JPS61181711A - Vehicle level adjusting device - Google Patents
Vehicle level adjusting deviceInfo
- Publication number
- JPS61181711A JPS61181711A JP2116785A JP2116785A JPS61181711A JP S61181711 A JPS61181711 A JP S61181711A JP 2116785 A JP2116785 A JP 2116785A JP 2116785 A JP2116785 A JP 2116785A JP S61181711 A JPS61181711 A JP S61181711A
- Authority
- JP
- Japan
- Prior art keywords
- vehicle
- pressure
- vehicle height
- fluid
- rear sections
- 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.)
- Pending
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G17/00—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load
- B60G17/015—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Vehicle Body Suspensions (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は車体を前後同時に車高調整するための車高調整
システムに関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vehicle height adjustment system for simultaneously adjusting the height of a vehicle body in the front and rear directions.
従来の車高調整システムとして例えば牙7図に示すもの
がある。同図において、(1)は油圧源、(21(3)
はこの油圧源(1)からの圧:油を、フロント側のサス
ペンション(41(51およびリヤ側のサスペンション
(61(71に切換供給する切換バルブである。As a conventional vehicle height adjustment system, there is one shown in FIG. 7, for example. In the figure, (1) is a hydraulic power source, (21 (3)
is a switching valve that selectively supplies pressure/oil from this oil pressure source (1) to the front suspension (41 (51) and the rear suspension (61 (71)).
(81(91は各サスペンション(4) (51および
(6) (71に圧油を供給する際に開かれろチェック
バルブ、(10)旧)は各サスペンション(4H51お
よび(6) (7)の圧油を切換バルブ(2) (31
を通じて排出する際に、その圧油を絞りながら流出させ
るオリフィス、(121(131(141<151は各
サスペンション(4)(5)(6) (7)の油室に連
設したアキュムレータ、Q61はリザーバタンク、α甜
マ油圧源(1)とリザーバタンク(16)とを結ぶ油路
に入れたアンロードバルブである。(81 (91) is a check valve that is opened when supplying pressure oil to each suspension (4) (51 and (6) (71), (10) old) is a check valve for each suspension (4H51 and (6) (7)) Oil switching valve (2) (31
(121 (131 (141 < 151 is an accumulator connected to the oil chamber of each suspension (4) (5) (6) (7), Q61 is This is an unload valve installed in an oil path connecting the reservoir tank, α-sweet oil pressure source (1) and the reservoir tank (16).
かかる従来の車高調整システムでは、車高を上昇させる
場合に、切換バルブ(21(31を一方に切り換えると
、油圧源(1)からの圧油がこれらの切換バルブ(2+
(31およびチェックバルブ(81(91でそれぞれ通
じて各サスペンション+41 (51および(6)(力
に供給され、これらの各サスペンション(41(51お
よび(6) (7)が伸長することによって、車高が上
昇する。一方、車高を下げる場合には各切換バルブを他
方に切り換えると、各サスペンション(41(51およ
び(61(7)内の圧油がオリフィスf10)(11)
および切換バルブ(2+ (31をそれぞれ介してニリ
ザーバタンク(161071に排出される。このため、
各サスペンション(41(51および(61(7)は収
縮し、車高が低下する。In such conventional vehicle height adjustment systems, when the vehicle height is raised, when the switching valves (21 (31) are switched to one side, pressure oil from the hydraulic source (1) is transferred to these switching valves (2+).
(31 and check valves (81 (91) respectively pass through each suspension +41 (51 and (6)) (force is supplied to each suspension (41 (51 and (6)) (7) by extending the car On the other hand, when lowering the vehicle height, by switching each switching valve to the other side, the pressure oil in each suspension (41 (51) and (61 (7)) flows through orifice f10 (11).
and switching valves (2+ (31) and are discharged to the ni reservoir tank (161071). Therefore,
Each suspension (41 (51) and (61 (7)) contracts, and the vehicle height decreases.
