초록 ▼

A beverage dispenser and method of operation, in which incoming water for beverage preparation is heated by a liquid-to-liquid heat exchanger. The heated water may be mixed with cold water using controlled valves, to generate a selected temperature stream. This controlled-temperature stream may be m

A beverage dispenser and method of operation, in which incoming water for beverage preparation is heated by a liquid-to-liquid heat exchanger. The heated water may be mixed with cold water using controlled valves, to generate a selected temperature stream. This controlled-temperature stream may be mixed with beverage concentrate or sprayed over coffee grounds to brew fresh coffee.

대표청구항 ▼

What is claimed is: 1. A beverage dispenser comprising: a) a controller, comprising: i) at least one control signal output ii) at least one sensor input; iii) a user input interface; iv) control logic coupled to the at least one control signal output, the at least one sensor input and the user inpu

What is claimed is: 1. A beverage dispenser comprising: a) a controller, comprising: i) at least one control signal output ii) at least one sensor input; iii) a user input interface; iv) control logic coupled to the at least one control signal output, the at least one sensor input and the user input interface, such that the control logic controls at least one control signal output in response to user input at the user input interface; b) a source of circulating hot liquid; c) a water input coupled to a pressurized water supply; d) a liquid-to-liquid heat exchanger having an input coupled to the water input, an output for heated water, and a heat-exchange circuit through which the circulating hot liquid from the source of circulating hot liquid circulates, such that water from the input is heated by exchange with the hot liquid, and the water exits from the output of the heat exchanger at an elevated temperature; e) a hot valve having an input coupled to the output of the heat exchanger, a control input for controlling flow through the valve in response to a signal from a control output of the controller, and an output for dispensing hot water under control of the control input; and f) a beverage dispensing output coupled to the output of the hot valve, such that the water flows through the dispenser under pressure, from the pressurized water supply through the heat exchanger and the hot valve under control of the controller, and is dispensed by the beverage dispensing output, without being held in storage. 2. The beverage dispenser of claim 1, further comprising: a) a cold valve having an input coupled to the water input, a control input for controlling flow through the valve in response to a signal from a control output of the controller and an output for dispensing cold water under control of the control input; b) a temperature mixing junction coupled to the output of the hot valve and the output of the cold valve, for mixing the hot water and cold water into a mixed water stream coupled to the beverage dispensing output; and c) a temperature sensor sensing the temperature of the mixed water stream, having an output coupled to a sensor input of the controller; the control logic of the reading the temperature of the mixed water stream from the sensor input coupled to the temperature sensor, and the controller issuing signals on the control output coupled to the control input of the hot valve and on the control output coupled to the control input of the cold valve, such that the stream of mixed water is maintained at a selected temperature. 3. The beverage dispenser of claim 2, in which control signals sent to the hot valve and the cold valve are pulse-width modulated, such that the flow through each valve is controlled by varying a duty cycle of the pulse-width modulated signals. 4. The beverage dispenser of claim 2, further comprising at least one dispensing section comprising: a) a reservoir of beverage concentrate having an outlet; b) a pump having an input coupled to the output of the reservoir outlet, an output, and a control input coupled to a control output of the controller, such that a signal on the control input causes the pump to pump a defined amount of beverage concentrate from the pump output; c) a section water input coupled to the temperature mixing junction, for accepting the mixed water stream at the defined temperature; d) a beverage mixing junction in which the beverage concentrate and the mixed water stream are mixed, having inputs coupled to the section water input and the pump output, and an output coupled to the beverage dispensing output; and e) a flow sensor sensing water flow in the water input, coupled to a sensor input of the controller; the control logic of the controller reading the water flow from the flow sensor and operating the pump to mix a selected amount of beverage concentrate with the water, such that the beverage dispensing output of the beverage dispenser dispenses beverages of a selected concentration and temperature. 5. The beverage dispenser of claim 4, further comprising a beverage valve in the mixed stream of water, between the temperature mixing junction and the beverage mixing junction, having a control input coupled to a control output of the controller such that quantity of the mixed water stream into the beverage mixing junction is controlled by the controller through a signal on the control input of the beverage valve. 