JPH0147645B2 - - Google Patents
Info
- Publication number
- JPH0147645B2 JPH0147645B2 JP56109900A JP10990081A JPH0147645B2 JP H0147645 B2 JPH0147645 B2 JP H0147645B2 JP 56109900 A JP56109900 A JP 56109900A JP 10990081 A JP10990081 A JP 10990081A JP H0147645 B2 JPH0147645 B2 JP H0147645B2
- Authority
- JP
- Japan
- Prior art keywords
- valve
- pressure
- throttle valve
- type pressure
- pressure compensation
- 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
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B23/00—Pumping installations or systems
- F04B23/04—Combinations of two or more pumps
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Fluid-Pressure Circuits (AREA)
- Magnetically Actuated Valves (AREA)
Description
【発明の詳細な説明】
この発明はたとえば車両等に用いれば特に好適
なもので、複数の固定ポンプからの吐出流体を絞
り弁の開度に応じて自動的に合流できるようにし
た自動合流形流量制御回路に関する。Detailed Description of the Invention The present invention is particularly suitable for use in vehicles, etc., and is an automatic merging type in which fluids discharged from a plurality of fixed pumps can be automatically merged according to the opening degree of a throttle valve. It relates to a flow control circuit.
従来、合流形流量制御回路としては、たとえば
第１図に示すように、第１固定ポンプ１′の吐出
流体に第２固定ポンプ２′の吐出流体をチエツク
弁３′を介して合流させて、その合流流体を絞り
弁４′に供給し得るようにし、かつ、上記絞り弁
４′の開度に応じて切換弁５′を操作してアンロー
ド弁６′を介して第２固定ポンプ２′をアンロード
またはオンロードさせて、エネルギー損失を少な
くすると共に、リリーフ弁７′で余剰流体をタン
クに排出しながら減圧形圧力補償弁８′で絞り弁
４′の前後の差圧を一定に制御するようにしたも
のが知られている。 Conventionally, as shown in FIG. 1, for example, as shown in FIG. 1, a merging type flow control circuit combines the fluid discharged from a first fixed pump 1' with the fluid discharged from a second fixed pump 2' via a check valve 3'. The combined fluid can be supplied to the throttle valve 4', and the switching valve 5' is operated according to the opening degree of the throttle valve 4' to supply the fluid to the second fixed pump 2' via the unload valve 6'. is unloaded or on-loaded to reduce energy loss, and while the relief valve 7' discharges excess fluid to the tank, the pressure-reducing pressure compensating valve 8' controls the differential pressure across the throttle valve 4' to a constant level. It is known what made it so.
ところが、この合流形流量制御回路は、上記の
如く、第２固定ポンプ２′を自動的にオンロード
またはアンロードさせることができないという欠
点があり、つまり、電気信号で切換弁５′を操作
してアンロード弁６′をアンロードまたはオンロ
ードさせるために、制御系が複雑、高価になると
いう欠点がある。また、オンロード状態での第
１、第２固定ポンプ１′，２′の負荷圧力は、絞り
弁４′の２次圧力とは無関係に、リリーフ弁７′の
設定圧力となるために、動力損失が大きいという
欠点がある。 However, as mentioned above, this combined flow rate control circuit has the drawback that it is not possible to automatically load or unload the second fixed pump 2'.In other words, the switching valve 5' cannot be operated by an electric signal. Since the unload valve 6' is unloaded or on-loaded by the unload valve 6', the control system is complicated and expensive. In addition, the load pressure of the first and second fixed pumps 1' and 2' in the on-road state becomes the set pressure of the relief valve 7', regardless of the secondary pressure of the throttle valve 4', so that the power The disadvantage is that the loss is large.
この発明の目的は、第２固定ポンプを絞り弁の
開度に応じて自動的にアンロードまたはオンロー
ドさせ得るようにして、制御系を安価、簡単に
し、第２固定ポンプのオンロード状態でのその負
荷圧力を絞り弁の２次側の圧力に応じた圧力とな
るようにして、動力損失を少なくすることにあ
る。 An object of the present invention is to make the control system inexpensive and simple by automatically unloading or on-loading the second fixed pump depending on the opening degree of the throttle valve, and to make the control system inexpensive and simple. The purpose is to reduce power loss by adjusting the load pressure to a pressure corresponding to the pressure on the secondary side of the throttle valve.
