JP2008273020A - Cavity filling material and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a cavity filling material capable of improving productivity and surely closing a cavity. <P>SOLUTION: A foaming body 2 foamed and cured by heating is formed into a sheet-like shape, and a foil body 4 is piled up on at least one face of the foaming body 2, and engaging parts 6 which project the foil body 4 to the foaming body 2 side and bite into the foaming body 2 are formed on the foil body 4. The foil body 4 is formed with a raw material which is not softened at a temperature lower than a foaming and curing temperature of the foaming body 2, and for example, a metal foil body is preferable. The engaging part 6 is formed into a hook-type shape, but a bottomed cylindrical shape may be used. In addition, for the cavity filling material 1, a sheet-like foaming body 2 is extrusion-molded and the foil body 4 is piled up on the foaming body 2, and after the engaging parts 6 which is prepared by projecting the foil body 4 to the foaming body 2 side and bites into the foaming body 2 is formed on the foil body 4, it is formed by punching it in accordance with the shape of the cavity. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a void filler that expands and fills voids such as automobile pillars by heating.

  2. Description of the Related Art Conventionally, a technique for improving sound insulation / vibration suppression characteristics and strength by filling an internal space of an automobile pillar or the like by expansion of a void filler has been widely used. This void filler is attached before a hollow body such as a center pillar is assembled. The internal space such as the center pillar is filled with the expanded space filler, and suitable sound insulation / vibration control characteristics and strength can be obtained.

  In order to fill the gap filler without gaps, it is necessary to form the gap filler in a shape corresponding to the gap, and therefore, by injecting a foam material into the cavity formed in the mold, etc. A void filler was formed. If the void filler is formed with a mold corresponding to the shape of each void, various molds must be prepared, and the manufacturing becomes complicated and the productivity cannot be improved.

Therefore, in order to improve productivity, etc., as disclosed in Patent Document 1, the foam is extruded into a sheet shape, and a support such as a metal plate is laminated on the sheet-like foam, The one formed in a shape corresponding to is proposed.
JP 2004-255863 A

  However, in such a conventional product, when the foam is heated to about 120 ° C. to 200 ° C., the foam is once softened and becomes fluid, and then foams when the foam reaches the reaction start temperature. It hardens while closing the gap.

  When the foam is heated and has fluidity, the adhesive force between the foam and the support is reduced, the foam is displaced from the support and hangs down, and there is a problem that the gap may not be sufficiently closed. there were. In addition, if the foam and the support are bonded with an adhesive or a pressure-sensitive adhesive, it is possible to suppress the foam from deviating from the support to some extent, but the adhesive and the pressure-sensitive adhesive are also softened at the heating temperature. There was a problem that a sufficient adhesive force could not be obtained, the foam was displaced from the support, and the voids could not be sufficiently closed.

  An object of the present invention is to provide a void filler and a method for manufacturing the same that can improve productivity and can reliably block voids.

In order to achieve this problem, the present invention has taken the following measures in order to solve the problem. That is,
In the gap filler that expands by heating and fills the gap,
A foam body that is foam-cured by heating is formed into a sheet shape, and a foil body is overlaid on at least one surface of the foam body, and an engaging portion that protrudes toward the foam body and bites into the foam body is provided in the foil body. It is a void filler characterized in that it is formed.

  The foil body may be formed of a material that does not soften at a temperature lower than the temperature at which the foam is foam-cured. At that time, the material of the foil body may be a metal foil body. The engaging portion may have a bowl shape. Alternatively, the engaging portion may have a bottomed cylindrical shape.

Also, an extrusion process for extruding a sheet-like foam that is foam-cured by heating,
A laminating step of superimposing a foil on the foam;
Forming the foil body with an engaging portion that protrudes into the foam body and bites into the foam body; and
Punching process according to the shape of the gap,
This is a method for producing a void filler characterized by comprising:

  The gap filling material of the present invention is a sheet-like foam that is overlapped with a foil body, and the engagement portion formed on the foil body suppresses the flow of the foam when heated, thereby improving productivity. In addition, the voids can be reliably closed. Further, by forming the foil body from a material that does not soften at a temperature lower than the temperature at which the foam is foam-cured, the fluidity of the foam can be reliably suppressed. Is easy to form.

  According to the method for producing a void filler of the present invention, productivity can be improved by extruding a foam, overlaying a foil on the foam, and forming an engagement portion on the foil. .

The best mode for carrying out the present invention will be described below in detail with reference to the drawings.
As shown in FIG. 1, 1 is a gap filler, and the gap filler 1 is formed by superposing a foil body 4 on one side of a sheet-like foam 2 that is foam-cured and cured by heating.

