JP4596640B2

JP4596640B2 - Variable orifice device

Info

Publication number: JP4596640B2
Application number: JP2000398801A
Authority: JP
Inventors: 和彦渡辺; 昌賢箕輪
Original assignee: Fujikoki Corp
Current assignee: Fujikoki Corp
Priority date: 2000-10-05
Filing date: 2000-12-27
Publication date: 2010-12-08
Anticipated expiration: 2020-12-27
Also published as: JP2002181227A

Description

【０００１】
【発明の属する技術分野】
本発明は、流路を流れる流体の温度に応じて絞り量（弁開度）を自動的に調節できるようされた可変オリフィス装置に関する。
【０００２】
【従来の技術】
例えば、カーエアコンに用いられる冷凍サイクル等においては、その流路を流れる流体（冷媒）の流量を、その流体の温度に応じて変化させること、例えば、起動時に低圧側の冷媒温度が高い場合にはその流量を増加させ、起動後、冷媒温度が下がるに従いその流量を減少させること、が望まれる場合がある。
【０００３】
【発明が解決しようとする課題】
前記のように、流路を流れる流体の流量を、その流体の温度に応じて変化させるべく、流路に可変オリフィス装置を設けることは、従来より考えられているが、従来の可変オリフィス装置は、組み立て性、流路（導管）への組み込み性等がさほど考慮されておらず、構造が複雑で部品点数が多く、製造コストが高くなる嫌いがあった。
【０００４】
本発明は、上記のような課題に鑑みてなされたもので、その目的とするところは、流路を流れる流体の流量を、その流体の温度に応じて可変調整とすることができ、かつ、組み立て性、流路（導管）への組み込み性等に優れ、構造の簡素化、部品点数の削減、製造コストの低減を図ることができるようにされた可変オリフィス装置を提供することにある。
【０００５】
【課題を解決するための手段】
前記の目的を達成すべく、本発明に係る可変オリフィス装置は、流体が流れる流路に組み込まれ、線膨張係数の異なる異種材料からなるオリフィスケースと弁体とを備え、前記オリフィスケースの一端側に絞り通路が形成され、前記オリフィスケース内に前記弁体が伸縮自在に挿入されるとともに、該弁体の基端部が前記オリフィスケースの他端側に固定され、流体の温度変化に応じて生じる前記オリフィスケースと前記弁体との伸縮量の差により、流路を流れる流体は前記弁体で前記絞り通路を流れる流量を可変調整するものであり、前記オリフィスケースは、その外周に前記流路を封止するためのＯリングが装着される大径部が一端側に形成され、該大径部から流路に沿って伸びる、前記流路に内接する矩形断面外形の筒状ケース部が他端側に形成されていることを特徴としている。
【０００６】
この場合、好ましい態様では、前記オリフィスケース及び前記弁体のうちの一方が金属製で、他方が樹脂製とされる。
【０００７】
また、前記弁体は、好ましくは、その基端部に前記オリフィスケースの他端部に形成された雌ねじ部に螺合せしめられる雄ねじ部が形成され、その先端部に前記絞り通路に対向配置される絞り用円錐状部が形成された棒状体からなる。
他の好ましい態様では、前記弁体は、その基端部に前記オリフィスケースの他端部に形成された雌ねじ部に螺合せしめられる雄ねじ部が形成された棒状体と、該棒状体の先端部に連結されて前記絞り通路に挿通せしめられ、その外端側に絞り用円錐状部が形成されたピン状体とからなる。
【０００８】
このような構成とされた本発明に係る可変オリフィス装置の好ましい態様においては、それを組み立てるにあたっては、オリフィスケースの筒状ケース部内に棒状体からなる弁体を挿入し、その基端部に形成された雄ねじ部を前記筒状ケース部の他端部に形成された雌ねじ部に螺合させて位置決め固定する。この状態では、弁体の先端（絞り用円錐状部の先端）がオリフィスケースの大径部に形成されている絞り通路から所定の距離だけ離隔せしめられた位置に対向配置される。
【０００９】
この可変オリフィス装置を流路（導管）に組み込むにあたっては、前記オリフィスケースの大径部の外周にＯリングを装着して、導管内に押し込むだけでよく、これにより、前記大径部と導管内周面との間が前記Ｏリングにより封止され、かつ、好ましい態様では、矩形断面外形を有する前記筒状ケース部の四つのコーナー部が前記導管内周面に内接するとともに、該筒状ケース部の外周四面と導管内周面との間に四つの流路が形成される。
【００１０】
この場合、前記弁体の先端と絞り通路との離隔距離が弁開度とされ、この弁開度が大きいほど、前記絞り通路を流れる流体の流量が増加する。そして、前記弁開度は、線膨張係数の異なる異種材料からなる前記オリフィスケースと前記弁体との、流体の温度変化に応じて生じる伸縮量の差により変化する。
【００１１】
ここで、例えば、前記弁体が金属製で、前記オリフィスケースが樹脂製とされ、冷凍サイクルを構成する導管内を流体（高圧の冷媒）が可変オリフィス装置の一端側（大径部側）から他端側に向けて流されると仮定すると、冷媒は、絞り通路から、該絞り通路と弁体の先端との間に形成される隙間（前記弁開度に相当する）を通り、さらに、該筒状ケース部に形成された通し穴からその外周四面と導管内周面との間に形成された流路に流出して導管下流側へと流れる。
【００１２】
前記絞り通路を出た冷媒は、膨張して降温されるので、可変オリフィス装置を流れる冷媒の温度は次第に下がり、この冷媒温度の低下により、前記弁体及び前記オリフィスケース（の筒状ケース部）は縮むが、その縮み量は、金属製の弁体に比して樹脂製のオリフィスケースの方がかなり大きく（線膨張係数は５〜１０倍）、その縮み量の差だけ、前記弁体の先端と絞り通路との離隔距離とされる弁開度が小さくなり、これによって、前記絞り通路を流れる冷媒流量が減じられる。
このように、本発明の可変オリフィス装置においては、流路を流れる流体の流量を、その流体の温度に応じて可変とすることができる。
【００１３】
また、本発明の可変オリフィス装置は、基本的には、オリフィスケースと弁体の２部品で構成されるので、構造の簡素化、部品点数の削減が図られ、さらに、オリフィスケースに弁体を螺合させること等により簡単に組み立てることができる上、Ｏリングを装着する等して流路（導管）に押し込むだけで組み付けることができるので、組み立て性、流路（導管）への組み込み性等に優れたものとなり、製造コスト、組立及び組込コストの低減を図れる。
【００１４】
