JP2000199684A - Indirect heating stirrer/dryer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an indirect stirrer/dryer having self cleaning function in which adhesion of adhesive powder to a disc is reduced and drying efficiency is enhanced by constructing the disc of first and second transfer discs above the substantially first half section of a hollow shaft in the axial direction and first and second stirring discs above the substantially second half section thereof. SOLUTION: Hollow shafts 5, 6 rotating at a substantially same speed in the opposite directions are arranged horizontally in parallel in a easing. Hollow sectral first transfer discs 7 are arranged above the substantially first half section of the hollow shaft 6 in the axial direction and second hollow sectral transfer discs 8 are arranged at a constant interval in the hollow shaft 5. First stirring discs 15 having front end face inclining at a specified angle in the carrying direction of material with respect to the axis of the hollow shaft 5, 6 and rear end face arranged with stirring blades, and second stirring discs 18 having front end face in the rotational direction inclining at a specified angle oppositely to the carrying direction of material with respect to the axis of the hollow shaft 5, 6 and rear end face arranged with stirring blades are fixed, at a specified interval, perpendicularly to the axis above the substantially second half section of the hollow shaft 5, 6 in the axial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an indirect heating type agitating / drying machine which has a self-cleaning property while agitating and drying an adhesive powder, particularly a high moisture material or a highly sticky material by conduction heating.

[0002]

2. Description of the Related Art Conventionally, various indirect heating-type stirring / stirring dryers for stirring and drying a material containing moisture (water-containing powdery particles) by conduction heating have been proposed. Tube type, screw type, member type and the like are well known as this type of dryer. Among them, as a member shape, for example, an indirect heating type stirring / stirring dryer proposed by the present applicant can be mentioned (JP-A-63-279086). In this device, a pair of hollow shafts rotating at the same speed in opposite directions to each other are horizontally arranged in parallel inside a casing, and a hollow fan-shaped stirring disk is provided on both hollow shafts in a direction orthogonal to the axis of the hollow shaft. An indirectly heated stirring and drying machine, which is arranged at a constant angle in a rotational direction and communicates with the hollow interior of the hollow shaft at a regular interval, wherein the stirring disk is different from a first stirring disk having a different shape. A second stirring disk, wherein the front end surface in the rotation direction of the first stirring disk is agitated to a feed cut surface inclined at a predetermined angle to a feed direction side of the adhesive powder with respect to the axis of each hollow shaft and to a rear end surface. Blades are formed, and the front end face in the rotation direction of the second stirring disk is formed on the return cut face inclined at a predetermined angle to the opposite side to the feed direction of the adhesive powder with respect to the axis of each hollow shaft, and on the rear end face. The stirring blade is shaped In addition, the first stirring disk and the second stirring disk are alternately arranged in the axial direction of each hollow shaft, are arranged symmetrically with respect to the axis in the orthogonal direction, and are disposed between the two hollow shafts. In the axial direction, the second stirring disk or the first stirring disk on the other hollow shaft is arranged to face each other between the first stirring disk or the second stirring disk on one hollow shaft. (See FIGS. 8 and 9 described in the embodiment of the present invention). This agitating dryer eliminates non-uniform drying of the adhesive powder that stays in the dead space and the adhesive powder that is transported without staying in the dead space, and prevents the deterioration of product quality. It was made for the purpose.

[0003]

However, in the indirect heating type agitating / drying machine having the above-described structure, a stirring blade having a width larger than the thickness of each hollow fan-shaped agitating disk is provided at the rear end face thereof. Because it is provided,
The gap between the opposing side surfaces of the disk becomes large, and in the case of processing of the adhesive powder such as high moisture, there is a problem that the adhesive powder attached to the side surface of the disk cannot be sufficiently scraped. there were.

