JP7202952B2 - Die equipment and fixtures - Google Patents

Description

The present invention relates to die apparatus and fixtures.

An inflation molding apparatus is known that extrudes a molten resin from a die into a tubular shape, blows air into the tube to expand it, and forms a thin film. There are two types of inflation molding apparatuses: an upward type that extrudes molten resin upward and a downward type that extrudes molten resin downward. As in Patent Document 1, when the molten resin is water-cooled, a downward type is mainly used.

JP-A-2005-231266

In a downward-facing inflation molding device, the lip of the die faces downward, making maintenance such as cleaning difficult. For this reason, a hanger such as a chain is fixed to the die, the die is lifted by the hanger, turned over, and maintenance is performed after the discharge port faces upward.

By the way, recently, the development of a die lip drive mechanism for controlling the thickness of the film by adjusting the lip width, which is fixed around the lip of the die, is underway. Since the die lip drive mechanism protrudes in the radial direction of the die, simply fixing the sling to the die interferes with the sling and the die lip drive mechanism, making it impossible to reverse the die.

The present invention has been made in view of such circumstances, and one of the exemplary objects of certain aspects thereof is a technology capable of reversing the die of a downward-facing inflation molding apparatus to which a die lip drive mechanism is fixed. is to provide

In order to solve the above problems, a die device according to one aspect of the present invention is a die device for inflation molding, comprising a die for extruding resin into a tubular shape, and a lip width fixed around the lip of the die for adjusting the width of the lip. a die lip drive mechanism for performing the above-mentioned process; and a shaft portion fixed to the die and protruding from the die lip drive mechanism in the radial direction of the die.

Another aspect of the invention is a fixture. This jig is a jig used for maintenance of a die to which a die lip drive mechanism for adjusting the lip width is fixed. Prepare.

Arbitrary combinations of the above constituent elements, and mutual substitution of the constituent elements and expressions of the present invention in methods, devices, systems, etc. are also effective as aspects of the present invention.

ADVANTAGE OF THE INVENTION According to this invention, the die|dye of the downward type inflation molding apparatus with which the die lip drive mechanism was fixed can be reversed.

It is a figure which shows schematic structure of an inflation molding apparatus. 2 is a cross-sectional view showing the die of FIG. 1 and its surroundings; FIG. 2 is a bottom view showing the die of FIG. 1 and its surroundings; FIG. It is a perspective view which shows the upper part of the outer peripheral member of FIG. 2, and the die lip drive mechanism attached to it. It is a side view which shows the upper part of the outer peripheral member of FIG. 2, and the die lip drive mechanism attached to it. FIG. 3 is a perspective view showing the die lip driving mechanism of FIG. 2; FIG. 3 is a perspective view showing the die lip driving mechanism of FIG. 2; 8A and 8B are explanatory diagrams for explaining the operation of the die lip drive mechanism. 2 is a perspective view showing a die device 2 of FIG. 1; FIG. FIG. 2 is a plan view showing the die device 2 of FIG. 1; FIG. 10 is a perspective view of the jig of FIG. 9; It is a schematic block diagram which shows a die|dye reversing apparatus. It is a perspective view of a die device according to a modification of the first embodiment. It is a top view which shows the die|dye apparatus which concerns on 2nd Embodiment. It is a cross-sectional view showing a die device according to a second embodiment. It is a top view which shows the die|dye apparatus which concerns on 3rd Embodiment. It is a sectional view showing a die device concerning a 3rd embodiment. It is a sectional view showing die device 2 concerning a 4th embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and overlapping descriptions are omitted as appropriate.

FIG. 1 is a diagram showing a schematic configuration of an inflation molding apparatus 1 according to the first embodiment. The inflation molding device 1 comprises a die device 2 , a first cooling device 4 , a second cooling device 5 , a first pair of stabilizers 6 , pinch rolls 7 and a control device 8 . The inflation molding device 1 is a so-called downward-type inflation molding device in which a resin is extruded downward from a die device 2 .

Molten resin is supplied to the die device 2 from an extruder (not shown). The supplied molten resin is extruded from a ring-shaped discharge port 18 a formed in the die device 2 . At that time, air is jetted into the inside of the extruded resin from an air jet port (not shown) formed inside the discharge port 18a, and a thin resin film (hereinafter, also referred to as a “bubble”) swells into a tubular shape. ) is molded.

