JP3578569B2 - Solenoid valve - Google Patents

Description

表１からソレノイドバルブ１のつりあい式を算出する。
【００８７】
【数４】
Ｆ_Ｓ −Ｆ_１ ＋Ｆ_２ −Ｆ_Ｂ ＋（Ａ_ｂ２−Ａ_Ｒ１）Ｐ_１ ＋（Ａ_Ｒ３−Ａ_ｂ２＋Ａ_Ｒ１）Ｐ_２ ＋（Ａ_Ｂ −Ａ_Ｒ３）Ｐ_３ ＝０
Ｐ_２ とＰ_３ は外部でオリフィス３６でつながっているため、Ｐ_２ ≧Ｐ_３ となるため、その差をβとして、Ｐ_２ ＝Ｐ_３ ＋βとおくと、上記数式４は下記数式５となり、そして数式６となる。
【００８８】
【数５】
Ｆ_Ｓ −Ｆ_１ ＋Ｆ_２ −Ｆ_Ｂ ＋（Ａ_ｂ２−Ａ_Ｒ１）Ｐ_１ ＋（Ａ_Ｂ −Ａ_ｂ２＋Ａ_Ｒ１）Ｐ_３ ＋（Ａ_Ｂ −Ａ_Ｂ２＋Ａ_Ｒ１）β＝０
【００８９】
【数６】
Ｐ_３ ＝｛−Ｆ_Ｓ ＋Ｆ_ＳＰ −（Ａ_ｂ２−Ａ_Ｒ１）Ｐ_１ ＋（Ａ_Ｒ３−Ａ_ｂ２＋Ａ_Ｒ１ ）β｝／（Ａ_Ｂ −Ａ_ｂ２＋Ａ_Ｒ１）
但し、Ｆ_ＳＰ＝Ｆ_１ −Ｆ_２ ＋Ｆ_Ｂ とする。
【００９０】
閉弁した瞬間すなわちバルブ閉弁状態で弁体１６と弁座１９との間に押付力が発生しない状態では、Ｐ_２ とＰ_３ が外部制御部中でオリフィス３６によりつながっているため、β＝０、ｘ＝０となり、数式６は数式７となる。
【００９１】
【数７】
Ｐ_３ ＝｛−Ｆ_Ｓ ＋Ｆ_ＳＰ−（Ａ_ｂ２−Ａ_Ｒ１）Ｐ_１ ｝／（Ａ_Ｂ −Ａ_ｂ２＋Ａ_Ｒ１）
そして、γ＝Ａ_ｂ２−Ａ_Ｒ１とおくと、下記の数式８となる。
【００９２】
【数８】
Ｐ_３ ＝（−Ｆ_Ｓ ＋Ｆ_ＳＰ−γＰ_１ ）／（Ａ_Ｂ −γ）
さらに、Ａ_ｂ２（弁体１６の小径部１６Ａ（シール部）断面積）＝Ａ_Ｒ１（ロッドＡ６の断面積）とする。すなわち、γ＝０とおくと、下記の数式９となる。尚、Ａ_ｂ２（弁体１６の小径部１６Ａ（シール部）断面積）でなく、実際は流路２０の径（シール径）内の面積で、またＡ_Ｒ１（ロッドＡ６の断面積）でなく、実際はセンタポスト５の貫通孔５２の径内の面積である。
【００９３】
【数９】
Ｐ_３ ＝（−Ｆ_Ｓ ＋Ｆ_ＳＰ）／Ａ_Ｂ （ｘ＝０）
尚、Ｆ_ＳＰとＡ_Ｂ は一定とする。
【００９４】
これより、バルブ閉弁状態で弁体１６と弁座１９との間に押付力が発生しない状態では、Ｆ_Ｓ （ソレノイド２の吸引力）によって、つまりソレノイド２の推力によってＰ_３ の圧力が決まる。
【００９５】
そして、ベローズ組立体３０を設けているため、上記数式９のＰ_３ よりベローズ組立体３０の周囲の圧力となるＰ_３ が低いと上記したベローズ組立体３０の基本作用によりベローズ部２７が長くなる（伸びる）。これにより、ベローズ部２７のロッドホルダ２９に摺接して設けられるロッドＢ２８が押され、そのロッドＢ２８にて弁体１６の凸部１６ＥがスプリングＡ２１のスプリング力に抗して押されて流路２０が開く。すなわち、力のつりあい式である数式９に基づき一定のストロークで流路２０を開ける。
【００９６】
Ｐ_２ はこのときのＰ_１ とバルブ開のストロークによって決まる。
【００９７】
一方、Ｐ_３ の圧力が高いと上記したベローズ組立体３０の基本作用によりベローズ部２７が短くなる（縮む）。これにより、ベローズ部２７のロッドホルダ２９に摺接して設けられるロッドＢ２８が押されることがないため、弁体１６がスプリングＡ２１のスプリング力にて押されて流路２０が閉じる。これにより、Ｐ_２ ＝Ｐ_３ となる。
【００９８】
上記構成のソレノイドバルブにあっては、ソレノイド本体３に通電時、プランジャ４がセンタポスト５に磁気吸引され、その推力により、プランジャ４に作動連結され、センタポスト５の貫通孔５２に摺動自在に挿入されているロッドＡ６と一体となっている弁体１６が弁座１９側に移動し、弁体１６が弁座１９に接して弁座１９に開口する流路２０を閉じてシールする。
【００９９】
このとき、ロッドＡ６を受けているセンタポスト５の貫通孔５２と流路２０とが図２に示すように軸ずれを生じていても、弁体１６の平面部１６Ｄと平面の弁座１９とが接することから、その接する部位に変化が生じないため、閉弁時確実にシールすることができる。すなわち、シール性の向上を図ることができる。
【０１００】
また、上記構成におけるソレノイドバルブの力のつりあいから、弁体１６にＰ_２ による差圧の影響を受けることがなく、Ｐ_３ の圧力に応じて伸縮するベローズ組立体３０を設けているため、それに伴ってベローズ組立体３０にロッドホルダ２９を介して作動連結されているロッドＢ２８が移動して弁座１９から弁体１６を接離して、Ｐ_３ を一定にするという自動調圧がなされる。
【０１０１】
このときも、ロッドＡ６を受けているセンタポスト５の貫通孔５２と流路２０とが図２に示すように軸ずれを生じていても、弁体１６の平面部１６Ｄと平面の弁座１９とが接することから、その接する部位に変化が生じないため、閉弁時確実にシールされ、自動調圧も精度良くなされる。すなわち、シール性の向上を図ると共に、制御性能の向上を図ることができる。
【０１０２】
また、弁体１６の平面部１６Ｄに流路２０内に入り込む凸部１６Ｅを流路２０側に向って縮径となるテーパ状としていることから、そのテーパに沿って流体が流れるため、弁体１６が弁座１９から離間して流路２０の開きはじめの急な流量（圧力）の変化を防止することができる。これにより、より制御性能の向上を図ることができる。
【０１０３】
尚、上記実施の形態では弁体が高圧側から低圧側へ差圧により変位しない構造のものを例にとって説明したが、特にこれに限るものではなく、弁体が弁座に接離して弁座に開口する流路を開閉するその他の開閉弁でも同様に適用することができる。
【０１０４】
以下、アジャストスクリュー２６の凹部２６Ａの詳細な構成について説明する。
【０１０５】
通常は、図１に示すように、ベローズ組立体３０は、蛇腹３１の端部がストレート部の内周面に略平行となり、突出部２７Ａがテーパー部に収納されるように、凹部２６Ａに取り付けられている。
【０１０６】
ベローズ組立体３０が外部圧により縮み、振動等により図３に示すように取付位置からずれたときの最大のずれはほぼ（φＤ_Ｇ −φＤ_Ｂ３）／２となる。（図４参照）これより両側のずれを考慮し、本実施形態では、最大のずれが生じて蛇腹３１がストレート部２６ａの内周面に当接する場合でも、突出部２７Ａがテーパー部２６Ｂの内周面に乗り上げて当接するようにφＤ_Ｔ２の寸法を（φＤ_Ｂ２＋φＤ_Ｇ −φＤ_Ｂ３）以上としている。従って、ベローズ組立体３０が上述の取り付け位置からずれた場合でも、外部圧が低圧となりベローズ組立体３０が再び伸びていく過程では、蛇腹３１はストレート部２６ａの内周面に規制されるとともに、ベローズ部の突出部２７Ａがテーパー部２６ｂの内周面に乗り上げているため、ベローズ組立体３０が伸びるにつれて、突出部２７Ａはテーパー部２６ｂの内周面を上って行き、ずれが修正される。さらにφＤ_Ｔ１をφＤ_Ｂ１以上とすることにより、ベローズ部の底面２７Ｂとアジャストスクリュー凹部の底面２６Ｂとが重なり、自動的に位置修正を終える。
