WO2004034853A1

WO2004034853A1 - Cushion pad for seat, and method of manufacturing the cushion pad

Info

Publication number: WO2004034853A1
Application number: PCT/JP2003/001195
Authority: WO
Inventors: Masanobu Banno
Original assignee: Toyo Tire & Rubber Co., Ltd.
Priority date: 2002-10-18
Filing date: 2003-02-05
Publication date: 2004-04-29
Also published as: AU2003207238A1; JP4134039B2; JPWO2004034853A1

Abstract

A cushion pad for seat and a method of manufacturing the cushion pad, the cushion pad (A) of stacked structure capable of providing a high freedom degree for the distribution of thicknesses of foam layers and the setting of depth of slits, forming the slits in deep grooves, and sufficiently assuring the tolerance for burying locking members such as slit wire therein wherein the slits (3) are formed in the first foam layer (1) as a front layer and locking members (5) are buried near the groove bottoms thereof; the method of manufacturing the cushion pad comprising the steps of forming the rear surface of the slit formed portion of the first foam layer (1) so as to form a swelling on a second foam layer (2) and burying the locking members (5) in the second foam layer (2) with a burying tolerance of a specified value or more provided thereto by swelled portions (7).

Description

Description Sheet cushion pad for sheet and manufacturing method thereof [Technical field]

The present invention mainly relates to a cushion pad for a seat of an automobile or the like and a method for manufacturing the same.

(Background technology)

For example, an automobile seat is configured by covering a cushion pad made of a resin foam layer such as urethane foam with a skin material such as cloth.

In this type of cushion pad, for example, two types of resin foam layers such as urethane foam with different hardness are interposed directly or with a thin sheet-like reinforcement layer in order to improve sitting comfort and riding comfort. A pad having a laminated structure in which the layers are stacked by using the same has been proposed.

The cushion pad having the laminated structure generally includes a lower mold for molding the pad surface, a first upper mold for the surface layer and a second upper mold for the back layer which can be opened and closed with respect to the lower mold. Using the provided mold, first form the first foam layer as the surface layer, and then form and laminate the second foam layer as the back layer (lower layer) on the side to be attached to the support material (For example, Japanese Patent Application Laid-Open Nos. Sho 62-24091 and 63-120610). In such a cushion pad, as means for attaching the skin material, a slit is formed on the cushion pad, and a rod-shaped locking member called a slit wire is provided near the groove bottom of the slit. Is buried, and the locking means attached to the skin material is locked and fixed to the locking member, whereby the edge or the stitched portion of the sewn skin material is fixed. Part of the slit It is common to put it in between.

By the way, in the above-mentioned cushion pad having a laminated structure, a slit for attaching a skin material and a locking member such as a wire are provided on the first foam layer serving as a surface layer. For example, as shown in FIG. 11, a skin-mounting thread is provided between a center portion 41 a such as a seat portion on the surface of the first foam layer 41 and both side portions 41 b and 41 b. The slit 43 is formed, and the locking member 45 is embedded near the groove bottom 43 a of the slit 43.

In this embedding structure, the embedding allowance of the locking member 45 is at least 10 mm between the locking member 45 and the joint surface with the second foam layer 42, and the groove bottom 4 of the slit 43 is formed. At least 5 mm is required between 3a. In addition, it is necessary to ensure fluidity in the mold during molding and to ensure uniformity of the foam layer. Therefore, the depth of the slit 43 is limited by the thickness of the first foam layer 41.

For example, as shown in FIG. 12, the first foam layer 41 and the second foam layer 42 are joined and laminated on a relatively flat surface, and the first foam layer 41 When the locking member 45 is embedded in the first foam layer 41 when the thickness t is 25 mm, the joining surface 46 of the foam layer 41 and the second foam layer 42 is formed. In order to secure at least 10 mm as the embedding allowance c of the locking member 45 against the groove and at least 5 mm as the embedding allowance a of the locking member 45 with respect to the groove bottom 43 a, The depth b of the slit 43 becomes 10 mm. Therefore, when the thickness t of the first foam layer 41 is reduced, the slit of the deep groove cannot be set.

