JP3549648B2 - Traveling drive for self-propelled work vehicles - Google Patents

Traveling drive for self-propelled work vehicles Download PDF

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Publication number
JP3549648B2
JP3549648B2 JP32647395A JP32647395A JP3549648B2 JP 3549648 B2 JP3549648 B2 JP 3549648B2 JP 32647395 A JP32647395 A JP 32647395A JP 32647395 A JP32647395 A JP 32647395A JP 3549648 B2 JP3549648 B2 JP 3549648B2
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Prior art keywords
traveling
displacement hydraulic
power
shaft
speed
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JP32647395A
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JPH09142164A (en
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佐一郎 森田
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セイレイ工業株式会社
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  • Motor Power Transmission Devices (AREA)
  • Arrangement And Driving Of Transmission Devices (AREA)
  • Non-Deflectable Wheels, Steering Of Trailers, Or Other Steering (AREA)
  • Transmission Devices (AREA)

Description

【0001】
【発明の属する技術分野】
本発明は、クローラ式走行装置を具備した自走式作業車の走行駆動装置に関する。
【0002】
【従来の技術】
従来、左右一対のクローラ式の走行装置を具備し、原動機からの動力によって走行駆動される自走式作業車では、上記原動機と走行装置との間に、噛合歯車群で構成された機械式動力伝達機構や、原動機に連動連結した油圧ポンプで左右走行部に連動連結した油圧モータを駆動する油圧式動力伝達機構が介設されており、左右の走行装置の走行速度を同一にして直進させ、走行速度を異ならせて進行方向を操向するようにしている。
【0003】
【発明が解決しようとする課題】
ところが、上記機械式動力伝達機構では、デフを介して左右走行装置に動力を分配しているため、左右走行部が受ける走行抵抗の差異によって左右の走行速度に差異が生ずるため直進性が悪く、また、旋回に際しては、左右走行装置の一方の駆動を停止して制動し、他方の走行装置のみ駆動するため、旋回が急激に行われて圃場面を傷めるという問題がある。
【0004】
また、油圧式動力伝達機構の場合も、1個の油圧ポンプで左右走行部の油圧モータを駆動するので、上記同様に左右走行抵抗の差異によって直進性が悪くなるという問題がある。
【0005】
【課題を解決するための手段】
そこで、本発明では、左右一対のクロ−ラ式走行装置を具備し、原動機からの動力により上記走行装置を駆動し、しかも、左右走行装置への駆動速度を異ならせて進行方向を操向すべく構成した自走式作業車において、原動機に左右可変容量型油圧ポンプを連動連結し、左右可変容量型油圧ポンプにそれぞれ左右定容量型油圧モ−タを連動連結し、左右定容量型油圧モ−タにそれぞれ左右走行部駆動系を連動連結して、左右走行部駆動系の上流側に動力取出し軸をワンウエイクラッチを介して連動連結し、左右走行駆動系のいずれか回転の速い方から動力取出し軸に動力が伝達されるようにしたことを特徴とする自走式作業車の走行駆動装置を提供せんとするものである。
【0006】
そして、本発明装置は、上記のように構成したことによって、自走式作業車の走行速度を前進から後進に渉って無段階に変速することができ、しかも、上記ポンプの吐出量を左右異ならせることで、緩旋回から急旋回に渉ってスム−ズな操向を行うことができる。また、動力取出し軸は、左右一対のクロ−ラ式走行装置による機体の左旋回、又は、右旋回に関係なく、回転速度の速い方から出力できるために、安定した動力の取出しが可能となって、同動力取出し軸により作動される作業部を安定作動させることができ、同作業部の作業機能を良好に確保することができる