前記に加えて、本発明の可変オリフィス装置の好ましい態様では、前記オリフィスケース内の前記弁体の先端若しくは前記弁体の先端と対面する位置に、閉弁機能を有した弁が配設される。
前記閉弁機能を有した弁としては、例えば、前記オリフィスケースの大径部内に配在されて、前記絞り通路あるいはそれと前記弁体との間に形成される隙間等を開閉する閉弁用弁体と、該閉弁用弁体を通常の流れ方向とは逆方向、つまり、前記絞り通路等を閉じる方向に付勢するコイルばね等の付勢手段とで構成したものが挙げられる。
【００１５】
このように、閉弁機能を有した弁を配設した可変オリフィス装置では、例えば、冷凍サイクルの作動時には、当該可変オリフィス装置の上流側（コンプレッサ側）の方が下流側（エバポレータ側）より流体（冷媒）との圧力差が高いので、前記閉弁機能を有した弁は、その閉弁用弁体が前記コイルばね等の付勢手段の付勢力に抗して押し下げられ、前記絞り通路あるいはそれと前記弁体との間に形成される隙間等を開く開状態となる。
【００１６】
それに対し、冷媒サイクルの作動を停止すると、当該可変オリフィス装置の上流側の圧力は急速に低下し、下流側との圧力差が小さくなる。このときには、前記閉弁機能を有した弁は、その閉弁用弁体が前記コイルバネ等の付勢手段の付勢力により通常の流れ方向とは逆方向に押圧移動せしめられ、前記絞り通路あるいはそれと前記閉弁用弁体との間に形成される隙間等を閉じる閉状態となる。
【００１７】
このように、本発明の可変オリフィス装置に閉弁機能を有した弁を配設することで、冷凍サイクルの作動を停止状態で流体が当該可変オリフィス装置を介して上流側から下流側へ流れることを防止でき、エバポレータへの冷媒液の流入を防ぐことができる。冷凍サイクルにおいて、このエバポレータへの液冷媒の流入を防ぐことにより、再起動時でのコンプレッサへの液流入を押さえることができ、コンプレッサへのトルク負荷を低減できる。
【００１８】
【発明の実施の形態】
以下、本発明の実施形態を図面を参照しながら説明する。
図１は、本発明に係る第１実施形態の可変オリフィス装置を導管に組み込んだ状態を示す部分切欠斜視図、図２は、その部分切欠断面図、図３は、その主要部の拡大断面図である。
【００１９】
図示の第１実施形態の可変オリフィス装置１は、図２（Ａ）において、左側（ＩＮ側）から右側（ＯＵＴ側）へと冷媒が流される、冷凍サイクルを構成する導管５に組み込まれるようにされており、線膨張係数の異なる異種材料からなるオリフィスケース１０と弁体２０とを備える。ここでは、オリフィスケース１０は樹脂（例えばポリアセタール）製とされ、弁体２０は金属（例えばＳＵＳ３０３）製とされている。
【００２０】
前記オリフィスケース１０は、一端側（図２（Ａ）の左端側）に設けられた大径部１２と、該大径部１２から冷媒流路を形成する導管５に沿って伸びる、前記導管５に内接する（図２（Ｂ）参照）矩形断面外形の筒状ケース部１１と、からなっている。前記大径部１２の中央には、絞り通路１４が貫通せしめられ、その外周には、流路を封止するためのＯリング１８が装着されるリング溝１３が形成されている。前記筒状ケース部１１の一端部（大径部１２側）の四面にはそれぞれ通し穴１６が形成されている。
【００２１】
前記弁体２０は、前記筒状ケース部１１に遊挿され、その基端部（図２（Ａ）の右端部）に前記オリフィスケース１０の筒状ケース部１１の他端部に形成された雌ねじ部１７に螺合せしめられる雄ねじ部２４が形成された円柱部２１と、該円柱部２１から前記大径部１２側に突出せしめられた小径先端部２２と、からなる段付きの棒状体とされ、前記小径先端部２２の先端は、前記絞り通路１４に対向配置される絞り用円錐状部が形成されている。
【００２２】
このような構成とされた本発明第１実施形態の可変オリフィス装置１においては、それを組み立てるにあたっては、オリフィスケース１０の筒状ケース部１１内に棒状体からなる弁体２０を挿入し、その基端部に形成された雄ねじ部２４を前記筒状ケース部１１の他端部に形成された雌ねじ部１７に螺合させて位置決め固定する。この状態では、図３に示される如くに、弁体２０の先端（小径先端部２２における絞り用円錐状部の先端）がオリフィスケース１０の大径部１２に形成されている絞り通路１４（大径部１２の右端）から所定の距離（ΔＬ）だけ離隔せしめられた位置に対向配置される。
【００２３】
この可変オリフィス装置１を流路を形成する導管５に組み込むにあたっては、前記オリフィスケース１０の大径部１２の外周にＯリング１８を装着して、導管５内に押し込むだけでよく、これにより、前記大径部１２と導管５の内周面との間が前記Ｏリング１８により封止され、かつ、図２（Ｂ）に示される如くに、矩形断面外形を有する前記筒状ケース部１１の四つのコーナー部が前記導管５の内周面に内接するとともに、該筒状ケース部１１の外周四面と導管５の内周面との間に四つの流路が形成される。
【００２４】
この場合、前記弁体２０の先端と絞り通路１４（大径部１２の左端）との離隔距離、言い換えれば、図３に示される如くに、そのときの前記筒状ケース部１１の長さＬｂから前記弁体１０の長さＬａを減じた値が弁開度ΔＬとされ、この弁開度ΔＬが大きいほど、前記絞り通路１４を流れる冷媒の流量が増加する。そして、前記弁開度ΔＬは、樹脂製のオリフィスケース１０と金属製の弁体２０との、冷媒の温度変化に応じて生じる伸縮量の差により変化する。
【００２５】
ここでは、樹脂（ＰＯＭ）製のオリフィスケース１０の、２０°Ｃにおける線膨張係数は１０２×１０-6／℃であり、金属（ＳＵＳ３０３）製の弁体２０の線膨張係数は１４．７×１０-6／℃とされ、冷凍回路を構成する導管５内を高圧の冷媒が可変オリフィス装置１の一端側（ＩＮ側）から他端側（ＯＵＴ側）に向けて流される。
【００２６】
このため、冷媒は、絞り通路１４から、該絞り通路１４と弁体２０の先端との間に形成される隙間（前記弁開度ΔＬに相当する）を通り、さらに、該筒状ケース部１１に形成された四つの通し穴１６からその外周四面と導管５の内周面との間に形成された流路に流出して導管５の下流側へと流れる。
【００２７】
前記絞り通路１４を出た冷媒は、膨張して降温されるので、可変オリフィス装置１を流れる冷媒の温度は次第に下がり、この冷媒温度の低下により、前記弁体２０及び前記オリフィスケース１０（の筒状ケース部１１）は縮むが、その縮み量は、前記線膨張係数に応じたものとなり、その縮み量の差だけ、前記弁体２０の先端と絞り通路１４との離隔距離とされる弁開度ΔＬが小さくなる（図４の弁開度−温度特性を表すグラフを参照）、これによって、前記絞り通路１４を流れる冷媒流量が減じられる。
このように、本発明第１実施形態の可変オリフィス装置１においては、流路を流れる流体の流量を、その流体の温度に応じて可変とすることができる。
