JP2009190516A - Back pad and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a back pad capable of reducing vibration (resonance toward a seated occupant) and excellent in productivity. <P>SOLUTION: The back pad for a vehicle comprises a main body formed of formed resin and a weight, and at least a part of the weight is embedded in the formed resin in the back pad for the vehicle, and its manufacturing method is also provided. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicular back pad, and more particularly to a back pad that can reduce vibration transmitted from a seat back mounted on a metal back frame to an occupant seated on the back pad.

  Conventionally, a vehicular seat back in which a back pad of an automobile or the like is mounted on a metal back frame has been problematic in that vibrations from the metal back frame are easily transmitted to a seated passenger. In order to solve this problem, a mass body made of a thick iron plate is provided on the upper part of the seat back frame, or a solidified low melting point metal is filled in the pipe-like up frame (Patent Document 1). A so-called mass damper (dynamic damper) that lowers the resonance frequency of the frame is used.

  However, since these methods attach an additional weight to the frame, a process for assembling the sheet is necessary, and it cannot be said that productivity is high.

JP 11-208330 A

  The use of weights such as the thick steel plate and solidified low melting point metal described above requires the process of attaching the weights to the back pad as described above, which increases the number of man-hours. There is also a problem.

  An object of the present invention is to provide a back pad with reduced vibration (and hence resonance with a seated occupant) and excellent productivity.

  A further object of the present invention is to provide a back pad manufacturing method with reduced vibration and excellent productivity.

The above purpose is
A vehicle back pad consisting of a foamed resin body and weight,
A vehicle back pad, wherein at least a part of the weight is embedded in the foamed resin;
Can be achieved.

Preferred embodiments of the vehicle back pad of the present invention are listed below.
(1) When the weight is integrally formed with the foamable resin composition, at least a part of the weight is embedded in the foamed resin. The foamable resin composition is preferably a urethane foam-forming resin composition.
(2) The foamed resin is urethane foam.
(3) The weight is embedded in the center or both sides of the upper part of the back side (opposite the backrest) of the back pad.
(4) The back pad has a through hole for the headrest at the top, and is embedded in the vicinity of the through hole inside the back pad.
(5) The weight is a high-density material such as a metal plate. A metal plate is preferred.
(6) The mass of the weight is 0.1 to 2 kg. An appropriate vibration suppression effect of the seat back can be obtained, and resonance to the seated occupant can be remarkably prevented.

The vehicle back pad of the present invention described above,
Using a molding die consisting of an upper mold and a lower mold having a core, a weight or a secondary material with a weight fixed thereto is attached to the upper mold core, and a foamable resin composition is injected into the lower mold. It can be advantageously obtained by a production method characterized by foam molding.

  The auxiliary material is preferably a reinforcing cloth for covering the back surface of the back pad.

  Moreover, the said preferable aspect of a vehicle back pad is applicable also to the said manufacturing method of this invention.

  In the present invention, the installation of a heavy object (weight) such as an iron plate for suppressing resonance from the back pad of the back sheet to the occupant, for example, when forming the foamable resin composition on the back pad, By forming the weight together, a back pad with a heavy object can be obtained in one process such as forming without separately installing a heavy object. For this reason, a back pad with a weight can be easily obtained with reduced man-hours.

  Therefore, the back pad of the present invention is excellent in productivity because vibration (resonance to the passenger) is reduced.

  The back pad of the present invention has a basic configuration including a back pad body and a weight at least partially embedded therein.

  The perspective view of the vehicle seat provided with the back pad of the present invention of Drawing 1 is shown. The vehicle seat 1 includes a seat cushion pad 2 and a back pad 4 with a weight. The back pad main body 3 of the back pad 4 with a weight has a central portion 3M in the left-right width direction and left and right side portions 3S.

  FIG. 2 is a front view of an example of the back pad with a weight of the present invention, and FIG. 2 is a sectional view taken along the line A-A ′.

  The back pad main body 3 of the back pad 4 with a weight has a center part 3M in the left-right width direction and left and right side parts 3S, and a weight 5 is embedded in the upper part. A reinforcing cloth 6 is provided on the back surface of the back pad body 3 (generally formed integrally with the pad). A through hole for inserting the headrest mounting protrusion may be provided in the upper portion of the back pad main body 3.

  The upper part of the back pad 3 is bent into a “U” shape, and a weight 4 is embedded in the bent inner portion. The shape of the weight 4 is a “U” shape, but may be a “<” shape or a flat plate, and the shape is not particularly limited. The “U” shape is preferable because it is easily fixed and provides a certain area. Further, the weight 4 is not plate-shaped but may be any shape such as a lump, but a plate-like shape is preferable for integral molding.