On the other hand, users are strongly demanding that the slit 43 have a deep groove feeling in order to improve the external appearance of the sheet, but the slit depth is limited as described above. As a result, it is not possible to meet the demand. The present invention has been made in view of the above, and has a high degree of freedom in setting the thickness distribution of each foam layer and the depth of a slit for attaching a skin material as a cushion pad having a laminated structure. Even if the thickness of the first foam layer is reduced, it is possible to secure a sufficient embedding allowance for preventing a locking member such as a slit wire from coming off, and to set a slit of a deep groove. Another object of the present invention is to provide a cushion pad for a seat, and to provide a production method which can easily obtain the cushion pad by foaming in the same manner as before.

[Disclosure of the Invention]

The present invention has a laminated structure in which two types of resin foam layers having different hardnesses are laminated, and a slit for attaching a skin material is formed in a first foam layer as a surface layer, and the slit is formed. A pad in which a rod-shaped locking member is buried in the vicinity of the bottom of the groove, wherein the first foamed layer has a rear surface side at the slit forming portion joined to the rear surface thereof It is formed so as to have a bulging shape toward the second foam layer side, and the bulging portion embeds the locking member with an embedding allowance greater than or equal to a predetermined value. is there.

According to the sheet cushion pad, the back surface of the slit forming portion in the first foam layer, which is the surface layer, has a bulging shape. It is possible to set the lip depth deeper, and secure the necessary margin for preventing the locking member from being pulled out without increasing the overall thickness of the first foam layer. Can be.

Therefore, by having the swelling portion of the first foam layer, the thickness distribution of the first foam layer and the second foam layer and the depth of the slit can be arbitrarily set, respectively. The degree of freedom in setting can be increased.

The locking member has an embedding allowance of at least 10 mm between the joint surface with the second foam layer and an embedding allowance of at least 5 mm between the groove and the groove bottom of the slit. It is preferable that the locking member is buried while retaining the respective margins, so that even when the slit depth is set to a large depth as described above, it is possible to reliably remove the locking member. Can be prevented.

The present invention provides, as a method of manufacturing the cushion pad for a sheet, a lower mold for molding a pad surface, and a first upper mold and a back layer for a surface layer which can be opened and closed with respect to the lower mold. Using a mold having a second upper mold, a first foam layer as a surface layer and a second foam layer as a back layer joined to the back surface are sequentially foam-formed and laminated, and A method for manufacturing a cushion pad, wherein a slit for attaching a skin material is formed in the first foamed layer, and a bar-shaped locking member is embedded near a groove bottom of the slit. The portion corresponding to the back side of the slit forming portion of the first upper mold is moved upward to bypass the slit forming piece and the locking member arranged in the lower mold in the mold closed state. Before the injection of the first foamed resin stock solution into the lower mold. When the first upper mold is closed and the first foam layer is subjected to foam molding, the back surface of the slit forming portion of the first foam layer is bulged upward by the first upper mold. It is characterized by being molded so as to have

This allows the first foamed layer to have a bulge on the back surface side of the slit forming portion in the same molding step as in the related art. Then, by forming and laminating the second foamed layer on the first foamed layer in the same manner as in the related art, a cushion pad having a laminated structure having the above-described characteristics can be easily obtained. Can be.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of a cushion pad according to the present invention.

FIG. 2 is an enlarged sectional view of a part of the cushion pad according to the first embodiment. FIG. 3 is a schematic sectional view of a molding die for producing the cushion pad.

FIG. 4 is an enlarged cross-sectional view of a part of a cross section in a direction perpendicular to FIG. 3 showing a state in which the first foam layer is foam-formed by the same molding die.

FIG. 5 is an enlarged cross-sectional view of a part showing a state in which the second foam layer is foam-formed by the same molding die.

FIG. 6 is a sectional view showing a second embodiment of the cushion pad according to the present invention.

FIG. 7 is an enlarged sectional view of a part of the cushion pad.

FIG. 8 is a cross-sectional view of a part of a lower mold, a first upper mold, and a second upper mold for manufacturing the cushion pad of the above.

FIG. 9 is a partial cross-sectional view showing a state in which the first foam layer is foam-formed by the above-mentioned mold.

FIG. 10 is a partial cross-sectional view showing a state in which a second foam layer is foam-formed by the same molding die.

FIG. 11 is a cross-sectional view illustrating a conventional cushion pad.

FIG. 12 is an enlarged sectional view of a part of the above.