【００２８】
また、本実施形態の可変オリフィス装置１は、基本的には、オリフィスケース１０と弁体２０の２部品で構成されたので、構造の簡素化、部品点数の削減が図られ、さらに、オリフィスケース１０に弁体２０を螺合させることにより簡単に組み立てることができる上、Ｏリング１８を装着する等して流路（導管５）に押し込むだけで組み付けることができるので、組み立て性、流路（導管）への組み込み性等に優れたものとなり、製造コスト、組立及び組込コストの低減を図れる。
【００２９】
図５は本発明に係る第２実施形態の可変オリフィス装置２を導管に組み込んだ状態を示す部分切欠断面図、図６は、その主要部の拡大断面図を示している。
図示実施形態の可変オリフィス装置２は、第１実施形態と同様に、図５において、左側（ＩＮ側）から右側（ＯＵＴ側）へと冷媒が流される、冷凍サイクルを構成する導管５に組み込まれるようにされており、第１実施形態のものと材質は異なるが同一形状の金属（ＳＵＳ３０３）製のオリフィスケース１０’と、第１実施形態のものと材質が異なり、かつ、形状構成も若干異なる樹脂（ＰＯＭ）製の弁体３０と、を備える。
【００３０】
前記弁体３０は、その基端部に前記オリフィスケース１０’の他端部に形成された雌ねじ部１７に螺合せしめられる雄ねじ部３４が形成され、前記オリフィスケース１０’の筒状ケース部１１’に伸縮自在に遊挿された円柱状の棒状体３１と、該棒状体３１の先端部に連結されたピン状体３５と、からなり、該ピン状体３５は、前記棒状体３１の先端部にねじ込まれて（圧入等でも可）連結された雄ねじ部３８と、前記絞り通路１４に挿通せしめられた挿通部３７と、該挿通部の外端側（ＩＮ側）に設けられた絞り用円錐状部３６と、からなっている。
【００３１】
このような構成とされた第２実施形態の可変オリフィス装置２においては、金属製のオリフィスケース１０’より樹脂製の弁体３０の方が線膨張係数が大きくなるので、冷媒の温度が低下すると、前記絞り用円錐状部３６と前記絞り通路１４との離隔距離とされる弁開度が小さくなり、これによって、前記絞り通路１４を流れる冷媒流量が減じられ、前記第１実施形態の可変オリフィス装置１と略同様な作用効果が得られる。
【００３２】
図７は本発明に係る第３実施形態の可変オリフィス装置３を導管に組み込んだ状態を示す部分切欠断面図、図８は本発明に係る第４実施形態の可変オリフィス装置４を導管に組み込んだ状態を示す部分切欠断面図である。
図７、図８に示される第３及び第４の可変オリフィス装置３、４は、第１及び第２実施形態とは逆に、図７、図８において、右側（ＩＮ側）から左側（ＯＵＴ側）へと冷媒が流される、冷凍サイクルを構成する導管５に組み込まれるようにされており、第３実施形態の可変オリフィス装置３は、第１実施形態のものと材質は異なるが同一形状の金属（ＳＵＳ３０３）製のオリフィスケース１０’と樹脂（ＰＯＭ）製の弁体２０’と、を備える。また、第４実施形態の可変オリフィス装置４は、第２実施形態のものと材質は異なるが同一形状の樹脂（ＰＯＭ）製のオリフィスケース１０と金属（ＳＵＳ３０３）製の弁体３０’と、を備える。
【００３３】
かかる構成の第３及び第４実施形態の可変オリフィス装置３、４においては、温度変化に応じて縮み作用を生じる弁体が絞り通路の前段（冷媒のＩＮ側に近い位置）に配置されているので、弁体は冷媒温度を感知し、高圧側の冷媒温度は冷凍サイクルの起動時は低く、起動後は上昇することから、第１実施形態及び第２実施形態とはオリフィスケースと弁体との組合せを逆の組合せとすることによって、その起動時の冷媒温度が低い場合に弁開度は大きくなり、その起動後は温度が上昇して弁開度は小さくなる。したがって、第１及び第２実施形態の可変オリフィス装置１、２と同様な作用効果が得られる。
【００３４】
図９に示される第５実施形態の可変オリフィス装置１Ａは、図１〜図３に示される第１実施形態の可変オリフィス装置１と基本構成が同じものに、閉弁機能を有した弁５０を付設したものである。
すなわち、図示実施形態の可変オリフィス装置１Ａは、図９（Ａ）において、左側（ＩＮ側）から右側（ＯＵＴ側）へと冷媒が流される、冷凍サイクルを構成する導管５に組み込まれるようにされており、第１実施形態と同様に樹脂製のオリフィスケース１０と金属製の弁体２０とを備え、該弁体２０の先端に、冷媒の逆流を防止する閉弁機能を有した弁５０が配設されている。
【００３５】
この閉弁機能を有した弁５０は、前記絞り通路１４を開閉する、前記弁体２０の先端部２２の絞り用円錐状部を兼用する円錐状の閉弁用弁体５１と、該閉弁用弁体５１を通常の流れ方向（ＩＮ→ＯＵＴ）とは逆方向、つまり、絞り通路１４を閉じる方向に付勢する付勢手段としてのコイルばね５２とを備える。
ここでは、前記閉弁用弁体５１の後面と前記弁体２０の先端部２２との間に前記コイルばね５２が縮装されるとともに、前記閉弁用弁体５１の後面側中央には、前記弁体２０の先端部中央に穿設された案内穴５６に摺動自在に嵌挿される案内ロッド５５が突設され、かつ、前記閉弁用弁体５１の後面及び前記弁体２０の先端部２２には、前記コイルばね５２を伸縮自在に案内する案内筒部５４、５６が突設されている。
【００３６】
かかる閉弁機能を有した弁５０を配設した可変オリフィス装置１Ａでは、例えば、冷凍サイクルの作動時には、当該可変オリフィス装置１Ａの上流側（ＩＮ側＝コンプレッサ側）の冷媒の圧力Ｐｉと下流側（ＯＵＴ側＝エバポレータ側）の冷媒の圧力Ｐｏとの圧力差が高いので、前記閉弁機能を有した弁５０は、図９（Ａ）に示される如くに、その閉弁用弁体５１が前記コイルばね５２の付勢力に抗して、前記案内筒部５３、５４同志が接当する位置まで押し下げられ、該閉弁用弁体５１と前記絞り通路１４の右端（前記大径部１２の右端）とは、第１実施形態の可変オリフィス装置１における弁体２０の絞り用円錐状部と前記絞り通路１４の右端（前記大径部１２の右端）との離隔距離（ΔＬ）と同じ距離だけ離間せしめられ、前記絞り通路１４は開状態となる。
【００３７】
したがって、冷凍サイクルの作動時には、第１実施形態と同様に、前記絞り通路１４を出た冷媒は、膨張して降温されるので、可変オリフィス装置１Ａを流れる冷媒の温度は次第に下がり、この冷媒温度の低下により、前記閉弁用弁体５１を含む弁体２０及び前記オリフィスケース１０（の筒状ケース部１１）は縮むが、その縮み量は、前記線膨張係数に応じたものとなり、その縮み量の差だけ、前記弁体２０の先端と絞り通路１４との離隔距離とされる弁開度ΔＬが小さくなり、これによって、前記絞り通路１４を流れる冷媒流量が減じられ、その結果、流路を流れる冷媒流量が、その温度に応じて調節される。
【００３８】
