JP2011045548A - Foamed molding for seat pad and method for manufacturing seat pad - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a foamed molding for a seat pad, which is unlikely to cause variations in outer surface shape of the seat pad after removing burrs, and to provide a method for manufacturing a seat pad. <P>SOLUTION: A vent hole T is formed of recessed part 5 and 6 provided on the front surface 3 and rear surface 4 of the foamed molding 1 respectively. A part between the bottom surfaces of the recessed parts 5 and 6 is the burr part 2. The burr part 2 is formed at a position retreated into the vent hole T from the front surface 3 and the rear surface 4. A relatively thin part 2a is formed along the peripheral edge part of the burr part 2, and the center side of the burr part 2 is formed as a relatively thick part 2b. The thin part 2a is formed over the entire periphery of the burr part 2. When manufacturing the seat back from the foamed molding 1, an operator inserts a finger to the recessed part 5 or the recessed part 6 and pushes the thick part 2b of the burr part 2. Thus, stress is concentrated on the thin part 2a of the burr part 2 to break the thin part 2a and the burr part 2 is separated from the foamed molding 1. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a seat pad foam molded body for constituting a seat pad having a seat pad main body and a hole penetrating the seat pad main body, and in particular, a burr portion that blocks the hole integrally with the seat pad main body. The present invention relates to a foam molded body for a seat pad in which the hole penetrates the seat pad main body by removing the burr portion. The present invention also relates to a seat pad manufacturing method for manufacturing a seat pad from the foamed molded product for seat pad.

  A vehicle seat or a seat such as a sofa installed in a house includes a seat pad made of a foamed synthetic resin such as a soft polyurethane foam or a semi-rigid polyurethane foam, and a skin material mounted on the surface of the seat pad.

  It has been widely practiced to provide a hole through the seat pad from the seating person facing surface of the seat pad to the side surface opposite to the seat pad. When air flows through the hole, air permeability between the seated person and the seat is ensured.

  In order to form a seat pad having such a through hole, a convex part having a through hole shape is provided on the upper die, lower die or core of the mold for forming the seat pad. FIG. 6 (a) is a schematic longitudinal sectional view of a conventional general mold for forming a seat pad with a through hole, and FIG. 6 (b) shows a seat pad formed by this mold. It is a longitudinal cross-sectional view. As shown in FIG. 6 (a), the mold 110 has an upper mold 111 and a lower mold 112 (further, if necessary), and supplies a foaming raw material such as urethane into the lower mold 112, The seat pad 100 is formed by mold-clamping and foaming. The seat pad 100 is generally molded in the mold 110 in a posture in which the seated person facing surface is directed downward. In this conventional example, a support material (101) is integrally formed on a surface (hereinafter, also referred to as a back surface) opposite to the seated person facing surface of the seat pad 100.

  In this conventional example, a convex portion 113 for forming a hole protrudes from the bottom surface of the cavity of the lower mold 112. Due to the convex portion 113, a hole 102 is formed in the seat pad 100 from the seating person facing surface toward the back surface side. That is, the portion where the convex portion 113 was present at the time of foam molding becomes the hole 102.

  In a state where the upper mold 111 and the lower mold 112 are clamped, the front end surface (upper end surface) of the convex portion 113 is slightly separated from the ceiling surface of the cavity of the upper mold 111. This is for ensuring adhesion of the joint surface between the upper mold 111 and the lower mold 112 and preventing air from being collected around the hole 102 during foam molding. That is, since the tip surface of the convex portion 113 is separated from the ceiling surface of the cavity of the upper mold 111 in this way, a corner where the outer peripheral surface of the convex portion 113 and the ceiling surface of the cavity of the upper mold 111 intersect at the time of foam molding. Even if air remains in the part, the air enters the gap between the convex part 113 and the upper mold 111 together with the foamed resin. Accordingly, in the seat pad 100 foam-molded by the mold 110, the foamed resin enters the gap between the projection 113 and the upper mold 111 during foam molding, as shown in FIG. 6 (b). A thin skin-like burr 103 that closes the hole 102 is generated. Therefore, it is necessary to remove this burr part 103 after demolding.

