JPH07108540B2 - Method for manufacturing resin molded products - Google Patents

Method for manufacturing resin molded products

Info

Publication number
JPH07108540B2
JPH07108540B2 JP3242129A JP24212991A JPH07108540B2 JP H07108540 B2 JPH07108540 B2 JP H07108540B2 JP 3242129 A JP3242129 A JP 3242129A JP 24212991 A JP24212991 A JP 24212991A JP H07108540 B2 JPH07108540 B2 JP H07108540B2
Authority
JP
Japan
Prior art keywords
core body
resin
skin layer
cavity
mold
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
JP3242129A
Other languages
Japanese (ja)
Other versions
JPH0577278A (en
Inventor
和弘 金子
嘉則 後藤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nihon Plast Co Ltd
Original Assignee
Nihon Plast Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nihon Plast Co Ltd filed Critical Nihon Plast Co Ltd
Priority to JP3242129A priority Critical patent/JPH07108540B2/en
Publication of JPH0577278A publication Critical patent/JPH0577278A/en
Publication of JPH07108540B2 publication Critical patent/JPH07108540B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Landscapes

  • Air Bags (AREA)
  • Injection Moulding Of Plastics Or The Like (AREA)

Abstract

PURPOSE:To prevent the inflow of the resin of a skin layer onto the rear of a core body and the deformation of the core body by mounting the core body, from an outer circumferential section of which a holding piece protrudes, to the cavity of split molds, holding the holding piece by the periphery of the cavity and injecting a resin to the surface side of the core body when the skin layer is formed to the core body made of the resin by the resin. CONSTITUTION:When a cover body covering the air bag of an automobile is manufactured, a core body 32 made of a rigid resin is molded first. A core body 31 has a plate section 31 and a leg section 30. A side face section 41 is formed to the peripheral section of the plate section 31, and a holding piece having an L-shaped cross section protrudes from the lower side of the outer circumferential section of the side face section 41. When the core body 32 is installed and a mold 45 is clamped, a cavity 51 is formed on the surface side of the core body 32 while the holding piece 43 is fast stuck to and held by a parting surface 54. A resin is injected into the cavity 51 and a skin layer 33 is formed, the mold is released, and the holding piece 43 is cut and removed. Accordingly, the resin shaping the skin layer 33 does not intrude to the rear of the core body 32, and the deformation of the core body 32 is also prevented.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、芯体の表面上に表皮層
を形成する二層成形の樹脂成形品の製造方法に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a two-layer molded resin molded product in which a skin layer is formed on the surface of a core.

【0002】[0002]

【従来の技術】例えば、自動車において、乗員を衝突時
の衝撃から保護するエアバッグは、通常は折畳まれた状
態でステアリングホイールのボス部などに収納され、合
成樹脂製のカバー体により覆われている。そして、この
エアバッグは、衝突などの際にガスの流入により展開し
て膨脹し、この膨脹の圧力によりカバー体を破断させ、
乗員に向かって突出するようになっている。
2. Description of the Related Art For example, in an automobile, an airbag that protects an occupant from a collision is normally stored in a folded state in a boss portion of a steering wheel and covered with a synthetic resin cover. ing. Then, this airbag expands and inflates due to the inflow of gas in the event of a collision, and the cover body is broken by the pressure of this inflation,
It is designed to project toward the occupant.

【0003】このようなエアバッグを覆うカバー体にお
いては、安全性をさらに向上するとともに、外観性およ
び触感などを向上するため、例えば特開昭63−199
149号公報に示されるように、硬質合成樹脂からなる
芯体の表面に、軟質合成樹脂からなる表皮層を密着して
形成した、二層成形の樹脂成形品が用いられている。
In order to further improve the safety and the appearance and feel of the cover body for covering such an air bag, for example, JP-A-63-199 is used.
As shown in Japanese Patent Publication No. 149, a double-layer molded resin molded product is used in which a skin layer made of a soft synthetic resin is formed in close contact with the surface of a core made of a hard synthetic resin.

