JP6645898B2 - Manufacturing method of skin integral foam - Google Patents

Description

  The present invention relates to a method for producing a foam-integral skin product in which a foamed resin material is injected into a bag formed by sewing a plurality of skin pieces in a bag shape, and the foamed resin material is foamed and cured in the bag.

  Conventionally, in this type of method for producing a skin-integrated foam, a slit opening serving as an entrance and exit of a bag is formed between a pair of adjacent skin pieces, and a slit opening is formed in each of the pair of skin pieces. A tongue piece is known which protrudes from the edge of the bag to the inside of the bag body (for example, see Patent Document 1).

JP 2014-13697 A (Paragraphs [0022] to [0023], FIG. 4)

  By the way, in the above-described method for producing a skin-integrated foam product, for example, in order to spread the foamed resin throughout the bag body, the foaming mold is inclined when the foamed resin material is foamed and cured, and the slit opening is performed. Are arranged so that they face obliquely upward, and as a result, a pair of tongue pieces provided on a pair of skin pieces may be vertically stacked. However, when the bag body is arranged in this manner, the lower tongue piece rides on the upper tongue piece in the process of foaming and curing of the foamed resin raw material, and the slit opening flaps or the foamed resin from the slit opening. There has been a problem that molding defects occur due to leakage of raw materials.

  An object of the present invention is to provide a method for producing a skin-integrated foamed product that can suppress molding defects.

  In order to achieve the above object, the invention according to claim 1, wherein a plurality of skin pieces are sewn into a bag shape to form a bag body, and the bag body is interposed between a pair of adjacent skin pieces. A method for producing a skin-integrated foamed article, comprising forming a slit opening serving as an entrance and exit, injecting a foamed resin material from the slit opening, and foaming and curing the foamed resin material in the bag body, wherein the pair of skin pieces is provided. Is provided with a tongue piece projecting from the edge of the slit opening to the inside of the bag body, and when the foamed resin material is foamed and cured, the slit opening is opened obliquely upward. In the method for producing a skin-integrated foam product in which the bag body is arranged and the pair of tongue pieces are vertically stacked, the lower side of the pair of tongue pieces is used when the foamed resin material is foamed and hardened. The first tongue placed on the upper side Is a long and to keep the manufacturing method of the integral skin foam products than arranged as a second tongue.

  The invention according to claim 2 is the method according to claim 1, wherein the skin pieces have a foam sheet layer having a closed cell structure.

  ADVANTAGE OF THE INVENTION According to this invention, when hardening a foaming resin raw material, it is suppressed that the 1st tongue piece arrange | positioned at the lower side gets on the 2nd tongue piece arrange | positioned at the upper side, and it depends on a slit opening and foaming It is possible to suppress molding defects such as leakage of resin material.

  Particularly, when the skin piece has a foamed sheet layer having a closed cell structure as in the invention of claim 2, the rigidity of the skin piece is increased by the foamed sheet layer, and a pair of tongues is provided at the center of the slit opening. Even if the base end of the piece is easily separated, it is possible to prevent the first tongue arranged on the lower side from riding on the second tongue arranged on the upper side.

Perspective view of a headrest according to the first embodiment Side section view of headrest Perspective view of bag (A) View of the periphery of the slit opening of the bag from the outside, (B) View from the inside Plan view of a plurality of skin pieces constituting the skin material Sectional view of the foaming mold when urethane foam material is injected into the bag Cross section of foaming mold before foam hardening Sectional view of the foaming mold after foam hardening The figure which shows notionally the foaming process when a 1st tongue piece is the same length as a 2nd tongue piece. The figure which shows notably the foaming process when a 1st tongue piece is longer than a 2nd tongue piece. (A) Perspective view and (B) side sectional view of a headrest according to a second embodiment. Plan view of a plurality of skin pieces constituting the skin material Sectional view of the foaming mold when urethane foam material is injected into the bag Cross section of foaming mold before foam hardening Sectional view of the foaming mold after foam hardening

[First Embodiment]
Hereinafter, a first embodiment in which the present invention is applied to a method for manufacturing a headrest will be described with reference to FIGS. As shown in FIGS. 1 and 2, a headrest 10 of the present embodiment (corresponding to “skin-integrated foam” of the present invention) includes a headrest body 10 </ b> H and a stay 12. The stay 12 has a structure in which a portion near a top end of a pipe having a gate shape is bent forward, the top of the stay 12 including the bent portion is disposed in the headrest body 10H, and the leg 12A of the stay 12 is provided. , 12A protrude from the bottom of the headrest body 10H. The legs 12A of the stay 12 are fixed to the upper part of the rear seat 90R of the vehicle.