それに対し、冷凍サイクルを停止すると、当該可変オリフィス装置１Ａの上流側の圧力Ｐｉは急速に低下し、下流側の圧力Ｐｏとの圧力差が小さくなる。このときには、前記閉弁機能を有した弁５０は、図９（Ｂ）に示される如くに、その閉弁用弁体５１が前記コイルばね５２の付勢力により、通常の流れ方向とは逆方向に押圧移動せしめられ、前記絞り通路１４を閉じる閉状態となる。
このように、閉弁機能を有した弁５０を配設したことで、冷媒が当該可変オリフィス装置１Ａを介して上流側から下流側へ流れることを防止でき、エバポレータへの冷媒液の流入を防ぐことが出来る。冷凍サイクルにおいて、このエバポレータへの冷媒液の流入を防ぐことにより、再起動時でのコンプレッサへの液流入を押さえることができ、コンプレッサへのトルク負荷を低減出来る。
【００３９】
図１０に示される第６実施形態の可変オリフィス装置１Ａは、図７に示される第３実施形態の可変オリフィス装置３と基本構成が同じものに、閉弁機能を有した弁６０を付設したものである。
すなわち、図示実施形態の可変オリフィス装置３Ａは、図１０（Ａ）において、右側（ＩＮ側）から左側（ＯＵＴ側）へと冷媒が流される、冷凍サイクルを構成する導管５に組み込まれるようにされており、第３実施形態と同様に金属製のオリフィスケース１０’と樹脂製の弁体２０’とを備え、該オリフィスケース１０’内の弁体２０’の先端と対面する位置に、冷媒の逆流を防止する閉弁機能を有した弁６０が配設されている。
【００４０】
この閉弁機能を有した弁６０は、筒状ケース部１１’における前記オリフィスケース１０’の大径部１２’内に間に摺動自在に嵌挿されて前記絞り通路１４と前記弁体２０’の絞り用円錐状部２２ａとの間に形成される隙間を開閉する、ばね受け兼受圧用の鍔状内縁部６１ａを有する円筒状の閉弁用オリフィス６１と、該閉弁用オリフィス６１とオリフィスケース１０’との間のシール材としてのＯリング６１ｂと、該閉弁用オリフィス６１を通常の流れ方向（ＩＮ→ＯＵＴ）とは逆方向、つまり、絞り通路１４と前記弁体２０’の絞り用円錐状部２２ａとの間に形成される隙間を閉じる方向に付勢する付勢手段としてのコイルばね６２とを備える。
【００４１】
ここでは、前記コイルばね６２は、前記円筒状の閉弁用オリフィス６１内に装填されて、前記大径部１２の右端と前記閉弁用オリフィス６１の鍔状内縁部６１ａとの間に縮装されている。
かかる閉弁機能を有した弁５０を配設した可変オリフィス装置３Ａにおいても、第５実施形態と同様に、例えば、冷凍サイクルの作動時には、当該可変オリフィス装置３Ａの上流側（ＩＮ側＝コンプレッサ側）の冷媒の圧力Ｐｉと下流側（ＯＵＴ側＝エバポレータ側）の冷媒の圧力Ｐｏとの圧力差が高いので、前記閉弁機能を有した弁６０は、図１０（Ａ）に示される如くに、その閉弁用オリフィス６１が前記コイルばね６２の付勢力に抗して、その後端が前記大径部１２の左端に接当する位置まで押し下げられ、その鍔状内縁部６１ａが前記弁体２０の絞り用円錐状部２２ａから離間して、前記絞り通路１４と前記弁体２０’の絞り用円錐状部２２ａとの間に形成される隙間を開いた状態となる。
【００４２】
したがって、冷凍サイクルの作動時には、第３実施形態と同様に、前記絞り通路１４を出た冷媒は、膨張して降温されるので、可変オリフィス装置３Ａを流れる冷媒の温度は次第に下がり、この冷媒温度の低下により、前記弁体２０及び前記オリフィスケース１０（の筒状ケース部１１）は縮むが、その縮み量は、前記線膨張係数に応じたものとなり、その縮み量の差だけ、前記弁体２０の先端と絞り通路１４との離隔距離とされる弁開度ΔＬが小さくなり、これによって、前記絞り通路１４を流れる冷媒流量が減じられ、その結果、流路を流れる冷媒流量が、その温度に応じて調節される。
【００４３】
それに対し、冷凍サイクルの作動を停止すると、当該可変オリフィス装置３Ａの上流側の圧力Ｐｉが急速に低下し、下流側の圧力Ｐｏとの差圧が小さくなる。このときには、前記閉弁機能を有した弁６０は、図１０（Ｂ）に示される如くに、その閉弁用オリフィス６１が前記コイルばね６２の付勢力により、通常の流れ方向とは逆方向に押圧移動せしめられ、その鍔状内縁部６１ａが前記弁体２０の絞り用円錐状部２２ａに接当して、前記絞り通路１４と前記弁体２０’の絞り用円錐状部２２ａとの間に形成される隙間を閉じた状態となる。
【００４４】
このように、閉弁機能を有した弁６０を配設したことで、第５実施形態と同様に、冷媒が当該可変オリフィス装置３Ａを介して上流側から下流側へ流れることを防止でき、エバポレータへの冷媒液の流入を防ぐことが出来る。冷凍サイクルにおいて、このエバポレータへの流入を防ぐことにより、再作動時でのコンプレッサへの液流入を押さえることができ、コンプレッサへのトルク負荷を低減できる。
【００４５】
【発明の効果】
以上の説明から理解されるように、本発明によれば、流路を流れる流体の流量を、その流体の温度に応じて可変とすることができ、かつ、組み立て性、流路（導管）への組み込み性等に優れ、構造の簡素化、部品点数の削減、製造コストの低減を図ることができるようにされた可変オリフィス装置を提供できる。
【図面の簡単な説明】
【図１】本発明に係る第１実施形態の可変オリフィス装置を導管に組み込んだ状態を示す部分切欠斜視図。
【図２】（Ａ）は第１実施形態の可変オリフィス装置の部分切欠断面図、（Ｂ）は（Ａ）のＢ−Ｂ矢視断面図。
【図３】第１実施形態の可変オリフィス装置の主要部の拡大断面図。
【図４】弁開度−温度特性を表すグラフ。
【図５】本発明に係る第２実施形態の可変オリフィス装置を導管に組み込んだ状態を示す部分切欠断面図。
【図６】第２実施形態の可変オリフィス装置の主要部の拡大断面図。
【図７】本発明に係る第３実施形態の可変オリフィス装置を導管に組み込んだ状態を示す部分切欠断面図。
【図８】本発明に係る第４実施形態の可変オリフィス装置を導管に組み込んだ状態を示す部分切欠断面図。
【図９】本発明に係る第５実施形態の可変オリフィス装置を導管に組み込んだ状態を示す主要部拡大断面図。
【図１０】本発明に係る第６実施形態の可変オリフィス装置を導管に組み込んだ状態を示す主要部拡大断面図。
【符号の説明】
１〜４可変オリフィス装置
５導管
１０、１０’ オリフィスケース
１１、１１’ 筒状ケース部
１２、１２’ 大径部
１４絞り通路
２０、２０’ 弁体
３０、３０’ 弁体
５０、６０閉弁機能を有した弁
ΔＬ弁開度[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a variable orifice device capable of automatically adjusting a throttle amount (valve opening) in accordance with the temperature of a fluid flowing in a flow path.
