JPS6132849Y2 - - Google Patents

Description

【考案の詳細な説明】 本考案は動力舵取装置の操舵力制御装置に関
し、停止時又は低速時には軽快な操舵力が、高速
時には重く安定した操舵力が得られるようにした
ものである。[Detailed Description of the Invention] The present invention relates to a steering force control device for a power steering device, and is designed to provide a light steering force when stopped or at low speeds, and a heavy and stable steering force at high speeds.

従来、この種の操舵力制御装置として、ポンプ
と動力舵取装置とを接続する流路の途中に流路切
換弁を設け、車両の速度が所定速度以上の高速と
なつた際には上記流路切換弁を作動させて動力舵
取装置の供給側流路を瞬間的に貯槽に連通させる
ようにしたもの、或いは上記流路切換弁の代わり
に流量制御弁を設け、車両の速度が高速となるに
従つて動力舵取装置への供給量を減少させるよう
にしたものが知られている。しかしながら前者の
装置では、操舵中に動力舵取装置の供給側流路が
瞬間的に貯槽に連通されると操舵力が急激に変化
して運転者に不快感を与えるという欠点があり、
一方、後者の装置ではそのように欠点は解消され
るが、その反面、高速時にも動力舵取装置に微少
の圧油を供給し続けることから、高速時の操舵力
を充分に大きくすることができないという欠点が
あつた。 Conventionally, as this type of steering force control device, a flow path switching valve is provided in the middle of the flow path connecting the pump and the power steering device, and when the speed of the vehicle becomes higher than a predetermined speed, the flow path is switched off. A system in which the supply side flow path of the power steering device is instantaneously communicated with the storage tank by operating a path switching valve, or a flow control valve is installed in place of the flow path switching valve, and the speed of the vehicle is high. A system is known in which the amount of power supplied to the power steering device is reduced as the power becomes larger. However, the former device has the disadvantage that when the supply side flow path of the power steering device is momentarily communicated with the storage tank during steering, the steering force changes suddenly, causing discomfort to the driver.
On the other hand, although the latter device eliminates this drawback, on the other hand, it continues to supply a small amount of pressure oil to the power steering device even at high speeds, making it difficult to sufficiently increase the steering force at high speeds. The drawback was that I couldn't do it.

したがつて、流量制御弁と流路切換弁とを設け
れば、上記従来装置のそれぞれの欠点を解消でき
ることが理解される。 Therefore, it is understood that by providing a flow rate control valve and a flow path switching valve, each of the drawbacks of the above-mentioned conventional devices can be overcome.

本考案は、流量制御弁と流路切換弁とを設ける
に当つて、流量制御弁が車速の増大に応じて供給
量を減少させることに着目し、その供給量が所定
量以下になつたときに自動的に上記供給側流路を
貯槽に連通させる流路切換弁を用いることによ
り、格別な流路切換弁の駆動手段を要しない極め
て簡単な構成で操舵力を連続的に変化させ、しか
も高速時には充分な大きさの操舵力を得られるよ
うにしたものである。 In providing a flow control valve and a flow path switching valve, the present invention focuses on the fact that the flow control valve reduces the supply amount as the vehicle speed increases, and when the supply amount falls below a predetermined amount. By using a flow path switching valve that automatically communicates the supply side flow path with the storage tank, the steering force can be continuously changed with an extremely simple configuration that does not require any special driving means for the flow path switching valve. This allows sufficient steering force to be obtained at high speeds.

以下本考案の一実施例を図に基づいて詳細に説
明すると、１は導管２の途中に配設したポンプ
で、この導管２の一端は貯槽３に、他端は後に詳
述する流量制御弁４の流入口５に接続している。
６は一端を上記流量制御弁４の流出口７に接続し
た導管で、該導管６の他端は公知の動力舵取装置
８の供給口に接続し、該動力舵取装置８の排出口
は導管９、導管１０及び導管１１を介して上記貯
槽３に、また上記流量制御弁４の排出口１２は導
管１０及び導管１１を介して貯槽３にそれぞれ連
通されている。 An embodiment of the present invention will be described below in detail based on the drawings. 1 is a pump disposed in the middle of a conduit 2, one end of this conduit 2 is connected to a storage tank 3, and the other end is a flow control valve which will be described in detail later. It is connected to the inlet 5 of 4.
Reference numeral 6 denotes a conduit whose one end is connected to the outlet 7 of the flow rate control valve 4, the other end of which is connected to the supply port of a known power steering device 8, and the outlet of the power steering device 8 is The outlet 12 of the flow control valve 4 is communicated with the storage tank 3 via conduits 9, 10, and 11, and the outlet 12 of the flow control valve 4 is communicated with the storage tank 3 via conduits 10 and 11, respectively.