  As shown in FIG. 2, the headrest main body 10 </ b> H is configured such that a pad 15 formed of urethane foam is covered with a bag 20. The top of the stay 12 is buried in the pad 15. In the present embodiment, the pad 15 is formed in a substantially L-shape in a side view with a front end bent downward, and the bag body 20 is also formed in a substantially L-shape in a side view corresponding to the pad 15.

  The bag body 20 is formed by sewing a plurality of skin pieces 21 in a bag shape. FIG. 5 shows a plurality of skin pieces 21 constituting the bag body 20. The plurality of skin pieces 21 include an upper skin piece 21A forming the front surface, the upper surface, and the rear surface of the headrest body 10H, a lower front skin piece 21B forming a front portion of the lower surface of the headrest body 10H, and a lower surface piece of the headrest body 10H. It comprises a lower rear skin piece 21C constituting the rear part, and a pair of side skin pieces 21S, 21S constituting both side surfaces of the headrest main body 10H. Then, the bag body 20 is formed by overlapping and stitching the boundary portions of the plurality of skin pieces 21 together. Each skin piece 21 has a structure in which a surface material and a lining are bonded together, and a surface facing the inside of the bag body 20 is a lining. The outer material is formed of, for example, a fabric sheet, a synthetic leather sheet, a genuine leather sheet, or the like. The lining is formed of a foam sheet having a closed cell structure. In the example of the present embodiment, a polyethylene foam sheet is used as a backing.

  In detail, the sewing of the skin pieces 21 and 21 is as follows. That is, at the boundary portion between the adjacent skin pieces 21 and 21, the overlapping portions 25 and 25 where the outer materials of the skin pieces 21 and 21 are overlapped are provided. Then, the superimposed portions 25, 25 are sewn, whereby the skin pieces 21, 21 are sewn together.

  As shown in FIGS. 2 to 4, a slit opening 20 </ b> K extending in the left-right direction and serving as an entrance of the bag body 20 is formed in a portion of the bag body 20 that forms the lower surface of the headrest 10 </ b> H. The slit opening 20K is sealed with urethane foam constituting the pad 15. FIG. 3 shows the bag body 20 in a state where the slit opening 20K is widened.

  Specifically, the slit opening 20K is formed as follows. That is, the boundary between the lower front skin piece 21B and the lower rear skin piece 21C described above is disposed on the lower surface of the headrest main body 10H (see FIGS. 2 and 3), and the lower front skin piece 21B and the lower rear skin piece 21B. Only the left and right ends of the overlapping portions 25, 25 of the piece 21C are sewn (see FIG. 4B). Then, between the non-sewn portions of the overlapping portions 25, 25 of the lower front skin piece 21B and the lower rear skin piece 21C (that is, the middle part of the overlapping portions 25, 25 in the left-right direction) along the left-right direction. A slit opening 20K extending linearly is formed.

  As shown in FIGS. 4A and 4B, the bag body 20 is provided with a pair of tongue pieces 27, 27 protruding from the opening edge of the slit opening 20K to the inside of the bag body 20. . The pair of tongue pieces 27, 27 are formed by the non-sewn portions of the overlapping portions 25, 25 of the lower front skin piece 21B and the lower rear skin piece 21C, and are arranged so as to sandwich the slit opening 20K back and forth. ing. The protruding length of the first tongue piece 27A disposed on the front side of the pair of tongue pieces 27, 27 is longer than the protruding length of the second tongue piece 27B disposed on the rear side.

  The structure of the headrest 10 has been described above. Next, a method for manufacturing the headrest 10 will be described.