この発明は、上記目的を達成するために、第１
固定ポンプのメインラインに可変絞り弁を設け、
この可変絞り弁と固定ポンプとの間のメインライ
ンから分岐したバイパスラインに、第１バイパス
形圧力補償弁を設け、この第１バイパス形圧力補
償弁のパイロツト室とバネ室を上記可変絞り弁前
後のメインラインに連通すると共に、上記第１固
定ポンプと上記可変絞り弁との間のメインライン
にチエツク弁を介して第２固定ポンプを接続し、
上記第２固定ポンプと第１チエツク弁との間から
分岐したバイパスラインに、第２バイパス形圧力
補償弁を介設し、この第２バイパス形圧力補償弁
のパイロツト室を第１チエツク弁の下流側に接続
し、その第２バイパス形圧力補償弁のバネ室を上
記可変絞り弁の下流側に接続する一方、上記第２
バイパス形圧力補償弁のバネ室のバネ圧を上記第
１バイパス形圧力補償弁のバネ室のバネ圧よりも
小さく設定することにより、上記可変絞り弁の開
度が一定以下のときは、第１チエツク弁で逆流の
防止を行ない、第２バイパス形圧力補償弁を開放
させて第２固定ポンプを自動的にアンロードさせ
る一方、上記可変絞り弁の開度が一定以上のとき
には、自動的に、第２バイパス形圧力補償弁を動
作させ、そのバネ圧に応じた圧力に可変絞り弁の
前後の差圧を制御し得るようにして、第１チエツ
ク弁を開放して第１、第２固定ポンプの吐出流体
を合流させると共に、第１、第２固定ポンプの合
流負荷圧力を可変絞り弁の２次圧力に応じた圧力
に制御して省エネルギを図つたことを特徴として
いる。 In order to achieve the above object, this invention has the following features:
A variable throttle valve is installed in the main line of the fixed pump,
A first bypass type pressure compensation valve is provided in a bypass line branched from the main line between the variable throttle valve and the fixed pump, and the pilot chamber and spring chamber of the first bypass type pressure compensation valve are connected to the front and back of the variable throttle valve. a second fixed pump connected to the main line between the first fixed pump and the variable throttle valve via a check valve;
A second bypass type pressure compensation valve is interposed in the bypass line branched from between the second fixed pump and the first check valve, and the pilot chamber of the second bypass type pressure compensation valve is connected downstream of the first check valve. the spring chamber of the second bypass type pressure compensation valve is connected to the downstream side of the variable throttle valve;
By setting the spring pressure of the spring chamber of the bypass type pressure compensation valve to be smaller than the spring pressure of the spring chamber of the first bypass type pressure compensation valve, when the opening degree of the variable throttle valve is below a certain level, the first The check valve prevents backflow, the second bypass type pressure compensation valve is opened, and the second fixed pump is automatically unloaded, while when the opening degree of the variable throttle valve is above a certain level, automatically: The second bypass type pressure compensation valve is operated to control the differential pressure before and after the variable throttle valve to a pressure corresponding to the spring pressure, and the first check valve is opened to control the first and second fixed pumps. This is characterized in that the discharge fluids of the pumps are combined, and the combined load pressure of the first and second fixed pumps is controlled to a pressure that corresponds to the secondary pressure of the variable throttle valve, thereby saving energy.
以下、この発明を図示の実施例について詳細に
説明する。 Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.
第２図において、１は第１固定ポンプ、２と３
は第１固定ポンプ１に接続したメインライン４に
上流側より順次設けた減圧形圧力補償弁と可変絞
り弁、５は第１固定ポンプ１と減圧形圧力補償弁
２との間のメインライン４から分岐したバイパス
ライン６に設けた圧力制御弁の一例としての第１
バイパス形圧力補償弁、７は第２固定ポンプ、８
は第２固定ポンプ７と減圧形圧力補償弁２よりも
上流側のメインライン４とを接続するライン１１
に設けた第１チエツク弁、１２は第２固定ポンプ
７と第１チエツク弁８との間から分岐したバイパ
スライン９に設けた第２バイパス形圧力補償弁、
１３は第３固定ポンプ、１４は第３固定ポンプ１
３と減圧形圧力補償弁２よりも上流側のメインラ
イン４とを接続するライン１５に設けた第２チエ
ツク弁、１６は第３固定ポンプ１３と第２チエツ
ク弁１４との間から分岐したバイパスライン１７
に設けた第３バイパス形圧力補償弁であつて、上
記第１、第２、第３バイパス形圧力補償弁５，１
２，１６の各バネ室２５，２６，２７は夫々上記
絞り弁３の下流側に接続して、第１バイパス形圧
力補償弁５は減圧形圧力補償の上流側と絞り弁３
の下流側との差圧をバネ室２５のバネ３１のバネ
圧△P1に、また第２バイパスパス形圧力補償弁
１２は上記差圧をバネ室２６のバネ３２のバネ圧
△P2に、また第３バイパス形圧力補償弁１６は
上記差圧をバネ室２７のバネ３３のバネ圧△P3
に制御し得るようにしている。 In Fig. 2, 1 is the first fixed pump, 2 and 3
5 is a pressure reducing type pressure compensating valve and a variable throttle valve provided sequentially from the upstream side on the main line 4 connected to the first fixed pump 1, and 5 is a main line 4 between the first fixed pump 1 and the pressure reducing type pressure compensating valve 2. A first pressure control valve as an example of a pressure control valve provided in a bypass line 6 branched from
Bypass type pressure compensation valve, 7 is a second fixed pump, 8
is a line 11 connecting the second fixed pump 7 and the main line 4 upstream of the pressure reducing valve 2;
12 is a second bypass type pressure compensation valve provided in a bypass line 9 branched from between the second fixed pump 7 and the first check valve 8;
13 is the third fixed pump, 14 is the third fixed pump 1
3 and the main line 4 on the upstream side of the pressure reducing type pressure compensation valve 2. 16 is a bypass branched from between the third fixed pump 13 and the second check valve 14. line 17
a third bypass type pressure compensation valve provided in the first, second and third bypass type pressure compensation valves 5, 1;
The spring chambers 25, 26, and 27 are respectively connected to the downstream side of the throttle valve 3, and the first bypass type pressure compensation valve 5 is connected to the upstream side of the pressure reduction type pressure compensation and the throttle valve 3.
