JPH0229308B2 - KOOHIIMAMEBAISENSOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a roasting apparatus that can produce high quality roasted coffee beans.

[Prior Art and Problems] Generally, when roasting green coffee beans, various conditions must be set, such as the quality of the green beans themselves, the roasting method, and the ambient temperature and time during roasting. Among these, the heat source that generates the roasting temperature has a subtle influence on the quality.

Conventionally, roasting has been done using an open flame or high-temperature hot air as the heat source inside the furnace, but with the former method, it is difficult to control the roasting equipment, and only the outer surface of the roasted beans tends to burn. Not only will uneven roasting occur, but moisture and air bubbles inherent in the green coffee beans may interfere with the drying and heating of the green coffee beans, and impurities generated during roasting may mix with the green beans and impair the roasting process. There were drawbacks such as increased efficiency. In addition, although the latter method can give uniform temperature to the coffee beans, it also requires a large amount of hot air and a relatively long time, and the change in the composition of green coffee beans due to heating is not optimal. First, it had the disadvantage that it could only produce a tasty product, which tends to occur in mass production.

[Objectives of the Invention and Means for Solving the Problems] The present invention solves the above-mentioned conventional drawbacks, eliminates uneven roasting, and achieves uniform roasting with a unique aroma and aroma.
In addition to producing roasted coffee beans of very high quality that gives rise to flavor and brown color, moisture, air bubbles, and other impurities inside the green coffee beans are rapidly released and eliminated by air during the roasting process, and the above-mentioned The purpose is to improve the efficiency of the drying and heating effects using an infrared heater, and together with the increase in convection heat, achieve complete and uniform roasting in a short period of time. As well as forming a furnace body,
At the center of the interior of the furnace body, a generally cylindrical rotating drum with a large number of small holes bored in the peripheral wall is supported so as to rotate in a horizontal position, and an infrared heater is installed on the wall surface of the furnace body to surround the rotating drum. A blast pipe having an air outlet for jetting hot air is installed between the infrared heater and the rotating drum.

[Function] A current is passed through the infrared heater to raise the inside of the furnace to a predetermined temperature, and while the rotating drum is rotating at a low speed, an appropriate amount of green coffee beans is introduced into the rotating drum from the input gutter inserted into the rear wall. The green coffee beans are roasted by irradiating the green coffee beans with infrared rays over an appropriate amount of time from an infrared heater arranged so as to surround the rotating drum. At the same time, the hot air blowing out from the air pipes that surround the rotating drum rapidly evaporates and evaporates the moisture and air bubbles in the coffee beans, and also expels impurities, promoting the drying and heating effects of the infrared heater. .

[Example] In the figure, 1 indicates front/rear, upper/lower (hearth),
It is a furnace body in which the left and right side walls 2, 3, 4, 5, 6, and 7 are each formed into a box shape using a heat insulating material. The front side wall 2 has an opening 2 for taking out the roasted beans.
A is opened, an opening/closing door 2c is attached, and a charging gutter 9 is inserted into the rear wall 3 with its tip facing an opening of a rotating drum 8 to be described later. The hearth, which is the lower wall 5, is the second
As shown in the figure, an opening 5a is opened, and a pair of funnel-shaped guide plates 1 are provided at the front and back positions of the furnace body 1 at the bottom of the opening 5a.
Place 0a and 10b. The funnel-shaped guide plate 1
The bottom portions 0a and 10b are closed by providing a bottom portion 11, and a drawer 12 is placed on the bottom portion 11 so as to be able to be taken in and taken out to receive burnt skin scraps etc. that fall from the coffee beans during roasting. 13 is a support stand on which the furnace body 1 is placed, and 14 is an auxiliary stand on which the blower 15 and the drive motor 23 for rotating the drum are placed.

