JPH0215742Y2 - - Google Patents
Info
- Publication number
- JPH0215742Y2 JPH0215742Y2 JP1982180080U JP18008082U JPH0215742Y2 JP H0215742 Y2 JPH0215742 Y2 JP H0215742Y2 JP 1982180080 U JP1982180080 U JP 1982180080U JP 18008082 U JP18008082 U JP 18008082U JP H0215742 Y2 JPH0215742 Y2 JP H0215742Y2
- Authority
- JP
- Japan
- Prior art keywords
- oil
- pressure
- oil passage
- input shaft
- chamber
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000003921 oil Substances 0.000 description 115
- 239000010720 hydraulic oil Substances 0.000 description 15
- 238000010586 diagram Methods 0.000 description 5
- 239000011148 porous material Substances 0.000 description 5
- 230000007423 decrease Effects 0.000 description 4
- 238000011144 upstream manufacturing Methods 0.000 description 3
- 230000002093 peripheral effect Effects 0.000 description 2
- 230000006837 decompression Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
Description
【考案の詳細な説明】
本案は、ステアリングハンドルに連結されると
ともに円筒状ハウジング内に回転自在に挿入され
た入力軸と、同入力軸の端部が相対回転可能に挿
入される円筒部を一端に形成し且つ他端を操舵輪
に連結した出力軸と、上記入力軸と上記出力軸と
を連結するトーシヨンバーと、上記出力軸の円筒
部にその半径方向に沿つて穿設した貫通孔内に摺
動自在に嵌挿された反力ピストンと、同反力ピス
トンのハウジング側一端面と上記貫通孔の内面と
上記円筒状ハウジングの内面との間に形成された
第１のチヤンバーと、上記反力ピストンの他端面
と上記貫通孔の内面と上記入力軸の外周面との間
に形成された第２のチヤンバーとを具え、上記各
チヤンバーに供給される油圧の圧力差を車輌の走
行状態に応じて制御することにより上記反力ピス
トンの上記入力軸への押圧力を制御するように構
成したパワーステアリング装置において、前記反
力ピストンの一端面を前記円筒状ハウジングの内
面の曲率と略同一の曲率を有する曲面により形成
したことを特徴とするもので、その目的とする処
は、反力ピストンのハウジングに対するかじりや
フリクシヨンの増大を防止するパワーステアリン
グ装置を供する点にある。[Detailed description of the invention] The present invention includes an input shaft connected to a steering handle and rotatably inserted into a cylindrical housing, and a cylindrical part into which the end of the input shaft is inserted so as to be relatively rotatable. a torsion bar connecting the input shaft and the output shaft; and a through hole bored in the cylindrical portion of the output shaft along its radial direction. a first chamber formed between one end surface of the reaction piston on the housing side, an inner surface of the through hole, and an inner surface of the cylindrical housing; a second chamber formed between the other end surface of the power piston, the inner surface of the through hole, and the outer circumferential surface of the input shaft, and the pressure difference between the hydraulic pressures supplied to each chamber is adjusted to the running state of the vehicle. In the power steering device configured to control the pressing force of the reaction piston against the input shaft by controlling the force of the reaction piston according to It is characterized by being formed of a curved surface having a curvature, and its purpose is to provide a power steering device that prevents the reaction piston from galling or increasing friction with respect to the housing.
次に本案のパワーステアリング装置を第１，２
図に示す一実施例により説明すると、５が反力ピ
ストン、６が第１チヤンバー、６′が第２チヤン
バー、２１が円筒状ハウジング、３７が出力軸、
３７ａが出力軸３７の円筒部、３７ｂが出力軸３
７の貫通孔、３８がトーシヨンバー、３９が入力
軸で、同入力軸３９がステアリングハンドルに連
結されるとともに円筒状ハウジング２１内に回転
