JP5929724B2 - Airbag cover and manufacturing method thereof - Google Patents

Description

  The present invention relates to an airbag cover including a door portion that is pushed and opened by an airbag when inflated with a thin integral hinge portion as a rotation center, and a manufacturing method thereof.

  Conventionally, as an airbag cover, a thin-walled integral hinge portion is used as a center of rotation, and it is configured to include a door portion that is pushed and opened by an airbag when inflated, and a main body portion having an integral hinge portion, In order to reinforce the integral hinge part of the main body part, there is a structure including a reinforcing part disposed on the back side of the main body part (see, for example, Patent Document 1). Note that the main body portion is made of a hard material having shape retaining properties than the reinforcing portion, and the reinforcing portion is formed of a soft material extending from the main body portion.

  In the manufacture of the airbag cover, the reinforcing part is molded in advance, and the reinforcing part is set on the molding die of the main body part, and the main body part is molded to manufacture the airbag cover, or the main body part is reinforced. The airbag cover was manufactured by forming the reinforcing portion by applying and curing the coating material for forming the portion.

Japanese Patent Laid-Open No. 11-32476

  However, since the conventional airbag cover has a configuration in which the reinforcing portion is disposed on the entire back surface side of the main body portion, there is a space for applying the mold for forming the reinforcing portion and the coating material for forming the reinforcing portion. Widely needed, there was room for improvement.

  The present invention solves the above-described problems, and an object of the present invention is to provide an air bag cover that can be manufactured in a space-saving and resource-saving manner at low cost, and a manufacturing method thereof.

The airbag cover according to the present invention is configured to include a door portion that is pushed by the airbag when inflated and opened with the thin integral hinge portion as a rotation center,
A main body portion having the integral hinge portion, and a reinforcing portion arranged on the back side of the main body portion to reinforce the integral hinge portion,
The main body portion is made of a hard material having shape retaining property than the reinforcing portion, and the reinforcing portion is a synthetic resin airbag cover formed from a soft material extending from the main body portion,
The reinforcing part is
As a configuration partially arranged in a sheet shape on the back side of the main body,
It is formed from a resin material having compatibility with the main body, and is fixed to the back surface of the main body by injection molding.

  And, in the method of manufacturing an airbag cover according to the present invention, the main body portion is molded in advance, set in the injection mold of the reinforcement portion, and on a predetermined portion on the back side of the main body portion by injection molding, If the reinforcing portion is formed, the airbag cover of the present invention can be manufactured.

  That is, in the airbag cover of the present invention, the reinforcing part for reinforcing the integral hinge part is configured to be partially disposed in the form of a sheet on the back side of the main body part and is injected to the back side of the main body part. Since the structure is formed by molding, the injection mold for molding the reinforcing portion can be made compact, and the airbag cover can be manufactured in a small space. Of course, the material for forming the reinforcing portion can also be reduced, and can be manufactured as a resource saving.

  Therefore, according to the airbag cover and the manufacturing method thereof according to the present invention, the airbag cover can be manufactured at low cost in a space-saving and resource-saving manner.

Further, in the airbag cover according to the present invention, the airbag cover is configured as a long pillar garnish attached to the inside of the pillar portion of the vehicle,
The main body portion is provided with an assembly seat for assembling a plurality of clips for attaching the pillar garnish to the vehicle body side along the longitudinal direction of the main body portion, and the integral hinge portion is disposed on the main body portion. When it is arranged and arranged in a range from one edge along the longitudinal direction to at least one assembly seat and to at least the other assembly seat,
The reinforcing portion is arranged on the back surface side of the main body portion excluding the assembly seat and the vicinity thereof, and in a range from the edge of the main body portion to a position before reaching the other one of the assembly seats. It only has to be configured.

  In such a configuration, it is not necessary to form the reinforcing portion on the assembly seat formed so as to be raised on the back surface side of the main body portion or the vicinity thereof. It can be formed in a planar manner, and the entire region of the reinforcing portion can be easily and evenly disposed on the back side of the main body portion. That is, it is possible to avoid a state in which the reinforcing portion is partially thick, so that the material used for the reinforcing portion can be reduced as much as possible, and the injection mold of the reinforcing portion can be made compact.