【0007】
【発明の実施の形態】
本発明の実施の形態について図面を参照して説明する。
【0008】
図1は、本発明に係る走行駆動装置Aの構成を示しており、1は入力軸であって、一端をベルト伝動機構2を介してエンジン(図示せず)に連動連結し、他端をポンプ駆動用噛合歯車3を介して左右可変容量型油圧ポンプ4L,4R とチャージポンプ5とに連動連結している。
【0009】
上記左右可変容量型油圧ポンプ4L,4R は、それぞれ左右走行部駆動系L,R の始端である左右定容量型油圧モータ6L,6R に連通連結している。
【0010】
左右走行部駆動系L,R は対称的に構成されているので、左走行部駆動系Lについて説明する。
【0011】
左定容量型油圧モータ6Lはそれぞれ左モータ軸歯車7Lと左第2速原動歯車11L との噛合を介して左連結クラッチ軸8Lに連動連結している。
【0012】
左連結クラッチ軸8Lには、それぞれ左第1速原動歯車10L と左第2速原動歯車11L とが形成されており、上記左第1速原動歯車10L と左第1速受動歯車12L との噛合、左第2速原動歯車11L と左第2速受動歯車13L との噛合、左第1速クラッチ14L 及び左第2速クラッチ15L を介し左変速軸16L に連動連結して左副変速部17L を構成している。
【0013】
左変速軸16L には、それぞれ左駆動歯車18L が形成されており、左受動歯車19L との噛合を介して左中間軸20L に連動連結し、左中間軸20L は左駆動歯車群21L を介して、左走行部を駆動する左スプロケット22L に連動連結している。
【0014】
図中、7Rは右モータ軸歯車、8Rは右連結クラッチ軸、10R は右第1速原動歯車、11R は右第2速原動歯車、12R は右第1速受動歯車、13R は右第2速受動歯車、14R は右第1速クラッチ、15R は右第2速クラッチ、16R は右変速軸、17R は右副変速部、18R は右駆動歯車、19R は右受動歯車、20R は右中間軸、21R は右駆動歯車群、22R は右スプロケットである。
【0015】
特に、前記左右副変速部17L,17R の上流側に位置する左右連結クラッチ軸8L,8R の間には、連結部Mとしての連結クラッチ9が跨設されており、同連結クラッチ9の結合により左右連結クラッチ軸8L,8R を同一速度で回動させ、結合解除により左右連結クラッチ軸8L,8R を異なる速度で回動できるようにしている。
【0016】
このように、左右副変速部17L,17R の上流側に連結部Mとしての連結クラッチ9を設けたことで、同連結クラッチ9が負担するトルクが小さくなり、同連結クラッチ9を小形化することができる。
【0017】
図中、30は動力取出し軸であって一端に動力取出しプーリ31を嵌着しており、同動力取出し軸30は動力取出し用歯車群32とワンウエイクラッチ33とを介して前記入力軸1と連動連結すると共に、動力取出し軸30に形成した左右動力取出し用受動歯車34L,34R と左右モータ軸歯車7L,7R との噛合を介し、左右可変容量型油圧ポンプ4L,4R にそれぞれ連動連結している。
【0018】
かかる構成により、動力取出し軸30は、動力取出し用歯車群32及び左右動力取出し用受動歯車34L,34R から伝達される動力の回転数の大きい方から駆動されることになり、車両の停止中でも動力取出しプーリ31から出力することができる。
【0019】
本発明の実施形態は上記のように構成されており、左右可変容量型油圧ポンプ4L,4R の吐出量を一緒に変化させて走行速度を変更したり、左右第1速クラッチ14L,14R 及び左右第2速クラッチ15L,15R を操作して、走行速度や駆動力を変更することができる。
【0020】
また、連結クラッチ9を結合することで、左右走行抵抗の差異にかかわらず直進性を高めることができ、連結クラッチ9の結合を解除した状態で、左右可変容量型油圧ポンプ4L,4R の吐出量を左右異ならせることにより、緩旋回から急旋回に渉って円滑な操向を行うことができる。
【0021】
図2は、動力取出しプーリ31を示しており、同動力取出しプーリ31は、所定間隔を保持して介装した内外ベアリング40,41 によってミッションケース42から突出した動力取出し軸30の端部に軸支されており、上記間隔内に介装したワンウエイクラッチ43によって、動力取出し軸30と動力取出しプーリ31とを連動連結しており、間隔を設けて配設した2個のベアリングで動力取出しプーリ31のラジアル荷重を支持するので、多数のVベルトを巻回しても同動力取出しプーリ31が安定し、ワンウエイクラッチ43の作動が確実になり、動力伝達を確実にすることができる。図2中、44はベアリング支持筒体、45はベアリング支持筒体44を動力取出し軸30に固定するためのキー、46は止め輪、47はワンウエイクラッチ43の外輪に動力取出しプーリ31を取付けるための六角穴付きボルト、48はオイルシール、49はキャップである。
【0022】
【発明の効果】
本発明によれば次のような効果を得ることができる。
【0023】
左右一対のクロ−ラ式走行装置を具備し、原動機からの動力により上記走行装置を駆動し、しかも、左右走行装置への駆動速度を異ならせて進行方向を操向すべく構成した自走式作業車において、原動機に左右可変容量型油圧ポンプを連動連結し、左右可変容量型油圧ポンプにそれぞれ左右定容量型油圧モ−タを連動連結し、左右定容量型油圧モ−タにそれぞれ左右走行部駆動系を連動連結して、左右走行部駆動系の上流側に動力取出し軸をワンウエイクラッチを介して連動連結し、左右走行駆動系のいずれか回転の速い方から動力取出し軸に動力が伝達されるようにしたことによって、自走式作業車の走行速度を前進から後進に渉って無段階に変速することができ、しかも、上記ポンプの吐出量を左右異ならせることで、緩旋回から急旋回に渉ってスム−ズな操向を行うことができる。また、動力取出し軸は、左右一対のクロ−ラ式走行装置による機体の左旋回、又は、右旋回に関係なく、回転速度の速い方から出力できるために、安定した動力の取出しが可能となって、同動力取出し軸により作動される作業部を安定作動させることができ、同作業部の作業機能を良好に確保することができる

