JP3722263B2

JP3722263B2 - Joint structure of curved hollow body

Info

Publication number: JP3722263B2
Application number: JP10025499A
Authority: JP
Inventors: 家勝治道; 山卓士秋
Original assignee: Nissan Motor Co Ltd
Current assignee: Nissan Motor Co Ltd
Priority date: 1999-04-07
Filing date: 1999-04-07
Publication date: 2005-11-30
Anticipated expiration: 2019-04-07
Also published as: JP2000289114A

Description

【０００１】
【発明の属する技術分野】
本発明は、射出成形した半割樹脂成形体同士を接合して湾曲状中空体を形成する、すなわち、ＤＳＩ（ＤｉｅＳｌｉｄｅＩｎｊｅｃｔｉｏｎ）工法、あるいは、ＤＲＩ（ＤｉｅＲｏｔａｒｙＩｎｊｅｃｔｉｏｎ）工法を用いて、湾曲状中空体を形成するのに利用される湾曲状中空体の接合部構造に関するものである。
【０００２】
【従来の技術】
従来、図３に示すように、例えば、ＤＳＩ工法を用いて、インテークマニホールド５０のＵ字状をなすポート（湾曲状中空体）５１を形成する場合、このポート５１の内側（図示下側）はアンダーカットとなる都合上、ポート５１を構成する一方の半割樹脂成形体５２を射出成形する際には、主型で抜くことができないため、スライドコアＳＣによって型抜きを行うようになっている。
【０００３】
そして、一方の半割樹脂成形体５２とともにポート５１を構成する他方の半割樹脂成形体５３を平板状に射出成形し、一方の半割樹脂成形体５２と他方の半割樹脂成形体５３とを接合すると共に双方の間に設けた隙間５４に溶融樹脂５５を充填してポート５１を形成するようになっている。
【０００４】
このＤＳＩ工法に関しては、例えば、特公平７−７３８７４号に記載されている。
【０００５】
【発明が解決しようとする課題】
ところが、従来にあっては、スライドコアＳＣによって型抜きした一方の半割樹脂成形体５２と平板状に射出成形した他方の半割樹脂成形体５３とを接合するようにしているので、ポート５１の断面形状が蒲鉾切り口状となってしまい、このポート５１のシリンダヘッドフランジ５６が配置される一端側の断面形状およびサージタンク５７が配置される他端側の断面形状がいずれも略円形状をなしていることから、ポート５１の断面形状が略円形状→蒲鉾切り口状→略円形状と変化することとなり、したがって、ポート５１の中間部分での断面形状が蒲鉾切り口状となっていることが、吸気抵抗を増加させる原因になり得るという問題を有しており、この問題を解決することが従来の課題となっていた。
【０００６】
【発明の目的】
本発明は、上記した従来の課題に着目してなされたもので、射出成形した半割樹脂成形体同士を接合して湾曲状中空体を形成する場合において、湾曲状中空体の中空部の断面形状を略円形状とすることができ、湾曲状中空体をインテークマニホールドのポートとした場合には、吸気抵抗の増加を低く抑えることが可能である湾曲状中空体の接合部構造を提供することを目的としている。
【０００７】
【課題を解決するための手段】
本発明の請求項１に係わる湾曲状中空体の接合部構造は、射出成形した半割樹脂成形体同士を接合すると共に双方の間に設けた隙間に溶融樹脂を充填して形成される湾曲状中空体の接合部において、一方の半割樹脂成形体には、他方の半割樹脂成形体側を向く断面が円弧状をなす一方側中空部形成壁を設けると共に、他方の半割樹脂成形体には、一方側中空部形成壁とともに断面が略円形状の中空部を形成する他方側中空部形成壁を設け、一方側中空部形成壁に連続して他方の半割樹脂成形体側に延出しかつ互いに平行をなす一対の対向壁を設けてこの一対の対向壁間に他方側中空部形成壁を挿入することで一方側中空部形成壁とともに断面が略円形状の中空部を形成し、湾曲状中空体の接合部の少なくとも一部の断面で、他方側中空部形成壁の中空部側の円弧面全体を一対の対向壁間に入り込ませてある構成としたことを特徴としており、このような湾曲状中空体の接合部構造の構成を前述した従来の課題を解決するための手段としている。
【０００８】
