JP2010030101A - Hollow molding and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the jointing force of a resin-made hollow molding formed by butting and jointing of two split bodies. <P>SOLUTION: In the resin-made hollow molding formed by butting an lower-side body 2 against an upper-side body and jointing together, the lower-side body 2 and the upper-side body have ribs 15 forming a plurality of closed cross-sections within them, and the ribs 15 are butted mutually. The lower-side body 2 and the upper-side body are jointed through a jointed body 4 consisting of an enveloping portion 41 arranged along the outer periphery of the butt surface 5 between the lower-side body 2 and the upper-side body and a core portion 43 penetrating the butt surface 17 of the ribs 15 and embedded in the ribs 15 of the lower-side body 2 and the upper-side body, connected with each other. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a resin hollow molded article and a method for producing the same.

Conventionally, as a method for producing a resin-made hollow molded article, first, a divided body divided into two parts is molded, and then these divided bodies are butted against each other and set in a hollow form, A method is known in which a resin is injected along the butting surface of the divided body to form a joined body in a headband shape, and both divided bodies are joined via this joined body (for example, Patent Document 1). reference).
Japanese Patent Publication No. 2-38377

The hollow molded article having the above-described structure has no problem when external force is hardly applied or is extremely small even when applied.
However, various problems arise when used in a form in which a large external force is applied to the hollow molded article. For example, when a large external force is applied to the hollow molded article, stress may be applied to the joined body to cause deformation or breakage, or the joined body may be separated from the divided body and come off.
Therefore, the present invention provides a hollow molded article that is firmly bonded and a method for manufacturing the same.

In the hollow molded article and the manufacturing method thereof according to the present invention, the following means are adopted in order to solve the above problems.
The invention according to claim 1 is a resin-made hollow molded product (for example, in an embodiment described later) formed by abutting and joining two divided bodies (for example, a lower body 2 and an upper body 3 in the embodiment described later). In the hollow molded article 1), an enclosure (for example, an embodiment to be described later) disposed along the outer periphery of the butting surface (for example, the butting surfaces 5, 6, 17, and 18 in the embodiments described later) of the two divided bodies. And a core portion (for example, the core portion 43 and the second core portion 46 in the embodiments described later) penetrating the butted surfaces and immersing in the meat portions of the two divided bodies. The hollow molded article is characterized in that the two divided bodies are joined by a joined body (for example, a joined body 4 in an embodiment described later).

  The invention according to a second aspect is the invention according to the first aspect, wherein the two divided bodies have ribs that form a plurality of closed sections inside (for example, the ribs 15, 16, 27, 28, and the like in the embodiments described later). 29), the ribs are also abutted against each other, and the core portion penetrates the abutting surface of the ribs and is immersed in the rib portions of both divided bodies.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, a part of the core portion of the joined body extends to the outer surface of the divided body and is exposed.

  According to a fourth aspect of the present invention, in the invention according to the third aspect, the joined body is characterized in that a part of the core portion protrudes from the outer surface of the divided body.

  The invention according to claim 5 is a groove (for example, the groove 19, in the embodiment described later) that opens to the butting surface (for example, the butting surfaces 5, 6, 17, 18 in the embodiment described later) and part of the groove continues to the outer peripheral surface. 20) having a pair of divided bodies (for example, the lower main body 2 and the upper main body 3 in the embodiments described later) are previously formed of a resin, and the pair of divided bodies are formed as molds (for example, a mold in the embodiments described later). 81, 82), butting each other at the butting surfaces, forming cavities (for example, cavities 83 in the embodiments described later) along the outer periphery of the butting surfaces, and clamping the mold, and pouring the molten resin into the cavities A method for producing a hollow molded product comprising filling the cavity and the groove with a molten resin and solidifying the molten resin to join the pair of divided bodies It is.

