JP2006027031A - Apparatus for cooling cylinder of resin extruder and method for cooling cylinder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the cooling nonuniformity in the peripheral direction of a cylinder while compact properties is kept good in an apparatus for cooling the cylinder of a resin extruder. <P>SOLUTION: A sleeve 3 is formed to surround the cylinder 2, and an air inlet 4 and an air outlet 5 are formed in the sleeve 3. A blower 6 for supplying air is connected to the air inlet 4. A cylindrical space 7 formed between the cylinder 2 and the sleeve 3 is partitioned in the axial direction of the cylinder by screens 11-15. An air circulation opening 8 is opened in each of the screens 11-15. The air circulation openings 8 of the adjacent screens are arranged alternately, and air is made to flow in the peripheral direction in spaces R2-R5 held between the screens 11-15. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an apparatus and a method for cooling a cylinder in a resin extruder.

  This type of cooling device is disclosed in FIG. In FIG. 1 of Patent Document 1, a cylinder of an extruder installed with its axis oriented horizontally is covered by an enclosure, and cold air is supplied from the lower surface of the enclosure by a blower. The air supplied to the inside of the enclosure circulates on both sides of the cylinder while passing through the cooling zone, and is discharged through an outlet made at the top of the enclosure.

Patent Document 1 discloses the following configuration, pointing out that the cooling efficiency at the top of the cylinder is lower than that at the bottom due to the so-called chimney effect in the above configuration. That is, as shown in FIG. 2 or FIG. 3 of Patent Document 1, an air outlet is provided at a position different from the position of the blower in the cylinder axial direction and on the bottom surface of the enclosure. As a result, the air supplied from the blower to the inside of the enclosure is dispersed on the outer periphery of the cylinder by the baffle, and then flows in the vertical direction (cylinder axial direction) along the cylinder portion and is discharged from the outlet. The That is, an air flow in the cylinder axial direction is formed over the entire length of the cooling zone formed by the enclosure. Patent Document 1 assumes that the temperature can be made uniform over the cross section of the cylinder by adopting the above-described configuration, and wear and breakage of the extrusion screw and the cylinder can be greatly reduced.
JP-A-6-254944 (FIG. 1, paragraph number 0003, FIG. 2 and FIG. 3, paragraph numbers 0013 and 0014)

  However, in the configuration of FIG. 2 or FIG. 3 of the above-mentioned Patent Document 1, when the axial flow velocity of the cooling air is made equal between the upper part and the lower part of the cylinder, the air flows into the part where the air flows from the blower inside the enclosure. A header is required. Therefore, although the chimney effect can be avoided and the cylinder can be cooled to some extent in the circumferential direction, it has been difficult to make the enclosure compact.

  Moreover, it is difficult to say that the cooling efficiency of the cylinder is sufficiently good simply by forming an air flow in the cylinder axial direction as shown in FIGS. In this regard, FIG. 4 of Patent Document 1 discloses a configuration in which cooling fins are provided on the outer periphery of the cylinder. However, the addition of the auxiliary heat exchange means increases the manufacturing cost and the number of assembling steps and reduces the cooling time. The enclosure will be enlarged to secure the fin mounting space.

Means and effects for solving the problems

  The problems to be solved by the present invention are as described above. Next, means for solving the problems and the effects thereof will be described.

  ◆ According to a first aspect of the present invention, a cylinder cooling device for a resin extruder, a sleeve surrounding a cylinder, an air inlet and an air outlet provided in the sleeve, and a blower for supplying air from the air inlet And cooling the cylinder of the resin extruder, comprising: at least one partition plate that partitions the space between the cylinder and the sleeve in the cylinder axial direction; and an air circulation port that is open to the partition plate. An apparatus is provided.

  Thereby, the flow of the circumferential direction of a cylinder can be actively formed in the space between a cylinder and a sleeve with a partition plate. As a result, with a compact configuration, it is possible to achieve a configuration in which uneven cooling in the circumferential direction of the cylinder hardly occurs. Moreover, since the flow rate increases as the flow path becomes narrower by the partition plate, the cooling efficiency can be improved. Therefore, it is possible to reduce the necessity for providing auxiliary heat exchange means, and to achieve a compact configuration in which cost and manufacturing man-hours can be easily reduced.

