JP4601055B2 - Classifier - Google Patents

Description

  The present invention includes a classification rotor that is formed of a cylindrical body having a plurality of classification blades on the outer peripheral portion and that has an opening formed on at least one side surface in a direction along the cylinder axis, and the classification rotor is accommodated And a main body that holds the powder to be classified from the outside and supplies it to the outer peripheral portion of the classification rotor, and a tip side portion of the rotor from the opening on the side surface of the classification rotor. The present invention relates to a classifier provided with a discharge flow path portion that is arranged so as to enter inside and sucks the powder that has passed through the classification blade from the tip side and discharges the powder to the outside.

  In the classifier described above, the flow path diameter (inner diameter) of the tip side portion of the discharge flow path portion arranged so as to enter the inside of the classification rotor affects the classification point, and the classification point becomes smaller when the flow path diameter becomes smaller (that is, , The particle size of the classified powder becomes smaller). On the other hand, the tip side portion of the discharge channel part is the part where the channel diameter becomes the narrowest, and the tip side part of the discharge channel part is swung while increasing the speed of the powder that has passed through the classification blade within the classifying rotor. Passes towards the discharge side. For this reason, friction between the inner wall of the tip side portion and the passing powder increases, and wear of the inner wall and adhesion of the powder to the inner wall are likely to occur. As a result, in the front end portion of the discharge flow path portion, classification point fluctuations due to changes in flow path diameter, member breakage, clogging with powder, etc. may occur, which may impede classification processing.

  Therefore, conventionally, by attaching the tip side portion of the discharge channel part to the classification rotor side and rotating integrally with the classifying rotor, the powder passing in a swiveling state and the inner wall of the tip side part of the discharge channel part are There has been proposed a classifier in which the relative speed difference is reduced to suppress wear on the inner wall of the front end side portion of the discharge flow path portion and adhesion of powder (see, for example, Patent Document 1).

JP 2002-355612 A

  However, in the conventional classifier described in Patent Document 1, wear and adhesion caused by collision of powder passing through the flow path at the tip end portion of the discharge flow path portion with the flow path inner wall are further suppressed. Therefore, further improvement is desired.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to use a powder flow that passes in a swirling state through the flow path at the tip end portion of the discharge flow path section by technical means different from the conventional one. An object of the present invention is to provide a classifier capable of effectively suppressing wear on a road wall and adhesion of powder.

The first characteristic configuration of the classifier for realizing the above object is that the distal end side portion of the discharge flow path portion is formed in a substantially tapered shape whose opening diameter gradually expands from the distal end side toward the discharge side . It is in.

With the above configuration, the tip side portion of the discharge channel portion formed in a substantially tapered extended channel shape in which the inner diameter increases toward the discharge side while the powder that has passed through the classification blade swirls inside the classification rotor When passing, the collision angle between the direction of the powder colliding with the inner wall of the flow path and the wall surface becomes smaller than that in the case of the front end portion of the straight flow path shape having the same inner diameter toward the discharge side, for example. . As a result, the impact received from the impinging powder on the inner wall of the discharge channel is reduced, and the friction between the inner wall and the passing powder is reduced. It is difficult for the powder to adhere to the inner wall.
Therefore, the wear of the inner wall of the flow path and the adhesion of the powder due to the powder passing through the flow path at the tip end portion of the discharge flow path portion in a swivel state can be effectively suppressed by technical means different from the conventional one. A classifier is provided.

With the above configuration, the powder collision angle with the inner wall of the flow path is almost the same until the powder that has passed through the classification blades has passed through the distal end portion of the discharge flow path portion formed in a substantially tapered extended flow path shape. The angle becomes a small angle, and the state in which the friction between the inner wall of the flow path and the passing powder is small continues stably. Here, the substantially tapered shape includes all shapes such as a curved surface shape whose opening diameter gradually expands from the tip side toward the discharge side. The tapered shape is a simple shape and is easy and practical to process.
Therefore, a practical and preferred embodiment of the classifier according to the above configuration is provided.

The second characteristic configuration is that, in the first characteristic configuration, at least the tip side portion of the discharge flow path portion is attached to the classification rotor so as to be integrally rotatable.
With the above configuration, at least the tip side portion of the discharge channel portion is attached to the classifying rotor and rotates integrally with the classifying rotor, so that the powder passing in a swiveling state and the channel inner wall of the tip side portion of the discharge channel portion As a result, the effect of suppressing wear on the inner wall of the flow path and adhesion of powder can be obtained. At the same time, since the disturbance of the swirling flow inside the classification rotor is reduced by the integral rotation of the tip side portion and the classification rotor, the classification point can be lowered to achieve a sharper classification accuracy.
Therefore, it is possible to obtain a greater effect that combines both the effect of the expanded flow channel shape and the effect of lowering the relative speed difference with respect to the wear of the inner wall of the front end portion of the discharge flow channel and the adhesion of powder. A preferred embodiment of the machine is provided.