The first cooling device 4 is arranged below the die device 2 . The first cooling device 4 cools the bubbles by blowing cooling air onto the bubbles.

The second cooling device 5 is arranged below the first cooling device 4 . The second cooling device 5 cools the bubbles by bringing cooling water into direct contact with the bubbles.

A pair of stabilizers 6 are arranged below the second cooling device 5 and guide the bubble between a pair of pinch rolls 7 . A pair of pinch rolls 7 are arranged below the stabilizer 6 . A pair of pinch rolls 7 pull down the guided bubble and flatten it. The folded film is wound up by a winder (not shown).

The control device 8 is a device for integrally controlling the inflation molding device 1 . For example, the control device 8 controls the die device 2 to adjust the bubble thickness.

2 and 3 are a cross-sectional view and a bottom view, respectively, showing the die and its surroundings. The die device 2 includes a die 9 and multiple die lip drive mechanisms 16 . Die 9 includes a die body 10 and a lip portion 11 . The die body 10 is a substantially cylindrical member. The die body 10 is formed with a channel 10a through which molten resin flows. Lip portion 11 includes an inner peripheral member 12 and an outer peripheral member 14 . The inner peripheral member 12 is a substantially cylindrical member having a smaller diameter than the die body 10 and is arranged below the die body 10 . The outer peripheral member 14 is an annular member and surrounds the inner peripheral member 12 . Between the inner peripheral member 12 and the outer peripheral member 14, a ring-shaped slit 18 extending in the vertical direction is formed. The channel 10a of the die body 10 and the slit 18 are in communication. The molten resin flows downward through the flow path 10a and the slit 18, and the molten resin is extruded from the outlet (that is, the lower end opening) 18a of the slit 18, forming a bubble having a thickness corresponding to the width of the outlet 18a. .

A plurality of heaters 19 are attached to the outer periphery of the die body 10 . A heater 19 is also attached to the outer periphery of the outer peripheral member 14 . The die body 10 and the peripheral member 14 are heated to a required temperature by the heater 19 . As a result, the molten resin flowing inside the die 9 can be maintained at an appropriate temperature and in a molten state.

The plurality of die lip drive mechanisms 16 are arranged in the circumferential direction without any gap so as to surround the upper end side of the outer peripheral member 14 . The die lip drive mechanism 16 is particularly attached to the peripheral member 14 in a cantilever fashion. Each of the plurality of die lip driving mechanisms 16 can apply a radially inward pressing load or a radially outward tensile load to the outer peripheral member 14 . Therefore, by adjusting the plurality of die lip driving mechanisms 16, the width of the discharge port 18a (that is, the lip width) can be partially adjusted in the circumferential direction, and the thickness of the bubble can be partially controlled in the circumferential direction. When the thickness of the bubble varies, for example, a tensile load is applied to the outer peripheral member 14 from the die lip drive mechanism 16 corresponding to the thin portion (for example, located above the thin portion). Increase the width of the lip corresponding to (i.e., upper) the portion of reduced thickness. This reduces variations in the bubble thickness.

4 and 5 are a perspective view and a side view showing the upper portion of the peripheral member 14 and the die lip drive mechanism 16 attached thereto. 4 and 5, only one die lip drive mechanism 16 is shown, and the remaining die lip drive mechanisms 16 are omitted. 6 and 7 are perspective views showing the die lip driving mechanism 16. FIG. FIG. 7 shows a state in which one of the pair of support members 30 is removed.

The upper portion of the outer peripheral member 14 has a small-diameter portion 25 formed at the upper end, a medium-diameter portion 26 formed below the small-diameter portion 25 and having a larger diameter than the small-diameter portion 25, and a medium-diameter portion 26 below the medium-diameter portion 26. and a large diameter portion 27 formed to have a larger diameter than 26 . The small diameter portion 25 has a flexible lip portion 22 . The flexible lip portion 22 refers to the portion of the small diameter portion 25 above the recessed notch portion 20 provided along the circumferential direction. The flexible lip portion 22 is elastically deformed with the notch portion 20 as a boundary. The flexible lip portion 22 includes a cylindrical body portion 28 and an annular projecting surrounding portion 29 projecting radially outward from the body portion 28 .

