JP4136985B2 - Bonded blow molded article and method for producing the same. - Google Patents

Description

  The present invention relates to a bonded blow molded article in which a skin sheet such as a nonwoven fabric is integrally bonded to the surface of a blow molded article, and a method for producing the same.

Bonded blow molded products are used for applications where appearance is important, such as panels used in automobile interiors and furniture, and panels used in partition boards, so it is necessary to clean the peripheral edge of the skin sheet. .
In general, the skin sheet covers from the front side of the blow molded body to the parting line, and an extra part is cut off along with the parison (part of the burr after splitting) in the parting line. This excision is usually performed manually using a knife or scissors, but if this is not done carefully, the skin sheet near the parting line will be scratched and the edges will become fuzzy and the appearance will deteriorate. Especially when a thick non-woven fabric is used as the skin sheet, the non-woven fabric adhered to the surface of the blow molded product rises on the surface of the blow molded product. It is difficult and extremely laborious to do.
On the other hand, in Patent Documents 1 and 2 below, by bringing the parting line to the back side that is not touched by the human eye, it is easy to process the end of the skin sheet, and a bonded blow molded article with a good appearance is manufactured. It is disclosed.

On the other hand, without covering the skin sheet to the parting line, it may be bonded to the front side (panel surface of the panel) of the blow molded body, leaving an edge (unbonded portion) around the periphery. In this case, the skin sheet is generally a cloth such as a flexible non-woven fabric. Therefore, the cutting is often inaccurate, or is often displaced or distorted during blow molding. Or the appearance will deteriorate. Moreover, since the outer peripheral edge of the skin sheet is exposed on the front side (panel surface of the panel) of the blow-molded product, a hand or the like hits it during use, and it tends to fluff or peel off.
On the other hand, Patent Document 3 below describes that an annular protrusion protruding into the cavity is formed on the inner surface of the mold cavity, and a skin sheet is disposed inside the protrusion to perform blow molding. Furthermore, Patent Documents 4 and 5 below describe that the skin sheet is held by needle-like protrusions or hook-like hairs installed on the mold side to prevent positional displacement in the mold.

JP-A-8-118459 JP 2003-145612 A JP-A-8-294957 JP-A-8-323849 JP-A-9-11324

However, in the methods of Patent Documents 1 and 2, it is necessary to finish the end portion of the skin sheet, and in this method, the skin sheet is bonded to a part of the front side (panel surface of the panel) of the blow molded body. Not applicable in some cases.
On the other hand, the methods of Patent Documents 3 to 5 are ordinary nonwoven fabrics that are not particularly long when the skin sheets are not very accurate, or when they are slightly misaligned when placed on the inner surface of the mold cavity. In the case of a skin sheet such as the above, the shift of the outer peripheral line of the skin sheet and the meandering are conspicuous and the appearance is deteriorated. In addition, since the periphery of the bonding surface is surrounded by a stepped edge portion, the outer peripheral edge of the skin sheet is difficult to peel off during use, but on the other hand, the cross-sectional structure of the blow molded body is limited in this respect. .

  The present invention has been made in view of the problems of such a conventional bonded blow-molded product and a method for producing the same, and does not require finishing of the end portion of the skin sheet after blow molding. It is an object of the present invention to obtain a bonded blow-molded product that is free from misalignment and meandering and that can prevent the outer peripheral edge of the skin sheet from peeling off during use.

  The method for producing a bonded blow-molded body according to the present invention comprises arranging a skin sheet along the cavity inner surface of a blow molding die, closing the blow molding die, sandwiching a parison, performing blow molding, and blowing in the die. The skin sheet is integrally bonded to the surface of the molded body, and the blow molding die has an annular rib protruding into the cavity around a portion corresponding to the bonding surface of the blow molded body on the inner surface of the cavity. . In the production of this bonded blow molded article, the skin sheet is disposed inside the rib, and the peripheral edge of the skin sheet is bent toward the inside of the cavity along the inner surface of the rib, and in that state, the blow molding die Is closed, the parison is sandwiched, and blow molding is performed. The bonded blow molded article produced by this method is formed with an annular groove recessed inward around the bonded surface of the skin sheet, and the peripheral edge of the skin sheet enters the groove, and the inner surface thereof. Are pasted together.