8 is a rotating drum installed in the center of the furnace body 1 to receive green coffee beans, and its front end surface 8
a is opened to face the opening 2a of the front side wall 2, and the rear end surface 8b is similarly opened, and the peripheral wall 16
It has a substantially cylindrical shape and has many small holes 17 formed therein. The center of the rotating drum 8 has a front end surface 8a to a rear end surface 8.
A shaft 19 is provided across the longitudinal direction of b, and the front wall 2 side of the shaft 19 passes through the front wall 2 and is rotatably supported by a bearing 20a, and the rear wall 3 side is rotatably supported by a bearing 20a. 3 and is rotatably supported by a bearing 20b. Further, a plurality of spiral plates 8c are provided to protrude from the inner surface of the peripheral wall so that the green coffee beans can be stirred well. A sprocket 21a is attached to the outside of the bearing 20b, one end of a chain 22 is suspended on the sprocket 21a, and the other end is connected to the motor 2 for driving the rotating drum 8.
It is suspended from a sprocket 21b provided at 3.
Further, the shaft rod 19 of the rotating drum 8 has the shaft rod 19
Beams 24 are fixed at two locations in a cross-sectional shape centering on the rotating drum 8.
The shaft rod 1 is integrally fixed to the inner circumferential surface 8a.
9 is supported within the rotating drum 8. 25, 25 are band-shaped annular frames fixed to the front side wall 2 and the rear side wall 3, respectively, and the front and rear end surfaces 8a, 8b of the rotating drum 8 are slidably inserted into the annular frames 25, 25. , closing the gaps between the end surfaces 8a, 8b and the front and rear side walls 2, 3. With this configuration, the rotating drum 8 is rotated in a horizontal position by the drive motor 23 interlocking the shaft 19 via the sprockets 21a and 21b. The rotating drum 8
The rotation speed is normally 48 to 50 rpm, and the speed can be changed.

Note that the rotating drum 8 is an infrared heater 2 to be described later.
In order to efficiently absorb the radiation heat from the rotating drum 8, the outer peripheral surface of the rotating drum 8 may be sintered with a ceramic enamel base material or a metal oxide having a high infrared absorption rate. Furthermore, the material of the rotating drum 8 is not limited to metal; an integrally molded ceramic material has high wear resistance and a long life, has a high infrared absorption rate, and is hygienic. Therefore, the coffee beans will not be contaminated.

An exhaust port 27 for removing smoke is provided in the upper wall 4 of the furnace body 1. Reference numeral 28 denotes a guide plate integrally laid on the lower surface of the opening 2a so that roasted coffee beans can be easily taken out from the rotating drum 8.

Thus, the upper wall 4 and the left and right side wall surfaces 6, 26 are arranged to surround the rotating drum 8 within the same plane at appropriate distances from the rotating drum 8, respectively.
A total of 18 infrared heaters are fixedly arranged along the longitudinal direction of the rotating drum 8 on the radiating surface 2.
9 are all directed toward the rotating drum 8. In this example, the infrared heater disclosed in Japanese Utility Model Publication No. 1983-3303 is used, which is an infrared heater in which an electric heating resistor such as nichrome wire is embedded inside a ceramic material such as a glazed ceramic board. Therefore, it is resistant to moisture, clean and sanitary, and has a large heat capacity that makes it difficult to cool down, so the temperature drop rate of the heater itself is slow, and the fluctuation range with respect to the set temperature is small, so it has the advantage of uniform heating. . Note that the ceramic plate may be curved or flat.

Note that since the lower part of the hearth 5 is a funnel-shaped opening 5a, heat dissipation increases from there, and the temperature of the atmosphere in the furnace near the lower part of the furnace body 1 decreases. In contrast, by making the watt density of the infrared heater 26 near the hearth 5 higher than the watt density of the other heaters 26, it is possible to prevent the temperature near the hearth 5 from becoming low and to uniformly heat the area.

Reference numeral 30 denotes conduits serving as blower pipes which are vertically piped in symmetrical positions so as to surround the rotating drum 8 inside the infrared heater 26, and a total of four pipes are provided, two each at two locations in the front and back inside the furnace body 1. . The four conduits 30 have branch pipes 3 connected orthogonally to the pipes 30.
1 are provided in appropriate numbers at symmetrical positions along the longitudinal direction, and air jet ports for jetting hot air toward the surface of the rotating drum 8 are opened at required intervals on each branch pipe 31. On the other hand, the four conduits 3
One end of each pipe 0 hangs down through the opening 5a of the hearth 5, and is connected to the front and rear of two conduits (not shown) piped along the longitudinal direction at the bottom of the furnace body 1 to form a connecting part, respectively. . Further, the connecting portion 32 on the rear side wall 3 side,
A conduit 34 is connected to each of the conduits 33, and the other end of the conduit 34 is connected to a blower 15 disposed on the right side of the furnace body 1.
, and an on-off valve 35 is provided in the middle thereof.

