JP3899719B2

JP3899719B2 - Control valve for variable capacity compressor

Info

Publication number: JP3899719B2
Application number: JP02144099A
Authority: JP
Inventors: 健水藤; 太田　　雅樹; 拓安谷屋; 亮松原
Original assignee: Toyota Industries Corp
Current assignee: Toyota Industries Corp
Priority date: 1999-01-29
Filing date: 1999-01-29
Publication date: 2007-03-28
Anticipated expiration: 2019-01-29
Also published as: EP1024286A2; JP2000220576A; EP1024286A3

Description

【０００１】
【発明の属する技術分野】
本発明は、クランク室の内圧制御に基づいて斜板の傾角を変更し吐出容量を調節可能な容量可変型圧縮機に用いられる制御弁に関する。
【０００２】
【従来の技術および発明が解決しようとする課題】
一般に容量可変型斜板式圧縮機の吐出容量は、クランク室の内圧制御に基づき斜板角度を変更することにより調節される。クランク室内圧の制御方式の一つに抜き側制御がある。これは、吐出圧相当の高圧冷媒ガスをクランク室に常に一定量供給することを前提としてクランク室からのガス放出量を制御することでクランク圧（Ｐｃ）を調節する制御方式である。かかる純粋な抜き側制御ではクランク圧の迅速な昇圧を図ることが困難であり、このことが吐出容量の可変制御性の悪さ（即ち応答遅延）の一因となっていた。このような純粋な抜き側制御の欠点を克服すべく、抜き側制御弁機構と入れ側制御弁機構とを併せ持つ制御弁が従来より提案されており、例えば、特開平５−９９１３６号公報及び特開平１０−１０３２４９号公報にそれぞれ開示の制御弁がある。
【０００３】
特開平５−９９１３６号公報に開示の制御弁は、圧縮機の吐出室とクランク室とを連通する第１連通路を開閉制御する第１弁体２３２と、クランク室と吸入室とを連通する第２連通路を開閉制御する第２弁体２３５と、両弁体を作動させるべく電磁駆動される共通の伝達ロッドとを備え、その伝達ロッドの移動量に応じて第１及び第２弁体の作動領域を完全分離して両弁が同時に開弁しないような構成を採用する。しかしながら、特開平５−９９１３６号公報の制御弁では、略環状の第２弁体２３５に対し前記伝達ロッドを相対摺動可能に内挿しているため、第２弁体２３５が弁座部２３１ｂに着座した後も、その弁体と伝達ロッドとの摺接部位のシール性が不充分となりがちなために、クランク室から吸入室へのガス漏れが避け難いという欠点がある。
【０００４】
他方、特開平１０−１０３２４９号公報に開示の制御弁は、吐出圧領域とクランク室とを繋ぐ給気通路を開閉制御する開閉弁体９０及びそれに一体化された開閉ロッド９１と、クランク室と吸入圧領域とを繋ぐ抽気通路の開度を調節する調整弁体１０２及びそれに一体化された調整ロッド１００とを備え、開閉ロッド９１内に調整ロッド１００を相対移動可能に嵌挿して両弁体９０，１０２を独立に作動可能とすると共に、両ロッドの下端部にそれぞれプランジャを設け、各プランジャを共通のコイルによって電磁付勢可能としている。この特開平１０の制御弁によれば、各弁体が対応する弁座部に着座する限り、前記特開平５の制御弁のような弁体とロッドの間からのガス漏れという問題は存在しない。
【０００５】
ただし、特開平１０−１０３２４９号公報は、特殊なクラッチレスタイプの容量可変型斜板式圧縮機用の制御弁構成を提案しているに過ぎない。即ち、その圧縮機は、駆動軸の内端部領域に吸入通路４２と吸入室４７との連通を遮断可能な遮断体３８を備え、その遮断体３８による遮断動作に基づいて外部冷媒回路での冷媒の流れを停止させるものである。遮断体３８によって吸入通路４２と吸入室４７との連通を阻止した場合に、二つの吸入圧領域（即ち４２と４７）が現われる。それ故、その圧縮機に組み込まれる制御弁においても、上流側にある吸入通路４２の一次吸入圧Ｐｓｅをサンプリングするための感圧室９６と、下流側にある吸入室４７（二次吸入圧Ｐｓｃ）に連通する調整弁室９５とを別々に設けて両室９５，９６を隔壁によって互いに隔絶し、制御弁内部を介して吸入通路４２と吸入室４７とが直接連通しないように配慮している。このため、前記両室９５，９６間の隔壁を貫通して設けなければならない感圧ロッド１０６のロッドクリアランスの管理には慎重を期する必要があるなど、製造管理及びコストの両面で不利は否めない。
【０００６】
本発明の目的は、遮断体を備えない一般的な容量可変型圧縮機に対しても適用可能であると共に、従来の制御弁よりも構造が簡素で製造し易くコスト的にも有利な、抜き側制御弁機構と入れ側制御弁機構とを併せ持つ容量可変型圧縮機の制御弁を提供することにある。
【０００７】
【課題を解決するための手段】
本件の要旨は請求項１，２，３，４及び５にそれぞれ記載した通りである。
請求項１の制御弁によれば、バルブハウジング内に開閉弁機構と調整弁機構とを各々独立して作動可能に組み込むことで、両機構が同一制御弁内で各々の機能を担保しつつ単一構造化される。従って、圧縮機の容量制御構成の簡素化及び小型化と製造コストの低減が図られる。又、第１及び第２プランジャに対して１つのコイルを配設しそのコイルへの通電によって開閉弁体及び調整弁体を同時に電磁付勢する構成としたので、そのコイルを両弁機構の弁体の位置決め制御に共用することができ、構造の簡略化が図られる。更に、調整弁機構を構成する調整弁体及び感圧部材の少なくとも二つを吸入圧が及ぶ同じ室内に配設している。つまり、調整弁体用の弁室と感圧部材用の感圧室とを区別することなく、両室を兼ねる同じ室内に調整弁体と感圧部材とを配設している。この点で特開平１０−１０３２４９号公報の制御弁よりも部屋数が少なくて済み、又、隔壁を貫通する必要のある可動ロッドの数も減ることから、製造管理及びコストの両面で本件の制御弁の方が有利となる。但し、請求項１の制御弁は、遮断体を備えたクラッチレス圧縮機には適さない。
【０００８】
請求項２の制御弁によれば、開閉弁機構の開閉弁体と第１プランジャとを連結するロッドと、調整弁機構の調整弁体と第２プランジャとを連結するロッドとの二つのロッドのうちの一方を筒状に形成するとともに、その一方のロッド内に他方のロッドを相対移動可能に嵌挿した。このため、両弁機構の各弁体をそれらのプランジャの一側方に近接配置することができ、二つの弁機構を備えた制御弁の軸線方向への大型化を抑制できる。又、前記コイルをバルブハウジングの端部に配置することができるため、制御弁を圧縮機のハウジング内に組み込む際に、コイル部を圧縮機ハウジングの外に露出した状態で組み込むことができ、コイルに対する配線作業が容易となる。なお、この構成は、開閉弁体と調整弁体の各々の独立作動を許容する具体的構成でもある。
【０００９】
請求項３の制御弁によれば、調整弁機構の調整弁体と感圧部材とを接離可能に連結しているため、コイルに対する電流の供給が停止され且つ吸入圧が高い場合でも、感圧部材の変位動作に影響されることなく、調整弁体を閉止バネの付勢作用によって調整弁孔に接近する方向に移動させることができる。
【００１０】
請求項４の制御弁によれば、開閉弁機構の開閉弁孔の一端を吐出圧領域に他端をクランク室に連通させ、開閉弁体と第１プランジャとを連結するロッドの断面積（Ｓ１）を開閉弁孔の開口面積（Ｓ２）にほぼ等しくなるようにしたので、開閉弁体の移動方向両側の受圧面積がほぼ等しくなり、該弁体に対して作用する圧力をほぼ完全に相殺できる。従って、開閉弁体に作用する圧力が上昇した場合でも、弁体の移動が円滑になる（詳しくは発明の実施の形態を参照）。
【００１１】
なお、請求項５は、本発明の制御弁が特にクラッチ付きの容量可変型圧縮機に適する旨を明確化したものである。
【００１２】
【発明の実施の形態】
以下に本発明をクラッチ付きの容量可変型斜板式圧縮機に組み込まれる容量制御弁に具体化した一実施形態を図１及び図２を参照しつつ説明する。
【００１３】
（圧縮機本体の概要）
図１に示すように、斜板式圧縮機は、シリンダブロック１と、その前端に接合されたフロントハウジング２と、シリンダブロック１の後端に弁形成体３を介して接合されたリヤハウジング４とを備えている。これら１，２，３及び４は、複数の通しボルト（図示略）により相互に接合固定され、圧縮機のハウジングを構成する。シリンダブロック１とフロントハウジング２とに囲まれた領域にはクランク室５が区画されている。クランク室５内には駆動軸６が、ハウジング内に取り付けられた複数のラジアル軸受けによって回転可能に支持されている。シリンダブロック１の中央凹部内にはコイルバネ７及び後側スラスト軸受け８が配設されている。他方、クランク室５において駆動軸６上には回転支持体１１が一体回転可能に固定され、この回転支持体１１とフロントハウジング２の内側面との間には前側スラスト軸受け９が配設されている。駆動軸６は、バネ７で前方付勢された後側軸受け８と前側軸受け９とによってスラスト支持されている。
【００１４】
駆動軸６の前端部は、電磁クラッチ４０を介して外部駆動源としての車輌エンジンＥに作動連結されている。電磁クラッチ４０は、フロントハウジング２の前方筒部上にベアリング４１により回動可能に支持されたプーリ４２と、環状のソレノイドコイル４３と、駆動軸６の前端域にて板バネ４４付勢された状態で前後摺動可能に設けられたアーマチュア４５とを備えている。図１には、板バネ４４の付勢力に抗してアーマチュア４５がプーリ４２の端面に接合された状態が示されている。コイル４３への通電により生じた電磁力によってアーマチュア４５がプーリ４２の端面に吸引接合されると、動力伝達ベルト４６、プーリ４２及びアーマチュア４５を介してエンジンＥの駆動力が駆動軸６に伝達される。コイル４３への通電停止によって電磁力が消失すれば、アーマチュア４５は板バネ４４の付勢力によってプーリ４２から離間し動力伝達が遮断される。このようにコイル４３への通電制御に基づきエンジン動力が駆動軸６に選択的に伝達される。
【００１５】
更に、クランク室５内にはカムプレートたる斜板１２が収容されている。斜板１２の中央部には挿通孔が貫設され、この挿通孔に駆動軸６が挿通されている。この斜板１２は、連結案内機構としてのヒンジ機構１３を介して回転支持体１１及び駆動軸６に作動連結されている。ヒンジ機構１３は、回転支持体１１のリヤ面に突設されたガイド孔付きの支持アーム１４と、斜板１２のフロント面に突設された球状頭部付きのガイドピン１５とで構成されている。そして、ヒンジ機構１３を構成する支持アーム１４とガイドピン１５との連係および斜板１２の中央挿通孔内での駆動軸６との接触により、斜板１２は駆動軸６と同期回転可能であると共に、駆動軸６の軸線方向へのスライドを伴いながら駆動軸６に対して傾動可能となっている。
【００１６】
回転支持体１１と斜板１２との間において駆動軸６上には、コイル状の傾角減少バネ１６が設けられている。このバネ１６は斜板１２をシリンダブロック１に接近する方向（即ち傾角減少方向）に付勢する。斜板１２よりも後方の駆動軸６上にはサークリップ１７が固着され、該サークリップ１７は斜板１２のそれ以上の後退を規制することで斜板１２の最小傾角（例えば３〜５°）を決定する。他方、斜板１２の最大傾角は、斜板１２のカウンタウェイト部１２ａが回転支持体１１の規制部１１ａに当接することで決定される。
