JPH01156138A - Speed change gear of service car - Google Patents
Speed change gear of service carInfo
- Publication number
- JPH01156138A JPH01156138A JP62316868A JP31686887A JPH01156138A JP H01156138 A JPH01156138 A JP H01156138A JP 62316868 A JP62316868 A JP 62316868A JP 31686887 A JP31686887 A JP 31686887A JP H01156138 A JPH01156138 A JP H01156138A
- Authority
- JP
- Japan
- Prior art keywords
- cylinder
- hydraulic cylinder
- case
- spool
- swash plate
- 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
Links
- 230000005540 biological transmission Effects 0.000 claims abstract description 18
- 230000002706 hydrostatic effect Effects 0.000 claims description 8
- 238000006073 displacement reaction Methods 0.000 claims description 2
- 230000003068 static effect Effects 0.000 abstract 2
- 239000003921 oil Substances 0.000 description 8
- 239000010720 hydraulic oil Substances 0.000 description 7
- 230000007935 neutral effect Effects 0.000 description 3
- 230000002411 adverse Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000000994 depressogenic effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000011499 joint compound Substances 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は走行用として静油圧式無段変速装置を装備した
作業車において、その変速操作系の構造に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of a speed change operation system in a work vehicle equipped with a hydrostatic continuously variable transmission for traveling.
前述のように静油圧式無段変速装置（以下、Ｈ３Ｔと称
す）を装備した作業車においては、Ｈ３Ｔの斜板角度変
更用の操作軸と変速ペダルとをロッド等により直接機械
的に連動連結した機種が多くあるが、Ｈ３Ｔの斜板には
油圧ポンプの吐出反力により中立位置に復帰させようと
する力が作用する為、このカに抗して変速ペダルを操作
しなければならなくなり、その操作が比較的重いものと
なっている。そこで、変速ペダルの操作位置をポテンシ
ョメータ等により電気的検出して、この検出位置に基づ
いてモータによりＨ３Ｔの斜板角度を操作するように構
成した機種が提案されてきている。As mentioned above, in a work vehicle equipped with a hydrostatic continuously variable transmission (hereinafter referred to as H3T), the operating shaft for changing the swash plate angle of the H3T and the speed change pedal are directly mechanically interlocked by a rod or the like. However, the H3T's swash plate is subject to a force that attempts to return it to the neutral position due to the discharge reaction force of the hydraulic pump, so the shift pedal must be operated against this force. The operation is relatively heavy. Therefore, a model has been proposed in which the operating position of the speed change pedal is electrically detected by a potentiometer or the like, and the swash plate angle of the H3T is controlled by a motor based on this detected position.
農用トラクタ等の作業車では非舗装路や軟弱な圃場等の
悪条件下で走行して作業を行う為、足回りには泥や土及
び水等が付着し易い状態に在る。従って、このような悪
条件下において前述のような電気的な連係機構はその信
頼性及び耐久性が十分とは言い難く、作動不良の発生す
る確率が比較的高いと言ってよい。Since work vehicles such as agricultural tractors operate under adverse conditions such as unpaved roads and soft fields, their undercarriage is susceptible to mud, soil, water, and the like. Therefore, under such adverse conditions, the reliability and durability of the electrical linkage mechanism described above cannot be said to be sufficient, and the probability of malfunction occurring is relatively high.
ここで本発明は前述の状況に着目して成されたものであ
り、ＨＳＴの斜板の操作を軽く行える機構を信頼性及び
耐久性を有するものに構成することを目的としている。The present invention has been made in view of the above-mentioned situation, and it is an object of the present invention to provide a reliable and durable mechanism that allows the swash plate of an HST to be easily operated.
本発明の特徴は以上述べたような作業車の変速操作構造
を次のように構成することにある。The feature of the present invention is that the above-described shift operation structure for a work vehicle is configured as follows.