  In the cylinder cooling device for the resin extruder, a plurality of the partition plates are provided, and a flow passage cross-sectional area obtained by cutting an air flow passage sandwiched between adjacent partition plates by a plane including the cylinder shaft is S1, It is preferable that S1 <S2, where S2 is a cross-sectional area of the air channel cut by a plane perpendicular to the cylinder axis.

  Thereby, in the air flow path sandwiched between the partition plates, the circumferential flow velocity of the air can be made larger than the axial flow velocity (a circumferential air flow can be reliably formed). Therefore, the uneven cooling in the circumferential direction of the cylinder can be reduced more reliably.

  In the cylinder cooling device for the resin extruder, it is preferable that S1 <0.5 × S2.

  Thereby, the flow velocity in the circumferential direction of air can be further increased, and uneven cooling in the circumferential direction of the cylinder can be reliably reduced.

  In the cylinder cooling device for the resin extruder, the ratio of the opening area of the air circulation port of the partition plate is preferably 30% or more and 50% or less.

  Thus, the cooling air can be smoothly passed from the air inlet to the air outlet at the same time as the circumferential flow of air in the sleeve is reliably formed.

  In the cylinder cooling device of the resin extruder, it is preferable that the partition plate is provided so as to contact the outer peripheral surface of the cylinder.

  Thereby, the partition plate that guides the air flow can also serve as a cooling fin, and the cooling efficiency can be improved with a simple configuration.

  In the cylinder cooling device of the resin extruder, it is preferable that the partition plate is configured as an arc-shaped plate with a portion corresponding to the air circulation port cut out.

  Thereby, the circulation of air through the air circulation port becomes smooth, and the cooling efficiency is further improved.

  In the cylinder cooling device for the resin extruder, it is preferable that a plurality of the partition plates are provided and the air circulation ports of adjacent partition plates are arranged at positions that do not overlap each other.

  Thereby, in the space pinched | interposed by each partition plate, air can be reliably flowed from the air circulation port to the air circulation port in the circumferential direction. As a result, the uneven cooling in the circumferential direction of the cylinder is further reduced.

  In the cylinder cooling device for the resin extruder, it is preferable that the air circulation ports of adjacent partition plates are provided alternately with the cylinder shaft in between.

  “Alternately provided” means that the air circulation ports are provided so as to have an angle difference of 150 ° or more and 210 ° or less.

  Thereby, in the space pinched | interposed by each partition plate, air can be reliably flowed from the air circulation port to the air circulation port in the circumferential direction. As a result, the uneven cooling in the circumferential direction of the cylinder is further reduced.

  ◆ According to a second aspect of the present invention, there is provided a cylinder cooling method for a resin extruder, wherein a sleeve is provided so as to surround the cylinder, and a space between the cylinder and the sleeve is partially formed in a cylinder axial direction. After providing at least one partition plate so as to partition, air is supplied into the sleeve from an air inlet provided in the sleeve, and this air is supplied to the sleeve, the cylinder, and the partition plate. There is provided a cylinder cooling method for a resin extruder, which is discharged from an air outlet provided in the sleeve after passing through a path.

  Thereby, the flow of the circumferential direction of a cylinder can be actively formed in the space between a cylinder and a sleeve with a partition plate. As a result, with a compact configuration, it is possible to achieve a configuration in which uneven cooling in the circumferential direction of the cylinder hardly occurs. Moreover, since the flow rate increases as the flow path becomes narrower by the partition plate, the cooling efficiency can be improved. Therefore, the necessity for providing auxiliary heat exchange means can be reduced, and the cost and the number of manufacturing steps can be easily reduced and the configuration can be made compact.

  ◆ In the cylinder cooling method of the resin extruder, a plurality of the partition plates are provided, and a flow path cross-sectional area obtained by cutting an air flow path sandwiched between adjacent partition plates by a plane including the cylinder shaft is S1, It is preferable that S1 <S2, where S2 is a cross-sectional area of the air channel cut by a plane perpendicular to the cylinder axis.

  Thereby, in the air flow path sandwiched between the partition plates, the circumferential flow velocity of the air can be made larger than the axial flow velocity (a circumferential air flow can be reliably formed). Therefore, the uneven cooling in the circumferential direction of the cylinder can be reduced more reliably.

  Next, embodiments of the invention will be described. 1 is a perspective view showing an overall configuration of a cylinder cooling device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1, and FIG. 3 is a diagram showing a configuration of a partition plate. is there.

