JPH0263973A - Rear-wheel steering mechanism - Google Patents
Rear-wheel steering mechanismInfo
- Publication number
- JPH0263973A JPH0263973A JP21617688A JP21617688A JPH0263973A JP H0263973 A JPH0263973 A JP H0263973A JP 21617688 A JP21617688 A JP 21617688A JP 21617688 A JP21617688 A JP 21617688A JP H0263973 A JPH0263973 A JP H0263973A
- Authority
- JP
- Japan
- Prior art keywords
- wheel steering
- rear wheel
- shaft
- valve
- valve element
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000007246 mechanism Effects 0.000 title claims abstract description 36
- 230000007935 neutral effect Effects 0.000 abstract description 37
- 238000006073 displacement reaction Methods 0.000 abstract description 10
- 230000033001 locomotion Effects 0.000 description 8
- 230000008859 change Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D7/00—Steering linkage; Stub axles or their mountings
- B62D7/06—Steering linkage; Stub axles or their mountings for individually-pivoted wheels, e.g. on king-pins
- B62D7/14—Steering linkage; Stub axles or their mountings for individually-pivoted wheels, e.g. on king-pins the pivotal axes being situated in more than one plane transverse to the longitudinal centre line of the vehicle, e.g. all-wheel steering
- B62D7/15—Steering linkage; Stub axles or their mountings for individually-pivoted wheels, e.g. on king-pins the pivotal axes being situated in more than one plane transverse to the longitudinal centre line of the vehicle, e.g. all-wheel steering characterised by means varying the ratio between the steering angles of the steered wheels
- B62D7/1554—Steering linkage; Stub axles or their mountings for individually-pivoted wheels, e.g. on king-pins the pivotal axes being situated in more than one plane transverse to the longitudinal centre line of the vehicle, e.g. all-wheel steering characterised by means varying the ratio between the steering angles of the steered wheels comprising a fluid interconnecting system between the steering control means of the different axles
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Steering-Linkage Mechanisms And Four-Wheel Steering (AREA)
Abstract
Description
【発明の詳細な説明】
[産業上の利用分野]
本発明は4輪操舵車両の後輪操舵機構に関するものであ
る。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rear wheel steering mechanism for a four-wheel steering vehicle.
し従来の技術〕
特開昭59−6171号公報に開示されるように、前輪
舵角に対応する電気信号を入力とする電子υ1tll装
置の出力により、サーボ制御弁ないし油量制御弁を駆動
し、これにより後輪操舵アクチュエータの油圧回路を制
御するとともに、後輪操舵アクチュエータの動作量を電
気的に検出して電子制御装置へフィードバックするもの
が知られている。この後輪操舵機構では、サーボ制御弁
ないし油量調節弁を駆動するために、前輪舵角に対応す
る機械的変位凹を電気量に変換し、この電気量に基づい
て回連とする後輪舵角を演算し、この演算結果に基づく
電気量をアクチュエータにより機械的変位惜に変換する
という制′n動作を伴い、余分な電気l−礪械吊変換が
加わり、構造が複雑であり、コストも高くなる。[Prior art] As disclosed in Japanese Unexamined Patent Publication No. 59-6171, a servo control valve or an oil flow control valve is driven by the output of an electronic υ1tll device that receives an electric signal corresponding to the front wheel steering angle as input. It is known that the hydraulic circuit of the rear wheel steering actuator is thereby controlled, and the amount of operation of the rear wheel steering actuator is electrically detected and fed back to an electronic control device. In this rear wheel steering mechanism, in order to drive a servo control valve or an oil flow control valve, the mechanical displacement corresponding to the front wheel steering angle is converted into an electrical quantity, and the rear wheels are rotated based on this electrical quantity. It involves a restrictive operation of calculating the steering angle and converting the electric quantity based on the calculation result into a mechanical displacement by an actuator, and an extra electric power-mechanical suspension conversion is added, making the structure complicated and increasing the cost. It also becomes more expensive.
一方、特開昭61−132469号公報に開示される後
輪操舵機構では、前輪舵角の変化をケーブルを介して後
輪操舵アクチュエータのサーボ制御弁に連結しているの
で、電気的構成部材を含まない点でコストが節減される
が、前輪操舵部材と後輪操舵部材を連結するケーブルが
、後輪操舵の原動力となる力を伝達する役割を果すので
、高強度のケーブルが必要とされる。また、後輪操舵用
油圧を前輪操舵系から取り出しているので、後輪の操舵
時と非操舵時ではハンドルの操作力が変動し、運転者に
違和感を与える。On the other hand, in the rear wheel steering mechanism disclosed in Japanese Unexamined Patent Publication No. 61-132469, changes in the front wheel steering angle are connected to the servo control valve of the rear wheel steering actuator via a cable. Although the cost is saved by not including the front wheel steering member and the rear wheel steering member, a high-strength cable is required because the cable that connects the front wheel steering member and the rear wheel steering member plays the role of transmitting the force that is the driving force for rear wheel steering. . Furthermore, since the rear wheel steering hydraulic pressure is extracted from the front wheel steering system, the operating force of the steering wheel varies between when the rear wheels are being steered and when the rear wheels are not being steered, giving the driver a sense of discomfort.
[発明が解決しようとする問題点1
本発明の目的は身雑て高価な1子制叩装置を必要とせず
、機械的強度上に問題がなく、後輪操舵部材の動作が機
械的にフィードバックされる差動制御弁により、後輪操
舵アクチュエータが制御される後輪操舵R1Rを提供す
ることにある。[Problem to be Solved by the Invention 1] The purpose of the present invention is to eliminate the need for a complicated and expensive single-child control device, to avoid mechanical strength problems, and to provide mechanical feedback to the operation of the rear wheel steering member. An object of the present invention is to provide a rear wheel steering R1R in which a rear wheel steering actuator is controlled by a differential control valve.
[問題を解決するための手段1
上記目的を達成するために、本発明の構成は油圧源を差
動制御弁を経て後輪ナックルを駆動する後輪操舵アクチ
ュエータに接続し、ハンドルの切り角に関連しで回転す
る駆動軸により差io制御弁の弁要素を往動し、後輪ナ
ックルにケーブルを介して運動連結する従動軸により弁
要素を復動させるようにしたものである。[Means for Solving the Problem 1] In order to achieve the above object, the configuration of the present invention connects a hydraulic power source to a rear wheel steering actuator that drives the rear wheel knuckle via a differential control valve, and adjusts the turning angle of the steering wheel. The valve element of the differential IO control valve is moved forward by a relatedly rotating drive shaft, and the valve element is moved backward by a driven shaft that is movably connected to the rear wheel knuckle via a cable.
[作用1
例えば、ハンドル41を右へ切ると、前輪舵取は構30
の出力軸29に連vJ連結する前輪ナックル38が支軸
34を中心として回動され、前輪40が右へ隔向される
。同時に、出力軸29に運動連結する@1つの回転が直
接または舵角特性徐変機構Aを介して、差動制御弁Bの
弁要素を往動させる駆動軸24へ伝達される。油圧ポン
プ26から圧油が管72.75、差動制御弁Bを経て、
管76から後輪操舵アクチュエータFの室89へ入り、
ピストン56と一緒にタイロッド65が右へ駆動され、
後輪ナックル6つが支軸70を中心として回動され、後
輪71が左I\偏向される。後輪操舵アクチュエータF
の室9′1の油は、管80、差動制御弁B、管79.7
7を経て油タンク28へ戻される。[Effect 1 For example, when the steering wheel 41 is turned to the right, the front wheel steering is
A front wheel knuckle 38 connected to the output shaft 29 of the front wheel VJ is rotated about the support shaft 34, and the front wheel 40 is moved to the right. At the same time, the rotation of the output shaft 29 that is movably coupled to the output shaft 29 is transmitted directly or via the steering angle characteristic gradual change mechanism A to the drive shaft 24 that causes the valve element of the differential control valve B to move forward. Pressure oil from the hydraulic pump 26 passes through the pipe 72.75 and the differential control valve B.
enters the chamber 89 of the rear wheel steering actuator F from the pipe 76;
The tie rod 65 is driven to the right together with the piston 56,
The six rear wheel knuckles are rotated about the support shaft 70, and the rear wheel 71 is deflected to the left. Rear wheel steering actuator F
The oil in the chamber 9'1 is supplied to the pipe 80, the differential control valve B, and the pipe 79.7.