つまり、走行用の静油圧式無段変速装置における斜板角
度変更用の操作軸に対して油圧シリンダのシリンダケー
スを連動連結し、前記油圧シリンダのピストンロンドを
静油圧式無段変速装置のケーシングに連結固定すると共
に、前記油圧シリンダに対する制御弁をそのスプール軸
芯がシリンダ軸芯と平行となるように油圧シリンダのシ
リンダケースに固設し、且つ、前記制御弁のスプールと
人為操作具とを連動連結して、スプールの変位に対し油
圧シリンダのシリンダケースがフィードバンク追従変位
するように構成してあることにあり、その作用及び効果
は次のとおりである。That is, the cylinder case of a hydraulic cylinder is interlocked and connected to the operating shaft for changing the swash plate angle in a hydrostatic continuously variable transmission for traveling, and the piston rod of the hydraulic cylinder is connected to the casing of the hydrostatic continuously variable transmission. At the same time, a control valve for the hydraulic cylinder is fixed to the cylinder case of the hydraulic cylinder so that its spool axis is parallel to the cylinder axis, and the spool of the control valve and the human operating tool are connected to each other. The cylinder case of the hydraulic cylinder is connected in an interlocking manner so that the cylinder case of the hydraulic cylinder follows the feedbank in response to the displacement of the spool, and its functions and effects are as follows.
前述のように構成すると、人為操作具の操作により制御
弁のスプールが操作されると、これにより油圧シリンダ
内に作動油が給排操作されてスプールが操作される方向
に油圧シリンダのシリンダケースが追従して動いて行き
、ＨＳＴにおける斜板角度変更用の操作軸が操作されて
行くのである。With the configuration described above, when the spool of the control valve is operated by the manual operation tool, hydraulic oil is supplied and discharged into the hydraulic cylinder, and the cylinder case of the hydraulic cylinder is moved in the direction in which the spool is operated. It follows and moves, and the operating shaft for changing the swash plate angle in the HST is operated.
そして、油圧シリンダに対して制御弁が固定されて油圧
シリンダ及び制御弁が１つのユニット状になっているの
で、油圧シリンダのシリンダケースと斜板の操作軸との
連結部、ピストンロンドとＨＳＴのケーシングとの連結
部、制御弁のスプールと人為操作具との連結部及び油圧
配管を取り外すことによりＨＳＴから油圧シリンダ及び
制御弁のユニットを容易に取り外すことができるのであ
る。Since the control valve is fixed to the hydraulic cylinder and the hydraulic cylinder and control valve form one unit, the connecting part between the cylinder case of the hydraulic cylinder and the operation shaft of the swash plate, the piston rond and the HST. By removing the connecting portion to the casing, the connecting portion between the control valve spool and the human operating tool, and the hydraulic piping, the hydraulic cylinder and control valve unit can be easily removed from the HST.
以上のように、操作ペダル等の人為操作具とＨＳＴの操
作軸との連係構造を油圧式の連係構造とすることにより
、電気的な連係構造に比べて信頼性及び耐久性を向上さ
せることができた。As described above, by using a hydraulic linkage structure as the linkage structure between human operating tools such as operating pedals and the operating shaft of the HST, reliability and durability can be improved compared to electrical linkage structures. did it.
又、ＨＳＴの操作軸に対する油圧シリンダ及び制御弁を
１つのユニットとして簡単に着脱できるようになり、Ｈ
ＳＴの操作軸と人為操作具とを直接に連結した型式にも
比較的容易に変更できるようになる。In addition, the hydraulic cylinder and control valve can be easily attached to and detached from the HST operating shaft as a single unit.
It becomes possible to change relatively easily to a type in which the operating shaft of the ST and the human operating tool are directly connected.
以下、本発明の実施例の１つである農用トラクタについ
て図面に基づいて説明する。EMBODIMENT OF THE INVENTION Hereinafter, an agricultural tractor which is one of the embodiments of the present invention will be described based on the drawings.
