JPH02231272A - Rear wheel steering device for vehicle - Google Patents

Abstract

PURPOSE:To obtain the device which possesses the superior durability with the simple constitution by steering rear wheels by shifting an output shaft in the car width direction through a pair of contact members which externally contact a cam member when said cam member is turned according to the steering angle of a front wheel and improving the bearing-supporting method for the supporting shaft by the cam member. CONSTITUTION:When a steering wheel is operated, an intermediate shaft 23 for connecting a front wheel steering device and a rear wheel steering device 20 is turned according to the steering angle of a front wheel, and further a cam member 38 is turned through a worm gear mechanism 70. At the same time, if the front wheel is steered over a prescribed steering angle in the leftward turning direction, rollers 37R and 37L roll on the second and third cam surfaces 62 and 63, and an output shaft 26 shifts leftward, and the right and left rear wheels are steered in the left turning direction through a pair of tie rods 28. In this case, the cam member 38 is supported onto the upper and lower housings 30 and 31 through a supporting shaft 39 and radial bearings 40 and 41, and the movement is regulated by thrust bearings 43 and 44 so that the shift in the axial direction for the housing 30 is prevented.

Description

【発明の詳細な説明】 〔産業上の利用分野］ 本発明は車両の後輪操舵装置、例えば前輪の転舵角が大
きいときに前輪に対して後輪を逆位相で転舵させる後輪
操舵装置に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a rear wheel steering device for a vehicle, for example, a rear wheel steering device that steers the rear wheels in an opposite phase to the front wheels when the steering angle of the front wheels is large. Regarding equipment.

〔従来技術〕[Prior art]

従来、車両の４輪操舵装置に含まれる後輪操舵装置とし
て、低車速時には前輪に対して後輪を逆位相に操舵しま
た高車速時には前輪に対して後輪を同位相に操舵する車
速感心型のものと、前輪の転舵角が小さいときには前輪
に対して後輪を同位相に操舵しまた前輪の転舵角が大き
いときには前輪に対して後輪を逆位相に操舵する舵角感
応型のもの（例えば、特開昭６１−１８５７２号公報参
照）とが知られている。Conventionally, as a rear wheel steering device included in a vehicle's four-wheel steering device, a vehicle speed sensor is used that steers the rear wheels in the opposite phase to the front wheels at low vehicle speeds, and steers the rear wheels in the same phase as the front wheels at high vehicle speeds. type, and a steering angle sensitive type that steers the rear wheels in the same phase as the front wheels when the steering angle of the front wheels is small, and steers the rear wheels in the opposite phase to the front wheels when the steering angle of the front wheels is large. (For example, see Japanese Patent Laid-Open No. 18572/1983).

上記舵角感応型の後輪操舵装置の構造を簡単化するため
、カム機構を採用したものが特開昭６３−９７４６８号
公報に記載されている。In order to simplify the structure of the above-mentioned steering angle sensitive rear wheel steering device, a device employing a cam mechanism is described in Japanese Patent Laid-Open No. 63-97468.

この後輪操舵装置においては、ステアリングハンドルに
連動する入力軸が左右の後輪間まで延設され、この入力
軸にカム板が固着され、カム板の左右両側にはカム従動
部としての球状ブ・ンシュを有する１対の従動節レバー
が配設され、各従動節レバーの前端部が鉛直の框支軸回
りに回動自在に車体に枢着され、１対の従動節レバーの
後端部同士をターンバックルで連結することにより１対
の球状プッシュがカム板の外周面両側に当接状に保持さ
れ、各従動節レバーの途中部はタイロツドを介して後輪
のナックルアームに連結されている。In this rear wheel steering device, an input shaft linked to the steering handle extends between the left and right rear wheels, a cam plate is fixed to this input shaft, and spherical cams are mounted on both left and right sides of the cam plate as cam driven parts.・A pair of driven joint levers having a hinge are arranged, the front end of each driven joint lever is pivotally attached to the vehicle body so as to be rotatable around a vertical frame support shaft, and the rear end of the pair of driven joint levers is By connecting them with a turnbuckle, a pair of spherical pushers are held in contact with both sides of the outer peripheral surface of the cam plate, and the middle part of each driven joint lever is connected to the knuckle arm of the rear wheel via a tie rod. There is.

上記カム板は曲面状の外周面を有する略三角形状である
。The cam plate has a substantially triangular shape with a curved outer peripheral surface.

上記後輪操舵装置において、ステアリングハンドルを操
舵すると入力軸を介してカム板が回転し、カム板により
１対の球状プッシュが左方又は右方へ移動し、１対の従
動節レバーと１対のタイロッドを介して後輪が左旋回方
向又は右旋回方向へ転舵される。In the above rear wheel steering device, when the steering wheel is steered, the cam plate rotates via the input shaft, and the cam plate moves a pair of spherical pushers to the left or right, and a pair of driven knob levers and a pair of spherical pushers move to the left or right. The rear wheels are steered to the left or right turning direction via the tie rods.

自動車の走行時、特にコーナリング時など後輪からタイ
ロッドを介して後輪操舵装置に数１００廟もの外力が作
用する。When a car is running, especially when cornering, hundreds of external forces act on the rear wheel steering device from the rear wheels via the tie rods.

〔発明が解決しようとする課題〕[Problem to be solved by the invention]

上記説明した後輪操舵装置においては、前後方向に長い
１対の従動節レバーを設けるので、装置が大型化し、後
輪駆動系や後輪サスペンション装置との関係で配置上の
困難が生じる。In the above-described rear wheel steering device, since a pair of driven joint levers that are long in the front and rear direction are provided, the device becomes large in size, and there are difficulties in arrangement in relation to the rear wheel drive system and the rear wheel suspension device.

特に、左右１対の球状プッシュと入力軸とは鉛直方向に
シフトしていることから、自動車のコーナリング時に一
方のタイロッドから従動節レバー及び球状プッシュを介
してカム板の一例部に作用する大きな外力によって、カ
ム板に大きな回転モーメントが作用する。そのため、ス
テアリングハンドルの操作力が非常に重くなるという致
命的な問題がある。In particular, since the pair of left and right spherical pushers and the input shaft are shifted in the vertical direction, a large external force is applied from one tie rod to a portion of the cam plate through the driven joint lever and the spherical pusher when the car is cornering. As a result, a large rotational moment acts on the cam plate. Therefore, there is a fatal problem in that the operating force of the steering wheel becomes extremely heavy.

そこで、本出願人は上記従動節レバーやターンバックル
を省略して構造を簡単化するため、左右１対のタイロッ
ドを介して左右の後輪を連結する１本の出力軸を設け、
出力軸に設けた左右１対のローラ部材を鉛直方向向きの
カム部材の左右両側部に当接させ、カム部材に固着され
カム部材を支持する支軸の両端部をハウジングに支持す
る構成とし、上記出力軸の大部分とローラ部材とカム部
材とカム部材に前輪捏舵系からの入力を伝達するギャ機
構等をハウジング内に収容してなる後輪操舵装置を開発
し実用化した。Therefore, in order to simplify the structure by omitting the driven joint lever and turnbuckle, the present applicant provided a single output shaft that connects the left and right rear wheels via a pair of left and right tie rods.
A pair of left and right roller members provided on the output shaft are brought into contact with both left and right sides of a vertically oriented cam member, and both ends of a support shaft that is fixed to the cam member and supports the cam member are supported by the housing, We have developed and put into practical use a rear wheel steering device in which most of the output shaft, a roller member, a cam member, and a gear mechanism for transmitting input from the front wheel steering system to the cam member are accommodated in a housing.

ところで、後輪からの外力がタイロッドを介して出力軸
に伝達され、出力軸からハウジングに加わる外力によっ
てハウジングに曲げモーメントが作用し、支軸がハウジ
ングに対して軸方向に相対移動すると、上記ギヤ機構の
ギヤの噛み合いが外れたり或いはローラ部材がカム部材
に良好に当接しなくなったり、支軸の端面や環状端面が
ハウジングに摺接して大きな摺動抵抗が作用したり、支
軸やハウジングが摩耗したりするという問題がある。By the way, when the external force from the rear wheel is transmitted to the output shaft via the tie rod, and the external force applied from the output shaft to the housing causes a bending moment to act on the housing, and the support shaft moves relative to the housing in the axial direction, the above gear The gears of the mechanism may become disengaged, the roller member may not contact the cam member properly, the end face or annular end face of the support shaft may slide against the housing, creating large sliding resistance, or the support shaft or housing may become worn out. There is a problem of doing something like that.