  And in the manufacturing method of the above pillar garnish (airbag cover), the structure which exposes the assembly seat vicinity of a main-body part can be employ | adopted regarding the injection mold of a reinforcement part, and after shaping | molding of a main-body part, a clip is used. In parallel with the assembling operation for assembling the corresponding assembling seat, it is possible to perform the molding operation for injection molding the reinforcing portion, and the pillar garnish can be efficiently manufactured.

  In other words, if the pillar garnish is manufactured by the method as described above, the pillar garnish can be manufactured with the same tact time as when the pillar garnish is formed from one kind of resin material. Therefore, if the resin material when forming the pillar garnish from one kind of resin material is difficult to obtain or is expensive, compared to such a pillar garnish, it is simple and low-cost, A pillar garnish can be manufactured.

  That is, when the airbag cover is formed from, for example, one type of thermoplastic elastomer, the resin material includes various reinforcing materials such as talc and filler that increase rigidity, or rubber components that increase flexibility. It becomes a material filled with a filler, which is difficult to obtain or expensive. However, if, for example, the main body is formed from an unfilled type olefin resin and the reinforcing portion is formed from an olefin thermoplastic elastomer to form an airbag cover (pillar garnish), these are generally In particular, the airbag cover (pillar garnish) can be easily and inexpensively manufactured because it is easily available and low in cost.

  And in the airbag cover of the present invention, even if two types of forming materials are used, it can be manufactured with the same tact time as when the airbag cover is formed from one type of resin material. Compared to the airbag cover formed from the above, when the forming material to be used is low cost without increasing the manufacturing man-hour, the airbag cover is manufactured at a low cost coupled with the suppression of the manufacturing man-hour increase. be able to.

It is a figure which shows the use condition of the pillar garnish of one Embodiment of this invention. It is a schematic sectional drawing of the II-II site | part of FIG. It is a schematic sectional drawing of the III-III site | part of FIG. It is a figure which shows the back surface side of the pillar garnish of embodiment. In the pillar garnish of an embodiment, it is an outline fragmentary enlarged perspective view showing the back side of the field of the upper end side. It is a figure which shows the state which shape | molds the reinforcement part of embodiment. It is a figure explaining the assembly | attachment operation | work of the clip performed in parallel at the time of shaping | molding of the reinforcement part of embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the embodiment, a pillar garnish (front pillar garnish) 20 disposed on the vehicle inner side I of the front pillar portion FP in the vehicle will be described as an example of the airbag cover. The pillar garnish (hereinafter simply referred to as “garnish”) 20 of the embodiment is, as shown in FIG. 1, air folded from the rear pillar portion RP of the vehicle through the roof side rail portion RR to the front pillar portion FP. A part of the airbag cover 18 of the head protection airbag apparatus M configured to dispose the bag 12 is configured.

  In the present specification, the up / down / front / rear / left / right directions coincide with the up / down / front / rear / left / right directions of the vehicle with reference to the mounting state on the vehicle unless otherwise specified.

  As shown in FIG. 1, the head protection airbag device M includes an airbag 12, an inflator 15 that supplies inflation gas to the airbag 12, and an airbag cover that covers the vehicle interior I of the folded airbag 12. 18.

  The airbag 12 is folded into a long shape that can reduce the width in the vertical direction, and on the upper edge side of the opening SW of the vehicle interior I, the rear pillar portion RP, the roof side rail portion RR, and the front pillar portion. The mounting bracket 13 is fixed to a plurality of mounting portions (not shown) along the front-rear direction on the upper edge side when expansion is completed, and the mounting bracket 13 is attached to the body 1 side together with the mounting bracket 13. It is attached and fixed to the body 1 side of the vehicle. In the case of the embodiment, the airbag 12 includes a belt portion 12a on the lower end side of the front portion when the inflation is completed. This belt portion 12a is used to exert tension on the lower edge side of the airbag 12 when the inflation is completed to prevent the airbag 12 from moving to the outside of the vehicle. The front end side is attached and fixed to the body 1 side on the lower side of the front pillar portion FP with the mounting bracket 13 fixed. Specifically, the front end of the belt portion 12a is fixedly attached to the body 1 side at a position near the lower side of the clip 33 for attaching the garnish 20 to the body 1 side. In the case of the embodiment, the airbag 12 is connected to the inflator 15 on the rear end side when the inflation is completed.