FIG. 13 is a cross-sectional view showing another example of a conventional cushion pad. FIG. 14 is an explanatory cross-sectional view of a part of the above-described cushion pad when it is molded by a conventional molding die for producing the cushion pad.

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited thereto.

FIG. 1 is a sectional view showing a first embodiment of a cushion pad according to the present invention, and FIG. 2 is an enlarged sectional view of a part of the cushion pad. The cushion pad A1 for a seat according to the present invention is made of a resin foam layer of two kinds of urethane foams having different hardness, and as shown in the figure, as a surface layer on the side facing the user, A first foam layer 1 and a second foam layer 2 as a back layer (lower layer) which is higher in density and slightly harder than the first foam layer 1 and is bonded to the back surface of the first foam layer 1 Are laminated. In the figure, la denotes a central portion serving as a seat on the pad surface, and lb and lb denote both side portions which are slightly higher than the central portion la.

In the first foam layer 1 as the surface layer, a slit 3 for attaching a skin material is provided at a required portion on the pad surface side, for example, between the central portion 1a and the side portions 1b and lb. Further, a bar-shaped locking member 5 called a slitper is buried in the vicinity of the groove bottom of the slit 3, and a skin material (not shown) such as cloth or leather is provided. By locking the locking means at the end, the device can be mounted while being sandwiched between the slits.

The first foamed layer 1 is formed such that a joint surface 6 with the second foamed layer 2 has a bulging shape toward the second foamed layer 2 on the back surface side of the slit forming portion. ing. That is, the bonding surface 6 has a curved convex shape that is recessed toward the second foam layer 2 side from the bonding surface position 6a (indicated by a virtual line) of the conventional shape on the back side of the slit forming portion. It is molded as follows. The convex bulging portion 7 allows the slit 3 to have a depth b close to, or deeper than, the joining surface position 6a of the conventional shape. A predetermined gap is provided between the groove bottom 3a of the slit 3 and the joint surface 6, and the locking member 5 embedded in this portion is formed so as to have a predetermined allowance or more. ing.

'The height of the bulging portion 7 is such that the embedding allowance c of the locking member 5 with respect to the joint surface 6 has at least 10 mm and the embedding allowance a with respect to the groove bottom 3 a has at least 5 mm. It is better to set The locking member 5 can be more reliably prevented from coming off.

The shape of the bulging portion 7 of the bonding surface 6 of the first foamed layer 1 preferably has a curve as shown in the figure, but has a bulged shape with a square cross section such as a substantially trapezoidal cross section. It may be hot.

In any case, the second foamed layer 2 laminated on the back surface of the first foamed layer 1 has a concave shape corresponding to the shape of the bulging portion 7 and the back surface of the first foamed layer 1 And are laminated and integrated.

The method for producing the cushion pad A 1 will be described below together with the apparatus used for producing the cushion pad A 1.

FIG. 3 schematically shows a molding die for molding the cushion pad A1 having the above-mentioned laminated structure, and FIGS. 4 and 5 respectively show a first foamed layer and a second foamed layer formed by the same molding die. This shows a foam molding state.

The molding die is formed in a state where the front and back of the cushion pad A 1 are inverted, and a lower die 10 having a concave shape, and two upper dies that can be opened and closed with respect to the lower die, that is, for the surface layer And a second upper mold 1 2 for the back layer. Each mold is made of a metal material such as aluminum.

The lower mold 10 is for molding a pad surface, and a slit forming piece 13 for forming a skin mounting slit 3 is formed in the mold so as to protrude. A fixed support (not shown) for detachably fixing and supporting the locking member 5 embedded in the foam is provided. For example, as shown in Fig. 1, when the slit 3 and the locking member 5 are provided between the central portion 1a serving as the seat and the side portions 1b, 1b, the position in the mold corresponding to the position is provided. The slit forming piece and the fixed support portion are disposed at the second position.

The first upper mold 11 and the second upper mold 12 are each hinged to the lower mold 10 so that the mold can be closed and opened alternately. The first upper mold 11 forms the first foam layer 1 as a surface layer with the mold closed, and the second upper mold 12 forms the second foam layer 2 with the mold closed. Thus, the two foam layers 1 and 2 can be laminated and integrated by sequentially foaming and molding. 14a and 14b in the figure each indicate a hinge joint. The mechanism for opening and closing the upper and lower dies 11 and 12 can be the same as that used in the related art.