  Japanese Utility Model Laid-Open No. 55-166622 describes a seat pad molding die configured to facilitate the removal of the burr 103. FIG. 7 (a) is a longitudinal sectional view of a die of the same number, and FIG. 7 (b) is a longitudinal sectional view of a seat pad formed by this die. In this mold 110 ′, as shown in FIG. 7 (a), a recess recessed toward the outside of the mold in a region facing the tip surface of the convex portion 113 on the cavity ceiling surface of the upper mold 111. 114 is provided. At the time of foam molding, the foamed resin enters the recess 114 through a gap between the tip surface of the convex portion 113 and the cavity ceiling surface of the upper mold 111. Accordingly, the burr lump protruding from the outer surface of the seat pad 100 ′ is formed on the seat pad 100 ′ formed by the mold 110 ′ by the foamed resin that has entered the recess 114 as shown in FIG. 104 is formed. For this reason, when removing the burr portion 103 blocking the hole 102 after demolding, the burr lump 104 can be easily picked and removed.

Shokai 55-166622

  In the above-mentioned Japanese Utility Model Laid-Open No. 55-166622, when the burr part 103 is removed, when an operator picks the burr lump 104 with a finger and peels off the burr part 103, a part of the burr part 103 is formed on the peripheral edge of the hole 102. It may remain or the peripheral edge of the hole 102 may be missing. In the same number, since the burr part 103 is formed along the outer surface of the seat pad 100 ′, if the burr part 103 remains in the peripheral part of the hole 102 or the peripheral part of the hole 102 is missing, The outer surface shape of the seat pad 100 ′ around the hole 102 varies.

  In the present invention, a burr portion is formed integrally with the seat pad main body to close a hole penetrating the seat pad main body, and the hole penetrates the seat pad main body by removing the burr portion. In a foamed product for a seat pad, there are provided a foamed product for a seatpad in which the outer shape of the seatpad after the removal of the burr portion is less likely to vary, and a method for producing the seatpad from the foamed product for the seatpad. For the purpose.

  A foamed molded product for a seat pad according to the present invention (Claim 1) has a seat pad main body having a seating person facing surface and a hole penetrating the seat pad main body from the seating person facing surface to the opposite side surface. A foam molded body for constituting a pad, wherein a burr portion for closing the hole is formed integrally with the seat pad main body, and the hole is formed into the seat pad main body by removing the burr portion. In the foam molded body for a seat pad that penetrates the seat pad, the burr portion is formed at a position retracted in the hole from the seating person facing surface and the opposite side surface. .

  The foam molded body for a seat pad according to claim 2 is characterized in that, in claim 1, the burr part is retreated 5 to 10 mm into the hole from the seating person facing surface and the opposite side surface. is there.

  The foamed molded product for a seat pad according to claim 3 is the member according to claim 1 or 2, wherein the burr portion is broken when the burr portion is pushed from the side facing the seated person or the opposite surface side. In addition, a fragile portion configured to separate the burr portion from the seat pad main body is provided.

  The foamed molded product for a seat pad according to claim 4 is the foamed molded body according to claim 3, wherein a thin portion having a relatively small thickness is formed at the peripheral portion of the burr portion, and the center side of the burr portion is more than the thin portion. The thin portion is thicker than the thin portion, and the thin portion is the fragile portion.

  The foamed molded product for a seat pad according to claim 5 is characterized in that, in claim 4, the thin portion is formed over the entire circumference of the burr portion.

Seat pad foam molded article of claim 6, according to claim 4 or 5, the thickness _{T 1} of the thin portion is 1.0 to 1.5 mm, the thickness _{T 2} of the thick portion 2. It is 0 to 6.0 mm.

  The foamed molded product for a seat pad according to claim 7 is characterized in that, in any one of claims 4 to 6, a width W of the thin portion in a radial direction of the hole is 2.0 to 3.0 mm. To do.

  The foamed molded product for a seat pad according to claim 8 is characterized in that, in any one of claims 4 to 7, the opening shape of the hole is circular or elliptical.

  The foamed molded product for a seat pad according to claim 9 is the seat pad facing surface side surface of the burr part, which is flush with the thick part from the thin part in any one of claims 4 to 8. It is characterized by having a substantially flat surface.