  As shown in FIG. 1, the inflator 15 is a cylinder type whose outer shape is a substantially cylindrical shape, and is disposed in the region of the rear pillar portion RP. More specifically, the inflator 15 is configured such that a mounting bracket 16 made of sheet metal is disposed around the rear end of the airbag 12 and the mounting bracket 16 is bolted to the body of the rear pillar portion RP. It is fixed on one side. The inflator 15 is covered with the rear pillar garnish 10 on the inner side of the vehicle.

  In the embodiment, the airbag cover 18 includes a garnish 20 and a lower edge 9 a of the roof head lining 9.

  Then, the mounting of the head protection airbag device M of the embodiment on a vehicle will be described. First, the airbag 12 is folded, the attachment bracket 13 is attached to each attachment portion of the airbag 12, and the airbag 12 The inflator 15 is attached to the end side using the attachment bracket 16. The folded airbag 12 is wrapped around by a breakable wrapping material for preventing collapse to form an airbag assembly. Next, the mounting brackets 13 and 16 are attached to the body 1 side, and the airbag assembly is attached and fixed to the body 1 side. Thereafter, if the rear pillar garnish 10, the garnish (front pillar garnish) 20, and the roof head lining 9 are attached to the body 1, the head protecting airbag device M can be mounted on the vehicle.

  As shown in FIGS. 1 to 3, the garnish 20 of the embodiment is attached and fixed to the vehicle interior I of the front pillar body 3 on the body 1 side. The front pillar body 3 includes a reinforcement panel 4, an outer panel 5, and an inner panel 6 each made of a steel plate. The inner panel 6 has an opening that is opened to fix the garnish 20. A stop hole 7 and a mounting hole 8 are formed. The locking hole 7 is formed in the vicinity of the center of the front pillar portion FP in the vertical direction, and the mounting hole 8 is formed in the vicinity of the upper end of the front pillar portion FP for attaching the garnish 20 to the inner panel 6 respectively. The clips 33 and 34 are inserted.

  The garnish 20 attaches the main body 21 to the inner panel 6, the main body 21 configured to cover the vehicle interior I of the front pillar portion FP over the entire region, the reinforcing portion 31 disposed on the back side of the main body 21. And clips 33 and 34 for the purpose. In the case of the embodiment, two clips 33 and 34 are used along the longitudinal direction of the main body 21.

  The main body portion 21 is made of a hard material having shape retaining properties, and is formed from an unfilled type olefin resin by injection molding. In the case of the embodiment, the main body portion 21 is made of unfilled type polypropylene (PP). The main body 21 is formed so as to protrude from the long general part 22 having a substantially U-shaped cross-section covering the vehicle inside I of the front pillar part FP, and the vehicle outer side O surface (the back surface 22a side) of the general part 22. And assembly seats 27 and 28 to which the clips 33 and 34 are assembled. Two assembling seats 27 and 28 are provided side by side along the longitudinal direction of the general portion 22, and are integrally formed with the general portion 22 so as to protrude from the back surface 22 a side of the general portion 22. . On the lower end 22d side of the general portion 22, it is inserted between the side panel 2 on the body 1 side and an instrument panel (not shown), and moves to the vehicle outer side O or the vehicle inner side I on the lower end 22d side of the general portion 22. The insertion piece 23 to prevent is formed (refer FIG. 1).

  The general portion 22 is configured to cover the inner side I of the folded airbag 12 by the region on the rear side of the assembly seats 27 and 28, and is a door that is pushed open by the airbag 12 that is inflated on the rear edge 22b side. The part 25 is disposed (see FIGS. 2 and 5). The door portion 25 has a thin integral hinge portion 24 disposed on the front edge side, and when the airbag 12 is inflated with the integral hinge portion 24 as a rotation center, as shown by a two-dot chain line in FIG. It is the structure which opens so that 25a may face the vehicle inner lower side. In the case of the embodiment, as shown in FIG. 2, the integral hinge portion 24 is configured by cutting out the vehicle outer side surface (back surface 22 a) of the general portion 22 into a V-shaped cross section. Along the longitudinal direction, the upper end edge 22c on the upper end side of the general portion 22 (main body portion 21) extends from the upper mounting seat 28 to the lower mounting seat 27. It is continuously arranged in the range up to this side. Specifically, the integral hinge portion 24 is formed from the upper end edge 22 c of the general portion 22 to a region about １ ／ of the upper side of the region between the assembly seats 28 and 27. In the garnish 20 of the embodiment, the clip 34 to be assembled to the upper assembly seat 28 is configured to be assembled to the assembly seat 28 in two stages, and the clip 34 is assembled at the site of the initial locking portion 36. The garnish 20 is attached to the inner panel 6 in a state of being assembled to the periphery of the assembly hole 29 of the seat 28, but when the airbag 12 is inflated, an initial locking portion to the periphery of the assembly hole 29 of the assembly seat 28 The bulging portion 37a on the distal end side of the anchor portion 37 formed so as to extend from the initial locking portion 36 is unlocked at the periphery of the assembly hole 29 so that it cannot be removed. Become. That is, in the garnish 20 of the embodiment, when the airbag 12 is inflated, the locking of the initial locking portion 36 to the periphery of the assembly hole 29 is released, so that the entire region on the upper side of the main body portion 21 is kept on the vehicle interior side. While being moved to I, the door portion 25 opens with the integral hinge portion 24 as the rotation center, and the airbag 12 protrudes.

