JP2008230127A - Resin molded body, molding method of the resin molded body, and air-conditioning air duct with the resin molded body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin molded body with a high insulation effect and highly rigidity. <P>SOLUTION: The resin molded body 1 with a substantially U-shape crosssection is constituted of a pair of plate like side walls 7 facing each other and a plate like bottom wall 9 integrally connecting one-side ends of the side walls 7 and has an opening 11 at an opposite side of the bottom wall 9. A pair of protruding ribs 13 inclined so as to be spaced from each other toward opposite sides of the bottom walls 9 are formed in intersecting parts of the pair of side walls 7 and the bottom wall 9. Skin layers 19 of surfaces part of the pair of side walls 7, the bottom wall 9, and the pair of protruding ribs 13 are formed of solid layers without voids, and an inner part surrounded by the solid layer is formed of porous layers 21 continuous with one another. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a resin molded body, a method for molding the resin molded body, and an air conditioning air duct including the resin molded body.

Patent Document 1 discloses a resin molded product having a cylindrical protrusion and having a plurality of step portions formed on the peripheral wall thereof. Each of the plurality of step portions is formed continuously over the entire circumference of the peripheral wall, and is disposed at intervals in the protruding direction of the cylindrical protruding portion. And while the part between adjacent step parts is formed thin and solid with no gap, each step part is formed with a porous layer and a thick wall to increase the rigidity of the resin molded product. Yes.
JP 2006-199012 A

  By the way, it is known that when a porous layer is provided on a resin molded product, the heat insulation effect is enhanced. However, in the resin molded body of Patent Document 1, only the inside of each step portion is a porous layer, and the porous layer is not continuous over the entire cylindrical protruding portion. Cannot expect a high heat insulating effect on the peripheral wall portion of the cylindrical protrusion.

  This invention is made | formed in view of this point, The place made into the objective is to provide a highly rigid resin molding with a high heat insulation effect.

  The invention of claim 1 is composed of a pair of plate-like side walls facing each other and a plate-like bottom wall integrally connecting one end of the side walls, and has a substantially U-shaped cross section having an open port on the opposite side to the bottom wall. In the resin molded body, a pair of ridge ribs inclined so as to be separated from each other toward the opposite side of the bottom wall is formed at the intersection of the pair of side walls and the bottom wall, The surface layer portions of the pair of side walls, the bottom wall, and the pair of protruding ribs are formed of a solid layer without voids, and the interior surrounded by the solid layer is formed of a continuous porous layer. To do.

  Invention of Claim 2 is the resin molding of Claim 1, Comprising: The flange part extended outside is integrally formed in each edge by the side of the said opening | mouth opening of a pair of said side wall, This flange part Is characterized in that it is entirely formed of the solid layer.

  A third aspect of the present invention is a molding method for molding the resin molded body according to the first aspect using a mold, and the inner surface of each of the bottom wall and the pair of side walls is molded as the mold. A fixed mold having a molding surface; and a molding surface that molds an outer surface of the bottom wall and an opposing surface of the pair of protruding ribs continuous to the outer surface, and a thickness of the bottom wall relative to the fixed mold is A movable mold for the bottom wall that moves in an increasing / decreasing direction, a molding surface that molds the outer surface of each side wall, the outer surface of the rib rib that continues to the outer surface, and the tip surface of the rib rib that follows the outer surface. A pair of side wall movable molds that move in a direction in which the thickness of the side wall increases or decreases with respect to the fixed mold, and the bottom wall movable mold and the side wall movable molds on both sides thereof, The side walls of the movable rib rib tip end surface are mutually inclined by inclined surfaces extending in a substantially V shape. In a state in which the bottom wall movable mold and the side wall movable molds on both sides thereof are brought close to the fixed mold and filled with a thermoplastic molten resin in a slidably contacted manner, A solid layer is formed on the surface layer portion of the pair of side walls, the bottom wall, and the pair of protruding ribs, and before the inner molten resin surrounded by the solid layer is solidified, the pair of movable molds for the side walls, The cavity for molding the side wall is moved in an expanding direction, and the bottom wall movable mold is slid on the sliding surface while following the movement of the side wall movable mold, and separated from the fixed mold. The porous layer is formed inside the pair of side walls, the bottom wall, and the ribs by enlarging a cavity that forms the bottom wall and the pair of ribs.

