JP2009063083A - Work vehicle - Google Patents

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JP2009063083A
JP2009063083A JP2007231486A JP2007231486A JP2009063083A JP 2009063083 A JP2009063083 A JP 2009063083A JP 2007231486 A JP2007231486 A JP 2007231486A JP 2007231486 A JP2007231486 A JP 2007231486A JP 2009063083 A JP2009063083 A JP 2009063083A
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left brake
operated
brake pedals
continuously variable
variable transmission
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JP5123617B2 (en
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Susumu Umemoto
享 梅本
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Kubota Corp
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Kubota Corp
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Abstract

<P>PROBLEM TO BE SOLVED: To improve controllability at small turning, while operating a continuously variable transmission from a high-speed side to a stop position side, when right and left brake pedals are depressed at straight-ahead traveling and operated to a braking side in a work vehicle. <P>SOLUTION: When the right and left brake pedals 15, 16 are depressed while the operating positions of the right and left brake pedals 15, 16 are same, the continuously variable transmission 5 for traveling is operated to the stop position N side. When the right and left brake pedals 15, 16 are depressed while the operating positions of the right and left brake pedals 15, 16 are different, as the operating positions of the right or left brake pedals 15, 16 on a near side to a depressing operation releasing position A1 comes close to a braking side limit position A2, the continuously variable transmission 5 for traveling is operated to the stop position N side. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明は、人為的に操作される右及び左のブレーキペダルと、右及び左の走行装置用の右及び左のブレーキとを備えた作業車に関する。   The present invention relates to a work vehicle including artificially operated right and left brake pedals and right and left brakes for right and left traveling devices.

作業車では、特許文献１に開示されているように、人為的に操作される右及び左のブレーキペダル（特許文献１の図１，６，７のＢＰＲ，ＢＰＬ）、右及び左の後輪（走行装置に相当）（特許文献１の図１の２）用の右及び左のブレーキを備えて、右のブレーキペダルが踏み操作されると連係機構を介して右のブレーキが制動側に操作され、左のブレーキペダルが踏み操作されると連係機構を介して左のブレーキが制動側に操作されるように構成しているものが多くある。
直進時の停止時には、運転者が右及び左のブレーキペダルを踏み操作し、右及び左のブレーキを制動側に操作して、機体を停止させる。例えば右に旋回する場合、運転者が前輪を右に操向操作すると同時に右のブレーキペダルを踏み操作し、右のブレーキを制動側に操作することにより、右への小回り旋回を行うことができる。 In the work vehicle, as disclosed in Patent Document 1, the right and left brake pedals (BPR and BPL in FIGS. 1, 6, and 7 in Patent Document 1), the right and left rear wheels, which are artificially operated. (Equivalent to traveling device) (2 in FIG. 1 of Patent Document 1) With right and left brakes, when the right brake pedal is depressed, the right brake is operated to the braking side via the linkage mechanism In many cases, the left brake is operated to the brake side via a linkage mechanism when the left brake pedal is depressed.
When stopping straight, the driver depresses the right and left brake pedals and operates the right and left brakes to the braking side to stop the aircraft. For example, when turning to the right, the driver can steer the front wheel to the right and simultaneously depress the right brake pedal and operate the right brake to the braking side to make a small turn to the right. .

停止位置から高速側に操作自在な走行用の無段変速装置（特許文献１の図１及び図２の７）を備えた場合、直進時に運転者が右及び左のブレーキペダルを踏み操作して、右及び左のブレーキが制動側に操作されると、走行用の無段変速装置が高速側から中立位置（停止位置）側に操作されるように構成されたものが多くある。これにより、走行用の無段変速装置が高速側に操作された状態で、右及び左のブレーキの制動力が発生する状態を防止しており、右及び左のブレーキへの負担を軽くしている。   When a continuously variable transmission for traveling (7 in FIG. 1 and FIG. 2 of Patent Document 1) that can be operated from the stop position to the high speed side is provided, the driver depresses the right and left brake pedals when going straight ahead. In many cases, when the right and left brakes are operated to the braking side, the continuously variable transmission for traveling is operated from the high speed side to the neutral position (stop position) side. This prevents the braking force of the right and left brakes from being generated when the continuously variable transmission for driving is operated to the high speed side, and reduces the burden on the right and left brakes. Yes.

特許文献１では、走行用の無段変速装置を操作する変速ペダル（特許文献１の図１及び図２の９）、変速ペダルを高速側に踏み操作した状態で保持可能なリンク（特許文献１の図５の２０）、及びノッチレバー（特許文献１の図５の２１）が備えられており、運転者が右及び左のブレーキペダルを踏み操作すると、ノッチレバーがリンクから離し操作されて変速ペダルの保持が解除され、中立装置（特許文献１の図２の１０）により、変速ペダル及び走行用の無段変速装置が中立位置（停止位置）側に操作されるように構成されている。   In Patent Document 1, a shift pedal (9 in Patent Document 1 and FIG. 2 in FIG. 2) that operates a continuously variable transmission for traveling, and a link that can be held in a state in which the shift pedal is depressed to a high speed side (Patent Document 1). 5) of FIG. 5 and a notch lever (21 of FIG. 5 of Patent Document 1) are provided, and when the driver depresses the right and left brake pedals, the notch lever is operated away from the link to change the speed. The holding of the pedal is released, and the shift pedal and the continuously variable transmission for traveling are operated to the neutral position (stop position) side by a neutral device (10 in FIG. 2 of Patent Document 1).

特開２００１−３２９２６号公報JP 2001-32926 A

特許文献１では、例えば旋回時に運転者が右又は左のブレーキペダルを踏み操作した場合、走行用の無段変速装置は停止位置側に操作されず、高速側に残された状態となり、制動が掛かっていない右又は左の後輪には、走行用の無段変速装置の動力がそのまま伝達される。旋回は停止ではなく走行なので、走行用の無段変速装置を不必要に中立位置（停止位置）に操作しないように構成しており、旋回時に機体が停止してしまわないように構成している。   In Patent Document 1, for example, when the driver depresses the right or left brake pedal during a turn, the continuously variable transmission for traveling is not operated to the stop position side but remains on the high speed side, and braking is performed. The power of the continuously variable transmission for driving is directly transmitted to the right or left rear wheel that is not applied. Since the turn is not a stop but a run, the continuously variable transmission for travel is configured not to be unnecessarily operated to the neutral position (stop position), so that the airframe does not stop during the turn. .

しかしながら、小回り旋回を行う場合、走行用の無段変速装置が高速側に残された状態であると（高速で小回り旋回する状態になると）、運転者の前輪の操向操作による機体の向きの修正が遅れてしまうことがあるので、運転者にとって高速での小回り旋回は操縦が難しいものになることがある。   However, when performing a small turn, if the continuously variable transmission for traveling is left on the high speed side (when it is in a state of making a small turn at a high speed), the direction of the body by the steering operation of the front wheel of the driver is changed. Since the correction may be delayed, a small turn at high speed may be difficult for the driver to maneuver.

本発明は、右及び左のブレーキペダル、右及び左のブレーキ、走行用の無段変速装置を備えた作業車において、直進時に右及び左のブレーキペダルが踏み操作されて、右及び左のブレーキが制動側に操作されると、走行用の無段変速装置が高速側から停止位置側に操作されるようにしながら、小回り旋回時の操縦性を向上させることを目的としている。   The present invention relates to a work vehicle equipped with right and left brake pedals, right and left brakes, and a continuously variable transmission for traveling, and the right and left brake pedals are stepped on when traveling straight, so that the right and left brakes are operated. When the vehicle is operated to the braking side, the traveling continuously variable transmission is operated from the high speed side to the stop position side, and the object is to improve the maneuverability during the small turn.

［Ｉ］
（構成）
本発明の第１特徴は、作業車において次のように構成することにある。
人為的に操作される右及び左のブレーキペダルと、右及び左の走行装置用の右及び左のブレーキとを備える。右のブレーキペダルが踏み操作されると連係機構を介して右のブレーキが制動側に操作されるように構成し、左のブレーキペダルが踏み操作されると連係機構を介して左のブレーキが制動側に操作されるように構成する。
停止位置から高速側に操作自在な走行用の無段変速装置と、右及び左のブレーキペダルの操作位置を検出する操作位置センサーとを備える。
右及び左のブレーキペダルの操作位置が同じ状態で右及び左のブレーキペダルが踏み操作されると、走行用の無段変速装置を停止位置側に操作する第１減速手段を備える。
右及び左のブレーキペダルの操作位置が異なる状態で右及び左のブレーキペダルが踏み操作されると、踏み操作解除位置に近い側の右又は左のブレーキペダルの操作位置に基づき、踏み操作解除位置に近い側の右又は左のブレーキペダルの操作位置が制動側限度位置に近づくほど、走行用の無段変速装置を停止位置側に操作する第２減速手段を備える。 [I]
(Constitution)
The first feature of the present invention is that the work vehicle is configured as follows.
Artificially operated right and left brake pedals, and right and left brakes for right and left travel devices. When the right brake pedal is depressed, the right brake is operated to the braking side via the linkage mechanism, and when the left brake pedal is depressed, the left brake is braked via the linkage mechanism. To be operated sideways.
A continuously variable transmission for travel that can be operated from the stop position to the high speed side, and an operation position sensor that detects the operation positions of the right and left brake pedals.
When the right and left brake pedals are stepped on when the operation positions of the right and left brake pedals are the same, the first reduction means for operating the continuously variable transmission for traveling to the stop position side is provided.
If the right and left brake pedals are operated with the right and left brake pedals in different positions, the stepping operation release position is based on the operation position of the right or left brake pedal closer to the stepping operation release position. The second reduction means for operating the continuously variable transmission for traveling to the stop position side as the operation position of the right or left brake pedal closer to the position approaches the braking side limit position.

