JPH08337179A

JPH08337179A - Hydraulic power steering device

Info

Publication number: JPH08337179A
Application number: JP17026395A
Authority: JP
Inventors: Yosuke Mori; 洋介森; Tetsuya Murakami; 哲也村上
Original assignee: Koyo Seiko Co Ltd
Current assignee: Koyo Seiko Co Ltd
Priority date: 1995-06-12
Filing date: 1995-06-12
Publication date: 1996-12-24
Anticipated expiration: 2019-09-08
Also published as: JP3563157B2

Abstract

PURPOSE: To prevent the defective operation and generation of the flowing noise due to deformation of a valve member by making the closing angle of a throttled part between a recessed part for feeding the pressurized oil belonging to a second set and a recessed part for communication, and between the recessed part for communication and a second recessed part for discharging the pressurized oil larger that of other throttled part belonging to a first set. CONSTITUTION: A recessed part 50c for communication is arranged on each side of a second recessed part 51c for discharging pressurized oil. One of the recessed part 50c for communication is adjacent to a first recessed part 51b for discharging pressurized oil to be connected to a tank 71, while the other is adjacent to a recessed part for feeding pressurized oil to be connected to a pump 70. The respective throttled parts between the recessed part 51a for feeding pressurized oil and the recessed part 50c for communication, and between the recessed part 50c for communication and the second recessed part 51c for discharging pressurized oil belong to the second set, and the closing angle of the throttled part belonging to the second set is larger than that of the other throttled part belonging to a first set. The defective operation and generation of the flowing noise due to the deformation of valve members 31, 32 can be prevented thereby.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、操舵抵抗ならびに車速
や操舵角等の運転条件に応じて操舵補助力を付与するこ
とのできる油圧パワーステアリング装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic power steering system capable of applying a steering assist force in accordance with operating conditions such as steering resistance and vehicle speed and steering angle.

【０００２】[0002]

【従来の技術】油圧アクチュエータと、この油圧アクチ
ュエータに作用する油圧を操舵抵抗に応じ制御する油圧
制御バルブとを備え、操舵抵抗が大きくなると油圧アク
チュエータに供給される油圧を大きくして操舵補助力を
付与する油圧パワーステアリング装置が従来より用いら
れている。2. Description of the Related Art A hydraulic actuator and a hydraulic control valve for controlling the hydraulic pressure acting on the hydraulic actuator according to the steering resistance are provided. When the steering resistance increases, the hydraulic pressure supplied to the hydraulic actuator is increased to increase the steering assist force. The hydraulic power steering device for giving is conventionally used.

【０００３】そのような油圧制御バルブとして、筒状の
第１バルブ部材と、この第１バルブ部材に操舵抵抗に応
じ相対回転可能に挿入される第２バルブ部材とを有し、
その第１バルブ部材の内周と第２バルブ部材の外周との
間に、両バルブ部材の相対回転角度に応じて流路面積が
変化する複数の絞り部が設けられ、各絞り部は、操舵方
向と操舵抵抗に応じた操舵補助力を付与できるように、
ポンプとタンクと操舵補助力発生用油圧アクチュエータ
とを接続する油路に配置されたロータリー式油圧制御バ
ルブが用いられている。As such a hydraulic control valve, there is provided a tubular first valve member and a second valve member which is inserted into the first valve member so as to be relatively rotatable in accordance with steering resistance.
Between the inner circumference of the first valve member and the outer circumference of the second valve member, a plurality of throttle portions whose flow passage area changes according to the relative rotation angle of both valve members are provided. To give steering assist force according to direction and steering resistance,
A rotary hydraulic control valve arranged in an oil passage that connects a pump, a tank, and a hydraulic actuator for generating steering assist force is used.

【０００４】そのような制御バルブを備えた油圧パワー
ステアリング装置において、低速走行時において操舵の
高応答性を満足させ、高速走行時において操舵の安定性
を満足させるため、前記両バルブ部材の間の各絞り部を
第１の組と第２の組とに組分けし、第２の組に属する絞
り部とタンクとの間の油路に、車速等の運転条件に応じ
て自身の絞り部の流路面積を変化させる可変絞り弁を設
けることが提案されている。In a hydraulic power steering system equipped with such a control valve, in order to satisfy a high steering responsiveness at a low speed traveling and a steering stability at a high speed traveling, a valve between the valve members is provided. Each throttle is divided into a first set and a second set, and an oil passage between the throttle and the tank belonging to the second set is provided with its own throttle depending on operating conditions such as vehicle speed. It has been proposed to provide a variable throttle valve that changes the flow passage area.

【０００５】図８は、従来の油圧パワーステアリング装
置の構成を示し、操舵補助力発生用油圧アクチュエータ
２０と油圧制御バルブとを備える。その制御バルブは、
筒状の第１バルブ部材３１と、この第１バルブ部材３１
に操舵抵抗に応じ相対回転可能に挿入される第２バルブ
部材３２とを有する。その第１バルブ部材３１の内周と
第２バルブ部材３２の外周との間に、両バルブ部材３
１、３２の相対回転角度に応じて流路面積が変化する複
数の絞り部Ａ、Ａ′、Ｂ、Ｂ′、Ｃ、Ｃ′、Ｄ、Ｄ′が
設けられている。各絞り部Ａ、Ａ′、Ｂ、Ｂ′、Ｃ、
Ｃ′、Ｄ、Ｄ′は、操舵方向と操舵抵抗に応じた操舵補
助力を付与できるように、ポンプ７０とタンク７１と油
圧アクチュエータ２０とを接続する油路２７に配置され
る。FIG. 8 shows the structure of a conventional hydraulic power steering system, which includes a steering assist force generating hydraulic actuator 20 and a hydraulic control valve. The control valve is
A cylindrical first valve member 31 and the first valve member 31
And a second valve member 32 inserted so as to be rotatable relative to the steering resistance. Between the inner circumference of the first valve member 31 and the outer circumference of the second valve member 32, both valve members 3
A plurality of throttle portions A, A ′, B, B ′, C, C ′, D, D ′ whose flow passage area changes according to the relative rotation angles of 1, 32 are provided. Each throttle part A, A ', B, B', C,
C ′, D, and D ′ are arranged in the oil passage 27 that connects the pump 70, the tank 71, and the hydraulic actuator 20 so that a steering assist force according to the steering direction and steering resistance can be applied.

【０００６】その第１バルブ部材３１の内周に８ケの凹
部が互いに周方向の間隔をおいて形成され、その第２バ
ルブ部材３２の外周に８ケの凹部が互いに周方向の間隔
をおいて形成され、その第１バルブ部材３１に形成され
た凹部の軸方向に沿う縁と第２バルブ部材３２に形成さ
れた凹部の軸方向に沿う縁（図において○および△で囲
む部分）との間が前記絞り部Ａ、Ａ′、Ｂ、Ｂ′、Ｃ、
Ｃ′、Ｄ、Ｄ′を構成する。Eight recesses are formed on the inner periphery of the first valve member 31 at circumferential intervals, and eight recesses are formed on the outer periphery of the second valve member 32 at circumferential intervals. The edge of the concave portion formed in the first valve member 31 along the axial direction and the edge of the concave portion formed in the second valve member 32 along the axial direction (the portion surrounded by ○ and Δ in the figure). Between the narrowed portions A, A ', B, B', C,
Configure C ', D, D'.

【０００７】それら凹部は、ポンプ７０に接続される４
ケの圧油供給用凹部５１ａと、タンク７１に接続される
２ケの第１圧油排出用凹部５１ｂと、運転条件に応じ自
身の絞り部の流路面積を変化させる可変絞り弁６０を介
してタンク７１に接続される２ケの第２圧油排出用凹部
５１ｃと、油圧アクチュエータ２０の右操舵補助力発生
用油室に接続される２ケの右操舵用凹部５０ａと、油圧
アクチュエータ２０の左操舵補助力発生用油室に接続さ
れる２ケの左操舵用凹部５０ｂと、４ケの連絡用凹部と
を構成する。These recesses are connected to the pump 70.
Via the first pressure oil supply concave portion 51a, the two first pressure oil discharge concave portions 51b connected to the tank 71, and the variable throttle valve 60 that changes the flow passage area of its own throttle portion according to operating conditions. Of the second pressure oil discharge recesses 51c connected to the tank 71, two right steering assist recesses 50a connected to the right steering assist force generating oil chamber of the hydraulic actuator 20, and the hydraulic actuator 20 of the hydraulic actuator 20. Two left steering recesses 50b connected to the left steering assist force generating oil chamber and four communication recesses are formed.

【０００８】その第１圧油排出用凹部５１ｂは右操舵用
凹部５０ａと左操舵用凹部５０ｂとの間に配置され、第
２圧油排出用凹部５１ｃは連絡用凹部５０ｃの間に配置
され、右操舵用凹部５０ａと連絡用凹部５０ｃとの間お
よび左操舵用凹部５０ｂと連絡用凹部５０ｃとの間に圧
油供給用凹部５１ａは配置される。The first pressure oil discharge recess 51b is disposed between the right steering recess 50a and the left steering recess 50b, and the second pressure oil discharge recess 51c is disposed between the connection recess 50c. The pressure oil supply recess 51a is arranged between the right steering recess 50a and the communication recess 50c and between the left steering recess 50b and the communication recess 50c.

【０００９】その左右操舵用凹部５０ａ、５０ｂと第１
圧油排出用凹部５１ｂとの間の絞り部Ｂ、Ｄおよび左右
操舵用凹部５０ａ、５０ｂと圧油供給用凹部５１ａとの
間の絞り部Ａ、Ｃは第１の組に属し、その連絡用凹部５
０ｃと第２圧油排出用凹部５１ｃとの間の絞り部Ｂ′、
Ｄ′および連絡用凹部５０ｃと圧油供給用凹部５１ａと
の間の絞り部Ａ′、Ｃ′は第２の組に属する。その第２
の組に属する絞り部Ａ′、Ｂ′、Ｃ′、Ｄ′の中の連絡
用凹部５０ｃと第２圧油排出用凹部５１ｃとの間の絞り
部Ｂ′、Ｄ′（図において△により囲まれた縁により構
成される）の閉鎖角度は、第１の組に属する絞り部Ａ、
Ｂ、Ｃ、Ｄの閉鎖角度よりも大きくされている。The left and right steering recesses 50a and 50b and the first
The throttles B and D between the pressure oil discharge recesses 51b and the throttles A and C between the left and right steering recesses 50a and 50b and the pressure oil supply recesses 51a belong to the first group, and are for communication thereof. Recess 5
0c and the second pressure oil discharge recess 51c, a throttle portion B ',
D'and the throttles A'and C'between the communication recess 50c and the pressure oil supply recess 51a belong to the second group. The second
Of the throttling portions A ', B', C ', D'belonging to the set, the throttling portions B', D '(enclosed by .DELTA. In the figure) between the communicating recess 50c and the second pressure oil discharging recess 51c. Closed angle), which is defined by
It is made larger than the closing angles of B, C, and D.

【００１０】なお、本件明細書において「閉鎖角度」と
は、操舵抵抗のない状態にある絞り部を全閉するのに要
する両バルブ部材の相対回転角度をいう。なお実際の絞
り部は、最も絞った状態において全閉となる必要はな
く、機能上差し支えのない範囲で流路面積を有していて
もよい。In the present specification, the "closed angle" means the relative rotation angle of both valve members required to fully close the throttle portion in the state where there is no steering resistance. The actual throttle portion does not need to be fully closed in the most throttled state, and may have a flow passage area within a range where there is no functional problem.