しかしながら、かかる従来の車高調整システムでは、車
高を上昇させようとする際、車体の重量カフロント側と
リヤ側とでは異っているので、切換バルブ(21(3)
を同時に開くと、重量が軽い側のサスペンション(41
(51または(61(7]が先に伸長して車体に傾きを
生じる。つまり、フロント側およびリヤ側が同時かつ等
量ずつ伸長することにはならない。また、油圧源(1)
がポンプである場合には、重量が重い側のサスペンショ
ンかう軽い側のサスペンションへの圧油の逆流カ生じ、
重量が重い側のサスペンションはその逆流によって一度
下がった後に上昇する。つまり、各サスペンションをフ
ロント側およびリヤ側の片方ずつ上昇させることになり
、これを車両走行中に実施する場合には操安上極めて危
険、であるという問題があった。However, in such conventional vehicle height adjustment systems, when trying to raise the vehicle height, the weight of the vehicle body is different between the front side and the rear side, so the switching valve (21(3)
If you open both at the same time, the suspension on the lighter side (41
(51 or (61 (7)) expands first, causing the vehicle body to tilt. In other words, the front and rear sides do not extend at the same time and by the same amount. Also, the hydraulic source (1)
If it is a pump, pressure oil will flow back from the suspension on the heavier side to the suspension on the lighter side.
The suspension on the heavier side lowers and then rises due to the reverse flow. In other words, each suspension has to be raised one at a time on the front side and one on the rear side, which poses a problem in that it is extremely dangerous in terms of driving safety if this is done while the vehicle is running.
一方、かかる問題を解決するために、油圧源(11と各
切換バルブ(2)(31とに通じる油路中に70−デイ
バイダを設けて、これにより圧油を1対1に分流させて
、車体の傾きを生じないように車高を上昇させるものが
提案されている。しかしながら、かかるフローディバイ
ダは製作費が高くつくとともに、システムを大形化して
しまう。On the other hand, in order to solve this problem, a 70-divider is provided in the oil path leading to the hydraulic source (11) and each switching valve (2) (31), thereby dividing the pressure oil one to one, A flow divider has been proposed that raises the vehicle height to prevent the vehicle body from tilting.However, such a flow divider is expensive to manufacture and increases the size of the system.
また1、f−1図゛に示したものと同様のチェックバル
ブ(81(9)やオリフィスαO)σDを必要とし、構
成がさらに複雑化するという問題があった。In addition, a check valve (81(9) and orifice αO) σD similar to that shown in FIG.
本発明はかかる従来の問題点を解決するものであり、フ
ロント側およびリヤ側の各切換バルブを交互かつ断続的
に開閉することによって、フロント側およびリヤ側の各
サスペンションを同時的かつ等量ずつ昇降させるように
した車高調整システムを提供することを目的とする。The present invention solves these conventional problems, and by opening and closing the front and rear switching valves alternately and intermittently, the front and rear suspensions are simultaneously and equally controlled. The purpose of the present invention is to provide a vehicle height adjustment system that raises and lowers the vehicle height.
本発明にかかる車高調整システムは、圧力センサによっ
て車両のフロント側およびリヤ側の負荷圧力を検出し、
この検出出力にもとづいて、コントローラが車高上昇時
および車高下降時におけるそれぞれ流体供給量および流
体排出量に見合った時間幅のパルスを演算して出力し、
このパルスを各切換バルブに交互かつ断続的に供給する
ようになして、フロント側およびリヤ側の各サスペンシ
ョンの上昇量および下降量を等速、等量制御する構成と
したものである。The vehicle height adjustment system according to the present invention detects the load pressure on the front side and rear side of the vehicle using a pressure sensor,
Based on this detection output, the controller calculates and outputs pulses with a time width commensurate with the fluid supply amount and fluid discharge amount when the vehicle height is raised and when the vehicle height is lowered, respectively.
