JP5771020B2 - Vehicle seat back frame structure - Google Patents

Description

  The present invention relates to a frame structure of a vehicle seat back using a fiber reinforced composite material.

  As a structure of a rear seat back frame for automobiles, a metal pipe material is arranged on the outer periphery, and a metal plate material such as a steel plate is arranged in an area surrounded by the pipe material, Due to the demand for reducing the vehicle weight, the seat back frame is also required to be lighter, and it is considered that the seat back frame is made of resin. For example, Patent Document 1 discloses a technique for integrally forming a hollow seat back frame by blow molding. In order to achieve further weight reduction, a seat back frame using a fiber reinforced composite material having excellent strength and rigidity has been devised. Patent Document 2 discloses a technique for integrally forming a seat back frame using a composite material including a thermoplastic matrix and reinforcing fibers. Patent Document 3 discloses a seat back frame structure in which a weak portion for breaking at a non-exposed portion when an excessive input is applied to a fiber reinforced composite material sheet.

  By the way, in recent years, various measures have been implemented to improve the collision safety of automobiles, and the seat belt for the center seat of the rear seat, which has been the mainstream so far, has been changed to a three-point system for improving passenger safety. There has been proposed a seat back frame in which a seat belt retractor is fixed to a rear seat back frame. Also, a front seat has been proposed in which a retractor is fixed to a seat back frame in a vehicle in which the C-pillar of the vehicle body is eliminated to improve boarding / exiting performance. In these cases, the seat back frame is required to maintain sufficient strength against the seat belt anchorage load specified in ECE-R14, and the retractor is securely fixed to the seat back frame. Is required. Patent Document 4 discloses a method of joining a metal frame and a resin frame body via a retractor support bracket in a seat back frame using a resin frame body and two metal frames in combination.

  However, since Patent Documents 1 to 3 are directed to a sheet that does not require the retractor to be fixed, no mention is made of the retractor fixing method. Moreover, in patent document 4, it has a structure where a metal frame bears most of the load, and most of the load input to the retractor is also carried by the metal frame. Therefore, it is clear that there is a limit to weight reduction because the number of metal usage sites increases.

Japanese Patent Laid-Open No. 03-061020 JP 2003-182417 A JP 2005-334364 A JP 2006-247066 A

  When the retractor is fixed to the seat back frame, the retractor is generally fastened to the seat back frame fixing point with a bolt or the like. After the seat belt is unwound from the retractor above the seat, the retractor body or its It is pulled out in the vehicle forward direction through some seat belt support member such as a part of the seat back frame main body or a part thereof, an unwinding guide. At this time, the tension applied to the seat belt acts as an upward pulling force on the above-described fixing point, and the tensile load applied to the front of the vehicle with respect to the seat belt support member and the seat belt support member downward. It acts as a load to push down. FIG. 1 schematically shows loads applied to a seat belt, a retractor, and a seat belt support member.

  When applying a fiber reinforced composite material to a seat back frame, the retractor will be fixed to the seat back frame through some metal inserts that function as nuts and bolts. When the mechanical fastening means used in the above is simply inserted into the fiber composite material, excessive stress acts on the insert portion, and in the worst case, the fastening portion may break.

  In the present invention, when a fiber reinforced composite material is applied to a seat back frame to achieve a significant weight reduction, a concentrated heavy load acting on a fixing point of a retractor may be distributed and applied to the fiber reinforced composite material member. An object of the present invention is to provide a seat back frame structure for a vehicle.

In order to solve this problem, the present inventors have reached the present invention as a result of intensive studies. That is, the present invention provides a vehicle seat back in which a main structure includes a seat back frame made of a fiber-reinforced composite material and a metal retractor support bracket, and the retractor is attached to the seat back frame via the retractor support bracket. A vehicle seat back frame structure, wherein the retractor support bracket is attached to the seat back frame by a joining method including at least fitting. The present invention also relates to a seat back having a panel body made of a fiber-reinforced composite material, and a frame body made of a fiber-reinforced composite material that is formed separately from the panel body and arranged on the outer periphery of the panel body. A vehicle seat back frame structure including a frame and a metal retractor support bracket, the retractor being attached to the seat back frame via the retractor support bracket, wherein the retractor support bracket is attached to the seat back frame The present invention also provides a vehicle seat back frame structure which is attached by a joining method including at least fitting and is sandwiched and fixed between the panel body and the frame body.

