JP5242088B2 - Automotive seat cushion - Google Patents

Description

  The present invention relates to a cushion for an automobile seat, and more particularly to an automobile seat cushion and a cushion used for a seat back that have a soft feeling of sitting and backrest.

  A general automobile seat cushion (seat) or seat back (back) is formed by covering the surface of a polyurethane foam foam-molded using a mold with a skin material made of fabric or the like. A polyurethane foam can change hardness etc. arbitrarily by changing the mixing | blending of a polyurethane raw material, etc. variously. For this reason, various types of hardness from soft to hard are used for automotive seat cushions and seat backs using polyurethane foam.

  However, especially in the seat cushion of the driver's seat, the human body should be able to maintain the driver's posture according to various road conditions and driving conditions when driving on the road surface, and not to make the driver feel tired. Corresponding to each part, those having partially different hardness are required. In response to this requirement, various types of seat cushions have been developed and used. Typical examples of these are slab urethane foam sheets made of a softer material than polyurethane foam, which are bonded to a predetermined part of polyurethane foam with an adhesive, and similar slab urethane foam sheets are foam molded. For example, a polyurethane raw material is injected and integrally foamed after being placed in a mold. Furthermore, without placing a sheet of slab urethane foam in the mold, polyurethane raw materials of different blends are injected and foamed into predetermined predetermined sections in the foam mold, and polyurethane foams with partially different hardnesses are obtained. Molded and used.

However, the seat cushions having partially different hardnesses as described above have their respective problems. Examples of using slab urethane include a problem related to an adhesive for slab urethane, a problem that the hardness of the slab urethane is increased by impregnating the slab urethane with a polyurethane raw material, and the like. In addition, in the method of molding polyurethane foams having different hardnesses using polyurethane raw materials of different blends, even if horizontal sections can be made for different hardnesses, the same hardness is maintained in the vertical direction. There is a problem that comes out. In order to solve these problems, the present applicant has already proposed the technique disclosed in Patent Document 1. In the technique, as shown in FIG. 6, a groove 61 having a side surface and a bottom surface in which the skin layer 62 does not exist is formed in a seating portion of the molded polyurethane foam 60 by post-processing. Then, the presence of the groove 61 in the front-rear direction of the vehicle facilitates compressive deformation of the seating portion and makes the seated person feel soft.
JP 09-76797 A

  As one of the features of the technique disclosed in Patent Document 1, the skin layer 62 formed when the polyurethane raw material is foam-molded does not exist on the side surface and the bottom surface of the groove 61 cut and formed by post-processing. There is. For this reason, the rigidity of the side surface of the groove 61 is reduced, and the compression deformation around the groove 61 is facilitated, so that a person who is seated feels a soft feeling as described above.

  However, while the protrusion 63 receives a load and deforms, the seated person surely feels soft. However, if the projecting portion 63 is repeatedly compressed to the vicinity of the bottom surface of the groove 61 without the skin layer, the projecting portion 63 will be sag due to compression set and repeatedly compressed so that the projecting portion 63 falls down. Then, the protrusion 63 is easily deformed while being in a collapsed state. Further, when the projecting portion 63 is compressed to the vicinity of the bottom surface of the groove 61, the portion that receives the load is changed to a general portion of the polyurethane foam in which the groove 61 does not exist, so the repulsive force against the load is slightly increased at a stretch. The sensitive seated person feels so-called bottoming.

  In addition, seating performance requirements for seat cushions and seat backs using polyurethane foam cushions are increasing year by year. For example, there is an increasing demand for contradictory functions such as appropriate hardness required for posture holding and softness to reduce fatigue of each part of the body. Therefore, even though the formation of the grooves 61 arranged in parallel only in the front-rear direction of the vehicle is not particularly problematic in terms of production technology, as shown in FIG. In order to obtain a feeling, it has been found that when the groove 71 is processed so as to go straight across the groove 61, the surface to be processed bends and escapes.

