Seat pad for vehicle seats and method for manufacturing the same

Abstract

The goal is to make the seat pad thinner in a more appropriate way, thereby suppressing malfunctions caused by unintended interference with other components. [Solution] In a method for manufacturing a seat pad 6P for a vehicle seat, a thin-walled portion 20 having a smaller average thickness dimension than both general portions is integrally provided between a first general portion (left front chuck portion 22) and a second general portion (back surface portion 6D) that constitute a part of the seat pad 6P, the molding process of the seat pad 6P includes a removal step in which a thick portion 51 protruding in the thickness direction of the seat pad 6P is formed at the location that will become the thin-walled portion 20 and is arranged to span between the first general portion and the second general portion, and at least a part of the thick portion 51 is removed to form the thin-walled portion 20.

Description

Technical Field

[0001] The present invention relates to a seat pad for a vehicle seat and a method for manufacturing the same.

Background Art

[0002] In this field of vehicles, there is a demand to install a vehicle seat in a vehicle interior while avoiding interference with other members. For example, in the vehicle seat disclosed in Patent Document 1, a console as another member may be adjacent to the left side portion of the seat back that serves as the backrest. Therefore, by securing a predetermined gap between the seat back and the console, it becomes possible to suppress problems caused by interference between the two members, such as the generation of abnormal noises.

[0003] Here, in the above-described seat back, a cubic airbag unit (corresponding to an airbag module) extends vertically on the left side portion facing the console. The front side, left side, and rear side of this airbag unit are covered by a foam resin pad member (corresponding to a seat pad) that forms the outer shape of the seat back. Therefore, in the above-described technology, as the dimensions of the airbag unit or the console vary or increase, it tends to become difficult to secure a gap between the seat back and the console. Therefore, as a countermeasure for securing the gap, a countermeasure of thinning the pad member portion (corresponding to the left gusset portion) that covers the left side of the airbag unit can be considered. By covering the left side of the airbag unit with a thin pad member portion in this way, it becomes easier to secure a gap between the seat back and the console.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Incidentally, when molding the pad member (seat pad) described above, the resin material is foamed in the cavity of the mold. By narrowing a part of the cavity at this time, the portion of the pad member that covers the left side of the airbag unit can be made thinner. However, in the narrowed part of the cavity, the flow of the resin material may be obstructed, hindering normal foaming, and there was a risk of unintended defects such as chipping of material in the molded seat pad. For this reason, there is a certain limit to how thin the pad member can be made, and depending on the seat configuration, it may be difficult to ensure a gap between the pad and the console. Furthermore, the harder the outer surface of the pad member becomes, the more likely it is to cause malfunctions due to unintended interference with the console, and in particular, there is a concern about the generation of abnormal noise. The present invention was devised in view of the above points, and the problem that the present invention aims to solve is to make the seat pad thinner more appropriately and to suppress malfunctions caused by unintended interference with other components. [Means for solving the problem]

[0006] As a means to solve the above problems, in the manufacturing method of a seat pad for a vehicle seat of the first invention, a thin-walled portion having a smaller average thickness dimension than both general portions is integrally provided between a first general portion and a second general portion that constitute a part of the seat pad. In this type of configuration, it is desirable to make the seat pad thinner more appropriately and to suppress defects caused by unintended interference with other members. Therefore, in the present invention, in the molding process of the seat pad, a thick portion that protrudes in the thickness direction of the seat pad is formed at the location of the thin-walled portion and arranged so as to extend between the first general portion and the second general portion. The manufacturing method then includes a removal step to remove at least a part of the thick portion to form the thin-walled portion. In the present invention, because the thick portion is molded relative to the thin-walled portion, the molding area for the thin-walled portion in the mold is widened. As a result, in the molding process of the seat pad, the stagnation of resin material at the molding area of ​​the thin-walled portion is suppressed as much as possible, and the occurrence of chipping of the seat pad can be avoided as much as possible. Furthermore, by removing the thick portion in the removal step to form the thin-walled portion, it is possible to suppress defects caused by interference with other members as much as possible.

[0007] The method for manufacturing a seat pad for a vehicle seat according to the second invention is as follows: In the method for manufacturing a seat pad for a vehicle seat according to the first invention, the thickened portion is formed on the outer surface exposed to the outside of the thin-walled portion. According to the present invention, although the thickened portion provided on the outer surface side of the thin-walled portion is removed, it is not necessary to remove the seat pad portion on the inner surface side opposite to the outside of the thin-walled portion. Therefore, for example, a reinforcing member can be integrated into the inner surface of the thin-walled portion by insert molding.