自在に挿入され、出力軸３７の一端に同入力軸３
９の端部を相対回転可能に挿入する円筒部３７ａ
が形成されるとともに同出力軸３７の他端が操舵
輪に連結され、トーシヨンバー３８が上記入力軸
３９と上記出力軸３７とを連結し、上記出力軸３
７の円筒部３７ａにその半径方向に沿つて貫通孔
３７ｂが穿設されるとともに同貫通孔３７ｂ内に
反力ピストン５が摺動自在に嵌挿され、第１チヤ
ンバー６が同反力ピストン５のハウジング２１側
一端面と上記貫通孔３７ｂの内面と上記ハウジン
グ２１の内面との間に形成され、第２チヤンバー
６′が上記反力ピストン５の他端面と上記貫通孔
３７ｂの内面と上記入力軸３９の外周面との間に
形成されている。そして反力ピストン５のハウジ
ング２１側一端面を円筒状ハウジング２１の内面
の曲率と略同一の曲率を有する曲面により形成し
ている。次に第１，２図に示すパワーステアリン
グ装置をさらに具体的に説明すると、１ａがエン
ジン、１ｂが同エンジン１ａにより駆動されるオ
イルポンプ、２が油路切換用ロータリー弁、３が
パワーシリンダ、４がタンク、５が上記油路切換
用ロータリー弁２の周りに設けた反力ピストン、
６が同ピストン５の背後に形成したチヤンバー、
８が上記オイルポンプ１ｂと上記油路切換弁２と
の間の高圧油路、９が上記油路切換弁２と上記タ
ンク４との低圧油路、７が同低圧油路９の途中に
設けた細孔、８′が上記高圧油路８の途中から上
記反力ピストン５のチヤンバー６へ延びた分岐油
路、１０が分岐油路８′の途中に介装した油路開
閉弁で、これを第３図により具体的に説明する
と、２１がバルブハウジング、２２がスプール、
２３がスプール２２を左方へ付勢するスプリン
グ、２４がソレノイド、２５が同ソレノイド２４
側のロツド、２５′が同ロツド２５の先端に設け
たスリツト、２６がプラグ、２７，２８がＯリン
グ、２９が上記バルブハウジング２１の溝に嵌挿
したスナツプリング、３０，３１，３２がチヤン
バー、３３が上記スプール２２に設けた油路で、
停車時及び低速走行時には、車速センサー（図示
せず）からの信号に基いてソレノイド２４に通電
され、ロツド２５を介しスプール２２が第３図の
位置から右方へ移動して、分岐油路８′が遮断さ
れ、また中・高速走行時には、車速センサーから
の信号に基いてソレノイド２４への通電が止ま
り、スプール２２がスプリング２３の反力により
左方へ移動して、圧力制御弁１１への油路が開放
されるようになつている。また、第１，２，４図
の１１が上記油路開閉弁１０の下流側に分岐油路
８′に介装した圧力制御弁で、これを同第２，４
図により具体的に説明すると、２１がバルブハウ
ジング、１３がスプール、１４が同スプール１３
を左方へ付勢するスプリング、１５が上記弁本体
１２に設けた作動油の入口、１６が上記バルブハ
ウジング２１に設けた作動油の出口、１７が上記
バルブハウジング２１に設けた排油孔で、同排油
孔１７は油路９′を介し上記低圧油路９が接続さ
れている。また１８ａ，１８ｂ，１８ｃ，１８ｄ
が上記スプール１３により形成されたバルブハウ
ジング２１内のチヤンバー、１９ａが上記スプー
ル１３に設けた連通孔、１９ｂが同スプール１３
に設けた細孔で、チヤンバー１８ｃが低圧油路
９′を介して細孔７より下流のタンク４側低圧油
路９に、チヤンバー１８ｄが低圧油路９″を介し
て細孔７よりも上流の油路切換弁２側低圧油路９
に、それぞれ接続されている。次に前記油路切換
用ロータリー弁２を第１図により具体的に説明す
ると、３５が前記バルブハウジング２１に設けた
ラツクサポート、３６がラツク、３７が同ラツク
３６に噛合したピニオン、３９が入力軸、３８が
同入力軸４９と上記ピニオン３７とを連結するト
ーシヨンバー、４０が上記入力軸３９の周りに取
付けたバルブボデイ、４１，４２，４３が同バル
ブボデイ４０の外周面に設けた環状溝、４４が上
記環状溝４１から半径方向内方へ延びた複数の油
路、４５が上記バルブボデイ４０の内周面に軸方
向に沿い設けた複数の油路で、同各油路４５は上
記環状溝４２に連通している。また同各油路４５
の間には同様の油路（図示せず）があり、これが
上記環状溝４１と上記環状溝４３とを連通してい
る。また４６が上記入力軸３９を半径方向に貫通
した複数の油路、４７，４８が上記環状溝４２，
４３からバルブケーシング２１壁を貫通して前記
シリンダ３へ延びた油路、４９が上記トーシヨン
バー３８と上記入力軸３９との間に形成されたチ
ヤンバーで、オイルポンプ１ｂからの圧油が高圧
油路８→環状溝４１→油路４４→油路４５→油路
４６→チヤンバー４９→低圧油路９→タンク４→
オイルポンプ１ｂに循環するように、またハンド
ル（図示せず）を右に切つて、入力軸３９を右に
回転すると、入力軸３９の油路４６が軸方向油路
４５の間に設けた軸方向油路（図示せず）に連通
し、オイルポンプ１ｂからの圧油が高圧油路８→
環状溝４１→油路４４→油路４５→環状溝４２→
油路４７を経てシリンダ３の一方へ送られて、同
シリンダ３が右方へ作動する一方、シリンダ３の
他方の油が油路４８→環状溝４３→油路４４（図
示せず）→軸方向油路４５の間に設けた軸方向油
路→油路４６→チヤンバー４９→低圧油路９を経
てタンク４へ戻されるように、またハンドルを左
に切つて、入力軸３９を左に回転すると、入力軸
３９の油路４６が軸方向油路４５に連通し、オイ
ルポンプ１ｂからの圧油が高圧油路８→環状溝４
１→油路４４（図示せず）→軸方向油路４５の間
に設けた軸方向油路→環状溝４３→油路４８を経
てシリンダ３の他方へ送られて、同シリンダ３が
左方へ作動する一方、シリンダ３の一方の油が油
路４７→環状溝４２→軸方向油路４５→油路４６
→チヤンバー４９→低圧油路９を経てタンク４へ
戻されるようになつている。また第２図の５０，
５１はオイルシール、５２，５３はベアリング、
５４は前記圧力制御弁１１の軸線上に設けたキヤ
ツプ、５５が同キヤツプ５４側のパイプ５４′に
設けた穴である。なお同穴５５はパイプ５４′内
に圧力の高まりが発生しないようにするために設
けた油逃し穴で、圧力制御弁１１のスプール１３
とパイプ５４′との間には隙間があり、特に設け
る必要はないが、圧力制御弁１１のスプール１３
が上昇して上記隙間が閉ざされたときに問題にな
るので、設けているにすぎない。また５６が前記
ピニオン３７のラジアル荷重を支承するジヤーナ
ル軸受、５７が同ジヤーナル軸受５６の下側に形
成したチヤンバーで、同チヤンバー５７が油路５
８と開閉弁１０のチヤンバー３３（第３図参照）
と油路３３とチヤンバー３１とを介して低圧油路
９′に連通している。なお同チヤンバー５７は開
閉弁１０内を介さずに低圧油路９′に連通させて
もよい。 Next, the power steering device of the present invention is installed in the first and second stages.