  According to the invention of claim 1, the two divided bodies are joined by the surrounding portion that joins the outer peripheral surfaces of the divided bodies and the core portion that immerses in the meat part of the two divided bodies. Becomes extremely large, and as a result, the bonding strength becomes extremely large. In addition, since the cross-sectional area of the joined body also increases and the strength of the joined body increases, even when an external force is applied to the hollow molded product and a large stress is applied to the joined body, deformation and breakage of the joined body can be prevented. . Further, since the bonding strength is high and the strength of the bonded body is also large, the bonded body is not separated from the divided body.

  According to the invention which concerns on Claim 2, since the ribs of a division body do not raise | generate a position shift and it connects in the state which the ribs faced reliably, the mechanical strength of a hollow molded article improves.

  According to the invention of claim 3, it can be confirmed that a part of the joined body is definitely immersed in the divided body.

  According to the invention which concerns on Claim 4, a part of core part which protrudes from the outer surface of a division surface can be utilized, for example as a positioning pin, a fixing pin, etc. of components to attach later.

  According to the invention which concerns on Claim 5, it becomes possible to manufacture the hollow molded product described in Claim 1 easily.

Embodiments of a hollow molded article and a manufacturing method thereof according to the present invention will be described below with reference to the drawings of FIGS.
<Example 1>
First, Embodiment 1 of a hollow molded article and a manufacturing method thereof according to the present invention will be described with reference to the drawings of FIGS.
As shown in FIG. 1, the hollow molded product 1 has an elongated rectangular parallelepiped shape in which all six surfaces are closed, and a lower main body (divided body) 2 disposed on the lower side and an upper main body (divided body) disposed on the upper side. ) 3 and a joined body 4 that joins the lower main body 2 and the upper main body 3 to each other. The lower main body 2, the upper main body 3, and the joined body 4 are all formed of the same high-strength resin (for example, a polyamide resin containing glass fibers or a polyamide resin containing carbon fibers).

  The lower main body 2 and the upper main body 3 have the same shape and the same dimensions. As shown in FIGS. 2 to 4, the lower main body 2 and the upper main body 3 have a box shape in which the opposite sides are opened, and the opening sides are opposite to each other. The abutting surface 5 of the lower body 2 and the abutting surface 6 of the upper body 3 are provided so as to go around the center in the height direction of the hollow molded product 1. FIG. 2 is a perspective view partially showing a state in which the upper body 3 is removed from the hollow molded article 1.

  On the outer surfaces 7 and 8 of the lower main body 2 and the upper main body 3, rectangular concave portions 9 and 10 connected to the outer peripheral edges of the butting surfaces 5 and 6 are provided so as to go around the center in the height direction of the hollow molded product 1. It has been. In addition, a rectangular recess 12 that surrounds the outer surface 7 and the lower surface 11 of the lower main body 2 is formed at approximately the center in the longitudinal direction of the lower main body 2, and continues to the recess 9 of the outer surface 7. Similarly, the upper body 3 is also formed with a rectangular recess 14 around the outer surface 8 and the upper surface 13 of the upper body 3 at the same position in the longitudinal direction, and is continuous with the recess 10 on the outer surface 8.

In addition, a plurality of plate-like ribs 15 extending in the width direction perpendicular to the outer surface 7 are provided in the lower main body 2 at equal intervals in the longitudinal direction. A closed cross section is formed. The upper body 3 is also provided with a plurality of plate-like ribs 16 extending in the width direction perpendicular to the outer surface 8 at equal intervals in the longitudinal direction, and the ribs 16 form a plurality of closed sections in the upper body 3. . The rib 15 of the lower main body 2 and the rib 16 of the upper main body 3 are also abutted at the center in the height direction of the hollow molded product 1.
Grooves 19 and 20 are formed in the rib 15 and the rib 16 so as to open to the respective abutting surfaces 17 and 18. The grooves 19 and 20 are formed over the entire width and height of the respective ribs 15 and 16.