【００１７】
図１に示すように、シリンダブロック１には、駆動軸６を取り囲むように複数のシリンダボア１ａ（一つのみ図示）が形成され、各シリンダボア１ａには片頭型のピストン１８が往復動可能に収容されている。各ピストン１８の端部は一対のシュー１９を介して斜板１２の外周部に係留され、ピストン１８と斜板１２とはシュー１９を介して作動連結されている。
【００１８】
弁形成体３とリヤハウジング４との間には、中心域に位置する吸入室２１と、それを取り囲む吐出室２２とが区画されている。弁形成体３には各シリンダボア１ａに対応して、吸入ポート２３及び同ポート２３を開閉する吸入弁２４、並びに、吐出ポート２５及び同ポート２５を開閉する吐出弁２６が形成されている。吸入ポート２３を介して吸入室２１と各シリンダボア１ａとが連通され、吐出ポート２５を介して各シリンダボア１ａと吐出室２２とが連通される。
【００１９】
図１の斜板式圧縮機では、エンジンＥからの動力供給により駆動軸６が回転されると、それに伴い所定角度に傾斜した斜板１２が回転する。すると、各ピストン１８が斜板の傾角に対応したストロークで往復動され、各シリンダボア１ａでは、吸入室２１（吸入圧Ｐｓの領域）からの冷媒ガスの吸入、圧縮、吐出室２２（吐出圧Ｐｄの領域）への圧縮冷媒ガスの吐出が順次繰り返される。
【００２０】
この圧縮機の斜板１２の傾角決定要因として、斜板回転時の遠心力に基づく回転運動のモーメントと、傾角減少バネ１６の付勢作用に基づくバネ力によるモーメントと、ガス圧によるモーメントの三つがある。斜板１２の慣性乗積は、前記回転運動のモーメントが常に傾角増大方向に作用するように設定されている。他方、ガス圧によるモーメントとは、圧縮行程にあるシリンダボアのピストンに作用する圧縮反力と、吸入行程にあるシリンダボアの内圧と、ピストン背圧にあたるクランク室５の内圧（クランク圧Ｐｃ）との相互関係に基づいて発生するモーメントであり、傾角減少方向に作用する。本実施形態では、クランク圧Ｐｃを高めに維持することで、ガス圧によるモーメントと傾角減少バネ１６のバネ力によるモーメントとの和が前記回転運動による傾角増大方向のモーメントを凌駕し、斜板１２を最小傾角に設定できるように設計されている。又、クランク圧Ｐｃを調節することでガス圧によるモーメントとバネ力によるモーメントとの和を前記回転運動のモーメントとバランスさせ、斜板１２の傾角を前記最小傾角と最大傾角との間の任意の角度に設定することができるようになっている。このように、クランク圧Ｐｃの制御に基づいて斜板１２の傾角が決定され、その傾角に応じて各ピストン１８のストローク即ち圧縮機の吐出容量が可変調節される。
【００２１】
図１及び図２に示すように、クランク圧Ｐｃを制御するための機構は、容量制御弁５０及び各種通路２７，２８及び２９によって構成される。即ち、圧縮機ハウジングには、クランク室５と吸入室２１とを接続する抽気通路２７およびクランク室５と吐出室２２とを接続する給気通路２８が設けられている。抽気通路２７及び給気通路２８の途中には、両通路２７，２８の連通開度を各々独立に制御可能な制御弁５０が設けられている。尚、抽気通路２７及び給気通路２８は制御弁５０とクランク室５との間において共通の通路となっている。又、抽気通路２７のうち制御弁５０と吸入室２１とを繋ぐ部分は、制御弁５０に吸入圧Ｐｓを導くための検圧通路としても機能する。更に圧縮機ハウジングには、給気通路２８とは別に、クランク室５と吐出室２２とを接続する補助給気通路たる連通路２９が設けられている。連通路２９はその途中に固定絞り２９ａを備えている。
【００２２】
（外部冷媒回路及び圧縮機の電子制御構成）
圧縮機の吐出室２２と吸入室２１とは外部冷媒回路３０を介して接続されている。この外部冷媒回路３０は該圧縮機とともに車輌用空調装置の冷房回路を構成する。外部冷媒回路３０には、凝縮器（コンデンサ）３１、温度式の膨張弁３２及び蒸発器（エバポレータ）３３が設けられている。膨張弁３２の開度は、蒸発器３３の出口側に設けられた感温筒の検知温度および蒸発圧力に基づいてフィードバック制御され、膨張弁３２は熱負荷に見合った液冷媒を蒸発器３３に供給して外部冷媒回路３０における冷媒流量を調節する。
【００２３】
更に図２に示すように、蒸発器３３の近傍には温度センサ３４が設置されている。この温度センサ３４は蒸発器３３の温度を検出し、その蒸発器温度情報を制御コンピュータＣに提供する。この制御コンピュータＣは、車輌用空調装置の冷暖房に関する一切の制御を司る。制御コンピュータＣの入力側には、温度センサ３４の他に少なくとも、車輌の室内温度を検出する室温センサ３５、車輌の室内温度を設定するための室温設定器３６、空調装置作動スイッチ３７およびエンジン回転数センサ３８が接続されている。他方、制御コンピュータＣの出力側には、前述の電磁クラッチ４０のソレノイドコイル４３への通電を制御する駆動回路３９Ａと、後述する制御弁５０のコイル８５への通電を制御する駆動回路３９Ｂが接続されている。制御コンピュータＣは、温度センサ３４から得られる蒸発器温度、室温センサ３５から得られる車室内温度、室温設定器３６によって設定された所望室温、空調装置作動スイッチ３７からのＯＮ／ＯＦＦ設定状況、及び、エンジン回転数センサ３８からのエンジン回転数に関する情報等の外部情報に基づき、電磁クラッチ４０を制御すると共に、制御弁５０のコイル８５への適切な通電量を演算する。そして、その演算した電流値の電流を駆動回路３９Ｂから制御弁５０に供給して、制御弁の開度や設定吸入圧Ｐｓｅｔを外部制御する。
【００２４】
（容量制御弁の構成）
図２に示すように、容量制御弁５０は、吐出室２２とクランク室５とを繋ぐ給気通路２８を開閉制御するための開閉弁機構６０と、クランク室５と吸入室２１とを繋ぐ抽気通路２７の開度（又は絞り量）を任意調整するための調整弁機構７０と、両弁機構６０，７０と作動連結されたソレノイド機構８０を備えている。これら三つの機構は、制御弁５０の本体外郭を構成するバルブハウジング５１内に組み込まれている。なお、開閉弁機構６０と調整弁機構７０とは、後述するようにそれぞれ独立して作動可能である。
【００２５】
開閉弁機構６０は、バルブハウジング５１内に上下に隣接して区画された開閉弁室６１及び連通室６２を備えている。開閉弁室６１は給気ポート５２及び給気通路２８を介して吐出室２２に連通され、この開閉弁室６１内には吐出室２２の圧力（吐出圧Ｐｄ）が導かれている。連通室６２は、連通ポート５３及び抽気給気共通の通路２７，２８を介してクランク室５に連通され、この連通室６２内にはクランク圧Ｐｃが導かれている。前記連通室６２の下側（開閉弁室６１側）には、開閉弁孔６３が形成されている。なお、開閉弁室６１、連通室６２及び開閉弁孔６３は、制御弁５０内において給気通路２８の一部を構成する。開閉弁室６１内には開閉弁体６４が垂直方向（制御弁の軸線方向）に移動可能に配設されている。開閉弁体６４の本体部は、その移動に伴い開閉弁孔６３を開閉する。開閉弁体６４の下端部は開閉ロッド６５を介して、第１プランジャとしての開閉プランジャ８２と連結されている。開閉プランジャ８２は、開閉弁室６１の下側のソレノイド室８１内に存在する。開放バネ６６が開閉弁体６４とバルブハウジング５１との間に介装されている。この開放バネ６６は、開閉弁体６４を開閉弁孔６３から離間する方向に付勢し、通常時には開閉弁孔６３を開放状態とする。前記開閉弁体６４、開閉ロッド６５及び開閉プランジャ８２は一体化されており、その一体物は中心に挿通孔６７が貫通した筒形状をなしている。更に開閉弁体６４と開閉プランジャ８２とを連結する開閉ロッド６５の断面積Ｓ１は、開閉弁孔６３の開口面積Ｓ２にほぼ等しくなるように設定されている。
【００２６】
調整弁機構７０は、バルブハウジング５１内において前記連通室６２の上方に位置するように区画された調整弁室７１を備えている。この調整弁室７１は感圧室でもあり、抽気兼感圧ポート５４及び抽気兼検圧通路２７を介して吸入室２１に連通され、この調整弁室（感圧室）７１内には吸入室の圧力（吸入圧Ｐｓ）が導かれている。但し、調整弁室７１内にはバルブハウジング５１の内周壁から軸心に向かって環状のバネ座部５５が突設され、このバネ座部５５によって調整弁室７１は見掛け上、上部領域と下部領域とに区分されるが、これら二領域はバネ座部の中心孔により明らかに連通しており圧力的には等価な同一領域である。調整弁室７１と連通室６２との境界域のハウジング隔壁部（連通室６２の上側）には、環状の弁座を形成する調整弁孔７２が設けられている。なお、連通室６２、調整弁室７１及び調整弁孔７２は、制御弁５０内において抽気通路２７の一部を構成する。
【００２７】
調整弁機構７０の調整弁室７１内には調整弁体７３が垂直方向に移動可能に配設されており、調整弁体７３はその移動に伴い調整弁孔７２の開度を調整する。調整弁体７３の下端部は調整ロッド７４を介して、第２プランジャとしての調整プランジャ８３と連結されている。調整プランジャ８３はソレノイド室８１内に存在する。調整ロッド７４は、連通室６２、開閉弁室６１及びソレノイド室８１の三室にわたり延びており、開閉ロッド６５の中心の挿通孔６７内に相対移動可能に嵌挿されている。閉止バネ７５が調整弁体７３とバネ座部５５との間に介装されている。この閉止バネ７５は、調整弁体７３を調整弁孔７２に接近する方向に付勢し、通常時には調整弁孔７２を閉塞状態とする。調整弁室（感圧室）７１内には更に、感圧部材としてのベローズ７６が配設されている。ベローズ７６の基端部（上端）は弁室７１の天井壁に固定され、先端部（下端）には連結筒７７が固着されている。そして、調整弁体７３上に突設された感圧ロッド７８の先端が前記連結筒７７内に相対移動可能に嵌挿され、べローズ７６が調整弁体７３に対し接離可能に作動連結されている。べローズ７６は、調整弁室（感圧室）７１内に導かれた吸入圧Ｐｓの大きさに応じて自律的に伸縮し、その伸縮動作に基づいて調整弁体７３による調整弁孔７２の開度調節に関与する。
【００２８】
ソレノイド機構８０は、バルブハウジング５１内に区画されたソレノイド室８１を備えている。他方、制御弁５０を圧縮機リヤハウジング４に装着したとき、前記連通室６２とほぼ対応する位置においてバルブハウジング５１の外周面とリヤハウジング４の内壁面との間には環状室５６が形成される。バルブハウジング５１内には、環状室５６とソレノイド室８１とを繋ぐ圧導通路５７が形成されており、連通ポート５３、環状室５６及び圧導通路５７を介してクランク圧Ｐｃがソレノイド室８１に波及している。更にソレノイド室８１の一側（上部領域）には固定鉄心８４が配設されている。ソレノイド室８１内には、固定鉄心８４に近接して、開閉弁機構６０の開閉プランジャ８２及び調整弁機構７０の調整プランジャ８３が収容されている。固定鉄心８４には、両プランジャ８２，８３を取り巻くように一つのコイル８５が装着されている。コイル８５への通電は制御コンピュータＣによって制御される。コイル８５への通電によって生ずる電磁付勢力に基づき、プランジャ８２，８３は各々対応するバネ６６，７５の下向き付勢力に抗して上方（固定鉄心８４への接近方向）に上動される。
【００２９】