第４図に示すように、前輪（１）及び後輪（２）で支持
された機体の前部にエンジン（３）、機体中央に操縦部
（４）、機体後部にミッションケース（５）が配置され
て四輪駆動型の農用トラクタが構成されている。As shown in Figure 4, the engine (3) is located at the front of the aircraft supported by the front wheels (1) and rear wheels (2), the control section (4) is located at the center of the aircraft, and the mission case (5) is located at the rear of the aircraft. A four-wheel drive agricultural tractor is constructed by the arrangement.
次に、前記ミッションケース（５）について詳述すると
第４図及び第１図に示すように、前輪変速装置（図示せ
ず）を内装する前ケース（５ａ）、 ゛静油圧
式無段変速装置（６）（以下、ＨＳＴと称す）を内装す
る中ケース（５ｂ）、ギヤ弐の副変速装置及びデフ機構
等（以上、図示せず）を内装する後ケース（５ｃ）が機
体前側から順に連結されてミッションケース（５）が構
成されている。Next, to explain the mission case (5) in detail, as shown in FIG. 4 and FIG. (6) The middle case (5b) containing the HST (hereinafter referred to as HST) and the rear case (5c) containing the second gear sub-transmission device, differential mechanism, etc. (not shown) are connected in order from the front side of the aircraft. A mission case (5) is constructed.
エンジン（３）からの動力は第１伝動軸（７）から中ケ
ース（５ｂ）内のＨＳ Ｔ （６）に伝達され、ＨＳ
Ｔ （６）から後ケース（５ｃ）内の副変速装置を介し
て後輪（２）へ伝達されると共に、前記副変速装置から
分岐した動力は前ケース（５ａ）内の前輪変速装置に伝
達され変速操作され、第２伝動軸（１３）を介して前輪
（１）に伝達されている。Power from the engine (3) is transmitted from the first transmission shaft (7) to the HS T (6) inside the middle case (5b),
T (6) is transmitted to the rear wheels (2) via the auxiliary transmission in the rear case (5c), and the power branched from the auxiliary transmission is transmitted to the front wheel transmission in the front case (5a). The transmission is then operated to change gears, and is transmitted to the front wheels (1) via the second transmission shaft (13).
次に前記ＨＳ Ｔ （６）の操作系の構造について詳述
すると第１図及び第３図に示すように、ＨＳ Ｔ （６
）の斜板（８）から横方向に操作軸（９）が突出しこの
操作軸（９）に板材を折り曲げた二股状の操作アーム（
１０）が取付けられている。この操作アーム（１０）に
対して油圧シリンダ（１１）が備えられているのである
が、この油圧シリンダ（１１）は同両図に示すように第
１油室（１２ａ）及び第２油室（１２ｂ）を備えたシリ
ンダケース（１２）と、ピストンロンド（１４）とから
構成されており、ピストンロンド（１４）の両端が前ケ
ース（５ａ）及び中ケース（５ｂ）の側壁部にボルト（
２４）で連結されると共に、シリンダケース（１２）の
表裏両側壁部の各々に２組ずつ設けられた凸部（１２ｃ
）の間に操作アーム（１０）の先端が挾まれるように挿
入されている。Next, the structure of the operation system of the HS T (6) will be described in detail. As shown in FIGS. 1 and 3, the HS T (6)
An operating shaft (9) protrudes laterally from the swash plate (8) of ), and a bifurcated operating arm (
10) is installed. A hydraulic cylinder (11) is provided for this operating arm (10), and this hydraulic cylinder (11) has a first oil chamber (12a) and a second oil chamber (12a) as shown in both figures. It consists of a cylinder case (12) with a piston rond (12b) and a piston rond (14), and both ends of the piston rond (14) are attached to the side walls of the front case (5a) and the middle case (5b) with bolts (
24), and two sets of protrusions (12c) are provided on each of the front and back side walls of the cylinder case (12).