As shown in FIG. 5, the groove 19 provided in the rib 15 of the lower main body 2 is connected to the recess 9 provided in the outer surface 7 by a groove 21 continuous to the outer surface 7 of the lower main body 2. Similarly, the groove 20 provided in the rib 16 of the upper main body 3 is connected to the recess 10 provided in the outer surface 8 by the groove 22 continuous to the outer surface 8 of the upper main body 3.
Further, as shown in FIG. 5, the lower body 2 is provided with cylindrical holes 23, 23 penetrating from the left and right ends of the grooves 19 to the lower surface 11, and the upper body 3 is provided with the grooves 20. Cylindrical holes 24, 24 penetrating from the left and right ends to the upper surface 13 are provided.

  The joined body 4 includes recesses 9 and 12 provided in the lower body 2, grooves 19 and 21, holes 23, recesses 10 and 14 provided in the upper body 3, grooves 20 and 22, and holes 24. It is provided so as to fill all. The joined body 4 includes an enclosure 41 disposed along the outer periphery of the abutting surface of the lower body 2 and the upper body 3, and outer surfaces of the lower body 2 and the upper body 3 so as to intersect the enclosure 41. An intermediate ring portion 42 that circulates around the core body 43, a core portion 43 that penetrates the butted surfaces 17 and 18 of the ribs 15 and 16 of the lower body 2 and the upper body 3, and is immersed in the meat portions of the ribs 15 and 16; A connecting portion 44 that connects the core portion 43, and a portion of the core portion 43 serves as a pin 45 that extends to the lower surface 11 of the lower body 2 and the upper surface 13 of the upper body 3. It is exposed as one. The surrounding portion 41 is formed flush with the outer surfaces of the lower main body 2 and the upper main body 3.

Next, the manufacturing method of the hollow molded article comprised in this way is demonstrated with reference to FIG.
First, the lower main body 2 and the upper main body 3 having the above-described shape are made of high-strength resin by injection molding or the like. In this embodiment, since the lower main body 2 and the upper main body 3 have the same shape and the same dimensions, two molded products manufactured using the same mold are prepared, and one is used as the lower main body 2. One can be used as the upper body 3.

  Next, as shown in FIG. 6, the lower main body 2 and the upper main body 3 are set in the molds 81 and 82, and the molds are clamped. At that time, the lower main body 2 and the upper main body 3 are made to face each other on the opening side, the butting surfaces 5 and 17 of the lower main body 2 and the butting surfaces 6 and 18 of the upper main body 3 are butted, and the lower main body 2 The outer surface of the upper body 3 is brought into close contact with the inner surface of the lower mold 81, and the outer surface of the upper body 3 is brought into close contact with the inner surface of the upper mold 82. , 14 and dies 81, 82 are formed with cavities 83. Thereby, the cavity 83 is formed along the outer periphery of the butting surfaces 5 and 6.

The cavity 83 communicates with the groove 21 of the lower main body 2, further communicates with the groove 19 via the groove 21, and further communicates with the hole 23 via the groove 19. Similarly, the cavity 83 communicates with the groove 22 of the upper body 3, further communicates with the groove 20 via the groove 22, and further communicates with the hole 24 via the groove 20.
A plurality of gates 84 connected to the cavity 83 are provided at appropriate positions in the upper die 82, and each gate 84 communicates with a main spool 87 provided on the fixed die 86 via a sub spool 85.
Although not shown, each hole 23 of the lower main body 2 and each hole 24 of the upper main body 3 communicate with gas vent passages provided in the molds 81 and 82.

  Next, a molten resin of high strength resin is injected into the main spool 87 of the fixed mold 86 and injected from the gate 84 into the cavity 83. The molten resin injected into the cavity 83 flows from the cavity 83 through the groove 21 of the lower main body 2 and the groove 22 of the upper main body 3 into the groove 19 of the lower main body 2 and the groove 20 of the upper main body 3. It flows into the hole 23 of the side body 2 and the hole 24 of the upper body 3. The molten resin flows into the cavity 83, the grooves 19 and 21 of the lower body 2, the holes 23 of the lower body 2, the grooves 20 and 22 of the upper body 3, and the holes 24 of the upper body 3 without any gaps.