  The invention of claim 4 is an air conditioning air duct for a vehicle having an air passage for guiding the air-conditioning air supplied from the air conditioner to the air-conditioning air outlet of the instrument panel, wherein at least a part of the air passage is claimed. It was comprised by the resin molding of claim | item 1. It is characterized by the above-mentioned.

  According to the first aspect of the present invention, a porous layer is formed inside the pair of side walls, the bottom wall, and the pair of protruding ribs. That is, the resin molded body has a high heat insulating effect because a continuous porous layer is formed over the entire interior. In addition, since the ribs are formed at the intersections between the pair of side walls and the bottom wall, the resin molded body has high rigidity. For this reason, a resin molding can be effectively utilized as a highly rigid heat insulation member.

  According to the invention of claim 2, since the flange portion is formed, the rigidity of the resin molded body is further increased and the entire flange portion is formed of a solid layer, so that the flange portion is coupled to another member. In this case, the rigidity of the flange portion can be ensured.

  According to the invention of claim 3, by using the protruding ribs that are inclined and protrude so as to be separated from each other, the sliding surfaces inclined in a V-shape are provided, thereby providing the side wall. The movable mold and the movable mold for the bottom wall are slidably contacted. Therefore, even when the movable mold for the bottom wall and the movable mold for the sidewall are moved in the cavity expansion direction in order to form the porous layer, the cavity is always kept in a hermetically sealed state. The resin molded body having a continuous porous layer can be reliably obtained without the resin flowing out.

  According to the invention of claim 4, by configuring at least a part of the air passage by the resin molded body of claim 1, to the conditioned air passing through the resin molded body toward the air-conditioned air outlet, It can suppress that heat loss arises.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view of a resin molded body 1 according to an embodiment of the present invention. The resin molded body 1 includes a main body portion 3 and a flange portion 5.

  The main body 3 includes a pair of opposing plate-like side walls 7, a plate-like bottom wall 9 that integrally connects one end of the side walls 7, and a bottom wall 9 at the intersection of the pair of side walls 7 and the bottom wall 9. It has a pair of protruding ribs 13 formed to be inclined so as to be separated from each other toward the opposite side, and has a substantially U-shaped cross section having an opening 11 on the opposite side to the bottom wall 9. The main body 3 includes a skin layer 19 that forms a surface layer portion of the main body 3, and an internal porous layer 21 surrounded by the skin layer 19.

  The skin layer 19 is formed of a solid layer that is substantially free of voids therein, is dense, has a relatively high rigidity, and is rigid, and has a plate-like side wall 7, a bottom wall 9, and surface ribs 13. It is integrally formed throughout.

  The porous layer 21 has a large number of voids therein, and a porous layer 21 a inside the pair of side walls 7, a porous layer 21 b inside the bottom wall 9, and a porous layer 21 c inside the protruding rib 13 are formed. It is continuously formed integrally.

  The flange portion 5 extends outward at each end edge of the pair of side walls 7 on the opening 11 side. The entire flange portion 5 is formed only from a hard solid layer, and is integrally formed with the skin layer 19.

  Since the resin molded body 1 having the above-described configuration has the porous layers 21a, 21b, and 21c formed over the entire inside thereof, a high heat insulating effect can be expected. Moreover, since the rib rib 13 is formed on the resin molded body 1, the resin molded body 1 has high rigidity. For this reason, the resin molding 1 can be effectively utilized as a highly rigid heat insulating member.

