JPS61136044A - Method of operating hydraulic clutch in hydraulically operated speed change gear unit - Google Patents

Method of operating hydraulic clutch in hydraulically operated speed change gear unit

Info

Publication number
JPS61136044A
JPS61136044A JP25604684A JP25604684A JPS61136044A JP S61136044 A JPS61136044 A JP S61136044A JP 25604684 A JP25604684 A JP 25604684A JP 25604684 A JP25604684 A JP 25604684A JP S61136044 A JPS61136044 A JP S61136044A
Authority
JP
Japan
Prior art keywords
clutch
hydraulic
pressure
voltage
hydraulic clutch
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
JP25604684A
Other languages
Japanese (ja)
Inventor
Tetsuya Nishida
哲也 西田
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.)
Kubota Corp
Original Assignee
Kubota 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 Kubota Corp filed Critical Kubota Corp
Priority to JP25604684A priority Critical patent/JPS61136044A/en
Publication of JPS61136044A publication Critical patent/JPS61136044A/en
Pending legal-status Critical Current

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  • Gear-Shifting Mechanisms (AREA)

Abstract

PURPOSE:To make the operation of a hdyraulic gear shift clutch smooth, by providing an electromagnetic proportional pressure reduction valve in a hydraulic supply system for the hydraulic gear shift clutch so that the electromagnetically exciting voltage is made to be high upon starting of turn-on of the clutch and thereafter, is gradually increased from a set voltage. CONSTITUTION:An electromagnetic proportional pressure reduction valve 17 is provided in a hydraulic supply system for a hydraulic gear shift clutch C, and the electromagnetically exciting voltage of this valve 17 is set such that it is initially high and is thereafter gradually increased from a set voltage which is lower than the initial exciting voltage. With this arrangement, the hydraulic pressure is rapidly increased from a minimum pressure at which the hydraulic clutch operates to restrain a dead time, and further, it is possible to make the pressure rising characteristic curve gentle, thereby the operation of the clutch is made to be smooth.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は変速用油圧クラッチへの圧油供給系統に電磁比
例減圧弁を設け、この電磁比例減圧弁の励磁電圧を制御
することによって、油圧クラッチへの圧力を制御可能に
構成しである油圧操作式ギヤ変速装置の油圧クラッチ作
動方法に関する。
[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides an electromagnetic proportional pressure reducing valve in the pressure oil supply system to the hydraulic clutch for transmission, and controls the excitation voltage of the electromagnetic proportional pressure reducing valve to reduce hydraulic pressure. The present invention relates to a method for operating a hydraulic clutch in a hydraulically operated gear transmission configured to be able to control pressure to the clutch.

〔従来の技術〕[Conventional technology]

この種の油圧クラッチの作動に対する比例減圧弁への励
磁電圧の制御方法として考えられるものに、次のような
ものがある。
Possible methods of controlling the excitation voltage to the proportional pressure reducing valve for the operation of this type of hydraulic clutch include the following.

つまり、第5図に示すように、クラッチが安定した伝動
状態を現出する為の基準圧に相当する励磁電圧を初期の
状態から連続して与える方法がある。
That is, as shown in FIG. 5, there is a method of continuously applying an excitation voltage corresponding to a reference pressure from an initial state so that the clutch exhibits a stable transmission state.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

しかし、この場合には油圧クラッチの昇圧カーブが立上
り時に前記基準圧を越えた状態で、以後徐々に基準圧に
低下する過渡現象を示すので、立上り時のクラッチの作
動ショックが大きく、好ましくなかった。 従って、こ
のような現象を踏えて、第6図に示すように、階段状の
パルス電圧を与える方法あるが、この場合には電磁比例
弁の立上り抵抗が大きく、油圧クラッチ昇圧が始まるタ
イミングが遅れるとになり、無駄時間が発生していた。
However, in this case, the pressure increase curve of the hydraulic clutch shows a transient phenomenon in which the pressure exceeds the reference pressure at the time of startup and then gradually decreases to the reference pressure, so the clutch operation shock at the time of startup is large, which is not desirable. . Therefore, in consideration of this phenomenon, there is a method of applying a stepped voltage pulse as shown in Figure 6, but in this case, the rising resistance of the electromagnetic proportional valve is large, and the timing at which the hydraulic clutch pressure starts is delayed. This resulted in wasted time.

