JPS616028A - Control circuit for hydraulic clutch for running speed shift - Google Patents

Control circuit for hydraulic clutch for running speed shift

Info

Publication number
JPS616028A
JPS616028A JP59126870A JP12687084A JPS616028A JP S616028 A JPS616028 A JP S616028A JP 59126870 A JP59126870 A JP 59126870A JP 12687084 A JP12687084 A JP 12687084A JP S616028 A JPS616028 A JP S616028A
Authority
JP
Japan
Prior art keywords
pressure
valve
clutch
set value
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.)
Granted
Application number
JP59126870A
Other languages
Japanese (ja)
Other versions
JPH045852B2 (en
Inventor
Satoru Fukui
福井 哲
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 JP59126870A priority Critical patent/JPS616028A/en
Publication of JPS616028A publication Critical patent/JPS616028A/en
Publication of JPH045852B2 publication Critical patent/JPH045852B2/ja
Granted legal-status Critical Current

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16DCOUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D25/00Fluid-actuated clutches
    • F16D25/12Details not specific to one of the before-mentioned types
    • F16D25/14Fluid pressure control
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16DCOUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D48/00External control of clutches
    • F16D48/02Control by fluid pressure
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16DCOUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D48/00External control of clutches
    • F16D48/02Control by fluid pressure
    • F16D2048/0209Control by fluid pressure characterised by fluid valves having control pistons, e.g. spools

Abstract

PURPOSE:To make a loss time short, by disposing, in parallel, a valve which closes when a secondary pressure exceeds a set value, a valve which opens when the secondary pressure is below the set value and an orifice between a hydraulic pump and a speed shift hydraulic clutch. CONSTITUTION:A valve 18 which closes when a secondary pressure exceeds a set value P1, a valve 19 which opens when the secondary pressure is at a set value P2 higher than the above-mentioned set value P1 and an orifice 20 are connected in parallel together between a pump P and a speed shift hydraulic clutch C in a passage upstream of clutch operation control valves T1 through T4. Accordingly, the valve 18 opens when the secondary pressure is below the set value P1 to boost up the pressure up to the initial operating pressure of the hydraulic clutch C in a short time. Both valves 18, 19 close when the secondary pressure is between both set pressures P1, P2, and therefore the pressure is gradually raised by means of the orifice 20 to offer a smooth clutch operating characteristic. Further, when the secondary pressure exceeds the set value P2, the valve 19 opens to rapidly boost up the pressure up to the set pressure value of a valve 15 to give the normal clutch transmission condition.

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ツツチメ油圧ボンプメ間の圧油供
給路に漸次外圧機構を装備して、円滑なりラッチ作動を
得られるように構成してある走行変速用油圧クラッチ操
作回路に関する・〔従来の技術〕 従来は、漸次外圧機構としてオリフィスを油圧ポンプと
変速用油圧クラッチとの間に接続してあった。 従って
、この場合には第5図に示すように、油圧クラッチでの
外圧特性が零圧から等勾配で昇圧する特性のものであっ
た。
[Detailed Description of the Invention] [Field of Industrial Application] The present invention is structured so that a gradual external pressure mechanism is installed in a pressure oil supply path between a gear shift hydraulic pump and a hydraulic pump to obtain a smooth latch operation. Concerning a Hydraulic Clutch Operation Circuit for Traveling Transmission [Prior Art] Conventionally, an orifice has been connected between a hydraulic pump and a hydraulic clutch for transmission as a gradual external pressure mechanism. Therefore, in this case, as shown in FIG. 5, the external pressure characteristics of the hydraulic clutch were such that the pressure increased from zero pressure at a constant gradient.

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

しかし乍ら、クラッチはある一定圧(Po)以上になら
ないとトルク伝達を開始しない特性のものであるから、
図示するように圧力(Pa)に昇圧するまではクラッチ
が継がない無駄時間(to)になっていた。
However, since the clutch has a characteristic that it does not start transmitting torque until it reaches a certain pressure (Po),
As shown in the figure, there is a dead time (to) in which the clutch does not engage until the pressure is increased to (Pa).

本発明の目的は、オリフィスを有効利用し乍ら、他の機
構の追加構成によって、無駄時間が短かく、かつ望まし
いクラッチ作動特性が得られるものを提供する点にある
It is an object of the present invention to provide a clutch that effectively utilizes the orifice while reducing dead time and providing desirable clutch operating characteristics by adding other mechanisms.

