JP5707332B2 - Push screw device and roll molding machine - Google Patents

Description

The present invention relates to a pressing screw device suitable for use in, for example, a roll molding machine that pressurizes a raw material obtained by kneading fine powder and a binder and molds it into a plate shape, and a roll molding machine equipped with the pressing screw device.
This application claims priority based on Japanese Patent Application No. 2010-095648 for which it applied to Japan on April 19, 2010, and uses the content here.

  Conventionally, a roll agglomerator has been used as an apparatus for pressurizing and molding a granulated raw material obtained by kneading fine powder and a binder. As shown in FIG. 4, the roll aggregator includes a molding roll 104 having a pair of fixed rolls 102 and movable rolls 103 each having an individual rotation axis. The fixed roll 102 is installed with its position fixed. On the other hand, the movable roll 103 receives a predetermined pressure from the hydraulic cylinder 106 and is pressed toward the fixed roll 102 side. A hopper 108 is provided above the molding roll 104. The hopper 108 includes a casing 111 and a push screw 112 disposed therein. The pushing screw 112 includes screw blades 114 formed in a spiral shape around the rotary drive shaft 113. Then, by rotating the pushing screw 112 by the driving force of the driving unit 115, the raw material 109 put in the casing 111 is supplied to the gap 105 between the fixed roll 102 and the movable roll 103, and the raw material 109 is screwed. Push down with blades 114. The raw material 109 pushed into the gap 105 receives a compressive force from the molding roll 104 and becomes a plate-shaped molded product 110.

  In addition to the above devices, a conventional screw conveyor that conveys powder particles and the like mainly in the horizontal direction by screw blades is disclosed in, for example, Patent Document 1 and the like.

  In a roll agglomerator, in order to transport a raw material kneaded with a binder such as tar having viscosity with respect to powdered coal or the like, when transporting with a plurality of screw blades wound spirally, between these screw blades The raw material tends to stay. However, in order to stably produce a molded product continuously, it is necessary to supply the raw material to the molding roll without depositing it between the screw blades. If the raw material adheres to and clogs between the screw blades, the raw material cannot be stably supplied. Therefore, an operation for removing the raw material clogged between the screw blades must be frequently performed.

  Patent Documents 2 and 3 disclose a screw conveyor provided with a plurality of screws. In Patent Document 2, the spiral direction and the rotation direction of each screw adjacent to each other are opposite to each other to prevent the conveyed product from adhering to the screw blades. In Patent Document 3, a plurality of screws having mutually opposite spiral winding directions and different pitches are rotated in the reverse direction at a rotation speed ratio that is the reverse of the ratio between the pitches of these screws, and the attached matter of the other screw. Scraping off.

  In the case of a roll agglomerator, it is necessary to press the raw material uniformly between the rolls in order to satisfy the quality requirements of the molded product such as high density and high strength. However, the techniques disclosed in Patent Documents 2 and 3 are configured in such a manner that the conveyed product is conveyed in the horizontal direction and discharged from the discharge port, and an operation of pressing the conveyed product by the screw blades cannot be obtained.

  Patent Document 4 discloses a push screw for a roll aggregator by the applicant of the present invention. This pushing screw is provided with screw blades having three kinds of inclination angles as the pitch becomes smaller in the conveying direction, and the raw material can be sufficiently pushed in while preventing the raw material from adhering.

Japanese Unexamined Patent Publication No. 7-304511 Japanese Unexamined Patent Publication No. 11-314728 Japanese Unexamined Patent Publication No. 2002-179235 Japanese Unexamined Patent Publication No. 2008-36692

  However, even in the push screw disclosed in Patent Document 4, the raw material tends to adhere and stagnate to the inner wall of the hopper casing, and the push screws provided at both ends are overloaded in order to scrape the raw material attached to the inner wall of the casing. There is a fear.