本発明の目的は変速ショック少なくかつ無駄時間少な(
変速可能な油圧クラッチの作動方法を提案する点にある
The purpose of the present invention is to reduce shift shock and waste time (
The purpose of this invention is to propose an operating method for a hydraulic clutch that can change gears.

〔問題点を解決するための手段〕[Means for solving problems]

本発明の特徴は変速用油圧クラッチへの圧油供給系統に
電磁比例減圧弁を設け、クラッチオン作動時における前
記減圧弁への励磁電圧を、初期のものを大きく、以後を
初期励磁電圧よりも低い設定電圧から徐々に大きくなる
ものに設定してクラッチの昇圧速度に対応させてある点
にあり、その作用効果は次の通りである。
A feature of the present invention is that an electromagnetic proportional pressure reducing valve is provided in the pressure oil supply system to the hydraulic clutch for shifting, and when the clutch is activated, the excitation voltage to the pressure reducing valve is initially set to be higher than the initial excitation voltage. The point is that the set voltage is set gradually from a low set voltage to a value that increases to correspond to the pressure increasing speed of the clutch, and its effects are as follows.

〔作 用〕[For production]

つまり、初期のものを大きくして、油圧クラッチが作動
する最低圧まで急速に昇圧して、無駄時間を抑えるとと
もに、以後の励磁電圧を初期のものより低くして、それ
から徐々に大きな電圧のものにすることによって、昇圧
カーブの急激な立−トリによる基準圧を越えるといった
ことを避けて昇圧カーブを緩やかなものにでき、円滑な
りラッチ作動が得られる方法をとっている。
In other words, the initial voltage is increased to rapidly increase the voltage to the minimum pressure at which the hydraulic clutch operates, reducing wasted time, and the subsequent excitation voltage is lower than the initial voltage, and then gradually increases the voltage. By doing so, the pressure increase curve can be made gentle without exceeding the reference pressure due to a sudden rise in the pressure rise curve, and a smooth latch operation can be obtained.

〔発明の効果〕 その結果、無駄時間巾なく、しかも、変速ショックが少
ないので、運転操作性を良好にできる。
[Effects of the Invention] As a result, there is no wasted time and there is little shift shock, so driving operability can be improved.

〔実施例〕〔Example〕

第2図はトラクタに装備のミッショケース(M)内の伝
動構造を示し、エンジン(E)に連動連結させた入力軸
(1)と走行用第1伝動軸(2)とに亘って、4段切換
自在なシンクロメソシュ式主ギヤ変速装W()I+)を
設け、第1伝動軸(2)と走行用第2伝動軸(3)との
間に、摩擦板式油圧クラッチ(C)を設け、第2伝動軸
(3)の出力を正逆転変更するシンクロメソシュ式前後
進ギヤ変速装W(Hz)、それからの出力を高低2段に
切換自在なシンクロメソシュ式第1副ギヤ変速装Ft(
Is)、及び、それからの出力を高低2段に切換自在な
第2副ギヤ変速装置f(H4)の夫々を設け、そして、
第2副ギヤ変速装置(H4)の出力を後輪(4)の差動
機構(4^)、及び、前輪(5)の差動機構(5A)に
伝動させるように構成しである。
Figure 2 shows the transmission structure inside the transmission case (M) installed on the tractor, and the transmission structure between the input shaft (1) interlocked with the engine (E) and the first transmission shaft (2) for traveling is shown. A synchromesh type main gear transmission W()I+) that can freely change gears is provided, and a friction plate type hydraulic clutch (C) is installed between the first transmission shaft (2) and the second transmission shaft for traveling (3). A synchromesh type forward/reverse gear transmission W (Hz) that changes the output of the second transmission shaft (3) in forward and reverse directions, and a synchromesh type first auxiliary gear transmission that can freely switch the output from the second transmission shaft (3) into two high and low stages. Mounting Ft (
Is) and a second auxiliary gear transmission f(H4) capable of freely switching the output therefrom into two high and low stages, and
The output of the second sub-gear transmission (H4) is configured to be transmitted to the differential mechanism (4^) for the rear wheels (4) and the differential mechanism (5A) for the front wheels (5).