The die lip driving mechanism 16 includes a pair of support members 30 attached to the outer peripheral member 14, a rotating shaft 32 fixed to the pair of supporting members 30, and a lever 34 supported rotatably about the rotating shaft 32. , an operating rod 36 that receives the rotational force of the lever 34 and operates in the axial direction; a connecting member 38 that axially connects the operating rod 36 and the flexible lip portion 22; and the operating rod is slidable in the axial direction. It includes a supporting bearing member 40 and an actuator 24 that imparts a rotational force to the lever 34 .

A pair of support members 30 are formed in a flat plate shape and screwed to the outer peripheral member 14 so as to be parallel to each other. A space for interposing a lever 34 is provided between the pair of support members 30 . The bearing member 40 is formed in a rectangular parallelepiped shape and screwed to the outer peripheral member 14 radially inside the support member 30 . An insertion hole 42 is formed through the bearing member 40 in the radial direction. The inner peripheral surface of the insertion hole 42 constitutes a so-called slide bearing (non-lubricating type bearing) and supports the operating rod 36 in a slidable manner.

The rotating shaft 32 is fixed to the pair of supporting members 30 so that the shaft is oriented horizontally and substantially perpendicular to the radial direction.

The operating rod 36 is formed in a stepped columnar shape, and its intermediate portion is inserted through the insertion hole 42 of the bearing member 40 . A reduced diameter portion 44 is provided on the axially outer side of the operating rod 36 . The reduced diameter portion 44 functions as a connecting portion with the lever 34 as described later. A concave engaging portion 46 is provided axially inside the operating rod 36 . The engaging portion 46 functions as a connecting portion with the connecting member 38 as described later. The outer peripheral surface of the protruding encircling portion 29 of the flexible lip portion 22 (hereinafter referred to as the “pressure receiving surface 23 ”) faces the tip end surface of the operating rod 36 .

The connecting member 38 is formed in a bifurcated shape when viewed in longitudinal section. Specifically, engaging portions 48 and 50 protruding downward are provided on a surface of the connecting member 38 that faces the outer peripheral member 14 in the axial direction. Engagement portion 48 is generally complementary in shape to engagement portion 46 of actuation rod 36 . An annular engaging groove 52 recessed downward in the axial direction is formed in the protruding surrounding portion 29 of the flexible lip portion 22 . The engaging portion 50 has a substantially complementary shape with the engaging groove 52 .

The operating rod 36 and the connecting member 38 are screwed so that the engaging portion 48 engages with the engaging portion 46 and the engaging portion 50 engages with the engaging groove 52 . Mutual facing surfaces of the engaging portion 48 and the engaging portion 46 are tapered surfaces. As a result, the distal end surface of the operating rod 36 is pressed against the pressure receiving surface 23 of the flexible lip portion 22 as the screw 54 is tightened, and the operating rod 36 and the flexible lip portion 22 are firmly fixed. A portion of the flexible lip portion 22 is sandwiched between the engaging portion 50 of the connecting member 38 and the distal end portion of the operating rod 36 . As a result, the operating rod 36 is axially connected to the flexible lip portion 22 .

The lever 34 has an elongated plate-like main body 60 extending in the radial direction, one end of which is rotatably supported by the rotating shaft 32 . The lever 34 is mounted so that the body 60 and the actuating rod 36 are substantially parallel in the non-actuated state. A bifurcated connecting portion 62 is provided so as to extend from one end of the main body 60 in a direction perpendicular to the axis of the main body 60 . That is, the connecting portion 62 is composed of a pair of connecting pieces 64, the distance between which is slightly larger than the outer diameter of the diameter-reduced portion 44 of the operating rod 36, and the width thereof is slightly smaller than the length of the diameter-reduced portion 44. there is With such a configuration, the lever 34 and the operating rod 36 are connected in such a manner that the connecting portion 62 fits into the reduced diameter portion 44 .

In addition, as long as the configuration is such that the rotational force of the lever 34 is directly applied to the operating rod 36, the configuration is not limited to this embodiment. For example, the connecting portion 62 may be configured so as not to extend in the direction perpendicular to the axis of the main body 60 . The axis of the main body 60 and the extending direction of the connecting portion 62 may form an acute angle or may form an obtuse angle. Also, the main body 60 and the actuating rod 36 may not be parallel when the lever 34 is in the non-actuated state.