) is inserted so that the tip of the operating arm (10) is sandwiched between the two.
さらに、前記シリンダケース（１２）の下部にはスプー
ル式の制御弁（１５）が、そのスプール（１６）の軸芯
方向とピストンロンド（１４）の軸芯方向とが平行とな
るように一体で形成されており、このスプール（１６）
と人為操作具（１７）としての変速ペダルとが連係機構
（１８）を介して機械的に連動連結されている。Further, a spool-type control valve (15) is integrally provided at the lower part of the cylinder case (12) so that the axial direction of the spool (16) and the axial direction of the piston rod (14) are parallel to each other. This spool (16)
and a speed change pedal serving as a human operating tool (17) are mechanically interlocked and connected via a linkage mechanism (18).
次に、変速ペダル（１７）と制御弁（１５）及び油圧シ
リンダ（１１）の動きについて述べると、第１図に示す
ようにＨＳ Ｔ （６）内の不足分の作動油を補給する
チャージポンプ（１９）から分岐した作動油は制御弁（
１５）のポンプボー１− （２０）に供給されている。Next, we will discuss the movements of the speed change pedal (17), control valve (15), and hydraulic cylinder (11).As shown in Figure 1, the charge pump replenishes the insufficient hydraulic oil in the HST (6). The hydraulic oil branched from (19) is supplied to the control valve (
15) is supplied to the pump bow 1- (20).
第１図は中立停止状態であるがこの状態から第２図に示
すように変速ペダル（１７）を前方に踏み込むと連係機
構（１８）を介して制御弁（１５）のスプール（１６）
が前方に引き出される。このような状態になるとポンプ
ボート（２０）と第１ボート（２１）とが連通してシリ
ンダケース（１２）の第１油室（１２ａ）に作動油が供
給されると共に、第２油室（１２ｂ）内の作動油が第２
ポート（２２）からドレンボート（２３）を介して排油
されて、シリンダケース（１２）及び制御弁（１５）が
第２図において右方向に移動して行き、操作軸（９）及
び斜板（８）が前進の増速側に操作されて行く。Fig. 1 shows the neutral stopped state, but from this state, as shown in Fig. 2, when the gear change pedal (17) is stepped forward, the spool (16) of the control valve (15) is activated via the linkage mechanism (18).
is pulled forward. In this state, the pump boat (20) and the first boat (21) communicate with each other, supplying hydraulic oil to the first oil chamber (12a) of the cylinder case (12), and supplying hydraulic oil to the second oil chamber (12a). 12b) is the second
The oil is drained from the port (22) via the drain boat (23), and the cylinder case (12) and control valve (15) move to the right in Fig. 2, and the operating shaft (9) and swash plate (8) is operated to the forward speed increasing side.
逆に、変速ペダル（１７）を後方に踏み込むとスプール
（１６）が制御弁（１５）内に押し込まれて、ポンプボ
ート（２０）と第２ポート（２２）とが連通状態となり
作動油がシリンダケース（１２）の第２油室（１２ｂ）
に供給されると共に、第１油室（１２ａ）内の作動油は
第１ボート（２１）からスプーノ喧１６）の内部油路（
１６ａ）及びドレンボー） （２３）を介して排油され
て行く。これにより、シリンダケース（１２）及び制′
４１１弁（１５）が第１図において左方向に移動して行
き、操作軸（９）及び斜板（８）が後進の増速側に操作
されて行くのである。Conversely, when the speed change pedal (17) is stepped backward, the spool (16) is pushed into the control valve (15), the pump boat (20) and the second port (22) are in communication, and the hydraulic oil is pumped into the cylinder. Second oil chamber (12b) of case (12)
At the same time, the hydraulic oil in the first oil chamber (12a) is supplied from the first boat (21) to the internal oil passage (
16a) and Dorenbo) (23). This allows the cylinder case (12) and the
The 411 valve (15) moves to the left in FIG. 1, and the operating shaft (9) and swash plate (8) are operated to increase the speed of reverse travel.