【０１０７】
つまり、下記数式１０及び１１を満たす寸法関係を有する適度なガイド部２６ａ及びテーパー部２６ｂを設けることにより、ベローズ組立体３０はテーパー部内周面に沿って傾きを修正していくため、かみ込みによるロック現象を回避でき、バルブ開閉機能も失われない。
【０１０８】
【数１０】
φＤ_Ｔ１≧φＤ_Ｂ１
【０１０９】
【数１１】
φＤ_Ｔ２≧φＤ_Ｂ２＋φＤ_Ｇ −φＤ_Ｂ３
【０１１０】
【発明の効果】
以上説明したように、本出願に係る第１の発明によれば、ソレノイド本体に通電時、可動部材が固定部材に磁気吸引され、その推力により、可動部材に作動連結され、固定部材の貫通孔に摺動自在に挿入されている第１のロッドと一体となっている弁体が弁座側に移動し、弁体が弁座に接して弁座に開口する流路を閉じてシールされる。
【０１１１】
このとき、第１のロッドを受けている固定部材の貫通孔と流路とが軸ずれを生じていても、弁体と弁座との接離する部位を平面としていることから、接離する部位に変化が生じないため、閉弁時確実にシールされる。すなわち、シール性の向上を図ることができる。
【０１１２】
また、本出願に係る第２の発明によれば、弁体の平面部に流路内に入り込む凸部を流路側に向って縮径となるテーパ状とすることで、そのテーパに沿って流体が流れるので、弁体が弁座から離間して流路の開きはじめの急な流量（圧力）の変化を防止することができる。これにより、制御性能の向上を図ることができる。
【０１１３】
そして、本出願に係る第３の発明によれば、ソレノイドバルブの力のつりあいから、弁体が第２のポートにおける圧力による差圧の影響を受けることがなく、第３のポートに対する圧力に応じて伸縮するベローズ組立体を設けているので、それに伴ってベローズ組立体に作動連結されている第２のロッドが移動して弁座から弁体を接離して、第３のポートに対する圧力を一定にするという自動調圧がなされる。
【０１１４】
このときも、第１のロッドを受けている固定部材の貫通孔と流路とが軸ずれを生じていても、弁体と弁座との接離する部位を平面としていることから、接離する部位に変化が生じないため、閉弁時確実にシールされ、自動調圧も精度良くなされる。すなわち、シール性の向上を図ると共に、制御性能の向上を図ることができる。
【０１１５】
また、本出願に係る第４の発明によれば、上記第３の発明における弁体の平面部に流路内に入り込む凸部を流路側に向って縮径となるテーパ状としていることから、そのテーパに沿って流体が流れるため、弁体が弁座から離間して流路の開きはじめの急な流量（圧力）の変化を防止することができる。これにより、より制御性能の向上を図ることができる。
【０１１６】
また、本出願に係る第５の発明によれば、外部圧が高圧となってベローズ組立体が振動等により取り付け位置からずれた場合でも、蛇腹がガイド部内周面で規制され、ベローズ組立体が突出部を縮径となるテーパー部内周面に沿わせながら伸長するので、取り付け位置からのずれが修正され、かみ込みによるロック現象を回避でき、バルブ開閉機能も失われない。すなわち、バルブの信頼性を向上させることができる。
【図面の簡単な説明】
【図１】図１は本発明の一実施の形態に係るソレノイドバルブの全体縦断面図である。
【図２】図２は図１のＥ部拡大図で、センタポストの貫通孔と流路との軸ずれを示している。
【図３】図３は本発明の一実施の形態に係るソレノイドバルブのベローズ組立体周辺の拡大図である。
【図４】図４は本発明の一実施の形態に係るソレノイドバルブのベローズ組立体及びアジャストスクリューの寸法を示す図である。
【図５】図５は従来のソレノイドバルブの全体縦断面図である。
【図６】図６は図５のＤ部拡大図で、センタポストの貫通孔と流路との軸ずれを示している。
【図７】図７は従来のソレノイドバルブにおけるベローズ組立体のロック現象を示す図である。
【符号の説明】
１ ソレノイドバルブ
２ ソレノイド
２Ａ 弁本体
３ ソレノイド本体
４ プランジャ（可動部材）
４１ 凹部
４２ スプリングＢ（第２の付勢手段）
５ センタポスト（固定部材）
５１ 外向きフランジ部
５２ 貫通孔
５３ 通路
５４ 凹部
６ ロッドＡ（第１のロッド）
７ ケース
７１ 内向きフランジ部
７２ 段差面
８ 中空部
９ ボビン
１０ コイル
１１ スペーサ
１１Ａ 凸部
１２ アッパープレート
１２Ａ 外向きフランジ部
１２Ｂ 筒状部
１３ ブラケット
１４ ソレノイド本体中空部
１５ 軸受
１６ 弁体
１６Ａ 小径部
１６Ｂ 中径部
１６Ｃ 大径部
１６Ｄ 平面部
１６Ｅ 凸部
１７ 弁室
１８ バルブボディ
１８Ａ 凹部
１８Ｂ 孔
１８Ｃ 収納部
１９ 弁座
２０ 流路
２１ スプリングＡ（第１の付勢手段）
２２ 流入ポート（第１のポート）
２２Ａ フィルター
２３ 制御ポート（第２のポート）
２４ 連通路
２５ カバー
２６ アジャストスクリュー
２６Ａ 凹部
２６Ｂ 凹部底面
２６ａ ストレート部
２６ｂ テーパー部
２６ｃ 段部
２７ ベローズ部
２７Ａ 突出部
２７Ｂ 突出部端面
２８ ロッドＢ（第２のロッド）
２８Ａ 大径部
２８Ｂ 小径部
２９ ロッドホルダ
３０ ベローズ組立体
３１ 蛇腹
３２ ピンＡ
３２Ａ 凹部
３３ スプリングＣ（第３の付勢手段）
３４ ピンＢ
３５ 吸入ポート（第３のポート）
３６ オリフィス[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a solenoid valve used for controlling, for example, various oils, pneumatic devices, and the like, and also relates to a solenoid valve whose valve body is not displaced from a high pressure side to a low pressure side by a differential pressure.