【００１１】図８は、右方へ操舵することによって生じ
る操舵抵抗により両バルブ部材３１、３２が相対回転し
た状態を示し、その相対回転により上記絞り部Ａ、Ａ′
の流路面積が大きくなり、絞り部Ｂ、Ｂ′の流路面積が
小さくなり、絞り部Ｃ、Ｃ′の流路面積が小さくなり、
絞り部Ｄ、Ｄ′の流路面積が大きくなる。これにより、
図中矢印で示す圧油の流れにより油圧シリンダ２０の右
操舵補助力発生用油室２２に操舵方向と操舵抵抗に応じ
た圧力の圧油が供給され、また、左操舵補助力発生用油
室２３からタンク７１に油が還流し、車両の右方への操
舵補助力が油圧シリンダ２０からラック１６に作用す
る。左方へ操舵した場合、絞り部Ａ、Ａ′、Ｂ、Ｂ′、
Ｃ、Ｃ′、Ｄ、Ｄ′の開度は右方へ操舵した場合と逆に
なり、車両の左方への操舵補助力が油圧シリンダ２０か
らラック１６に作用する。FIG. 8 shows a state in which both valve members 31, 32 relatively rotate due to steering resistance generated by steering to the right, and the relative rotation causes the throttle parts A, A '.
, The flow passage area of the throttle portions B and B ′ becomes smaller, and the flow passage area of the throttle portions C and C ′ becomes smaller,
The flow passage area of the throttle portions D and D'becomes larger. This allows
Due to the flow of pressure oil shown by the arrow in the figure, pressure oil having a pressure according to the steering direction and steering resistance is supplied to the right steering assist force generating oil chamber 22 of the hydraulic cylinder 20, and the left steering assist force generating oil chamber is also supplied. Oil flows from 23 to the tank 71, and steering assist force to the right of the vehicle acts on the rack 16 from the hydraulic cylinder 20. When steered to the left, the throttles A, A ', B, B',
The opening degrees of C, C ′, D, and D ′ are opposite to those when steering to the right, and the steering assist force to the left of the vehicle acts on the rack 16 from the hydraulic cylinder 20.

【００１２】上記従来例の構成によれば、図９に示す油
圧回路が構成される。その可変絞り弁６０の自身の絞り
部の開度は、高速になると大きくなり、低速になると小
さくなるものとされている。これにより、低速走行時や
据え切り時にあっては可変絞り弁６０の絞り部の流路面
積は全閉とされ、第１の組に属する絞り部Ａ、Ｂ、Ｃ、
Ｄの流路面積変化のみに応じて油圧アクチュエータ２０
に作用する油圧を制御するので、図１０において一点鎖
線で示すように、操舵入力トルクが小さく両バルブ部材
の相対回転角度が小さくても、絞り部Ａ、Ｂ、Ｃ、Ｄの
流路面積が小さくなる。よって、操舵補助力を発生させ
るための油圧の増加割合が大きくなり、操舵の高応答性
を満足させることができる。一方、高速走行時にあって
は、可変絞り弁６０の絞り部の流路面積は最大とされ、
第１の組に属する絞り部Ａ、Ｂ、Ｃ、Ｄの流路面積変化
と第２の組に属する絞り部Ａ′、Ｂ′、Ｃ′、Ｄ′の流
路面積変化の両方に応じて油圧アクチュエータ２０に作
用する油圧を制御するので、操舵入力トルクを大きくし
て両バルブ部材の相対回転角を大きくしない限り、絞り
部Ａ′、Ｂ′、Ｃ′、Ｄ′の流路面積は小さくなること
はない。よって、操舵補助力を発生させる油圧の増加割
合は小さく、操舵の安定性を満足させることができる。According to the configuration of the above-mentioned conventional example, the hydraulic circuit shown in FIG. 9 is constructed. The opening degree of the throttle portion of the variable throttle valve 60 itself is set to increase at high speed and decrease at low speed. As a result, the flow passage area of the throttle portion of the variable throttle valve 60 is fully closed during low-speed traveling or stationary operation, and the throttle portions A, B, C belonging to the first group,
The hydraulic actuator 20 according to only the change of the flow passage area of D
Since the hydraulic pressure acting on the valve is controlled, as shown by the chain line in FIG. Get smaller. Therefore, the rate of increase of the hydraulic pressure for generating the steering assist force becomes large, and the high responsiveness of steering can be satisfied. On the other hand, when traveling at high speed, the flow passage area of the throttle portion of the variable throttle valve 60 is maximized,
Depending on both the flow passage area changes of the throttle portions A, B, C, D belonging to the first set and the flow passage area changes of the throttle portions A ′, B ′, C ′, D ′ belonging to the second set. Since the hydraulic pressure acting on the hydraulic actuator 20 is controlled, the flow passage area of the throttle portions A ', B', C ', D'is small unless the steering input torque is increased to increase the relative rotation angle of both valve members. It never happens. Therefore, the increase rate of the hydraulic pressure that generates the steering assist force is small, and the steering stability can be satisfied.

【００１３】[0013]

【発明が解決しようとする課題】しかし、上記従来の構
成では、可変絞り弁６０の絞り部の流路面積が全閉とな
る低速走行時や据え切り時において、第２の組に属する
絞り部Ａ′、Ｂ′、Ｃ′、Ｄ′で圧油の流動はなく、第
１の組に属する絞り部Ａ、Ｂ、Ｃ、Ｄでの圧油の流動に
よってのみ操舵補助力が制御される。そのため、例えば
図８に示す右方への操舵状態においては、第１の組に属
する絞り部Ａを構成する圧油供給用凹部５１ａと右操舵
用凹部５０ａとにおける油圧が、第２の組に属する絞り
部Ａ′を構成する圧油供給用凹部５１ａと連絡用凹部５
０ｃとにおける油圧よりも大きくなり、両バルブ部材３
１、３２に油圧が対向２位置のみから作用することにな
る。そのため、両バルブ部材３１、３２の横断面が楕円
形状に変形し、第１バルブ部材３１の内周面と第２バル
ブ部材３２の外周面との間の摩擦力が大きくなり、作動
不良を生じるという問題がある。さらに、低速走行時や
据え切り時においては、第１の組に属する絞り部Ａ、
Ｂ、Ｃ、Ｄにおいてのみ圧油が流動するため、その絞り
部Ａ、Ｂ、Ｃ、Ｄを通過する圧油流量が多くなり、大き
な流動音が発生するという問題がある。However, in the above-described conventional configuration, the throttle portions belonging to the second set are operated at low speed running or stationary steering when the flow passage area of the throttle portion of the variable throttle valve 60 is fully closed. There is no pressure oil flow in A ′, B ′, C ′, D ′, and the steering assist force is controlled only by the pressure oil flow in the throttle portions A, B, C, D belonging to the first set. Therefore, for example, in the rightward steering state shown in FIG. 8, the hydraulic pressures in the pressure oil supply concave portion 51a and the right steering concave portion 50a that form the throttle portion A belonging to the first group are set to the second group. Pressure oil supply recessed portion 51a and communication recessed portion 5 which constitute the throttle portion A'belonging to
It becomes larger than the hydraulic pressure at 0c, and both valve members 3
The hydraulic pressure acts on 1 and 32 only from two opposing positions. Therefore, the cross sections of both the valve members 31 and 32 are deformed into an elliptical shape, and the frictional force between the inner peripheral surface of the first valve member 31 and the outer peripheral surface of the second valve member 32 increases, resulting in malfunction. There is a problem. Furthermore, when traveling at low speed or stationary, the throttle unit A belonging to the first group,
Since the pressure oil flows only in B, C, and D, there is a problem that the flow rate of the pressure oil passing through the throttle portions A, B, C, and D increases and a large flowing noise is generated.

【００１４】そこで、絞り部Ａ、Ａ′、Ｂ、Ｂ′、Ｃ、
Ｃ′、Ｄ、Ｄ′の数を増加させ、両バルブ部材３１、３
２に対する油圧の作用位置を増加させることが考えられ
る。しかし、上記従来の両バルブ部材３１、３２におけ
る凹部の配置では、低速走行時や据え切り時に油圧の作
用位置を３位置とするには、各バルブ部材３１、３２そ
れぞれに形成する凹部の数を１２ケとする必要があり、
４位置とするには１６ケの凹部を形成する必要がある。
すなわち、油圧の作用位置の数に比例して凹部の数を増
加させる必要がある。そのため、加工コストが増大し、
また、バルブ部材の径を大きくする必要があるため装置
が大型化するという問題がある。Therefore, the narrowed portions A, A ', B, B', C,
By increasing the number of C ', D, D', both valve members 31, 3
It is conceivable to increase the operating position of the hydraulic pressure with respect to 2. However, in the conventional arrangement of the recesses in both the valve members 31 and 32, the number of recesses formed in each of the valve members 31 and 32 must be set in order to set the hydraulic action position to three positions during low speed traveling or stationary steering. It is necessary to make 12
It is necessary to form 16 recesses in order to obtain 4 positions.
That is, it is necessary to increase the number of recesses in proportion to the number of hydraulic pressure application positions. Therefore, the processing cost increases,
In addition, there is a problem that the device becomes large because it is necessary to increase the diameter of the valve member.

【００１５】本発明は、上記課題を解決することのでき
る油圧パワーステアリング装置を提供することを目的と
する。It is an object of the present invention to provide a hydraulic power steering system that can solve the above problems.

【００１６】[0016]

【課題を解決するための手段】本発明は、操舵補助力発
生用油圧アクチュエータと、油圧制御バルブとを備え、
その油圧制御バルブは、筒状の第１バルブ部材と、この
第１バルブ部材に操舵抵抗に応じ相対回転可能に挿入さ
れる第２バルブ部材とを有し、両バルブ部材の間は、そ
の操舵補助力発生用油圧アクチュエータをポンプとタン
クとに接続する油路とされ、その第１バルブ部材の内周
に複数の凹部が互いに周方向の間隔をおいて形成され、
その第２バルブ部材の外周に複数の凹部が互いに周方向
の間隔をおいて形成され、その第１バルブ部材に形成さ
れた凹部の間に第２バルブ部材に形成された凹部が位置
し、それら凹部は、ポンプに接続される複数の圧油供給
用凹部と、タンクに接続される複数の第１圧油排出用凹
部と、運転条件に応じ自身の絞り部の流路面積を変化さ
せる可変絞り弁を介してタンクに接続される複数の第２
圧油排出用凹部と、油圧アクチュエータの右操舵補助力
発生用油室に接続される複数の右操舵用凹部と、油圧ア
クチュエータの左操舵補助力発生用油室に接続される複
数の左操舵用凹部と、複数の連絡用凹部とを構成し、そ
の第１バルブ部材に形成された凹部の軸方向に沿う縁と
第２バルブ部材に形成された凹部の軸方向に沿う縁との
間が絞り部を構成し、各絞り部は、操舵方向と操舵抵抗
に応じた両バルブ部材の相対回転により操舵補助力を付
与できるように前記油路に配置される油圧パワーステア
リング装置に適用される。The present invention comprises a hydraulic actuator for generating a steering assist force and a hydraulic control valve,
The hydraulic control valve has a tubular first valve member and a second valve member that is inserted into the first valve member so as to be rotatable relative to the first valve member. An oil passage connecting the auxiliary force generating hydraulic actuator to the pump and the tank is formed, and a plurality of recesses are formed in the inner periphery of the first valve member at circumferential intervals.
A plurality of recesses are formed on the outer circumference of the second valve member at circumferential intervals, and the recesses formed in the second valve member are located between the recesses formed in the first valve member. The recesses are a plurality of pressure oil supply recesses connected to the pump, a plurality of first pressure oil discharge recesses connected to the tank, and a variable throttle that changes the flow passage area of its own throttle portion according to operating conditions. A plurality of second valves connected to the tank via valves
Pressure oil discharge recess, multiple right steering recesses connected to the hydraulic actuator right steering assist force generating oil chamber, and multiple left steering steering recesses connected to the hydraulic actuator left steering assist force generating oil chamber A concave portion and a plurality of connecting concave portions are formed, and a space between an edge of the concave portion formed in the first valve member along the axial direction and an edge of the concave portion formed in the second valve member along the axial direction is reduced. Each throttle portion is applied to a hydraulic power steering device arranged in the oil passage so that a steering assist force can be applied by relative rotation of both valve members according to the steering direction and steering resistance.