（作用）
本発明の第１特徴によれば、運転者が右及び左のブレーキペダルを踏み操作した場合、右及び左のブレーキペダルの操作位置が同じ状態であると、右及び左のブレーキの制動力が同じ状態となるのであり、直進時であると判断されて、走行用の無段変速装置が高速側から停止位置側に操作される。これにより、走行用の無段変速装置が高速側に操作された状態で、右及び左のブレーキの制動力が発生する状態が防止されて、右及び左のブレーキへの負担が軽くなっている。 (Function)
According to the first feature of the present invention, when the driver depresses the right and left brake pedals, if the operating positions of the right and left brake pedals are the same, the braking force of the right and left brakes is Since this is the same state, it is determined that the vehicle is traveling straight, and the continuously variable transmission for traveling is operated from the high speed side to the stop position side. As a result, a state in which the braking force of the right and left brakes is generated in a state where the continuously variable transmission for traveling is operated on the high speed side is prevented, and the burden on the right and left brakes is reduced. .

本発明の第１特徴によれば運転者が右及び左のブレーキペダルを踏み操作した場合、例えば右のブレーキペダルが大きく踏み操作されながら（踏み操作解除位置から遠い側）、左のブレーキペダルが小さく踏み操作されたとする（踏み操作解除位置に近い側）。この状態において、右のブレーキペダルの操作位置により右のブレーキの制動力が大きなものになり、右への小回り旋回が行えるのであり、左のブレーキペダルの操作位置に基づき、走行用の無段変速装置が停止位置側に操作される。   According to the first feature of the present invention, when the driver depresses the right and left brake pedals, for example, while the right brake pedal is largely depressed (the far side from the depressing operation release position), the left brake pedal is Suppose that a small stepping operation is performed (side closer to the stepping operation release position). In this state, the braking force of the right brake is increased by the operating position of the right brake pedal, and a small turn to the right can be performed. Based on the operating position of the left brake pedal, the continuously variable transmission for driving The device is operated to the stop position side.

従って、右のブレーキペダルの操作位置により右のブレーキの制動力が大きなものになることにより、右への小回り旋回を行うことができるのであり、左のブレーキペダルの操作位置に基づき、走行用の無段変速装置が停止位置側に操作されることにより、機体の走行速度が低下するので、運転者の前輪の操向操作による機体の向きの修正が遅れてしまうことが少なくなり、運転者にとって右への小回り旋回時の操縦が楽になる。
この場合、左のブレーキペダルの操作位置が制動側限度位置に近づくほど、走行用の無段変速装置が停止位置側に操作されるので、左のブレーキペダルの操作位置を調節することにより、右への小回り旋回時の機体の走行速度を調節することができる。
以上の状態は、例えば左のブレーキペダルが大きく踏み操作されながら（踏み操作解除位置から遠い側）、右のブレーキペダルが小さく踏み操作された場合（踏み操作解除位置に近い側）においても、同様である。 Therefore, the braking force of the right brake is increased by the operation position of the right brake pedal, so that a small turn to the right can be performed. Based on the operation position of the left brake pedal, When the continuously variable transmission is operated to the stop position side, the traveling speed of the fuselage decreases, so that the correction of the orientation of the fuselage due to the steering operation of the driver's front wheels is less likely to be delayed. Maneuvering during a small turn to the right is easier.
In this case, as the operating position of the left brake pedal approaches the braking limit position, the continuously variable transmission for driving is operated to the stop position side. Therefore, by adjusting the operating position of the left brake pedal, It is possible to adjust the traveling speed of the aircraft during a small turn.
The above state is the same even when, for example, the left brake pedal is depressed greatly (the side far from the depression operation release position) and the right brake pedal is depressed a little (on the side closer to the depression operation release position) It is.

（発明の効果）
本発明の第１特徴によると、右及び左のブレーキペダル、右及び左のブレーキ、走行用の無段変速装置を備えた作業車において、小回り旋回時に踏み操作解除位置に近い側の右又は左のブレーキペダルの操作位置により、小回り旋回時の機体の走行速度を低下及び調節することができて、運転者の前輪の操向操作による機体の向きの修正が遅れてしまうことが少なくなり、小回り旋回時の操縦性を向上させることができた。
本発明の第１特徴によると、直進時に右及び左のブレーキペダルが踏み操作されて、右及び左のブレーキが制動側に操作されると、走行用の無段変速装置が高速側から停止位置側に操作されるように構成しており、右及び左のブレーキへの負担が軽くなっている。 (The invention's effect)
According to the first aspect of the present invention, in a work vehicle equipped with right and left brake pedals, right and left brakes, and a continuously variable transmission for traveling, the right or left on the side close to the stepping release position when turning slightly The operating position of the brake pedal can reduce and adjust the traveling speed of the aircraft when making a small turn, reducing the delay in correcting the orientation of the aircraft due to the steering operation of the driver's front wheels. The maneuverability during turning was improved.
According to the first feature of the present invention, when the right and left brake pedals are stepped on when traveling straight and the right and left brakes are operated to the braking side, the continuously variable transmission for traveling is stopped from the high speed side. The load to the right and left brakes is reduced.

［ＩＩ］
（構成）
本発明の第２特徴は、本発明の第１特徴の作業車において次のように構成することにある。
踏み操作解除位置と制動側限度位置との間の踏み操作範囲において、踏み操作解除位置と制動側限度位置との間に設定操作位置を設定し、右及び左のブレーキペダルの操作位置が踏み操作解除位置と設定操作位置との間であると、右及び左のブレーキが解除状態に操作され、右及び左のブレーキペダルの操作位置が設定操作位置から制動側限度位置に操作されるほど、右及び左のブレーキが解除状態から制動側に操作されるように構成する。
右及び左のブレーキペダルの操作位置が異なる状態で、右及び左のブレーキペダルが踏み操作されると、踏み操作解除位置に近い側の右又は左のブレーキペダルの操作位置に基づき、踏み操作解除位置と設定操作位置との間において、踏み操作解除位置に近い側の右又は左のブレーキペダルの操作位置が設定操作位置に近づくほど、走行用の無段変速装置を停止位置側に操作するように、第２減速手段を構成する。 [II]
(Constitution)
The second feature of the present invention is that the work vehicle of the first feature of the present invention is configured as follows.
In the step operation range between the step operation release position and the brake side limit position, a set operation position is set between the step operation release position and the brake side limit position, and the operation positions of the right and left brake pedals are the step operation. If it is between the release position and the set operation position, the right and left brakes are operated in the release state, and the right and left brake pedal operation positions are moved from the set operation position to the braking side limit position. The left brake is operated from the released state to the braking side.
When the right and left brake pedals are operated in different positions and the right and left brake pedals are operated, the stepping operation is released based on the operation position of the right or left brake pedal closer to the stepping operation release position. Between the position and the set operation position, the closer the operation position of the right or left brake pedal closer to the stepping operation release position approaches the set operation position, the more the continuously variable transmission for driving is operated to the stop position side. In addition, the second reduction means is configured.

（作用）
本発明の第２特徴によると、本発明の第１特徴と同様に前項［Ｉ］に記載の「作用」を備えており、これに加えて以下のような「作用」を備えている。
右（左）のブレーキペダル、右（左）のブレーキ、右（左）のブレーキペダルと右（右）のブレーキとを連係する連係機構を備えた場合、右（左）のブレーキペダルが踏み操作解除位置から踏み操作され始めると、直ぐに右（左）のブレーキの制動力が発生し始めるわけではなく、右（左）のブレーキペダルが踏み操作解除位置からある程度踏み操作されてから、右（左）のブレーキの制動力が発生し始めるように構成されることが多い（右（左）のブレーキペダル及び右（左）のブレーキの遊び）。 (Function)
According to the second feature of the present invention, the “action” described in the preceding item [I] is provided in the same manner as the first feature of the present invention, and in addition to this, the following “action” is provided.
If you have a linkage mechanism that links the right (left) brake pedal, right (left) brake, right (left) brake pedal, and right (right) brake, the right (left) brake pedal can be operated As soon as the stepping operation is started from the release position, the braking force of the right (left) brake does not start to be generated. Instead, the right (left) brake pedal is stepped from the stepping release position to the right (left). ) Is often configured to begin to generate braking force (right (left) brake pedal and right (left) brake play).

本発明の第２特徴によると、運転者が右及び左のブレーキペダルを踏み操作した場合、例えば右のブレーキペダルが大きく踏み操作され（踏み操作解除位置から遠い側）、左のブレーキペダルが小さく踏み操作されたとする（踏み操作解除位置に近い側）。この状態において、左のブレーキペダルの操作位置により走行用の無段変速装置が停止位置側に操作される場合、左のブレーキペダルの操作位置は踏み操作解除位置と設定操作位置との間に位置している状態が多く、左のブレーキは解除状態に操作されて制動力を発生していないことが多い。   According to the second feature of the present invention, when the driver depresses the right and left brake pedals, for example, the right brake pedal is largely depressed (on the side far from the depressing position), and the left brake pedal is small. Assume that a stepping operation has been performed (side closer to the stepping operation release position). In this state, when the continuously variable transmission for driving is operated to the stop position side by the operation position of the left brake pedal, the operation position of the left brake pedal is located between the stepping operation release position and the set operation position. In many cases, the left brake is operated in a released state and does not generate a braking force.

これにより、本発明の第２特徴によると、右のブレーキペダルの操作位置により右のブレーキの制動力が大きなものになって、右への小回り旋回が行われる際に、左のブレーキに制動力が発生して、右への小回り旋回に支障を来すと言うようなことがない。
以上の状態は、例えば左のブレーキペダルが大きく踏み操作され（踏み操作解除位置から遠い側）、右のブレーキペダルが小さく踏み操作された場合（踏み操作解除位置に近い側）においても、同様である。 Thus, according to the second feature of the present invention, the braking force of the right brake is increased by the operating position of the right brake pedal, and when the small turn to the right is performed, the braking force is applied to the left brake. Will not interfere with the small turn to the right.
The above state is the same even when, for example, the left brake pedal is depressed greatly (the side far from the stepping release position) and the right brake pedal is depressed small (the side near the stepping release position). is there.