【0004】そして、従来、このような二層成形の樹脂
成形品の製造方法においては、芯体を成形した後にこの
芯体を一旦金型から取外し、この芯体をあらためて表皮
層成形用の金型に装着して型締し、キャビティ内に合成
樹脂を注入してこの芯体の表面上に表皮層を密着成形す
る、いわゆるインサート成形による方法と、芯体を成形
した後に、表面側の金型のみを表皮層成形用の金型に交
換して型締し、キャビティ内に合成樹脂を注入して表皮
層を成形する、いわゆる2色成形(ダブルインジェクシ
ョン)による方法とが知られている。
In the conventional method for producing a two-layer-molded resin molded product, after molding the core, the core is once removed from the mold, and the core is newly re-molded for forming the skin layer. It is mounted on a mold, clamped, and a synthetic resin is injected into the cavity to form a skin layer on the surface of this core body by contact molding. There is known a method of so-called two-color molding (double injection), in which only the mold is replaced with a mold for molding a skin layer, the mold is clamped, and a synthetic resin is injected into the cavity to mold the skin layer.

【0005】[0005]

【発明が解決しようとする課題】しかしながら、上記従
来のダブルインジェクションやインサート成形による方
法では、表皮層成形時の熱や圧力によって芯体に変形が
生じやすく、外観性が損なわれるとの問題を有してい
る。これを防止するために、芯体に十分な強度を与えな
ければならないから、芯体を厚肉に成形する必要があ
り、重量の増加とコストアップなどの問題も有してい
る。更に、表皮層成形時の熱や圧力により変形が生じる
と、金型と芯体との間に間隙が生じたり、あるいは、イ
ンサート成形による収縮後の芯体の形状はそれぞれ個々
の芯体により変化するため、これらの芯体は表皮層成形
用の金型に完全に密着しない場合があり、金型と芯体と
の間に不必要な間隙が発生し、これにより表皮層を形成
する樹脂が芯体の裏面側に流入するのであるから、品質
が低下し、歩留りが悪く生産性が低いとの問題を有して
いる。
However, the above-mentioned conventional methods of double injection and insert molding have a problem that the core body is apt to be deformed by heat and pressure during the molding of the skin layer and the appearance is impaired. is doing. In order to prevent this, it is necessary to give sufficient strength to the core body, so it is necessary to mold the core body to a thick wall, and there are problems such as an increase in weight and an increase in cost. Furthermore, if deformation occurs due to heat or pressure during molding of the skin layer, a gap may be created between the mold and the core, or the shape of the core after shrinkage due to insert molding may change depending on the individual core. Therefore, these cores may not be completely adhered to the mold for forming the skin layer, and an unnecessary gap is generated between the mold and the core, whereby the resin forming the skin layer is not formed. Since it flows into the back side of the core, there is a problem that the quality is deteriorated, the yield is poor, and the productivity is low.

【0006】本発明は、このような点に鑑みなされたも
ので、芯体の表面上に表皮層を形成する二層成形の樹脂
成形品の製造方法において、表皮層を形成する樹脂が芯
体の裏面側へ流入することを防止し得るとともに、樹脂
成形品の外観性も良好とし、高品質の成形品を得ること
ができる樹脂成形品の製造方法を提供することを目的と
する。
The present invention has been made in view of the above circumstances, and in a method for producing a two-layer molded resin molded article in which a skin layer is formed on the surface of a core body, the resin forming the skin layer is a core body. It is an object of the present invention to provide a method for producing a resin molded product, which can prevent the resin molded product from flowing into the back surface side of the resin and also can improve the appearance of the resin molded product, and can obtain a high quality molded product.

【0007】[0007]

【課題を解決するための手段】本発明の樹脂成形品の製
造方法は、樹脂にて形成された芯体32の表面上に樹脂に
て表皮層33を形成する二層成形の樹脂成形品5の製造方
法において、前記芯体32には、外周部に挾持片43を突設
し、この芯体32を前記表皮層33成形用の割金型46,48の
キャビティ51に装着し、これらの割金型46,48を型締
し、前記キャビティ51の周辺部にて前記挾持片43を密着
挾持した状態で、前記キャビティ51内の前記芯体32の表
面側に樹脂を注入し前記表皮層33を形成するものであ
る。
According to the method of manufacturing a resin molded product of the present invention, a resin molded product 5 of two-layer molding in which a skin layer 33 is formed of resin on the surface of a core body 32 formed of resin. In the manufacturing method, the core body 32 is provided with a holding piece 43 projecting from the outer peripheral portion thereof, and the core body 32 is attached to the cavities 51 of the split molds 46 and 48 for molding the skin layer 33. In a state where the split molds 46 and 48 are clamped and the holding piece 43 is closely held in the peripheral portion of the cavity 51, a resin is injected into the surface side of the core body 32 in the cavity 51 to form the skin layer. To form 33.