本発明の目的は、節単な構成で且つ小型であって信顛性
・耐久性に優れた舵角感応型カム式の後輪操舵装置を提
供することである。SUMMARY OF THE INVENTION An object of the present invention is to provide a steering angle-sensitive cam-type rear wheel steering device that has a simple configuration, is compact, and has excellent reliability and durability.

〔課題を解決するための手段］ 本発明に係る車両の後輪操舵装置は、前輪の操舵に応じ
て後輪を操舵する４輪操舵装置において、左右の後輪を
タイロッドを介して連結する１本の出力軸と、前輪の転
舵角に応じて出力軸と交差する方向の支軸回りに回動す
るカム部材と、上記出力軸に設けられ、カム部材の外周
面の左右両側部に当接する左右１対の当接部材と、上記
出力軸とカム部材と当接部材を収容するハウジングと、
上記カム部材を支持する支軸とハウジング間に介装され
、ハウジングに対して支軸を軸方向に規制するスラスト
軸受とを備えたものである。[Means for Solving the Problems] A rear wheel steering device for a vehicle according to the present invention is a four-wheel steering device that steers the rear wheels in accordance with the steering of the front wheels. a cam member that rotates around a support shaft in a direction that intersects the output shaft according to the steering angle of the front wheels; a pair of left and right contact members that contact each other; a housing that accommodates the output shaft, the cam member, and the contact member;
The cam member is provided with a thrust bearing that is interposed between the support shaft that supports the cam member and the housing, and that restricts the support shaft in the axial direction with respect to the housing.

（作用〕 本発明に係る後輪操舵装置においては、前輪の転舵角に
応じてカム部材が回転駆動され、カム部材が回転すると
カム部材の外周面の左右の両側部に当接している１対の
当接部材を介して出力軸が車幅方向へ移動駆動されて前
輪の転舵角とカム部材のカム特性に従って後輪が転舵さ
れる。(Function) In the rear wheel steering device according to the present invention, the cam member is rotationally driven according to the steering angle of the front wheels, and when the cam member rotates, the cam member contacts the left and right sides of the outer peripheral surface of the cam member. The output shaft is driven to move in the vehicle width direction via the pair of abutting members, and the rear wheels are steered according to the steering angle of the front wheels and the cam characteristics of the cam member.

この後輪操舵装置は、出力軸と当接部材とカム部材と支
軸などからなる簡単な構成であり、これらをハウジング
内に収容してユニット化できるので、車体への組付けの
面で有利である。This rear wheel steering device has a simple structure consisting of an output shaft, a contact member, a cam member, a support shaft, etc., and can be housed in a housing to form a unit, which is advantageous in terms of assembly to the vehicle body. It is.

上記カム部材を支持する支軸とハウジング間に支軸を軸
方向に規制するスラスト軸受を設けたので、ハウジング
に対する支軸の軸方向位置が変動せず、ハウジング内の
諸部品の機能が損なわれることがなく、支軸とハウジン
グ間に大きな摺動抵抗が生じることもない。Since a thrust bearing is provided between the support shaft that supports the cam member and the housing to restrict the support shaft in the axial direction, the axial position of the support shaft relative to the housing does not change, and the functions of various parts within the housing are impaired. Therefore, no large sliding resistance occurs between the support shaft and the housing.

〔発明の効果〕〔Effect of the invention〕

本発明に係る後輪操舵装置によれば、上記〔作用〕の項
で説明したように、少数の部品からなる簡単な構造のも
のになり、後輪操舵装置をハウジングを介してユニット
化することが出来る。According to the rear wheel steering device according to the present invention, as explained in the above [Function] section, it has a simple structure consisting of a small number of parts, and the rear wheel steering device can be integrated into a unit through a housing. I can do it.

更に、支軸とハウジング間にスラスト軸受を設けたこと
により、諸部品の機能を確保して信頼性を高め、支軸と
ハウジング間に大きな摺動抵抗が生じるのを防止し且つ
支軸とハウジングの摩耗を防止して耐久性を高めること
が出来る。Furthermore, by installing a thrust bearing between the support shaft and the housing, the function of various parts is ensured and reliability is increased, and large sliding resistance is prevented from occurring between the support shaft and the housing. It can prevent wear and increase durability.

更に、タイロンドから出力軸及びローラ部材を介してカ
ム部材に外力が作用してもカム部材に大きな回転モーメ
ントが作用することがないので、ステアリングハンドル
の操作が重くなることもない． 〔実施例〕 以下、本発明の実施例について図面を参照して説明する
。Furthermore, even if an external force is applied to the cam member from the tie rond via the output shaft and roller member, no large rotational moment is applied to the cam member, so the operation of the steering wheel does not become heavy. [Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

本実施例は、乗用自動車、マイクロバス、バス、小型ト
ラック及びトラックなどに適した４輪操舵装置における
後輪操舵装置に関するものであり、特に本実施例は自動
車の舵角感応型後輪操舵装置に本発明を適用した場合の
一例である。This embodiment relates to a rear wheel steering device in a four-wheel steering device suitable for passenger cars, microbuses, buses, small trucks, trucks, etc. In particular, this embodiment is applicable to a steering angle sensitive rear wheel steering device of an automobile. This is an example of the case where the present invention is applied.

第１図・第２図に示すように、自動車の４輪操舵装置は
、左右の前輪１を操舵する前輪操舵装置１０と、この前
輪操舵装置ｌＯに中間シャフト２３を介して連動連結さ
れて左右の後輪２を操舵する後輪操舵装置２０とを備え
ている。As shown in FIGS. 1 and 2, the four-wheel steering system of an automobile includes a front-wheel steering system 10 that steers left and right front wheels 1, and a front-wheel steering system 10 that is interlocked with this front-wheel steering system 10 via an intermediate shaft 23. and a rear wheel steering device 20 that steers the rear wheels 2 of the vehicle.

最初に、前輪操舵装置１０について説明する。First, the front wheel steering device 10 will be explained.

左右１対の前輪１は車幅方向に延びる操舵ロッド１３と
、操舵ロッドｌ３の両端に夫々連結された１対のタイロ
ッド１４を介して連結され、ステアリングハンドルｌ１
から延びたステアリングシャフトｌ２の下端にはビニオ
ン１５が連結され、ピニオンｌ５は操舵ロッドｌ３に形
成された主ラック１３ａに噛合している。従って、ステ
アリングハンドル１１を第１図にて矢印Ｆ１で示すよう
に左回り（反時計回り）に回動させると、ピニオン１５
を介して操舵ロッドｌ３が右方へ移動し、左右の前輪１
はキングビン（図示略）を中心として左回りに回動して
左旋回方向へ転舵され、上記と反対にステアリングハン
ドル１ｌを右回り（時計回り）に回動させると、左右の
前輪１は右回りに回動して右旋回方向へ転舵される。尚
、図示省略したが、ステアリングハンドル１１の操舵力
は周知の油圧式パワーステアリング機構によりパワーア
シストされるように構成されている。A pair of left and right front wheels 1 are connected via a steering rod 13 extending in the vehicle width direction and a pair of tie rods 14 connected to both ends of the steering rod l3, and a steering handle l1.
A pinion 15 is connected to the lower end of the steering shaft l2 extending from the steering shaft l2, and the pinion l5 meshes with a main rack 13a formed on the steering rod l3. Therefore, when the steering handle 11 is rotated to the left (counterclockwise) as shown by the arrow F1 in FIG.
The steering rod l3 moves to the right via the
rotates counterclockwise around the king bin (not shown) and is steered to the left turning direction.Contrary to the above, when the steering wheel 1l is rotated clockwise, the left and right front wheels 1 are turned to the right. It rotates around and is steered to the right direction. Although not shown in the drawings, the steering force of the steering handle 11 is configured to be power assisted by a well-known hydraulic power steering mechanism.

次に、後輪操舵装置２０について説明する。Next, the rear wheel steering device 20 will be explained.