  On the other hand, when the groove 61 and the groove 71 are formed in a lattice shape, the air in the groove 61 and the groove 71 can move without being restricted in any direction. The characteristic that air permeability is ensured by the absence of the layer has diminished its meaning.

  Furthermore, there is a profile processing technique that is a conventional technique for forming uneven surfaces of various shapes and pitches on the surface of a cushion in a bed or the like. This profile processing is applied to a workpiece having a flat surface, but is difficult to apply to a material having a three-dimensional curved surface such as a seat cushion or a seat back. Therefore, the profile processing technique cannot be applied instead of using the technique of Patent Document 1. Of course, the profile processing technique is a processing method for removing the skin layer of the polyurethane foam. Therefore, the surface from which the skin layer has been removed by profile processing tends to sag when subjected to repeated pressure or lateral displacement from a skin material such as a car seat cushion or seat back. There is.

  The present invention has been made paying attention to such problems existing in the prior art. The purpose is to be able to place any part where the seated person can feel a soft feeling, especially when it is used in the seat cushion seat or seat back back, and there is little stagnation and ventilation. It is an object of the present invention to provide a cushion for an automobile seat made of polyurethane foam which does not have a problem of safety.

In order to solve the above problems, the invention of a cushion for an automobile seat according to claim 1 is directed to a cushion for an automobile seat comprising a polyurethane foam integrally foam-molded with a molding die. A plurality of protrusions that are covered with a skin layer on the entire surface and spaced apart by a lattice-shaped separation portion are arranged side by side, and the protrusions are defined as inner sides that are separated from left and right side portions with respect to the longitudinal direction of the automobile. The protrusions formed in the central portion and arranged in the inner central portion are divided and arranged in a portion having a large number of protrusions per one area and a portion having a small number of protrusions, and the width of the separation portion in the portion having a small number of protrusions is large. It is characterized in that it is wider than the width of the separated portion . The “cushion” used here is an elastic material such as polyurethane foam, which is in a state before being formed as an automobile seat covered with a skin material, and used as a seat. It is distinguished from the seat cushion of an automobile seat. In addition, here, “the entire surface is covered with the skin layer”, but the case where the entire surface of the protrusion is not necessarily covered with the skin layer without a gap is also included. For example, the case where the skin layer is not partially formed by a void or the like corresponds to the case where the skin layer is not only covered with no gap.

Invention according to claim 2, in cushions for automotive seats according to claim 1, wherein the polyurethane foam be those used as the seat cushion, the number of projections per the same area, the seat cushion The front side is less than the rear side. The “seat cushion” used here represents a seat portion of an automobile seat composed of a seat portion and a backrest, and is used separately from the backrest.

The invention according to claim 3, in cushions for automotive seats according to claim 1, wherein the polyurethane foam be those used as the seat back, the number of projections per the same area, the seat back There are more lower sides than the upper side. The “seat back” used here represents the back of an automobile seat composed of a seat and a backrest, and is used separately from the seat.

According to a fourth aspect of the present invention, in the cushion for an automobile seat according to any one of the first to third aspects, the protrusion has a shape in which a cone is placed on the upper end of the column body and integrated. It is characterized by being.

According to a fifth aspect of the present invention, in the automotive seat cushion according to any one of the first to third aspects, the protrusion is formed by integrating a prismatic body on an upper end of a truncated pyramid. It is characterized by being.

According to a sixth aspect of the present invention, in the automotive seat cushion according to any one of the first to fourth aspects, the protrusion is formed by integrating a cylindrical body on the upper end of the truncated cone. It is characterized by being.