  This invention is made | formed in view of the said situation, Comprising: It aims at provision of the pressing machine which can extrude a raw material stably and uniformly, and the roll molding machine provided with this pressing screw apparatus.

In order to solve the above problems and achieve the object, the present invention employs the following means.
(1) A push screw device according to an aspect of the present invention includes a plurality of push screws that are disposed in a hopper and feed the raw material charged from the upper part of the hopper downward toward the hopper, and the push screws. Each of the push-in screws has a rotary drive shaft extending in the vertical direction, and screw blades formed in a spiral around the rotary drive shaft. The push-in screws are arranged so that the rotary drive shafts in a plan view are aligned along the same straight line; the vertical lower end positions of the screw blades are the same, and the screw blades The spiral winding directions are adjacent to each other in opposite directions; two of the push-in screws in the center of the alignment direction are set as a central screw, and the rotation drive shafts of the central screws have each When the portion is viewed in plan, the rotation direction of each screw blade and the feed direction of the raw material coincide with each other, and further, the screw blades of each of the central screws are arranged from above in the vertical direction to below. When viewed in a longitudinal section, the first conveying blade has a first inclination angle and sends the raw material downward in the vertical direction. A first consolidation for degassing a gas contained in the raw material sent from the first conveying blade while having a second inclination angle that is gentler than the first inclination angle when viewed in a longitudinal section; A blade having a third inclination angle that is looser than the second inclination angle when viewed in a longitudinal section, and a first material that pumps the raw material sent from the first compaction blade downward. In addition, when two of the side screws in the arrangement direction of the pushing screws are outer screws, the screw blades of each of the outer screws are moved from the upper side to the lower side in the vertical direction. A second conveying blade having a fourth inclination angle when viewed in a longitudinal section and feeding the raw material downward in the vertical direction; the fourth inclination angle when viewed in a longitudinal section Remote with a loose fifth inclination angle of the second pushing blades for pumping the material sent directly from the second conveying blade downward; comprises.

(2) In the above (1) , the second conveying blade is arranged so that the lower end is located at a position shifted from the upper end of the second pushing blade by 90 ° and upward in the rotation direction of the rotary drive shaft. You may employ | adopt the structure attached to the rotational drive shaft.
(3) In said (1) , you may employ | adopt the structure where the upper end height position of each said screw blade in each said outer screw is lower than the upper end height position of each said screw blade in each said center screw.
(4) A roll molding machine according to an aspect of the present invention includes a hopper having a casing for storing a raw material, and a pushing screw device that pushes the raw material in the casing downward; and the raw material extruded from the hopper. A pair of fixed rolls and a movable roll that are sandwiched and press-molded; and the push screw device is the push screw device according to any one of the above (1) to (3) , when viewed in plan The direction in which the pushing screws are arranged overlaps with the direction in which the gap between the fixed roll and the movable roll extends.

According to the pushing screw device of the present invention, the raw material can be extruded stably and uniformly. Thereby, for example, when this push screw device is applied to a roll molding machine (roll aggregating machine), a high-quality molded product can be molded in the molding roll.
According to the roll molding machine of the present invention, it is possible to obtain the same effect as the above-described push screw device.

It is a longitudinal cross-sectional view which shows schematic structure of the roll aggregator provided with the pushing screw apparatus which concerns on one Embodiment of this invention. It is a longitudinal cross-sectional view of the same pushing screw device. It is a figure which shows the same pushing screw apparatus, Comprising: It is the cross-sectional view seen from the BB line of FIG. It is a longitudinal cross-sectional view which shows schematic structure of the roll aggregator provided with the conventional pushing screw apparatus.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a push agitation device for a roll agglomerator (hereinafter referred to as a push screw device) according to an embodiment of the present invention and a roll agglomerator (a roll molding machine) provided with the same will be described with reference to the drawings. To do.