[0008] The third invention relates to a method for manufacturing a seat pad for a vehicle seat, in which, in the molding process, multiple thickened portions are formed at appropriate intervals, and each of the multiple thickened portions is a linear portion extending in the direction between the first general portion and the second general portion. In the present invention, by forming multiple thickened portions linearly at appropriate intervals, the molding area of ​​the thin-walled portion in the molding die can be expanded more appropriately, and the occurrence of material chipping in the seat pad can be more reliably avoided.

[0009] The fourth invention relates to a method for manufacturing a seat pad for a vehicle seat, which is a method for manufacturing a seat pad for a vehicle seat according to any of the first to third inventions. In this invention, the seat pad has a housing space capable of housing an airbag module, which is covered by a first general part, a second general part, and a thin-walled part. The thin-walled part is located on the outside of the housing space in the seat width direction. According to the present invention, by forming the thin-walled part on the outside of the airbag module in the seat width direction, it becomes possible to more reliably secure a gap between the airbag module and other members located on the outside of the seat width direction.

[0010] The seat pad for a vehicle seat according to the fifth invention is a seat pad for a vehicle seat in which a thin-walled portion, having a smaller average thickness dimension than both general portions, is integrally provided between a first general portion and a second general portion that constitute a part of the seat pad. Furthermore, at least a portion of the outer surface exposed to the outside of the thin-walled portion is formed to be softer than the outer surface of both general portions, extending between the first general portion and the second general portion. The thin-walled portion of the present invention is appropriately thinned by providing a flexible portion on its outer surface. With the above configuration, even if another member unintentionally interferes with the outer surface of the thin-walled portion, the flexible portion deforms due to the force applied by this other member, thereby minimizing the generation of abnormal noise due to such interference. [Effects of the Invention]

[0011] According to the first invention of the present invention, the seat pad can be made thinner more appropriately, thereby suppressing malfunctions caused by unintended interference with other components. According to the second invention, the seat pad can be made even thinner more appropriately. According to the third invention, the seat pad can be made even thinner. According to the fourth invention, the seat pad covering the airbag module can be made thinner in the appropriate places. According to the fifth invention, because the seat pad is made thinner more appropriately, malfunctions caused by unintended interference with other components can be suppressed. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic perspective view of the interior of the vehicle. [Figure 2] This is a schematic rear view of a vehicle seat and console. [Figure 3] This is a schematic cross-sectional view of the seatback showing the airbag module. [Figure 4] This is a schematic side view of the seat pad. [Figure 5] This is a schematic cross-sectional view of a mold for a seat pad. [Figure 6] This is a schematic cross-sectional view of the sheet pad after the molding process, showing the thicker sections. [Figure 7]This is a schematic side view of the sheet pad after the molding process, showing the thicker sections. [Modes for carrying out the invention]

[0013] The embodiments for carrying out the present invention will be described below with reference to Figures 1 to 7. Each figure may include arrows indicating the front-to-back, up-and-down (seat height direction), and left-to-right (seat width direction) directions of the vehicle seat as appropriate. Figure 5 also shows the up-and-down and left-to-right directions of the mold. In Figure 1, for convenience, only the right side of the vehicle interior is shown, and the vehicle seat to the right of the console, which is schematically shown with a dashed line, is shown with a solid line as a transparent view. In Figure 2, for convenience, the two members are shown as close together as possible to clarify the positional relationship between the seat back and the console, but in reality, a gap is maintained between the two members.

[0014] [Overview of the vehicle interior] First, the general layout of the passenger compartment R will be described with reference to Figures 1 and 2. A console 100 is provided in the passenger compartment R at approximately the center in the vehicle width direction. This console 100 has a predetermined height dimension and is formed to extend in the vehicle's longitudinal direction. A lid member 101 that covers the upper opening is provided at the rear of the console 100 so as to be vertically rotatable. Passenger seats 2 are positioned on both sides (left and right) of the console 100 in the vehicle width direction (for convenience, only the right passenger seat 2 is shown in each figure). The console 100 is positioned adjacent to the left side (inner side) of the right passenger seat 2, and a door (not shown) is positioned to the right side (outer side).