  Although one weight 5 is embedded in the upper part of the back pad main body 3 in the drawing, two or more weights, for example, two, may be arranged in a distributed manner. In the drawing, the weight 5 is almost completely embedded in the back pad main body 3, but may be partially embedded. The weight 5 only needs to be in a state that does not easily move, and the embedded state is not limited. Further, the position of the weight 5 is not particularly limited as long as it is the upper part of the back pad main body 3, but it is generally preferable to be above the center, particularly near the upper part.

  The weight 5 (in the case of a plurality of weights) is preferably 0.1 to 2 kg. If it is less than the lower limit, the vibration suppressing effect is not sufficient, and if it exceeds the upper limit, installation tends to be difficult. The area in the case of a plate is preferably 1/100 to 1/10 of the surface area of the back pad main body 3. If it is less than the lower limit, the vibration suppressing effect may not be sufficient, and if it exceeds the upper limit, the sitting comfort will be adversely affected.

  The material of the weight 5 is more suitable as it has a higher density, and a metal material is generally preferable. Examples thereof include alloys such as iron, copper, tin, zinc, and stainless steel. Iron and stainless steel are preferred. Other than the metal material, for example, ceramic and rubber can be used.

  The reinforcing cloth 6 is integrated by foam molding of the foamable resin composition so as to cover the back surface of the back pad main body 3, the inner surface of the upper portion of the pad, and the inner surface of the overhanging portion of the “U”. . The reinforcing cloth 6 can be used without particular limitation as long as it has appropriate air permeability and can prevent the foamable resin composition from leaching out during molding. A knitted fabric or a laminated composite of these can be used.

  The reinforcing cloth 6 is formed into a bag shape by sewing a base cloth cut into a predetermined shape, or using a fastener such as a stapler or a tag pin (a pin generally used for fastening a tag such as a plastic stapler). Has been. The reinforcing cloth 6 is mounted in a mold and laminated and integrated on the back surface of the back pad main body 3 by foam molding.

  The back pad body 3 is a foamed resin, generally a urethane foam, and is preferably a flexible urethane foam, a semi-rigid urethane foam, particularly a flexible urethane foam. Commercially available products can be used.

  The foamable resin composition for forming the foamed resin is preferably a urethane foam-forming resin composition. The resin composition for forming a urethane foam is generally formed by mixing an alcohol component such as polyether polyol, polyester polyol, and polymer polyol, and a polyol component containing water, and a polyisocyanate component such as tolylene diisocyanate and diphenylmethane diisocyanate. Things are common.

  As the polyether polyol, a polyoxyalkylene polyol in which a polyfunctional alcohol compound is used as an initiator and an alkylene oxide is added thereto is preferably used. Examples of the polyfunctional alcohol compound include ethylene glycol, propylene glycol, glycerin, trimethylolpropane, triethanolamine, diethanolamine, and compounds obtained by adding a small amount of alkylene oxide to these. Examples of the alkylene oxide that undergoes addition polymerization include those having 2 or more carbon atoms, such as ethylene oxide, 1,2-propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, and styrene oxide. Etc. can be illustrated. Among these alkylene oxides, those containing propylene oxide and / or butylene oxide in combination with ethylene oxide and containing an oxyethylene unit at the terminal are preferable.

  The polymer polyol is obtained by dispersing polymer particles in the form of fine particles in a polyol compound. Examples of the polymer particles include addition polymerization polymers such as homopolymers or copolymers of vinyl monomers such as acrylonitrile, styrene, alkyl methacrylate, and alkyl acrylate, and condensation polymerization polymers such as polyester, polyurea, and melamine resin. As a method for introducing such polymer particles into a polyol compound, for example, when the polymer particles are an addition polymerization polymer, styrene, acrylonitrile, etc. in a polyol such as polyoxyalkylene polyol in the presence of a radical polymerization initiator. And a method of polymerizing the vinyl monomer.

  The polyisocyanate component is a mixture of tolylene diisocyanate (TDI) and diphenylmethane diisocyanate (MDI) (including purified MDI (p-MDI) and crude MDI (c-MDI)). Although not limited, it is preferably 10/90 to 90/10 in weight ratio.

Water is used as a foaming agent and is preferably blended in an amount of 2 to 4 parts by weight with respect to 100 parts by weight of the polyol compound. When the amount of water exceeds 4 parts by weight, foaming is excessive when forming a back pad by vacuum molding, making it difficult to ensure sufficient hardness. In addition, various additives such as a crosslinking agent, an emulsifier, an antioxidant, an ultraviolet absorber, an anti-aging agent, a filler, a flame retardant, and a plasticizer can be added as necessary.

  Examples of the catalyst include triethylenediamine, bis (N, N-dimethylamino-2-ethyl) ether, N, N, N ′, N′-tetramethylhexamethylenediamine, and bis (2-dimethylaminoethyl) ether. An amine-based catalyst is preferably used, and the amount used is usually 0.05 to 10 parts by weight with respect to 100 parts by weight of the polyol compound. In particular, in order to promote initial foaming, it is preferable to use an unblocked immediate-acting amine catalyst rather than a block-type catalyst.

