JP2008168482A - Extruder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an extruder which hardly free from the leaking of a material by an internal pressure and can be simplified structurally. <P>SOLUTION: This extruder 2 is equipped with a main body 4 and a head principal part 6, the main body 4 comprising a screw 8, a discharge port 10, and a discharge surface 12. In addition, the head principal part 6 has a flow path 22 for the material to flow, an inlet surface 24 with an inlet of the flow path 22 and an outlet surface 26 with an outlet of the flow path 22. The flow path 22 and the discharge port 10 are connected together by the surface contact between the inlet surface 24 and the outlet surface 26. The flow path 22 is a through hole 40 formed through a monolithic member, and the spacing between the inlet surface 24 and the outlet surface 26, becomes gradually narrower from the upper side to the lower side. Further, a backup surface 44 coming into planar contact with both inlet surface 24 and outlet surface 26, becomes gradually narrower from the upper side to the lower side. In case the head principal part 6 is given a power to work from the upper side to the lower side, the surface pressure in the surface contact is boosted by the power. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an extrusion apparatus.

  An extrusion apparatus for extruding a material such as rubber or resin has a head. The head includes a flow path through which the material flows. The cross-sectional shape of the flow path gradually changes. The cross-sectional shape of the material can be changed while flowing through the flow path.

  In order to facilitate the cleaning of the flow path and the processing of the flow path, an openable head main part is employed. Japanese Laid-Open Patent Publication No. 2000-43115 discloses a head main part that can be opened and closed vertically. When the head main part is opened, the flow path is opened. This opening facilitates cleaning of the flow path.

  When the material passes through the flow path, an internal pressure acts. Due to this internal pressure, a force in the direction of opening the head acts. If the head opens even a little, the material leaks from a minute gap. In the extrusion apparatus, it is necessary to suppress leakage of the material.

Japanese Patent Application Laid-Open No. 2006-69018 discloses an extrusion apparatus provided with shell clamp means. By this shell clamp means, leakage of material can be effectively suppressed.
JP 2000-43115 A JP 2006-69018 A

  The shell clamp means is provided so as to surround the entire head. Such a shell clamp means is difficult to cope with an increase in the size of the head.

  In a vertically openable / closable head, pressing means for applying a force in the direction of closing the head can be provided at each of the left and right ends of the head. Examples of the pressing means include a wedge-shaped member and a hydraulic mechanism for inserting the wedge-shaped member. By inserting the wedge-shaped member into the gap between the external support and the head, a force in the direction of closing the head can be applied. Since this pressing means is provided only at the left and right ends, it is easy to cope with an increase in the size of the head. By this pressing means, leakage of the material due to the internal pressure can be suppressed.

  However, in this case, since the pressing means is provided only at the left and right end portions, there is a disadvantage that the force in the direction of closing the head is difficult to be transmitted to the central portion in the left and right direction of the head. A large force is required to fully close the head. The pressing means for applying a large force is increased in size. The increased pressing means causes an increase in cost. Furthermore, the time required to open and close the head is lengthened by the enlarged pressing means. When changing the size, the head is opened and closed. If the time required for opening and closing the head becomes longer, the stop time of the extrusion device also becomes longer. When the stop time becomes longer, the productivity decreases.

  An object of the present invention is to provide an extrusion apparatus in which material leakage due to internal pressure hardly occurs and the structure can be simplified.

  The extrusion apparatus of the present invention has a head main portion and a receiving surface that comes into surface contact with the head main portion. The head main part has a flow path through which a material flows, an inlet surface provided with an inlet of the flow path, and an outlet surface provided with an outlet of the flow path. The receiving surface has a discharge surface provided with a material discharge port. The flow path and the discharge port are connected by surface contact between the inlet surface and the discharge surface. The flow path includes a through hole formed through the integral member. The interval between the entrance surface and the exit surface is gradually narrowed from one side to the other side. The receiving surface is in surface contact with the inlet surface and the outlet surface. The receiving surface is gradually narrowed from one side to the other side. This extrusion device is configured such that when a force from one side to the other side is applied to the head main portion, the surface pressure of the surface contact is increased by this force.