7 and is returned to the oil tank 28.
タイロッド65が移動すると、この機械的変位量はケー
ブル50を経て差動制御弁Bの弁要素を復動させる従動
軸6へ伝達される。こうして、差動制御弁Bの弁要素が
中立位置へ戻ると、管7579に対し管76.80が′
a断され、その位置に後輪操舵アクチュエータFが停止
し、後輪71がその舵角に保持される。When the tie rod 65 moves, this mechanical displacement is transmitted via the cable 50 to the driven shaft 6 which causes the valve element of the differential control valve B to move back. Thus, when the valve element of differential control valve B returns to the neutral position, pipe 76.80 is
a, the rear wheel steering actuator F stops at that position, and the rear wheels 71 are held at that steering angle.
差動制御弁Bの弁要素はハンドル操作に関連して駆動@
24により往動される一方、後輪のクイロッド65にケ
ーブル50を介して追随する従動軸6により復動される
。ケーブル50は単に機械的変位量を伝達するだけで、
ケーブルに作用する荷重がごく小さく、強度負担が軽減
される。The valve element of differential control valve B is driven in relation to the handle operation.
24, and backward by a driven shaft 6 that follows a Quirod 65 of the rear wheel via a cable 50. The cable 50 merely transmits mechanical displacement;
The load acting on the cable is extremely small, reducing the strength burden.
[発明の実施例]
第1図は本発明に係る後輪操舵機構の概略構成図である
。本発明による後輪操舵機構は前輪舵取機構30の出力
軸2つに関連して回転される駆動軸24を有する差a制
御弁Bと、この差動制御弁Bを経て油圧ポンプ26から
圧油を供給される後輪操舵アクチュエータFと、後輪操
舵アクチュエータFにより駆動されるタイロッド65の
変位量を差動制御弁Bの従動軸6に伝達するケーブル5
0とを備えている。[Embodiments of the Invention] FIG. 1 is a schematic configuration diagram of a rear wheel steering mechanism according to the present invention. The rear wheel steering mechanism according to the present invention includes a differential a control valve B having a drive shaft 24 that is rotated in relation to two output shafts of the front wheel steering mechanism 30, and a hydraulic pump 26 that receives pressure through the differential control valve B. A cable 5 that transmits the displacement amount of the rear wheel steering actuator F supplied with oil and the tie rod 65 driven by the rear wheel steering actuator F to the driven shaft 6 of the differential control valve B.
0.
図示の実施例では、前輪舵角に対する後輪舵角を車速に
関連して制御するための舵角特性徐変機1MAが、軸1
9と駆動軸24の間に備えられ、軸′1つにスプライン
嵌合した制御部材20の突片22と駆動軸24に結合し
た円筒部材21の切欠21aとの相対位置を制御するア
クチュエータDが、i速に関連して油量を調整する油量
調整弁Eにより制御される。また、本発明による後輪操
舵機構には、後輪のタイロッド65を中立位置に保持す
る中立ロック機構Hと、これを制御するアクチュエータ
Gが備えられる。In the illustrated embodiment, the steering angle characteristic gradual variable machine 1MA for controlling the rear wheel steering angle with respect to the front wheel steering angle in relation to the vehicle speed is configured to
9 and the drive shaft 24, and controls the relative position of the protrusion 22 of the control member 20 spline-fitted to one shaft ′ and the notch 21a of the cylindrical member 21 coupled to the drive shaft 24. , is controlled by an oil amount adjustment valve E that adjusts the oil amount in relation to speed i. Further, the rear wheel steering mechanism according to the present invention includes a neutral lock mechanism H that holds the rear wheel tie rod 65 in a neutral position, and an actuator G that controls the neutral lock mechanism H.
ハンドル41を支持する操舵軸37の回転は、公知の前
輪舵取機構30の出力軸2つに伝達され、出力Id12
9と一緒に腕3−1.32が回動される。The rotation of the steering shaft 37 that supports the handle 41 is transmitted to two output shafts of the known front wheel steering mechanism 30, and the output Id12
Arm 3-1.32 is rotated together with 9.
腕32は前後方向のドラッグリンク33と連結される。The arm 32 is connected to a drag link 33 in the front-rear direction.
ドラッグリンク33の後端は、前輪40を支持しかつ上
下方向の支@34により車体に支持された前輪ナックル
38と連結される。前輪ナックル38は左側前輪の同様
の前輪ナックル(図示−せf)とタイロッド39により
運動連結される。The rear end of the drag link 33 is connected to a front wheel knuckle 38 that supports the front wheel 40 and is supported on the vehicle body by a vertical support @34. The front wheel knuckle 38 is movably connected to a similar front wheel knuckle of the left front wheel (FIG. 1-f) by a tie rod 39.
前輪舵取機構30のイ8力1!置を駆動する油圧ポンプ
27は、礪関により駆動される油圧ポンプ26と連、情
される。Front wheel steering mechanism 30 has 8 forces and 1! The hydraulic pump 27 that drives the station is connected to the hydraulic pump 26 that is driven by the pump.
腕31は前輪舵取機構30のハウジングにブラケット1
6(第2図)により支持した軸19の腕36と、リンク
35により運動連結される。軸19にスプライン■合し
た制御部材20の環状溝に制御レバー18の一端部が係
合される。制御レバー18を二股状のフォークとして環
状溝に係合してもよい。The arm 31 is attached to the bracket 1 on the housing of the front wheel steering mechanism 30.
It is connected in motion by a link 35 to an arm 36 of the shaft 19 supported by 6 (FIG. 2). One end of the control lever 18 is engaged in an annular groove in a control member 20 splined to the shaft 19. The control lever 18 may be a bifurcated fork that engages in the annular groove.
制御レバー18は車体の固定部に軸17により回動可能
に支持され、ばね13の力により制御部材20の突片2
2が円筒部材21の切欠21aから軸方向に離れるよう
に回転付勢される〈第2図参照〉。制御レバー18の他
端部はアクチュエータDのピストンロッドと連結される
。第1図には理解を容易にするために、軸17に結合し
た制御レバー18aにビスi〜ンロツドが連結され、ば
ね13はアクチュエータDのシリンダの内部に配設され
る。The control lever 18 is rotatably supported by a shaft 17 on a fixed part of the vehicle body, and the protrusion 2 of the control member 20 is rotated by the force of the spring 13.
2 is rotated and urged to move away from the notch 21a of the cylindrical member 21 in the axial direction (see FIG. 2). The other end of the control lever 18 is connected to the piston rod of the actuator D. In FIG. 1, for ease of understanding, a control lever 18a connected to a shaft 17 is connected to a screw rod, and a spring 13 is disposed inside the cylinder of an actuator D.