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

本発明による特徴構成は油圧ポンプと変速用や 油圧クラッチとの間に、二次側圧力が定値以上で閉じる
パルプと、二次側圧力が、前記一定値よりも高い一定値
で開くパルプと、オリフィスとを並列に接続してある点
にあシ、その作用効果は次の通りである。
The characteristic configuration according to the present invention includes a pulp that closes when the secondary pressure is above a certain value and a pulp that opens when the secondary side pressure is a certain value higher than the certain value, between the hydraulic pump and the speed change or hydraulic clutch. The effect of connecting the orifice in parallel is as follows.

〔作 用〕[For production]

つまり、第4図に示すように一定圧(P1)を油圧クラ
ッチが作動を開始する最低圧(Po)に設定して、圧油
をこのバルブを通して油圧クラッチに送り込むことによ
って、短時間に油圧クラッチ作動圧(P1)を得ること
ができる。 しかも、一定圧(PI)を越えた状態から
一定圧(Po) tでの間は両バルブが閉状態にあるの
で、圧油はオリフィスを湧して供給され、油圧クラッチ
圧が漸次昇圧して円滑なりラッチ作動が行なわれるとと
もに、一定圧(Pりを越えた状態では他方のバルブが開
になるので、圧油はこのバルブを通して供給され、短時
間に所定の作動圧まで昇圧されて、油圧クラッチとして
の所期の継がシ状態を得る。
In other words, as shown in Fig. 4, by setting a constant pressure (P1) to the lowest pressure (Po) at which the hydraulic clutch starts operating, and sending pressure oil to the hydraulic clutch through this valve, the hydraulic clutch can be activated in a short time. Working pressure (P1) can be obtained. Moreover, since both valves are closed from the state exceeding the constant pressure (PI) to the constant pressure (Po) t, pressurized oil is supplied through the orifice, and the hydraulic clutch pressure gradually increases. In addition to smooth latch operation, the other valve opens when the pressure exceeds a certain pressure (P), so pressurized oil is supplied through this valve, and the pressure is increased to the predetermined operating pressure in a short time, increasing the hydraulic pressure. The desired clutch state is achieved as a clutch.

従って、オリフィスと作動特性の異なるバルブを並列に
接続する機構付加によって、バルブの作動圧の合理的な
設定とオリフィスの絞り効果を有効利用して、無駄時間
の少ない、円滑な作動特性が得られた。
Therefore, by adding a mechanism that connects orifices and valves with different operating characteristics in parallel, it is possible to rationally set the valve's operating pressure and effectively utilize the orifice's throttling effect, resulting in smooth operating characteristics with less wasted time. Ta.

〔発明の効果〕〔Effect of the invention〕

油圧クラッチの望ましい作動特性を得るに、バルブを付
加構成するだけの機構付加によるだけで、マイコン等を
併用した複雑な制御機構を要することなく、機器構成上
を安価なものを提供できるに至った。
In order to obtain the desired operating characteristics of a hydraulic clutch, it is possible to provide an inexpensive device configuration by simply adding a mechanism by adding a valve, without requiring a complex control mechanism using a microcomputer, etc. .

〔実施例〕〔Example〕

第2図はトフクタに装備のミッションケース(財)内の
伝動構造を示し、エンジン(EI K連動連結させた入
力軸+1)と走行用第1伝動軸(T1とに亘って、を段
切換自在なシンクロメツシュ式主ギヤ変速装置(U1)
を設け、第1伝動軸(2)と走行用第2伝動軸(3)と
の間に、摩擦板式変速用油圧クラッチ((2)を設け、
第2伝動軸(3)の出力を正逆転変速するシンクロメツ
シュ式前後進ギヤ変速装置(Hり、それをらの出力を高
低2段に切換自在なシンクロメツシュ式第1副ギヤ変速
装置(H3)、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(亀)の夫々を設け、そして
、第2副ギヤ変速装置(H6)の出力を後輪(4)の差
動機構(4A)、及び、前輪(5)の差動機構(5A)
に伝動させるように構成してある。
Figure 2 shows the transmission structure inside the mission case equipped on the TOFUKUTA. Synchronized main gear transmission (U1)
A friction plate type transmission hydraulic clutch ((2) is provided between the first transmission shaft (2) and the second driving transmission shaft (3),
A synchromesh type forward/reverse gear transmission that changes the output of the second transmission shaft (3) in forward and reverse directions. (H3) and a second auxiliary gear transmission (tortoise) that can freely switch the output from the second gear transmission into two high and low stages, and the output of the second auxiliary gear transmission (H6) is transferred to the rear wheel (4). differential mechanism (4A) and front wheel (5) differential mechanism (5A)
It is configured to transmit power to the