[0015] [Vehicle seats] In the vehicle seat 2 shown in FIG. 1, the lower part of the seat back 6 is connected to the rear part of the seat cushion 4 via a recliner (not shown). This seat back 6 is a member that serves as the backrest for the occupant and is formed in a vertically long rectangular shape when viewed from the front. In the seat back 6, as shown in FIG. 3, the seat frame 6F that forms the seat skeleton and the seat pad 6P that forms the outer shape of the seat and elastically supports the occupant are covered with a seat cover 6S that forms the seat appearance. Further, the seat cushion 4 as the seating part shown in FIG. 1 is formed in a longitudinally long rectangular shape when viewed from above, and has the same basic configuration as the seat back 6, that is, a seat cover (symbols and the like are omitted), a seat frame, and a seat pad.

[0016] Here, at the center of the front surface of the seat back 6 (seat pad 6P) shown in FIG. 1, a seating portion 6A where the occupant can sit is formed so as to extend in the vertical direction of the seat. Further, on both sides in the seat width direction (right side and left side) of the seating portion 6A, a bank portion, for example, the left bank portion 6B is provided so as to bulge upward on the seating side (in FIG. 1, for the sake of convenience, only the reference numeral corresponding to the left bank portion is shown). Then, referring to FIGS. 2 and 3, the left bank portion 6B is provided with a left cam portion 6C that constitutes the inner cam surface, and this left cam portion 6C comes to be adjacent to the console 100 described above. The left cam portion 6C is formed so as to extend in the front-rear direction of the seat, and a back surface portion 6D is continuous with the rear end portion of the left cam portion 6C. This back surface portion 6D is bent to the right side, which is the outer side, from the left cam portion 6C. As a result, on the left side portion of the seat pad 6P shown in FIG. 3, a housing space portion 10 capable of housing the airbag module 11 described later is formed so as to be surrounded by the left bank portion 6B (left cam portion 6C) and the back surface portion 6D. The housing space portion 10 is in a state where its left side and rear side are covered with the left front cam portion 22 (first general portion), the thin wall portion 20, and the back surface portion 6D (second general portion).

[0017] Referring to FIGS. 1 and 3, in the seat back 6, an airbag module 11 is disposed in a storage space 10 provided on the left side thereof. The airbag module 11 has a cubic case portion forming its outer shape extending in the seat vertical direction, and an airbag, an inflator for inflating the airbag, such as a gas supply device or a gas generant, etc. are built in this case portion. Referring to FIG. 3, the airbag module 11 is arranged in the storage space 10 in a state of being attached to the seat frame 6F, so that its front side, left side, and rear side are covered by the left side earthwork portion 6B (left side gusset portion 6C) and the back surface portion 6D. In the above-described configuration, during a vehicle collision, the airbag is discharged while inflating from the airbag module 11. And the discharged airbag will protrude toward the seat sitting side by the top side of the left side earthwork portion 6B being partially cut off, etc.

[0018] In the vehicle seat 2 shown in FIG. 1, the left side portion of the seat back 6 is arranged adjacent to the console 100 with the airbag module 11 provided therein. In this type of vehicle seat 2, from the viewpoint of suppressing the generation of abnormal noises, etc., it is desired to appropriately thin the seat pad 6P portion adjacent to the console 100, that is, the left side gusset portion 6C portion. Therefore, in this embodiment, the seat pad 6P is more appropriately thinned by the configuration (thin portion 20, flexible portion 21, thick portion 51, etc.) described later to suppress problems caused by interference with the console 100 (other members). Hereinafter, the configuration of the vehicle seat 2 will be described in detail in the order of the seat pad 6P, thin portion 20, flexible portion 21, manufacturing method (thick portion 51).

[0019] [Seat Pad] The seat pad 6P shown in FIG. 3 is a member generally rectangular in a front view following the seat back 6, and is a polyurethane foam (density: 35 kg / m 3 ~60 kg / m 3It is formed from a foamed resin such as ). This seat pad 6P has an appropriate thickness from the standpoint of elastically supporting the occupant. The outer surface of the seat pad 6P that is exposed to the outside is covered with a seat cover 6S, and the back surface opposite the outer surface is reinforced with a backing material 12. The material of this type of backing material 12 is not particularly limited, but for example, surface materials such as felt or cloth can be used for the backing material 12. On the left side of the seat pad 6P, as described above, the airbag module 11 in its storage space 10 is covered by the left side bank 6B (left frame 6C) and the back surface 6D.