【0008】[0008]

【作用】本発明の樹脂成形品の製造方法は、芯体32の外
周部に挾持片43を突設し、この挾持片43を割金型46,48
のキャビティ51の周辺部にて密着挾持した状態で、樹脂
を注入し、表皮層33を前記キャビティ51内に形成するた
め、キャビティ51に注入される表皮層33を形成する樹脂
が芯体32の裏面側に侵入することが防止され、芯体32の
表面側のみに表皮層33が形成される。また、表皮層33の
成形時に、割金型46,48で芯体32の挾持片43を挾持して
保持するため、表皮層33を形成する樹脂の圧力や熱によ
る、芯体32の変形が防止される。
According to the method for manufacturing a resin molded product of the present invention, the holding piece 43 is provided on the outer peripheral portion of the core body 32, and the holding piece 43 is used for the split molds 46, 48.
In order to form a skin layer 33 in the cavity 51 by injecting a resin in a state where the resin is in close contact with the periphery of the cavity 51, the resin forming the skin layer 33 injected into the cavity 51 is the core 32. The back surface side is prevented from entering, and the skin layer 33 is formed only on the front surface side of the core body 32. Further, since the sandwiching pieces 43 of the core body 32 are clamped and held by the split molds 46 and 48 when the skin layer 33 is formed, the core body 32 is not deformed by the pressure or heat of the resin forming the skin layer 33. To be prevented.

【0009】[0009]

【実施例】以下、本発明の樹脂成形品の製造方法の一実
施例の構成を図面を参照して説明する。
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of an embodiment of the method for producing a resin molded product of the present invention will be described below with reference to the drawings.

【0010】この実施例では、樹脂成形品として、自動
車のエアバッグを覆うカバー体の製造方法を示す。
In this embodiment, as a resin molded product, a method of manufacturing a cover body for covering an automobile airbag will be described.

【0011】図2において、1は自動車のステアリング
ホイール本体で、このステアリングホイール本体1は、
中央部のボス部2と円環状のリム部3とが複数個のスポ
ーク部4にて連結され、このボス部2の上部は樹脂成形
品としてのカバー体5にて覆われている。
In FIG. 2, reference numeral 1 is a steering wheel body of an automobile, and this steering wheel body 1 is
The central boss portion 2 and the annular rim portion 3 are connected by a plurality of spoke portions 4, and the upper portion of the boss portion 2 is covered with a cover body 5 as a resin molded product.

【0012】また、図3に示すように、このボス部2
は、図示しない自動車のステアリングシャフトに嵌着固
定される筒状の金属ボス11を有し、この金属ボス11の上
部に金属製のボスプレート12が溶接などにより固定され
ている。
Further, as shown in FIG.
Has a tubular metal boss 11 which is fitted and fixed to a steering shaft of an automobile (not shown), and a metal boss plate 12 is fixed to the upper portion of the metal boss 11 by welding or the like.

【0013】また、15はエアバッグ装置であり、このエ
アバッグ装置15は、下部を開口した略箱形状のベースプ
レート16を有し、このベースプレート16を図示しない取
付け手段を介してボスプレート12に固定することによ
り、ボスプレート12の上部に取付けられている。そし
て、このベースプレート16の略中央部には略円形の開口
部17が形成されており、この開口部17に、上方にガスを
噴出する略円筒形状のガス発生機18が取付けられている
とともに、ベースプレート16の上面の開口部17の周辺部
に、折り畳まれたエアバッグ21の円形の開口部22が固定
板23などにより固定されている。
Numeral 15 is an air bag device, which has a substantially box-shaped base plate 16 having an opening at the bottom, and the base plate 16 is fixed to the boss plate 12 through a mounting means (not shown). By doing so, it is attached to the upper part of the boss plate 12. Then, a substantially circular opening 17 is formed at a substantially central portion of the base plate 16, and a substantially cylindrical gas generator 18 for ejecting gas upward is attached to the opening 17, and A circular opening 22 of the folded airbag 21 is fixed to a peripheral portion of the opening 17 on the upper surface of the base plate 16 by a fixing plate 23 or the like.