（発明の効果）
本発明の第２特徴によると、本発明の第１特徴と同様に前項［Ｉ］に記載の「発明の効果」を備えており、これに加えて以下のような「発明の効果」を備えている。
本発明の第２特徴によると、右（左）のブレーキペダルの操作位置により右（左）のブレーキの制動力が大きなものになって、右（左）への小回り旋回が行われる際に、左（右）のブレーキに制動力が発生して、右（左）への小回り旋回に支障を来すと言うようなことが少なくなって、小回り旋回時の旋回性能を向上させることができた。 (The invention's effect)
According to the second feature of the present invention, the “effect of the invention” described in the preceding item [I] is provided in the same manner as the first feature of the present invention. In addition, the following “effect of the invention” is provided. ing.
According to the second feature of the present invention, when the braking force of the right (left) brake is increased by the operation position of the right (left) brake pedal, and the small turn to the right (left) is performed, The braking force was generated in the left (right) brake, and it was less likely to interfere with the small turn to the right (left), and the turning performance during the small turn could be improved. .

［１］
図１及び図２に示すように、右及び左の前輪１、右及び左の後輪２（右及び左の走行装置に相当）で支持された機体の中央部に運転部３が形成されて、作業車の一例である四輪駆動型の農用トラクタが構成されている。機体の前部に備えられたエンジン４の動力が、主クラッチ（図示せず）、静油圧式無段変速装置５（走行用の無段変速装置に相当）、ギヤ変速式の副変速装置（図示せず）、後輪デフ機構（図示せず）を介して右及び左の後輪２に伝達されており、後輪デフ機構の直前から分岐した動力が、前輪変速装置（図示せず）及び前輪デフ機構（図示せず）を介して、右及び左の前輪１に伝達されている。 [1]
As shown in FIGS. 1 and 2, a driving unit 3 is formed at the center of the airframe supported by the right and left front wheels 1 and the right and left rear wheels 2 (corresponding to right and left traveling devices). A four-wheel drive agricultural tractor, which is an example of a work vehicle, is configured. The power of the engine 4 provided in the front part of the machine body includes a main clutch (not shown), a hydrostatic continuously variable transmission 5 (corresponding to a continuously variable transmission for traveling), and a gear transmission type auxiliary transmission ( (Not shown), power transmitted to the right and left rear wheels 2 via a rear wheel differential mechanism (not shown), and the power branched immediately before the rear wheel differential mechanism is a front wheel transmission (not shown). And, it is transmitted to the right and left front wheels 1 via a front wheel differential mechanism (not shown).

図３に示すように、静油圧式無段変速装置５は、中立位置Ｎ（停止位置に相当）、中立位置Ｎから前進Ｆの高速側及び後進Ｒの高速側に無段階に操作自在に構成されている。静油圧式無段変速装置５のトラニオン軸５ａを操作する電動シリンダ６が備えられて、制御装置８により電動シリンダ６が操作されるように構成されており、静油圧式無段変速装置５のトラニオン軸５ａの位置を検出するポテンショメータ７が備えられ、ポテンショメータ７の検出値が制御装置８に入力されている。   As shown in FIG. 3, the hydrostatic continuously variable transmission 5 is configured to be steplessly operable from a neutral position N (corresponding to a stop position) from the neutral position N to the high speed side of forward F and the high speed side of reverse R. Has been. An electric cylinder 6 for operating the trunnion shaft 5 a of the hydrostatic continuously variable transmission 5 is provided, and the electric cylinder 6 is operated by the control device 8. A potentiometer 7 for detecting the position of the trunnion shaft 5 a is provided, and a detection value of the potentiometer 7 is input to the control device 8.

前輪変速装置は、右及び左の前輪１、右及び左の後輪２が略同じ速度で駆動される標準状態、右及び左の前輪１が右及び左の後輪２よりも高速で駆動される増速状態に、操作自在に構成されている。右及び左の前輪１が直進位置から右及び左の設定角度の範囲に操向操作されると、前輪変速装置が標準状態に操作され、右及び左の前輪１が右及び左の設定角度を越えて右及び左に操向操作されると、前輪変速装置が増速状態に操作される。   In the front wheel transmission, the right and left front wheels 1, the right and left rear wheels 2 are driven at substantially the same speed, and the right and left front wheels 1 are driven at a higher speed than the right and left rear wheels 2. It is configured so that it can be operated in a speed increasing state. When the right and left front wheels 1 are steered from the straight travel position to the right and left set angle ranges, the front wheel transmission is operated to the standard state, and the right and left front wheels 1 are set to the right and left set angles. When the steering operation is performed to the right and to the left, the front wheel transmission is operated to the speed increasing state.

［２］
次に、変速レバー１０及び変速ペダル１２について説明する。
図１，２，３に示すように、運転部３において運転座席９の右横側に、変速レバー１０が備えられており、変速レバー１０の操作位置を検出するポテンショメータ１１が備えられて、ポテンショメータ１１の検出値が制御装置８に入力されている。変速レバー１０は中立位置Ｎと前進Ｆの最高速位置ＦＭとの間で操作自在であり、ある操作位置に操作してから手を離しても、その操作位置に保持されるように構成されている。これにより、変速レバー１０の操作位置に基づいて、制御装置８及び電動シリンダ６により、静油圧式無段変速装置５のトラニオン軸５ａが以下のように操作される。 [2]
Next, the transmission lever 10 and the transmission pedal 12 will be described.
As shown in FIGS. 1, 2, and 3, in the driving unit 3, a speed change lever 10 is provided on the right side of the driver seat 9, and a potentiometer 11 that detects an operation position of the speed change lever 10 is provided. 11 detection values are input to the control device 8. The speed change lever 10 can be operated between the neutral position N and the highest speed position FM of the forward movement F, and is configured to be held at the operation position even if the hand is released after being operated to a certain operation position. Yes. Accordingly, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated as follows by the control device 8 and the electric cylinder 6 based on the operation position of the transmission lever 10.

図３に示すように、変速レバー１０が中立位置Ｎに操作されると、静油圧式無段変速装置５のトラニオン軸５ａが中立位置Ｎに操作され、変速レバー１０が前進Ｆの最高速位置ＦＭに操作されると、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの最高速位置ＦＭに操作される。変速レバー１０が中立位置Ｎと前進Ｆの最高速位置ＦＭとの間に操作されると、静油圧式無段変速装置５のトラニオン軸５ａが変速レバー１０の操作位置に対応する位置に操作される。このように、変速レバー１０を操作することにより、静油圧式無段変速装置５のトラニオン軸５ａを中立位置Ｎと前進Ｆの最高速位置ＦＭとの間に操作及び保持して、一定速度での前進の走行が行える。   As shown in FIG. 3, when the speed change lever 10 is operated to the neutral position N, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated to the neutral position N, and the speed change lever 10 is at the highest speed position of forward F. When operated to FM, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated to the highest speed position FM of forward movement F. When the transmission lever 10 is operated between the neutral position N and the highest speed position FM of the forward movement F, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated to a position corresponding to the operation position of the transmission lever 10. The In this way, by operating the speed change lever 10, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated and held between the neutral position N and the highest speed position FM of the forward movement F at a constant speed. You can move forward.

図１，２，３に示すように、運転部３において右下部に変速ペダル１２が備えられており、変速パダル１２の操作位置を検出するポテンショメータ１３が備えられて、ポテンショメータ１３の検出値が制御装置８に入力されている。変速ペダル１２は中立位置Ｎ、中立位置Ｎから前進Ｆの高速側及び後進Ｒの高速側に操作自在に構成されており、中立位置Ｎに付勢されている。これにより、変速ペダル１２の操作位置に基づいて、制御装置８及び電動シリンダ６により、静油圧式無段変速装置５のトラニオン軸５ａが以下のように操作される。   As shown in FIGS. 1, 2, and 3, the operating unit 3 is provided with a speed change pedal 12 at a lower right portion, a potentiometer 13 that detects an operation position of the speed change padal 12, and a detection value of the potentiometer 13 is controlled. Input to the device 8. The shift pedal 12 is configured to be operable from the neutral position N and the neutral position N to the high speed side of forward F and the high speed side of reverse R, and is biased to the neutral position N. Thereby, based on the operation position of the speed change pedal 12, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated by the control device 8 and the electric cylinder 6 as follows.

図３に示すように、変速レバー１０が中立位置Ｎに操作されている状態において、変速ペダル１２を中立位置Ｎから前進Ｆの高速側（前進Ｆの最高速位置ＦＭ）、及び後進Ｒの高速側（後進Ｒの最高速位置ＲＭ）に操作すると、静油圧式無段変速装置５のトラニオン軸５ａが変速ペダル１２の操作位置に対応する位置に操作される。
変速レバー１０が中立位置Ｎから前進Ｆの高速側に操作されている状態（静油圧式無段変速装置５のトラニオン軸５ａが変速レバー１０の操作位置に対応する位置に操作されている状態）において、変速ペダル１２を後進Ｒの高速側に操作しても、変速ペダル１２の操作が無視される。 As shown in FIG. 3, in a state where the shift lever 10 is operated to the neutral position N, the shift pedal 12 is moved from the neutral position N to the high speed side of the forward F (the highest speed position FM of the forward F) and the high speed of the reverse R. When operated to the side (the highest speed position RM for reverse R), the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated to a position corresponding to the operation position of the shift pedal 12.
The state where the shift lever 10 is operated from the neutral position N to the high speed side of the forward movement F (the state where the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated to a position corresponding to the operation position of the shift lever 10) In this case, even if the shift pedal 12 is operated to the high speed side of the reverse R, the operation of the shift pedal 12 is ignored.