  1 and 2, the cooling device 1 is attached to a cylinder 2 of an extrusion device arranged with its axis oriented horizontally. The cylinder 2 is filled with a resin that is heated and fluidized, and the resin is extruded in the axial direction of the cylinder by an unillustrated extrusion screw.

  The cooling device 1 includes a bottomed cylindrical sleeve 3 that surrounds a part of the length of the cylinder 2. A cylindrical space 7 is formed inside the sleeve 3 (between the outer peripheral surface of the cylinder 2 and the inner peripheral surface of the sleeve 3), and a region corresponding to the cylindrical space 7 is a cooling zone. An air inlet 4 is formed at the bottom of one end of the sleeve 3 in the axial direction, and an air outlet 5 is formed at the bottom of the other end in the axial direction. A blower 6 as air supply means is connected to the air inlet 4 so that low-temperature air can be introduced into the cylindrical space 7 through the air inlet 4.

  Inside the sleeve 3, five partition plates 11 to 15 are installed so as to partition the cylindrical space 7 in the cylinder axial direction. The cylindrical space 7 is partitioned by the partition plates 11 to 15 into six annular spaces R1 to R6 arranged in the cylinder axial direction. Although the shape of the partition plate 11 is shown in FIG. 3 as a representative, the partition plate 11 is configured as an arc-shaped flat plate perpendicular to the cylinder axis. As shown in FIGS. 1 and 3, the partition plate 11 has a shape like a donut cut out in an arc shape or a fan shape, and the cut out portion constitutes an air circulation port 8. ing. In addition, the five partition plates 11-15 are comprised in the same shape. The partition plates 11 to 15 are attached to the cylinder 2 and the sleeve 3 with their inner peripheral edges in contact with the outer peripheral surface of the cylinder 2.

  In addition, although the said cylindrical space 7 is partitioned off into each space R1-R6 by the partition plates 11-15 as above-mentioned, the air circulation port 8 is formed in each partition plate 11-15, and each space R1. The air of .about.R6 can be circulated through the air circulation port 8. Accordingly, it can be said that the cylindrical space 7 is not completely partitioned by the partition plates 11 to 15 but partially partitioned. The air inlet 4 is formed in the space R1, and the air outlet 5 is formed in the space R6.

  As shown in FIG. 1 and FIG. 2, in the adjacent partition plates (11 and 12, 12 and 13,...), The air circulation ports 8 are arranged alternately (alternately) with the cylinder shaft in between. . That is, the partition plates 11 to 15 having the air circulation port 8 on one side are connected in the axial direction of the cylinder 2 while changing the direction (phase) by 180 °. As a result, the air circulation ports 8 between the adjacent partition plates are arranged so as not to overlap each other when viewed in the cylinder axial direction.

  With the above configuration, as shown by the thick arrow in FIG. 2, the air introduced into the space R1 from the blower 6 through the air inlet 4 flows in the circumferential direction on both sides of the cylinder 2 in the space R1. 11 passes through the air circulation port 8 and enters the space R2. Next, it flows in the circumferential direction on both sides of the cylinder 2 in the space R2, passes through the air circulation port 8 of the partition plate 12, and enters the space R3. As described above, the air introduced from the air inlet 4 into the cylindrical space 7 flows along the flow path constituted by the cylinder 2, the sleeve 3, and the partition plates 11 to 15. It flows while changing the direction → axial direction →... And finally discharged from the space R6 through the air outlet 5.

  In the present embodiment, as described above, the partition plates 11 to 15 are configured to positively form a flow in the circumferential direction of the cylinder 2 in the cylindrical space 7. As a result, it is possible to achieve a configuration in which the cooling unevenness in the circumferential direction of the cylinder 2 hardly occurs with a compact configuration. Moreover, since the flow path of the cylindrical space 7 becomes narrow by the amount of the partition plates 11 to 15 provided, the flow velocity of the air flowing through the cylindrical space 7 increases, and the cooling efficiency of the outer peripheral surface of the cylinder 2 is good. Therefore, although it depends on the required cooling capacity, the necessity for providing auxiliary heat exchange means such as cooling fins can be reduced, and the structure can be easily manufactured at low cost.

  In the present embodiment, the annular spaces R2 to R5 sandwiched between adjacent partition plates have a shape that satisfies the following conditions. That is, for example, for the space R3, a cross-sectional area (flow path cross-sectional area) cut by a plane including the cylinder axis is S1 (see FIG. 4 as a cross-sectional view taken along the line BB in FIG. 2). Moreover, let S2 be the cross-sectional area (flow-path cross-sectional area) cut | disconnected by the plane perpendicular | vertical to a cylinder axis | shaft about the said space R3 (refer FIG. 5 as CC sectional drawing of FIG. 2). At this time, S1 <S2.