  A seat pad manufacturing method according to the present invention (invention 10) is a method for manufacturing a seat pad by removing the burr part from the foamed molded product for a seat pad according to any one of claims 1 to 9. It is.

  The seat pad manufacturing method according to an eleventh aspect is characterized in that, in the tenth aspect, the burrs are removed by pushing the burrs through the holes.

  In the foam molded body for seat pad according to the present invention, the burr portion is formed at a position retracted into the hole from the seating person facing surface of the seat pad main body and the opposite surface, so the burr portion is temporarily removed. In this case, even if the peripheral portion of the burr portion remains slightly on the inner peripheral surface of the hole or the inner peripheral surface of the hole is slightly chipped, There is virtually no effect on the shape. Thereby, it is prevented that the outer surface shape of the seat pad main body after the removal of the burr portion is uneven.

  The foam material becomes harder in the burr portion of the foam molded body and the portion connected to the burr portion than in other portions. Therefore, as described in claim 2, it is preferable that the burr part is retreated 5 to 10 mm into the hole from the seating person facing surface of the seat pad main body and the surface opposite thereto. When the retraction amount of the burr part is smaller than 5 mm, the seated person can easily sense the hardened foam material around the burr part. Moreover, when the retraction amount of this burr | flash part is larger than 10 mm, when inserting a finger etc. in a hole and pushing a burr | flash part, it will become difficult to push a burr | flash part.

  In the aspect of Claim 3, the weak part is provided in the peripheral part of the burr | flash part, and the center part of this burr | flash part is seated from the seating person opposite surface side of a seat pad main body, or the other side through this hole. By pressing, the fragile part is broken and the burr part is separated from the seat pad body, so that the burr part can be easily removed.

  In the aspect of Claim 4, since the thin part is formed in the peripheral part of the burr part, when pushing the thick part in the center of the burr part, stress concentrates on this thin part, The thin portion is easily broken.

  In the aspect of the fifth aspect, since the thin portion is formed over the entire circumference of the burr portion, it is possible to easily remove substantially the whole burr portion by breaking the burr portion along the thin portion. .

As in Claim 6, the thickness _{T 1} of the thin portion is 1.0 to 1.5 mm, the thickness _{T 2} of the thick portion is preferably 2.0 to 6.0 mm. With this configuration, when the thick portion is pushed, the thin portion is broken without breaking the thick portion.

  As described in claim 7, the width W of the thin portion in the radial direction of the hole is preferably 2.0 to 3.0 mm. If the width W of the thin portion is in the range of 2.0 to 3.0 mm, the thin portion can be easily broken without remaining in the seat pad body. If the width W of the thin wall portion is larger than 3.0 mm, the thin wall portion is broken in the middle in the width direction when the thick wall portion is pushed, and the thin wall portion is partially left in the seat pad body. There is a risk that.

  If the opening shape of the hole is a polygonal shape such as a polygon, when the burr portion is removed, a thin-walled portion tends to remain in the corner portion. The shape is preferably circular or elliptical.

  As described above, in general, the seat pad is molded in a posture in which the seated person facing surface faces downward in the mold. Therefore, it is preferable that the surface of the burr portion on the side facing the seated person is a substantially flat surface that is flush from the thin portion to the thick portion. With this configuration, when the mold is opened and the foamed molded product is taken out from the lower mold, the burr part easily separates from the cavity inner surface of the lower mold, so that the burr part remains in the lower mold. The foamed molded product can be taken out from the lower mold without any problem.

  The seat pad manufacturing method of the present invention is a method of manufacturing a seat pad by removing the burrs from the foam molded body for seat pad of the present invention. At this time, as in the eleventh aspect, the burrs can be easily separated from the seat pad body by pushing the burrs through the holes.

It is a front view of the foaming molding for seat pads concerning an embodiment. It is an enlarged view of the II part of FIG. It is sectional drawing which follows the III-III line of FIG. It is sectional drawing of the part similar to FIG. 3 which shows the removal operation | work of the burr | flash part in a vent hole. It is a schematic longitudinal cross-sectional view of the metal mold | die for shape | molding the foaming molding for seat pads of FIG. It is a longitudinal cross-sectional view of the foaming molding for seat pads which concerns on a prior art example, and its shaping | molding metal mold | die. It is a longitudinal cross-sectional view of the foaming molding for seat pads which concerns on a prior art example, and its shaping | molding metal mold | die.