本発明の請求項２に係わる湾曲状中空体の接合部構造は、一方側中空部形成壁に連続して設けた一対の対向壁の各先端部分と、他方側中空部形成壁における一対の対向壁間の外側に位置する部分との間に、溶融樹脂を充填する隙間を設けた構成としている。
【０００９】
本発明の請求項３に係わる湾曲状中空体の接合部構造は、一方の半割樹脂成形体の一対の対向壁に、一方側中空部形成壁に連続する段差部をそれぞれ設けると共に、他方の半割樹脂成形体の他方側中空部形成壁に、一方の半割樹脂成形体の段差部との係合部を設け、他方の半割樹脂成形体の他方側中空部形成壁は、一方の半割樹脂成形体の一対の対向壁間において係合部を一方の半割樹脂成形体の段差部にそれぞれ係合させた状態で一方側中空部形成壁とともに断面が略円形状の中空部を形成する構成としている。
【００１０】
本発明の請求項４に係わる湾曲状中空体の接合部構造は、他方側中空部形成壁の係合部が一方の半割樹脂成形体の段差部から離間するのを規制する規制手段を設けた構成とし、本発明の請求項５に係わる湾曲状中空体の接合部構造において、規制手段は、他方側中空部形成壁の係合部の先端に位置する断面楔状をなす突条と、一方の半割樹脂成形体の一方側中空部形成壁と段差部との間に位置して他方側中空部形成壁の突条と係止する溝とからなっている構成としている。
【００１１】
【発明の作用】
本発明の請求項１に係わる湾曲状中空体の接合部構造では、上記した構成としていることから、射出成形した半割樹脂成形体同士を接合して湾曲状中空体を形成すると、一方の半割樹脂成形体の断面が円弧状をなす一方側中空部形成壁と、他方の半割樹脂成形体の他方側中空部形成壁とにより、断面が略円形状の中空部が形成されることとなり、湾曲状中空体をインテークマニホールドのポートとした場合には、ポートの端部と中間部分との断面形状が大きく変化しないので、吸気抵抗の増加が低く抑えられることとなる。この際、一方側中空部形成壁に連続して設けた一対の対向壁間に他方側中空部形成壁が挿入され、湾曲状中空体の接合部の少なくとも一部の断面では、他方側中空部形成壁の中空部側の円弧面全体が一対の対向壁間に入り込んだ状態となるので、一方側中空部形成壁に連続する一対の対向壁と他方側中空部形成壁との重なり領域が広くなり、湾曲状中空体の剛性が高まるのに加えて、両半割樹脂成形体の間に設けた隙間に溶融樹脂を充填する際のシール性が向上することとなる。
【００１２】
本発明の請求項２に係わる湾曲状中空体の接合部構造では、請求項１に係わる湾曲状中空体の接合部構造と同様に、湾曲状中空体の剛性が高まるうえ、両半割樹脂成形体の間に設けた隙間に溶融樹脂を充填する際のシール性が向上することとなり、本発明の請求項３に係わる湾曲状中空体の接合部構造では、射出成形した半割樹脂成形体同士を接合して湾曲状中空体を形成すると、他方の半割樹脂成形体における他方側中空部形成壁の係合部が一方の半割樹脂成形体の段差部にそれぞれ係合するので、湾曲状中空体の剛性がより一層高まることとなる。
【００１３】
本発明の請求項４に係わる湾曲状中空体の接合部構造では、上記した構成としているので、他方の半割樹脂成形体の収縮によって他方側中空部形成壁の係合部が反り返って一方の半割樹脂成形体の段差部から離間することが規制手段により阻止されることから、一方側中空部形成壁に対して他方側中空部形成壁が滑らかに連続している状態が維持されるうえ、剛性が向上すると共に接合部の結合強度が増加することとなる。
【００１４】
本発明の請求項５に係わる湾曲状中空体の接合部構造では、上記した構成としていることから、簡単な構造で他方の半割樹脂成形体の収縮による他方側中空部形成壁の係合部の反り返りが阻止されることとなる。
【００１５】
【発明の効果】
本発明の請求項１に係わる湾曲状中空体の接合部構造では、上記した構成としたから、射出成形した半割樹脂成形体同士を接合して湾曲状中空体を形成すれば、断面略円形状の中空部を形成することができ、湾曲状中空体をインテークマニホールドのポートとした場合には、吸気抵抗の増加を低く抑えることが可能であり、この際、一方側中空部形成壁に連続する一対の対向壁と他方側中空部形成壁との重なり領域を広くすることができる分だけ、湾曲状中空体の剛性を増大させることが可能であると共に、両半割樹脂成形体間の溶融樹脂に対するシール性の向上を実現することができるという非常に優れた効果がもたらされる。
【００１６】