In the first upper mold 11 of the molding die used in the present invention, a portion corresponding to the back surface side of the slit forming portion is closed with the lower mold 10 with respect to the lower mold 10. It has a shape that bulges upward in a curved convex shape so as to bypass the slit forming pieces 13 and the locking members 5 that are arranged in 10. Reference numeral 17 denotes a bulging portion of the first upper mold 11 and corresponds to the shape of the bulging portion 7 of the first foam layer 1 described above.

When the cushion pad is formed by the above-mentioned mold, the cushion pad is formed in the same procedure as in the past. First, the heat-adjusted mold is opened, and in a state in which the locking member 5 such as a wire is fixedly supported, the foamed resin stock solution blended on the lower mold 10 so as to be suitable for the first foamed layer. Inject the required amount of urethane stock solution, especially with injection head 20. Then, the first upper mold 11 is closed, foam molding is performed as shown in FIG. 4, and the first foaming is performed with the slit forming piece 13 and the locking member 5 embedded in the foam. Form layer 1. In addition, since the portion of the first upper mold 11 corresponding to the back surface of the slit forming portion has a shape bulging upward, the slit shape of the first foam layer 1 is formed. A swelling portion 7 is formed on the back surface side of the formed portion, and the locking member 5 is embedded in the swelling portion 7. The height and shape of the bulging portion 7 are determined by the bulging portion 17 of the first upper mold 11. Therefore, by appropriately setting the height of the bulging portion 17, the bulging portion 7 having an arbitrary height and shape can be formed. Thereafter, the first upper mold 11 is opened, and a required amount of a foamed resin stock solution, for example, a urea stock solution, which is blended on the first foamed layer 1 so as to be compatible with the second foamed layer, is provided. The second upper mold 12 is closed, the second foamed layer 2 is foamed as shown in FIG. 5, and the first foamed layer 1 is joined and integrated. That is, the second foamed layer 2 is foamed and formed into a shape corresponding to the bulged portion 7 on the back side of the first foamed layer 1 and laminated.

In this way, the second upper mold 12 can be opened and the molded product can be taken out, and as a result, the first foamed layer 1 having a different surface hardness and the lower layer joined to the back surface can be obtained. The cushion pad A1 having the laminated structure shown in FIG. 1 and including the second foamed layer 2 can be obtained by the same molding process as in the past.

This cushion pad A1 has a bulging portion 7 formed on the back surface side of the slit forming portion of the first foam layer 1 which is the surface layer, that is, on the joint surface side with the second foam layer 2. However, without increasing the overall thickness of the first foamed layer 1, it is possible to use the thickness of the bulging portion 7 to set the depth b of the slit 3 deep, Moreover, the engaging members 5 arranged near the groove bottom can secure necessary and sufficient embedding allowances a and c with respect to the groove bottom 3 a and the joint surface 6 of the slit 3.

Therefore, by having the swelling portion 7 of the first foam layer 1, the thickness distribution of the first foam layer 1 and the second foam layer 2 and the depth b of the slit 3 are Each can be set arbitrarily, and the degree of freedom of the setting can be increased. Further, the slit 3 of the deep groove can be provided while setting the overall thickness of the first foamed layer 1 to be thin.

Next, a second embodiment of the cushion pad of the present invention and a manufacturing apparatus thereof will be described with reference to FIGS.

In the second embodiment, in the seat cushion pad A2 having the same laminated structure as described above, the swelling portion 7 on the back surface side of the first foamed layer 1 is formed. In addition to the above configuration, a case is shown in which measures are taken to solve problems such as a feeling of convexity and a feeling of hardness of the partitioning line portion on the outer periphery of the pad.