前記入力軸(1)の動力を4段に変速して動力取出伝動
軸(6)に伝動するシンクロメソシュ式ギヤ変速装置(
7)を設けると共に、伝動軸(6)と動力取出軸(8)
との間に、中箱伝動軸(9)を設け、もって、動力取出
軸(8)を変速できるように構成しである。
A synchromesh type gear transmission device (1) that changes the power of the input shaft (1) in four stages and transmits it to the power output transmission shaft (6).
7), as well as a transmission shaft (6) and a power take-off shaft (8).
An inner box transmission shaft (9) is provided between the two and is configured so that the speed of the power take-off shaft (8) can be changed.

次に、走行用伝動系に対する変速操作構造について、第
2図及び第3図に基づいて詳述する。
Next, the speed change operation structure for the driving transmission system will be described in detail with reference to FIGS. 2 and 3.

すなわち、主ギヤ変速装置(H1)に、択一的に作動さ
れる変速用シフター操作用油圧シリンダ(IOA) 、
 (IOR)の2個を付設すると共に、前後進ギヤ変速
装置(H2)及び第1副ギヤ変速装置(H3)の夫々に
、変速シフター操作用油圧シリンダ(IIL (12)
の1個を付設し、そして、前記伝動クラッチ(C)に、
入り操作用の油圧シリンダ(13)を付設しである。
That is, the main gear transmission (H1) includes a hydraulic cylinder (IOA) for operating a gear shifter that is selectively operated;
(IOR), and a hydraulic cylinder (IIL (12)) for operating the transmission shifter is attached to each of the forward/reverse gear transmission (H2) and the first auxiliary gear transmission (H3).
attached to the transmission clutch (C), and
A hydraulic cylinder (13) for entry operation is attached.

前記主ギヤ変速用油圧シリンダ(IOA) 、 (IO
B)及び前記第1副変連用油圧シリンダ(12)夫々に
対する主制御弁(vl)、並びに、前記前後進変速用油
圧シリンダ(11)に対する補助制御弁(v2)を、油
圧ポンプ(16)に並列接続しである。 そして、前記
各油圧シリンダ(10^)・・のピストンを摺動スプー
ルとして兼用利用する状態で3位置切換弁(Sl)、 
(32) 、 (S3) 、 (S4)の4個を構成し
、前後進変速用油圧シリンダ(11)にて構成した切換
弁(S、)からの圧油をクラッチ操作用油圧シリンダ(
13)に供給する油路(14)を設けると共に、その油
路(14)を開閉するためのパイロット圧操作式切換弁
(TI)、 (T2) 、 (T3)の3個を、直列状
に並べる状態で、且つ、主ギヤ変速用油圧シリンダ(I
OA) 、 (IOB)及び第1副変速用油圧シリンダ
(12)の夫々にて構成した切換弁(S3) 、(S4
)及び(S2)からの圧油にて操作される状態で設け、
もって、クラッチ操作用シリンダ(13)の作動を制御
する弁(St)、 (TI)、(T*)、(T3)を、
主ギヤ変速装置(Il+)、前後進ギヤ変速装置f(H
z)、及び、第1副ギヤ変速装置(H3)の伝動状態に
おいてのみ入り操作位置に切換えるべく、変速操作に伴
って自動的に切換操作されるように構成しである。
The main gear shifting hydraulic cylinder (IOA), (IO
B) and the main control valve (vl) for each of the first auxiliary transmission hydraulic cylinders (12), and the auxiliary control valve (v2) for the forward/reverse transmission hydraulic cylinder (11) to the hydraulic pump (16). Connected in parallel. and a 3-position switching valve (Sl) in a state in which the pistons of each of the hydraulic cylinders (10^) are also used as sliding spools;
(32), (S3), and (S4), and the pressure oil from the switching valve (S,) constituted by the forward/reverse shift hydraulic cylinder (11) is transferred to the clutch operation hydraulic cylinder (
13), and three pilot pressure-operated switching valves (TI), (T2), and (T3) are arranged in series to open and close the oil passage (14). The main gear shifting hydraulic cylinder (I
(OA), (IOB) and the first sub-shift hydraulic cylinder (12), the switching valves (S3) and (S4
) and (S2) operated by pressure oil,
Therefore, the valves (St), (TI), (T*), (T3) that control the operation of the clutch operation cylinder (13) are
Main gear transmission (Il+), forward and backward gear transmission f (H
Z) and the first auxiliary gear transmission (H3) are configured to be automatically switched in accordance with the gear shifting operation so as to be switched to the engaged operating position only in the transmission state.