なお、１３は上記ポンプ１と流量制御弁４の流
入口５との間の導管２に設けたリリーフ弁で、該
リリーフ弁１３に上記導管１１を接続してある。 Note that 13 is a relief valve provided in the conduit 2 between the pump 1 and the inlet 5 of the flow rate control valve 4, and the conduit 11 is connected to the relief valve 13.

然して、１４は前記流量制御弁４に設けたソレ
ノイド装置、１５，１６はそれぞれソレノイド装
置１４を構成するコイルとプランジヤである。該
プランジヤ１６の先端には針状軸体１７の末端が
連結してあり、該プランジヤ１６の中央部に形成
したフランジ１８にばね１９の弾撥力を作用さ
せ、通常は該プランジヤ１６及び針状軸体１７を
図に示す後退端に位置させている。２０は速度
計、２１は速度計２０を駆動する図示省略のスピ
ードメーターケーブルから速度を検出する検出
器、２２は検出器２１からの信号電流を増巾して
上記ソレノイド装置１４のコイル１５へ送る増幅
器で、２３は蓄電池である。したがつて、車輛の
速度は検出器２１によつて電気的に検出され、該
検出器２１からの信号電流は上記増幅器２２によ
つて増幅された後にコイル１５へ送られる。従つ
てプランジヤ１６は上記信号電流の強弱、即ち車
輛の速度に応じて進退変位され、同時にプランジ
ヤ１６と一体的な針状軸体１７も進退変位され
る。 Reference numeral 14 denotes a solenoid device provided in the flow control valve 4, and 15 and 16 denote a coil and a plunger constituting the solenoid device 14. The end of a needle-shaped shaft 17 is connected to the tip of the plunger 16, and the resilient force of a spring 19 acts on a flange 18 formed in the center of the plunger 16, so that the plunger 16 and the needle-shaped shaft 17 are normally positioned at the retreated end as shown in the figure. Reference numeral 20 denotes a speedometer, 21 denotes a detector that detects the speed from a speedometer cable (not shown) that drives the speedometer 20, 22 denotes an amplifier that amplifies the signal current from the detector 21 and sends it to the coil 15 of the solenoid device 14, and 23 denotes a storage battery. Thus, the speed of the vehicle is electrically detected by the detector 21, and the signal current from the detector 21 is amplified by the amplifier 22 before being sent to the coil 15. Therefore, the plunger 16 is displaced back and forth in response to the strength of the signal current, i.e., the speed of the vehicle, and at the same time, the needle-like shaft 17 integral with the plunger 16 is also displaced back and forth.