[0020] [Left corner section and thin-walled section] Furthermore, the left sill portion 6C shown in Figure 1 is the seat pad 6P portion that covers the left side (outer side in the vehicle width direction) of the airbag module 11 and is positioned between the internally installed airbag module 11 and the console 100. As shown in Figure 3, a thin-walled portion 20 is formed in this left sill portion 6C at the location facing the airbag module 11. The thin-walled portion 20 is integrally formed between the left sill portion (left front sill portion 22) which is continuous with its front end and the back surface portion 6D which is continuous with the rear end of the thin-walled portion 20. That is, the left front sill portion 22 corresponds to the first general part of the present invention, and the back surface portion 6D corresponds to the second general part of the present invention. The average thickness dimension of the thin-walled portion 20 is smaller than that of the left front sill portion 22 and the back surface portion 6D (both general parts). The average thickness dimension T0 of this thin-walled section 20 is set according to the gap to be provided between the seat back 6 and the console 100, and it is preferable to take into account the size (including dimensional tolerances) of the airbag module 11 and the console 100. As an example of a method for calculating the average thickness dimension T0, one can define the dimension by the average value of the thicknesses of several randomly selected locations, for example, three or more locations, preferably five or more locations. In the above calculation method, it is desirable to exclude locations where the thickness changes excessively.

[0021] Furthermore, the thin-walled portion 20 shown in Figure 4 is formed to extend in the vertical direction of the seat with a predetermined width dimension (front-to-back dimension) when viewed from the seat width direction in a plan view. Here, the formation position and range of the thin-walled portion 20 in the left frame portion 6C can be set to a position and range in which interference with the console 100 is expected. For example, the lower side of the thin-walled portion 20 is a position in which interference with the console 100 (and the vertically rotating lid member) is expected. Therefore, the front-to-back width dimension of the lower part of the thin-walled portion 20 is made relatively large. Also, referring to Figures 3 and 4, it is desirable to set the formation range of the thin-walled portion 20 to a front-to-back and vertical range that generally covers the outer and inner surfaces 10A of the storage space portion 10. This makes it possible to appropriately secure the seat width dimension S10 of the storage space portion 10 in which the airbag module 11 should be placed, both vertically and vertically.

[0022] [Flexible part] As shown in Figures 3 and 4, the left front chuck portion 6C is provided with a number of relatively flexible flexible areas 21 at the location where the thin-walled portion 20 is formed (in Figure 4, for convenience, a reference numeral is assigned to one flexible area, and the other flexible areas are assigned a common reference numeral 21X). These multiple flexible areas 21 are relatively more flexible than the outer surface portion of the rest of the sheet pad 6P, and are therefore relatively easy to deform when external force is applied. The method for forming the flexible areas 21 is not particularly limited, but they can be formed, for example, by removing the outer surface of the molded urethane foam (details will be described later). That is, referring to Figure 3, the outer surface portion of the molded urethane foam, for example, the left front chuck portion 22 and the back surface portion 6D, is formed with a relatively high-density, hard urethane foam skin layer 23. By partially removing the skin layer 23, the flexible areas 21 can be formed with the low-density, flexible urethane foam portion inside the skin layer 23. Furthermore, in the left chuck portion 6C, multiple flexible portions 21 are formed vertically at appropriate intervals, traversing the thin-walled portion 20 in the front-to-back direction of the sheet. Each of these multiple flexible portions 21 is formed as a linear portion that is elongated in the front-to-back direction of the sheet, with a predetermined vertical width dimension. The front end (one end) of the flexible portion 21 extends and continues toward the left front chuck portion 22, which is the first general portion, and the rear end (the other end), opposite to the front end, extends and continues toward the back surface portion 6D, which is the second general portion.

[0023] Referring to Figure 4, the number, position, and vertical spacing of the multiple flexible portions 21 are not particularly limited, but it is desirable to provide at least one flexible portion 21 in a position that can face the console 100. For example, referring to Figures 2 and 4, by forming multiple flexible portions 21 in a balanced manner in the vertical direction of the sheet on the wide lower side of the thin-walled portion 20, at least one of these multiple flexible portions 21 will be positioned to face the console 100 or the lid member 101 when it rotates up and down.