上記操舵ロッド１３には車幅方向に延びる副ラック部材
２１が固着され、副ラック部材２ｌの下面には副ラック
が形成され、副ラック部材２ｌから後輪操舵装置２０に
亙って前後方向に延びる中間シャフト２３が設けられ、
中間シャフト２３の前端のピニオン２２は副ラック部材
２ｌの下面の副ラックに噛合し、中間シャフト２３の後
端部はカップリング２４により後輪操舵装置２０の入力
軸２５に連結されている。従って、ステアリングハンド
ル１ｌを矢印Ｆ１方向へ操作すると、中間シャフト２３
は矢印Ｆ２のように後方より視て時計回りに回動し、中
間シャフト２３の回転角はステアリングハンドル１１の
回転角に比例する前輪１の転舵角に比例している。A sub-rack member 21 extending in the vehicle width direction is fixed to the steering rod 13, and a sub-rack is formed on the lower surface of the sub-rack member 2l, extending from the sub-rack member 2l to the rear wheel steering device 20 in the longitudinal direction. An extending intermediate shaft 23 is provided;
The pinion 22 at the front end of the intermediate shaft 23 meshes with the sub rack on the lower surface of the sub rack member 2l, and the rear end portion of the intermediate shaft 23 is connected to the input shaft 25 of the rear wheel steering device 20 by a coupling 24. Therefore, when the steering handle 1l is operated in the direction of arrow F1, the intermediate shaft 23
rotates clockwise as seen from the rear as indicated by an arrow F2, and the rotation angle of the intermediate shaft 23 is proportional to the turning angle of the front wheels 1, which is proportional to the rotation angle of the steering handle 11.

上記後輪操舵装置２０は、左右の後輪２間の差動歯車装
置３と左右のアクスルケーシング４よりも少し後方且つ
上方に車幅方向に向けて配設され、後輪操舵装置２０の
出力軸２６（第４図・第５図参照）の両端部には夫々ポ
ールジョイト２７（第４図・第５図参照）を介して左右
１対のタイロツド２日が連結され、各タイロッド２８の
外端部は後輪２のホイール支持部材５の後側部のブラケ
ット６に鉛直のビン７を介して回動自在に連結され、ホ
イール支持部材５はアクスルケーシング４の外端部に略
鉛直方向のビン部材を介して回動自在に連結されている
。従って、後輪操舵装置２０の出力軸２６が矢印Ｆ，で
示すように左方へ駆動され″ると後輪２は第１図にて時
計回りに左旋回方向へ転舵され、また出力軸２６が右方
へ駆動されると左右の後輪２は反時計回りに右旋回方向
へ転舵される． ここで、後輪操舵装置２０の構造の詳細について、第４
図〜第１０図を参照して説明する。The rear wheel steering device 20 is disposed toward the vehicle width direction slightly behind and above the differential gear device 3 between the left and right rear wheels 2 and the left and right axle casings 4, and outputs an output of the rear wheel steering device 20. A pair of left and right tie rods are connected to both ends of the shaft 26 (see Figs. 4 and 5) via pole joints 27 (see Figs. 4 and 5), respectively. The outer end is rotatably connected to the bracket 6 on the rear side of the wheel support member 5 of the rear wheel 2 via a vertical pin 7, and the wheel support member 5 is connected to the outer end of the axle casing 4 in a substantially vertical direction. are rotatably connected via a bottle member. Therefore, when the output shaft 26 of the rear wheel steering device 20 is driven to the left as shown by the arrow F, the rear wheels 2 are steered clockwise in FIG. When the rear wheel steering device 26 is driven to the right, the left and right rear wheels 2 are steered counterclockwise in the right turning direction.
This will be explained with reference to FIGS.

下部ハウジング３０と上部ハウジング３ｌとからなる中
空のハウジング２９内には、車幅方向に水平に延びる１
本の出力軸２６が左右方向に移動可能に配設され、出力
軸２６は左右１対のロツド部３２Ｌ・３２Ｒと、各ロッ
ド部３２Ｌ・３２Ｒの内端部に一体形成された左右１対
の二又状のローラ枢支部３３Ｌ・３３Ｒと、これらロー
ラ枢支部３３Ｌ・３３Ｒの後側の腕部３５ａ同士を連結
しローラ枢支部３３Ｌ・３３Ｒに一体形成された連結軸
部３４とからなる。各ローラ枢支部３３Ｉ７・３３Ｒは
前後１対の腕部３５ａ・３５ｂを有し、第４図において
右方に開口する左側のローラ枢支部３３Ｌには前後の腕
部３５ａ・３５ｂに両端支持された前後方向向きの水平
の枢支軸３６によりローラ３７Ｌが回転自在に枢着され
、また左方に開口する右側のローラ枢支部３３Ｒには前
後の腕部３５ａ・３５ｂに両端支持された前後方向向き
の水平の枢支軸３６によりローラ３７Ｒが回転自在に框
着されている。Inside the hollow housing 29 consisting of the lower housing 30 and the upper housing 3l, there is a housing 1 extending horizontally in the vehicle width direction.
A book output shaft 26 is disposed to be movable in the left and right direction, and the output shaft 26 has a pair of left and right rod portions 32L and 32R, and a pair of left and right rod portions 32L and 32R integrally formed at the inner end of each rod portion 32L and 32R. It consists of forked roller pivot parts 33L and 33R, and a connecting shaft part 34 that connects the rear arm parts 35a of these roller pivot parts 33L and 33R and is integrally formed with the roller pivot parts 33L and 33R. Each roller pivot 33I7, 33R has a pair of front and rear arms 35a, 35b, and the left roller pivot 33L, which opens to the right in FIG. 4, has both ends supported by the front and rear arms 35a, 35b. A roller 37L is rotatably attached to a horizontal pivot shaft 36 facing in the front-rear direction, and a roller 37L facing in the front-rear direction is supported at both ends by the front and rear arms 35a and 35b on the right roller pivot 33R that opens to the left. A roller 37R is rotatably mounted on a horizontal pivot shaft 36.

上記左右のローラ３７Ｌ・３７Ｒの間には、鉛直方向向
き板状のカム部材３８が配設され、カム部材３８の外周
面の左右の両側部が夫々対応するローラ３７Ｌ・３７Ｒ
に当接され、出力軸２６の１対のロッド部３２Ｌ・３２
Ｒと１対のローラ３７Ｌ・３７Ｒとカム部材３８とは平
面視にて直線状の同一軸線上に配置され、出力軸２６の
１対のロッド部３２Ｌ・３２Ｒと１対のローラ３７Ｌ・
３７Ｒとカム部材３８の中心部は正面視にて直線状の同
一軸線上に配置されている。上記カム部材３８の中心部
には前後方向向きの水平の支軸３９が内嵌押通され、支
軸３９の前端部はラジアル軸受４０を介して下部ハウジ
ング３０の軸孔に支持され、また支軸３９の後端部はラ
ジアル軸受４１を介して上部ハウジング３ｌの軸孔に支
持され、カム部材３８と支軸３９間にはキー４２が介装
され、カム部材３８は支軸３９と共に支軸３９を中心と
して回転可能である。支軸３９の前端部の小？ｋ軸部３
　９　ａは下部ハウジング３０のキャップ状突出部３０
ｃの孔を挿通して前方へ延出し、突出部３０ｃの内側と
外側にスラスト軸受４３・４４が装着され、外側のスラ
スト軸受４４は小径軸部３９ａに螺合されたナット４５
とロックナット４６とで保持され、内側のスラスト軸受
４３は支軸３９の環状端面に当接している。従って、支
軸３９は１対のスラスト軸受４３・４４により軸方向に
移動しないように規制されている。上記支軸３９の後端
側部分は連結軸部３４に形成された左右方向に細長いガ
イド孔４７に挿通され、支軸３９はガイド孔４７の上下
両面に当接している。従って、連結軸部３４を含む出力
軸２６は支軸３９に対して相対的に左右方向へ移動可能
であるが、上下方向には相対移動しないようになってい
る。A vertical plate-shaped cam member 38 is disposed between the left and right rollers 37L and 37R, and the left and right sides of the outer peripheral surface of the cam member 38 correspond to the corresponding rollers 37L and 37R, respectively.
The pair of rod portions 32L and 32 of the output shaft 26
R, the pair of rollers 37L and 37R, and the cam member 38 are arranged on the same linear axis in plan view, and the pair of rod parts 32L and 32R of the output shaft 26 and the pair of rollers 37L and 37R are arranged on the same linear axis in plan view.
The center portions of the cam member 37R and the cam member 38 are arranged on the same linear axis when viewed from the front. A horizontal support shaft 39 facing in the front-rear direction is inserted into the center of the cam member 38, and the front end of the support shaft 39 is supported in the shaft hole of the lower housing 30 via a radial bearing 40. The rear end of the shaft 39 is supported in the shaft hole of the upper housing 3l via a radial bearing 41, a key 42 is interposed between the cam member 38 and the support shaft 39, and the cam member 38 and the support shaft 39 are connected to each other. It is rotatable around 39. Is the front end of the support shaft 39 small? k-axis section 3
9 a is the cap-shaped protrusion 30 of the lower housing 30;
Thrust bearings 43 and 44 are installed on the inside and outside of the protruding portion 30c, and the outer thrust bearing 44 has a nut 45 screwed onto the small diameter shaft portion 39a.
and a lock nut 46, and the inner thrust bearing 43 is in contact with the annular end surface of the support shaft 39. Therefore, the support shaft 39 is restricted from moving in the axial direction by a pair of thrust bearings 43 and 44. The rear end portion of the support shaft 39 is inserted into a guide hole 47 formed in the connecting shaft portion 34 and elongated in the left-right direction, and the support shaft 39 is in contact with both the upper and lower surfaces of the guide hole 47. Therefore, the output shaft 26 including the connecting shaft portion 34 is movable in the horizontal direction relative to the support shaft 39, but is not allowed to move relative to the vertical direction.