  Hereinafter, embodiments will be described with reference to the drawings. In the following embodiments, a foamed molded body for a seat pad for constituting a seat back (backrest portion) of a vehicle seat is illustrated, but the present invention is a seat constituting another part of the seat. The present invention can also be applied to a foamed molded product for pads, and can also be applied to a foamed molded product for seatpads for constituting a seatpad for a sheet other than a vehicle seat.

  FIG. 1 is a front view of a foamed product for seat pad according to an embodiment. FIG. 2 is an enlarged view of an enlarged view (portion II in FIG. 1) of a vent hole portion of this foam molded article. FIG. 3 is a sectional view taken along line III-III in FIG. FIG. 4 is a cross-sectional view of the same part as in FIG. 3, showing the operation of removing the burr in the vent hole. FIG. 5 (a) is a schematic longitudinal sectional view of a mold for molding the foam molded article, and FIG. 5 (b) is an enlarged view of the vicinity of the vent hole forming convex portion of the mold. It is.

  A foamed molded product for seat pad (hereinafter sometimes simply referred to as a foamed molded product) 1 of this embodiment is for constituting a seat back of a vehicle seat. The foam molded body 1 is molded from a foamed synthetic resin such as a flexible polyurethane foam or a semi-rigid polyurethane foam. Hereinafter, the front and rear, the left and right, and the vertical direction of the foam molded body 1 substantially coincide with the front and rear, the left and right, and the vertical direction for the seated person of the vehicle seat. The seat back includes a seat back main body formed by the foam molded body 1 and a vent hole T penetrating through the seat back main body in a substantially front-rear direction (a thickness direction of the seat back main body). As shown in FIGS. 2 and 3, at the molding stage of the foam molded body 1, the burr portion 2 is formed integrally with the seat back body so as to close the vent hole T. By removing the burr part 2, the vent hole T penetrates the seat back body. In this embodiment, as shown in FIG. 1, the foam molded body 1 is configured such that a total of six vent holes T are formed in the vicinity of the center of the front surface, with the arrangement positions being different vertically and horizontally. However, the number and arrangement of the vent holes T are not limited to this.

  As shown in FIG. 3, each air hole T includes a first recess 5 that is recessed from the front surface 3 to the rear surface 4 side and a second recess 6 that is recessed from the rear surface 4 toward the front surface 3. It is formed. The burr part 2 is formed between the bottom surfaces of the recesses 5 and 6. In this embodiment, the recesses 5 and 6 each have a substantially circular shape in a plan view (or a cross-sectional shape in a direction perpendicular to the axial direction) and are disposed substantially coaxially with each other. . The concave portion 5 has a tapered shape whose diameter increases toward the front surface 3 side, and the concave portion 6 has a tapered shape whose diameter increases toward the rear surface 4 side. The bottoms of the recesses 5 and 6 have substantially the same diameter. Moreover, the diameter in the same plane as the front surface 3 of this recessed part 5 and the diameter in the same plane as the rear surface 4 of the recessed part 6 are also substantially the same diameter. In this embodiment, the outer surface of the corner portion where the inner peripheral surface of the concave portion 5 and the front surface 3 intersect, and the outer surface of the corner portion where the inner peripheral surface of the concave portion 6 and the rear surface 4 intersect, respectively, have a predetermined radius of curvature R. In FIG. 3, it is curved in a substantially arc shape. However, the shape of the recesses 5 and 6 is not limited to this.

  In the present invention, it is preferable that the planar view shape of the recesses 5 and 6 is a substantially circular shape or a substantially elliptical shape. When the shape of the vent hole T in plan view is a polygonal shape such as a polygon, when the burr portion 2 is removed, a thin portion 2a described later tends to remain in the corner portion.