The actuator 24 is pneumatically driven in this embodiment, and includes two sets of bellows 70, 72 and bellows 71, 73 operated by supplying and discharging compressed air, a first base 75, and a shaft of the first base 75. It includes a second base 76 arranged downward and four connecting rods 77 . The first base 75 and the second base 76 are spaced apart in the axial direction and connected by four connecting rods 77 . Bellows 70, 72 are arranged between the lever 34 and the first base 75, and bellows 71, 73 are arranged between the lever 34 and the second base. That is, the end portion of the lever 34 that becomes the power point is supported so as to be sandwiched between the bellows 70 and 72 and the bellows 71 and 73 . By supplying compressed air to one of the bellows 70, 72 or the bellows 71, 73, the lever 34 is rotated clockwise or counterclockwise in the figure.

In FIG. 5, when the bellows 70 and 72 are expanded by applying pressure to the bellows 70 and 72 by supplying compressed air, the lever 34 rotates counterclockwise in the figure, and the rotational force is applied to the left side of the operating rod 36 in the axial direction. (ie radially outward). As a result, a tensile load is applied to the flexible lip portion 22, and the gap at the portion of the discharge port 18a of the corresponding (that is, radially inner side of the die lip drive mechanism 16) portion of the slit 18 changes in the direction of increasing. On the other hand, when compressed air is supplied to apply pressure to the bellows 71 and 73 and the bellows 71 and 73 are extended, the lever 34 rotates clockwise in the drawing, and the rotational force is applied to the right side of the operating rod 36 in the axial direction (that is, the radial direction). direction inward). As a result, a pressing load is applied to the flexible lip portion 22, and the gap at the corresponding slit 18 portion changes in the direction of decreasing.

In order to realize such pneumatic driving, compressed air is supplied from a pressure adjusting device (not shown) through a supply path 75a formed in the first base 75 and a supply path 76a supplied to the second base 76. be. The pressure regulating device controls the pressure inside the bellows 70-73 based on control commands from the control device 8. FIG.

FIG. 8 is an explanatory diagram for explaining the operation of the die lip driving mechanism 16. FIG. FIG. 8(A) shows the neutral state of the die lip drive mechanism 16 (the bellows 70 to 73 are both non-operating), and FIG. activated state).

According to the die lip drive mechanism 16, the rotational force of the lever 34 is applied directly to the operating rod 36 at the point P of action. That is, the rotational force of the lever 34 is applied to the flexible lip portion 22 as an axial force of the operating rod 36 . At this time, since the operating rod 36 is stably supported by the outer peripheral member 14 , the force in the axial direction is efficiently transmitted to the flexible lip portion 22 . As a result, it is possible to efficiently apply the driving force for adjusting the gap between the inner peripheral member 12 and the outer peripheral member 14 .

In the present embodiment, as shown in FIG. 8A, a straight line connecting a connection point between the lever 34 and the operating rod 36 (the point of action P of the lever 34) and the rotation shaft 32 (the fulcrum of the lever 34) L1 is configured to be orthogonal to the axis L2 of the actuation rod 36. As shown in FIG. As a result, the tangential direction of the virtual circle C passing through the action point P about the rotation shaft 32 and the axial direction of the operating rod 36 coincide.

Therefore, as shown in FIG. 8B, the direction at the point P of action of the rotational force of the lever 34 coincides with the axial direction of the operating rod 36 . As a result, the rotational force of the lever 34 becomes the driving force in the axial direction of the actuating rod 36 as it is, so that the force transmission efficiency can be maximized. That is, it is possible to apply the driving force of the actuator 24 very efficiently when expanding the flexible lip portion 22 (see the thick line arrow in the figure).

Although illustration is omitted, even when the die lip driving mechanism 16 is in the narrow operating state (the state in which only the bellows 71 and 73 are operated), the direction of the force in FIG. The direction at the point of action P coincides with the axial direction of the operating rod 36 . As a result, the rotational force of the lever 34 becomes the driving force in the axial direction of the operating rod 36 as it is during the expansion operation, and the force transmission efficiency can be maximized. That is, according to the die lip driving mechanism 16, it is possible to efficiently apply a driving force for adjusting the distance between the ejection openings 18a of the slit 18. FIG.