  The foam 2 is blended by appropriately selecting and blending a foaming agent and a curing agent into a resin-based material or a rubber material containing a thermoplastic elastomer, or a material obtained by mixing these materials, and blending other materials as necessary. Forming.

  Examples of the resin-based material include polyethylene (PE), polypropylene (PP), polystyrene (PS), ABS resin, methyl methacrylate resin (PMMA), ethylene / propylene / diene copolymer (EPDM) and other olefin resins, ethylene There are ethylene resins such as vinyl acetate (EVA) or ethylene methyl acrylate (EMMA), styrene resins such as styrene / butadiene block copolymer (SBS), and epoxy resins.

  Examples of rubber materials include natural rubber (NR), polyisoprene rubber (IR), styrene / butadiene rubber (SBR), polybutadiene rubber (BR), acrylonitrile / butadiene rubber (NBR), butyl rubber (IIR), and urethane rubber. (U) etc.

  The curing agent includes an inorganic type and an organic type. Examples of the inorganic type include metal oxides such as sulfur, zinc oxide and magnesium oxide, and examples of the organic type include 4,4′-dithiodimorphone. Examples include phosphorus, thyllium polysulfides such as tetramethylthiuram disulfide (TMTD), peroxides such as dicumyl peroxide (DCP), quinonedioximes such as P-quinonedioxime, and amine compounds such as triethylenetetramine. In addition, inorganic and organic curing agents may be used, aliphatic amines such as ethylenediamine (EDA), aromatic amines such as metaphenylenediamine (MPDA), aromatic acid anhydrides such as phthalic anhydride (PA), etc. The curing agent may be used.

  There are inorganic and organic foaming agents. Examples of the inorganic type include sodium carbonate. Examples of the organic type include azo compounds such as azodicarbonamide (ADCA), N, N′-dinitrosopentamethylene. There are nitroso compounds such as tetramine (DPT), hydrazine derivatives such as 4,4′-oxybisbenzenesulfonyl hydrazide (OBSH), and azide compounds such as P-toluenesulfonyl azide.

  Other additives include foaming aids such as urea, fillers such as calcium carbonate, clay and mica, curing accelerators such as aldehyde amines, guanidines, thiazoles and thiurams, aromatic amines and phosphorus. Examples include aging inhibitors such as acids (antioxidants), oils having paraffin groups, naphthene groups, aroma groups, and the like.

  The material of the foil body 4 may be, for example, a metal foil body such as steel or aluminum, or a film or glass cloth, and is lower than a temperature at which the foam body 2 is foam-cured by heating (for example, 120 ° C. to 200 ° C.). Materials that do not soften at temperature are preferred. Moreover, the thickness of the foil body 4 may be about 0.05 to 0.3 mm, for example, and when the foam body 2 is softened by heating, it is not necessary to have a thickness that can support the foam body 2. When the thickness of the foil body 4 is smaller than 0.05 mm, it becomes difficult to function as the flow resistance of the foam body 2, and when the thickness of the foil body 4 is larger than 0.3 mm, an extrusion tool 8 described later is used. When pressed, the foam body 2 is crushed and the foil body 4 is not pushed out so as to bite into the foam body 2.

  The foil body 4 is superposed on almost the entire surface of one side of the foam 2, and in the present embodiment, the foil body 4 is bonded by the adhesiveness of the foam 2 without using an adhesive or the like. In addition, a plurality of engaging portions 6 that protrude the foil body 4 toward the foam body 2 and bite into the foam body 2 are formed.

  In this embodiment, an aluminum foil body having a thickness of 0.05 mm is used as the material of the foil body 4, and as shown in FIG. 2, in the state where the foam body 2 and the foil body 4 are overlapped, The pushing portion 8 is pressed from the foil body 4 side toward the foam body 2 to form the engaging portion 6. The extruding tool 8 is pressed until it bites into the foam 2, and by pressing the extruding tool 8, a hole 10 is opened in the foil body 4, and a part of the foil body 4 is folded into the foam body 2 and engaged. Part 6 is formed. The front end of the engaging portion 6 is bent into a saddle-shaped cross-sectional shape.

  When the engaging portion 6 is formed in a state where the foam 2 and the foil body 4 are overlapped, if the thickness of the foil body 4 is larger than necessary, when the pusher 8 is pressed, the foam 2 The foil body 4 is not squeezed and extruded so as to bite into the foam body 2. What is necessary is just to determine suitably the thickness of the foil body 4 by experiment etc. so that the engaging part 6 can be formed with the extrusion tool 8. FIG. At that time, the foam 2 is preferably in a moderately softened state, and for example, a state immediately after the foam 2 is extruded from an extruder 12 described later is preferable.