  As shown in FIG. 3, in this embodiment, the depth of the recess 6 is larger than the depth of the recess 5. The depth of the recess 5, that is, the retraction amount D of the burr part 2 from the front surface 3 of the foamed molded body 1 is preferably 5 to 10 mm. In this embodiment, the depth of the recess 5 is substantially equal to the radius of curvature R of the corner outer surface where the inner peripheral surface of the recess 5 and the front surface 3 intersect. In contrast, the depth of the recess 5 may be larger than the depth of the recess 6. In this case, it is preferable that the depth of the recessed portion 6, that is, the retraction amount of the burr portion 2 from the rear surface 4 of the foamed molded body 1 is 5 to 10 mm. Alternatively, the depth of the recess 5 and the depth of the recess 6 may be substantially equal.

  In addition, the burr | flash part 2 and the part connected to this of the foaming molding 1 become harder than other parts. Therefore, if the retraction amount D of the burr part 2 from the front surface 3 or the rear surface 4 of the foam molded body 1 is smaller than 5 mm, the hardened portion is easily perceived by the seated person, and the sitting comfort is lowered. Further, when the retraction amount D of the burr part 2 from the front surface 3 or the rear surface 4 of the foam molded body 1 is larger than 10 mm, the respective recesses 5 and 6 are formed when foam molding is performed by the mold 10 described later. The urethane raw material becomes difficult to enter between the convex portions 13, 14, and the moldability of the burr portion 2 is deteriorated.

As shown in FIGS. 2 and 3, in this embodiment, the burr portion 2 has a substantially disk shape in which the disc surface extends in a direction substantially orthogonal to the axial direction of the recesses 5 and 6, and its peripheral portion is It continues to the inner peripheral surface of the recesses 5 and 6. A thin portion 2a having a relatively small thickness is formed along the peripheral portion of the burr portion 2, and a central portion of the burr portion 2 is a thick portion 2b having a relatively large thickness. Yes. The thin portion 2 a is formed over the entire circumference of the burr portion 2. By this thin portion 2a, a fragile portion is formed that breaks when the burr portion 2 (thick portion 2b) is pushed from the front surface 3 side or the rear surface 4 side and separates the burr portion 2 from the foamed molded body 1. Yes. The thickness T ₁ of the thin portion 2a is preferably 1.0 to 1.5 mm, and the thickness T ₂ of the thick portion 2b is 2.0 to 6.0 mm, particularly 3.0 to 5.0 mm. It is preferable that The width W of the thin portion 2a in the diameter direction of the burr portion 2 (that is, the diameter direction of the recesses 5 and 6) is preferably 2.0 to 3.0 mm.

Incidentally, the thickness T ₁ of the thin portion 2a is smaller than 1.0 mm, the air bleeding effect due to the formation of the burr portion 2 is not sufficiently exhibited, or resulting reservoir air around the recesses 5 and 6, When the molded foam 1 is removed, the burr 2 may be broken and remain in the mold. If the burr 2 remains in the mold during demolding, the maintenance becomes troublesome. Moreover, when performing foam molding repeatedly, it is necessary to perform the operation | work which removes the burr | flash part 2 from the inside of a metal mold | die, and work efficiency falls. When the thickness T ₁ of the thin portion 2a is larger than 1.5mm, or less likely to break the thin portion 2a also press the thick portion 2b worker with a finger when removing burrs section 2, the thin-walled portion There is a possibility that the burr part 2 or the foamed molded body 1 may be broken at a part other than 2a. If the width W of the thin wall portion 2a is larger than 3.0 mm, the thin wall portion 2a breaks in the middle in the width direction when the thick wall portion 2b is pressed, and the thin wall portion 2a May remain. If the thickness T ₂ of the thick portion 2b is smaller than 2.0 mm, there is a possibility that the thick portion 2b is broken when the thick portion 2b worker presses with a finger. When the thickness T ₂ of the thick portion 2b is larger than 6.0 mm, hardly extracted the thick portion 2b from recess thick portion 2b formed of the mold during demolding.

  In this embodiment, as shown in FIG. 3, the thick part 2b has a front surface that is substantially flush with the front surface of the thin part 2a, and a rear surface that protrudes rearward from the thin part 2a. ing. The reason for this will be described in detail later. In addition, the shape of the burr | flash part 2 is not limited to this.