カップ形の円筒部材21は周面に開口端側へ拡がりをも
つ楔形の切欠21aを設けられ、この切欠21aに突片
22が当接すると、軸19の回転が円筒部材21へ伝達
され、この円筒部材21と一緒に回転するようにスプラ
インまたはビンなどにより連結された駆動軸24へ伝達
される。駆動軸24は差動制御弁Bの弁要素を駆動する
ねじ部材にリードの大きなねじ溝で螺合される。軸19
の回転に伴う切欠21aと突片22の当接により円筒部
材21の回転が駆動軸24へ伝達されようとする時、駆
動軸24は中立戻しばね114(第3図参照)により中
立位相を維持しようと抵抗するために、切欠21aと突
片22の当接部において楔形の切欠21aの傾斜角に見
合った軸推力が発生する。The cup-shaped cylindrical member 21 is provided with a wedge-shaped notch 21a that widens toward the open end on its circumferential surface, and when the protruding piece 22 comes into contact with this notch 21a, the rotation of the shaft 19 is transmitted to the cylindrical member 21. The signal is transmitted to a drive shaft 24 connected to the cylindrical member 21 by splines, pins, etc. so as to rotate together with the cylindrical member 21 . The drive shaft 24 is screwed into a threaded member that drives the valve element of the differential control valve B through a threaded groove with a large lead. Axis 19
When the rotation of the cylindrical member 21 is about to be transmitted to the drive shaft 24 due to the contact between the notch 21a and the protrusion 22 due to the rotation, the drive shaft 24 maintains the neutral phase by the neutral return spring 114 (see FIG. 3). In order to resist this movement, an axial thrust corresponding to the inclination angle of the wedge-shaped notch 21a is generated at the contact portion between the notch 21a and the protruding piece 22.
円筒部材21と駆動軸24はスプラインまたはビンなど
により軸方向移動を許容されているので、切欠21aと
突片22の当接により軸19の回転が円筒部材21へ伝
達されるのに先立って、まず円筒部材21が駆動軸24
との軸方向移0許容檄(隙間S)だけ移動し、その後に
回転が伝)7される。この時、円筒部材21のごく僅か
な軸方向移動は、円筒部材21の端壁に対設したスイッ
チ23により検出される。このスイッチ23は後jホす
る中立ロック機構Hを制御する。Since the cylindrical member 21 and the drive shaft 24 are allowed to move in the axial direction by a spline or a pin, etc., before the rotation of the shaft 19 is transmitted to the cylindrical member 21 by the contact between the notch 21a and the protrusion 22, First, the cylindrical member 21 is connected to the drive shaft 24.
It moves by the allowable axial displacement (gap S), and then rotation is transmitted)7. At this time, a very slight axial movement of the cylindrical member 21 is detected by a switch 23 provided opposite to the end wall of the cylindrical member 21. This switch 23 controls the neutral locking mechanism H that follows.
アクチュエータDはシリンダの内部に嵌装したピストン
により、油圧が導入される端室と、ばね13を収容する
大気宇とを区画される。アクチユ工−りDの端室へ油圧
ポンプ26から圧油が油量調整弁Eを経て供給される。The actuator D is partitioned into an end chamber into which hydraulic pressure is introduced and an atmospheric chamber in which the spring 13 is housed, by a piston fitted inside the cylinder. Pressure oil is supplied from the hydraulic pump 26 to the end chamber of the actuator D via the oil amount adjustment valve E.
油量調整弁Eは3つのボートを有するハウジング46の
内部に、2つの環状溝を有するスプール48を嵌合して
なり、ばね49を収容する左側の端室と中央のボートと
がアクチュエータDの端室と連通される。中立位置でス
プール48の環状溝に連通するボートの一方が油圧ポン
プ26に、他方が油タンク28に連通される。スプール
48に結合したロンドはハウジング46の外部へ突出し
てアマチュアを構成し、電磁コイル47の電流に対応し
て左方への付勢力を受ける。The oil amount adjusting valve E is constructed by fitting a spool 48 having two annular grooves into a housing 46 having three boats. It communicates with the end chamber. One side of the boat that communicates with the annular groove of the spool 48 in the neutral position is communicated with the hydraulic pump 26, and the other side is communicated with the oil tank 28. The rond coupled to the spool 48 protrudes to the outside of the housing 46 to form an armature, and receives a biasing force to the left in response to the current of the electromagnetic coil 47.
電磁コイル47は車速が低いと電流が大ぎく、車速か高
くなるほど電流が小さくなるように制御される。このた
め、変速機の出力軸の回転を速度計15へ伝達する可撓
軸43に、歯車機構42を介して車速比例電流発生器4
4が結合される。車速比例電流発生器44の両端子は電
流減蓮変換器45に接続され、電源バッテリ51から電
磁コイル47へのN流を制御する。The electromagnetic coil 47 is controlled so that the current is large when the vehicle speed is low, and the current is small as the vehicle speed increases. Therefore, a vehicle speed proportional current generator 4 is connected to a flexible shaft 43 that transmits the rotation of the output shaft of the transmission to the speedometer 15 via a gear mechanism 42.
4 are combined. Both terminals of the vehicle speed proportional current generator 44 are connected to a current reduction converter 45 to control the N current from the power source battery 51 to the electromagnetic coil 47 .
差動制御弁Bは中立位置開放型でもよいが、好ましくは
4ボート・中立位置ブロック型の方向切換弁であり、駆
動軸24の回転に伴って一方の弁要素が軸方向、に移動
し、従動軸6に結合した他方の弁要素との間に相対移動
が生じると、油圧ポンプ26から圧油が管72.75を
経て管76.80の一方へ供給され、他方の管の油が管
79.77を経て油タンク28へ戻される。管76.8
0は特殊な逆止弁53.54を軽で後輪操舵アクチュエ
ータFの両端室89.91と連通される。The differential control valve B may be a neutral position open type, but is preferably a four-boat/neutral position block type directional switching valve, in which one valve element moves in the axial direction as the drive shaft 24 rotates, When a relative movement occurs between the driven shaft 6 and the other valve element, pressure oil is supplied from the hydraulic pump 26 via pipes 72.75 to one of the pipes 76.80, and oil in the other pipe is supplied to the pipe 76.80. It is returned to the oil tank 28 through 79.77. tube 76.8
0 communicates with both end chambers 89,91 of the rear wheel steering actuator F through special check valves 53,54.
第3図は差動制御弁Bの平面断面図である。車体に固定
されるハウジング121の内部へ嵌合した円筒形の弁ハ
ウジング122の内周面中央に、管75に連通ずる環状
溝124が、この両側に環状溝123.125がそれぞ
れ設けられる。また、弁ハウジング122の環状溝12
4の両側に径方向の通路127a、128aが設けられ
る。弁ハウジング122に摺動可能に嵌装される弁要素
としてのスプール126は、外周面に前述の通路127
a、128aに対向する環状溝127,128が設けら
れ、さらに両端側に前述の環状溝123.125に対向
する径方向の通路123a、125aが設けられる。FIG. 3 is a plan sectional view of the differential control valve B. FIG. An annular groove 124 communicating with the pipe 75 is provided at the center of the inner peripheral surface of a cylindrical valve housing 122 fitted inside a housing 121 fixed to the vehicle body, and annular grooves 123 and 125 are provided on both sides of the annular groove 124, respectively. Additionally, the annular groove 12 of the valve housing 122
4 are provided with radial passages 127a, 128a on both sides. A spool 126 as a valve element that is slidably fitted into the valve housing 122 has the aforementioned passage 127 on its outer peripheral surface.
Annular grooves 127, 128 are provided opposite to the annular grooves 123, 128a, and radial passages 123a, 125a are provided at both ends thereof, opposing the aforementioned annular grooves 123, 125.