  Here, when the flow rate of air supplied from the blower 6 is Q, the axial flow velocity of the air in the space R3 is U2 = Q / S2, and the circumferential flow velocity is U1 = Q / S1. That is, since the circumferential flow velocity U1 is larger than the axial flow velocity U2 in the space R3 (U1> U2), air mainly flows in the circumferential direction in the space R3. As a result, the cylinder 2 can be uniformly cooled in the circumferential direction. In order to configure the cross-sectional area as described above, the distance L between the adjacent partition plates 12 and 13 with the space R3 interposed therebetween is related to the outer diameter of the cylinder 2 and the inner diameter of the sleeve 3. Can be determined as appropriate.

  In the above description, the relationship between the cross-sectional areas has been described by taking the case of the space R3 as an example. However, in the present embodiment, the relationship of S1 <S2 is also satisfied for the other spaces R2, R4, and R5. In particular, each of the spaces R2 to R5 is set so that the channel cross-sectional area S1 cut along the plane including the axis is less than half of the channel cross-sectional area S2 cut along the plane perpendicular to the axis (S1 <0.5 × S2). If formed, the circumferential flow velocity of air can be sufficiently increased, which is preferable.

  In addition, the air circulation ports 8 of the partition plates 11 to 15 have a ratio of the opening area (the flow passage cross-sectional area S2 of the opening area T shown in FIG. 3 cut by a plane perpendicular to the spaces R2 to R5. It is preferable that the ratio of FIG. 5) is 30% to 50%. With this configuration, the air flow in the sleeve 3 can be reliably formed in the circumferential direction, and at the same time, the cooling air can be smoothly passed from the air inlet 4 to the air outlet 5.

  Furthermore, in this embodiment, each partition plate 11-15 is provided so that the outer peripheral surface of the said cylinder 2 may be contacted. As a result, the partition plates 11 to 15 can also serve as cooling fins, and the cooling efficiency can be improved with a simple configuration.

  Moreover, in this embodiment, as shown in FIG. 3, the said partition plates 11-15 are comprised as an arc-shaped board which notched the part corresponded to the said air distribution port 8. FIG. That is, the air circulation port 8 is cut out in a circular arc shape or a fan shape to form the partition plates 11 to 15, so that the air in each of the spaces R 1 to R 5 passes through the air circulation port 8 to the downstream spaces R 2 to R 6. It can flow smoothly and the cooling efficiency is further improved.

  Further, in the present embodiment, as shown in FIGS. 1 and 2, the air circulation ports 8 of adjacent partition plates (11 and 12, 12 and 13,...) Do not overlap each other when viewed in the cylinder axial direction. Is arranged. More specifically, the air flow ports 8 of adjacent partition plates are alternately provided with the cylinder 2 (cylinder shaft) in between. Therefore, air can be reliably flowed in the circumferential direction from the air circulation port 8 to the air circulation port 8 in the spaces R2 to R5 sandwiched between the partition plates 11 to 15. As a result, the uneven cooling in the circumferential direction of the cylinder 2 is further reduced.

  The air circulation port 8 of the partition plate 11 facing the space R <b> 1 where the air inlet 4 is provided is provided at a position far from the air inlet 4. Therefore, the air introduced from the air inlet 4 surely flows in the circumferential direction even in the space R1. Similarly, the air circulation port 8 of the partition plate 11 facing the space R <b> 2 where the air outlet 5 is provided is also provided at a position far from the air outlet 5. Therefore, the air introduced into the space R6 from the air circulation port 8 flows reliably in the circumferential direction in the space R6 and is discharged from the air outlet 5.

  Although the preferred embodiment of the present invention has been described above, the present invention can be further modified as follows, for example.

  (1) The number and arrangement of the air inlets 4 and the air outlets 5 are not limited to those shown in FIG. For example, it is conceivable that an air inlet is provided at the center of the sleeve 3 in the axial direction and one air outlet is provided at both ends of the sleeve 3 in the axial direction. In this case, the partition plate may be provided between the air inlet and each air outlet.