To explain with one embodiment shown in the figure, 5 is a reaction piston, 6 is a first chamber, 6' is a second chamber, 21 is a cylindrical housing, 37 is an output shaft,
37a is the cylindrical part of the output shaft 37, 37b is the output shaft 3
7 is a through hole, 38 is a torsion bar, 39 is an input shaft, the input shaft 39 is connected to the steering handle and rotatably inserted into the cylindrical housing 21, and the input shaft 3 is connected to one end of the output shaft 37.
cylindrical portion 37a into which the end portion of 9 is relatively rotatably inserted;
is formed, and the other end of the output shaft 37 is connected to the steering wheel, a torsion bar 38 connects the input shaft 39 and the output shaft 37, and the output shaft 37 is connected to the steering wheel.
A through hole 37b is bored along the radial direction of the cylindrical portion 37a of No. 7, and the reaction piston 5 is slidably inserted into the through hole 37b, and the first chamber 6 is inserted into the reaction piston 5. A second chamber 6' is formed between the other end surface of the reaction piston 5, the inner surface of the through hole 37b, and the input side. It is formed between the shaft 39 and the outer circumferential surface of the shaft 39. One end surface of the reaction piston 5 on the housing 21 side is formed by a curved surface having substantially the same curvature as the curvature of the inner surface of the cylindrical housing 21. Next, to explain the power steering device shown in FIGS. 1 and 2 in more detail, 1a is an engine, 1b is an oil pump driven by the engine 1a, 2 is a rotary valve for oil passage switching, 3 is a power cylinder, 4 is a tank, 5 is a reaction piston provided around the oil passage switching rotary valve 2,
6 is a chamber formed behind the same piston 5,
8 is a high pressure oil passage between the oil pump 1b and the oil passage switching valve 2, 9 is a low pressure oil passage between the oil passage switching valve 2 and the tank 4, and 7 is provided in the middle of the low pressure oil passage 9. 8' is a branch oil passage extending from the middle of the high-pressure oil passage 8 to the chamber 6 of the reaction piston 5; 10 is an oil passage opening/closing valve interposed in the middle of the branch oil passage 8'; To explain this in detail with reference to FIG. 3, 21 is a valve housing, 22 is a spool,
23 is a spring that urges the spool 22 to the left, 24 is a solenoid, and 25 is the solenoid 24.
25' is a slit provided at the tip of the rod 25, 26 is a plug, 27 and 28 are O-rings, 29 is a snap ring inserted into the groove of the valve housing 21, 30, 31, and 32 are chambers, 33 is an oil path provided in the spool 22,
When the vehicle is stopped or traveling at low speed, the solenoid 24 is energized based on a signal from a vehicle speed sensor (not shown), and the spool 22 moves to the right from the position shown in FIG. ' is shut off, and when driving at medium or high speeds, the energization to the solenoid 24 is stopped based on the signal from the vehicle speed sensor, and the spool 22 is moved to the left by the reaction force of the spring 23, causing the pressure control valve 11 to be turned off. The oil passage is now open. Reference numeral 11 in FIGS. 1, 2, and 4 is a pressure control valve installed in the branch oil passage 8' on the downstream side of the oil passage opening/closing valve 10.
To explain in detail with the drawings, 21 is a valve housing, 13 is a spool, and 14 is the same spool 13.
15 is a hydraulic oil inlet provided in the valve body 12, 16 is a hydraulic oil outlet provided in the valve housing 21, and 17 is an oil drain hole provided in the valve housing 21. The oil drain hole 17 is connected to the low pressure oil passage 9 via an oil passage 9'. Also 18a, 18b, 18c, 18d
is a chamber in the valve housing 21 formed by the spool 13, 19a is a communication hole provided in the spool 13, and 19b is a chamber formed by the spool 13.