Hereinafter, embodiments of the classifier of the present invention will be described.
As shown in FIGS. 1 and 2 (note that a sectional view of the classifying rotor 2 at the II-II position in FIG. 1 is shown in FIG. 2), the classifier of the present invention has a plurality of classifying blades 3 on the outer periphery. A classifying rotor 2 that is formed of a cylinder and has an opening 4 formed on one side surface in a direction along the axis X of the cylinder, and the classifying rotor 2 are accommodated to be rotatable around the axis X of the cylinder The main body 1 that holds the powder F to be classified from the outside and supplies it to the outer peripheral portion of the classification rotor 2 and the front end side portion 5 c enter the rotor through the opening 4 on one side surface of the classification rotor 2. And a discharge flow path portion 5 that sucks the powder F that has passed through the classification blade 3 from the tip side and discharges the powder F to the outside. That is, the air inside the classification rotor 2 is sucked through the discharge flow path portion 5, and the particles F having a predetermined particle size are selected from the powder F to be classified and taken out to the outside of the main body 1. It is. Hereinafter, each part will be described in order.

  The inside of the main body 1 serves as a processing chamber 6 for classifying the powder F introduced from the outside. FIG. 1 mainly shows only a portion where the classification rotor 2 is provided, and other portions such as an introduction portion of the powder F from the outside are omitted. The lid 7 is for maintenance / inspection of the classification rotor 2.

  The classification rotor 2 is provided in the processing chamber 6 in the form of a so-called horizontally arranged classification rotor that rotates around a rotation axis X in the horizontal direction. The classification rotor 2 is rotated at a high speed by a drive motor 8 provided outside the processing chamber 6, and the rotation speed can be changed as appropriate. In this embodiment, although the example provided with the flat plate-shaped classification blade 3 is shown, these classification blade 3 is attached at the angle which includes the rotating shaft core X in the extension plane of the plate surface. In addition, although illustration is abbreviate | omitted, you may attach diagonally with respect to the radial direction so that it may be in the state which does not include the rotating shaft core X in the extension plane of the classification blade 3 plate surface. Moreover, the shape of the classification blade 3 is not simply a flat plate shape, but may be configured to be an inclined shape or a curved shape. Further, the classifying rotor 2 may be arranged vertically with the same configuration.

  Air in the processing chamber 6 of the main body 1 is sucked by the suction means (not shown) from the classification rotor 2 through the discharge flow path portion 5. As a result, when the air inside the processing chamber 6 is drawn into the classification rotor 2 through each of the classification blades 3 of the classification rotor 2 that rotates at high speed, particles having a predetermined particle size or less are classified into the classification rotor. On the other hand, particles having an excessive particle size are prevented from flowing into the classification rotor 2 by the rotating classification blade 3. In this way, for example, fine powder having a particle size of about several μm to several tens of μm can be classified. The powder classified by the classification rotor 2 is discharged by the discharge flow path section 5, and then guided to a collecting means such as a bag filter and taken out as a product. As the suction means, for example, a general blower or the like can be used. The suction strength can be changed freely. For example, the amount of air to be sucked is changed as appropriate by changing the rotation speed of the suction fan or by using a flow rate adjusting valve.

Further, the flow passage inner diameter D1 of the tip side portion 5c of the discharge flow passage section 5 entering the classification rotor 2 is configured to be minimum, and the classification point is set by the flow passage inner diameter D1. Furthermore, the tip side portion of the discharge channel portion 5 is formed in an expanded channel shape, specifically a taper shape, whose inner diameter increases from the tip toward the discharge side. As a result, as shown in FIG. 3, when the powder F taken into the classification rotor 2 passes around the distal end side portion 5 c of the discharge flow channel portion 5 while turning around the cylindrical axis X, the flow channel inner wall Is smaller than the angle K2 in the case of a linear flow path inner wall (indicated by a dotted line in the figure), and wear of the flow path inner wall, powder adhesion, and the like are prevented.