In addition, as long as the configuration is such that the rotational force of the lever 34 is directly applied to the operating rod 36, the configuration is not limited to this embodiment. For example, the extending direction of the connecting portion 62 (the direction connecting the rotating shaft 32 and the point of action P) forms an acute or obtuse angle with the axial direction of the operating rod 36, and as a result, the direction of the rotational force of the lever 34 at the point of action P (for convenience, also referred to as "rotational force acting direction") and the axial direction of the operating rod 36 (for convenience, also referred to as "axial force acting direction") may be configured so as not to coincide. In that case, the main body 60 and the operating rod 36 may be parallel, while the axis of the main body 60 and the extending direction of the connecting portion 62 may form an acute or obtuse angle. Alternatively, the axis of the main body 60 and the extending direction of the connecting portion 62 may be perpendicular, but the main body 60 and the operating rod 36 may not be parallel. Alternatively, the axis of the main body 60 and the extending direction of the connecting portion 62 may form an acute or obtuse angle, and the main body 60 and the operating rod 36 may not be parallel. Further, the main body 60 may have at least a bent portion or a curved portion (a configuration in which the axis cannot necessarily be specified).

The above is the basic configuration of the inflation molding apparatus 1 . Next, the die device 2 will be described in more detail.

9 and 10 are a perspective view and a plan view showing the die device 2. FIG. In FIG. 9, the die lip drive mechanism 16 and the heater 19 are omitted. The die device 2 further includes a jig 110 for die maintenance. FIG. 11 is a perspective view of the jig 110. FIG.

The jig 110 includes a first shaft portion 121 , a second shaft portion 122 , and a fixing portion 130 for fixing the first shaft portion 121 and the second shaft portion 122 to the die 9 .

The fixing portion 130 includes a first fixing portion 131 fixed to the outer peripheral surface 9a of the die 9, and a surface 9b (hereinafter also referred to as “bottom surface 9b”) opposite to the surface of the die 9 on which the discharge port 18a is formed. and at least one (six in the illustrated example) second fixing portions 132 fixed to the . In this embodiment, the first fixing portion 131 is formed in a cylindrical shape having an inner diameter that is substantially the same as the outer diameter of the die body 10 .

The second fixing portion 132 has an inverted L shape. Specifically, the second fixing portion 132 has one end fixed to the first fixing portion 131 , an axially extending portion 134 extending parallel to the central axis of the first fixing portion 131 , and a radially extending portion 134 extending radially from the axially extending portion 134 . and an inwardly extending radial extension 136 .

The first fixing part 131 is fixed to the outer peripheral surface 9a of the die 9 with screws, and at least one second fixing part 132 is fixed to the bottom surface 9b of the die 9 with screws. When the radially extending portion 136 is placed on the bottom surface of the die 9, the screw hole (not shown) formed in the outer peripheral surface of the die 9 and the insertion hole 131a formed in the first fixing portion 131 They are formed so that their height positions (positions in the axial direction of the die 9) match. Therefore, the jig is placed on the die 9 so that the radially extending portion 136 is placed on the bottom surface 9b of the die 9, and the screw holes formed in the outer peripheral surface 9a of the die 9 and the first fixing portion 131 are formed. The die 9 and the jig 110 can be easily aligned by rotating the jig 110 around the central axis A of the die 9 so that the corresponding insertion holes 131a face each other.

The first shaft portion 121 and the second shaft portion 122 are rod-shaped members. The cross section perpendicular to the longitudinal direction of first shaft portion 121 and second shaft portion 122 is circular in the present embodiment, but is not limited to this, and may be rectangular or other shape. The first shaft portion 121 and the second shaft portion 122 are coaxially fixed to the first fixing portion 131 . Therefore, by fixing the fixed part 130 to the die 9 , the first shaft part 121 and the second shaft part 122 are coaxially fixed to the die 9 .