This pulse is alternately and intermittently supplied to each switching valve to control the amount of rise and fall of each of the front and rear suspensions at a constant speed and by the same amount.
この発明ではコントローラは、車両のフロント側および
リヤ側の各圧力センサからの各サスペンションの内圧デ
ータにもとづいて、その油圧系に特有な単位時間当りの
流体供給量および単位時間当りの流体排出量を求め、こ
うして求めた流体供給量および流体排出量を条件として
、各サスペンションの伸長量または収縮量を等量かつ断
続的に行わしめるに必要な供給時間または排出時間、つ
まり各切換バルブに供給する電力パルスの時間幅を演算
して、この結果を切換バルブに交互に人力する。こうす
れば、流体の流量と時間の積で求められる流体圧力を上
記各サスペンションに対し等量ずつ給排できることにな
り、各サスペンションの昇降量はフロント側およびリヤ
側でバランスすることになる。In this invention, the controller calculates the amount of fluid supplied per unit time and the amount of fluid discharged per unit time that is specific to the hydraulic system, based on the internal pressure data of each suspension from each pressure sensor on the front side and rear side of the vehicle. Determine the supply or discharge time required to extend or contract each suspension equally and intermittently, subject to the thus determined fluid supply and fluid discharge amounts, that is, the power supplied to each switching valve. The time width of the pulse is calculated and the result is alternately input manually to the switching valve. In this way, equal amounts of fluid pressure determined by the product of fluid flow rate and time can be supplied to and discharged from each of the suspensions, and the amount of elevation of each suspension is balanced between the front and rear sides.
牙1図は本発明にかかる車高調整システムの接続図であ
り、矛7図に示したものと同一の構成部分には同一符号
を付してその重複する説明を省略する。矛1図において
、1181(19は車両のフロント側の左右の負荷圧力
を検出する圧力センサ、C’Ce (21+は車両のリ
ヤ側の左右の負荷圧力を検出する圧力センサで、この実
施例では各サスペンション(41(51(61(71の
油室内圧力を検出する構成となっている。また、のは上
記各圧カセンサα&〜(21)の出力にもとづいてフロ
ント側およびリヤ側の上記切換バルブ(21(31を制
御するコントローラであり、これが例えば牙2図のよう
な構成および以下の作用となっている。Figure 1 is a connection diagram of the vehicle height adjustment system according to the present invention, and the same components as those shown in Figure 7 are designated by the same reference numerals and redundant explanation thereof will be omitted. In Figure 1, 1181 (19 is a pressure sensor that detects the left and right load pressure on the front side of the vehicle, C'Ce (21+ is a pressure sensor that detects the left and right load pressure on the rear side of the vehicle, and in this embodiment, It is configured to detect the pressure in the oil chamber of each suspension (41 (51) (61 (71). Also, based on the output of each pressure sensor α & ~ (21), the front side and rear side switching valves (21 (This is a controller that controls 31, and has a configuration as shown in Fig. 2, for example, and the following functions.
牙2図において、Gυは圧力センサQ81 Hによって
検出した負荷圧力Pa 、 Pbの平均値(Pα十P、
6)/2を求める平均値回路、船は圧力センサ(イ)1
21)により検出した負荷圧力Pc、Pdの平均値CP
c+Pd)/2を求める平均値回路で、これらの各平均
値回路(3Il(3zから出力されたフロント側および
リヤ側の平均値の負荷圧力が、牙3図(α)(h)に示
す制御マツプをメモリ内に有する演算回路031 (3
41に人力されろ。演算回路(ト)(2)では各平均値
(Pα+PA ) /2 。In Fig. 2, Gυ is the average value of the load pressures Pa and Pb detected by the pressure sensor Q81H (Pα0P,
6) Average value circuit to calculate /2, ship uses pressure sensor (a) 1
21) Average value CP of load pressure Pc and Pd detected by
c+Pd)/2, and the load pressure of the average value of the front side and rear side output from each of these average value circuits (3Il(3z) is controlled as shown in Fig. 3 (α) (h). Arithmetic circuit 031 (3
Let 41 help you. In the arithmetic circuit (g) (2), each average value (Pα+PA)/2.
