JP2018103368A - Blow molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a blow molding that suppresses thinning of a plate thickness due to stretching of a portion in the vicinity of a coupling portion for connecting concave portions formed in a part of a pair of wall surfaces curved in an arc shape in a side view, during blow molding in the vicinity of the coupling portion.SOLUTION: At least a part of a load absorbing member 9 is curved in an arc shape in a side view, and the load absorbing member is a flat blow molding that has a hollow portion 49 formed between an outer peripheral wall 21 disposed on an outer peripheral side and an inner peripheral wall 23 disposed to be spaced apart from the outer peripheral wall 21 toward the inner peripheral side in a thickness direction on an arc-shaped curved cross section in a peripheral direction. A bottom portion 35 of the outer peripheral wall 21 and a bottom portion 43 of the inner peripheral wall 23 are coupled through a coupling portion 47, and the coupling portion 47 is arranged on the outer peripheral side from a thickness direction center CL1 of the outer peripheral wall 21 and the inner peripheral wall 23 opposed to the outer peripheral wall 21.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a blow molded article. More specifically, the present invention relates to a hollow blow molded article obtained by blow molding a resin parison.

  Conventionally, a blow-molded body formed by blow-molding a resin parison is known (for example, see Patent Document 1). The blow molded article in Patent Document 1 is a lid that constitutes a glove box, and includes a pair of front and back walls spaced apart from each other in the thickness direction. Moreover, in order to improve the rigidity of a lid, the recessed part of a U-shaped cross section is formed in the surface wall and a back surface wall, and the bottom parts of the said recessed part are made to contact | abut. The lid is a flat plate extending in a planar shape.

Special table 2007-504037 gazette

  However, when forming the lid by curving it in an arc shape when viewed from the side, if a recess that is recessed toward the back wall is formed on the front wall disposed on the outer peripheral side (convex side), a recess is formed in the flat lid. Compared with the case where it does, the extending | stretching rate of the parison in a recessed part becomes large. Therefore, there has been a problem that the thickness of the concave portion is reduced during blow molding.

  In order to solve the above-described problems, the present invention is provided in the vicinity of a joint portion that joins the respective concave portions formed in a part of a pair of wall surfaces that are curved in an arc shape when viewed from the side. It is an object of the present invention to provide a blow molded article that can suppress the thinning that occurs when the portion is stretched.

  In order to solve the above-mentioned problems, at least a part of the blow molded body according to the present invention is curved in an arc shape when viewed from the side, and is disposed on the outer circumferential side in a cross section along the circumferential direction curved in the arc shape. A flat blow-molded body in which a hollow portion is formed between the outer peripheral wall and the inner peripheral wall that is spaced apart from the outer peripheral wall toward the inner peripheral side in the thickness direction. The outer peripheral wall and the inner peripheral wall are partially connected via a connecting portion, and the connecting portion is disposed on the outer peripheral side with respect to the center in the thickness direction between the outer peripheral wall and the inner peripheral wall facing the outer peripheral wall. Has been.

  In the vicinity of the joint portion of the blow molded body that is curved in an arc shape, there is a problem that the bent portion of the outer peripheral wall is stretched during blow molding and the plate thickness is reduced. Here, in the vicinity of the joint portion, with respect to the stretch ratio at which the bent portion of the outer peripheral wall is stretched during blow molding, the joint portion is disposed on the inner peripheral side with respect to the thickness direction center between the outer peripheral wall and the inner peripheral wall. Compared with the case where the coupling portion is arranged on the outer peripheral side from the center in the thickness direction between the outer peripheral wall and the inner peripheral wall, the coupling portion is arranged on the outer peripheral side from the center in the thickness direction between the outer peripheral wall and the inner peripheral wall. In this case, the stretch ratio of the bent portion of the outer peripheral wall is smaller. Therefore, it is possible to prevent the bent portion of the outer peripheral wall from being stretched during blow molding in the vicinity of the coupling portion, thereby reducing the plate thickness.

It is a perspective view which shows the glove box which concerns on embodiment of this invention. It is a perspective view which shows the load absorption member arrange | positioned in the lid of the glove box of FIG. It is sectional drawing by the AA line of FIG. It is sectional drawing to which the principal part of FIG. 3 was expanded. It is sectional drawing by the BB line of FIG. It is sectional drawing of the initial stage which blow-molds the lid of a glove box. It is sectional drawing of the latter stage which blow-molds the lid of a glove box.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the front side of the vehicle is FR, the rear side is RR, the right side in the vehicle width direction is RH, and the left side in the vehicle width direction is LH.