Accordingly, the present invention improves the above-mentioned conventional problems, minimizes the adhesion of adherent powder such as high moisture to a disc or the like, and has a self-cleaning property.
It is another object of the present invention to provide an indirectly heated agitating dryer capable of increasing the drying efficiency.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an indirect heating type agitator / dryer of the present invention comprises a supply port for adhering powder at one upper end and a dried powder supply port at the lower end. A pair of hollow shafts, which rotate at the same speed in opposite directions to each other, are horizontally arranged inside a casing having a discharge port, and a hollow fan-shaped disk is provided on one hollow shaft and the other hollow shaft 5 is provided thereon.
An indirect heating type stirring and drying system in which a number of hollow fan-shaped stirring disks are arranged at regular intervals in the direction of rotation in the direction perpendicular to the axis of the hollow shaft and communicate with the hollow interior of the hollow shaft. The first transfer disk 7 and the second transfer disk 8 on the substantially front half of the hollow shafts 5 and 6 in the axial direction, and the first stirring disk 1 on the substantially rear half thereof.
5, a second stirring disk 18;
The transfer disks 7, 8 have outer peripheral surfaces formed substantially parallel to the inner surface of the casing 1 and front end surfaces in the rotation direction formed on feed cut surfaces 9, 11, which are inclined with respect to the feed direction. The second transfer disks 7 and 8 are arranged such that the second transfer disk 8 on the other hollow shaft 5 is located between the first transfer disk 7 on one hollow shaft 6 and the other in the axial direction of the hollow shafts 5 and 6. The first transfer disk 7 on one hollow shaft 6 is located between the second transfer disks 8 on the hollow shaft 5 and the first transfer disk 7
Small gaps δ1 and δ2 are formed between the opposing side surfaces of the first and second transfer disks 8 and between the outer peripheral surfaces of the first and second transfer disks 7 and 8 and the surfaces of the hollow shafts 5 and 6, respectively. The second transfer disks 7 and 8 have a small gap δ3 between the outer peripheral surface thereof and the inner surface of the casing below the axis of the hollow shafts 5 and 6, and the front end surface of the first stirring disk 15 in the rotation direction is formed. The agitating blades 14 are formed on the feed cut surface 13 inclined at a predetermined angle in the feed direction of the adhesive powder with respect to the axial direction of the hollow shafts 5 and 6, and the stirring blades 14 are formed on the end surfaces. The front end face in the direction is opposite to the feeding direction of the adhesive powder with respect to the axial direction of the hollow shafts 5 and 6, the return cut face 16 inclined by a predetermined angle, and the stirring blade 1 on the rear end face.
7 are formed, and the first stirring disk 15 and the second stirring disk 18 are alternately arranged in the axial direction of the hollow shafts 5 and 6, respectively, and are symmetrical with respect to the axial direction in the orthogonal direction. The first stirring disk 15 on the other hollow shaft 5 is disposed between the first stirring disk 15 or the second stirring disk 18 on one hollow shaft 6 in the axial direction between the hollow shafts 5 and 6. Or the second stirring disk 18
Is disposed so as to face the second stirring disk 18 or the first stirring disk 15 on one of the hollow shafts 6.

Further, the casing is inclined downward by several degrees or less from the supply port side to the discharge port side.

[0007]

Embodiments of the present invention will be described with reference to the drawings. 1 to 6, reference numeral 1 denotes a double U-shaped casing, on which a jacket 2 is attached to an outer surface,
A lid 4 is attached to the opening 3 of the casing 1. Inside the casing 1, hollow shafts 5, 6 which rotate at the same speed in opposite directions as indicated by arrows are arranged horizontally in parallel. A hollow fan-shaped first transfer disk 7 is provided on a substantially front half of the hollow shaft 6 in the axial direction, and a similar hollow fan-shaped second transfer disk 8 is provided on the hollow shaft 5. A plurality of them are arranged at equal intervals in a direction perpendicular to the heart. That is, the first transfer disk 7 and the second transfer disk 8 do not overlap each other in the circumferential direction on the hollow shafts 5 and 6 adjacent to each other in the axial direction, and every other one has a fixed angle in the rotational direction. The front end face of the first transfer disk 7 in the rotation direction is shifted to the cut surface 9 inclined with respect to the feeding direction of the adhesive powder, and the rear end face is parallel to the feeding (axial) direction of the adhesive powder. A cut surface 11 formed on the cut surface 10 and having a front end surface in the rotation direction of the second transfer disk 8 inclined with respect to the feed (axial) direction of the adhesive powder,
The rear end surface is formed on a cut surface 12 parallel to the direction of feeding (axial center) of the adhesive powder.

