Automatic coffee brewing apparatus and control method

• US 7,571,674 B2
• Filed: 08/22/2005
• Issued: 08/11/2009
• Est. Priority Date: 01/19/2005
• Status: Expired due to Fees

• Current Assignee: Toptechnology Co., Ltd.
• Original Assignee: Toptechnology Co., Ltd.
• Inventors: Wang, Dong-lei
• Primary Examiner(s): ALEXANDER, REGINALD
• Application Number:
  US11/208,796
• Publication Number:
  US 20060156928A1
• Time in Patent Office: 1,450 Days
• Field of Search: 993/02.P, 993/02.R, 992/80, 992/95, 992/89.R
• US Class Current: 99/302.00P
• CPC Class Codes: A47J 31/3609 Loose coffee being employed
• CPC Class Codes: A47J 31/3614 Means to perform transfer from a loading position to an infusing position
• CPC Class Codes: A47J 31/60 Cleaning devices

Abstract

This invention provides for a coffee brewing apparatus and its control method, which comprises a control circuit and a water loop comprising a water reservoir, a pump, a control valve, a boiler, a brewing assembly, a three-way connector and a connecting hose. When coffee is to be brewed, hot water flows top-down through the brewing chamber cover, the upper filter, the coffee grounds, the lower filter, the brewing chamber, the first port of the three-way connector, the second port of the three-way connector and the connecting hose; the brewed coffee finally flows out from said connecting hose. This coffee brewing apparatus has additional functions of automatic residue discharge, automatic water discharge and automatic cleaning.

Claims

1. An automatic coffee brewing apparatus, comprising:

a control circuit;

a water loop including;

a water reservoir, a pump, a control valve, a boiler, a brewing assembly, a three-way connector having a first, a second and a third port and a connecting hose;

wherein said brewing assembly includes a brewing chamber cover, a brewing chamber, an upper filter and a lower filter, wherein said upper filter and lower filter are disposed inside said brewing chamber, and wherein coffee grounds are accommodated between said upper filter and lower filter when coffee is to be brewed;

wherein said lower filter, brewing chamber and three-way connector constitute the brewing core, and wherein said brewing core is rotatable about a pivot axis, so that the brewing chamber can assume one of a brewing position and a position for receiving coffee grounds;

wherein in the brewing position, the brewing chamber cover is closed on the brewing chamber, and the coffee grounds are accommodated and compacted between the upper filter and the lower filter;

while in the position for receiving coffee grounds, the brewing chamber cover is separated from the brewing chamber, and the lower filter is positioned at the bottom inside the brewing chamber;

wherein said brewing chamber has a chamber outlet at its bottom, which is connected with the first port of said three-way connector;

wherein a second port of said three-way connector is connected with one end of said connecting hose, wherein a plunger assembly is installed for opening and closing the third port of said three-way connector;

said plunger assembly of the three-way connector comprising a drain actuator stem, a drain gasket, a drain plunger stem connected with the bottom of the drain gasket, and a compression spring installed above the drain gasket, wherein one end of the drain actuator stem is fixed on the pivot axis of the brewing core, and can be rotated about said pivot axis, wherein the drain actuator stem can be rotated to the position where it pushes the drain plunger stem to drive the drain gasket upwards to compress the compression spring, so that the third port of the three-way connector is opened, wherein the drain actuator stem can be rotated to a position where it separates from the drain plunger stem, wherein the drain gasket is pushed downwards under the resilient force of the compression spring, so that the third port of the three-way connector is closed;

wherein another end of said connecting hose is connected to a through hole on the brewing chamber cover opening to a coffee outlet;

wherein, when coffee is to be brewed;

a) coffee grounds are accommodated between the upper and lower filters,

b) the third port of said three-way connector is closed,

c) hot water flows top-down through the brewing chamber cover, the upper filter, the coffee grounds, the lower filter, the brewing chamber, the first port of the three-way connector, the second port of the three-way connector and the connecting hose;

d) the brewed coffee finally flows through said connecting hose out of the coffee outlet; and

,

after the brewed coffee has flowed out, the third port of the three-way connector is opened under the control of the control circuit, wherein waste water remaining in the brewing chamber is discharged from the third port of the three-way connector through the lower filter, the brewing chamber and the first port of the three-way connector.

2. A coffee brewing apparatus according to claim 1, wherein a connecting rod is connected to the bottom of the lower filter, and a through hole is provided at the bottom of the brewing chamber, so that, said connecting rod passes said through hole and is connected with the pivot axis of the brewing core, wherein under the control of the control circuit, said connecting rod is capable of driving the lower filter to move up and down the brewing chamber, and wherein in a residue discharge position, the lower filter arrives at the top of the brewing chamber, and wherein a sealing ring is disposed at the inner periphery of the through hole at the bottom of the brewing chamber, so as to prevent the coffee grounds and water from flowing out through the gap at the periphery of the through hole.

3. A coffee brewing apparatus according to claim 1, wherein said control circuit comprises a MCU, a pump control circuit, a control valve control circuit, a brewing core control circuit and a plurality of position sensors;

wherein said pump control circuit for controlling the operation of the pump comprises a motor M1 and a thyristor circuit T1, wherein one end of the motor M1 is connected to MCU via the thyristor circuit T1;

wherein said control valve control circuit for controlling the operation of the control valve comprises a motor M2 and a thyristor circuit T2, wherein one end of the motor M2 is connected to MCU via the thyristor circuit T2;

wherein said brewing core control circuit for controlling the rotational position of the brewing core comprises a motor M3 and a thyristor circuit T3, wherein one end of the motor M3 is connected to MCU via the thyristor circuit T3;

wherein the plurality of position sensors is used for sensing the position of the brewing chamber during its movement;

said position sensors are connected to different input ports of MCU respectively.