なお、コイル８５に対し最小電流値の通電があれば、開閉プランジャ８２の上向き電磁付勢力が開放バネ６６の下向き付勢力を凌駕し、開閉弁機構６０を全閉状態とする。逆にコイル８５への通電がないと、開閉弁機構６０は全開状態となる。従って、開閉弁機構６０は外部制御可能な入れ側ＯＮ／ＯＦＦ弁とみることができる。他方、調整弁機構７０は、コイル８５への通電量に応じて設定吸入圧Ｐｓｅｔを変更可能な設定圧可変型の抜き側内部制御弁とみることができる。
【００３０】
（作用）前記容量可変型圧縮機の動作について説明する。
空調装置作動スイッチ３７がＯＦＦされた状態では、電磁クラッチ４０は遮断状態にありエンジンＥから圧縮機への動力供給はなく圧縮機は運転を停止している。又、この場合には、制御弁５０のコイル８５への通電はなく、両プランジャ８２，８３に対する電磁付勢はない。それ故、開閉弁機構６０では開放バネ６６の作用により開閉弁孔６３が全開状態とされ、調整弁機構７０では閉止バネ７５の作用により調整弁孔７２が閉塞状態とされる。この運転停止状態が長時間続いた場合、圧縮機の各室５，２１，２２の圧力が均一化し、斜板１２は傾角減少バネ１６の付勢作用によって最小傾角に保持される。
【００３１】
空調装置作動スイッチ３７のＯＮ状態のもと、室温センサ３５の検出室温が室温設定器３６による設定温度を超えるとき、制御コンピュータＣは、電磁クラッチのソレノイドコイル４３への通電を行いエンジンＥと圧縮機とを接続して圧縮機を運転させると共に、制御弁５０のコイル８５への通電を行う。コイル８５への電力供給により、開閉プランジャ８２が固定鉄心８４に電磁吸引され、開放バネ６６の下向き付勢力に抗して開閉弁体６４が開閉弁孔６３を閉塞して（図２参照）、給気通路２８が完全に閉じられる。
【００３２】
また、コイル８５への電力供給により、開閉プランジャ８２と調整プランジャ８３との間にも、供給電流値に応じた電磁吸引力が生じる。この電磁吸引力は、閉止バネ７５の付勢力に抗して弁孔７２の開度（以下「抜き側弁開度」という）を増大させる方向の力として、調整ロッド７４を介して調整弁体７３に伝達される。少なくともコイル８５の励磁状況下では、調整プランジャ８３、調整弁体７３及びベローズ７６間には作動連結関係が構築される。そして、調整弁室兼感圧室７１に導入される吸入圧Ｐｓの変動に応じてベローズ７６が変位し、調整弁体７３の位置決めに影響を与える。換言すれば、調整弁機構７０は、少なくとも調整プランジャ８３の受ける電磁付勢力、閉止バネ７５の付勢力及び吸入圧Ｐｓを反映したベローズ７６の付勢力の三者のバランスに基づいて抜き側弁開度を決定する。調整プランジャ８３の電磁付勢力が外部からの通電制御によって可変である点を除けば、調整弁機構７０は、吸入圧Ｐｓに反応して自律的に開度調節を行う通常の内部制御弁として機能する。なお、コイル８５への通電時においても、開閉弁機構６０の開閉弁体６４の位置決め動作と調整弁機構７０の調整弁体７３の位置決め動作とは従属関係になく、それぞれ独立している。
【００３３】
冷房負荷が大きい場合：冷房負荷が大きくなるにつれ、蒸発器３３の出口側圧力（即ち吸入圧Ｐｓ）が次第に大きくなり、例えば室温センサ３５の検出室温と室温設定器３６の設定温度との差が大きくなる。このとき、増大傾向の冷房負荷に見合う圧縮機の吐出能力を確保するため、制御コンピュータＣは、検出室温と設定室温とに基づいて設定吸入圧Ｐｓｅｔを変更すべくコイル８５への供給電流値を制御する。具体的には、検出室温が高いほど供給電流値を大きくし、抜き側弁開度を大きくする方向への調整弁体７３の付勢力を増大させる。このことは制御弁５０の設定吸入圧Ｐｓｅｔを低め誘導（又は再設定）することを意味し、従って、コイル８５への供給電流値の増大により調整弁機構７０は現状よりも低い吸入圧Ｐｓを実現すべく動作する。即ち、調整弁機構７０の自律的動作により抜き側弁開度が大きくなれば、クランク室５から抽気通路２７を経由して吸入室２１に抽出される冷媒ガス量が多くなる。他方、吐出室２２から給気通路２８を経由してクランク室５内に流入する冷媒ガスは、前記開閉弁機構６０によって遮断されている。このため、クランク圧Ｐｃが低下する。又、冷房負荷が大きい状態ではシリンダボア１ａに吸入されるガス圧つまり吸入圧Ｐｓも相対的に高く、シリンダボア１ａの内圧とクランク圧Ｐｃとの差が小さくなる。このため、斜板１２の傾角が大きくなる。
【００３４】
調整弁機構７０の抜き側弁開度が最大になると抽気通路２７の通過断面積が最大化し、クランク室５から抽気通路２７を経由して吸入室２１内に最大量の冷媒ガスが抽出される。そして、クランク圧Ｐｃは吸入室２１の圧力（吸入圧Ｐｓ）とほぼ同一になり、斜板２１の傾角は最大となって吐出容量は最大となる。この最大吐出容量状態では、外部冷媒回路３０の凝縮器３１における凝縮能力の変動によって吐出室２２の圧力（吐出圧Ｐｄ）が大きく上昇することがある。この状態では、開閉弁機構６０の開閉弁室６１に高い吐出圧Ｐｄが導入され、この高い吐出圧Ｐｄが開閉弁体６４に作用することになる。しかしながら、この制御弁５０では、開閉弁体６４と開閉プランジャ８２とを連結する開閉ロッド６５の断面積Ｓ１が、開閉弁孔６３の開口面積Ｓ２とほぼ等しくなっている。このため、開閉弁体６４の可動方向への投影面積つまり開閉弁体６４の受圧面積を考えると、開閉弁体６４が開閉弁孔６３を閉塞した状態において、開閉弁体６４の可動方向両側の受圧面積がほぼ等しいものとなる。その結果、開閉弁体６４の可動方向において、その開閉弁体６４に作用する圧力がほぼ完全に相殺され、吐出圧Ｐｄ及びクランク圧Ｐｃの影響を受けることなく開閉弁体６４の動作が可能となる。
【００３５】
冷房負荷が小さい場合：冷房負荷が小さくなるにつれ、蒸発器３３の出口側圧力（即ちＰｓ）が次第に小さくなり、例えば室温センサ３５の検出温度と室温設定器３６の設定温度との差が小さくなる。このとき、圧縮機の吐出能力を減少傾向の冷房負荷に見合ったものとするため、制御コンピュータＣは、設定吸入圧Ｐｓｅｔを変更すべくコイル８５への供給電流値を制御する。具体的には、検出室温が低いほど供給電流値を小さくし、抜き側弁開度を大きくする方向への調整弁体７３の付勢力を減少させる。このことは制御弁５０の設定吸入圧Ｐｓｅｔを高め誘導（又は再設定）することを意味する。即ち、調整弁機構７０の自律的動作により抜き側弁開度が小さくなれば、クランク室５から抽気通路２７を経由して吸入室２１に抽出される冷媒ガス量が少なくなり、クランク圧Ｐｃが上昇傾向となる。又、冷房負荷が小さい状態ではシリンダボア１ａに吸入されるガス圧つまり吸入圧Ｐｓも相対的に低く、シリンダボア１ａの内圧とクランク圧Ｐｃとの差が大きくなる。このため、斜板１２の傾角が小さくなる。
【００３６】
冷房負荷がない状態に近づいてゆくと、蒸発器３３の温度が次第に低下しフロスト発生をもたらす温度に近づく。温度センサ３４の検出温度が設定温度（蒸発器３３においてフロストを発生しそうな状況を反映した温度）以下になると、制御コンピュータＣは、コイル８５に対する電流の供給を停止する。すると、固定鉄心８４と開閉プランジャ８２との間および開閉プランジャ８２と調整プランジャ８３との間の電磁吸引力が消失し、開閉弁機構６０は開放バネ６６の付勢作用により給気通路２８を全開状態とする一方、調整弁機構７０は閉止バネ７５の付勢作用により抽気通路２７を全閉状態とする。その結果、吐出室２２内の高圧冷媒ガスが給気通路２８を介してクランク室５へ多量に供給されてクランク圧Ｐｃが高くなり、斜板１２が最小傾角状態に移行し、空調装置の冷房動作が抑制される。尚、空調装置作動スイッチ３７がＯＦＦされた場合も、制御コンピュータＣはコイル８５への通電を停止し、斜板１２を最小傾角状態に移行させる。
【００３７】
ソレノイド機構８０が消磁された状態で吸入圧Ｐｓが高くなった場合：吸入圧Ｐｓは検圧通路としての抽気通路２７を介して調整弁室兼感圧室７１にも及んでいるため、吸入圧Ｐｓの高さを反映してベローズ７６は収縮方向（上向き）に変位する。ここで、感圧ロッド７８とベローズの連結筒７７とは接離可能に構成され且つ閉止バネ７５は調整弁体７３を常時下向きに付勢している。このため、ベローズ７６の収縮に伴って感圧ロッド７８とベローズ７６との作動連結が解消され、調整弁体７３に対するベローズ７６の変位の伝達が途絶える。故に、ソレノイド機構８０が消磁された状態で吸入圧Ｐｓが高くなったとしても、吸入圧Ｐｓの影響を受けることなく、調整弁機構７０は調整弁孔７２を閉弁状態に維持することができる。
【００３８】
また、空調装置作動スイッチ３７がＯＮ状態の下、斜板１２が最小傾角位置にある状態において、室温が上昇（冷房負荷が増大）すると、室温センサ３５の検出室温が室温設定器３６の設定温度を越える。すると、制御コンピュータＣは上記温度変化に基づいてソレノイド機構８０の励磁を指令する。ソレノイド機構８０の励磁に伴い、開閉弁機構６０により給気通路２８が閉じられるとともに調整弁機構７０により抽気通路２７が開かれ、クランク圧Ｐｃが次第に減少し、斜板１２が傾角増大方向に復帰する。
【００３９】
以上のように、制御弁５０の開閉弁機構６０及び調整弁機構７０における動作はソレノイド機構８０のコイル８５に対する電流の供給及び停止によって制御される。特に、調整弁機構７０の弁開度（抜き側弁開度）制御の目標値となる設定吸入圧Ｐｓｅｔは、コイル８５への供給電流値を制御することにより適宜変更することができる。そして、圧縮機は、実際の吸入圧Ｐｓが設定吸入圧Ｐｓｅｔに近づきそれを維持すべく斜板１２の傾角を変更してその吐出容量を変更する。
【００４０】
（効果）本実施形態によれば、以下の効果を得ることができる。
○ 上記容量制御弁５０においては、給気通路２８を開閉制御するための開閉弁機構６０と抽気通路２７の開度を任意調整するための調整弁機構７０とが、同じ一つのバルブハウジング５１内に組み込まれている。このため、制御弁５０によれば、開閉弁と調整弁とを別部品で構成しそれらを圧縮機内に各別に組み付けていた従来の圧縮機とは異なり、２つの弁（開閉弁と調整弁）を別々に準備する必要がなく、圧縮機の容量制御構成を従来よりも簡素化して安価に製作することができる。又、開閉弁機構６０と調整弁機構７０とが一体化されているため、容量制御弁５０のための組み込みスペースが比較的小さくてすみ、圧縮機への組み付けが容易となり、圧縮機の小型化に貢献する。
【００４１】
○ 制御弁５０では開閉弁機構６０の開閉プランジャ８２及び調整弁機構７０の調整プランジャ８３の双方に対して１つのコイル８５が共用されているため、制御弁の構造を簡素化できる。
【００４２】
○ 制御弁５０では、開閉弁体６４とプランジャ８２、及び、調整弁体７３とプランジャ８３を開閉ロッド６５及び調整ロッド７４によりそれぞれ連結すると共に、筒状に形成された一方の開閉ロッド６５内に他方の調整ロッド７４を相対移動可能に嵌挿している。このため、両弁体６４，７３をそれらのプランジャ８２，８３の一側方において近接配置することができ、２つの弁機構６０，７０を備えた制御弁５０が軸線方向に大型化するのを抑制することができる。
【００４３】
○ 本実施形態の制御弁５０では、ソレノイド機構８０はバルブハウジング５１の一端に片寄った状態で設けられているため、図１に示すように圧縮機のリヤハウジング４に制御弁５０を組み込んだ際にソレノイド機構８０がリヤハウジング４の外に露出される。このため、この露出状態にあるソレノイド機構８０のコイル８５に対する外部からの配線が容易となる。