【００１７】本件発明は、その油圧パワーステアリング
装置において、各第２圧油排出用凹部の両隣に連絡用凹
部が配置され、各第２圧油排出用凹部の両隣の連絡用凹
部の一方は第１圧油排出用凹部に隣接すると共に他方は
圧油供給用凹部に隣接し、圧油供給用凹部と連絡用凹部
との間の絞り部と、圧油供給用凹部に隣接する連絡用凹
部と第２圧油排出用凹部との間の絞り部とは第２の組に
属し、他の絞り部は第１の組に属し、第２の組に属する
絞り部の閉鎖角度は第１の組に属する絞り部の閉鎖角度
よりも大きくされていることを特徴とする。According to the present invention, in the hydraulic power steering device, the connection recesses are arranged on both sides of each second pressure oil discharge recess, and one of the connection recesses on both sides of each second pressure oil discharge recess is the first. 1 Adjacent to the pressure oil discharge recess and the other adjacent to the pressure oil supply recess, a narrowed portion between the pressure oil supply recess and the communication recess, and a communication recess adjacent to the pressure oil supply recess The throttle portion between the second pressure oil discharge concave portion belongs to the second group, the other throttle portions belong to the first group, and the closing angle of the throttle section belonging to the second group is the first group. It is characterized in that it is made larger than the closing angle of the narrowed portion belonging to.

【００１８】本件発明の油圧パワーステアリング装置に
おいて、その第１バルブ部材の内周に形成される凹部は
１０ケとされ、その第２バルブ部材の外周に形成される
凹部は１０ケとされ、それら凹部は、ポンプに接続され
る４ケの圧油供給用凹部と、タンクに接続される４ケの
第１圧油排出用凹部と、運転条件に応じ自身の絞り部の
流路面積を変化させる可変絞り弁を介してタンクに接続
される２ケの第２圧油排出用凹部と、油圧アクチュエー
タの右操舵補助力発生用油室に接続される３ケの右操舵
用凹部と、油圧アクチュエータの左操舵補助力発生用油
室に接続される３ケの左操舵用凹部と、４ケの連絡用凹
部とを構成し、各第２圧油排出用凹部の両隣に連絡用凹
部が配置され、各第２圧油排出用凹部の両隣の連絡用凹
部の一方は第１圧油排出用凹部に隣接すると共に他方は
圧油供給用凹部に隣接し、一方の第２圧油排出用凹部の
両隣の各連絡用凹部に隣接する第１圧油排出用凹部と圧
油供給用凹部とは右操舵用凹部に隣接し、他方の第２圧
油排出用凹部の両隣の各連絡用凹部に隣接する第１圧油
排出用凹部と圧油供給用凹部とは左操舵用凹部に隣接
し、その各第１圧油排出用凹部に隣接する左右操舵用凹
部は圧油供給用凹部の両隣に配置され、その圧油供給用
凹部に隣接する右操舵用凹部は左操舵用凹部に隣接する
第１圧油排出用凹部に隣接し、その圧油供給用凹部に隣
接する左操舵用凹部は右操舵用凹部に隣接する第１圧油
排出用凹部に隣接するのが好ましい。In the hydraulic power steering system of the present invention, the first valve member has 10 recesses formed on the inner circumference thereof, and the second valve member has 10 recesses formed on the outer circumference thereof. The concave portion changes the flow passage area of its own throttle portion according to the operating conditions, four pressure oil supplying concave portions connected to the pump, four first pressure oil discharging concave portions connected to the tank. Two second pressure oil discharge recesses connected to the tank via the variable throttle valve, three right steering recesses connected to the right steering assist force generating oil chamber of the hydraulic actuator, and the hydraulic actuator 3 left steering recesses connected to the left steering assist force generating oil chamber and 4 connecting recesses are formed, and the connecting recesses are arranged on both sides of each of the second pressure oil discharge recesses, One of the communication recesses on both sides of each second pressure oil discharge recess is the first pressure A first pressure oil discharge recess and a pressure oil supply recess adjacent to the discharge recess and the other adjacent to the pressure oil supply recess and adjacent to each of the communication recesses on both sides of one of the second pressure oil discharge recesses. Is adjacent to the right steering recess, and is adjacent to the other connecting recesses on both sides of the other second pressure oil exhaust recess. The first pressure oil exhaust recess and the pressure oil supply recess are adjacent to the left steering recess. The left and right steering recesses adjacent to the first pressure oil discharge recesses are arranged on both sides of the pressure oil supply recess, and the right steering recess adjacent to the pressure oil supply recess is adjacent to the left steering recess. It is preferable that the left steering recess adjacent to the first pressure oil discharge recess and adjacent to the pressure oil supply recess be adjacent to the first pressure oil discharge recess adjacent to the right steering recess.

【００１９】また、本発明の油圧パワーステアリング装
置において、その第１バルブ部材の内周に形成される凹
部は１２ケとされ、その第２バルブ部材の外周に形成さ
れる凹部は１２ケとされ、それら凹部は、ポンプに接続
される４ケの圧油供給用凹部と、タンクに接続される４
ケの第１圧油排出用凹部と、運転条件に応じ自身の絞り
部の流路面積を変化させる可変絞り弁を介してタンクに
接続される４ケの第２圧油排出用凹部と、油圧アクチュ
エータの右操舵補助力発生用油室に接続される２ケの右
操舵用凹部と、油圧アクチュエータの左操舵補助力発生
用油室に接続される２ケの左操舵用凹部と、８ケの連絡
用凹部とを構成し、各第２圧油排出用凹部の両隣に連絡
用凹部が配置され、各第２圧油排出用凹部の両隣の連絡
用凹部の一方は第１圧油排出用凹部に隣接すると共に他
方は圧油供給用凹部に隣接し、各連絡用凹部に隣接する
圧油供給用凹部は第１圧油排出用凹部の両隣の左右圧油
供給用凹部に隣接するのが好ましい。Further, in the hydraulic power steering apparatus of the present invention, the first valve member has 12 recesses formed on the inner circumference thereof, and the second valve member has 12 recesses formed on the outer circumference thereof. , The four recesses are connected to the pump, and the four recesses for supplying pressure oil are connected to the tank.
First pressure oil discharge recesses, four second pressure oil discharge recesses connected to the tank via a variable throttle valve that changes the flow passage area of the throttle unit according to operating conditions, and hydraulic pressure. Two right steering recesses connected to the right steering assist force generating oil chamber of the actuator, two left steering recesses connected to the left steering assist force generating oil chamber of the hydraulic actuator, and eight The connecting recesses are formed on both sides of each of the second pressure oil discharging recesses, and one of the connecting recesses on both sides of each of the second pressure oil discharging recesses is the first pressure oil discharging recess. And the other is adjacent to the pressure oil supply recess, and the pressure oil supply recesses adjacent to the respective communication recesses are preferably adjacent to the left and right pressure oil supply recesses on both sides of the first pressure oil discharge recess. .

【００２０】[0020]

【作用】本発明の油圧パワーステアリング装置によれ
ば、第２の組に属する絞り部は、圧油供給用凹部と連絡
用凹部との間、および、圧油供給用凹部に隣接する連絡
用凹部と第２圧油排出用凹部との間に位置し、各第２圧
油排出用凹部の両隣に連絡用凹部が配置され、各第２圧
油排出用凹部の両隣の連絡用凹部の一方は第１圧油排出
用凹部に隣接すると共に他方は圧油供給用凹部に隣接す
る。よって、低速走行時や据え切り時に可変絞り弁の自
身の絞り部を全閉としても、第２の組に属する絞り部に
おいて圧油を流動させることができる。しかも、その可
変絞り弁の自身の絞り部を全閉とした場合、第２の組に
属する絞り部において流動する圧油は、第２圧油排出用
凹部と一方の連絡用凹部との間の第１の組に属する絞り
部、および、その一方の連絡用凹部と第１圧油排出用凹
部との間の第１の組に属する絞り部を介して第１圧油排
出用凹部に至るので、第１の組に属する絞り部の流路面
積変化のみに応じて油圧シリンダ２０に作用する油圧を
制御できる。これにより、低速走行時や据え切り時にお
ける各バルブ部材に対する油圧の作用位置を増加させる
ために、各バルブ部材に形成する凹部の数を、従来より
も少なくすることができる。例えば、その低速走行時や
据え切り時における油圧の作用位置を４位置とするの
に、従来であれば各バルブ部材それぞれに形成する凹部
の数を１６ケとする必要があったのに対し、請求項２に
記載の構成によれば１０ケでよく、請求項３に記載の構
成によれば１２ケでよい。According to the hydraulic power steering apparatus of the present invention, the throttle portion belonging to the second group is provided between the pressure oil supply recess and the connection recess and between the connection recess adjacent to the pressure oil supply recess. Between the second pressure oil discharge recesses, the communication recesses are arranged on both sides of each second pressure oil discharge recess, and one of the communication recesses on both sides of each second pressure oil discharge recess is It is adjacent to the first pressure oil discharge recess and the other is adjacent to the pressure oil supply recess. Therefore, even when the throttle portion of the variable throttle valve is fully closed during low-speed traveling or stationary operation, the pressure oil can be made to flow in the throttle portion belonging to the second group. Moreover, when the throttle portion of the variable throttle valve itself is fully closed, the pressure oil flowing in the throttle portion belonging to the second set is between the second pressure oil discharge concave portion and the one communication concave portion. Since the throttle portion belonging to the first group and the throttle portion belonging to the first group between one of the connecting concave portion and the first pressure oil discharging concave portion reach the first pressure oil discharging concave portion. , The hydraulic pressure acting on the hydraulic cylinder 20 can be controlled only in accordance with the change in the flow passage area of the throttle portion belonging to the first group. As a result, the number of recesses formed in each valve member can be made smaller than in the conventional case in order to increase the position where hydraulic pressure acts on each valve member during low speed traveling or stationary steering. For example, in order to set the hydraulic pressure application position at four positions during low speed running or stationary steering, it is necessary to set the number of recesses formed in each valve member to 16 in the related art. According to the configuration described in claim 2, 10 pieces may be used, and according to the configuration described in claim 3, 12 pieces may be used.

【００２１】[0021]

【第１実施例】以下、図１〜図５を参照して第１実施例
を説明する。[First Embodiment] A first embodiment will be described below with reference to FIGS.

【００２２】図１に示すラックピニオン式油圧パワース
テアリング装置１は、車両のハンドル（図示省略）に連
結される入力軸２と、この入力軸２にトーションバー６
を介し連結される出力軸３を備えている。そのトーショ
ンバー６は、ピン４により入力軸２に連結され、セレー
ション５により出力軸３に連結されている。その入力軸
２は、ベアリング８を介しバルブハウジング７により支
持され、また、ベアリング１２を介し出力軸３により支
持されている。その出力軸３はベアリング１０、１１を
介しラックハウジング９により支持されている。その出
力軸３にピニオン１５が形成され、このピニオン１５に
噛み合うラック１６に操舵用車輪（図示省略）が連結さ
れる。これにより、操舵による入力軸２の回転は、トー
ションバー６を介してピニオン１５に伝達され、このピ
ニオン１５の回転によりラック１６は車両幅方向に移動
し、このラック１６の移動により車両の操舵がなされ
る。なお、入出力軸２、３とハウジング７との間にはオ
イルシール４２、４３が介在する。また、ラック１６を
支持するサポートヨーク４０がバネ４１の弾性力により
ラック１６に押し付けられている。A rack and pinion type hydraulic power steering system 1 shown in FIG. 1 has an input shaft 2 connected to a steering wheel (not shown) of a vehicle, and a torsion bar 6 on the input shaft 2.
The output shaft 3 is connected via. The torsion bar 6 is connected to the input shaft 2 by the pin 4 and is connected to the output shaft 3 by the serration 5. The input shaft 2 is supported by the valve housing 7 via a bearing 8 and is supported by the output shaft 3 via a bearing 12. The output shaft 3 is supported by a rack housing 9 via bearings 10 and 11. A pinion 15 is formed on the output shaft 3, and a steering wheel (not shown) is connected to a rack 16 that meshes with the pinion 15. As a result, the rotation of the input shaft 2 due to steering is transmitted to the pinion 15 via the torsion bar 6, the rotation of the pinion 15 moves the rack 16 in the vehicle width direction, and the movement of the rack 16 causes steering of the vehicle. Done. Oil seals 42 and 43 are interposed between the input / output shafts 2 and 3 and the housing 7. The support yoke 40 that supports the rack 16 is pressed against the rack 16 by the elastic force of the spring 41.