[0002]
[Prior art]
As a conventional solenoid valve of this type, for example, there is one shown in FIG.
[0003]
That is, the solenoid valve 100 includes a solenoid 101 and a valve body 101A integrally provided.
[0004]
The solenoid 101 has a hollow solenoid body 102, a plunger 103 as a movable member made of a magnetic material inserted reciprocally into the hollow interior of the solenoid body 102, and is provided coaxially opposite the plunger 103. A center post 104 serving as a fixing member made of a magnetic material, and a rod serving as a first rod operatively connected to the plunger 103 and slidably inserted into a through hole 105 formed through the center post 104 in the axial direction. A106. The clearance between the rod A106 and the through hole 105 is sealed.
[0005]
The valve body 101A includes a valve body 107 having a steel ball 108 at the tip, a valve body 110 forming a recess 104A of the center post 104 into which the valve body 107 is reciprocally inserted, and a valve chamber 109; The valve seat 111 provided in the chamber 109 is provided with a valve seat 111 to be brought into contact with and separated from the steel ball 108, and a flow path 112 opened to the valve seat 111 and communicating with the valve chamber 109.
[0006]
In the valve chamber 109, a spring A117 is provided as first urging means for urging the valve body 107 in a direction away from the valve seat 111.
[0007]
Further, the valve element 107 is integrated with a rod A106 which is operatively connected by being brought into contact with the plunger 103 of the solenoid 101 by the spring force of a spring B103A as a second urging means. The plunger 103 is urged away from the center post 104 by the spring force of the spring A117.
[0008]
On the side wall of the valve body 110, an inflow port 113 as a first port for communicating the outside with the valve chamber 109, a control port 114 as a second port for communicating the outside with the flow path 112, A communication passage 116 is provided for communicating between the control port 114 and the plunger 103 of the solenoid 101 and the center post 104 via a passage 115 formed in the center post 104 and formed in the axial direction.
[0009]
One end of a cover 118 having both ends opened at the distal end of the valve body 110 is attached to the valve body 101A, and the bellows assembly 119 is housed in the cover 118. An adjust screw 120 having a recess 120A into which the end 119A of the bellows assembly 119 is fitted is attached to the other open end of the cover 118 and closed.
[0010]
The bellows assembly 119 includes a rod B122 as a second rod operatively connected to the bellows portion 121 and extending toward the steel ball 108 of the valve body 107 of the solenoid 101. The rod B122 is stepped and includes a large-diameter portion 122A and a small-diameter portion 122B.
[0011]
On the other hand, the valve body 110 has a hole 110A communicating with the inside of the cover 118 coaxially with the flow path 112, and the large-diameter portion 122A of the rod B122 is slidably inserted into the hole 110A, and has a small diameter. The portion 122B faces the inside of the flow channel 112, and the tip thereof contacts the steel ball 108. This rod B122 is clearance-sealed by the large diameter portion 122A and the hole 110A.
[0012]
The bellows portion 121 of the bellows assembly 119 includes a bellows 121A having a sealed structure and a vacuum inside, and a spring C121B as a third biasing unit for biasing the bellows 121A inside the bellows 121A in a direction of extending the bellows 121A. And expands and contracts in response to changes in external fluid pressure.
[0013]
Further, the cover 118 has a suction port 123 as a third port for communicating the outside and the inside of the cover 118.
[0014]
Next, the operation of the solenoid valve 100 having the above configuration will be described.
[0015]
First, when the solenoid 101 is turned off, the valve body 107 (steel ball 108) is separated from the valve seat 111 by the spring force of the spring A117, and the flow path 112 opened to the valve seat 111 is opened. As a result, the inflow port 113 and the control port 114 communicate with each other via the valve chamber 109, and the discharge pressure P from the inflow port 113, for example, from an external control unit (not shown).₁  Is the control pressure P via the control port 114.₂  Is output to the external control unit. That is, the control pressure P₂  = P₁  It becomes.
[0016]
Next, when the solenoid 101 is turned on, the plunger 103 is magnetically attracted to the center post 104, and the thrust of the plunger 103 causes the valve body 107 (steel ball 108) integrated with the rod A 106 operatively connected to the plunger 103 to spring. The steel ball 108 moves toward the valve seat 111 against the spring force of A117, and the steel ball 108 closes the flow path 112 opened to the valve seat 111.
[0017]
At this time, the suction pressure P of the external control unit from the suction port 123 according to the thrust by the current applied to the solenoid 101₃  Control pressure P₂  Control.
[0018]
Control pressure P₂  Is also supplied between the center post 104 and the plunger 103 through a communication passage 116 provided in the valve body 110 and a passage 115 of the center post 104.
[0019]
In addition, since the diameter of the flow path 112 which forms a seal diameter at which the steel ball 108 is in contact with and seals the valve seat 111 is substantially the same as the diameter of the through hole 105 into which the rod A 106 of the center post 104 is inserted, The valve element 107 (steel ball 108) integrated with the rod A106 is not affected by the pressure difference.
[0020]
From these, when the channel 112 is closed by the steel ball 108 with a certain thrust, the suction pressure P to the suction port 123 is increased.₃  So that the bellows assembly 119 becomes an external gas or liquid pressure so as to balance the pressure at a certain constant pressure.₃  The steel ball 108 comes into contact with and separates from the valve seat 111 via the small-diameter portion 122B of the rod B122 operatively connected to the bellows portion 121 to change the suction pressure P.₃  Is automatically regulated.
[0021]
[Problems to be solved by the invention]
By the way, in the case of the above-mentioned prior art, since the valve element 107 and the rod A106 are integrated, they are not affected by the differential pressure (the sealing area by the steel ball 108 × P₂  = Cross-sectional area of rod A106 x P₂  Therefore, the valve element 107 does not receive the pressure difference. Therefore, when the axial deviation occurs between the through hole 105 of the center post 104 receiving the rod A 106 and the flow path 112 (the seal portion), Since the distal end portion is formed of a steel ball 108, a clearance (arrow F in the figure) opens as shown in FIG.
[0022]
Further, in the case of the above-described conventional technology, the end 119A of the bellows assembly is fitted into the recess 120A of the adjustment screw. However, when the outside of the bellows assembly 119 becomes high pressure and the bellows length becomes short, vibration or the like causes As shown in FIG. 7, the bellows assembly was tilted and disengaged from the recess 120A, and a locking phenomenon due to biting occurred. As a result, the outside of the bellows assembly becomes low pressure, so that the bellows cannot be extended even if it tries to extend, and the opening and closing function of the valve has been lost.
[0023]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the related art, and an object of the present invention is to provide a solenoid valve capable of improving sealing performance and valve reliability.
