JPS6343620A - Coffee maker - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a coffee maker for extracting coffee.

2. Description of the Related Art A conventional coffee maker having a structure as shown in FIG. 3 is known. Here, 101 is a commercial power supply, 10
2 is a power switch, 103 is a heater that heats water, 10
4 is a thermostat installed near the heater 103. When the user presses the power switch 102, the commercial power supply 101 is supplied to the heater 103 through the thermostat 104.
is applied, and the heater 103 generates heat. Here, the thermostat 104 has a characteristic of turning OFF at temperatures above 130°C and turning ON at temperatures below 130°C. Water is heated by the heater 103 and coffee is extracted. When the water runs out, the temperature of the heater 103 rises, so the thermostat 104 is turned off.
The heater 103 then stops generating heat, thereby completing the coffee extraction.

After the extraction is completed, the temperature of the heater 103 is maintained at about 30° C. by the thermostat 104, and the extracted coffee liquid is kept warm.

Problem to be Solved by the Invention However, with this configuration, if the user uses the coffee maker for the purpose of heating water rather than brewing coffee, and the water is added to the water before it runs out, the heater 103 Because the temperature keeps rising, the thermostat 104
As a result, the heater 103 is continuously energized, and the temperature of each part of the coffee maker rises due to the heat of the heater 103, which tends to cause problems with the lifespan and reliability of the parts used. Had to use hot parts.

The object of the present invention is to provide a coffee maker that solves these problems.

Means for Solving the Problems In order to solve the above problems, the coffee maker of the present invention controls the energization of the heater when the temperature of the temperature sensing element does not reach a predetermined temperature even after heating the heater for a certain period of time. The switching means is provided with a control signal that outputs a constant ON-FF signal.

Effect According to the above configuration, when the heater is heated for a certain period of time, the heater is heated intermittently after that, so the temperature of the heater does not become high for a long time, and as a result, the temperature of the coffee maker increases. This will improve the lifespan and reliability of the parts used.

Embodiment Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings.

In FIGS. 1 and 2, 10 is a heater that heats water;
Reference numeral 20 denotes switching means for controlling energization of the heater 10, which includes relay contacts 21. Relay coil 22, transistor 2
3. It is composed of a resistor 24. 30 is a thermistor, and this thermistor 30 corresponds to a temperature sensing element. 40 is a temperature detection means for determining whether the temperature of the thermistor 30 is higher than a predetermined temperature, and includes a comparator 41. It is composed of resistors 42, 43 and 44. 6Q is a control means that inputs the output signal of the temperature detection means 40 and outputs a control signal to the switching means 2o; 60 is a constant voltage power supply;
1, 62, a diode 63, a capacitor 64, and a constant voltage diode 66. Reference numeral 70 denotes a start means, which is composed of a resistor 71 and a start switch 72. 76 is a commercial power source, 81 is a water tank,
82 is a check valve that regulates the flow of water; 83 is a pipe that guides the water in the tank 81 to the heater 1; 84 is a watering unit that reduces the force of water discharged from the pipe 83; and 86 is a basket that stores coffee grounds. , 86 is a lid attached to the upper surface of the basket 86, 87 is a glass container into which extracted coffee liquid is placed, and 88 is a discharge port.

The operation of the above configuration will now be described.

The power supply for the dwarf 6 is rectified by a resistor 61 and a diode 63, smoothed by a capacitor 64, and connected to a resistor 62. The voltage is made constant by the constant voltage diode 65, and the temperature detection means 40. It serves as a power source for the control means 5Q. When the user fills water in the tank 81, opens the MB2, puts coffee grounds into the pasta throat 86, and closes the lid 86, the setting is completed. At this point, the water in the tank 81 is
2 and is led to pipe 83. User presses switch 7
When 2 is pressed, part a changes from HIGH to LOW, and this signal is input to the control means 6o.

With this signal, the control means 60 changes the switching means 20 to ○N.
Output a signal. This signal is applied to the pace electrode of the transistor 23 via the resistor 24, turning on the transistor 23, energizing the relay coil 22, and relay contact 21.
closes. As a result, the AC voltage of the commercial power supply 75 is applied to the heater 10 . Then, the water in the pipe 83 is heated by the heater 10 and boils to generate steam. The pressure inside the vibrator 83 increases due to the generated steam, but due to the function of the check valve, the boiled water does not flow into the water tank, but instead is spouted from the upper part of the pipe 83 to the sprinkler lid 84. When the boiling water is ejected, the pressure inside the pipe 83 decreases, and the water is led from the tank 81 to the pipe 83 again, becoming boiling water and ejected to the sprinkler lid 84. The coffee powder stored in the duster 86 is poured and the extracted coffee liquid is stored in a glass container 87 through a hole at the bottom of the basket 86. On the other hand, when the water in the tank 81 runs out, water is no longer guided to the pipe 83, so the temperature of the heater 10 increases and the resistance value of the thermistor 30 attached near the heater 10 decreases. Here, if the resistance values of the resistors 42, 43, and 44 of the temperature detection means 40 are set to the optimum values, the resistance value of the thermistor 30 is large when there is water in the tank 81, so the combination
The output of the comparator 41 is HIGH, but when the water runs out and the temperature of the heater 1o rises, the resistance value of the thermistor 30 decreases, and when the thermistor 30 exceeds a predetermined temperature, the output of the comparator 41 becomes LOW.

Due to this change in the output of the temperature detection means 40, the control means 50
outputs an OFF signal to the switching means 2o, and as a result, the heater 10 stops generating heat, and the extraction of coffee liquid is completed.

However, when the water in the tank 81 decreases for the purpose of boiling water, etc., and water is added as a result of this decrease, water is continuously led to the pipe 83, so the heater 10 Continuously energized. In this case, the thermistor 30 does not reach the predetermined temperature even after a certain period of time (a time set slightly longer than the time for the thermistor 30 to reach the predetermined temperature when water is not added) has elapsed, so the control means 60 causes the switching means 2o to 4 seconds ON, 4 seconds OFF /7) O
Outputs N-OFF signal. When water is no longer added and water is no longer introduced to the vibrator 83, the temperature of the thermistor 30 rises, as described above, and the heater 10 stops generating heat.

Effects of the Invention As described above, according to the present invention, even if the user uses the coffee maker for a purpose other than brewing coffee, such as boiling water, and water is added before the water in the tank runs out, After the heater has been energized continuously for a certain period of time, the heater is energized intermittently by ON-0FF control, which suppresses the temperature rise of the heater, and as a result, lowers the upper limit temperature of the heater and other parts used. It is extremely practical, as it lowers the temperature, improves reliability, and lowers the heat resistance of the parts used, resulting in a reduction in material costs.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of a coffee maker showing an embodiment of the present invention, Fig. 2 is a partial sectional view of the same coffee maker, and Fig.
The figure is a circuit diagram of a conventional coffee maker. 10... Heater, 20... Switching means, 30... Temperature sensing element, 40... Temperature detection means, 60... Control means. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 1O---(-ta 2O---Z<j+Ngena role 30- plexus)

Claims (1)

[Claims] A heater that heats water, a switching device that controls energization of the heater, a temperature sensing element installed near the heater, and a temperature detection device that determines whether the temperature of the temperature sensing element is equal to or higher than a predetermined temperature. The output signal of the temperature detection means is input, and the switching means is operated for a certain period of time.
A coffee maker comprising a control means for outputting an ON-OFF signal of a constant period to a switching means when the temperature of a temperature sensing element does not reach a predetermined temperature even after outputting an N signal.