  According to the seat back frame structure described in the present invention, it is possible to efficiently transmit the tension acting on the seat belt without locally concentrating on the fiber reinforced composite material member. Significant weight reduction is possible.

It is the model which showed the load concerning a seatbelt, a retractor, and a seatbelt support member. It is a perspective view which shows 1st Embodiment of the seat back frame structure of this invention. It is a figure which shows the components structure of 1st Embodiment of the seat back frame structure of this invention. It is a three-view figure which shows 1st Embodiment of the seat back frame structure of this invention. It is an enlarged view showing a first embodiment of a seat back frame structure of the present invention. It is a perspective view which shows 2nd Embodiment of the seat back frame structure of this invention. It is a figure which shows the components structure of 2nd Embodiment of the seat back frame structure of this invention. It is a three-view figure which shows 2nd Embodiment of the seat back frame structure of this invention. It is an enlarged view which shows 2nd Embodiment of the seat back frame structure of this invention. It is a perspective view which shows 3rd Embodiment of the seat back frame structure of this invention. It is a figure which shows the components structure of 3rd Embodiment of the seat back frame structure of this invention. It is a three-view figure which shows 3rd Embodiment of the seat back frame structure of this invention. It is an enlarged view which shows 3rd Embodiment of the seat back frame structure of this invention. The cross-sectional shape example of the frame body of a seat back frame structure.

  Hereinafter, the case where the seat back frame structure of the present invention is applied to a rear seat back of a wagon type vehicle or a hatch back type vehicle will be described with reference to the drawings, but the present invention is not limited thereto.

[Fiber-reinforced composite materials]
The fiber-reinforced composite material in the seat frame back structure of the present invention includes reinforcing fibers and a matrix resin. The form of the reinforcing fiber in the fiber reinforced composite material may be a short fiber, a long fiber, or a continuous fiber, and two or more of these may be used in combination. A short fiber is a fiber having a fiber length of less than 0.1 to 10 mm, a long fiber is a fiber having a length of 10 to 100 mm, and a continuous fiber is a fiber having a fiber length of 100 mm or more. In the case of short fibers or long fibers, paper made using chopped strands or the like may be used. In the case of continuous fibers, it is also preferable that they are contained in the matrix resin in the form of a woven or knitted fabric, a sheet of a unidirectionally arranged strand and a sheet of a multiaxial woven fabric, or a nonwoven fabric. In addition, multiaxial woven fabrics are generally nylon yarns, polyester yarns, glass fibers, which are bundles of fiber reinforcements that are aligned in one direction and are laminated at different angles (polyaxial woven fabric base material). This refers to a woven fabric that is stitched by stitches such as yarns, penetrates the laminate in the thickness direction, and reciprocates between the front and back surfaces of the laminate along the surface direction. The fiber reinforced material constituting the fiber reinforced composite material molded body may be one in which reinforcing fibers are randomly dispersed or one having a specific fiber orientation, one in which reinforcing fibers are plane-oriented or uniaxially oriented, or those A combination or a laminate thereof is preferable.

  The fiber reinforced composite material in the seat back frame structure of the present invention may be a laminate or sandwich structure of a fiber reinforced composite material portion and a resin-only portion. In the case of a sandwich structure, the core member may be a composite material and the skin member may be a resin. Conversely, the core member may be a resin-only portion and the skin member may be a composite material.

[Matrix resin]
The matrix resin used in the seat back frame structure of the present invention is a thermoplastic resin or a thermosetting resin, preferably a thermoplastic resin or a composition thereof. Specifically, polycarbonate resin, polyolefin resin, polyester resin, acrylic resin, polylactic acid, polyamide resin, ASA resin, ABS resin, polyether ketone resin, polyether imide resin, polyphenylene ether resin, polyphenylene oxide resin, polysulfone resin , Polyethersulfone resin, polyetherimide resin, polyetheretherketone resin, polyphenylene sulfide resin, polyamideimide resin, phenol resin, epoxy resin, unsaturated polyester resin, melamine resin, polyurethane resin, polyimide resin, and these resins Although at least 1 sort (s) selected from the group which consists of 2 or more types of mixtures (resin composition) etc. chosen is mentioned, there is no restriction | limiting in particular. The resin composition includes a polycarbonate resin and polyester resin composition, a polycarbonate and ABS resin composition, a polyphenylene ether resin and a polyamide resin composition, a polyamide resin and an ABS resin composition, and a polyester resin and nylon. At least one selected from the group consisting of resin compositions and the like is preferred.