  As shown in FIG. 1, an instrument panel (not shown) is disposed in the front part of the interior of the automobile. A glove box 1 shown in FIG. 1 is disposed on the passenger seat side which is the left side (LH side) in the vehicle width direction of the instrument panel. The glove box 1 is integrally formed of resin from a lid 3 disposed on the vehicle interior side on the vehicle rear side and a housing portion 5 disposed on the vehicle exterior side on the vehicle front side. In this embodiment, the glove box 1 is accommodated in the accommodation part of the instrument panel, and the form in which the lid 3 is extended along the up-down direction is shown.

  The lid 3 is a plate-shaped member made of resin, and is curved in an arc shape when viewed from the side of the vehicle. Specifically, as shown in FIGS. 1 and 5, the lid 3 includes a lid main body 7 and a load absorbing member 9 (blow molded body) disposed inside the lid main body 7.

  The accommodating portion 5 includes a pair of left and right side surfaces 11 and 11 formed in a triangular shape that tapers downward, a front surface 13 that connects the front edges of the pair of side surfaces 11 and 11 along the vehicle width direction, 13 and a bottom surface 15 disposed on the lower side of the side surfaces 11, 11. The rear edges of the pair of side surfaces 11, 11 are coupled to the back surface of the lid 3. In addition, a rotating shaft 17 projecting sideways is provided at the lower part of the side surfaces 11, 11, and the glove box 1 is configured to be openable and closable (rotatable) in the front-rear direction around the rotating shaft 17. Yes. A stopper 19 is provided on the upper portion of the side surface 11.

  As shown in FIGS. 2 to 5, similarly to the lid 3, the load absorbing member 9 (blow molded body) is formed in a flat shape curved in an arc shape when viewed from the side of the vehicle. Specifically, the outer peripheral wall 21 disposed on the rear side of the vehicle (outer peripheral side, vehicle interior side) and the outer peripheral wall 21 spaced apart from the vehicle front side (inner peripheral side, thickness direction inner side, vehicle interior outer side). An inner peripheral wall 23 that is curved convexly toward the rear side of the vehicle. An extension 25 extending upward is formed at the upper portion of the load absorbing member 9 on the right side in the vehicle width direction, and a tongue piece 27 is provided at the upper end of the left side in the vehicle width direction. And is fixed to the lid body 7.

  As shown in FIGS. 2 and 3, the outer peripheral wall 21 is integrally formed from a wall surface main body portion 31 and an outer peripheral wall-side concave portion 33 that is recessed toward the vehicle front side. The outer peripheral wall side concave portion 33 includes a bottom portion 35 and a side surface portion 37 that extends obliquely while increasing in diameter from the periphery of the bottom portion 35 toward the vehicle rear side (outer peripheral side). The side surface portion 37 is formed in a shape like the side surface of the truncated cone.

  The inner peripheral wall 23 is integrally formed from a wall surface main body portion 39 and an inner peripheral wall side concave portion 41 that is recessed toward the vehicle rear side. The inner peripheral wall-side concave portion 41 includes a bottom portion 43 and a side surface portion 45 that extends obliquely while increasing in diameter from the periphery of the bottom portion 43 toward the vehicle front side (inner peripheral side). The side surface portion 45 is formed in a shape like the side surface of the truncated cone.

  Here, as shown in FIGS. 3 and 4, in the inner peripheral wall side recess 41, the bottom 43 along the extending direction of the inner peripheral wall 23 (the surface direction of the inner peripheral wall 23, the circumferential direction of the inner peripheral wall 23, and the vertical direction). Is W0, and the inner peripheral wall side length at the front end of the side surface portion 45 is W1. Since the side surface portion 45 extends obliquely toward the vehicle front side, the minimum value of the inner peripheral wall side length of the inner peripheral wall side concave portion 41 is set to W0 and the maximum value is set to W1.

  In the outer peripheral wall side recess 33, the length of the bottom 35 along the extending direction of the outer peripheral wall 21 (the surface direction of the outer peripheral wall 21, the circumferential direction of the outer peripheral wall 21, and the vertical direction) is W 0, The outer peripheral wall side length at the rear end is W2. Since the side surface portion 37 extends obliquely toward the rear side of the vehicle, the minimum value of the outer peripheral wall side length of the outer peripheral wall side recess 33 is set to W0 and the maximum value is set to W2. The magnitude relationship between W0, W1, and W2 is set to W0 <W2 <W1. Thus, the maximum value of the inner peripheral wall side length along the circumferential direction in the inner peripheral wall side concave portion 41 is larger than the maximum value of the outer peripheral wall side length along the circumferential direction of the outer peripheral wall side concave portion 33.

