JPH0211812A - Variable valve timing device - Google Patents

Variable valve timing device

Info

Publication number
JPH0211812A
JPH0211812A JP16337688A JP16337688A JPH0211812A JP H0211812 A JPH0211812 A JP H0211812A JP 16337688 A JP16337688 A JP 16337688A JP 16337688 A JP16337688 A JP 16337688A JP H0211812 A JPH0211812 A JP H0211812A
Authority
JP
Japan
Prior art keywords
cam
fork
valve
block
shifter fork
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP16337688A
Other languages
Japanese (ja)
Inventor
Yonosuke Yokoki
横木 要之助
Ryuichi Inaba
稲葉 隆一
Seiji Kamata
鎌田 清司
Ichizo Kuriyama
栗山 市三
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Suzuki Motor Corp
Original Assignee
Suzuki Motor Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Suzuki Motor Corp filed Critical Suzuki Motor Corp
Priority to JP16337688A priority Critical patent/JPH0211812A/en
Publication of JPH0211812A publication Critical patent/JPH0211812A/en
Pending legal-status Critical Current

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01LCYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L13/00Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
    • F01L13/0015Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque
    • F01L13/0036Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque the valves being driven by two or more cams with different shape, size or timing or a single cam profiled in axial and radial direction
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01LCYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L13/00Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
    • F01L13/0015Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque
    • F01L13/0036Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque the valves being driven by two or more cams with different shape, size or timing or a single cam profiled in axial and radial direction
    • F01L2013/0052Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque the valves being driven by two or more cams with different shape, size or timing or a single cam profiled in axial and radial direction with cams provided on an axially slidable sleeve

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Valve-Gear Or Valve Arrangements (AREA)
  • Valve Device For Special Equipments (AREA)

Abstract

PURPOSE:To markedly simplify the structure of the device in comparison with a valve timing device using a hydraulic cylinder actuator by shift-operating a cam block by a motor-driven actuator. CONSTITUTION:During the operation of an engine in a low revolution range, a shifter fork 6 is at the position shown by the full line, and a cam block 2 is positioned at the position where a low speed cam 3 is positioned directly over a valve 30 by the fork parts 6a and 6b. The valve 30 is opened and closed by the cam 3 through a shim 31 and a locker arm 32. When the revolution speed increases over a certain value, a cam selection signal is outputted from a controller, and an electric motor 20 is revolved in the normal direction on the basis of the signal, and a pinion 8 is revolved in the (f) direction, and the fork 6 is shifted leftward. At this time, the fork part 6a presses the edge surface 2a, and the block 2 is moved leftward together with the fork 6. Then, the fork 6 stops at the time when a high speed cam 4 is positioned directly over the valve 30, and the valve 30 is opened and closed by the cam 4 through the shim 31 and the arm 32.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、可変バルブタイミング装置に関するものであ
る。
DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a variable valve timing device.

〔従来技術〕[Prior art]

昨今のエンジンには、出力向上や燃費低減を目的として
、エンジンの負荷状態に応してバルブタイミングやバル
ブリフト量を変化させる可変バルブタイミング装置を備
えたものがある。
Some modern engines are equipped with variable valve timing devices that change valve timing and valve lift according to engine load conditions in order to improve output and reduce fuel consumption.

第2図は、上記可変バルブタイミング装置の一例を示す
ものである。この装置Aては、低速用のカムプロフィル
を有する低速用バルブ開閉カムBと高速用のカムプロフ
ィルを有する高速用バルブ開閉カムCとを並設して一体
に形成したカムブロックDか、カムシャフトEに移動自
在にスプライン結合されており、さらに上記カムブロッ
クDにはシフタフォークFが係合している。上記シフタ
フォークFは、エンンンの回転数に基づいてカムシャフ
トEの軸線方向に沿って移動動作し、上記カムブロック
Dを移動させる。これにより、カムブロックDにおける
低速用カムBもしくは高速用カムCか、エンジン回転数
に応して選択的にバルブGの直上に占位して上記バルブ
Gを開閉動作させることとなり、エンジンが効率よく運
転される。
FIG. 2 shows an example of the variable valve timing device. This device A is either a cam block D, which is integrally formed with a low-speed valve opening/closing cam B having a low-speed cam profile and a high-speed valve opening/closing cam C having a high-speed cam profile, or a camshaft. The cam block D is movably spline connected to the cam block D, and a shifter fork F is engaged with the cam block D. The shifter fork F moves along the axial direction of the camshaft E based on the rotation speed of the engine, and moves the cam block D. As a result, either the low-speed cam B or the high-speed cam C in the cam block D is selectively positioned directly above the valve G depending on the engine speed to open and close the valve G, making the engine more efficient. Well driven.