本発明の請求項２に係わる湾曲状中空体の接合部構造では、上記した構成としているので、請求項１に係わる湾曲状中空体の接合部構造と同様に、湾曲状中空体の剛性を高めることが可能であると共に、両半割樹脂成形体間の溶融樹脂に対するシール性をも高めることができ、本発明の請求項３に係わる湾曲状中空体の接合部構造では、上記した構成としたため、湾曲状中空体の剛性を大幅に高めることが可能であるという非常に優れた効果がもたらされる。
【００１７】
本発明の請求項４に係わる湾曲状中空体の接合部構造では、上記した構成としたため、一方側中空部形成壁と他方側中空部形成壁との滑らかな連続状態を維持することができるうえ、剛性のより一層の向上およびこれによる騒音や振動の低減を実現することができると共に接合部の結合強度の増加をも実現することが可能であり、本発明の請求項５に係わる湾曲状中空体の接合部構造では、上記した構成としたことから、他方の半割樹脂成形体の収縮による他方側中空部形成壁の係合部の反り返りを簡単な構造で防ぐことが可能であるという非常に優れた効果がもたらされる。
【００１８】
【実施例】
以下、本発明を図面に基づいて説明する。
【００１９】
図１は本発明に係わる湾曲状中空体の接合部構造の一実施例を示しており、この実施例では、湾曲状中空体がインテークマニホールドのポートである場合を示す。
【００２０】
図１（ａ）に示すように、インテークマニホールド１は、ＤＳＩ工法を用いて形成されたものであって、Ｕ字状をなすポート（湾曲状中空体）２の一端側にシリンダヘッドフランジ５を配置すると共に他端側にサージタンク６を配置した構成をなしており、ポート２は、射出成形した一方の半割樹脂成形体３と他方の半割樹脂成形体４とを接合してなっている。
【００２１】
一方の半割樹脂成形体３には、図１（ｂ）に示すように、他方の半割樹脂成形体４側を向く断面が円弧状をなす一方側中空部形成壁３１と、この一方側中空部形成壁３１に連続して他方の半割樹脂成形体４側に延出しかつ互いに平行をなす一対の対向壁３２，３２と、一対の対向壁３２，３２に位置して一方側中空部形成壁３１にそれぞれ連続する段差部３３，３３が設けてある。
【００２２】
他方の半割樹脂成形体４には、一方の半割樹脂成形体３の一対の対向壁３２，３２間に挿入されて一方側中空部形成壁３１とともに断面が略円形状の中空部２１を形成する他方側中空部形成壁４１が設けてある。この場合、接合部の少なくとも一部の断面において、他方側中空部形成壁４１の中空部２１側の円弧面全体を一対の対向壁３２，３２間に入り込ませてあり、この他方側中空部形成壁４１の図示両端は、一方の半割樹脂成形体３の段差部３３，３３との係合部４３，４３として形成してあって、他方側中空部形成壁４１は、一対の対向壁３２，３２間において係合部４３，４３を段差部３３，３３にそれぞれ係合させた状態で一方側中空部形成壁３１とともに中空部２１を形成するようになっている。
【００２３】
ポート２は、一方の半割樹脂成形体３の一対の対向壁３２，３２間に他方の半割樹脂成形体４の他方側中空部形成壁４１を挿入して、他方の半割樹脂成形体４の係合部４３，４３を一方の半割樹脂成形体３の段差部３３，３３にそれぞれ係合させて接合状態とした後、一方側中空部形成壁３１に連続する一対の対向壁３２，３２の各先端部分と、他方側中空部形成壁４１における一対の対向壁３２，３２間の外側に位置する部分との間にできる隙間２２に溶融樹脂７を充填することによって形成されるようになっており、この状態において、ポート２の内部には両中空部形成壁３１，４１によって断面略円形状の中空部２１が形成されることとなる。
【００２４】
したがって、上記した接合部構造を有するポート２では、中空部２１の断面形状がシリンダヘッドフランジ５が配置される一端側からサージタンク６が配置される他端側にかけて略円形状に保たれることから、すなわち、中空部２１の断面形状が大きく変化しないことから、吸気抵抗の増加が極めて低く抑えられることとなり、この際、一方側中空部形成壁３１に連続する一対の対向壁３２，３２間に他方側中空部形成壁４１が挿入されていて、接合部の断面では、他方側中空部形成壁４１の中空部２１側の円弧面全体が一対の対向壁３２，３２間に入り込んだ状態となっているので、一対の対向壁３２，３２と他方側中空部形成壁４１との重なり領域が広くなり、その分だけ、ポート２の剛性が高まると共に、両半割樹脂成形体３，４の間の隙間２２に溶融樹脂を充填する際のシール性が向上することとなり、加えて、このポート２の接合部において、他方の半割樹脂成形体４における他方側中空部形成壁４１の係合部４３，４３が一方の半割樹脂成形体３の段差部３３，３３にそれぞれ係合していることから、ポート２の剛性が大幅に高まることとなる。