以上の構造によって、油圧シリンダ（１１）のピストン
ロンド（１４）を前ケース（５ａ）及び中ケース（５ｂ
）に連結しているポル！−（２４）を外すと共に、制御
弁（１５）のスプール（１６）と連係機構（１８）との
連結を外し、制御弁（１５）のポンプボー１− （２０
）及びドレンボート（２３）に連結されている配管（２
５）。With the above structure, the piston rond (14) of the hydraulic cylinder (11) is connected to the front case (5a) and the middle case (5b).
) connected to Pol! - (24), and also disconnect the spool (16) of the control valve (15) from the linkage mechanism (18).
) and the pipe (2) connected to the drain boat (23)
5).
（２６）を外すことにより、油圧シリンダ（１１）及び
制御弁（１５）を取り外すことができるのである。By removing (26), the hydraulic cylinder (11) and control valve (15) can be removed.
尚、特許請求の範囲の項に図面との対照を便利にする為
に符号を記すが、該記入により本発明は添付図面の構造
に限定されるものではない。Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.
図面は本発明に係る作業車の変速操作構造の実施例を示
し、第１図は中立停止状態での油圧シリンダ及び制御弁
の構造を示す断面図、第２図は第１図に示す状態から変
速ペダルを前方に踏み込んだ場合の油圧シリンダ及び制
御弁の状態を示す断面図、第３図は静油圧式無段変速装
置における斜板付近の縦断正面図、第４図は農用トラク
タの全体側面図である。
（５）・・・・・・ケーシング、（６）・・・・・・静
油圧式無段変速装置、（９）・・・・・・操作軸、（１
１）・・・・・・油圧シリンダ、（１２）・・・・・・
シリンダケース、（１４）・・・・・・ピストンロンド
、（１５）・・・・・・制御弁、（１６）・・・・・・
スプール。The drawings show an embodiment of the speed change operation structure for a work vehicle according to the present invention, FIG. 1 is a sectional view showing the structure of the hydraulic cylinder and control valve in a neutral stopped state, and FIG. A cross-sectional view showing the state of the hydraulic cylinder and control valve when the speed change pedal is depressed forward, Fig. 3 is a vertical cross-sectional front view of the vicinity of the swash plate in the hydrostatic continuously variable transmission, and Fig. 4 is an overall side view of the agricultural tractor. It is a diagram. (5)...Casing, (6)...Hydrostatic continuously variable transmission, (9)...Operation shaft, (1
1)...Hydraulic cylinder, (12)...
Cylinder case, (14)... Piston rond, (15)... Control valve, (16)...
spool.