【００４４】
○ 制御弁５０の調整弁機構７０を構成する調整弁体７３とベローズ（感圧部材）７６とは、連結筒７７と感圧ロッド７８との挿嵌関係に基づき接離可能に構成されている。このため、コイル８５への給電停止時において吸入圧Ｐｓが高まりべローズ７６が収縮変位したとしても、調整弁体７３は、そのべローズ７６の変位に影響されることなく、閉止バネ７５の作用により調整弁孔７２の閉止位置に保持され得る。
【００４５】
○ 開閉弁体６４と開閉プランジャ８２とを連結する開閉ロッド６５の断面積Ｓ１と、吐出室２２とクランク室５とをつなぐ開閉弁孔６３の開口面積Ｓ２とをほぼ等しくしたため、開閉弁体６４が開閉弁孔６３を閉塞した状態において開閉弁体６４の可動方向両側の受圧面積がほぼ等しくなる結果、開閉弁体６４に作用する圧力をほぼ相殺できる。故に、開閉弁体６４に作用する吐出圧力Ｐｄが大きく上昇した状態においても、吐出圧Ｐｄ及びクランク圧Ｐｃの影響を受けることなく、開閉弁体６４を円滑に移動させることができる。
【００４６】
○ 調整弁機構７０を構成する調整弁体７３及び感圧部材７６を、吸入圧Ｐｓが及ぶ同じ調整弁室兼感圧室７１内に設けたので、制御弁内に区画される部屋数が従来よりも減り、穴加工やロッドクリアランス管理の手間が大幅に減じられ、製造コスト面で有利となる。
【００４７】
○ クランク室５からのガス放出量を主に制御することで斜板角度を調節する抜き側制御では、クランク室５に対し高圧冷媒ガスが常に安定供給されることが斜板角度の制御性（吐出容量の可変制御性）を確保するための前提となる。この点、図１の容量可変型圧縮機には、吐出室２２とクランク室５とを繋ぐ補助給気通路としての連通路２９が形成され、その連通路２９の途中には固定絞り２９ａが設けられている。このため、開閉弁機構６０により給気通路２８が閉じられると共に調整弁機構７０により抽気通路２７の開度（抜き側弁開度）が調整される状態下でも、絞り２９ａ付き連通路２９を介して所定量の冷媒ガスが吐出室２２からクランク室５へ常時供給される。このため、圧縮機の作動時にはクランク圧Ｐｃが常に所定圧以上に保持され、それ故、調整弁機構７０による吐出容量の可変制御性が損なわれることはない。
【００４８】
（別例）本発明の実施形態を以下のように変更してもよい。
○ 調整弁室兼感圧室７１の内部構造を図３又は図４のように変更すること。図３では、感圧ロッド７８が図２の場合よりも短くされると共に、閉止バネ７５が弁室７１の天井壁と調整弁体７３の頭部に形成されたバネ座部７３ａとの間に配設されている。尚、図２の制御弁と同様、感圧ロッド７８は連結筒７７に嵌挿され、接離可能となっている。他方、図４では、弁室７１の天井壁とベローズ７６の基端部（上端部）との間に閉止バネ７５が介在され、ベローズ７６の先端部（下端部）に調整弁体７３が固着されている。図２の制御弁５０における調整弁室兼感圧室７１の内部構造が図３又は図４のように変更されたとしても、前述と同様の作用及び効果を奏する。
【００４９】
○ 調整弁機構７０の調整ロッド７４を筒状に形成し、その調整ロッド７４内に開閉弁機構６０の開閉ロッド６５を相対移動可能に嵌挿すること。
○ 調整弁機構７０で用いる感圧部材としてダイアフラムを採用すること。
【００５０】
○ 図２及び図３における感圧ロッド７８と連結筒７７とを結合すること。
○ 前記容量制御弁５０をクラッチレスタイプの容量可変型圧縮機（電磁クラッチ等のクラッチ機構を介在させることなく外部駆動源から駆動軸６に直接的に動力を伝達するタイプの圧縮機）に適用すること。
【００５１】
（付記）請求項１〜５のいずれか一項に記載の制御弁が組み込まれた容量可変型圧縮機であって、該圧縮機の吐出圧領域とクランク室との間には、前記制御弁の開閉弁機構６０が途中に介在された給気通路２８の他に、固定絞り２９ａの付いた補助給気通路２９が設けられている容量可変型圧縮機。この構成によれば、開閉弁機構により給気通路が閉じられた状態においても、補助給気通路を介して所定量の冷媒ガスが吐出圧領域からクランク室へ供給されるため、吐出容量の可変制御性が損なわれない。
【００５２】
【発明の効果】
以上詳述したように、本発明の制御弁は、遮断体を備えない一般的な容量可変型圧縮機に対し適用可能であると共に、従来の制御弁よりも構造が簡素で製造し易くコスト的にも有利であるという優れた効果を奏する。
【図面の簡単な説明】
【図１】一実施形態に従う容量可変型圧縮機の断面図。
【図２】容量制御弁の断面図。
【図３】容量制御弁の別例を示す部分断面図。
【図４】容量制御弁の別例を示す部分断面図。
【符号の説明】
５…クランク室、１２…斜板、２１…吸入室（吸入圧領域）、２２…吐出室（吐出圧領域）、２７…抽気通路、２８…給気通路、４０…電磁クラッチ、５０…制御弁、５１…バルブハウジング、６０…開閉弁機構、６３…開閉弁孔、６４…開閉弁体、６５…開閉ロッド、６６…開放バネ、７０…調整弁機構、７１…調整弁室兼感圧室（吸入圧が及ぶ同じ室）、７２…調整弁孔、７３…調整弁体、７４…調整ロッド、７５…閉止バネ、７６…べローズ（感圧部材）、８０…ソレノイド機構、８２…開閉プランジャ（第１プランジャ）、８３…調整プランジャ（第２プランジャ）、８５…コイル、Ｅ…車輌エンジン（外部駆動源）、Ｓ１…ロッドの断面積、Ｓ２…弁孔の開口面積。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control valve used in a variable displacement compressor capable of adjusting a discharge capacity by changing an inclination angle of a swash plate based on internal pressure control of a crank chamber.
[0002]
[Background Art and Problems to be Solved by the Invention]
Generally, the discharge capacity of a variable displacement swash plate compressor is adjusted by changing the swash plate angle based on the internal pressure control of the crank chamber. One of the control methods of the crank chamber pressure is the pull-out side control. This is a control method for adjusting the crank pressure (Pc) by controlling the gas discharge amount from the crank chamber on the premise that a constant amount of high-pressure refrigerant gas corresponding to the discharge pressure is always supplied to the crank chamber. Such pure pull-out control makes it difficult to increase the crank pressure quickly, and this contributes to the poor controllability of the discharge capacity (that is, response delay). In order to overcome such drawbacks of pure extraction side control, a control valve having both an extraction side control valve mechanism and an input side control valve mechanism has been proposed, for example, as disclosed in Japanese Patent Laid-Open No. 5-99136 and There is a control valve disclosed in Japanese Laid-Open Patent Publication No. 10-103249.
[0003]
A control valve disclosed in Japanese Patent Laid-Open No. 5-99136 communicates a first valve body 232 that controls opening and closing of a first communication passage that communicates a discharge chamber and a crank chamber of a compressor, and a crank chamber and a suction chamber. A second valve body 235 that controls opening and closing of the second communication path; and a common transmission rod that is electromagnetically driven to actuate both valve bodies, and the first and second valve bodies according to the amount of movement of the transmission rod. The operation region is completely separated and both valves are not opened simultaneously. However, in the control valve disclosed in Japanese Patent Laid-Open No. 5-99136, the transmission rod is inserted into the substantially annular second valve body 235 so as to be relatively slidable, and therefore the second valve body 235 is inserted into the valve seat 231b. Even after seating, there is a drawback that gas leakage from the crank chamber to the suction chamber is difficult to avoid because the sealing performance of the sliding contact portion between the valve body and the transmission rod tends to be insufficient.