スプール126の左端面に固定した当て板137とハウ
ジング121の段部に衝合したばね座と、弁ハウジング
122とスプール126の各段部に衝合したばね座との
間に、センタリングばね138が介装される。また、ね
じ部材130にナツト135により固定した座板134
と当て板137に衝合するばね座と、スプール126と
ねじ部材130の各段部に衝合したばね座との間に、オ
ーバストローク吸収用ばね136が介装される。A centering spring 138 is installed between a backing plate 137 fixed to the left end surface of the spool 126, a spring seat that abuts against the stepped portion of the housing 121, and a spring seat that abuts against each step of the valve housing 122 and the spool 126. Intervened. Also, a seat plate 134 fixed to the screw member 130 with a nut 135
An overstroke absorbing spring 136 is interposed between a spring seat that abuts against the backing plate 137 and a spring seat that abuts each step of the spool 126 and the screw member 130.
ハウジング121に回転可能に嵌合した中空の駆動軸2
4に、前述の円筒部材21が嵌合される。Hollow drive shaft 2 rotatably fitted into housing 121
4, the aforementioned cylindrical member 21 is fitted.
駆動軸24の7ランジ24aと円筒部材21のフランジ
21bがビン139により一緒に回転し、カリ円筒部材
21の軸方向に隙間Sだけ移動可能に連結される。円筒
部材21はばね115により駆動軸24に対し軸方向へ
押され、ハウジング121に当接している。この時、切
欠21aの斜面がスイッチ23を押して1回路を開いて
いる。ビン139とハウジング121に固定したビン1
40との間に中立戻しばね(捩りばね)114が介装さ
れ、この中立戻しばね114により駆動軸24の回転位
相が中立位置へ回転付勢される。The seven flange 24a of the drive shaft 24 and the flange 21b of the cylindrical member 21 rotate together by a pin 139, and are connected so as to be movable by a gap S in the axial direction of the pot cylindrical member 21. The cylindrical member 21 is pushed in the axial direction with respect to the drive shaft 24 by the spring 115 and is in contact with the housing 121. At this time, the slope of the notch 21a pushes the switch 23 and opens one circuit. Bin 1 fixed to bin 139 and housing 121
A neutral return spring (torsion spring) 114 is interposed between the drive shaft 24 and the drive shaft 24, and the neutral return spring 114 rotationally biases the rotational phase of the drive shaft 24 to the neutral position.
駆動軸24の内端部に設けたリードの大きなねじ穴13
1に、円筒形のねじ部材130が螺合される。ねじ部材
130の内空部は適当な手段により油タンク28に接続
される一方、径方向の通路133、通路123aを経て
環状溝123に連通し、また通路125aを経て環状溝
125にも連通ずる。ねじ部材130に設けたスプライ
ン穴132に、従動軸6のスプライン軸部が嵌合される
。A large lead screw hole 13 provided at the inner end of the drive shaft 24
1, a cylindrical screw member 130 is screwed together. The inner cavity of the threaded member 130 is connected to the oil tank 28 by suitable means, while communicating with the annular groove 123 via a radial passage 133 and a passage 123a, and also with the annular groove 125 via a passage 125a. . A spline shaft portion of the driven shaft 6 is fitted into a spline hole 132 provided in the screw member 130 .
図示の中立位置では、スプール126の環状溝127の
両側縁は弁ハウジング122の環状溝124の側縁と環
状溝123の側縁とにごく僅かな隙間を存して接し、同
様に環状溝128の両側縁は環状溝124の側縁と環状
溝125の側縁とにごく僅かな隙間を存して接し、各隙
間の量がほぼ同量であるので、圧油は管76と管80の
何れにも均等に油圧を加えることとなり、後輪操舵アク
チュエータFは室89.91の油圧が平衡してピストン
は移動しない。In the illustrated neutral position, both side edges of the annular groove 127 of the spool 126 touch the side edges of the annular groove 124 and the annular groove 123 of the valve housing 122 with a very small gap, and similarly the annular groove 128 The side edges of the annular groove 124 and the annular groove 125 are in contact with the side edges of the annular groove 124 and the annular groove 125 with very small gaps between them, and since the amount of each gap is almost the same, the pressure oil flows through the pipes 76 and 80. Hydraulic pressure is applied equally to both, and the hydraulic pressure in the chambers 89 and 91 of the rear wheel steering actuator F is balanced, and the piston does not move.
なお、各隙間から洩れ出た管75の圧油は管76.80
に均等の圧力を加えながら、通路123a、125aを
経て管79へ入り、管77を経て油タンク28へ戻る。In addition, the pressure oil leaking from the pipe 75 from each gap is contained in the pipe 76.80.
While applying equal pressure to the oil, it enters the pipe 79 through the passages 123a and 125a, and returns to the oil tank 28 through the pipe 77.
駆動軸24が回転されると、その回転力はねじ穴131
に螺合するねじ部材130に伝達され、ねじ部材130
の回転はスプライン穴132を経て従動軸6へ伝達され
る。しかし、駆動軸24の回転量に対応した後輪ナック
ルの動きがないと従動軸6は回転しないので、駆動軸2
4から従動軸6に至る回転伝達経路のねじ穴131にお
いて、ねじのリード角に見合った軸推力がねじ部材13
0に発生する。ねじ部材130に生じた軸推力によりセ
ンタリングばね138の力に抗してねじ部材130と一
体的にスプール126が例えば右方へ移動すると、管7
5の圧油が環状溝124、環状溝127、通路127a
を経て管76へ流れる。When the drive shaft 24 is rotated, the rotational force is applied to the screw hole 131.
The transmission is transmitted to the screw member 130 that is screwed into the screw member 130 .
The rotation is transmitted to the driven shaft 6 through the spline hole 132. However, the driven shaft 6 will not rotate unless the rear wheel knuckle moves in accordance with the amount of rotation of the drive shaft 24.
4 to the driven shaft 6, an axial thrust commensurate with the lead angle of the screw is applied to the screw member 13.
Occurs at 0. When the spool 126 moves, for example, to the right together with the screw member 130 against the force of the centering spring 138 due to the axial thrust generated in the screw member 130, the pipe 7
No. 5 pressure oil is connected to the annular groove 124, the annular groove 127, and the passage 127a.
and into pipe 76.
方、管80の油は通路128a、環状1m128、環状
溝125、通路125a、通路133を経てねじ部材1
30の内空部へ流れ、さらに図示してない通路を経て油
タンク28へ戻される。逆に、スプール126が左方へ
移動すると、管75が管80に連通され、管76がねじ
部材130の内空部へ連通される。On the other hand, the oil in the pipe 80 passes through the passage 128a, the annular 1 m 128, the annular groove 125, the passage 125a, and the passage 133 to the threaded member 1.
30 and is further returned to the oil tank 28 via a passage (not shown). Conversely, when the spool 126 moves to the left, the tube 75 is communicated with the tube 80, and the tube 76 is communicated with the inner cavity of the threaded member 130.
上述のように、管75の圧油が管76と管80の一方に
流れると、後述の後輪操舵アクチュエータEによりタイ
ロッド65が駆動され、これに伴ってケーブル50を介
して従動軸6が回転する。As described above, when the pressure oil in the pipe 75 flows into one of the pipes 76 and 80, the tie rod 65 is driven by the rear wheel steering actuator E, which will be described later, and the driven shaft 6 is accordingly rotated via the cable 50. do.
ねじ部材130が駆動軸24と同方向に回転することに
より両者の相対回転位相差が減少し、スプール126が
中立位置へ戻される。この時、ハンドル41の切り角に
対応した舵角に後輪71が保持される。By rotating the screw member 130 in the same direction as the drive shaft 24, the relative rotational phase difference between the two is reduced, and the spool 126 is returned to the neutral position. At this time, the rear wheels 71 are held at a steering angle corresponding to the turning angle of the steering wheel 41.