The chamber 18c is connected to the low pressure oil path 9 on the tank 4 side downstream of the hole 7 via the low pressure oil path 9', and the chamber 18d is connected to the low pressure oil path 9 upstream of the hole 7 via the low pressure oil path 9''. Oil passage switching valve 2 side low pressure oil passage 9
are connected to each other. Next, to explain the oil passage switching rotary valve 2 in detail with reference to FIG. 1, 35 is a rack support provided on the valve housing 21, 36 is a rack, 37 is a pinion meshed with the rack 36, and 39 is an input. a shaft; 38 is a torsion bar connecting the input shaft 49 and the pinion 37; 40 is a valve body attached around the input shaft 39; 41, 42, 43 are annular grooves provided on the outer peripheral surface of the valve body 40; denotes a plurality of oil passages extending radially inward from the annular groove 41; 45 denotes a plurality of oil passages provided along the axial direction on the inner peripheral surface of the valve body 40; each oil passage 45 is connected to the annular groove 42; is connected to. In addition, each oil passage 45
There is a similar oil passage (not shown) between them, which communicates the annular groove 41 and the annular groove 43. Further, 46 indicates a plurality of oil passages passing through the input shaft 39 in the radial direction, 47 and 48 indicate the annular groove 42,
An oil passage 43 extends to the cylinder 3 through the wall of the valve casing 21, and 49 is a chamber formed between the torsion bar 38 and the input shaft 39, through which pressure oil from the oil pump 1b is passed through a high-pressure oil passage. 8 → Annular groove 41 → Oil passage 44 → Oil passage 45 → Oil passage 46 → Chamber 49 → Low pressure oil passage 9 → Tank 4 →
When the input shaft 39 is rotated to the right by turning the handle (not shown) to the right so that the oil circulates to the oil pump 1b, the oil passage 46 of the input shaft 39 is connected to the shaft provided between the axial oil passages 45. It communicates with a directional oil passage (not shown), and the pressure oil from the oil pump 1b flows through the high pressure oil passage 8→
Annular groove 41 → Oil passage 44 → Oil passage 45 → Annular groove 42 →
The oil from the other cylinder 3 is sent to one side of the cylinder 3 through the oil passage 47 and moves to the right, while the oil from the other cylinder 3 is sent from the oil passage 48 to the annular groove 43 to the oil passage 44 (not shown) to the shaft. Turn the handle to the left and rotate the input shaft 39 to the left so that the oil returns to the tank 4 via the axial oil path provided between the directional oil paths 45 → oil path 46 → chamber 49 → low pressure oil path 9. Then, the oil passage 46 of the input shaft 39 communicates with the axial oil passage 45, and the pressure oil from the oil pump 1b flows from the high pressure oil passage 8 to the annular groove 4.
1 → oil passage 44 (not shown) → axial oil passage provided between the axial oil passage 45 → annular groove 43 → oil is sent to the other side of the cylinder 3 via the oil passage 48, and the cylinder 3 is sent to the left side. At the same time, the oil on one side of the cylinder 3 flows from oil passage 47 → annular groove 42 → axial oil passage 45 → oil passage 46.
-> Chamber 49 -> Low pressure oil passage 9 and then returned to tank 4. Also, 50 in Figure 2,
51 is an oil seal, 52 and 53 are bearings,
54 is a cap provided on the axis of the pressure control valve 11, and 55 is a hole provided in the pipe 54' on the side of the cap 54. Note that the hole 55 is an oil relief hole provided to prevent pressure from increasing inside the pipe 54', and
There is a gap between the pipe 54' and the spool 13 of the pressure control valve 11, although it is not necessary to provide a gap.
This is only provided because it will become a problem when the above-mentioned gap is closed due to rising. Further, 56 is a journal bearing that supports the radial load of the pinion 37, and 57 is a chamber formed on the lower side of the journal bearing 56.
8 and the chamber 33 of the on-off valve 10 (see Figure 3)
It communicates with the low pressure oil passage 9' via the oil passage 33 and the chamber 31. Note that the chamber 57 may be communicated with the low pressure oil passage 9' without going through the on-off valve 10.