  To manufacture the headrest 10, first, a plurality of skin pieces 21 shown in FIG. 5 are prepared. Each of the skin pieces 21 has a structure in which the above-described overlapping portion 25 is provided outside an outer surface constituting portion 24 which is an outer surface of the headrest 10. Here, among the overlapping portions 25 of the lower front skin piece 21B and the lower rear skin piece 21C, the front overlapping portion 25B and the rear overlapping portion 25C arranged at the boundary between the skin pieces 21B and 21C are formed. Has a convex shape in which an intermediate portion in the left-right direction (the left-right direction of the headrest 10) protrudes away from the outer surface constituting portion 24 of each of the skin pieces 21B and 21C. Then, the projecting length of the central projecting portion 25T of the front overlapping portion 25B is longer than the projecting length of the central projecting portion 25T of the rear overlapping portion 25C.

  Next, the plurality of skin pieces 21 are sewn in a bag shape to form a bag body 20 with the lining of each skin piece 21 facing outward. Specifically, the overlapping portions 25 of the skin pieces 21 are overlapped so that the outer fabric faces each other and sewn to each other. At this time, between the front overlapping portion 25B and the rear overlapping portion 25C, the central projection 25T of the front overlapping portion 25B is overlapped so as to protrude toward the distal end side from the central projection 25T of the rear overlapping portion 25C. The left and right ends of the front overlapping portion 25B and the rear overlapping portion 25C are sewn (see FIG. 4B). Then, a linear slit opening 20K is formed between the non-sewn portions of the front overlapping portion 25B and the rear overlapping portion 25C (that is, the middle portion in the left-right direction of the overlapping portions 25, 25).

  Next, the bag body 20 is turned upside down using the slit opening 20K as a return opening. Then, the outer material of each skin piece 21 is arranged outside, and the bag body 20 shown in FIG. 3 is obtained. At this time, between the lower front skin piece 21B and the lower rear skin piece 21C, the non-sewn portions (specifically, the central projections 25T, 25T) of the front overlapping portion 25B and the rear overlapping portion 25C are provided. A pair of tongue pieces 27, 27 projecting from the opening edge of the slit opening 20K to the inside of the bag body 20 are formed. Here, as described above, the projecting length of the central protruding portion 25T of the front overlapping portion 25B is longer than the projecting length of the central protruding portion 25T of the rear overlapping portion 25C. Of the 27, 27, the first tongue piece 27A arranged on the front side is longer than the second tongue piece 27B arranged on the rear side.

  When the bag body 20 shown in FIG. 3 is obtained, the bag body 20 and the stay 12 are then set in the foaming mold 30 (see FIG. 6. In FIG. 6, the stay 12 is not shown). .). At this time, the bag body 20 is arranged so that the slit opening 20K faces directly above.

  In detail, the foaming mold 30 is a known mold used for skin-integral foam molding, and has, for example, a second lower mold 32 that is rotatable with respect to a first lower mold 31. A first upper die 33 and a second upper die 34 are rotatably provided above the first lower die 31 and the second lower die 32. The second lower mold 32 and the second upper mold 34 are provided with molding surfaces for molding the front portion of the headrest main body 10H, and the first lower mold 31 and the first upper mold 33 are provided behind the headrest main body 10H. A molding surface for molding the side portions is provided. In the state where the bag body 20 is set in the foaming mold 30, the boundary between the upper skin piece 21A and the lower rear skin piece 21C is on the boundary between the first lower mold 31 and the first upper mold 33. Are located. The first upper mold 33 is open so that the urethane foam material 35 can be injected into the bag body 20 (see FIG. 6). As will be described later, the foam molding die 30 is tilted after the injection of the urethane foam raw material 35, and at this time, the first upper mold 33 is disposed on the upper side.

  Next, as shown in FIG. 6, a nozzle 36 is inserted into the slit opening 20K, and a urethane foam material 35 (corresponding to the “foam resin material” of the present invention) is injected into the bag 20 from the nozzle 36.

  When the injection of the urethane foam raw material 35 is completed, as shown in FIG. 7, the nozzle 36 is retracted from the slit opening 20K, the foam molding die 30 is tilted so that the front end of the bag body 20 is lowered, and the first mold is tilted. The upper mold 33 is closed. Thereby, the front end portion of the bag body 20 having a substantially L shape in a side view is easily filled with urethane foam. In this state, the slit opening 20K is disposed so as to face diagonally upward and forward, and the second tongue 27B of the pair of tongues 27, 27 is overlaid on the first tongue 27A.

  Next, the urethane foam raw material 35 is foamed and hardened (see FIG. 8). Then, the pad 15 made of urethane foam is formed in the bag body 20. When the molded product is released from the foam molding die 30, the headrest 10 in which the bag body 20 and the pad 15 are integrated is obtained.

  The description of the structure and manufacturing method of the headrest 10 according to the present embodiment has been described above. Next, the operation and effect of the method for manufacturing the headrest 10 according to the present embodiment will be described.

  In the method of manufacturing the headrest 10 according to the present embodiment, the lower side of the pair of tongue pieces 27, 27 projecting from the opening edge of the slit opening 20K to the inside of the bag body 20 when the urethane foam raw material 35 is foamed and hardened. Is longer than the second tongue 27B disposed on the upper side. Therefore, when the urethane foam material 35 is cured, the lower end of the first tongue piece 27A is prevented from riding on the second tongue piece 27B, and the slit opening 20K fluctuates or the urethane foam material 35 from the slit opening 20K. This makes it possible to suppress molding defects such as leakage of molding.

  Hereinafter, the suppression of the first tongue piece 27A from climbing up in the present embodiment is presumed. Before that, first, based on FIGS. 9A to 9C, the first tongue piece 27A is connected to the second tongue piece 27A. Consider an event that occurs when the length is the same as the length of the tongue piece 27B. As shown in FIG. 9A, at the initial stage of foaming of the urethane foam raw material 35, the first tongue piece 27A is disposed below the second tongue piece 27B. Further, due to the rigidity of the skin piece 21, the base ends of the first tongue piece 27A and the second tongue piece 27B are arranged apart from each other so as to widen the slit opening 20K in the middle of the slit opening 20K. (This phenomenon is particularly noticeable when the lower front skin piece 21B and the lower rear skin piece 21C have a foam sheet layer having a closed cell structure, due to the rigidity of the skin pieces. ). Then, as the foaming progresses from the state shown in FIG. 9A, the urethane foam raw material 35 collides with the lower end of the first tongue piece 27A. Here, since the second tongue piece 27B is arranged above the lower end of the first tongue piece 27A, as shown in FIG. 9B, the first tongue piece 27A is formed by the urethane foam raw material 35. Is pushed up, the lower end of the first tongue piece 27A moves diagonally upward and forward along the second tongue piece 27B. Then, when the foaming further progresses from the state shown in FIG. 9B, the overlapping portion of the first tongue piece 27A and the second tongue piece 27B moves to the rear side of the headrest 10 at the intermediate portion of the slit opening 20K. I do. As a result, it is considered that the slit opening 20K is formed in a meandering shape at the middle part (the middle part of the headrest 10 in the left-right direction) (see FIG. 9C). Note that FIG. 9C shows the first tongue piece 27A and the second tongue piece when the lower end of the first tongue piece 27A does not move upward, that is, when the slit opening 20K does not meander. 27B is indicated by a two-dot chain line.

  Next, based on FIG. 10 (A) and FIG. 10 (B), it is inferred about an event that occurs in the case of the present embodiment, that is, when the first tongue piece 27A is longer than the second tongue piece 27B. As shown in FIG. 10A, also in the present embodiment, in the initial stage of foaming of the urethane foam raw material 35, the first tongue piece 27A is disposed below the second tongue piece 27B. Further, due to the rigidity of the skin piece 21, the base ends of the first tongue piece 27A and the second tongue piece 27B are arranged apart from each other so as to widen the slit opening 20K in the middle of the slit opening 20K. . When the foaming proceeds from the state shown in FIG. 10A, the urethane foam raw material 35 collides with the lower end of the first tongue piece 27A. Here, if the first tongue piece 27A is longer than the second tongue piece 27A, the second tongue piece 27B does not exist above the lower end of the first tongue piece 27A. When the lower end is lifted, the first tongue 27A is bent so that the lower end is directed upward, as shown in the change from FIG. 10 (A) to FIG. 10 (B), and the lower end of the first tongue 27A. The part does not move upward as shown in FIG. 9B. Thereby, it is supposed that the first tongue 27A is suppressed from being pushed up with respect to the second tongue 27B, and the climbing of the first tongue 27A is suppressed. Moreover, as shown in FIG. 10B, the first tongue 27B easily prevents the urethane foam raw material 35 in the middle of foaming from moving upward near the slit opening 20K, and is indicated by an arrow in FIG. As described above, the urethane foam raw material 35 easily turns to the back side of the second tongue piece 27B. As a result, it is presumed that the slit opening 20K between the first tongue piece 27A and the second tongue piece 27B is easily closed.

