JP6721164B2 - Seat back and manufacturing method thereof - Google Patents

Description

The present invention relates to a seatback including a backrest portion made of a foamed resin member and an upper portion made of a foamed resin member and located above the backrest portion, and a method for manufacturing the seatback.

For example, as shown in FIG. 11, a vehicle seat 10 includes a seat seat 12 on which an occupant sits and a seat back 14 on which the occupant rests his back. Since the seat 10 shown in FIG. 11 is in a state before the makeup skin sheet is attached, the seat seat 12 and the seat back 14 are exposed with the pad itself formed of foamed resin such as urethane. ing. Since the present invention relates to the seat back 14 in the seat 10 shown in FIG. 11, the seat back 14 may be referred to as a seat back pad in the present specification. Further, although FIG. 11 shows the pad 14 of the seat back used for the seat 10 for the vehicle, the present invention is not limited to the seat back for the vehicle.

Japanese Patent No. 5203691

As shown in FIG. 12, the backrest portion 16 is configured such that the hardness of the foamed resin forming the backrest central portion 16a is set to be soft and the left and right side portions 16b, 16b adjacent to each other with the backrest central portion 16a sandwiched therebetween are provided. By setting the hardness of the foamed resin to be formed to be relatively high, the hardness of both parts 16a and 16b is made different. Further, as shown in FIG. 11, the pad 14 of the seat back is provided with a backrest portion 16 which serves as a main body portion, and an upper portion 18 which is located above the backrest portion 16 and supports the neck and shoulders of a seated occupant. Is divided into In order to support the back of the occupant softly, the backrest 16 sets the hardness of the foamed resin as the base material to a low level, while the upper portion 18 firmly supports the occupant's neck and shoulders. In order to hold the body stably, the hardness of the foamed resin as the base material is also set to be high.

As described above, the hardness of the foamed resin used for the backrest portion 16 and the upper portion 18 may be different. Therefore, as shown in FIG. 12, when the seatback 14 is manufactured by integrally foam-molding the backrest portion 16 and the upper portion 18 with one foaming mold (not shown), a foaming mold not shown Is provided with a partition (weir) for partitioning the molding portion of the backrest portion 16 and the molding portion of the upper portion 18, and foaming resin raw materials exhibiting different hardness during foaming and solidification are supplied to the corresponding molding portions. I am trying to let you. However, in this case, as is clear from FIG. 12, the foamed pad 14 of the seat back has a predetermined width as a trace of the partition (weir) at the boundary between the backrest portion 16 and the upper portion 18. Thus, the groove portion 20 having a depth is formed. When the groove portion 20 is present in the seat back 14, when the seat back 14 is covered with a skin sheet in a later step, the groove portion 20 causes a highlight line or the like at a portion corresponding to the skin sheet to impair the appearance. There are drawbacks.

Therefore, as shown in FIG. 13, it has been proposed to manufacture the backrest portion 16 and the upper portion 18 as separate bodies by foam-molding each in a separate foaming type, and then to join the backrest portion 16 and the upper portion 18. ing. That is, the seat back 14 shown in FIG. 14 is obtained by applying the adhesive 22 to both or either of the joint surfaces of the backrest portion 16 and the upper portion 18 and adhering the members 16 and 18 together. .. The adhesive 22 is selected to be a type that does not react with either the foamed resin member forming the backrest portion 16 or the foamed resin member forming the upper portion 18. In this case, since the backrest portion 16 and the upper portion 18 are adhered by the adhesive 22 and the groove portion 20 shown in FIG. 12 does not exist, a situation occurs that the outer appearance is impaired after the outer skin sheet is covered. Absent. However, variations in adhesion due to the adhesive 22 may deteriorate the finish of the joint. Further, as shown in FIG. 15, for example, when a strong force is applied to the upper portion 18 due to the influence of the release agent used for facilitating the demolding from the foaming mold, the backrest portion 16 and the upper portion 18 are separated from each other. May peel off from the adhesive surface to form a peeling opening 17.