  On the back surface 22a side of the general portion 22, a large number of reinforcing thin plate-like reinforcing ribs 26 are juxtaposed along the longitudinal direction of the general portion 22 so as to protrude to the back surface 22a side (see FIG. 4). ). The reinforcing ribs 26 are formed on both edge sides in the lateral direction in the upper region, and are also formed in the region on the back side of the door portion 25. The reinforcing ribs 26 arranged on the back surface side of the door portion 25 serve as spacers when the airbag 12 is inflated. By arranging the reinforcing ribs 26 on the back surface side of the door portion 25, the airbag is arranged. The door part 25 can be opened quickly at the time of 12 expansion | swelling expansion | swelling.

  As shown in FIG. 3, the assembly seat 27 for assembling the clip 33 includes a ceiling wall 27 a disposed on the vehicle outer side O away from the general portion 22, a peripheral wall 27 b that connects the ceiling wall 27 a and the general portion 22, The clip 33 is assembled so as to project to the vehicle outer side O in an assembly hole (not shown) formed in the ceiling wall 27a.

  As shown in FIG. 2, the assembly seat 28 for assembling the clip 34 includes a ceiling wall 28 a disposed on the vehicle outer side O away from the general portion 22, a peripheral wall 28 b connecting the ceiling wall 28 a and the general portion 22, An assembly hole 29 for assembling the clip 34 is provided in the ceiling wall 28a. The assembly hole 29 is set to a size that allows the initial locking portion 36 of the clip 34 to be locked to the peripheral edge and that the bulging portion 37a of the anchor portion 37 of the clip 34 cannot be inserted.

  As shown in FIGS. 2, 4, and 5, the reinforcing portion 31 is disposed on the back surface 22 a side of the general portion 22 in the main body portion 21 so as to reinforce the integral hinge portion 24. The reinforcing portion 31 is formed of an olefin-based thermoplastic elastomer (TPO) that is compatible with polypropylene (PP) constituting the main body portion 21. In the case of the embodiment, the reinforcing portion 31 is fixedly disposed by injection molding on the back surface 22a of the main body portion 21 (general portion 22) manufactured in advance by injection molding. Specifically, the reinforcing portion 31 is a region on the back surface 22a side of the general portion 22 excluding the assembly seat 28 disposed on the upper side and the vicinity of the periphery thereof, and the upper end of the general portion. It is arrange | positioned in the range from the edge 22c to the near side which reaches the assembly seat 27 arrange | positioned below. More specifically, the reinforcing portion 31 corresponds to the arrangement position of the integral hinge portion 24 and fills the notch portion constituting the integral hinge portion 24 while covering the entire back surface side of the integral hinge portion 24 including the periphery. From the upper end edge 22c of the general portion 22 to the region of about 1/3 of the upper side of the region between the assembly seats 28 and 27, the general portion 22 is disposed (see FIGS. 4 and 5). More specifically, the reinforcing portion 31 bypasses the arrangement position of the reinforcing rib 26 and the arrangement position of the assembly seat 28, and is rearward of the assembly seat 28 in the region from the upper end edge 22 c to the assembly seat 28. In the region below the assembly seat 28, the width dimension is made larger than that in the upper region, and the region in the width direction (short direction) side is about the rear half. Further, it is disposed up to the rear edge side.