FIG. 1 is a longitudinal sectional view showing a schematic configuration of a roll aggregator 1 according to the present embodiment.
The roll aggregator 1 includes a hopper 8 having a casing 11 for storing the raw material 9 and a pushing screw device 12 for extruding the raw material 9 in the casing 11 downward; sandwiching the raw material 9 extruded from the hopper 8 A pair of fixed roll 2 and movable roll 3 that are pressure-molded with
The fixed roll 2 and the movable roll 3 of the roll aggregating machine 1 have rotating shafts 2a and 3a that are parallel to each other along the horizontal direction, and rotate inward in a plan view. In a state where the raw material 9 is supplied from above toward the gap 5 of the molding roll 4 composed of the pair of fixed rolls 2 and the movable roll 3, the movable roll 3 receives the urging force from the hydraulic cylinder 6 and is fixed. Rotate in the opposite direction to the fixed roll 2 while applying a constant pressing force toward the direction 2. As a result, the raw material 9 is pushed downward through the gap 5 while being pressurized by the fixed roll 2 and the movable roll 3. At that time, the movable roll 3 can continuously move along the direction of arrow A so that the pressure applied to the raw material 9 pushed into the gap 5 formed between the fixed roll 2 and the raw material 9 is maintained at a predetermined value. It is. And since the repulsive force from the raw material 9 is received when the movable roll 3 pressurizes, the width | variety of the clearance gap 5 spreads and the plate-shaped molded product 10 which has the thickness of the same dimension as the width | variety is shape | molded. A load cell 7 is attached to the fixed roll 2 and feedback control is performed to measure the pressing force by the hydraulic cylinder 6 and keep the pressure value constant.

A hopper 8 is provided above the gap 5 of the molding roll 4. The hopper 8 includes a casing 11 and a pushing screw device 12 disposed therein.
The pushing screw device 12 is arranged in the casing 11 of the hopper 8 and a plurality of pushing screws 12a to 12d for feeding the raw material 9 fed from the upper part of the hopper 8 downward to the hopper 8, and these pushing screws And a drive unit 15 (drive mechanism) that rotates the screws 12a to 12d.
Each push screw 12a-12d is arranged along with the extension direction of the clearance gap 5 along the upper direction. That is, the push screws 12 a to 12 d are arranged so that the rotary drive shafts 13 in a plan view are arranged on the same straight line along the extending direction of the gap 5. The number of the pushing screws 12a to 12d is two or more. If the molding roll 4 is large, one or more are provided symmetrically on both sides of the two provided at the center. Each pushing screw 12a-12d is provided with the rotational drive shaft 13 and the screw blade | wing 14 helically provided integrally in the circumference | surroundings. The raw material 9 put into the casing 11 can be pushed into the gap 5 of the molding roll 4 by rotating the push screw 14 integrally with the rotary drive shaft 13.

  As shown in FIG. 1, the upper ends of the rotary drive shafts 13 of the push-in screws 12 a to 12 d are connected to a drive unit 15 that rotates the rotary drive shafts 13 above the hopper 8. This drive part 15 is provided with the motor and speed reducer which are not shown in figure, for example. A raw material 9 obtained by kneading fine powder such as powdered coal having a particle diameter of 0.5 mm or less and a binder such as tar is supplied into the hopper 8 from a supply port 16 provided obliquely at the top of the hopper 8. Is done.