次に前記パワーステアリング装置の作用を説明
する。エンジン１ａにより駆動されるオイルポン
プ１ｂの吐出流量はエンジン回転数に応じて第５
図のように変化する。即ち、停車時から低速走行
時にかけては急速に増加し、中速走行時には急速
に減少し、高速走行時には減少した一定値に保持
される（なおこのオイルポンプ１ｂについて必要
ならば実願昭57−4939号（実開昭58−109585号）
明細書を参照されたい）。上記のようにオイルポ
ンプ１ｂから吐出される作動油の流量が急速に増
加する停車時から低速走行時にかけては、分岐油
路８′の途中に設けた油路開閉弁１０が閉じられ
ている。そのためオイルポンプ１ｂから吐出され
た作動油の全てが油路切換用ロータリー弁２を介
しパワーシリンダ３へ導かれて、油路切換用ロー
タリー弁２の両側の反力ピストン５に反力が生せ
ず、同油路切換用ロータリー弁２によるかじ取り
操作が軽快に行なわれる。一方、上記のようにオ
イルポンプ１ｂから吐出される作動油の流量が急
速に減少して一定値に保持される中速走行時から
高速走行時にかけては、分岐油路８′の途中に設
けた油路開閉弁１０が開かれる。そのためオイル
ポンプ１ｂから吐出された作動油の一部が油路開
閉弁１０を経て圧力制御弁１１へ導かれる。この
作動油は走行状態の如何により圧力が80Kg／cm2〜
60Kg／cm2程度の間で変化しており、上限値付近の
作動油が入口１５からチヤンバー１８ａ，１８ｂ
へ入つて（細孔１４を通過する流量よりも多くの
作動油がチヤンバー１８ａ，１８ｂへ入つて）、
チヤンバー１８ａ，１８ｂとチヤンバー１８ｃと
の差圧が、１８ａ，１８ｂ＞１８ｃになつたとき
には、同差圧より、スプール１３がスプリング１
４に抗し右方へ移動し（第２図では上昇し）、入
口１５の開口面積を減少させ、流量を絞る（第４
図参照）し、下限値付近の作動油が入口１５から
チヤンバー１８ａ内へ入つたときには、スプール
１３がスプリング１４により左方へ移動し、入口
１５の開口面積を増大させて、流量をふやす。つ
まり、分岐油路８′を流れる作動油の圧力如何に
かかわらず出口１６から出る作動油の圧力（流
量）をほぼ一定に保持する。一方、細孔７よりも
上流の油路切換用ロータリー弁２側低圧回路９の
作動油の圧力は、２〜４Kg／cm2程度の範囲ではあ
るが、第６図のように中速走行時から高速走行時
にかけて急速に減少して、高速走行時には一定値
に保持される。そのためチヤンバー１８ｄ内の圧
力が中速走行時よりも高速走行時に低下して、ス
プリング１４のスプール押し戻し力が相対的に大
きくなり、その分だけチヤンバー１８ａ，１８ｂ
内の圧力が上昇する。即ち、チヤンバー１８ａ，
１８ｂ内の圧力をPa、チヤンバー１８ｃ内の圧
力をPc、チヤンバー１８ｄ内の圧力をPd、Ａを
π／４（D2−d2）、Ｄをスプール１３の大径、ｄを
スプール１３の小径（チヤンバー１８ｄの直径）、
ａ＝π／４d2とすると、チヤンバー１８ａの圧力Pa
は、
Pa＝Ｒ／Ａ＋Pc−Pdａ／Ａ
で表わされ、（Ｒ／Ａ＋Pc）がほぼ一定のため、Pd
が小さくなると、Paが大きくなる。結果的にチ
ヤンバー１８ａ，１８ｂの圧力を油路開閉弁１０
とで車速に応じコントロールできる。なお反力ピ
ストン５の反力とは、入力軸（ピニオン）３７と
入力軸３９との間に配設された反力ピストン５の
反力増大側チヤンバーに供給される油圧と、反力
減少側チヤンバーに供給される油圧との差により
発生している力であり、トーシヨンバー３８の作
用力とともに入力軸３９に作用する抵抗となる
力、即ち、入力軸３９を操作するのに必要な力で
ある。また細孔７は、入力軸３９に形成されてい
るが、その上流側に位置する減圧通路４９には、
パワーシリンダ３から排出される低圧の作動油が
供給されており、低圧油路９″、及び圧力制御弁
１１のパイロツト油圧室１８ｄには、減圧通路４
９と実質的に同一の油圧が作用している。この油
圧は、ポンプ吐出量に対応しており、結果的に極
く低圧（２〜４Kg／cm2）になる。また上記細孔７
の下流側に位置する低圧油路９には、略大気圧の
油圧が作用している。また圧力制御弁１１は、高
圧油路８の作動油を略一定の制御油圧として反力
ピストン５の反力増大側チヤンバーに供給せしめ
るとともに、パイロツト油圧室には、上記減圧通
路４９の油圧、即ち、ポンプ流量に応じた油圧が
供給され、結果としてエンジン回転数によく対応
した油圧が反力ピストン５の反力増大側チヤンバ
ーに供給されて、適切な反力が得られる。また入
力軸３９はバルブハウジング（ハルブボデイ）４
０に対してベアリング５２により支持され、オイ
ルシール５０により油密に保持されている。この
ベアリング５２の直下には、低圧油路９９が配設
されており、オイルシール５０に対して作用する
圧力が低く、オイルシール５０と入力軸３９との
間に生じる摩擦力が小さくなる。従つて操作感、
及びオイルシール５０の耐久性が向上する。 Next, the operation of the power steering device will be explained. The discharge flow rate of the oil pump 1b driven by the engine 1a varies according to the engine speed.
Changes as shown in the figure. That is, it increases rapidly from a stop to when driving at low speeds, decreases rapidly when driving at medium speeds, and is maintained at a reduced constant value when driving at high speeds. No. 4939 (Utility Model No. 58-109585)
Please refer to the specification). As described above, from when the vehicle is stopped to when the vehicle is running at low speed, when the flow rate of the hydraulic oil discharged from the oil pump 1b increases rapidly, the oil passage opening/closing valve 10 provided in the middle of the branch oil passage 8' is closed. Therefore, all of the hydraulic oil discharged from the oil pump 1b is guided to the power cylinder 3 via the oil passage switching rotary valve 2, and a reaction force is generated in the reaction pistons 5 on both sides of the oil passage switching rotary valve 2. First, the steering operation using the oil passage switching rotary valve 2 is performed easily. On the other hand, as mentioned above, when the flow rate of the hydraulic oil discharged from the oil pump 1b rapidly decreases and is maintained at a constant value from medium speed to high speed driving, the branch oil passage 8' is provided in the middle. The oil passage opening/closing valve 10 is opened. Therefore, a part of the hydraulic oil discharged from the oil pump 1b is guided to the pressure control valve 11 via the oil passage opening/closing valve 10. The pressure of this hydraulic oil varies from 80Kg/cm 2 to 80Kg/cm 2 depending on the driving condition.