  Next, the structure of the metal mold | die 10 for shape | molding this foaming molding 1 is demonstrated.

  In this embodiment, the mold 10 includes an upper mold 11 and a lower mold 12. In the cavity of the mold 10, the foam molded body 1 is molded in a posture in which the front surface is directed downward. That is, the front surface of the foam molded body 1 is molded by the cavity inner surface (bottom surface) of the lower mold 12, and the rear surface of the foam molded body 1 is molded by the cavity inner surface (ceiling surface) of the upper mold 11. From the cavity inner surface of the lower mold 12, a first convex portion 13 for forming the concave portion 5 on the front surface of the foam molded body 1 is projected, and from the cavity inner surface of the upper mold 11, the foam molded body 1 A second convex portion 14 is formed so as to project the rear convex portion 14. In FIGS. 5 (a) and 5 (b), the convex portions 13 and 14 are shown one by one, but the same number as the vent holes T provided in the seat back is provided. In this embodiment, each of the convex portions 13 and 14 has a substantially cylindrical shape. In addition, each convex part 13 and 14 is a taper shape in which a diameter becomes small, respectively, considering the ease of extracting from the recessed parts 5 and 6 at the time of mold removal. In a state where the upper mold 11 is put on the lower mold 12 and the mold is clamped, the convex portions 13 and 14 are arranged substantially coaxially, and the respective end faces face each other. The convex portions 13 and 14 are configured such that a gap S is generated between the respective front end surfaces in this clamping state.

In this embodiment, the front end surface (upper end surface) of the first convex portion 13 is a substantially horizontal flat surface. A concave portion 14 a that is recessed upward is provided on the distal end surface of the second convex portion 14. The recess 14 a is disposed away from the peripheral edge of the tip surface of the second convex portion 14 toward the center of the tip surface. In this embodiment, the recess 14 a has a substantially circular plan view shape having a smaller diameter than the distal end surface of the second convex portion 14, and is substantially concentric with the distal end surface of the second convex portion 14. Arranged in a shape. In the mold-clamping state, the ceiling surface of the recess 14a and the outer peripheral side of the recess 14a of the tip surface of the second convex portion 14 are respectively the same as the tip surface of the first convex portion 13 and the predetermined surface. It faces almost parallel with an interval. Incidentally, the ceiling surface and the distance between the distal end surface of the first convex portion 13 is the same as the thickness T ₂ of the thick portion 2b of the burr portion 2, the distal end surface of the second convex portion 14 of the recess 14a the outer peripheral side of the recess 14a of the distance between the distal end surface of first projection 13 is the same as the thickness T ₁ of the thin portion 2a. The configuration of the mold 10 is not limited to this. For example, the mold 10 may include a core as necessary. In this case, the core T may be provided with a convex portion for forming the vent hole T.

  At the time of foam molding, the burr portion 2 is formed by the foam material such as urethane entering the gap S between the front end surfaces of the first convex portion 13 and the second convex portion 14. At this time, the air left at the corner where the cavity inner surface of the lower mold 12 and the outer peripheral surface of the first protrusion 13 intersect also enters between the tip surfaces. Thereby, it is prevented that an air pool arises around the recessed parts 5 and 6 of the foaming molding 1. A thick part 2b having a relatively large thickness is formed between the ceiling surface of the recess 14a and the front end surface of the first convex part 13, and from the recess 14a on the front end surface of the second convex part 14. Also, a thin portion 2 a having a relatively small thickness is formed between the outer peripheral side and the tip surface of the first convex portion 13.

  After foam molding, the upper mold 11 is opened, and the foam molded article 1 is taken out from the lower mold 12. As described above, in this embodiment, the tip surface of the first convex portion 13 is not provided with a recess for forming the thick portion 2b. Thus, the front surface of the burr part 2 is a substantially flat surface that continues from the thin part 2a to the thick part 2b. That is, the thick portion 2 b of the burr portion 2 is not engaged with the tip surface of the first convex portion 13. Thereby, at the time of mold removal, the burr | flash part 2 separates easily from the front end surface of the 1st convex part 13, Therefore The foaming molding 1 can be taken out from the lower mold | type 12 smoothly. If a recess for forming the thick portion 2b is also provided on the tip surface of the first convex portion 13, the thin portion 2a is removed when the thick portion 2b is extracted from the recess during demolding. Care must be taken that the thick part 2b does not remain in the recess due to breakage or the thick part 2b itself being partially broken.