前記入力軸t1)の動力を1段に変速して動力取出用伝
動軸(6)に伝動するシンクロメツ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、中継伝動軸(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てある。
A synchromesh type gear transmission (7) is provided that shifts the power of the input shaft (t1) to one stage and transmits it to the power extraction transmission shaft (6), and also includes a synchromesh type gear transmission (7) that shifts the power of the input shaft (t1) to one stage and transmits it to the power extraction transmission shaft (6).
) is provided with a relay transmission shaft (9), so that the speed of the power take-off shaft (8) can be changed.

次に1走行用伝動系に対する変速操作構造について、第
1図乃至第4図に基づいて詳述する。
Next, the gear change operation structure for the one-travel transmission system will be described in detail with reference to FIGS. 1 to 4.

すなわち、主ギヤ変速装置(H1)に、択一的に作動さ
れる変速シフター操作用油圧シリンダ(IOA)、(I
OB)の−個を付設すると共に、第1副ギヤ変速装置(
Hs )に、変速シフター操作用油圧シリンダ02の7
個を付設し、そして、前記油圧クラッチ(C)に、入シ
操作用の油圧シリンダ+1&を付設してある。
That is, the main gear transmission (H1) is provided with a hydraulic cylinder (IOA) for operating a gear shifter (IOA), which is selectively operated.
OB), and a first auxiliary gear transmission (OB).
Hs), hydraulic cylinder 02-7 for gear shifter operation
The hydraulic clutch (C) is also provided with a hydraulic cylinder +1& for engaging operation.

前記主ギヤ変速用油圧シリンダ(IOA) 、(IOB
)及び前記第1副変速用油圧シリンダ112夫々に対す
る主制御弁(v1)、並びに、スブーμにシフトフォー
クを一体駆動可能に装備した前記前後進変速用補助制御
弁(v2)を、油圧ポンプ田)に並列接続してある・ 
そして、前記各油圧シリンダCl0A)・・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
(8り、(86) 、(84)の3個を構成し、ポンプ
fP)からの圧油をクラッチ操作用油圧シリンダ03に
供給する油路−を設けると共に、その油路−を開閉する
ためのパイロット圧操作式切換弁(T1)、(T鵞)、
(TI)、(T6)のφ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(IOA)、(IOE
)及び第1副変速用油圧シリンダ(12の夫々にて構成
した切襖弁(Sm)、(8県)、(S禦)及び補助制御
弁(Vり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a31の作動を制御する弁(
T1) 。
The main gear shifting hydraulic cylinder (IOA), (IOB
) and the main control valve (v1) for each of the first auxiliary transmission hydraulic cylinders 112, and the auxiliary control valve (v2) for forward and backward transmission, which is equipped to drive the shift fork integrally with the subu μ, are connected to the hydraulic pump field. ) are connected in parallel to
Then, the pistons of each of the hydraulic cylinders Cl0A) are used also as sliding spools, and the pressure from the 3-position switching valves (comprising three of 8ri, (86), and (84), pump fP) is An oil passage for supplying oil to the clutch operation hydraulic cylinder 03 is provided, and a pilot pressure operated switching valve (T1), (T鵞), for opening and closing the oil passage.
When (TI) and (T6) φ pieces are arranged in series,
In addition, the main gear shifting hydraulic cylinder (IOA), (IOE
) and the first auxiliary transmission hydraulic cylinder (sliding valves (Sm), (8 prefectures), (Sm), each consisting of 12 valves, and auxiliary control valves (operated with pressure oil from the V valve). A valve (
T1).