図３に示すように、変速レバー１０が中立位置Ｎから前進Ｆの高速側に操作されている状態（静油圧式無段変速装置５のトラニオン軸５ａが変速レバー１０の操作位置に対応する位置に操作されている状態）において、変速ペダル１２を前進Ｆの高速側に操作する場合、変速ペダル１２が変速レバー１０の操作位置に対応する位置よりも前進Ｆの高速側に操作されると、静油圧式無段変速装置５のトラニオン軸５ａが変速ペダル１２の操作位置に対応する位置に操作される。次に変速ペダル１２が変速レバー１０の操作位置に対応する位置よりも中立位置Ｎ側に操作されると、静油圧式無段変速装置５のトラニオン軸５ａが変速レバー１０の操作位置に対応する位置に操作される。   As shown in FIG. 3, the speed change lever 10 is operated from the neutral position N to the high speed side of the forward movement F (the position where the trunnion shaft 5 a of the hydrostatic continuously variable transmission 5 corresponds to the operation position of the speed change lever 10. In the state where the shift pedal 12 is operated to the high speed side of the forward movement F, when the shift pedal 12 is operated to the high speed side of the forward movement F from the position corresponding to the operation position of the transmission lever 10, The trunnion shaft 5 a of the hydrostatic continuously variable transmission 5 is operated to a position corresponding to the operation position of the shift pedal 12. Next, when the speed change pedal 12 is operated to the neutral position N side from the position corresponding to the operation position of the speed change lever 10, the trunnion shaft 5 a of the hydrostatic continuously variable transmission 5 corresponds to the operation position of the speed change lever 10. Manipulated into position.

［３］
次に、右及び左のブレーキペダル１５，１６について説明する。
図１，２，３に示すように、運転部３において左下部に、主クラッチを伝動及び遮断状態に操作するクラッチペダル１４が備えられており、運転部３において右下部の変速ペダル１２の前方に、右及び左のブレーキペダル１５，１６が左右方向に並べて備えられている。右の後輪２を制動可能な右のブレーキ１７、及び左の後輪２を制動可能な左のブレーキ１８が備えられており、右のブレーキペダル１５と右のブレーキ１７とが連係ロッド１９（連係機構に相当）を介して接続され、左のブレーキペダル１６と左のブレーキ１８とが連係ロッド１９（連係機構に相当）を介して接続されている。 [3]
Next, the right and left brake pedals 15 and 16 will be described.
As shown in FIGS. 1, 2, and 3, a clutch pedal 14 for operating the main clutch to transmit and disengage is provided in the lower left part of the driving unit 3. In addition, right and left brake pedals 15 and 16 are provided side by side in the left-right direction. A right brake 17 capable of braking the right rear wheel 2 and a left brake 18 capable of braking the left rear wheel 2 are provided, and the right brake pedal 15 and the right brake 17 are connected to the linkage rod 19 ( The left brake pedal 16 and the left brake 18 are connected via a linkage rod 19 (corresponding to a linkage mechanism).

図３及び図４の一点鎖線Ｃ１に示すように、右及び左のブレーキペダル１５，１６は、踏み操作解除位置Ａ１及び制動側限度位置Ａ２に亘って踏み操作自在であり、踏み操作解除位置Ａ１に付勢されている。踏み操作解除位置Ａ１と制動側限度位置Ａ２との間に第１設定操作位置Ａ３（設定操作位置に相当）が設定されており、右及び左のブレーキペダル１５，１６を踏み操作した場合、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが踏み操作解除位置Ａ１と第１設定操作位置Ａ３との間であると、右及び左のブレーキ１７，１８が解除状態に操作されている（右及び左のブレーキペダル１５，１６、連係ロッド１９、右及び左のブレーキ１７，１８の遊び）。   As shown by the one-dot chain line C1 in FIGS. 3 and 4, the right and left brake pedals 15 and 16 can be stepped over the stepping operation release position A1 and the braking side limit position A2, and the stepping operation release position A1. Is being energized. The first setting operation position A3 (corresponding to the setting operation position) is set between the stepping operation release position A1 and the braking side limit position A2, and when the right and left brake pedals 15 and 16 are stepped on, When the operation positions AR and AL of the left brake pedals 15 and 16 are between the stepping operation release position A1 and the first setting operation position A3, the right and left brakes 17 and 18 are operated in the release state. (Play of right and left brake pedals 15, 16, linkage rod 19, right and left brakes 17, 18).

図３及び図４の一点鎖線Ｃ１に示すように、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが第１設定操作位置Ａ３になると、右及び左のブレーキ１７，１８の制動力が発生し始め、右及び左のブレーキペダル１５，１６を第１設定操作位置Ａ３から制動側限度位置Ａ２に踏み操作するほど、右及び左のブレーキ１７，１８の制動力が大きくなっていき、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが制動側限度位置Ａ２になると、右及び左のブレーキ１７，１８の制動力が最大となる。   3 and 4, when the operation positions AR and AL of the right and left brake pedals 15 and 16 become the first setting operation position A3, the braking force of the right and left brakes 17 and 18 is indicated. When the right and left brake pedals 15 and 16 are stepped on from the first setting operation position A3 to the braking side limit position A2, the braking force of the right and left brakes 17 and 18 increases. When the operation positions AR, AL of the right and left brake pedals 15, 16 reach the braking side limit position A2, the braking forces of the right and left brakes 17, 18 are maximized.

図３に示すように、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬを検出するポテンショメータ２０（操作位置センサーに相当）が備えられており、ポテンショメータ２０の検出値が制御装置８に入力されている。この場合、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが踏み操作解除位置Ａ１であると、ポテンショメータ２０の検出値は最小値となり、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが制動側限度位置Ａ２であると、ポテンショメータ２０の検出値は最大値となる。   As shown in FIG. 3, a potentiometer 20 (corresponding to an operation position sensor) for detecting the operation positions AR and AL of the right and left brake pedals 15 and 16 is provided, and the detected value of the potentiometer 20 is transmitted to the control device 8. Have been entered. In this case, when the operation positions AR and AL of the right and left brake pedals 15 and 16 are the stepping operation release position A1, the detected value of the potentiometer 20 becomes the minimum value, and the operation positions of the right and left brake pedals 15 and 16 When AR and AL are the braking side limit position A2, the detection value of the potentiometer 20 is the maximum value.

右及び左のブレーキペダル１５，１６が踏み操作解除位置Ａ１から制動側限度位置Ａ２に踏み操作される場合、直進時の停止時には、右及び左のブレーキペダル１５，１６が同じ操作位置ＡＲ，ＡＬに踏み操作される。
右への小回り旋回時、右及び左の前輪１が右の設定角度を越えて右に操向操作され、前輪変速装置が増速状態に操作された状態で、右のブレーキペダル１５だけが踏み操作されることがある。この場合、右のブレーキペダル１５が大きく踏み操作されながら（踏み操作解除位置Ａ１から遠い側）、左のブレーキペダル１６が小さく踏み操作されることがある（踏み操作解除位置Ａ１に近い側）。
左への小回り旋回時、右及び左の前輪１が左の設定角度を越えて左に操向操作され、前輪変速装置が増速状態に操作された状態で、左のブレーキペダル１６だけが踏み操作されることがある。この場合、左のブレーキペダル１６が大きく踏み操作されながら（踏み操作解除位置Ａ１から遠い側）、右のブレーキペダル１５が小さく踏み操作されることがある（踏み操作解除位置Ａ１に近い側）。 When the right and left brake pedals 15 and 16 are stepped from the stepping operation release position A1 to the braking side limit position A2, the right and left brake pedals 15 and 16 are at the same operation positions AR and AL when stopped straight. Is stepped on.
During a small turn to the right, the right and left front wheels 1 are steered to the right beyond the right set angle, and only the right brake pedal 15 is depressed while the front wheel transmission is operated in the accelerated state. May be manipulated. In this case, while the right brake pedal 15 is greatly depressed (on the side far from the depression operation release position A1), the left brake pedal 16 may be depressed a little (on the side closer to the depression operation release position A1).
During a small turn to the left, the right and left front wheels 1 are steered to the left beyond the left set angle, and only the left brake pedal 16 is depressed while the front wheel transmission is operated in the accelerated state. May be manipulated. In this case, while the left brake pedal 16 is largely depressed (on the side far from the depression operation release position A1), the right brake pedal 15 may be depressed a little (on the side closer to the depression operation release position A1).

［４］
次に、右及び左のブレーキペダル１５，１６が踏み操作解除位置Ａ１から制動側限度位置Ａ２に踏み操作される場合（右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが同じ状態）において、静油圧式無段変速装置５と右及び左のブレーキペダル１５，１６との関係の前半について、図５に基づいて説明する。
右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが検出されており（ステップＳ１）、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが比較されている（ステップＳ２）。右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが同じ状態であると、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが操作値ＡＡとして設定される（ステップＳ３）。 [4]
Next, when the right and left brake pedals 15 and 16 are stepped from the stepping operation release position A1 to the braking side limit position A2 (the operation positions AR and AL of the right and left brake pedals 15 and 16 are the same). The first half of the relationship between the hydrostatic continuously variable transmission 5 and the right and left brake pedals 15 and 16 will be described with reference to FIG.
The operation positions AR and AL of the right and left brake pedals 15 and 16 are detected (step S1), and the operation positions AR and AL of the right and left brake pedals 15 and 16 are compared (step S2). If the operation positions AR, AL of the right and left brake pedals 15, 16 are in the same state, the operation positions AR, AL of the right and left brake pedals 15, 16 are set as the operation value AA (step S3).

図４の実線Ｃ２に示すように、踏み操作解除位置Ａ１と第１設定操作位置Ａ３との間で踏み操作解除位置Ａ１に近い位置に、第２設定操作位置Ａ４が設定されている。これにより、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが同じ状態において、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が、踏み操作解除位置Ａ１と第２設定操作位置Ａ４との間であると（ステップＳ６）、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）に関係なく、変速レバー１０及び変速ペダル１２の操作位置に基づいて、静油圧式無段変速装置５のトラニオン軸５ａが操作されている（前項［２］参照）。この間、右及び左のブレーキ１７，１８が解除状態に操作されている。   As shown by a solid line C2 in FIG. 4, the second setting operation position A4 is set at a position close to the stepping operation release position A1 between the stepping operation release position A1 and the first setting operation position A3. As a result, when the operation positions AR and AL of the right and left brake pedals 15 and 16 are the same, the operation positions AR and AL (operation values AA) of the right and left brake pedals 15 and 16 become the stepping operation release position A1. And the second setting operation position A4 (step S6), regardless of the operation positions AR and AL (operation values AA) of the right and left brake pedals 15 and 16, the shift lever 10 and the shift pedal 12 are Based on the operation position, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated (see the previous item [2]). During this time, the right and left brakes 17 and 18 are operated in the released state.