The differential pressure between the downstream side of , and the third bypass type pressure compensation valve 16 converts the above differential pressure into a spring pressure △P 3 of the spring 33 of the spring chamber 27.
I'm trying to get it under control.
上記各バネ圧△P1、△P2、△P3の関係は（△
P1＞△P2＞△P3）に設定する。たとえば、△P1
＝10Kg／cm2、△P2＝８Kg／cm2、△P3＝６Kg／cm2
に設定する。上記減圧形圧力補償弁２のバネ室３
５のバネ３６のバネ圧△P0は、上記第３バイパ
ス形圧力補償弁１６のバネ圧△P3よりも小さく
設定する。たとえば、△P0＝３Kg／cm2とする。 The relationship between the above spring pressures △P 1 , △P 2 , △P 3 is (△
P 1 > △P 2 > △P 3 ). For example, △P 1
= 10Kg/cm 2 , △P 2 = 8Kg/cm 2 , △P 3 = 6Kg/cm 2
Set to . Spring chamber 3 of the above pressure reducing type pressure compensation valve 2
The spring pressure ΔP 0 of the spring 36 of No. 5 is set smaller than the spring pressure ΔP 3 of the third bypass type pressure compensation valve 16. For example, ΔP 0 =3Kg/cm 2 .
また、上記第２バイパス形圧力補償弁１２のパ
イロツト室２１はパイロツトライン２２を介して
第１チエツク弁８よりも下流側のライン１１に接
続すると共に、第３バイパス形圧力補償弁１６の
パイロツト室２３はパイロツトライン２４を介し
て第２チエツク弁１４よりも下流側のライン１５
に接続する。 The pilot chamber 21 of the second bypass type pressure compensation valve 12 is connected to the line 11 downstream of the first check valve 8 via a pilot line 22, and the pilot chamber 21 of the third bypass type pressure compensation valve 16 is connected to the line 11 downstream of the first check valve 8 via a pilot line 22. 23 is a line 15 downstream of the second check valve 14 via the pilot line 24.
Connect to.
上記構成の自動合流形流量制御回路は次のよう
に動作する。 The automatic merging type flow control circuit configured as described above operates as follows.
いま、絞り弁３の開度を第３図中の開度X2以
下の一定値に設定するとする。 Now, assume that the opening degree of the throttle valve 3 is set to a constant value less than or equal to the opening degree X2 in FIG.
