This application is based on Japanese patent application No. 2003-318093 & 2003-318095 the content of which is incorporated hereinto by reference.
1. Field of the Invention
The present invention relates to a roaster for powder and granular material used for roasting powder of coffee bean, tea leaf, cereals and so forth.
2. Related Art
It is a general practice for manufactures of powders of coffee bean, tea leaf and so forth to roast a large amount of powder using a roaster for powder and granular material, because some kinds of the powders can add aroma and taste by being preliminarily roasted. A conventional roaster for powder and granular material will now be explained referring to, for example, a coffee bean roaster (simply referred to as a “roaster”, hereinafter) used for roasting coffee bean (or powder thereof). The roaster is roughly composed of a drum having on the top portion thereof an opening through which coffee beans (or powder thereof) are charged, a burner heating the drum from the lower side thereof, and a blade stirring the powder housed in the drum. As another example of the roaster, a tea leaf roaster used for roasting tea leaves (or powder thereof) is roughly composed of a horizontally disposed drum having on one end thereof a charging port through which the powder is charged into the drum, and having on the other end thereof a discharge section through which the roasted powder is discharged, a driving device rotating the drum, and a heating device heating the powder housed in the drum. Using these roasters, coffee beans and tea leaves (or powders thereof) are roasted by the burner and the heating device, wherein the coffee bean roaster discharges the roasted coffee beans again through the opening, and the tea leaf roaster discharges the roasted powder from the discharge section.
For ideal roasting, each powder preferably has a predetermined moisture content (for example, rice bran preferably has a moisture content of less than 2% or around), whereas in the above-described conventional roasters, the powder (of coffee beans, tea leaves or the like) is charged through the opening or charging port into the drum and housed therein, and is directly roasted without being adjusted to a predetermined moisture content (low moisture content), so that every grain of the powder is often roasted in black only on the surface thereof, rather than being well roasted to the core portion, only to give aroma and taste inferior to those reasonably required for the powder. In addition, the tea leaf roaster, upon being cooled by the external air, tends to cause dewing on the surface of the drum and the blade due to moisture emitted from the powder during the roasting, which may cause contamination.
The present invention was proposed in order to solve the problems in the above-described conventional roaster for powder and granular materials, aiming at providing a roaster for powder and granular material capable of efficiently roasting every grain of the powder to its core portion to thereby make the powder a high-quality one, and of effectively avoiding a risk of dewing, which is causative of contamination, even under cooling.
The present invention was proposed in order to solve the above-described problems, wherein the first invention (described in claim 1) provides a roaster for powder and granular material which include a charging port through which powder is charged; a drum housing the powder charged through the charging port; and a heating unit heating the powder housed in the drum; wherein a preheating chamber which preheats the powder charged through the charging port, and communicates with the drum, is provided between the charging port and the drum.
The second invention (described in claim 2) provides the roaster for powder and granular material described in the first invention, wherein the preheating chamber has a powder support member supporting the powder charged through the charging port, and having a large number of through-holes; a hot air supply unit supplying hot air from the lower side of the powder support member; and an exhaust unit discharging the air in the preheating chamber out into the external.
The third invention (described in claim 3) provides the roaster for powder and granular material described in the first or second invention, wherein the hot air supplied by the hot air supply unit to the preheating chamber is an air heated by a heating unit heating the powder housed in the drum.
The fourth invention (described in claim 4) provides the roaster for powder and granular material described in any of the first, second and third inventions, wherein the drum is supported by a plurality of rotating components in a rotative manner, all of or a part of the rotating components having a plurality of stepped portions formed thereon by which the drum is agitated.
The fifth invention (described in claim 5) provides the roaster for powder and granular material described in the fourth invention, wherein the drum has a flange portion on the outer circumference thereof, each of the rotating components has a groove allowing the flange portion to be inserted therein, and the stepped portion is formed either on the outer circumferential surface of the flange portion or on the ring-formed outer circumferential surfaces in the groove of the rotating components on which the flange portion inserted in the groove is rolled.
The sixth invention (described in claim 6) provides the roaster for powder and granular material described in the fourth or fifth invention, wherein the rotating components are configured by a first and a second rotating components disposed on one lower lateral side of the drum and coupled with each other through one coupling axis, and a third and fourth rotating components disposed on the other lower lateral side of the drum and coupled with each other through the other coupling axis in parallel with the one coupling axis, and the stepped portions are formed on both of the first and the second rotating components disposed ahead in the direction of movement of the powder housed in the drum caused by rotation thereof, or on both of the third and fourth rotating components.