[Second embodiment]
Hereinafter, a second embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 11A, the headrest 10V of the present embodiment is fixed to an upper part of a front seat 90F of a vehicle. The headrest 10V has a headrest body 10H and a stay 12, as in the first embodiment, and the headrest body 10H has a structure in which the outside of the pad 15V is covered with a bag 20V (see FIG. 11B )reference). In the present embodiment, the pad 15V is flat in the front-rear direction and has a substantially triangular shape when viewed from the side, and the bag 20V has a shape corresponding to the pad 15V.

  The bag body 20V has a plurality of skin pieces 121 sewn in a bag shape, as in the first embodiment. The plurality of skin pieces 121 are a front skin piece 121A forming the front surface of the headrest body 10H, a rear skin piece 121B forming the rear surface of the headrest body 10H, and a lower front skin forming the front part of the lower surface of the headrest body 10H. A piece 121C, a lower rear skin piece 121D forming the rear part of the lower surface of the headrest body 10H, and a pair of side skin pieces 121S, 121S (see FIG. 12) forming the side surface of the headrest body 10H. Become. The boundary between the adjacent skin pieces 121 has the same structure as that of the first embodiment. That is, at the boundary portion between the adjacent skin pieces 121, 121, the overlapping portions 25, 25 where the outer materials of the skin pieces 121, 121 are overlapped are provided, and the overlapping portions 25, 25 are sewn. Thus, the skin pieces 121 are sewn together.

  Here, the overlapping portions 25, 25 of the lower front skin piece 121C and the lower rear skin piece 121D are sewn only at both ends in the left-right direction. Then, between the non-sewn portions of the overlapping portions 25, 25 of the lower front skin piece 121C and the lower rear skin piece 121D (that is, the middle portion of the overlapping portions 25, 25 in the left-right direction) along the left-right direction. A slit opening 20K extending linearly is formed. Note that, also in the present embodiment, the slit opening 20K is sealed with urethane foam constituting the pad 15.

  From the opening edge of the slit opening 20K, a pair of tongue pieces 127, 127 protrude toward the inside of the bag 20V. In the present embodiment, the projection length of the first tongue piece 127A arranged on the rear side of the pair of tongue pieces 127, 127 is longer than the projection length of the second tongue piece 127B arranged on the front side. Has become. The pair of tongue pieces 127, 127 are formed by the non-sewn portions of the overlapping portions 25, 25 of the lower front skin piece 121C and the lower rear skin piece 121D, and sandwich the slit opening 20K back and forth. Are located.

  The rest of the structure of the headrest 10V is the same as that of the headrest 10 of the first embodiment, and thus the same reference numerals are given and the description is omitted.

  Next, a method for manufacturing the headrest 10V will be described. To manufacture the headrest 10V, first, a plurality of skin pieces 121 shown in FIG. 12 are prepared. In addition, of the overlapping portions 25, 25 of the lower front skin piece 121C and the lower rear skin piece 121D, the front overlapping portion 25C and the rear overlapping portion 25D arranged at the boundary between the skin pieces 121C, 121D. Is a convex shape in which an intermediate portion in the left-right direction (the left-right direction in the headrest 10) protrudes away from the outer surface constituting portion 24 of each of the skin pieces 121C and 121D. Then, the projecting length of the central projecting portion 25T of the rear overlapping portion 25D is longer than the projecting length of the central projecting portion 25T of the front overlapping portion 25C.

  Next, in the same manner as in the first embodiment, the plurality of skin pieces 121 are sewn into a bag shape to form a bag body 20V with the lining of the skin piece 121 facing outward, and the bag body 20V is connected to the slit opening 20K. Is turned upside down as a return opening to form a bag 20V with the outer material of the skin piece 121 facing outward. At this time, the front overlap portion 25C of the lower front skin piece 121C and the rear overlap portion 25D of the lower rear skin piece 121D are sewn at both left and right ends, and are overlapped with the front overlap portion 25C. A linear slit opening 20K is formed between the non-stitched portions of the fitting portion 25D. Further, a slit is formed between the lower front skin piece 121C and the lower rear skin piece 121D by a non-sewn portion (more specifically, central projections 25T, 25T) of the front overlapping portion 25C and the rear overlapping portion 25D. A pair of tongue pieces 127, 127 projecting from the opening edge of the opening 20K to the inside of the bag 20V are formed.