Claims (1)
変更用の操作軸（９）に対して油圧シリンダ（１１）の
シリンダケース（１２）を連動連結し、前記油圧シリン
ダ（１１）のピストンロッド（１４）を静油圧式無段変
速装置（６）のケーシング（５）に連結固定すると共に
、前記油圧シリンダ（１１）に対する制御弁（１５）を
そのスプール軸芯がシリンダ軸芯と平行となるように油
圧シリンダ（１１）のシリンダケース（１２）に固設し
、且つ、前記制御弁（１５）のスプール（１６）と人為
操作具（１７）とを連動連結して、スプール（１６）の
変位に対し油圧シリンダ（１１）のシリンダケース（１
２）がフィードバック追従変位するように構成してある
作業車の変速操作構造。A cylinder case (12) of a hydraulic cylinder (11) is interlocked and connected to an operating shaft (9) for changing the swash plate angle in a hydrostatic continuously variable transmission (6) for traveling, and the hydraulic cylinder (11) The piston rod (14) is connected and fixed to the casing (5) of the hydrostatic continuously variable transmission (6), and the control valve (15) for the hydraulic cylinder (11) is connected so that its spool axis is aligned with the cylinder axis. The spool (16) of the control valve (15) is fixed to the cylinder case (12) of the hydraulic cylinder (11) so as to be parallel to each other, and the spool (16) of the control valve (15) and the human operating tool (17) are interlocked. The cylinder case (1) of the hydraulic cylinder (11)
2) A speed change operation structure for a working vehicle configured to perform feedback-following displacement.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62316868A JPH06100278B2 (en) | 1987-12-15 | 1987-12-15 | Shifting structure of work vehicle |
| US07/281,716 US4977760A (en) | 1987-12-15 | 1988-12-09 | Speed control system for a working vehicle |
| KR1019880016723A KR910004564B1 (en) | 1987-12-15 | 1988-12-15 | Speed control system for a working vehicle |
| DE3842291A DE3842291A1 (en) | 1987-12-15 | 1988-12-15 | DRIVE CONTROL DEVICE FOR A WORK VEHICLE |
| FR8816544A FR2624449B1 (en) | 1987-12-15 | 1988-12-15 | SPEED CONTROL DEVICE FOR A UTILITY VEHICLE, PARTICULARLY FOR AN AGRICULTURAL TRACTOR |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62316868A JPH06100278B2 (en) | 1987-12-15 | 1987-12-15 | Shifting structure of work vehicle |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01156138A true JPH01156138A (en) | 1989-06-19 |
| JPH06100278B2 JPH06100278B2 (en) | 1994-12-12 |
Family
ID=18081807
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62316868A Expired - Lifetime JPH06100278B2 (en) | 1987-12-15 | 1987-12-15 | Shifting structure of work vehicle |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH06100278B2 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100300436B1 (en) * | 1997-09-18 | 2001-09-06 | 미쯔이 고오헤이 | Working vehicle |
| JP2016038054A (en) * | 2014-08-08 | 2016-03-22 | 株式会社 神崎高級工機製作所 | Servo mechanism for controlling volume of hydraulic shift device |
| US10641389B2 (en) | 2014-08-07 | 2020-05-05 | Kanzaki Kokyukoki Mfg. Co., Ltd. | Actuator unit for controlling hydraulic pump |
| US10794480B2 (en) | 2014-08-07 | 2020-10-06 | Kanzaki Kokyukoki Mfg. Co., Ltd. | Control mechanism for stepless transmission |
| US10890252B2 (en) | 2014-08-07 | 2021-01-12 | Kanzaki Kokyukoki Mfg. Co., Ltd. | Control mechanism for stepless transmission |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS531529A (en) * | 1976-06-25 | 1978-01-09 | Durst Ag | Meter for deciding color montage of photographic enlarger copy light |
-
1987
- 1987-12-15 JP JP62316868A patent/JPH06100278B2/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS531529A (en) * | 1976-06-25 | 1978-01-09 | Durst Ag | Meter for deciding color montage of photographic enlarger copy light |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100300436B1 (en) * | 1997-09-18 | 2001-09-06 | 미쯔이 고오헤이 | Working vehicle |
| US10641389B2 (en) | 2014-08-07 | 2020-05-05 | Kanzaki Kokyukoki Mfg. Co., Ltd. | Actuator unit for controlling hydraulic pump |
| US10794480B2 (en) | 2014-08-07 | 2020-10-06 | Kanzaki Kokyukoki Mfg. Co., Ltd. | Control mechanism for stepless transmission |
| US10890252B2 (en) | 2014-08-07 | 2021-01-12 | Kanzaki Kokyukoki Mfg. Co., Ltd. | Control mechanism for stepless transmission |
| JP2016038054A (en) * | 2014-08-08 | 2016-03-22 | 株式会社 神崎高級工機製作所 | Servo mechanism for controlling volume of hydraulic shift device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06100278B2 (en) | 1994-12-12 |
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