JPH07148071A - Siphon type coffee extractor - Google Patents

Abstract

PURPOSE:To quickly detect the boiling start in a lower vessel by directly detecting the heat of the steam, when the water in the lower vessel is boiled, and its steam flows into an upper vessel, by a boiling detecting means. CONSTITUTION:When the water in a lower vessel 6 is boiled, and the hot water starts to rise in a water passing tube 10, the steam of the hot water rises into an upper vessel 7 and makes contact with a thermosensitive plate 18, and the heat of the steam is detected by a thermal reed switch 19. When the temperature of the thermal reed switch 19 reaches a preset fixed temperature, its contact is opened to release the excitation of a relay, whereby the relay contact is opened to stop the current carrying to a heater 4 and a pilot lamp 32. Although the thermal reed switch is low in precision of temperature detection, compared with a thermistor, it directly detects the heat of the steam in the upper vessel 7, and can quickly detect the start of boiling in the lower vessel 6 even when the temperature detecting precision is low. Therefore, the extracting time of coffee is never prolonged, and coffee of mellow flavor can be extracted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a siphon coffee extractor for extracting coffee using a lower container and an upper container.

[0002]

2. Description of the Related Art A siphon-type coffee extractor comprises an extractor body having a heater, a lower glass container for storing water, and an upper glass container for containing coffee powder. ing. The upper container is detachably arranged on the lower container, and a water pipe extends from the bottom of the upper container to a lower portion thereof, and the water pipe is inserted into the lower container.

When extracting coffee, a predetermined amount of water is contained in the lower container, a filter is arranged on the inner bottom of the upper container, and a predetermined amount of coffee powder is contained on the filter. In this state, the water in the lower container is heated through the heater incorporated in the extractor body.

Along with this heating, the water in the lower container becomes hot water and boils, and the boiling fills the lower container with steam, and the vapor pressure causes the hot water in the lower container to rise in the water pipe. Then, it flows into the upper container through the filter, and the hot water extracts coffee in the upper container.

When all of the hot water in the lower container flows into the upper container, the pressure in the lower container decreases, and the decrease in pressure causes the coffee in the upper container to flow out through the water pipe into the lower container as a drop. Be stored.

The extractor body is provided with a thermistor (temperature sensor) as a boiling detection means. The thermistor is arranged so as to come into contact with the outer surface of the upper container, the water in the lower container boils, and hot water is heated in the upper container. When the temperature of the upper container rises and the temperature of the upper container rises, the heat is detected to determine the start of boiling, and the energization of the heater is cut off based on this determination. The hot water in the lower container continues to boil due to the residual heat of the heater, so that the entire amount of the hot water in the lower container flows into the upper container through the water pipe.

[0007]

As described above, in the prior art, when hot water flows into the upper container and the temperature of the wall surface of the upper container rises, the heat is detected to judge the start of boiling. There is. However, even if the hot water flows into the upper container, the temperature of the wall surface of the upper container does not rise rapidly, so that the boiling detection is delayed and the timing of turning off the heater is delayed. If the timing of turning off the power to the heater is delayed, the high pressure state in the lower container will be maintained for a while even after the entire amount of the hot water in the lower container has flowed into the upper container. The storage time of the hot water is extended, and the time during which the coffee grounds are immersed in the hot water, that is, the coffee extraction time is prolonged. When the extraction time of coffee is prolonged, components such as tannic acid are excessively produced in the coffee, resulting in coffee with a strong bitterness and astringency, and a mellow flavor cannot be obtained.

If a thermistor having a high detection accuracy is used as the temperature sensor, the delay of boiling detection can be compensated by the high accuracy, but an inexpensive thermal reed switch (T
If RS) is used as a temperature sensor, its detection accuracy is low, so that boiling detection is delayed, the extraction time of coffee is prolonged, and it becomes difficult to extract mellow-flavored coffee.

The present invention has been made paying attention to such a point, and an object thereof is to promptly detect the start of boiling in the lower container without using a temperature sensor having a particularly high detection accuracy. Another object of the present invention is to provide a siphon-type coffee extractor that can properly maintain the coffee extraction time.

[0010]

In order to achieve such an object, the present invention has an upper container arranged on a lower container, and a water pipe extending below the upper container is formed at the bottom of the upper container. , The water pipe is inserted into the lower container, the water contained in the lower container is heated by a heater to boil, and the boiling water causes the hot water in the lower container to flow into the upper container through the water pipe to make coffee. In the siphon-type coffee extractor for extracting, when the water in the lower container is boiled and the steam flows into the upper container, a boiling detection means for detecting the steam and shutting off the energization of the heater is provided. It is the one.

[0011]

When extracting coffee, a predetermined amount of water is contained in the lower container, and a predetermined amount of coffee powder is contained in the upper container. When the start switch is turned on under this condition, the heater is energized, the water in the lower container is heated by this heater, and with this heating, the water in the lower container becomes hot water and eventually boils. The lower container is filled with steam by boiling, and the hot water in the lower container gradually rises in the water pipe due to this vapor pressure and gradually flows into the upper container.The hot water dips the coffee powder in the upper container. Coffee is extracted.