  As shown in FIG. 3, the bottom portion 35 of the outer peripheral wall side concave portion 33 and the bottom portion 43 of the inner peripheral wall side concave portion 41 are integrally coupled to form a coupling portion 47. Thereby, a part of the outer peripheral wall 21 and the inner peripheral wall 23 are coupled via the coupling portion 47, and a hollow portion 49 is formed between the outer peripheral wall 21 and the inner peripheral wall 23. Further, the separation direction center CL1 (thickness direction center) between the outer peripheral wall 21 and the inner peripheral wall 23 facing the outer peripheral wall 21 and the radial center C1 of the coupling portion 47 are indicated by alternate long and short dash lines. The coupling portion 47 is disposed on the vehicle rear side (outer peripheral wall 21 side, outer peripheral side) with respect to the separation direction center CL1 (thickness direction center). In addition, side part 45A of the inner peripheral wall side recessed part 41 shown with a dashed-two dotted line in FIG. 4 has shown other embodiment extended in a cylindrical shape with substantially the same diameter toward the vehicle front side. The cross-sectional length of the side surface portion 45A of the inner peripheral wall-side recess 41 according to another embodiment is set longer than the cross-sectional length of the side surface portion 45 according to the present embodiment indicated by a solid line.

  Next, the molding procedure of the load absorbing member 9 (blow molded body) will be described with reference to FIGS.

  First, the mold 51 to be used is composed of a core mold 53 disposed on the lower side of FIG. 6 and a cavity mold 55 disposed on the upper side. On the molding surface 57 of the core mold 53, a core-side convex portion 59 that protrudes upward (cavity mold side) is formed. On the other hand, on the molding surface 61 of the cavity die 55, a cavity-side convex portion 63 that protrudes downward (core die side) is formed. The core-side convex portion 59 and the cavity-side convex portion 63 are disposed at opposing positions. The height of the core-side convex portion 59 is set larger than the height of the cavity-side convex portion 63.

  Then, air is blown into the cylindrical parison to expand it, and the parison is placed on the molding surface 57 of the core mold 53 in a state where the outer peripheral wall 21 and the inner peripheral wall 23 are separated from each other. As shown in FIG. 6, when the core mold 53 is raised and the cavity mold 55 is lowered at the same time, the core-side convex portion 59 and the cavity-side convex portion 63 approach each other.

  Next, as shown in FIG. 7, the core mold 53 is disposed at the top dead center, the cavity mold 55 is disposed at the bottom dead center, and air is further blown into the parison. Then, the outer peripheral wall 21 is pressed against the molding surface 61 of the cavity mold 55, the inner peripheral wall 23 is pressed against the molding surface 57 of the core mold 53, and a part of the outer peripheral wall 21 is pressed downward by the cavity-side convex portion 63. A part of the inner peripheral wall 23 is pressed upward by the core mold 53. As a result, the outer peripheral wall 21 is formed with an outer peripheral wall side concave portion 33 that is recessed toward the inner peripheral side, and the inner peripheral wall 23 is formed with an inner peripheral wall side concave portion 41 that is recessed toward the outer peripheral side. The bottom part 35 of 33 and the bottom part 43 of the inner peripheral wall side recessed part 41 are integrally joined to form a joint part 47.

  Below, the effect by this embodiment is demonstrated.

  (1) The load absorbing member 9 (blow molded body) according to the present embodiment is at least partially curved in an arc shape when viewed from the side, and is disposed on the outer circumferential side in a cross section along the circumferential direction curved in the arc shape. This is a flat blow-molded body in which a hollow portion 49 is formed between the outer peripheral wall 21 and the inner peripheral wall 23 that is spaced from the outer peripheral wall 21 toward the inner peripheral side in the thickness direction. The outer peripheral wall 21 and the inner peripheral wall 23 have bottom portions 35 and 43 (partially) connected to each other via a connecting portion 47, and the thickness direction center between the outer peripheral wall 21 and the inner peripheral wall 23 facing the outer peripheral wall 21. The coupling portion 47 is disposed on the outer peripheral side with respect to CL1.

  In the vicinity of the joint portion 47 of the load absorbing member 9 (blow molded body) curved in an arc shape, there is a problem that the bent portion of the outer peripheral wall 21 is stretched during blow molding and the plate thickness is reduced. Here, in the vicinity of the joint portion 47, the stretch ratio at which the bent portion of the outer peripheral wall 21 is stretched during blow molding is such that the joint portion 47 is located on the inner peripheral side with respect to the center CL <b> 1 in the thickness direction between the outer peripheral wall 21 and the inner peripheral wall 23. Is compared with the case where the coupling portion 47 is disposed on the outer peripheral side of the center CL1 in the thickness direction between the outer peripheral wall 21 and the inner peripheral wall 23, the thicknesses of the outer peripheral wall 21 and the inner peripheral wall 23 are compared. When the connecting portion 47 is arranged on the outer peripheral side with respect to the direction center CL1, the stretch ratio of the bent portion of the outer peripheral wall 21 is smaller. Therefore, in the vicinity of the coupling portion 47, it is possible to prevent the bent portion of the outer peripheral wall 21 from being stretched at the time of blow molding and reducing the plate thickness.