なお、図中符号Hは、5OHC型エンンンにおけるロッ
カアームである。
In addition, the symbol H in the figure is a rocker arm in the 5OHC type engine.

ところで上記装置Aでは、シフタフォークFは油圧シリ
ンダアクチュエータGのロッドHに取り付けられており
、オイルパンIからオイルポンプJを介して油室G′に
送供される作動油によって上記シフタフォークFが作動
される。なお、図中符号には、エンジン回転数に基づい
て油室G′への作動油供給量を制御するコントローラで
ある。
By the way, in the above device A, the shifter fork F is attached to the rod H of the hydraulic cylinder actuator G, and the shifter fork F is moved by the hydraulic oil supplied from the oil pan I to the oil chamber G' via the oil pump J. activated. Note that the reference numeral in the figure indicates a controller that controls the amount of hydraulic oil supplied to the oil chamber G' based on the engine speed.

このように油圧シリンダアクチュエータでシフタフォー
クを動作させる構造では、油圧発生装置や油圧制御装置
を構成する上記オイルパンI、オイルポンプJ1および
コントローラに等の数多くの補機類を必要とし、さらに
油圧回路には作動油漏れ対策を施す必要があるため、機
構が煩雑、かつ大掛かりなものとなっていた。
This structure in which the shifter fork is operated by a hydraulic cylinder actuator requires a large number of auxiliary equipment such as the oil pan I, oil pump J1, and controller that constitute the hydraulic pressure generating device and hydraulic control device, and also requires a hydraulic circuit. Since it is necessary to take measures against hydraulic oil leakage, the mechanism is complicated and large-scale.

〔発明の目的〕 本発明は、上記実状に鑑みて、構造の簡単な可変バルブ
タイミング装置を提供することを目的とする。
[Object of the Invention] In view of the above-mentioned circumstances, an object of the present invention is to provide a variable valve timing device with a simple structure.

〔発明の構成〕[Structure of the invention]

そこて本発明ては、シフタフォークに電気アクチュエー
タを連係し、この電気アクチュエータによりシフタフォ
ークを介してカムブロックを移動させるようにして上記
目的を達成した。
Therefore, in the present invention, an electric actuator is linked to the shifter fork, and the electric actuator moves the cam block via the shifter fork, thereby achieving the above object.

〔実施例〕〔Example〕

以下、本発明を図面に基づいて説明する。 Hereinafter, the present invention will be explained based on the drawings.

