
12. The dispensing system of claim 1 wherein the pump further includes:
a circular housing having a continuous interior sidewall, the circular housing further including an inlet through which the fluid chemical product is received and an outlet through which the fluid chemical product concentrate is dispensed;
a pump lobe rotationally mounted within the circular housing, the lobe rotor including first and second opposed sides each forming a sealing surface with the interior sidewall, the lobe rotor further including third and fourth opposing sides each forming a cavity with the interior sidewall;
a flexible membrane having first and second ends each fixed to a different position on the interior sidewall and forming a sealing surface with the first or second opposed ends of the pump lobe as the pump lobe rotates within the housing.
13. The dispensing system of claim 12 wherein the lobe rotor of the return home interface is configured to interface with the pump such that the pump lobe is stopped at a rotational position within the housing in which the first and second ends are not in contact with the flexible membrane when the return home interface is in the off position.
14. The dispensing system of claim 12 wherein the lobe rotor of the return home interface is configured to interface with the pump such that the pump lobe freely rotates within the housing when the return home interface is in the dispense position.