(Function)
In the cushion of the automobile seat according to the present invention, a projection covered with a skin layer is formed on the seating portion or the backrest portion. Therefore, even if the compressive force of the human body, for example, the buttocks or the waist, repeatedly acts, the degree of occurrence of sag or deformation due to compression set can be reduced. Then, after the protrusion is appropriately elastically deformed, the entire polyurethane foam is elastically deformed to support the buttocks and the waist and maintain the posture. For this reason, the elastic deformation of the protrusions gives a soft feeling, and the entire polyurethane foam can elastically hold each part of the human body without impairing the soft feeling. Further, in the seating portion, if the number of projections at the front part against which the thighs are contacted is smaller than the number of projections at the rear part against which the buttocks contact, the degree of the soft feeling at the front part becomes stronger than that at the rear part. Therefore, the seated person does not feel a feeling of pressure in the thigh even though the buttocks are firmly held. Similarly, in the backrest, if the number of lower protrusions against which the waist hits is greater than the number of upper protrusions against which the back hits, the lower part will not feel softer than the upper part, but the waist will run in the car. Even if affected by the lateral acceleration of the time, it will be held firmly. Moreover, the back can feel a soft feeling without feeling a pressure.

  According to the present invention, a seat for a seat cushion and a backrest portion of a seat back can be arbitrarily arranged with a soft feeling part, and there is little sag and there is no problem of breathability. A seat cushion can be provided.

(First embodiment)
DESCRIPTION OF EMBODIMENTS Hereinafter, a first embodiment of a cushion for an automobile seat embodying the present invention will be described with reference to FIGS.

  FIG. 1 is a perspective view showing an automobile seat 1 including a seat cushion 2 and a seat back 3 using an automobile seat cushion embodying the present invention. FIG. 2 is a partial perspective view showing the protrusion 40 formed on the polyurethane foam. FIG. 3 is a cross-sectional view showing a part of a cross section passing through the center of the protrusion 40 shown in FIG. 2 and parallel to one side of the column body 42.

  As shown in FIG. 1, the seat cushion 2 has a side portion 23 defined by front and rear grooves 25 located on both left and right sides. A front portion 21 and a rear portion 22 are partitioned by a lateral groove 24 in the central portion between the left and right side portions 23. In the front part 21 and the rear part 22, the front part 21 has fewer projections 40 per area. The protrusions 40 are integrally formed when the polyurethane foam is formed using a foaming mold, and the entire surface is substantially covered with the skin layer. Here, “substantially” indicates that the entire surface of the protrusion 40 is not necessarily covered with a skin layer without a gap. That is, the skin layer may not be sufficiently formed due to large and small voids.

  The protrusions 40 shown in FIGS. 2 and 3 have a shape in which a rectangular pyramid 41 is placed on the upper end of a rectangular parallelepiped column 42, and adjacent protrusions 40 have a predetermined distance with a lattice-shaped separation portion 44 interposed therebetween. Only separated. In the present embodiment, the protrusion 40 formed on the rear portion 22 has a width L1 = 3 mm of the separation portion, an opposite side length L2 = 20 mm of the column body 42, a height H1 = 5 mm of the column body 42, and a height H2 of the protrusion 40 = The corners of the column 42 and the quadrangular pyramid 41 are chamfered with a curved surface having a radius of 1.5 to 2 mm. On the other hand, the protrusion 40 formed on the front portion 21 is different from the protrusion 40 formed on the rear portion 22 only in the width L1 of the separation portion 44, and the width L1 = 6 mm. Thus, since the width of the separation portion 44 of the front portion 21 is wider than that of the rear portion 22, the number of protrusions 40 per the same area is larger in the front portion 21 in comparison between the front portion 21 and the rear portion 22. Less. Therefore, the number of the protrusions 40 that support the thigh of the seated person is small, and the load received by one protrusion 40 from the thigh increases, so that the protrusion 40 is easily compressed and deformed. Therefore, the seated person feels that the repulsive force from the front part 21 received by the thigh is smaller than the repulsive force from the rear part 22 received by the buttocks, and the touch becomes soft.