[0004]
On the other hand, the control valve disclosed in Japanese Patent Application Laid-Open No. 10-103249 has an open / close valve body 90 for controlling opening / closing of an air supply passage connecting the discharge pressure region and the crank chamber, an open / close rod 91 integrated therewith, a crank chamber, An adjustment valve body 102 for adjusting the opening degree of the extraction passage connecting the suction pressure region and an adjustment rod 100 integrated therewith are provided. The adjustment rod 100 is fitted into the open / close rod 91 so as to be relatively movable, and both valve bodies are inserted. 90 and 102 can be operated independently, and plungers are provided at the lower ends of both rods so that each plunger can be electromagnetically biased by a common coil. According to this control valve of JP-A-10, there is no problem of gas leakage between the valve body and the rod as in the control valve of JP-A-5, as long as each valve body is seated on the corresponding valve seat. .
[0005]
However, Japanese Patent Application Laid-Open No. 10-103249 only proposes a control valve configuration for a special clutchless type variable displacement swash plate compressor. That is, the compressor includes a blocking body 38 capable of blocking the communication between the suction passage 42 and the suction chamber 47 in the inner end region of the drive shaft, and in the external refrigerant circuit based on the blocking operation by the blocking body 38. The flow of the refrigerant is stopped. When the communication between the suction passage 42 and the suction chamber 47 is blocked by the blocking body 38, two suction pressure regions (ie, 42 and 47) appear. Therefore, even in the control valve incorporated in the compressor, the pressure sensing chamber 96 for sampling the primary suction pressure Pse on the upstream side of the suction passage 42 and the suction chamber 47 (secondary suction pressure Psc on the downstream side). And a regulating valve chamber 95 communicating with each other) is separately provided so that both chambers 95 and 96 are separated from each other by a partition wall so that the suction passage 42 and the suction chamber 47 do not directly communicate with each other through the inside of the control valve. . For this reason, it is necessary to be cautious in managing the rod clearance of the pressure-sensitive rod 106 that must be provided through the partition between the two chambers 95 and 96, and there are no disadvantages in terms of manufacturing management and costs. Absent.
[0006]
The object of the present invention is applicable to a general variable displacement compressor that does not include a shut-off body, and has a simpler structure, easier to manufacture, and more advantageous in terms of cost than a conventional control valve. An object of the present invention is to provide a control valve for a variable displacement compressor having both a side control valve mechanism and an inlet side control valve mechanism.
[0007]
[Means for Solving the Problems]
The gist of the present case is as described in claims 1, 2, 3, 4 and 5, respectively.
According to the control valve of the first aspect, the open / close valve mechanism and the regulating valve mechanism are incorporated into the valve housing so as to be independently operable, so that both mechanisms can be used in the same control valve while ensuring their respective functions. One structured. Therefore, the capacity control configuration of the compressor can be simplified and reduced in size, and the manufacturing cost can be reduced. Further, since one coil is provided for the first and second plungers and the on-off valve body and the regulating valve body are electromagnetically energized simultaneously by energizing the coils, the coil is used as a valve for both valve mechanisms. The structure can be shared for body positioning control, and the structure can be simplified. Furthermore, at least two of the regulating valve body and the pressure-sensitive member constituting the regulating valve mechanism are arranged in the same room where the suction pressure reaches. That is, the regulating valve body and the pressure sensitive member are arranged in the same chamber serving as both chambers without distinguishing between the valve chamber for the regulating valve body and the pressure sensing chamber for the pressure sensitive member. In this respect, the number of rooms is smaller than that of the control valve disclosed in Japanese Patent Laid-Open No. 10-103249, and the number of movable rods that need to pass through the partition wall is also reduced. Valves are more advantageous. However, the control valve of claim 1 is not suitable for a clutchless compressor provided with a shut-off body.
[0008]
According to the control valve of the second aspect, the two rods, that is, the rod that connects the opening / closing valve body of the opening / closing valve mechanism and the first plunger, and the rod that connects the adjustment valve body of the adjustment valve mechanism and the second plunger, One of them was formed in a cylindrical shape, and the other rod was fitted and inserted into the one rod so as to be relatively movable. For this reason, each valve body of both valve mechanisms can be arranged close to one side of those plungers, and the size increase of the control valve provided with the two valve mechanisms in the axial direction can be suppressed. In addition, since the coil can be disposed at the end of the valve housing, when the control valve is incorporated in the compressor housing, the coil portion can be incorporated in a state exposed to the outside of the compressor housing. Wiring work becomes easier. This configuration is also a specific configuration that allows the independent operation of the on-off valve body and the regulating valve body.
[0009]
According to the control valve of the third aspect, since the adjustment valve body of the adjustment valve mechanism and the pressure-sensitive member are connected so as to be able to come into contact with and separate from each other, even when the supply of current to the coil is stopped and the suction pressure is high, Without being affected by the displacement operation of the pressure member, the adjustment valve body can be moved in a direction approaching the adjustment valve hole by the biasing action of the closing spring.
[0010]
According to the control valve of the fourth aspect of the present invention, one end of the opening / closing valve hole of the opening / closing valve mechanism communicates with the discharge pressure region and the other end communicates with the crank chamber, and the cross-sectional area of the rod that connects the opening / closing valve body and the first plunger ) Is made substantially equal to the opening area (S2) of the opening / closing valve hole, the pressure receiving areas on both sides in the moving direction of the opening / closing valve body are substantially equal, and the pressure acting on the valve body can be almost completely offset. . Therefore, even when the pressure acting on the on-off valve body rises, the valve body moves smoothly (refer to the embodiment of the invention for details).
[0011]
In addition, claim 5 clarifies that the control valve of the present invention is particularly suitable for a variable displacement compressor with a clutch.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment in which the present invention is embodied in a displacement control valve incorporated in a variable displacement swash plate compressor with a clutch will be described below with reference to FIGS.
[0013]
(Outline of compressor body)
As shown in FIG. 1, the swash plate compressor includes a cylinder block 1, a front housing 2 joined to the front end thereof, and a rear housing 4 joined to the rear end of the cylinder block 1 via a valve forming body 3. It has. These 1, 2, 3 and 4 are joined and fixed to each other by a plurality of through bolts (not shown) to constitute a compressor housing. A crank chamber 5 is defined in a region surrounded by the cylinder block 1 and the front housing 2. A drive shaft 6 is rotatably supported in the crank chamber 5 by a plurality of radial bearings mounted in the housing. A coil spring 7 and a rear thrust bearing 8 are disposed in the central recess of the cylinder block 1. On the other hand, a rotation support 11 is fixed on the drive shaft 6 in the crank chamber 5 so as to be integrally rotatable, and a front thrust bearing 9 is disposed between the rotation support 11 and the inner surface of the front housing 2. Yes. The drive shaft 6 is thrust supported by a rear bearing 8 and a front bearing 9 urged forward by a spring 7.
[0014]
A front end portion of the drive shaft 6 is operatively connected to a vehicle engine E as an external drive source via an electromagnetic clutch 40. The electromagnetic clutch 40 is biased by a leaf spring 44 in a front end region of the drive shaft 6, a pulley 42 rotatably supported by a bearing 41 on the front cylinder portion of the front housing 2, an annular solenoid coil 43, and a drive shaft 6. And an armature 45 provided to be slidable back and forth in the state. FIG. 1 shows a state in which the armature 45 is joined to the end face of the pulley 42 against the urging force of the leaf spring 44. When the armature 45 is attracted and joined to the end face of the pulley 42 by the electromagnetic force generated by energizing the coil 43, the driving force of the engine E is transmitted to the drive shaft 6 through the power transmission belt 46, the pulley 42 and the armature 45. The If the electromagnetic force disappears due to the energization stop of the coil 43, the armature 45 is separated from the pulley 42 by the urging force of the leaf spring 44 and the power transmission is interrupted. In this way, engine power is selectively transmitted to the drive shaft 6 based on energization control to the coil 43.
[0015]
Further, a swash plate 12 as a cam plate is accommodated in the crank chamber 5. An insertion hole is provided in the center of the swash plate 12, and the drive shaft 6 is inserted through the insertion hole. The swash plate 12 is operatively connected to the rotary support 11 and the drive shaft 6 via a hinge mechanism 13 as a connection guide mechanism. The hinge mechanism 13 includes a support arm 14 with a guide hole protruding from the rear surface of the rotary support 11 and a guide pin 15 with a spherical head protruding from the front surface of the swash plate 12. Yes. The swash plate 12 can rotate synchronously with the drive shaft 6 by the linkage between the support arm 14 and the guide pin 15 constituting the hinge mechanism 13 and the contact with the drive shaft 6 in the central insertion hole of the swash plate 12. At the same time, the drive shaft 6 can be tilted with respect to the drive shaft 6 while being slid in the axial direction.
[0016]
On the drive shaft 6 between the rotary support 11 and the swash plate 12, a coil-shaped tilt angle reducing spring 16 is provided. The spring 16 urges the swash plate 12 in a direction approaching the cylinder block 1 (that is, a direction in which the tilt angle decreases). A circlip 17 is fixed on the drive shaft 6 rearward of the swash plate 12, and the circlip 17 restricts further retreat of the swash plate 12 so that the minimum inclination angle of the swash plate 12 (for example, 3 to 5 °). ). On the other hand, the maximum inclination angle of the swash plate 12 is determined by the counterweight portion 12 a of the swash plate 12 coming into contact with the regulating portion 11 a of the rotation support 11.
[0017]
As shown in FIG. 1, the cylinder block 1 is formed with a plurality of cylinder bores 1a (only one is shown) so as to surround the drive shaft 6, and a single-headed piston 18 is accommodated in each cylinder bore 1a so as to reciprocate. Has been. The end portions of the pistons 18 are anchored to the outer peripheral portion of the swash plate 12 via a pair of shoes 19, and the piston 18 and the swash plate 12 are operatively connected via the shoes 19.
[0018]
A suction chamber 21 located in the central region and a discharge chamber 22 surrounding the suction chamber 21 are defined between the valve forming body 3 and the rear housing 4. Corresponding to each cylinder bore 1a, the valve forming body 3 is formed with a suction port 23 and a suction valve 24 for opening and closing the port 23, and a discharge port 25 and a discharge valve 26 for opening and closing the port 25. The suction chamber 21 communicates with each cylinder bore 1 a via the suction port 23, and each cylinder bore 1 a communicates with the discharge chamber 22 via the discharge port 25.
[0019]
In the swash plate compressor of FIG. 1, when the drive shaft 6 is rotated by the power supply from the engine E, the swash plate 12 inclined at a predetermined angle is rotated accordingly. Then, each piston 18 is reciprocated at a stroke corresponding to the inclination angle of the swash plate, and in each cylinder bore 1a, the refrigerant gas is sucked in, compressed, and discharged from the suction chamber 21 (region of suction pressure Ps) (discharge pressure Pd). The discharge of the compressed refrigerant gas to (region) is sequentially repeated.