【００２３】操舵補助力発生用油圧アクチュエータとし
て油圧シリンダ２０が設けられている。この油圧シリン
ダ２０は、ラックハウジング９により構成されるシリン
ダチューブと、ラック１６に一体化されるピストン２１
を備えている。そのピストン２１により仕切られる油室
２２、２３に操舵方向と操舵抵抗に応じて圧油を供給す
るため、ロータリー式油圧制御バルブ３０が設けられて
いる。A hydraulic cylinder 20 is provided as a hydraulic actuator for generating a steering assist force. The hydraulic cylinder 20 includes a cylinder tube formed by the rack housing 9 and a piston 21 integrated with the rack 16.
It has. A rotary hydraulic control valve 30 is provided in order to supply pressure oil to the oil chambers 22 and 23 partitioned by the piston 21 according to the steering direction and steering resistance.

【００２４】その制御バルブ３０は、バルブハウジング
７に相対回転可能に挿入されている筒状の第１バルブ部
材３１と、この第１バルブ部材３１に同軸中心に相対回
転可能に挿入されている第２バルブ部材３２とを備えて
いる。その第１バルブ部材３１は出力軸３にピン２９に
より同行回転するよう連結されている。その第２バルブ
部材３２は入力軸２と一体的に成形され、すなわち入力
軸２の外周部により第２バルブ部材３２が構成され、第
２バルブ部材３２は入力軸２と同行回転する。よって、
第１バルブ部材３１と第２バルブ部材３２は、操舵抵抗
に応じ前記トーションバー６がねじれることで同軸中心
に相対回転する。The control valve 30 has a cylindrical first valve member 31 inserted into the valve housing 7 so as to be rotatable relative to it, and a first valve member 31 inserted into the first valve member 31 to be rotatable relative to the coaxial center. Two valve members 32 are provided. The first valve member 31 is connected to the output shaft 3 by a pin 29 so as to rotate together. The second valve member 32 is formed integrally with the input shaft 2, that is, the outer peripheral portion of the input shaft 2 constitutes the second valve member 32, and the second valve member 32 rotates together with the input shaft 2. Therefore,
The first valve member 31 and the second valve member 32 relatively rotate about the same axis as the torsion bar 6 is twisted according to the steering resistance.

【００２５】そのバルブハウジング７に、ポンプ７０に
接続される入口ポート３４と、前記油圧シリンダ２０の
一方の油室２２に接続される第１ポート３７と、他方の
油室２３に接続される第２ポート３８と、直接にタンク
７１に接続される第１出口ポート３６と、後述の可変絞
り弁６０を介しタンク７１に接続される第２出口ポート
６１とが設けられている。各ポート３４、３６、３７、
３８、６１は、その第１バルブ部材３１と第２バルブ部
材３２との内外周間の弁間流路２７を介し互いに接続さ
れている。The valve housing 7 has an inlet port 34 connected to the pump 70, a first port 37 connected to one oil chamber 22 of the hydraulic cylinder 20, and a first port 37 connected to the other oil chamber 23. Two ports 38, a first outlet port 36 directly connected to the tank 71, and a second outlet port 61 connected to the tank 71 via a variable throttle valve 60 described later are provided. Each port 34, 36, 37,
38 and 61 are connected to each other through an intervalve flow path 27 between the inner and outer circumferences of the first valve member 31 and the second valve member 32.

【００２６】すなわち、図２、図３に示すように、第１
バルブ部材３１の内周に１０ケの凹部５０ａ、５０ｂ、
５０ｃが周方向に関し互いに等間隔に形成され、第２バ
ルブ部材３２の外周に１０ケの凹部５１ａ、５１ｂ、５
１ｃが周方向に関し互いに等間隔に形成されている。図
４は実線により第２バルブ部材３２の展開図を示し、鎖
線により第１バルブ部材３１に形成された凹部５０ａ、
５０ｂ、５０ｃを示す。第１バルブ部材３１に形成され
た凹部５０ａ、５０ｂ、５０ｃの間に第２バルブ部材３
２に形成された凹部５１ａ、５１ｂ、５１ｃが位置す
る。That is, as shown in FIGS. 2 and 3, the first
Ten recesses 50a, 50b on the inner circumference of the valve member 31,
50 c are formed at equal intervals in the circumferential direction, and 10 recesses 51 a, 51 b, 5 are formed on the outer periphery of the second valve member 32.
1c are formed at equal intervals in the circumferential direction. FIG. 4 shows a development view of the second valve member 32 by a solid line, and a recess 50a formed in the first valve member 31 by a chain line.
50b and 50c are shown. The second valve member 3 is provided between the recesses 50a, 50b, 50c formed in the first valve member 31.
The concave portions 51a, 51b, 51c formed on the second side are located.

【００２７】その第１バルブ部材３１に形成された凹部
は、３ケの右操舵用凹部５０ａと、３ケの左操舵用凹部
５０ｂと、４ケの連絡用凹部５０ｃとを構成する。各右
操舵用凹部５０ａは、前記第１ポート３７を介して油圧
シリンダ２０の右操舵補助力発生用油室２２に接続され
る。各左操舵用凹部５０ｂは前記第２ポート３８を介し
て油圧シリンダ２０の左操舵補助力発生用油室２３に接
続される。The recesses formed in the first valve member 31 form three right steering recesses 50a, three left steering recesses 50b, and four connecting recesses 50c. Each right steering recess 50 a is connected to the right steering assist force generating oil chamber 22 of the hydraulic cylinder 20 via the first port 37. Each left steering recess 50b is connected to the left steering assist force generating oil chamber 23 of the hydraulic cylinder 20 via the second port 38.

【００２８】その第２バルブ部材３２に形成された凹部
は、４ケの圧油供給用凹部５１ａと、４ケの第１圧油排
出用凹部５１ｂと、２ケの第２圧油排出用凹部５１ｃと
を構成する。各圧油供給用凹部５１ａは、前記入口ポー
ト３４を介してポンプ７０に接続される。各第１圧油排
出用凹部５１ｂは、入力軸２に形成された流路５２ａか
ら入力軸２とトーションバー６との間を通り、入力軸２
に形成された流路５２ｂ（図１参照）と第１出口ポート
３６とを介しタンク７１に接続される。各第２圧油排出
用凹部５１ｃは、前記第２出口ポート６１を介して可変
絞り弁６０に接続される。The recesses formed in the second valve member 32 include four pressure oil supply recesses 51a, four first pressure oil discharge recesses 51b, and two second pressure oil discharge recesses. 51c. Each pressure oil supply recess 51 a is connected to the pump 70 via the inlet port 34. Each of the first pressure oil discharge recesses 51b passes from the flow path 52a formed in the input shaft 2 between the input shaft 2 and the torsion bar 6, and the input shaft 2
It is connected to the tank 71 through the flow path 52b (see FIG. 1) formed in the first outlet port 36. Each of the second pressure oil discharge recesses 51c is connected to the variable throttle valve 60 via the second outlet port 61.

【００２９】各第２圧油排出用凹部５１ｃの両隣に連絡
用凹部５０ｃが配置され、各第２圧油排出用凹部５１ｃ
の両隣の連絡用凹部５０ｃの一方は第１圧油排出用凹部
５１ｂに隣接すると共に他方は圧油供給用凹部５１ａに
隣接し、一方の第２圧油排出用凹部５１ｃの両隣の各連
絡用凹部５０ｃに隣接する第１圧油排出用凹部５１ｂと
圧油供給用凹部５１ａとは右操舵用凹部５０ａに隣接
し、他方の第２圧油排出用凹部５１ｃの両隣の各連絡用
凹部５０ｃに隣接する第１圧油排出用凹部５１ｂと圧油
供給用凹部５１ａとは左操舵用凹部５０ｂに隣接し、そ
の各第１圧油排出用凹部５１ｂに隣接する左右操舵用凹
部５０ａ、５０ｂは圧油供給用凹部５１ａの両隣に配置
され、その圧油供給用凹部５１ａに隣接する右操舵用凹
部５０ａは左操舵用凹部５０ｂに隣接する第１圧油排出
用凹部５１ｂに隣接し、その圧油供給用凹部５１ａに隣
接する左操舵用凹部５０ｂは右操舵用凹部５０ａに隣接
する第１圧油排出用凹部５１ｂに隣接する。Communication recesses 50c are arranged on both sides of each second pressure oil discharge recess 51c, and each second pressure oil discharge recess 51c.
One of the two communication recesses 50c adjacent to each other is adjacent to the first pressure oil discharge recess 51b and the other is adjacent to the pressure oil supply recess 51a. The first pressure oil discharge concave portion 51b and the pressure oil supply concave portion 51a adjacent to the concave portion 50c are adjacent to the right steering concave portion 50a, and are connected to the connecting concave portions 50c on both sides of the other second pressure oil discharging concave portion 51c. The first pressure oil discharge recess 51b and the pressure oil supply recess 51a that are adjacent to each other are adjacent to the left steering recess 50b, and the left and right steering recesses 50a and 50b that are adjacent to each of the first pressure oil discharge recesses 51b are pressed. The right steering recess 50a, which is disposed on both sides of the oil supply recess 51a and is adjacent to the pressure oil supply recess 51a, is adjacent to the first pressure oil discharge recess 51b, which is adjacent to the left steering recess 50b. Left steering recess adjacent to the supply recess 51a 0b is adjacent to the first hydraulic fluid discharge recess 51b adjacent to the right steering recess 50a.

【００３０】その第１バルブ部材３１に形成された凹部
５０ａ、５０ｂ、５０ｃの軸方向に沿う縁と第２バルブ
部材３２に形成された凹部５１ａ、５１ｂ、５１ｃの軸
方向に沿う縁との間が絞り部Ａ、Ｂ、Ｃ、Ｄ、Ｅ、Ｆ、
Ｇ、Ｈ、Ｅ′、Ｆ′、Ｇ′、Ｈ′を構成する。これによ
り、各絞り部Ａ、Ｂ、Ｃ、Ｄ、Ｅ、Ｆ、Ｇ、Ｈ、Ｅ′、
Ｆ′、Ｇ′、Ｈ′はポンプ７０とタンク７１と油圧シリ
ンダ２０とを接続する油路２７に配置されている。Between the edges of the recesses 50a, 50b, 50c formed in the first valve member 31 along the axial direction and the edges of the recesses 51a, 51b, 51c formed in the second valve member 32 along the axial direction. Are the narrowed portions A, B, C, D, E, F,
G, H, E ', F', G ', and H'are constructed. As a result, the respective throttle parts A, B, C, D, E, F, G, H, E ',
F ′, G ′, and H ′ are arranged in the oil passage 27 that connects the pump 70, the tank 71, and the hydraulic cylinder 20.

