JP2587379Y2 - Horsepower control device for variable displacement pump - Google Patents
Horsepower control device for variable displacement pumpInfo
- Publication number
- JP2587379Y2 JP2587379Y2 JP1992043584U JP4358492U JP2587379Y2 JP 2587379 Y2 JP2587379 Y2 JP 2587379Y2 JP 1992043584 U JP1992043584 U JP 1992043584U JP 4358492 U JP4358492 U JP 4358492U JP 2587379 Y2 JP2587379 Y2 JP 2587379Y2
- Authority
- JP
- Japan
- Prior art keywords
- pump
- horsepower
- pressure
- secondary throttle
- throttle valve
- 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 - Fee Related
Links
Landscapes
- Details And Applications Of Rotary Liquid Pumps (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本考案は、１台の原動機で同時に
可変容量ポンプを含む複数台の油圧ポンプを駆動する場
合に使用される馬力制御装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a horsepower control device used when a plurality of hydraulic pumps including a variable displacement pump are simultaneously driven by one prime mover.
【０００２】[0002]
【従来の技術】従来、図１に示すように、１台の原動機
ａで固定容量ポンプまたは可変容量ポンプの主ポンプｂ
と、少なくとも１台の可変容量ポンプの従ポンプｃとを
伝動機構ｄを介して同時に駆動することは行なわれてお
り、この場合、原動機ａからの入力動力を有効に利用す
るために、主ポンプｂの吐出量を使用していないときは
２次絞り弁ｅを作動させて例えば２台の従ポンプｃ，ｃ
の設定馬力を上げ、また主ポンプｂを使用したときには
従ポンプｃ，ｃの設定馬力を下げるようにしている。可
変容量形の従ポンプｃは、例えば斜板のようなポンプ容
量を可変する構成と、斜板等を動かすための油圧を導入
する馬力設定部ｆを備えており、該馬力設定部ｆに導入
される圧力の大小によりポンプ容量（吐出量）を変更し
て吐出圧と吐出量の積で表されるポンプ馬力を変更する
ようになっている。図１の場合、従ポンプｃの馬力設定
の変更のために自己吐出圧を直接に馬力設定部ｆに導入
しないで、該従ポンプｃの吐出回路ｇからタンクｈへ１
次絞りｉと２次絞りｊを有する制御回路ｋを設け、該１
次絞りｉと２次絞りｊの間の制御回路ｋを該従ポンプｃ
の馬力設定部ｆに接続し、該２次絞りｊを該主ポンプｂ
の吐出圧の高まりで閉じる２次絞り弁ｅに構成して該従
ポンプｃの馬力設定を変更するようになっており、この
構成により、主ポンプｂが無負荷あるいは低い圧力で運
転されているときには、２次絞り弁ｅが制御回路ｋをタ
ンクｈへ繋ぐ開の状態になり、各従ポンプｃの馬力設定
部ｆには１次絞りｉと２次絞りの作用で吐出回路ｇの圧
力よりも減圧された圧力が作用し、各従ポンプｃのポン
プ容量を増大させてその設定馬力を増大させ、主ポンプ
ｂで生じる余剰馬力を従ポンプｃに於いて消費して原動
機ａの出力トルクを有効に利用することができる。ま
た、主ポンプｂが最高吐出圧で運転されているときは、
２次絞り弁ｌが制御回路ｋのタンクｈへの連通を閉じる
ので、制御回路ｋの圧力は各従ポンプｃの吐出圧と同圧
になり、各従ポンプｃの馬力設定部ｆはそのポンプ容量
を減少させて設定馬力を減少させ、原動機ａが過負荷に
ならないように制御する。この場合、主ポンプｂは固定
容量形でもよく、従ポンプｃは２台以上であってもよ
い。2. Description of the Related Art Conventionally, as shown in FIG. 1, a single prime mover a has a main pump b of a fixed displacement pump or a variable displacement pump.