[0020]
The factors that determine the tilt angle of the swash plate 12 of this compressor are the moment of the rotational motion based on the centrifugal force when the swash plate rotates, the moment due to the spring force based on the biasing action of the tilt angle reducing spring 16, and the moment due to the gas pressure. There is one. The inertial product of the swash plate 12 is set so that the moment of the rotational motion always acts in the inclination increasing direction. On the other hand, the moment due to the gas pressure is the mutual reaction between the compression reaction force acting on the piston of the cylinder bore in the compression stroke, the internal pressure of the cylinder bore in the suction stroke, and the internal pressure (crank pressure Pc) of the crank chamber 5 corresponding to the piston back pressure. This moment is generated based on the relationship and acts in the direction of decreasing the tilt angle. In the present embodiment, by maintaining the crank pressure Pc high, the sum of the moment due to the gas pressure and the moment due to the spring force of the inclination decreasing spring 16 surpasses the moment in the inclination increasing direction due to the rotational motion, and the swash plate 12 Is designed to be set to the minimum tilt angle. Further, by adjusting the crank pressure Pc, the sum of the moment caused by the gas pressure and the moment caused by the spring force is balanced with the moment of the rotational motion, and the inclination angle of the swash plate 12 is set to an arbitrary angle between the minimum inclination angle and the maximum inclination angle. The angle can be set. In this manner, the inclination angle of the swash plate 12 is determined based on the control of the crank pressure Pc, and the stroke of each piston 18, that is, the discharge capacity of the compressor is variably adjusted according to the inclination angle.
[0021]
As shown in FIGS. 1 and 2, the mechanism for controlling the crank pressure Pc includes a capacity control valve 50 and various passages 27, 28 and 29. In other words, the compressor housing is provided with an extraction passage 27 that connects the crank chamber 5 and the suction chamber 21 and an air supply passage 28 that connects the crank chamber 5 and the discharge chamber 22. In the middle of the extraction passage 27 and the supply passage 28, a control valve 50 is provided which can independently control the opening degree of the passages 27 and 28. The extraction passage 27 and the supply passage 28 are common passages between the control valve 50 and the crank chamber 5. Further, a portion of the extraction passage 27 that connects the control valve 50 and the suction chamber 21 also functions as a pressure detection passage for guiding the suction pressure Ps to the control valve 50. In addition to the air supply passage 28, the compressor housing is provided with a communication passage 29 as an auxiliary air supply passage that connects the crank chamber 5 and the discharge chamber 22. The communication passage 29 is provided with a fixed throttle 29a in the middle thereof.
[0022]
(External refrigerant circuit and electronic control configuration of compressor)
The discharge chamber 22 and the suction chamber 21 of the compressor are connected via an external refrigerant circuit 30. The external refrigerant circuit 30 constitutes a cooling circuit of a vehicle air conditioner together with the compressor. The external refrigerant circuit 30 is provided with a condenser (condenser) 31, a temperature type expansion valve 32, and an evaporator (evaporator) 33. The opening degree of the expansion valve 32 is feedback-controlled based on the temperature detected by the temperature sensing cylinder provided on the outlet side of the evaporator 33 and the evaporation pressure, and the expansion valve 32 supplies liquid refrigerant corresponding to the heat load to the evaporator 33. Supply the refrigerant flow rate in the external refrigerant circuit 30 to adjust.
[0023]
Further, as shown in FIG. 2, a temperature sensor 34 is installed in the vicinity of the evaporator 33. The temperature sensor 34 detects the temperature of the evaporator 33 and provides the temperature information of the evaporator to the control computer C. This control computer C manages all the control related to the cooling and heating of the vehicle air conditioner. On the input side of the control computer C, in addition to the temperature sensor 34, at least a room temperature sensor 35 for detecting the room temperature of the vehicle, a room temperature setting device 36 for setting the room temperature of the vehicle, an air conditioner operation switch 37, and an engine rotation A number sensor 38 is connected. On the other hand, on the output side of the control computer C, a drive circuit 39A for controlling energization to the solenoid coil 43 of the electromagnetic clutch 40 and a drive circuit 39B for controlling energization to the coil 85 of the control valve 50 described later are connected. Has been. The control computer C includes an evaporator temperature obtained from the temperature sensor 34, a vehicle interior temperature obtained from the room temperature sensor 35, a desired room temperature set by the room temperature setter 36, an ON / OFF setting status from the air conditioner operation switch 37, and Based on external information such as information on the engine speed from the engine speed sensor 38, the electromagnetic clutch 40 is controlled, and an appropriate energization amount to the coil 85 of the control valve 50 is calculated. Then, the current of the calculated current value is supplied from the drive circuit 39B to the control valve 50, and the opening degree of the control valve and the set suction pressure Pset are externally controlled.
[0024]
(Configuration of capacity control valve)
As shown in FIG. 2, the capacity control valve 50 includes an opening / closing valve mechanism 60 for controlling the opening and closing of the air supply passage 28 that connects the discharge chamber 22 and the crank chamber 5, and a bleed air that connects the crank chamber 5 and the suction chamber 21. An adjustment valve mechanism 70 for arbitrarily adjusting the opening degree (or throttle amount) of the passage 27 and a solenoid mechanism 80 operatively connected to both valve mechanisms 60 and 70 are provided. These three mechanisms are incorporated in a valve housing 51 that constitutes the main body of the control valve 50. The on-off valve mechanism 60 and the regulating valve mechanism 70 can be operated independently as will be described later.
[0025]
The on-off valve mechanism 60 includes an on-off valve chamber 61 and a communication chamber 62 which are partitioned in the valve housing 51 adjacent to each other in the vertical direction. The on-off valve chamber 61 communicates with the discharge chamber 22 through the air supply port 52 and the air supply passage 28, and the pressure (discharge pressure Pd) of the discharge chamber 22 is guided into the on-off valve chamber 61. The communication chamber 62 communicates with the crank chamber 5 through the communication port 53 and the passages 27 and 28 common to the bleed air supply, and the crank pressure Pc is introduced into the communication chamber 62. An open / close valve hole 63 is formed below the communication chamber 62 (on the open / close valve chamber 61 side). The on-off valve chamber 61, the communication chamber 62, and the on-off valve hole 63 constitute a part of the air supply passage 28 in the control valve 50. An on-off valve body 64 is disposed in the on-off valve chamber 61 so as to be movable in the vertical direction (the axial direction of the control valve). The main body of the on-off valve body 64 opens and closes the on-off valve hole 63 as it moves. The lower end of the opening / closing valve body 64 is connected to an opening / closing plunger 82 as a first plunger via an opening / closing rod 65. The opening / closing plunger 82 exists in the solenoid chamber 81 below the opening / closing valve chamber 61. An opening spring 66 is interposed between the opening / closing valve body 64 and the valve housing 51. The opening spring 66 urges the opening / closing valve body 64 in a direction away from the opening / closing valve hole 63, and normally opens the opening / closing valve hole 63. The on-off valve body 64, the on-off rod 65, and the on-off plunger 82 are integrated, and the integrated body has a cylindrical shape with an insertion hole 67 passing through the center. Furthermore, the cross-sectional area S1 of the opening / closing rod 65 that connects the opening / closing valve body 64 and the opening / closing plunger 82 is set to be substantially equal to the opening area S2 of the opening / closing valve hole 63.
[0026]
The adjustment valve mechanism 70 includes an adjustment valve chamber 71 that is partitioned in the valve housing 51 so as to be positioned above the communication chamber 62. The regulating valve chamber 71 is also a pressure sensing chamber, and communicates with the suction chamber 21 via the bleed / pressure sensing port 54 and the bleed / pressure sensing passage 27, and the regulating valve chamber (pressure sensing chamber) 71 has a suction chamber. Pressure (suction pressure Ps). However, an annular spring seat portion 55 projects from the inner peripheral wall of the valve housing 51 toward the axial center in the adjustment valve chamber 71, and the adjustment valve chamber 71 apparently appears in the upper region and the lower portion by the spring seat portion 55. Although these are divided into regions, these two regions clearly communicate with each other through the central hole of the spring seat, and are the same region equivalent in terms of pressure. An adjustment valve hole 72 that forms an annular valve seat is provided in the housing partition wall (upper side of the communication chamber 62) in the boundary area between the adjustment valve chamber 71 and the communication chamber 62. The communication chamber 62, the adjustment valve chamber 71 and the adjustment valve hole 72 constitute a part of the extraction passage 27 in the control valve 50.
[0027]
An adjustment valve body 73 is disposed in the adjustment valve chamber 71 of the adjustment valve mechanism 70 so as to be movable in the vertical direction, and the adjustment valve body 73 adjusts the opening degree of the adjustment valve hole 72 in accordance with the movement. A lower end portion of the adjustment valve body 73 is connected to an adjustment plunger 83 as a second plunger via an adjustment rod 74. The adjustment plunger 83 exists in the solenoid chamber 81. The adjustment rod 74 extends over the three chambers of the communication chamber 62, the on-off valve chamber 61, and the solenoid chamber 81, and is inserted into the insertion hole 67 at the center of the on-off rod 65 so as to be relatively movable. A closing spring 75 is interposed between the adjustment valve body 73 and the spring seat portion 55. The closing spring 75 urges the adjustment valve body 73 in a direction approaching the adjustment valve hole 72, and normally closes the adjustment valve hole 72. A bellows 76 as a pressure sensitive member is further provided in the regulating valve chamber (pressure sensitive chamber) 71. The base end portion (upper end) of the bellows 76 is fixed to the ceiling wall of the valve chamber 71, and the connecting cylinder 77 is fixed to the distal end portion (lower end). Then, the tip of the pressure-sensitive rod 78 protruding from the adjusting valve body 73 is fitted into the connecting cylinder 77 so as to be relatively movable, and the bellows 76 is operatively connected to the adjusting valve body 73 so as to be able to contact and separate. ing. The bellows 76 expands and contracts autonomously according to the magnitude of the suction pressure Ps guided into the adjustment valve chamber (pressure sensing chamber) 71, and the adjustment valve hole 72 of the adjustment valve body 73 is formed based on the expansion and contraction operation. Involved in opening adjustment.
[0028]
The solenoid mechanism 80 includes a solenoid chamber 81 defined in the valve housing 51. On the other hand, when the control valve 50 is mounted on the compressor rear housing 4, an annular chamber 56 is formed between the outer peripheral surface of the valve housing 51 and the inner wall surface of the rear housing 4 at a position substantially corresponding to the communication chamber 62. The A pressure conduction path 57 that connects the annular chamber 56 and the solenoid chamber 81 is formed in the valve housing 51, and the crank pressure Pc is transferred to the solenoid chamber 81 via the communication port 53, the annular chamber 56, and the pressure conduction path 57. It is spreading. Further, a fixed iron core 84 is disposed on one side (upper region) of the solenoid chamber 81. In the solenoid chamber 81, an open / close plunger 82 of the open / close valve mechanism 60 and an adjustment plunger 83 of the adjustment valve mechanism 70 are accommodated in the vicinity of the fixed iron core 84. One coil 85 is attached to the fixed iron core 84 so as to surround both plungers 82 and 83. Energization of the coil 85 is controlled by the control computer C. Based on the electromagnetic urging force generated by energizing the coil 85, the plungers 82 and 83 are moved upward (in the approaching direction to the fixed iron core 84) against the downward urging forces of the corresponding springs 66 and 75, respectively.