[0024]
[Means for Solving the Problems]
In order to achieve the above object, in the first invention according to the present application, a solenoid body having a hollow inside, a movable member made of a magnetic material reciprocally inserted into the hollow inside of the solenoid body, A fixed member made of a magnetic material provided coaxially with the movable member, a through hole formed through the fixed member in an axial direction, and the movable member slidably inserted into the through hole. A valve operatively connected to the valve, a valve body provided integrally with the rod, a valve seat to which the valve body comes and goes, and a flow path opening to the valve seat; The portion where the and the valve seat come and go is made flat.
[0025]
In order to achieve the above object, in the second invention according to the present application, the flat portion of the valve body enters the flow path into the flat portion of the portion where the portion where the valve body comes into contact with and separates from the valve seat is a flat surface. It is characterized in that a convex portion is provided, and the convex portion has a tapered shape whose diameter decreases toward the flow channel side.
[0026]
In order to achieve the above object, according to a third aspect of the present invention, there is provided a solenoid body having a hollow interior, a movable member made of a magnetic material reciprocally inserted into the hollow interior of the solenoid body, A fixed member made of a magnetic material provided coaxially with the movable member, a through hole formed through the fixed member in an axial direction, and a first member slidably inserted into the through hole. A rod, a valve body provided integrally with the first rod and reciprocally inserted into a valve chamber provided in a valve body, and a valve seat provided in the valve chamber to which the valve body comes in contact with and separates from the valve body. A flow path opening to the valve seat, a first urging means for urging the valve body in a direction away from the valve seat, and a second urging means for bringing the movable member into contact with the first rod. A second urging means for urging the rod side, a bellows having a sealed structure and a vacuum inside, and a method for extending the bellows A bellows assembly having third biasing means for biasing the valve body, a second rod operatively connected to the bellows assembly, and the valve body, wherein a first body for communicating the outside with the valve chamber is provided. A second port that communicates the flow path with the outside, a communication path that communicates between the movable member and the fixed member via the second port and the outside, and the bellows assembly includes A storage portion to be stored, a third port communicating between the outside and the inside of the storage portion, a hole provided coaxially with the flow path and slidably inserted with the second rod, Wherein the second rod extends toward the valve body through the flow path, and has a diameter of the through hole and a diameter of the flow path substantially equal to each other. Is characterized in that a portion where the contact and separation are made flat.
[0027]
In order to achieve the above object, in the fourth invention according to the present application, the valve body and the valve seat come into contact with and separate from each other into a flat portion of the valve body and enter the flow path. It is characterized in that a convex portion is provided, and the convex portion has a tapered shape whose diameter decreases toward the flow channel side.
[0028]
In order to achieve the above object, according to a fifth aspect of the present invention, an end of the bellows assembly opposite to a side to which the second rod is connected is provided with an extension and contraction of the bellows assembly. A stepped projection having a diameter smaller than that of the bellows, the projection having a diameter smaller than that of the bellows, and an outer shape of an end of the bellows assembly for mounting the bellows assembly on a surface of the storage portion facing the end. A concave portion provided on the opening side of the concave portion, the guide portion having an inner peripheral surface substantially parallel to the direction of expansion and contraction of the bellows assembly, and a step portion provided on the guide portion. And a tapered portion having a diameter smaller than the guide portion and reduced in diameter toward the bottom surface of the concave portion, and the bellows assembly displaced from a mounting position of the concave portion is provided with the bellows of the guide portion. When extending while being restricted by the inner peripheral surface, the protrusion Characterized by modifying the deviation from the mounting position of the recess by rides on the inner peripheral surface of the tapered portion.
[0029]
In the solenoid valve having the configuration according to the first aspect of the invention, when the solenoid body is energized, the movable member is magnetically attracted to the fixed member, is operatively connected to the movable member by its thrust, and slides into the through hole of the fixed member. The valve body integrated with the movably inserted rod moves to the valve seat side, and the valve body comes into contact with the valve seat to close the flow path opened to the valve seat.
[0030]
At this time, even if the through hole of the fixing member receiving the rod and the flow path are misaligned, since the part where the valve body and the valve seat come and go is a plane, it changes to the part that comes into contact and separates. Does not occur, so the valve is securely sealed when the valve is closed.
[0031]
Further, in the configuration according to the second aspect of the invention, since the convex portion that enters the flow channel in the flat portion of the valve body has a tapered shape whose diameter decreases toward the flow channel side, the fluid flows along the taper. Therefore, it is possible to prevent a sudden change in the flow rate (pressure) when the valve element is separated from the valve seat and the flow path starts to open.
[0032]
In the solenoid valve having the configuration according to the third aspect, the diameter of the through hole of the fixing member for receiving the first rod and the diameter of the flow path are substantially the same, and the flow path and the external And a communication path for communicating between the movable member and the fixed member, and the second rod is connected to the first rod and the valve body integral with the first rod from the balance of the force of the solenoid valve. It is not affected by the pressure difference due to the pressure at the port 2.
[0033]
Further, since the bellows assembly is provided in the storage portion having the third port of the valve body, the bellows assembly expands and contracts in accordance with the pressure applied to the third port, and accordingly, is operatively connected to the bellows assembly. As described above, the second rod moves and the valve element does not receive the differential pressure as described above, so that the valve element can be brought into contact with or separated from the valve seat, and the automatic pressure adjustment to keep the pressure on the third port constant. Done.
[0034]
Also at this time, even if the through hole of the fixing member receiving the first rod integrated with the valve body and the flow path are misaligned, the portion where the valve body and the valve seat come and go is a plane. Therefore, since there is no change in the contacting / separating portion, the sealing is reliably performed when the valve is closed, and the automatic pressure regulation is performed with high accuracy.
[0035]
In the configuration according to the fourth aspect of the present invention, the convex portion that enters the flow path in the flat portion of the valve element according to the third aspect of the invention has a tapered shape whose diameter decreases toward the flow path side. Since the fluid flows along the flow path, it is possible to prevent a sudden change in the flow rate (pressure) when the valve element is separated from the valve seat and the flow path starts to open.
[0036]
Further, in the configuration according to the fifth aspect of the invention, even when the bellows assembly is displaced from a mounting position due to vibration or the like when the external pressure becomes high and contracts due to vibration, the bellows assembly moves the bellows to the inner peripheral surface of the guide portion. When it is restricted and extended, the protruding part rides on the inner peripheral surface of the tapered part, so it is guided to the inner peripheral surface of the tapered part that becomes smaller in diameter as it elongates and is returned to the mounting position, The locking phenomenon can be avoided, and the valve opening / closing function is not lost.
[0037]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described based on the illustrated embodiments. In FIG. 1 showing a solenoid valve according to an embodiment of the present invention, reference numeral 1 denotes an entire solenoid valve, and the solenoid valve 1 is formed by integrally providing a solenoid 2 with a valve body 2A.
[0038]
The solenoid 2 has a hollow solenoid main body 3, a plunger 4 as a movable member made of a magnetic material inserted reciprocally into the hollow interior of the solenoid main body 3, and is provided coaxially opposite the plunger 4. A center post 5 as a fixing member made of a magnetic material and a rod A6 as a first rod operatively connected to the plunger 4 are provided.