The present invention has been proposed in order to solve the above-mentioned drawbacks of the prior art, and after joining the upper part manufactured as a separate body and the non-woven fabric, the back part is foam-molded to the upper part via the non-woven fabric. By joining, the strong joining of both members is achieved.

In order to solve the above problems and achieve an intended object, the invention according to claim 1 comprises a backrest portion made of a foamed resin member, and a foamed resin member having a hardness different from that of the foamed resin member, and the backrest portion. In the seat back consisting of the upper part joined to
The gist is that the backrest portion and the upper portion are joined together via a nonwoven fabric having naps on both surfaces.
According to the invention of claim 1, the upper portion manufactured as a separate body and the backrest portion that is subsequently foam-molded are strongly bonded via the non-woven fabric and are not easily peeled off.

In the invention according to claim 2, the nonwoven fabric sandwiches the intermediate nonwoven fabric layer from both sides and an intermediate nonwoven fabric layer for preventing permeation of the foamed resin raw material during foam molding of the backrest portion and the upper portion, and at the same time, the foamed resin raw material is provided. The gist of the present invention is to have a three-layer structure including the outer nonwoven fabric layer having the naps that penetrate into it.

In the invention according to claim 3, the non-woven fabric is composed of three layers including an intermediate non-woven fabric layer made of polypropylene or PET fiber and an outer non-woven fabric layer having naps sandwiching both sides of the intermediate non-woven fabric layer. It is a gist that PET fiber cotton is laminated on both sides of a spunbond non-woven fabric sheet constituting a layer by a needle punching method to be laminated.

According to the inventions according to claims 2 and 3, the non-woven fabric is composed of an intermediate non-woven fabric layer and an outer non-woven fabric layer having naps sandwiching the intervening non-woven fabric layer from both sides, and fluffed naps on both sides of the non-woven fabric are the backrest part. Further, since both of them enter the foamed resin in the upper portion, both members are firmly joined.

In order to solve the above problems and achieve an intended object, the invention according to claim 4 is characterized in that after setting a nonwoven fabric having naps on both surfaces at a predetermined position of the first foaming mold, the first foaming mold is set to the first foaming mold. Supplying a first foamed resin raw material and foaming it to form an upper portion of a desired shape in which the non-woven fabric is joined to an end portion;
The upper part, which is removed from the first foaming mold and joined with the nonwoven fabric, is set at a predetermined position of the second foaming mold, and the open surface of the nonwoven fabric is foamed in the second foaming mold. A step of directing to the supply site of the resin raw material,
By supplying the second foaming resin raw material exhibiting a hardness different from the hardness expressed by the first foaming resin raw material forming the upper portion to the second foaming mold to cause foaming, The gist is that it comprises a step of forming a seat back in which the backrest portion is joined via the non-woven fabric.
According to the invention of claim 4, the seat back according to claim 1 can be efficiently manufactured.

According to the present invention, the upper portion, which is manufactured as a separate body, is joined to the backrest portion via the non-woven fabric, so that strong joining of both members is achieved.