FIG. 2 shows the push screw device 12 of the present embodiment. In this push screw device 12, two push screws 12b and 12c are provided in the center of the arrangement direction, and push screws 12a and 12d are arranged one by one outside these push screws.
FIG. 3 is a plan sectional view of the four pushing screws 12a, 12b, 12c, and 12d shown in FIG. 2 as viewed from the line BB in FIG. 2, and shows the spiral of the screw blades 14a, 14b, 14c, and 14d. The winding direction and the rotation direction of the drive shaft 13 are indicated by arrows, respectively. The respective pushing screws 12a, 12b, 12c and 12d have the spiral winding directions opposite to each other between adjacent pushing screws, and the raw material 9 placed on the screw blades 14a, 14b, 14c and 14d is the tip of these pushing screws. That is, it rotates in the direction of being conveyed downward in the vertical direction. For example, as shown in FIG. 3, the pushing screw 12 b on the left side of the center two in FIG. 2 has a spiral screw blade 14 b wound counterclockwise as viewed from above the rotation drive shaft 13. Similarly, when the push screw 12b is rotated in the clockwise direction (in the direction of the arrow rb) as viewed from above, the raw material 9 moves downward along the screw blade 14b, and further, the raw material 9 is moved by the lower end surface 21 of the screw blade 14b. 9 is pressed toward the molding roll 4. That is, as shown in FIG. 3, the push-in screws 14b and 14d having a left-handed spiral shape when viewed from above are rotated clockwise in the direction of the arrow rb and rd when viewed from above (clockwise). The push-in screws 14a and 14c having a spiral shape are rotated counterclockwise (counterclockwise) in the directions of arrows ra and rc.

  Each of the rotary drive shafts 13 of the two push screws 12b and 12c (center screw) provided at the center position in the alignment direction (the center position in the axial direction of the molding roll 4) among the push screws 12a to 12d. Around the periphery, screw blades 14b and 14c are provided in which the inclination angle is changed from the upper end side toward the lower end side. The screw blades 14b and 14c of the central pushing screws 12b and 12c have the same pitch interval and have a spiral shape wound in the opposite direction, and are mutually inward when viewed from the supply port 16 of the hopper 8. Rotate in the opposite direction. That is, as shown in FIG. 3, when the raw material 9 is supplied from the upper side of the paper, when viewed from the raw material supply side, the raw material 9 is rotated in a direction approaching each other's pushing screw to move the raw material 9 between the screw blades 14 b and 14 c. Can be taken in efficiently. More specifically, when the portion between the rotary drive shafts 13 of the screws 12b and 12c is viewed in plan as shown in FIG. 3, the rotational direction of the screw blades 14b and 14c and the supply direction of the raw material 9 are determined. Match. Therefore, when viewed from the raw material 9 supplied from the upper side of the hopper 8, the entrance between the central screw blades 14b and 14c is wide, and the entrance gradually narrows as the gap between the screw blades 14b and 14c approaches. It is like that. In addition, the screw blades 14b and 14c rotate inward to each other so that the raw material 9 is fed while being guided in a direction in which the opening is narrowed. Therefore, the raw material 9 can be efficiently taken in between the screw blades 14b and 14c.

Further, the screw blades 14b and 14c of the central push-in screws 12b and 12c have a smaller inclination angle from the upper end to the lower end side of the respective rotary drive shafts 13. That is, each of the screw blades 14b and 14c has a large inclination angle (first inclination angle) when viewed in a longitudinal section, and feeds the raw material 9 below the hopper 8 (downward in the vertical direction). A conveying blade); and a medium inclination angle (second inclination angle) that is looser than a large inclination angle when viewed in a longitudinal section, and is a compact that degass the gas contained in the raw material 9 conveyed from the conveying blade 22 A blade 23 (first compacted blade); having a small tilt angle (third tilt angle) that is gentler than the medium tilt angle when viewed in a longitudinal section, and for molding the raw material 9 sent from the compacted blade 23 The pushing blades 24 (first pushing blades) for applying a pushing force to the roll 4 are sequentially formed on the outer periphery of the rotary drive shaft 13 by one turn.
The inclination angle θ1 of the pushing blade 24 is 10 ° to 15 °, the inclination angle θ2 of the compacting blade 23 is 1.5 to 2.5 times the inclination angle θ1 of the pushing blade 24, and the inclination angle θ3 of the conveying blade 22 is It is preferably more than 2.5 times and less than 3.5 times the inclination angle θ1 of the pushing blade 24. Note that the inclination angles θ <b> 1 to θ <b> 3 are all inclination angles with respect to a plane orthogonal to the rotational drive shaft 13.
As described above, since the central push screws 12b and 12c rotate in the direction of conveying the raw material 9 downward, the raw material 9 supplied to the hopper 8 through the supply port 16 is fed to the central push screws 12b and 12c. By the rotation, the sheet is first sent to the lower side of the hopper 8 by the conveying blade 22. Subsequently, the raw material 9 after passing through the conveying blade 22 is pushed into the gap 5 (FIG. 1) of the molding roll 4 by the lower end surface 21 of the pushing blade 24 after the voids in the raw material are removed by the compacting blade 23. . At this time, the vertical direction lower end positions of the screw blades 14a to 14d are the same, and the spiral winding directions of the screw blades 14a to 14d are opposite to each other. In addition, the raw material 9 can be pushed out with a force of uniform distribution along the direction in which the push screws 12a to 12d are arranged.
In addition, at the same time when the raw material 9 is transported, the raw material 9 is stably supplied, degassed, and pressurized by the transport blades 22, the compaction blades 23, and the pushing blades 24 each having a unique inclination angle. In addition, since the raw material 9 is conveyed while increasing the degree of compression toward the lower side, the raw material 9 hardly adheres between the screw blades 14 b and 14 c, and the raw material 9 is stabilized toward the gap 5 of the molding roll 4. And pushed.