  In forming the engaging portion 6, it is desirable to push the pushing tool 8 at an angle from the oblique direction with respect to the foil body 4, so that the engaging portion 6 is appropriately bitten into the foam 2. Will be able to. The engaging portion 6 is formed so as to bite into the foam 2 at least.

Next, the manufacturing process of the gap filler according to the present embodiment will be described with reference to FIG.
In the extrusion process, a foaming agent and a curing agent are appropriately selected and blended with the above-described resin-based material, rubber material, or a mixed material, and the foam 2 is extruded into a continuous sheet by the extruder 12. . The extruder 12 is kneaded at a temperature of 120 ° C. or less to extrude the foam 2.

  In the laminating step, the foil body 4 described above is superimposed on almost the entire surface of one side of the sheet-like foam 2. For example, the foil body 4 may be formed by stacking the foil body 4 wound around a roll on the sheet-like foam body 2 and bonding the foil body 4 due to the adhesiveness of the foam body 2. The foam 2 immediately after being extruded from the extruder 12 is in a warm state, and the surface has adhesiveness.

  Next, in the forming step, the pushing tool 8 is pushed into the foam 2 from the foil body 4 side to form the engaging portion 6. The foam 2 immediately after being extruded from the extruder 12 is in a warm and moderately soft state, and when the pusher 8 is pushed in, the foil body 4 bites into the foam 2 and the engaging portion 6 is formed. . In the punching step, the void filler 1 having a shape corresponding to the void to be used is punched to form the void filler 1.

Then, the usage method of the space | gap filler 1 formed in this way is demonstrated.
Prior to use, a fixture 21 is attached to the gap filler 1. For example, as shown in FIGS. 9 to 11, the fixture 21 includes a locking portion 22 and a connecting portion 24, and the locking portion 22 has an elastic piece 26 formed at the tip thereof. When the locking portion 22 is inserted into the hole, the elastic piece portion 26 is inserted into the hole while being closed, and when the elastic piece portion 26 passes through the hole, the elastic piece portion 26 opens so that the locking portion 22 does not fall out of the hole. The connecting portion 24 to be locked is erected from the locking portion 22 in a plate shape and has a hook portion 27. The hook portion 27 is inserted into a hole (not shown) formed in the gap filler 1. Thus, the gap filler 1 is fixed to the connecting portion 24.

  The fixing tool 28 shown in FIGS. 12 and 13 is not limited to the fixing tool 21 described above, and the fixing tool 28 includes the locking portion 22 and the elastic piece portion 26 similar to those described above, and the gap filler 1. The protrusion 29b that protrudes into the slit 29a enters a hole (not shown) formed in the gap filler 1 and supports the gap filler 1.

  As shown in FIG. 4A, when the gap filler 1 of the present embodiment is used for the rail 30 of the automobile, the locking portion 22 is inserted into the hole of the inner panel 31 to fix the gap filler 1 to the fixture 21. Temporarily fix with. Then, the outer panel 32 is overlapped with the inner panel 31 to form the rail 30 having the gap 34.

  The gap filler 1 is formed in a shape corresponding to the gap 34 by the aforementioned punching process. For example, the gap is formed to be slightly smaller than the cross-sectional shape of the closed gap 34 so that a gap of about 1 mm is formed from the inner walls of the inner panel 31 and the outer panel 32.

  Moreover, when attaching, it attaches so that the space | gap filler 1 may be in the state standing substantially in the space | gap 34 so that the surface of the foam 2 and a gravitational direction may become substantially parallel. Furthermore, it arrange | positions so that the engaging part 6 may protrude diagonally downward.

  When the gap filler 1 is temporarily fixed by the fixture 21 and then heated, the foam 2 is first softened and has fluidity, but then foams and hardens. Since the hole 10 is opened in the foil body 4, the area where the foam 2 is exposed to the outside air through the hole 10 is expanded, the heat receiving area through the hole 10 is increased, and the foaming efficiency is improved. Even if the foam 2 is softened and has fluidity, the engagement portion 6 becomes the flow resistance of the softened foam 2, and the softened foam 2 is fluidized by the engagement portion 6 of the foil body 4. Is suppressed.

  Therefore, the softened foam 2 does not sag or fall down, and as shown in FIG. 4B, the foam 2 is foam-cured by heating and expands in the thickness direction of the gap filler 1. The air gap 34 is reliably closed. In addition, the foam 2 contracts as it cools, but contracts in such a way that the engaging part 6 is sandwiched between the foams 2, so that the foam 2 is reliably engaged with the engaging part 6 and hung down.