図３及び図４に示すように、静油圧式無段変速装置５において、中立位置Ｎの近傍に前進Ｆの設定低速位置Ｆ１、及び後進Ｒの設定低速位置Ｒ１が設定されている。静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆ及び後進Ｒの設定低速位置Ｆ１，Ｒ１に操作されると、機体が低速で前進又は後進する状態となる（クリープ状態）。   As shown in FIGS. 3 and 4, in the hydrostatic continuously variable transmission 5, a set low speed position F1 for forward F and a set low speed position R1 for reverse R are set near the neutral position N. When the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated to the set low speed positions F1 and R1 for forward F and reverse R, the airframe moves forward or reverse at a low speed (creep state).

図４の実線Ｃ２に示すように、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが同じ状態（操作値ＡＡ＝ＡＲ（ＡＬ））において、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が、第２設定操作位置Ａ４と第１設定操作位置Ａ３との間であったとする（ステップＳ６）。
変速レバー１０が前進Ｆに操作されている状態では（ステップＳ７）、静油圧式無段変速装置５のトラニオン軸５ａが、変速レバー１０の操作位置に対応する位置と前進Ｆの設定低速位置Ｆ１との間において操作されるのであり、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が第１設定操作位置Ａ３に近づくほど、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの設定低速位置Ｆ１側に操作される。右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が第１設定操作位置Ａ３になると、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの設定低速位置Ｆ１に到達する（ステップＳ９）（第１減速手段に相当）。この間、右及び左のブレーキ１７，１８が解除状態に操作されている。 As shown by the solid line C2 in FIG. 4, when the operation positions AR and AL of the right and left brake pedals 15 and 16 are the same (operation value AA = AR (AL)), the right and left brake pedals 15 and 16 It is assumed that the operation positions AR and AL (operation value AA) are between the second setting operation position A4 and the first setting operation position A3 (step S6).
In a state in which the speed change lever 10 is operated in the forward direction F (step S7), the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is positioned at the position corresponding to the operation position of the speed change lever 10 and the set low speed position F1 of the forward speed F. The operation positions AR and AL (operation values AA) of the right and left brake pedals 15 and 16 are closer to the first setting operation position A3, so that the hydrostatic continuously variable transmission 5 The trunnion shaft 5a is operated to the set low speed position F1 side of the forward movement F. When the operation positions AR and AL (operation values AA) of the right and left brake pedals 15 and 16 reach the first setting operation position A3, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is set to the forward low speed setting F1. (Step S9) (corresponding to the first deceleration means). During this time, the right and left brakes 17 and 18 are operated in the released state.

図４の実線Ｃ２に示すように、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが同じ状態（操作値ＡＡ＝ＡＲ（ＡＬ））において、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が、第２設定操作位置Ａ４と第１設定操作位置Ａ３との間であったとする（ステップＳ６）。
変速ペダル１２が前進Ｆ（後進Ｒ）に操作されている状態では（ステップＳ８）、変速ペダル１２から足が離されてから右及び左のブレーキペダル１５，１６が踏み操作される状態となるので、変速ペダル１２が前進Ｆ（後進Ｒ）から中立位置Ｎに戻りながら、右及び左のブレーキペダル１５，１６が踏み操作される状態となる。 As shown by the solid line C2 in FIG. 4, when the operation positions AR and AL of the right and left brake pedals 15 and 16 are the same (operation value AA = AR (AL)), the right and left brake pedals 15 and 16 It is assumed that the operation positions AR and AL (operation value AA) are between the second setting operation position A4 and the first setting operation position A3 (step S6).
When the shift pedal 12 is operated forward F (reverse R) (step S8), the right and left brake pedals 15 and 16 are stepped on after the shift pedal 12 is released. The right and left brake pedals 15 and 16 are stepped on while the shift pedal 12 returns from the forward F (reverse R) to the neutral position N.

この場合、図４の実線Ｃ２に示すように、ステップＳ９と同様に、静油圧式無段変速装置５のトラニオン軸５ａが、変速ペダル１２の操作位置に対応する位置と前進Ｆの設定低速位置Ｆ１（後進Ｒの設定低速位置Ｒ１）との間において操作されるのであり、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が第１設定操作位置Ａ３に近づくほど、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの設定低速位置Ｆ１（後進Ｒの設定低速位置Ｒ１）側に操作される。右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が第１設定操作位置Ａ３になると、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの設定低速位置Ｆ１（後進Ｒの設定低速位置Ｒ１）に到達する（第１減速手段に相当）（ステップＳ１０，Ｓ１１）。この間、右及び左のブレーキ１７，１８が解除状態に操作されている。   In this case, as indicated by the solid line C2 in FIG. 4, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is located at the position corresponding to the operating position of the shift pedal 12 and the set low speed position of the forward F, as in step S9. F1 (reverse R set low speed position R1) is operated, and the operation positions AR and AL (operation values AA) of the right and left brake pedals 15 and 16 become closer to the first set operation position A3. The trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated to the set low speed position F1 for forward F (set low speed position R1 for reverse R). When the operation positions AR and AL (operation values AA) of the right and left brake pedals 15 and 16 reach the first setting operation position A3, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is set to the forward low speed setting F1. It reaches (set low speed position R1 for reverse R) (corresponding to first deceleration means) (steps S10, S11). During this time, the right and left brakes 17 and 18 are operated in the released state.

ステップＳ１０，Ｓ１１において、変速ペダル１２から足が離されて、変速ペダル１２が前進Ｆ（後進Ｒ）から中立位置Ｎに戻る際、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬに基づく静油圧式無段変速装置５のトラニオン軸５ａの位置に対し、変速ペダル１２の操作位置に対応する位置が中立位置Ｎ側になると（早く中立位置Ｎ側になると）、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が無視され、変速ペダル１２の操作位置に基づいて、静油圧式無段変速装置５のトラニオン軸５ａが操作される（早く前進Ｆの設定低速位置Ｆ１（後進Ｒの設定低速位置Ｒ１）に操作される）。   In steps S10 and S11, when the foot is released from the speed change pedal 12 and the speed change pedal 12 returns from the forward F (reverse R) to the neutral position N, the operation positions AR and AL of the right and left brake pedals 15 and 16 are set. When the position corresponding to the operation position of the speed change pedal 12 becomes the neutral position N side (early the neutral position N side) with respect to the position of the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 based, the right and left brakes The operation positions AR and AL (operation values AA) of the pedals 15 and 16 are ignored, and the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated based on the operation position of the shift pedal 12 (fast forward F Set low-speed position F1 (operated to reverse low-speed R set low-speed position R1)).

［５］
次に、右及び左のブレーキペダル１５，１６が踏み操作解除位置Ａ１から制動側限度位置Ａ２に踏み操作される場合（右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが同じ状態）において、静油圧式無段変速装置５と右及び左のブレーキペダル１５，１６との関係の後半について、図５に基づいて説明する。 [5]
Next, when the right and left brake pedals 15 and 16 are stepped from the stepping operation release position A1 to the braking side limit position A2 (the operation positions AR and AL of the right and left brake pedals 15 and 16 are the same). The second half of the relationship between the hydrostatic continuously variable transmission 5 and the right and left brake pedals 15 and 16 will be described with reference to FIG.

図４の実線Ｃ２に示すように、第１設定操作位置Ａ３と制動側限度位置Ａ２との間で制動側限度位置Ａ２に近い位置に、第３設定操作位置Ａ５が設定されている。
図４の実線Ｃ２に示すように、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが同じ状態において、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が、第１設定操作位置Ａ３と第３設定操作位置Ａ５との間であったとする（ステップＳ６）。 As shown by the solid line C2 in FIG. 4, the third setting operation position A5 is set at a position close to the braking side limit position A2 between the first setting operation position A3 and the braking side limit position A2.
As shown by the solid line C2 in FIG. 4, when the operation positions AR and AL of the right and left brake pedals 15 and 16 are the same, the operation positions AR and AL (operation values AA) of the right and left brake pedals 15 and 16 are the same. Is between the first setting operation position A3 and the third setting operation position A5 (step S6).

図４の実線Ｃ２に示すように、変速レバー１０が前進Ｆに操作されている状態（ステップＡ１２）及び変速ペダル１２が前進Ｆに操作されている状態（ステップＳ１３）では、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの設定低速位置Ｆ１に保持される（ステップＳ１４）。変速ペダル１２が後進Ｒに操作されている状態では（ステップＳ１３）、静油圧式無段変速装置５のトラニオン軸５ａが後進Ｒの設定低速位置Ｒ１に保持される（ステップＳ１５）。   As shown by the solid line C2 in FIG. 4, in the state where the shift lever 10 is operated in the forward direction F (step A12) and the state where the shift pedal 12 is operated in the forward direction F (step S13), the hydrostatic stepless The trunnion shaft 5a of the transmission 5 is held at the set low speed position F1 of the forward movement F (step S14). In a state where the shift pedal 12 is operated to reverse R (step S13), the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is held at the set low speed position R1 for reverse R (step S15).