[0039]
The solenoid body 3 includes a case 7 having both ends open, a coil 10 wound around a bobbin 9 having a hollow portion 8 formed through in the axial direction and housed in the case 7, and a spacer 11 forming a magnetic path. And an upper plate 12.
[0040]
One open end of the case 7 has an inward flange 71 extending radially inward, and has an inner diameter larger than the diameter of the hollow portion 8 of the bobbin 9. An annular spacer 11 is provided on the inner peripheral surface of the inward flange portion 71 via a bracket 13 in a fluid-tight manner via a bracket 13, and holds the bobbin 9 around which the coil 10 is wound.
[0041]
The spacer 11 has a convex portion 11A protruding radially inward in the axially intermediate portion of the inner peripheral surface thereof, and the inner diameter of the convex portion 11A on the bobbin 9 side is equal to the diameter of the hollow portion 8 of the bobbin 9. Is almost the same as
[0042]
The upper plate 12 is a tubular member having an outward flange portion 12A extending radially outward. The end surface of the cylindrical portion 12B is in contact with the end surface of the bobbin 9, and the outer peripheral surface of the outward flange portion 12A is provided in contact with the step surface 72 at the opening end of the case 7, and the tip of the step surface 72 is provided. The upper plate 12 is fixed by caulking at the portion.
[0043]
Further, since the inner diameter of the cylindrical portion 12B of the upper plate 12 is substantially the same as the diameter of the hollow portion 8 of the bobbin 9, the inner diameter portion of the cylindrical portion 12B, the hollow portion 8 of the bobbin 9, The hollow portion 14 of the solenoid body 3 of the solenoid body 3 is formed by the inner diameter of the protrusion 11A of the spacer 11 on the bobbin 9 side.
[0044]
In the hollow portion 14 of the solenoid main body, there is provided a bearing 15 having a substantially U-shaped cross section which is provided over the entire length thereof and closes an opening end on the upper plate 12 side. The plunger 4 is inserted through the bearing 15 so as to be able to reciprocate in the solenoid body hollow portion 14 toward the closed portion side.
[0045]
A center post 5 is inserted and fixed coaxially with the plunger 4 into a hollow portion 14 of the solenoid main body via a bearing 15 coaxially. The end of the center post 5 on the valve body 2A side has an outward flange portion 51 extending radially outward. The outward flange portion 51 includes the convex portion 11A of the spacer 11 and the convex portion 11A. The center post 5 is positioned in contact with the stepped portion of the inner peripheral surface of the valve body 2A.
[0046]
The center post 5 has a through-hole 52 formed through the center axis, and one end of the rod A6 extends through the through-hole 52 toward the plunger 4 and the other end toward the valve body 16 described later. It is slidably inserted. The through hole 52 and the rod A6 are sealed with a clearance.
[0047]
On the other hand, the plunger 4 has a concave portion 41 that opens to the closed portion side of the bearing 15, and a spring B42 as a second urging means is provided in the concave portion 41. One end of the spring B42 is in contact with the end surface of the closed portion of the bearing 15, and the other end is in contact with the bottom surface of the concave portion 41 to urge the plunger 4 toward the rod A6.
[0048]
The end face of the plunger 4 comes into contact with the end face of the rod A6 by the spring force of the spring B42, and the rod A6 is operatively connected to the plunger 4 by this contact.
[0049]
Further, a passage 53 is formed in the outer periphery of the center post 5 so as to penetrate in the axial direction.
[0050]
The valve body 2A includes a valve body 18 that forms the valve chamber 17 with the valve body 16 and the concave portion 54 of the center post 5, a valve seat 19 provided in the valve chamber 17 with which the valve body 16 comes in contact with and separates from the valve body 16, and a valve seat. 19, a flow passage 20 communicating with the valve chamber 17 and a bellows assembly 30 housed in a housing part 18C provided on the distal end side of the valve body 18.
[0051]
The valve body 18 has a concave portion 18A that opens in the axial direction for forming the valve chamber 17. The valve body 18 is coaxial with the center post 5 and the spacer 11 by using the concave portion 18A and the solenoid 2 side. It is assembled integrally on top.
[0052]
The valve body 16 is inserted into the valve chamber 17 formed by the concave portion 18A of the valve body 18 and the concave portion 54 of the center post 5 so as to be able to reciprocate, and to be able to contact and separate from the valve seat 19. The valve body 16 is stepped and includes small, medium, and large diameter portions 16A, 16B, and 16C in order from the valve seat 19 side. The rod A6 of the solenoid 2 is integrally attached to the end face of the large diameter portion 16C, so that the valve body 16 moves together with the rod A6.
[0053]
Further, a spring A21 is provided in the valve chamber 17 as first urging means for urging the valve body 16 in a direction away from the valve seat 19. One end of the spring A21 abuts the step surface between the middle diameter portion 16B and the large diameter portion 16C of the valve body 16, and the other end abuts the end surface of the valve seat 19 of the valve chamber 17 so that the valve body 16 is seated. It is urged in a direction away from 19.
[0054]
Since the valve body 16 is integrated with the rod A6 operatively connected to the plunger 4 as described above, the plunger 4 is urged in a direction away from the center post 5 by the spring force of the spring A21. ing.
[0055]
The valve seat 19 is a flat surface, and a flow path 20 is formed on the center axis of the valve body 18 so as to open in the flat surface. On the other hand, the tip of the small-diameter portion 16A of the valve body 16 that comes into contact with and separates from the valve seat 19 is also flat, and the convex portion protrudes into the flow path 20 on the central axis of the valve body 16 in the flat portion 16D. 16E. The convex portion 16E has a tapered shape whose diameter decreases toward the flow path 20 side.
[0056]
Further, on the side wall of the valve body 18, an inflow port 22 as a first port for communicating the outside with the valve chamber 19, a control port 23 as a second port for communicating the outside with the flow path 20, A communication path 24 that communicates between the control port 23, the plunger 4, and the center post 5 via a path 53 of the center post 5 is provided.
[0057]
The inflow port 22 and the control port 23 are formed to penetrate in the radial direction with respect to the side wall of the valve body 18, and a filter 22 </ b> A is attached to an outer open end of the inflow port 22. On the other hand, the communication passage 24 is formed so as to penetrate in the axial direction. One open end of the communication passage 24 is located outside the control port 23, and the other is located in the passage 53 of the center post 5.
[0058]
One end of an opening of a cover 25 that opens at both ends is attached to the tip of the valve body 18, and a storage portion 18 </ b> C is formed by the cover 25, and a bellows assembly 30 is provided in the cover 25. It is stored. An adjust screw 26 that is in contact with the bellows assembly 30 is attached to the other open end of the cover 25 to close the open end.
[0059]
The bellows assembly 30 includes a bellows portion 27, a rod holder 29 that supports a rod B28 as a second rod operatively connected to the bellows portion 27, and a third biasing force that biases the bellows portion 27 in the extending direction. And a spring C33 as a means.
[0060]
The bellows portion 27 includes a bellows 31 having a substantially bottomed cylindrical shape, a pin A32 having a substantially T-shaped cross section for closing an open end of the bellows 31, and a spring C33 inserted into the bellows 31. The bellows portion 27 has a sealed structure and the inside is vacuum.