【００３１】図４に示すように、その第２バルブ部材３
２に形成された凹部５１ａ、５１ｂ、５１ｃの軸方向に
沿う縁は面取り部とされている。その圧油供給用凹部５
１ａと連絡用凹部５０ｃとの間の絞り部Ｅ、Ｅ′におけ
る圧油供給用凹部５１ａの軸方向に沿う縁と、圧油供給
用凹部５１ａに隣接する連絡用凹部５０ｃと第２圧油排
出用凹部５１ｃとの間の絞り部Ｆ、Ｆ′における第２圧
油排出用凹部５１ｃの軸方向に沿う縁（図２において△
で囲む）の面取り部の幅をＷ、その他の第２バルブ部材
３２に形成された凹部の軸方向に沿う縁（図２において
○で囲む）の面取り部の幅をＷ′として、図３、図４に
示すように、Ｗ＞Ｗ′とされている。As shown in FIG. 4, the second valve member 3 thereof
The edges of the recesses 51a, 51b, 51c formed in 2 along the axial direction are chamfered. The pressure oil supply recess 5
1a and the connecting recess 50c, the edges along the axial direction of the pressure oil supply recess 51a in the narrowed portions E, E ', the connecting recess 50c adjacent to the pressure oil supply recess 51a, and the second pressure oil discharge. An edge along the axial direction of the second pressure oil discharge concave portion 51c in the narrowed portions F and F'between the concave portion 51c for oil consumption (Δ in FIG. 2).
3, the width of the chamfered portion (enclosed by circle) is W, and the width of the chamfered portion of the other edge (encircled by circle in FIG. 2) along the axial direction of the recess formed in the second valve member 32 is W ′, As shown in FIG. 4, W> W '.

【００３２】操舵抵抗のない状態（図２〜図４の状態）
にある各絞り部Ａ、Ｂ、Ｃ、Ｄ、Ｅ、Ｆ、Ｇ、Ｈ、
Ｅ′、Ｆ′、Ｇ′、Ｈ′を全閉するのに要する両バルブ
部材３１、３２の相対回転角度（すなわち閉鎖角度）を
互いに比較すると、図４に示すように、圧油供給用凹部
５１ａと連絡用凹部５０ｃとの間の絞り部Ｅ、Ｅ′およ
び圧油供給用凹部５１ａに隣接する連絡用凹部５０ｃと
第２圧油排出用凹部５１ｃとの間の絞り部Ｆ、Ｆ′の閉
鎖角度θｒは、他の絞り部Ａ、Ｂ、Ｃ、Ｄ、Ｇ、Ｈ、
Ｇ′、Ｈ′の閉鎖角度θｔよりも大きい。これにより、
第１バルブ部材３１と第２バルブ部材３２との間の各絞
り部は、複数の絞り部Ａ、Ｂ、Ｃ、Ｄ、Ｇ、Ｈ、Ｇ′、
Ｈ′からなる第１の組と、この第１の組に属する各絞り
部よりも閉鎖角度の大きな複数の絞り部Ｅ、Ｅ′、Ｆ、
Ｆ′からなる第２の組とに組分けされる。State without steering resistance (state of FIGS. 2 to 4)
Each of the diaphragms A, B, C, D, E, F, G, H,
Comparing the relative rotation angles (that is, closing angles) of both valve members 31, 32 required to fully close E ', F', G ', H'with each other, as shown in FIG. 4, as shown in FIG. Of the narrowed portions E, E'between the 51a and the communication recessed portion 50c, and the narrowed portions F, F'between the communication recessed portion 50c adjacent to the pressure oil supply recessed portion 51a and the second pressure oil discharge recessed portion 51c The closing angle θr depends on the other throttle parts A, B, C, D, G, H,
It is larger than the closing angle θt of G ′ and H ′. This allows
Each throttle portion between the first valve member 31 and the second valve member 32 has a plurality of throttle portions A, B, C, D, G, H, G '.
A first group consisting of H'and a plurality of throttle sections E, E ', F having a larger closing angle than the throttle sections belonging to the first group.
It is divided into a second set consisting of F ′.

【００３３】その入力軸２と出力軸３は、路面から操舵
用車輪を介し伝達される抵抗によるトーションバー６の
ねじれによって相対回転する。その相対回転により第１
バルブ部材３１と第２バルブ部材３２とが相対回転する
ことで、各絞り部Ａ、Ｂ、Ｃ、Ｄ、Ｅ、Ｆ、Ｇ、Ｈ、
Ｅ′、Ｆ′、Ｇ′、Ｈ′の流路面積が変化し、油圧シリ
ンダ２０が操舵方向と操舵抵抗に応じた操舵補助力を発
生する。The input shaft 2 and the output shaft 3 rotate relative to each other due to the torsion of the torsion bar 6 due to the resistance transmitted from the road surface through the steering wheel. First by the relative rotation
By the relative rotation of the valve member 31 and the second valve member 32, each throttle portion A, B, C, D, E, F, G, H,
The flow passage areas of E ', F', G ', and H'change, and the hydraulic cylinder 20 generates a steering assist force according to the steering direction and steering resistance.

【００３４】すなわち、図２、図３は操舵が行なわれて
いない状態を示し、両バルブ部材３１、３２の間の各絞
り部Ａ、Ｂ、Ｃ、Ｄ、Ｅ、Ｆ、Ｇ、Ｈ、Ｅ′、Ｆ′、
Ｇ′、Ｈ′は全て開かれ、入口ポート３４と各出口ポー
ト３６、６１とは弁間流路２７を介し連通し、ポンプ７
０から制御バルブ３０に流入する油はタンク７１に還流
し、操舵補助力は発生しない。That is, FIGS. 2 and 3 show a state in which steering is not performed, and the throttle portions A, B, C, D, E, F, G, H, E between the valve members 31, 32 are shown. ', F',
G ′ and H ′ are all opened, and the inlet port 34 and each outlet port 36, 61 communicate with each other through the intervalve passage 27, and the pump 7
The oil flowing from 0 to the control valve 30 flows back to the tank 71, and no steering assist force is generated.

【００３５】この状態から右方へ操舵することによって
生じる操舵抵抗により両バルブ部材３１、３２が相対回
転すると、圧油供給用凹部５１ａと右操舵用凹部５０ａ
との間の絞り部Ａ、左操舵用凹部５０ｂと第１圧油排出
用凹部５１ｂとの間の絞り部Ｄ、右操舵用凹部５０ａに
隣接する圧油供給用凹部５１ａに隣接する連絡用凹部５
０ｃと第２圧油排出用凹部５１ｃとの間の絞り部Ｆ、右
操舵用凹部５０ａに隣接する第１圧油排出用凹部５１ｂ
と連絡用凹部５０ｃとの間の絞り部Ｈ、左操舵用凹部５
０ｂに隣接する圧油供給用凹部５１ａと連絡用凹部５０
ｃとの間の絞り部Ｅ′、および左操舵用凹部５０ｂに隣
接する第１圧油排出用凹部５１ｂに隣接する連絡用凹部
５０ｃと第２圧油排出用凹部５１ｃとの間の絞り部Ｇ′
の流路面積が大きくなり、他の絞り部Ｂ、Ｃ、Ｅ、Ｇ、
Ｆ′Ｈ′の流路面積が小さくなる。これにより、油圧シ
リンダ２０の右操舵補助力発生用油室２２に操舵方向と
操舵抵抗に応じた圧力の圧油が供給され、また、左操舵
補助力発生用油室２３からタンク７１に油が還流し、車
両の右方への操舵補助力が油圧シリンダ２０からラック
１６に作用する。When both valve members 31 and 32 rotate relative to each other due to the steering resistance generated by steering to the right from this state, the pressure oil supply recess 51a and the right steering recess 50a.
Between the left steering recess 50b and the first pressure oil discharge recess 51b, and a communication recess adjacent to the pressure oil supply recess 51a adjacent to the right steering recess 50a. 5
0c and the second pressure oil discharge recess 51c, and the first pressure oil discharge recess 51b adjacent to the right steering recess 50a.
And the left-hand steering recessed portion 5 between the connection recess 50c and the communication recessed portion 50c.
0b adjacent to the pressure oil supply recess 51a and the communication recess 50
c), and a narrowed portion G between the second pressure oil discharge recess 51c and the communication recess 50c adjacent to the first pressure oil discharge recess 51b adjacent to the left steering recess 50b. ′
The flow passage area of the other is increased, and other throttle parts B, C, E, G,
The flow path area of F'H 'becomes smaller. As a result, pressure oil having a pressure according to the steering direction and steering resistance is supplied to the right steering assist force generating oil chamber 22 of the hydraulic cylinder 20, and oil is supplied from the left steering assist force generating oil chamber 23 to the tank 71. The steering assist force to the right of the vehicle that flows back is applied from the hydraulic cylinder 20 to the rack 16.

【００３６】左方へ操舵すると第１バルブ部材３１と第
２バルブ部材３２とが右方に操舵した場合と逆方向に相
対回転し、絞り部Ｂ、Ｃ、Ｅ、Ｇ、Ｆ′Ｈ′の流路面積
が大きくなり、他の絞り部Ａ、Ｄ、Ｆ、Ｈ、Ｅ′、Ｇ′
の流路面積が小さくなるので、車両の左方への操舵補助
力が油圧シリンダ２０からラック１６に作用する。When steered to the left, the first valve member 31 and the second valve member 32 relatively rotate in the opposite direction to when steered to the right, and the throttles B, C, E, G, and F'H 'are rotated. The flow path area becomes large, and the other throttle parts A, D, F, H, E ', G'
Since the area of the flow path is reduced, the steering assist force to the left of the vehicle acts on the rack 16 from the hydraulic cylinder 20.

【００３７】図１に示すように、その第２出口ポート６
１に連通する可変絞り弁６０は、バルブハウジング７に
形成された挿入孔６６に図中上下方向に変位可能に挿入
されたスプール６２を有する。その挿入孔６６の各端は
プラグ６８ａ、６８ｂにより閉鎖され、一方のプラグ６
８ａにねじ込まれたバネ圧調節ネジ７９とスプール６２
の上端との間に圧縮コイルバネ６９が挿入されている。
そのスプール６２に電磁力を作用させるソレノイド６４
と、このソレノイド６４の電磁力を車速に応じ制御する
車速センサを有するコントローラ６３が設けられてい
る。これにより、高速になるとスプール６２に作用する
電磁力が小さくなりスプール６２は図中下方に変位し、
低速になるとスプール６２に作用する電磁力が大きくな
りスプール６２は図中上方に変位する。As shown in FIG. 1, its second outlet port 6
The variable throttle valve 60 communicating with 1 has a spool 62 inserted in an insertion hole 66 formed in the valve housing 7 so as to be vertically displaceable in the figure. Each end of the insertion hole 66 is closed by plugs 68a and 68b.
Spring pressure adjusting screw 79 and spool 62 screwed into 8a
A compression coil spring 69 is inserted between the upper end and the upper end of the.
Solenoid 64 that applies electromagnetic force to the spool 62
And a controller 63 having a vehicle speed sensor for controlling the electromagnetic force of the solenoid 64 according to the vehicle speed. As a result, at high speed, the electromagnetic force acting on the spool 62 is reduced, and the spool 62 is displaced downward in the figure,
When the speed becomes low, the electromagnetic force acting on the spool 62 becomes large and the spool 62 is displaced upward in the drawing.

