JPS6161027B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD This invention relates to a grain storage tank that also serves as a grain husk dryer. Conventional technology When storing grains, especially raw paddy, it is necessary to ventilate the stored grains, but in conventional grain storage tanks, as shown in Japanese Utility Model Publication No. 44-10289, ventilation is required from the bottom of the tank. Ventilation was directed upwards. However, since grains are stored in tanks with a large thickness from the top and bottom, large wind pressure is required for ventilation, and since this ventilation only occurs in one direction, the air inlet area and the air There was a large difference in the humidity of the air at the outlet, and ventilation with uniform humidity could not be achieved. In addition, there is a grain dryer that dries the grains in a drying chamber to a uniform moisture content by alternately blowing air through the left and right walls of the grains in the drying chamber, as shown in Japanese Utility Model Application Publication No. 50-71454. However, since this type allows air to flow from a flat surface, a very large grain pressure is applied to the air jetting area, so it was necessary to strengthen that area, and a special reinforcing device was required for this purpose. In order to eliminate this drawback, the present inventor first provided four or more tubes having a large number of ventilation holes at equal intervals on the inner surface of the circumferential wall of the tank body, which consists of a circumferential wall and a bottom wall, and these tubes. A grain dryer in which each of the pipes is connected to a high pressure source and a low pressure source, and when one of the pipes is connected to the high pressure source, the other is sequentially connected to the low pressure source, and the high pressure source is sequentially connected to the pipe body. Patent application No. 53-5842 (Japanese Patent Application No. 105049-1983) for a storage tank.
Publication No. 2). However, in the grain dryer/storage tank provided earlier, when the pipes are sequentially connected to a low pressure source, it is necessary to partially reverse the rotation, so the intake rotary valve must be reversed, and this makes the control difficult. It has the disadvantage of being complicated and increasing costs. Problems to be Solved by the Invention The present invention eliminates the above-mentioned drawbacks, makes it possible to uniformly moisten grains with small wind pressure, and does not require a special reinforcing device at the wind jetting part, and does not require a rotary valve. It is an object of the present invention to provide a grain dryer/storage tank that can easily and uniformly ventilate by only rotating in one direction. Means for Solving the Problems In order to solve the above problems, the grain dryer/storage tank of the present invention has a tank main body formed by a peripheral wall and a bottom wall, and has a large number of ventilation holes. A cylindrical casing in which more than one tube body is arranged upright along the inner surface of the peripheral wall and has a plurality of openings corresponding to the number of tube bodies, and a cylindrical casing that is rotatably located inside the casing and communicates with a high pressure source. A rotary valve device is formed by a cylinder having an air supply port that communicates with a low pressure source and an intake port that communicates with a low pressure source, each of the pipes being individually connected to each of the openings, A rotating device is connected to the cylindrical body so that the air supply port and the intake port communicate with each of the openings individually and periodically. Operation Dry air is sent from a high pressure source, and when the air inlet provided in the cylinder of the rotary valve device and the opening in the casing match, air is blown from one of the pipes provided in the tank body. At this time, the intake port of the cylinder communicates with another opening of the casing and communicates with the low pressure source. Then, the pressure in the other tube connected to this opening becomes low, and the air sent into the tank body is sucked in. Next, when the cylinder is rotated by the rotation device, the opening in the casing that communicates with the air inlet of the cylinder becomes different from the previous opening, and air is blown from other pipes provided with four or more, and Air will be taken in from another pipe body. When the cylinder of the rotary valve device rotates in one direction in this manner, air is sequentially blown from four or more pipes, and air is also sequentially taken in. That is, 1
Blow and intake air is alternately repeated at predetermined intervals from the four tubes, and by combining the blow and intake air from four or more tubes, the air particles in the tank flow in a variety of ways. Embodiments Examples of the present invention will be described with reference to the drawings. As shown in FIG. 1, the tank body 3 is composed of a cylindrical peripheral wall 1, an oblique bottom wall 2, and a truncated conical upper wall 18 having a supply hole 17 in the center.