  Preferably, the head main part includes a plurality of divided bodies. Each of these divided bodies has a partial flow path that is a part of the flow path. This partial flow path is a through hole formed through the integral member. The partial flow paths are connected to each other by surface contact between the divided bodies. This extrusion apparatus is configured such that the surface pressure of the surface contact between the divided bodies is increased by the force.

  Preferably, the interval between the inlet surface and the outlet surface is gradually narrowed from the upper side to the lower side. The receiving surface is also gradually narrowed from the upper side to the lower side. This extrusion device is configured such that when a force from the upper side to the lower side is applied to the head main part, the surface pressure of the surface contact is increased by this force.

  In this extrusion apparatus, the leakage of the material due to the internal pressure can be effectively suppressed by the integral member. This extrusion apparatus can effectively suppress material leakage with a small force.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

  FIG. 1 is a front view showing an extrusion apparatus 2 according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a sectional view in which only the head main part is extracted from FIG. FIG. 4 is a plan view of the extrusion device 2 as viewed from above. In the extrusion device 2, the material to be extruded is rubber. The extrusion apparatus 2 is an extrusion apparatus for rubber. The extrusion device 2 extrudes unvulcanized rubber. The extrusion apparatus 2 can form unvulcanized rubber into a sheet shape. The rubber formed by the extrusion device 2 can be used for, for example, a tire tread. The rubber formed by the extrusion device 2 can be used for a tire sidewall, for example.

  The extrusion device 2 includes a main body 4, a head main portion 6, and a storage portion 7. The main body 4 includes a screw 8 as a feeding mechanism, a material discharge port 10, a discharge surface 12 provided with the discharge port 10, and a main body flow path 14. The screw 8 can forcibly feed the material. The discharge surface 12 is a flat surface. A plurality of discharge ports 10 are provided on the same discharge surface 12. The feed mechanism 8 is provided inside the main body flow path 14. The accommodating portion 7 accommodates the head main portion 6. The inner surface of the housing portion 7 is in surface contact with the head main portion 6. In FIG. 4, the description of the screw 8 is omitted.

  The upper part of the accommodating part 7 is opened. The head main portion 6 is taken in and out from the upper opening 9 of the accommodating portion 7. The head main part 6 is detachable. The head main portion 6 can be easily attached and detached. The time required for replacing the head main part 6 is short. Therefore, the stop time of the extrusion apparatus 2 when the head main part 6 is replaced can be shortened. This shortening of the stop time increases the productivity of the extrusion process.

  Two discharge ports 10 are provided. There are two main body flow paths 14. There are two screws 8. One screw 8 is provided for one main body flow path 14. An extrusion apparatus having three or more main body flow paths and three or more screws may be used.

  The head main portion 6 has a flow path 22 through which rubber flows, an inlet surface 24, and an outlet surface 26. An inlet 28 of the flow path 22 is provided on the inlet surface 24. The outlet face 26 is provided with an outlet 30 of the flow path 22. The inlet surface 24 is in surface contact with the discharge surface 12. The flow path 22 and the discharge port 10 are connected by this surface contact. The flow path 22 and the main body flow path 14 are connected by this surface contact. The discharge surface 12 constitutes a part of the inner surface of the accommodating portion 7.

  Although not shown, an outlet member is attached to the outlet side of the head main portion 6. The extrusion apparatus 2 has an attachment portion 27 for attaching the outlet member. In the drawings of the present application, the outlet member is not attached. The outlet member is, for example, a preformer and / or a die plate. The outlet member also has a flow path. The final shape of the extruded rubber is determined by the outlet member. The extrusion device 2 has a pressing portion 34 for pressing the outlet member against the head main portion 6. The head main portion 6 and the outlet member are in surface contact. By this surface contact, the flow path of the outlet member and the flow path 22 are connected. The surface pressure of this surface contact is increased by the pressing part 34.