  In manufacturing the seat back from the foamed molded body 1, as shown in FIG. 4, the operator inserts a finger into the concave portion 5 or the concave portion 6 and pushes the thick portion 2 b of the burr portion 2. Thereby, stress concentrates on the thin part 2a of the burr part 2, the thin part 2a is broken, and the burr part 2 is separated from the foam molded body 1. As a result, the vent hole T penetrates the seat back body (foamed molded body 1) in the thickness direction. Then, the seat back having the air holes T is completed by performing finish processing of the fractured surfaces in the recesses 5 and 6 as necessary.

  In the foamed molded body 1, the fragile part made of the thin part 2 a is provided at the peripheral part of the burr part 2, so that by pressing the thick part at the center of the burr part 2, The burr | flash part 2 can be removed by breaking the thin part 2a. Further, in this foam molded body 1, the burr part 2 is formed at a position retracted from the front surface 3 and the rear surface 4 of the foam molded body 1 into the vent hole T. Therefore, even if the thinned portion 2a remains slightly on the inner peripheral surface of the vent hole T or the inner peripheral surface of the vent hole T is slightly missing when the burr portion 2 is removed, the front surface of the foam molded body 1 is removed. 3 and the shape of the rear face 4 have virtually no effect. Thereby, it is prevented that the outer surface shape of the seat back after removing the burr part 2 is uneven.

  In this embodiment, since the thin portion 2a is formed at the peripheral portion of the burr portion 2, when the thick portion 2b at the center of the burr portion 2 is pressed, stress concentrates on the thin portion 2a, and the burr portion 2 is easily broken from the thin portion 2a. Since the thin portion 2a is formed over the entire circumference of the burr portion 2, it is possible to easily remove substantially the whole burr portion 2 by breaking the burr portion 2 along the thin portion 2a.

The thickness _{T 1} of the thin portion 2a and 1.0 to 1.5 mm, the thickness _{T 2} of the thick portion 2b by a 2.0 to 6.0 mm, when the thick portion 2b is pressed The thin-walled portion 2a is broken without breaking the thick-walled portion 2b. Therefore, workability when removing the burr part 2 from the foamed molded body 1 is good.

[Examples and Comparative Examples]
In the above embodiment, the thin portion 2a of the burr portion 2 having a thickness T ₁ and the thick portion 2b of the _second thickness T ₂ as the dimension in Table 1, and demolding of the lower die 12 of the burr 2 Workability at the time of removal from the foamed molded product 1 was evaluated. In any of Examples 1 to 3 and Comparative Examples 1 and 2, the width W of the thin portion 2a was 2 mm, and the removal of the burr portion 2 was performed by the operator pressing the thick portion 2b with a finger. ○ in the column of evaluation in Table 1 indicates that the demolding property from the lower mold 12 of the burr part 2 and the workability at the time of removal from the foamed molded body 1 were both good, and × indicates these It indicates that at least one of them was defective.

  As shown in Table 1, in Examples 1 to 3, the burr part 2 did not remain in the lower mold 12 during demolding, and could be demolded integrally with the foamed molded body 1. In removing the burr part 2, when the operator pushes the thick part 2b with his / her finger, only the thin part 2a is broken, and the entire burr part 2 is entirely inside the vent hole T only by this pressing work. Removed from. Therefore, the processing operation of the fracture surface of the foam molded body 1 after removing the burr part 2 was unnecessary. On the other hand, in Comparative Example 1, since the thin portion 2a is too thin, at the time of demolding, the thin portion 2a was broken before the burr portion 2 was peeled off from the lower die 12, and the burr portion 2 remained in the lower die 12. . Therefore, it is necessary to maintain the lower mold 12 every time foam molding is performed. In Comparative Example 2, the demoldability from the lower mold 12 was good. However, since the thin-walled portion 2a is too thick, the thin-walled portion 2a cannot be easily broken when an operator presses the thick-walled portion 2b with a finger when removing the burr portion 2. At this time, when a strong force was applied, the thick portion 2a was broken. Therefore, it was necessary to remove the burr part 2 using a cutter or the like.