[Reinforcing fiber]
As the reinforcing fiber used in the seat back frame structure of the present invention, glass fiber, polyester fiber, polyolefin fiber, carbon fiber, para-aramid fiber, meta-aramid fiber, boron fiber, azole fiber, alumina fiber, etc. At least one selected from the above is mentioned as a preferable one, and a carbon fiber excellent in specific strength and specific elasticity is particularly preferable.

[Seatback frame structure]
The seat back frame structure of the present invention includes a seat back frame 1 whose main structure is made of a fiber reinforced composite material and a metal retractor support bracket 6, and the retractor 2 is interposed through the metal retractor support bracket 6. The retractor support bracket 6 is attached to the seat back frame 1 by a joining method including at least fitting. A preferred first embodiment of the seat back frame structure includes a panel body and a frame body arranged on the outer periphery thereof, and a preferred second embodiment includes a monocoque-shaped body, and a preferred third embodiment. As a form, what has the frame body integrally arrange | positioned around a retractor in addition to the panel body and the frame body arrange | positioned in the outer peripheral part is mentioned. The frame body integrally disposed around the retractor according to the third embodiment has a function of securely holding the retractor, and the retractor support bracket is joined to the seat back frame by a method including fitting. It also has a function as a fitting part.

Preferred embodiments of the seat back frame structure of the present invention will be described in detail with reference to the drawings, but the present invention is not limited thereto.
The seat back frame 1 may have a panel body 1B and a frame body 1A disposed on the outer periphery thereof as shown in the first or third embodiment (FIGS. 2 to 5 and FIGS. 10 to 13), As shown in the second embodiment (FIGS. 6 to 9), the monocoque-shaped body 1C may be used, and other shapes may be used. Moreover, it may be integrally molded and may be configured by combining a plurality of members.

  The seat back frame 1 may have a hinge mechanism 7 for attaching the seat back frame 1 rotatably, and a holding mechanism 8 for keeping the seat back frame 1 almost upright. Also good. The hinge mechanism 7 and the holding mechanism 8 are generally made of metal, but can be made of resin or fiber reinforced composite material.

  The main structure of the seat back frame 1 is a structure that handles most of the load. As an example, in the first or third embodiment (see FIG. 5 or FIG. 13), the frame body 1A, the second embodiment. In the form (see FIG. 9), a skin body 1D (see FIG. 9) can be mentioned. The portion other than the main structure may be a fiber reinforced composite material, a resin, or a metal depending on the degree of the applied load.

[Frame body]
When the seat back frame 1 in the seat back frame structure of the present invention includes the panel body 1B and the frame body 1A disposed on the outer periphery thereof as in the first or third embodiment, for example, the frame body 1A Is preferably composed of a fiber reinforced composite material, and the shape thereof corresponds to the seat back frame structure, and examples thereof include a substantially square shape, a trapezoidal shape, and an inverted trapezoidal shape. The shape of the corner may have a curvature or may be based on a straight line. Examples of the shape of the frame body 1A include an open cross-sectional shape or a closed cross-sectional shape. Here, the open cross-sectional shape is a shape having an open cross section, and the closed cross-sectional shape is a shape having a closed cross section. Examples of the open cross-sectional shape include a hat shape, a U-shape, a V-shape, and the like, and a structure having a joint portion with the panel body 1B is preferable. Examples of the open cross-sectional shape include a round pipe shape and a square pipe shape, and may be integrally formed, or a plurality of open cross-sectional shapes may be joined to form a closed cross-sectional shape. Taking the example in which the cross-sectional shape of the frame body 1A is a hat shape (FIG. 14), the definition of thickness and the like will be described. The thickness (symbol 12) of the frame body 1A is not particularly limited, but is preferably about 1 to 6 mm from the balance between strength and weight reduction. The thickness is preferably 5 mm or less, more preferably 4 mm or less. The height of the open section (symbol 13) is not particularly limited, but is preferably 10 mm or more and 100 mm or less, more preferably 40 mm or more and 60 mm or less. The width of the open section (symbol 14) is 10 mm or more and 100 mm or less, more preferably 20 mm or more and 40 mm or less. The width of the joining portion (symbol 15) may be any as long as joining is possible, but specifically, it is 5 mm or more and 50 mm or less, more preferably 10 mm or more and 30 mm or less. These may be uniform in the frame body or may be appropriately selected depending on the part of the frame. By adopting such a shape, the deformability of the frame body can be improved, so that efficient energy absorption is possible.