第4図に示すように、後輪操舵アクチュエータFはアク
スルハウジング84に取付部材85により支持される。As shown in FIG. 4, the rear wheel steering actuator F is supported by a mounting member 85 on the axle housing 84. As shown in FIG.
タイロッド65の両端が球継手66により補助ロッド6
7と連結され、補助ロッド67は後輪71を支持する後
輪ナックル69と球継手68により連結される。公知の
ように、差動R84aを結合するアクスルハウジング8
4の両端は板ばね83により車枠81に支持される。板
ばね83は前端部の目玉部を車枠81のブラケット82
にビンにより連結される一方、後端部をシャックルと連
結され、このシャックルが車枠81のブラケット86に
ビンにより連結される。アクスルハウジング84に支持
された車軸は等速自在継手により、後輪ナックル69に
支持された後輪71の軸と連結される。後輪ナックル6
9は2分割された上下方向の支軸70(第1図)により
アクスルハウジング84の端部に回動可能に支持される
。Both ends of the tie rod 65 are connected to the auxiliary rod 6 by a ball joint 66.
The auxiliary rod 67 is connected to a rear wheel knuckle 69 that supports the rear wheel 71 by a ball joint 68. As is known, the axle housing 8 that connects the differential R84a
Both ends of 4 are supported by the vehicle frame 81 by leaf springs 83. The leaf spring 83 connects the eye of the front end to the bracket 82 of the vehicle frame 81.
The rear end portion is connected to a shackle by a pin, and the shackle is connected to a bracket 86 of the vehicle frame 81 by a pin. The axle supported by the axle housing 84 is connected to the shaft of the rear wheel 71 supported by the rear wheel knuckle 69 by a constant velocity universal joint. rear wheel knuckle 6
9 is rotatably supported at the end of the axle housing 84 by a vertical support shaft 70 (FIG. 1) that is divided into two parts.
第5図に示すように、後輪操舵アクチュエータFはシリ
ンダ57にピストン56を嵌合して室8991を区画さ
れる。ピストン56に結合したタイロッド65がシリン
ダ57の両@壁92.93に摺動可能に支持される。ビ
ス1〜ン5Gを中立位置(後輪の直進位@)に戻すため
に、タイロッド65に係止した止め輪88に当接するば
ね座87と、ピストン56に当接するばね座90との間
にばね55が介装される。円筒形のばね座87は端部フ
ランジを端壁92に当接される。円筒形のばね座90も
端部フランジをシリンダ57の中間壁98に当接される
。管76と室89とを結ぶ端壁92の通路に逆止弁53
が、管80とv91に連なる管80bとを結ぶ中間壁9
8に逆止弁54がそれぞれ配設される。逆止弁53,5
4は同じ構成のものである。As shown in FIG. 5, the rear wheel steering actuator F has a cylinder 57 fitted with a piston 56 to define a chamber 8991. A tie rod 65 connected to the piston 56 is slidably supported on both walls 92,93 of the cylinder 57. In order to return the screws 1 to 5G to the neutral position (straight forward position of the rear wheel), a spring seat 87 that comes into contact with a retaining ring 88 that is engaged with the tie rod 65 and a spring seat 90 that comes into contact with the piston 56 are installed. A spring 55 is interposed. A cylindrical spring seat 87 has an end flange abutted against an end wall 92 . A cylindrical spring seat 90 also bears with its end flange against the intermediate wall 98 of the cylinder 57 . A check valve 53 is provided in the passageway of the end wall 92 connecting the pipe 76 and the chamber 89.
is the intermediate wall 9 connecting the pipe 80 and the pipe 80b connected to v91.
A check valve 54 is provided at 8, respectively. Check valve 53,5
4 has the same configuration.
第6図に示すように、端壁93はタイロッド65を中立
位置にロックする中立ロック機構Hのハウジング94と
一体に構成される。ハウジング94の内部において、タ
イロッド65に円錐形の穴60または環状溝を備えた受
入部材58が結合され、かつハウジング94に沿って摺
動可能に案内される。一方、ハウジング94にスイッチ
62を備えたアクチュエータGが固定される。アクチュ
エータGはシリンダ63にピストン64を嵌合して下側
に室96を、上側にばね61を収容する大気室を区画さ
れる。ピストン64に結合したロック部材59が、ハウ
ジング94の壁部を貫通して受入部材58の円錐穴6o
に係合可能とされる。As shown in FIG. 6, the end wall 93 is constructed integrally with a housing 94 of a neutral locking mechanism H that locks the tie rod 65 in the neutral position. Inside the housing 94 , a receiving member 58 with a conical hole 60 or an annular groove is connected to the tie rod 65 and is slidably guided along the housing 94 . On the other hand, an actuator G including a switch 62 is fixed to the housing 94. The actuator G has a piston 64 fitted into a cylinder 63 to define a chamber 96 on the lower side and an atmospheric chamber accommodating the spring 61 on the upper side. A locking member 59 coupled to the piston 64 passes through the wall of the housing 94 and is inserted into the conical hole 6o of the receiving member 58.
can be engaged with.
室96に管74から圧油を供給すると、ロック部材5つ
が押し上げられ、受入部材58との係合が解除される。When pressure oil is supplied to the chamber 96 from the pipe 74, the five locking members are pushed up and the engagement with the receiving member 58 is released.
ロック解除動作を検出するスイッチ62は、可動接片6
2aをピストン64に当接され、ピストン64が図示の
ロック位置から解除方向に移動し始めると、すぐ回路を
閉じる。A switch 62 that detects a lock release operation is a movable contact piece 6
2a is brought into contact with the piston 64, and as soon as the piston 64 begins to move from the illustrated locking position in the release direction, the circuit is immediately closed.
第7図は逆止弁53の構成を示す断面図である。FIG. 7 is a sectional view showing the structure of the check valve 53.
端壁92に管76に連通する通路と交差して管80aに
連通するシリンダ102と、室89に連通する弁孔10
6とが形成される。シリンダ102に嵌合したピストン
104は管80aと管76との間を遮断し、シリンダ1
02に油圧が作用すると、弁孔106に嵌合したステム
107に当接するロッド105により弁体108が端壁
92から押し離される。弁体108を支持するステム1
07は、管76と至89を連通する軸方向溝を備えてい
る。弁体108から室89△、突出するステム111に
ばね座110が摺動可能に嵌合され、かつ止め輪103
aによりステム111から扱けないように支持される。A cylinder 102 that intersects the passage communicating with the pipe 76 and communicates with the pipe 80a is provided in the end wall 92, and a valve hole 10 that communicates with the chamber 89.
6 is formed. The piston 104 fitted into the cylinder 102 blocks the pipe 80a and the pipe 76, and the piston 104 fits into the cylinder 102.
When hydraulic pressure is applied to valve 02, valve element 108 is pushed away from end wall 92 by rod 105 that abuts stem 107 fitted in valve hole 106. Stem 1 supporting valve body 108
07 is provided with an axial groove that communicates between the tube 76 and the to 89. A spring seat 110 is slidably fitted to a stem 111 protruding from the chamber 89Δ from the valve body 108, and the retaining ring 103
a so that it cannot be handled from the stem 111.
弁体108とばね座110との間にばね112が介装さ
れる。このばね112により弁体108が端壁92へ押
し付けられる。A spring 112 is interposed between the valve body 108 and the spring seat 110. This spring 112 presses the valve body 108 against the end wall 92 .
ばね座87が右方へ移動すると、ばね座110と端壁9
2との間に介装したばね109により、弁体108は端
壁92から離れる。When the spring seat 87 moves to the right, the spring seat 110 and the end wall 9
2, the valve body 108 is separated from the end wall 92.