  In the manufacturing method, the rib is disposed so as to freely advance and retract toward the inside of the cavity of the blow molding die, and the rib is blown by blowing air to the surface of the blow molding die or its surface. It can be moved back to the vicinity. In this case, the annular groove formed in the blow-molded body by the rib is crushed in the width direction by the air pressure due to the retreat of the rib, and in particular, the width of the groove is narrowed in the vicinity of the surface of the blow-molded body. The peripheral edge is sandwiched.

The manufacturing method can be applied particularly suitably when the blow-molded body is a panel having a double wall structure, the outer peripheral portion of the plate surface of the panel is used as an edge portion, and the skin sheet is bonded to the inside thereof. In this case, in the blow molding die, the rib is formed in an annular shape on the inner surface of the cavity for molding the plate surface of the panel.
In the manufacturing method described above, the material of the peripheral edge of the skin sheet (for example, four corners in the case of a quadrangular skin sheet) can be cut in advance in order to prevent wrinkling.

According to the bonded blow-molded body of the present invention, the peripheral edge portion of the skin sheet fits into the groove of the blow-molded body formed by the ribs and is bonded to the inner surface thereof. There is no need to cut the part with a knife or scissors. In addition, the position of the end line of the skin sheet does not shift and the end line does not meander, so the appearance is excellent, and the outer periphery of the skin sheet does not fluff or peel off during use. . Furthermore, even if the cutting of the skin sheet is somewhat inaccurate, or even if it is slightly misaligned when placed in the cavity of the mold, the peripheral edge is fitted in the groove, so that the appearance is not affected.
In the present invention, even when the skin sheet is bonded to the entire surface of the panel as in Patent Documents 1 and 2, when the peripheral sheet is bonded to the center portion around the panel surface as in Patent Documents 3 to 5. It can also be applied to. And since it is not necessary to make a edging part one step higher, it can apply to the bonded blow molded object of various forms.

In the bonded blow molded article of the present invention, when the groove formed in the blow molded article is crushed and the peripheral edge of the skin sheet that has entered the groove is sandwiched, the peeling of the edge of the skin sheet is further prevented. And the appearance is excellent.
The present invention is particularly suitable for the production of double-walled panels, and the skin sheet is bonded to one or both surfaces of the panel. As the skin sheet, a cloth such as a non-woven fabric and other sheets can be used as is well known.

Hereinafter, with reference to FIGS. 1-12, the bonded blow molded object which concerns on this invention, and its manufacturing method are demonstrated concretely.
A bonded blow molded body 1 shown in FIG. 1 is obtained by bonding a skin sheet 3 made of a nonwoven fabric to both surfaces of a blow molded body 2. The blow-molded body 2 is a substantially quadrangular panel having a double wall structure, and an edge portion 4 and a central bonding portion 5 are formed on both sides, and an annular groove 6 having a substantially square shape in plan view is formed therebetween. . The skin sheet 3 is bonded to the blow-molded body 2 on the surface (bonding surface) of the bonded portion 5, and its peripheral portion enters the groove 6, and the peripheral portion is bonded to the inner surface of the groove 6. Yes.

  3 to 5 show a method for manufacturing the bonded blow-molded body 1. In FIG. 3, annular ribs 9 are formed on the cavity inner surfaces of the pair of blow molding dies 7 and 8 so as to protrude around a portion corresponding to the bonding portion 5 of the blow molded body 2. A substantially quadrangular skin sheet 3 is disposed inside the rib 9, and its peripheral edge is bent along the inner surface of the rib 9 into the cavity. In this skin sheet 3, as shown in FIG. 6, the material of the four corners is cut in advance into a quadrangular shape. This is because the peripheral portion is bent toward the inside of the cavity without causing wrinkles, and further, it is possible to suppress wrinkling at the corner portion of the skin sheet in the product after blow molding.