  Since the protrusion 40 of the present embodiment is a quadrangular pyramid 41, when a load is applied from above the protrusion 40, the protrusion 40 can be easily deformed despite being covered with the skin layer. Therefore, when a seated person sits on the seat cushion 2, the initial repulsive force received on the thigh is the repulsive force accompanying the deformation of the quadrangular pyramid 41 and is extremely weak, and thus feels sufficiently soft to the seated person. It is done.

  Further, as shown in FIG. 1, the seat back 3 has side portions 33 defined by front and rear grooves 35 located on both the left and right sides. A lower part 31 and an upper part 32 are defined by a lateral groove 34 in the central part between the left and right side parts 33. In the lower part 31 and the upper part 32, the lower part 31 has a larger number of protrusions 40 per the same area. The forming method and shape of the protrusion 40 are the same as those described above for the seat cushion 2, but the rear portion 22 and the lower portion 31 of the seat cushion 2 correspond to the effects of the number and the difference in the number of protrusions 40. The front portion 21 and the upper portion 32 correspond to each other. In other words, in the present embodiment, the rear portion 22 and the lower portion 31 have the same width L1 and opposite side length L2 shown in FIG. 3, and the same heights H1 and H2. Similarly, in the upper portion 32 and the front portion 21, the width L1 and the opposite side length L2 are the same, and the heights H1 and H2 are the same.

According to the cushion of the automobile seat of the above embodiment, the following effects can be obtained.
(1) In the above embodiment, the front part 21 and the rear part 22 are partitioned in the central part between the left and right side parts 23 of the seat cushion 2, and the front part 21 has the number of projections 40 per the same area of the rear part 22. It is running low. Therefore, the protrusions 40 formed on the front part 21 that receives a load from the thigh receive a compressive force with a relatively small number. Therefore, since the protrusion 40 is easily deformed and does not cause the thigh to feel a repulsive force, the seated person can obtain a softer feel in the thigh compared to the buttocks.

  (2) In the above embodiment, the lower portion 31 and the upper portion 32 are partitioned in the central portion between the left and right side portions 33 of the seat back 3, and the lower portion 31 has a larger number of protrusions 40 per the same area. . Therefore, the protrusions 40 formed on the upper portion 32 that receives a load from the back are easily deformed by receiving a compressive force with a relatively small number and do not feel a repulsive force on the back. Therefore, the occupant can get a softer feel on the back than the lumbar region, and the lumbar region also receives a relatively hard feeling in the soft sensation, so the occupant is firmly supported by the lumbar region. Can.

  (3) In the above embodiment, the shape of the protrusion 40 is integrated by placing the quadrangular pyramid 41 on the upper end of the column body 42. Therefore, when a load is applied to the protrusion 40 by a seated person, the top of the quadrangular pyramid 41 is easily deformed, unlike the case where the shape of the protrusion 40 does not change in the vertical direction. Then, when the compressive force reaches the column body 42, the column body 42 is also deformed, and the initial repulsive force of the protrusion 40 can make the seated person feel soft.

  (4) In the above-described embodiment, the separation portions 44 are provided between the adjacent protrusions 40 and arranged in a lattice shape. Therefore, when the protrusions 40 are repeatedly compressed and deformed, the air in the separation portion 44 is formed in a lattice shape. It is possible to move through the communicating separation portion 44. Therefore, although the protrusion 40 is substantially covered with the skin layer, the cushion using the polyurethane foam on which the protrusion 40 of this embodiment is formed can exhibit air permeability.

(Second Embodiment)
Next, a second embodiment of an automobile seat cushion embodying the present invention will be described with reference to FIGS. Since the second embodiment has a configuration in which the shape of the protrusion 40 of the first embodiment is changed to the protrusion 50, detailed description of the same parts is omitted.