The present invention has the above-mentioned configuration. First, a current is applied to the infrared heaters 26 to raise the inside of the furnace body 1 to a predetermined temperature, and the blower 15 is driven to blow hot air toward the surface of the rotating drum 8. After that, the rotation drive motor 23 is driven to rotate the rotary drum 8, and an appropriate amount of green coffee beans are introduced into the rotary drum 8 from the input gutter 9, and the green coffee beans are roasted over an appropriate amount of time. . In this roasting process, the compressed air flow generated from the blower 15 passes through the air pipes 31 that are piped inside the furnace body 1, and air is emitted from the air injection ports provided in each air pipe 31. Since the hot air is blown onto the green coffee beans inside the rotating drum 8, moisture and air bubbles inside the green coffee beans are rapidly released and evaporated, and many of the small impurities are also discharged to the outside of the rotating drum 8. Ru. After roasting, the infrared heater 26
Stop the power supply and the drive motor 15 for blowing air,
On the other hand, the door 2c can be opened and closed while rotating the rotating drum 8.
is opened and the roasted coffee beans are taken out through a guide plate 28. Incidentally, it is preferable that the speed of the hot air from the air injection port is adjusted as appropriate by operating an on-off valve depending on the amount of green coffee beans to be processed.

In the present invention, compared to conventional open flame and hot air methods, radiant heat from the infrared heater 26 is transmitted from the surface layer of the coffee beans to the inside, and the coffee beans receive conductive heat from the rotating drum 8, which has high heat absorption. Since the rotating drum 8 is constantly rotating at a speed of 48 to 50 rpm, it receives convection heat evenly. Furthermore, the hot air from the air outlet gently blows the heated air onto the green coffee beans, which not only makes the convection heat more even, but also helps dry and heat the interior of the rotating drum 8 by eliminating moisture and impurities. encourage This, together with the rapid removal of the boundary heat film on the surface of the coffee beans, allows the coffee beans to be roasted in a short time. In this way, the same process is repeated to perform roasting.

[Effects of the Invention] As described above, the present invention roasts green coffee beans by rotating and stirring the coffee beans in a rotating drum while irradiating the green coffee beans with infrared rays from an infrared heater placed around the drum. Because of this, there are almost no areas that are shaded by the irradiation, and this combined with the effect that infrared rays are easily absorbed inside the heated object,
Each coffee bean is baked evenly inside and out, with almost no unevenness. Moreover, hot air is constantly blown onto the green coffee beans inside the rotating drum from the air outlet of the air pipe that surrounds the rotating drum. Moisture, air bubbles, and other impurities inside the beans are rapidly released and discharged, making the drying and heating effects of the infrared heater more efficient, making it possible to obtain very high-quality roasted coffee beans in a short time. Further, the blow pipe has a remarkable effect such as being able to prevent the impurities discharged from the inside of the rotating drum from falling on the infrared heater.

[Brief explanation of drawings]

FIG. 1 is a rear sectional view of the present invention, and FIG. 2 is a side sectional view. 1...Furnace body, 2...Front side wall, 3...Rear side wall, 4
...Upper wall, 5...Lower wall, 6...Left side wall, 7...
...Right side wall, 8... Rotating drum, 26... Infrared heater, 30, 34... Conduit.

Claims (1)

[Claims] 1. A furnace body is formed by a heat insulating wall, and a generally cylindrical rotating drum with a large number of small holes bored in the peripheral wall is supported approximately at the center of the inside of the furnace body so as to rotate in a horizontal position. An infrared heater is arranged on the wall surface of the furnace interior so as to surround the rotating drum, and a blower pipe having an air outlet for ejecting hot air is installed between the infrared heater and the rotating drum. Coffee bean roasting equipment.