  Next, the bag 20V and the stay 12 are set in a foaming mold 30V (see FIG. 13; in this figure, the stay 12 is omitted). At this time, the bag 20V is arranged such that the slit opening 20K faces diagonally upward (specifically, diagonally upward and rearward). Also, the second tongue piece 127B of the pair of tongue pieces 127, 127 is overlaid on the first tongue piece 127A. As the foaming mold 30V, a known mold is used as in the foaming mold 30 of the first embodiment. That is, the foaming mold 30V has a second lower mold 32V rotatable with respect to the first lower mold 31V. The first upper mold 31V and the upper part of the second lower mold 32V have a first upper mold. It has a structure in which a mold 33V and a second upper mold 34V are rotatably provided. The second lower mold 32V and the second upper mold 34V are provided with molding surfaces for molding the front part of the headrest main body 10H, and the first lower mold 31V and the first upper mold 33V are provided with the rear surface of the headrest main body 10H. A molding surface for molding the side portions is provided.

  Next, as shown in FIG. 13, the nozzle 36 is inserted through the slit opening 20K with the second upper mold 34V that presses, from above, a portion of the bag body 20V disposed above the slit opening 20K open, The urethane foam raw material 35 is injected from the nozzle 36 into the bag 20V. Then, the nozzle 36 is removed from the slit opening 20K, the second upper mold 34V is closed, and the urethane foam raw material 35 is foamed and hardened (see FIG. 14). Then, a pad 15V made of urethane foam is formed in the bag 20V (see FIG. 15). When the molded product is removed from the foam molding die 30, a headrest 10V in which the bag 20V and the pad 15V are integrated is obtained.

  The description of the structure and the manufacturing method of the headrest 10V according to the present embodiment has been described above. According to the present embodiment, it is possible to achieve the same effects as those of the first embodiment.

[Other embodiments]
The present invention is not limited to the above-described embodiments. For example, the following embodiments are also included in the technical scope of the present invention, and furthermore, other than the following, various modifications may be made without departing from the spirit of the present invention. It can be changed and implemented.

  (1) In the above embodiment, the "skin-integrated foam" of the present invention is the headrest 10, but may be, for example, an armrest, a seat cushion, a seat back, or the like.

  (2) The configuration of the second embodiment may be applied to the first embodiment. That is, when the bag 20 is set in the foaming mold 30, the urethane foam raw material 35 may be injected and foamed and hardened such that the slit opening 20K faces obliquely upward and forward.

  (3) The configuration of the first embodiment may be applied to the second embodiment. That is, the bag 20V is set in the foaming mold 30V so that the slit opening 20K faces upward, the urethane foam raw material 35 is injected into the bag 20V, and the foaming mold 30V is tilted. The bag 20V may be arranged so that the opening 20K faces obliquely upward and rearward.

10,10V headrest (skin integral foam)
15, 15V pad 20, 20V bag 20K Slit opening 21, 121 Skin piece 27, 127 Tongue piece 27A, 127A First tongue piece 27B, 127B Second tongue piece 35 Urethane foam material (foam resin material)

Claims (2)

A plurality of skin pieces are sewn into a bag shape to form a bag body, and a slit opening serving as an entrance and exit of the bag body is formed between a pair of adjacent skin pieces, and a foamed resin material is formed from the slit opening. A method for producing a skin-integrated foam product in which the foamed resin material is foamed and cured in the bag body,
Each of the pair of skin pieces is provided with a tongue piece projecting from the edge of the slit opening to the inside of the bag body,
When foaming and curing the foamed resin material, the bag body is arranged so that the slit opening opens obliquely upward, and a pair of the tongue pieces are vertically stacked. At
When the foamed resin material is foamed and hardened, the first tongue arranged on the lower side of the pair of tongues is longer than the second tongue arranged on the upper side. Production method.   The method for producing a skin-integrated foam according to claim 1, wherein the skin piece has a foam sheet layer having a closed cell structure.

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