【００３８】そのスプール６２の外周に周溝６２ａが形
成され、その挿入孔６６の内周に周溝６６ａが形成さ
れ、両周溝６２ａ、６６ａの間が可変絞り弁６０の自身
の絞り部６７とされている。この絞り部６７の流路面積
は、高速になってスプール６２が図中下方に変位すると
大きくなり、低速になってスプール６２が上方に変位す
ると小さくなる。その絞り部６７の流路面積の最大値
は、第２の組に属する絞り部Ｅ、Ｅ′、Ｆ、Ｆ′の全流
路面積の最大値以上、若しくは絞り機能を奏さなくなる
まで大きくされ、その絞り部６７の流路面積の最小値
は、第２の組に属する絞り部Ｅ、Ｅ′、Ｆ、Ｆ′の全流
路面積の最小値以下とされる。なお、各絞り部Ａ、Ｂ、
Ｃ、Ｄ、Ｅ、Ｆ、Ｇ、Ｈ、Ｅ′、Ｆ′、Ｇ′、Ｈ′の流
路面積は、操舵方向に応じて、両バルブ部材３１、３２
の相対回転角度が大きくなる程に大きくなる場合と小さ
くなる場合とがある。その流路面積が、両バルブ部材３
１、３２の相対回転角度が零の時の流路面積よりも大き
くなると、各絞り部Ａ、Ｂ、Ｃ、Ｄ、Ｅ、Ｆ、Ｇ、Ｈ、
Ｅ′、Ｆ′、Ｇ′、Ｈ′は実質的に絞り機能を奏するこ
とはない。よって、本明細書において「全流路面積」と
は、その相対回転角度が大きくなる程に流路面積が小さ
くなる絞り部における流路面積の合計をいう。従って、
第２の組に属する絞り部Ｅ、Ｅ′、Ｆ、Ｆ′の全流路面
積の最大値とは、両バルブ部材３１、３２の相対回転角
が大きくなる程に流路面積が小さくなる絞り部における
最大値であり、右操舵時は絞り部Ｅ、Ｆ′の全流路面積
の最大値をいい、左操舵時は絞り部Ｆ、Ｅ′の全流路面
積の最大値をいう。また、第２の組に属する絞り部Ｅ、
Ｅ′、Ｆ、Ｆ′の全流路面積の最小値とは、両バルブ部
材３１、３２の相対回転角が大きくなる程に流路面積が
小さくなる絞り部における最小値であり、右操舵時は絞
り部Ｅ、Ｆ′の全流路面積の最小値をいい、左操舵時は
絞り部Ｆ、Ｅ′の全流路面積の最小値をいい、全閉状態
を含む。A peripheral groove 62a is formed on the outer periphery of the spool 62, a peripheral groove 66a is formed on the inner periphery of the insertion hole 66, and the throttle portion 67 of the variable throttle valve 60 is located between the peripheral grooves 62a and 66a. It is said that. The flow passage area of the throttle portion 67 becomes large when the spool 62 is displaced downward in the drawing with a high speed, and it is reduced when the spool 62 is displaced upward with a low speed. The maximum value of the flow passage area of the throttle portion 67 is made larger than the maximum value of the total flow passage area of the throttle portions E, E ′, F, F ′ belonging to the second set, or until the throttle function is not achieved, The minimum value of the flow passage area of the throttle portion 67 is set to be equal to or smaller than the minimum value of the total flow passage area of the throttle portions E, E ′, F, F ′ belonging to the second set. It should be noted that each throttle unit A, B,
The flow passage area of C, D, E, F, G, H, E ', F', G ', H'depends on the steering direction.
There is a case where the relative rotation angle of becomes larger and a case where the relative rotation angle becomes smaller. The flow passage area is such that both valve members 3
When the relative rotation angle of 1, 32 becomes larger than the flow path area when the relative rotation angle is zero, each throttle portion A, B, C, D, E, F, G, H,
E ', F', G ', and H'do not substantially have a diaphragm function. Therefore, in the present specification, the "total flow passage area" refers to the total flow passage area in the throttle portion where the flow passage area decreases as the relative rotation angle increases. Therefore,
The maximum value of the total flow passage area of the throttle portions E, E ′, F, F ′ belonging to the second set means that the flow passage area decreases as the relative rotation angle of both valve members 31, 32 increases. The maximum value of the total flow passage area of the throttles E and F'when steering to the right, and the maximum value of the total flow passage area of the throttles F and E'when steering to the left. Further, the diaphragm portion E belonging to the second group,
The minimum value of the total flow passage area of E ', F, F'is the minimum value in the throttle portion where the flow passage area becomes smaller as the relative rotation angle of both valve members 31, 32 becomes larger. Indicates the minimum value of the total flow passage area of the throttle portions E and F ′, and the minimum value of the total flow passage area of the throttle portions F and E ′ during left steering, including the fully closed state.

【００３９】その可変絞り弁６０の自身の絞り部６７と
第２出口ポート６１とを連通する流路５８がバルブハウ
ジング７に形成され、その絞り部６７とスプール６２の
上方空間とを連通する通孔７５がスプール６６に形成さ
れ、そのスプール６２の上方空間と第１出口ポート３６
とを連通する流路７６がバルブハウジング７に形成され
ている。これにより、図５に示す油圧回路が構成され、
第２の組に属する絞り部Ｅ、Ｅ′、Ｆ、Ｆ′とタンク７
１との間の油路の流路面積が、車速に応じた可変絞り弁
６０の作動により変化する。なお、スプール６２の下方
空間と上方空間とを連通するドレン通路７８が、そのス
プール６２に形成されている。A flow path 58 is formed in the valve housing 7 to connect the throttle portion 67 of the variable throttle valve 60 to the second outlet port 61, and to connect the throttle portion 67 to the space above the spool 62. A hole 75 is formed in the spool 66, the space above the spool 62 and the first outlet port 36.
A flow path 76 is formed in the valve housing 7 for communicating with the valve housing 7. This constitutes the hydraulic circuit shown in FIG.
The throttles E, E ', F, F'and the tank 7 belonging to the second set
The flow passage area of the oil passage between 1 and 1 changes due to the operation of the variable throttle valve 60 according to the vehicle speed. A drain passage 78 that connects the lower space and the upper space of the spool 62 is formed in the spool 62.

【００４０】上記構成によれば、低速走行時や据え切り
時においては、スプール６２は図１において上方に変位
し、このスプール６２の変位により可変絞り弁６０の自
身の絞り部６７は全閉状態になる。よって、油圧シリン
ダ２０に作用する油圧は、第１の組の絞り部Ａ、Ｂ、
Ｃ、Ｄ、Ｇ、Ｈ、Ｇ′、Ｈ′の流路面積の変化に応じ制
御され、図１０において一点鎖線で示すように、操舵入
力トルクが小さく両バルブ部材３１、３２の相対回転角
が小さくても、第１の組に属する絞り部Ａ、Ｂ、Ｃ、
Ｄ、Ｇ、Ｈ、Ｇ′、Ｈ′の流路面積を小さくし、操舵補
助力を発生させる油圧の増加割合を大きくし、低速走行
時における操舵の高応答性を満足させることができる。According to the above construction, the spool 62 is displaced upward in FIG. 1 when the vehicle is running at low speed or stationary, and the displacement of the spool 62 causes the throttle portion 67 of the variable throttle valve 60 to be fully closed. become. Therefore, the hydraulic pressure acting on the hydraulic cylinder 20 is limited to the first set of throttle portions A, B,
Control is performed according to changes in the flow passage areas of C, D, G, H, G ′, and H ′, and as indicated by the alternate long and short dash line in FIG. 10, the steering input torque is small and the relative rotation angles of both valve members 31, 32 are small. Even if small, the diaphragm units A, B, C belonging to the first group,
It is possible to reduce the flow passage areas of D, G, H, G ′, and H ′, increase the increase rate of the hydraulic pressure that generates the steering assist force, and satisfy the high responsiveness of steering during low speed traveling.

【００４１】高速走行時においては、スプール６２は図
１において下方に変位し、このスプール６２の変位によ
り可変絞り弁６０の自身の絞り部６７の流路面積は、第
２の組に属する絞り部Ｅ、Ｅ′、Ｆ、Ｆ′の全流路面積
の最大値以上になる。よって、油圧シリンダ２０に作用
する油圧は、第２の組の絞り部Ｅ、Ｅ′、Ｆ、Ｆ′の流
路面積の変化と、第１の組の絞り部Ａ、Ｂ、Ｃ、Ｄ、
Ｇ、Ｈ、Ｇ′、Ｈ′の流路面積の変化との合成特性に応
じ制御される。これにより、図１０において実線で示す
ように、操舵入力トルクを大きくして両バルブ部材３
１、３２の相対回転角を大きくしない限り、第２の組に
属する絞り部Ｅ、Ｅ′、Ｆ、Ｆ′の流路面積は小さくな
ることなく大きく保持され、操舵補助力を発生させる油
圧の増加割合は小さいので、高速走行時における操舵の
安定性を満足させることができる。During high speed traveling, the spool 62 is displaced downward in FIG. 1, and the displacement of the spool 62 causes the flow passage area of the throttle portion 67 of the variable throttle valve 60 itself to be the throttle portion belonging to the second group. It becomes equal to or larger than the maximum value of the total flow passage area of E, E ', F, F'. Therefore, the hydraulic pressure acting on the hydraulic cylinder 20 is changed by the change in the flow passage area of the second set of throttle portions E, E ′, F, F ′ and the first set of throttle portions A, B, C, D ,.
It is controlled in accordance with the combined characteristics of G, H, G ', and H'changes in the flow path area. As a result, as shown by the solid line in FIG.
Unless the relative rotation angles of 1 and 32 are increased, the flow passage areas of the throttle portions E, E ', F, and F'belonging to the second set are kept large without decreasing, and the hydraulic pressure for generating the steering assist force is maintained. Since the rate of increase is small, it is possible to satisfy the steering stability during high-speed traveling.

【００４２】また、中速走行時においては、車速に応じ
て可変絞り弁６０の絞り部６７の開度が変化するので、
操舵の高応答性と安定性とを満足させることができる。In addition, since the opening degree of the throttle portion 67 of the variable throttle valve 60 changes according to the vehicle speed at the time of traveling at medium speed,
High responsiveness and stability of steering can be satisfied.

【００４３】[0043]

【第２実施例】以下、図６、図７を参照して第２実施例
を説明する。なお、第２実施例においては、第１実施例
と同様の構成は図面において第１実施例と同一符号を付
して重複説明を省略し、相違点を説明する。[Second Embodiment] A second embodiment will be described below with reference to FIGS. 6 and 7. In the second embodiment, the same components as those in the first embodiment will be designated by the same reference numerals in the drawings, redundant description will be omitted, and different points will be described.

【００４４】図６に示すように、第１バルブ部材３１の
内周に１２ケの凹部５０ａ、５０ｂ、５０ｃが周方向に
関し互いに等間隔に形成され、第２バルブ部材３２の外
周に１２ケの凹部５１ａ、５１ｂ、５１ｃが周方向に関
し互いに等間隔に形成されている。As shown in FIG. 6, twelve recesses 50a, 50b, 50c are formed on the inner circumference of the first valve member 31 at equal intervals in the circumferential direction, and twelve recesses are formed on the outer circumference of the second valve member 32. Recesses 51a, 51b, 51c are formed at equal intervals in the circumferential direction.

【００４５】その第１バルブ部材３１に形成された凹部
は、２ケの右操舵用凹部５０ａと、２ケの左操舵用凹部
５０ｂと、８ケの連絡用凹部５０ｃとを構成する。The recesses formed in the first valve member 31 form two right steering recesses 50a, two left steering recesses 50b, and eight connecting recesses 50c.

【００４６】その第２バルブ部材３２に形成された凹部
は、４ケの圧油供給用凹部５１ａと、４ケの第１圧油排
出用凹部５１ｂと、４ケの第２圧油排出用凹部５１ｃと
を構成する。The recesses formed in the second valve member 32 include four pressure oil supply recesses 51a, four first pressure oil discharge recesses 51b, and four second pressure oil discharge recesses. 51c.