And at least one slave pump c of at least one variable displacement pump are simultaneously driven via a transmission mechanism d. In this case, in order to effectively use the input power from the prime mover a, the main pump When the discharge amount of b is not used, the secondary throttle valve e is operated, for example, to set two sub-pumps c and c.
, And when the main pump b is used, the set horsepower of the secondary pumps c and c is decreased. The variable displacement type sub-pump c has a configuration such as a swash plate that varies the pump capacity, and a horsepower setting unit f that introduces hydraulic pressure for moving the swash plate and the like. The pump horsepower represented by the product of the discharge pressure and the discharge amount is changed by changing the pump capacity (discharge amount) according to the magnitude of the applied pressure. In the case of FIG. 1, the self-discharge pressure is not directly introduced into the horsepower setting unit f to change the horsepower setting of the slave pump c, but the discharge pressure g from the discharge circuit g of the slave pump c to the tank h.
A control circuit k having a secondary aperture i and a secondary aperture j is provided.
The control circuit k between the secondary throttle i and the secondary throttle j is connected to the slave pump c.
And the secondary throttle j is connected to the main pump b.
The secondary throttle valve e, which closes when the discharge pressure increases, changes the horsepower setting of the sub-pump c. With this configuration, the main pump b is operated at no load or at a low pressure. At this time, the secondary throttle valve e is in an open state connecting the control circuit k to the tank h, and the horsepower setting section f of each slave pump c is controlled by the pressure of the discharge circuit g by the action of the primary throttle i and the secondary throttle. The reduced pressure also acts, increasing the pump capacity of each slave pump c to increase its set horsepower, and consuming the excess horsepower generated by the main pump b in the slave pump c to reduce the output torque of the prime mover a. It can be used effectively. When the main pump b is operated at the maximum discharge pressure,
Since the secondary throttle valve 1 closes the communication of the control circuit k to the tank h, the pressure of the control circuit k becomes the same as the discharge pressure of each of the sub-pumps c, and the horsepower setting section f of each of the sub-pumps c The set horsepower is reduced by reducing the capacity, and control is performed so that the prime mover a is not overloaded. In this case, the main pump b may be of a fixed displacement type, and the number of slave pumps c may be two or more.
【０００３】[0003]
【考案が解決しようとする課題】図１の構成では、主ポ
ンプｂの使用馬力に応じて従ポンプｃ，ｃの設定馬力を
変えて原動機ａの出力を有効に利用できるが、ポンプの
運転状況以外では馬力を有効に利用できない不都合があ
る。例えば、原動機ａが、その回転数が低い場合に出力
トルクが小さく、回転数が高い場合に出力トルクが大き
くなるような特性を持つ場合、図１の構成では原動機ａ
の特性に合わせて従ポンプｃ，ｃの馬力設定を変更でき
ないので、有効に原動機ａの出力を利用できない。ま
た、ポンプｂ，ｃが実機に搭載されており、実機が特定
の作業を設定馬力で行ない、他の作業をその設定馬力よ
りも高い或いは低い馬力で行なうような作業形態に応じ
て馬力を設定し、原動機ａの出力を有効利用することも
出来ない。In the configuration shown in FIG. 1, the output of the prime mover a can be used effectively by changing the set horsepower of the sub-pumps c and c according to the used horsepower of the main pump b. Other than that, there is a disadvantage that horsepower cannot be used effectively. For example, when the prime mover a has such a characteristic that the output torque is small when the rotation speed is low and the output torque is large when the rotation speed is high, in the configuration of FIG.
The output of the prime mover a cannot be used effectively because the horsepower setting of the slave pumps c and c cannot be changed in accordance with the characteristics of Further, the pumps b and c are mounted on the actual machine, and the actual machine performs a specific operation at a set horsepower and sets the horsepower according to a work mode in which the other work is performed at a horsepower higher or lower than the set horsepower. However, the output of the prime mover a cannot be used effectively.