The relationship between the mounting arrangement of the first and second transfer disks 7 and 8 will be further described with reference to FIGS. The first and second transfer disks 7 and 8 have a thickness T in the axial direction, a sector angle α in a plane perpendicular to the axis, an angle γ of the cut surfaces 9 and 11, an outer diameter D, and an equal interval P. Has become.
δ ₁ is the first and second transfer disks 7,
8 is a small gap between the opposing side surfaces, and has a relationship of P = T + δ ₁ . β ′ is an angle on the outer peripheral development of the first and second transfer disks 7, 8 calculated from the angle γ of the cut surfaces 9, 11 of the disks, and sin β ′ = T · tanγ / 1/2 · D (1) And β has a relationship of sinβ = P · tanγ / 1/2 · D (2).

In FIG. 7, which shows a developed view of the outer periphery of the first and second transfer disks 7, 8, the first transfer disk 7 on the hollow shaft 6 is located at the first pitch position (right 1).
Is 0 ° as a reference point, the first transfer disks 7 (right 3...) At odd pitch positions are shifted by an angle (β + θ),
The first transfer disk 7 (right 2) at the position of the second pitch is 18
With the 0 ° + θ as the reference point, the first transfer disks 7 (right 4...) At even-pitch positions are shifted by an angle (β + θ). Similarly, in the hollow shaft 5, the second transfer disk 8 (left 1) at the first pitch position has a reference point of 180 ° and the second transfer disk 8 (left 3 ...) at the odd pitch position has an angle (β +
θ), the second transfer disk 8 (left 2) at the second pitch position has the angle θ as a reference point, and the second transfer disk 8 (left 4...) at the even pitch position has the angle (β + θ). )
Are off by one. When the hollow shafts 5, 6 provided with the first and second transfer disks 7, 8 are rotated at a constant speed in the direction indicated by the arrow in FIG. 7 so that β = θ, the points D, E and D 'are obtained. The point and the E 'point overlap each other. That is, the second transfer disk 8
Side of the first transfer disk 7 which faces at slight clearance [delta] ₁ with the side D-D'represented by E-E'(left 2) (Right 1) is mutually once scraping each other in one rotation (Self cleaning). The condition of self-cleaning as described above is that θ is equal to β or β ′. However, since the cut surfaces 9 and 11 of the first and second transfer disks 7 and 8 are planes formed by the angle γ, It is also necessary to consider self-cleaning at the root of the disk (a part near the surface of the hollow shaft). For this purpose, by selecting an appropriate shift angle θ for β determined by γ, D, and P,
It is possible to scrape almost the entire surface.

Now, the sector angle α of the first and second transfer disks 7, 8 is 140 °, the shift angle θ is 20 °, and the angle γ is 4
5 ° is selected, and the engagement locus of the opposing side surfaces of the first transfer disk 7 (right 1) and the second transfer disk 8 (left 2) shown in FIG. 7 is graphically represented by a computer (not shown). It was found that almost the entire two opposing surfaces were scraped together. Usually, the first and second transfer disks 7,
8 is 120 to 150 °, the angle γ of the cut surfaces 9 and 11 is 5 to 45 °, the small interval δ1 between the first transfer disk 7 and the second transfer disk 8 is 3 to 5 mm, and the first
Tip of transfer disk 7 and second transfer disk 8 (outer peripheral surface)
The small gap δ2 between the outer peripheral surfaces of the hollow shafts 5 and 6 is 2.5
(3) It is preferable to set the small gap δ3 between 5 mm and the tip (outer peripheral surface) of the first and second transfer disks 7 and 8 and the inner wall of the casing 1 to 3 to 5 mm.

Thus, the first and second transfer disks 7, 8
Are opposed once per rotation with a small gap δ1, so that the effect of scraping (dropping) the powder adhering to the disk side surface is increased, and stirring is performed between the small gaps δ1. Therefore, the heat transfer coefficient from the disk side surface to the powder becomes extremely large. Furthermore, the outer peripheral surfaces of the first transfer disk 7 and the second transfer disk 8 allow the inner wall surface of the casing 1 (heat transfer surface) and the outer surfaces of the hollow shafts 5 and 6 (heat transfer surface).
The adhesive powder adhered to the surface can be scraped off, the contact between the heat transfer surface and the adhesive powder is constantly updated, and the heat transfer efficiency is significantly increased.