It is explanatory drawing which shows the seat back which concerns on the Example of this invention, Comprising: The backrest part and the upper part are joined through the nonwoven fabric. It is an end view which shows the state which joined the nonwoven fabric to the end surface of an upper part. FIG. 3 is an end view showing a state where the nonwoven fabric has a specific shape in the upper portion shown in FIG. 2. FIG. 3 is an explanatory perspective view showing that the nonwoven fabric used in FIG. 1 has a three-layer structure. FIG. 3 is a cross-sectional view of a first foaming mold in which the upper part is foam-molded, showing a state in which the upper mold and the middle mold are opened with respect to the lower mold, and a nonwoven fabric is set at a required position in the cavity of the lower mold. In the first foaming mold shown in FIG. 5, the lower mold is closed by the upper mold and the middle mold to foam the first foaming resin raw material in the cavity, thereby molding the upper part in which the non-woven fabric is bonded to one end surface. It shows the state. It is a schematic plan view of the 1st foaming type shown in FIG. FIG. 6 is a cross-sectional view of a second foaming mold for manufacturing a seat back in which the backrest is foamed and joined to the upper part, wherein the upper mold and the middle mold are opened with respect to the lower mold, and the molded upper part is set in the middle mold. In addition, the second foamed resin material is being supplied to the cavity of the lower mold. In the second foaming mold shown in FIG. 8, by closing the lower mold with the upper mold and the middle mold to foam the second foamed resin raw material in the cavity, the seat back in which the backrest part and the upper part are joined by the non-woven fabric. It shows the molded state. FIG. 9 is a cross-sectional view showing a state in which the upper mold and the middle mold are opened after the molding of the seat back is completed in the second foaming mold shown in FIG. 8, and the upper part held by the middle mold is joined with the nonwoven fabric. The backrest is also held in the medium size. 1 is a schematic perspective view of a vehicle seat including a seat and a seat back. FIG. 1 is a plan view of a general seat back in which a backrest portion and an upper portion are integrally foam-molded. It is a top view which shows a seat back in a separated state, and shows the state before joining an upper part to a backrest part with an adhesive agent. The seat back shown in FIG. 13 shows a state in which the upper portion and the backrest portion are bonded together. It is a partial side view of the seat back in which the upper portion is joined to the backrest portion, and shows a state in which the joined portions of both members are separated.

Next, preferred embodiments of the present invention will be described with reference to the drawings. The basic structure of the seat back according to the embodiment is the same as that described with reference to FIGS. 11 to 15. Therefore, the same reference numerals are given to the already-explained members, and the description thereof will be omitted. Further, as described above, the seat back of the vehicle seat will be described with the seat back in mind, but the seat back and the manufacturing method thereof according to the present invention are not limited to the use for the vehicle, and for consumer use (for example, It can also be widely used for office and home use.

As shown in FIGS. 1A and 1B, the seat back 14 according to the embodiment includes a backrest portion 16 made of a foam resin member such as urethane, and a foam resin member having a hardness different from that of the foam resin member. The upper portion 18 is joined to the upper portion 18 via a nonwoven fabric 24 having naps on both sides. That is, as described later with reference to FIGS. 5 and 6, the upper portion 18 is foam-molded by the first foaming mold 26 in which the nonwoven fabric 24 is set, so that one end surface is The non-woven fabric 24 is joined to. In FIG. 1(2), when the backrest portion 16 and the upper portion 18 are joined via the nonwoven fabric 24, the state in which the raised fabric of the nonwoven fabric 24 enters the backrest portion 16 and the upper portion 18 is circled. It is shown in an enlarged view. Here, the non-woven fabric 24 preferably has a three-layer structure shown in FIG. 4, and has an intermediate non-woven fabric layer 24a which prevents the foamed resin raw material from permeating, and an outer non-woven fabric having naps sandwiching the intermediate non-woven fabric layer 24a from both sides. The layers 24b and 24b. The outer nonwoven fabric layer 24b having the nap has a nap that is fluffed at least on the side not in contact with the intermediate non-woven fabric layer 24a, and when the foamed resin raw material foams, the foamed resin enters after the nap occurs. Is solidifying. In addition, the outer nonwoven fabric layer 24b is configured such that the foamed resin raw material penetrates when the foamed resin raw material foams. That is, since the non-woven fabric 24 having the three-layer structure has naps on both sides thereof, when the upper portion 18 is independently foam-molded by the first foaming mold 26, the first foaming is performed. As a result of the raised fibers on one surface of the non-woven fabric 24 set in the mold 26 entering the foamed resin raw material, the non-woven fabric 24 is strongly bonded to one end surface of the upper portion 18.