上記カム部材３８の外周面と１対のローラ３７Ｌ・３７
Ｒ間に隙間が生じるのを防止する為、１対のローラ３７
Ｌ・３７Ｒの何れか一方（本実施例では左側のローラ３
７Ｌ）は、前後１対の硬いラバープッシュ５０を介して
ローラ枢支部３３Ｌに取付けられている。The outer peripheral surface of the cam member 38 and the pair of rollers 37L and 37
A pair of rollers 37 is used to prevent gaps from forming between R.
Either one of L or 37R (in this example, the left roller 3
7L) is attached to the roller pivot portion 33L via a pair of front and rear hard rubber pushers 50.

第７図に示すように、ローラ３７Ｌは枢支軸３６に圧人
されたスリーブ５１とスリーブ５ｌに外嵌された軸受メ
タル５２を介して枢支軸３６に装着され、枢支軸３６の
両端側部分にはスリーブ５１の位置を規制するカラ−５
３が外嵌され、各カラー５３と腕部３５ａ・３５ｂの枢
支孔の内周面５４間の環状のスペースには環状のラバー
プッシュ５０が圧縮状態に装着されている。上記ラバー
プッシュ５０は、例えば第８図に示すように金属製の内
筒５０ａと金属製の外筒５０ｃ間に、プリロードを加え
て圧縮状態にした硬いラバーフッシュ本体５０ｂを組込
んで接着したもので、このラバープッシュ５０は後輪２
からタイロンド２８と出力軸２６を介してローラ３７Ｌ
・３７Ｒに作用する荷重に耐え得るものとなっている。As shown in FIG. 7, the roller 37L is attached to the pivot shaft 36 via a sleeve 51 pressed onto the pivot shaft 36 and a bearing metal 52 externally fitted on the sleeve 5l. A collar 5 for regulating the position of the sleeve 51 is provided on the side part.
3 is fitted onto the outside, and an annular rubber pusher 50 is mounted in a compressed state in an annular space between each collar 53 and the inner circumferential surface 54 of the pivot hole of the arm portions 35a and 35b. The rubber push 50 is, for example, as shown in FIG. 8, a hard rubber bush main body 50b compressed by applying a preload is assembled and bonded between a metal inner cylinder 50a and a metal outer cylinder 50c. So, this rubber push 50 is rear wheel 2
from the roller 37L via the tie rond 28 and the output shaft 26.
・It is capable of withstanding the load that acts on 37R.

上記カム部材３８を前輸１の転舵角に応じて回動させる
ため、ハウジング２９内で支軸３９には平歯車５５が固
着され、平歯車５５の右側下部に噛合する小径のピニオ
ン５６が設けられ、ピニオン５６は入力軸２５の後端部
に固着され、入力軸２５ば下部ハウジング３０のボス部
３０ｂを挿通して前方へ延出し、入力軸２５の前端部は
カップリング２４により中間シャフト２３の後端部に一
体的に回動するように連結され、入力軸２５はボス部３
０ｂで回転自在に支持され、第６図に示すように、入力
軸２５の外周の環状溝５７に規制ピン５８を係合させる
ことにより入力軸２５は前後方向に移動しないように規
制されている。In order to rotate the cam member 38 according to the steering angle of the front wheel 1, a spur gear 55 is fixed to the support shaft 39 within the housing 29, and a small diameter pinion 56 meshes with the lower right side of the spur gear 55. The pinion 56 is fixed to the rear end of the input shaft 25, and the input shaft 25 extends forward through the boss portion 30b of the lower housing 30. The front end of the input shaft 25 is connected to the intermediate shaft by the coupling 24. The input shaft 25 is connected to the rear end portion of the boss portion 3 so as to rotate integrally with the rear end portion of the boss portion 3.
0b, and as shown in FIG. 6, the input shaft 25 is restricted from moving in the front-rear direction by engaging a restriction pin 58 in an annular groove 57 on the outer periphery of the input shaft 25. .

上記中間シャフト２３は、副ラックとピニオン２２を介
してステアリングシャフトｌ２の回転に対して所定の減
速比で減速され、平歯車５５は中間シャフト２３の回転
に対して（ビニオン５６の直径）／（平歯車５５の直径
）の減速比で減速される。The intermediate shaft 23 is reduced in speed by a predetermined reduction ratio with respect to the rotation of the steering shaft l2 via the auxiliary rack and pinion 22, and the spur gear 55 is reduced in speed with respect to the rotation of the intermediate shaft 23 by (diameter of pinion 56)/( The speed is reduced by the reduction ratio of the spur gear 55 (diameter).

従って、上記カム部材３８は、ステアリングハンドル１
ｌの操舵角に比例する前輪１の転舵角に比例して回動さ
れ、ステアリングハンドル１ｌを第１図の矢印Ｆ１の方
向へ操作したときはカム部材３８は後方より視て反時計
回り（第５図で矢印Ｆ４の方向）に回動され、またステ
アリングハンドル１１を矢印Ｆ１と反対方向へ操作した
ときには上記の反対方向へ回動される。Therefore, the cam member 38 is attached to the steering handle 1.
The cam member 38 is rotated in proportion to the steering angle of the front wheels 1, which is proportional to the steering angle of the front wheels 1, and when the steering wheel 1l is operated in the direction of the arrow F1 in FIG. When the steering wheel 11 is operated in the direction opposite to the arrow F1, the steering wheel is rotated in the opposite direction.

ここで、上記カム部材３８の形状について説明する． 第１０図は、カム部材３日・と１対ローラ３７Ｌ・３７
Ｒとの相対位置関係を後方より視て図示したものである
． カム部材３８は後方より視たときに左右対称であり、前
輪ｌの転舵角が零のときカム部材３８は第１０図に実線
で図示の中立状態となり、左側のローラ３７Ｌは点Ｐ０
に当接しまた右側のローラ３７Ｒは点Ｑ０に当接してい
る。カム部材３８の外周面の左右両側部には、第１カム
面６１とこの第１カム面６ｌの上端から上方へ連なる第
２カム面６２と第１カム面６ｌの下端から下方へ連なる
第３カム面６３とが夫々形成され、第１カム面６１と第
２カム面６２と第３カム面６３の範囲が操？範囲である
． 上記第１カム面６Ｉぱ、反対側の第１カム面６１と協働
して機能し、ステアリングハンドル１１が左回り又は右
回りに例えば２００度（これは、前輪ｌの転舵角θ，＝
１５度に対応する）以下の範囲で操舵されるときに、後
輪２を転舵しない中立状態に保持する為のものである。Here, the shape of the cam member 38 will be explained. Figure 10 shows a cam member 3 days and a pair of rollers 37L and 37.
This is a diagram showing the relative positional relationship with R as seen from the rear. The cam member 38 is symmetrical when viewed from the rear, and when the steering angle of the front wheel l is zero, the cam member 38 is in a neutral state as shown by the solid line in FIG. 10, and the left roller 37L is at the point P0.
The roller 37R on the right side is in contact with point Q0. On both left and right sides of the outer peripheral surface of the cam member 38, a first cam surface 61, a second cam surface 62 extending upward from the upper end of the first cam surface 6l, and a third cam surface 62 extending downward from the lower end of the first cam surface 6l are provided. Cam surfaces 63 are respectively formed, and the ranges of the first cam surface 61, the second cam surface 62, and the third cam surface 63 are operable. It is a range. The first cam surface 6I functions in cooperation with the first cam surface 61 on the opposite side, so that the steering wheel 11 can be rotated counterclockwise or clockwise by, for example, 200 degrees (this is the steering angle θ,=
This is to maintain the rear wheels 2 in a neutral state in which they are not steered when the wheels are steered in the range below (corresponding to 15 degrees).