  (2) In the vicinity of the coupling portion 47, the outer peripheral wall 21 is formed with an outer peripheral wall-side concave portion 33 that is recessed toward the inner peripheral side, and the inner peripheral wall 23 is formed with an inner peripheral wall-side concave portion 41 that is recessed toward the outer peripheral side. The bottom portion 35 of the outer peripheral wall side concave portion 33 and the bottom portion 43 of the inner peripheral wall side concave portion 41 are combined to form a connecting portion 47. The maximum value W1 of the inner peripheral wall side length along the circumferential direction in the inner peripheral wall side concave portion 41 is larger than the maximum value W2 of the outer peripheral wall side length along the circumferential direction of the outer peripheral wall side concave portion 33.

  Even in the inner peripheral wall side recess 41, there is a problem that the bent portion of the inner peripheral wall 23 is stretched at the time of blow molding and the plate thickness is reduced. Here, the maximum value W1 of the inner peripheral wall side length is larger than the maximum value W2 of the outer peripheral wall side length. Therefore, in the inner peripheral wall-side concave portion 41, the stretch ratio at which the bent portion of the inner peripheral wall 23 is stretched during blow molding is reduced, and the plate thickness of the bent portion of the inner peripheral wall 23 is suppressed.

  (3) The inner peripheral wall side recessed part 41 is comprised from the side part 45 extended diagonally, expanding the diameter from the periphery of the bottom part 43 and the bottom part 43 toward the inner peripheral side.

  The side surface portion 45 constituting the inner peripheral wall side recess 41 extends obliquely while increasing in diameter from the peripheral edge of the bottom portion 43 toward the inner peripheral side. Therefore, compared with the case where the diameter is extended from the peripheral edge of the bottom 43 to the inner peripheral side, the stretch ratio at which the bent portion of the inner peripheral wall 23 is stretched during blow molding is further reduced, and the bent portion of the inner peripheral wall 23 is reduced. Thinning of the plate thickness is further suppressed.

  In addition, this invention is not limited to embodiment mentioned above, A various change and deformation | transformation are possible based on the technical idea of this invention.

 For example, the blow molded body is not limited to the case where it has a thickness direction center CL1 that draws a single arc as shown in FIG. 3, but a shape in which different arcs are combined, that is, the upper side of the blow molded body has one dimension. The arc drawn with the radius of the center is the center in the thickness direction, and the arc drawn with another radius that is smoothly continuous with the center of the upper thickness direction where the lower side of the blow molded body is smaller than the one dimension is the center in the thickness direction. Alternatively, only the coupling portion 47 and the vicinity thereof may be arc-shaped with a center CL1 in the thickness direction, and the others may be formed as flat plate-like hollow bodies that are integrally formed as a substantially square shape in a side view. It may be.

  Moreover, although the load absorption member 9 arrange | positioned in the lid 3 of the glove box 1 was described as an example of a blow molded body, this invention is not limited to this, It can apply to various blow molded bodies. .

9 Load absorbing member (blow molded product)
21 outer peripheral wall 23 inner peripheral wall 33 outer peripheral wall side recess 35 bottom (part)
41 Inner peripheral wall side recess 43 Bottom (part)
45 Side part 47 Joint part 49 Hollow part

Claims (3)

In a side view, at least a part is curved in an arc shape, and in the cross section along the circumferential direction curved in this arc shape, the outer peripheral wall arranged on the outer peripheral side and the outer peripheral wall are separated from the inner peripheral side on the inner side in the thickness direction. Is a flat blow-molded body in which a hollow portion is formed between the inner peripheral wall and
A part of the outer peripheral wall and the inner peripheral wall are coupled via a coupling part,
The blow-molded product, wherein the coupling portion is disposed on the outer peripheral side with respect to the center in the thickness direction between the outer peripheral wall and the inner peripheral wall facing the outer peripheral wall. The blow molded article according to claim 1,
In the vicinity of the coupling portion, the outer peripheral wall is formed with an outer peripheral wall-side concave portion that is recessed toward the inner peripheral side, and the inner peripheral wall is formed with an inner peripheral wall-side concave portion that is recessed toward the outer peripheral side. The bottom part of the side concave part and the bottom part of the inner peripheral wall side concave part are combined to constitute the coupling part,
The blow molded article characterized in that the maximum value of the inner peripheral wall side length along the circumferential direction in the inner peripheral wall side concave portion is larger than the maximum value of the outer peripheral wall side length along the circumferential direction of the outer peripheral wall side concave portion. . A blow molded article according to claim 2,
The inner peripheral wall side concave portion is composed of the bottom portion and a side surface portion extending obliquely while increasing in diameter from the periphery of the bottom portion toward the inner peripheral side.

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