6. The beverage dispenser of claim 4, further comprising a) a washing junction having a first input coupled to the beverage concentrate reservoir through a first check valve, a second input, and an output coupled to the dispensing output; b) a supply of washing fluid, comprising: i) a reservoir of detergent; ii) a detergent pump having an input coupled to the reservoir of detergent, and an output; iii) a wash water valve having an input coupled to the water input of the dispenser, a control input coupled to a control output of the controller, and an output; iv) a wash liquid mixing junction having an input coupled to the output of the detergent pump, an input coupled to the output of the wash water valve, and an output for diluted detergent coupled to the second input of the washing junction through a second check valve, the second check valve having an opening pressure much higher than an opening pressure of the first check valve; such that when the wash water valve is opened and the detergent pump is operated, a quantity of diluted detergent is sent from the wash liquid mixing junction through the washing junction, and the dispensing output of the beverage dispenser. 7. The beverage dispenser of claim 6, further comprising a drain valve coupled to the wash liquid mixing junction, for draining diluted detergent remaining in the wash liquid mixing junction. 8. The dispenser of claim 4, in which the pump is a positive displacement pump. 9. The dispenser of claim 8, in which the positive displacement pump is a peristaltic pump. 10. The dispenser of claim 8, in which the positive displacement pump comprises a moving part formed as part of the reservoir, and a solenoid for operating the moving part mounted to the dispenser. 11. The dispenser of claim 10, in which the moving part is a piston. 12. The dispenser of claim 10, in which the moving part is an outer part of a flexible chamber. 13. The beverage dispenser of claim 2, further comprising: a) a pressurizable enclosure; b) a holding basket for coffee grounds, pressure sealed to the enclosure, having an outlet at a bottom of the basket coupled to the beverage dispensing output of the beverage dispenser; c) a spraying head inside the enclosure, coupled to the temperature mixing junction, located above the basket, such that the mixed water stream from the temperature mixing junction is sprayed onto the grounds in the holding basket, such that coffee is extracted from the grounds and dispensed through the bottom of the basket at the selected temperature. 14. The beverage dispenser of claim 13, further comprising a grounds temperature sensor located in the holding basket for measuring the temperature of the coffee grounds, having an output coupled to a sensor input of the controller. 15. The beverage dispenser of claim 14, in which control logic of the controller operates the hot valve and the cold valve to inject hot and cold water alternately in short pulses until brewing is completed. 16. The beverage dispenser of claim 14, in which control logic of the controller operates the hot valve and the cold valve to vary the temperature of the mixed water stream as a function of time. 17. The beverage dispenser of claim 13, further comprising a coffee grinder having a control input coupled to a control output of the controller. 18. The beverage dispenser of claim 1, further comprising: a) a pressurizable enclosure; b) a holding basket for coffee grounds, pressure sealed to the enclosure, having an outlet at a bottom of the basket coupled to the beverage dispensing output of the beverage dispenser; c) a spraying head inside the enclosure, coupled to output of the hot valve, located above the basket, such that the hot water from the hot valve is sprayed onto the grounds in the holding basket, and coffee is extracted from the grounds and dispensed through the bottom of the basket. 19. The beverage dispenser of claim 18, further comprising: a) a steam valve having an input coupled to the output of the heat exchanger and an output; b) a steam chamber having a steam output, a spray head coupled to the output of the steam valve, and a heated evaporating plate located in the chamber such that water from the spray head sprayed on the evaporating plate flashes into steam and leaves under pressure through the steam output. 20. The beverage dispenser of claim 1, further comprising a pressure regulator between the water supply and the water input. 21. The beverage dispenser of claim 1, in which the source of circulating hot liquid is located remotely. 22. The beverage dispenser of claim 1, in which the source of circulating hot liquid comprises a heater, a reservoir for storing hot liquid, and a circulating pump for pumping liquid through the reservoir, the heater and the heat exchanger. 23. The beverage dispenser of claim 1, further comprising a dispensing valve lever adjacent to the beverage dispensing output and coupled to a sensor input of the controller, such that the controller logic begins dispensing beverage in response to operation of the dispensing valve lever. 24. The beverage dispenser of claim 1, in which the operator interface comprises a touch-screen. 25. The beverage dispenser of claim 4, in which the temperature sensor is positioned adjacent to the beverage dispensing output, so that it measures the temperature of the mixed water stream after mixing with the beverage concentrate.