第１カム面６ｌは支軸３９の中心Ｏを中心とする半径Ｒ
の円筒面（つまり、円弧Ｐ，Ｐ■からなる円筒面）であ
り、これが例えばステアリングハンドル１１を左回り又
は右回りに２００度合計４００度操舵する範囲に対応し
、ステアリングハンドル１１を左回りに２００度操舵す
ると、カム部材３８は矢印Ｆ，の方向へ回転して左側の
ローラ３７Ｌが点Ｐ，にまた右側のローラ３７Ｒが点Ｑ
２に夫々当接し、ステアリングハンドル１１を右回りに
２００度操舵すると、カム部材３８は矢印Ｆｓと反対方
向へ回転して左側のローラ３７Ｌが点Ｐ！にまた右側の
ローラ３７Ｒが点Ｑ１に夫々当接する。The first cam surface 6l has a radius R centered on the center O of the support shaft 39.
is a cylindrical surface (that is, a cylindrical surface consisting of arcs P and P), and this corresponds to a range in which the steering wheel 11 is steered, for example, by 200 degrees counterclockwise or clockwise, for a total of 400 degrees, and when the steering wheel 11 is turned counterclockwise. When the steering is performed 200 degrees, the cam member 38 rotates in the direction of arrow F, and the left roller 37L moves to point P, and the right roller 37R moves to point Q.
When the steering wheel 11 is rotated 200 degrees clockwise, the cam member 38 rotates in the direction opposite to the arrow Fs, and the left roller 37L moves to the point P! Also, the right roller 37R comes into contact with the point Q1.

上記第２カム面６２は反対側の第３カム面６３と協働し
て機能し、第３カム面６３は反対側の第２カム面６２と
協働して機能し、第２カム面６２と第３カム面６３はス
テアリングハンドル１ｌを左回り又は右回りに２００度
より大きく操舵したときつまり前輪１の転舵角θ，が１
５度より大きくなったときに、（θｒ　　　１５）の角
度に比例して後輪２を前輪１と逆相に転舵させる為のも
のである。The second cam surface 62 functions in cooperation with a third cam surface 63 on the opposite side, and the third cam surface 63 functions in cooperation with the second cam surface 62 on the opposite side, and the second cam surface 62 functions in cooperation with the second cam surface 62 on the opposite side. and the third cam surface 63, when the steering wheel 1l is steered counterclockwise or clockwise by more than 200 degrees, that is, the steering angle θ of the front wheels 1 is 1.
This is to steer the rear wheels 2 in the opposite phase to the front wheels 1 in proportion to the angle (θr 15) when the angle is greater than 5 degrees.

第２カム面６２は、曲線ＰＩＦ３で決定される曲面であ
り、点Ｐ，から点Ｐ，に向って中心Ｏからの半径が漸増
していぐ。The second cam surface 62 is a curved surface determined by a curve PIF3, and the radius from the center O gradually increases from point P to point P.

第３カム面６３は、曲線ＰｔＰ＝で決定される曲面であ
り、点Ｐ２から点Ｐ４に向って中心０がらの半径が漸減
していく．そして、直径Ｐ＋Ｑｚ＝直径Ｐ３Ｑ４＝２Ｒ
であり、点ｐ．と点Ｐ３間の点から点Ｑ２と点Ｑ４間の
対応する点までの直径も２Ｒとなっている。このことは
、曲線Ｐ．Ｐ４間の第３カム面６３と曲線Ｑ．Ｑ，間の
第２カム面６２との関係においても同様である。左側の
ローラ３７Ｌが点Ｐ３に当接したときに右側のローラ３
７Ｒが点Ｑ４に当接し、左側のローラ３７Ｌが点Ｐ４に
当接したときに右側のローラ３７Ｒが点Ｑ，に当接する
。従って、カム部材３８が操舵範囲内で回転する限り左
側のローラ３７Ｌと右側のローラ３７Ｒとは常にカム部
材３日の外周面に当接することになる。但し、操舵範囲
のうら点Ｐ３の近傍部分と点Ｐ４の近傍部分は実際には
殆んど使用しない範囲である。The third cam surface 63 is a curved surface determined by the curve PtP=, and the radius from the center 0 gradually decreases from point P2 to point P4. And diameter P+Qz=diameter P3Q4=2R
, and the point p. The diameter from the point between and point P3 to the corresponding point between point Q2 and point Q4 is also 2R. This means that the curve P. The third cam surface 63 between P4 and the curve Q. The same applies to the relationship with the second cam surface 62 between Q and Q. When the left roller 37L comes into contact with point P3, the right roller 3
7R contacts point Q4, and when the left roller 37L contacts point P4, the right roller 37R contacts point Q. Therefore, as long as the cam member 38 rotates within the steering range, the left roller 37L and the right roller 37R always come into contact with the outer peripheral surface of the cam member 3. However, the portion near the rear point P3 and the portion near the point P4 of the steering range are ranges that are hardly used in practice.

第１１図は上記カム部材３８などにより決定される後輪
操舵装置２０の特性を、前輪ｌの転舵角θ，を横軸にま
た後輪２の転舵角θアを縦軸にとって表わしたものであ
り、θ，。は例えばθ，。−１５度である。FIG. 11 shows the characteristics of the rear wheel steering device 20 determined by the cam member 38, etc., with the steering angle θ of the front wheels 1 on the horizontal axis and the steering angle θa of the rear wheels 2 on the vertical axis. and θ,. For example, θ,. -15 degrees.

上記カム部材３日を左右１対のローラ３７Ｌ・３７Ｒ間
に組込むときに容易に組込み得るようにする為、カム部
材３８の外周面の操舵範囲外の部分においては、カム部
材３８の直径が２Ｒよりも短かく形成されている。点Ｐ
３から点Ｑ，まで直径Ｐ．Ｑ．と平行に直線的に形成さ
れ、直径Ｐ，Ｐ６は２Ｒより著しく短かく形成され、点
Ｐ３と点Ｐｓ間の点から点Ｑ４と点Ｐ．間の点までの直
径も２Ｒよりもかなり短かく形成され、第１０図に示す
中立状態のときのカム部材３８の全高も２Ｒより著しく
短かく形成されている。In order to easily assemble the cam member 38 between the left and right pair of rollers 37L and 37R, the diameter of the cam member 38 is 2R in the portion of the outer peripheral surface of the cam member 38 outside the steering range. It is formed shorter than the Point P
3 to point Q, the diameter P. Q. The diameters P and P6 are formed to be significantly shorter than 2R, and from the point between the point P3 and the point Ps to the point Q4 and the point P. The diameter up to the point in between is also formed to be much shorter than 2R, and the total height of the cam member 38 in the neutral state shown in FIG. 10 is also formed to be much shorter than 2R.

次に、ハウジング２９の構造について第９図により説明
する。Next, the structure of the housing 29 will be explained with reference to FIG. 9.

ハウジング２９内に出力軸２６、カム部材３８、平歯車
５５及びビニオン５６等を組込む為にハウジング２９は
合せ面６０で分割される下部ハウジング３０と上部ハウ
ジング３１とで中空状に形成される。本実施例のハウジ
ング２９においては、合せ面６０の方向について次のよ
うな工夫が凝らされている。In order to incorporate the output shaft 26, cam member 38, spur gear 55, pinion 56, etc. into the housing 29, the housing 29 is formed into a hollow shape with a lower housing 30 and an upper housing 31 separated by a mating surface 60. In the housing 29 of this embodiment, the following measures have been taken regarding the direction of the mating surface 60.

自動車の走行時、特にコーナリングする場合など、後輪
２からタイロッド２８に数１００ｋｇの軸力が作用して
タイロッド２８から出力軸２６の端部に作用し、タイロ
ッド２８は出力軸２６に対して前方且つ下方へ傾いてい
るので、車体に固定されたハウジング２９には出力軸２
６から軸力の分力ＲＦが第９図に示すような方向に作用
する。When a car is running, especially when cornering, an axial force of several hundred kilograms acts from the rear wheels 2 to the tie rod 28 and from the tie rod 28 to the end of the output shaft 26, causing the tie rod 28 to move forward with respect to the output shaft 26. In addition, since it is tilted downward, the output shaft 2 is attached to the housing 29 fixed to the vehicle body.
A component force RF of the axial force from 6 acts in the direction shown in FIG.