In other words, in the case of a cushion pad having a laminated structure, for example, as shown in FIG. 13, the outer periphery of the pad has a boundary line 4 between a first foam layer 41 as a surface layer and a second foam layer 42 as a back layer. 6 appears, and a parting line PL ′ is generated by the joint between the lower mold of the molding die and the first upper mold and the second upper mold. In particular, in the case of a conventional cushion pad, as shown by a chain line in FIG. 14, the inner end of the junction between the lower mold 60 and the first upper mold 61 and the lower mold 60 and the second upper mold 61 are formed. The inner end of the joint with the mold 62 is located at the same position, and a partition line formed by the lower mold 60 and the first upper mold 61 on the outer peripheral surface of the pad, and the lower mold 60 and the second The parting line with the upper mold 62 is located at the same position, and is located on the boundary line 46. Therefore, in the part of the parting line PL ′, after molding the first foamed layer 41, when molding the second foamed layer 42, the foamed resin compounded for the second foamed layer 41 By impregnating the undiluted solution into the first foamed layer 41, the portion of the first foamed layer 41 along the boundary line 46 becomes harder than the original hardness, which is a molded product of the cushion pad. The outer periphery of the pad appears as a convex feeling and a feeling of hardness, and even in a use state in which the pad is covered with a skin material, there is a possibility that the above-mentioned convex feeling may be generated or a foreign substance may be felt by touch, thereby deteriorating the texture. is there. The structure employed in the second embodiment solves the above-described problems such as a feeling of convexity and a feeling of hardness of the partitioning line portion.

In the second embodiment, the point that the swelling portion 7 is provided on the back surface side of the slit forming portion of the first foamed layer 1 and its related configuration, and a manufacturing method for obtaining the configuration, etc. Are the same as those in the first embodiment described above, and thus the same reference numerals are given to the same components, and detailed description thereof will be omitted. A characteristic configuration of the cushion pad A2 of the second embodiment will be described. On the outer periphery of the cushion pad A2, a parting line is formed by a molding die. As shown in FIGS. 6 and 7, the parting line portion PL on the outer periphery of the pad of the second embodiment is Along the line, for example, the side of the first foam layer 1 is cut out to form a groove-shaped concave portion 8, and the first foam layer 1 and the second foam layer 2 laminated thereon are formed. A boundary line 9 appearing on the outer periphery of the pad is located in the recess 8, particularly, in the inner part. In addition, the parting line L1 at the time of molding the first foamed layer 1 is formed at the same position as the boundary line 9 as described later, and the parting line L2 at the time of molding the second foamed layer 2 is It is formed on the opening end side of the recess 8.

The molding die as a manufacturing device for obtaining the cushion pad A2 has basically the same configuration as the molding die shown in FIG. 3, and a lower die 10 for molding the pad surface side, It comprises a first upper mold 11 for the surface layer which can be opened and closed with respect to the lower mold, and a second upper mold 12 for the back layer. ,

As shown in FIGS. 8 to 10, the lower mold 10 has a joint 16 with the first upper mold 11 and the second upper mold 12 on the peripheral side thereof. On the periphery, a convex portion 15 protruding inward and extending in a circumferential direction in a rib shape is provided. The convex portion 15 may be a convex shape having a substantially trapezoidal cross-section or a substantially triangular cross-section, in addition to a convex shape having a semicircular cross-section at the tip.

The height and width of the projections 15 are preferably about 3 to 8 mm. That is, if the protrusion height or width of the convex portion 15 is smaller than the above dimension, the effect of preventing the feeling of convexity / hardness due to the formation of the concave portion 8 by the convex portion 15 cannot be sufficiently obtained, The effect of preventing lifting is also reduced. If the width of the projections 15 is too small, the strength of the projections themselves is obtained. There may be no. If the height and width of the protrusion 15 are larger than those described above, the concave portion 8 formed by the protrusion 15 will give rise to an unevenness in appearance, which is not preferable. Therefore, from the viewpoint of the above-mentioned effects, it is most preferable that the protrusion height and width of the protrusion are around 5 mm.

In addition, the projections 15 are formed at least on both sides and the front of the pad, for example, by forming the projections 15 over the entire length of the joints 16. This is preferred from the viewpoint of improving the texture of the product. Of course, it is also possible to carry out the method by providing only the both sides or the front and rear parts. On the other hand, in the state where the first upper mold 11 is closed with respect to the lower mold 10, as shown in FIG. An inner end 18 of the joint between the lower mold 10 and the first upper mold 11 is provided so as to be in contact with the upper surface of the convex part 15 so as to be located at the tip of the convex part 15. .

Further, in the state where the second upper mold 12 is closed with respect to the lower mold 10, as shown in FIG. 10, the joint portion of the outer periphery with the lower mold 10 is convex. The inner end 19 of the joint between the lower mold 10 and the second upper mold 12 is provided at the base of the projection 15 without contacting the upper surface of the part 15.