As explained above, the thin portion 2a of the burr portion 2 a thickness _{T 1} and 1.0 to 1.5 mm, the thickness _{T 2} of the thick portion 2b 2.0 to 6.0 mm, especially 3.0 to 5. By setting it to 0 mm, the demolding property from the lower mold 12 of the burr part 2 and the workability at the time of removal from the foamed molded product 1 are improved.

  Each of the above configurations is an example of the present invention, and the present invention may have configurations other than those described above.

  For example, in the above-described embodiment, the front surface of the burr portion 2 is a flat surface continuous from the thin portion 2a to the thick portion 2b, but the foamed molded body 1 has the rear surface 4 facing downward in the mold 10. When the molded body is molded in such a posture (that is, the rear surface 4 of the foam molded body 1 is molded by the cavity inner surface of the lower mold 12), the rear surface of the burr portion 2 is continuous from the thin portion 2a to the thick portion 2b. It may be a flat surface. The thick part 2b may be formed so as to protrude from both front and rear surfaces of the burr part 2.

  In the above embodiment, the foam molded body 1 is for constituting a seat back of a vehicle seat. However, the present invention can be applied to other parts of the seat such as a seat cushion (seat portion), a headrest, and an armrest. The present invention can also be applied to a foam molded body for a seat pad for constituting the like. Further, the present invention is also applicable to a seat pad foam molded body for constituting a seat pad for a seat other than a vehicle seat.

DESCRIPTION OF SYMBOLS 1 Foam molding 2 Burr part 2a Thin part 2b Thick part 3 Front surface of foam molding 4 Rear surface of foam molding 5 1st recessed part 6 2nd recessed part 10 Mold 11 Upper mold 12 Lower mold 13 1st convex Part 14 Second convex part 14a Thick part forming recess

Claims (11)

A foam molded body for constituting a seat pad having a seat pad main body having a seating person facing surface and a hole penetrating the seat pad main body from the seating person facing surface to the opposite side surface thereof,
In the foam molded body for a seat pad, a burr portion for closing the hole is formed integrally with the seat pad main body, and the hole penetrates the seat pad main body by removing the burr portion. ,
The burr portion is formed at a position recessed in the hole with respect to the seating person facing surface and the opposite side surface.   2. The seat pad foam molded body according to claim 1, wherein the burr portion is recessed 5 to 10 mm into the hole from the seating person facing surface and the opposite side surface.   3. The burr portion according to claim 1, wherein the burr portion is broken when the burr portion is pushed from the seating person facing surface side or the opposite surface side to separate the burr portion from the seat pad main body. A foamed article for a seat pad, characterized in that a fragile part configured to be made is provided.   In Claim 3, the thin part with comparatively small thickness is formed in the peripheral part of the said burr | flash part, and this burr | flash part center side becomes a thick part thicker than this thin part rather than this thin part. A foamed molded product for a seat pad, wherein the thin portion is the fragile portion.   5. The foamed molded product for a seat pad according to claim 4, wherein the thin portion is formed over the entire circumference of the burr portion. According to claim 4 or 5, the thickness _{T 1} of the thin portion is 1.0 to 1.5 mm, and the thickness _{T 2} of the said thick portion is 2.0~6.0mm Foam molded body for seat pads.   The foamed molded product for a seat pad according to any one of claims 4 to 6, wherein a width W of the thin portion in a radial direction of the hole is 2.0 to 3.0 mm.   The foamed molded product for a seat pad according to any one of claims 4 to 7, wherein an opening shape of the hole is a circular shape or an elliptical shape.   In any one of Claims 4 thru | or 8, the surface by the side of the said seating person facing side of the said burr | flash part is a substantially flat surface which is flush with the said thick part from the said thin part. Foam molded body for seat pad.   A seat pad manufacturing method for manufacturing a seat pad by removing the burr part from the foam molded body for a seat pad according to any one of claims 1 to 9.   The seat pad manufacturing method according to claim 10, wherein the burr is removed by pressing the burr through the hole.

Images