但し、主ギヤ変速装置Y(H+)の2個の油圧シリンダ
(IOA) 、 (IOR)の一方を変速側に操作した
状態において、他方の油圧シリンダを変速中立位置に圧
油によって操作保持させるように構成しである。 又、
第2副ギヤ変速装置(H4)には、変速レバーにて操作
自在なシフターを付設してしる。 さらに、動力取出軸
(8)に対する変速装置(7)を人為的に操作するよう
に構成しである。
However, when one of the two hydraulic cylinders (IOA) and (IOR) of the main gear transmission Y (H+) is operated to the shifting side, the other hydraulic cylinder is operated and held in the shifting neutral position by pressure oil. It is composed of: or,
The second auxiliary gear transmission (H4) is provided with a shifter that can be operated using a gear shift lever. Furthermore, the transmission device (7) relative to the power take-off shaft (8) is configured to be manually operated.

主及び補助制御弁(Vl)、(V2)並びにクラッチ作
動制御の弁(s+)、 (T、)、 (’rz)、 (
Tりよりも流路上手側に、メインリリーフパルプ(15
)を付設すると共に、それからの排油潤滑のために油圧
クラッチ(C)に供給させるようしである。
Main and auxiliary control valves (Vl), (V2) and clutch actuation control valves (s+), (T,), ('rz), (
Main relief pulp (15
), and the oil is supplied to the hydraulic clutch (C) for lubrication of drained oil.

世し、図中、(N)及び(Fl)乃至(pe)の夫々は
、主制御弁(vl)の操作位置を示し、又、(F)及び
(R)は、補助制御弁(v2)の操作位置を示す。
In the figure, (N) and (Fl) to (pe) each indicate the operating position of the main control valve (vl), and (F) and (R) indicate the operating position of the auxiliary control valve (v2). Indicates the operating position.

第3図に示すように、圧油供給系統でクラッチ作動制御
弁(T3)と油圧クラッチ(C)との間には、電磁比例
減圧弁(17)が設けられており、その構造を第4図に
基づいて詳述すると、左右に揺動可能なスプール(18
)の一端側にソレノイドコイル(19)及び、他端側に
油圧ボー) (20P) 。
As shown in Fig. 3, an electromagnetic proportional pressure reducing valve (17) is provided between the clutch actuation control valve (T3) and the hydraulic clutch (C) in the pressure oil supply system, and its structure is shown in Fig. 4. To explain in detail based on the figure, the spool (18
) Solenoid coil (19) on one end side and hydraulic bow (20P) on the other end side.