The specific configuration of the non-woven fabric 24 shown in FIG. 4 will be described. The intermediate non-woven fabric layer 24a of the non-woven fabric 24 uses a non-woven fabric sheet based on synthetic resin fibers. As will be described later with reference to FIGS. 6 and 9, the intermediate non-woven fabric layer 24a is formed by foaming a foamed resin raw material in a closed foaming mold from one side of the non-woven fabric 24 to the other side thereof. Permeate and harden the nap of the outer nonwoven fabric layer 24b located on the other side. Therefore, as the intermediate nonwoven fabric layer 24a, for example, a nonwoven fabric sheet formed by eluting a polypropylene raw material melted by a spunbond method from a nozzle to form continuous long fibers into a web and pressing the fibers together is used. Then, PET (polyethylene terephthalate) fiber cotton is placed on both sides of this non-woven fabric sheet, and these are pierced with a large number of needles by a needle punching method, whereby the PET fibers are intricately entangled with each other to form the three-layer non-woven fabric. It can be 24.

FIG. 2 shows a state in which a nonwoven fabric 24 is joined to the open end surface of the upper portion 18 shown in FIG. 1(1), and the nonwoven fabric 24 exists over the entire open end surface of the upper portion 18. As shown in FIG. 2, when the non-woven fabric 24 is positioned over the entire open end surface of the upper portion 18, there is an advantage that the upper portion 18 and the backrest portion 16 are joined very strongly, but the obtained molding is obtained. In some cases, the sense of rigidity of the joint region between the two members 18 and 16 in the seat back 14, which is a product, becomes too large. In such a case, as shown in FIG. 3, the nonwoven fabric 24 is formed, for example, in the shape of a strip and has a curved portion at the tip, and the nonwoven fabric 24 is joined to the open end surface of the upper portion 18 to develop It is recommended to adjust the stiffness that is applied.

(About manufacturing method)
Next, a method of manufacturing the seat back according to the embodiment will be described. The outline of this manufacturing method is as follows: (1) a step of manufacturing the upper part 18 in which the nonwoven fabric 24 is joined to one end face thereof with the first foaming mold 26 in advance, and (2) the separately manufactured upper part 18 Is set in the second foaming mold 28, and the open surface of the non-woven fabric 24 joined to the upper portion 18 is directed toward the foamed resin material supply side in the cavity of the second foaming mold 28. Then, the step of molding the seat back 14 in which the upper portion 18 and the backrest portion 16 are joined via the nonwoven fabric 24 is performed.

(Process by the first foaming mold)
5 and 6 show a first foaming mold 26 for foam-molding the upper portion 18 in which the nonwoven fabric 24 is joined to one end portion. The first foaming mold 26 includes a lower mold 30, an upper mold 34 rotatably supported by a hinge 32 (see FIG. 7) on the lower mold 30, and an upper mold 34 as shown in a plan view of FIG. The upper mold 34 includes a middle mold 38 which is located in a bay portion and is pivotally supported by the hinge 36 so as to be openable and closable with respect to the lower mold 30. Then, as shown in FIG. 6, when the upper mold 34 and the middle mold 38 are closed with respect to the lower mold 30, the cavity 40 formed in the first foam mold 26 is provided outside the upper portion 18. It has an internal contour shape that follows the contour. The upper mold 34 and the middle mold 38 may be opened and closed in synchronization. However, when the upper mold 34 is opened prior to the middle mold 38, the middle mold 38 is closed when the upper mold 34 is closed. It may be closed prior to the upper mold 34.