In addition, a slit forming piece 13 for forming a slit 3 for mounting a skin material is protruded at a required position in the mold of the lower mold 10, and a slit wire or the like is locked. Means necessary for shaping this kind of cushion pad, such as a support portion (not shown) of the member 5, are provided. Further, the first upper die 11 has a bulging portion 17 for forming a bulging portion 7 on the back surface side of the slit forming portion.

According to the manufacturing apparatus provided with the above-described molding die, the first foam layer 1 which becomes the surface layer by the lower mold 10 and the first upper mold 11 is formed in the same manner as in the case of the conventional apparatus. The second foam layer 2 serving as a back layer by the mold 10 and the second upper mold 12 is foam-molded sequentially and laminated and integrated, thereby providing the above-mentioned features. Produces cushion pad A2. The operation will be described.

First, open the mold that has been heated and adjusted, and put the foamed resin stock solution, especially the urethane stock solution, which is blended with the first foamed layer 1 on the lower mold 10 into the injection head 20. Inject more required amount. Then, the first upper mold 11 is closed as shown in FIG. In the closed state of the mold, the inner end side of the joint of the first upper mold 11 abuts on the convex portion 15, and the inside of the joint between the lower mold 10 and the first upper mold 11. The end 18 is located at the tip of the projection 15. Therefore, when the first foamed layer 1 is molded in this state, a concave portion 8 is formed by the convex portion 15 at the upper end of the outer peripheral portion of the first foamed layer 1 as shown in FIG. A parting line formed by 8 is formed inside the recess 8. A bulging portion 7 is formed by a bulging portion 17 on the back surface side of the slit forming portion of the first foamed layer 1 as in the case of the first embodiment.

After this molding, the first upper mold 11 is opened while the molded first foam layer 1 is left as it is, and at this time, the outer peripheral portion of the first foam layer 1 becomes the convex portion 15. Due to the engagement, the first foam layer 1 can be prevented from floating following the first upper mold 11, and the first foam layer 1 can be stably placed in the lower mold 10. Can be kept well.

Then, in the mold open state, a resin stock solution such as a urethane stock solution blended so as to be compatible with the second foam layer is injected onto the first foam layer 1, and The mold 12 is closed and the second foam layer 2 is formed as shown in FIG. At this time, the second upper mold 12 does not come into contact with the upper surface of the convex portion 15 and the inner end 19 of the joint between the lower mold 10 and the second upper mold 12 has the convex shape. Department It is located at the base of the upper surface of 15. Therefore, the second foam layer 2 formed and laminated on the first foam layer 1 is formed so as to cover the upper surface of the convex portion 15 as shown in the figure, and the second foam layer 2 is formed on the outer periphery of the pad. The groove 15 is formed by the part 15, and the parting line by the inner end 19 of the joint is formed at the opening end of the recess 8.

Thereby, the first foamed layer 1 and the second foamed layer 2 are laminated and integrated, and the cushion pad A2 having the form shown in FIG. 6 is obtained. In the partitioning line portion PL on the outer periphery of the cushion pad A2, as shown in an enlarged view in FIG. 7, the lower mold 10 and the first upper mold 11 when the first foamed layer 1 is formed. Parting line L 1 at the joint end 19 between the lower mold 10 and the second upper mold 12 at the time of forming the second foamed layer 2, and the partitioning line L 1 at the joint inner end 18 of Are formed in the inner deep portion and the opening end of the concave portion 8. Further, a boundary line 9 between the first foamed layer 1 and the second foamed layer 2 which coincides with the parting line L1 formed by the inner end 18 of the joint portion is located in the inner part of the recess 8 and It does not appear on the outer peripheral surface.

For this reason, the cushion pad A 2 can be used as a conventional packing line on the outer peripheral surface of the pad even if the resin stock solution of the second foam layer 2 may impregnate the first foam layer 1. Such a convex feeling and a feeling of hardness do not occur, and the texture in the use state in which the skin material is covered on the cushion pad A 2 can be secured well.

In particular, if the projections 15 are provided at least on both sides and the front part of the pad, the cushion pad A 2 obtained by this means that the parting line of the portion that is easily conspicuous in appearance when used is used. In the part PL, the convexity ゃ does not cause a foreign object sensation to the touch.