When the molten resin is solidified in this state, the surrounding portion 41 and the intermediate ring portion 42 of the joined body 4 are formed by the resin solidified in the cavity 83, and the grooves of the ribs 15 and 16 of the lower body 2 and the upper body 3 are formed. The core part 43 of the joined body 4 is formed by the resin solidified in 19, 20 and the pin 45 of the joined body 4 is formed by the resin solidified in the hole 23 of the lower main body 2 and the hole 24 of the upper main body 3, The connecting portion 44 of the joined body 4 is formed by the resin solidified in the groove 21 of the lower main body 2 and the groove 22 of the upper main body 3.
The lower body 2 and the upper body 3 are joined by the joined body 4 and are integrally connected.

  According to the hollow molded article thus configured, the lower main body 2 and the upper main body 3 include the surrounding portion 42 of the joined body 4 that joins the outer peripheral portions of the butted surfaces 5 and 6, the lower main body 2, and the upper main body 3. Since it joins with the core part 43 of the joined body 4 immersed in the meat | flesh part of the ribs 15 and 16 of the main body 3, a joining area becomes very large and, as a result, joining strength becomes very large. In addition, since the cross-sectional area of the joined body 4 is increased and the strength of the joined body 4 is increased, even if a large stress is applied to the joined body 4 due to an external force applied to the hollow molded article 1, the deformation of the joined body 4, Breakage can be prevented. Further, since the bonding strength is high and the strength of the bonded body 4 is also large, the bonded body 4 is not separated from the lower body 2 and the upper body 3.

  Further, in this embodiment, the core portion 43 of the joined body 4 is immersed in the meat portions of the ribs 15 and 16 of the lower main body 2 and the upper main body 3, and the ribs 15 and 16 are integrally joined. The ribs 15 of the main body 2 and the ribs 16 of the upper main body 3 are not displaced, and the ribs 15 and 16 can always reliably hold the butted state at the correct position. As a result, the ribs 15 and 16 can sufficiently exhibit the reinforcing ability, and can sufficiently withstand even when a large external force is applied to the hollow molded article 1, and the strength of the hollow molded article 1 is increased.

  Here, it compares with the case where there is no core part 43 which joins the rib 15 of the lower main body 2, and the rib 16 of the upper main body 3. FIG. If the core part 43 is not provided, the positions of the ribs 15 and 16 may be shifted in the manufacturing stage of the hollow molded article 1, and the positions of the ribs 15 and 16 may be shifted when an external force is applied. If the positions of the ribs 15 and 16 are shifted as described above, the mechanical strength of the ribs 15 and 16 is lowered, and the reinforcing ability is lowered. According to the hollow molded product 1 of the embodiment, this can be prevented, so that the strength of the hollow molded product 1 can be increased.

  In addition, the mechanical strength of the hollow molded article 1 can be increased without increasing the thickness of the lower main body 2 and the upper main body 3. Further, the weight can be reduced as compared with the case where the thickness is increased in order to obtain the same mechanical strength, the capacity of the resin can be reduced, and the cost can be reduced.

  Further, by looking at the holes 23 and 24 on the lower surface 11 and the upper surface 13 of the manufactured hollow molded article 1, it can be confirmed that the tip of the pin 45 extends to the surface. Thereby, it can confirm that the molten resin which is the raw material of the joined body 4 was inject | poured to the termination | terminus at the time of manufacture, and can confirm that the core part 43 was formed reliably.

Next, another embodiment of the hollow molded article 1 will be described with reference to FIGS.
<Example 2>
As shown in FIG. 7, all or part of the pins 45 of the joined body 4 may protrude from the surface (lower surface 11 or upper surface 13) of the lower body 2 or the upper body 3. If it does in this way, it can utilize as a positioning pin at the time of attaching another component to hollow molding 1 or a pin for fixation.