On the inner surface of the peripheral wall 1, four plates each having a semicircular cross section and having a large number of ventilation holes 4 are attached at equal intervals to form a tube body 5.
a, 5b, 5c, 5d, and these tube bodies 5
a, 5b, 5c, 5d are air supply and intake pipes 101, 10
2, 103, 104 and a rotary valve device having a double cylinder, each of which communicates with a high pressure source having an air supply device (not shown) and a low pressure source having an air intake device (not shown). Although there are four tubes in the drawing, it is of course possible to use a larger number of tubes. The ventilation holes 4 of the pipe bodies 5a, 5b, 5c, and 5d are the fourth
As shown in the figure, it has a diagonally downward guide plate 43 on its upper part, so that grains can be
c, 5d so as not to get inside. The bottom wall 2 of the tank body 3 is provided obliquely with one of the tubes 5c at the upper position, and is made into a double wall with a gap between the upper bottom wall 2a and the lower bottom wall 2b.
A has a large number of air holes 44 opening diagonally downward, and has a switching valve 8 at the lower end of the pipe body 5c in the upper position.By switching this switching valve 8, an air supply/intake pipe extending from a high pressure source and a low pressure source is connected. 103 is communicated with the pipe body 5c or the gap between the upper bottom wall 2a and the lower bottom wall 2b.
19, the switching valve 8 is connected to the upper bottom wall 2a and the lower bottom wall 2b.
A partition plate is used together with the switching valve 8 when closing the gap between the switching valves, 20 is an operating shaft of the switching valve 8, and 21 is a handle. A grain discharge valve 9 is provided at a lower position of the upper bottom wall 2a.
The grain discharge valve 9 is attached to an operating shaft 23 having a handle 22. In this invention, the terms high-pressure source and low-pressure source are used as long as the pressure of one is low relative to the other and air flows from one to the other. For example, a high-pressure source is an air supply fan (not shown), and a low-pressure source is an intake air source. A fan (not shown) is used, or an air supply fan (not shown) is used for the high pressure source and the low pressure source is opened to the atmosphere, or the high pressure source is opened to the atmosphere and an intake fan (not shown) is used for the low pressure source. may also be used. Next, details of the rotary valve device having a double cylinder will be explained in detail with reference to FIGS. 5, 6, and 7.
In these drawings, air supply and intake pipes 101, 102, 103 and 10 are connected to pipe bodies 5a, 5b, 5c and 5d.
A rotary valve device is shown with a double barrel for injecting or inhaling air through 4. A rotary valve device having a double cylinder is rotatably installed on the end face of a double cylinder consisting of an air supply pipe 105 and an intake pipe 106. This rotary valve device consists of a casing 122, a cylinder body consisting of an outer cylinder 118 and an inner cylinder 119, a partition plate 117, and wind shield walls 120, 121. The wind shield wall 121 is provided with ventilation ports 111 and 112, and the outer cylinder 118 is provided with an air supply port 108 and an intake port 10.
9 and 110 are provided, and the inner cylinder 119 is further provided with a vent hole 1.
07 will be provided. The cylindrical body allows the outer circumferential surface of the outer tube 118 and the inner circumferential surface of the casing 122 to slidably fit into contact with each other. The distance between the inner cylinder 119 and the outer cylinder 118 is 8
Openings 113 and 11 are divided into 45-degree sections by two partition plates 117, and are located in four equal parts of the casing 122 that rotatably supports the outer cylinder 118.
Four air supply/intake pipes 101, 102, 103, and 104 are provided on the outer periphery so as to communicate with the air pipes 4, 115, and 116. Of course, the number of air supply and intake pipes can be increased depending on the number of pipe bodies. Furthermore, the rotary valve is 1/
It is configured to be rotated intermittently or continuously by 8 rotations. From the air pipe 105 to the inner cylinder 1
19 and the outer cylinder 118 to pass through the air supply and intake pipe 101,
1 leading to one of 102, 103, 104 sequentially
Two air passages, that is, a vent 107 and an air inlet 108 are provided in the inner cylinder 119 and the outer cylinder 118, and the air intake pipe 106 and the air intake pipes 101, 102, 103,
Two air exhaust passages, ie, intake ports 109 and 110, communicating with the two air cylinders 104 are provided in the outer cylinder 118.
The air supply port 108, the air intake port 109, and the air intake port 110 are spaced apart from each other at angles of 135 degrees, 90 degrees, and 135 degrees. In the figure, the inner cylinder or air pipe 105 is used for air supply, and the outer pipe or intake pipe 106 is used for intake, but it is possible to use the inner cylinder 105 for air intake and the outer pipe 106 for air intake. It is also possible to change the design. Next, an explanation will be given of the operation of supplying or inhaling air to the pipe bodies 5a, 5b, 5c, and 5d by intermittent rotation of the rotary valve device having a double tube at 45-degree increments. First of all, air pipe 105, vent 107, air vent 1
08, While air is being supplied from the air supply and intake pipe 101 and the pipe body 5a, air is taken in through the pipe bodies 5b and 5c and the air supply pipe 1.