この瞬間、第１バイパス形圧力補償５は余剰流
体をバイパスライン６から排出して減圧形圧力補
償弁２の上流側と絞り弁３の下流側との差圧をバ
ネ圧△P1に制御しようとし、第２バイパス形圧
力補償弁１２は余剰流体を第２固定ポンプ７と第
１チエツク弁８との間からバイパスライン９を通
してタンクに排出して上記差圧をバネ圧△P2に
制御しようとし、第３バイパス形圧力補償弁１３
は余剰流体を第３固定ポンプ１３と第２チエツク
弁１４との間からバイパスライン１７を通してタ
ンクに排出して上記差圧をバネ圧△P3に制御し
ようとする。ところで、絞り弁３の開度が小さ
く、かつ、△P1＞△P2＞△P3であるために、絞
り弁３に対する所要流量は第１固定ポンプ１の吐
出流量のみで十分であり、したがつて、第１バイ
パス形圧力補償弁５は上記差圧△P1に制御し、
また第１、第２チエツク弁８，１４は夫々その前
後の差圧のために閉鎖する。なお、減圧形圧力補
償弁２はそのバネ圧△P0に絞り弁３の前後の差
圧を制御する。 At this moment, the first bypass type pressure compensation 5 discharges the excess fluid from the bypass line 6 and controls the differential pressure between the upstream side of the pressure reduction type pressure compensation valve 2 and the downstream side of the throttle valve 3 to the spring pressure △P 1 . Then, the second bypass type pressure compensation valve 12 discharges surplus fluid from between the second fixed pump 7 and the first check valve 8 to the tank through the bypass line 9 to control the differential pressure to the spring pressure △P 2 . and the third bypass type pressure compensation valve 13
attempts to control the differential pressure to the spring pressure ΔP 3 by discharging excess fluid from between the third fixed pump 13 and the second check valve 14 to the tank through the bypass line 17. By the way, since the opening degree of the throttle valve 3 is small and △P 1 > △P 2 > △P 3 , the required flow rate for the throttle valve 3 is only the discharge flow rate of the first fixed pump 1, Therefore, the first bypass type pressure compensation valve 5 controls the differential pressure to the above-mentioned differential pressure △P 1 ,
Further, the first and second check valves 8 and 14 are respectively closed due to the differential pressure across them. Note that the pressure reducing type pressure compensation valve 2 controls the differential pressure across the throttle valve 3 to its spring pressure ΔP 0 .
一方、このとき、第２バイパス形圧力補償弁１
２のパイロツト室２１とバネ２６とには、夫々、
減圧形圧力補償弁２の上流側の圧力と絞り弁３の
下流側の圧力とが伝えられている。このため、上
記パイロツト室２１とバネ室２６との差圧は、バ
ネ圧△P2よりも大きな△P1となつて、第２バイ
パス形圧力補償弁１２は完全に開放して静止す
る。したがつて、第２固定ポンプ７はアンロード
状態となつている。また、同様に、第３バイパス
形圧力補償弁１６のパイロツト室２３とバネ室２
７にも、夫々、減圧形圧力補償弁２の上流側の圧
力と絞り弁３の下流側の圧力とが伝えられて、上
記パイロツト室２３とバネ室２７との差圧は、そ
のバネ圧△P3よりも大きな△P1となる。このた
め、第３バイパス形圧力補償弁１６は完全に開放
して静止し、第３固定ポンプ１３はアンロード状
態となる。 On the other hand, at this time, the second bypass type pressure compensation valve 1
The pilot chamber 21 and spring 26 of No. 2 each have a
The pressure on the upstream side of the pressure reducing type pressure compensation valve 2 and the pressure on the downstream side of the throttle valve 3 are transmitted. Therefore, the pressure difference between the pilot chamber 21 and the spring chamber 26 becomes ΔP 1 which is greater than the spring pressure ΔP 2 , and the second bypass type pressure compensating valve 12 is completely opened and stands still. Therefore, the second fixed pump 7 is in an unloaded state. Similarly, the pilot chamber 23 and the spring chamber 2 of the third bypass type pressure compensation valve 16
The pressure on the upstream side of the pressure reducing type pressure compensation valve 2 and the pressure on the downstream side of the throttle valve 3 are also transmitted to the valves 7 and 7, respectively, and the differential pressure between the pilot chamber 23 and the spring chamber 27 is equal to the spring pressure △. △P 1 is larger than P 3 . Therefore, the third bypass type pressure compensation valve 16 is completely opened and stands still, and the third fixed pump 13 is in an unloaded state.
したがつて、上記絞り弁３の開度が第３図中の
X2以下の場合には、第２、第３固定ポンプ７，
１３をアンロードさせる上に、第１固定ポンプ１
の負荷圧力を絞り弁３の２次側圧力に応じて、そ
れよりもバネ圧△P1だけ高い圧力に制御してい
るから、この自動合流形流量制御回路は絞り弁の
２次側圧力とは無関係に固定ポンプの負荷圧力が
リリーフ弁の設定圧力となる合流形流量制御回路
に比べて、動力損失が少なくなつている。 Therefore, the opening degree of the throttle valve 3 is as shown in FIG.
If X 2 or less, the second and third fixed pumps 7,
13 and the first stationary pump 1
Since the load pressure is controlled to a pressure higher than the secondary pressure of the throttle valve 3 by the spring pressure △P 1 , this automatic merging type flow control circuit has a pressure equal to the secondary pressure of the throttle valve 3. Compared to a combined flow control circuit in which the load pressure of the fixed pump becomes the set pressure of the relief valve, the power loss is reduced.