  FIG. 4 is a perspective view showing a part of the polyurethane foam on which the protrusions 50 of the present embodiment are formed. 5A is a cross-sectional view showing a part of a cross section passing through the center of the protrusion 50 in FIG. 4 and parallel to one side of the prismatic body 51, and FIG. 5B is a cross-sectional view similar to FIG. It is sectional drawing of the state from which the adjacent protrusion 50 was separated only predetermined distance compared with the case of (a). The protrusion 50 shown in FIG. 4 has a shape in which a rectangular column 51 that forms a rectangular parallelepiped is placed on the upper end of the quadrangular frustum 52, and the adjacent protrusion 50 when arranged vertically and horizontally in the rear part 22 or the lower part 31 is One side of the bottom of each square frustum 52 is shared.

  In the present embodiment, the protrusion 50 formed on the rear portion 22 or the lower portion 31 has an opposite side length L3 = 23 mm of the bottom side of the quadrangular frustum 52, an opposite side length L31 = 10 mm of the prism 51, and a height H3 of the square frustum 52. Each corner is chamfered with a curved surface having a radius of 1.5 to 2 mm, assuming that = 5 mm and the height H4 of the protrusion 50 = 10 mm. On the other hand, the protrusions 50 formed on the front part 21 or the upper part 32 have the same shape as the protrusions 50 formed on the rear part 22 or the lower part 31, but the arrangement of the protrusions 50 formed on the rear part 22 or the lower part 31 is the same. In contrast, as shown in FIG. 5B, adjacent protrusions 50 are arranged without sharing a part of the base of each quadrangular pyramid. The protrusions 50 formed on the front part 21 or the upper part 32 are spaced by a distance L4 = 3 mm at the front part 21 between the adjacent protrusions 50, and similarly by a distance L4 = 3mm at the upper part 32. Are spaced apart from each other and are arranged vertically and horizontally. As a result, the front part 21 or the upper part 32 has fewer projections 50 per area than the rear part 22 or the lower part 31. Therefore, in the case of the seat cushion using the cushion in which the protrusion 50 of the present embodiment is formed, as in the first embodiment, the soft feeling can be exhibited by reducing the protrusion 40 per the same area. However, the front portion 21 is relatively softer than the rear portion 22. Similarly, in the seat back, the upper portion 32 is relatively softer than the lower portion 31.

  The protrusion 50 of the present embodiment has a shape in which a rectangular column 51 that forms a rectangular parallelepiped is placed on the upper end of the quadrangular frustum 52 and integrated. For this reason, when a load is applied from the upper part of the protrusion 50, the prism body 51 transmits a compressive force to the lower quadrangular frustum 52 while being uniformly deformed. The quadrangular frustum 52 to which the compressive force is transmitted increases its volume as it goes downward, and deforms while gradually increasing the repulsive force against the compressive force. Finally, the polyurethane foam in which the compressive force is below the quadrangular frustum 52 Will act. In the process of deformation due to the compression force acting in this way, the repulsive force felt by the seat occupant from the protrusion 50 and the polyurethane foam gradually changes, so that the feeling of bottoming is not felt.

Therefore, according to the second embodiment, in addition to the effects described in the first embodiment, the following effects can be obtained.
(1) In the second embodiment, since the projection 50 is integrated by placing the rectangular column 51 that forms a rectangular parallelepiped on the upper end of the quadrangular frustum 52, the projection 50 is appropriately subjected to the load from the seated person as described above. In addition, deformation occurs so that the repulsive force gradually increases. Therefore, in addition to making the seated person feel a soft feeling, the seated person can feel a soft feeling over a long period of time without being easily sagged by a load repeatedly applied through the skin material.