【００２５】
図２は本発明に係わる湾曲状中空体の接合部構造の他の実施例を示しており、この実施例における湾曲状中空体の接合部構造が先の実施例における湾曲状中空体の接合部構造と異なるところは、ポート２Ａを構成する他方の半割樹脂成形体４Ａにおける他方側中空部形成壁４１の係合部４３が、一方の半割樹脂成形体３Ａの段差部３３から離間するのを規制する規制手段を設けた点にあり、他の構成は先の実施例と同じである。
【００２６】
この場合、規制手段は、他方側中空部形成壁４１の係合部４３の先端に位置する断面楔状をなす突条４４と、一方の半割樹脂成形体３Ａの一方側中空部形成壁３１と段差部３３との間に位置して他方側中空部形成壁４１の突条４４と係止する溝３４からなっている。
【００２７】
上記した接合部構造を有するポート２Ａでは、他方側中空部形成壁４１の突条４４と一方の半割樹脂成形体３Ａの溝３４とが互いに係止することから、他方側中空部形成壁４１の係合部４３が収縮により反り返って一方の半割樹脂成形体３Ａの段差部３３から離間することが阻止されるため、一方側中空部形成壁３１に対して他方側中空部形成壁４１が滑らかに連続している状態が維持されるうえ、剛性が向上すると共に接合部の結合強度が増加することとなる。
【００２８】
なお、上記した実施例では湾曲状中空体がインテークマニホールドのポートである場合を示したがこれに限定されるものではない。
【００２９】
また、本発明に係わる湾曲状中空体の接合部構造の詳細な構成は上記した実施例に限定されるものではない。
【図面の簡単な説明】
【図１】本発明に係わる湾曲状中空体の接合部構造の一実施例を示すインテークマニホールドの側面説明図（ａ）および図１（ａ）のＡ−Ａ線位置でのポートの断面説明図（ｂ）である。
【図２】本発明に係わる湾曲状中空体の接合部構造の他の実施例を示す図１（ａ）のＡ−Ａ線相当位置でのポートの断面説明図である。
【図３】従来における湾曲状中空体の接合部構造を示すインテークマニホールドの側面説明図（ａ）および図３（ａ）のＢ−Ｂ線位置でのポートの断面説明図（ｂ）である。
【符号の説明】
２，２Ａポート（湾曲状中空体）
３，３Ａ一方の半割樹脂成形体
４，４Ａ他方の半割樹脂成形体
７溶融樹脂
２１中空部
２２隙間
３１一方側中空部形成壁
３２一対の対向壁
３３段差部
３４溝（規制手段）
４１他方側中空部形成壁
４３係合部
４４突条（規制手段）[0001]
BACKGROUND OF THE INVENTION
The present invention joins injection molded halved resin molded bodies to form a curved hollow body, that is, using a DSI (Die Slide Injection) method or a DRI (Die Rotary Injection) method, The present invention relates to a joint structure of a curved hollow body used for forming a hollow body.
[0002]
[Prior art]
Conventionally, as shown in FIG. 3, for example, when the U-shaped port (curved hollow body) 51 of the intake manifold 50 is formed using the DSI method, the inner side (the lower side in the drawing) of the port 51 is For the purpose of undercutting, when one of the half-shaped resin molded bodies 52 constituting the port 51 is injection-molded, it cannot be removed by the main mold, so that the die is cut by the slide core SC. .