次に、絞り弁３の開度を第３図中X2よりも大
きくする。そうすると、第１固定ポンプ１からの
みの吐出流体では、減圧形圧力補償弁２の上流側
と絞り弁３の下流側との差圧を、バイパス形圧力
補償弁５が完全に閉鎖しても、△P1に制御する
ことができなくなる。そして、絞り弁３の開度を
さらに大きくすると、それについて、上記差圧は
低下し、絞り弁３の開度が第３図中のS2になる
と、上記差圧は△P2となる。一般的に開度X2≒
S2か、あるいは、わずかにS2の方が大であるとさ
れている。 Next, the opening degree of the throttle valve 3 is made larger than X2 in FIG. Then, with the fluid discharged only from the first fixed pump 1, even if the bypass type pressure compensation valve 5 completely closes the differential pressure between the upstream side of the pressure reducing type pressure compensation valve 2 and the downstream side of the throttle valve 3, It becomes impossible to control △P 1 . When the opening degree of the throttle valve 3 is further increased, the differential pressure decreases, and when the opening degree of the throttle valve 3 reaches S2 in FIG. 3, the differential pressure becomes ΔP2 . Generally, opening degree X 2 ≒
S 2 , or S 2 is said to be slightly larger.
この開度がX2からS2になるまでの過渡領域が
すぎて、わずかにS2より大きくなつたとする。 Suppose that the transient region from when the opening degree changes from X 2 to S 2 has passed and it has become slightly larger than S 2 .
そうすると、第１固定ポンプ１からの吐出流量
のみでは不足して、減圧形圧力補償弁２の上流側
と絞り弁３の下流側との差圧が△P2よりも小さ
くなろうとするが、このとき、第２バイパス形圧
力補償弁１２が上記差圧をバネ圧△P2にするよ
うに開閉動作するから、第２固定ポンプ７は自動
的にオンロードされ、その吐出流体は第１チエツ
ク弁８を通つて第１固定ポンプ１からの流体に合
流する。この合流した流体は減圧形圧力補償弁２
を通つて、絞り弁３に供給される。上記減圧形圧
力補償弁２は絞り弁３の前後の差圧をバネ圧△
P0に制御する。 Then, the discharge flow rate from the first fixed pump 1 alone will be insufficient, and the differential pressure between the upstream side of the pressure reducing type pressure compensation valve 2 and the downstream side of the throttle valve 3 will become smaller than △P 2 . At this time, the second bypass type pressure compensation valve 12 opens and closes so that the differential pressure becomes the spring pressure △ P2 , so the second fixed pump 7 is automatically on-loaded and the discharged fluid flows through the first check valve. 8 to join the fluid from the first stationary pump 1 . This combined fluid is transferred to the pressure reducing type pressure compensating valve 2.
It is supplied to the throttle valve 3 through. The above-mentioned pressure reducing type pressure compensation valve 2 adjusts the differential pressure before and after the throttle valve 3 to a spring pressure △
Control to P 0 .
したがつて、上記開度がS2以上の状態では、第
１、第２固定ポンプ１，７をオンロードさせて、
第２バイパス形圧力補償弁１２によつて減圧形圧
力補償弁２の上流側と絞り弁３の下流側との差圧
をバネ圧△P2に制御している。したがつて、第
１、第２固定ポンプ１，７の負荷圧力は（２次圧
力＋△P2）となるから、この合流形流量制御回
路は従来の合流形回路に比べて省エネルギ的であ
る。また、このとき、第１バイパス形圧力補償弁
３は、そのバネ圧△P1が上記差圧△P2より大き
いため、閉鎖している。また、第３バイパス形圧
力補償弁１６は、そのバネ圧△P3が上記差圧△
P2よりも小さいために、開放して静止している。
このため、第３固定ポンプ１３はアンロード状態
にある。 Therefore, when the opening degree is S2 or more, the first and second fixed pumps 1 and 7 are on-loaded,
The second bypass type pressure compensation valve 12 controls the differential pressure between the upstream side of the pressure reduction type pressure compensation valve 2 and the downstream side of the throttle valve 3 to a spring pressure ΔP 2 . Therefore, the load pressure of the first and second fixed pumps 1 and 7 is (secondary pressure + △P 2 ), so this combined flow rate control circuit is more energy-saving than the conventional combined type circuit. be. Moreover, at this time, the first bypass type pressure compensation valve 3 is closed because its spring pressure ΔP 1 is greater than the differential pressure ΔP 2 . Further, the third bypass type pressure compensation valve 16 has a spring pressure △P 3 of the above-mentioned differential pressure △
Since it is smaller than P 2 , it is open and at rest.
Therefore, the third fixed pump 13 is in an unloaded state.
