JPH064862Y2 - Electric coffee kettle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an electric coffee brewing machine that changes a rotation mode of a motor according to the number of cups.

(Prior Art) A conventional electric coffee brewer has a crushing chamber having a cutter for crushing coffee beans in a main body case, a motor for rotating the cutter, a coffee basket for extracting coffee liquid, and a control means having a timer function. In addition, it has a mill net on the peripheral surface of the crushing chamber to guide the coffee powder crushed by the cutter to the coffee basket, and when crushing the coffee beans, put the coffee beans in the crushing chamber by a timer etc. The motor was energized at a constant duty ratio for a certain period of time, and coffee beans were crushed by a cutter that rotates in synchronization with the rotation of the motor.

(Problems to be solved by the invention) In the conventional electric coffee brewing machine, the motor is energized at a constant energization rate by a timer or the like. Since such a load is large and the load on the motor is also large, the rotation speed of the motor is low and the noise during grinding of coffee beans is low. However, with the passage of time, the coffee beans are crushed by the cutter, and become powder and move into the coffee basket through the mill net, and the load on the cutter gradually becomes lighter, so the number of rotations of the motor gradually rises and noise is increased. Has the drawback that it becomes large.
FIG. 6 is a graph of noise when the coffee beans are ground.
In addition, the number of cups (beans) required to change the rotation speed of the motor changed, and the energization time for powdering had to be changed.

(Means for Solving Problems) The present invention has been made in order to eliminate the above-mentioned drawbacks, and an operating section capable of inputting the number of cups into the main body case and a cup number input signal from this operating section are used to preset the number of cups. The control means is provided to change the time when the energization rate of the motor begins to decrease and the time when the energization of the motor is stopped according to the program set for the motor.

(Operation) In the present invention, the operation unit provided in the main body case acts to input the number of cups of coffee beans to be ground as a signal to the control means, and the control means provided in the main body case causes the number of cups to receive the signal. According to the above, the motor is rotated at a high duty ratio for a certain period of time during the initial period of energization, and the motor is rotated to a rotation speed that is sufficient to move the coffee powder into the coffee basket through the mill net after the coffee beans have been sufficiently ground and sanded. After stopping the rotation, the coffee powder is moved into the coffee basket, and then the motor is stopped.

(Embodiment) An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic structure of an electric coffee brewer according to the present invention. Reference numeral 1 is a main body case, 2 is a crushing chamber for storing coffee beans provided in the main body case 1, 3 is a cutter provided in the crushing chamber 2, 4 is a motor for rotating the cutter 3, and 5 is provided around the crushing chamber 2. Mill net 6 is a coffee basket provided next to the grinding chamber. Reference numeral 7 is a water container provided in the main body case 1 for containing water, 8 is a heater for heating the water in the water container 7, and 9 is a tapping arm for guiding the water heated by the heater 8 to the coffee basket 6. 10 is an operation part for operating the electric coffee brewer, 11 is a motor 4
And a heater 8 and the like.

FIG. 2 is a block circuit diagram of an electric coffee brewer according to the present invention. Reference numeral 12 denotes a temperature sensing unit for detecting the heat of the heater 8, which is a thermistor whose resistance value changes according to the heat of the heater 8. The temperature of the heater 8 is judged by inputting the change in the resistance value into the microcomputer 13,
When the heater 8 is cold, turn on the relay 14, and vice versa.
When the heater 8 is hot, the relay 14 is turned off. 15
Is a display unit for displaying the state of operation. Reference numeral 16 is a buzzer circuit. Reference numeral 17 denotes a temperature fuse, and when the heater 8 is abnormally heated, the temperature fuse 17 is melted by heat so that a circuit for energizing the heater 8 is opened, and the energization of the heater 8 is stopped. A thermostat 18 is attached to the heater 8 and is turned on depending on the temperature of the heater 8.
-Turn off and control the energization of the heater. Reference numeral 19 is a thyristor, which changes the energization rate of the motor 4 to 100%, N% or 0% according to a command from the microcomputer 13.
20 is a power supply.