[0002]
[Prior art]
For example, in a refrigeration cycle or the like used in a car air conditioner, the flow rate of a fluid (refrigerant) flowing through the flow path is changed in accordance with the temperature of the fluid. In some cases, it may be desirable to increase the flow rate and to decrease the flow rate as the refrigerant temperature decreases after startup.
[0003]
[Problems to be solved by the invention]
As described above, in order to change the flow rate of the fluid flowing in the flow path according to the temperature of the fluid, it has been conventionally considered to provide a variable orifice apparatus in the flow path. However, the assemblability, the incorporation into the flow path (conduit), etc. are not so much considered, and the structure is complicated, the number of parts is large, and the manufacturing cost is high.
[0004]
  The present invention provides the aboveofIn view of such a problem, the object is to make it possible to variably adjust the flow rate of the fluid flowing through the flow path according to the temperature of the fluid, It is an object of the present invention to provide a variable orifice device that is excellent in assembling into a conduit) and that can simplify the structure, reduce the number of parts, and reduce the manufacturing cost.
[0005]
[Means for Solving the Problems]
  In order to achieve the above object, a variable orifice device according to the present invention comprises:Built into the flow path through which the fluid flows,An orifice case and a valve body made of different materials having different linear expansion coefficients are provided, a throttle passage is formed on one end side of the orifice case, the valve body is inserted into the orifice case in a telescopic manner, and the valve The base end portion of the body is fixed to the other end side of the orifice case, and due to the difference in expansion and contraction between the orifice case and the valve body that occurs according to the temperature change of the fluid,The fluid flowing through the flow pathThe valve body flows through the throttle passageFlowAmountvariableAdjustmentThe orifice case has a large-diameter portion on one end side where an O-ring for sealing the flow path is attached to the outer periphery, and extends along the flow path from the large-diameter portion. A cylindrical case portion having a rectangular cross-sectional outline inscribed in the flow path is formed on the other end side..
[0006]
  In this case, in a preferred embodiment, one of the orifice case and the valve body is made of metal, and the other is made of resin.Is done.
[0007]
Further, the valve body is preferably formed with a male screw portion screwed into a female screw portion formed at the other end portion of the orifice case at a base end portion thereof, and disposed at a distal end portion thereof so as to face the throttle passage. It consists of a rod-like body in which a conical portion for drawing is formed.
In another preferred embodiment, the valve body includes a rod-like body having a male screw portion screwed to a female screw portion formed at the other end portion of the orifice case at a base end portion thereof, and a distal end portion of the rod-like body. And a pin-like body having a conical portion for constriction formed on the outer end thereof.
[0008]
In a preferred embodiment of the variable orifice device according to the present invention configured as described above, when assembling the variable orifice device, a valve body made of a rod-shaped body is inserted into the cylindrical case portion of the orifice case and formed at the base end portion thereof. The male screw portion thus formed is screwed into a female screw portion formed at the other end portion of the cylindrical case portion, and is positioned and fixed. In this state, the front end of the valve body (the front end of the conical portion for throttle) is disposed opposite to a position separated from the throttle passage formed in the large diameter portion of the orifice case by a predetermined distance.
[0009]
In order to incorporate this variable orifice device into the flow path (conduit), it is only necessary to attach an O-ring to the outer periphery of the large-diameter portion of the orifice case and push it into the conduit. Between the peripheral surface is sealed by the O-ring, and in a preferred aspect, the four corner portions of the cylindrical case portion having a rectangular cross-sectional outer shape are inscribed in the inner peripheral surface of the conduit, and the cylindrical case Four flow paths are formed between the outer peripheral four surfaces of the section and the inner peripheral surface of the conduit.
[0010]
In this case, the distance between the tip of the valve body and the throttle passage is the valve opening, and the larger the valve opening, the higher the flow rate of the fluid flowing through the throttle passage. The valve opening changes due to a difference in expansion and contraction caused by a change in temperature of the fluid between the orifice case made of different materials having different linear expansion coefficients and the valve body.
[0011]
Here, for example, the valve body is made of metal, the orifice case is made of resin, and the fluid (high-pressure refrigerant) flows from the one end side (large-diameter portion side) of the variable orifice device in the conduit constituting the refrigeration cycle. Assuming that the refrigerant flows toward the other end side, the refrigerant passes from the throttle passage through a gap formed between the throttle passage and the tip of the valve body (corresponding to the valve opening), and It flows out from the through-hole formed in the cylindrical case part to the flow path formed between the outer peripheral four surfaces and the conduit inner peripheral surface, and flows to the conduit downstream side.
[0012]
Since the refrigerant exiting the throttle passage expands and falls, the temperature of the refrigerant flowing through the variable orifice device gradually decreases. Due to the decrease in the refrigerant temperature, the valve body and the orifice case (the cylindrical case portion) However, the amount of shrinkage is considerably larger in the resin orifice case than in the metal valve body (linear expansion coefficient is 5 to 10 times), and the difference in the amount of shrinkage is that of the valve body. The opening degree of the valve, which is the separation distance between the tip and the throttle passage, is reduced, thereby reducing the flow rate of the refrigerant flowing through the throttle passage.
Thus, in the variable orifice device of the present invention, the flow rate of the fluid flowing through the flow path can be made variable according to the temperature of the fluid.
[0013]
The variable orifice device of the present invention is basically composed of two parts, an orifice case and a valve body, so that the structure can be simplified and the number of parts can be reduced. It can be assembled easily by screwing, etc., and can be assembled simply by pushing it into the flow path (conduit) by attaching an O-ring, etc. Therefore, it is possible to reduce manufacturing costs, assembly costs, and assembly costs.
[0014]
In addition to the above, in a preferable aspect of the variable orifice device of the present invention, a valve having a valve closing function is disposed at a position facing the tip of the valve body or the tip of the valve body in the orifice case. .
As the valve having the valve closing function, for example, a valve for valve closing that is arranged in a large diameter portion of the orifice case and opens and closes the throttle passage or a gap formed between the throttle passage and the valve body. And a biasing means such as a coil spring that biases the valve closing valve body in a direction opposite to the normal flow direction, that is, in a direction to close the throttle passage and the like.
[0015]
Thus, in a variable orifice device provided with a valve having a valve closing function, for example, when the refrigeration cycle is operated, the upstream side (compressor side) of the variable orifice device is more fluid than the downstream side (evaporator side). Since the pressure difference from the (refrigerant) is high, in the valve having the valve closing function, the valve closing valve body is pushed down against the urging force of the urging means such as the coil spring, and the throttle passage or It will be in the open state which opens the clearance gap formed between it and the said valve body.
[0016]
On the other hand, when the operation of the refrigerant cycle is stopped, the pressure on the upstream side of the variable orifice device rapidly decreases, and the pressure difference with the downstream side becomes small. At this time, the valve having the valve closing function is such that the valve closing valve body is pushed and moved in the direction opposite to the normal flow direction by the urging force of the urging means such as the coil spring. It will be in the closed state which closes the clearance gap etc. which are formed between the said valve bodies for valve closing.