  Moreover, since the flange part 5 is formed in the resin molding 1, the rigidity of the resin molding 1 further increases. Moreover, since the flange part 5 is entirely formed of a hard solid layer, the rigidity of the flange part 5 can be ensured when the flange part 5 is coupled to another member.

  Next, a method for molding the resin molded body 1 will be described with reference to FIG.

  The resin molded body 1 is molded using a molding die 15, and the molding die 15 includes a fixed die 23, a bottom wall movable die 25, and a pair of side wall movable dies 27. .

  The fixed mold 23 includes a base portion 29 and a protruding portion 31 that protrudes downward from the base portion 29. The projecting portion 31 has a molding surface 31 a whose front end surface molds the inner surface 9 a of the bottom wall 9 and a molding surface 31 b whose both side surfaces mold the inner surfaces 7 a of the pair of side walls 7. In addition, the base portion 29 has a recess 33 for forming the flange portion 5 on the base outer periphery of the protruding portion 31.

  The bottom wall movable mold 25 is disposed below the projecting portion 31 and has a molding surface 25a for molding the outer surface 9b of the bottom wall 9 at a position facing the molding surface 31a of the projection 31. 9 has a molding surface 25b for molding the opposing surfaces 13a of the pair of protruding ribs 13 continuous with the outer surface 9b. Further, on both sides of the bottom wall movable mold 25, inclined surfaces 25 c are formed that are inclined in a substantially V shape with respect to the center line Y of the bottom wall movable mold 25.

  The pair of side wall movable dies 27 are arranged on both sides of the protrusion 31 and the bottom wall movable mold 25 so as to sandwich the protrusion 31 and the bottom wall movable mold 25 from the left and right below the base 29. The pair of side wall movable dies 27 includes a molding surface 27 a that forms the lower surface 5 a of the flange portion 5, a molding surface 27 b that faces the molding surface 31 b of the protruding portion 31 and molds the outer surface 7 b of the sidewall 7, and a bottom wall A molding surface 27c that molds the outer surface 13b of the rib rib 13 that faces the molding surface 25b of the movable mold 25 and continues to the outer surface 7b of the side wall 7, and a rib that continues to the outer surface 13b of the rib rib 13 It has a molding surface 27d for molding the tip surface 13c of the rib 13. The molding surface 27d of the sidewall movable mold 27 is formed on a part of the inclined surface 27e extending from the lower end of the molding surface 27c, and the inclined surface 25c of the bottom wall movable mold 25 is the inclined surface 27e. And substantially V-shaped corresponding to the inclined surface 27e.

  Then, as shown in FIG. 2A, the bottom wall movable mold 25 and the side walls on both sides thereof so that the inclined surface 27e of the sidewall movable mold 27 and the inclined surface 25c of the bottom wall movable mold 25 are in contact with each other. The cavity 17 is formed with the movable mold 27 close to the fixed mold 23 and closed. The cavity 17 has a range A between the molding surface 33a that forms the upper surface 5b of the flange portion 5 in the recess 33 and the molding surface 27a of the movable mold 27 for the side wall (hereinafter referred to as the first cavity range A), and the protrusion 31. The molding surface 31b and the molding surface 27b of the movable side wall mold 27 (hereinafter referred to as the second cavity range B), the molding surface 27c of the side wall movable mold 27 and the molding of the bottom wall movable mold 25 are formed. A range C between the surface 25b (hereinafter referred to as a third cavity range C) and a range D between the molding surface 31a of the protruding portion 31 and the molding surface 25a of the bottom wall movable mold 25 (hereinafter referred to as a fourth cavity range C). A cavity portion D), a flange portion 5 is formed by the first cavity range A, a pair of side walls 7 is formed by the second cavity range B, and a rib rib is formed by the third cavity range C. 13 is formed A bottom wall 9 is formed by four cavity ranges D.