【0014】さらに、上記のベースプレート16の側面部
24に、カバー体5の裏面側に突設された脚部30がリベッ
ト25などにより固定されている。
Further, the side surface portion of the base plate 16 described above.
A leg portion 30 protruding from the back surface side of the cover body 5 is fixed to the cover 24 by a rivet 25 or the like.

【0015】このカバー体5は、上記のベースプレート
16の側面部24を取囲むように形成された複数枚の板状の
脚部30と、ボス部2の上部を覆う平板部31とが硬質合成
樹脂にて一体的に成形されて芯体32とされ、さらに、こ
の平板部31の表面上に、発泡熱可塑性ポリウレタンエラ
ストマーなどの軟質合成樹脂からなる表皮層33が密着し
て成形されている。また、各脚部30には、リベット25が
挿通する通孔34がそれぞれ形成されている。
The cover body 5 is the above-mentioned base plate.
A plurality of plate-like leg portions 30 formed so as to surround the side surface portion 16 of 16 and a flat plate portion 31 that covers the upper portion of the boss portion 2 are integrally molded with a hard synthetic resin to form a core body 32. Further, on the surface of the flat plate portion 31, a skin layer 33 made of a soft synthetic resin such as foamed thermoplastic polyurethane elastomer is adhered and formed. Further, each leg 30 is formed with a through hole 34 through which the rivet 25 is inserted.

【0016】また、この平板部31の裏面側には、断面略
U字状または断面略V字状などに凹設された薄肉部35
が、ほぼH字形状を成して、平板部31の中央部を通る左
右方向と平板部31の両側部を通る前後方向に形成されて
いる。
Further, on the back surface side of the flat plate portion 31, a thin-walled portion 35 recessed in a substantially U-shaped section or a substantially V-shaped section is provided.
However, it has a substantially H shape and is formed in the left-right direction passing through the central portion of the flat plate portion 31 and in the front-back direction passing both side portions of the flat plate portion 31.

【0017】そうして、このような構成により、自動車
の衝突事故などの場合、図示しない衝撃感知センサが作
動して、ガス発生機18からエアバッグ21の内部にガスを
急激に放出し、このガスにより、エアバッグ21を急激に
膨脹させる。そしてこのエアバッグ21が、その膨脹途中
に、その膨脹圧力によってカバー体5の薄肉部35を破断
してカバー体5を扉状に開口し、エアバッグ21がカバー
体5から突出して運転者に向かって展開する。そして、
この展開したエアバッグ21によって運転者がステアリン
グホイール1や前方のガラスに衝突するのを防止すると
ともに、衝突の際の衝撃を吸収する。
With such a structure, in the event of a vehicle collision, a shock sensor (not shown) is activated to rapidly release gas from the gas generator 18 to the inside of the airbag 21. The gas causes the airbag 21 to inflate rapidly. During the inflation, the airbag 21 breaks the thin portion 35 of the cover body 5 by the inflation pressure to open the cover body 5 into a door shape, and the airbag 21 projects from the cover body 5 to the driver. Expand towards. And
The inflated airbag 21 prevents the driver from colliding with the steering wheel 1 and the front glass, and absorbs the impact at the time of the collision.

【0018】次に、上記のカバー体5の製造方法を図面
を参照して説明する。
Next, a method of manufacturing the cover body 5 will be described with reference to the drawings.

【0019】まず、射出成形などにより、図4に示すよ
うな、硬質合成樹脂製の芯体32を形成する。この芯体32
は、上記のように、ステアリングホイール1のボス部2
を覆う平板部31と、この平板部31の裏面側からほぼ垂直
状に突設された各脚部30とが一体的に成形されていると
ともに、この平板部31の裏面側には、断面略U字状に凹
設された薄肉部35が、ほぼH字形状を成して形成されて
いる。
First, a core body 32 made of a hard synthetic resin as shown in FIG. 4 is formed by injection molding or the like. This core 32
Is the boss portion 2 of the steering wheel 1 as described above.
A flat plate portion 31 that covers the flat plate portion 31 and each leg portion 30 that projects substantially vertically from the back surface side of the flat plate portion 31 are integrally formed, and the back surface side of the flat plate portion 31 has a substantially cross-sectional shape. A thin portion 35 that is recessed in a U shape is formed in a substantially H shape.