[0024] [Seat pad molding mold] The sheet pad 6P shown in Figure 3 can be manufactured by going through the molding and removal processes described later. When molding the sheet pad 6P, a mold 30 having a first mold 31, a second mold 32, and an intermediate mold 33 can be used, referring to Figure 5. When the first mold 31 and the second mold 32 are closed with the intermediate mold 33 placed inside, a cavity (the first region 41, second region 42, third region 43, and narrow region 44 described later) that will be the molding space for the sheet pad 6P is formed between these molds. The direction in which the mold 30 is closed is not particularly limited, but in this embodiment, the mold is closed in the vertical direction, with the first mold 31 placed on the lower side and the second mold 32 and intermediate mold 33 placed on the upper side. Since each mold is generally symmetrical as shown in Figure 5, the details will be explained below, mainly using the left cavity portion as an example (in Figure 5, for convenience, only the left cavity portion is denoted by reference numerals).

[0025] In the mold 30 shown in Figure 5, the inner surface of the first mold 31 (first molding surface 310) and the inner surface of the second mold 32 (second molding surface 320) surrounding the cavity are shaped to resemble the outer surface shape of the seat pad. An intermediate mold 33 is in contact with the second molding surface 320 of the second mold 32, and the outer surface of this intermediate mold 33 (third molding surface 330) is shaped to resemble the inner surface shape of the seat pad. Referring to Figures 3 and 5, the seating portion 6A and the left-side ridge portion 6B of the seat pad 6P are formed by the cavity portion (first region 41) between the first mold 31 and the intermediate mold 33. The upper left and right sides of the intermediate mold 33 have inwardly recessed portions 331, and the back surface portion 6D of the seat pad 6P is formed by the cavity portion (second region 42) between these recessed portions 331 of the intermediate mold 33 and the second mold 32. Furthermore, a cavity portion (third region 43) forming the left corner portion 6C of the seat pad 6P is provided on the left end side of the first region 41. The third region 43 is located between the first region 41 and the second region 42, and is therefore in communication with both regions.

[0026] Referring to Figures 3 and 5, the third region 43 is provided with a section (narrow region 44) for forming the thin-walled portion 20 of the left front chuck portion 6C. This narrow region 44 is formed as a narrow passage (cross-sectional view) compared to other regions because the intermediate mold 33 protrudes relatively to the left. The first mold 31 that forms the narrow region 44 has multiple grooves 45 formed at appropriate positions. Specifically, referring to Figures 3 and 4, the first molding surface 310 of the first mold 31 has grooves 45 formed at locations corresponding to the formation positions of the multiple flexible portions 21 described above. Each of these multiple grooves 45 is formed as a groove that partially recesses the first molding surface 310, and has a certain depth dimension, traversing the narrow region 44 vertically. The lower ends of the multiple grooves 45 are continuous with the third region 43 for forming the left front chuck portion 22, and the upper ends of each groove 45 are continuous with the second region 42 for forming the back surface portion 6D.

[0027] Referring to Figures 5 and 7, the number, position, and spacing of the multiple grooves 45 are set from the viewpoint of suppressing the stagnation of the resin material, as will be described later, and can be appropriately selected according to the configuration of the sheet pad 6P. In the narrow region 44 where the thin-walled portion 20 is molded, it is desirable to form multiple grooves 45 in a balanced manner in areas where the stagnation of the resin material is likely to occur. For example, since the wide lower part of the thin-walled portion 20 is assumed to be the narrow region 44 where the stagnation of the resin material is likely to occur, it is desirable to form multiple grooves 45 in a balanced manner on the first molding surface 310 that molds this lower part. As will be described later, the positions of the multiple grooves 45 correspond to the positions of the thick-walled portion 51 shown in Figure 7.

[0028] [Method of manufacturing a seat pad] When molding the seat pad, the backing material 12 is pre-set in the intermediate mold 33 of the molding die 30 shown in Figure 5. Then, the resin material to be used as the molding material is supplied to the first region 41, and this resin material is foamed and filled into the cavity. As a result, as shown in Figures 5 and 6, the left front sill portion 22 (first general portion) and the back portion 6D (second general portion) are molded, and a thin-walled portion 20 is further molded between the left front sill portion 22 and the back portion 6D by the action of the narrow region 44. However, in this type of molding process, the smooth flow (foaming) of the resin material may be obstructed in the narrow region 44, which may cause molding defects such as chipping in unintended areas of the seat pad 6P, such as the back portion 6D.