(20C) 、 (20T)を形成するとともに、スプ
ール(18)の肉厚内に油圧ポート(20C)及びスプ
ール(18)先端側圧力室(21)とに連通可能な通路
(22)を形成し、もって、ソレノイドコイル(19)
によって押出力(P)を受けたスプール(18)の移動
によって、油圧ポート(20P) 、 (20C)が連
通状態になり、この連1tlll状態になることによっ
て、ポート(20P)からポート(20C)に圧油が供
給され、このポート(20C)に供給された圧油が通路
(22)を1fflって圧力室(21)に導入され、ス
プール(18)を前記押出力(F)に抗して、力(f)
で現状復帰させようとし、両者(F) 、 <f)がつ
り合った所でスプール(18)は静1卜し、ポート(2
0C)圧力が設定され、この設定された圧油が油圧クラ
ッチ(C)に送られることになる。 つまり、ソレノイ
ド(19)の励磁電圧に比例した圧力調整が可能である
(20C) and (20T), and a passage (22) that can communicate with the hydraulic port (20C) and the pressure chamber (21) on the tip side of the spool (18) is formed within the wall thickness of the spool (18). , with solenoid coil (19)
Due to the movement of the spool (18) which receives the pushing force (P), the hydraulic ports (20P) and (20C) are brought into communication. Pressure oil is supplied to this port (20C), and the pressure oil supplied to this port (20C) passes through the passage (22) by 1 ffl and is introduced into the pressure chamber (21), causing the spool (18) to resist the extrusion force (F). te, force (f)
When the two (F) and <f) are balanced, the spool (18) becomes static and the port (2
0C) pressure is set, and this set pressure oil is sent to the hydraulic clutch (C). In other words, the pressure can be adjusted in proportion to the excitation voltage of the solenoid (19).

この電磁比例減圧弁(17)に対して、この励磁電圧を
自動制御するマイコンを内臓した制御回路(23)を備
え、第1図に示すように、クラッチオン作動時における
前記減圧弁(17)への励磁電圧を、初期のものを大き
くして、油圧クラッチが作動する最低圧まで急速に昇圧
して無駄時間を抑えるとともに、以後の励磁電圧を初期
のものより低くして、それから徐々に大きな電圧のもの
にすることによって、昇圧カーブを緩やかなものにして
、円滑なりラッチ作動が得られるような方法をとってい
る。
The electromagnetic proportional pressure reducing valve (17) is equipped with a control circuit (23) containing a microcomputer that automatically controls the excitation voltage, and as shown in FIG. Increasing the initial excitation voltage for By using voltage, the voltage increase curve is made gentler, and smooth latch operation is achieved.

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

図面は本発明に係る油圧操作式ギヤ変速装置の油圧クラ
ッチ作動方法の実施例を示し、第1図は電磁比例減圧弁
への励磁電圧と油圧クラッチの昇圧特性を示すグラフ、
第2図はトラクタの駆動構造を示す構成図、第3図は油
圧クラッチへの油圧回路図、第4図は電磁比例減圧弁を
示す一部切欠側面図、第5図及び第6図は夫々、電磁比
例減圧弁への励磁電圧と油圧クラッチの昇圧特性の従来
例を示すグラフである。 (C)・・・・・・油圧クラッチ、(17)・・・・・
・電磁比例減圧弁。
The drawings show an embodiment of the hydraulic clutch actuation method for a hydraulically operated gear transmission according to the present invention, and FIG. 1 is a graph showing the excitation voltage to the electromagnetic proportional pressure reducing valve and the pressure increase characteristics of the hydraulic clutch.
Figure 2 is a configuration diagram showing the drive structure of the tractor, Figure 3 is a hydraulic circuit diagram for the hydraulic clutch, Figure 4 is a partially cutaway side view showing the electromagnetic proportional pressure reducing valve, Figures 5 and 6 are respectively , is a graph showing a conventional example of excitation voltage to an electromagnetic proportional pressure reducing valve and pressure increase characteristics of a hydraulic clutch. (C)...Hydraulic clutch, (17)...
・Solenoid proportional pressure reducing valve.