  (2) The number of partition plates 11 to 15 is not limited to five, and may be one to four or six or more. However, if the number of partition plates is two or more and the air circulation ports are staggered, a folded air flow as shown in FIG. 2 is clearly realized, and the circumferential direction of the surface of the cylinder 2 is improved. This is preferable because uneven cooling can be reliably prevented.

  (3) The shape of the air circulation port of the partition plate is not limited to being formed as an arc shape or a fan-shaped notch as shown in FIGS. For example, it is conceivable to form a rectangular hole shape or a round hole shape air circulation port in each partition plate.

  (4) The air circulation ports 8 of the adjacent partition plates do not necessarily have to be provided so that an angular difference of 180 ° is generated. Although it is most preferable to set it as 180 degrees, even if it arrange | positions so that it may have an angle difference of 150 degrees or more and 210 degrees or less, the flow of the circumferential direction of air can be reliably formed in the inside of the sleeve 3, for example.

The perspective view which showed the whole structure of the cylinder cooling device which concerns on one Embodiment of this invention. FIG. 2 is a cross-sectional view taken along the line AA in FIG. 1. The figure which shows the structure of a partition plate. The BB cross-sectional arrow figure of FIG. CC sectional view of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cooling device 2 Cylinder 3 Sleeve 4 Air inlet 5 Air outlet 6 Blower 8 Air distribution port 11-15 Partition plate R1-R6 Space (air flow path)

Claims (10)

  A cylinder cooling device for a resin extruder, a sleeve surrounding the cylinder, an air inlet and an air outlet provided in the sleeve, a blower for supplying air from the air inlet, and a space between the cylinder and the sleeve A cylinder cooling device for a resin extruder comprising: at least one partition plate that partitions the cylinder in the cylinder axial direction; and an air circulation port that is opened in the partition plate.   The cylinder cooling device for a resin extruder according to claim 1, wherein a plurality of the partition plates are provided, and the air flow path sandwiched between adjacent partition plates is cut by a plane including the cylinder shaft. A cylinder cooling apparatus for a resin extruder, wherein S1 <S2, where S1 is an area of the flow path and S2 is a cross-sectional area of the air flow path cut by a plane perpendicular to the cylinder axis.   3. The cylinder cooling apparatus for a resin extruder according to claim 2, wherein S1 <0.5 * S2.   It is a cylinder cooling device of the resin extruder as described in any one of Claim 1- Claim 3, Comprising: As for the air circulation port of the said partition plate, the ratio of the opening area is 30% or more and 50% or less A cylinder cooling device for a resin extruder, characterized in that there is.   It is a cylinder cooling device of the resin extruder as described in any one of Claim 1- Claim 4, Comprising: The said partition plate is provided so that the outer peripheral surface of the said cylinder may be contacted. Cylinder cooling device for resin extruder.   It is a cylinder cooling device of the resin extruder as described in any one of Claim 1- Claim 4, Comprising: The said partition plate is comprised as an arc-shaped board which notched the part corresponded to the said air circulation port. A cylinder cooling device for a resin extruder, characterized in that   It is a cylinder cooling device of the resin extruder as described in any one of Claim 1- Claim 6, Comprising: While the said partition plate is provided with two or more sheets, the air circulation port of an adjacent partition plate does not mutually overlap. A cylinder cooling device for a resin extruder, which is disposed at a position.   It is a cylinder cooling device of the resin extruder as described in any one of Claim 1- Claim 6, Comprising: Air flow-flow openings of the adjacent partition plate are provided alternately on both sides of a cylinder axis | shaft. A cylinder cooling device for a resin extruder.   A cylinder cooling method for a resin extruder, wherein a sleeve is provided so as to surround the cylinder, and at least one partition plate is provided so as to partially partition the space between the cylinder and the sleeve in the cylinder axial direction. The air provided in the sleeve after supplying air into the sleeve from the air inlet provided in the sleeve and passing the air through the flow path constituted by the sleeve, the cylinder, and the partition plate. A method for cooling a cylinder of a resin extruder, wherein the cylinder is discharged from an outlet.   The cylinder cooling method for a resin extruder according to claim 9, wherein a plurality of the partition plates are provided, and the air flow path sandwiched between adjacent partition plates is cut by a plane including the cylinder shaft. A cylinder cooling method for a resin extruder, wherein S1 <S2, where S1 is an area of the flow path and S2 is a cross-sectional area of a flow path obtained by cutting the air flow path along a plane perpendicular to the cylinder axis.

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