第1図に示すように、中立ロック機構Hの受入部材58
にケーブル50の一端が連結され、他端は第2図に示す
クラッチ板つと一体のレバー9aと連結される。ケーブ
ル50は一端を車体側に、他端を後輪操舵アクチュエー
タFのハウジング57にそれぞれ固定したアウタチュー
ブく図示せず)に挿通され、受入部材58を支持するタ
イロッド65の変位闇をレバー9aに伝達する。第2図
に示すように、車体に軸4により回動可能に支持したベ
ルクランク10とレバー9aとの間にばね5が掛は渡さ
れ、このばね5によりベルクランク10がストッパ11
に当接されるとともに、レバー9aが回動されてケーブ
ル5oが弛みのないように緊張される。As shown in FIG. 1, the receiving member 58 of the neutral locking mechanism H
One end of the cable 50 is connected to the lever 9a, and the other end is connected to a lever 9a integrated with the clutch plate shown in FIG. The cable 50 is inserted into an outer tube (not shown) that has one end fixed to the vehicle body side and the other end fixed to the housing 57 of the rear wheel steering actuator F, and is connected to the lever 9a by the displacement of the tie rod 65 that supports the receiving member 58. introduce. As shown in FIG. 2, a spring 5 is applied between a lever 9a and a bell crank 10 rotatably supported on the vehicle body by a shaft 4.
At the same time, the lever 9a is rotated and the cable 5o is tightened so that it does not become loose.
万一、ケーブル50が折損すると、ベルクランク10と
車体との間に掛は渡した弱いばね12により、ベルクラ
ンク10が軸4を中心として回動され、リンクロッド3
により後述する油圧回路の常閉型の開閉弁2(第1図)
が開かれる。In the unlikely event that the cable 50 is broken, the bell crank 10 is rotated about the shaft 4 by the weak spring 12 that is passed between the bell crank 10 and the vehicle body, and the link rod 3
A normally closed on-off valve 2 (Fig. 1) of a hydraulic circuit, which will be described later.
will be held.
レバー9aはクラッチ板9と一体をなし、従動軸6に遊
回転回能に支持される。電磁クラッチCの電磁コイル8
が励磁されると、クラッチ板9が従動軸6に結合した円
板7に摩擦係合され、レバー9aの回動が従動軸6へ伝
達される。The lever 9a is integral with the clutch plate 9 and supported by the driven shaft 6 for free rotation. Electromagnetic coil 8 of electromagnetic clutch C
When the clutch plate 9 is excited, the clutch plate 9 is frictionally engaged with the disk 7 connected to the driven shaft 6, and the rotation of the lever 9a is transmitted to the driven shaft 6.
第1図に示すように、中立ロック機構Hを解除するアク
チュエータGを駆動するために、油圧ポンプ26の吐出
口は管72,73、電磁切換弁52、管74を経てアク
チュエータGの室96に連通される。中立ロック機構H
をロックする時、室96は管74、電磁切換弁52、管
78.77を経て油タンク28と連通される。電磁切換
弁52は舵角特性徐変機構Aの円筒部材21の作動を検
出するスイッチ23と運動して切り換えられる。As shown in FIG. 1, in order to drive the actuator G that releases the neutral lock mechanism H, the discharge port of the hydraulic pump 26 is connected to the chamber 96 of the actuator G via pipes 72, 73, the electromagnetic switching valve 52, and the pipe 74. communicated. Neutral lock mechanism H
When locked, the chamber 96 is communicated with the oil tank 28 via the pipe 74, the electromagnetic switching valve 52, and the pipes 78 and 77. The electromagnetic switching valve 52 is switched by movement with the switch 23 that detects the operation of the cylindrical member 21 of the steering angle characteristic gradual change mechanism A.
車速が所定値(例えば20km/h)を超えた時、後輪
操舵機構の油圧回路を開放して中立位置へ戻すために、
m源バッテリ51に対し、管72と管77の間に挿入接
続した常閉型の電磁開閉弁25と、速度計15の針が所
定値を超えた時閉じるスイッチ14とが直列に接続され
る。When the vehicle speed exceeds a predetermined value (for example, 20 km/h), the hydraulic circuit of the rear wheel steering mechanism is opened to return it to the neutral position.
A normally closed electromagnetic on-off valve 25 inserted and connected between pipes 72 and 77 and a switch 14 that closes when the needle of the speedometer 15 exceeds a predetermined value are connected in series to the m-source battery 51. .
次に、本発明による後輪操舵機構の作動について説明す
る。例えばハンドル41を右へ切ると、前輪舵取機構3
0の出力軸29が回動され、腕32によりドラッグリン
ク33が前方へ引かれ、前輪ナックル38が支軸34を
中心として時計方向へ回動され、前輪40が右へ偏向さ
れる。同時に、出力軸29の回動が軸19へ伝達され、
この時車速が所定値以下にあり、前輪舵角が所定値を超
えると、突片22が円筒部材21の切欠21aに当接し
、駆動軸24が矢印方向へ回転される。同時に、スイッ
チ23が閉じ、電磁切換弁52が管73と管74を連通
する状態に切り換わる。Next, the operation of the rear wheel steering mechanism according to the present invention will be explained. For example, when the steering wheel 41 is turned to the right, the front wheel steering mechanism 3
0 output shaft 29 is rotated, the drag link 33 is pulled forward by the arm 32, the front wheel knuckle 38 is rotated clockwise about the support shaft 34, and the front wheel 40 is deflected to the right. At the same time, the rotation of the output shaft 29 is transmitted to the shaft 19,
At this time, when the vehicle speed is below a predetermined value and the front wheel steering angle exceeds a predetermined value, the protrusion 22 comes into contact with the notch 21a of the cylindrical member 21, and the drive shaft 24 is rotated in the direction of the arrow. At the same time, the switch 23 is closed, and the electromagnetic switching valve 52 is switched to a state where the pipes 73 and 74 are communicated with each other.
電磁切換弁52が切り換わると、油圧ポンプ26の圧油
が管72,73.74を経てアクチュエータGの室96
へ供給され、ピストン64が上方l\移動し、ロック部
材5つがタイロッド65の受入部材58から外れる。こ
の時、スイッチ62が閉じ、電源バッテリ51から電磁
クラッチC、スイッチ62へ通電される。When the electromagnetic switching valve 52 is switched, the pressure oil from the hydraulic pump 26 flows through the pipes 72, 73, and 74 to the chamber 96 of the actuator G.
is supplied, the piston 64 moves upward l\, and the five locking members are disengaged from the receiving member 58 of the tie rod 65. At this time, the switch 62 is closed, and power is supplied from the power source battery 51 to the electromagnetic clutch C and the switch 62.
方、差動ill I弁Bにおいて、弁要素の軸移動が生
じ、管75が管76に、管79が管80にそれぞれ連通
する。後輪操舵アクチュエータEの字89に圧油が供給
され、室91の油は油タンク281\戻される。タイロ
ッド65が右方へ移動し、後輪ナックル69が支軸70
を中心として反時計方向に回動し、後輪71が左(前輪
と反対方向)へ偏向される。こうして、車両の低速走行
での小回り性が向上される。On the other hand, in the differential ill I valve B, an axial movement of the valve element occurs, and the pipe 75 communicates with the pipe 76 and the pipe 79 communicates with the pipe 80, respectively. Pressure oil is supplied to the rear wheel steering actuator E-shaped 89, and the oil in the chamber 91 is returned to the oil tank 281\. The tie rod 65 moves to the right, and the rear wheel knuckle 69 moves to the support shaft 70.