The pushing screws 12a and 12d (the two outside screws on the both ends in the arrangement direction of the pushing screws 12a to 12d) provided on both outer sides of the center pushing screws 12b and 12c are respectively pushed in the adjacent center. The screws 12b and 12c have spiral screw blades 14a and 14d wound in opposite directions.
The outer pressing screws 12a and 12d do not include the compacting blade 23 of the central pressing screws 12b and 12c between them, and the conveying blade 22 and the rotation blade 13 extend from the upper end toward the lower end. Only the pushing blades 24 are provided. That is, each of the screw blades 14a and 14d included in each of the pushing screws 12a and 12d has the same inclination angle (fourth inclination angle) as the large inclination angle from the upper side to the lower side in the vertical direction, and the raw material 9 is vertically A transport blade 22 (second transport blade) that feeds downward in the direction; having the same tilt angle as the small tilt angle (a fifth tilt angle that is looser than the fourth tilt angle), and from the transport blade 22 A pushing blade 24 (second pushing blade) that feeds the raw material 9 that has been sent directly downward.
Further, the lower end of the conveying blade 22 relatively on the upper stage side is 90 ° from the upper end of the pushing blade 24 on the lower stage side in the rotation direction of the rotary drive shaft 13, that is, 1 / around the rotary drive shaft 13. It is shifted upward by 4 rounds. In this way, by omitting the compacting blades 23 of the outer pushing screws 12a and 12d, the raw material 9 does not become congested in the vicinity of the side wall 31 of the casing 11 facing these pushing screws 12a and 12d. As a result, since the resistance received when the raw material 9 descends while sliding on the side wall 31 can be reduced, overloading of the outer pushing screws 12a and 12d can be suppressed. Further, the height position of the conveying blades 22 of the outer pushing screws 12a, 12d is shifted from the height position of the conveying blades 22 of the central pushing screws 12b, 12c (more specifically, the outer pushing screws 12a, 12d Since the upper end height position of the conveying blade 22 is lower than the upper end height position of the conveying blade 22 of the central push screw 12b, 12c), it is possible to suppress the raw material 9 from adhering to the side wall 31 of the casing 11, It becomes easy to convey the raw material 9 smoothly downward.

  The lower ends of the pushing blades 24 of the central pushing screws 12b and 12c and the outer pushing screws 12a and 12d are all at substantially the same height direction position, and the raw material 9 is uniformly formed by the lower end surface 21 of each pushing blade 24. Press toward 4.

  According to the pushing screw device 12 having the above-described structure, the raw material 9 is prevented from adhering to the screw blades 14 (14a to 14d) and the side wall 31 inside the casing 11, and the raw material 9 is supplied to the molding roll 4. The raw material 9 can be uniformly pressed against the molding roll 4 side.