As shown in FIG. 5, with the upper mold 34 and the middle mold 38 open to the lower mold 30, the non-woven fabric 24 is inserted into the cavity 40 of the lower mold 30, and the non-woven fabric 24 is placed in the predetermined cavity 40. Lock in position. As a means for fixing the non-woven fabric 24 in the cavity 40, for example, an appropriate number of magnet pieces (not shown) are attached to the important points of the non-woven fabric 24, and the non-woven fabric 24 is magnetically attracted to the inner surface of the cavity 40 by the magnet pieces. It is possible. In this way, after setting the nonwoven fabric 24 in the cavity 40 of the lower mold 30, the first foaming resin material A for foam-molding the upper portion 18 is supplied from the nozzle 52 to the cavity 40.

Next, as shown in FIG. 6, the upper mold 34 and the middle mold 38 of the first foaming mold 26 are closed with respect to the lower mold 30. Since the first foaming mold 26 is maintained at a predetermined temperature and pressure, the first foaming resin raw material A supplied to the cavity 40 starts foaming and the inner contour of the cavity 40 is started. And forming the upper portion 18 having an outer contour shape conforming to. At this time, as described above, the fluffed raised hairs are present on the surface of the non-woven fabric 24 set in the lower mold 30 in advance toward the cavity 40 side. The foamed resin raw material A is solidified with the raised fibers. That is, in the upper portion 18 formed by foaming the first foamed resin raw material A, the raised portion of the non-woven fabric 24 is inserted into the foamed portion at the portion in contact with the non-woven fabric 24. In addition, the first foamed resin raw material A is impregnated and cured at the portion of the nonwoven fabric 24 that contacts the upper portion 18. Therefore, both members 18 and 24 are joined very strongly.

When the curing time required for the first foaming resin raw material A has elapsed, the upper mold 34 of the first foaming mold 26 is first opened, and then the middle mold 38 is opened. By opening the middle mold 38, the foam-molded upper portion 18 is released from the lower mold 30 while being held by the middle mold 38. As described above, the non-woven fabric 24 is joined to one end of the demolded upper portion 18, and the raised fabric is exposed on the open surface of the non-woven fabric 24. As described with reference to FIG. 6, the first foamed resin raw material A penetrates into one side of the nonwoven fabric 24, but the first foamed resin raw material A spreads onto the other side of the nonwoven fabric 24. Is not leaching. This is because the non-woven fabric 24 has the intermediate non-woven fabric layer 24a for preventing the permeation of the first foamed resin raw material A.

(Process by the second foaming mold)
Next, the process of manufacturing the seatback 14 by joining the upper portion 18 molded by the first foaming mold 26 to the backrest portion 16 via the nonwoven fabric 24 as described above will be described with reference to FIGS. Description will be given with reference to the second foaming mold 28 shown. That is, as shown in FIGS. 8 to 10, the second foaming mold 28 includes a lower mold 44 and an upper mold 46 pivotably supported on the lower mold 44 via a hinge (not shown). , A middle mold 50 pivotally supported on the lower mold 44 via a hinge 48 so as to be openable and closable. The basic structure of the second foaming mold 28 is almost the same as that of the first foaming mold 26. However, the inner contour shape of the cavity 42 of the second foaming mold 28 formed when the mold is clamped is the outer contour shape of the seat back 14 in which the backrest portion 16 and the upper portion 18 are joined by the nonwoven fabric 24. It is matched.

As shown in FIG. 8, in the second foaming mold 28, the upper mold 46 and the middle mold 50 are opened in an inclined state with respect to the lower mold 44. At this time, the upper mold 46 is opened at a larger angle than the middle mold 50. In this state, the upper portion 18 foam-molded in the previous step is inserted and held in the protruding tip portion 50a of the middle die 50. At this time, the non-woven fabric 24 joined to the upper portion 18 is located below the protruding tip portion 50a of the middle die 50, as can be seen from FIG. 8, and the middle die 50 is closed as will be described later with reference to FIG. When this is done, the nonwoven fabric 24 is oriented inside the cavity 42 of the lower mold 44. Further, in the opened state of the second foaming mold 28 shown in FIG. 8, a predetermined amount of the second foaming resin raw material B is supplied from the nozzle 54 to the cavity 42.

Next, as shown in FIG. 9, the middle die 50 holding the upper portion 18 is closed with respect to the lower die 44, and then the upper die 46 is closed with respect to the lower die 44 with a time lag. To do. At this time, a part of the cavity 42 of the upper mold 46 is occupied by a part of the upper portion 18 held by the middle mold 50. When the second foaming mold 28 is completely closed, the second foaming resin raw material B starts foaming in the cavity 42 kept at a predetermined temperature and pressure, and in the cavity 42, the upper part The backrest portion 16 is formed in a space not occupied by the backrest portion 18. At this time, since the raised surface due to the above-mentioned fluffing is present on the open surface of the non-woven fabric 24 joined to the upper portion 18, the raised fabric of the non-woven fabric 24 is added to the second foamed resin raw material B being foamed. Goes in. Further, the second foamed resin raw material B also penetrates into the portion of the nonwoven fabric 24 that comes into contact with the backrest portion 16 and is cured. Therefore, when the second foamed resin material B is foamed and solidified to form the backrest portion 16, the backrest portion 16 is strongly bonded to the nonwoven fabric 24. That is, the backrest portion 16 and the upper portion 18, which are foam-molded in the cavity 42, are strongly bonded via the nonwoven fabric 24.

Next, when the predetermined curing time required for the second foaming resin raw material B has elapsed, as shown in FIG. 10, the upper mold 46 and the middle mold 50 of the second foaming mold 28 are set to the lower mold 44. Open to. Then, the seat back 14 including the backrest portion 16 and the upper portion 18 that are integrally foam-molded is attached to the protruding tip portion 50a of the middle die 50. Then, by removing the molded product including the backrest portion 16 and the upper portion 18 from the middle mold 50, the seat back 14 as a pad shown in FIG. 1 is obtained.

14 seat back (seat back pad), 16 backrest,
16a central part of backrest, 16b side part 18 upper part, 24 non-woven fabric,
24a middle non-woven fabric layer, 24b outer non-woven fabric layer, 26 first foaming mold,
28 Second foaming type

Claims (4)

In a seat back composed of a backrest part made of a foamed resin member, and a foamed resin member having a hardness different from that of the foamed resin member, and an upper part joined to the backrest part,
The seat back, wherein the backrest portion and the upper portion are joined via a nonwoven fabric having raised hairs on both sides. The non-woven fabric includes an intermediate non-woven fabric layer for preventing permeation of a foamed resin raw material during foam molding of the backrest part and an upper part, and an outer non-woven fabric layer having the raised fibers that sandwich the intermediate non-woven fabric layer from both sides and enter the foamed resin raw material. The seat back according to claim 1, which has a three-layer structure of The non-woven fabric is composed of three layers including an intermediate non-woven fabric layer made of polypropylene or PET fiber and an outer non-woven fabric layer having naps sandwiching both sides of the intermediate non-woven fabric layer. The seat back according to claim 1 or 2, wherein PET fiber cotton is laminated on both sides of the nonwoven fabric sheet by a needle punching method to be laminated. After setting a non-woven fabric having naps on both sides at a predetermined position of the first foaming mold, the first foaming resin raw material is supplied to the first foaming mold to foam the non-woven fabric, and the non-woven fabric is joined to the end of the required shape Forming an upper part of
The upper part, which is removed from the first foaming mold and joined with the nonwoven fabric, is set at a predetermined position of the second foaming mold, and the open surface of the nonwoven fabric is foamed in the second foaming mold. A step of directing to the supply site of the resin raw material,
By supplying the second foaming resin raw material exhibiting a hardness different from the hardness expressed by the first foaming resin raw material forming the upper portion to the second foaming mold to cause foaming, A method of manufacturing a seat back, comprising a step of forming a seat back in which a backrest portion is joined via the non-woven fabric.

Images