[0061]
A pin B34 having a T-shaped cross section is provided on the closed portion side in the bellows 31 so as to face the pin A32, and the flange portion 34a of the pin B34 is fixed to the stepped protruding portion 27A of the bellows portion. ing. The protruding portion 27A has a smaller diameter than the bellows 31 and has a tapered shape in which the outer peripheral surface is reduced in diameter toward the end. A spring C33 is provided between the pin B34 and the pin A32 on the outer periphery of each projection. One end of the spring C33 is in contact with the end surface of the flange portion 34a of the pin B34, and the other end is in contact with the end surface of the flange portion of the pin A32, and urges the bellows 31 (bellows portion 27) in the extending direction.
[0062]
On the valve body 18 side of the pin A32, there is a concave portion 32A formed on the center axis of the pin A32, and in the concave portion 32A, a concave rod holder 29 is formed with an opening portion on the valve body 18 side. It is press-fitted.
[0063]
The closed side of the bellows 31 of the bellows 31 is mounted in a recess 26A of the adjusting screw 26. The recess 26A has a straight portion 26a and a step 26c having shapes substantially matching the outer shapes of the bellows 31 and the protrusion 27A. The tapered portion 26b is adjacent to the tapered portion 26b.
[0064]
The detailed configuration of the recess 26A of the adjusting screw will be described later.
[0065]
The rod B28 is inserted into the rod holder 29 of the bellows assembly 30, and the rod B28 is in sliding contact with the rod holder 29 (in a free state). The rod B28 is stepped and includes a large diameter portion 28A and a small diameter portion 28B.
[0066]
On the other hand, the valve body 18 has a hole 18B coaxially with the flow path 20 and communicating with the inside of the cover 25. The large diameter portion 28A of the rod B28 is slidably inserted into the hole 18B, The portion 28 </ b> B faces the inside of the flow path 20, and the tip thereof contacts the convex portion 16 </ b> E of the valve body 16. The rod B28 is clearance-sealed by the large diameter portion 28A and the hole 18A.
[0067]
Further, the cover 25 has a suction port 35 as a third port that communicates between the outside and the inside of the cover 25.
[0068]
Here, the basic operation of the bellows assembly 30 will be described.
[0069]
When the pressure or the liquid pressure of the gas around the bellows assembly 30 (hereinafter, gas is described as an example) is high, the compressive force of the gas becomes stronger than the urging force (repulsive force) of the spring C33. The part 27 is pushed in the axial direction and its length L is reduced.
[0070]
When the pressure of the surrounding gas decreases, the repulsive force of the spring C33 becomes larger than the compressive force of the gas, so that the bellows portion 27 expands in the axial direction, and the length L thereof increases.
[0071]
Next, the operation of the solenoid valve 1 having the above configuration will be described.
[0072]
First, when the solenoid 2 is turned off, the valve body 16 is separated from the valve seat 19 by the spring force of the spring A21, the flow path 20 opened to the valve seat 19 is opened, and the valve is opened. Thereby, the inflow port 22 and the control port 23 communicate with each other through the valve chamber 17, and the discharge pressure P from the inflow port 22 through, for example, an external control unit (not shown) through the filter 22A.₁  (Hereinafter simply P₁  The control pressure P via the control port 23.₂  (Hereinafter simply P₂  To the external control unit. That is, P₂  = P₁  It becomes.
[0073]
At this time, the plunger 4 is separated from the center post 5 via the valve body 16 and the rod A6 by the spring force of the spring A21.
[0074]
Next, when the solenoid 2 is turned on, a magnetic circuit composed of the center post 5 → the spacer 11 → the case 7 → the upper plate 12 → the plunger 4 → the center post 5 is formed, and the plunger 4 is magnetically attracted to the center post 5.
[0075]
By the thrust, the valve body 16 integral with the rod A6 abutting (operably connected) to the end face of the plunger 4 moves toward the valve seat 19 against the spring force of the spring A21, and the valve The flat portion 16D of the body 16 is in contact with the flat valve seat 19 to close the flow passage 20 to bring the valve into a valve closed state, and the flow passage 20 is sealed by the flat portion 16D.
[0076]
Thereby, the flat portion 16D of the small diameter portion 16A of the valve body 16 forms a seal portion with the valve seat 19. In addition, the tapered convex portion 16E of the flat portion 16D enters the flow path 20.
[0077]
The suction pressure P of the external control unit with respect to the suction port 35 according to the thrust by the current applied when the solenoid 2 is ON.₃  (Hereinafter simply P₃  P)₂  Control.
[0078]
P₂  Is also supplied between the plunger 4 and the center post 5 through the communication passage 24 provided in the valve body 18 and the passage 53 of the center post 5. Further, the diameter of the flow path 20 having a seal diameter in which the flat portion 16D of the valve body 16 is sealed in contact with the valve seat 19, and the diameter of the through hole 52 in which the rod A6 of the center post 5 is inserted (received). Since the diameter is almost the same, the valve element 16 integrated with the rod A6 is not affected by the pressure difference from the high pressure side to the low pressure side.
[0079]
Here, P is determined according to the thrust by the current applied to the solenoid 2 described above.₃  P so that₂  Will be described based on the following equation for balancing the force of the solenoid valve 1 having the above-described configuration.
[0080]
A_P  : Cross section of plunger 4, A_R1: Cross-sectional area of rod A6, A_b1: Cross-sectional area of large diameter portion 16C of valve body 16, A_b2: Cross-sectional area of small diameter portion 16A (sealing portion) of valve body 16, A_R2: Cross-sectional area of small diameter portion 28B of rod B28, A_R3: Cross-sectional area of large diameter portion 28A of rod B28, A_B  : Effective area of bellows 27 (bellows 31), F_S  : Attraction force of solenoid 2, F₁  : Spring force of spring A21, F₂  : Spring force of spring B42, F_B  : Defined as the force of the bellows assembly 30 (including the spring force of the spring C33).
[0081]
F₁  , F₂  , F_B  Is obtained from the following Expressions 1 to 3. Note that x indicates a displacement amount based on the valve closing position.
[0082]
(Equation 1)
F₁  = K₁  (Δ₁  -X)
In the above equation 1, k₁  : Spring constant of spring A21, δ₁  : The amount of deflection at the valve closing position.
[0083]
(Equation 2)
F₂  = K₂  (Δ₂  + X)
In the above equation 2, k₂  : Spring constant of spring B42, δ₂  : The amount of deflection at the valve closing position.
[0084]
(Equation 3)
F_B  = K_B  (Δ_B  -X)
In the above equation 3, k_B  : Spring constant in the bellows assembly 30 (both the spring constant of the bellows assembly 30 itself and the spring constant of the spring C33), δ_B  : The amount of deflection at the valve closing position.
[0085]
The following table summarizes the operating forces in the valve closing and valve opening directions.
[0086]
[Table 1]

A balancing equation for the solenoid valve 1 is calculated from Table 1.
[0087]
(Equation 4)
F_S  -F₁  + F₂  -F_B  + (A_b2-A_R1) P₁  + (A_R3-A_b2+ A_R1) P₂  + (A_B  -A_R3) P₃  = 0
P₂  And P₃  Is connected to the outside by the orifice 36, so that P₂  ≧ P₃  And the difference is β, P₂  = P₃  If + β is set, the above equation 4 becomes the following equation 5, and then becomes equation 6.