[0003]
Then, the other half resin molded body 53 constituting the port 51 together with one half resin molded body 52 is injection-molded into a flat plate shape, and one half resin molded body 52 and the other half resin molded body 53 are And a port 54 is formed by filling a gap 54 provided between the two with a molten resin 55.
[0004]
This DSI method is described in, for example, Japanese Patent Publication No. 7-73874.
[0005]
[Problems to be solved by the invention]
However, in the prior art, one half-resin molded body 52 die-cut by the slide core SC and the other half-resin molded body 53 injection-molded into a flat plate shape are joined together. The cross-sectional shape of the one end side where the cylinder head flange 56 of the port 51 is disposed and the cross-sectional shape of the other end side where the surge tank 57 is disposed are both substantially circular. Therefore, the cross-sectional shape of the port 51 changes from a substantially circular shape to a cut-out shape → a substantially circular shape. Therefore, the cross-sectional shape at the intermediate portion of the port 51 is a cut-out shape. However, there is a problem that it may cause an increase in the intake resistance, and it has been a conventional problem to solve this problem.
[0006]
OBJECT OF THE INVENTION
The present invention has been made paying attention to the above-described conventional problems, and in the case of forming a curved hollow body by joining injection molded halved resin molded bodies, a cross section of a hollow portion of the curved hollow body To provide a joint structure of a curved hollow body that can be formed into a substantially circular shape and can suppress an increase in intake resistance when the curved hollow body is a port of an intake manifold. It is an object.
[0007]
[Means for Solving the Problems]
The curved hollow body joint structure according to claim 1 of the present invention is a curved shape formed by joining injection-molded halved resin molded bodies and filling a gap between them with molten resin. In the joint portion of the hollow body, one half-resin molded body is provided with a one-side hollow portion forming wall whose cross section facing the other half-resin molded body side forms an arc shape, Is provided with the other side hollow part forming wall that forms a hollow part having a substantially circular cross section together with the one side hollow part forming wall, and extends to the other half-resin molded body side continuously to the one side hollow part forming wall; By providing a pair of opposing walls parallel to each other and inserting the other-side hollow portion forming wall between the pair of opposing walls, a hollow portion having a substantially circular cross section is formed together with the one-side hollow portion forming wall. Formation of the other-side hollow part in the cross section of at least a part of the joint part of the hollow body The entire arcuate surface of the hollow portion has a feature that it has a configuration are allowed to enter the pair of opposing walls, solve the conventional problems described above the structure of the joint structure of such curved hollow bodies As a means to do.
[0008]
The joint structure of the curved hollow body according to claim 2 of the present invention includes a pair of opposing walls provided at the front end portions of the pair of opposing walls continuously provided on the one-side hollow portion forming wall and a pair of opposing portions on the other-side hollow portion forming wall. between the portion located outside the walls, and a configuration provided with a gap to the molten resin.
[0009]
The joint structure of the curved hollow body according to claim 3 of the present invention is provided with a stepped portion continuous to the one-side hollow portion forming wall on the pair of opposing walls of one half-resin molded body, and the other The other side hollow part forming wall of the half resin molded body is provided with an engaging portion with a step portion of one half resin molded body, and the other side hollow part forming wall of the other half resin molded body is A hollow portion having a substantially circular cross section is formed together with the hollow portion forming wall on one side in a state where the engaging portion is engaged with the stepped portion of one half resin molded body between a pair of opposing walls of the half resin molded body. It is set as the structure to form.
[0010]
The joint structure of the curved hollow body according to claim 4 of the present invention is provided with a restricting means for restricting the engagement portion of the other-side hollow portion forming wall from being separated from the stepped portion of the one half resin molded body. In the joint structure of the curved hollow body according to claim 5 of the present invention, the restricting means includes a protrusion having a wedge shape in cross section located at the tip of the engaging portion of the other hollow portion forming wall, It is set as the structure which consists of the groove | channel which is located between the one side hollow part formation wall and level | step-difference part of this half resin molding, and latches with the protrusion of the other side hollow part formation wall.