第1図は本発明に関わる可変バルブタイミング装置を、
S OHC型エンジンに適用した例を示している。カム
シャフト1には、カムブロック2が上記カムシャフト1
の軸線方向に沿って移動自在にスプライン結合されてお
り、上記カムブロック2は、低速用バルブ開閉カム3と
高速用バルブ開閉カム4とが互いに並設されかつ一体に
形成されている。カムシャフト1の上方域には、該カム
シャフト1と平行してガイドシャフト5が延設されてお
り、このガイドシャフト5には、ンフタフォ−ク6が遊
嵌している。このシフタフォーク6には、そのペースブ
ロック6′の両端部にそれぞれフォーク部6a、6bが
形成されており、これらフォーク部6a  6bはそれ
ぞれカムブロック2の端面2a、2bに臨んで配設され
ている。さらにシフタフォーク6のベースブロック6′
上面には、ガイドシャフト5の軸方向に沿ってラック7
が形成されており、このラック7にはピニオン8が噛合
している。該ピニオン8は、シリンダベツド9に回転自
在に支承されたシャフト10の一端に固設されており、
上記シャフト10の他端には従動プーリ11が固設され
ている。従動プーリ11には、駆動プーリ12との間に
伝動ベルト13が巻き掛けられている。上記駆動プーリ
12は、電気アクチュエータとしての電動モータ20の
駆動軸20aに固設されており、言い換えれば、上記電
動モータ20は、駆動プーリ12、伝動ベルト13、従
動プーリ11、シャフト10、およびピニオン8、ラッ
ク7から成る動力伝達機構100を介してシフタフォー
ク6と連係している。
Figure 1 shows a variable valve timing device according to the present invention.
An example of application to an SOHC type engine is shown. A cam block 2 is attached to the camshaft 1.
The cam block 2 includes a low-speed valve opening/closing cam 3 and a high-speed valve opening/closing cam 4 arranged side by side and integrally formed. A guide shaft 5 extends above the camshaft 1 in parallel with the camshaft 1, and a lifter fork 6 is loosely fitted onto the guide shaft 5. The shifter fork 6 has fork portions 6a and 6b formed at both ends of the pace block 6', and these fork portions 6a and 6b are arranged facing the end surfaces 2a and 2b of the cam block 2, respectively. There is. Furthermore, the base block 6' of the shifter fork 6
A rack 7 is provided on the upper surface along the axial direction of the guide shaft 5.
A pinion 8 is meshed with the rack 7. The pinion 8 is fixed to one end of a shaft 10 rotatably supported by a cylinder bed 9.
A driven pulley 11 is fixed to the other end of the shaft 10. A transmission belt 13 is wound around the driven pulley 11 and the drive pulley 12 . The drive pulley 12 is fixed to a drive shaft 20a of an electric motor 20 as an electric actuator. In other words, the electric motor 20 includes the drive pulley 12, transmission belt 13, driven pulley 11, shaft 10, and pinion. 8. It is linked to the shifter fork 6 via a power transmission mechanism 100 consisting of a rack 7.

いま、エンジンが低回転数域で運転されている場合、シ
フタフォーク6は第1図(a)中に実線で示す位置に占
位し、カムブロック2はフォーク部6a、6bによって
、低速用カム3がバルブ30の直上に占位するよう位置
決めされている。
When the engine is currently operating in a low rotational speed range, the shifter fork 6 is in the position shown by the solid line in FIG. 3 is positioned directly above the valve 30.

かくして上記バルブ30は、シム31およびロッカアー
ム32を介して低速用カム3によって開閉動作される。
Thus, the valve 30 is opened and closed by the low speed cam 3 via the shim 31 and rocker arm 32.

エンジンの回転数が上昇し、予設定値を越えると、図示
していないコントローラからカム切換信号(低−高)が
出力される。電動モータ20は上記信号に基づいて正回
転してピニオン8を第1図(a)中の矢印f方向へ回転
させ、これによりシフタフォーク6が図中左方へ移動さ
れる。このとき、シフタフォーク6のフォーク部6aが
カムブロック2の端面2aを押圧することによって、該
カムブロック2はシフタフォーク6と共に左行する。高
速用カム4がバルブ30の直上に占位した時点でシフタ
フォーク6は停止し、これにより上記バルブ30は、シ
ム31、ロッカーアーム32を介して高速用カム4によ
って開閉動作される。
When the engine speed increases and exceeds a preset value, a cam switching signal (low-high) is output from a controller (not shown). The electric motor 20 rotates forward based on the above signal to rotate the pinion 8 in the direction of arrow f in FIG. 1(a), thereby moving the shifter fork 6 to the left in the figure. At this time, the fork portion 6a of the shifter fork 6 presses the end surface 2a of the cam block 2, so that the cam block 2 moves to the left together with the shifter fork 6. When the high-speed cam 4 is positioned directly above the valve 30, the shifter fork 6 stops, and the valve 30 is thereby opened and closed by the high-speed cam 4 via the shim 31 and rocker arm 32.

エンジンの回転数が高速回転数域から下降し、予設定値
を下回ると、コントローラ(図示せず)からカム切換信
号(高−低)が出力される。電動モータ20は上記信号
に基づいて逆回転してビニオン8を矢印r方向へ回転さ
せ、これによりシフタフォーク6が左行される。このと
き、フォーク部6bがカムブロック2の端面2bを押圧
することによって、該カムブロック2はシフタフォーク
6と共に右行する。低速用カム3がバルブ30の直上に
占位した時点でシフタフォーク6は停止し、これにより
上記バルブ30は、シム31、ロッカーアーム32を介
して低速用カム3によって開閉動作される。
When the engine speed drops from the high speed range and falls below a preset value, a cam switching signal (high-low) is output from a controller (not shown). The electric motor 20 reversely rotates based on the above signal to rotate the pinion 8 in the direction of arrow r, thereby moving the shifter fork 6 to the left. At this time, the fork portion 6b presses the end surface 2b of the cam block 2, so that the cam block 2 moves to the right together with the shifter fork 6. When the low-speed cam 3 is positioned directly above the valve 30, the shifter fork 6 stops, and the valve 30 is thereby opened and closed by the low-speed cam 3 via the shim 31 and rocker arm 32.