[0088]
(Equation 5)
F_S  -F₁  + F₂  -F_B  + (A_b2-A_R1) P₁  + (A_B  -A_b2+ A_R1) P₃  + (A_B  -A_B2+ A_R1) Β = 0
[0089]
(Equation 6)
P₃  = ｛-F_S  + F_SP  -(A_b2-A_R1) P₁  + (A_R3-A_b2+ A_R1  ) Β｝ / (A_B  -A_b2+ A_R1)
Where F_SP= F₁  -F₂  + F_B  And
[0090]
At the moment when the valve is closed, that is, when no pressing force is generated between the valve body 16 and the valve seat 19 in the valve closed state, P₂  And P₃  Are connected by the orifice 36 in the external control unit, β = 0 and x = 0, and Expression 6 becomes Expression 7.
[0091]
(Equation 7)
P₃  = ｛-F_S  + F_SP-(A_b2-A_R1) P₁  ｝ / (A_B  -A_b2+ A_R1)
And γ = A_b2-A_R1In other words, Equation 8 below is obtained.
[0092]
(Equation 8)
P₃  = (-F_S  + F_SP-ΓP₁  ) / (A_B  -Γ)
Furthermore, A_b2(Small-diameter portion 16A (seal portion) cross-sectional area of valve body 16) = A_R1(Cross-sectional area of rod A6). That is, if γ = 0, the following equation 9 is obtained. A_b2In fact, not the area of the small diameter portion 16A (seal portion) of the valve body 16 but the area within the diameter of the flow path 20 (seal diameter)._R1Instead of (the cross-sectional area of the rod A6), it is actually the area within the diameter of the through hole 52 of the center post 5.
[0093]
(Equation 9)
P₃  = (-F_S  + F_SP) / A_B    (X = 0)
Note that F_SPAnd A_B  Is constant.
[0094]
Accordingly, in a state in which no pressing force is generated between the valve body 16 and the valve seat 19 in the valve closed state, F_S  (Attraction force of the solenoid 2), that is, P₃  Is determined.
[0095]
Since the bellows assembly 30 is provided, P₃  P which becomes the pressure around the bellows assembly 30₃  Is low, the bellows portion 27 becomes long (extends) due to the basic operation of the bellows assembly 30 described above. As a result, the rod B28 provided in sliding contact with the rod holder 29 of the bellows part 27 is pushed, and the convex part 16E of the valve body 16 is pushed by the rod B28 against the spring force of the spring A21, so that the flow path 20 Opens. That is, the flow path 20 is opened at a constant stroke based on Expression 9 which is a balance equation of force.
[0096]
P₂  Is P at this time₁  And the stroke of valve opening.
[0097]
On the other hand, P₃  Is high, the bellows portion 27 is shortened (shrinks) due to the basic operation of the bellows assembly 30 described above. Thus, since the rod B28 provided in sliding contact with the rod holder 29 of the bellows portion 27 is not pushed, the valve body 16 is pushed by the spring force of the spring A21, and the flow path 20 is closed. This gives P₂  = P₃  It becomes.
[0098]
In the solenoid valve having the above configuration, when the solenoid body 3 is energized, the plunger 4 is magnetically attracted to the center post 5, and is operatively connected to the plunger 4 by the thrust, so that the plunger 4 can slide in the through hole 52 of the center post 5. The valve body 16 integrated with the rod A6 inserted into the valve seat moves to the valve seat 19 side, and the valve body 16 comes into contact with the valve seat 19 to close and seal the flow path 20 opened to the valve seat 19.
[0099]
At this time, even if the through hole 52 of the center post 5 receiving the rod A6 and the flow path 20 are misaligned as shown in FIG. 2, the flat portion 16D of the valve body 16 and the flat valve seat 19 are Since there is contact, no change occurs in the contacting portion, so that the valve can be reliably sealed when the valve is closed. That is, the sealing performance can be improved.
[0100]
Further, from the balance of the force of the solenoid valve in the above configuration, P₂  Is not affected by the pressure difference₃  Is provided, the rod B28 operatively connected to the bellows assembly 30 via the rod holder 29 moves to move the valve body 16 from the valve seat 19 with the bellows assembly 30. Contact and separate, P₃  Is made constant.
[0101]
At this time, even if the through hole 52 of the center post 5 receiving the rod A6 and the flow path 20 are misaligned as shown in FIG. 2, the flat portion 16D of the valve body 16 and the flat valve seat 19 Since there is no change in the contacting portion, the seal is reliably sealed when the valve is closed, and the automatic pressure adjustment is performed with high accuracy. That is, it is possible to improve the sealing performance and control performance.
[0102]
In addition, since the convex portion 16E that enters the flow path 20 into the flat portion 16D of the valve body 16 has a tapered shape whose diameter is reduced toward the flow path 20, the fluid flows along the taper. 16 can be separated from the valve seat 19 to prevent a sudden change in the flow rate (pressure) when the flow path 20 starts to open. Thereby, control performance can be further improved.
[0103]
In the above-described embodiment, the structure in which the valve body is not displaced from the high pressure side to the low pressure side by the differential pressure is described as an example. However, the present invention is not particularly limited to this. Other open / close valves that open / close a flow path that is open to the outside can be similarly applied.
[0104]
Hereinafter, the detailed configuration of the concave portion 26A of the adjusting screw 26 will be described.
[0105]
Normally, as shown in FIG. 1, the bellows assembly 30 is attached to the concave portion 26A such that the end of the bellows 31 is substantially parallel to the inner peripheral surface of the straight portion, and the projecting portion 27A is housed in the tapered portion. Has been.
[0106]
When the bellows assembly 30 shrinks due to external pressure and shifts from the mounting position as shown in FIG. 3 due to vibration or the like, the maximum shift is substantially (φD_G  -ΦD_B3) / 2. (See FIG. 4) In view of this, in the present embodiment, even when the maximum deviation occurs and the bellows 31 abuts on the inner peripheral surface of the straight portion 26a, the projecting portion 27A is formed inside the tapered portion 26B in the present embodiment. ΦD so that it rides on the periphery and touches_T2The dimensions of (φD_B2+ ΦD_G  -ΦD_B3) Or more. Therefore, even when the bellows assembly 30 is displaced from the above-described mounting position, the bellows 31 is restricted by the inner peripheral surface of the straight portion 26a in the process of reducing the external pressure and expanding the bellows assembly 30 again, Since the projection 27A of the bellows portion rides on the inner peripheral surface of the tapered portion 26b, as the bellows assembly 30 extends, the projection 27A goes up the inner peripheral surface of the tapered portion 26b, and the displacement is corrected. . Further φD_T1Is φD_B1With the above, the bottom surface 27B of the bellows portion and the bottom surface 26B of the adjusting screw recess overlap, and the position correction is automatically completed.
[0107]
That is, the bellows assembly 30 corrects the inclination along the inner peripheral surface of the tapered portion by providing an appropriate guide portion 26a and a tapered portion 26b having a dimensional relationship satisfying the following Expressions 10 and 11, so that the biting The locking phenomenon can be avoided, and the valve opening / closing function is not lost.