  In the state in which the cavity 17 is formed, the pair of side wall movable dies 27 is driven in a direction in which the thickness of the side wall 7 increases or decreases with respect to the fixed die 23 by a driving means (not shown), that is, in the second cavity range B. It is movable in the direction in which the interval increases or decreases (E and F shown in FIG. 2A). The bottom wall movable mold 25 is supported by the sidewall movable mold 27 by the inclined surface 25c being in contact with the inclined surface 27e, and the inclined surface 27e and the inclined surface 25c are slidably in contact with each other. . When the side wall movable mold 27 moves, the inclined surface 25c slides on the inclined surface 27e following the movement, and accordingly, the bottom wall movable mold 25 moves on the center line Y. Move in the vertical direction (J, K shown in the figure). More specifically, when the side wall movable mold 27 is moved in the direction E in which the distance between the second cavity ranges B is reduced, the inclined surface 27e presses the inclined surface 25c. If the side wall movable mold 27 is moved in the direction F in which the interval of the second cavity range B is increased, the bottom wall movable mold 25 is moved downward (by the weight of the bottom wall movable mold 25). Move in the K direction). The molding surface 27d is formed in a range where the inclined surface 25c of the bottom wall movable mold 25 is not in contact with the inclined surface 27e. The bottom wall movable mold 25 may be moved downward by an urging means for urging downward, for example, a spring, without depending on the weight of the bottom wall movable mold 25.

  Next, the molding procedure of the resin molded body 1 will be described based on FIG.

  First, the cavity 17 is formed inside the mold 15 by closing the mold so that the mold 15 is in the state shown in FIG. In this state, the fiber-containing thermoplastic resin heated and melted by an injection machine (not shown) is injected and filled into the cavity 17 from a resin injection port (not shown). By this injection filling, the first, second, third, and fourth cavity ranges A, B, C, and D are filled with the thermoplastic resin without any boundary.

  Thereafter, in the process in which the filled thermoplastic resin containing fiber is cooled and solidified by contact with the mold surface, a solid layer is formed in the vicinity of the molding surfaces of the second, third, and fourth cavity ranges B, C, and D. A skin layer 19 is generated. Then, before the molten resin inside the skin layer 19 is solidified, as shown in FIG. 2B, the pair of side wall movable molds 27 are moved in the direction F in which the interval between the second cavity ranges B is expanded. . As a result, the movable mold 25 for the bottom wall moves downward K, which is the direction in which the inclined surface 25c of the movable mold 25 for the bottom wall slides on the inclined surface 27e of the movable mold 27 for the sidewall, and is away from the fixed mold 23. To do. As a result, the intervals between the second, third, and fourth cavity ranges B, C, and D are expanded. In this case, the amount of movement of the pair of side wall movable molds 27 and bottom wall movable mold 25 is 2 after expansion with respect to the volume of the second, third, and fourth cavity ranges B, C, and D before expansion. Do it so that it becomes double or more. At this time, in the second, third, and fourth cavity ranges B, C, and D, the surface layer portion that has already solidified to form the skin layer 19 does not expand due to the volume expansion. On the other hand, since the inner portion of the skin layer 19 is in a gel state having a high viscosity, the fiber-containing thermoplastic resin that has been compressed in the mold 15 by the expansion of the volume up to now is the protruding portion 31. Then, the fibers in the side wall movable mold 27 and the bottom wall movable mold 25 are pulled and expanded, and the fibers in the compressed thermoplastic resin containing fibers are released from the compression and restored, so-called springback phenomenon. Also, the thermoplastic resin expands. As a result, in the second, third, and fourth cavity ranges B, C, and D, the skin layer 19 made of a solid layer is formed on the surface layer portions of the pair of side walls 7, the bottom wall 9, and the pair of protruding ribs 13. At the same time, a porous layer 21 having a large number of voids is formed inside the skin layer 19. As a result, the main body 3 is obtained.