4. A coffee brewing apparatus according to claim 3, wherein at least one jet nozzle connected with said pump through the control valve is provided around said brewing core, wherein a water-proof cover is further provided covering the brewing core and the at least one jet nozzle;

in addition, a drain pan is provided, wherein said water-proof cover has a water collecting outlet opening to said drain pan.

5. A control method for controlling the coffee brewing apparatus defined in claim 2, comprising the following steps:

after the brewed coffee has flowed out, under the control of the control circuit, the brewing core is rotated about the pivot axis, so that the brewing chamber is separated from the brewing chamber cover;

then the connecting rod connected at the bottom of the lower filter, moves the lower filter inside the brewing chamber to the residue discharge position so as to discharge the residues automatically;

under the control of the control circuit, the brewing core continues to be rotated toward the position for receiving coffee grounds, and the third port of the three-way connector is opened;

before the brewing chamber is returned to the position for receiving coffee grounds, under the control of the connecting rod connected to the bottom of the lower filter, the lower filter undergoes a quick return motion from the residue discharge position to the bottom inside the brewing chamber, which generates an impact to cause the waste water remaining in the brewing chamber under the filter to flush the filter, such that the waste water is discharged automatically and the filter is cleaned automatically.

6. The control method of the coffee brewing apparatus according to claim 4, further comprising the steps of cleaning an interior of the brewing core, said steps including:

rotating the brewing core without coffee grounds under the control of the control circuit;

injecting hot water into the brewing chamber when the brewing core is rotated to the brewing position;

rotating the brewing core about the pivot axis, so as to separate the brewing chamber from the brewing chamber cover;

under the control of the connecting rod connected to the bottom of the lower filter, moving the lower filter inside the brewing chamber to the residue discharge position so as to discharge the residues automatically;

wherein under the control of the control circuit, the brewing core continues to be rotated toward the position for receiving coffee grounds, and the third port of the three-way connector is opened, wherein before the brewing chamber is returned to the position for receiving coffee grounds, under the control of the connecting rod connected to the bottom of the lower filter, the lower filter undergoes a quick return motion from the residue discharge position to the bottom inside the brewing chamber, suitable for generating an impact to cause the waste water remaining in the brewing chamber under the filter to flush the filter, such that the waste water is discharged automatically and the filter is cleaned automatically.

7. A control method for controlling the coffee brewing apparatus defined in claim 4, comprising the following steps:

initiating cleaning of one of an interior and an exterior of the brewing core in dependence upon a user'"'"'s input to the MCU;

if interior cleaning is to be performed, motor M2 begins to work under the control of the MCU via thyristor circuit T2, and a water channel towards the boiler is opened by the control valve;

then, motor M3 begins to work under the control of the MCU via thyristor circuit T3, and the brewing core without coffee grounds is rotated;

when the brewing core is rotated to the brewing position, the MCU receives a signal sent out by the position sensor, and motor M1 begins to work under the control of the MCU via thyristor circuit T1, so that water is pumped from the water reservoir and hot water is injected into the brewing chamber via the brewing chamber cover;

then, the procedures for interior cleaning are started under the programmed control;

when the interior cleaning procedures are finished, returning to a main control program;

if the exterior cleaning is to be performed, motor M1 begins to work under the control of the MCU via thyristor circuit T1, and water is pumped from the water reservoir;

then, motor M2 begins to work under the control of the MCU via thyristor circuit T2;

water is channeled to the at least one jet nozzle via the control valve, and water is ejected through the at least one jet nozzle, so as to realize the exterior cleaning of the brewing core.

8. The control method of the coffee brewing apparatus according to claim 7, wherein, more than one jet nozzles connected with said pump through the control valve are provided at different positions around said brewing core;

when the exterior cleaning is to be performed, the thyristor circuit T3, under the control of MCU, drives motor M3 to rotate the brewing core;

the MCU receives signals sent out by the position sensors, so as to control the operation of motor M2 according to different positions of the moving brewing chamber, and cause the jet nozzles at different positions to spray at different time intervals.

9. An automatic coffee brewing apparatus, comprising:

a control circuit;

a water loop including;

a water reservoir, a pump, a control valve, a boiler, a brewing assembly, a three-way connector having a first, a second and a third port and a connecting hose;

wherein said brewing assembly includes a brewing chamber cover, a brewing chamber, an upper filter and a lower filter, wherein said upper filter and lower filter are disposed inside said brewing chamber, and wherein coffee grounds are accommodated between said upper filter and lower filter when coffee is to be brewed;

wherein said brewing chamber has a chamber outlet at its bottom, which is connected with the first port of said three-way connector;

wherein a second port of said three-way connector is connected with one end of said connecting hose, wherein a plunger assembly is installed for opening and closing at the third port of said three-way connector;

wherein another end of said connecting hose is connected to a through hole on the brewing chamber cover opening to a coffee outlet;

at least one jet nozzle connected with said pump through the control valve, which is provided around a brewing core comprising said lower filter, brewing chamber and three-way connector;

a drain pan; and

a waterproof cover covering all the jet nozzles, wherein said waterproof cover has a water collecting outlet opening to said drain pan.

10. A control method for controlling the coffee brewing apparatus defined in claim 9, comprising the following step:

spraying with the at least one jet nozzle installed around the brewing core under the control of the control circuit, so as to clean an exterior of the brewing core.