一方、タイロンド２８から出力軸２６に伝達される軸力
によりローラ３７Ｌ・３７Ｒを介してカム部材３８に回
転モーメントが作用し、その１対の反力ＭＦが第９図に
示す鉛直面６４内で出力軸２６からハウジング２９に作
用する。／’％ウジング２９内に前記の諸部品を組込む
為には、合せ面６０を鉛直方向に向けるのが一般的であ
るが、上記分力ＲＦと反力ＭＦに鑑みると好ましくない
。そこで、上記ハウジング２９の合せ面６０は出力軸２
６からハウジング２９に作用する上記分力ＲＦ及び反力
ＭＦの方向と交差するように、出力軸２６の軸心ＡＣを
含む傾斜面であって、鉛直面に対して約４５度傾斜の前
方上りの傾斜面に形成されている。上記合せ面６０に沿
って下部ノλウジング３０の外周縁と上部ハウジング３
１の外周縁には夫々フランジ部３０ａ・３１ａが形成さ
れ、これらフランジ部３０ａ・３１ａ同士は複数のボノ
レト６５で固着されている。このような合せ面６０とし
たので、前記諸部品を容易に組込み、比較的小形のフラ
ンジ部３０ａ・３１ａ及びボルト６５により分力ＲＦと
力ＭＦとに対して十分な強度にすることが出来る。尚、
ロッド部３２Ｌ・３２Ｒの外端部分とボールジョイント
２７とタイロンド２８の内端部はラバー製の蛇腹状部材
４７で覆われている。On the other hand, a rotational moment acts on the cam member 38 via the rollers 37L and 37R due to the axial force transmitted from the tie rond 28 to the output shaft 26, and the pair of reaction forces MF are generated within the vertical plane 64 shown in FIG. It acts on the housing 29 from the output shaft 26. /'% In order to incorporate the above-mentioned parts into the housing 29, it is common to orient the mating surface 60 in the vertical direction, but this is not preferable in view of the component force RF and reaction force MF. Therefore, the mating surface 60 of the housing 29 is connected to the output shaft 2.
An inclined surface including the axis AC of the output shaft 26 so as to intersect with the direction of the component force RF and reaction force MF acting on the housing 29 from 6 to the housing 29, and is inclined at an angle of about 45 degrees with respect to the vertical plane. It is formed on an inclined surface. Along the mating surface 60, the outer peripheral edge of the lower λ housing 30 and the upper housing 3
Flange portions 30a and 31a are formed on the outer circumferential edge of 1, respectively, and these flange portions 30a and 31a are fixed to each other by a plurality of bolts 65. With such a mating surface 60, the various parts mentioned above can be easily assembled, and the comparatively small flange portions 30a, 31a and the bolts 65 can provide sufficient strength against the component force RF and force MF. still,
The outer end portions of the rod portions 32L and 32R and the inner end portions of the ball joint 27 and tie rond 28 are covered with a bellows-like member 47 made of rubber.

以上のように構成された自動車の後輪操舵装置の作用に
ついて説明する。The operation of the automobile rear wheel steering system configured as described above will be explained.

既述のように、ステアリングハンドル１１を第１図の矢
印Ｆ１の方へ抛舵すると、前輪ｌの転舵角に応じてカム
部材３８が第ｌＯ図の矢印Ｆ，の方へ回転し、またステ
アリングハンドル１１を上記と反対方向へ操舵するとカ
ム部材３８も上記と反対方向へ回転する。As mentioned above, when the steering wheel 11 is steered in the direction of the arrow F1 in FIG. 1, the cam member 38 rotates in the direction of the arrow F in FIG. When the steering handle 11 is steered in the opposite direction, the cam member 38 also rotates in the opposite direction.

前輪１の転舵角が左旋回方向また右旋回方向へ１５度以
内のときにはローラ３７Ｌ・３７Ｒはカム部材３８の等
半径の第１カム面６１上を転動するので、ローラ３７Ｌ
と３７Ｒとは中心０に対して対称に位置し、後輪２は転
舵されず中立状態を保持する。When the steering angle of the front wheel 1 is within 15 degrees in the left turning direction or right turning direction, the rollers 37L and 37R roll on the first cam surface 61 of the cam member 38 with the same radius, so the roller 37L
and 37R are located symmetrically with respect to the center 0, and the rear wheels 2 are not steered and maintain a neutral state.

前輪１が左旋回方向へ１５度以上転舵されると、ローラ
３７Ｌは左側の第２カム面６２上を転勤し、ローラ３７
Ｒは右側の第３カム面６３上を転勤する．その結果、中
心Ｏからローラ３７Ｌまでの半径が中心Ｏからローラ３
７Ｒまでの半径よりも大きくなるので、出力軸２６は左
方へ移動し、１対のタイロッド２８を介して１対の後輪
２は左旋回方向（第１図で時計回り方向）へ転舵される
。When the front wheel 1 is turned to the left by 15 degrees or more, the roller 37L moves on the second cam surface 62 on the left side, and the roller 37L moves on the second cam surface 62 on the left side.
R moves on the third cam surface 63 on the right side. As a result, the radius from center O to roller 37L is
Since the radius becomes larger than the radius up to 7R, the output shaft 26 moves to the left, and the pair of rear wheels 2 are steered to the left turning direction (clockwise in Fig. 1) via the pair of tie rods 28. be done.

前輪１が右旋回方向へ１５度以上転舵されると、ローラ
３７Ｌが左側の第３カム面６３上を転勤し、ローラ３７
Ｒは右側の第２カム面６２上を転勤する。その結果、中
心０からローラ３７Ｌまでの半径が中心Ｏからローラ３
７Ｒまでの半径よりも／Ｊ％さくなるので、出力軸２６
は右方へ移動し、１対のタイロッド２８を介して１対の
後輪２番よ右旋回方向（第１図で反時計回り方向）へ転
舵される。When the front wheel 1 is steered by 15 degrees or more in the right turning direction, the roller 37L moves on the third cam surface 63 on the left side, and the roller 37L moves on the left third cam surface 63.
R moves on the second cam surface 62 on the right side. As a result, the radius from center 0 to roller 37L is
Since the radius is /J% smaller than the radius up to 7R, the output shaft 26
moves to the right and is steered by the pair of rear wheels No. 2 via the pair of tie rods 28 in the right turning direction (counterclockwise in FIG. 1).

このように、ステアリング／’％ンドノレｌ１を左回り
又は右回りに２００度以上転舵して、前輪１力｛１５度
以上転舵されると、後輸２は前輪１の転舵と逆位相で転
舵されることになる。In this way, if the steering wheel 1 is turned counterclockwise or clockwise by more than 200 degrees and the front wheel 1 is turned by more than 15 degrees, the rear wheel 2 will be in the opposite phase to the steering of the front wheel 1. The ship will be steered.

但し、後輪２の転舵角θ８は（θＦ　　１５）に比例す
るものの、後輪２の転舵角θ．は最大でも約１０度程度
である。However, although the steering angle θ8 of the rear wheels 2 is proportional to (θF 15), the steering angle θ. is about 10 degrees at most.

自動車の走行時、既述のようにタイロッド２８から出力
軸２６へ大きな軸力が作用するが、出力軸２６の１対の
ロッド部３２Ｌ・３２Ｒと１対のローラ３７Ｌ・３７Ｒ
とカム部材３８は同一軸線上に配置されているので、上
゜記軸力は主として部材同士間で圧縮力で伝達され、何
れの部材にも大きな曲げモーメントが生じることがない
。枢支軸３６は両端支持されているので、枢支軸３６に
も大きな曲げモーメントは生じない。カム部材３８の左
右両側部にローラ３７Ｌ・３７Ｒが当接するので、支軸
３９に対してカム部材３８から力が殆んど作用しない。When the car is running, a large axial force is applied from the tie rod 28 to the output shaft 26 as described above, but a large axial force acts on the output shaft 26 between the pair of rod parts 32L and 32R and the pair of rollers 37L and 37R.
Since the cam member 38 and the cam member 38 are arranged on the same axis, the above-mentioned axial force is mainly transmitted between the members as a compressive force, and no large bending moment is generated in any member. Since the pivot shaft 36 is supported at both ends, no large bending moment is generated on the pivot shaft 36 either. Since the rollers 37L and 37R are in contact with the left and right sides of the cam member 38, almost no force is applied from the cam member 38 to the support shaft 39.