２４，２５はそれぞれ上記流量制御弁４の本体
２６内に形成した室で、上記針状軸体１７の進退
方向に直列に配設してあつて、一方の室２４内に
針状軸体１７の先端を突出させている。また、上
記室２４は上記流入口５と、室２５は流出口７と
連通させ、かつ室２４，２５間はオリフイス２７
により連通されており、前記針状軸体１７が前進
した際にその先端のテーパ部が上記オリフイス２
７内に嵌入し、該オリフイス２７内を流通する流
体の流量を制御できるようにしている。２８は上
記本体２６内の下方に形成した室、２９は該室２
８内に摺動自在に嵌合させたプランジヤ、３０は
上記室２８の開口端を閉塞するプラグで、室２８
は上記二室２４，２５と通路３１，３２でそれぞ
れ連通され、また該室２８は上記排出口１２と連
通されている。３３は上記プランジヤ２９とプラ
グ３０との間に介在させたばねで、その弾撥力に
より上記通路３１の開口端を閉塞させ、常時は通
路３１が上記排出口１２と連通するのを妨げてい
る。 Reference numerals 24 and 25 denote chambers formed in the main body 26 of the flow rate control valve 4, which are arranged in series in the forward and backward direction of the needle shaft 17. The tip is protruding. Further, the chamber 24 is communicated with the inlet port 5, the chamber 25 is communicated with the outlet port 7, and an orifice 27 is connected between the chambers 24 and 25.
When the needle-like shaft body 17 moves forward, the tapered portion at the tip thereof communicates with the orifice 2.
The orifice 27 is fitted into the orifice 27 so that the flow rate of the fluid flowing through the orifice 27 can be controlled. 28 is a chamber formed below in the main body 26; 29 is the chamber 2;
A plunger 8 is slidably fitted into the chamber 28, and a plug 30 closes the open end of the chamber 28.
are communicated with the two chambers 24 and 25 through passages 31 and 32, respectively, and the chamber 28 is communicated with the discharge port 12. A spring 33 is interposed between the plunger 29 and the plug 30, and its elastic force closes the open end of the passage 31, normally preventing the passage 31 from communicating with the discharge port 12.

さらに本実施例では、ポンプ１と動力舵取装置
８の供給口とを連通する流路の途中、すなわち上
記室２５内に、車速が所定値以上となつた際にそ
の動力舵取装置８の供給口を貯槽３に連通させる
流路切換弁３４を設けている。すなわち、上記室
２５内の右側には軸部にオリフイス３５を形成し
たバイパスバルブ３６を摺動自在に嵌合し、この
バルブ３６の右側に設けたばね３７の弾撥力によ
り通常はバルブ３６を室２５の中央部に設けたス
トツパリング３８に弾接させている。また上記本
体２６にはバイパス口３９を形成し、このバイパ
ス口３９は導管１０及び前記導管１０，１１を介
して貯槽３に連通させている。上記バイパス口３
９は、バルブ３６がストツパリング３８に当接し
た状態では室２５に、したがつて導管６を介して
動力舵取装置８の供給口に連通しているが、バル
ブ３６がばね３７に抗して所定距離以上右方に変
位された際には、そのバルブ３６の外周面により
上記動力舵取装置８の供給口との連通が遮断され
る。 Furthermore, in this embodiment, when the vehicle speed exceeds a predetermined value, the power steering device 8 A flow path switching valve 34 is provided to communicate the supply port with the storage tank 3. That is, a bypass valve 36 having an orifice 35 formed in its shaft is slidably fitted on the right side of the chamber 25, and the elastic force of a spring 37 provided on the right side of the valve 36 normally moves the valve 36 into the chamber. It is brought into elastic contact with a stopper ring 38 provided at the center of 25. Further, a bypass port 39 is formed in the main body 26, and this bypass port 39 is communicated with the storage tank 3 via the conduit 10 and the conduits 10 and 11. Bypass port 3 above
9 communicates with the chamber 25 when the valve 36 is in contact with the stopper ring 38, and therefore with the supply port of the power steering device 8 via the conduit 6, but when the valve 36 is in contact with the spring 37 When the valve 36 is displaced to the right by a predetermined distance or more, communication with the supply port of the power steering device 8 is cut off by the outer peripheral surface of the valve 36.

上記構成を有する実施例において、針状軸体１
７は前述したように車両の速度に応じて進退制御
され、速度が大きくなるに従つて針状軸体１７の
先端テーパ部が上記オリフイス２７内に進入す
る。 In the embodiment having the above configuration, the needle shaft body 1
7 is controlled to move forward or backward according to the speed of the vehicle, and as the speed increases, the tapered end of the needle shaft 17 enters the orifice 27.