The first shaft portion 121 and the second shaft portion 122 preferably extend along the central axis of the first shaft portion 121 and the second shaft portion 122 in plan view in a state where the fixing portion 130 is fixed to the die 9. It is fixed to the first fixing portion 131 so as to pass through the central axis A of the die 9 or its vicinity, that is, so as to extend in the radial direction of the die 9 . In other words, the first shaft portion 121 and the second shaft portion 122 are preferably located at the central axis of the first shaft portion 121 and the second shaft portion 122 in plan view in a state where the fixing portion 130 is fixed to the die 9. It is fixed to the first fixing portion 131 so that the extension line passes through the center of the annular first fixing portion 131 or its vicinity.

More preferably, the first shaft portion 121 and the second shaft portion 122 are arranged such that, when the fixing portion 130 is fixed to the die 9 , extension lines of their central axes are aligned with the center of gravity of the die 9 and between the die 9 and the die 9 . It is attached to the first fixing part 131 so as to pass through the center of gravity of the fixed fixing part 130 and the vicinity thereof when the object is regarded as one object.

The first shaft portion 121 and the second shaft portion 122 protrude outward from the die lip driving mechanism 16 in the radial direction of the die 9 when the jig 110 is fixed to the die 9 . Specifically, the first shaft portion 121 and the second shaft portion 122 protrude radially outward from the circumscribed circle of the plurality of die lip drive mechanisms 16 (the circle indicated by the dashed line in FIG. 10) in plan view. Hereinafter, the portion of the first shaft portion 121 that protrudes outward from the die lip drive mechanism 16 in the radial direction of the die 9 is referred to as a first protrusion portion 121a, and the portion of the second shaft portion 122 that protrudes outward from the die lip drive mechanism 16 is referred to as a first protrusion portion 121a. The portion is called a second projecting portion 122a.

FIG. 12 is a schematic configuration diagram showing the die reversing device 100. As shown in FIG. The die reversing device 100 includes a first support 111 and a second support 112 and a rotation drive device 114 .

A first support 111 and a second support 112 point to the die apparatus 2 . Specifically, the first strut 111 rotatably supports the first shaft portion 121 , and the second strut 112 rotatably supports the second shaft portion 122 . That is, the first support 111 and the second support 112 support the die 9 via the jig 110 . More specifically, the first support 111 supports the first protrusion 121a of the first shaft 121, and the second support 112 supports the second protrusion 122a of the second shaft 122 (see FIG. 12). .

The rotation drive device 114 includes, for example, a motor, and rotates the first shaft portion 121 by 1/2 based on the user's instruction. By rotating the jig 110 and thus the die device 2, the die 9 can be turned upside down so that the surface 9e of the die 9 on which the discharge port 18a is formed faces upward. At this time, since the first projecting portion 121a and the second projecting portion 122a projecting radially outward from the die lip driving mechanism 16 are supported, the components of the die reversing device 100 and the like are prevented from interfering with the die lip driving mechanism 16. can be avoided.

Next, the flow during maintenance of the die 9 will be described. The user removes the heater 19 from the die 9, attaches the jig 110 to the die 9 supported by the pedestal, suspends the jig 110 together with the die 9 with a crane or the like, and moves the jig 110 as shown in FIG. As a result, the die 9 is supported by the pillars 111 and 112 . Subsequently, the user drives the rotation drive device 114 to rotate the first shaft portion 121 by 1/2, and reverses the jig 110 and thus the die 9 . Then, the user cleans the die 9 by scraping off the resin adhering to the surface of the die 9 on which the discharge port 18a is formed, with a tool such as a spatula or a scraper.

According to the present embodiment described above, since the jig 110 includes the shaft portions 121 and 122 that protrude radially outward from the die lip drive mechanism 16 , the component parts of the die reversing device 100 and the like are attached to the die lip drive mechanism 16 . It is possible to reverse the die 9 without interfering with the .

Further, according to the present embodiment, the jig 110 is fixed to the outer peripheral surface 9a and the bottom surface 9b of the die 9, so that it is stronger than the case where it is fixed only to the outer peripheral surface 9a or only to the bottom surface 9b. The jig 110 can be fixed to the die 9 at the same time, improving safety.

One aspect of the present invention has been described above based on the first embodiment. Next, a modification related to the first embodiment will be described.

First Modified Example of First Embodiment In the embodiment, the case where the fixing portion 130 includes the first fixing portion 131 and the second fixing portion 132 has been described, but the fixing portion 130 is not limited to this. , it may include only the first fixing portion 131 fixed to the outer peripheral surface 9a, that is, may not include the second fixing portion 132 fixed to the bottom surface 9b.

Second Modification of First Embodiment FIG. 13 is a perspective view showing a die device 2 according to a modification of the first embodiment. FIG. 13 corresponds to FIG. In this modified example, the plurality of second fixing portions 132 are integrated. Specifically, the radially extending portions 136 of the plurality of second fixing portions 132 extend to the center and are integrated. According to this modification, the same effects as those of the embodiment can be obtained.

(Second embodiment)
14 and 15 are a plan view and a cross-sectional view, respectively, showing a die device 2 according to a second embodiment. FIG. 15 is a cross-sectional view taken along a plane including the central axis A of the die 9. As shown in FIG. 14 and 15, the display of the heater 19 is omitted. The description will focus on the differences from the first embodiment.

The fixed portion 130 includes a first block 141 provided at one end of the first shaft portion 121 and a second block 142 provided at one end of the second shaft portion 122 . The cross sections of the first block 141 and the second block 142 perpendicular to the longitudinal direction of the shafts 121 and 122 are rectangular in this embodiment, but are not limited to this, and may be other polygonal or other shapes. There may be.

A first recessed portion 9c and a second recessed portion 9d corresponding to the first block 141 and the second block 142, respectively, are formed on the outer peripheral surface 9a of the die 9. As shown in FIG. The first block 141 is inserted into the first recess 9c and fastened to the bottom surface of the first recess 9c (the surface facing the first block in the longitudinal direction of the first shaft portion 121) 9ca with a screw. The bottom surface 9ca of the first recess 9c and the opposing surface 141a of the first block 141 that contacts the bottom surface 9ca are preferably flat. Similarly, the second block 142 is inserted into the second recess 9d and fastened to the bottom surface (the surface facing the second block in the longitudinal direction of the second shaft portion 122) 9da of the second recess 9d with screws. The bottom surface 9da of the second recess 9d and the opposing surface 142a of the second block 142 that contacts the bottom surface 9da are preferably flat.

According to the present embodiment described above, since the jig 110 includes the shaft portions 121 and 122 that protrude radially outward from the die lip drive mechanism 16 , the component parts of the die reversing device 100 and the like are attached to the die lip drive mechanism 16 . It is possible to reverse the die 9 without interfering with the .

Further, according to the present embodiment, since the jig 110 is relatively compact, specifically, the first shaft portion 121 and the second shaft portion 122 are separate bodies and can be stacked on top of each other for storage. The space of the place is narrow and suffices.

Further, according to the present embodiment, since the bottom surfaces 9ca and 9da of the recesses 9c and 9d and the opposed surfaces 141a and 142a of the blocks 141 and 142 that contact the bottom surfaces 9ca and 9da are preferably flat, they can be fixed by screws. Both can be fixed relatively firmly.

One aspect of the present invention has been described above based on the second embodiment.

(Third Embodiment)
16 and 17 are a plan view and a cross-sectional view showing a die device 2 according to the third embodiment. FIG. 17 is a cross-sectional view taken along a plane including the central axis A of the die 9. As shown in FIG. The description will focus on the differences from the first embodiment.

The fixed part 130 is formed in an annular shape and fixed to the bottom surface 9 b of the die 9 so that the center thereof coincides with the central axis A of the die 9 , for example. Since the fixing portion 130 is annular, various members (not shown) can be attached to the bottom surface 9b of the die 9. As shown in FIG. The first shaft portion 121 and the second shaft portion 122 are coaxially fixed to the fixed portion 130 .

According to this embodiment, the same effects as those of the first embodiment can be obtained. In addition, according to this embodiment, since the jig 110 is not fixed to the outer peripheral surface 9a of the die 9, it is not necessary to remove the heater 19 during maintenance. Also, the jig 110 can be fixed to the die 9 at all times (for example, during molding).

One aspect of the present invention has been described above based on the third embodiment.

(Fourth embodiment)
FIG. 18 is a cross-sectional view showing a die device 2 according to a fourth embodiment. The description will focus on differences from the first embodiment.