  The head main portion 6 includes a plurality of divided bodies 36. The head main portion 6 is configured by stacking a plurality of divided bodies 36. In the present embodiment, the head main portion 6 is formed by stacking four divided bodies 36. The divided body 36 has a plate shape. The divided body 36 is made of metal.

  Each of the divided bodies 36 has a partial flow path 38. This partial flow path 38 is a part of the flow path 22. The partial flow paths 38 are connected to each other by surface contact between the divided bodies 36. By the connection of the partial flow paths 38, the flow paths 22 having substantially no steps are formed. The flow path 22 which has a level | step difference in the boundary of the partial flow paths 38 may be sufficient.

  The partial flow path 38 is a through hole 40 that penetrates the integral member. In the present embodiment, the integral member is a metal plate. In the present embodiment, the divided body 36 is an integral member. Examples of the integrated member include an integrally formed metal, a part of the integrally formed metal, a welded metal, and the like. The flow path 22 is also a through hole 42 penetrating the integral member. The through hole 42 is a set of through holes 40. The flow path 22 is a set of through holes 40.

  The entire head main portion 6 may be an integral member.

  The head main portion 6 is supported by the receiving surface 44. The receiving surface 44 is a part of the inner surface of the accommodating portion 7. The head main portion 6 is in surface contact with the receiving surface 44. The receiving surface 44 has an inlet side receiving surface 46 and an outlet side receiving surface 48. The inlet surface 24 of the head main portion 6 is in surface contact with the receiving surface 46. The main body flow path 14 and the flow path 22 are connected by this surface contact. The outlet surface 26 of the head main portion 6 is in surface contact with the receiving surface 48. The receiving surface 46 is a flat surface. The receiving surface 46 is inclined with respect to the vertical direction. The receiving surface 48 is a flat surface. The receiving surface 48 extends in the vertical direction.

  The head main portion 6 is substantially supported only by the receiving surface 46 and the receiving surface 48. The other side (lower side) surface 49 of the head main portion 6 is not in contact with anything. A gap s exists on the other side (lower side) of the surface 49.

  In the present embodiment, the main body 4 has a receiving surface 46. Another member having a flow path may be interposed between the main body 4 and the head main portion 6. In this case, this separate member constitutes a receiving surface.

  As shown in FIGS. 2 and 3, the four divided bodies 36 are an inlet divided body 50, intermediate divided bodies 52 and 54, and an outlet divided body 56 in order from the discharge surface 12 side. The inlet divided body 50 is in surface contact with the receiving surface 46. The outlet divided body 56 is in surface contact with the receiving surface 48. The inlet surface 24 of the head main portion 6 is constituted by an inlet divided body 50. The outlet surface 26 of the head main portion 6 is constituted by an outlet divided body 56.

  5 and 6 show the outlet divider 56. The outlet divider 56 has an inlet surface 58 and an outlet surface 60. The exit surface 60 is the exit surface 26 of the head main portion 6. FIG. 5 is a view as seen from the entrance surface 58 side. FIG. 6 is a view as seen from the exit surface 60 side. The outlet divided body 56 has a flat plate shape as a whole. The outlet divided body 56 has two through holes 42. The upper through hole 42 is a part of the upper flow path 22. The lower through hole 42 is a part of the lower flow path 22. The cross-sectional shape of the through hole 42 is gradually changing.

  7 and 8 show changes in the cross-sectional shape of the flow path 22. FIG. 7 shows a change in the cross-sectional shape of the upper flow path 22. FIG. 8 shows a change in the cross-sectional shape of the lower flow path 22. 7A and 8B, (a) shows the shape of the through hole 42 at the inlet face of the inlet divided body 50, and (b) shows the through hole 42 at the outlet face of the inlet divided body 50 and the inlet face of the intermediate divided body 52. (C) is the shape of the through-hole 42 in the exit surface of the intermediate divided body 52 and the inlet surface of the intermediate divided body 54, and (d) is the shape of the outlet surface of the intermediate divided body 54 and the outlet divided body 56. The shape of the through hole 42 on the inlet surface is shown in FIG. The cross-sectional shape of the flow path 22 changes continuously. The inner surface of the flow path 22 is substantially smoothly continuous.