図４の実線Ｃ２に示すように、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが同じ状態において、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が、第３設定操作位置Ａ５と制動側限度位置Ａ２との間であったとする（ステップＳ６）。この状態では、変速レバー１０及び変速ペダル１２に関係なく、静油圧式無段変速装置５のトラニオン軸５ａが中立位置Ｎに保持される（ステップＳ１６）。   As shown by the solid line C2 in FIG. 4, when the operation positions AR and AL of the right and left brake pedals 15 and 16 are the same, the operation positions AR and AL (operation values AA) of the right and left brake pedals 15 and 16 are the same. Is between the third setting operation position A5 and the braking side limit position A2 (step S6). In this state, regardless of the speed change lever 10 and the speed change pedal 12, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is held at the neutral position N (step S16).

この場合、図４の一点鎖線Ｃ１に示すように、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）において、第１設定操作位置Ａ３から右及び左のブレーキ１６，１７の制動力が発生し始めるのであり、右及び左のブレーキペダル１５，１６を第１設定操作位置Ａ３から制動側限度位置Ａ２に踏み操作するほど、右及び左のブレーキ１７，１８の制動力が大きくなっていき、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが制動側限度位置Ａ２になると、右及び左のブレーキ１７，１８の制動力が最大となる。   In this case, as shown by the one-dot chain line C1 in FIG. 4, the right and left brakes 16, 16 from the first set operation position A3 at the operation positions AR, AL (operation value AA) of the right and left brake pedals 15, 16 are shown. Thus, the braking force of the right and left brakes 17 and 18 is increased as the right and left brake pedals 15 and 16 are stepped from the first setting operation position A3 to the braking side limit position A2. When the operating positions AR and AL of the right and left brake pedals 15 and 16 reach the braking side limit position A2, the braking force of the right and left brakes 17 and 18 becomes maximum.

［６］
次に、右及び左のブレーキペダル１５，１６が踏み操作解除位置Ａ１から制動側限度位置Ａ２に踏み操作される場合（右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが異なる状態）において、静油圧式無段変速装置５と右及び左のブレーキペダル１５，１６との関係の前半について、図５に基づいて説明する。
右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが検出されており（ステップＳ１）、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが比較されている（ステップＳ２）。右のブレーキペダル１５の操作位置ＡＲが左のブレーキペダル１６の操作位置ＡＬよりも踏み操作解除位置Ａ１に近い状態であると、右のブレーキペダル１５の操作位置ＡＲが操作値ＡＡとして設定される（ステップＳ４）。左のブレーキペダル１６の操作位置ＡＬが右のブレーキペダル１５の操作位置ＡＲよりも踏み操作解除位置Ａ１に近い状態であると、左のブレーキペダル１６の操作位置ＡＬが操作値ＡＡとして設定される（ステップＳ５）。 [6]
Next, when the right and left brake pedals 15 and 16 are stepped from the stepping operation release position A1 to the braking side limit position A2 (the operation positions AR and AL of the right and left brake pedals 15 and 16 are different). The first half of the relationship between the hydrostatic continuously variable transmission 5 and the right and left brake pedals 15 and 16 will be described with reference to FIG.
The operation positions AR and AL of the right and left brake pedals 15 and 16 are detected (step S1), and the operation positions AR and AL of the right and left brake pedals 15 and 16 are compared (step S2). If the operation position AR of the right brake pedal 15 is closer to the stepping operation release position A1 than the operation position AL of the left brake pedal 16, the operation position AR of the right brake pedal 15 is set as the operation value AA. (Step S4). When the operation position AL of the left brake pedal 16 is closer to the stepping release position A1 than the operation position AR of the right brake pedal 15, the operation position AL of the left brake pedal 16 is set as the operation value AA. (Step S5).

右のブレーキペダル１５だけが踏み操作され、左のブレーキペダル１６が踏み操作されない状態、左のブレーキペダル１６だけが踏み操作され、右のブレーキペダル１５が踏み操作されない状態では、踏み操作されない右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬは、踏み操作解除位置Ａ１のままであるので（ステップＳ６）、踏み操作された右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬに関係なく、変速レバー１０及び変速ペダル１２の操作位置に基づいて、静油圧式無段変速装置５のトラニオン軸５ａが操作されている（前項［２］参照）。この間、踏み操作された右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬに基づいて、右又は左のブレーキ１７，１８が制動力を発生し、踏み操作されない右又は左のブレーキペダル１５，１６の右又は左のブレーキ１７，１８が解除状態に操作されている。   In a state where only the right brake pedal 15 is depressed and the left brake pedal 16 is not depressed, or only the left brake pedal 16 is depressed and the right brake pedal 15 is not depressed, Since the operation positions AR and AL of the left brake pedals 15 and 16 remain at the stepping operation release position A1 (step S6), the operation positions AR and AL of the right or left brake pedals 15 and 16 that have been stepped on are set. Regardless, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated based on the operation positions of the transmission lever 10 and the transmission pedal 12 (see [2] in the previous section). During this time, the right or left brakes 17 and 18 generate a braking force based on the operation positions AR and AL of the right or left brake pedals 15 and 16 that are stepped on, and the right or left brake pedal 15 that is not stepped on. , 16 right or left brakes 17 and 18 are operated in a released state.

右のブレーキペダル１５が大きく踏み操作されながら（踏み操作解除位置Ａ１から遠い側）、左のブレーキペダル１６が小さく踏み操作される（踏み操作解除位置Ａ１に近い側）状態、及び、左のブレーキペダル１６が大きく踏み操作されながら（踏み操作解除位置Ａ１から遠い側）、右のブレーキペダル１５が小さく踏み操作される（踏み操作解除位置Ａ１に近い側）状態において、踏み操作解除位置Ａ１に近い側の右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が、踏み操作解除位置Ａ１と第２設定操作位置Ａ４との間であると（ステップＳ６）、踏み操作解除位置Ａ１に近い側の右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）に関係なく、変速レバー１０及び変速ペダル１２の操作位置に基づいて、静油圧式無段変速装置５のトラニオン軸５ａが操作されている（前項［２］参照）。   A state in which the left brake pedal 16 is operated to be depressed a little (on the side closer to the depression operation release position A1) while the right brake pedal 15 is largely depressed (a side far from the depression operation release position A1), and the left brake Close to the stepping operation canceling position A1 when the right brake pedal 15 is operated to a small stepping (side closer to the stepping operation canceling position A1) while the pedal 16 is largely operated (a side far from the stepping operation canceling position A1). When the operation positions AR, AL (operation values AA) of the right or left brake pedals 15 and 16 are between the step operation release position A1 and the second set operation position A4 (step S6), the step operation is released. Regardless of the operation position AR, AL (operation value AA) of the right or left brake pedal 15, 16 on the side close to the position A1, the shift lever 10 and the shift pedal 12 are Based on the work position, trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated (refer to item [2]).

図４の実線Ｃ２に示すように、踏み操作解除位置Ａ１に近い側の右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が、第２設定操作位置Ａ４と第１設定操作位置Ａ３との間であったとする（ステップＳ６）。
前項［４］と同様に、変速レバー１０が前進Ｆに操作されている状態では（ステップＳ７）、静油圧式無段変速装置５のトラニオン軸５ａが、変速レバー１０の操作位置に対応する位置と前進Ｆの設定低速位置Ｆ１との間において操作されるのであり、踏み操作解除位置Ａ１に近い側の右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が第１設定操作位置Ａ３に近づくほど、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの設定低速位置Ｆ１側に操作される。踏み操作解除位置Ａ１に近い側の右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が第１設定操作位置Ａ３になると、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの設定低速位置Ｆ１に到達する（ステップＳ９）（第２減速手段に相当）。 As shown by the solid line C2 in FIG. 4, the operation positions AR, AL (operation values AA) of the right or left brake pedals 15, 16 on the side close to the stepping operation release position A1 are the second set operation position A4 and the first operation position A4. It is assumed that it is between the set operation position A3 (step S6).
As in the previous item [4], when the speed change lever 10 is operated to the forward F (step S7), the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is a position corresponding to the operation position of the speed change lever 10. And the set low speed position F1 of the forward F, the operation positions AR and AL (operation values AA) of the right or left brake pedals 15 and 16 on the side close to the stepping operation release position A1 are the first. The closer to the set operation position A3, the more the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated to the set low speed position F1 side of the forward F. When the operation positions AR and AL (operation values AA) of the right or left brake pedals 15 and 16 on the side close to the stepping operation release position A1 become the first set operation position A3, the trunnion shaft of the hydrostatic continuously variable transmission 5 is obtained. 5a reaches the set low speed position F1 for forward F (step S9) (corresponding to the second deceleration means).

図４の実線Ｃ２に示すように、踏み操作解除位置Ａ１に近い側の右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が、第２設定操作位置Ａ４と第１設定操作位置Ａ３との間であったとする（ステップＳ６）。
前項［４］と同様に、変速ペダル１２が前進Ｆ（後進Ｒ）に操作されている状態では（ステップＳ８）、変速ペダル１２から足が離されてから右及び左のブレーキペダル１５，１６が踏み操作される状態となるので、変速ペダル１２が前進Ｆ（後進Ｒ）から中立位置Ｎに戻りながら、右及び左のブレーキペダル１５，１６が踏み操作される状態となる。 As shown by the solid line C2 in FIG. 4, the operation positions AR, AL (operation values AA) of the right or left brake pedals 15, 16 on the side close to the stepping operation release position A1 are the second set operation position A4 and the first operation position A4. It is assumed that it is between the set operation position A3 (step S6).
As in the previous item [4], when the shift pedal 12 is operated forward F (reverse R) (step S8), the right and left brake pedals 15, 16 are released after the shift pedal 12 is released. Since the pedal is depressed, the right and left brake pedals 15 and 16 are depressed while the shift pedal 12 returns from the forward F (reverse R) to the neutral position N.