次に、絞り弁３の開度をさらに大きくして第３
図中のX3よりも大きくする。 Next, the opening degree of the throttle valve 3 is further increased and the third
Make it larger than X 3 in the diagram.
そうすると、第１、第２固定ポンプ１，７から
の流体のみでは絞り弁３に対して流量が不足する
ため、減圧形圧力補償弁２の上流側と絞り弁３の
下流側との差圧は△P2よりも低くなる。そして、
絞り弁３の開度をさらに大きくすると、それにつ
れて、上記差圧は低下し、絞り弁３の開度が第３
図中のS3となると、上記差圧は△P3となる。 In this case, the flow rate of the fluid from the first and second fixed pumps 1 and 7 alone is insufficient for the throttle valve 3, so the differential pressure between the upstream side of the pressure reducing type pressure compensation valve 2 and the downstream side of the throttle valve 3 is △P will be lower than 2 . and,
When the opening degree of the throttle valve 3 is further increased, the above-mentioned differential pressure decreases, and the opening degree of the throttle valve 3 reaches the third level.
At S 3 in the figure, the above differential pressure becomes ΔP 3 .
この開度がX3からS3まで過渡領域においても、
第１、第２固定ポンプ１，７はオンロード状態に
あり、第３固定ポンプ１３はアンロード状態にあ
る。 Even in the transient region where this opening degree is from X 3 to S 3 ,
The first and second fixed pumps 1 and 7 are in an on-load state, and the third fixed pump 13 is in an unload state.
次に、絞り弁３の開度を第３図中S3よりも大き
くする。 Next, the opening degree of the throttle valve 3 is made larger than S3 in FIG.
そうすると、減圧形圧力補償弁２の上流側と絞
り弁３の下流側との差圧が△P3よりも大きくな
ろうとするが、第３バイパス形圧力補償弁１６が
上記差圧をバネ圧△P3にするように開閉動作す
るから、第３固定ポンプ１３は自動的にオンロー
ドされ、その吐出流体は第２チエツク弁１４を通
つて第１、第２固体ポンプ１，７からの吐出流体
に合流する。そして、このとき、第１、第２、第
３固定ポンプ１，７，１３は全てオンロード状態
になつており、第３バイパス形圧力補償弁１６は
減圧形圧力補償弁２の上流側と絞り弁３の下流側
との差圧を△P3に制御しており、減圧形圧力補
償弁２は絞り弁３の前後の差圧を△P0に制御し
ている。また、第２、第３バイパス形圧力補償弁
５，１２は共に閉鎖している。 Then, the differential pressure between the upstream side of the pressure reducing type pressure compensation valve 2 and the downstream side of the throttle valve 3 tends to become larger than △P 3 , but the third bypass type pressure compensation valve 16 reduces the pressure difference by using the spring pressure △ P3 , the third fixed pump 13 is automatically on-loaded, and its discharge fluid passes through the second check valve 14 to the discharge fluid from the first and second solid pumps 1 and 7. to join. At this time, the first, second, and third fixed pumps 1, 7, and 13 are all in the on-load state, and the third bypass type pressure compensation valve 16 is connected to the upstream side of the pressure reduction type pressure compensation valve 2 and the throttle. The differential pressure between the valve 3 and the downstream side is controlled to ΔP 3 , and the pressure reducing type pressure compensation valve 2 controls the differential pressure across the throttle valve 3 to ΔP 0 . Further, both the second and third bypass type pressure compensation valves 5 and 12 are closed.
このように、この自動合流形流量制御回路は、
絞り弁３の開度の増大に応じて、第１、第２、第
３固定ポンプ１，７，１３を順次自動的にオンロ
ードさせるのである。また、逆に、絞り弁３の開
度を減少させると、容易に分かるように、第３、
第２、第１固定ポンプ１３，７，１を順次自動的
にアンロードさせる。第３図中の領域A1は第１
固定ポンプ１をオンロードさせ、領域A2は第１、
第２固定ポンプ１，７をオンロードさせ、領域
A3は第１、第２、第３固定ポンプ１，７，１３
をオンロードさせる。 In this way, this automatic merging type flow control circuit
In response to an increase in the opening degree of the throttle valve 3, the first, second, and third fixed pumps 1, 7, and 13 are automatically turned on-load in sequence. Conversely, if the opening degree of the throttle valve 3 is decreased, as can be easily seen, the third
The second and first fixed pumps 13, 7, and 1 are automatically unloaded in sequence. Area A 1 in Figure 3 is the first
Fixed pump 1 is on-loaded, area A 2 is the first,
The second fixed pumps 1 and 7 are on-loaded, and the area
A 3 is the first, second, and third fixed pumps 1, 7, 13
onload.