【０００４】本考案は、主ポンプの使用馬力に対応する
のみならず必要に応じて従ポンプの設定馬力を自動的に
変更できる馬力設定装置を提供することを目的とするも
のである。SUMMARY OF THE INVENTION It is an object of the present invention to provide a horsepower setting device which can automatically change a set horsepower of a sub-pump as required, in addition to a use horsepower of a main pump.
【０００５】[0005]
【課題を解決するための手段】本考案では、１台の原動
機により同時に１台の主ポンプと少なくとも１台の可変
容量形の従ポンプを駆動し、該従ポンプの吐出回路から
タンクへ１次絞りと２次絞りを有する制御回路を設け、
該１次絞りと２次絞りの間の制御回路を該従ポンプの馬
力設定部に接続し、該２次絞りを該主ポンプの吐出圧の
高まりで閉じる２次絞り弁に構成して該従ポンプの馬力
設定を変更するようにした装置に於いて、該２次絞り弁
に該主ポンプの吐出圧が作用する第１受圧面と、外部パ
イロット圧が作用する第２受圧面を有するパイロットピ
ストンを連設して該２次絞り弁の作動を制御することに
より、上記の目的を達成するようにした。According to the present invention, one prime mover drives one main pump and at least one variable displacement type secondary pump at the same time, and the primary pump from the discharge circuit of the secondary pump to the tank. A control circuit having a diaphragm and a secondary diaphragm is provided,
A control circuit between the primary throttle and the secondary throttle is connected to a horsepower setting section of the slave pump, and the secondary throttle is configured as a secondary throttle valve which closes at an increase in the discharge pressure of the master pump to form the slave throttle. In a device for changing the horsepower setting of a pump, a pilot piston having a first pressure receiving surface on which a discharge pressure of the main pump acts on the secondary throttle valve and a second pressure receiving surface on which an external pilot pressure acts. The above-described object is achieved by controlling the operation of the secondary throttle valve by connecting the control valves.
【０００６】[0006]
【作用】パイロットピストンに外部パイロット圧を作用
させないときは、主ポンプの吐出圧の高低により２次絞
り弁が開閉し、従ポンプの馬力設定部に作用する制御回
路の圧力が変更されて図１に示す従来のものと同様に主
ポンプの吐出圧に応じて従ポンプの馬力設定が行なわれ
る。外部パイロット圧をパイロットピストンに作用させ
ると、２次絞り弁が開いているときでも強制的にこれを
閉じて従ポンプの馬力設定部に作用する制御回路の圧力
を高くすることが出来、従ポンプの設定馬力を低く変更
出来る。そのため、前記のように原動機の出力特性が、
その回転数の低いときに出力トルクが小さく、回転数の
高いときに出力トルクが大きくなる変化をする場合、原
動機の低下する馬力だけパイロットピストンの第２受圧
面に外部パイロット圧を作用させて従ポンプの馬力設定
を下げておき、回転数が上がった時にこの外部パイロッ
ト圧を抜いて馬力設定を上げれば、原動機の馬力を有効
に利用できる。When the external pilot pressure is not applied to the pilot piston, the secondary throttle valve opens and closes depending on the level of the discharge pressure of the main pump, and the pressure of the control circuit acting on the horsepower setting section of the slave pump is changed. The horsepower of the sub-pump is set in accordance with the discharge pressure of the main pump, as in the prior art shown in FIG. When the external pilot pressure is applied to the pilot piston, even when the secondary throttle valve is open, the secondary throttle valve is forcibly closed and the pressure of the control circuit acting on the horsepower setting section of the secondary pump can be increased. Can be changed to lower horsepower. Therefore, as described above, the output characteristics of the prime mover
When the output torque is small when the rotation speed is low, and the output torque is large when the rotation speed is high, the external pilot pressure is applied to the second pressure receiving surface of the pilot piston by the reduced horsepower of the prime mover. If the horsepower setting of the pump is lowered and the external pilot pressure is released to increase the horsepower setting when the rotation speed increases, the horsepower of the prime mover can be used effectively.