In the first invention (described in claim 1), there is formed a preheating chamber, which preheats the powder charged through the charging port and communicates with the drum, between the charging port and the drum, so that it is made possible to lower moisture content of the powder in the preheating chamber, and thereby every grain of the powder passed through the preheating chamber is uniformly roasted to the core in an extremely effective manner in the drum, and to avoid a result that only the surface is scorched in black. Because the moisture content in the drum is kept low even when the roaster for powder and granular material is cooled, it is also made possible to sufficiently suppress the internal dewing, and to avoid a risk of causing contamination.
In the second invention (described in claim 2), the powder charged through the charging port and supported on the support member is heated by hot air coming through a large number of through-holes formed in the support member. In other words, the powder is heated by the hot air blowing upward from under the support member. The second invention can, therefore, preheat the powder in a costless and extremely efficient manner without using a special stirring device or driving device. Because the second invention is provided with the exhaust unit discharging the air in the preheating chamber, it is also made possible to keep a low moisture content not only in the drum but also in the preheating chamber even when the roaster for powder and granular material is cooled, and to further suppress the dewing inside the roaster for powder and granular material, and to avoid a risk of causing contamination in a more effective manner.
In the third invention (described in claim 3), the hot air supplied to the preheating chamber by the hot air supply unit is an air heated by a heating unit heating the powder housed in the drum, and is not a heating unit provided separately from that used for heating the powder housed in the drum, so that it is made possible to effectively use energy for heating, and to reduce the running cost as compared with the conventional roaster for powder and granular material.
In the fourth invention (described in claim 4), the drum is supported by a plurality of rotating components in a rotative manner, wherein all of, or a part of the rotating components have a plurality of stepped portions formed thereon by which the drum is agitated, so that every grain of the powder housed in the drum can uniformly be roasted over the entire surface with the aid of agitation of the drum. It is not always necessary for all of the rotating components to have the stepped portion formed thereon, and instead only a part of the rotating components may be configured as having the stepped portion by which the drum is agitated.
According to the fifth invention (described in claim 5), it is made possible not only to uniformly roast the powder while allowing the drum to roll as the rotating components rotate so as to agitate the drum, and thereby allowing the powder housed therein to agitate, but also to rotate the drum in an extremely stable and continuous manner without causing displacement of the drum due to agitation applied by the rotating components during the rotation of the drum, because the drum is supported by the rotating components as being inserted in the groove formed on the rotating components.
In the sixth invention (described in claim 6), the stepped portion is formed on both of the first and said second rotating components disposed ahead in the direction of movement of the powder housed in the drum caused by rotation thereof, or on both of the third and fourth rotating components, so that a portion of a powder moved from the position right under the center of the drum ahead in the direction of rotation releases from the inner circumferential surface of the drum under agitation caused by the stepped portion, and returns back to the position right under the center. In other words, according to the sixth invention, motion of the powder in the drum is just like a food (such as Chinese fried rice) cooked on a frying pan which is shaken by a cook over the fire so as to toss the food at the far end of the frying pan and to return it back to the cook's side. The sixth invention therefore makes it possible to roast every grain of the powder in a more uniform manner.
The above and other objects, advantages and features of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:
The invention will be now described herein with reference to illustrative embodiments. Those skilled in the art will recognize that many alternative embodiments can be accomplished using the teachings of the present invention and that the invention is not limited to the embodiments illustrated for explanatory purposes.
A roaster for powder and granular material according to the first embodiment of the present invention will be detailed below, referring to the attached drawings. The roaster for powder and granular material of this embodiment is one applied form of the present invention as a coffee bean roaster (simply referred to as a “roaster”, hereinafter) roasting mill-ground powder of coffee beans.
