JPH0545055A - Continuous type multistage dryer - Google Patents

Abstract

PURPOSE:To obtain a continuous type multistage dryer in which cleaning of a porous plate, maintenance of a rotary scraper can be facilitated in a simple structure. CONSTITUTION:A continuous type multistage dryer comprises porous plates 4 disposed at many upper and lower stages with hot air passing from below to upward, rotary scrapers 18 disposed on the plates 4, and particle dropping ports formed at predetermined positions of the plates 4. Each scraper 18 is formed of a boss 20, and scraper blades 48 extended radially outward from the boss 20, and each plate 4 has an opening 16 for vertically separably engaging the bosses of the scrapers by engaging holes 26 and engaging pins 28. Thus, the boss 20 engaged with the scrapers is composed as one driving shaft to be coupled to a drive source.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous multistage dryer for continuously drying a large number of granules.

[0002]

2. Description of the Related Art A continuous multi-stage dryer of this type is for continuously and efficiently drying granules obtained by curing droplets by a chemical reaction, and these dryers are, for example,
JP-A-1-174883 and JP-A-1-17448
It is known from Japanese Patent Publication No. 84. These known multi-stage dryers, perforated plates arranged at intervals in the vertical direction,
A drive shaft that rotatably penetrates through these perforated plates, a rotary scraper that is attached to this perforated plate and that is rotatable on each perforated plate, a drop port for granules provided on each perforated plate, and a perforated plate. And hot air generating means for generating hot air flowing through the plate.

According to such a multi-stage dryer, when the granules before drying are dropped on the uppermost porous plate, the granules are
With the rotation of the rotary scraper, the rotary scraper is moved toward the drop port of the perforated plate, and is dropped from the drop port onto the next lower perforated plate. Then, similarly, the particles on the next lower porous plate are also sequentially dropped on the lower porous plate by utilizing the rotation and the dropping port of the rotary scraper, and finally the lowermost porous plate. It will be discharged from the drop port of the board.

On the other hand, since the granules on each porous plate are exposed to the hot air flowing through the perforated plate, the granules are discharged from the drop opening of the porous plate in the lower stage again. , The granules will be dried.

[0005]

By the way, the granules in the drying process and the drying process, which are subjected to the drying treatment by the multi-stage dryer of this kind, are generally weak, and therefore, the granules are rotated on each porous plate. When it is moved by being pushed out by a dynamic scraper, some of the particles are broken or damaged.

[0006] The destruction or damage of the granules results in fine particles that remain on the perforated plate, and such debris is generated by the multi-stage dryer for a long period of time. The small holes, that is, the small holes through which the hot air passes will be clogged. Here, in this type of multi-stage dryer, even if one porous plate is clogged, the amount of hot air flowing through each porous plate is greatly reduced. Will decrease the drying efficiency.

Therefore, when one of the perforated plates becomes clogged, the perforated plate must be taken out and cleaned. However, in the above-mentioned known multi-stage dryer, the drive shaft extends through each perforated plate, and a rotary scraper that cooperates with each perforated plate is attached to this drive shaft. Therefore, in order to take out the perforated plate to be cleaned, it is necessary to pull out the drive shaft from the perforated plate, and in order to pull out this drive shaft, it is necessary to remove each rotary scraper from the drive shaft in advance.

Therefore, in the case of the known multi-stage dryer, it takes a lot of time and labor to clean the perforated plate and maintain the rotating scraper and the like. The present invention has been made based on the above-mentioned circumstances, and an object of the present invention is to provide a continuous multi-stage dryer capable of easily performing cleaning of a perforated plate, maintenance of a rotary scraper, and the like. is there.

[0009]

SUMMARY OF THE INVENTION The continuous multi-stage dryer of the present invention is basically arranged vertically with a predetermined interval and detachably connected to each other, and has a large number of small holes penetrating therethrough. Formed perforated plate, a rotating scraper rotatably arranged on each perforated plate coaxially with each other, provided on each perforated plate, when the granules are dropped on the uppermost perforated plate,
Using the rotation of the rotary scraper, the particles on each perforated plate are sequentially dropped onto the next lower perforated plate and passed through the drop ports that can be discharged from the lowermost perforated plate and the small holes of each perforated plate. And a hot air supply means for generating a flow of hot air flowing therethrough. And in the multi-stage dryer of the present invention,
Each of the rotating scrapers comprises a central shaft portion and scraper blades extending radially outward from the shaft portion, while each porous plate has boss portions of the rotating scraper that can be vertically separated from each other. There is an opening for engagement, whereby the mutually engaged shaft portions of each rotary scraper are configured as one drive shaft connected to the drive source.