(T寓)、(Ts)、(%”)  を、主ギヤ変速装置
(Ht)、前後進ギヤ変速装置(Ha)、及び、第1副
ギヤ変速装置(H3)の伝動状態においてのみ入シ操作
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てある。
(T), (Ts), (%'') are input only in the transmission state of the main gear transmission (Ht), forward/reverse gear transmission (Ha), and first auxiliary gear transmission (H3). In order to switch to the operating position, the switching operation is automatically performed in conjunction with the gear shifting operation.

但し、主ギヤ変速装置(H1)の2個の油圧シリンダ(
IOA)、(IOB)の−力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てある。 又、第2副
ギヤy速装置(現)Kは、変速レバーにて操作自在なシ
フターを付設してある。 さらに、動力取出軸(8)に
対する変速装置(7)は、人為的にシフト操作するよう
に構成してある。
However, the two hydraulic cylinders (
When the forces of IOA) and (IOB) are operated toward the shift side, the other hydraulic cylinder is operated and held at the shift neutral position by pressure oil. Further, the second auxiliary gear y-speed device (currently) K is equipped with a shifter that can be freely operated with a speed change lever. Furthermore, the transmission (7) for the power take-off shaft (8) is configured to be manually shifted.

主及び補助制御弁(V2 ) 、 (V! )並びにク
ラッチ作動制御の弁(TI)、(Tり、(Tす、(Ta
)よシも流路上手側に二次側圧力が一定圧以上で賄じる
油圧クラッチ+01用リデユーシングバルブomを付設
スると共に、作業機側昇降シリンダ(lliへの圧油経
路内に介装された、−次側圧力が一定圧以上で開く昇降
シリンダ(11)用リデューシングバルプQ−と前記り
デューシングバルプ(lI5)とで油圧クラッチ(@及
び昇降シリンダ(lliに夫々の作動圧に設定された圧
油を供給制御するように構成するとともに、従来リリー
フ弁によって、油圧タンクに還流させていた圧油を帰還
させるととカく、設定圧に応じて有効利用できる。 更
に、両バpグθの、傾はポンプ史)に併設されたフィル
タ07)プラケット(17A)内に内装されているので
、配置スペース上かつ、配管施工上有利である。
Main and auxiliary control valves (V2), (V!) and clutch actuation control valves (TI), (Tri, (Tsu, (Ta)
) Also, a reducing valve om for the hydraulic clutch +01 is installed on the upstream side of the flow path to ensure that the secondary side pressure is above a certain pressure, and a reducing valve om for the hydraulic clutch +01 is installed on the upstream side of the flow path, and a The interposed reducing valve Q- for the lifting cylinder (11), which opens when the downstream pressure exceeds a certain pressure, and the above-mentioned reducing valve (lI5) actuate the hydraulic clutch (@ and the lifting cylinder (lli), respectively. In addition to controlling the supply of pressure oil set at a pressure, the pressure oil that was conventionally returned to the hydraulic tank is returned to the hydraulic tank using a relief valve, so that it can be used effectively according to the set pressure.Furthermore, Since both bags θ are installed inside the filter 07) placket (17A) attached to the filter 07), it is advantageous in terms of installation space and piping construction.

前記リデューシングバルプQ[ilとパイロット圧操作
式切換弁(T1)との間の圧油経路内には、二次側圧力
が一定値(P1)以上で閉じるバルブ11111と二次
側圧力が前記一定値(PI)よりも高い一定値(P2)
で開くバルブ(I(至)と、オリフィス穴とが並列に接
続してあり、もって、一定値(Pi)よシ低い圧力では
圧油はパルプ霞を通過して、短時間で油圧クラッチ+0
1の初期作動圧に外圧され、一定値(P1)より一定値
(P2)までの間では圧油は両パルプH、ati+が閉
じ状態にあるのでオリフィスを通過すること罠なり、円
滑なりラッチ特性が得られるように漸次昇圧され、一定
値(P宜)以上ではパルプ(イ)が開状態になり、圧油
が前記油圧クラッチ(Q側すデューシングバルグ0荀の
設定圧力まで急激に昇圧され、通常の油圧クラッチte
l伝動状態を現出する。
In the pressure oil path between the reducing valve Q[il and the pilot pressure operated switching valve (T1), there is a valve 11111 that closes when the secondary pressure is above a certain value (P1) and a valve 11111 that closes when the secondary pressure is above a certain value (P1). Constant value (P2) higher than constant value (PI)
The valve (I (to)) that opens at 100°C and the orifice hole are connected in parallel, so that at pressures lower than a certain value (Pi), the pressure oil passes through the pulp haze and the hydraulic clutch +0 is reached in a short time.
The external pressure is applied to the initial operating pressure of 1, and between the constant value (P1) and the constant value (P2), the pressure oil passes through the orifice because both pulps H and ati+ are closed, and the latch characteristic is smooth. The pressure is gradually increased so as to obtain a pressure of , ordinary hydraulic clutch te
l Express the transmission state.