【００４７】各第２圧油排出用凹部５１ｃの両隣に連絡
用凹部５０ｃが配置され、各第２圧油排出用凹部５１ｃ
の両隣の連絡用凹部５０ｃの一方は第１圧油排出用凹部
５１ｂに隣接すると共に他方は圧油供給用凹部５１ａに
隣接し、各連絡用凹部５０ｃに隣接する圧油供給用凹部
５１ａは第１圧油排出用凹部５１ｂの両隣の左右操舵用
凹部５０ａ、５０ｂに隣接する。Communication recesses 50c are arranged on both sides of each second pressure oil discharge recess 51c, and each second pressure oil discharge recess 51c.
One of the connecting recesses 50c adjacent to each other is adjacent to the first pressure oil discharge recess 51b and the other is adjacent to the pressure oil supply recess 51a. The pressure oil supply recess 51a adjacent to each connecting recess 50c is It is adjacent to the left and right steering recesses 50a and 50b on both sides of the first pressure oil discharge recess 51b.

【００４８】図６は操舵が行なわれていない状態を示
し、この状態から右方へ操舵することによって生じる操
舵抵抗により両バルブ部材３１、３２が相対回転する
と、圧油供給用凹部５１ａと右操舵用凹部５０ａとの間
の絞り部Ａ、左操舵用凹部５０ｂと第１圧油排出用凹部
５１ｂとの間の絞り部Ｄ、右操舵用凹部５０ａに隣接す
る圧油供給用凹部５１ａに隣接する連絡用凹部５０ｃと
第２圧油排出用凹部５１ｃとの間の絞り部Ｆ、右操舵用
凹部５０ａに隣接する圧油供給用凹部５１ａに隣接する
連絡用凹部５０ｃに隣接する第２圧油排出用凹部５１ｃ
に隣接する連絡用凹部５０ｃと第１圧油排出用凹部５１
ｂとの間の絞り部Ｈ、左操舵用凹部５０ｂに隣接する圧
油供給用凹部５１ａと連絡用凹部５０ｃとの間の絞り部
Ｅ′、および左操舵用凹部５０ｂに隣接する圧油供給用
凹部５１ａに隣接する連絡用凹部５０ｃに隣接する第２
圧油排出用凹部５１ｃと連絡用凹部５０ｃとの間の絞り
部Ｇ′の流路面積が大きくなり、他の絞り部Ｂ、Ｃ、
Ｅ、Ｇ、Ｆ′Ｈ′の流路面積が小さくなる。これによ
り、油圧シリンダ２０の右操舵補助力発生用油室２２に
操舵方向と操舵抵抗に応じた圧力の圧油が供給され、ま
た、左操舵補助力発生用油室２３からタンク７１に油が
還流し、車両の右方への操舵補助力が油圧シリンダ２０
からラック１６に作用する。FIG. 6 shows a state in which steering is not performed. When both valve members 31 and 32 rotate relative to each other due to steering resistance generated by steering to the right from this state, the pressure oil supply recess 51a and the right steering are provided. Adjacent to the pressure oil supply concave portion 51a adjacent to the right steering concave portion 50a and the throttle portion D between the left steering concave portion 50b and the first pressure oil discharging concave portion 51b. The narrowed portion F between the communication recess 50c and the second pressure oil discharge recess 51c, the second pressure oil discharge adjacent to the communication recess 50c adjacent to the pressure oil supply recess 51a adjacent to the right steering recess 50a. Recess 51c
Connecting recess 50c and first pressure oil discharge recess 51 adjacent to
b, a throttle portion H between b, a throttle portion E'between the pressure oil supply concave portion 51a adjacent to the left steering concave portion 50b and the communication concave portion 50c, and a pressure oil supply adjacent to the left steering concave portion 50b. Second adjacent to the communication recess 50c adjacent to the recess 51a
The flow passage area of the throttle portion G ′ between the pressure oil discharge recessed portion 51c and the communication recessed portion 50c becomes large, and the other throttle portions B, C,
The flow passage areas of E, G and F'H 'are reduced. As a result, pressure oil having a pressure according to the steering direction and steering resistance is supplied to the right steering assist force generating oil chamber 22 of the hydraulic cylinder 20, and oil is supplied from the left steering assist force generating oil chamber 23 to the tank 71. The steering assist force to the right of the vehicle is returned to the hydraulic cylinder 20.
Acts on the rack 16.

【００４９】左方へ操舵すると第１バルブ部材３１と第
２バルブ部材３２とが右方に操舵した場合と逆方向に相
対回転し、絞り部Ｂ、Ｃ、Ｅ、Ｇ、Ｆ′Ｈ′の流路面積
が大きくなり、他の絞り部Ａ、Ｄ、Ｆ、Ｈ、Ｅ′、Ｇ′
の流路面積が小さくなるので、車両の左方への操舵補助
力が油圧シリンダ２０からラック１６に作用する。When steered to the left, the first valve member 31 and the second valve member 32 relatively rotate in the opposite direction to those when steered to the right, and the throttles B, C, E, G, and F'H 'are rotated. The flow path area becomes large, and the other throttle parts A, D, F, H, E ', G'
Since the area of the flow path is reduced, the steering assist force to the left of the vehicle acts on the rack 16 from the hydraulic cylinder 20.

【００５０】他は第１実施例と同様の構成で、図７に示
す油圧回路が構成され、第２の組に属する絞り部Ｅ、
Ｅ′、Ｆ、Ｆ′とタンク７１との間の油路の流路面積
が、車速に応じた可変絞り弁６０の作動により変化する
ことで、第１実施例と同様の作用効果を奏する。Other than that, the hydraulic circuit shown in FIG. 7 is constructed with the same construction as in the first embodiment, and the throttle portions E belonging to the second group,
The flow passage area of the oil passage between E ′, F, F ′ and the tank 71 is changed by the operation of the variable throttle valve 60 according to the vehicle speed, so that the same effect as the first embodiment is obtained.

【００５１】上記各実施例の構成によれば、第２の組に
属する絞り部Ｅ、Ｅ′、Ｆ、Ｆ′は、圧油供給用凹部５
１ａと連絡用凹部５０ｃとの間、および、圧油供給用凹
部５１ａに隣接する連絡用凹部５０ｃと第２圧油排出用
凹部５１ｃとの間に位置し、各第２圧油排出用凹部５１
ｃの両隣に連絡用凹部５０ｃが配置され、各第２圧油排
出用凹部５１ｃの両隣の連絡用凹部５０ｃの一方は第１
圧油排出用凹部５１ｂに隣接すると共に他方は圧油供給
用凹部５１ａに隣接する。よって、低速走行時や据え切
り時に可変絞り弁６０の絞り部６７を全閉としても、第
２の組に属する絞り部Ｅ、Ｅ′、Ｆ、Ｆ′において圧油
を流動させることができる。しかも、その可変絞り弁６
０の絞り部６７を全閉とした場合、第２の組に属する絞
り部Ｅ、Ｅ′、Ｆ、Ｆ′において流動する圧油は、第２
圧油排出用凹部５１ｃと一方の連絡用凹部５０ｃとの間
の第１の組に属する絞り部Ｇ、Ｇ′、および、その一方
の連絡用凹部５０ｃと第１圧油排出用凹部５１ｂとの間
の第１の組に属する絞り部Ｈ、Ｈ′を介して第１圧油排
出用凹部５１ｂに至るので、第１の組に属する絞り部
Ａ、Ｂ、Ｃ、Ｄ、Ｇ、Ｈ、Ｇ′、Ｈ′の流路面積変化の
みに応じて油圧シリンダ２０に作用する油圧を制御でき
る。これにより、低速走行時や据え切り時における各バ
ルブ部材に対する油圧の作用位置を増加させるために、
各バルブ部材３１、３２に形成する凹部の数を、従来よ
りも少なくすることができる。すなわち、その低速走行
時や据え切り時における油圧の作用位置を４位置とする
のに、従来であれば各バルブ部材それぞれに形成する凹
部の数を１６ケとする必要があったのに対し、第１実施
例によれば１０ケでよく、第２実施例によれば１２ケで
よい。これにより、加工コストの増大や装置の大型化を
招くことなく、バルブ部材３１、３２の変形による作動
不良と流動音の発生とを防止できる。According to the constitution of each of the above-mentioned embodiments, the throttle portions E, E ', F, F'belonging to the second set are the pressure oil supplying recesses 5.
1a and the recessed part 50c for connection, and between the recessed part 51c for connection and the second recessed part 51c for discharging pressure oil which are adjacent to the recessed part 51a for supplying pressured oil, each second recessed part 51c for discharging hydraulic oil.
The communication recesses 50c are disposed on both sides of the second pressure oil discharge recesses 51c.
It is adjacent to the pressure oil discharge recess 51b and the other is adjacent to the pressure oil supply recess 51a. Therefore, even when the throttle portion 67 of the variable throttle valve 60 is fully closed during low speed traveling or stationary operation, the pressure oil can be made to flow in the throttle portions E, E ′, F, F ′ belonging to the second group. Moreover, the variable throttle valve 6
When the throttle portion 67 of 0 is fully closed, the pressure oil flowing in the throttle portions E, E ′, F, F ′ belonging to the second set is the second
The throttles G and G'which belong to the first set between the pressure oil discharge recess 51c and the one communication recess 50c, and the one communication recess 50c and the first pressure oil discharge recess 51b. Since the first pressure oil discharge concave portion 51b is reached via the throttle portions H and H'belonging to the first set, the throttle portions A, B, C, D, G, H and G belonging to the first set. The hydraulic pressure acting on the hydraulic cylinder 20 can be controlled only in accordance with the change of the flow passage area of ', H'. As a result, in order to increase the operating position of the hydraulic pressure on each valve member during low speed running or stationary steering,
The number of recesses formed in each valve member 31, 32 can be made smaller than in the conventional case. That is, in order to set the hydraulic pressure application position to four positions during low speed running or stationary steering, it is necessary to set the number of recesses formed in each valve member to 16 in the past. According to the first embodiment, it may be ten, and according to the second embodiment, it may be twelve. As a result, it is possible to prevent defective operation and generation of flow noise due to deformation of the valve members 31 and 32 without increasing the processing cost and increasing the size of the apparatus.

【００５２】なお、本発明は上記各実施例に限定される
ものではない。例えば、上記実施例では本発明をラック
ピニオン式油圧パワーステアリング装置に適用したが、
例えばボールスクリュー式油圧パワーステアリング装置
にも適用することができる。また、上記実施例では可変
絞り弁の流路面積を車速に応じ変化させたが、例えば操
舵角のような他の運転条件に応じ変化させてもよい。The present invention is not limited to the above embodiments. For example, in the above embodiment, the present invention is applied to the rack and pinion type hydraulic power steering device,
For example, it can be applied to a ball screw type hydraulic power steering device. Further, in the above embodiment, the flow passage area of the variable throttle valve is changed according to the vehicle speed, but it may be changed according to other driving conditions such as steering angle.

【００５３】[0053]

【発明の効果】本発明の油圧パワーステアリング装置に
よれば、加工コストの増大や装置の大型化を招くことな
く、バルブ部材の変形による作動不良と流動音の発生と
を防止できる。According to the hydraulic power steering apparatus of the present invention, it is possible to prevent malfunction and flow noise due to deformation of the valve member without increasing the processing cost and increasing the size of the apparatus.

【図面の簡単な説明】[Brief description of drawings]

【図１】第１実施例の油圧パワーステアリング装置の縦
断面図FIG. 1 is a vertical sectional view of a hydraulic power steering device according to a first embodiment.

【図２】第１実施例の制御バルブの横断面構造の説明図FIG. 2 is an explanatory view of a cross-sectional structure of the control valve of the first embodiment.

【図３】第１実施例の制御バルブの展開図FIG. 3 is a development view of the control valve of the first embodiment.

【図４】第１実施例の制御バルブの要部の拡大図FIG. 4 is an enlarged view of a main part of the control valve of the first embodiment.

【図５】第１実施例の油圧パワーステアリング装置の油
圧回路を示す図FIG. 5 is a diagram showing a hydraulic circuit of the hydraulic power steering system according to the first embodiment.