A plastic parison 11 is lowered between the pair of blow molds 7 and 8, and then, as shown in FIG. 4, clamping is performed. As the mold is clamped, the air in the parison 11 is compressed, and the parison 11 is lightly pressed against the inner surfaces of the cavities of the blow molding dies 7 and 8. After clamping, as shown in FIG. 5, pressurized air is blown into the parison 11 from a nozzle (not shown) to perform blow molding. As a result, the parison 11 is strongly pressed against the inner surface of the cavity of the blow molding dies 7, 8, and is formed into a panel shape along the inner surface of the cavity. On the other hand, the skin sheet 3 is pressed by the parison 11 and pressed against the cavity inner surfaces (including the surfaces of the ribs 9) of the blow molding dies 7 and 8, and is compressed and thinned. The parison 11 (blow molded body 2) and the skin sheet 3 are bonded together by the pressure at this time.
After blow molding, when the air is extracted and the mold is opened, the skin sheet 3 swells to its original thickness, and if a burr is cut off at the parting line, the bonded blow molded body 1 shown in FIGS. If the width of the rib 9 is reduced, the width of the groove 6 is reduced, and although depending on the thickness of the skin sheet 3, the groove 6 is buried in the swelled skin sheet 3 so that it is not noticeable in appearance, and further on the appearance. It can be made completely invisible.

  A bonded blow-molded body 21 shown in FIG. 7 is obtained by bonding a skin sheet 23 made of a nonwoven fabric to one surface of a blow-molded body 22. The blow-molded body 22 is a substantially quadrangular panel in plan view having a double wall structure, and has an annular portion 24 and a central bonding portion 25 on one side (upper surface) of the panel, and a substantially rectangular annular shape in plan view therebetween. A groove 26 is formed, and the other surface (lower surface) of the panel is composed of a peripheral protrusion 33 and a flat surface 34 on the inside. The groove 26 is crushed in the width direction, and its width is large at the bottom, but narrows in the vicinity of the panel surface. The skin sheet 23 is bonded to the blow-molded body 22 on the surface (bonding surface) of the bonding portion 25, and its peripheral portion enters the groove 26, and the peripheral portion is bonded to the inner surface of the groove 26, Further, it is sandwiched between the crushed grooves 26.

  FIGS. 8-12 shows the manufacturing method of the bonded blow molded object 21. FIG. In FIG. 8, an annular slide plate 29 (may be divided into a plurality of pieces) around the portion corresponding to the bonding portion 25 of the blow molded body 22 is formed on the cavity inner surface of one blow molding die 27. Is installed in the cavity so that it can move forward and backward. At this stage, the slide plate 29 is retracted until its tip end surface is flush with the cavity inner surface of the blow molding die 27. A substantially quadrangular skin sheet 23 is arranged on the inner surface of the cavity of the blow molding die 27 so that the peripheral edge thereof covers the slide plate 29. Note that, similarly to the skin sheet 3 shown in FIG. 6, it is desirable that the material of the four corners is cut in advance for the skin sheet 23.

  Subsequently, as shown in FIG. 9, the slide plate 29 moves forward into the cavity, the tip protrudes into the cavity to form a rib 29 a, and the rib 29 a moves the peripheral edge of the skin sheet 23 into the cavity. Bend in. Instead of this procedure, the slide plate 29 is first moved forward so that the rib 29a protrudes into the cavity, and then the skin sheet 23 is arranged inside the rib 29a as shown in FIG. Also good. The procedure in this case is substantially the same as the procedure for arranging the skin sheet 3 shown in FIG. In FIG. 9, the plastic parison 31 is further lowered between the pair of blow molds 27 and 28, and the mold clamping is started. In the blow molding die 28, reference numeral 35 denotes a nozzle for blowing air.

  As the mold is clamped between the pair of blow molds 27 and 28, the air in the parison 31 is compressed as shown in FIG. 10, and the parison 31 is lightly pressed against the inner surface of the cavity of the blow molds 27 and 28. . Further, after the mold clamping, the nozzle 35 moves forward, the tip penetrates through the wall of the parison 31, reaches the inside of the parison, and pressurized air is blown into the parison 31 from the nozzle to perform blow molding. As a result, as shown in FIG. 11, the parison 31 is strongly pressed against the inner surface of the cavity of the blow molding dies 27, 28, and is molded into a panel shape along the inner surface of the cavity. 26 is formed. On the other hand, the skin sheet 23 is pressed by the parison 31 and pressed against the cavity inner surface (including the surface of the rib 29a) of the blow molding die 27, and is compressed and thinned. The parison 31 (blow molded body 22) and the skin sheet 23 are bonded together by the pressure at this time.