  With respect to the cross-sectional shape, for example, a draft can be arbitrarily added as long as the object of the present invention is not impaired from the viewpoint of performing press molding using a mold. The frame body 1A can be filled with a honeycomb material, foamed resin, paper, or the like.

[Panel body]
When the seat back frame 1 in the seat back frame structure of the present invention has the panel body 1B and the frame body 1A arranged on the outer periphery thereof as in the first or third embodiment, for example, the panel body 1B May be light and excellent in energy absorption, and can be selected from metals, resins, and the like. In the case of metal, high-strength steel or aluminum is preferable. In the case of a resin, a thermoplastic resin is preferable from the viewpoint of excellent moldability, productivity, and processability. Further, the panel body 1B may be a fiber reinforced composite material, and is preferably a fiber reinforced composite material including organic long fibers as reinforcing fibers and a thermoplastic resin as a matrix.

  The panel body 1B has a substantially flat plate shape and may be a single plate or a laminate. In the case of a laminate, it may be a laminate of the same kind of members, or a laminate of different members or a sandwich structure. Moreover, a rib can also be provided as needed. The thickness of the panel body 1B is not particularly limited, but is preferably about 1 to 5 mm from the balance between strength and weight reduction.

[Monocoque body]
When the seat back frame 1 in the seat back frame structure of the present invention is a monocoque body 1C as in the second embodiment, for example, the monocoque body 1C is a structure in which a skin body 1D is disposed around a core body 1E. Preferably there is. (Specific examples are shown in FIGS. 6 to 9) The skin body 1D preferably completely covers the core body 1E, but may be partially exposed. The skin body 1D is preferably made of a fiber reinforced composite material, and the core body 1E is preferably made of a material having a low specific gravity such as a honeycomb material, a foamed resin, or paper. Skin body 1D and core body 1E may be integrally formed in the mold, or may be configured by combining skin body 1D and core body 1E divided into a plurality of parts. The thickness of the monocoque body 1C is not particularly limited, but is preferably about 10 to 100 mm from the balance between strength and weight reduction. The thickness of the skin body 1E is not particularly limited, but is preferably about 1 to 6 mm from the balance between strength and weight reduction. The thickness of the skin body 1E is preferably 5 mm or less, more preferably 4 mm or less.

[Retractor support bracket]
The retractor support bracket 6 is a metal member having a retractor fastening portion 4 for fixing the retractor 2, and iron or aluminum is preferably used. As a method for fastening the retractor 2, bolt / nut joining is preferably used. As the manufacturing method, a cutting method, a pressing method, a casting method, or the like is preferably used, and a plurality of metal members may be joined by a method such as welding, rivet, bolt / nut, or adhesion. Although thickness does not have limitation in particular, it is preferable to manufacture with a metal plate of 5 mm or less, and thickness 1-3 mm is especially preferable. After securing the required strength, the meat removal processing or the thickness reduction processing for weight reduction may be performed.

  There may be at least one retractor fastening portion 4, and there may be an auxiliary fastening portion 4 </ b> B for suppressing rattling of the retractor 2. In this case, since the load acting on the auxiliary fastening portion 4B is smaller than that of the main fastening portion 4, the auxiliary fastening portion 4B may be integrated on the retractor support bracket 6 or the retractor support bracket 6. It may be provided on other parts, for example, on the seat back frame 1. What is important in the present invention is that the main retractor fastening portion 4 is provided on the retractor support bracket 6.

  The retractor support bracket 6 may have a hollow structure (A) 9 through which the seat belt 5 passes as shown in FIGS. 2 to 5. In this case, the tension by the seat belt 5 can be received efficiently. It becomes possible to reduce the plate | board thickness of the retractor support bracket 6, and further weight reduction is realizable. In this case, the width and height of the hollow structure are preferably larger than the dimension of the tongue of the seat belt, preferably about 10 to 30 mm in height and about 60 to 90 mm in width.