  The structure of the intermediate divided bodies 52 and 54 is the same as that of the outlet divided body 56 except for the shape of the through hole 42. The inlet divided body 50 is not constant in thickness. The entrance division body 50 has a thickness change part which becomes thin gradually from the upper part toward the lower part. The inlet surface 62 of the inlet divided body 50 is the inlet surface 24 of the head main portion 6.

  As shown in FIGS. 2 and 3, the entrance surface 24 is parallel to the vertical direction, and the exit surface 26 is inclined with respect to the vertical direction. As a result, the distance between the entrance surface 24 and the exit surface 26 gradually decreases from one side to the other side. In the present embodiment, the distance between the inlet surface 24 and the outlet surface 26 is gradually narrowed from the upper side to the lower side.

  The shape of the receiving surface 44 corresponds to the inlet surface 24 and the outlet surface 26. The receiving surface 46 is along the entrance surface 24. The receiving surface 48 is along the outlet surface 26. The receiving surface 44 is configured to gradually narrow from one side to the other side. In other words, the interval between the receiving surface 46 and the receiving surface 48 is configured to gradually narrow from one side to the other side. In the present embodiment, the receiving surface 44 is configured to gradually narrow from the upper side to the lower side. In other words, the interval between the receiving surface 46 and the receiving surface 48 is configured to gradually narrow from the upper side to the lower side.

  The extrusion device 2 has a force generation mechanism. The illustration of the force generation mechanism is omitted. The force generation mechanism is not particularly limited. Examples of the force generation mechanism include a hydraulic mechanism such as a hydraulic piston. The force generation mechanism applies a pressing force or a tensile force to the head main portion 6. The force generation mechanism pushes the upper surface 58 of the head main portion 6 downward, for example. For example, the force generation mechanism pulls the head main portion 6 downward.

  As another example of the force generation mechanism, a mechanism using a fastening member such as a bolt is exemplified. This mechanism is, for example, a bolt that spans between the head main portion 6 and the bottom portion 60 (see FIG. 2) of the accommodating portion 7. By tightening this bolt, the head main portion 6 is pulled toward the bottom 60 side. The head main portion 6 is pulled downward by this bolt.

  By such a force generation mechanism, for example, a force F1 is applied to the head main portion 6 from the upper side to the lower side. The vector of this force F1 is illustrated in FIG. The force F1 has a component S1 (not shown) in a direction perpendicular to the receiving surface 46 on the inlet side. The head main portion 6 to which the force component S1 is applied pushes the receiving surface 46 on the inlet side. Due to this reaction, the entrance surface 24 of the head main portion 6 receives a vertical drag F2 from the receiving surface 46 (see FIG. 2). The surface pressure of the surface contact is increased between the receiving surface 46 (discharge surface 12) and the inlet surface 24 by the force component S1 and the normal force F2. Thereby, the leakage of rubber at the boundary between the receiving surface 46 (discharge surface 12) and the inlet surface 24 is suppressed.

  In addition, it is preferable that the force generation mechanism can apply a force F3 having a component from the other side (lower side) to the one side (upper side) to the head main portion 6 (see FIG. 2). With this force F3, the head main portion 6 can be easily removed.

  In FIG. 3, what is indicated by reference numeral k <b> 1 is a contact surface between the divided bodies 36. The normal force F2 has a component S2 (not shown) perpendicular to the contact surface k1. By this force component S2, the surface pressure of the surface contact at the contact surface k1 is increased. Thereby, the leak of the rubber | gum in the contact surface k1 is suppressed.