  Further, when the side wall movable mold 27 and the bottom wall movable mold 25 are moved, the interval of the first cavity range A is not enlarged. Thereby, in the 1st cavity range A which shape | molds the flange part 5, the porous layer 21 is not formed but a solid layer is formed in the whole.

  Thereafter, the resin molded body 1 can be obtained by removing the resin molded body 1 from the mold 15.

  According to the molding method, by utilizing the provision of the protruding ribs 13 protruding so as to be separated from each other, the inclined surfaces inclined in a V-shape are provided, so that the movable mold 27 for the side wall and the bottom The movable mold for wall 25 is slidably contacted. Therefore, even when the movable mold 25 for the bottom wall and the movable mold 27 for the side wall are moved in the direction in which the cavity 17 expands in order to form the porous layer 21, the inside of the cavity 17 is always kept sealed. Therefore, the molten resin does not flow out of the cavity 17 and the resin molded body 1 having the continuous porous layer 21 can be obtained reliably.

  In the molding method, a foamed material may be contained in the fiber-containing thermoplastic resin. By doing so, when the expansion ratio of the cavity 17 is increased to form a thick resin molded body, the foaming force (expansion) of the foam material is increased even if the expansion amount of the thermoplastic resin containing fibers is insufficient. The insufficient expansion amount is supplemented by the pressure), and voids can be reliably formed in the porous layer, which is preferable. In this case, examples of the foam material include a chemical foam material that generates gas by a chemical reaction, and a physical foam material that uses an inert gas such as carbon dioxide gas and nitrogen gas.

  Here, the resin molding 1 can be used as an air passage of an air conditioning air duct provided in the vehicle. Hereinafter, a description will be given with reference to FIGS. 3 and 4.

  FIG. 3 is a perspective view of an instrument panel of a vehicle to which the resin molded body 1 according to the present embodiment is applied, and FIG. 4 is a sectional view taken along line IV-IV in FIG.

  Reference numeral 40 denotes an instrument panel disposed at the front end of the passenger compartment. A defroster outlet 43 that blows air-conditioned air to the inner surface of the front windshield 41 is formed in the vehicle body front side portion of the instrument panel 40. Further, a side vent air outlet 45 and a demister 47 for blowing air-conditioned air to both ends of the vehicle interior, and a center vent air outlet 48 for blowing air-conditioned air to the center of the vehicle interior are provided at the vehicle body rear portion of the instrument panel 40, respectively. Is formed.

  As shown in FIG. 4, an air conditioner 51 is disposed below the instrument panel 40, and conditioned air generated by the air conditioner 51 is sent from the air outlet port 52 to the defroster outlet 43 and the demister. An air-conditioning air duct 49 as the resin molded body 1 having an air passage leading to 47 is provided.

  An inclined portion 46 that is inclined substantially parallel to the front windshield 41 is provided at the vehicle body front side end portion of the instrument panel 40, and the front windshield 41 is bonded to the inclined portion 46 by a sealing material 42. In addition, the defroster outlet 43 is formed in the horizontal portion 50 of the instrument panel 40 located on the rear side of the vehicle body of the inclined portion 46 and in the vicinity thereof.

  In the air-conditioning air duct 49, the flange portion 5 is hermetically joined to the lower surface of the horizontal portion 50 by vibration welding, hot plate welding, high frequency welding, an adhesive or the like so that the opening 11 is located below the defroster outlet 43. . Thereby, since the porous layer 21 is formed in the air-conditioning air duct 49 as the resin molded body 1 and the heat insulating property is high, heat loss is caused in the air-conditioning air flowing through the air-conditioning air duct 49 toward the defroster outlet 43. Occurrence is suppressed.

  Further, since the flange portion 5 is formed only by a hard solid layer, when the flange portion 5 is attached to the instrument panel 40 by welding or the like, the flange portion 5 is not damaged and can be firmly attached.

  In addition, you may make it form the resin molding 1 only in the duct led to the defroster blower outlet 43, for example, without forming over the air conditioning air duct 49 whole.