  In the garnish 20 of the embodiment, the thickness dimension of the general part 22 in the main body part 21 is set in the range of 2.5 to 3 mm, and the thickness of the integral hinge part 24 is set to about 0.5 mm. ing. Moreover, the thickness of the reinforcement part 31 is set to about 0.8 mm. Specifically, as the unfilled polypropylene (PP) constituting the main body 21, the flexural modulus (JIS K 7171) is 1222 MPa, the Izod impact strength (JIS K 7110) is normal temperature (23 ° C.). 70 J / m, measurement is impossible due to cracking at low temperature (−40 ° C.), tensile elongation at break (JIS K 7113) is 40%, and tensile yield stress (JIS K 7161) is 27 MPa. . Further, as the olefin thermoplastic elastomer (TPO) constituting the reinforcing portion 31, specifically, the flexural modulus (JIS K 7171) is 275 to 600 MPa, the Izod impact strength (JIS K 7110) is normal temperature ( No breakage at 23 ° C, physical properties of 510 J / m or higher at low temperature (-40 ° C), tensile elongation at break (JIS K 7113) of 500% or higher, and tensile yield stress (JIS K 7161) of 10 MPa or higher Is used.

  The clip 33 assembled to the assembly seat 27 is made of a synthetic resin such as an olefin-based thermoplastic elastomer, and protrudes from the ceiling wall 27a of the assembly seat 27 toward the vehicle outer side O as shown in FIG. The latch leg 33a is configured to be provided with the latch leg 33a, and the garnish 20 is attached to the inner panel 6 by latching the latch leg 33a to the periphery of the latch hole 7 formed in the inner panel 6. The clip 33 is in a locked state with the periphery of the locking hole 7 of the locking leg 33a when the locking of the clip 34 arranged on the upper side with the peripheral edge of the assembly hole 29 of the initial locking portion 36 is released. It will be released.

  The clip 34 to be assembled to the assembly seat 28 is made of a synthetic resin such as an olefin-based thermoplastic elastomer and protrudes from the ceiling wall 28a of the assembly seat 28 toward the vehicle outer side O as shown in FIG. The mounting leg 35, the initial locking part 36 locked to the periphery of the mounting hole 29 formed in the ceiling wall 28a of the mounting seat 28, and the anchor part 37 extending from the initial locking part 36 to the vehicle inner side I. And. The anchor portion 37 is housed in the assembly seat 28 (in the portion surrounded by the ceiling wall 28a and the peripheral wall 28b), and is configured to bulge the tip side. The bulge portion 37a on the tip side is The size is set so that the assembly hole 29 cannot be inserted. The clip 34 attaches the garnish 20 to the inner panel 6 by locking the attachment leg 35 to the periphery of the attachment hole 8 formed in the inner panel 6. The attachment force of the attachment leg 35 to the periphery of the attachment hole 8 is large, and the clip 34 is not easily detached from the attachment hole 8. In the clip 34, when the airbag 12 is inflated, when the door 25 is pressed by the inflating airbag 12, the engagement state between the peripheral edge of the assembly hole 29 of the assembly seat 28 and the initial engagement portion 36. Will be released, and the entire portion of the general portion 22 in the vicinity of the assembly seat 28 (the entire portion on the upper end side) will move toward the vehicle inner side I. The movement of the entire portion of the general portion 22 in the vicinity of the assembly seat 28 toward the vehicle inner side I is stopped when the bulging portion 37a provided on the distal end side of the anchor portion 37 comes into contact with the peripheral portion of the assembly hole 29. The Rukoto.

  And the garnish 20 of embodiment is manufactured by injection-molding the reinforcement part 31 in the main-body part 21 previously injection-molded using the small injection molding machine 41 as shown in FIG.

  As shown in FIG. 7, the injection molding machine 41 includes a molding die 42 that covers only a part of the main body 21 set with the back surface 22a facing upward. The mold 42 is configured to cover only the portion where the reinforcing portion 31 is formed in the main body portion 21, and as shown in FIG. 6, in the front and back direction of the general portion 22 (up and down direction in FIG. 6). Two split molds 43 and 44 that are opened and closed are provided. The split mold 43 has a mold surface 43 a that matches the surface of the general part 22, and the split mold 44 has a mold surface 44 a that matches the back surface 22 a of the general part 22 and molds the reinforcing part 31. . Further, the split mold 44 includes a recess 45 that penetrates along the opening / closing direction (up and down direction in FIGS. 6 and 7) so as to expose the vicinity of the assembly seat 28 disposed in the vicinity of the reinforcing portion forming portion. Yes.