[0029]
If the coil 85 is energized with the minimum current value, the upward electromagnetic biasing force of the opening / closing plunger 82 surpasses the downward biasing force of the release spring 66, and the open / close valve mechanism 60 is fully closed. Conversely, if the coil 85 is not energized, the on-off valve mechanism 60 is fully opened. Therefore, the on-off valve mechanism 60 can be regarded as an input side ON / OFF valve that can be controlled externally. On the other hand, the regulating valve mechanism 70 can be regarded as a variable set-pressure-side extraction-side internal control valve that can change the set suction pressure Pset in accordance with the energization amount to the coil 85.
[0030]
(Operation) The operation of the variable capacity compressor will be described.
In a state where the air conditioner operation switch 37 is turned off, the electromagnetic clutch 40 is in a disconnected state, and no power is supplied from the engine E to the compressor, and the compressor stops operating. In this case, the coil 85 of the control valve 50 is not energized, and there is no electromagnetic urging for the plungers 82 and 83. Therefore, in the on-off valve mechanism 60, the on-off valve hole 63 is fully opened by the action of the opening spring 66, and in the adjusting valve mechanism 70, the adjustment valve hole 72 is in the closed state by the action of the closing spring 75. When this operation stop state continues for a long time, the pressures in the compressor chambers 5, 21, and 22 become uniform, and the swash plate 12 is held at the minimum inclination angle by the biasing action of the inclination angle reduction spring 16.
[0031]
When the detected room temperature of the room temperature sensor 35 exceeds the temperature set by the room temperature setter 36 under the ON state of the air conditioner operation switch 37, the control computer C energizes the solenoid coil 43 of the electromagnetic clutch and compresses it with the engine E. The compressor is operated by connecting to the machine, and the coil 85 of the control valve 50 is energized. By supplying power to the coil 85, the opening / closing plunger 82 is electromagnetically attracted to the fixed iron core 84, and the opening / closing valve body 64 closes the opening / closing valve hole 63 against the downward biasing force of the opening spring 66 (see FIG. 2). The supply passage 28 is completely closed.
[0032]
Further, due to the power supply to the coil 85, an electromagnetic attractive force corresponding to the supply current value is generated between the open / close plunger 82 and the adjustment plunger 83. This electromagnetic attraction force is a force in the direction of increasing the opening degree of the valve hole 72 (hereinafter referred to as “extraction side valve opening degree”) against the urging force of the closing spring 75, and the adjustment valve body via the adjustment rod 74. 73. At least under the excitation state of the coil 85, an operating connection relationship is established among the adjustment plunger 83, the adjustment valve body 73, and the bellows 76. Then, the bellows 76 is displaced according to the fluctuation of the suction pressure Ps introduced into the regulating valve chamber / pressure sensing chamber 71, and affects the positioning of the regulating valve body 73. In other words, the adjustment valve mechanism 70 opens the extraction side valve based on the balance of at least the electromagnetic urging force received by the adjustment plunger 83, the urging force of the closing spring 75, and the urging force of the bellows 76 reflecting the suction pressure Ps. Determine the degree. Except for the point that the electromagnetic urging force of the adjustment plunger 83 is variable by external energization control, the adjustment valve mechanism 70 functions as a normal internal control valve that autonomously adjusts the opening degree in response to the suction pressure Ps. To do. Even when the coil 85 is energized, the positioning operation of the on-off valve body 64 of the on-off valve mechanism 60 and the positioning operation of the adjustment valve body 73 of the adjustment valve mechanism 70 are independent of each other and are independent of each other.
[0033]
When the cooling load is large: As the cooling load increases, the outlet side pressure of the evaporator 33 (that is, the suction pressure Ps) gradually increases. For example, the difference between the detected room temperature of the room temperature sensor 35 and the set temperature of the room temperature setter 36 is growing. At this time, in order to ensure the discharge capacity of the compressor commensurate with the increasing cooling load, the control computer C changes the supply current value to the coil 85 to change the set suction pressure Pset based on the detected room temperature and the set room temperature. Control. Specifically, the supply current value is increased as the detected room temperature is higher, and the urging force of the adjustment valve body 73 in the direction of increasing the outlet valve opening is increased. This means that the set intake pressure Pset of the control valve 50 is lowered and guided (or reset). Therefore, the adjustment valve mechanism 70 reduces the intake pressure Ps lower than the current state by increasing the supply current value to the coil 85. Operates to achieve. That is, when the opening degree of the extraction side valve is increased by the autonomous operation of the regulating valve mechanism 70, the amount of refrigerant gas extracted from the crank chamber 5 to the suction chamber 21 via the extraction passage 27 increases. On the other hand, the refrigerant gas flowing into the crank chamber 5 from the discharge chamber 22 via the air supply passage 28 is blocked by the on-off valve mechanism 60. For this reason, the crank pressure Pc decreases. Further, when the cooling load is large, the gas pressure sucked into the cylinder bore 1a, that is, the suction pressure Ps is also relatively high, and the difference between the internal pressure of the cylinder bore 1a and the crank pressure Pc becomes small. For this reason, the inclination angle of the swash plate 12 increases.
[0034]
When the outlet side valve opening degree of the regulating valve mechanism 70 is maximized, the passage sectional area of the extraction passage 27 is maximized, and the maximum amount of refrigerant gas is extracted from the crank chamber 5 into the suction chamber 21 via the extraction passage 27. . The crank pressure Pc becomes substantially the same as the pressure in the suction chamber 21 (suction pressure Ps), the inclination angle of the swash plate 21 is maximized, and the discharge capacity is maximized. In this maximum discharge capacity state, the pressure in the discharge chamber 22 (discharge pressure Pd) may greatly increase due to fluctuations in the condensing capacity in the condenser 31 of the external refrigerant circuit 30. In this state, a high discharge pressure Pd is introduced into the on-off valve chamber 61 of the on-off valve mechanism 60, and this high discharge pressure Pd acts on the on-off valve body 64. However, in this control valve 50, the sectional area S1 of the opening / closing rod 65 that connects the opening / closing valve body 64 and the opening / closing plunger 82 is substantially equal to the opening area S2 of the opening / closing valve hole 63. For this reason, when considering the projected area of the on-off valve body 64 in the movable direction, that is, the pressure receiving area of the on-off valve body 64, the open / close valve body 64 is closed on both sides of the on-off valve body 64 in the movable direction in the closed state. The pressure receiving area is substantially equal. As a result, in the movable direction of the on-off valve body 64, the pressure acting on the on-off valve body 64 is almost completely offset, and the on-off valve body 64 can be operated without being affected by the discharge pressure Pd and the crank pressure Pc. Become.
[0035]
When the cooling load is small: As the cooling load decreases, the outlet side pressure (ie, Ps) of the evaporator 33 gradually decreases, and for example, the difference between the detected temperature of the room temperature sensor 35 and the set temperature of the room temperature setter 36 decreases. . At this time, the control computer C controls the supply current value to the coil 85 so as to change the set suction pressure Pset in order to make the discharge capacity of the compressor commensurate with the decreasing cooling load. Specifically, the lower the detected room temperature, the smaller the supply current value, and the urging force of the adjustment valve body 73 in the direction of increasing the removal side valve opening is decreased. This means that the set suction pressure Pset of the control valve 50 is increased and guided (or reset). That is, if the valve opening on the outlet side is reduced by the autonomous operation of the regulating valve mechanism 70, the amount of refrigerant gas extracted from the crank chamber 5 via the extraction passage 27 to the suction chamber 21 is reduced, and the crank pressure Pc is reduced. It becomes an upward trend. Further, when the cooling load is small, the gas pressure sucked into the cylinder bore 1a, that is, the suction pressure Ps is relatively low, and the difference between the internal pressure of the cylinder bore 1a and the crank pressure Pc becomes large. For this reason, the inclination angle of the swash plate 12 becomes small.
[0036]
As the temperature approaches the state where there is no cooling load, the temperature of the evaporator 33 gradually decreases and approaches the temperature causing frost generation. When the temperature detected by the temperature sensor 34 is equal to or lower than a set temperature (a temperature reflecting a situation in which the evaporator 33 is likely to generate frost), the control computer C stops supplying current to the coil 85. Then, the electromagnetic attractive force between the fixed iron core 84 and the open / close plunger 82 and between the open / close plunger 82 and the adjustment plunger 83 disappears, and the open / close valve mechanism 60 fully opens the air supply passage 28 by the biasing action of the open spring 66. On the other hand, the regulating valve mechanism 70 causes the bleed passage 27 to be fully closed by the urging action of the closing spring 75. As a result, a large amount of high-pressure refrigerant gas in the discharge chamber 22 is supplied to the crank chamber 5 via the air supply passage 28, the crank pressure Pc increases, the swash plate 12 shifts to the minimum inclination state, and the air conditioner is cooled. Operation is suppressed. Even when the air conditioner operation switch 37 is turned off, the control computer C stops energizing the coil 85 and shifts the swash plate 12 to the minimum inclination state.
[0037]
When the suction pressure Ps becomes high in a state where the solenoid mechanism 80 is demagnetized: Since the suction pressure Ps reaches the regulating valve chamber / pressure sensing chamber 71 via the extraction passage 27 as a pressure detection passage, the suction pressure Ps. Reflecting the height of Ps, the bellows 76 is displaced in the contraction direction (upward). Here, the pressure-sensitive rod 78 and the connecting cylinder 77 of the bellows are configured to be able to contact and separate, and the closing spring 75 always urges the adjusting valve body 73 downward. For this reason, the operation connection between the pressure-sensitive rod 78 and the bellows 76 is canceled with the contraction of the bellows 76, and the transmission of the displacement of the bellows 76 to the adjustment valve body 73 is interrupted. Therefore, even if the suction pressure Ps becomes high when the solenoid mechanism 80 is demagnetized, the adjustment valve mechanism 70 can maintain the adjustment valve hole 72 in the closed state without being affected by the suction pressure Ps. .
[0038]
Further, when the room temperature rises (the cooling load increases) in a state where the air conditioner operation switch 37 is ON and the swash plate 12 is at the minimum tilt position, the room temperature detected by the room temperature sensor 35 becomes the set temperature of the room temperature setter 36. Over. Then, the control computer C commands excitation of the solenoid mechanism 80 based on the temperature change. With the excitation of the solenoid mechanism 80, the air supply passage 28 is closed by the on-off valve mechanism 60 and the bleed passage 27 is opened by the adjustment valve mechanism 70, the crank pressure Pc gradually decreases, and the swash plate 12 returns to the direction of increasing the tilt angle. To do.
[0039]
As described above, the operations of the on-off valve mechanism 60 and the regulating valve mechanism 70 of the control valve 50 are controlled by supplying and stopping the current to the coil 85 of the solenoid mechanism 80. In particular, the set suction pressure Pset, which is a target value for controlling the valve opening (extraction-side valve opening) of the regulating valve mechanism 70, can be changed as appropriate by controlling the current value supplied to the coil 85. Then, the compressor changes the discharge capacity by changing the inclination angle of the swash plate 12 so that the actual suction pressure Ps approaches the set suction pressure Pset and is maintained.