[0029] Therefore, in this embodiment, referring to Figures 5 and 6, in the molding process of the seat pad 6P, the thick portion 51 that protrudes in the thickness direction of the seat pad 6P is formed in the area that will become the thin portion 20 and is positioned to extend between the left front sill portion 22 (first general portion) and the back portion 6D (second general portion). Furthermore, this manufacturing method includes a removal step in which at least a part of the thick portion 51 is removed to form the thin portion 20. According to the above manufacturing method, because the thick portion 51 is molded relative to the thin portion 20, the molding area of ​​the thin portion 20 in the mold 30 is partially widened. As a result, in the molding process of the seat pad 6P, the stagnation of resin material in the molding area (narrow region 44) of the thin portion 20 is suppressed as much as possible. Then, by removing the thick portion 51 in the removal step described later to form the thin portion 20, it becomes possible to suppress problems caused by interference with the console 100 as much as possible. The manufacturing method of the seat pad 6P will be described in more detail below.

[0030] [Molding process (formation of thick sections)] First, in the molding process, the resin material 80 supplied to the first region 41 shown in Figure 5 fills the cavity while foaming (in Figure 5, for convenience, arrows indicating the flow of the resin material are labeled with symbols indicating the resin material). At this time, the resin material 80 flows from the first region 41 through the third region 43 (narrow region 44) to the second region 42. In this embodiment, the narrow region 44 has multiple grooves 45 that are continuous, traversing the narrow region 44 and connecting the first region 41 and the second region 42. As a result, the multiple grooves 45 function as bypasses, allowing the foaming resin material 80 to flow smoothly through the narrow region 44 and reach the second region 42. With the above configuration, the action of the multiple grooves 45 makes it possible to avoid stagnation of the resin material 80 in the cavity as much as possible, and makes it possible to suppress the occurrence of unintended molding defects.

[0031] Referring to Figures 5 and 6, the sheet pad 6P is molded in a manner that minimizes material loss, and as the resin material 80 in each groove 45 hardens, multiple thickened portions 51 are formed. As shown in Figures 6 and 7, these multiple thickened portions 51 protrude to the left from the outer surface of the thin-walled portion 20, that is, in the thickness direction of the sheet pad 6P. Each of the multiple thickened portions 51 is molded to traverse the left chuck portion 6C from front to back and is positioned to span the left front chuck portion 22 (first general portion) and the back portion 6D (second general portion) (in Figure 7, for convenience, a reference numeral is assigned to one thickened portion, and a common reference numeral 51X is assigned to the other thickened portions). In the above-described manufacturing method, namely insert molding, the back material 12 set in the intermediate mold 33 is integrated with the inner surface of the sheet pad 6P during the molding of the sheet pad 6P.

[0032] As described above, in the mold 30, as shown in Figures 5 to 7, the narrow region 44 (the molding area of ​​the thin-walled portion in the mold) is partially widened by multiple grooves 45, due to the relationship in which the thick-walled portion 51 is molded relative to the thin-walled portion 20. Therefore, in the molding process, the stagnation of the resin material 80 in the narrow region 44 is suppressed as much as possible, and the occurrence of chipping of the sheet pad 6P can be avoided as much as possible. In particular, in this embodiment, by molding multiple thick-walled portions 51 linearly at appropriate intervals, the narrow region 44 can be widened more appropriately, and the occurrence of chipping of the sheet pad 6P can be avoided more reliably.

[0033] [Removal process] Next, in the removal process, referring to Figures 3 and 6, at least a portion of the thick portion 51 is removed to form the thin portion 20. The method for removing the thick portion 51 is not particularly limited, but examples of physical removal methods include slicing and cutting, and cutting blades and vibrating blades can be used as appropriate. Examples of thermal removal methods include laser (hot wire) processing and wire electrical discharge machining. In the removal process, the thick portion 51 is removed together with the skin layer 23, so that the lower-density urethane foam inside the skin layer 23 is exposed on the outer surface after removal. As a result, a flexible portion 21 is formed on the outer surface of the left corner portion 6C so as to traverse the thin portion 20 from front to back. Furthermore, by forming the thick portion 51 on the outer surface of the sheet pad 6P, it is not necessary to remove the inner surface of the sheet pad 6P after the removal process, so the back material 12 integrated with the inner surface can be left as is.