なお、本例では巻き掛は伝動機構を介して電動モータと
ビニオンを連係しているが、電動モータにピニオンを直
接取り付けてもよい。また、電動モータの回転出力をシ
フタフォークの直線運動に変換する手段として、ラック
・ピニオン以外の適宜な機構を採用し得ることは勿論で
ある。さらに電気アクチュエータとしてプランジャ型ソ
レノイドを採用し、そのプランジャにシフタフォークを
設けて該シフタフォークを直線運動させるよう構成する
ことも可能である。また、本発明はDOHC型のエンジ
ンにも有効に適用することができる。
In this example, the electric motor and the pinion are connected to each other via a transmission mechanism, but the pinion may be directly attached to the electric motor. Further, as a means for converting the rotational output of the electric motor into linear motion of the shifter fork, it is of course possible to employ an appropriate mechanism other than the rack and pinion. Furthermore, it is also possible to employ a plunger type solenoid as the electric actuator, provide a shifter fork on the plunger, and make the shifter fork move linearly. Further, the present invention can be effectively applied to a DOHC type engine.

さらにカムブロックを3つ以上のカムから一体に形成し
てもよいことは言うまでもない。
Furthermore, it goes without saying that the cam block may be integrally formed from three or more cams.

〔発明の効果〕〔Effect of the invention〕

以上、詳述した如く、本発明に関わる可変バルブタイミ
ング装置によれば、電気アクチュエタによってカムブロ
ックを移動動作させるように構成したので、油圧シリン
ダアクチュエータを用いていた従来構造と比較して、装
置の構造を大幅に簡略化することか可能となった。
As detailed above, according to the variable valve timing device according to the present invention, the cam block is moved by an electric actuator, so compared to the conventional structure that uses a hydraulic cylinder actuator, the device is more efficient. It became possible to greatly simplify the structure.

【図面の簡単な説明】[Brief explanation of the drawing]

第1図(a)は本発明に関わる可変バルブタイミング装
置を示す要部断面図、第1図(b)は第1図(a)のI
−I線断面図であり、第2図は従来の可変バルブタイミ
ング装置の要部断面側面図である。 1 ・カムシャフト、2・・カムブロック、3・・低速
用バルブ開閉カム、 4 高連用バルブ開閉カム、6・・・シフタフォーク、
6a、6b・・フォーク部、7・・ラック、8 ピニオ
ン、11・・・従動プーリ、12・・駆動プーリ、13
・・・伝動ベルト、20・・・電動モータ、30・・・
バルブ、100・・・動力伝達機構。 図
FIG. 1(a) is a cross-sectional view of a main part of a variable valve timing device according to the present invention, and FIG. 1(b) is an I of FIG. 1(a).
-I line sectional view, and FIG. 2 is a sectional side view of main parts of a conventional variable valve timing device. 1.Camshaft, 2..Cam block, 3..Low speed valve opening/closing cam, 4.High speed valve opening/closing cam, 6..Shifter fork,
6a, 6b...fork part, 7...rack, 8 pinion, 11...driven pulley, 12...drive pulley, 13
...Transmission belt, 20...Electric motor, 30...
Valve, 100...power transmission mechanism. figure

Claims (1)