【図６】第２実施例の制御バルブの横断面構造の説明図FIG. 6 is an explanatory diagram of a cross-sectional structure of the control valve of the second embodiment.

【図７】第２実施例の油圧パワーステアリング装置の油
圧回路を示す図FIG. 7 is a diagram showing a hydraulic circuit of a hydraulic power steering system according to a second embodiment.

【図８】従来例の制御バルブの横断面構造の説明図FIG. 8 is an explanatory view of a cross-sectional structure of a conventional control valve.

【図９】従来例の油圧パワーステアリング装置の油圧回
路を示す図FIG. 9 is a diagram showing a hydraulic circuit of a conventional hydraulic power steering device.

【図１０】油圧パワーステアリング装置における入力ト
ルクと油圧との関係及び両バルブ部材の相対回転角と油
圧との関係を示す図FIG. 10 is a diagram showing a relationship between an input torque and a hydraulic pressure in a hydraulic power steering device and a relationship between a relative rotation angle of both valve members and a hydraulic pressure.

【符号の説明】[Explanation of symbols]

２０油圧シリンダ３０油圧制御バルブ３１第１バルブ部材３２第２バルブ部材５０ａ右操舵用凹部５０ｂ左操舵用凹部５０ｃ連絡用凹部５１ａ圧油供給用凹部５１ｂ第１圧油排出用凹部５１ｃ第２圧油排出用凹部６０可変絞り弁７０ポンプ７１タンクＡ、Ｂ、Ｃ、Ｄ、Ｅ、Ｆ、Ｇ、Ｈ、Ｅ′、Ｆ′、Ｇ′、
Ｈ′ 絞り部20 Hydraulic Cylinder 30 Hydraulic Control Valve 31 First Valve Member 32 Second Valve Member 50a Right Steering Recess 50b Left Steering Recess 50c Communication Recess 51a Pressure Oil Supply Recess 51b First Pressure Oil Recess 51c Second Pressure Oil Discharge recess 60 Variable throttle valve 70 Pump 71 Tank A, B, C, D, E, F, G, H, E ', F', G ',
H'throttle

Claims

【特許請求の範囲】[Claims]

【請求項１】操舵補助力発生用油圧アクチュエータ
と、油圧制御バルブとを備え、その油圧制御バルブは、筒状の第１バルブ部材と、この
第１バルブ部材に操舵抵抗に応じ相対回転可能に挿入さ
れる第２バルブ部材とを有し、両バルブ部材の間は、その操舵補助力発生用油圧アクチ
ュエータをポンプとタンクとに接続する油路とされ、その第１バルブ部材の内周に複数の凹部が互いに周方向
の間隔をおいて形成され、その第２バルブ部材の外周に
複数の凹部が互いに周方向の間隔をおいて形成され、そ
の第１バルブ部材に形成された凹部の間に第２バルブ部
材に形成された凹部が位置し、それら凹部は、ポンプに接続される複数の圧油供給用凹
部と、タンクに接続される複数の第１圧油排出用凹部
と、運転条件に応じ自身の絞り部の流路面積を変化させ
る可変絞り弁を介してタンクに接続される複数の第２圧
油排出用凹部と、油圧アクチュエータの右操舵補助力発
生用油室に接続される複数の右操舵用凹部と、油圧アク
チュエータの左操舵補助力発生用油室に接続される複数
の左操舵用凹部と、複数の連絡用凹部とを構成し、その第１バルブ部材に形成された凹部の軸方向に沿う縁
と第２バルブ部材に形成された凹部の軸方向に沿う縁と
の間が絞り部を構成し、各絞り部は、操舵方向と操舵抵
抗に応じた両バルブ部材の相対回転により操舵補助力を
付与できるように前記油路に配置される油圧パワーステ
アリング装置において、各第２圧油排出用凹部の両隣に連絡用凹部が配置され、
各第２圧油排出用凹部の両隣の連絡用凹部の一方は第１
圧油排出用凹部に隣接すると共に他方は圧油供給用凹部
に隣接し、圧油供給用凹部と連絡用凹部との間の絞り部と、圧油供
給用凹部に隣接する連絡用凹部と第２圧油排出用凹部と
の間の絞り部とは第２の組に属し、他の絞り部は第１の
組に属し、第２の組に属する絞り部の閉鎖角度は第１の
組に属する絞り部の閉鎖角度よりも大きくされている油
圧パワーステアリング装置。1. A hydraulic actuator for generating a steering assist force and a hydraulic control valve, wherein the hydraulic control valve is a cylindrical first valve member and is rotatable relative to the first valve member in accordance with steering resistance. A second valve member to be inserted, and between the two valve members is an oil passage connecting the steering assist force generating hydraulic actuator to the pump and the tank, and a plurality of oil passages are provided on the inner periphery of the first valve member. Recesses are formed at intervals in the circumferential direction, and a plurality of recesses are formed on the outer circumference of the second valve member at intervals in the circumferential direction, and between the recesses formed in the first valve member. The recesses formed in the second valve member are located, and these recesses include a plurality of pressure oil supply recesses connected to the pump, a plurality of first pressure oil discharge recesses connected to the tank, and operating conditions. According to the flow path of its own throttle A plurality of second pressure oil discharge recesses connected to the tank via a variable throttle valve that changes the product; a plurality of right steering recesses connected to the right steering assist force generating oil chamber of the hydraulic actuator; A plurality of left steering recesses connected to the left steering assist force generating oil chamber of the actuator, and a plurality of communication recesses are formed, and an edge of the recess formed in the first valve member along the axial direction and a first A throttle portion is formed between an axial edge of a recess formed in the two valve members, and each throttle portion can apply a steering assist force by relative rotation of both valve members according to the steering direction and steering resistance. In the hydraulic power steering device arranged in the oil passage as described above, the connection recesses are arranged on both sides of each second pressure oil discharge recess,
One of the communication recesses on both sides of each second pressure oil discharge recess is the first
Adjacent to the pressure oil discharge concave portion and the other adjacent to the pressure oil supply concave portion, the throttle portion between the pressure oil supply concave portion and the communication concave portion, and the communication concave portion adjacent to the pressure oil supply concave portion The throttle portion between the second pressure oil discharge concave portion belongs to the second group, the other throttle portions belong to the first group, and the closing angles of the throttle sections belonging to the second group belong to the first group. A hydraulic power steering device that is larger than the closing angle of the throttle to which it belongs.

【請求項２】その第１バルブ部材の内周に形成される
凹部は１０ケとされ、その第２バルブ部材の外周に形成
される凹部は１０ケとされ、それら凹部は、ポンプに接続される４ケの圧油供給用凹
部と、タンクに接続される４ケの第１圧油排出用凹部
と、運転条件に応じ自身の絞り部の流路面積を変化させ
る可変絞り弁を介してタンクに接続される２ケの第２圧
油排出用凹部と、油圧アクチュエータの右操舵補助力発
生用油室に接続される３ケの右操舵用凹部と、油圧アク
チュエータの左操舵補助力発生用油室に接続される３ケ
の左操舵用凹部と、４ケの連絡用凹部とを構成し、各第２圧油排出用凹部の両隣に連絡用凹部が配置され、
各第２圧油排出用凹部の両隣の連絡用凹部の一方は第１
圧油排出用凹部に隣接すると共に他方は圧油供給用凹部
に隣接し、一方の第２圧油排出用凹部の両隣の各連絡用
凹部に隣接する第１圧油排出用凹部と圧油供給用凹部と
は右操舵用凹部に隣接し、他方の第２圧油排出用凹部の
両隣の各連絡用凹部に隣接する第１圧油排出用凹部と圧
油供給用凹部とは左操舵用凹部に隣接し、その各第１圧
油排出用凹部に隣接する左右操舵用凹部は圧油供給用凹
部の両隣に配置され、その圧油供給用凹部に隣接する右
操舵用凹部は左操舵用凹部に隣接する第１圧油排出用凹
部に隣接し、その圧油供給用凹部に隣接する左操舵用凹
部は右操舵用凹部に隣接する第１圧油排出用凹部に隣接
する請求項１に記載の油圧パワーステアリング装置。2. The first valve member has 10 recesses formed on the inner periphery thereof, and the second valve member has 10 recesses formed on the outer periphery thereof, the recesses being connected to a pump. Tanks via four pressure oil supply recesses, four first pressure oil discharge recesses connected to the tank, and a variable throttle valve that changes the flow passage area of its own throttle portion according to operating conditions. Two second pressure oil discharge recesses connected to the hydraulic actuator, three right steering assist force generation oil recesses connected to the hydraulic actuator right steering assist force generating oil chamber, and a hydraulic actuator left steering assist force generation oil. 3 left steering recesses and 4 connecting recesses connected to the chamber are formed, and the connecting recesses are arranged on both sides of each of the second pressure oil discharge recesses,
One of the communication recesses on both sides of each second pressure oil discharge recess is the first
A first pressure oil discharge recess and a pressure oil supply adjacent to the pressure oil discharge recess and the other adjacent to the pressure oil supply recess, and adjacent to the respective communication recesses on both sides of one of the second pressure oil discharge recesses. The first pressure oil discharge concave portion and the pressure oil supply concave portion are adjacent to the right steering concave portion and adjacent to the respective communication concave portions on both sides of the other second pressure oil discharging concave portion. The right and left steering recesses adjacent to the first pressure oil discharge recesses are disposed on both sides of the pressure oil supply recess, and the right steering recesses adjacent to the pressure oil supply recesses are the left steering recesses. The first pressure oil discharge recess adjacent to the first pressure oil discharge recess, and the left steering recess adjacent to the pressure oil supply recess is adjacent to the first pressure oil discharge recess adjacent to the right steering recess. Hydraulic power steering device.

【請求項３】その第１バルブ部材の内周に形成される
凹部は１２ケとされ、その第２バルブ部材の外周に形成
される凹部は１２ケとされ、それら凹部は、ポンプに接続される４ケの圧油供給用凹
部と、タンクに接続される４ケの第１圧油排出用凹部
と、運転条件に応じ自身の絞り部の流路面積を変化させ
る可変絞り弁を介してタンクに接続される４ケの第２圧
油排出用凹部と、油圧アクチュエータの右操舵補助力発
生用油室に接続される２ケの右操舵用凹部と、油圧アク
チュエータの左操舵補助力発生用油室に接続される２ケ
の左操舵用凹部と、８ケの連絡用凹部とを構成し、各第２圧油排出用凹部の両隣に連絡用凹部が配置され、
各第２圧油排出用凹部の両隣の連絡用凹部の一方は第１
圧油排出用凹部に隣接すると共に他方は圧油供給用凹部
に隣接し、各連絡用凹部に隣接する圧油供給用凹部は第
１圧油排出用凹部の両隣の左右圧油供給用凹部に隣接す
る請求項１に記載の油圧パワーステアリング装置。3. The first valve member has 12 recesses formed on the inner circumference thereof, and the second valve member has 12 recesses formed on the outer circumference thereof, the recesses being connected to a pump. Tanks via four pressure oil supply recesses, four first pressure oil discharge recesses connected to the tank, and a variable throttle valve that changes the flow passage area of its own throttle portion according to operating conditions. To the second hydraulic oil discharge recess, two right steering recesses connected to the hydraulic actuator right steering assist force generating oil chamber, and the hydraulic actuator left steering assist force generating oil. 2 left steering recesses and 8 connecting recesses connected to the chamber are formed, and the connecting recesses are arranged on both sides of each of the second pressure oil discharge recesses,
One of the communication recesses on both sides of each second pressure oil discharge recess is the first
The pressure oil supply recesses are adjacent to the pressure oil discharge recess and the other is adjacent to the pressure oil supply recess, and the pressure oil supply recesses adjacent to the respective communication recesses are left and right pressure oil supply recesses on both sides of the first pressure oil discharge recess. The hydraulic power steering device according to claim 1, which is adjacent to each other.