In addition, you may change the said embodiment as follows.
In the embodiment described above, the shape of the protrusion 40 is integrated by placing the quadrangular pyramid 41 on the upper end of the rectangular parallelepiped column 42. On the other hand, the column body 42 may be another column body, for example, a columnar shape, and a pyramid having a surface having the same shape as the upper end, for example, a cone, may be integrated on the upper end of the column body. .
-In above-mentioned embodiment, although the processus | protrusion 40 was arrange | positioned at the predetermined location of the polyurethane foam vertically and horizontally, you may arrange | position the processus | protrusion 40 in the arrangement | sequence which cross | intersects diagonally.
In the above-described embodiment, the protrusions 40 are arranged at predetermined positions on the polyurethane foam at the same pitch. However, the protrusion pitch 40 is not the same pitch, but the arrangement pitch is changed, for example, the rear portion 22 has a pitch at the central portion compared to the left and right. May be increased.
In the above-described embodiment, the shape of the protrusion 50 is integrated by placing the rectangular column 51 that forms a rectangular parallelepiped on the upper end of the quadrangular frustum 52. On the other hand, the quadrangular frustum 52 may be another pyramid, for example, a triangular frustum or a hexagonal frustum, and a prismatic body having a bottom surface with the same shape as that of the upper end may be mounted on the upper end thereof.
In the above-described embodiment, the shape of the protrusion 50 is integrated by placing the rectangular column 51 that forms a rectangular parallelepiped on the upper end of the quadrangular frustum 52. On the other hand, the rectangular frustum 52 may be a truncated cone and a cylindrical body may be placed on the upper end of the truncated pyramid and integrated. In this case, when the adjacent protrusions 50 are arranged so that a part of the outer periphery of the bottom surface of the truncated cone is in contact with each other, the number of protrusions 50 per unit area is maximized.

(A) is a perspective view showing the seat for motor vehicles which consists of a seat cushion and a seat back which materialized the present invention, and (b) is a sectional view of the seat cushion in the vehicle width direction. The partial perspective view which shows the protrusion of 1st Embodiment of this invention. Sectional drawing which shows a part of cross section which passes along the center of protrusion of 1st Embodiment of this invention, and is parallel to one side of a rectangular parallelepiped. The partial perspective view which shows the protrusion of 2nd Embodiment of this invention. (A) is sectional drawing which shows a part of cross section which passes along the center of protrusion of 2nd Embodiment of this invention, and is parallel to one side of a rectangular parallelepiped, (b) is sectional drawing similar to (a), but it adjoins Sectional drawing of a state in which the protrusions are separated by a predetermined distance. The partial cross section figure which shows a prior art. The partial cross section figure which shows the case where the prior art is changed.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Car seat, 2 ... Seat cushion, 3 ... Seat back, 40, 50 ... Protrusion, 21 ... Front part, 22 ... Rear part, 23, 33 ... Side part, 31 ... Lower part, 32 ... Upper part, 41 ... Square pyramid , 42 ... pillar body, 51 ... prismatic body, 52 ... square frustum

Claims (6)

A cushion for an automobile seat made of a polyurethane foam integrally foam-molded with a molding die, wherein a plurality of surfaces are covered with a skin layer on the surface of the polyurethane foam and spaced apart by a lattice-shaped spacing portion. Side by side ,
The protrusion is formed in an inner central portion that is separated from the left and right side portions with respect to the longitudinal direction of the automobile,
The protrusions formed in the central portion are arranged so as to be divided into a portion having a large number of protrusions per area and a portion having a small number of protrusions. A cushion for an automobile seat characterized by being wider than the width . 2. The automobile seat according to claim 1, wherein the polyurethane foam is used as a seat cushion, and the number of projections per the same area is smaller on the front side of the seat cushion than on the rear side. Cushions. 2. The automobile seat according to claim 1, wherein the polyurethane foam is used as a seat back, and the number of protrusions per the same area is greater on the lower side of the seat back than on the upper side. cushion. The cushion for an automobile seat according to any one of claims 1 to 3, wherein the protrusion has a shape in which a cone is placed on an upper end of a pillar body and integrated. The cushion for an automobile seat according to any one of claims 1 to 3, wherein the protrusion has a shape in which a prismatic body is mounted on an upper end of a truncated pyramid. The cushion of the automobile seat according to any one of claims 1 to 3, wherein the protrusion has a shape in which a cylindrical body is mounted on an upper end of a truncated cone.

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