この場合、図４の実線Ｃ２に示すように、ステップＳ９と同様に、静油圧式無段変速装置５のトラニオン軸５ａが、変速ペダル１２の操作位置に対応する位置と前進Ｆの設定低速位置Ｆ１（後進Ｒの設定低速位置Ｒ１）との間において操作されるのであり、踏み操作解除位置Ａ１に近い側の右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が第１設定操作位置Ａ３に近づくほど、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの設定低速位置Ｆ１（後進Ｒの設定低速位置Ｒ１）側に操作される。踏み操作解除位置Ａ１に近い側の右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が第１設定操作位置Ａ３になると、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの設定低速位置Ｆ１（後進Ｒの設定低速位置Ｒ１）に到達する（第２減速手段に相当）（ステップＳ１０，Ｓ１１）。   In this case, as indicated by the solid line C2 in FIG. 4, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is located at the position corresponding to the operating position of the shift pedal 12 and the set low speed position of the forward F, as in step S9. The operation position AR, AL (operation value AA) of the right or left brake pedal 15, 16 on the side close to the stepping operation release position A1 is operated between F1 (set low speed position R1 of reverse R). The closer to the first setting operation position A3, the more the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is operated toward the set low speed position F1 for forward F (set low speed position R1 for reverse R). When the operation positions AR and AL (operation values AA) of the right or left brake pedals 15 and 16 on the side close to the stepping operation release position A1 become the first set operation position A3, the trunnion shaft of the hydrostatic continuously variable transmission 5 is obtained. 5a reaches the set low speed position F1 for forward F (set low speed position R1 for reverse R) (corresponding to the second deceleration means) (steps S10 and S11).

ステップＳ１０，Ｓ１１において、変速ペダル１２から足が離されて、変速ペダル１２が前進Ｆ（後進Ｒ）から中立位置Ｎに戻る際、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬに基づく静油圧式無段変速装置５のトラニオン軸５ａの位置に対し、変速ペダル１２の操作位置に対応する位置が中立位置Ｎ側になると（早く中立位置Ｎ側になると）、踏み操作解除位置Ａ１に近い側の右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が無視され、変速ペダル１２の操作位置に基づいて、静油圧式無段変速装置５のトラニオン軸５ａが操作される（早く前進Ｆの設定低速位置Ｆ１（後進Ｒの設定低速位置Ｒ１）に操作される）。   In steps S10 and S11, when the foot is released from the speed change pedal 12 and the speed change pedal 12 returns from the forward F (reverse R) to the neutral position N, the operation positions AR and AL of the right and left brake pedals 15 and 16 are set. When the position corresponding to the operation position of the speed change pedal 12 becomes the neutral position N side (early the neutral position N side) with respect to the position of the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 based, the stepping operation release position A1 The operation positions AR and AL (operation values AA) of the right or left brake pedals 15 and 16 on the side closer to the left are ignored, and the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is determined based on the operation position of the transmission pedal 12. Is operated (moved early to the set low speed position F1 for forward F (set low speed position R1 for reverse R)).

以上の間において、踏み操作解除位置Ａ１に近い側の右又は左のブレーキペダル１５，１６の右又は左のブレーキ１７，１８は解除状態に操作されているのであり、踏み操作解除位置Ａ１から遠い側の右又は左のブレーキペダル１５，１６の右又は左のブレーキ１７，１８は、前項［５］及び図４の一点鎖線Ｃ１に示すように、踏み操作解除位置Ａ１から遠い側の右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬに基づいて制動力を発生する。   In the above period, the right or left brakes 17 and 18 of the right or left brake pedals 15 and 16 on the side close to the stepping operation release position A1 are operated in the release state, and are far from the stepping operation release position A1. The right or left brakes 17 and 18 of the right or left brake pedals 15 and 16 are connected to the right or left side far from the stepping operation release position A1 as shown in the preceding item [5] and the one-dot chain line C1 in FIG. A braking force is generated based on the operation positions AR and AL of the brake pedals 15 and 16.

［７］
次に、右及び左のブレーキペダル１５，１６が踏み操作解除位置Ａ１から制動側限度位置Ａ２に踏み操作される場合（右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが異なる状態）において、静油圧式無段変速装置５と右及び左のブレーキペダル１５，１６との関係の後半について、図５に基づいて説明する。 [7]
Next, when the right and left brake pedals 15 and 16 are stepped from the stepping operation release position A1 to the braking side limit position A2 (the operation positions AR and AL of the right and left brake pedals 15 and 16 are different). The second half of the relationship between the hydrostatic continuously variable transmission 5 and the right and left brake pedals 15 and 16 will be described with reference to FIG.

図４の実線Ｃ２に示すように、踏み操作解除位置Ａ１に近い側の右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が、第１設定操作位置Ａ３と第３設定操作位置Ａ５との間であったとする（ステップＳ６）。
変速レバー１０が前進Ｆに操作されている状態（ステップＳ１２）及び変速ペダル１２が前進Ｆに操作されている状態（ステップＳ１３）では、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの設定低速位置Ｆ１に保持される（ステップＳ１４）。変速ペダル１２が後進Ｒに操作されている状態では（ステップＳ１３）、静油圧式無段変速装置５のトラニオン軸５ａが後進Ｒの設定低速位置Ｒ１に保持される（ステップＳ１５）。 As shown by the solid line C2 in FIG. 4, the operation positions AR, AL (operation values AA) of the right or left brake pedals 15, 16 on the side close to the stepping operation release position A1 are the first set operation position A3 and the third operation position A3. It is assumed that it is between the set operation position A5 (step S6).
In the state where the speed change lever 10 is operated in the forward direction F (step S12) and the state where the speed change pedal 12 is operated in the forward direction F (step S13), the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is moved forward F. Is held at the set low speed position F1 (step S14). In a state where the shift pedal 12 is operated to reverse R (step S13), the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is held at the set low speed position R1 for reverse R (step S15).

図４の実線Ｃ２に示すように、踏み操作解除位置Ａ１に近い側の右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が、第３設定操作位置Ａ５と制動側限度位置Ａ２との間であったとする（ステップＳ６）。この状態では、変速レバー１０及び変速ペダル１２に関係なく、静油圧式無段変速装置５のトラニオン軸５ａが中立位置Ｎに保持される（ステップＳ１６）。   As shown by the solid line C2 in FIG. 4, the operation positions AR and AL (operation values AA) of the right or left brake pedals 15 and 16 on the side close to the stepping operation release position A1 are the third set operation position A5 and the braking side. It is assumed that it is between the limit position A2 (step S6). In this state, regardless of the speed change lever 10 and the speed change pedal 12, the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is held at the neutral position N (step S16).

この場合、図４の一点鎖線Ｃ１に示すように、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）において、第１設定操作位置Ａ３から右及び左のブレーキ１６，１７の制動力が発生し始めるのであり、右及び左のブレーキペダル１５，１６が第１設定操作位置Ａ３から制動側限度位置Ａ２に踏み操作されるほど、右及び左のブレーキ１７，１８の制動力が大きくなっていき、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが制動側限度位置Ａ２になると、右及び左のブレーキ１７，１８の制動力が最大となる。   In this case, as shown by the one-dot chain line C1 in FIG. 4, the right and left brakes 16, 16 from the first set operation position A3 at the operation positions AR, AL (operation value AA) of the right and left brake pedals 15, 16 are shown. The braking force of 17 starts to be generated, and as the right and left brake pedals 15 and 16 are depressed from the first setting operation position A3 to the braking side limit position A2, the braking of the right and left brakes 17 and 18 is controlled. When the power increases and the operation positions AR and AL of the right and left brake pedals 15 and 16 reach the braking side limit position A2, the braking forces of the right and left brakes 17 and 18 become maximum.

［８］
経年劣化等により右及び左のブレーキペダル１５，１６と右及び左のブレーキ１７，１８との間に誤差等が蓄積されると、右及び左のブレーキペダル１５，１６の踏み操作に対して、右及び左のブレーキ１７，１８の制動力が発生し始める右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが変化（移動）することがある。
例えば図４の二点鎖線Ｃ３に示すように、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが第１設定操作位置Ａ３になっても、右及び左のブレーキ１６，１７の制動力が発生せず、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが第１設定操作位置Ａ３を少し越えてから、右及び左のブレーキ１６，１７の制動力が発生するような状態が生じることがある。 [8]
If an error or the like is accumulated between the right and left brake pedals 15 and 16 and the right and left brakes 17 and 18 due to aging, etc., The operation positions AR and AL of the right and left brake pedals 15 and 16 that start to generate braking force of the right and left brakes 17 and 18 may change (move).
For example, as shown by a two-dot chain line C3 in FIG. 4, even if the operation positions AR and AL of the right and left brake pedals 15 and 16 become the first setting operation position A3, the control of the right and left brakes 16 and 17 is suppressed. No power is generated, and the braking forces of the right and left brakes 16 and 17 are generated after the operation positions AR and AL of the right and left brake pedals 15 and 16 slightly exceed the first setting operation position A3. A condition may arise.

この場合、前項［５］及び［７］、図４の実線Ｃ２に示すように、右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）、踏み操作解除位置Ａ１に近い側の右又は左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬ（操作値ＡＡ）が、第１設定操作位置Ａ３と第３設定操作位置Ａ５との間であれば、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの設定低速位置Ｆ１（後進Ｒの設定低速位置Ｒ１）に保持されている。   In this case, as shown in the previous items [5] and [7] and the solid line C2 in FIG. 4, the operation positions AR and AL (operation values AA) of the right and left brake pedals 15 and 16 are close to the step operation release position A1. If the operation positions AR and AL (operation values AA) of the right or left brake pedals 15 and 16 are between the first setting operation position A3 and the third setting operation position A5, the hydrostatic continuously variable transmission The trunnion shaft 5a of the device 5 is held at the set low speed position F1 for forward F (set low speed position R1 for reverse R).

これにより、右及び左のブレーキ１７，１８の制動力が発生し始める右及び左のブレーキペダル１５，１６の操作位置ＡＲ，ＡＬが変化（移動）しても、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの設定低速位置Ｆ１（後進Ｒの設定低速位置Ｒ１）に操作された状態で、右及び左のブレーキ１６，１７の制動力が発生する状態を、確実に生じさせている。   Thereby, even if the operation positions AR and AL of the right and left brake pedals 15 and 16 at which the braking force of the right and left brakes 17 and 18 starts to be generated change (move), the hydrostatic continuously variable transmission 5 When the trunnion shaft 5a is operated to the set low speed position F1 for forward F (set low speed position R1 for reverse R), a state in which the braking force of the right and left brakes 16 and 17 is generated is surely generated. Yes.