従って、出力軸２６、カム部材３日及び支軸３９などの
諸部材を極力小型化して小型・軽量であって簡単な構造
の後輪操舵装置２０を実現することが出来る。しかも、
出力軸２６は一本の部材なので、左右の後輪２の転舵は
確実に同期する。Therefore, it is possible to minimize the size of various members such as the output shaft 26, the cam member 3, and the support shaft 39, thereby realizing the rear wheel steering device 20 that is small, lightweight, and has a simple structure. Moreover,
Since the output shaft 26 is a single member, the steering of the left and right rear wheels 2 is reliably synchronized.

前記ラバープッシュ５０はローラ３７Ｌとローラ枢支部
３３Ｌ間にのみ介装され、ローラ３７Ｒとローラ枢支部
３３Ｒ間には介装されていない。The rubber push 50 is interposed only between the roller 37L and the roller pivot 33L, and is not interposed between the roller 37R and the roller pivot 33R.

仮に、両ローラ３７Ｌ・３７Ｒにラバープッシュ５０を
設けた場合には、長期間使用している間にラバープッシ
ュ５０が劣化したときに、両方のラバーブンシュ５０の
弾性力が異なってカム部材３８に対して出力軸２６が左
方または右方へ微小Ｇこ変位し、中立状態のときの後輪
２のアライメントに狂いが生じてしまう。If rubber pushers 50 are provided on both rollers 37L and 37R, if the rubber pushers 50 deteriorate during long-term use, the elastic force of both rubber bunches 50 will be different and the elastic force will be different and the rubber pushers 50 will not be able to move against the cam member 38. As a result, the output shaft 26 is slightly displaced leftward or rightward by a slight G force, causing misalignment of the rear wheels 2 in the neutral state.

本実施例においては、一方のローラ３７Ｌにのみラバー
プッシュ５０を設けるので、ラノマーフ゛ツシュ５０の
弾性力が変動しても、カム部材３８と出力軸２６の位置
関係は、ラバーブ・ンシュ５０を設けない方のローラ３
７Ｒを介して常に一定に設定されるので、中立状態のと
きの後輪２のアライメントに狂いが生じることがない。In this embodiment, since the rubber push 50 is provided only on one roller 37L, even if the elastic force of the lanomar bush 50 changes, the positional relationship between the cam member 38 and the output shaft 26 is the same as that without the rubber push 50. roller 3
Since it is always set constant via 7R, the alignment of the rear wheel 2 in the neutral state will not be out of alignment.

前記ラバープッシュ５０はプリロードを負荷した状態で
組込まれることから、左右のローラ３７Ｌ・３７Ｒ間に
カム部材３８を組込むのが非常Ｇこ難しい。このカム部
材３８の組込みを容易にする為に、既述のようにカム部
材３８の操舵範囲外の直径（例えば、第１０図の直径Ｐ
，Ｐ６　）が２Ｒよりも著しく短かく形成されている。Since the rubber pusher 50 is assembled with a preload applied, it is extremely difficult to assemble the cam member 38 between the left and right rollers 37L and 37R. In order to facilitate the assembly of the cam member 38, the diameter of the cam member 38 outside the steering range (for example, the diameter P in FIG.
, P6) is formed significantly shorter than 2R.

支軸３９が組付けられたカム部材３８を、ハウジング２
９外で予め出力軸２６に組付ける場合、前方より視た第
１２図〜第１４図に示すように、カム部材３８を中立状
態から９０度回転させた姿勢にして、支軸３９の後端部
をガイド孔４７に挿入する．このとき、寸法Ｌは２Ｒよ
りも十分に小さいので、第１３図のように簡単に組込む
ことが出来る。次に、支軸３９とともにカム部材３８を
第１３図にて時計回り方向に回動させていくと、ローラ
３７Ｌが第３カム面６３と第１カム面６１上を転勤し、
ローラ３７Ｒが第２カム面６２と第１カム面６１上を転
動するので、極めて簡単に第１４図の状態に組付けるこ
とが出来る。The cam member 38 on which the support shaft 39 is assembled is attached to the housing 2.
When assembling the cam member 38 to the output shaft 26 in advance outside of 9, the cam member 38 is rotated 90 degrees from the neutral state as shown in FIGS. into the guide hole 47. At this time, since the dimension L is sufficiently smaller than 2R, it can be easily assembled as shown in FIG. Next, when the cam member 38 is rotated clockwise in FIG. 13 together with the support shaft 39, the roller 37L moves on the third cam surface 63 and the first cam surface 61.
Since the roller 37R rolls on the second cam surface 62 and the first cam surface 61, it can be assembled into the state shown in FIG. 14 very easily.

次に、平歯車５５及び軸受４０・４ｌ・４３・４４を支
軸３９に組付けてから、これらのアセンブリ及びピニオ
ン５６と入力軸２５のアセンブリを下部ハウジング３０
に組付けて、次に下部ハウジング３０に上部ハウジング
３１を組付けることになる。自動車の組立の際、前輪ｌ
のアライメント及び後輪２のアライメントを設定するま
では、カム部材３日を第５図・第１０図の中立状態に保
持することが必要である．そこで、上記のように後輪操
舵装置２０のユニットを組立てたときに、第１５図に示
すように支軸３９の後端の立溝６６を上部ハウジング３
ｌの上下１対のマーク６７に合わせてカム部材３８を中
立状態に設定し、下部ハウジング３０のボス部３０ｂの
ボルト６８で人力軸２５を一時的に固定する。但し、自
動車の組立完了後、前輪１のアライメントと後輸２のア
ライメントの設定後、ボルト６８は取外される．前記カ
ム部材３８を支持する支軸３９の前端部に１対のスラス
ト軸受４３・４４が設けられ、支軸３９はこれらスラス
ト軸受４３・４４により軸方向に支持されているので、
出力軸３９の連結軸部３４がローラ枢支部３３Ｌ・３３
Ｒに対して前後に非対称である故に支軸３９に軸方向の
外力が作用しても支軸３９が軸方向に移動することはな
いし、支軸３９とハウジング２９間に大きな回転摺動抵
抗が生じることもない。但し、スラスト軸受４４は支軸
３９の後端部に設けてもよい。Next, the spur gear 55 and the bearings 40, 4l, 43, and 44 are assembled to the support shaft 39, and then these assemblies and the assembly of the pinion 56 and input shaft 25 are attached to the lower housing 30.
Then, the upper housing 31 is assembled to the lower housing 30. When assembling a car, the front wheels
It is necessary to maintain the cam member 3 in the neutral state shown in Figs. 5 and 10 until the alignment of the rear wheel 2 and rear wheel 2 are set. Therefore, when the unit of the rear wheel steering device 20 is assembled as described above, the vertical groove 66 at the rear end of the support shaft 39 is inserted into the upper housing 3 as shown in FIG.
The cam member 38 is set to a neutral state in alignment with the pair of upper and lower marks 67 of the lower housing 30, and the human power shaft 25 is temporarily fixed with the bolt 68 of the boss portion 30b of the lower housing 30. However, after the assembly of the automobile is completed and the alignment of the front wheels 1 and rear wheels 2 are set, the bolts 68 are removed. A pair of thrust bearings 43 and 44 are provided at the front end of the support shaft 39 that supports the cam member 38, and the support shaft 39 is supported in the axial direction by these thrust bearings 43 and 44.
The connecting shaft portion 34 of the output shaft 39 is connected to the roller pivot portions 33L and 33.
Since it is asymmetrical in the longitudinal direction with respect to R, even if an external force in the axial direction is applied to the support shaft 39, the support shaft 39 does not move in the axial direction, and there is a large rotational sliding resistance between the support shaft 39 and the housing 29. It never happens. However, the thrust bearing 44 may be provided at the rear end of the support shaft 39.

前記ハウジング２９について、下部ハウジング３０と上
部ハウジング３ｌの合せ面６０が既述のように鉛直面に
対して４５度傾いた前方上りの傾斜面に形成されている
ので、゜下部ハウジング３０と上部ハウジング３１とを
結合する結合強度面で有利になるし、ハウジング２９内
に諸部品を組込む際にも何ら支障は生じない。Regarding the housing 29, the mating surface 60 of the lower housing 30 and the upper housing 3l is formed into a forward upward slope inclined at 45 degrees with respect to the vertical plane as described above, so that the lower housing 30 and the upper housing This is advantageous in terms of the strength of the connection between the housing 29 and the housing 29, and there is no problem in assembling the various parts into the housing 29.