(Pc+Pd)/2に応じた単位時間当りの流体のサス
ペンション(4) (51および(6) (7)に対す
る供給量Qt。The supply amount Qt of fluid to the suspension (4) (51 and (6) (7) per unit time according to (Pc+Pd)/2.
Qxおよび単位時間当りの流体のサスペンションからの
排出i q、 、 q、を上゛・記マツプから求める。Qx and the discharge of fluid from the suspension per unit time i q, , q are determined from the map described above.
C35+(36)はパルス電流発生回路であり、牙4図
(α)(b)に示すように、これらは各負荷圧力に対応
した流体の供給量に反比例する時間幅T/、TJのパル
ス電流および牙5図(α)(6)に示すように流体の排
出量に反比例する時間幅T3.’r=のパルス電流を出
カスる。これらのパルス電流は、演算回路f331 (
34)に入力される車高上昇指令信号S/、車高下降指
令信号Sλに応じて切り換えられるスイッチ回路C37
]を介して切換バルブ(21(31に人力される。つま
り、上記供給量に逆比例しておよび上記排出量に逆比例
して、切換バルブ(2)(3)の開時間を制御する。な
お、この場合において、QzTl−:QλT2゜qlT
l−=qlTコとなるように、それぞれパルス幅c時間
)T/、TJ、 TJ、 Tμを決め、さらにこれらの
パルス幅Tt 、 TJ 、 TJ 、 Te7が例え
ば゛数10m5ec程度に十分小さく設定する。また、
T/とTJおよびTJとTaはそれぞれ同時に生じない
ようにする。こうすることにより、2つの切換バルブ(
2)(3)が同時に開くことによるサスペンション(4
1(5)および(6) (71の一側から他側への流体
の移動を防止でき上記のような゛車体の傾きを防止でき
る。C35+ (36) is a pulse current generation circuit, and as shown in Figure 4 (α) and (b), these generate pulse currents with time widths T/ and TJ that are inversely proportional to the amount of fluid supplied corresponding to each load pressure. and the time width T3, which is inversely proportional to the amount of fluid discharged, as shown in Figure 5 (α) (6). Outputs a pulse current of 'r=. These pulse currents are processed by the arithmetic circuit f331 (
34) A switch circuit C37 that is switched according to the vehicle height increase command signal S/ and vehicle height decrease command signal Sλ input to
) through the switching valves (21 (31); that is, the opening times of the switching valves (2) and (3) are controlled in inverse proportion to the said supply amount and inversely proportional to the said discharge amount. In addition, in this case, QzTl−:QλT2゜qlT
Determine the pulse widths (c time) T/, TJ, TJ, and Tμ so that l-=qlT, and further set these pulse widths Tt, TJ, TJ, and Te7 to be sufficiently small, for example, about several tens of m5ec. . Also,
T/ and TJ and TJ and Ta should not occur simultaneously. By doing this, the two switching valves (
2) Suspension (4) due to (3) opening at the same time
1(5) and (6) (Movement of fluid from one side of 71 to the other side can be prevented, and the above-mentioned tilting of the vehicle body can be prevented.