【０００７】[0007]
【実施例】本考案の実施例を図２に基づき説明すると、
同図の符号１は内燃機関や電動機の原動機を示し、これ
に歯車列等の伝動装置２を介して可変容量形の１台の主
ポンプ３と２台の可変容量形の従ポンプ４を接続し、各
ポンプ３、４が同時に該原動機１により駆動されるよう
にした。各ポンプ３、４は油圧が導入されてポンプ容量
を変更する斜板等を作動させるための馬力設定部５を備
えており、各従ポンプ４の馬力設定部５には各従ポンプ
４の吐出回路６、６から分岐してタンク７へ連通する制
御回路８、８の１次絞り９、９と２次絞り１０、１０の
中間部から圧力を導き、その圧力が低いと該馬力設定部
５はポンプ容量を増大させてポンプの設定馬力を増大
し、その圧力が高いと馬力設定部５はポンプ容量を減少
させてポンプの設定馬力を小さくする。該２次絞り１
０、１０は、主ポンプ３の吐出圧の高まりで閉弁作動す
る１つの２次絞り弁１１として構成される。An embodiment of the present invention will be described with reference to FIG.
In the figure, reference numeral 1 denotes a prime mover of an internal combustion engine or an electric motor, to which one variable displacement type main pump 3 and two variable displacement type sub-pumps 4 are connected via a transmission 2 such as a gear train. The pumps 3 and 4 are simultaneously driven by the prime mover 1. Each of the pumps 3 and 4 is provided with a horsepower setting unit 5 for operating a swash plate or the like that changes the pump capacity when hydraulic pressure is introduced, and the horsepower setting unit 5 of each slave pump 4 discharges each slave pump 4. Pressure is derived from an intermediate portion between the primary throttles 9 and 9 and the secondary throttles 10 and 10 of the control circuits 8 and 8 which branch off from the circuits 6 and 6 and communicate with the tank 7, and when the pressure is low, the horsepower setting unit 5 Increases the pump capacity to increase the set horsepower of the pump. If the pressure is high, the horsepower setting unit 5 reduces the pump capacity to decrease the set horsepower of the pump. The secondary aperture 1
Reference numerals 0 and 10 are configured as one secondary throttle valve 11 that operates to close the valve when the discharge pressure of the main pump 3 increases.
【０００８】以上の構成は図１のものと変わりがない
が、本考案の場合、該２次絞り弁１１に主ポンプ３の吐
出圧が作用する第１受圧面１２と導管１３を介して外部
パイロット圧が作用する第２受圧面１４とを有するパイ
ロットピストン１５を設け、該パイロット圧を作用させ
ることにより該パイロットピストン１５が２次絞り弁１
１に制御回路８、８を閉じるように作動を行なわせて従
ポンプ４、４の設定馬力を低く変更できるようにした。
該２次絞り弁１１は、図３に示すように、タンク７へ連
なるタンクポート１６と制御回路８、８に連なる制御ポ
ート１７、１７とを備えた弁筐１８内に、一端のパイロ
ットピストン１５により押されて他端の制御ばね１９に
抗しながら摺動するスプール２０を設け、該スプール２
０の周囲にパイロットピストン１５に押されて摺動する
とき次第に各制御回路８を絞り最終的には閉じるノッチ
形の２次絞り１０、１０を設けた構造とし、該パイロッ
トピストン１５がスプール２０を押す力の加減で２次絞
り１０の面積が変わるようにした。Although the above construction is the same as that of FIG. 1, in the case of the present invention, the secondary throttle valve 11 is externally connected via the first pressure receiving surface 12 on which the discharge pressure of the main pump 3 acts and the conduit 13. A pilot piston 15 having a second pressure receiving surface 14 on which a pilot pressure acts is provided. By applying the pilot pressure, the pilot piston 15
1 was operated so as to close the control circuits 8 and 8, so that the set horsepower of the sub-pumps 4 and 4 could be changed to be lower.