As shown in FIGS. 8 and 9, the front end face of the hollow shafts 5 and 6 is disposed with respect to the shaft centers of the hollow shafts 5 and 6 so that the adhesive powder as a raw material is formed. A first stirring disk 15 formed on a cut surface 13 inclined at a predetermined angle in the feed direction and having a stirring blade 14 on a rear end surface, and a front end surface in the rotation direction having an adhesive property with respect to the axis of the hollow shafts 5 and 6. A second stirring disk 18 formed on a return cut surface 16 inclined at a predetermined angle so as to be opposite to the feed cut surface 13 on the side opposite to the powder feeding direction and having stirring blades 17 on a rear end surface is provided. A large number are attached at a predetermined interval in a direction perpendicular to the axis. First stirring disk 15, stirring disk 1
Numerals 8 are alternately arranged in the axial direction of the hollow shafts 5 and 6 so as to be symmetrical with respect to the axis in the orthogonal direction. Between the first stirring disk 15 or the second stirring disk 18 on the hollow shaft 5
The stirring disk 15 or the second stirring disk 18 is arranged opposite to the first stirring disk 15 or the second stirring disk 18 on the hollow shaft 5. First stirring disk 1
5, the feed cut surface 14 and the return cut surface 16 of the second stirring disk 18 are cut at 45 ° with respect to the axis of the hollow shafts 5, 6 in this embodiment. However, the angle of the cut is not limited thereto, and may be in the range of 30 ° to 60 °.

The small gap between the first stirring disk 15 and the second stirring disk 18 is set to 5 to 10 mm, and
The stirring blade 15 of the stirring disk 15 and the second stirring disk 18
A small gap of 4.5 to 15 mm between the tip (outer peripheral surface) of each of 4, 4 and the outer peripheral surfaces of hollow shafts 5, 6 and the first stirring disk 1
5. The small gap between the tip (outer peripheral surface) of the stirring blades 14 and 17 of the second stirring disk 18 and the inner wall surface of the casing 1 is set to 5 to 1
Set to 5 mm. Thereby, the first stirring disk 1
5. Adhesive powder adheres little to the side surface of the second stirring disk 18, the outer peripheral surfaces of the hollow shafts 5, 6 and the inner wall surface of the casing 1, and even if it adheres, it can be easily peeled or scraped off. As a result, the contact between the first stirring disk 15, the second stirring disk 18, and the heat transfer surface of the inner wall surface of the casing 1 and the adhesive powder is constantly updated, and the heat transfer efficiency increases.

Rotary joints 19 and 20 are attached to the ends of the hollow shafts 5 and 6 protruding outside the casing 1, and heat medium (steam, hot water, etc.) is supplied from the rotary joint 19 to the hollow shafts 5 and 6. 1st transfer disk 7, 2nd transfer disk 8, 1st stirring disk 15, 2nd stirring disk 1
After returning to the inside of the hollow shafts 5, 6 from the first transfer disk 7, the second transfer disk 8, the first stirring disk 15, and the second stirring disk 18 through another communication hole (not shown), It is configured to be discharged from the joint 20. In this example, the rotary joint 19,
20 are provided at both ends of the hollow shafts 5 and 6, but provided only at one end of the hollow shafts 5 and 6, and the heat medium as described above is supplied to the first transfer disk 7, the second transfer disk 8, and the first transfer disk 8. The gas may flow into and out of the stirring disk 15 and the second stirring disk 18.

In the figures, reference numerals 21 and 22 denote hollow shafts 5,
Reference numeral 23 denotes a chain sprocket which meshes with each other and is mounted on the wheel 6. A chain (not shown) wound around the chain sprocket 23 is driven by an electric motor or the like to drive the hollow shaft 5 through the gears 21 and 22. 6 is rotated. 24 is a jacket 2
A heat medium supply pipe for supplying a heat medium into the inside;
26 is an inlet for feeding the carrier gas into the casing 1,
27 is the outlet, 28 is a supply port for the adhesive powder, and 29 is a discharge port for the dried powder.