When the water in the lower container boils and the hot water begins to rise in the water pipe, the steam of the hot water rises in the upper container, and this steam is detected by the boiling detection means, and in response to this detection. The heater is turned off.

After the heater is de-energized, the boiling water in the lower container continues due to the residual heat of the heater, whereby the entire amount of the hot water in the lower container flows into the upper container through the water pipe.

After all of the hot water in the lower container has flowed into the upper container, the pressure in the lower container decreases, and the coffee extracted in the upper container passes through the water pipes in the lower container due to the decrease in pressure. The coffee is stored in the lower container.

As described above, the boiling detection means directly detects the heat of the steam in the upper container, and therefore, even if the temperature detection accuracy of itself is low, the start of boiling in the lower container can be quickly detected. To turn off the power to the heater,
Therefore, coffee extraction time is not prolonged, and coffee with a mild flavor can be extracted.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Reference numeral 1 shown in FIG. 1 is an extractor main body, and the extractor main body 1 is composed of a base portion 2 and an upright portion 3 which is erected upward from one end portion of the base portion 2.
A heating unit 5 having a built-in heater 4 is provided on the upper surface thereof.

A lower container 6 made of glass is arranged on the heating part 5, and an upper container 7 made of glass is arranged on the lower container 6. An opening 8 having a relatively small diameter is formed at the upper end of the lower container 6, and an opening 9 having a relatively large diameter is formed at the upper end of the upper container 7. A water pipe 10 extends from the bottom of the upper container 7 to the lower side thereof.
Are inserted in the lower container 6. When extracting coffee, the filter 11 is attached to the inner bottom of the upper container 7. Reference numeral 12 is a handle attached to the lower container 6.

A lid 14 is provided on the upper end of the upright portion 3 via a hinge pin 15 so as to be vertically rotatable. As shown in FIG. 2, on the lower surface of the lid body 14, a convex portion 16 that slightly protrudes in a stepwise manner is formed below the lid body 14, and the convex portion 16 is rotated in response to the rotation of the lid body 14 to form the upper container 7. It is configured to fit inside the opening 9 at the upper end of the with a proper play.

A circular opening 17 is formed in the center of the convex portion 16, and a circular plate-shaped metal heat-sensitive plate 18 is mounted in the opening 17, and the inner bottom of the heat-sensitive plate 18 is mounted. Thermal reed switch (TR
S) 19 is provided. A metal holding plate 20 is provided on the upper side of the heat sensitive plate 18, and the holding plate 20 is a screw 2
The thermal reed switch 19 is elastically pressed by the pressing plate 20 so that the thermal reed switch 19 is fixed so as to be in close contact with the heat sensitive plate 18.

A detection switch 25 composed of a micro switch is provided inside the lid 14, and a detection lever 26 is provided adjacent to the detection switch 25. The detection lever 26 has a hinge pin 2 at its proximal end.
7, and is rotatably supported in the vertical direction via the hinge pin 27. Then, the tip end side of the detection lever 26 extends outward from the lower surface of the lid body 14,
Under the condition in which is closed in the opening 9 of the upper container 7, the end portion on the extending side comes into contact with the edge of the opening 9 of the upper container 7.

An operation piece 28 is integrally formed on the base end of the detection lever 26 so as to stand upright, and the operation piece 28 is an actuator 25a of the detection switch 25.
It is placed opposite to. When the edge of the opening 9 of the upper container 7 is in contact with the tip of the detection lever 26 and the tip of the detection lever 26 is pushed upward, the operation piece 28 is the actuator of the detection switch 25. Two
5a is elastically pressed, and the detection switch 2 is pressed by this pressing.
When the contact point 5 is closed and the detection lever 26 pivots downward with the hinge pin 27 as a fulcrum under its own weight from this state, the operation piece 28 is displaced toward the end edge side of the actuator 25a, and this displacement causes the detection switch 25 to move. The contacts are designed to open.

An operating portion 30 is provided on the side surface of the standing portion 3 of the extractor body 1, and a start switch 31 and a pilot lamp 32 are arranged on the operating portion 30. An electric circuit is shown in FIG. 5, in which a heater 4, a thermal reed switch 19, and a pilot lamp 32 are connected in parallel to a power source 35, and a relay 36 is connected to the thermal reed switch 19. A relay contact 36a interlocking with the relay 36 and a detection switch 25 are connected in series to one terminal side of the power source 35, and a start switch 31 is connected in parallel to the relay contact 36a. Reference numeral 37 is a thermal fuse provided on the other terminal side of the power supply 35.

Next, the operation will be described. When extracting coffee, a predetermined amount of water is stored in the lower container 6, a filter 11 is attached to the inner bottom of the upper container 7, and a predetermined amount of coffee powder is stored in the upper container 7. Then, the lower container 6 is placed on the heating part 5 of the extractor main body 1 in a state where the upper container 7 is superposed on the lower container 6, and the lid 14 is rotated to move the lid 14 to the upper container. 7 and the opening 9 is closed. Depending on the closing of the lid 14, the detection lever 2
The tip end of 6 contacts the edge of the opening 9 of the upper container 7, and this operation closes the detection switch 25.