  In the garnish 20 of the embodiment, the main body portion 21 that has been injection-molded in advance is set in an injection molding machine 41, the molding die 42 is closed, and the molding material F that forms the reinforcing portion 31 is transferred from the gate 42b into the cavity 42a. When the filling and filling of the molding material F are completed and the molding material F is solidified, the reinforcing portion 31 can be formed by opening the molding die 42. Further, in the embodiment, the molding die 42 of the injection molding machine 41 is configured to cover only the reinforcing part forming part in the main body part 21 (general part 22), and the split mold 44 is arranged in the vicinity of the reinforcing part forming part. Since the recessed portion 45 that exposes the assembly seat 28 is exposed, the two assembly seats 27 and 28 are exposed in a state in which the mold 42 is closed. At the time of injection molding, the clips 33 and 34 can be assembled to the assembly seats 27 and 28 at the same time. And if the reinforcement part 31 is formed and the clips 33 and 34 are assembled | attached to each assembly seat 27 and 28, the garnish 20 can be manufactured.

  And in the garnish 20 (airbag cover) of embodiment, the reinforcement part 31 for reinforcing the integral hinge part 24 is partially arrange | positioned in the sheet form at the back surface 22a side of the main-body part 21 (general part 22). Since it is configured to be formed by injection molding on the back surface 22a side of the main body portion 21 (general portion 22), the injection molding die 42 for molding the reinforcing portion 31 can be made compact and saved. The garnish 20 can be manufactured in space. Of course, the material for forming the reinforcing portion 31 can also be reduced and can be manufactured as a resource saving.

  Therefore, in the garnish 20 (airbag cover) and the manufacturing method thereof according to the embodiment, the garnish 20 can be manufactured at low cost as a space-saving resource.

  In the garnish 20 of the embodiment, the integral hinge portion 24 is extended from one end edge (the upper end edge 22c of the general portion 22) over the assembly seat 28 along the longitudinal direction of the main body portion 21. The reinforcing portion 31 is arranged in the range up to the front of the seat 27, and the reinforcing portion 31 is on the back surface 22a side of the main body portion 21 (general portion 22) excluding the mounting seat 28 and the vicinity thereof, and the general portion. The upper end edge 22c is disposed in the range from the front end to the assembly seat 27. Therefore, in the garnish 20 of the embodiment, it is not necessary to form the reinforcing portion 31 on the assembly seat 28 formed so as to protrude on the back surface 22a side of the main body portion 21 (general portion 22) or in the vicinity thereof. The reinforcing portion 31 can be easily formed planarly on the back surface 22a side of the main body portion 21 (general portion 22), and the entire area of the reinforcing portion 31 is thin and even on the back surface 22a side of the main body portion 21 (general portion 22). It becomes easy to arrange in. That is, it is possible to avoid a state in which the reinforcing portion 31 is partially thick, so that the material used for the reinforcing portion 31 can be reduced as much as possible, and the injection mold 42 of the reinforcing portion 31 can be made compact.

  And in the garnish 20 of embodiment, since the recessed part 45 is provided in the split mold 44 of the shaping | molding die 42 which forms the reinforcement part 31, and it is set as the structure which exposes the assembly seat 28 vicinity from this recessed part 45, it is the structure of the main-body part 21. After molding, in parallel with the assembling work for assembling the clips 33 and 34 to the corresponding assembling seats 27 and 28, the molding work for injection molding the reinforcing portion 31 can be performed, and the garnish 20 is efficiently manufactured. be able to.

  In other words, if the garnish 20 is manufactured by the method as in the embodiment, the pillar garnish can be manufactured in the same tact time as when the pillar garnish is formed from one kind of resin material. Therefore, if the resin material when forming the pillar garnish from one kind of resin material is difficult to obtain or is expensive, compared to such a pillar garnish, it is simple and low-cost, The garnish 20 can be manufactured.

  That is, when the airbag cover is formed from, for example, one type of thermoplastic elastomer, the resin material includes various reinforcing materials such as talc and filler that increase rigidity, or rubber components that increase flexibility. It becomes a material filled with a filler, which is difficult to obtain or expensive. However, in the embodiment, the main body portion 21 is formed from unfilled type polypropylene (PP), the reinforcing portion 31 is formed from an olefin-based thermoplastic elastomer (TPO), and the garnish 20 is formed. Since these are generally easy to obtain and low in cost, the garnish 20 can be manufactured easily and at low cost.