  Next, a gap filler 51 according to a second embodiment different from the above-described embodiment will be described with reference to FIG. In addition, about the same member as embodiment mentioned above, the same number is attached | subjected and detailed description is abbreviate | omitted.

  In the gap filler 51 of the second embodiment, the foil body 4 is provided over almost the entire surface of the foam 2, and the engaging portion 6 that protrudes toward the foam 2 and bites into the foam 2 is formed. ing. When the foil 2 is thick and the foil body 4 is provided on both sides, the fluidity of the foam 2 can be further suppressed and a large flow resistance can be obtained.

Next, the gap filling material 61 of the third embodiment will be described with reference to FIGS.
In the gap filler 61 of the third embodiment, the engaging portion 62 is formed in a bottomed cylindrical shape. The engaging portion 62 has a bottomed cylindrical shape in which a cylindrical pusher 64 is pressed from the foil body 4 side toward the foam body 2, the foil body 4 is pushed out to the foam body 2 side, and bites into the foam body 2. An engaging portion 62 is formed.

  Even in the engaging portion 62, as in the above-described embodiment, even when the foam 2 is softened by heating and the fluidity is increased, the engaging portion 62 becomes a flow resistance and the foam 2 is suspended. Suppress. The engaging portion 62 may be formed by forming a hole (not shown) in the foam 2 and then extruding it with the pushing tool 64. At this time, the foam 2 is in a state of being cured by being cooled to room temperature. May be.

  As shown in FIG. 8A, after the gap filler 61 is temporarily fixed to the inner panel 31 by the fixture 21, the outer panel 32 is overlapped with the inner panel 31 to form the rail 30 having the gap 34. When heated, the foam 2 initially softens and has fluidity, but then foams and hardens. Even when the foam 2 is softened and has fluidity, the engaging portion 62 becomes the flow resistance of the softened foam 2, and the softened foam 2 is fluidized by the engaging portion 62 of the foil body 4. Is suppressed.

  Therefore, the softened foam 2 does not sag or fall down, and the foam 2 is foam-cured by heating and expands in the thickness direction of the gap filler 61 as shown in FIG. The air gap 34 is reliably closed.

  The present invention is not limited to such embodiments as described above, and can be implemented in various modes without departing from the gist of the present invention.

It is a perspective view of the space | gap filler as one Embodiment of this invention. It is AA expanded sectional drawing of FIG. It is explanatory drawing which shows the manufacturing method of the space | gap filler as one Embodiment of this invention in order of a process. It is explanatory drawing of the state which has arrange | positioned the space | gap filler of this embodiment in the space | gap. It is an expanded sectional view of the space | gap filler of 2nd Embodiment. It is a perspective view of the space | gap filler of 3rd Embodiment. It is BB expanded sectional drawing of FIG. It is explanatory drawing of the state which has arrange | positioned the space | gap filler of 3rd Embodiment in the space | gap. It is explanatory drawing which attached the fixing tool to the space | gap filler of this embodiment. It is a front view of the fixing tool of this embodiment. It is a side view of the fixing tool of this embodiment. It is a front view of the fixing tool of another embodiment. It is a side view of the fixing tool of another embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,51,61 ... Space | gap filler 2 ... Foam 4 ... Foil body 6,62 ... Engagement part 8, 64 ... Extrusion tool 10 ... Hole 12 ... Extruder 21, 28 ... Fixing tool 22 ... Locking part 24 ... Connecting part 26 ... elastic piece part 27 ... hook part 29a ... slit 29b ... protrusion 30 ... rail 31 ... inner panel 32 ... outer panel 34 ... gap

Claims (6)

In the gap filler that expands by heating and fills the gap,
A foam body that is foam-cured by heating is formed into a sheet shape, and a foil body is overlaid on at least one surface of the foam body, and an engaging portion that protrudes toward the foam body and bites into the foam body is provided in the foil body. A void filler characterized by being formed into.   The void filler according to claim 1, wherein the foil body is formed of a material that does not soften at a temperature lower than a temperature at which the foam is foam-cured.   The gap filling material according to claim 2, wherein the material of the foil body is a metal foil body.   The gap filler according to any one of claims 1 to 3, wherein the engaging portion has a saddle shape.   The gap filler according to any one of claims 1 to 3, wherein the engagement portion has a bottomed cylindrical shape. An extrusion process for extruding a sheet-like foam that is foam-cured by heating;
A laminating step of superimposing a foil on the foam;
Forming the foil body with an engaging portion that protrudes into the foam body and bites into the foam body; and
Punching process according to the shape of the gap,
A method for producing a void filler, comprising:

Images