なお、車高上昇時における上記切換バルブ(2+(3)
の開閉制御において、油圧源(11がポンプである場合
には、各切換バルブ(2++31が同時に閉じた場合に
、アンロードバルブαnが閉じられているので、ポンプ
リリーフ状態となる。そこで、これを避けるためには、
できるだけ切換バルブ(2)(3)が同時に閉じること
のないようにする必要があり、上記切換バルブ(21f
31が同時に開くことによる上記欠点をも考慮して、切
換バルブ(2+ +3)が同時に閉じる時間T!を牙6
図に示すようにできるだけ微小値に設定する。また、か
かる微小な時間Tjにおいて油圧源(IJと各切換バル
ブ(21(31とを結ぶ油路の圧力が上昇するのを防止
するため、この油路の一部をゴムホースなどの可撓性油
路とすることにより、上記圧力上昇をこれに吸収させる
ことができ、これによりポンプリリーフを完全に抑える
ことが可能になる。なお、上記サスペンション(4)〜
(7)に対する流体圧の供給および排出の速度は上記パ
ルス電流のデユーティ比を選択することにより任意に設
定できる。In addition, when the vehicle height is raised, the above switching valve (2+(3)
In the opening/closing control of the hydraulic source (11), if the switching valves (2++31) are closed at the same time, the unload valve αn is closed and the pump is in a relief state. In order to avoid
It is necessary to prevent the switching valves (2) and (3) from closing at the same time as much as possible.
Taking into consideration the above-mentioned disadvantages caused by opening of valves 31 and 31 at the same time, the time T for switching valves (2+ +3) to close simultaneously! Fang 6
Set it to the smallest possible value as shown in the figure. In addition, in order to prevent the pressure in the oil path connecting the hydraulic source (IJ and each switching valve 21 (31) from increasing during this minute time Tj, a part of this oil path is connected to a flexible oil such as a rubber hose. By forming a passageway, the pressure increase can be absorbed by this, thereby making it possible to completely suppress pump relief.In addition, the suspension (4) to
The speed of fluid pressure supply and discharge for (7) can be arbitrarily set by selecting the duty ratio of the pulse current.
また、上記は油圧サスペンションについて述べたがエア
ーサスペンレヨンによる車高調整にっいても同様である
。Further, although the above description has been made regarding the hydraulic suspension, the same applies to vehicle height adjustment using the air suspension system.
また、上記負荷圧力P/とPdが等しい場合には、油圧
源(1)の供給特性がQ/=Qλ、ql=9.2となる
ので、T/−TJ、TJ−T4tとして上記制御を行え
ば良いことになる。In addition, when the load pressure P/ and Pd are equal, the supply characteristics of the hydraulic source (1) are Q/=Qλ, ql=9.2, so the above control is performed as T/-TJ, TJ-T4t. It will be a good thing if you do it.
以上述べてきたように、本発明によれば圧力センサによ
り車両のフロント側およびリヤ側の負荷圧力を検出し、
この検出出力にもとづいてコントローラにより、上記負
荷圧力に応じて予め設定した開時間だけ各切換バルブを
交互かつ断続的に制御するようにしたことによって、車
体の昇降を車体のフロント側またはリヤ側への異常な傾
きな〈実施できるものである。かくして、車両走行中の
車高調整も操安性を害することなく実行できるものであ
る。As described above, according to the present invention, the load pressure on the front side and rear side of the vehicle is detected by the pressure sensor,
Based on this detection output, the controller alternately and intermittently controls each switching valve for a preset opening time according to the load pressure, so that the vehicle body can be raised or lowered to the front or rear side of the vehicle. There is an abnormal slope of 〈something that can be implemented. In this way, the vehicle height can be adjusted while the vehicle is running without impairing steering stability.