[0034] In the seat pad 6P, as shown in Figure 7, multiple thickened sections 51 are formed vertically at appropriate intervals relative to the thinned section 20, so that the original thinned section 20 is formed between adjacent thickened sections 51. Therefore, by removing the thickened sections 51 using the thinned section 20 between adjacent thickened sections 51 as a guide, these thickened sections 51 can be removed appropriately, for example, without any waste. As a result, referring to Figures 3 and 6, the outer surface of the flexible section 21 formed in the area where the thickened section 51 was removed becomes approximately flush with the outer surface of the thinned section 20, with the skin layer 23 removed. By making the thinned section 20 and the flexible section 21 flush in this way, a part of the seat cover 6S does not bulge unnaturally, and highlights are less likely to occur, thus contributing to ensuring a superior appearance of the seat. Furthermore, if interference with other members and appearance can be ensured, only a part of the multiple thickened sections 51, for example, only the thickened section near the lower end, may be removed, and the amount of removal can be adjusted for each thickened section 51.

[0035] [Installation of vehicle seats inside the vehicle interior] Referring to Figures 1 and 2, the vehicle seat 2 is installed on the right side in the vehicle width direction of the console 100, as described above. As a result, the left chuck portion 6C of the seat back 6 is positioned adjacent to the console 100 with the airbag module 11 installed inside. In this type of configuration, the more variation there is in the dimensions of the airbag module 11 or the console 100, or the larger they become, the more difficult it may be to secure a gap between the seat back 6 and the console 100. Therefore, in this embodiment, the left chuck portion 6C is appropriately thinned by forming a thin-walled portion 20 with a desired average thickness dimension, as shown in Figures 2 and 4. As a result, even when the airbag module 11 is installed inside the left side of the seat back 6, an appropriate gap can be easily provided between the seat back 6 and the console 100. With the above-described configuration, the function of the appropriately formed thin-walled portion 20 makes it possible to avoid unintended interference between the seat back 6 and the console 100 as much as possible, and it is possible to suppress the generation of abnormal noise (an example of a malfunction) due to interference between the two members. Furthermore, referring to Figure 2, by providing a thin-walled portion 20 extending vertically from the left frame portion 6C, interference between the lid member 101, which rotates vertically on the console 100, and the seat back 6 can be avoided as much as possible. As a result, malfunctions of the lid member 101 caused by interference (an example of a problem) are avoided, and the lid member 101 can be smoothly rotated upward to open or downward to close. With the above configuration, an airbag module 11 can be installed internally on the left side (inner side) of the seat back 6 according to customer and market needs, and it is also possible to accommodate larger consoles 100.

[0036] Furthermore, referring to Figures 2 to 4, flexible portions 21 are provided at appropriate positions on the outer surface of the left frame portion 6C. Therefore, even if the seat back 6 and the console 100 unintentionally interfere with each other, the flexible portion 21, upon which an external force is applied from the console 100, will bend and deform appropriately, thereby suppressing the generation of abnormal noise. Moreover, since the flexible portion 21 is provided on the left frame portion 6C so as to extend in the front-rear direction of the seat (the direction extending across both general parts), it is possible to suppress the generation of abnormal noise caused by contact with the console 100 over a wide area of ​​the left frame portion 6C.

[0037] As explained above, in this embodiment, since the thick portion 51 is formed relative to the thin portion 20, the molding area (narrow region 44) of the thin portion 20 in the mold 30 is widened. Therefore, in the molding process of the seat pad 6P, the stagnation of resin material in the molding area of ​​the thin portion 20 is suppressed as much as possible, and the occurrence of chipping of the seat pad 6P can be avoided as much as possible. Furthermore, by removing the thick portion 51 in the removal process to form the thin portion 20, it is possible to suppress defects caused by interference with the console 100 (other members) as much as possible. Therefore, according to this embodiment, the seat pad 6P can be made thinner more appropriately, and defects caused by unintended interference with other members can be suppressed. Furthermore, with the above configuration, even if another member unintentionally interferes with the outer surface of the thin portion 20, the flexible portion 21 will deform due to the force applied by this other member, so the generation of abnormal noise due to such interference can be suppressed as much as possible.

[0038] Furthermore, according to this embodiment, although the thickened portion 51 provided on the outer surface side of the thin-walled portion 20 is removed, it is not necessary to remove the sheet pad 6P portion on the inner surface side opposite to the outer surface of the thin-walled portion 20. For this reason, for example, the backing material 12 (reinforcement member) can be integrated into the inner surface of the thin-walled portion 20 by insert molding. In addition, in this embodiment, by forming multiple thickened portions 51 linearly at appropriate intervals, the narrow area 44 can be expanded more appropriately, and the occurrence of material chipping of the sheet pad 6P can be more reliably avoided. Furthermore, according to this embodiment, by forming the thin-walled portion 20 on the outer side in the sheet width direction of the airbag module 11, a gap can be more reliably secured with other members arranged on the outer side in the sheet width direction.