A description will be given of the scraping action and the stirring and mixing action that affect the drying in the above embodiment. First, the two hollow shafts 5, 6 are supplied into the casing 1 from the supply port 28 while rotating in opposite directions. The adhered powder thus produced is transferred while being stirred by the cut surfaces 9 and 11 formed on the front end surfaces of the first transfer disk 7 and the second transfer disk 8 on the front half of the hollow shafts 5 and 6. ,
The hollow shafts 5 and 6 and the first transfer disk 7 and the second transfer disk 8 are heated and dried by the heat medium supplied into the hollow space. At this time, even if the adhesive powder adheres to the side surfaces of the first transfer disk 7 and the second transfer disk 8, the first transfer disk 7,
Since there is a small gap δ1 between the opposing side surfaces of the second transfer disk 8, the adhered adhered powder is scraped by the side surfaces of the disk once every rotation so that
That is, it is scraped off by the self-cleaning action. Further, a small clearance δ2 is formed between the outer peripheral surfaces of the first and second transfer disks 7 and 8 and the surfaces of the hollow shafts 5 and 6, and between the outer peripheral surfaces of the first and second transfer disks 7 and 8 and the inner surface of the casing 1. Because they are facing each other with δ3,
The adhesive powder is scraped off by the scraping action, and there is no adhesion of the adhesive powder to them. Therefore, the adhesive powder is efficiently preheat-dried.

Next, the adhesive powder pre-dried by the first transfer disk 7 and the second transfer disk 8 is
The first and second stirring disks 15 and 18 in the latter half of 6, that is, the reciprocating movement in the axial and radial directions by the feed cut surface 13 of the first stirring disk 15 and the return cut surface 16 of the second stirring disk 18. Is repeated, and a strong stirring and mixing action is performed, and a stirring action is performed by the stirring blades 14 and 17. Since the heat transfer coefficient of the adhesive powder subjected to such an action becomes extremely large, the hollow shaft 5,
6 and the first stirring disk 15 and the second stirring disk 18
The heating and drying is performed uniformly and with high efficiency by the heat medium supplied into the hollow.

In addition, since the first stirring disk 15 and the second stirring disk 18 are used for heating and drying the powder whose moisture content has been reduced by preliminary drying in the first half, the first and second stirring disks 15 and 18 are used. Side surfaces and outer peripheral surfaces of the disks 15, 18;
Adhesion to the surfaces of the hollow shafts 5 and 6 and the inner surface of the casing 1 is extremely small. Furthermore, since a large drying space can be taken in the casing 1 in the latter half, the drying effect can be enhanced accordingly. Since the first stirring disk 15 and the stirring disk 18 are provided on one hollow shaft 5 between the first stirring disk 15 and the second stirring disk 18 so as to face the other hollow shaft 6, Since there is no large dead space that causes the adhered powder to stay in the casing 1, stirring and mixing can be performed effectively. The powder (product) dried as described above is discharged from the discharge port 29. Further, the casing 1 is inclined downward by several degrees or less (preferably 2 °) from the supply port 28 side to the discharge port 29 side depending on the degree of moisture contained in the adhesive powder. Transfer can be performed smoothly.

[0019]

The present invention is embodied in the form described above, and has the following effects. A first transfer disk on a substantially front half in the axial direction of the hollow shaft;
Since the second transfer disk is provided, the adherence of the high-moisture adherent powder to the side surface of the transfer disk can be significantly reduced by the self-cleaning action and the scraping action. Adhesion to the surface and the surface of the hollow shaft and also to the inner surface of the casing can be reduced, so that preheating and drying can be performed efficiently and transfer can be ensured.

Further, the first shaft is disposed substantially on the rear half of the hollow shaft in the axial direction.
Since the stirring disk and the second stirring disk are provided, the adhesive powder can be positively stirred and mixed, so that the drying of the powder can be performed uniformly, and there is no variation in quality. A product can be obtained, and the drying efficiency can be greatly increased.

A first transfer disk and a second transfer disk are provided in a substantially front half of the same hollow shaft in one casing.
Since the first agitating disk and the second agitating disk are provided in substantially the rear half, the apparatus is compact.

Further, by inclining the casing 1 downward by several degrees from the supply port side to the discharge port side, the adhesive powder can be smoothly transferred.