It changes between about 60Kg/cm2, and the hydraulic oil near the upper limit flows from the inlet 15 to the chambers 18a and 18b.
(more hydraulic fluid enters the chambers 18a, 18b than the flow rate passing through the pores 14),
When the differential pressure between the chambers 18a, 18b and the chamber 18c becomes 18a, 18b>18c, the spool 13 is moved by the spring 1 due to the differential pressure.
4 (rises in Figure 2), reduces the opening area of the inlet 15, and throttles the flow rate (No. 4).
When hydraulic oil near the lower limit enters the chamber 18a from the inlet 15, the spool 13 is moved to the left by the spring 14, increasing the opening area of the inlet 15 and increasing the flow rate. In other words, the pressure (flow rate) of the hydraulic oil exiting from the outlet 16 is maintained substantially constant regardless of the pressure of the hydraulic oil flowing through the branch oil passage 8'. On the other hand, the pressure of the hydraulic oil in the low pressure circuit 9 on the side of the rotary valve 2 for oil path switching upstream of the pore 7 is in the range of about 2 to 4 kg/ cm2 , but as shown in Fig. 6, when running at medium speed, It rapidly decreases from 1 to 300 mph when driving at high speeds, and is maintained at a constant value during high speed driving. Therefore, the pressure inside the chamber 18d is lower during high-speed driving than during medium-speed driving, and the force pushing back the spool of the spring 14 becomes relatively large.
The pressure inside increases. That is, the chamber 18a,
The pressure in the chamber 18b is Pa, the pressure in the chamber 18c is Pc, the pressure in the chamber 18d is Pd, A is π/4 (D 2 - d 2 ), D is the large diameter of the spool 13, and d is the small diameter of the spool 13. (diameter of chamber 18d),
When a=π/ 4d2 , the pressure Pa in the chamber 18a is expressed as Pa=R/A+Pc-Pda/A, and since (R/A+Pc) is almost constant, as Pd decreases, Pa increases. . As a result, the pressure in the chambers 18a, 18b is reduced to the oil passage opening/closing valve 10.
It can be controlled according to the vehicle speed. Note that the reaction force of the reaction piston 5 refers to the hydraulic pressure supplied to the reaction force increasing side chamber of the reaction force piston 5 disposed between the input shaft (pinion) 37 and the input shaft 39, and the reaction force decreasing side. This is a force generated due to the difference between the hydraulic pressure supplied to the chamber and the force acting as a resistance that acts on the input shaft 39 together with the acting force of the torsion bar 38, that is, the force necessary to operate the input shaft 39. . Further, although the pore 7 is formed in the input shaft 39, the decompression passage 49 located upstream thereof has a
Low-pressure hydraulic oil discharged from the power cylinder 3 is supplied, and the low-pressure oil passage 9'' and the pilot hydraulic chamber 18d of the pressure control valve 11 are supplied with the pressure reducing passage 4.
Substantially the same hydraulic pressure as 9 is acting. This oil pressure corresponds to the pump discharge amount, resulting in an extremely low pressure (2 to 4 Kg/cm 2 ). In addition, the above pore 7
Hydraulic pressure at approximately atmospheric pressure acts on the low-pressure oil passage 9 located downstream of. Further, the pressure control valve 11 supplies the hydraulic oil in the high pressure oil passage 8 as a substantially constant control oil pressure to the reaction force increasing side chamber of the reaction force piston 5, and also supplies the oil pressure in the pressure reduction passage 49 to the pilot oil pressure chamber. , a hydraulic pressure corresponding to the pump flow rate is supplied, and as a result, a hydraulic pressure corresponding to the engine rotational speed is supplied to the reaction force increasing side chamber of the reaction force piston 5, and an appropriate reaction force is obtained. In addition, the input shaft 39 is a valve housing (hull body) 4
0 by a bearing 52, and is kept oil-tight by an oil seal 50. A low-pressure oil passage 99 is disposed directly below this bearing 52, so that the pressure acting on the oil seal 50 is low, and the frictional force generated between the oil seal 50 and the input shaft 39 is reduced. Therefore, the operational feeling,
And the durability of the oil seal 50 is improved.