As shown in FIG. 3, the secondary throttle valve 11 has a pilot piston 15 at one end in a valve housing 18 provided with a tank port 16 connected to the tank 7 and control ports 17 connected to the control circuits 8. The spool 20 is slid by being pushed by the control member and sliding against the control spring 19 at the other end.
When the pilot piston 15 is pushed and slid around the control circuit 8, each control circuit 8 is gradually narrowed, and a notch-shaped secondary throttle 10, 10 which is finally closed is provided. The area of the secondary aperture 10 was changed by adjusting the pressing force.
【０００９】パイロットピストン１５に外部パイロット
圧が作用していないときは、図１の場合と同様で、主ポ
ンプ３の吐出圧が高まると２次絞り弁１１が次第に２次
絞り１０を絞るように作動し、従ポンプ４の馬力設定部
５に作用する圧力が高まってそのポンプ容量を減じ、馬
力設定を小さくする。また、主ポンプ３の吐出圧が低け
れば２次絞り弁１１が開くので、従ポンプ４の馬力設定
部５に作用する圧力が低下し、従ポンプ４の馬力設定が
大きくなる。原動機１が回転数の低いときに出力トルク
が小さく、回転数が高いときに出力トルクが大きくなる
特性を持つ場合、原動機１の回転数が低いときに外部パ
イロット圧を作用させて強制的に２次絞り１０を閉じて
おき或いは大きく絞っておき、従ポンプ４の馬力設定を
低下させておくことにより、原動機１を過負荷に陥らせ
ることなくしかも各ポンプ３、４の運転を継続できる。
尚、外部パイロット圧を作用させた状態で従ポンプ４の
馬力設定を行ない、外部パイロット圧を抜くようにすれ
ば、従ポンプ４の馬力設定を低から高へ上げることがで
きる。When the external pilot pressure is not acting on the pilot piston 15, as in the case of FIG. 1, as the discharge pressure of the main pump 3 increases, the secondary throttle valve 11 gradually narrows the secondary throttle 10. When activated, the pressure acting on the horsepower setting section 5 of the secondary pump 4 increases, reducing the pump capacity and reducing the horsepower setting. If the discharge pressure of the main pump 3 is low, the secondary throttle valve 11 is opened, so that the pressure acting on the horsepower setting unit 5 of the slave pump 4 decreases, and the horsepower setting of the slave pump 4 increases. When the motor 1 has a characteristic that the output torque is small when the rotation speed is low and the output torque is large when the rotation speed is high, the external pilot pressure is applied when the rotation speed of the motor 1 is low to force the motor 2. By closing or narrowing the next throttle 10 and lowering the horsepower setting of the slave pump 4, the operation of the pumps 3 and 4 can be continued without overloading the prime mover 1.
If the horsepower of the slave pump 4 is set while the external pilot pressure is applied and the external pilot pressure is released, the horsepower setting of the slave pump 4 can be increased from low to high.
【００１０】[0010]
【考案の効果】以上のように本考案によるときは、１台
の原動機により同時に駆動される複数台の油圧ポンプの
主ポンプ以外の従ポンプの馬力設定を制御する制御回路
の２次絞り弁に外部パイロット圧が作用するパイロット
ピストンを設けたので、該原動機が駆動する複数台のポ
ンプ以外の要因に応じて従ポンプの馬力設定を行なえ、
ポンプ装置全体の馬力を有効利用でき、その構成も簡単
で安価に製作できる等の効果がある。As described above, according to the present invention, the secondary throttle valve of the control circuit for controlling the horsepower setting of the secondary pumps other than the main pump of a plurality of hydraulic pumps driven simultaneously by one prime mover is provided. Since the pilot piston on which the external pilot pressure acts is provided, the horsepower of the slave pump can be set according to factors other than the plurality of pumps driven by the prime mover,
There is an effect that the horsepower of the entire pump device can be effectively used, the configuration thereof is simple, and the pump device can be manufactured at low cost.