【0020】また、この平板部31の周辺部は、スポーク
部4に接続する部分を除いて、ボス部2の側面部を覆う
ように、裏面側に向かって折り曲げられ側面部41が形成
されており、さらに、この側面部41の外周部は、肉薄に
下側に突設されたうえ外側に折り曲げられ、断面略L字
形状の挾持片43が形成されている。
The peripheral portion of the flat plate portion 31 is bent toward the rear surface to form a side surface portion 41 so as to cover the side surface portion of the boss portion 2 except for the portion connected to the spoke portion 4. Further, the outer peripheral portion of the side surface portion 41 is thinly provided so as to project downward and is bent outward, so that a holding piece 43 having a substantially L-shaped cross section is formed.

【0021】そして、この芯体32を、図1に示すよう
な、表皮層33成形用の金型45に装着する。この金型45
は、芯体32の裏面側を固定する割金型としての下金型46
と、キャビティ面47を有する割金型としての上金型48と
からなっている。また、芯体32をこの金型45に装着し、
下金型46と上金型48とを型合、型締した状態で、芯体32
の表面側と上金型48のキャビティ面47との間に、表皮層
33を形成するキャビティ51が形成されるとともに、下金
型46と上金型48とのキャビティ51の周縁部のパーティン
グ面54で芯体32の挾持片43を密着挾持するようになって
いる。また、この密着性を高めるため、下金型46のパー
ティング面54には、挾持片43の形状に合わせた凹部55が
形成されている。
Then, the core body 32 is mounted on a mold 45 for molding the skin layer 33 as shown in FIG. This mold 45
Is a lower mold 46 as a split mold for fixing the back side of the core 32.
And an upper die 48 as a split die having a cavity surface 47. Also, attach the core body 32 to this mold 45,
With the lower mold 46 and the upper mold 48 mated and clamped, the core 32
Between the surface side of the upper surface of the mold and the cavity surface 47 of the upper mold 48.
A cavity 51 that forms 33 is formed, and the holding piece 43 of the core 32 is closely held by the parting surface 54 of the lower mold 46 and the upper mold 48 at the peripheral edge of the cavity 51. . Further, in order to enhance the adhesion, a recess 55 matching the shape of the holding piece 43 is formed on the parting surface 54 of the lower mold 46.

【0022】そして、上記のように型締した状態で、キ
ャビティ51内に、ポリウレタンなどの合成樹脂液を射出
し、表皮層33を芯体32の表面上に射出成形する。
Then, with the mold clamped as described above, a synthetic resin liquid such as polyurethane is injected into the cavity 51, and the skin layer 33 is injection-molded on the surface of the core body 32.

【0023】また、この表皮層33は、成形直前に例え
ば、ポリウレタンにおけるイソシアネート、ポリオール
及び触媒などを混合して射出する反応射出成形、すなわ
ちRIM(Reaction Injection Molding)成形によ
ることもできる。
The skin layer 33 can also be formed by reaction injection molding, that is, RIM (Reaction Injection Molding) molding in which, for example, isocyanate, polyol and catalyst in polyurethane are mixed and injected immediately before molding.

【0024】そして、この表皮層33の成形後、型開きし
てカバー体5を取出し、さらに断面略L字形状の挾持片
43を、熱刃、あるいはプレス刃にて切断して除去し、二
層成形のカバー体5を完成する。
After forming the skin layer 33, the mold is opened to take out the cover body 5, and the holding piece having a substantially L-shaped cross section is further provided.
43 is removed by cutting with a hot blade or a press blade, and the cover body 5 of two-layer molding is completed.

【0025】なお、この挾持片43の切除時に、挾持片43
に密着した図示しない成形用のゲート、インモールドコ
ート、ウレタンオーバーフローなどの余部を同時に切除
することもできる。
When the holding piece 43 is removed, the holding piece 43 is removed.
It is also possible to simultaneously remove the surplus portion such as a molding gate, an in-mold coat, and a urethane overflow, which are not shown and which are in close contact with.