The jig 110 includes one shaft portion 120 and a fixing portion 130 . The fixing part 130 is formed in a disc shape. Note that the shape of the fixing portion 130 is not particularly limited. The fixed part 130 is fixed to the bottom surface 9b of the die 9 with screws or the like. The shaft portion 120 is fixed to the fixed portion 130 . That is, the shaft portion 120 is fixed to the bottom surface 9 b of the die 9 via the fixing portion 130 . Both ends of the shaft portion 120 protrude outward from the die lip drive mechanism 16 in the radial direction of the die 9 .

According to the present embodiment described above, the same effects as those of the first embodiment can be obtained. According to this embodiment, since the jig 110 is not fixed to the outer peripheral surface 9a of the die 9, it is not necessary to remove the heater 19 during maintenance.

One aspect of the present invention has been described above based on the fourth embodiment.

Next, a modification common to each embodiment will be described.

The configuration of the die lip driving mechanism 16 is not limited to that of the embodiment. For example, the die lip driving mechanism 16 may be configured with a heat bolt that incorporates a heater and expands in the axial direction when heated by the heater. The amount of expansion of the heat bolt is controlled by the amount of power supplied to the heater. When the heat bolt expands, its tip presses the pressure receiving surface 23, thereby adjusting the lip width. In this case, the shaft protrudes outward in the radial direction of the die 9 beyond the die lip driving mechanism 16 having the heat bolt.

In the first and second embodiments, the case where the jig 110 includes two shaft portions, the first shaft portion 121 and the second shaft portion 122, is described, but the jig 110 is not limited to this. Only one of the shafts may be provided. In the third embodiment, the case where both ends of the shaft portion 120 of the jig 110 protrude radially outward from the die lip drive mechanism 16 has been described. Only the part may protrude outside the die lip drive mechanism 16 . In these cases, the shaft is cantilevered, and the die 9 is turned upside down by rotating the cantilevered shaft by 1/2.

In the embodiment, the case where the die 9 is reversed by rotating the shaft portion using the rotary drive device has been described, but the present invention is not limited to this. For example, a hanger such as a chain may be fixed to the surface of the die 9 and the discharge port 18a of the die 9, and the die 9 may be turned over about the shaft portions 121 and 122 by pulling up the hanger.

Any combination of the embodiments and modifications described above is also useful as an embodiment of the present invention. A new embodiment resulting from the combination has the effects of the combined embodiment and modifications.

Reference Signs List 1 inflation molding device 3 die lip driving mechanism 100 die reversing device 110 jig 121 first shaft 121a first projecting portion 122 second shaft 122a second projecting portion.

Claims (9)

A die device for inflation molding,
A die for extruding resin into a tubular shape,
a die lip drive mechanism for adjusting lip width fixed around the lip of the die;
a shaft fixed to the die and protruding further than the die lip drive mechanism in the radial direction of the die ,
A die device , wherein the die is reversed by rotating the shaft . the shaft includes a first shaft fixed to the die and a second shaft fixed to the die substantially coaxially with the first shaft;
2. The die device according to claim 1, wherein the first shaft portion and the second shaft portion protrude further than the die lip drive mechanism in the radial direction of the die. a fixing portion for fixing the shank to the die;
3. The die device according to claim 1, wherein the fixed portion is fixed to the outer peripheral surface of the die. 4. The die apparatus according to claim 3, wherein the fixed portion is also fixed to the surface of the die opposite to the surface on which the discharge port is formed. The fixed part includes a cylindrical part surrounding the outer peripheral surface of the die,
5. The die apparatus according to claim 3, wherein the shaft portion is attached to the cylindrical portion. 3. The first shaft portion and the second shaft portion are each provided with a block that engages with a recess formed in an outer peripheral surface of the die at an end on the die side. 3. The die apparatus according to 2. The shaft portion is fixed to the die so that the extension of the central axis passes through the center of gravity of the die, the center of gravity of the object when the die and the fixing portion are regarded as one object, or their vicinity. 7. The die apparatus according to any one of claims 1 to 6, characterized in that: 2. The die device according to claim 1, wherein both ends of the shaft portion protrude beyond the die lip drive mechanism in the radial direction of the die. A jig used for maintenance of a die to which a die lip drive mechanism for adjusting the lip width is fixed,
A jig characterized by comprising a shaft fixed to the die and protruding further than the die lip drive mechanism in the radial direction of the die, wherein the die is reversed by rotating the shaft . equipment.

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