【特許請求の範囲】[Claims] それぞれカムプロフィルの異なる複数個のバルブ開閉カ
ムを互いに並設して一体に形成したカムブロックを、カ
ムシャフトに回転不可能かつ軸方向に沿って移動自在に
嵌合するとともに、上記カムブロックに係合するシフタ
フォークを上記カムシャフトの軸方向に沿って移動自在
に配設し、さらに上記シフタフォークに電気アクチュエ
ータを連係し、該電気アクチュエータによって上記シフ
タフォークを介して上記カムブロックを移動させること
により、バルブを動作させるカムを選択するようにした
ことを特徴とする可変バルブタイミング装置。
A cam block, which is integrally formed by arranging a plurality of valve opening/closing cams with different cam profiles in parallel, is fitted to the camshaft so as to be non-rotatable and movable along the axial direction, and is engaged with the cam block. A matching shifter fork is disposed movably along the axial direction of the camshaft, an electric actuator is linked to the shifter fork, and the electric actuator moves the cam block via the shifter fork. , a variable valve timing device characterized in that a cam for operating a valve is selected.
JP16337688A 1988-06-30 1988-06-30 Variable valve timing device Pending JPH0211812A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP16337688A JPH0211812A (en) 1988-06-30 1988-06-30 Variable valve timing device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP16337688A JPH0211812A (en) 1988-06-30 1988-06-30 Variable valve timing device

Publications (1)

Publication Number Publication Date
JPH0211812A true JPH0211812A (en) 1990-01-16

Family

ID=15772708

Family Applications (1)

Application Number Title Priority Date Filing Date
JP16337688A Pending JPH0211812A (en) 1988-06-30 1988-06-30 Variable valve timing device

Country Status (1)

Country Link
JP (1) JPH0211812A (en)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5080053A (en) * 1989-11-15 1992-01-14 Jaguar Cars Limited Rotary drives
JPH108928A (en) * 1996-03-25 1998-01-13 Dr Ing H C F Porsche Ag Valve driving device for internal combustion engine
WO2010137159A1 (en) * 2009-05-29 2010-12-02 トヨタ自動車株式会社 Variable valve device for internal combustion engine
US8955476B2 (en) 2009-11-25 2015-02-17 Toyota Jidosha Kabushiki Kaisha Variable valve operating apparatus for internal combustion engine
WO2017045736A1 (en) * 2015-09-15 2017-03-23 Daimler Ag Valve train device, in particular for an internal combustion engine
WO2017137146A1 (en) * 2016-02-10 2017-08-17 Daimler Ag Valve train device
WO2018068874A1 (en) * 2016-10-12 2018-04-19 Daimler Ag Valve train device
WO2018077451A1 (en) * 2016-10-29 2018-05-03 Daimler Ag Valve train device
WO2018077452A1 (en) * 2016-10-29 2018-05-03 Daimler Ag Valve train device
EP3561243A1 (en) * 2018-04-26 2019-10-30 Volvo Car Corporation Camshaft arrangement

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5080053A (en) * 1989-11-15 1992-01-14 Jaguar Cars Limited Rotary drives
JPH108928A (en) * 1996-03-25 1998-01-13 Dr Ing H C F Porsche Ag Valve driving device for internal combustion engine
WO2010137159A1 (en) * 2009-05-29 2010-12-02 トヨタ自動車株式会社 Variable valve device for internal combustion engine
US8191520B2 (en) 2009-05-29 2012-06-05 Toyota Jidosha Kabushiki Kaisha Variable valve operating apparatus for internal combustion engine
US8955476B2 (en) 2009-11-25 2015-02-17 Toyota Jidosha Kabushiki Kaisha Variable valve operating apparatus for internal combustion engine
WO2017045736A1 (en) * 2015-09-15 2017-03-23 Daimler Ag Valve train device, in particular for an internal combustion engine
WO2017137146A1 (en) * 2016-02-10 2017-08-17 Daimler Ag Valve train device
WO2018068874A1 (en) * 2016-10-12 2018-04-19 Daimler Ag Valve train device
WO2018077451A1 (en) * 2016-10-29 2018-05-03 Daimler Ag Valve train device
WO2018077452A1 (en) * 2016-10-29 2018-05-03 Daimler Ag Valve train device
CN109863283A (en) * 2016-10-29 2019-06-07 戴姆勒股份公司 Valve device
US10801376B2 (en) 2016-10-29 2020-10-13 Daimler Ag Valve train device
CN109863283B (en) * 2016-10-29 2021-04-30 戴姆勒股份公司 Valve gear
EP3561243A1 (en) * 2018-04-26 2019-10-30 Volvo Car Corporation Camshaft arrangement
US10550735B2 (en) 2018-04-26 2020-02-04 Volvo Car Corporation Camshaft arrangement

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