[0017]
As described above, by disposing the valve having the valve closing function in the variable orifice device of the present invention, the fluid flows from the upstream side to the downstream side through the variable orifice device while the operation of the refrigeration cycle is stopped. It is possible to prevent the refrigerant liquid from flowing into the evaporator. In the refrigeration cycle, by preventing the liquid refrigerant from flowing into the evaporator, the liquid flow into the compressor at the time of restarting can be suppressed, and the torque load on the compressor can be reduced.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a partially cutaway perspective view showing a state in which the variable orifice device according to the first embodiment of the present invention is incorporated in a conduit, FIG. 2 is a partially cutaway sectional view thereof, and FIG. 3 is an enlarged sectional view of a main portion thereof. It is.
[0019]
The variable orifice device 1 of the illustrated first embodiment is incorporated in a conduit 5 constituting a refrigeration cycle in which refrigerant flows from the left side (IN side) to the right side (OUT side) in FIG. It includes an orifice case 10 and a valve body 20 made of different materials having different linear expansion coefficients. Here, the orifice case 10 is made of resin (for example, polyacetal), and the valve body 20 is made of metal (for example, SUS303).
[0020]
The orifice case 10 extends along a large diameter portion 12 provided on one end side (the left end side in FIG. 2A) and a conduit 5 that forms a refrigerant flow path from the large diameter portion 12. (See FIG. 2 (B)) and a cylindrical case portion 11 having a rectangular cross-sectional outer shape. In the center of the large-diameter portion 12, a throttle passage 14 is passed, and a ring groove 13 in which an O-ring 18 for sealing the flow path is mounted is formed on the outer periphery thereof. Through holes 16 are respectively formed on four surfaces of one end portion (large diameter portion 12 side) of the cylindrical case portion 11.
[0021]
The valve body 20 is loosely inserted into the cylindrical case portion 11, and is formed at the other end portion of the cylindrical case portion 11 of the orifice case 10 at the base end portion (the right end portion in FIG. 2A). A stepped rod-like body comprising a columnar part 21 formed with a male threaded part 24 screwed into the female threaded part 17, and a small-diameter tip 22 projected from the cylindrical part 21 toward the large-diameter part 12; In addition, the tip of the small-diameter tip portion 22 is formed with a conical portion for constriction that is disposed to face the constriction passage 14.
[0022]
In the variable orifice device 1 of the first embodiment of the present invention having such a configuration, when assembling it, the valve body 20 made of a rod-shaped body is inserted into the cylindrical case portion 11 of the orifice case 10, The male screw portion 24 formed at the base end portion is screwed into the female screw portion 17 formed at the other end portion of the cylindrical case portion 11 to be positioned and fixed. In this state, as shown in FIG. 3, a throttle passage 14 (large-sized) in which the tip of the valve body 20 (tip of the conical portion for throttle in the small-diameter tip 22) is formed in the large-diameter portion 12 of the orifice case 10. Oppositely arranged at a position separated from the right end of the diameter portion 12 by a predetermined distance (ΔL).
[0023]
In order to incorporate this variable orifice device 1 into the conduit 5 that forms the flow path, it is only necessary to attach an O-ring 18 to the outer periphery of the large-diameter portion 12 of the orifice case 10 and push it into the conduit 5. The cylindrical case portion 11 is sealed between the large diameter portion 12 and the inner peripheral surface of the conduit 5 by the O-ring 18 and has a rectangular cross-sectional outer shape as shown in FIG. Four corner portions are inscribed in the inner peripheral surface of the conduit 5, and four flow paths are formed between the outer peripheral four surfaces of the cylindrical case portion 11 and the inner peripheral surface of the conduit 5.
[0024]
In this case, the separation distance between the tip of the valve body 20 and the throttle passage 14 (the left end of the large diameter portion 12), in other words, as shown in FIG. 3, the length Lb of the cylindrical case portion 11 at that time. The value obtained by subtracting the length La of the valve body 10 from this is the valve opening degree ΔL, and the larger the valve opening degree ΔL, the higher the flow rate of the refrigerant flowing through the throttle passage 14. The valve opening degree ΔL changes due to a difference in expansion / contraction amount generated according to a temperature change of the refrigerant between the resin orifice case 10 and the metal valve body 20.
[0025]
Here, the linear expansion coefficient at 20 ° C. of the orifice case 10 made of resin (POM) is 102 × 10 −6 / ° C., and the linear expansion coefficient of the valve body 20 made of metal (SUS303) is 14.7 ×. The high-pressure refrigerant flows through the conduit 5 constituting the refrigeration circuit from one end side (IN side) to the other end side (OUT side) of the variable orifice device 1.
[0026]
Therefore, the refrigerant passes from the throttle passage 14 through a gap (corresponding to the valve opening degree ΔL) formed between the throttle passage 14 and the tip of the valve body 20, and further, the cylindrical case portion 11. From the four through-holes 16 formed in the above, the liquid flows out into the flow path formed between the four outer peripheral surfaces thereof and the inner peripheral surface of the conduit 5 and flows to the downstream side of the conduit 5.
[0027]
Since the refrigerant that has exited the throttle passage 14 expands and falls in temperature, the temperature of the refrigerant flowing through the variable orifice device 1 gradually decreases. The case 11) is shrunk, but the amount of shrinkage is in accordance with the linear expansion coefficient, and the valve opening is defined as the separation distance between the tip of the valve body 20 and the throttle passage 14 by the difference in the amount of shrinkage. The degree ΔL becomes smaller (see the graph representing the valve opening degree-temperature characteristic in FIG. 4), whereby the flow rate of the refrigerant flowing through the throttle passage 14 is reduced.
Thus, in the variable orifice device 1 of the first embodiment of the present invention, the flow rate of the fluid flowing through the flow path can be made variable according to the temperature of the fluid.
[0028]
  The variable orifice device 1 of the present embodiment is basically composed of two parts, an orifice case 10 and a valve body 20.Because, Simplification of structure, number of partsofIn addition, the valve body 20 can be easily assembled by screwing the orifice case 10 into the orifice case 10 and can be assembled simply by being pushed into the flow path (conduit 5) by attaching an O-ring 18 or the like. Therefore, it is excellent in assembling property, assembling property in a flow path (conduit), and the like, and the manufacturing cost, assembling and assembling cost can be reduced.
[0029]
FIG. 5 is a partially cutaway sectional view showing a state in which the variable orifice device 2 according to the second embodiment of the present invention is incorporated in a conduit, and FIG. 6 is an enlarged sectional view of the main part thereof.
As in the first embodiment, the variable orifice device 2 of the illustrated embodiment is incorporated in a conduit 5 that constitutes a refrigeration cycle in which refrigerant flows from the left side (IN side) to the right side (OUT side) in FIG. However, the material is different from that of the first embodiment, but the material is different from that of the first embodiment, and the shape and configuration are slightly different. And a valve body 30 made of resin (POM).
[0030]
  The valve body 30 is formed with a male threaded portion 34 screwed into a female threaded portion 17 formed at the other end of the orifice case 10 ′ at the base end, and the cylindrical case portion 11 of the orifice case 10 ′. A cylindrical rod 31 that is loosely and freely inserted into the rod, and the rod31A pin-like body 35 connected to the distal end portion of the rod-like body 31. The pin-like body 35 is screwed into the distal end portion of the rod-like body 31 (or can be press-fitted or the like), and is connected to the male screw portion 38. An insertion portion 37 inserted through the passage 14 and a conical portion 36 for drawing provided on the outer end side (IN side) of the insertion portion.