〔別実施例〕[Another example]

上記実施例のものはトフクタ以外の農用作簿車に適用し
てもよい。
The above embodiments may be applied to agricultural ledger vehicles other than Tofukuta.

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

図面は本発明に係る走行変速用油圧クラッチ操作回路の
実施例を示し、第1図は油圧クラッチへの油圧回路図、
第2図は走行駆動系の構成図、第3図は油圧ポンプの取
付状態を示す側面図、第4図は油圧クラッチの作動圧特
性を示すグラフ、第5図は従来の油圧クラッチの作動圧
特性を示すグラフである。 (1〜、09)・・・・・・パルプ、吹・・・・・・オ
リフィス、(P)・・・・・・油圧ポンプ、(P1)、
(Pm)・・・・・・一定圧。 代理人  弁理士  北  村     修1<
The drawings show an embodiment of the hydraulic clutch operation circuit for traveling speed change according to the present invention, and FIG. 1 is a hydraulic circuit diagram for the hydraulic clutch;
Figure 2 is a configuration diagram of the travel drive system, Figure 3 is a side view showing how the hydraulic pump is installed, Figure 4 is a graph showing the operating pressure characteristics of the hydraulic clutch, and Figure 5 is the operating pressure of a conventional hydraulic clutch. It is a graph showing characteristics. (1~,09)...Pulp, blowing...orifice, (P)...hydraulic pump, (P1),
(Pm)...Constant pressure. Agent Patent Attorney Osamu Kitamura1<

Claims (1)

【特許請求の範囲】[Claims] 油圧ポンプ(P)と変速用油圧クラッチ(C)との間に
、二次側圧力が一定値(P_1)以上で閉じるパルプ(
18)と、二次側圧力が、前記一定値(P_1)よりも
高い一定値(P_2)で開くバルブ(19)と、オリフ
イス(20)とを並列に接続してある走行変速用油圧ク
ラッチ操作回路。
Between the hydraulic pump (P) and the hydraulic clutch for speed change (C), there is a pulp (
18), a valve (19) that opens at a constant value (P_2) where the secondary side pressure is higher than the above-mentioned constant value (P_1), and an orifice (20) are connected in parallel. circuit.
JP59126870A 1984-06-20 1984-06-20 Control circuit for hydraulic clutch for running speed shift Granted JPS616028A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP59126870A JPS616028A (en) 1984-06-20 1984-06-20 Control circuit for hydraulic clutch for running speed shift

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP59126870A JPS616028A (en) 1984-06-20 1984-06-20 Control circuit for hydraulic clutch for running speed shift

Publications (2)

Publication Number Publication Date
JPS616028A true JPS616028A (en) 1986-01-11
JPH045852B2 JPH045852B2 (en) 1992-02-03

Family

ID=14945872

Family Applications (1)

Application Number Title Priority Date Filing Date
JP59126870A Granted JPS616028A (en) 1984-06-20 1984-06-20 Control circuit for hydraulic clutch for running speed shift

Country Status (1)

Country Link
JP (1) JPS616028A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63151574A (en) * 1986-12-16 1988-06-24 Kubota Ltd Hydraulic circuit for working vehicle
JPS63152751A (en) * 1986-12-17 1988-06-25 Kubota Ltd Hydraulically operated gear transmission

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5437061U (en) * 1977-08-18 1979-03-10

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5437061U (en) * 1977-08-18 1979-03-10

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63151574A (en) * 1986-12-16 1988-06-24 Kubota Ltd Hydraulic circuit for working vehicle
JPS63152751A (en) * 1986-12-17 1988-06-25 Kubota Ltd Hydraulically operated gear transmission

Also Published As

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JPH045852B2 (en) 1992-02-03

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