  As the foam stabilizer, various silicone foam stabilizers such as dimethylsiloxane, polyether dimethylsiloxane, and phenylmethylsiloxane are preferably used, and the amount used is an active ingredient with respect to 100 parts by weight of the polyol compound. Is usually 0.01 to 5 parts by weight.

  Next, the manufacturing method of the back pad for vehicles of this invention is demonstrated.

  FIG. 4 shows a cross-sectional view of a mold used in the manufacturing method of the back pad with weight. The molding die 40 is rotatably provided via a lower die 42 that is recessed so as to mold the surface side portion of the pad body 4 and a hinge portion that is disposed on one side of the lower die 42. An upper die 43 that opens and closes the upper surface opening of the lower die 42 is provided. The upper die 43 is a die that molds the back surface side of the pad body 4, and a cavity that is a foaming space corresponding to the pad shape is formed between the upper die 43 and the lower die 42 by closing the upper surface opening of the lower die 43. The upper mold 43 is provided with a core 44 for forming the “U” -shaped overhanging portion. By moving downward by the driving device, the core 44 is detached from the upper mold 43 and opened.

  For example, the core 44 may be provided with a convex portion for forming a through hole for fitting the headrest mounting protrusion.

  When foaming the back pad of the present invention using the mold 40, first, the weight 5 is fixed to the upper portion of the core 44. Pins, magnets, adhesives, etc. are used for fixing. You may fix to the convex part for shape | molding the through-hole for inserting the said protrusion for headrest attachment. Alternatively, the bag-like reinforcing cloth 6 may be fixed to the weight in advance with an adhesive or the like, and the weight 5 with the reinforcing cloth may be fixed to the upper portion of the core 44. This method is preferable because workability is improved.

  Next, after injecting the urethane foam-forming resin composition into the cavity of the lower mold 42 using an injector (not shown), the upper mold 43 is closed to seal the cavity. Thereby, the resin composition for forming urethane foam fills the cavity while foaming.

  In this way, by foaming and filling the urethane foam-forming resin composition in the cavity, the back pad main body 3 made of polyurethane foam is foam-molded, and the weight 5 and the reinforcement 6 are integrally molded on the back surface thereof. After molding, the upper die 43 is opened, and the core 44 is further detached from the upper die 43 to open the die and then removed, thereby obtaining the back pad 4 shown in FIG. 3 of the present invention. Foam molding is generally performed under conditions of room temperature to 120 ° C. and 1 to 30 minutes (preferably room temperature to 100 ° C. and 5 to 20 minutes), although it depends on the resin composition for forming urethane foam.

  As described above, according to the present invention, since a weight effective for preventing resonance can be simultaneously mounted at the time of foaming the back pad, there is no need to carry out a process of mounting the weight at the time of manufacturing the back sheet.

The perspective view of one example of the vehicle seat provided with the back pad of the present invention of Drawing 1 is shown. It is a front view of one example of an embodiment of a back pad with a weight of the present invention. FIG. 3 is a sectional view taken along line A-A ′ of FIG. 2. It is sectional drawing of the metal mold | die used for the manufacturing method of the back pad with a weight of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle seat 2 Seat cushion pad 4 Back pad with weight 3 Back pad main body 3M Central part 3S Side part

Claims (10)

A vehicle back pad consisting of a foamed resin body and weight,
A vehicle back pad, wherein at least a part of a weight is embedded in a foamed resin.   The vehicular back pad according to claim 1, wherein the weight is integrally formed with the foamable resin composition.   The vehicle back pad according to claim 1, wherein the foamed resin is urethane foam.   The back pad for vehicles according to claim 2 whose foaming resin composition is a resin composition for urethane foam formation.   The back pad for vehicles according to any one of claims 1 to 4, wherein the weight is embedded in the center or both sides of the upper part of the back side of the back pad.   The back pad for vehicles according to any one of claims 1 to 4, wherein the back pad has a through hole for a headrest at an upper portion and is embedded in the vicinity of the through hole inside the back pad.   The back pad for vehicles according to any one of claims 1 to 6, wherein the weight is a metal plate.   The vehicle back pad according to any one of claims 1 to 7, wherein the weight has a mass of 0.1 to 2 kg.   Using a molding die consisting of an upper mold and a lower mold having a core, a weight or a secondary material having a weight fixed thereto is attached to the core of the upper mold, and a foamable resin composition is injected into the lower mold. The method of manufacturing the back pad for vehicles of any one of Claims 1-8 by foam-molding.   The method for manufacturing a vehicle back pad according to claim 9, wherein the auxiliary material is a reinforcing cloth for covering the back surface of the back pad.

Images