  As described above, in the present embodiment, the receiving surface 48 on the outlet side is the inner surface of the accommodating portion 7. As another form, the outlet-side receiving surface 48 may be formed by the outlet member. In this case, the normal force F <b> 2 increases the surface pressure of the surface contact between the outlet member and the outlet surface 26. The receiving surface 48 may not be the inner surface of the accommodating portion 7. Another member having a flow path may be interposed between the inner surface of the accommodating portion 7 and the outlet surface 26.

  High pressure is required to extrude the rubber. In the rubber extrusion device, a large internal pressure acts on the flow path. This internal pressure tends to cause rubber leakage from the boundary surface. The present invention effectively increases the surface pressure at the boundary surface and effectively suppresses leakage.

  In the above-described conventional open / close head, the internal pressure acting on the flow path tends to act in the direction of opening the head. In order to counter this internal pressure, the conventional open / close head requires a great amount of force to close the head. In order to supply this great force, a large facility such as a large clamp or a large hydraulic facility is required. This large facility increases the manufacturing cost of the extrusion device. Furthermore, this large facility takes time to operate. Furthermore, when the conventional open / close head is enlarged, it is difficult to spread the force for closing the head over the entire head. The conventional open / close head is likely to have a leakage problem especially when it is enlarged.

  The force due to the internal pressure is divided into a component S3 in the flow direction of the material (rubber) and a component S4 orthogonal to the flow direction. The force component S3 is a driving force for flowing rubber. On the other hand, the force component S4 acts in a direction in which the flow path 22 is expanded. In the conventional open / close head described above, the force component S4 tends to act in the direction of opening the head.

  In the extrusion apparatus 2, the flow path 22 is a through hole 42 that penetrates the integral member. This integral member efficiently receives the force component S4 acting on the flow path 22.

  As described above, the head main portion 6 is divided into a plurality of divided bodies 36. The extending direction of the contact surface k <b> 1 between the divided bodies 36 has an angle with respect to the flow direction of the flow path 22. Therefore, the force component S4 is less likely to act in the direction of separating the divided bodies 36 from each other.

  In FIG. 3, what is indicated by the symbol θ1 is an angle formed by the direction V1 orthogonal to the inner surface of the flow path 22 and the contact surface k1. From the viewpoint of suppressing rubber leakage from the contact surface k1, the angle θ1 is preferably 70 degrees or less, more preferably 60 degrees or less, more preferably 50 degrees or less, and particularly preferably 40 degrees or less. The direction V1 and the contact surface k1 may be parallel. The angle θ1 can be determined at each point on the inner surface of the flow path 22.

  As described above, the distance between the inlet surface 24 and the outlet surface 26 gradually decreases from one side toward the other side. Correspondingly, the receiving surface 44 is also gradually narrowed from one side to the other side. The direction of gradually narrowing is not limited. In the above embodiment, the distance between the inlet surface 24 and the outlet surface 26 gradually decreases from the upper side to the lower side. In this case, the head main portion 6 can be taken in and out from above, and the replacement of the head main portion 6 becomes extremely easy. Further, in this case, gravity acting on the head main portion 6 can act in the same manner as the force F1. Due to the gravity acting on the head main part 6, rubber leakage can be effectively prevented.

  In FIG. 3, a double arrow θ <b> 2 indicates an angle formed by the entrance surface 24 and the exit surface 26. From the viewpoint of facilitating removal of the head main part, the angle θ is preferably 3 degrees or more, more preferably 5 degrees or more, more preferably 7 degrees or more, and particularly preferably 8.5 degrees or more. From the viewpoint of increasing the surface pressure of surface contact with less force and efficiently suppressing material leakage, the angle θ is preferably 30 degrees or less, more preferably 20 degrees or less, more preferably 15 degrees or less, and more preferably 10 degrees or less. Is particularly preferred.