従つて針状軸体１７が後退端に位置している車
輛の停止時又は低速走行時には、ポンプ１により
貯槽３内から導管２を介して流量制御弁４の室２
４内に圧送された流体は上記オリフイス２７を自
由に流通して室２５内に流入し、さらにバルブ３
６のオリフイス３５および導管６を介して動力舵
取装置８内に流入し、動力舵取装置８の機能を充
分に発揮させて低速時の操舵力を軽快なものとさ
せる。そしてこの状態では、上記バルブ３６のオ
リフイス３５を流通する流体の流量は多いのでこ
のオリフイス３５前後に圧力差が発生し、バルブ
３６はその圧力差によつて右方に変位されてバイ
パス口３９を閉じており、したがつて動力舵取装
置８の供給側通路が貯槽３に連通されてしまうと
いつたことはない。 Therefore, when the vehicle is stopped or running at low speed with the needle shaft body 17 located at the rearward end, the pump 1 pumps water from the storage tank 3 through the conduit 2 to the chamber 2 of the flow control valve 4.
The fluid pumped into the chamber 25 flows freely through the orifice 27, flows into the chamber 25, and then passes through the valve 3.
It flows into the power steering device 8 through the orifice 35 of No. 6 and the conduit 6, so that the function of the power steering device 8 is fully exhibited and the steering force at low speeds is light. In this state, since the flow rate of the fluid flowing through the orifice 35 of the valve 36 is large, a pressure difference is generated before and after the orifice 35, and the valve 36 is displaced to the right by the pressure difference, and the bypass port 39 is displaced. Therefore, there is no chance that the supply side passage of the power steering device 8 will be communicated with the storage tank 3.

かかる状態から車両の速度が増大すると、上記
針状軸体１７の先端のテーパ部が上記オリフイス
２７内を流通する流体の流量を減少させる。従つ
て、ポンプ１から流量制御弁４の室２４内に圧送
された流体は針状軸体１７とオリフイス２７とに
よつて流量を制限され、この流量を制限された流
体が上記動力舵取装置８に供給されるため動力舵
取装置の出力が低下して相対的に操舵力が大きく
なる。そして上記室２４内に供給された余剰の流
体はその圧力が高くなると、ばね３３の弾撥力及
び室２８内に通路３２を介して作用している室２
５内の流体圧力に抗してプランジヤ２９を後退さ
せ、流量制御弁４の排出口１２から導管１０，１
１を介して貯槽３へ還流する。 When the speed of the vehicle increases from this state, the tapered portion at the tip of the needle shaft 17 reduces the flow rate of fluid flowing through the orifice 27. Therefore, the flow rate of the fluid pumped from the pump 1 into the chamber 24 of the flow control valve 4 is restricted by the needle shaft 17 and the orifice 27, and the fluid with the restricted flow rate is transferred to the power steering device. 8, the output of the power steering device decreases and the steering force becomes relatively large. When the pressure of the excess fluid supplied into the chamber 24 increases, the elastic force of the spring 33 and the chamber 2 acting on the chamber 28 through the passage 32
The plunger 29 is retracted against the fluid pressure in the flow control valve 4, and the conduit 10,1 is discharged from the outlet 12 of the flow control valve 4.
1 to the storage tank 3.

そしてさらに車両の速度が増大して所定速度以
上の高速となると、上記オリフイス２７を流通す
る流体流量、したがつてバルブ３６のオリフイス
３５を流通する流体流量が一層減少し、そのオリ
フイス３５前後の圧力差が小さくなり、バルブ３
６がばね３７により左方に変位されて上記バイパ
ス口３９を開くので、動力舵取装置８の供給口は
導管６およびバイパス口３９を介して貯槽３に連
通される。この状態では舵取ハンドルを操作して
も、動力舵取装置８の供給側流路が貯槽３に連通
されているので油圧が上昇せず、したがつて動力
舵取装置８には補述動力は発生しないので操舵は
手動のみで行なわれることとなる。そしてその
際、パワーシリンダ内の吸込側となる室には貯槽
３から導管１１，１０，４０、バイパス口３９お
よび導管６を介して油が補充されるので負圧が発
生することはなく、その結果、操舵力をほぼ手動
舵取装置の操舵力と同程度の大きさにすることが
できる。 When the speed of the vehicle further increases to a high speed higher than a predetermined speed, the fluid flow rate flowing through the orifice 27, and therefore the fluid flow rate flowing through the orifice 35 of the valve 36, further decreases, and the pressure before and after the orifice 35 decreases. The difference becomes smaller and valve 3
6 is displaced to the left by the spring 37 to open the bypass port 39, so that the supply port of the power steering device 8 is communicated with the storage tank 3 via the conduit 6 and the bypass port 39. In this state, even if the steering wheel is operated, the supply side flow path of the power steering device 8 is connected to the storage tank 3, so the oil pressure does not increase, and therefore the power steering device 8 is supplied with supplementary power. Since this does not occur, steering must be performed only manually. At that time, the chamber on the suction side in the power cylinder is replenished with oil from the storage tank 3 through the conduits 11, 10, 40, the bypass port 39, and the conduit 6, so that no negative pressure is generated. As a result, the steering force can be made almost as large as the steering force of the manual steering device.