【0026】そうして、本実施例の樹脂成形品の製造方
法によれば、表皮層33の射出成形時に、下金型46と上金
型48とのキャビティ51の周縁部のパーティング面54で芯
体32に形成された挾持片43を密着挾持するため、表皮層
33を形成する樹脂が芯体32の裏面側の、特に薄肉部35に
侵入することを防止し、芯体32の表面側のみに表皮層33
を形成することができる。そこで、品質を向上し、コス
トダウンを図り得るとともに、カバー体5を軽量化し、
取付け構造の簡易化、エアバッグ21の展開性能のいっそ
うの向上、安定などを図ることができる。
Thus, according to the method for manufacturing a resin molded product of the present embodiment, the parting surface 54 at the peripheral edge of the cavity 51 between the lower mold 46 and the upper mold 48 during injection molding of the skin layer 33. The gripping piece 43 formed on the core body 32 is firmly held by the skin layer.
The resin forming 33 is prevented from entering the back surface side of the core body 32, particularly the thin portion 35, and the skin layer 33 is formed only on the front surface side of the core body 32.
Can be formed. Therefore, the quality can be improved and the cost can be reduced, and the weight of the cover body 5 can be reduced.
It is possible to simplify the mounting structure, further improve the deployment performance of the airbag 21, and stabilize the airbag.

【0027】また、表皮層33の射出成形時に、下金型46
と上金型48とで芯体32の挾持片43を挾持して保持してい
るので、表皮層33を形成する樹脂の圧力や熱による、芯
体32の波打ち等の変形を防止することができ、均一な厚
さにすることができる。また、このために、芯体32の肉
薄化を図ることもできる。
Further, at the time of injection molding of the skin layer 33, the lower mold 46
Since the sandwiching piece 43 of the core body 32 is sandwiched and held by the upper mold 48 and the upper die 48, it is possible to prevent the core body 32 from being deformed due to pressure or heat of the resin forming the skin layer 33, such as waviness. The thickness can be made uniform. Further, for this reason, the core 32 can be thinned.

【0028】なお、本実施例においては、一対の下金型
46と上金型48とで金型45を形成したが、図5および図6
に示すように、下金型46と上金型48とのパーティング面
54に、側方に移動する複数個のスライド駒58を組み合わ
せることもできる。このスライド駒58は、型締した状態
で挾持片43の上面および表皮層33の端部に密着するた
め、表皮層33を肉厚に形成した場合でも、挾持片43に対
する密着性を保持して合成樹脂液の流出を防止し得ると
ともに、カバー体5と金型45との離型性を向上すること
ができる。
In this embodiment, a pair of lower molds
The mold 45 was formed by 46 and the upper mold 48.
As shown in, the parting surface of the lower mold 46 and the upper mold 48
It is also possible to combine a plurality of slide pieces 58 that move laterally with 54. Since this slide piece 58 adheres to the upper surface of the sandwiching piece 43 and the end of the skin layer 33 in a clamped state, even if the skin layer 33 is formed to be thick, the slide piece 58 retains the adhesion to the sandwiching piece 43. It is possible to prevent the synthetic resin liquid from flowing out, and improve the releasability between the cover body 5 and the mold 45.

【0029】また、図7に示すように、シリコンなどの
弾性体からなる駒体59を上金型48の、挾持片43への密着
部に取付けることによっても、この駒体59が弾性変形す
ることにより、挾持片43に対する密着性を向上し得ると
ともに、カバー体5と金型45との離型性を向上すること
ができる。
Further, as shown in FIG. 7, when the piece 59 made of an elastic material such as silicon is attached to the close contact portion of the upper die 48 with the holding piece 43, the piece 59 is elastically deformed. As a result, the adhesion to the holding piece 43 can be improved, and the releasability between the cover body 5 and the mold 45 can be improved.

【0030】なお、挾持片43は芯体32の平板部31にも形
成することができる。
The holding piece 43 can also be formed on the flat plate portion 31 of the core body 32.

【0031】[0031]

【発明の効果】本発明の樹脂成形品の製造方法によれ
ば、芯体の外周部に挾持片を突設し、この挾持片を金型
のキャビティの周辺部にて密着挾持した状態で、表皮層
を前記キャビティ内に注入形成するため、キャビティに
注入される表皮層を形成する樹脂が芯体の裏面側に侵入
することを防止し、芯体の表面側のみに表皮層を形成す
ることができる。そこで、コストダウンを図り得るとと
もに、樹脂成形品を軽量化し、品質を向上させることが
できる。また、表皮層の成形時に、金型で芯体の挾持片
を挾持して保持するため、表皮層を形成する樹脂の圧力
や熱による、芯体の変形を防止することができ、均一な
厚さにすることができる。
According to the method for producing a resin molded product of the present invention, a holding piece is provided so as to project from the outer peripheral portion of the core body, and the holding piece is held in close contact with the periphery of the cavity of the mold. Since the skin layer is formed by injection into the cavity, the resin forming the skin layer injected into the cavity is prevented from entering the back surface side of the core body, and the skin layer is formed only on the front surface side of the core body. You can Therefore, it is possible to reduce the cost, reduce the weight of the resin molded product, and improve the quality. Further, when the skin layer is molded, the holding piece of the core body is held by being held by the mold, so that the core body can be prevented from being deformed due to the pressure or heat of the resin forming the skin layer, and the uniform thickness can be obtained. You can

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明の樹脂成形品の製造方法の一実施例を示
す作業工程図である。
FIG. 1 is a work process diagram showing an embodiment of a method for producing a resin molded product of the present invention.