  Further, the resin molded body 1 may be applied not only to the instrument panel 40 but also as a duct having a closed cross-sectional structure, for example, a duct for guiding air-conditioned air from the front of the vehicle to the rear (rear seat side) of the vehicle. it can. That is, after integrally molding the resin molded body 1 molded in the above embodiment and superposing the flange portions 5 so that the open ports 11 of the pair of resin molded bodies 1 correspond, the flange portions 5 are bonded to each other by welding or the like. The duct having a closed cross-sectional structure can be obtained by joining and integrating.

It is a perspective view of the resin molding in the embodiment of the present invention. It is a figure which shows the shaping | molding procedure of a resin molding. It is a perspective view of the instrument panel of the vehicle in this embodiment. It is the IV-IV sectional view taken on the line of FIG.

Explanation of symbols

1 resin molding,
5 flange part,
7 side walls,
9 Bottom wall,
11 Open mouth,
13 Rib rib,
17 cavities,
19 Skin layer (surface layer part),
21 porous layer,
23 Fixed type,
25 Movable type for bottom wall,
25c, 27e inclined surface,
27 Movable type for side walls,
40 instrument panel,
43 Defroster outlet (air conditioning air outlet),
49 Air-conditioning air duct,
51 air conditioner,
F, K Direction in which the cavity expands.

Claims (4)

A resin molded body having a substantially U-shaped cross section comprising a pair of opposed plate-like side walls and a plate-like bottom wall integrally joining one end of the side walls, and having an opening on the opposite side of the bottom wall,
A pair of ridge ribs that are inclined so as to be separated from each other toward the opposite side of the bottom wall are formed at the intersection of the pair of side walls and the bottom wall,
The surface layer portions of the pair of side walls, the bottom wall, and the pair of protruding ribs are formed of a solid layer without voids, and the interior surrounded by the solid layer is formed of a continuous porous layer. Resin molded body. The resin molded body according to claim 1,
A flange portion extending outward is integrally formed at each edge on the opening side of the pair of side walls,
The resin molded body, wherein the flange portion is entirely formed of the solid layer. A molding method for molding the resin molded body according to claim 1 using a mold,
As the mold,
A fixed mold having a molding surface for molding the inner surface of each of the bottom wall and the pair of side walls;
A bottom wall having a molding surface for molding the outer surface of the bottom wall and the opposed surfaces of the pair of protruding ribs continuous with the outer surface and moving in a direction in which the thickness of the bottom wall increases or decreases with respect to the fixed mold For movable type,
Each having an outer surface of the side wall, an outer surface of the rib rib continuous with the outer surface, and a molding surface for molding a tip surface of the rib rib following the outer surface, A pair of side wall movable molds that move in the direction of increasing or decreasing the plate thickness,
The bottom wall movable mold and the sidewall movable molds on both sides thereof are slidably brought into contact with each other by inclined surfaces extending in a substantially V-shape from the molding surface of the rib rib tip surface of the sidewall movable mold. Let me know
With the bottom wall movable mold and the side wall movable molds on both sides thereof close to the fixed mold and closed, the cavity is filled with a thermoplastic molten resin, whereby the pair of side walls, the bottom wall, and the pair Form a solid layer on the surface layer part of the ribs of
Before the inner molten resin surrounded by the solid layer solidifies, the pair of side wall movable molds are moved in a direction in which the cavity for molding the side walls expands, and the movement of the side wall movable molds is followed. Then, while sliding the bottom wall movable mold on the sliding surface, the bottom wall and the pair of projecting ribs are separated from the fixed mold to enlarge the cavities forming the pair of side walls. Forming the porous layer inside the bottom wall and the ribs. An air conditioning air duct for a vehicle having an air passage that guides air conditioning air supplied from an air conditioner to an air conditioning air outlet of an instrument panel,
An air-conditioning air duct, wherein at least a part of the air passage is constituted by the resin molded body according to claim 1.

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