  Further, at least the distal end side portion 5 c in the discharge flow path portion 5 is attached to the classification rotor 2 so as to be integrally rotatable. That is, the discharge flow path part 5 is comprised by the front end side part 5c attached to the classification rotor 2, and the cylindrical member 5a provided separately from the said front end side part 5c. In this configuration, since the tip side portion 5c rotates with the classification rotor 2, the powder F passing through the classification blade 3 and riding on the suction air forming a spiral flow inside the classification rotor 2 is transferred to the tip side portion. Rotates at substantially the same angular velocity as 5c. As a result, the degree of friction between the powder F and the inner wall of the tip end portion 5c is reduced, and the tip end portion 5c can be prevented from being worn. Note that the tip end portion 5c of the discharge flow path portion 5 and the inner surface of the cylindrical member 5a may be surface-treated to lower the friction coefficient, thereby further enhancing the effect of preventing wear, powder adhesion, and the like. For example, as the surface treatment, the inner surface can be subjected to buffing, electrolytic polishing, fluorine resin coating, or various plating treatments.

  Further, in FIG. 1, a seal air supply portion 9 for supplying seal air A to seal the gap between the distal end side portion 5c of the discharge flow path portion 5 and the cylindrical member 5a is provided on the outer periphery of the cylindrical member 5a. The part is provided in an annular shape.

[Another embodiment]
In the above-described embodiment, the opening 4 is provided only on one side surface in the direction along the cylinder axis of the cylindrical classification rotor 2, and the distal end side portion 5 c of the discharge flow path portion 5 is arranged to enter the opening 4. However, the openings 4 are provided on both surfaces of the cylindrical classification rotor 2 in the direction along the cylinder axis, and the openings 4 are arranged so that the front end side portions of the discharge flow path portion 5 enter the openings 4. The classified powder may be discharged from the surface.

  In the said embodiment, although it formed in the taper shape as an extended flow path shape of the front end side part 5c of the discharge flow path part 5, as shown to (b)-(d) of other shapes, for example, FIG. It may be formed into a thing. (A) is a basic type in which the distal end side portion 5c of the discharge flow path portion 5 is tapered, and (B) is the end of the distal end side portion 5c of (B) in the tapered extension portion side. Only the part is formed in a curved surface shape, (C) is the one in which the tip side portion 5c is formed in a curved shape from the tip part of the opening toward the end part on the extension part side, (D) is The tip of the tip side portion 5c is further formed into a curved surface in the form of (c). In this way, by making a part of the inner surface and the entire inner surface of the distal end side portion 5c into a curved surface, air flow can be sucked, discharged, and distributed smoothly, pressure loss can be reduced, and powder adherence to the inner surface and wear can be prevented. The effect of can be obtained more reliably.

  In the above embodiment, only the distal end portion 5c of the expanded flow channel shape in the discharge flow channel portion 5 is attached to the classification rotor 2 and is configured to rotate integrally with the classification rotor 2, but the entire discharge flow channel portion 5 is configured. May be attached to the classifying rotor 2 so that the entire discharge flow path portion 5 is integrally rotated with the classifying rotor 2. In addition, you may arrange | position in the fixed state, without attaching the discharge flow path part 5 containing the front end side part 5c of an extended flow path shape to the classification rotor 2. FIG.

  The classifier according to the present invention has problems such as wear on the inner wall of the flow path due to powder collision and adhesion of powder when the powder to be classified flows from the classification rotor to the tip side portion of the discharge flow path. Since it is effectively prevented, it can be suitably applied to various powder classifiers without any trouble. In that case, it can also be used as an apparatus of a classifier alone, or can be used as a part of an apparatus having other functions. For example, the classifier may be provided in a part of the pulverizer, and the powder pulverization process and the classification process may be performed continuously.

Front sectional view showing the structure of the classifier according to the present invention Side surface sectional view showing the structure of the classifier according to the present invention Front side view showing the operation of the classifier of the present invention Front sectional view showing the structure of the classification rotor according to the present invention

DESCRIPTION OF SYMBOLS 1 Main body 2 Classifying rotor 3 Classifying blade 4 Opening 5 Discharge flow path part 5a Cylindrical member 5c Tip side part 6 Processing chamber 7 Cover body 8 Motor 9 Seal air supply part A Seal air F Powder X Tube axis

Claims (2)

A classifying rotor that is composed of a cylinder having a plurality of classifying blades on the outer peripheral portion, and that has an opening formed on at least one side surface of both side surfaces in the direction along the cylinder axis;
A main body that accommodates the classification rotor and holds it rotatably around a cylindrical axis, and that introduces powder to be classified from the outside and supplies it to the outer periphery of the classification rotor;
A classification provided with a discharge flow path portion in which the tip side portion is arranged so as to enter the rotor through the opening on the side surface of the classification rotor, and sucks the powder that has passed through the classification blade from the tip side and discharges it to the outside. Machine,
A classifier in which a distal end side portion of the discharge flow path portion is formed in a substantially tapered shape whose opening diameter gradually expands from the distal end side toward the discharge side . The classifier according to claim 1, wherein at least the tip side portion of the discharge flow path portion is attached to the classification rotor so as to be integrally rotatable.

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