【図2】同上樹脂成形品の製造方法の一実施例によるス
テアリングホイールの平面図である。
FIG. 2 is a plan view of a steering wheel according to an embodiment of the same method for manufacturing a resin molded product.

【図3】同上図2のステアリングホイールのA−A視断
面図である。
3 is a cross-sectional view of the steering wheel of FIG. 2 taken along line AA of FIG.

【図4】同上芯体の製造工程における裏面の斜視図であ
る。
FIG. 4 is a perspective view of the back surface in the manufacturing process of the same core body.

【図5】本発明の樹脂成形品の製造方法の他の実施例を
示す作業工程図である。
FIG. 5 is a work process diagram showing another embodiment of the method for producing a resin molded product of the present invention.

【図6】同上作業工程図である。FIG. 6 is a work process diagram of the above.

【図7】本発明の樹脂成形品の製造方法の他の実施例に
よる作業工程図である。
FIG. 7 is a working process diagram according to another embodiment of the method for producing a resin molded product of the present invention.

【符号の説明】[Explanation of symbols]

5 樹脂成形品としてのカバー体 32 芯体 33 表皮層 43 挾持片 46 割金型としての下金型 48 割金型としての上金型 51 キャビティ 5 Cover body as resin molding 32 Core body 33 Skin layer 43 Holding piece 46 Lower mold as split mold 48 Upper mold as split mold 51 Cavity

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 樹脂にて形成された芯体の表面上に樹脂
にて表皮層を形成する二層成形の樹脂成形品の製造方法
において、 前記芯体には、外周部に挾持片を突設し、 この芯体を前記表皮層成形用の割金型のキャビティに装
着し、 これらの割金型を型締し、前記キャビティの周辺部にて
前記挾持片を密着挾持した状態で、前記キャビティ内の
前記芯体の表面側に樹脂を注入し前記表皮層を形成する
ことを特徴とした樹脂成形品の製造方法。
1. A method for producing a two-layer molded resin molded product, wherein a skin layer is formed of a resin on the surface of a core body made of a resin. The core body is mounted in the cavity of the split mold for forming the skin layer, the split molds are clamped, and the sandwiching piece is closely held at the peripheral portion of the cavity. A method for producing a resin molded article, characterized in that a resin is injected into a surface side of the core body in a cavity to form the skin layer.
JP3242129A 1991-09-21 1991-09-21 Method for manufacturing resin molded products Expired - Lifetime JPH07108540B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3242129A JPH07108540B2 (en) 1991-09-21 1991-09-21 Method for manufacturing resin molded products

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3242129A JPH07108540B2 (en) 1991-09-21 1991-09-21 Method for manufacturing resin molded products

Publications (2)

Publication Number Publication Date
JPH0577278A JPH0577278A (en) 1993-03-30
JPH07108540B2 true JPH07108540B2 (en) 1995-11-22

Family

ID=17084740

Family Applications (1)

Application Number Title Priority Date Filing Date
JP3242129A Expired - Lifetime JPH07108540B2 (en) 1991-09-21 1991-09-21 Method for manufacturing resin molded products

Country Status (1)

Country Link
JP (1) JPH07108540B2 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996025308A1 (en) * 1995-02-14 1996-08-22 Winget, Larry, J. Unitary composite air bag cover and method of making same
JP3514013B2 (en) * 1995-11-27 2004-03-31 豊田合成株式会社 Mold for airbag cover
JP4890168B2 (en) * 2006-09-14 2012-03-07 日本プラスト株式会社 Mold for RIM molding of resin molded product and RIM molding method
JP5013990B2 (en) * 2007-06-28 2012-08-29 日本プラスト株式会社 Cover body of airbag device and airbag device

Also Published As

Publication number Publication date
JPH0577278A (en) 1993-03-30

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