  The number of the pushing screws 12a to 12d is not limited to four, but in order to press the raw material 9 so that the distribution along the axial direction of the molding roll 4 is uniform, it is preferable that the number is an even number. . In the case of two, only the two central pushing screws 12b and 12c may be provided in the above embodiment.

  As mentioned above, although preferred embodiment of this invention was described, this invention is not limited only to this example. It is obvious for those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs to.

  The present invention can be suitably applied to, for example, a roll aggregator that pressurizes a raw material obtained by kneading fine powder and a binder and molds the raw material into a plate shape.

1 Agglomeration machine (roll molding machine)
2 fixed roll 3 movable roll 4 molding roll 5 gap 8 hopper 9 raw material 10 molded product 11 casing 12 pushing screw device 12a, 12d outside pushing screw (outside screw)
12b, 12c Center push screw (central screw)
13 Rotation Drive Shaft 14 (14a, 14b, 14c, 14d) Screw Blade 15 Drive Unit (Drive Mechanism)
16 Supply port 22 Conveying blade (first conveying blade, second conveying blade)
23 Consolidation blade (first consolidation blade)
24 Pushing blade (first pushing blade, second pushing blade)

Claims (4)

A plurality of push-in screws arranged in the hopper and pumping the raw material charged from the upper part of the hopper downward, and a drive mechanism for rotating the push-screws. Is a pushing screw device having a rotary drive shaft extending along the vertical direction and screw blades formed in a spiral around the rotary drive shaft,
The push screws are arranged so that the rotary drive shafts in a plan view are arranged along the same straight line;
The vertical direction lower end positions of the screw blades are the same as each other, and the spiral winding directions of the screw blades are adjacent to each other and are opposite to each other;
Two of the push-in screws in the center of the alignment direction are set as a central screw, and when the portion between the rotary drive shafts of the central screw is viewed in plan view, the rotation direction of the screw blades, The supply direction of the raw materials is the same,
further,
Each of the screw blades of each of the central screws, from the vertical direction upward to downward,
A first conveying blade having a first inclination angle when viewed in a longitudinal section and feeding the raw material downward in the vertical direction;
A first compression blade having a second inclination angle that is looser than the first inclination angle when viewed in a longitudinal section and degassing the gas contained in the raw material sent from the first conveying blade When;
A first pushing blade that has a third inclination angle that is looser than the second inclination angle when viewed in a longitudinal section, and that pumps the raw material sent from the first compaction blade downward. ;
With
Moreover,
When two of the side screws in the arrangement direction of the push-in screws are outer screws, the screw blades of the outer screws are provided from the upper side to the lower side in the vertical direction.
A second conveying blade having a fourth inclination angle when viewed in a longitudinal section and feeding the raw material downward in the vertical direction;
A second pushing blade that has a fifth inclination angle that is gentler than the fourth inclination angle when viewed in a longitudinal section, and that pumps the raw material directly sent from the second conveying blade downward. When;
Pushing screw machine, characterized in that it comprises a. The second conveying blade is attached to the rotary drive shaft so that the lower end is positioned 90 ° upward from the upper end of the second push blade in the rotational direction of the rotary drive shaft. The pushing screw device according to claim 1 . The pushing screw device according to claim 1 , wherein an upper end height position of each screw blade in each outer screw is lower than an upper end height position of each screw blade in each central screw. A casing for storing the raw material, and a hopper having a pushing screw device for extruding the raw material in the casing downward;
A pair of fixed rolls and movable rolls that sandwich and press-mold the raw material extruded from the hopper;
With
The push screw device is the push screw device according to any one of claims 1 to 3 ,
A roll molding machine, characterized in that a direction in which the push screws are arranged in a plan view overlaps with an extending direction of a gap between the fixed roll and the movable roll.

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