Under this condition, the start switch 31 is turned on. In response to this input, the relay 36 is excited, the relay contact 36a is closed, and the heater 4, the thermal reed switch 19, and the pilot lamp 32 are energized via the relay contact 36.

Then, the water in the lower container 6 is heated by the heater 4, and with this heating, the water in the lower container 6 becomes high-temperature hot water and eventually boils. By this boiling, the lower container 6 is filled with steam. Due to this vapor pressure, the hot water in the lower container 6 gradually rises in the water pipe 10 and sequentially flows into the upper container 7 through the filter 11. The hot water soaks the coffee powder in the upper container 7 and Extraction is performed.

When the water in the lower vessel 6 boils and the hot water begins to rise in the water pipe 10, the steam of the hot water rises in the upper vessel 7 and contacts the heat-sensitive plate 18, so that the heat of this steam is generated. Is detected by the thermal reed switch 19. Then, when the temperature of the thermal reed switch 19 reaches a preset constant temperature, the contact is opened, and by this opening, the excitation of the relay 36 is released, and by this release, the relay contact 36a is opened, and the heater 4 and Pilot lamp 32
De-energized. The thermal reed switch 19 may detect steam, and the contact of the thermal reed switch 19 may be opened after a predetermined time has elapsed from the detection.

In this way, the hot water in the lower container 6 is passed through the water pipe 1
When starting to rise in 0, the heater 4 is de-energized, but the hot water in the lower container 6 continues to boil due to the residual heat of the heater 4. Then, all the hot water in the lower container 6 flows into the upper container 7 through the water pipe 10.

After the whole amount of the hot water in the lower container 6 flows into the upper container 7, the pressure in the lower container 6 decreases, and the coffee extracted in the upper container 7 is passed through the water pipe by the decrease in the pressure. The coffee flows through the lower container 6 through the head 10 and is stored in the lower container 6.

The thermal reed switch 19 as a temperature sensor has a lower temperature detection accuracy than a thermistor, but the thermal reed switch 19 directly detects the heat of the vapor in the upper container 7, and therefore the thermal reed switch is used. Even if the temperature detection accuracy of the switch 19 itself is low,
The start of boiling in the lower container 6 can be quickly detected. For this reason, it is possible to extract coffee with a mild flavor without prolonging the coffee extraction time.

By the way, when the water in the lower container 6 is being heated by the heater 4, the lower container 6 and the upper container 7 may be removed from above the heating unit 5, or the lid 14 may be rotated upward. In this case, the detection lever 26 pivots outwards on the lower surface side of the lid 14 by its own weight around the hinge pin 27 as a fulcrum, and this pivotal movement opens the detection switch 25, which energizes the heater 4. It is cut and safety is ensured.

[0031]

As described above, according to the present invention,
Since the boiling started is judged by directly detecting the steam that has flowed into the upper container from the lower container, it is possible to quickly start the boiling in the lower container without using a temperature sensor with high detection accuracy. There is an advantage that it is possible to extract a mellow-flavored coffee by detecting it and appropriately maintaining the coffee extraction time.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view of a siphon coffee extractor according to an embodiment of the present invention.

FIG. 2 is a sectional view of a portion of a lid of the coffee extractor.

FIG. 3 is a cross-sectional view showing a state when the lid of the coffee extractor is opened.

FIG. 4 is a plan view of a mounting portion of a thermal reed switch in the coffee extractor.

FIG. 5 is an electric circuit diagram of the coffee extractor.

[Explanation of symbols]

 4 ... Heater 6 ... Lower container 7 ... Upper container 14 ... Lid 19 ... Thermal reed switch (boiling detection means)

Claims (5)

[Claims] 1. An upper container is arranged on a lower container, and a water pipe extending downward is formed at the bottom of the upper container. The water pipe is inserted into the lower container and accommodated in the lower container. In a siphon-type coffee extractor in which the heated water is boiled by heating it with a heater and the boiling water flows into the upper container through the water pipe to extract coffee, the water in the lower container boils. Then, when the steam flows into the upper container, a siphon-type coffee extractor is provided, which is provided with boiling detection means for detecting the steam and shutting off the energization of the heater. 2. The siphon-type coffee extractor according to claim 1, wherein the boiling detection means detects the steam and shuts off the energization of the heater when a certain temperature is reached. 3. The siphon-type coffee extractor according to claim 1, wherein the boiling detection means detects the steam and shuts off the energization of the heater when a predetermined time has elapsed. 4. The siphon coffee extractor according to claim 1, wherein the boiling detection means is provided on a lid which opens and closes an opening at the upper end of the upper container. 5. The siphon coffee extractor according to claim 1, 2, 3 or 4, wherein the boiling detection means is a thermal reed switch.