[0039] The seat pad for a vehicle seat and its manufacturing method according to this embodiment are not limited to the embodiments described above, and various other embodiments are possible. For example, the thickened portion formed by the groove and the flexible portion formed by the removal process can be provided linearly or planarly at appropriate positions in the thin portion. In addition to the lower part of the thin portion shown in Figure 7, the thickened portion can also be provided in the upper part of the thin portion, and at least a portion of the thickened portion in the lower and upper parts can be removed. The thickened portion (groove) can be formed linearly or curved, and the protruding dimension of the thickened portion (depth dimension of the groove) may be uniform in the front-to-back direction, etc., or may vary in part. The two general portions and the thin portion can be formed so as to be aligned in the front-to-back direction of the seat, as well as in the width direction or vertical direction of the seat. The direction in which the thickened portion (flexible portion) extends is set according to the direction in which the two general portions and the thin portion are aligned. In addition to the backing material, various members capable of reinforcing the seat pad can be used as reinforcing members. Furthermore, if the reinforcing member (backing material) of the seat pad is not integrated, or if the reinforcing member is added later, the thickened portion can be formed on at least one of the inner or outer surfaces of the seat pad.

[0040] Furthermore, the position of the thin-walled section can be appropriately changed according to the seat configuration, and can be provided not only on either the left or right frame of the seat back, but also at an appropriate position on the seat back or seat cushion. Other components that may interfere with the vehicle seat include various components installed inside the vehicle, such as consoles, and components that make up the vehicle, such as doors. Seat accessories such as shield members adjacent to the seat pad can also be considered other components. For example, when a shield member is placed on the outside of the seat cushion in the seat width direction, a thin-walled section can be provided on the seat pad portion of the outer part of the seat cushion (right or left side) to avoid unintended interference with the shield member. The configuration of this embodiment can be applied to vehicle seats in general, such as those in cars, aircraft, trains, and ships. [Explanation of Symbols]

[0041] 2. Vehicle seats 4 seat cushions 6 Seatback 6S Seat Covers 6F Seat Frame 6P Seat Pad 6A Seating area 6B Left side of the embankment 6C Left side panel 6D Back surface (second general part of the present invention) 10. Containment space 11 Airbag Module 12 Backing material 20 Thin-walled section 21 Flexible parts 22 Left front gusset area (first general part of the present invention) 23 Skin Layers 30 mold 31 Type 1 32 Type 2 33 Intermediate type 41 First area 42 Second area 43 Third area 44 Narrow area 45 Groove 51 Thick part 80 Resin materials 100 Consoles 101 Lid member 310 First molding surface 320 Second molding surface 330 Third molding surface 331 Recessed area R (Inside the vehicle)

Claims

1. In a method for manufacturing a seat pad for a vehicle seat, a thin-walled portion having a smaller average thickness than both general portions is integrally provided between a first general portion and a second general portion that constitute a part of the seat pad, In the molding process of the sheet pad, the thick portion that protrudes in the thickness direction of the sheet pad is formed in the thin portion and is arranged to extend between the first general portion and the second general portion, A method for manufacturing a seat pad for a vehicle seat, comprising a removal step of removing at least a portion of the thick portion to form the thin portion.

2. The method for manufacturing a seat pad for a vehicle seat according to claim 1, wherein the thickened portion is formed on the outer surface exposed to the outside of the thinned portion.

3. A method for manufacturing a seat pad for a vehicle seat according to claim 1, wherein, in the molding step, a plurality of the thickened portions are formed at appropriate intervals, and each of the plurality of thickened portions is a linear portion extending in a direction between the first general portion and the second general portion.

4. A method for manufacturing a seat pad for a vehicle seat according to any one of claims 1 to 3, wherein the seat pad has a housing space capable of housing an airbag module, which is covered by the first general portion, the second general portion, and the thin portion, and the thin portion is arranged on the outside of the housing space in the seat width direction.

5. In a seat pad for a vehicle seat, a thin-walled section having a smaller average thickness than both general sections is integrally provided between a first general section and a second general section that constitute a part of the seat pad, A seat pad for a vehicle seat, wherein at least a portion of the outer surface exposed to the outside of the thin-walled portion is formed such that a flexible portion, softer than the outer surfaces of both general portions, extends between the first general portion and the second general portion.

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