なお流量制御弁４は上記実施例に記載した構成
のものに限定されるものではなく、例えばエンジ
ンによつて駆動されるポンプの吐出油量を検出し
て動力舵取装置への供給量を減少させるタイプの
流量制御弁の使用も可能である。この場合、動力
舵取装置への供給量は厳密には車速に応じたもの
ではないが、実用上は車速に応じたものと云うこ
とができる。 Note that the flow rate control valve 4 is not limited to the configuration described in the above embodiment, and for example, the flow rate control valve 4 can detect the amount of oil discharged from a pump driven by the engine and reduce the amount of oil supplied to the power steering device. It is also possible to use a type of flow control valve. In this case, although the amount of power supplied to the power steering device does not strictly correspond to the vehicle speed, it can be said that it corresponds to the vehicle speed in practical terms.

本考案は以上に述べたように、流量制御弁によ
る動力舵取装置への供給量の増減を利用して動力
舵取装置の供給口と貯槽との連通を制御させるよ
うにしたものであつて、流路切換弁を構成するバ
イパスバルブを外部から作動させるための手段を
必要としないものであるから、その構成を極めて
簡単なものとすることができ、しかも上記バイパ
スバルブは、供給量が所定量まで減少したときの
進退位置でバイパス口を開口させるものであるか
ら、動力舵取装置の供給口を貯槽に連通させた際
の操舵力の変化を極めて小さいものとすることが
でき、かつ、高速時にも充分大きな操舵力を確保
することができるという効果が得られる。 As described above, the present invention is configured to control the communication between the supply port of the power steering device and the storage tank by using the increase/decrease in the amount of supply to the power steering device by the flow control valve. Since no means for externally operating the bypass valve constituting the flow path switching valve is required, the configuration can be made extremely simple, and the bypass valve described above does not require the supply amount to be adjusted to a certain level. Since the bypass port is opened at the advancing/retracting position when the power has decreased to a fixed amount, the change in steering force when the supply port of the power steering device is communicated with the storage tank can be made extremely small, and The effect is that a sufficiently large steering force can be secured even at high speeds.