［発明の実施の別形態］
前述の［発明を実施するための最良の形態］において、連係ロッド１９に代えて、ワイヤ（図示せず）（連係機構に相当）を使用してもよい。連係ロッド１９及びワイヤを廃止して、右及び左のブレーキ１７，１８を制動側に操作するアクチュエータ（図示せず）（連係機構に相当）を備え、ポテンショメータ２０の検出値に基づいて、アクチュエータにより右及び左のブレーキ１７，１８が制動側に操作されるように構成してもよい。 [Another Embodiment of the Invention]
In the above-mentioned [Best Mode for Carrying Out the Invention], a wire (not shown) (corresponding to a linkage mechanism) may be used instead of the linkage rod 19. Provided with an actuator (not shown) (corresponding to a linkage mechanism) for operating the right and left brakes 17 and 18 to the braking side by eliminating the linkage rod 19 and the wire, and based on the detection value of the potentiometer 20 The right and left brakes 17 and 18 may be operated to the braking side.

前述の［発明を実施するための最良の形態］の図５のステップＳ９，Ｓ１０，Ｓ１１，Ｓ１４，Ｓ１５において、静油圧式無段変速装置５のトラニオン軸５ａが前進Ｆの設定低速位置Ｆ１（後進Ｒの設定低速位置Ｒ１）ではなく、中立位置Ｎに操作されるように構成してもよい。
右及び左の前輪１、右及び左の後輪２に代えて、右及び左のクローラ走行装置（図示せず）（走行装置に相当）を備え、右及び左のクローラ走行装置に右及び左のブレーキ１７，１８を備えた作業車にも、本発明は適用できる。 In Steps S9, S10, S11, S14, and S15 of FIG. 5 of the above-mentioned [Best Mode for Carrying Out the Invention], the trunnion shaft 5a of the hydrostatic continuously variable transmission 5 is set to the forward low-speed setting F1 ( It may be configured to be operated to the neutral position N instead of the reverse low R setting low speed position R1).
Instead of the right and left front wheels 1 and the right and left rear wheels 2, right and left crawler traveling devices (not shown) (corresponding to traveling devices) are provided, and the right and left crawler traveling devices are provided with right and left The present invention can also be applied to work vehicles equipped with the brakes 17 and 18.

農用トラクタの全体側面図Whole side view of agricultural tractor 農用トラクタの全体平面図Overall plan view of agricultural tractor 右及び左のブレーキペダル、右及び左のブレーキ、静油圧式無段変速装置、変速レバー及び変速ペダルの連係状態を示す図The figure which shows the linkage state of a right and left brake pedal, a right and left brake, a hydrostatic continuously variable transmission, a shift lever, and a shift pedal 右及び左のブレーキペダルの操作位置、静油圧式無段変速装置のトラニオン軸、右及び左のブレーキの制動力の関係を示す図The figure which shows the relationship between the operating position of the right and left brake pedals, the trunnion shaft of the hydrostatic continuously variable transmission, and the braking force of the right and left brakes 右及び左のブレーキペダルが踏み操作された際の制御の流れを示す図Diagram showing the flow of control when the right and left brake pedals are depressed

符号の説明Explanation of symbols

２ 右及び左の走行装置
５ 走行用の無段変速装置
１５ 右のブレーキペダル
１６ 左のブレーキペダル
１７ 右のブレーキ
１８ 左のぶれーき
１９ 連係機構
２０ 操作位置センサー
Ａ１ 踏み操作解除位置
Ａ２ 制動側限度位置
Ａ３ 設定操作位置
ＡＲ 右のブレーキペダルの操作位置
ＡＬ 左のブレーキペダルの操作位置
Ｎ 停止位置 2 right and left traveling devices 5 continuously variable transmission 15 for traveling 15 right brake pedal 16 left brake pedal 17 right brake 18 left brake 19 linkage mechanism 20 operation position sensor A1 step operation release position A2 braking side Limit position A3 Setting operation position AR Right brake pedal operation position AL Left brake pedal operation position N Stop position

Claims (2)

人為的に操作される右及び左のブレーキペダルと、右及び左の走行装置用の右及び左のブレーキとを備え、
前記右のブレーキペダルが踏み操作されると連係機構を介して右のブレーキが制動側に操作されるように構成し、前記左のブレーキペダルが踏み操作されると連係機構を介して左のブレーキが制動側に操作されるように構成して、
停止位置から高速側に操作自在な走行用の無段変速装置と、前記右及び左のブレーキペダルの操作位置を検出する操作位置センサーとを備えて、
前記右及び左のブレーキペダルの操作位置が同じ状態で、前記右及び左のブレーキペダルが踏み操作されると、前記走行用の無段変速装置を停止位置側に操作する第１減速手段を備え、
前記右及び左のブレーキペダルの操作位置が異なる状態で、前記右及び左のブレーキペダルが踏み操作されると、踏み操作解除位置に近い側の右又は左のブレーキペダルの操作位置に基づき、踏み操作解除位置に近い側の右又は左のブレーキペダルの操作位置が制動側限度位置に近づくほど、前記走行用の無段変速装置を停止位置側に操作する第２減速手段を備えてある作業車。 Artificially operated right and left brake pedals and right and left brakes for right and left travel devices,
The right brake is operated to the braking side via the linkage mechanism when the right brake pedal is depressed, and the left brake via the linkage mechanism when the left brake pedal is depressed. Is configured to be operated to the braking side,
A continuously variable transmission for travel that can be operated from the stop position to the high speed side, and an operation position sensor that detects operation positions of the right and left brake pedals,
A first reduction means for operating the continuously variable transmission for travel to a stop position when the right and left brake pedals are stepped on when the operation positions of the right and left brake pedals are the same; ,
If the right and left brake pedals are stepped on in a state where the right and left brake pedals are operated at different positions, the stepping on the right or left brake pedal on the side closer to the stepping release position is performed. A work vehicle provided with second reduction means for operating the travel continuously variable transmission toward the stop position as the operation position of the right or left brake pedal closer to the operation release position approaches the brake side limit position. . 踏み操作解除位置と制動側限度位置との間の踏み操作範囲において、踏み操作解除位置と制動側限度位置との間に設定操作位置を設定し、前記右及び左のブレーキペダルの操作位置が踏み操作解除位置と設定操作位置との間であると、前記右及び左のブレーキが解除状態に操作され、前記右及び左のブレーキペダルの操作位置が設定操作位置から制動側限度位置に操作されるほど、右及び左のブレーキが解除状態から制動側に操作されるように構成すると共に、
前記右及び左のブレーキペダルの操作位置が異なる状態で、前記右及び左のブレーキペダルが踏み操作されると、踏み操作解除位置に近い側の右又は左のブレーキペダルの操作位置に基づき、前記踏み操作解除位置と設定操作位置との間において、踏み操作解除位置に近い側の右又は左のブレーキペダルの操作位置が設定操作位置に近づくほど、前記走行用の無段変速装置を停止位置側に操作するように、前記第２減速手段を構成してある請求項１に記載の作業車。 In the step operation range between the step operation release position and the brake side limit position, a set operation position is set between the step operation release position and the brake side limit position, and the operation positions of the right and left brake pedals are When the position is between the operation release position and the set operation position, the right and left brakes are operated in the released state, and the operation position of the right and left brake pedals is operated from the set operation position to the braking side limit position. The right and left brakes are configured to be operated from the released state to the braking side,
When the right and left brake pedals are stepped on in a state where the right and left brake pedals are operated at different positions, based on the right or left brake pedal operating position on the side close to the stepping operation release position, As the operation position of the right or left brake pedal closer to the stepping operation release position approaches the setting operation position between the stepping operation release position and the setting operation position, the travel continuously variable transmission is moved to the stop position side. The work vehicle according to claim 1, wherein the second speed reducing unit is configured to operate the vehicle.
JP2007231486A 2007-09-06 2007-09-06 Work vehicle Active JP5123617B2 (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014029215A (en) * 2013-10-31 2014-02-13 Kubota Corp Working vehicle
US9283951B2 (en) 2010-01-21 2016-03-15 Kubota Corporation Speed change system for work vehicle
JP2016065636A (en) * 2014-09-24 2016-04-28 株式会社クボタ Harvesting machine

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JPS61125834U (en) * 1985-01-25 1986-08-07
JPH1038076A (en) * 1996-07-26 1998-02-13 Mitsubishi Agricult Mach Co Ltd Interlocking mechanism of operating lever and brake pedal in static hydraulic transmission
JP2001027319A (en) * 1999-07-14 2001-01-30 Hitachi Constr Mach Co Ltd Hydraulic closed circuit drive wheel type vehicle
JP2002310296A (en) * 2001-04-13 2002-10-23 Ishikawajima Shibaura Mach Co Ltd Speed control mechanism for work vehicle

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Publication number Priority date Publication date Assignee Title
JPS61125834U (en) * 1985-01-25 1986-08-07
JPH1038076A (en) * 1996-07-26 1998-02-13 Mitsubishi Agricult Mach Co Ltd Interlocking mechanism of operating lever and brake pedal in static hydraulic transmission
JP2001027319A (en) * 1999-07-14 2001-01-30 Hitachi Constr Mach Co Ltd Hydraulic closed circuit drive wheel type vehicle
JP2002310296A (en) * 2001-04-13 2002-10-23 Ishikawajima Shibaura Mach Co Ltd Speed control mechanism for work vehicle

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9283951B2 (en) 2010-01-21 2016-03-15 Kubota Corporation Speed change system for work vehicle
JP2014029215A (en) * 2013-10-31 2014-02-13 Kubota Corp Working vehicle
JP2016065636A (en) * 2014-09-24 2016-04-28 株式会社クボタ Harvesting machine

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