  And in the garnish 20 of embodiment, even if it uses two types of forming materials, since it can manufacture with the same tact time as the case where an airbag cover (pillar garnish) is formed from one type of resin material, it is one type. Compared with an air bag cover (pillar garnish) formed from a resin material, it is possible to manufacture an air bag cover at a low cost without increasing the number of manufacturing steps and coupled with the low cost of the material used. .

  If such a point is not taken into consideration, the garnish may be manufactured by using the slide core structure or the like to form the reinforcing portion by the same molding machine at the time of injection molding of the main body portion.

  In the embodiment, the pillar garnish (front pillar garnish) 20 used in the head protecting airbag device M is described as an example, but the airbag cover to which the present invention is applicable is limited to this. Instead, for example, the present invention may be applied to an airbag cover of an airbag device for a passenger seat disposed in front of the passenger seat.

DESCRIPTION OF SYMBOLS 20 ... Garnish (pillar garnish), 21 ... Main body part, 22 ... General part, 22a ... Back surface, 22c ... Upper end edge, 24 ... Integral hinge part, 25 ... Door part, 27, 28 ... Assembly seat, 31 ... Reinforcement Part 33, 34 ... clip, 41 ... injection molding machine, 42 ... molding die (injection molding die), M ... head protection airbag device.

Claims (4)

With a thin integral hinge part as the center of rotation, it is configured to have a door part that is pushed and opened by the airbag during inflation,
A main body portion having the integral hinge portion, and a reinforcing portion arranged on the back side of the main body portion to reinforce the integral hinge portion,
The main body portion is made of a hard material having shape retaining property than the reinforcing portion, and the reinforcing portion is a synthetic resin airbag cover formed from a soft material extending from the main body portion,
The airbag cover is configured as a long pillar garnish that is attached to the inside of the pillar portion of the vehicle,
The main body portion is provided with an assembly seat for assembling a plurality of clips for attaching the pillar garnish to the vehicle body side along the longitudinal direction of the main body portion, and the integral hinge portion is disposed on the main body portion. Along the longitudinal direction, from one edge, over at least one assembly seat, and at least before reaching the other assembly seat, is arranged and configured,
The reinforcing part is
Partially in the form of a sheet on the back side of the main body excluding the assembly seat and the vicinity thereof , and in the range from the end edge of the main body to the other assembly seat. As the arrangement,
An airbag cover formed of a resin material having compatibility with the main body and fixedly disposed on the back surface of the main body by injection molding. The main body is formed of an unfilled type olefin resin,
The airbag cover according to claim 1 , wherein the reinforcing portion is formed of an olefin-based thermoplastic elastomer. With a thin integral hinge part as the center of rotation, it is configured to have a door part that is pushed and opened by the airbag during inflation,
A main body portion having the integral hinge portion, and a reinforcing portion arranged on the back side of the main body portion to reinforce the integral hinge portion,
The manufacturing method of a synthetic resin airbag cover in which the main body portion is made of a hard material having shape retaining properties than the reinforcing portion, and the reinforcing portion is made of a soft material extending from the main body portion. And
The airbag cover is configured as a long pillar garnish that is attached to the inside of the pillar portion of the vehicle,
The main body portion is provided with an assembly seat for assembling a plurality of clips for attaching the pillar garnish to the vehicle body side along the longitudinal direction of the main body portion, and the integral hinge portion is disposed on the main body portion. Along the longitudinal direction, from one edge, over at least one assembly seat, and at least before reaching the other assembly seat, is arranged and configured,
The reinforcing part is
Partially in the form of a sheet on the back side of the main body excluding the assembly seat and the vicinity thereof , and in the range from the end edge of the main body to the other assembly seat. As a structure to be arranged and formed from a resin material having compatibility with the main body part,
After the body portion is molded, the reinforcing portion is formed on the back surface of the body portion by injection molding in parallel with the assembly operation for assembling the clip to the corresponding assembly seat. Manufacturing method of airbag cover. The main body is formed of an unfilled type olefin resin,
The method for manufacturing an airbag cover according to claim 3 , wherein the reinforcing portion is formed of an olefin-based thermoplastic elastomer.

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