前記油路開閉弁１０の作動時（圧力制御弁１１
への作動油の供給をカツトしているとき）、また
は前記オイルポンプ１ａからギヤへの供給油量が
多いとき（チヤンバー１８ｃ細孔１９ｂ低圧油路
９′，９が接続しているとき）には、分岐油路
８′チヤンバー６の圧力が低い。一方、チヤンバ
ー４９の圧力が細孔７により絞られているため、
分岐油路８′チヤンバー６の圧力よりも高くなつ
ている。この状態では、反力ピストン５が第１図
に示すように油圧反力によりハウジング２１の
内面に押しつけられている。このとき操舵する
と、反力ピストン５のハウジング側端部がハウジ
ング２１の内面を摺動し、反力ピストン５の端部
形状によつてはハウジング２１の内面をかじつた
り、フリクシヨンを増大させたりする。 When the oil passage opening/closing valve 10 is activated (pressure control valve 11
(when the supply of hydraulic oil is cut off to , the pressure in the branch oil passage 8' chamber 6 is low. On the other hand, since the pressure in the chamber 49 is restricted by the pores 7,
The pressure in the branch oil passage 8' chamber 6 is higher than that in the chamber 6. In this state, the reaction piston 5 is pressed against the inner surface of the housing 21 by hydraulic reaction force, as shown in FIG. When steering at this time, the housing side end of the reaction piston 5 slides on the inner surface of the housing 21, and depending on the shape of the end of the reaction piston 5, it may bite the inner surface of the housing 21 or increase friction. do.
本案のパワーステアリング装置は前記のように
ステアリングハンドルに連結されるとともに円筒
状ハウジング内に回転自在に挿入された入力軸
と、同入力軸の端部が相対回転可能に挿入される
円筒部を一端に形成し且つ他端を操舵輪に連結し
た出力軸と、上記入力軸と上記出力軸とを連結す
るトーシヨンバーと、上記出力軸の円筒部にその
半径方向に沿つて穿設した貫通孔内に摺動自在に
嵌挿された反力ピストンと、同反力ピストンのハ
ウジング側一端面と上記貫通孔の内面と上記円筒
状ハウジングの内面との間に形成された第１のチ
ヤンバーと、上記反力ピストンの他端面と上記貫
通孔の内面と上記入力軸の外周面との間に形成さ
れた第２のチヤンバーとを具え、上記各チヤンバ
ーに供給される油圧の圧力差を車輌の走行状態に
応じて制御することにより上記反力ピストンの上
記入力軸への押圧力を制御するように構成したパ
ワーステアリング装置において、前記反力ピスト
ンの一端面を前記円筒状ハウジングの内面の曲率
と略同一の曲率を有する曲面により形成したの
で、反力ピストンが円筒状ハウジングの内面に押
し付けられるとき（第１チヤンバーの圧力が第２
チヤンバーの圧力よりも低く、入力軸に反力が作
用していないとき）、ピストンのハウジング側一
端面を円筒状ハウジングの内面に対して滑らかに
摺動させることができて、反力ピストンの円筒状
ハウジングに対応するかじり等を防止できる。 As described above, the power steering device of the present invention includes an input shaft connected to a steering handle and rotatably inserted into a cylindrical housing, and a cylindrical part into which the end of the input shaft is relatively rotatably inserted. a torsion bar connecting the input shaft and the output shaft; and a through hole bored in the cylindrical portion of the output shaft along its radial direction. a first chamber formed between one end surface of the reaction piston on the housing side, an inner surface of the through hole, and an inner surface of the cylindrical housing; a second chamber formed between the other end surface of the power piston, the inner surface of the through hole, and the outer circumferential surface of the input shaft, and the pressure difference between the hydraulic pressures supplied to each chamber is adjusted to the running state of the vehicle. In the power steering device configured to control the pressing force of the reaction piston against the input shaft by controlling the force of the reaction piston according to Since it is formed by a curved surface having a curvature, when the reaction piston is pressed against the inner surface of the cylindrical housing (the pressure in the first chamber is
(when the pressure is lower than the pressure in the chamber and no reaction force is acting on the input shaft), one end surface of the housing side of the piston can slide smoothly against the inner surface of the cylindrical housing, and the cylinder of the reaction piston It is possible to prevent galling, etc., due to the shape of the housing.
また上記のように反力ピストンの一端面を円筒
状ハウジングの内面の曲率と略同一の曲率を有す
る曲面により形成しているので、両者の接触面積
が増大でき、力の集中を回避できて、耐摩耗性を
向上できる上に、仮令両者が磨耗したとしても、
略同一の曲率なので、当初の曲面に保持できて、
操作性等の低下を防止できる。 In addition, as mentioned above, since one end surface of the reaction piston is formed by a curved surface having approximately the same curvature as the curvature of the inner surface of the cylindrical housing, the contact area between the two can be increased and concentration of force can be avoided. Not only can wear resistance be improved, but even if both parts are worn out,
Since the curvature is almost the same, the original curved surface can be maintained,
Deterioration in operability etc. can be prevented.
また上記の構成により、反力ピストンが外側
（円筒状ハウジング側）へ押圧されたときの力を
直接円筒状ハウジングで受けることが可能で、リ
テーナ等の部品を不要にできて、構造を簡潔化で
きる上に、パワーステアリング装置の全体をコン
パクト化できる効果がある。 In addition, the above configuration allows the cylindrical housing to directly receive the force when the reaction piston is pushed outward (towards the cylindrical housing), eliminating the need for retainers and other parts, simplifying the structure. In addition, it has the effect of making the entire power steering device more compact.