そして、本考案においては、流路切換弁は流量
制御弁の下流側に設けられ、該流量制御弁による
制御流量の多寡に応じ進退制御されるバイパスバ
ルブを備え、その流量減少時に生ずるバイパスバ
ルブの変位によりバイパス口を開いてそのバイパ
スバルブの下流側、すなわち動力舵取装置の供給
口側を貯槽に連通させるようにしているため、従
来例、たとえばステアリングポンプと動力舵取装
置との流路の途中にスプール弁装置を介在させる
とともにこのスプール弁の一端に車速に応ずる作
動油圧を作用させ、車速の低減域においては非作
動の上記スプール弁を介してステアリングポンプ
の全油量を動力舵取装置に導き、中速域において
はスプール弁を押進させてステアリングポンプか
らの油量の一部を貯槽側へ分割還流させ、さらに
高速域においてはスプール弁を閉塞遮断させて全
油量を貯槽側へ還流させるようにしたものに比
べ、上記中速域においては動力舵取装置の負荷変
動により高圧時に貯槽側へ大油量が還流されてい
まい動力舵取装置への供給油量が不足して過大な
操舵力を強いられるようなことがなく、上記流量
制御弁の制御流量により負荷の変動にかかわりな
い動力舵取装置への必要流量が確保されるのみな
らず、高速域においては動力舵取装置の供給口側
が貯槽側と遮断され動力舵取装置の吸入側となる
供給口側が真空状態となつて極端な重い操舵力を
要求されるようなことがなく、上記バイパス口を
介し動力舵取装置の供給口側は貯槽と連通されて
手動舵取装置の操舵力とほぼ同程度の操舵力が得
られ運転者に違和感を与えることのない利点があ
る。 In the present invention, the flow path switching valve is provided on the downstream side of the flow rate control valve, and includes a bypass valve that is controlled to move forward or backward depending on the amount of flow rate controlled by the flow rate control valve. The bypass port is opened by displacement, and the downstream side of the bypass valve, that is, the supply port side of the power steering device, is communicated with the storage tank. A spool valve device is interposed in the middle, and hydraulic pressure corresponding to the vehicle speed is applied to one end of this spool valve, and in a region where the vehicle speed is reduced, the entire oil amount of the steering pump is controlled by the power steering device via the inactive spool valve. In the medium speed range, the spool valve is pushed forward to partially recirculate the oil from the steering pump to the storage tank, and in the high speed range, the spool valve is blocked and shut off to divert the entire oil amount to the storage tank. Compared to the case where the oil is returned to the storage tank in the medium speed range mentioned above, a large amount of oil is returned to the storage tank at high pressure due to load fluctuations of the power steering device, resulting in insufficient oil supply to the power steering device. Excessive steering force is not forced, and the flow rate controlled by the flow control valve not only ensures the required flow rate to the power steering device regardless of load fluctuations, but also ensures that the power steering device is not forced to use excessive steering force in the high-speed range. The supply port side of the device is isolated from the storage tank side, and the supply port side, which is the intake side of the power steering device, is not in a vacuum state and an extremely heavy steering force is not required, and power steering can be performed via the bypass port. The supply port side of the device is communicated with the storage tank, so that a steering force approximately equal to that of a manual steering device can be obtained, which has the advantage of not giving the driver a sense of discomfort.

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

図は本考案の一実施例を示し、要部を断面とし
た回路図である。 １……ポンプ、２，６……導管、３……貯槽、
４……流量制御弁、８……動力舵取装置、１０，
１１，４０……導管、３４……流路切換弁、３５
……オリフイス、３６……バイパスバルブ、３９
……バイパス口。 The figure shows an embodiment of the present invention, and is a circuit diagram showing a main part in cross section. 1... pump, 2, 6... conduit, 3... storage tank,
4...Flow control valve, 8...Power steering device, 10,
11, 40... Conduit, 34... Flow path switching valve, 35
... Orifice, 36 ... Bypass valve, 39
...Bypass port.

Claims (1)

【実用新案登録請求の範囲】[Scope of utility model registration request] 車速の増大に応じてポンプから動力舵取装置に
供給する圧油の流量を減少させる流量制御弁を備
えた動力舵取装置の操舵力制御装置において、上
記流量制御弁の下流側に、流量制御弁から動力舵
取装置へ供給される圧油の流通を許容するオリフ
イスを有し、このオリフイス前後に生じる圧力差
によつて進退制御されるバイパスバルブと、この
バイパスバルブの下流側と貯槽とを連通し、かつ
上記圧力差の減衰時に該バイパスバルブの変位に
応じて開口されるバイパス口とを備える流路切換
弁を備え、動力舵取装置への供給量が所定量以下
となつてときに上記供給口を貯槽に連通させるこ
とを特徴とする動力舵取装置の操舵力制御装置。 In a steering force control device for a power steering device that is equipped with a flow control valve that reduces the flow rate of pressure oil supplied from a pump to the power steering device in accordance with an increase in vehicle speed, a flow control device is provided downstream of the flow control valve. A bypass valve has an orifice that allows the flow of pressure oil supplied from the valve to the power steering device, and is controlled to move forward or backward based on the pressure difference generated before and after the orifice, and a storage tank is connected to the downstream side of the bypass valve. A flow path switching valve is provided with a bypass port that communicates with the bypass port and opens according to the displacement of the bypass valve when the pressure difference attenuates, and when the amount of supply to the power steering device becomes less than a predetermined amount. A steering force control device for a power steering device, characterized in that the supply port communicates with a storage tank.