Subsequently, while the blow molding is being performed (while the parison 31 has plasticity and air is blown into the parison 31), the slide plate 29 is retracted to the original position, and the tip surface of the rib 29a Becomes flush with the inner surface of the cavity of the blow molding die 27 and forms part of the inner surface of the cavity of the blow molding die. As a result, as shown in FIG. 12, the parison 31 flows, the grooves 26 are crushed in the width direction, and the skin sheet is sandwiched so as to fill the gap after the rib 29a is removed.
After blow molding, when the air is extracted and the mold is opened, the skin sheet 23 swells to its original thickness, and if a burr is cut off at the parting line, a bonded blow molded body 21 shown in FIG. 7 is obtained. Since the groove 26 is crushed (particularly in the vicinity of the surface), if the thickness of the skin sheet 3 is large to some extent, the groove 26 is hidden by the swelled skin sheet 23 and becomes inconspicuous at all in appearance.

It is a perspective view of the bonded blow molded object which concerns on this invention. FIG. It is sectional drawing explaining the manufacturing method of the bonded blow molded object. It is sectional drawing explaining the manufacturing method similarly. It is sectional drawing explaining the manufacturing method similarly. It is a top view of a skin sheet. It is a partial cross section figure of another bonded blow molded object which concerns on this invention. It is sectional drawing explaining the manufacturing method of the bonded blow molded object. It is sectional drawing explaining the manufacturing method similarly. It is sectional drawing explaining the manufacturing method similarly. It is sectional drawing explaining the manufacturing method similarly. It is sectional drawing explaining the manufacturing method similarly.

Explanation of symbols

1,21 Bonded blow molded body 2,22 Blow molded body 3,23 Skin sheet 6,26 Groove 9,29a Rib 29 Slide plate

Claims (6)

In the bonded blow-molded body in which the skin sheet is integrally bonded to the surface of the blow-molded body at the time of blow molding, the skin sheet is preliminarily cut at the peripheral corner, and the blow-molded body is made of the skin sheet. A bonded blow-molded product, wherein an annular groove recessed inward is formed around a bonded surface, and a peripheral edge portion of the skin sheet enters into the groove and is bonded to the inner surface thereof. The bonded blow-molded article according to claim 1, wherein the groove is crushed in the width direction to sandwich the peripheral edge of the skin sheet. The bonded blow molded article according to claim 1 or 2, wherein the blow molded article is a panel having a double wall structure, and the groove is formed in an annular shape on a plate surface of the panel. Placed skin sheet along the cavity inner surface of the blow molding mold, closed blow molding mold and sandwiched parison, blow molded and bonded blow molding to integrally bond the skin sheet to the surface of the blow molded body In the method for manufacturing a body, the blow molding die includes an annular rib projecting into the cavity around a portion corresponding to the bonding surface of the blow molded body on the inner surface of the cavity, and is formed at a corner of the peripheral edge of the skin sheet. The material is cut, the skin sheet is placed inside the rib, the peripheral edge of the skin sheet is bent along the inner surface of the rib toward the inside of the cavity, and in that state, the blow mold is closed and the parison is closed. A method for producing a bonded blow-molded product, which comprises sandwiching and blow-molding. The rib is disposed so as to be able to advance and retreat toward the inside of the cavity of the blow molding die, and is retracted to the surface of the blow molding die or the vicinity thereof while blowing air and blowing it. The bonded blow molding method according to claim 4, wherein the bonded blow molding method is provided. 6. The blow molded body is a panel having a double wall structure, and the rib is formed in an annular shape on an inner surface of a cavity of the blow molding die for molding a plate surface of the panel. Bonded blow molding method described in 1.

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