[0011]
[Effects of the Invention]
Since the curved hollow body joint structure according to claim 1 of the present invention has the above-described configuration, when a half hollow resin molded body is joined to form a curved hollow body, one half A hollow portion having a substantially circular cross section is formed by the one-side hollow portion forming wall having a circular cross section of the split resin molded body and the other-side hollow portion forming wall of the other half-split resin molded body. When the curved hollow body is used as a port of the intake manifold, the cross-sectional shape of the end portion and the intermediate portion of the port does not change greatly, so that an increase in intake resistance is suppressed to a low level . At this time, the other-side hollow portion forming wall is inserted between a pair of opposing walls provided continuously to the one-side hollow portion forming wall, and the other-side hollow portion is at least partly cross-sectioned at the joint portion of the curved hollow body. Since the entire arc surface on the hollow part side of the forming wall is in a state of entering between the pair of opposing walls, the overlapping region between the pair of opposing walls and the other side hollow part forming wall that is continuous with the one side hollow part forming wall is wide. Thus, in addition to increasing the rigidity of the curved hollow body, the sealing performance when the molten resin is filled in the gap provided between the halved resin molded bodies is improved .
[0012]
In the joint structure of the curved hollow body according to the second aspect of the present invention, the rigidity of the curved hollow body is increased and the halved resin molding is performed as in the joint structure of the curved hollow body according to the first aspect. The sealing performance when the molten resin is filled in the gap provided between the bodies is improved, and in the joint structure of the curved hollow body according to claim 3 of the present invention, the injection molded halved resin molded bodies are To form a curved hollow body, the engaging portions of the other-side hollow molded body in the other half-shaped resin molded body engage with the stepped portions of one half-shaped resin molded body, respectively. The rigidity of the hollow body is further increased.
[0013]
In the joint structure of the curved hollow body according to claim 4 of the present invention, the above-described configuration is adopted, so that the engagement portion of the other-side hollow portion forming wall is warped by the contraction of the other half-split resin molded body. Since the regulating means prevents the halved resin molded body from being separated from the stepped portion, the state in which the other side hollow portion forming wall is smoothly continuous with the one side hollow portion forming wall is maintained. As a result, the rigidity is improved and the bonding strength of the joint is increased.
[0014]
In the joint structure of the curved hollow body according to claim 5 of the present invention, since it has the above-described configuration, the engaging portion of the other-side hollow part forming wall due to the contraction of the other half-split resin molded body with a simple structure. Will be prevented.
[0015]
【The invention's effect】
In the joint structure of the curved hollow body according to claim 1 of the present invention, since the above-described configuration is adopted, if the curved hollow body is formed by joining the half-molded resin molded bodies that are injection-molded, the cross-section is substantially circular. If the curved hollow body is used as a port of the intake manifold, it is possible to suppress the increase in intake resistance, and at this time, it is continuous with the hollow forming wall on one side. It is possible to increase the rigidity of the curved hollow body by the extent that the overlapping region between the pair of opposing walls and the other-side hollow portion forming wall can be widened, and to melt between the halved resin molded bodies A very excellent effect is achieved that an improvement in sealing performance against the resin can be realized .
[0016]
The junction structure of the curved hollow body according to claim 2 of the present invention, since the configuration described above, similarly to the junction structure of the curved hollow body according to claim 1, the rigidity of the bay Kyokujo hollow body It is possible to enhance the sealing performance against the molten resin between both halved resin molded bodies, and the curved hollow body joint structure according to claim 3 of the present invention has the above-described configuration. Therefore, a very excellent effect that the rigidity of the curved hollow body can be greatly increased is brought about.
[0017]
In the joint structure of the curved hollow body according to claim 4 of the present invention, since it has the above-described configuration, it is possible to maintain a smooth continuous state between the one-side hollow portion forming wall and the other-side hollow portion forming wall. Further, it is possible to realize further improvement of rigidity and reduction of noise and vibration due to this, and it is also possible to realize an increase in joint strength of the joint portion, and the curved hollow according to claim 5 of the present invention. In the body joint structure, since it has the above-described configuration, it is possible to prevent the engagement portion of the other-side hollow portion forming wall from warping due to shrinkage of the other half-split resin molded body with a simple structure. Has an excellent effect.
[0018]
【Example】
Hereinafter, the present invention will be described with reference to the drawings.
[0019]
FIG. 1 shows an embodiment of a joint structure of a curved hollow body according to the present invention. In this embodiment, the curved hollow body is a port of an intake manifold.