[0031]
In the variable orifice device 2 of the second embodiment having such a configuration, the linear expansion coefficient of the resin valve body 30 is larger than that of the metal orifice case 10 ′, so that the refrigerant temperature decreases. The opening of the valve, which is the separation distance between the conical portion 36 for throttling and the throttling passage 14, is reduced, thereby reducing the flow rate of the refrigerant flowing through the throttling passage 14, and the variable orifice according to the first embodiment. The same effects as those of the device 1 can be obtained.
[0032]
FIG. 7 is a partially cutaway sectional view showing a state where the variable orifice device 3 according to the third embodiment of the present invention is incorporated in a conduit, and FIG. 8 is a diagram showing that the variable orifice device 4 according to the fourth embodiment of the present invention is incorporated in a conduit. It is a partially cutaway sectional view showing a state.
In contrast to the first and second embodiments, the third and fourth variable orifice devices 3 and 4 shown in FIG. 7 and FIG. 8 are the right side (IN side) to the left side (OUT side) in FIG. The variable orifice device 3 of the third embodiment is of the same shape, although the material is different from that of the first embodiment. An orifice case 10 ′ made of metal (SUS303) and a valve body 20 ′ made of resin (POM) are provided. In addition, the variable orifice device 4 of the fourth embodiment includes a resin (POM) orifice case 10 and a metal (SUS303) valve body 30 ′, which are different in material from those of the second embodiment, but of the same shape. Prepare.
[0033]
In the variable orifice devices 3 and 4 of the third and fourth embodiments having such a configuration, the valve body that generates a contracting action in response to a temperature change is disposed in the front stage (position close to the IN side of the refrigerant) of the throttle passage. Therefore, the valve body senses the refrigerant temperature, and the refrigerant temperature on the high pressure side is low at the start of the refrigeration cycle and rises after the start. Therefore, the first embodiment and the second embodiment are different from the orifice case and the valve body. By making this combination the reverse combination, the valve opening increases when the refrigerant temperature at the time of activation is low, and after the activation, the temperature increases and the valve opening decreases. Therefore, the same effect as the variable orifice devices 1 and 2 of the first and second embodiments can be obtained.
[0034]
The variable orifice device 1A of the fifth embodiment shown in FIG. 9 has the same basic configuration as that of the variable orifice device 1 of the first embodiment shown in FIGS. 1 to 3, and a valve 50 having a valve closing function. Attached.
That is, the variable orifice device 1A of the illustrated embodiment is incorporated in a conduit 5 constituting a refrigeration cycle in which refrigerant flows from the left side (IN side) to the right side (OUT side) in FIG. 9A. Similarly to the first embodiment, a valve 50 having a resin orifice case 10 and a metal valve body 20 and having a valve closing function for preventing a reverse flow of the refrigerant is provided at the tip of the valve body 20. It is arranged.
[0035]
The valve 50 having a valve closing function includes a conical valve closing valve body 51 that also opens and closes the throttle passage 14 and also serves as a conical portion for constriction at the distal end portion 22 of the valve body 20, and the valve closing operation. A coil spring 52 is provided as a biasing means that biases the valve body 51 in the direction opposite to the normal flow direction (IN → OUT), that is, in the direction in which the throttle passage 14 is closed.
Here, the coil spring 52 is retracted between the rear surface of the valve closing valve body 51 and the front end portion 22 of the valve body 20, and the center of the rear surface of the valve closing valve body 51 is A guide rod 55 is slidably inserted into a guide hole 56 formed in the center of the distal end of the valve body 20, and the rear surface of the valve closing valve body 51 and the distal end of the valve body 20. Guide tube portions 54 and 56 that project the coil spring 52 in a telescopic manner are projected from the portion 22.
[0036]
In the variable orifice device 1A provided with the valve 50 having such a valve closing function, for example, when the refrigeration cycle is operated, the refrigerant pressure Pi and the downstream side on the upstream side (IN side = compressor side) of the variable orifice device 1A. Since the pressure difference with the refrigerant pressure Po on the (OUT side = evaporator side) is high, the valve 50 having the valve closing function has a valve closing valve body 51 as shown in FIG. Against the biasing force of the coil spring 52, the guide tube portions 53 and 54 are pushed down to a position where they come into contact with each other, and the valve closing valve body 51 and the right end of the throttle passage 14 (of the large diameter portion 12). The right end is the same distance as the separation distance (ΔL) between the conical portion for restriction of the valve body 20 and the right end of the restrictor passage 14 (the right end of the large diameter portion 12) in the variable orifice device 1 of the first embodiment. Only the 14 is an open state.
[0037]
Therefore, during the operation of the refrigeration cycle, as in the first embodiment, the refrigerant that has exited the throttle passage 14 expands and falls, so the temperature of the refrigerant flowing through the variable orifice device 1A gradually decreases, and this refrigerant temperature , The valve body 20 including the valve-closing valve body 51 and the orifice case 10 (the cylindrical case portion 11 thereof) shrink, but the amount of shrinkage depends on the linear expansion coefficient, and the shrinkage The valve opening degree ΔL, which is the separation distance between the tip of the valve body 20 and the throttle passage 14, is reduced by the amount difference, thereby reducing the flow rate of the refrigerant flowing through the throttle passage 14. The flow rate of the refrigerant flowing through is adjusted according to the temperature.
[0038]
On the other hand, when the refrigeration cycle is stopped, the pressure Pi on the upstream side of the variable orifice device 1A rapidly decreases, and the pressure difference with the pressure Po on the downstream side becomes small. At this time, as shown in FIG. 9B, the valve 50 having the valve closing function is reverse to the normal flow direction because the valve closing valve body 51 is urged by the coil spring 52. And the closed passage is closed.
Thus, by providing the valve 50 having a valve closing function, the refrigerant can be prevented from flowing from the upstream side to the downstream side through the variable orifice device 1A, and the inflow of the refrigerant liquid to the evaporator can be prevented. I can do it. In the refrigeration cycle, by preventing the refrigerant liquid from flowing into the evaporator, the liquid flowing into the compressor at the time of restart can be suppressed, and the torque load on the compressor can be reduced.
[0039]
The variable orifice device 1A of the sixth embodiment shown in FIG. 10 has the same basic configuration as the variable orifice device 3 of the third embodiment shown in FIG. 7, but is provided with a valve 60 having a valve closing function. It is.
That is, the variable orifice device 3A of the illustrated embodiment is incorporated in the conduit 5 constituting the refrigeration cycle in which the refrigerant flows from the right side (IN side) to the left side (OUT side) in FIG. In the same manner as in the third embodiment, a metal orifice case 10 ′ and a resin valve body 20 ′ are provided, and a refrigerant is disposed at a position facing the tip of the valve body 20 ′ in the orifice case 10 ′. A valve 60 having a valve closing function for preventing backflow is disposed.