The rear wheel 71 is rotated counterclockwise around , and the rear wheel 71 is deflected to the left (in the opposite direction to the front wheel). In this way, the turning ability of the vehicle when traveling at low speeds is improved.
タイロッド65の右移動はケーブル50を経てクラッチ
板つと一体のレバー9aに伝達され、従動軸6を回転さ
せる。作動制御弁Bの弁要素が中立位置に至ったところ
で、管75が管76から遮断され、管80が管7つから
遮断されるので、後輪操舵アクチュエ〜りFはその位1
に停止する。The rightward movement of the tie rod 65 is transmitted via the cable 50 to the lever 9a integrated with the clutch plate, thereby rotating the driven shaft 6. When the valve element of the actuation control valve B reaches the neutral position, the pipe 75 is cut off from the pipe 76 and the pipe 80 is cut off from the pipes 7, so that the rear wheel steering actuator
Stop at.
上述のように、ハンドル41の切り角に対応して後輪操
舵アクチュエータFが作動し、後輪71が操舵される。As described above, the rear wheel steering actuator F operates in accordance with the turning angle of the steering wheel 41, and the rear wheels 71 are steered.
前輪40の舵角に対する後輪71の舵角は第8図に線a
1で表される。ここで、車速が増加すると、舵角特性徐
変機構への作用によりハンドル41がその切り角に保持
されている場合でも、第8図の線a2の方へ乗り移り、
後輪舵角が小さくなる。つまり、突片22を支持する制
御部材20が軸19に対して右方へ移動し、突片22と
切欠21aとの間に隙間が生じるので、中立戻しばね〈
図示せず〉の作用により円筒部材21が逆方向に回動し
、差動制御弁Bの弁要素に軸移動が生じ、管75が管8
0に、管79が管76にそれぞれ連通され、後輪操舵ア
クチュエータFによりタイロッド65が左方へ移動し、
後輪71の舵角が小さくなる。The steering angle of the rear wheels 71 relative to the steering angle of the front wheels 40 is shown by line a in FIG.
It is represented by 1. Here, when the vehicle speed increases, even if the steering wheel 41 is held at the steering angle due to the action on the steering angle characteristic gradual change mechanism, it shifts toward the line a2 in FIG.
The rear wheel steering angle becomes smaller. In other words, the control member 20 supporting the protruding piece 22 moves to the right with respect to the shaft 19, and a gap is created between the protruding piece 22 and the notch 21a, so that the neutral return spring
The cylindrical member 21 rotates in the opposite direction due to the action of
0, the pipes 79 are communicated with the pipes 76, and the tie rod 65 is moved to the left by the rear wheel steering actuator F.
The steering angle of the rear wheels 71 becomes smaller.
こうして、低速では前輪舵角に対する後輪舵角の割合が
大きいが、高速になると自動的に小さくなり、車両の安
全性が確保される。車速が所定値以上では着初制御弁B
は作動せず、後輪操舵アクチュエータFは中立位置にあ
り、中立ロック機構Hが働き、後輪71は直進位置に保
持される。In this way, the ratio of the rear wheel steering angle to the front wheel steering angle is large at low speeds, but automatically decreases at high speeds, ensuring vehicle safety. When the vehicle speed exceeds a predetermined value, the arrival control valve B
is not activated, the rear wheel steering actuator F is in the neutral position, the neutral locking mechanism H is activated, and the rear wheels 71 are held in the straight-ahead position.
第5.7図に示すように、接輪操舵アクチュエータFが
中立位置にある時、逆止弁53.54は閉じていて管7
6と789との間を′a断し、管80とW91との間を
遮断する。タイロッド65が右方へ駆動される時、管7
6の油圧は逆止弁53の弁体108に圧力を及ぼし、ば
ね112の力に抗して逆止弁53を押し開く。同時に、
管76の圧油は管76aを経て逆止弁54の端部からピ
ストン104に圧力を及ぼし、弁体108をばね112
の力に抗して押し開く。この時ばね座110はばね55
の力を受けるばね座90により、中間壁98に支持した
ロッド90aを介して押えられる。ピストン56が左方
へ駆動される場合も同様に逆止弁53,54が管80a
、80の油圧により押し開かれる。As shown in Figure 5.7, when the contact wheel steering actuator F is in the neutral position, the check valves 53, 54 are closed and the pipe 7
6 and 789, and the pipe 80 and W91 are cut off. When the tie rod 65 is driven to the right, the tube 7
6 exerts pressure on the valve body 108 of the check valve 53 and pushes the check valve 53 open against the force of the spring 112. at the same time,
The pressure oil in the pipe 76 exerts pressure on the piston 104 from the end of the check valve 54 through the pipe 76a, causing the valve body 108 to be compressed by the spring 112.
Push open against the force of. At this time, the spring seat 110 is the spring 55
It is held down by the spring seat 90 which receives the force of the rod 90a supported on the intermediate wall 98. Similarly, when the piston 56 is driven to the left, the check valves 53 and 54 are connected to the pipe 80a.
, 80 hydraulic pressure.
後輪操舵中に油圧回路の油圧が失陥した(例えば管76
の亀裂)場合は、ピストン56ばばね55の力によりゆ
っくりと中立位置へ戻される。例えばピストン56が左
方へ戻る時、ばね座87は端壁92と逆止弁53のばね
座110から離れているので、ばね109の力により弁
体108が端壁92から離れ、室89と管76を連通さ
せ、ピストン56の中立位置への戻りを妨げない。逆止
弁54は閉じたままであるから、後輪71に路面からの
外乱入力が加わり、後輪舵角が増大する方向(中立位置
から離れる方向)へタイロッド65が移動しようとして
も、室91が閉鎖状態になっているので、タイロッド6
5の移動が阻止され、後輪が勝手に操舵されることはな
く、これにより安全が確保される。Hydraulic pressure in the hydraulic circuit fails while steering the rear wheels (e.g. pipe 76
crack), the piston 56 is slowly returned to the neutral position by the force of the spring 55. For example, when the piston 56 returns to the left, the spring seat 87 is separated from the end wall 92 and the spring seat 110 of the check valve 53, so the force of the spring 109 causes the valve body 108 to separate from the end wall 92, and the chamber 89 The tube 76 is brought into communication and the return of the piston 56 to the neutral position is not obstructed. Since the check valve 54 remains closed, even if disturbance input from the road surface is applied to the rear wheels 71 and the tie rod 65 attempts to move in a direction that increases the rear wheel steering angle (away from the neutral position), the chamber 91 will not close. Since it is in the closed state, tie rod 6
5 is prevented from moving, and the rear wheels are not steered without permission, thereby ensuring safety.
上述の実施例において、中立ロック機構日は後輪操舵ア
クチュエータFの内部へ配設することができる。また、
舵角特性徐変機構Aを廃止して軸19を駆動軸24に直
接連結すれば、第8図に破線すで示す舵角特性が得られ
る。この場合、中立ロックIfl*Hと1!磁クラツチ
Cは設けないで、ケーブル50の端部を従動軸6のレバ
ー9aに連結することが好ましい。In the embodiment described above, the neutral locking mechanism can be arranged inside the rear wheel steering actuator F. Also,
If the steering angle characteristic gradual change mechanism A is abolished and the shaft 19 is directly connected to the drive shaft 24, the steering angle characteristic already shown by the broken line in FIG. 8 can be obtained. In this case, neutral lock Ifl*H and 1! It is preferable to connect the end of the cable 50 to the lever 9a of the driven shaft 6 without providing the magnetic clutch C.