【図１】従来例の線図FIG. 1 is a diagram of a conventional example.
【図２】本考案の実施例の線図FIG. 2 is a diagram of an embodiment of the present invention.
【図３】図２の２次絞り弁の具体的断面図FIG. 3 is a specific sectional view of the secondary throttle valve of FIG. 2;
１ 原動機 ３ 主ポンプ ４ 従
ポンプ ５ 馬力設定部 ６ 吐出回路 ７ タ
ンク ８ 制御回路 ９ １次絞り １０ ２
次絞り １１ ２次絞り弁 １２ 第１受圧面 １４
第２受圧面 １５ パイロットピストンReference Signs List 1 motor 3 main pump 4 slave pump 5 horsepower setting section 6 discharge circuit 7 tank 8 control circuit 9 primary throttle 10 2
Secondary throttle 11 Secondary throttle valve 12 First pressure receiving surface 14
2nd pressure receiving surface 15 Pilot piston
Claims (2)
プと少なくとも１台の可変容量形の従ポンプを駆動し、
該従ポンプの吐出回路からタンクへ１次絞りと２次絞り
を有する制御回路を設け、該１次絞りと２次絞りの間の
制御回路を該従ポンプの馬力設定部に接続し、該２次絞
りを該主ポンプの吐出圧の高まりで閉じる２次絞り弁に
構成して該従ポンプの馬力設定を変更するようにした装
置に於いて、該２次絞り弁に該主ポンプの吐出圧が作用
する第１受圧面と、外部パイロット圧が作用する第２受
圧面を有するパイロットピストンを連設して該２次絞り
弁の作動を制御したことを特徴とする可変容量ポンプの
馬力制御装置。1. A single prime mover drives one main pump and at least one variable displacement secondary pump at the same time,
A control circuit having a primary throttle and a secondary throttle is provided from the discharge circuit of the slave pump to the tank; a control circuit between the primary throttle and the secondary throttle is connected to a horsepower setting part of the slave pump; In a device in which the secondary throttle is configured as a secondary throttle valve that closes with an increase in the discharge pressure of the main pump to change the horsepower setting of the secondary pump, the discharge pressure of the main pump is set to the secondary throttle valve. And a pilot piston having a second pressure receiving surface on which an external pilot pressure acts, and a pilot piston having a second pressure receiving surface on which an external pilot pressure acts to control the operation of the secondary throttle valve. .
にタンクへの開口面積を閉じる構成を有することを特徴
とする請求項１に記載の可変容量ポンプの馬力制御装
置。2. The horsepower control device for a variable displacement pump according to claim 1, wherein the secondary throttle valve has a configuration in which an opening area to a tank is gradually closed by movement of a spool.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1992043584U JP2587379Y2 (en) | 1992-06-23 | 1992-06-23 | Horsepower control device for variable displacement pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1992043584U JP2587379Y2 (en) | 1992-06-23 | 1992-06-23 | Horsepower control device for variable displacement pump |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH064388U JPH064388U (en) | 1994-01-21 |
| JP2587379Y2 true JP2587379Y2 (en) | 1998-12-16 |
Family
ID=12667834
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1992043584U Expired - Fee Related JP2587379Y2 (en) | 1992-06-23 | 1992-06-23 | Horsepower control device for variable displacement pump |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2587379Y2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4945962U (en) * | 1972-07-27 | 1974-04-22 | ||
| JPS5618188Y2 (en) * | 1976-11-11 | 1981-04-28 | ||
| JPS5648039Y2 (en) * | 1977-03-25 | 1981-11-10 |
-
1992
- 1992-06-23 JP JP1992043584U patent/JP2587379Y2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH064388U (en) | 1994-01-21 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |