JP4634936B2 - Vacuum forming roll for producing bubble sheet - Google Patents

Description

  The present invention relates to a vacuum forming roll used when producing a bubble sheet.

Conventionally, a cap sheet provided many cap-shaped projections, and the bubble sheet body formed by bonding the flat bar Tsu Kushito is widely used as such a buffer packaging material or heat insulating material. For example, the following manufacturing methods are known.

  A sheet material for cap sheet, which is sequentially supplied from the cap sheet die in a thermoplastic state, is sent to a vacuum forming roll connected to a vacuum exhaust device. On the outer peripheral surface of this vacuum forming roll, a large number of suction cavities for forming bubbles are recessed, and a cap sheet having a number of cap-shaped protrusions corresponding to the shape of the suction cavities is continuously formed by vacuum suction. Form. On the other hand, the backsheet sheet material sequentially supplied in the thermoplastic state from the backsheet die is pressed against the cap sheet by a pressure roll. As a result, the back sheet is sequentially bonded to the back surface of the cap sheet, and a bubble sheet body having a two-layer structure is continuously generated.

As the vacuum forming roll, the suction cavities, the suction side holes formed from one end to the other end of the roll body and opened at both ends, and the suction cavities provided on the bottom wall of each suction cavity are respectively A suction hole that communicates with a corresponding suction side hole and is configured so that both ends of the suction side hole can be connected to a vacuum exhaust device is known. As a specific example of the suction hole, a plurality of small through holes are provided in the bottom wall of the suction cavity, and the suction hole is configured by these small through holes, or the bottom wall of the suction cavity is separated from the roll body. An embodiment in which the suction hole is formed by a cut-off portion such as a slit provided in the plug and formed by the formed plug is exemplified (see, for example, Patent Document 1).
Japanese Unexamined Patent Application Publication No. 2004-188608 (see FIGS. 1 to 4)

  However, since the conventional vacuum forming rolls are set to the same value regardless of the distance from each region to the vacuum exhaust device, the opening ratio of the suction holes in the end region and the central region of the roll body is Of the main body, the suction force in the central region far from the vacuum evacuation device is relatively weaker than the suction force in both end regions near the vacuum evacuation device, and as a result, the projections in the central region are incompletely molded. In some cases, the product value of the air bubble sheet is impaired. Such problems are caused by the fact that the vacuum forming roll is wide to produce a wide bubble sheet from the viewpoint of improving the production efficiency, or the rotation speed of the vacuum forming roll is increased to further improve the production efficiency. This is particularly likely to occur.

  Further, due to the above-described difference in suction force, the thickness of the projection formed in the central region of the vacuum forming roll is different from the thickness of the projection formed in the end region of the vacuum forming roll, and the product is homogeneous. There is also a problem that it cannot be realized.

  In addition, with the diversification of usage modes of the bubble sheet, there is a desire to change the width dimension of the bubble sheet to be molded. In order to meet such a demand, when forming a bubble sheet body having a width smaller than the width of the vacuum forming roll using a conventional vacuum forming roll having the same opening ratio of each suction hole, vacuum forming There is a problem that air easily flows through the suction holes of the suction cavity in the end region of the roll, and a sufficient suction force cannot be obtained in the central region. For this reason, conventionally, it has been necessary to make complicated equipment changes such as replacing the vacuum forming rolls one by one in correspondence with the width dimension of the foam sheet body to be formed, and there has been a problem that the production efficiency is poor.

  In addition, the troubles enumerated above may occur in a similar manner when the vacuum forming roll is configured to connect only one end of the suction side hole to the vacuum exhaust device. In this case, the above-described problem is caused by the suction force of the end region on the side of the roll body not connected to the vacuum exhaust device being weaker than the suction force of the end region on the side connected to the vacuum exhaust device. It is.

  The present invention has been made paying attention to such problems, and the main purpose is to equalize the suction force in the entire area of the roll body, improve the production efficiency and equalize the thickness, and further, An object of the present invention is to provide a vacuum forming roll for producing a bubble sheet body that can flexibly cope with a width change.

That is, the vacuum forming roll for manufacturing the bubble sheet body of the present invention was formed from one end to the other end of the roll body, and a plurality of bubble forming suction cavities provided on the outer peripheral surface of the roll body. A plurality of suction side holes, and a plurality of suction holes provided on the bottom wall of each suction cavity and communicating with the corresponding suction side holes, and both ends of the suction side holes; the be of construction which is connected to a vacuum exhaust device, the bottom wall of the suction cavity constituted by a plug which forms the roll body and separately, the suction by at least one of the cutouts and the small through-hole provided in the plug constitute a hole, by changing at least one of the number and the form of the suction hole, the aperture ratio of the suction holes in the end region of the opening ratio of the suction holes in the central region of the roll body Characterized in that is also set to a large value.

  If it is such, by setting the aperture ratio of the suction hole in the central area of the roll body to a value larger than the aperture ratio of the suction hole in the end area, the central area and the end area of the roll body Thus, the difference in suction force that can occur between the two regions is corrected to make the suction force in each region uniform, thereby preventing defective products due to insufficient suction. As a result, it is possible to increase the rotational speed of the vacuum forming roll, and it is also possible to make the vacuum roll wider, thereby effectively improving the production efficiency of the bubble sheet body. Furthermore, since the suction force in the central region and the end region of the roll body is made uniform, the thickness of each protrusion formed on the bubble sheet body can be made uniform, which contributes to the homogenization of products.

  In addition, the opening rate of the suction holes in the central region of the roll body is set to a value larger than the opening rate of the suction holes in the end region, in other words, suction of the end region of the roll body. This means that the aperture ratio of the holes is set to a value smaller than the aperture ratio of the suction holes in the central region, and this is a case where a bubble sheet having a width smaller than the width of the roll body is formed. In addition, the air inflow from the suction cavity in the end region of the vacuum forming roll can be suppressed as much as possible, and a sufficient suction force in the central region can be secured. Thus, it is possible to flexibly cope with the formation of a bubble sheet having a small width without requiring complicated equipment changes such as replacement of the vacuum forming roll itself.

In addition, the vacuum forming roll for manufacturing the inventive sheet according to the present invention is formed from a suction cavity for air bubble forming recessed in the outer peripheral surface of the roll body, and from one end to the other end of the roll body. A plurality of suction side holes, and a plurality of suction holes provided on the bottom wall of each suction cavity and communicating with the corresponding suction side holes, and one end of the suction side hole. The bottom wall of the suction cavity is formed by a plug that is separate from the roll body, and at least a cut-out portion and a small through hole provided in the plug are configured. one constitutes the suction holes by, by changing at least one of the number and the form of the suction hole, the end territory on the side which is not connected to a vacuum exhaust device of the roll body The opening ratio of the suction holes of the is characterized in that it has set to a value larger than the opening ratio of the suction holes in the end region of the side connected to the evacuation device.

  If this is the case, the suction force of the end region on the side of the roll body that is not connected to the vacuum evacuation device, even in such a configuration that only one end of the suction horizontal hole can be connected to the evacuation device, By equalizing the suction force of the end region on the side connected to the vacuum exhaust device, it is possible to improve production efficiency and homogenize products, and also to manufacture a bubble sheet body with a narrow sheet width It can respond flexibly.

  In particular, if each of the regions is further divided into a plurality of small regions arranged in the axial direction of the roll body, and the opening rate of the suction hole is varied step by step in units of the small regions, suction is performed. It is possible to further increase the uniformity of force, and to have excellent high-speed productivity and variable width.

  Here, the “removal part” includes notches obtained by notching a part of the plug, and notches such as slits. Further, the “form” of the excision part and the small through-hole is the shape of the excision part and the small through-hole, and specifically means the shape and size of the excision part and the small through-hole.

  As described above, according to the present invention, since the opening ratio of the suction holes in the central area of the roll body is set to a value larger than the opening ratio of the suction holes in the end area, The suction force in the region and the end region is made uniform, the rotational speed of the forming roll can be increased, and the production efficiency of the bubble sheet can be increased. In addition, the thickness of each protrusion formed on the bubble sheet body can be made uniform, and the sheet width can be flexibly dealt with without requiring complicated equipment changes such as replacing the vacuum forming roll itself. Can do.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for explaining the present invention will be described with reference to the drawings.

  A vacuum forming roll R for producing a bubble sheet body according to the present embodiment constitutes a part of the bubble sheet body forming machine X shown in FIG. 1, and as shown in FIGS. The roll main body R1, the rotation shaft R2 provided so as to penetrate the roll main body R1, and an urging means RS such as a spring are urged toward the roll main body R1 and are attached to both ends of the roll main body R1 with a constant pressure. A pair of side plates R3 in contact with each other is provided. The rotation shaft R2 is supported by a bearing (not shown).

  The roll body R1 includes a plurality of bubble forming suction cavities R11 that are recessed in the outer peripheral surface, and a plurality of suction side holes R12 that are formed from one end to the other end of the roll body R1 and open at both ends. A suction hole R13 is provided on the bottom wall of each suction cavity R11, and communicates the suction cavities R11 with the corresponding suction lateral holes R12.

  As shown in FIG. 3 and the like, each suction cavity R11 has a bottom having a substantially trapezoidal shape in cross section. In this embodiment, such suction cavities R11 are staggered on the outer peripheral surface of the roll body R1. Provided.

  Each suction lateral hole R12 is substantially linear and extends along the axial direction of the roll body R1, and the plurality of suction lateral holes R12 are separated by a predetermined pitch along the circumferential direction of the roll body R1. It is provided. In the present embodiment, both ends of each suction lateral hole R12 are configured to be connected to the vacuum exhaust device V.

  As shown in FIGS. 3 and 4, the suction hole R13 is constituted by a small through hole R11a provided in the bottom wall of the suction cavity R11. The small through hole R11a extends from the bottom wall of each cavity R11 toward the axis of the roll body R1 and communicates with the suction side hole R12. In the present embodiment, as shown in FIG. 4, each small through-hole R11a (that is, the suction hole R13) provided in the bottom wall of the plurality of rows of suction cavities R11 adjacent along the circumferential direction of the roll body R1 has a common suction. It communicates with the horizontal hole R12 for use.

  Thus, the vacuum forming roll R according to the present embodiment changes the number of the small through-holes R11a and the form thereof to change the opening ratio of the suction hole R13 in the central region R1C of the roll body R1 to the end region of the roll body R1. It is set to a value larger than the opening ratio of the suction hole R13 of R1E. In the present embodiment, as shown in FIG. 5, the number of small through holes R11a constituting the suction hole R13 of the central region R1C is set to be smaller than the number of small through holes R11a constituting the suction hole R13 of the end region R1E. (In the figure, the number of small through holes R11a constituting the suction hole R13 of the central region R1C is four, and the number of small through holes R11a constituting the suction hole R13 of the end region R1E is two. In this example, the aperture ratio of the suction hole R13 in the central region R1C is set to a value larger than the aperture ratio of the suction hole R13 in the end region R1E. FIG. 5 illustrates an example in which the small through hole R11a is a hole having a substantially circular shape in plan view.

  The side plate R3 includes a vacuum port R31 (so-called “vacuum zone”) leading to the vacuum exhaust device V and an atmospheric pressure port R32 leading to the atmosphere, as shown in FIGS. When the vacuum forming roll R is rotated, a plurality of suction side holes R12 that come to communicate with the vacuum port R31 along the axial direction of the roll body R1 are evacuated through the vacuum port R31. It is connected to V so as to be vacuumed. The vacuum forming roll R of the present embodiment is configured so that both ends of each suction lateral hole R12 can be connected to the vacuum exhaust device V via the vacuum port R31 of the corresponding side plate R3.

  The rotary shaft R2 is hollow, and a heat medium that cools the roll body R1 from the inside can be circulated using the hollow.

  Next, a method and an action of manufacturing the bubble sheet S using the bubble sheet forming machine X equipped with such a vacuum forming roll R will be described with reference to FIG.

  First, the film-shaped cap sheet material SCa in a thermoplastic state is sequentially supplied from the cap sheet die D1 to the rotating vacuum forming roll R, and vacuum suction of the vacuum forming roll R connected to the vacuum exhaust device V is performed. By the action, the cap sheet SC having a large number of projections SC1 corresponding to the shape of the suction cavity R11 is continuously formed. At this time, since the aperture ratio of the suction hole R13 in the central region R1C of the roll body R1 is set to a value larger than the aperture ratio of the suction hole R13 in the end region R1E, each region (central region R1C, end The suction force in the partial region R1E) is made uniform, and each projection SC1 is accurately molded. On the other hand, a film-like backsheet sheet material SBa in a thermoplastic state is sequentially supplied from the backsheet die D2 to the vacuum forming roll R, and the backsheet sheet material SBa is supplied to the cap sheet SC by a pressure roll RA. Press on the back side of and paste. As a result, a two-layered bubble sheet S having a large number of bubbles sealed in a sufficient vacuum state is formed from the cap sheet SC and the back sheet SB, and then peeled from the vacuum forming roll R by the peeling roll RB. Then, it shifts to the pinch roll RC, and becomes a finished product through a predetermined process (cutting process or the like).

  As described above, in the vacuum forming roll R according to the present embodiment, the opening rate of the suction hole R13 in the central region R1C of the roll body R1 is set to a value larger than the opening rate of the suction hole R13 in the end region R1E. Therefore, the suction force in the central region R1C and the end region R1E of the roll body R1 is made uniform, and a sufficient suction force can be obtained in each region R1C, R1E, so that each projection SC1 can be accurately molded. it can. As a result, even when the rotation speed of the vacuum forming roll R is increased, it is possible to prevent conventional defects, that is, defective commercialization due to insufficient suction force, and dramatically increase the production efficiency of the bubble sheet S. Can be improved.

  In addition, the thickness of each protrusion SC1 formed on the bubble sheet S can be made uniform by equalizing the suction force in the central region R1C and the end region R1E of the roll body R1. It is also possible to effectively homogenize products.

  Furthermore, since the aperture ratio of the suction hole R13 in the end region R1E of the roll body R1 is set to a value smaller than the aperture ratio of the suction hole R13 in the center region R1C, the width dimension is smaller than the width dimension of the roll body R1. Even when the air bubble sheet S is molded, the air flow through the suction cavity R11 in the end region R1E of the vacuum forming roll R is suppressed, and a sufficient suction force in the central region R1C is secured. be able to. In this way, it is possible to flexibly cope with sheet width changes without requiring complicated equipment changes such as replacement of the vacuum forming roll R itself.

  In particular, the suction hole R13 is composed of a plurality of small through holes R11a provided in the bottom wall of the suction cavity R11, and the aperture ratio is changed by changing the number of these small through holes R11a. The difference in the opening ratio of the suction hole R13 in each region R1C, R1E can be realized by the configuration.

In the embodiment of the present invention , the bottom wall of the suction cavity XR11 is constituted by a plug XP that is separate from the roll body XR1, instead of the structure described in detail above , that is, the structure having no plug. In addition, the suction hole XR13 is provided by the cut portion XPa provided in each plug XP.

Further, each of the regions R1C and R1E is further divided into a plurality of small regions arranged in the axial direction of the roll main body R1, and the opening ratio of the suction hole R13 is changed stepwise for each small region. Good. By adopting such an aspect, it is possible to further increase the uniformity of the suction force in each of the regions R1C and R1E.
Next, specifically described with reference to FIGS. 5 to 7 for the embodiment of a vacuum forming roll according to the present invention.

The vacuum forming roll XR according to the present invention is substantially the same as the vacuum forming roll R according to the above embodiment except for the structure of the suction cavity XR11 and the configuration of the suction hole XR13. X is attached to the head of the corresponding code, and detailed description is omitted.

Each of the suction cavities XR11 has a bottom having a substantially trapezoidal shape in cross section as shown in FIGS. 6 and 7, and further extends from the bottom wall of each suction cavity XR11 toward the axis of the roll body XR1. A vacuum passage XR111 communicating with the suction side hole XR12 is provided. In the present embodiment , the vacuum passages XR111 of the plurality of rows of suction cavities XR11 adjacent in the circumferential direction of the roll body XR1 communicate with the common suction side hole XR12.

Vacuum forming roll XR according to this embodiment, the bottom wall of the suction cavity XR11 constituted by a plug XP forming a separate roll body X R1, constitute a suction hole XR13 by cutouts XPa provided in each plug XP Yes.

  The plug XP is a thin plate formed of a metal material such as phosphor bronze, and has a shape that fits into the bottom wall of the suction cavity XR11.

Accordingly, the opening ratio of the suction hole XR13 in the central region XR1C of the roll body XR1 is set to a value larger than the opening ratio of the suction hole XR13 in the end region XR1E of the roll body XR1. In the present embodiment , the aperture ratio is varied by changing the number and form (shape and size) of the cut portions XPa provided in the plug XP. As an example, as shown in FIGS. 5C and 5D, the suction hole XR13 of the central region XR1C is formed into four straight lines extending from the outer edge of four equiangular points toward the center of the plug XP. The suction hole XR13 of the end region XR1E is constituted by eight straight slits (removal portions XPa) extending from the outer edges of eight equiangular positions toward the center of the plug XP. What is configured is mentioned.

  Even in the vacuum forming roll XR having such a configuration, the opening rate of the suction hole XR13 in the central region XR1C of the roll body XR1 is larger than the opening rate of the suction hole XR13 in the end region XR1E of the roll body XR1. Therefore, the suction force in each of the regions XR1C and XR1E is made uniform, and substantially the same effect as the vacuum forming roll R according to the embodiment can be obtained.

Incidentally, FIG. 5 (c), in the embodiment (d), the opening ratio of the suction holes X R13 end region X R1E the opening ratio of the suction holes X R13 in the central region X R1C roll body X R1 In order to set a larger value than the above, the number of slits serving as the cut portions XPa provided in the plug XP is exemplified. However, the present invention is not limited to this. For example, the same number of cut portions in the regions XR1C and XR1E is used. On the other hand, the opening ratios of the suction holes XR13 of the regions XR1C and XR1E may be made different by changing the shapes of the cut portions in the regions XR1C and XR1E, respectively. Further, as the cut-off portion XPa, in addition to slits, substantially V-shaped or substantially U-shaped cuts (see FIGS. 5 (e) and 5 (f)) formed radially on the outer edge of the plug XP, or plugs You may employ | adopt the substantially cyclic | annular (refer the figure (g)) formed in the outer edge part of XP, or a substantially meniscus notch. Furthermore, you may comprise the suction hole XR13 by combining at least 2 sort (s) among a slit, a notch | incision, or a notch (refer the figure (f), (h)). Further, the plug XP may be formed with one or a plurality of small through holes penetrating in the thickness direction, and the suction hole XR13 may be configured by the small through holes. In this case, the number and form of the respective small through holes, as long as it is within the range of the aperture ratio of the suction holes X R13 in the central region XR1C of the roll body XR1 is larger than the opening ratio of the suction holes XR13 end region XR1E It is not particularly limited. Further, the suction hole XR13 may be configured by a combination of a cut portion XPa provided in the plug XP and a small through hole.

Furthermore, in the above-described embodiment, the vacuum forming roll is configured so that both ends of the suction side hole can be connected to the vacuum exhaust device, but not limited thereto, only one end of the suction side hole is vacuumed. The opening ratio of the suction holes in the end region on the side of the roll body not connected to the vacuum exhaust device is configured so that it can be connected to the exhaust device, and the opening ratio of the suction holes in the end region on the side connected to the vacuum exhaust device It may be set to a larger value. Even in such a case, the suction force in each region of the roll body is made uniform, and the problem that occurs when the aperture ratios of all the suction holes are set to the same, that is, the end on the side not connected to the vacuum exhaust device The suction force in the partial region is weaker than the suction force in the end region on the side connected to the vacuum evacuation device, and various problems such as a reduction in production efficiency can be solved.

In addition, the aspect which makes the opening ratio of the suction hole different in each region is the above-described implementation after adopting the aspect in which the bottom wall of the suction cavity is configured by a plug and the cut portion or the small through hole is formed in the plug. What is necessary is just to follow a form .

  Further, each region may be further divided into a plurality of small regions arranged in the axial direction of the roll main body, and the aperture ratio in units of each small region may be varied stepwise.

  Further, when the suction cavity has a substantially polygonal shape in plan view, the plug constituting the bottom wall of the cavity may be shaped to fit into the cavity.

  In addition to the staggered arrangement, the suction cavities arranged in a large number on the outer peripheral surface may be arranged in a reverse staggered arrangement in which the zigzag arrangement is inclined by 90 degrees, or a lattice arrangement, or an oblique arrangement in which the staggered arrangement is inclined by 15 to 45 degrees For example, various types may be used.

In the above embodiment, the suction holes of the suction cavities in the plurality of rows adjacent to each other along the circumferential direction of the roll body are illustrated as communicating with the common suction horizontal hole. You may employ | adopt the aspect connected to the corresponding one horizontal hole for suction, respectively.

  In addition, the bubble sheet produced using the vacuum forming roll according to the present invention may be a two-layered product that includes a cap sheet and a back sheet and can be used as a packing material or the like, or a cap sheet. It may be an intermediate molded product formed in the process of manufacturing a three-layered hollow plate that can be used as an automobile interior material or the like by further attaching a liner sheet to the surface side (the top side of each protrusion).

  In addition, the specific configuration of each part is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

The figure which shows typically the molding machine provided with the vacuum forming roll which concerns on embodiment for demonstrating this invention. The whole perspective view of the vacuum forming roll concerning the embodiment. The figure which shows typically the front view of the vacuum forming roll which concerns on the same embodiment, with a partial cross section. The figure which shows typically the principal part expanded cross section of the vacuum forming roll which concerns on the same embodiment. The figure which shows the various aspects of the suction hole of the vacuum forming roll which concerns on the embodiment and embodiment of this invention . The figure which shows the vacuum forming roll which concerns on embodiment of this invention corresponding to FIG. The figure which shows the vacuum forming roll which concerns on embodiment of this invention corresponding to FIG.

Explanation of symbols

R, XR ... vacuum forming rolls R1, XR1 ... roll body R11, XR11 ... suction cavity R11a ... small through-hole R12, XR12 ... suction side hole R13, XR13 ... suction holes R1C, XR1C ... central region R1E, XR1E ... end Part region V ... Vacuum exhaust device XR111 ... Vacuum passage XP ... Plug XPa ... Cutting part

Claims (3)

A suction cavity for bubbles forming, which is a large number recessed on the outer peripheral surface of the roll body, a suction transverse holes formed across from one end to the other end of the roll body, a plurality in the bottom wall of each suction cavity each provided it comprises a suction hole for communicating their suction cavity suction transverse holes respectively corresponding, at both ends of the suction transverse bore be of construction which is connected to a vacuum exhaust device,
The bottom wall of the suction cavity is configured by a plug that is separate from the roll body, and the suction hole is configured by at least one of a cutout portion and a small through hole provided in the plug,
By changing at least one of the number and form of the suction holes,
A vacuum forming roll for producing a bubble sheet body, characterized in that the opening rate of the suction holes in the central region of the roll body is set to a value larger than the opening rate of the suction holes in the end region. A suction cavity for bubbles forming, which is a large number recessed on the outer peripheral surface of the roll body, a suction transverse holes formed across from one end to the other end of the roll body, a plurality in the bottom wall of each suction cavity each provided it comprises a suction hole for communicating the suction transverse holes corresponding to those of the suction cavity, respectively, only one end of the suction transverse bore be one configured so as to connect to the evacuation device And
The bottom wall of the suction cavity is configured by a plug that is separate from the roll body, and the suction hole is configured by at least one of a cutout portion and a small through hole provided in the plug,
By changing at least one of the number and form of the suction holes,
The opening ratio of the suction holes in the end region on the side not connected to the vacuum exhaust device of the roll body is set to a value larger than the opening ratio of the suction holes in the end region on the side connected to the vacuum exhaust device. A vacuum forming roll for producing a bubble sheet body. 3. Each of the regions is further divided into a plurality of small regions arranged in the axial direction of the roll body, and the opening ratio of the suction holes is made to vary stepwise in units of the small regions. A vacuum forming roll for producing the air bubble sheet described above.

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