[0040]
(Effect) According to this embodiment, the following effects can be obtained.
In the capacity control valve 50, the opening / closing valve mechanism 60 for controlling opening / closing of the air supply passage 28 and the adjusting valve mechanism 70 for arbitrarily adjusting the opening degree of the extraction passage 27 are provided in the same valve housing 51. Built in. For this reason, according to the control valve 50, unlike the conventional compressor which comprised the on-off valve and the regulating valve as separate parts and assembled them separately in the compressor, there are two valves (the on-off valve and the regulating valve). Need not be prepared separately, and the capacity control configuration of the compressor can be simplified and manufactured at a low cost. Further, since the on-off valve mechanism 60 and the regulating valve mechanism 70 are integrated, the space for installing the capacity control valve 50 is relatively small, and it is easy to assemble the compressor, and the compressor can be downsized. To contribute.
[0041]
In the control valve 50, since one coil 85 is shared by both the opening / closing plunger 82 of the opening / closing valve mechanism 60 and the adjustment plunger 83 of the adjustment valve mechanism 70, the structure of the control valve can be simplified.
[0042]
In the control valve 50, the on-off valve body 64 and the plunger 82, and the adjusting valve body 73 and the plunger 83 are connected to each other by the on-off rod 65 and the adjusting rod 74, respectively, and in the one on-off rod 65 formed in a cylindrical shape. The other adjustment rod 74 is inserted so as to be relatively movable. For this reason, both valve bodies 64 and 73 can be disposed close to one side of the plungers 82 and 83, and the control valve 50 including the two valve mechanisms 60 and 70 is enlarged in the axial direction. Can be suppressed.
[0043]
In the control valve 50 of this embodiment, the solenoid mechanism 80 is provided in a state of being offset from one end of the valve housing 51. Therefore, when the control valve 50 is incorporated in the rear housing 4 of the compressor as shown in FIG. The solenoid mechanism 80 is exposed outside the rear housing 4. For this reason, wiring from the outside to the coil 85 of the solenoid mechanism 80 in the exposed state is facilitated.
[0044]
The adjustment valve body 73 and the bellows (pressure-sensitive member) 76 constituting the adjustment valve mechanism 70 of the control valve 50 are configured to be able to contact and separate based on the insertion relationship between the connecting cylinder 77 and the pressure-sensitive rod 78. . For this reason, even if the suction pressure Ps increases when the power supply to the coil 85 is stopped, even if the bellows 76 is contracted and displaced, the adjusting valve body 73 is not affected by the displacement of the bellows 76, and the action of the closing spring 75. Thus, the adjustment valve hole 72 can be held at the closed position.
[0045]
The cross-sectional area S1 of the open / close rod 65 that connects the open / close valve body 64 and the open / close plunger 82 and the opening area S2 of the open / close valve hole 63 that connects the discharge chamber 22 and the crank chamber 5 are substantially equal. However, as a result of the pressure receiving areas on both sides in the movable direction of the on-off valve body 64 being substantially equal in a state where the on-off valve hole 63 is closed, the pressure acting on the on-off valve body 64 can be substantially offset. Therefore, even when the discharge pressure Pd acting on the on-off valve body 64 is greatly increased, the on-off valve body 64 can be smoothly moved without being affected by the discharge pressure Pd and the crank pressure Pc.
[0046]
○ Since the regulating valve body 73 and the pressure sensing member 76 constituting the regulating valve mechanism 70 are provided in the same regulating valve chamber / pressure sensing chamber 71 to which the suction pressure Ps reaches, the number of rooms partitioned in the control valve is conventionally increased. This reduces the labor of drilling and rod clearance management, and is advantageous in terms of manufacturing cost.
[0047]
○ In the extraction side control in which the swash plate angle is adjusted by mainly controlling the gas discharge amount from the crank chamber 5, the controllability of the swash plate angle is that the high-pressure refrigerant gas is always stably supplied to the crank chamber 5 ( This is a precondition for ensuring the variable controllability of the discharge capacity. In this regard, the variable capacity compressor shown in FIG. 1 has a communication passage 29 as an auxiliary air supply passage connecting the discharge chamber 22 and the crank chamber 5, and a fixed throttle 29 a is provided in the middle of the communication passage 29. It has been. Therefore, even when the air supply passage 28 is closed by the on-off valve mechanism 60 and the opening degree (extraction side valve opening degree) of the extraction passage 27 is adjusted by the adjustment valve mechanism 70, the communication passage 29 with the restrictor 29a is used. Thus, a predetermined amount of refrigerant gas is constantly supplied from the discharge chamber 22 to the crank chamber 5. For this reason, the crank pressure Pc is always maintained at a predetermined pressure or higher during the operation of the compressor, so that the variable controllability of the discharge capacity by the adjusting valve mechanism 70 is not impaired.
[0048]
(Another example) You may change embodiment of this invention as follows.
○ Change the internal structure of the regulating valve chamber and pressure sensing chamber 71 as shown in FIG. In FIG. 3, the pressure-sensitive rod 78 is made shorter than in the case of FIG. 2, and the closing spring 75 is arranged between the ceiling wall of the valve chamber 71 and the spring seat 73 a formed on the head of the adjustment valve body 73. It is installed. As with the control valve in FIG. 2, the pressure-sensitive rod 78 is inserted into the connecting cylinder 77 and can be contacted and separated. On the other hand, in FIG. 4, a closing spring 75 is interposed between the ceiling wall of the valve chamber 71 and the base end portion (upper end portion) of the bellows 76, and the adjustment valve body 73 is fixed to the distal end portion (lower end portion) of the bellows 76. Has been. Even if the internal structure of the regulating valve chamber / pressure sensing chamber 71 in the control valve 50 of FIG. 2 is changed as shown in FIG. 3 or FIG. 4, the same operations and effects as described above are obtained.
[0049]
The adjustment rod 74 of the adjustment valve mechanism 70 is formed in a cylindrical shape, and the opening / closing rod 65 of the opening / closing valve mechanism 60 is fitted into the adjustment rod 74 so as to be relatively movable.
○ Adopt a diaphragm as a pressure-sensitive member used in the regulating valve mechanism 70.
[0050]
○ The pressure-sensitive rod 78 and the connecting cylinder 77 in FIGS.
○ The displacement control valve 50 is applied to a clutchless type variable displacement compressor (a compressor that directly transmits power from an external drive source to the drive shaft 6 without interposing a clutch mechanism such as an electromagnetic clutch). To do.
[0051]
(Supplementary note) A variable displacement compressor in which the control valve according to any one of claims 1 to 5 is incorporated, wherein the control valve is disposed between a discharge pressure region of the compressor and a crank chamber. The variable capacity compressor is provided with an auxiliary air supply passage 29 with a fixed throttle 29a in addition to the air supply passage 28 in which the open / close valve mechanism 60 is interposed. According to this configuration, even when the supply passage is closed by the on-off valve mechanism, a predetermined amount of refrigerant gas is supplied from the discharge pressure region to the crank chamber via the auxiliary supply passage, so that the discharge capacity can be changed. Controllability is not impaired.
[0052]
【The invention's effect】
As described above in detail, the control valve of the present invention can be applied to a general variable displacement compressor that does not include a shutoff body, and is simpler in structure and easier to manufacture than the conventional control valve. It also has an excellent effect of being advantageous.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a variable displacement compressor according to an embodiment.
FIG. 2 is a cross-sectional view of a capacity control valve.
FIG. 3 is a partial cross-sectional view showing another example of the capacity control valve.
FIG. 4 is a partial cross-sectional view showing another example of the capacity control valve.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 5 ... Crank chamber, 12 ... Swash plate, 21 ... Suction chamber (suction pressure area), 22 ... Discharge chamber (discharge pressure area), 27 ... Extraction passage, 28 ... Supply passage, 40 ... Electromagnetic clutch, 50 ... Control valve 51 ... Valve housing, 60 ... Open / close valve mechanism, 63 ... Open / close valve hole, 64 ... Open / close valve body, 65 ... Open / close rod, 66 ... Open spring, 70 ... Adjust valve mechanism, 71 ... Adjust valve chamber and pressure sensing chamber ( 72 ... adjusting valve hole, 73 ... adjusting valve body, 74 ... adjusting rod, 75 ... closing spring, 76 ... bellows (pressure sensitive member), 80 ... solenoid mechanism, 82 ... opening / closing plunger ( First plunger), 83 Adjusting plunger (second plunger), 85 Coil, E Engine engine (external drive source), S1 Rod cross-sectional area, S2 Opening area of valve hole

Claims

A control valve used in a variable displacement compressor capable of adjusting the discharge capacity by changing the inclination angle of the swash plate based on the internal pressure control of the crank chamber,
In the valve housing of the control valve, an open / close valve mechanism for controlling opening / closing of an air supply passage that communicates the discharge pressure region of the compressor and the crank chamber, and a bleed air that communicates the suction pressure region of the compressor and the crank chamber An adjustment valve mechanism for arbitrarily adjusting the opening of the passage is incorporated so as to be independently operable,
The on-off valve mechanism includes an on-off valve hole that constitutes a part of the air supply passage, an on-off valve body that opens and closes the valve hole, and an open spring that biases the valve body in a direction away from the on-off valve hole. And a first plunger connected to the on-off valve body for electromagnetically biasing the valve body in a direction to close the on-off valve hole regardless of the biasing action of the open spring,
The adjustment valve mechanism urges the valve body in a direction approaching the adjustment valve hole, an adjustment valve hole that constitutes a part of the extraction passage, an adjustment valve body that adjusts an opening degree of the valve hole, and the valve body. A closing spring, a pressure-sensitive member capable of pressing the adjustment valve body in a direction approaching the adjustment valve hole in accordance with a suction pressure, and the valve body connected to the adjustment valve body to be separated from the adjustment valve hole A second plunger for electromagnetically energizing in the direction,
The adjusting valve body and the pressure-sensitive member constituting the adjusting valve mechanism are disposed in the same chamber where the suction pressure reaches, and one coil is disposed for the first and second plungers. A control valve for a variable displacement compressor, wherein the on-off valve body and the regulating valve body are electromagnetically energized simultaneously by energization.

The on-off valve body of the on-off valve mechanism and the first plunger are connected by a rod, the adjustment valve body of the adjustment valve mechanism and the second plunger are connected by another rod, and one of the two rods is connected. 2. The control valve for a variable displacement compressor according to claim 1, wherein the control valve is formed in a cylindrical shape, and the other rod is inserted into the one rod so as to be relatively movable.

The control valve for a variable displacement compressor according to claim 1 or 2, wherein the adjustment valve body of the adjustment valve mechanism and the pressure-sensitive member are connected so as to be able to contact and separate.

One end of the on-off valve hole of the on-off valve mechanism is connected to the discharge pressure region and the other end is communicated to the crank chamber, and the cross-sectional area of the rod connecting the on-off valve body and the first plunger is approximately equal to the opening area of the on-off valve hole. The control valve for a variable displacement compressor according to any one of claims 1 to 3, wherein the control valves are equal.

The variable capacity compressor includes a clutch for selectively transmitting power from an external drive source to the compressor. Control valve for variable capacity compressor.