牙1図は本発明にかかる車高調整システムの接続図、矛
2図はコントローラのブロック回路図、矛3図はコント
ローラ内のメモリに記憶させた9荷圧力に対する流体の
供給量および排出惰力制御マツプ、牙4図は車高上昇時
のフロント側およびリヤ側の切換バルブに対するパルス
電流波形図、牙5図は同じく車高下降時のパルス電流波
形図、牙6図はポンプリリーフ防止のための車高上昇時
におけるパルス電流波形図、之・7図は従来の車高調整
システムの接続図である。
(1)・・・流体圧源、(2) (31・・・切換バル
ブ、(4)(5+f(il(7i ” サスヘ:/ ’
i E ン、α81(191(201(2+1−−−圧
力センサ、(221−φ・コントローラ。
第3図
(a) (b)
第4図
第5図
第6図Figure 1 shows the connection diagram of the vehicle height adjustment system according to the present invention, Figure 2 shows the block circuit diagram of the controller, and Figure 3 shows the amount of fluid supplied and the discharge inertia stored in the memory of the controller. Control map, Fig. 4 is a pulse current waveform diagram for the front and rear switching valves when the vehicle height is rising, Fig. 5 is a pulse current waveform diagram when the vehicle height is lowered, and Fig. 6 is for pump relief prevention. Figure 7 is a connection diagram of a conventional vehicle height adjustment system. (1)...Fluid pressure source, (2) (31...Switching valve, (4)(5+f(il(7i) ” Sushe:/'
i E N, α81(191(201(2+1---Pressure sensor, (221-φ・controller. Fig. 3 (a) (b) Fig. 4 Fig. 5 Fig. 6
Claims (1)
とを結ぶ流体通路に、これらの各サスペンションに対す
る流体の給排を行うように切り換えられるフロント側お
よびリヤ側の切換バルブを接続した車高調整システムに
おいて、車両のフロント側およびリヤ側の負荷圧力をそ
れぞれ各別に検出する圧力センサと、上記各圧力センサ
によつて検出した車高上昇時における負荷圧力に対する
単位時間当りの流体供給量および車高下降時における上
記負荷圧力に対する単位時間当りの流体排出量のそれぞ
れに見合つた時間幅のパルスを、上記各切換バルブに対
して交互かつ断続的に供給するコントローラとを設けた
ことを特徴とする車高調整システム。In a vehicle height adjustment system in which front and rear switching valves that are switched to supply and discharge fluid to each suspension are connected to a fluid passage connecting a fluid pressure source and each of the front and rear suspensions. , a pressure sensor that separately detects the load pressure on the front side and rear side of the vehicle, and the amount of fluid supplied per unit time with respect to the load pressure detected by each of the above pressure sensors when the vehicle height is rising and when the vehicle height is falling. and a controller that alternately and intermittently supplies each of the switching valves with a pulse having a time width commensurate with the amount of fluid discharged per unit time with respect to the load pressure. system.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2116785A JPS61181711A (en) | 1985-02-06 | 1985-02-06 | Vehicle level adjusting device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2116785A JPS61181711A (en) | 1985-02-06 | 1985-02-06 | Vehicle level adjusting device |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS61181711A true JPS61181711A (en) | 1986-08-14 |
Family
ID=12047353
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2116785A Pending JPS61181711A (en) | 1985-02-06 | 1985-02-06 | Vehicle level adjusting device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS61181711A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63106130A (en) * | 1986-10-24 | 1988-05-11 | Mazda Motor Corp | Vehicle suspension device |
EP0315163A2 (en) * | 1987-11-06 | 1989-05-10 | Pfister GmbH | Method for optimizing the driving characteristics of a vehicle |
JPH0495806U (en) * | 1991-01-18 | 1992-08-19 | ||
WO1998002321A1 (en) * | 1996-07-11 | 1998-01-22 | Daimler-Benz Aktiengesellschaft | Ground clearance-regulated, air-suspended axle aggregate, for example for monospace private cars |
-
1985
- 1985-02-06 JP JP2116785A patent/JPS61181711A/en active Pending
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63106130A (en) * | 1986-10-24 | 1988-05-11 | Mazda Motor Corp | Vehicle suspension device |
EP0315163A2 (en) * | 1987-11-06 | 1989-05-10 | Pfister GmbH | Method for optimizing the driving characteristics of a vehicle |
JPH0495806U (en) * | 1991-01-18 | 1992-08-19 | ||
WO1998002321A1 (en) * | 1996-07-11 | 1998-01-22 | Daimler-Benz Aktiengesellschaft | Ground clearance-regulated, air-suspended axle aggregate, for example for monospace private cars |
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