[0020]
As shown in FIG. 1A, the intake manifold 1 is formed using the DSI method, and a cylinder head flange 5 is provided on one end side of a U-shaped port (curved hollow body) 2. The surge tank 6 is arranged on the other end side, and the port 2 is formed by joining one half resin molded body 3 and the other half resin molded body 4 which are injection-molded. Yes.
[0021]
As shown in FIG. 1 (b), one half-shaped resin molded body 3 includes a one-side hollow portion forming wall 31 whose cross section facing the other half-shaped resin molded body 4 has an arc shape, and this one side. A pair of opposed walls 32, 32 that are continuous with the hollow portion forming wall 31 and extend to the other half-shaped resin molded body 4 side and are parallel to each other, and one hollow portion located on the pair of opposed walls 32, 32 Stepped portions 33 and 33 are provided on the forming wall 31 respectively.
[0022]
The other halved resin molded body 4 is provided with a hollow portion 21 having a substantially circular cross section along with the one-side hollow portion forming wall 31 inserted between a pair of opposing walls 32, 32 of one halved resin molded body 3. The other side hollow part forming wall 41 to be formed is provided . In this case, in the cross section of at least a part of the joint portion, the entire arc surface on the hollow portion 21 side of the other-side hollow portion forming wall 41 is inserted between the pair of opposing walls 32, 32, and the other-side hollow portion is formed. Both ends of the wall 41 shown in the figure are formed as engaging portions 43, 43 with the step portions 33, 33 of one half-resin molded body 3, and the other-side hollow portion forming wall 41 is a pair of opposing walls 32. The hollow portion 21 is formed together with the one-side hollow portion forming wall 31 in a state where the engaging portions 43, 43 are engaged with the step portions 33, 33, respectively.
[0023]
The port 2 is formed by inserting the other side hollow portion forming wall 41 of the other half-shaped resin molded body 4 between the pair of opposing walls 32, 32 of one half-shaped resin molded body 3. The four engaging portions 43, 43 are engaged with the stepped portions 33, 33 of one half-split resin molded body 3 to form a joined state, and then a pair of opposing walls 32 that are continuous with the one-side hollow portion forming wall 31. , 32 and the gap 22 formed between the tip portion of the other side hollow portion forming wall 41 and the portion located outside the pair of opposing walls 32, 32 is filled with the molten resin 7. In this state, the hollow portion 21 having a substantially circular cross section is formed inside the port 2 by the hollow portion forming walls 31 and 41.
[0024]
Therefore, in the port 2 having the above-described joint structure, the cross-sectional shape of the hollow portion 21 is maintained in a substantially circular shape from one end side where the cylinder head flange 5 is disposed to the other end side where the surge tank 6 is disposed. That is, since the cross-sectional shape of the hollow portion 21 does not change greatly, an increase in the intake resistance is suppressed to be extremely low . At this time, between the pair of opposing walls 32 and 32 that are continuous with the one-side hollow portion forming wall 31. The other side hollow portion forming wall 41 is inserted, and in the cross section of the joint portion, the entire arc surface on the hollow portion 21 side of the other side hollow portion forming wall 41 enters between the pair of opposing walls 32, 32. Therefore, the overlapping region between the pair of opposing walls 32, 32 and the other-side hollow portion forming wall 41 is widened, and the rigidity of the port 2 is increased by that much, and the halved resin molded bodies 3, 4 are while Will be improved sealability at the time of filling the molten resin into the gap 22, pressure strong point, at the junction of the port 2, the engaging portion 43 of the other side hollow section forming wall 41 in the other half resin molding 4 , 43 are respectively engaged with the step portions 33, 33 of one half-resin molded product 3, the rigidity of the port 2 is greatly increased.
[0025]
FIG. 2 shows another embodiment of the joint structure of the curved hollow body according to the present invention, and the joint structure of the curved hollow body in this embodiment is the joint section of the curved hollow body in the previous embodiment. The difference from the structure is that the engaging portion 43 of the other side hollow portion forming wall 41 in the other half resin molded body 4A constituting the port 2A is separated from the stepped portion 33 of the one half resin molded body 3A. The other means is the same as the previous embodiment.