02 and 103, intake ports 109 and 110, ventilation port 1
11 and 112, the intake pipe 106, and by turning the rotary valve device 1/8 turn, the air supply remains the same in the pipe body 5a, but the air intake is carried out through the pipe bodies 5c and 5d, the intake pipes 103 and 104, and the intake port. 109 and 110, vents 111 and 112, and intake pipe 106. Further, by rotating the rotary valve device 1/8 turn, the air supply is changed to the tube body 5b, and the air intake is still performed through the tube bodies 5c and 5d. Next, when the rotary valve device is turned 1/8 of a turn, the air supply remains through the tube 5b, but the intake air changes to the tubes 5d and 5a. Furthermore, when the rotary valve device is rotated 1/8 turn, the air supply changes to the tube body 5c, and the intake air changes to the tube body 5c.
d, remains as 5a. Then, when the rotary valve device is rotated 1/8 of a turn, the air supply remains in the tube body 5c, but the intake air changes to the tube bodies 5a and 5b. Next, when the rotary valve device is rotated 1/8 of a turn, air is supplied to the pipe 5d, and air is taken in from the pipes 5a and 5b. Furthermore, when the rotary valve device is rotated 1/8 of a turn, air is still supplied from the tube 5d, but air is taken into the tubes 5b and 5c. Then, when the rotary valve device is rotated 1/8 turn, the air supply changes to the tube body 5a and becomes the initial state. These operations are carried out in a circular manner, and the pipe bodies 5a, 5b,
Air supply or intake is performed at 5c and 5d. The above operating process can be summarized as follows.

[Table] Fig. 8 shows another embodiment of the rotary valve device, in which a high pressure source 206 and a low pressure source 207 are supplied from an air supply fan 225 and an intake fan 226 attached to the shaft of one pulley 224 connected to the motor. The air supply chamber 212 is connected by pipes 227 and 228, respectively.
and communicates with the intake chamber 213. As shown in FIG. 8, the air supply chamber 212 and the intake chamber 213 are formed by dividing an integral casing into left and right sides, and are attached to intermittent rotation devices 229 and 230 and shafts 231 and 232 of the intermittent rotation devices 229 and 230, respectively. It has an air supply rotary valve 210 and an intake rotary valve 211. The air supply rotary valve 210 is rotatably supported by a casing, and has a central hub 233 to which a shaft 231 is attached, as shown in FIG.
It consists of an outer ring 235 which is a cylindrical body, and an arm 241 that connects the central hub 233 and the outer ring 235, and the outer ring 235 has one through hole 237 (corresponding to the air inlet in the first embodiment). There is. Four air holes 239a, 2 are arranged at equal intervals on the cylindrical surface of the casing of the air chamber 212 surrounding the air feeding rotary valve 210.
Openings consisting of 39b (not shown), 239c, and 239d (not shown) are provided, and these air supply holes 23
Air pipes 214a, 214b (not shown), 214 are connected to 9a, 239b, 239c, and 239d, respectively.
c, 214d (not shown). These air pipes 214a, 214b, 214
c, 214d are connected to air supply and intake pipes 216a, 216b (not shown), 216c, 216d (not shown), and the air supply and intake pipes 216a, 216b, 216
c, 216d are tube bodies 5a, 5b, 5c, respectively.
Connects to 5d. The intake rotary valve 211 is rotatably supported by a casing, and as shown in FIG.
and an arm 242 that connects the central hub 234 and the outer ring 236, and the outer ring 236 has two through holes 238 and 238' (corresponding to the air inlet in the first embodiment) spaced apart by 90 degrees. are doing. Four intake holes 240a, 240b are arranged at equal intervals on the cylindrical surface of the intake chamber 213 surrounding the intake rotary valve 211.
(not shown), 240c, 240d (not shown) are provided, and these intake holes 240a, 240b, 24
0c and 240d are the intake pipes 215a and 240d, respectively.