【図面の簡単な説明】
【図1】本発明走行駆動装置の構成を示す展開説明図。
【図2】動力取出しプーリの断面説明図。
【符号の説明】
M 連結部
L 左走行部駆動系
R 右走行部駆動系
4L 左可変容量型油圧ポンプ
4R 右可変容量型油圧ポンプ
6L 左定容量型油圧モータ
6R 右定容量型油圧モータ
17L 左副変速部
17R 右副変速部
[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a traveling drive device for a self-propelled work vehicle including a crawler traveling device.
[0002]
[Prior art]
Conventionally, a self-propelled work vehicle having a pair of left and right crawler-type traveling devices and driven to travel by power from a prime mover has a mechanical power train composed of a meshing gear group between the prime mover and the traveling device. A transmission mechanism and a hydraulic power transmission mechanism that drives a hydraulic motor interlocked to the left and right traveling units with a hydraulic pump interlocked to the prime mover are interposed, and the traveling speed of the left and right traveling devices is made the same and go straight, The traveling speed is varied to steer the traveling direction.
[0003]
[Problems to be solved by the invention]
However, in the mechanical power transmission mechanism, since power is distributed to the left and right traveling devices via the differential, a difference in traveling resistance received by the left and right traveling units causes a difference in left and right traveling speeds, so that straightness is poor, Further, when turning, one of the left and right traveling devices is stopped and braked, and only the other traveling device is driven. Therefore, there is a problem that the turning is rapidly performed and the field scene is damaged.
[0004]
Also, in the case of a hydraulic power transmission mechanism, since a single hydraulic pump drives the hydraulic motors of the left and right traveling units, there is a problem that the straightness is deteriorated due to the difference in the left and right traveling resistance as described above.
[0005]
[Means for Solving the Problems]
Therefore, in the present invention, a pair of left and right crawler-type traveling devices are provided, the traveling device is driven by power from a prime mover, and the traveling direction is steered by changing the driving speed to the left and right traveling devices. The left and right variable displacement hydraulic pumps are linked to the prime mover and the left and right constant displacement hydraulic motors are linked to the right and left variable displacement hydraulic pumps. -The left and right traveling unit drive systems are linked to each other, and the power take-off shaft is linked to the upstream side of the left and right traveling unit drive systems via a one-way clutch. It is an object of the present invention to provide a traveling drive device for a self-propelled work vehicle , wherein power is transmitted to a take-out shaft .
[0006]
The device of the present invention can continuously change the traveling speed of the self-propelled work vehicle from forward movement to reverse movement by having the above-described configuration, and furthermore, can control the discharge amount of the pump from left to right. By making them different, smooth steering can be performed from gentle turning to sharp turning. In addition, the power take-off shaft can output power from the one with the faster rotation speed regardless of the left or right turn of the body by the pair of left and right crawler traveling devices, so that stable power take-out is possible. As a result, the working unit operated by the power take-out shaft can be operated stably, and the working function of the working unit can be ensured well .