As shown in
Inside the roaster 1, there is provided the preheating chamber 3 so as to extend from the near-center of the roaster 1 towards the right side plate 1a side. The preheating chamber 3 is formed using a partition plate 9 partitioning the preheating chamber 3 from a later-described main heating chamber having a drum disposed therein; a front side partition plate 10 (see
On the side more closer to the front (this side) than the front of the front side partition plate 10, there is fixed a guide plate 13 guiding, in cooperation with the partition plate 10, the hot air to the lower side of the support plate 12. More specifically, a hot air passageway 14 guiding the hot air to the lower side of the support plate 12, which is composed of the front side partition plate 10 and the guide plate 13, is formed on the front side of the preheating chamber 3. Inside the roaster 1 and above the preheating chamber 3, there is provided a dust collector 20 as shown in
On the left side of the portion of placement of the preheating chamber 3, there is formed a main heating chamber 29 while placing the partition plate 9 in between, and a drum 30 is disposed in the main heating chamber 29. The drum 30 is molded as a laterally-elongated cylinder as shown in
At a position slightly lower than the center of the drum 30, there is disposed a rotary shaft 40 in the horizontal direction as shown in
As shown in
To the main heating chamber 29 having the drum 30 disposed therein, as shown in
Operations of the above-described roaster 1 of this embodiment will be described below. The coffee beans charged through the charging port 2 with the aid of pneumatic transportation pass through the cylinder 5 and the metal attachment 6 to reach the preheating chamber 3, and supported on the support plate 12. The hot air flows into the preheating chamber 3 (in a blown-up manner) from the lower side of the support plate 12, after passing through a large number of through-holes formed in the support plate 12. The coffee beans in the preheating chamber 3, under heating and drying by the hot air, are then thrown through the opening 9a formed in the partition plate 9 into the drum 30 rotating in the main heating chamber 29. The coffee beans thrown into the drum 30 are stirred by rotation of the drum 30 and the rotation of the first to fourth beater 41 to 44, and at the same time, gradually moved towards the left side of the roaster 1, while being tossed up and down over a short range in the drum 30 which rolls with the aid of the first and the second rotating components 31, 32, while being vibrated on the plurality of stepped portions formed thereon. More specifically, when the first to fourth rotating components 31, 32, 35 and 36 rotate counter-clockwisely, for example, the drum 30 rotates clockwisely with the aid of these first to fourth rotating components 31, 32, 35 and 36, as shown in
As described in the above, the roaster 1 of this embodiment preheats and dries the coffee beans in the preheating chamber 3, before roasting them in the drum 30 disposed in the main heating chamber 29, and can effectively roast the coffee beans as the powder to the cores in the drum 30, so that it is made possible to provide coffee beans of an extra-high quality. In particular, the preheating in the roaster 1 is effected by the hot air blown upward from the lower side of the support plate 12, so that there is no fear of causing non-uniform preheating. Because the moisture content in the drum 30 is kept low even when the roaster 1 is cooled by virtue of such preheating in the preheating chamber 3, it is also made possible to sufficiently suppress the dewing in the roaster 1, and to effectively avoid a risk of causing contamination. In particular, because the air in the preheating chamber 3 is discharged to the external with the aid of the ventilating fan 23, the roaster 1 can suppress the contamination in a more effective manner.
Because the air supplied to the preheating chamber 3 is an air heated by the gas burner 49 in the main heating chamber 29, energy of the gas burner 49 can effectively be used, demonstrating a large energy-saving effect. Again because the auxiliary heater 61 is disposed midway of the route along which the hot air in the main heating chamber 29 is supplied to the preheating chamber 3, it is allowable to activate the auxiliary heater 61 when the temperature of the hot air to be supplied to the preheating chamber 3 is low, due to use in the wintertime, or in cold regions.
In particular in the roaster 1 of this embodiment, as described in the above, the stepped portions composing the present invention are formed only on the first and the second rotating components 31, 32 disposed on one side of the drum 30 (the rotating components disposed ahead in the direction of movement of the powder (coffee beans P) in the drum 30 under rotation), and are not formed on the third and the fourth rotating component 35, 36 disposed on the opposite side, so that motion of the coffee beans P housed in the drum 30 is just like a food (such as Chinese fried rice) cooked on a frying pan which is shaken by a cook over the fire so as to toss the food at the far end of the frying pan and to return it back to the cook's side. The roaster 1 can therefore heat every grain of coffee beans in a more uniform manner over the entire surface thereof.
While the roaster 1 of this embodiment described in the above is such as used for roasting the coffee beans P as the powder, the roaster for powder and granular material of the present invention is, of course, not limited to those roasting the coffee beans P, allowing those used for roasting any powder composed of tea leaf, rice bran or various cereals. The roaster 1 described in the above uses the gas burner as the heating unit composing the present invention, whereas any other heating units such as electric heater can be used so far as they can roast the powder housed in the drum.
It is apparent that the present invention is not limited to the above embodiments, that may be modified and changed without departing from the scope and spirit of the invention.
Number | Date | Country | Kind |
---|---|---|---|
2003-318093 | Sep 2003 | JP | national |
2003-318095 | Sep 2003 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/JP04/12622 | 9/1/2004 | WO | 3/9/2006 |