[Brief description of the drawings]

FIG. 1 is a schematic front view, partially broken away, showing an embodiment of the present invention.

FIG. 2 is a schematic plan view of the above partly broken.

FIG. 3 is a longitudinal sectional view taken along line AA of FIG. 2;

FIG. 4 is a longitudinal sectional view taken along line BB in FIG. 2;

FIG. 5 is an enlarged sectional side view of the first and second transfer disks taken along line AA in FIG. 2;

FIG. 6 is an enlarged plan view of a main part of the first and second transfer disks, taken along line CC in FIG. 5;

FIG. 7 is an outer peripheral development view of the first and second transfer disks showing a mounting position of the first and second transfer disks with respect to the hollow shaft.

FIG. 8 is a partially broken perspective view showing a mounting position of first and second stirring disks with respect to a hollow shaft.

FIG. 9 is an enlarged cross-sectional plan view of a main part of the first and second stirring disks of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Double U-shaped casing 2 Jacket 3 Opening 5,6 Hollow shaft 7 First transfer disk 8 Second transfer disk 9,11 Cut surface inclined with respect to feed direction 10,12 Cut surface parallel with feed direction δ1 Slight Gap 13 Feed cut surface 14 Stirrer blade 15 First stirring disk 16 Return cut surface 17 Stirrer blade 18 Second stirring disk 28 Supply port 29 Discharge port

Claims (2)

[Claims] 1. A pair of hollow shafts rotating at the same speed in opposite directions to each other inside a casing having a supply port for adhering powder at one upper end and a discharge port for dried powder at the other lower end. A large number of hollow fan-shaped disks are arranged on both hollow shafts at regular intervals in the direction perpendicular to the axis of the hollow shaft, offset by a certain angle in the rotation direction, and communicated with the hollow interior of the hollow shaft. In the indirect heating type stirring and drying machine, the first and second transfer disks 7 and 8 are disposed on substantially the front half of the hollow shafts 5 and 6 in the axial direction, and the first stirring disk 15 is disposed on the substantially rear half thereof. , A second stirring disk 18, the first and second transfer disks 7, 8 are formed such that their outer peripheral surfaces are substantially parallel to the inner surface of the casing 1, and their front end surfaces in the rotational direction are inclined with respect to the feed direction. Formed on the feed cut surfaces 9 and 11 And the first and second transfer disks 7, 8 are arranged in the axial direction of the hollow shafts 5, 6, respectively.
The second transfer disk 8 on the other hollow shaft 5 is located between the first transfer disk 7 on the one hollow shaft 6 and the second transfer disk 8 on the other hollow shaft 5.
The first transfer disk 7 on one of the hollow shafts 6 is located between the transfer disks 8 between the opposing side surfaces of the first transfer disk 7 and the second transfer disk 8 and the outer peripheral surfaces of the first and second transfer disks 7 and 8. Small gaps δ 1 and δ 2 are formed between the outer surfaces of the first and second transfer disks 7 and 8 and the inner surfaces of the casing below the axis of the hollow shafts 5 and 6. A small gap δ3 is formed in the first stirring disk 15
A stirring blade 14 is formed on a feed cut surface 13 whose front end face in the rotation direction is inclined toward the feed direction of the adhesive powder with respect to the axial direction of the hollow shafts 5 and 6, and a stirring blade 14 is formed on the rear end face. 2 The front end face in the rotation direction of the stirring disk 18 is formed on the return cut face 16 inclined on the opposite side to the feed direction of the adhesive powder with respect to the axial direction of the hollow shafts 5 and 6, and the stirring blade 17 is formed on the rear end face. The first stirring disk 15 and the second stirring disk 18 are alternately arranged in the axial direction of each of the hollow shafts 5 and 6, and are arranged symmetrically with respect to the axis in the orthogonal direction. In the axial direction between the hollow shafts, the second stirring disk 15 on the other hollow shaft 5 is located between the first stirring disk 15 or the second stirring disk 18 on one hollow shaft 6.
An indirect heating type agitating / drying machine, wherein the agitating disk 18 or the first agitating disk 15 is arranged to face each other. 2. The indirect heating type agitator / dryer according to claim 1, wherein the casing is inclined downward by several degrees or less from the supply port side to the discharge port side.