In the above-described embodiment, the case where the concave portion 8 formed by the convex portion 15 is formed on the side of the first foam layer 1 has been described. Alternatively, a concave portion extending over both the first foamed layer 1 and the second foamed layer 2 may be formed.

Further, in order to eliminate the structure of the partitioning line portion PL of the second embodiment, that is, the feeling of convexity and hardness of the partitioning line, a groove-like concave portion 8 is formed along the line. The parting line L 1 at the time of molding the first foam layer 1 and the parting line L 2 at the time of molding the second foam layer 2 This point can also be applied to a cushioning pad or pad having no bulging portion on the back surface side of the slit forming portion of the first foaming layer 1.

The features of the cushion pad of the second embodiment and the manufacturing apparatus thereof can be summarized as follows.

(a) A cushion pad for a sheet having a laminated structure having two types of resin foam layers having different hardnesses as front and back layers, and a parting line portion on an outer periphery of the node is at least along the line. A groove-shaped recess is formed on the side of the first foam layer as a surface layer, and a boundary between the first foam layer and a second foam layer laminated thereon is located in the recess. What you have.

(b) An apparatus for manufacturing a cushion pad for a sheet having a laminated structure having two types of resin foam layers having different hardnesses as front and back layers, and a lower mold for molding the pad surface, and an opening and closing for the lower mold, respectively. It comprises a mold having a first upper mold for a free surface layer and a second upper mold for a back layer, and comprises a first foam layer as a surface layer and a second foam layer as a back layer. In the manufacturing apparatus, which is formed by foaming and laminating sequentially, the lower mold has a protrusion protruding inward at an inner peripheral edge of a joint portion with the first upper mold and the second upper mold. An inner end of a joint between the lower mold and the first upper mold is at a tip end side of the convex portion, and an inner end of a joint between the lower mold and the second upper mold is an upper surface of the convex portion. It is provided so as to be located on the base side. (C) The seat cushion pad manufacturing apparatus, wherein the projections are provided at least on both side portions and a front portion of the pad.

(d) In the seat cushion pad manufacturing apparatus, the height and width of the projection are about 3 to 8 mm, respectively.

[Possibility of industrial use]

The present invention provides a cushion pad having a laminated structure in which two types of resin foam layers having different hardnesses are laminated, and has a high degree of freedom in setting the thickness distribution of the foam layer and the depth of the slit for mounting the skin material, and has a deep groove slot. Since it is possible to provide a slidable member which can secure a sufficient margin for embedding a locking member such as a slit wire, it can be suitably used for a cushion pad for a seat of an automobile or the like.

Claims

Scope of the request A laminated structure in which two types of resin foam layers having different hardness are laminated is formed, and a slit for attaching a skin material is formed in the first foam layer as a surface layer, and the slit is formed. A cushion pad in which a rod-shaped locking member is embedded near the bottom of the groove

The first foamed layer is formed so that the back surface side of the slit forming portion has a bulged shape toward the second foamed layer side joined to the back surface, and the bulged portion is used for the engagement. A cushion pad for a seat, wherein the stopper member is embedded with a predetermined allowance for embedding.

An embedding margin of at least 10 mm between the locking member and the joint surface with the second foam layer, and an embedding margin of at least 5 mm between the locking member and the groove bottom of the slit. 2. The seat cushion node according to claim 1, wherein the seat cushion node is buried in a state where each of them is buried.

A lower mold for molding the pad surface, and a mold having a first upper mold for the surface layer and a second upper mold for the lower layer, each of which can be opened and closed with respect to the lower mold, are used. A first foam layer as a base material and a second foam layer as a lower layer to be bonded to the back surface are sequentially foamed and laminated, and the first foam layer is provided with a slit for mounting a skin material. Forming a rod-shaped locking member near the groove bottom of the slit.

A portion corresponding to a back surface side of the slit forming portion of the first upper mold is bulged upward to bypass a slit forming piece and a locking member arranged in the lower mold in a mold closed state. A first foamed resin stock solution is poured into the lower mold, the first upper mold is closed, and the first mold is closed. When the foam layer is foam-molded, the first upper mold is formed so that the back side of the slit forming portion of the first foam layer has a bulge upward. Manufacturing method of cushion pad for seat.