[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings.
[0008]
FIG. 1 shows the configuration of a traveling drive device A according to the present invention, wherein 1 is an input shaft, one end of which is operatively connected to an engine (not shown) via a belt transmission mechanism 2 and the other end thereof. The right and left variable displacement hydraulic pumps 4L, 4R and the charge pump 5 are linked to each other via a pump drive meshing gear 3.
[0009]
The right and left variable displacement hydraulic pumps 4L and 4R are connected to left and right constant displacement hydraulic motors 6L and 6R, which are the starting ends of the left and right traveling unit drive systems L and R, respectively.
[0010]
Since the left and right traveling unit drive systems L and R are configured symmetrically, the left traveling unit drive system L will be described.
[0011]
The left constant displacement hydraulic motor 6L is interlockingly connected to the left connecting clutch shaft 8L via meshing of a left motor shaft gear 7L and a left second speed driving gear 11L.
[0012]
A left first-speed driving gear 10L and a left second-speed driving gear 11L are formed on the left coupling clutch shaft 8L, respectively, and mesh with the left first-speed driving gear 10L and the left first-speed passive gear 12L. , The left second speed driving gear 11L and the left second speed passive gear 13L mesh with each other, and are operatively connected to the left speed change shaft 16L via the left first speed clutch 14L and the left second speed clutch 15L to connect the left subtransmission portion 17L. Make up.
[0013]
A left drive gear 18L is formed on each of the left transmission shafts 16L, and is operatively connected to a left intermediate shaft 20L via meshing with a left passive gear 19L, and the left intermediate shaft 20L is connected via a left drive gear group 21L. , And a left sprocket 22L for driving the left running section.
[0014]
In the figure, 7R is a right motor shaft gear, 8R is a right coupling clutch shaft, 10R is a right first speed driving gear, 11R is a right second speed driving gear, 12R is a right first speed passive gear, and 13R is a right second speed. Passive gear, 14R is right first speed clutch, 15R is right second speed clutch, 16R is right transmission shaft, 17R is right auxiliary transmission, 18R is right driving gear, 19R is right passive gear, 20R is right intermediate shaft, 21R is a right drive gear group, and 22R is a right sprocket.
[0015]
In particular, a connecting clutch 9 as a connecting portion M is provided between the left and right connecting clutch shafts 8L and 8R located upstream of the left and right sub-transmission portions 17L and 17R. The left and right connecting clutch shafts 8L and 8R are rotated at the same speed, and the left and right connecting clutch shafts 8L and 8R can be rotated at different speeds by releasing the connection.
[0016]
Thus, by providing the connecting clutch 9 as the connecting portion M on the upstream side of the left and right auxiliary transmission portions 17L, 17R, the torque borne by the connecting clutch 9 is reduced, and the connecting clutch 9 can be downsized. Can be.
[0017]
In the figure, reference numeral 30 denotes a power take-out shaft, and a power take-out pulley 31 is fitted at one end thereof. The power take-out shaft 30 is interlocked with the input shaft 1 via a power take-out gear group 32 and a one-way clutch 33. In addition to being connected, the right and left motor shaft gears 7L and 7R are interlockingly connected to the left and right variable displacement hydraulic pumps 4L and 4R, respectively, via meshing of the left and right power take-off passive gears 34L and 34R formed on the power take-out shaft 30. .
[0018]
With this configuration, the power take-out shaft 30 is driven from the larger rotational speed of the power transmitted from the power take-out gear group 32 and the left and right power take-up passive gears 34L, 34R. It can be output from the take-out pulley 31.
[0019]
The embodiment of the present invention is configured as described above, and changes the running speed by changing the discharge amounts of the left and right variable displacement hydraulic pumps 4L and 4R together, and changes the left and right first speed clutches 14L and 14R and the left and right first speed clutches 14L and 14R. The traveling speed and the driving force can be changed by operating the second speed clutches 15L and 15R.
[0020]
Further, by connecting the connecting clutch 9, the straightness can be improved irrespective of the difference between the left and right running resistances, and the discharge amount of the left and right variable displacement hydraulic pumps 4L, 4R can be increased in a state where the connecting clutch 9 is released. By making the left and right different, smooth steering can be performed from gentle turning to sharp turning.
[0021]
FIG. 2 shows a power take-off pulley 31. The power take-off pulley 31 is attached to an end of a power take-out shaft 30 protruding from a transmission case 42 by inner and outer bearings 40 and 41 interposed at a predetermined interval. The power take-off shaft 30 and the power take-off pulley 31 are interlockingly connected by a one-way clutch 43 interposed within the above-mentioned space, and the power take-off pulley 31 is provided by two bearings arranged at intervals. , The power take-off pulley 31 becomes stable even when a large number of V-belts are wound, the one-way clutch 43 operates reliably, and power transmission can be ensured. 2, reference numeral 44 denotes a bearing support cylinder, 45 denotes a key for fixing the bearing support cylinder 44 to the power take-out shaft 30, 46 denotes a retaining ring, and 47 denotes a power take-off pulley 31 attached to the outer ring of the one-way clutch 43. Is a hexagon socket head cap screw, 48 is an oil seal, and 49 is a cap.
[0022]
【The invention's effect】
According to the present invention, the following effects can be obtained.
[0023]
A self-propelled type equipped with a pair of left and right crawler-type traveling devices that drives the traveling device by the power from the prime mover and steers the traveling direction by changing the driving speed to the left and right traveling devices. In the work vehicle, the left and right variable displacement hydraulic pumps are linked to the prime mover, the left and right variable displacement hydraulic pumps are linked to the left and right constant displacement hydraulic motors, respectively, and the left and right constant displacement hydraulic motors travel left and right respectively. The power drive shaft is linked to the upstream of the left and right traveling unit drive system via a one-way clutch, and power is transmitted to the power take-off shaft from the faster rotating one of the left and right drive systems. By doing so, the traveling speed of the self-propelled work vehicle can be steplessly changed from forward to reverse, and by making the discharge amount of the pump different from left to right, Sharp turn Wataru' Te Sum - can be carried out's of steering. In addition, the power take-off shaft can output power from the one with the faster rotation speed regardless of the left or right turn of the body by the pair of left and right crawler traveling devices, so that stable power take-out is possible. As a result, the working unit operated by the power take-out shaft can be operated stably, and the working function of the working unit can be ensured well .