また、後輪操舵アクチュエータFにおいて、逆出弁53
.54がタイロッド65と平行に配設され、ばね座87
.90により作動されるように構成したが、逆止弁53
.54をタイロッド65に対し垂直に配設し、タイロッ
ドに形成したカムにより作動させることができる。In addition, in the rear wheel steering actuator F, the backflow valve 53
.. 54 is arranged parallel to the tie rod 65, and the spring seat 87
.. The check valve 53 is configured to be operated by the check valve 90.
.. 54 is disposed perpendicularly to the tie rod 65 and can be actuated by a cam formed on the tie rod.
上述の差D till m弁では、駆O@と従動軸の回
転位相差を、ねじとスプラインの作用でねし部材の移動
量に変換し、これを通常のスプールに伝達することによ
り油量を静1tlDl、ているが、駆動軸と従動軸の回
転位相差により直接油量を制御する回転スプール型の差
動1i11yA弁を用いてもよい。In the above-mentioned differential D till m valve, the rotational phase difference between the driving shaft and the driven shaft is converted into the amount of movement of the screw member by the action of the screw and spline, and this is transmitted to the normal spool to control the oil amount. However, a rotary spool type differential 1i11yA valve that directly controls the oil amount based on the rotational phase difference between the drive shaft and the driven shaft may be used.
[発明の効果]
本発明は上)!のように、油圧源を着初制御弁を経てタ
イロッドを駆動する後輪操舵アクチュエータに接続し、
車速に関連して回転量が変化する駆動軸により差動制m
+井の弁要素を従動させ、タイロッドにケーブルを介し
て運動連結した従動軸により弁要素を復動させるように
したから、前輪の舵角に応じて差aυ制御弁の弁要素が
駆動され、後輪操舵アクチュエータへの油圧回路が生じ
、後輪が前輪と反対方向に偏向されるので、低速走行で
の小回り性が向上される。[Effect of the invention] The present invention is above)! Connect the hydraulic power source to the rear wheel steering actuator that drives the tie rod via the first control valve, as shown in the figure below.
Differential braking using a drive shaft whose rotation amount changes in relation to vehicle speed
Since the valve element of the +well is driven and the driven shaft is movably connected to the tie rod via a cable, the valve element of the differential aυ control valve is driven in accordance with the steering angle of the front wheels. A hydraulic circuit is generated to the rear wheel steering actuator, and the rear wheels are deflected in the opposite direction to the front wheels, thereby improving turning ability at low speeds.
後輪のタイロッドの変位はケーブルを通じて弁要素を復
eさせる従動軸に回転として伝達され、弁要素が中立位
置へ戻ると、油圧回路がa!Fiまたは中立状態とされ
、その偏向位置に後輪が保持される。The displacement of the tie rod of the rear wheel is transmitted as rotation through the cable to the driven shaft that returns the valve element, and when the valve element returns to the neutral position, the hydraulic circuit a! Fi or neutral state is established, and the rear wheels are held at that deflection position.
弁要素を復動させるものは、後輪のタイロッドの変位を
伝達するケーブルであるから、構成か定、常に簡単であ
り、また弁要素の動作抵抗は極めて小さいから、ケーブ
ルが伸びるなどの強度上に問題はなく、円滑で安定した
後輪舵角制御が達せられる。What makes the valve element move back is a cable that transmits the displacement of the tie rod of the rear wheel, so the structure is fixed and always simple, and the operating resistance of the valve element is extremely small, so there is no need for strength issues such as stretching of the cable. There are no problems with this, and smooth and stable rear wheel steering angle control can be achieved.
第1図は本発明に係る後輪操舵機構の概略構成図、第2
図はハンドル操作と車速に関連して後輪操舵アクチュエ
ータへの油量を制御する制御部の斜視図、第3図は差動
制御弁の平面断面図、第4図は後輪操舵アクチュエータ
が配設される後輪懸架機構の平面図、第5図は後輪操舵
アクチュエータの平面断面図、第6図は後輪のタイロッ
ドの中立ロック機構を示す平面断面図、第7図は後輪操
舵アクチュエータに備えられる逆止弁の平面断面図、第
8図は後輪操舵機構の舵角特性線図である。
A:舵角特性徐変機構 B:差動制御弁 C:電磁クラ
ッチ Dニアクチュエータ E;油量調整弁 F:後輪
操舵アクチュエータ G:アクチュエータ H:中立ロ
ック機構 9:クラッチ板2つ二円筒部材 ・22:突
片 26:油圧ポンプ30:前輪舵取機構 40:前輪
41;ハンドル 45:電流減譚変換器 50:ケー
ブル 51:電源バッテリ 52:電磁切換弁 53,
54:逆止弁 59:ロック部材 65:タイロッド
71:後輪
特許出願人 いすず自動車株式会社FIG. 1 is a schematic configuration diagram of a rear wheel steering mechanism according to the present invention, and FIG.
The figure is a perspective view of the control unit that controls the amount of oil to the rear wheel steering actuator in relation to steering wheel operation and vehicle speed, Figure 3 is a plan cross-sectional view of the differential control valve, and Figure 4 is a diagram showing the arrangement of the rear wheel steering actuator. 5 is a plan view of the rear wheel steering actuator, FIG. 6 is a plan view of the neutral locking mechanism for the rear wheel tie rod, and FIG. 7 is the rear wheel steering actuator. FIG. 8 is a cross-sectional plan view of a check valve provided in the vehicle, and FIG. 8 is a steering angle characteristic diagram of the rear wheel steering mechanism. A: Steering angle characteristic gradual change mechanism B: Differential control valve C: Electromagnetic clutch D near actuator E: Oil amount adjustment valve F: Rear wheel steering actuator G: Actuator H: Neutral lock mechanism 9: Two clutch plates and two cylindrical members・22: Protruding piece 26: Hydraulic pump 30: Front wheel steering mechanism 40: Front wheel 41; Handle 45: Current reduction converter 50: Cable 51: Power battery 52: Solenoid switching valve 53,
54: Check valve 59: Lock member 65: Tie rod
71: Rear wheel patent applicant Isuzu Motors Co., Ltd.
Claims (1)
輪操舵アクチュエータに接続し、ハンドルの切り角に関
連して回転する駆動軸により差動制御弁の弁要素を往動
し、後輪ナックルにケーブルを介して運動連結する従動
軸により弁要素を復動させることを特徴とする後輪操舵
機構。The hydraulic power source is connected to the rear wheel steering actuator that drives the rear wheel knuckles through the differential control valve, and the valve element of the differential control valve is moved forward by the drive shaft that rotates in relation to the turning angle of the steering wheel. A rear wheel steering mechanism characterized in that a valve element is moved back by a driven shaft that is movably connected to a knuckle via a cable.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP63216176A JP2778045B2 (en) | 1988-08-30 | 1988-08-30 | Rear wheel steering mechanism |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP63216176A JP2778045B2 (en) | 1988-08-30 | 1988-08-30 | Rear wheel steering mechanism |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0263973A true JPH0263973A (en) | 1990-03-05 |
JP2778045B2 JP2778045B2 (en) | 1998-07-23 |
Family
ID=16684478
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP63216176A Expired - Lifetime JP2778045B2 (en) | 1988-08-30 | 1988-08-30 | Rear wheel steering mechanism |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2778045B2 (en) |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61134956A (en) * | 1984-12-06 | 1986-06-23 | Matsushita Electric Ind Co Ltd | Driving device of magnetic tape |
-
1988
- 1988-08-30 JP JP63216176A patent/JP2778045B2/en not_active Expired - Lifetime
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61134956A (en) * | 1984-12-06 | 1986-06-23 | Matsushita Electric Ind Co Ltd | Driving device of magnetic tape |
Also Published As
Publication number | Publication date |
---|---|
JP2778045B2 (en) | 1998-07-23 |
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