[0010]

According to the above-mentioned continuous multi-stage dryer, when the granules to be dried are dropped on the uppermost perforated plate, the granules move on the perforated plate by the rotation of the rotary scraper. Then, it is dropped from the drop hole onto the next lower perforated plate, and thereafter, in the same manner, from the perforated plate to the next lower perforated plate in sequence, the drop hole from the lowermost perforated plate is dropped. Exhausted through. In this way, in the process of the granules successively descending each porous plate, the granules are heated by the hot air supplied from the hot air generating means through each porous plate, To be dried.

In the case of the multi-stage dryer of the present invention, when cleaning of a specific perforated plate or maintenance of a specific rotary scraper becomes necessary, the mutual connection between the perforated plates is removed from a predetermined position, and the connection is removed. The perforated plate and the rotary scraper in the upper stage are lifted up from the release position, and in this state, the desired perforated plate and the rotary scraper are removed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, one embodiment of a continuous multi-stage dryer is shown. This multi-stage dryer is provided with an upright box-shaped frame 2, and a large number of perforated plates 4 arranged at predetermined intervals in the vertical direction are arranged in an upper portion of the frame 2. Each perforated plate 4 has a circular shape,
As is clear from FIG. 2, the outermost peripheral plate 4 of the lowermost stage is detachably fixed to the frame 2 at four points by a connecting piece 6 and a pair of bolts and nuts 8.

The perforated plate 4 located above the lowermost perforated plate 4 has a spacer 10 interposed between the perforated plate 4 and the lower perforated plate 4, so that they are mutually spaced at equal intervals in the vertical direction. It is detachably connected. More specifically, the perforated plates 4 other than the lowermost perforated plate 4 also have the outer peripheral edge 4
The connecting piece 6 is attached to the location through a pair of bolts and nuts 8. The connecting piece 6 of each perforated plate 4 is projected from the outer peripheral edge of the perforated plate 4, as is apparent from FIG. It has become a thing. Further, in the case of this embodiment, the spacers 10 made of a pipe material are arranged between the connecting pieces 6 and outside the perforated plate 4, and the connecting pieces 6 vertically adjacent to each other are provided with the spacers 10. They are connected to each other by connecting bolts and nuts 12 extending through the inside. In addition,
The upper and lower connecting bolts and nuts 12 are alternately arranged in the circumferential direction of the perforated plate 4, as shown in FIG. 3, in order to avoid interference in fastening and unfastening them.

Each of the perforated plates 4 is a so-called punching plate. Therefore, a large number of small holes 14 are formed through the entire surface thereof, as shown in a part of FIG.
Further, a circular opening 16 is formed in the center of each porous plate 4. The openings 16 have the same inner diameter dimension and are located on the same axis. Therefore, when the multi-stage perforated plate 4 is viewed as a whole, a circular through hole is formed in the central portion so as to penetrate in the vertical direction.

A rotating scraper 18 having a diameter smaller than that of the perforated plate 4 is disposed on each perforated plate 4. These rotary scrapers 18 are, as shown in FIG.
The boss portion 20 is provided at the center of the boss portion 20.
Has a thickness slightly larger than the length defined by the spacer 10 described above. As shown in an enlarged view in FIG. 5, the boss portion 20 has a ring-shaped protrusion 22 on the upper surface, and the protrusion 22 has a diameter larger than the inner diameter of the boss 22 and a perforated plate. 4 has an outer diameter dimension that can be fitted in the four openings 16. On the other hand, a recess 24 that is slightly larger than the protrusion 22 is formed on the lower surface of the boss 20.

Further, the projection 22 is formed with four engagement holes 26 on the same circumference at equal intervals in the circumferential direction, while the recess 24 extends from the engagement hole 26. The engaging pin 26 corresponding to is provided so as to project downward from the lower surface of the boss portion 20. That is, the corresponding engagement hole 26 and engagement pin 28
And are located on the same axis. Therefore, if the boss portion 20 of each rotary scraper 18 has the above-described configuration, as shown in FIG. 2, the boss portion 20 of the rotary scraper 18 located on the lower side, that is, the protrusion 22 thereof is moved upward. It can be inserted into the opening 16 of the adjacent perforated plate 4 so as to project from this perforated plate 4, and further, the protrusion 2
2, the boss portion 20 of the rotary scraper 18 located on the upper side,
That is, it can be fitted into the recess 24. At this time, the engaging pin 28 of the upper boss portion 20 is inserted into the corresponding engaging hole 26 of the boss portion 20 adjacent to the lower side,
As a result, the vertically adjacent bosses 20, that is, the bosses 20 of each rotary scraper 18 function as one drive shaft.