[0108]
(Equation 10)
φD_T1≧ φD_B1
[0109]
(Equation 11)
φD_T2≧ φD_B2+ ΦD_G  -ΦD_B3
[0110]
【The invention's effect】
As described above, according to the first aspect of the present application, when the solenoid body is energized, the movable member is magnetically attracted to the fixed member, and is operatively connected to the movable member by the thrust, so that the through hole of the fixed member is formed. The valve body integrated with the first rod slidably inserted into the valve body moves to the valve seat side, and the valve body comes into contact with the valve seat to close and seal the flow path opened to the valve seat. .
[0111]
At this time, even if the through-hole of the fixing member receiving the first rod and the flow path are misaligned, they come into contact with and separate from each other because the part where the valve body and the valve seat come and go is flat. Since there is no change in the part, it is reliably sealed when the valve is closed. That is, the sealing performance can be improved.
[0112]
According to the second aspect of the present invention, the convex portion that enters the flow passage in the flat portion of the valve body has a tapered shape whose diameter decreases toward the flow passage side, so that the fluid flows along the taper. Flows, it is possible to prevent a sudden change in the flow rate (pressure) when the valve element is separated from the valve seat and the flow path starts to open. Thus, control performance can be improved.
[0113]
According to the third invention of the present application, the valve body is not affected by the pressure difference at the second port due to the balance of the force of the solenoid valve, and responds to the pressure applied to the third port. The bellows assembly is provided so as to extend and contract, so that the second rod operatively connected to the bellows assembly moves to move the valve body toward and away from the valve seat to maintain the pressure on the third port constant. The automatic pressure adjustment is performed.
[0114]
Even at this time, even if the through-hole of the fixing member receiving the first rod and the flow path are misaligned, the portion where the valve body and the valve seat come and go is flat, so Since there is no change in the part to be adjusted, it is reliably sealed when the valve is closed, and the automatic pressure adjustment is performed with high accuracy. That is, it is possible to improve the sealing performance and control performance.
[0115]
Further, according to the fourth aspect of the present invention, since the convex portion that enters the flow path in the flat portion of the valve element according to the third aspect has a tapered shape whose diameter decreases toward the flow path side, Since the fluid flows along the taper, it is possible to prevent a sudden change in the flow rate (pressure) when the valve element is separated from the valve seat and the flow path starts to open. Thereby, control performance can be further improved.
[0116]
Further, according to the fifth invention of the present application, even when the external pressure is high and the bellows assembly is displaced from the mounting position due to vibration or the like, the bellows is regulated by the inner peripheral surface of the guide portion, and the bellows assembly is reduced. Since the projection extends along the inner peripheral surface of the tapered portion that reduces the diameter, the deviation from the mounting position is corrected, the locking phenomenon caused by biting can be avoided, and the valve opening / closing function is not lost. That is, the reliability of the valve can be improved.
[Brief description of the drawings]
FIG. 1 is an overall longitudinal sectional view of a solenoid valve according to an embodiment of the present invention.
FIG. 2 is an enlarged view of a portion E in FIG. 1 and shows an axial deviation between a through hole of a center post and a flow path.
FIG. 3 is an enlarged view around a bellows assembly of a solenoid valve according to one embodiment of the present invention.
FIG. 4 is a view showing dimensions of a bellows assembly and an adjustment screw of a solenoid valve according to one embodiment of the present invention.
FIG. 5 is an overall vertical sectional view of a conventional solenoid valve.
6 is an enlarged view of a portion D in FIG. 5 and shows an axial deviation between a through hole of a center post and a flow path.
FIG. 7 is a view showing a locking phenomenon of a bellows assembly in a conventional solenoid valve.
[Explanation of symbols]
1 Solenoid valve
2 solenoid
2A valve body
3 Solenoid body
4 plunger (movable member)
41 recess
42 spring B (second biasing means)
5 Center post (fixing member)
51 Outward flange
52 Through hole
53 passage
54 recess
6. Rod A (first rod)
7 cases
71 Inward flange
72 Step surface
8 hollow part
9 bobbins
10 coils
11 Spacer
11A convex
12 Upper plate
12A Outward flange
12B tubular part
13 Bracket
14 Hollow part of solenoid body
15 Bearing
16 valve body
16A small diameter part
16B Medium diameter part
16C Large diameter part
16D flat part
16E convex
17 Valve room
18 Valve body
18A recess
18B hole
18C storage section
19 Valve seat
20 channels
21 Spring A (first biasing means)
22 Inflow port (first port)
22A filter
23 control port (second port)
24 connecting passage
25 cover
26 Adjust screw
26A recess
26B Bottom of recess
26a straight section
26b taper part
26c step
27 Bellows part
27A Projection
27B Projection end face
28 Rod B (second rod)
28A Large diameter part
28B small diameter part
29 Rod holder
30 Bellows assembly
31 Bellows
32 pin A
32A recess
33 spring C (third biasing means)
34 pin B
35 Suction port (third port)
36 orifice

Claims (3)

An inner hollow solenoid body, a movable member made of a magnetic material reciprocally inserted into the hollow interior of the solenoid body, a fixed member made of a magnetic material provided coaxially opposite the movable member, and A through hole formed in the fixing member in the axial direction, a first rod slidably inserted into the through hole, and a valve provided integrally with the first rod and provided in the valve body A valve element reciprocally inserted into the chamber, a valve seat provided in the valve chamber to which the valve element contacts and separates, a flow path opening to the valve seat, and separating the valve element from the valve seat A first urging means for urging in the direction, a second urging means for urging the movable member to the first rod side so that the movable member comes into contact with the first rod; A bellows assembly comprising: a bellows of vacuum; A second rod operatively connected to the valve assembly, the valve body having a first port communicating the outside with the valve chamber, a second port communicating the outside with the flow path, A communication path communicating between the movable member and the fixed member via two ports and the outside, a storage part storing the bellows assembly, and a third part communicating the outside and the inside of the storage part. And a hole provided coaxially with the flow passage and into which the second rod is slidably inserted. The second rod is provided on the valve body side through the flow passage. A solenoid valve in which the diameter of the through hole is substantially equal to the diameter of the flow passage, wherein a portion where the valve body and the valve seat come and go is a flat surface. A convex portion that enters the flow path is provided in a flat portion of the valve body, of which a portion where the valve body and the valve seat come and go is a flat surface, and the convex portion has a tapered shape whose diameter decreases toward the flow path side. The solenoid valve according to claim 1 , wherein: At the end of the bellows assembly opposite to the side to which the second rod is connected, a stepped projection having a smaller diameter than the bellows and projecting in the direction of expansion and contraction of the bellows assembly is formed. A concave portion having a shape substantially matching the outer shape of the end of the bellows assembly for mounting the bellows assembly is provided on a surface of the storage portion facing the portion, and the concave portion is provided on an opening side of the concave portion. A provided guide portion having an inner peripheral surface substantially parallel to the direction of expansion and contraction of the bellows assembly is provided, and the guide portion is adjacent to the guide portion via a step portion, and has a diameter smaller than the guide portion and reduced toward the bottom surface of the concave portion. A tapered portion, and when the bellows assembly displaced from the mounting position of the concave portion extends while the bellows is regulated by the inner peripheral surface of the guide portion, the projecting portion is formed inside the tapered portion. By riding on the peripheral surface, the recess Claim 1 or 2 solenoid valve, wherein the modifying the deviation from assigned position.

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