上記実施例においては、減圧形圧力補償弁２で
絞り弁３の前後の差圧を常に一定に制御するよう
にしたから、第３図中曲線Ｑに示す如く、絞り弁
３の出力流量は絞り弁３の開度に略比例した曲線
となる。但し、減圧形圧力補償弁２を除去する
と、第３図中の曲線Ｂに示す如く、上記過渡領域
は明確に現われ、絞り弁３の出力流量の増大しな
い区間が生ずる。 In the above embodiment, since the pressure reducing type pressure compensating valve 2 is used to always control the differential pressure across the throttle valve 3 to a constant value, the output flow rate of the throttle valve 3 is reduced as shown by curve Q in FIG. The curve is approximately proportional to the opening degree of the valve 3. However, when the pressure reducing type pressure compensating valve 2 is removed, the above-mentioned transient region clearly appears as shown by curve B in FIG. 3, and a section where the output flow rate of the throttle valve 3 does not increase occurs.
上記実施例では、第３固定ポンプ７、第３バイ
パス形圧力補償弁１６および第２チエツク弁１４
からなる系を付加したが、これは省略してもよ
く、さらに、固定ポンプ、バイパス形圧力補償
弁、チエツク弁からなる系は３個以上の複数個設
けてもよい。なお、この発明で、可変絞り弁とは
負荷圧検知ポート付絞り切換弁をも含む概念であ
る。 In the above embodiment, the third fixed pump 7, the third bypass type pressure compensation valve 16 and the second check valve 14
Although a system consisting of a fixed pump, a bypass type pressure compensation valve, and a check valve is added, this may be omitted, and three or more systems consisting of a fixed pump, a bypass type pressure compensation valve, and a check valve may be provided. In this invention, the variable throttle valve is a concept that also includes a throttle switching valve with a load pressure detection port.
以上の説明で明らかな如く、この発明によれ
ば、第１固定ポンプのメインラインに可変絞り弁
を設け、この可変絞り弁と固定ポンプとの間のメ
インラインから分岐したバイパスラインに、第１
バイパス形圧力補償弁を設け、この第１バイパス
形圧力補償弁のパイロツト室とバネ室を上記可変
絞り弁前後のメインラインに連通すると共に、上
記第１固定ポンプと上記可変絞り弁との間のメイ
ンラインにチエツク弁を介して第２固定ポンプを
接続し、上記第２固定ポンプと第１チエツク弁と
の間から分岐したバイパスラインに、第２バイパ
ス形圧力補償弁を介設し、この第２バイパス形圧
力補償弁のパイロツト室を第１チエツク弁の下流
側に接続し、その第２バイパス形圧力補償弁のバ
ネ室を上記可変絞り弁の下流側に接続する一方、
上記第２バイパス形圧力補償弁のバネ室のバネ圧
を上記第１バイパス形圧力補償弁のバネ室のバネ
圧よりも小さく設定したから、可変絞り弁の開度
に応動して、第１、第２固定ポンプを自動的にア
ンロード、オンロードさせることができ、したが
つて、制御系を簡単、安価にでき、しかも、第
１、第２固定ポンプのオンロード状態でその合流
負荷圧力はバイパス形圧力補償弁の作動により、
絞り弁の２次側圧力に応じた圧力となり、動力損
失を少なくすることができる。 As is clear from the above description, according to the present invention, a variable throttle valve is provided in the main line of the first fixed pump, and a bypass line branched from the main line between the variable throttle valve and the fixed pump is connected to the first fixed pump.
A bypass type pressure compensation valve is provided, and a pilot chamber and a spring chamber of the first bypass type pressure compensation valve are communicated with the main line before and after the variable throttle valve, and a line between the first fixed pump and the variable throttle valve is communicated with the main line before and after the variable throttle valve. A second fixed pump is connected to the main line via a check valve, and a second bypass type pressure compensation valve is interposed in a bypass line branched from between the second fixed pump and the first check valve. A pilot chamber of a two-bypass type pressure compensation valve is connected to the downstream side of the first check valve, and a spring chamber of the second bypass type pressure compensation valve is connected to the downstream side of the variable throttle valve,
Since the spring pressure of the spring chamber of the second bypass type pressure compensation valve is set to be smaller than the spring pressure of the spring chamber of the first bypass type pressure compensation valve, the first The second fixed pump can be automatically unloaded and on-loaded, so the control system can be made simple and inexpensive. Moreover, when the first and second fixed pumps are on-loaded, their combined load pressure is By the operation of the bypass type pressure compensation valve,
The pressure corresponds to the secondary side pressure of the throttle valve, and power loss can be reduced.