215b, 215c, and 215d. Intermittent rotation devices 229 and 230 operate as follows. That is, the air supply rotary valve 210 having the central hub 233 attached to its shaft 231 is intermittently rotated by the intermittent rotation device 229, and due to the intermittent rotation of the outer ring 235 connected to the central hub 233 via the arm 241, The opening 237 is the air supply hole 2 of the air supply chamber 212.
39a, 239b, 239c, and 239d intermittently, the high pressure source 206 connects to the air supply holes 239a,
Air pipe 2 via 239b, 239c, 239d
14a, 214b, 213c, and 214d intermittently. Similarly, the intermittent rotation device 230 causes the shaft 2
The intake rotary valve 211 to which the central hub 234 is attached to the central hub 234 rotates intermittently, and due to the intermittent rotation of the outer ring 236 connected to the central hub 234 via the arm 242, the through holes 238 and 238' are connected to the intake chamber of the casing. 213 intake holes 240a, 240b, 24
The low pressure source 207 is intermittently connected to the openings 0c and 240d, and the low pressure source 207 is connected to the intake holes 240a, 240b,
Intake pipes 215a, 2 via 240c, 240d
15b, 215c, and 215d intermittently. In this case, when the high pressure source 206 is connected to one air pipe 214a by the intermittent rotation device 229, the low pressure source 207 is connected to the other intake pipes 215b,
215c and 215d, and then the intermittent rotation device 229 operates to connect the high pressure source 206 to the next air supply pipe 214b, and in this state, the intermittent rotation device 230 connects the low pressure source 207 to intake air. Tubes 215c and 215d, 215d and 215a
Intermittent communication is performed in this order, and the same state is repeated in sequence. Therefore, when the high pressure source 206 communicates with the air pipe, the intake pipe that joins the air pipe communicates with the low pressure source 207 through the outer ring 23 of the intake rotary valve 211.
Conversely, if the low pressure source 207 is in communication with the intake pipe, the air supply pipe that merges with the intake pipe is blocked from communicating with the high pressure source 206 by the air supply rotary valve 21.
Since the air is blocked by the outer ring 235 of 0, there is no need to provide a switching valve between the merging air supply pipe and intake pipe. Air pipes 214a, 214b, 21 described above
4c, 214d and intake pipes 215a, 215b,
Air is supplied from 215c and 215d through the intake pipe 21
6a, 216b, 216c, and 216d to pipes 5a, 5b, 5c, and 5d inside the tank body 3, and air is supplied and taken in from each pipe 5a, 5b, 5c, and 5d. That is, while air is being supplied from the tube 5a, air is taken in in the order of tubes 5b and 5c, 5c and 5d, then air is transferred to the tube 5b, and air is taken in from the tube 5a.
Steps c and 5d, and steps 5d and 5a are performed in this order, and the same actions are repeated thereafter. FIG. 11 shows yet another embodiment of the rotary valve device, in which the high pressure source 306 and the low pressure source 307 consist of an air supply fan 325 and an intake fan 326 attached to the shaft of one pulley 324 connected to the motor, It communicates with the air supply chamber 312 and the air intake chamber 313 by pipes 327 and 328, respectively. As shown in FIG. 11, an air supply chamber 312 and an air intake chamber 313 are formed on the left and right sides of an integrated casing,
It has an intermittent rotation device 329 and integrally rotating air supply rotary valve 310 and intake rotary valve 311 attached to shafts 331 and 332 of this intermittent rotation device 329.
The air supply rotary valve 310 is rotatably supported by a casing, and as shown in FIG. 12, includes a central hub 333 to which a shaft 331 is attached, an outer ring 335 of a cylindrical body,
Arm 34 connecting central hub 333 and outer ring 335
1, and has one through hole 337 in the outer ring 335. There are four air holes 339a, 339b (not shown), 33 equally spaced on the cylindrical surface of the air chamber 312 surrounding the air feed rotary valve 310.
9c, 339d (not shown) are provided, and these air supply holes 339a, 339b, 339
Air pipes 314a and 314 are connected to c and 339d, respectively.
b (not shown), 314c, and 314d (not shown). These air pipes 314a, 314b, 314
c, 314d are connected to air supply and intake pipes 316a, 316b (not shown), 316c, 316d (not shown), and the air supply and intake pipes 316a, 316b, 316
c, 316d are tube bodies 5a, 5b, 5c, respectively.
Connects to 5d. The intake rotary valve 311 is rotatably supported by the casing, and as shown in FIG.