[0040]
The valve 60 having the valve closing function is slidably fitted into the large diameter portion 12 ′ of the orifice case 10 ′ in the cylindrical case portion 11 ′ so as to be slidable between the throttle passage 14 and the valve body 20. A cylindrical valve-closing orifice 61 having a flange-shaped inner edge 61a for receiving and receiving pressure, which opens and closes a gap formed between the throttle conical portion 22a and the valve-closing orifice 61; The O-ring 61b as a sealing material between the orifice case 10 ′ and the valve closing orifice 61 is in the direction opposite to the normal flow direction (IN → OUT), that is, between the throttle passage 14 and the valve body 20 ′. And a coil spring 62 as urging means for urging the gap formed between the aperture conical portion 22a and the closing direction.
[0041]
Here, the coil spring 62 is loaded into the cylindrical valve closing orifice 61 and is compressed between the right end of the large-diameter portion 12 and the bowl-shaped inner edge 61 a of the valve closing orifice 61. Has been.
Also in the variable orifice device 3A in which the valve 50 having the valve closing function is disposed, as in the fifth embodiment, for example, when the refrigeration cycle is operated, the upstream side of the variable orifice device 3A (IN side = compressor side). ) Of the refrigerant Pi and the pressure Po of the refrigerant on the downstream side (OUT side = evaporator side) are high, so that the valve 60 having the valve closing function is as shown in FIG. The valve closing orifice 61 resists the urging force of the coil spring 62 and is pushed down to a position where the rear end is in contact with the left end of the large-diameter portion 12, and the bowl-shaped inner edge 61 a is the valve body 20. The gap formed between the throttling passage 14 and the throttling conical portion 22a of the valve body 20 ′ is opened apart from the throttling conical portion 22a.
[0042]
Therefore, during the operation of the refrigeration cycle, as in the third embodiment, the refrigerant exiting the throttle passage 14 expands and falls in temperature, so the temperature of the refrigerant flowing through the variable orifice device 3A gradually decreases, and this refrigerant temperature The valve body 20 and the orifice case 10 (the cylindrical case portion 11 thereof) are shrunk due to a decrease in the pressure, but the amount of shrinkage is in accordance with the linear expansion coefficient, and only the difference in the amount of shrinkage causes the valve body to shrink. The valve opening degree ΔL, which is the separation distance between the tip of 20 and the throttle passage 14, is reduced, whereby the flow rate of refrigerant flowing through the throttle passage 14 is reduced. Is adjusted according to.
[0043]
On the other hand, when the operation of the refrigeration cycle is stopped, the pressure Pi on the upstream side of the variable orifice device 3A rapidly decreases, and the differential pressure from the pressure Po on the downstream side becomes small. At this time, as shown in FIG. 10B, the valve 60 having the valve closing function has its valve closing orifice 61 in the direction opposite to the normal flow direction by the biasing force of the coil spring 62. The flange-shaped inner edge portion 61a is brought into contact with the constricting conical portion 22a of the valve body 20, and between the constricting passage 14 and the constricting conical portion 22a of the valve body 20 ′. The formed gap is closed.
[0044]
Thus, by providing the valve 60 having the valve closing function, the refrigerant can be prevented from flowing from the upstream side to the downstream side through the variable orifice device 3A, similarly to the fifth embodiment, and the evaporator It is possible to prevent the refrigerant liquid from flowing into. In the refrigeration cycle, by preventing the inflow to the evaporator, the liquid inflow to the compressor at the time of re-operation can be suppressed, and the torque load on the compressor can be reduced.
[0045]
【The invention's effect】
As can be understood from the above description, according to the present invention, the flow rate of the fluid flowing through the flow path can be made variable according to the temperature of the fluid, and the assembly property and the flow path (conduit) can be changed. Therefore, it is possible to provide a variable orifice device that is excellent in assemblability and can be simplified in structure, reduced in the number of parts, and reduced in manufacturing cost.
[Brief description of the drawings]
FIG. 1 is a partially cutaway perspective view showing a state where a variable orifice device according to a first embodiment of the present invention is incorporated in a conduit.
2A is a partially cutaway cross-sectional view of the variable orifice device of the first embodiment, and FIG. 2B is a cross-sectional view taken along the line BB in FIG.
FIG. 3 is an enlarged cross-sectional view of a main part of the variable orifice device of the first embodiment.
FIG. 4 is a graph showing valve opening-temperature characteristics.
FIG. 5 is a partially cutaway sectional view showing a state in which the variable orifice device according to the second embodiment of the present invention is incorporated in a conduit.
FIG. 6 is an enlarged cross-sectional view of a main part of a variable orifice device according to a second embodiment.
FIG. 7 is a partially cutaway sectional view showing a state where the variable orifice device according to the third embodiment of the present invention is incorporated in a conduit.
FIG. 8 is a partially cutaway sectional view showing a state where the variable orifice device according to the fourth embodiment of the present invention is incorporated in a conduit.
FIG. 9 is an enlarged cross-sectional view of the main part showing a state where the variable orifice device according to the fifth embodiment of the present invention is incorporated in a conduit.
FIG. 10 is an enlarged cross-sectional view of a main part showing a state where a variable orifice device according to a sixth embodiment of the present invention is incorporated in a conduit.
[Explanation of symbols]
1-4 Variable orifice device
5 Conduit
10, 10 'orifice case
11, 11 'cylindrical case part
12, 12 'large diameter part
14 Restricted passage
20, 20 'valve body
30, 30 'valve
50, 60 Valve with valve closing function
ΔL Valve opening

Claims

An orifice case and a valve body made of different materials with different linear expansion coefficients are incorporated in a flow path through which a fluid flows , a throttle passage is formed at one end of the orifice case, and the valve body expands and contracts in the orifice case The base end of the valve body is fixed to the other end side of the orifice case, and the flow is caused by a difference in expansion / contraction between the orifice case and the valve body that occurs in response to a change in fluid temperature. fluid flowing through the road is a variable orifice device flow amount Ru flows through the throttle passage in the valve body is variably adjusted,
The orifice case has a large-diameter portion on one end side where an O-ring for sealing the flow channel is mounted on the outer periphery, and extends from the large-diameter portion along the flow channel. A variable orifice device, characterized in that a cylindrical case portion having a rectangular cross-sectional outer shape is formed on the other end side .

The variable orifice device according to claim 1, wherein one of the orifice case and the valve body is made of metal and the other is made of resin.

The valve body is formed with a male screw portion screwed into a female screw portion formed at the other end portion of the orifice case at a base end portion thereof, and at a distal end portion thereof, a conical shape for constriction arranged to face the throttle passage. 3. The variable orifice device according to claim 1, wherein the variable orifice device is formed of a rod-like body having a portion formed thereon.

The valve body includes a rod-like body having a male screw portion screwed into a female screw portion formed at the other end portion of the orifice case at a base end portion thereof, and a distal end portion of the rod-like body connected to the restrictor. The variable orifice device according to claim 1 or 2 , comprising a pin-like body inserted into the passage and having a conical portion for constriction formed on the outer end thereof.

At the position facing the front end of the valve body of the tip or the valve body in the orifice case, according to any of claims 1 to 4, characterized in that the valve having a closing function is provided Variable orifice device.