第１図は本案に係るパワーステアリング装置
の一実施例を示す縦断側面図、第１図，は反
力ピストン部の横断平面図、第２図はその油圧回
路図、第３図は油路開閉弁の一実施例を示す縦断
側面図、第４図は圧力制御弁の一実施例を示す縦
断側面図、第５図はオイルポンプの吐出流量特性
を示す説明図、第６図はオリフイスの上流圧を示
す説明図、第７図は圧力制御弁のチヤンバー（出
入口側圧力室）の圧力を示す説明図、第８図は圧
力−入力トルク特性を示す説明図である。
５……反力ピストン、６……第１チヤンバー、
６′……第２チヤンバー、２１……円筒状ハウジ
ング、３７……出力軸、３７ａ……出力軸３７の
円筒部、３７ｂ……貫通孔、３８……トーシヨン
バー、３９……入力軸。
Fig. 1 is a longitudinal side view showing an embodiment of the power steering device according to the present invention, Fig. 1 is a cross-sectional plan view of the reaction piston section, Fig. 2 is its hydraulic circuit diagram, and Fig. 3 is an oil passage opening/closing diagram. FIG. 4 is a longitudinal side view showing an embodiment of the valve, FIG. 4 is a longitudinal side view showing an embodiment of the pressure control valve, FIG. 5 is an explanatory diagram showing the discharge flow rate characteristics of the oil pump, and FIG. FIG. 7 is an explanatory diagram showing the pressure in the chamber (inlet/outlet side pressure chamber) of the pressure control valve, and FIG. 8 is an explanatory diagram showing the pressure-input torque characteristic. 5... Reaction piston, 6... First chamber,
6'...Second chamber, 21...Cylindrical housing, 37...Output shaft, 37a...Cylindrical portion of output shaft 37, 37b...Through hole, 38...Torsion bar, 39...Input shaft.
Claims (1)
筒状ハウジング内に回転自在に挿入された入力軸
と、同入力軸の端部が相対回転可能に挿入される
円筒部を一端に形成し且つ他端を操舵輪に連結し
た出力軸と、上記入力軸と上記出力軸とを連結す
るトーシヨンバーと、上記出力軸の円筒部にその
半径方向に沿つて穿設した貫通孔内に摺動自在に
嵌挿された反力ピストンと、同反力ピストンのハ
ウジング側一端面と上記貫通孔の内面と上記円筒
状ハウジングの内面との間に形成された第１のチ
ヤンバーと、上記反力ピストンの他端面と上記貫
通孔の内面と上記入力軸の外周面との間に形成さ
れた第２のチヤンバーとを具え、上記各チヤンバ
ーに供給される油圧の圧力差を車輌の走行状態に
応じて制御することにより上記反力ピストンの上
記入力軸への押圧力を制御するように構成したパ
ワーステアリング装置において、前記反力ピスト
ンの一端面を前記円筒状ハウジングの内面の曲率
と略同一の曲率を有する曲面により形成したこと
を特徴とするパワーステアリング装置。 An input shaft connected to a steering handle and rotatably inserted into a cylindrical housing; one end formed with a cylindrical part into which the end of the input shaft is relatively rotatably inserted; and the other end connected to a steering wheel. a torsion bar that connects the connected output shaft, the input shaft and the output shaft, and a reaction force that is slidably inserted into a through hole bored in the cylindrical portion of the output shaft along its radial direction. a first chamber formed between a piston, one end surface of the reaction piston on the housing side, an inner surface of the through hole, and an inner surface of the cylindrical housing; a second chamber formed between an inner surface and an outer circumferential surface of the input shaft, and the reaction piston is controlled by controlling the pressure difference between the hydraulic pressures supplied to each chamber according to the running state of the vehicle. In the power steering device configured to control the pressing force on the input shaft, one end surface of the reaction piston is formed by a curved surface having substantially the same curvature as the curvature of the inner surface of the cylindrical housing. Power steering device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18008082U JPS5983666U (en) | 1982-11-30 | 1982-11-30 | power steering device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18008082U JPS5983666U (en) | 1982-11-30 | 1982-11-30 | power steering device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5983666U JPS5983666U (en) | 1984-06-06 |
| JPH0215742Y2 true JPH0215742Y2 (en) | 1990-04-26 |
Family
ID=30390552
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18008082U Granted JPS5983666U (en) | 1982-11-30 | 1982-11-30 | power steering device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5983666U (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0754054Y2 (en) * | 1985-07-31 | 1995-12-13 | 三菱自動車工業株式会社 | Power steering device |
| JPH0728050Y2 (en) * | 1985-07-31 | 1995-06-28 | 三菱自動車工業株式会社 | Power steering device |
| JPH0728049Y2 (en) * | 1985-07-31 | 1995-06-28 | 三菱自動車工業株式会社 | Power steering device |
| JPH0728051Y2 (en) * | 1985-07-31 | 1995-06-28 | 三菱自動車工業株式会社 | Power steering device |
| JPH0728052Y2 (en) * | 1985-11-19 | 1995-06-28 | 三菱自動車工業株式会社 | Power steering device |
-
1982
- 1982-11-30 JP JP18008082U patent/JPS5983666U/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5983666U (en) | 1984-06-06 |
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