  The retractor support bracket 6 may have a hollow structure (B) 10 for reinforcing the fastening portion as shown in FIGS. 2 to 5. In this case as well, the tension by the seat belt 5 described above can be received efficiently. Therefore, the thickness of the retractor support bracket 6 can be reduced, and further weight reduction can be realized. In this case, the height and width of the hollow structure can be arbitrarily selected, but it is preferable that the width is about 10 to 70 mm and the height is about 1 to 20 mm.

[How to attach the retractor support bracket to the seat back frame]
Since the heavy load resulting from the tension of the seat belt 5 acts on the retractor support bracket 6, it is preferable that the retractor support bracket 6 be joined to the seat back frame 1 by a method including at least fitting. In this case, a part 11 of the retractor support bracket may be fitted to the inner surface of the frame body 1A having an open cross-sectional shape as shown in FIG. 5, and a monocoque shape body having a recess as shown in FIGS. A part 11 of the retractor support bracket may be fitted to 1C or the frame body 1A. In order to securely fix the retractor support bracket 6 to the seat back frame 1, the retractor support bracket is preferably sandwiched and fixed by a part of the members constituting the seat back frame. It is also preferable that the retractor support bracket 6 is sandwiched between at least two of the members. In this case, the seat back frame 1 may include a panel body 1B and a frame body 1A disposed on the outer periphery thereof, and the retractor support bracket 6 may be sandwiched between the panel body 1B and the frame body 1A. By adopting such a structure, it is possible to efficiently transmit the load in the vehicle traveling direction acting on the seat belt 5 in the event of a vehicle collision to the high-strength frame body 1A.

  In joining the retractor support bracket 6 to the seat back frame 1, it is desirable to use adhesion, welding, mechanical fastening, and the like in addition to fitting. It is also possible to insert the retractor support bracket 6 manufactured in advance into the mold as an insert part, and to join in the mold by insert molding. At this time, the retractor support bracket 6 can be subjected to a surface treatment for increasing the bonding strength.

[Seat belt support member]
After the seat belt 5 is unwound from the retractor 2 to the upper side of the seat, the seat belt 5 is pulled out in the forward direction of the vehicle via the seat belt support member 3. At this time, the seat belt support member 3 is an independent structure. A part of the components constituting the retractor 2 may have the function, and a part of the retractor support bracket 6 may have the function. Further, a part of the seat back frame 1 and a part of the parts attached thereto may have the function.

[Parts to which the present invention is applicable]
The seat back frame structure of the present invention can be suitably applied to a rear seat of a wagon type vehicle or a hatch back type vehicle, but may be applied to other vehicles such as a sedan type vehicle. It can also be applied to a front seat.

DESCRIPTION OF SYMBOLS 1 Seat back frame 1A Frame body 1B Panel body 1C Monocoque-shaped body 1D Skin body 1E Core body 2 Retractor 3 Seat belt support member 4 Retractor fastening part 4B Retractor fastening part (auxiliary)
5 Seat belt 6 Retractor support bracket 7 Hinge mechanism mounting portion 8 Holding mechanism mounting portion 9 Hollow structure (A)
10 Hollow structure (B)
11 Fitting portion 12 Frame body thickness 13 Open section height 14 Open section width 15 Open section joint width

Claims (7)

A panel body made of a fiber reinforced composite material, and a seat back frame having a frame body made of a fiber reinforced composite material formed separately from the panel body and disposed on the outer periphery of the panel body; A retractor support bracket, wherein the retractor is attached to the seat back frame via the retractor support bracket, and the retractor support bracket includes at least a fitting to the seat back frame. A vehicle seat back frame structure, wherein the vehicle seat back frame structure is fixed by being sandwiched between the panel body and the frame body .   The vehicle seat back frame structure according to claim 1, further comprising a frame body integrally disposed around the retractor. The vehicle seat back frame structure according to claim 1 or 2 , wherein the retractor support bracket has a hollow structure (A) through which a seat belt passes. The vehicle seat back frame structure according to any one of claims 1 to 3 , wherein the retractor support bracket has a hollow structure (B) for reinforcing a retractor fastening portion. The vehicle seat back frame structure according to any one of claims 1 to 4 , wherein the reinforcing fibers of the fiber-reinforced composite material are carbon fibers. The vehicle seat back frame structure according to any one of claims 1 to 5 , wherein the matrix resin of the fiber-reinforced composite material is a thermoplastic resin. A rear seat of a wagon type vehicle or a hatchback type vehicle having the vehicle seat back frame structure according to any one of claims 1 to 6 .

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