[0026]
In this case, the regulating means includes a protrusion 44 having a wedge shape in cross section located at the tip of the engaging portion 43 of the other-side hollow portion forming wall 41, and the one-side hollow portion forming wall 31 of one half-shaped resin molded body 3A. The groove 34 is located between the step portion 33 and engages with the protrusion 44 of the other-side hollow portion forming wall 41.
[0027]
In the port 2A having the above-described joint structure, the protrusion 44 of the other-side hollow portion forming wall 41 and the groove 34 of one half-shaped resin molded body 3A are engaged with each other. Since the engagement portion 43 is warped by contraction and is prevented from separating from the stepped portion 33 of the one half resin molded body 3 </ b> A, the other-side hollow portion forming wall 41 is formed with respect to the one-side hollow portion forming wall 31. In addition to maintaining a smooth and continuous state, the rigidity is improved and the joint strength of the joint is increased.
[0028]
In the above-described embodiment, the case where the curved hollow body is the port of the intake manifold is shown, but the present invention is not limited to this.
[0029]
Moreover, the detailed structure of the junction structure of the curved hollow body according to the present invention is not limited to the above-described embodiment.
[Brief description of the drawings]
FIG. 1 is an explanatory side view of an intake manifold showing an embodiment of a curved hollow body joint structure according to the present invention, and FIG. 1 (a) is a cross-sectional explanatory view of a port at the position AA in FIG. (B).
FIG. 2 is a cross-sectional explanatory view of a port at a position corresponding to the line AA of FIG. 1A, showing another embodiment of the joint structure of the curved hollow body according to the present invention.
FIGS. 3A and 3B are an explanatory side view of an intake manifold showing a conventional joint structure of a curved hollow body, and a cross-sectional explanatory view of a port at a BB line position in FIG.
[Explanation of symbols]
2,2A port (curved hollow body)
3, 3A One half resin molded body 4, 4A The other half resin molded body 7 Molten resin 21 Hollow portion 22 Gap 31 One side hollow portion forming wall 32 Pair of opposing walls 33 Stepped portion 34 Groove (regulating means)
41 Other side hollow portion forming wall 43 Engaging portion 44 Projection (regulating means)

Claims

In the joint part of a curved hollow body formed by joining injection molded halved resin molded bodies and filling a gap between them with molten resin, one halved resin molded body has the other The one side hollow part forming wall having an arc-shaped cross section facing the half resin molded body side is provided, and the other half resin molded body has a hollow part having a substantially circular cross section together with the one side hollow part forming wall. The other hollow portion forming wall to be formed is provided , and a pair of opposing walls extending to the other half-shaped resin molded body side in parallel with the one side hollow portion forming wall and parallel to each other are provided, and between the pair of opposing walls. A hollow portion having a substantially circular cross section is formed together with the one side hollow portion forming wall by inserting the other side hollow portion forming wall, and the other side hollow portion is formed in a cross section of at least a part of the joint portion of the curved hollow body. The entire arc surface on the hollow side of the wall is inserted between the pair of opposing walls. Junction structure of curved hollow bodies, wherein the certain this.

A molten resin is filled between each tip portion of the pair of opposing walls provided continuously to the one-side hollow portion forming wall and a portion located outside the pair of opposing walls in the other-side hollow portion forming wall. junction structure of curved hollow member according to 請 Motomeko 1 provided with the gap.

A pair of opposing walls of one half-resin molded body is provided with a stepped portion that is continuous with the one-side hollow portion forming wall, and one half-split is formed on the other-side hollow portion-forming wall of the other half-shaped resin molded body. An engagement portion with a stepped portion of the resin molded body is provided, and the other hollow portion forming wall of the other half-split resin molded body has one engagement portion between a pair of opposing walls of one half-split resin molded body. The joint structure of a curved hollow body according to claim 1 or 2 , wherein a hollow part having a substantially circular cross section is formed together with the one-side hollow part forming wall in a state of being engaged with the stepped parts of the half-resin molded body. .

The joint structure of the curved hollow body according to claim 3, further comprising a restricting means for restricting the engaging portion of the other-side hollow portion forming wall from being separated from the stepped portion of the one half resin molded body.

The restricting means is located between the protrusion having a wedge shape in cross section located at the tip of the engaging portion of the other-side hollow portion forming wall and the one-side hollow portion forming wall and the step portion of one half-resin molded body. The joint structure of the curved hollow body according to claim 4, comprising a protrusion on the other hollow portion forming wall and a groove for locking.