The drive shaft of each rotary scraper 18 constructed as described above is connected to the power transmission shaft 30. Specifically, below the lowermost perforated plate 4, a sleeve 32 having the same diameter as the boss 20 is arranged coaxially with the rotary scraper 18, and this sleeve 32 is not shown. However, it is supported on the frame 2 side.

The power transmission shaft 30 extends vertically in the sleeve 32, and is rotatably supported by the sleeve 32 via a pair of bearings 34 and 36. The upper end of the power transmission shaft 30 is formed as a flange end 38, and the flange end 38 passes through the opening 16 of the perforated plate 4 located at the lowermost stage, and the rotary scraper 18 adjacent to the upper side, that is, the boss portion thereof. It is fitted in the recess 24 of 20. At this time, the flange end 38 is formed with an engagement hole 40 into which the engagement pin 28 of the boss portion 20 can be inserted. Therefore, since the rotary scraper 18 at the lowermost stage and the power transmission shaft 30 are connected in this manner, each rotary scraper 18 is connected to the power transmission shaft 3
It can rotate with 2.

The rotary scraper 1 located at the uppermost stage
8, a lid 42 is arranged on the protrusion 22 of the boss portion 20 as needed, and the lid 42 projects from the lower surface of the lid 42 and is inserted into the engagement hole 26 of the boss portion 20. The engagement pin 28 can be fixed to the boss portion 20. On the other hand, the lower end of the power transmission shaft 30 is connected to an electric motor 46 via a speed reducer 44, as shown in FIG.

As shown in FIG. 4, each rotating scraper 18 is provided with a plurality of scraper blades 48 extending radially from the boss portion 20 at equal intervals in the circumferential direction of the boss portion 20. .. These scraper blades 48 are configured by bonding a Teflon plate 52 to a metal plate 50, and the Teflon plate 52 is positioned on the front side of the metal plate 50 when viewed in the rotation direction of the rotary scraper 18 shown by the arrow in FIG. Has been. Further, although not shown in FIG. 4, the outer surface of the Teflon plate 52 is actually corrugated as shown in FIG.

In each rotating scraper 18, a portion of each scraper blade 48 on the outer end side is bent forward in the rotation direction, and an adjacent outer end of the scraper blade 48 has an acrylic cover plate 54. Are interconnected by. Needless to say, the lower edge of the cover plate 54 also moves so as to make sliding contact with the corresponding perforated plate 4 similarly to the scraper blade 48.

Referring again to FIG. 1, as is clear,
Immediately above the rotary scraper 18 located at the uppermost stage, a granule charging guide tube 56 is arranged. The lower end of the charging guide pipe 56 opens toward the rotary scraper 18, and the rotary valve 58 is attached to the upper end thereof. Although not shown, the rotary valve 58 is connected to a grain conveyer via a hopper. Therefore, the grain conveyed on the conveyer conveys the hopper, the rotary valve 58 and the charging guide pipe 56. It is dropped onto the uppermost perforated plate 4 via the via. Here, the rotary valve 58 is a valve for smoothly guiding the particles regardless of the pressure difference between the inside of the dryer and the outside air. Since the rotary valve 58 is already known, its description will be omitted. Omit it. In FIG. 1, reference numeral 60 indicates a motor that drives the rotary valve 58.

Each of the porous plates 4 described above has a drop port 62 formed at a predetermined position as viewed in the circumferential direction. The drop opening 62 has a rectangular shape that extends radially outward from the boss portion 20 of the rotary scraper 18 to the cover plate 54. Here, the drop openings 62 of the vertically adjacent porous plates 4 are located immediately before the drop openings 62 of the upper porous plate 4 as viewed in the rotation direction of the rotary scraper 18. They are arranged so that they are located at.
It is needless to say that the lower end opening of the charging guide tube 58 described above is also positioned immediately in front of the drop opening 62 of the perforated plate 4 at the uppermost stage in the rotation direction of the rotary scraper 18.