〔別実施例〕[Another example]

前記実施例の後輪操舵装置２０に代えて、第１６図・第
１７図に示すような後輪操舵装置２ＯＡを用いてもよい
。但し、前記後輪操舵装置２０と同一又は同様の部品に
は同一符号を付して説明を省略する。In place of the rear wheel steering device 20 of the embodiment described above, a rear wheel steering device 2OA as shown in FIGS. 16 and 17 may be used. However, parts that are the same as or similar to those of the rear wheel steering device 20 are given the same reference numerals and explanations will be omitted.

この後輪操舵装置２０Ａにおいては、人力軸２５の回転
を支軸３９に伝達する為にウォームギャ機構７０が設け
られている。In this rear wheel steering device 20A, a worm gear mechanism 70 is provided to transmit the rotation of the human power shaft 25 to the support shaft 39.

即ち、ハウジング３９内で支軸３９の前部にはウォーム
ホイール７１が固着され、ウォームホイール７１の下側
にはウォームホイール７ｌの下部に噛合する小径のウォ
ームギャ７２が左右方向に向けて配設され、ウォームギ
ャ７２の左端近傍部と右端部は軸受メタルを介して下部
ハウジング３０の枢支部７３・７４で支持され、ウォー
ムギャ７２の左端部には小径の傘歯車７４が固着され、
入力軸２５の後端部には傘歯車７５に噛合する傘歯車７
６が固着されている。このウォームギャ機構７０の減速
比は前記実施例の平歯車５５とビニオン５６とからなる
減速機構の減速比と同じに設定されている。That is, a worm wheel 71 is fixed to the front part of the support shaft 39 within the housing 39, and a small-diameter worm gear 72 that meshes with the lower part of the worm wheel 7l is disposed below the worm wheel 71 in the left-right direction. The vicinity of the left end and the right end of the worm gear 72 are supported by the pivot parts 73 and 74 of the lower housing 30 via bearing metal, and a small diameter bevel gear 74 is fixed to the left end of the worm gear 72.
A bevel gear 7 that meshes with a bevel gear 75 is provided at the rear end of the input shaft 25.
6 is fixed. The reduction ratio of this worm gear mechanism 70 is set to be the same as the reduction ratio of the reduction mechanism consisting of the spur gear 55 and the pinion 56 of the previous embodiment.

ステアリングハンドル１ｌが第１図の矢印Ｆ．方向へ操
舵されると、人力軸２５が矢印Ｆ．の方向へ回転し、カ
ム部材３８は第１７図にて矢印Ｆ，の方向つまり第１０
図の矢印Ｆ，の方向へ回転し、またステアリングハンド
ル１１が矢印Ｆ，と反対方向へ操舵されるとカム部材３
８は上記と反対方向へ回転する。The steering handle 1l is indicated by arrow F in FIG. When steered in the direction of arrow F. The cam member 38 rotates in the direction of arrow F in FIG.
When the steering wheel 11 is rotated in the direction of the arrow F in the figure and the steering handle 11 is steered in the opposite direction to the arrow F, the cam member 3
8 rotates in the opposite direction to the above.

従って、後輪２を操舵する作用については前記実施例の
後輪操舵装置２０と同様であり、その詳しい説明は省略
する。Therefore, the operation of steering the rear wheels 2 is similar to that of the rear wheel steering device 20 of the embodiment described above, and detailed explanation thereof will be omitted.

このウォームギャ機構７０の作用について説明すると、
自動車の走行時、特にコーナリング時などタイロンド２
８から出力軸２６及びローラ３７Ｌ・３７Ｒを介して大
きな，外力が作用し、カム部材３８に回転モーメントが
作用するが、その回転モーメントはウォームギャ機横７
０で遮断され入力軸２５へ伝達されないから、ステアリ
ングハンドル２の操舵が重くなるなどの支障は全く生じ
ない． 尚、前記出力軸やカム部材の形状・構造は一例を示すも
のにすぎず、本発明の思想を逸脱しない範囲で適宜の変
更を加え得ることは言うまでもない．The operation of this worm gear mechanism 70 will be explained as follows.
Tyrondo 2 when driving a car, especially when cornering
8, a large external force acts on the output shaft 26 and the rollers 37L and 37R, and a rotational moment acts on the cam member 38.
Since the signal is cut off at 0 and is not transmitted to the input shaft 25, no problems such as heavy steering of the steering wheel 2 occur. It should be noted that the shapes and structures of the output shaft and the cam member are merely examples, and it goes without saying that appropriate changes can be made without departing from the spirit of the present invention.

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

図面は本発明の実施例を示すもので、第１図は自動車の
４輪操舵装置の概略構成図、第２図は第１図■矢視図、
第３図は後輪操舵装置の斜視図、第４図は後輪操舵装置
の横断平面図、第５図は第４図Ｖ−ｖ線断面図、第６図
は第４図■−■線断面図、第７図は左側ローラ枢支部の
ローラ枢支構造の拡大断面図、第８図はラバープッシュ
の拡大断面図、第９図は第４図ＩＸ−ＩＸ線断面図、第
１０図はカム部材とローラとの作動説明図、第１１図は
後輪操舵特性図、第１２図〜第１４図は出力軸にカム部
材を組付けるときの各段階の説明図、第１５図は上部ハ
ウジングの後面に臨む支軸の端面図、第１６図は別実施
例に係る後輪操舵装置の横断平面図、第１７図は第１６
図のＸ■−Ｘ■線断面図である。 ｌ・・前輪、　２・・後輪、　　１０・・前輪操舵装置
、　２０・２ＯＡ・・後輪操舵装置、２３・・中間シャ
フト、　　２６・・出力軸、３７Ｌ・３７Ｒ・・ローラ
、　３８・・カム部材、３９・・支軸、　６１・・第１
カム面、６２・・第２カム面、　６３・・第３カム面。 特許出願人　　　マツダ株式会社 第 図 第１１図The drawings show an embodiment of the present invention, and FIG. 1 is a schematic configuration diagram of a four-wheel steering system for an automobile, FIG. 2 is a view in the direction of the arrow ■ in FIG.
Fig. 3 is a perspective view of the rear wheel steering device, Fig. 4 is a cross-sectional plan view of the rear wheel steering device, Fig. 5 is a sectional view taken along the line V-v in Fig. 4, and Fig. 6 is a cross-sectional view taken along the line ■-■ in Fig. 4. 7 is an enlarged sectional view of the roller pivot structure of the left roller pivot, FIG. 8 is an enlarged sectional view of the rubber pusher, FIG. 9 is a sectional view taken along line IX-IX in FIG. 4, and FIG. An explanatory diagram of the operation of the cam member and rollers, Fig. 11 is a rear wheel steering characteristic diagram, Figs. 12 to 14 are explanatory diagrams of each stage when assembling the cam member to the output shaft, and Fig. 15 is an illustration of the upper housing. An end view of the support shaft facing the rear surface, FIG. 16 is a cross-sectional plan view of a rear wheel steering device according to another embodiment, and FIG.
It is a sectional view taken along the line X■-X■ in the figure. l...Front wheel, 2...Rear wheel, 10...Front wheel steering device, 20.2OA...Rear wheel steering device, 23...Intermediate shaft, 26...Output shaft, 37L, 37R...Roller, 38... Cam member, 39...support shaft, 61...first
Cam surface, 62...second cam surface, 63...third cam surface. Patent applicant Mazda Motor Corporation Figure 11

Claims (1)

【特許請求の範囲】[Claims] （１）前輪の操舵に応じて後輪を操舵する４輪操舵装置
において、 左右の後輪をタイロッドを介して連結する１本の出力軸
と、 前輪の転舵角に応じて出力軸と交差する方向の支軸回り
に回動するカム部材と、 上記出力軸に設けられ、カム部材の外周面の左右両側部
に当接する左右１対の当接部材と、上記出力軸とカム部
材と当接部材を収容するハウジングと、 上記カム部材を支持する支軸とハウジング間に介装され
、ハウジングに対して支軸を軸方向に規制するスラスト
軸受とを備えたことを特徴とする車両の後輪操舵装置。(1) In a four-wheel steering system that steers the rear wheels according to the steering of the front wheels, there is one output shaft that connects the left and right rear wheels via a tie rod, and an output shaft that intersects with the output shaft according to the steering angle of the front wheels. a cam member that rotates around a support shaft in a direction in which A rear vehicle comprising: a housing that accommodates a contact member; and a thrust bearing that is interposed between a support shaft that supports the cam member and the housing and that regulates the support shaft in the axial direction with respect to the housing. Wheel steering device.