第１図は従来の合流形流量制御回路の回路図、
第２図は本発明の一実施例に係る自動合流形流量
制御回路の回路図、第３図は第２図に示す絞り弁
の開度と出力流量との関係を示すグラフである。
１……第１固定ポンプ、３……可変絞り弁、５
……第１バイパス形圧力補償弁、７……第２固定
ポンプ、８……第１チエツク弁、１２……第２バ
イパス形圧力補償弁。
Figure 1 is a circuit diagram of a conventional combined flow rate control circuit.
FIG. 2 is a circuit diagram of an automatic merging type flow rate control circuit according to an embodiment of the present invention, and FIG. 3 is a graph showing the relationship between the opening degree of the throttle valve shown in FIG. 2 and the output flow rate. 1...First fixed pump, 3...Variable throttle valve, 5
...First bypass type pressure compensation valve, 7...Second fixed pump, 8...First check valve, 12...Second bypass type pressure compensation valve.
Claims (1)
り弁３を設け、この可変絞り弁３と固定ポンプ１
との間のメインライン４から分岐したバイパスラ
イン６に、第１バイパス形圧力補償弁５を設け、
この第１バイパス形圧力補償弁５のパイロツト室
とバネ室を上記可変絞り弁３前後のメインライン
４に連通すると共に、上記第１固定ポンプ１と上
記可変絞り弁３との間のメインライン４にチエツ
ク弁８を介して第２固定ポンプ７を接続し、上記
第２固定ポンプ７と第１チエツク弁８との間から
分岐したバイパスライン９に、第２バイパス形圧
力補償弁１２を介設し、この第２バイパス形圧力
補償弁１２のパイロツト室２１を第１チエツク弁
８の下流側に接続し、その第２バイパス形圧力補
償弁１２のバネ室２６を上記可変絞り弁３の下流
側に接続する一方、上記第２バイパス形圧力補償
弁１２のバネ室のバネ圧（△P2）を上記第１バ
イパス形圧力補償弁５のバネ室のバネ圧（△P1）
よりも小さく設定したことを特徴とする自動合流
形流量制御回路。1 A variable throttle valve 3 is provided in the main line 4 of the first fixed pump 1, and the variable throttle valve 3 and the fixed pump 1
A first bypass type pressure compensation valve 5 is provided on a bypass line 6 branched from the main line 4 between the
The pilot chamber and spring chamber of the first bypass type pressure compensation valve 5 are communicated with the main line 4 before and after the variable throttle valve 3, and the main line 4 between the first fixed pump 1 and the variable throttle valve 3 is connected to the main line 4 between the first fixed pump 1 and the variable throttle valve 3. A second fixed pump 7 is connected to the pump via a check valve 8, and a second bypass type pressure compensation valve 12 is interposed in a bypass line 9 branched from between the second fixed pump 7 and the first check valve 8. The pilot chamber 21 of the second bypass type pressure compensation valve 12 is connected to the downstream side of the first check valve 8, and the spring chamber 26 of the second bypass type pressure compensation valve 12 is connected to the downstream side of the variable throttle valve 3. On the other hand, the spring pressure (△P2) in the spring chamber of the second bypass type pressure compensation valve 12 is connected to the spring pressure (△P1) in the spring chamber of the first bypass type pressure compensation valve 5.
An automatic merging type flow control circuit characterized in that the flow rate is set smaller than .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10990081A JPS5813278A (en) | 1981-07-13 | 1981-07-13 | Flow control circuit capable of joining fluid flows automatically |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10990081A JPS5813278A (en) | 1981-07-13 | 1981-07-13 | Flow control circuit capable of joining fluid flows automatically |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5813278A JPS5813278A (en) | 1983-01-25 |
| JPH0147645B2 true JPH0147645B2 (en) | 1989-10-16 |
Family
ID=14521999
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10990081A Granted JPS5813278A (en) | 1981-07-13 | 1981-07-13 | Flow control circuit capable of joining fluid flows automatically |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5813278A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004316832A (en) * | 2003-04-18 | 2004-11-11 | Nissan Motor Co Ltd | Hydraulic control device for continuously variable transmission |
| GB2478120B (en) * | 2010-02-24 | 2013-03-13 | Torotrak Dev Ltd | Fluid supply for continuously variable transmission |
| WO2020136841A1 (en) * | 2018-12-27 | 2020-07-02 | 株式会社島津製作所 | Load-sensitive hydraulic fluid supply device for industrial vehicle, and industrial vehicle |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5824007Y2 (en) * | 1978-03-15 | 1983-05-23 | ダイキン工業株式会社 | hydraulic circuit |
| JPS5670106A (en) * | 1979-11-12 | 1981-06-11 | Daikin Ind Ltd | Combination fluid circuit |
-
1981
- 1981-07-13 JP JP10990081A patent/JPS5813278A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5813278A (en) | 1983-01-25 |
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