FIG. 3 shows the control means 11 of the electric heater boiler according to the present invention.
Flowchart of program stored in the fourth
The figure is the same sequence diagram.

The operation of this embodiment having the above configuration will be described.

First, coffee beans are placed in the crushing chamber 2, and the operation unit 10 is operated to input the number of cups. When the start key is pressed (pressed) after inputting the number of cups, the program shown in Fig. 3 starts. For 1 cup, 2 cups, 3 cups, 4 cups, and 5 cups, the time (a, b, c, d, e) at which the duty factor of the motor 4 starts to decrease from 100%. ) Is different. The smaller the number of cups, the shorter the time when the number of cups starts to decrease, and the longer the time (f, g, h, i, j) at which the power supply to the motor 4 is stopped. That is, a <b <c <d <e <f <g <h <i <j. The relationship between the motor energization time and the motor energization rate according to this program is as shown in FIG. 4, and the change in the motor energization rate for one cup is as follows.

First of all, since there are many coffee beans in the grinding chamber at the initial stage of rotation, the motor load is so large that the motor has a duty factor of 100%. From the start of energizing the motor a
By the second, most of the coffee beans are ground. That is, most of the powder is coffee ground, and the rest is only moved through the mill net 5 into the coffee basket 6.

After a second has passed from the start of energization of the motor, the energization rate of the motor is reduced to N% and the coffee powder in the crushing chamber 2 moves through the mill net 5 into the coffee basket 6 (movement caused by rotation). It is designed to rotate up to the wind). For a while, the duty factor f
Hold up to seconds. During this time, all the coffee powder in the grinding chamber 2 moves into the coffee basket 6. After the lapse of f seconds, the energization rate to the motor 4 is set to 0% and the energization to the motor 4 is stopped. A graph of the idling sound of the motor 4 at this time is shown in FIG. In other words, since the time for starting to reduce the energization rate of the motor 4 is changed according to the number of cups, the coffee machine becomes a quiet electric coffee brewer in which coffee beans are not ground and the idling noise of the motor 4 does not increase.

(Effect of the Invention) In the present invention, the operation part that can input the number of cups into the main body case, the time when the motor energization rate starts to decrease and the time when the power supply to the motor is stopped by the cup number input signal of this operation part Since the control means for changing the number of cups is used, the idling noise of the motor after the coffee beans are crushed is quieted and the idling noise is shortened regardless of the number of cups.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a structural diagram of an electric coffee brewer showing an embodiment of the present invention, FIG. 2 is a block circuit diagram thereof, and FIG. 3 is a program stored in the control circuit. Flow chart of the
FIG. 4 is the same sequence diagram, FIG. 5 is a noise graph when crushing coffee beans, and FIG. 6 is a noise graph when crushing coffee beans in a conventional electric coffee brewer. 1 ... Main body case, 2 ... Grinding chamber, 3 ... Cutter, 4
...... Motor, 5 ...... Mill net, 6 ...... Coffee basket, 10 ...... Operation part, 11 ...... Control means.

Continued Front Page (72) Yutaka Sakai 1-2-7-11 Higashiueno, Taito-ku, Tokyo Eriko Suzuki, Examiner, Ishizaki Electric Works Ltd.

Claims (1)

[Scope of utility model registration request] 1. A crushing chamber (2) having a cutter (3) for crushing coffee beans in a main body case (1), a motor (4) for rotating the cutter (3), and a coffee basket (for extracting coffee liquid). In an electric coffee brewer having a mill net (5) on the peripheral surface of a crushing chamber (2) for guiding coffee ground crushed by a cutter (3) to a coffee basket (6), An operation part (10) that can input the number of cups in the case (1),
According to a program preset for the number of cups by the number-of-cups input signal of the operation unit (10), the time for decreasing the energization rate of the motor (4) from 100% to N% is changed, and thereafter, An electric coffee brewing machine comprising a control means (11) for changing the time for stopping the power supply to the motor (4).