A discharge guide pipe 64 is arranged at the drop port 62 of the lowermost porous plate 4, and a rotary valve 66 similar to the rotary bubble 58 described above is connected to the lower end of the discharge guide pipe 64. Has been done. Although not shown, a transfer conveyor extends from below the outlet of the rotary valve 66. On the other hand, the hot air is supplied from the lower side to the perforated plates 4 arranged in multiple stages, and this hot air supply means, first, as shown by the chain double-dashed line in FIG. A cover case 68 that covers the periphery of the multi-stage perforated plate 4 in an airtight manner is provided, and the supply port of the rotary valve 58 and the discharge port of the rotary valve 66 described above are opened outside the cover case 68, respectively. ..

Then, inside the cover case 68, the hot air blown out toward the perforated plate 4 is located below the perforated plate 4 at the lowermost stage, avoiding the discharge guide tube 64 and the sleeve 32 described above. A mouth portion 70 is arranged, and one end of a blower duct 72 is connected to the air outlet portion 70. The other end side of the blower duct 72 penetrates the cover case 68 in an airtight manner to extend to the outside, and the other end is connected to a cylindrical air suction port 74. A heater 76 is housed in the suction port 74, and a pre-filter 78 is arranged at the open end of the suction port 74.

On the other hand, inside the cover case 68, there is provided an exhaust port 80 which is located above the uppermost porous plate 4 and is open. The exhaust port 80 is connected to an exhaust duct 82. The exhaust duct 82 also penetrates the cover case 68 in an airtight manner, extends outward, and is connected to an exhaust fan 84 that can be driven by an electric motor.
A cylindrical exhaust port 88 is connected to the exhaust port of the exhaust fan 84 via a connecting pipe 86, and activated carbon 90 is housed in the exhaust port 88.

Therefore, when the exhaust fan 84 is driven,
The air in the cover case 68 is exhausted from the exhaust port 80 through the exhaust duct 82 and the exhaust port portion 88, whereby
The pressure inside the cover case 68 becomes a negative pressure. When the pressure inside the cover case 68 becomes negative, air is introduced from the open end of the suction port 74, and this air is heated by the heater 76 to become hot air, and this hot air is blown out through the blower duct 72. Is blown toward the perforated plate 4. The hot air blown out in this way is applied to each porous plate 4
After passing through the small hole 14 of FIG. The exhaust fan 84, the suction port portion 74, and the exhaust port portion 88 described above are supported by a frame arranged near the frame 2.

Next, the operation of the above-described multi-stage dryer will be described. When hot air is introduced into the cover case 68, each rotating scraper 18 is driven by the electric motor 46 at this time. It receives power from the power transmission shaft 30 and rotates in synchronization. That is, in each rotary scraper 18, vertically adjacent boss portions 20 are engaged with each other to form one drive shaft, so that the drive shaft and the power transmission shaft 30 rotate integrally. By doing so, each rotating scraper 18 also rotates in synchronization with the corresponding perforated plate 4.

In this state, when the granules to be dried are continuously dropped onto the uppermost perforated plate 4 from the throwing guide tube 56 through the rotary valve 58, the dropped granules. Is the rotation of the rotary scraper 18, that is,
As it is extruded by the scraper blades 48, it is moved on the perforated plate 4 and, when the particles reach the drop port 62 of the perforated plate 4, through the drop port 62, the next lower porous plate 4 Dropped on. Further, the granules supplied onto the next lower perforated plate 4 are also dropped by the rotary scraper 18 cooperating with the perforated plate 4.
It is moved up to and is dropped on the porous plate 4 below it.

As described above, when the granules successively descend on the perforated plates 4 and the granules are dropped from the drop opening 62 of the lowermost perforated plate 4, the granules are dropped. Is
It is discharged from the cover case 68, that is, the multi-stage dryer via the discharge guide tube 64 and the rotary valve 66. In the process in which the granules are transferred while descending sequentially from the uppermost perforated plate 4 to the lowermost perforated plate 4,
Since the granules are exposed to the hot air flow described above,
The granules are dried by the hot air and then discharged from the dryer.

When the above-mentioned multi-stage dryer is used for a long period of time, when fine particles of fine particles are generated on the perforated plate 4 due to breakage or damage of the fine particles, the fine particles are small holes in the perforated plate 4. It will also clog 14 and block these small holes.
The clogging of the perforated plate 4 reduces the flow rate of the hot air, which greatly reduces the drying efficiency of the granules.

In such a situation, it is necessary to clean the clogged perforated plate 4. In this case, in the multi-stage dryer of this embodiment, the cleaning is carried out as follows. can do. First, the cover case 68 is removed, and the connection between the perforated plate 4 to be cleaned and the vertically adjacent perforated plates 4 is connected to the connecting bolts and nuts 12.
Remove by removing each.