Claims (1)

【特許請求の範囲】[Claims]  変速用油圧クラッチ(C)への圧油供給系統に電磁比
例減圧弁(17)を設け、クラッチオン作動時における
前記減圧弁(17)への励磁電圧を、初期のものを大き
く、以後を初期励磁電圧よりも低い設定電圧から徐々に
大きくなるものに設定してクラッチの昇圧速度に対応さ
せてある油圧操作式ギヤ変速装置の油圧クラッチ作動方
法。
An electromagnetic proportional pressure reducing valve (17) is provided in the pressure oil supply system to the shift hydraulic clutch (C), and the excitation voltage to the pressure reducing valve (17) when the clutch is turned on is set to a high initial value and an initial high voltage thereafter. A hydraulic clutch operating method for a hydraulically operated gear transmission device in which a set voltage is gradually increased from a lower set voltage than an excitation voltage to correspond to a pressure increase speed of the clutch.
JP25604684A 1984-12-04 1984-12-04 Method of operating hydraulic clutch in hydraulically operated speed change gear unit Pending JPS61136044A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP25604684A JPS61136044A (en) 1984-12-04 1984-12-04 Method of operating hydraulic clutch in hydraulically operated speed change gear unit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP25604684A JPS61136044A (en) 1984-12-04 1984-12-04 Method of operating hydraulic clutch in hydraulically operated speed change gear unit

Publications (1)

Publication Number Publication Date
JPS61136044A true JPS61136044A (en) 1986-06-23

Family

ID=17287150

Family Applications (1)

Application Number Title Priority Date Filing Date
JP25604684A Pending JPS61136044A (en) 1984-12-04 1984-12-04 Method of operating hydraulic clutch in hydraulically operated speed change gear unit

Country Status (1)

Country Link
JP (1) JPS61136044A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2637036A1 (en) * 1988-09-29 1990-03-30 Kubota Ltd HYDRAULIC TRANSMISSION CONTROL APPARATUS
US4924983A (en) * 1987-12-10 1990-05-15 Kubota, Ltd. Propelling clutch apparatus for a working vehicle
US4979599A (en) * 1988-02-09 1990-12-25 Kubota, Ltd. Work vehicle
WO1999032809A2 (en) * 1997-12-19 1999-07-01 Zf Friedrichshafen Ag Gear shifting device

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4932488A (en) * 1972-07-24 1974-03-25
JPS596531B2 (en) * 1979-03-01 1984-02-13 島田理化工業株式会社 automatic frequency control device
JPS60256629A (en) * 1984-05-31 1985-12-18 Kawasaki Heavy Ind Ltd Hydraulic clutch cylinder control device

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4932488A (en) * 1972-07-24 1974-03-25
JPS596531B2 (en) * 1979-03-01 1984-02-13 島田理化工業株式会社 automatic frequency control device
JPS60256629A (en) * 1984-05-31 1985-12-18 Kawasaki Heavy Ind Ltd Hydraulic clutch cylinder control device

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4924983A (en) * 1987-12-10 1990-05-15 Kubota, Ltd. Propelling clutch apparatus for a working vehicle
US4979599A (en) * 1988-02-09 1990-12-25 Kubota, Ltd. Work vehicle
FR2637036A1 (en) * 1988-09-29 1990-03-30 Kubota Ltd HYDRAULIC TRANSMISSION CONTROL APPARATUS
WO1999032809A2 (en) * 1997-12-19 1999-07-01 Zf Friedrichshafen Ag Gear shifting device
WO1999032809A3 (en) * 1997-12-19 1999-10-07 Zahnradfabrik Friedrichshafen Gear shifting device
US6301984B1 (en) 1997-12-19 2001-10-16 Zf Friedrichshafen Ag Gear shifting device

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