  In FIG. 3, what is indicated by a double-headed arrow θ3 is an inclination angle of the entrance surface 24 with respect to the vertical direction. From the viewpoint of facilitating removal of the head main part, the angle θ3 is preferably 3 degrees or more, more preferably 5 degrees or more, more preferably 7 degrees or more, and particularly preferably 8.5 degrees or more. From the viewpoint of increasing the surface pressure of the surface contact with less force and efficiently suppressing the leakage of the material, the angle θ3 is preferably 30 degrees or less, more preferably 20 degrees or less, more preferably 15 degrees or less, and more preferably 10 degrees or less. Is particularly preferred.

  The head main portion 6 may not be divided or may be divided. The number of divisions of the head main portion 6 is not particularly limited. The smaller the number of divisions of the head main part 6, the less the possibility of material leakage from the contact surface k1. On the other hand, the larger the number of divisions of the head main portion 6, the more the weight of the divided body 36 decreases. This reduction in weight can facilitate the handling of the head main portion 6. Further, the thickness of the divided body 36 can be reduced as the number of divisions of the head main portion 6 is increased. The smaller the thickness of the divided body 36, the easier the processing of the partial flow path 38 is. If the thickness of the divided body 36 is reduced, the partial flow path 38 can be easily milled by a machine. The number of divisions of the head main portion 6 can be determined by comprehensively considering the size of the head main portion 6, the characteristics of the material to be flowed, the internal pressure, the ease of processing of the partial flow path 38, and the like.

  The present invention can be applied to any extrusion apparatus.

FIG. 1 is a front view of an extrusion apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line II-II in FIG. FIG. 3 is a diagram in which only the main part of the head is extracted from FIG. FIG. 4 is a view of the extrusion apparatus of FIG. 1 as viewed from above. FIG. 5 is a view of the divided body as viewed from the inlet side. FIG. 6 is a view of the divided body as viewed from the outlet side. FIG. 7 is a diagram showing a cross-sectional shape of the flow path. FIG. 8 is a diagram showing a cross-sectional shape of the flow path.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 ... Extrusion apparatus 4 ... Main body 6 ... Head main part 8 ... Screw 10 ... Discharge port 12 ... Discharge surface 14 ... Main body flow path 22 ... Flow path 24. ..Inlet surface 26 of head main part 26. Outlet surface of head main part 36. Split body 38. Partial flow path 40 ... Through hole 42 ... Through hole 44 ... Receiving surface 46・ ・ ・ Inlet side receiving surface 48 ・ ・ ・ Outlet side receiving surface 50 ・ ・ ・ Inlet divided body 52 ・ ・ ・ Intermediate divided body 54 ・ ・ ・ Intermediate divided body 56 ・ ・ ・ Exit divided body

Claims (3)

A head main portion and a receiving surface in surface contact with the head main portion;
The head main part has a flow path through which a material flows, an inlet surface provided with an inlet of the flow path, and an outlet surface provided with an outlet of the flow path,
The receiving surface has a discharge surface provided with a material discharge port,
By the surface contact between the inlet surface and the discharge surface, the flow path and the discharge port are connected,
The flow path includes a through hole formed through the integral member,
The interval between the entrance surface and the exit surface is gradually narrowed from one side to the other side,
The receiving surface is in surface contact with the inlet surface and the outlet surface, and is gradually narrowed from one side to the other side,
The extrusion apparatus according to claim 1, wherein when a force from one side to the other side is applied to the head main portion, the surface pressure of the surface contact is increased by the force. The head main part is composed of a plurality of divided bodies,
Each of these divided bodies has a partial flow path that is part of the flow path,
This partial flow path is a through hole formed through the integral member,
The partial flow paths are connected to each other by surface contact between the divided bodies,
The extrusion device according to claim 1, wherein the surface pressure of the surface contact between the divided bodies is increased by the force. The interval between the entrance surface and the exit surface is gradually narrowed from the upper side to the lower side,
The receiving surface is also gradually narrowed from the upper side to the lower side,
The extrusion apparatus according to claim 1, wherein when a force from the upper side to the lower side is applied to the head main portion, the surface pressure of the surface contact is increased by the force.

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