[Brief description of the drawings]
FIG. 1 is a development explanatory view showing a configuration of a traveling drive device of the present invention.
FIG. 2 is an explanatory sectional view of a power take-off pulley.
[Explanation of symbols]
M Connecting part L Left traveling part drive system R Right traveling part drive system 4L Left variable displacement hydraulic pump 4R Right variable displacement hydraulic pump 6L Left constant displacement hydraulic motor 6R Right constant displacement hydraulic motor 17L Left auxiliary transmission 17R Right Sub transmission section

Claims (1)

左右一対のクロ−ラ式走行装置を具備し、原動機からの動力により上記走行装置を駆動し、しかも、左右走行装置への駆動速度を異ならせて進行方向を操向すべく構成した自走式作業車において、原動機に左右可変容量型油圧ポンプ(4L)(4R)を連動連結し、左右可変容量型油圧ポンプ(4L)(4R)にそれぞれ左右定容量型油圧モ−タ(6L)(6R)を連動連結し、左右定容量型油圧モ−タ(6L)(6R)にそれぞれ左右走行部駆動系(L)(R)を連動連結して、左右走行部駆動系 ( )( ) の上流側に動力取出し軸 ( 30 ) をワンウエイクラッチ ( 33 )( 33 ) を介して連動連結し、左右走行駆動系 ( )( ) のいずれか回転の速い方から動力取出し軸 ( 30 ) に動力が伝達されるようにしたことを特徴とする自走式作業車の走行駆動装置。A self-propelled type equipped with a pair of left and right crawler-type traveling devices that drives the traveling device by the power from the prime mover and steers the traveling direction by changing the driving speed to the left and right traveling devices. In the work vehicle, the right and left variable displacement hydraulic pumps (4L) and (4R) are interlocked to the prime mover, and the left and right constant displacement hydraulic motors (6L) and (6R) are respectively connected to the left and right variable displacement hydraulic pumps (4L) and (4R). ) And the right and left constant displacement hydraulic motors (6L) and (6R) are connected to the left and right traveling unit drive systems ( L ) and ( R ) , respectively , to provide the left and right traveling unit drive systems ( L ) and ( R ). upstream one-way clutch power take-off shaft (30) to (33) (33) is interlockingly connected through the right and left travel drive system (L) a power takeoff shaft from the side fast rotating either (R) (30) A traveling drive device for a self-propelled work vehicle , wherein power is transmitted to the vehicle.
JP32647395A 1995-11-20 1995-11-20 Traveling drive for self-propelled work vehicles Expired - Fee Related JP3549648B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP32647395A JP3549648B2 (en) 1995-11-20 1995-11-20 Traveling drive for self-propelled work vehicles

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Application Number Priority Date Filing Date Title
JP32647395A JP3549648B2 (en) 1995-11-20 1995-11-20 Traveling drive for self-propelled work vehicles

Publications (2)

Publication Number Publication Date
JPH09142164A JPH09142164A (en) 1997-06-03
JP3549648B2 true JP3549648B2 (en) 2004-08-04

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JP32647395A Expired - Fee Related JP3549648B2 (en) 1995-11-20 1995-11-20 Traveling drive for self-propelled work vehicles

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Publication number Priority date Publication date Assignee Title
JP6523946B2 (en) * 2015-12-25 2019-06-05 株式会社クボタ Power transmission mechanism
KR102376683B1 (en) * 2016-06-29 2022-03-21 가부시끼 가이샤 구보다 Power transmission apparatus

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