<Example 3>
In the first embodiment described above, the surrounding portion 41 of the joined body 4 is immersed in the lower main body 2 and the upper main body 3, and the outer surface of the surrounding portion 41 is flush with the side surfaces 7 and 8 of the lower main body 2 and the upper main body 3. Although formed, as shown in FIGS. 8 and 9, convex portions 25 and 26 are provided on the outer end side of the abutting surfaces 5 and 6 of the lower main body 2 and the upper main body 3, and the convex portions 25 and 26 are sandwiched therebetween. Thus, it is also possible to form the surrounding portion 41 in a U-shaped cross section. In this case, the surrounding portion 41 of the joined body 4 has a form protruding from the side surfaces 7 and 8 of the lower body 2 and the upper body 3.

<Example 4>
In the first embodiment described above, the ribs 15 and 16 are formed in a flat plate shape, the ribs 15 are provided so as to be orthogonal to the side surfaces 7 and 7 of the lower body 2, and are orthogonal to the side surfaces 8 and 8 of the upper body 3. The ribs 16 are provided, and the ribs 15 and 16 are provided one by one at equal intervals in the longitudinal direction of the lower main body 2 and the upper main body 3, but the shape, number, installation position, etc. of the ribs are not limited thereto. The shape, number, and installation position of the ribs can be set as appropriate according to the difference in stress predicted depending on the shape, required strength, and usage pattern of the hollow molded product 1. In particular, the shape and arrangement of the ribs can be changed in any way as long as the die can be removed in the manufacturing stage of the lower body 2 and the upper body 3.
For example, as shown in FIG. 10, a plurality of ribs 27 are densely provided at a place where a large stress is expected to be applied, and the ribs 27 are provided roughly at a place where a relatively small stress is expected to be applied. May be. Even in this case, the core portion 43 of the joined body 4 is immersed in all the ribs 27.

<Example 5>
Moreover, as shown in FIG. 11, you may provide the rib 28 in the corrugated plate shape which connects the side surfaces 7 and 7 (and between the side surfaces 8 and 8 of the upper side main body 3) of the lower side main body 2. As shown in FIG. In this case, the core portion 43 of the joined body 4 is also formed in a corrugated plate shape and is immersed in the rib 28.

<Example 6>
Or as shown in FIG. 12, you may provide the rib 29 in planar view S shape which connects between the side surfaces 7 and 7 of the lower main body 2 (and between the side surfaces 8 and 8 of the upper main body 3). In this case, the core portion 43 of the joined body 4 is also formed in an S shape in plan view and is immersed in the rib 29.

<Example 7>
Further, as shown in FIGS. 13 and 14, the joined body 4 is immersed in the flesh of the side wall 30 of the lower main body 2 and the side wall 31 of the upper main body 3, and the tip is located near the bottom of the side walls 30 and 31. It is also possible to provide the second core portion 46. The second core portion 46 penetrates the butted surfaces 5 and 6 of the lower main body 2 and the upper main body 3 and is immersed in the meat portions of the side wall 30 of the lower main body 2 and the side wall 31 of the upper main body 3.

  Further, although not shown, the ribs 15 and 16 are not provided on the lower body 2 and the upper body 3, the core portion 43 is not provided on the joined body 4, and the second core portion 46 is provided on the joined body 4. The hollow core 1 can also be configured by immersing the second core portion 46 into the meat portions of the side wall 30 of the lower main body 2 and the side wall 31 of the upper main body 3. This is because the dimension between the side walls 30 and 30 of the lower main body 2 (and the side walls 31 and 31 of the upper main body 3) is short, and there is not enough space to provide ribs between the side walls 30 and 30 (and the side walls 31 and 31). This is effective in the case, and there is an effect that the strength of the hollow molded article 1 can be increased without a rib.