The central hub 334 to which the cylindrical body is attached, and the outer ring 336 of the cylindrical body
and an arm 342 communicating between the central hub 334 and the outer ring 336, and the outer ring 336 has two through holes 338, 338' spaced apart by 90 degrees.
There are four intake holes 310a, 340b (not shown), 34 equally spaced on the cylindrical surface of the intake chamber 313 of the casing surrounding the intake rotary valve 311.
0c, 340d (not shown) are provided, and these intake holes 340a, 340b, 340
c and 340d are intake pipes 315a and 315, respectively.
b (not shown), 315c, and 315d (not shown). The angle between the opening 337 provided in the air supply rotary valve 310 (corresponding to the air supply port in the first embodiment) and the openings 338 and 338' provided in the intake rotary valve 311 (corresponding to the intake port in the first embodiment) is 135 degrees. The opening 338 and the opening 338' are formed at an angle of 90 degrees, and the air supply chamber 312 and the intake chamber 3
Air supply holes 339a, 339b, 339 provided in 13
c, 339d and intake holes 340a, 340b, 3
It has a circumferential length of 40c and 340d, that is, a circumferential length that is approximately half the length of approximately 1/4 circumference, that is, approximately 1/8 circumference. Intermittent rotation device 329 operates as follows. That is, by rotating the intermittent rotation device 329 in 1/8 increments, the central hub 3 is attached to its shafts 331 and 332.
Air supply rotary valve 310 with 33 and 334 attached
The intake rotary valve 311 rotates intermittently, and the central hub 3
Due to the intermittent rotation of outer rings 335 and 336 connected to arms 33 and 334 via arms 341 and 342, the opening 337 opens into the air supply hole 33 of the air supply chamber 312.
9a, 339a, 339b, 339b, 339
c, 339c, 339d, 339d intermittently, and the high pressure source 306 connects to the air supply holes 339a, 33
Air supply pipe 314 via 9b, 339c, 339d
a, 314b, 314c, and 314d intermittently. During this time, the intake rotary valve 311 with the central hub 334 attached to the shaft 332 also rotates intermittently, and the central hub 334 rotates intermittently.
Outer ring 3 connected to 34 via arm 342
By intermittent rotation of 36, openings 338 and 338'
are the intake holes 340b and 340c, 3 of the intake chamber 313.
40c and 340d, 340c and 340d, 340
d and 340a, 340d and 340a, 340a and 340b, 340a and 340b, 340b and 34
0c, and the low pressure source 307 connects to the intake pipes 315a, 315b, 315c, 31 through the intake holes 340a, 340b, 340c, 340d.
5d intermittently. In this case, when the high pressure source 306 is communicated with one air pipe 314a by the intermittent rotation device 329, the low pressure source 307 is connected to the other intake pipes 315b and 315c, excluding the intake pipe 315a that merges with this air pipe 314a. , 315c and 315d, and then, by the operation of the intermittent rotation device 329, the high pressure source 306 is connected to the next air supply pipe 314b, and the low pressure source 307 is connected to the intake pipes 315c, 315d, and 315.
d and 315a are intermittently communicated in this order, and the same state is repeated sequentially thereafter. Therefore, when the high pressure source 306 is in communication with the air pipe, the intake pipe that merges with the air pipe is blocked from communicating with the low pressure source 307 by the outer ring 336 of the rotary valve 311, and conversely, the low pressure When the source 307 is in communication with the intake pipe, the air supply pipe that merges with the intake pipe is blocked from communicating with the high pressure source 306 by the outer ring 335 of the rotary valve 310. There is no need to provide a switching valve between the pipes. Air pipes 314a, 314b, 31 described above
4c, 314d and intake pipes 315a, 315b,
Air supply and intake from 315c and 315d is carried out through the air supply and intake pipe 31
6a, 316b, 316c, and 316d to pipes 5a, 5b, 5c, and 5d inside the tank body 3, and air is supplied and taken in from each pipe 5a, 5b, 5c, and 5d. That is, while air is being supplied from the tube 5a, air is taken in in the order of tubes 5b and 5c, 5c and 5d, then air is transferred to the tube 5b, and air is taken in from the tube 5a.