Thereafter, by using an unillustrated hoist or the like, the upper portion from the adjacent porous plate 4 above is collectively lifted with respect to the porous plate 4 to be cleaned, and the upper portion is It is easily separated from the side of the perforated plate 4 to be cleaned. That is, as described above, in each rotating scraper 18, the vertically adjacent boss portions 20 are only engaged with each other through the engaging pins 28, so that the upper portion is simply lifted. The drive shaft of each rotary scraper 18 is separated from a predetermined level position.

Therefore, if the upper part is lifted by the height required to pull out the set of rotary scrapers 18 and the perforated plate 4 to the side, the perforated plate 4 to be cleaned and its rotary scraper 18 are temporarily raised. If you pull it to the side after floating
The perforated plate 4 and the rotary scraper 18 can be easily removed, whereby the perforated plate 4 and the rotary scraper 18 can be easily maintained.

After the cleaning of the perforated plate 4 is completed, the above-mentioned procedure for removing the perforated plate 4 is carried out in reverse to remove the cleaned perforated plate 4 from the rotary scraper 18.
At the same time, it can be easily installed in the original position. The present invention is not limited to the above-described embodiment. For example, the number and shape of the scraper blades 48 in the rotary scraper 18 and the drive shaft including each boss portion 20 of the rotary scraper 18 are not limited to the above. The mechanism for transmitting power can be changed and implemented in various ways.

[0036]

As described above, according to the continuous multi-stage dryer of the present invention, the vertically adjacent shafts of the rotary scrapers arranged on the perforated plates are engaged with each other so that they can be separated from each other. As a result, since it is configured as one drive shaft, in order to rotate each rotary scraper, it is only necessary to transmit power to the drive shaft, and the drive mechanism does not become complicated. When a specific perforated plate needs to be cleaned, the connection between the perforated plate to be cleaned and the vertically adjacent perforated plates is released, and the part above the perforated plate to be cleaned is removed. The perforated plate together with the rotary scraper can be easily removed to the side simply by lifting, and cleaning and maintenance of these can be easily performed, and the drying efficiency of the dryer itself can be maintained. ..

[Brief description of drawings]

FIG. 1 is a schematic view showing an entire continuous multi-stage dryer according to an embodiment.

FIG. 2 is an enlarged cross-sectional view showing a part of a perforated plate and a rotary scraper arranged in a stack.

FIG. 3 is a side view showing a part of perforated plates arranged in a stack.

FIG. 4 is a plan view showing a rotating scraper.

FIG. 5 is an enlarged cross-sectional view showing a boss portion of the rotating scraper.

FIG. 6 is a cross-sectional view showing a part of scraper blades in a rotating scraper.

[Explanation of symbols]

 4 Perforated Plate 16 Opening 18 Rotating Scraper 20 Boss (Shaft) 26 Engagement Hole 28 Engaging Pin 30 Power Transmission Shaft 48 Scraper Blade 62 Drop Port 68 Cover Case 70 Blowout Portion 72 Air Duct 76 Heater 80 Exhaust Port 82 Exhaust duct 84 Exhaust fan

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kimio Masuko 4-13-20 Sake, Odawara-shi, Kanagawa Japan Tobacco Inc. Seawater Research Institute (72) Inventor Narimichi Takei 5-Chiyoda, Sakado, Saitama Prefecture 1-23 Freund Industrial Co., Ltd. Technology Development Laboratory (72) Inventor Kaoru Kurita 5-1-23 Chiyoda, Sakado City, Saitama Pref.

Claims (1)

[Claims] 1. A perforated plate having a predetermined space in the vertical direction and detachably connected to each other and formed by penetrating a large number of small holes; Movable rotating scraper and each porous plate, when the particles are dropped on the uppermost porous plate, the rotation of the rotary scraper is used to move the particles on each porous plate to the next position. It is equipped with a drop port that is sequentially dropped on the lower perforated plate so that it can be discharged from the lowermost perforated plate, and a hot air supply means that generates a flow of hot air flowing through the small holes of each perforated plate. The rotating scrapers include a central shaft portion and scraper blades extending radially outward from the shaft portion, and the shaft portions of the rotating scraper are vertically separated from each other in each porous plate. Has an opening for enabling and engaging. , The shaft portion engaged with each other in each rotational scraper, a continuous multistage drier, characterized in that it is configured as a single drive shaft connected with the driving source.