<Other embodiments>
The cross-sectional shape of the hollow molded product 1 is not limited to the rectangular cross-section as in each of the above-described embodiments, and various cross-sectional shapes such as a circle, an ellipse, and a polygon are possible. The cross-sectional shape of the main body 3 may not be symmetrical.
The external shape of the hollow molded article 1 is not limited to the rectangular parallelepiped shape of each of the above-described embodiments, and various external shapes such as a T shape and a Y shape in plan view are possible.
In the hollow molded product 1 of each of the above-described embodiments, the end portion (end portion in the longitudinal direction) is closed, but a pipe-like form having an open end portion is also possible.

In the hollow molded article 1 of each example described above, the lower main body 2, the upper main body 3, and the joined body 4 are formed of the same resin (high strength resin). However, they are not necessarily formed of the same resin. For example, the joined body 4 may be formed of a high-strength resin, and the lower main body 2 and the upper main body 3 may be formed of a resin containing no glass fiber or carbon fiber, or vice versa.
Moreover, the tip of the pin 45 of the joined body 4 is confirmed from the surface of the lower body 2 and the upper body 3 by making the resin of the joined body 4 different from the resin of the lower body 2 and the upper body 3. It can also be made easier. Thereby, it can be easily confirmed that the molten resin, which is the raw material of the bonded body 4, has been injected to the end during manufacture.

It is an external appearance perspective view in Example 1 of the hollow molded article which concerns on this invention. It is a perspective view which shows the state which removed the upper main body in the hollow molded product of Example 1 partially. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is CC sectional drawing of FIG. It is a figure explaining the manufacturing method of the hollow molded product of the said Example 1. FIG. It is a perspective view of the principal part in Example 2 of the hollow molded article which concerns on this invention. It is a perspective view of the principal part in Example 3 of the hollow molded article which concerns on this invention. It is sectional drawing of the hollow molded product of the said Example 3, and is a figure corresponding to FIG. It is a perspective view corresponding to FIG. 2 in Example 4 of the hollow molded article which concerns on this invention. It is a perspective view corresponding to FIG. 2 in Example 5 of the hollow molded article which concerns on this invention. It is a perspective view corresponding to FIG. 2 in Example 6 of the hollow molded article which concerns on this invention. It is a perspective view corresponding to FIG. 2 in Example 7 of the hollow molded article which concerns on this invention. It is sectional drawing of the hollow molded product of the said Example 7, and is a figure corresponding to FIG.

Explanation of symbols

1 Hollow molded product 2 Lower body (split body)
3 Upper body (divided body)
4 Joints 5 and 6 Abutting surfaces 15 and 16 Ribs 17 and 18 Abutting surfaces 19 and 20 Groove 41 Enclosing portion 43 Core portion 45 Pin 46 Second core portion 81 and 82 Mold 83 Cavity

Claims (5)

In a resin-made hollow molded product formed by joining and joining two divided bodies,
By the joined body formed by connecting the surrounding portion arranged along the outer periphery of the butted surfaces of the two divided bodies and the core portion penetrating the butted surfaces and immersing in the meat portion of the two divided bodies, A hollow molded article characterized in that two divided bodies are joined.   The two divided bodies are provided with ribs forming a plurality of closed cross sections inside, and the ribs are also abutted with each other, and the core portion penetrates the abutting surfaces of the ribs and is immersed in the meat portions of the ribs of both the divided bodies. The hollow molded article according to claim 1, wherein the hollow molded article is formed.   3. The hollow molded article according to claim 1, wherein a part of the core portion of the joined body extends to the outer surface of the divided body and is exposed.   The hollow molded article according to claim 3, wherein a part of the core portion of the joined body projects from the outer surface of the divided body. A pair of divided bodies having a groove that is open to the butting surface and a part of which is continuous with the outer peripheral surface is formed in advance with resin
The pair of divided bodies are set in a mold, butted against each other at the butting surface, a cavity is formed along the outer periphery of the butting surface, and the mold is clamped,
A hollow molded article characterized in that a molten resin is poured into the cavity to fill the groove and the groove of the divided body with the molten resin, and the pair of divided bodies are joined by solidifying the molten resin. Production method.

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