Steps c and 5d and steps 5d and 5a are performed in this order, and the same actions are repeated thereafter. The reason one of the vent pipes stops working when there are four or more vent pipes is that unless a special structure is adopted for the pipe body, the drying force towards the sides of the tank is stronger than the drying force towards the center of the tank (ventilation force). This is because uniform drying will not be achieved because the air flow is large.For example, if there are five ventilation pipes, two of them may be stopped, and as mentioned above, the pipe body itself may not move toward the center of the tank. "Suspension" is not an essential requirement, as there is no need for it to be suspended if it has a special structure that increases the drying power (airflow force). As is clear, the above-mentioned rotary valve achieves air supply and intake to the pipe body by rotational movement in only one direction. Furthermore, by adopting a simple insulation structure in which the outer peripheral wall of the tank is covered with a heat insulating material, there is no risk of condensation forming near the intake pipe body on the inner wall of the tank during the initial stage of operation, even when processing extremely high moisture content of paddy. be able to. Of course, an elevating active block 50 for preventing blow-through is fitted in the upper part of each of the four air supply/intake pipe bodies, and is configured to be able to be raised and lowered according to the amount of paddy stored in the tank. (The elevating mechanism is not shown). This ensures that the air flow due to intake or supply passes through the grain. In the above embodiment, the tank body 3 has a circular cross section, but it may have a rectangular cross section, for example, a square, an octagon, or a rectangular cross section.
It can also be made into 10-sided, 12-sided, etc. Further, the tank bottom wall 2 may be formed horizontally instead of obliquely. Furthermore, it is sufficient that one tube communicates with a high pressure source or a low pressure source, while the other tube communicates with two or more. Effects of the Invention Since the present invention has the above configuration, the rotary valve device can control the air supply and intake to the pipe body by rotating in only one direction, and the control circuit can be extremely easily configured and manufactured at low cost. . In addition, the direction of the airflow flowing inside the tank body is changed sequentially, and the ventilation direction and location are also changed sequentially (rotational alternating ventilation), so that the grains inside the tank body are evenly ventilated and becomes homogeneous moisture. Furthermore, since ventilation is directed from one side wall of the tank to another side wall, sufficient ventilation can be achieved even if the thickness of the top and bottom of the stored grain is increased, and ventilation within the grain is possible even at low pressure. Furthermore, since the part that accommodates the grains is the tank body, it has many advantages, such as not requiring a special reinforcing device for the grain storage part.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of the tank body of the grain dryer/storage tank according to the present invention, and FIG.
3 is a bottom view of FIG. 1 with the lower bottom wall removed, FIG. 4 is a partially enlarged view of FIG. 1, and FIG. 5 is a grain according to the present invention. A sectional view taken along the line C-C in Fig. 6 of the rotary valve device in the grain dryer/storage tank, Fig. 6 is a sectional view taken along the line B-B in Fig. 5, and Fig. 7 shows the rotating valve device. FIG. 8 is a sectional view of another embodiment of the rotary valve device, FIG. 9 is a longitudinal sectional view of the rotary valve in the rotary valve device of FIG. 8, and FIG. 10 is a cross-sectional view of another embodiment of the rotary valve device. FIG. 11 is a cross-sectional view of yet another embodiment of the rotary valve device, FIG. 12 is a vertical cross-sectional view of the rotary valve in the rotary valve device of FIG. 11, and FIG. FIG. 3 is a longitudinal cross-sectional view of another rotary valve shown in the figure. 1... Peripheral wall, 2... Bottom wall, 3... Tank body,
4...Vent hole, 5a, 5b, 5c, 5d...Pipe body, 2a, 2b,...Double wall, 8...Switching valve,
9... Discharge valve, 43... Guide plate, 44... Stomata,
101, 102, 103, 104... air intake pipe,
105...Air supply pipe, 106...Intake pipe, 117...
...Partition plate, 118... Outer cylinder, 119... Inner cylinder.

Claims (1)

[Claims] 1 A tank body is formed by a peripheral wall and a bottom wall,
Four or more tubes having a large number of ventilation holes are arranged upright along the inner surface of the peripheral wall, and a cylindrical casing with a plurality of openings corresponding to the number of the tubes, and a rotatable tube inside the cylindrical casing. a cylinder having an air inlet communicating with a high pressure source and an inlet communicating with a low pressure source forming a rotary valve arrangement, each of said tubes being individually connected to each of said openings; A rotating device is connected to the cylindrical body so that the air supply port and the suction port of the cylindrical body are individually and periodically communicated with each of the openings. tank.