JPS60176737A - Power match type accumulator circuit - Google Patents
Power match type accumulator circuitInfo
- Publication number
- JPS60176737A JPS60176737A JP3294284A JP3294284A JPS60176737A JP S60176737 A JPS60176737 A JP S60176737A JP 3294284 A JP3294284 A JP 3294284A JP 3294284 A JP3294284 A JP 3294284A JP S60176737 A JPS60176737 A JP S60176737A
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- valve
- flow rate
- accumulator
- control 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.)
- Pending
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
- B29C45/17—Component parts, details or accessories; Auxiliary operations
- B29C45/76—Measuring, controlling or regulating
- B29C45/82—Hydraulic or pneumatic circuits
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
- B29C45/17—Component parts, details or accessories; Auxiliary operations
- B29C45/76—Measuring, controlling or regulating
- B29C45/82—Hydraulic or pneumatic circuits
- B29C2045/824—Accumulators
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
- B29C45/17—Component parts, details or accessories; Auxiliary operations
- B29C45/76—Measuring, controlling or regulating
- B29C45/82—Hydraulic or pneumatic circuits
- B29C2045/826—Plurality of hydraulic actuators driven by one hydraulic pump
Abstract
Description
【発明の詳細な説明】
本発明は射出成形機におけるバワーマ・ノチ式アキエム
レータ回路に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a Bowerma-Nochi type Achiemulator circuit for an injection molding machine.
従来パワーマツチ式油圧回路は、射出成形機の型開閉、
射出、可塑化全てに利用され、省エネルギーの効果を発
揮している。即ち、パワーマツチ式油圧回路は、可変吐
出ポンプと流量調整弁により構成されており、アクチュ
エータの作動に必要な流量、圧力をポンプが吐出する理
想的なものであり、従来のシステムの中で最も省エネ効
果が大きい回路である。Conventional Power Match hydraulic circuits are used to open and close injection molding machines.
It is used for both injection and plasticization, and is effective in saving energy. In other words, the Power Match type hydraulic circuit is composed of a variable discharge pump and a flow rate adjustment valve, and is ideal for the pump to discharge the flow rate and pressure necessary for operating the actuator, and is the most energy-saving among conventional systems. This is a highly effective circuit.
第１図は従来の射出成形機におけるパワーマツチ式油圧
回路の１例を示し、１は型開閉シリンダ、２は射出シリ
ンダ、３はスクリュ、４はスクリュ３を回転させるため
の油圧モータ、５は比例制御弁６を介し、電磁切換弁７
．８．９を経て、夫々油圧モータ４、射出シリンダ２及
び型開閉シリンダ１に圧油を供給する可変油圧ポンプで
ある。また１０はバルブ、１１はパイロットポートであ
る。Figure 1 shows an example of a power match type hydraulic circuit in a conventional injection molding machine, where 1 is a mold opening/closing cylinder, 2 is an injection cylinder, 3 is a screw, 4 is a hydraulic motor for rotating the screw 3, and 5 is a proportional Through the control valve 6, the electromagnetic switching valve 7
．． 8.9 is a variable hydraulic pump that supplies pressure oil to the hydraulic motor 4, injection cylinder 2, and mold opening/closing cylinder 1, respectively. Further, 10 is a valve, and 11 is a pilot port.
さて第１図の射出成形機におけるパワーマツチ式油圧回
路において、型開酢シリンダ１、射出シリンダ２及び油
圧モータ４の動作は、可変油圧ポンプ５からの圧油が、
パイロットポート１１を有する比例制御弁６を通って流
量制御され、夫々電磁切換弁９．８．７を介して各動作
が制御される。Now, in the power match type hydraulic circuit in the injection molding machine shown in FIG.
The flow rate is controlled through a proportional control valve 6 with a pilot port 11, and each operation is controlled via a respective electromagnetic switching valve 9.8.7.
ここで比例制御弁６が動作しない時は、パイロットボー
ト１１が図示の如くタンク１２に繋がり、バルブ１０が
右方向に押され、可変油圧ポンプ５の吐出量は、はぼ零
となる。When the proportional control valve 6 does not operate, the pilot boat 11 is connected to the tank 12 as shown, the valve 10 is pushed to the right, and the discharge amount of the variable hydraulic pump 5 becomes almost zero.
次に比例制御弁６が動作すると、パイロットボート１１
は負荷ラインに繋がり、負荷に応じた圧力と流量で制御
される。Next, when the proportional control valve 6 operates, the pilot boat 11
is connected to the load line and controlled by the pressure and flow rate according to the load.
しかしながら第１図の油圧回路においては、各動作、特
に型開閉シリンダ１、射出シリンダ２の流量の変化が激
しい為、ポンプの吐出量制御部の耐久性に劣る欠点があ
り、また回路構成として、流量減少ζ゛時にはサージ圧
が発生し、かつその頻度が高くなる為、ポンプその他の
機器の耐久性が悪い等の欠点があった。また一般に射出
成形機では、型開閉、射出は、迅速な応答速度を要求さ
れるが、第１図の油圧回路によるとこれらの応答速度が
遅い欠点があった。However, in the hydraulic circuit shown in Fig. 1, each operation, especially the flow rate of the mold opening/closing cylinder 1 and the injection cylinder 2, changes drastically, so there is a drawback that the durability of the pump discharge amount control section is poor, and the circuit configuration is When the flow rate decreases, surge pressure occurs and increases in frequency, resulting in disadvantages such as poor durability of pumps and other equipment. Furthermore, in general, injection molding machines require quick response speeds for mold opening/closing and injection, but the hydraulic circuit shown in FIG. 1 has the disadvantage that these response speeds are slow.
本発明は前記従来の欠点を解消するために提案されたも
ので、アキュムレータと流量調整弁を組合せて型開閉動
作及び射出動作の制御を行なう夫々の制御回路と、可変
油圧ポンプからの圧油を前記アキュムレータに蓄圧する
回路と、同回路から分岐したスクリュ回転用の油圧モー
タに至る回路上に設けられた流量制御弁とを備え、同流
量制御弁はパイロットボートを有し、同ボートは前記流
量制御弁が動作していない時は前記油圧モータに前記油
圧ポンプから圧油を送る回路を遮断する位置にあり、同
流量制御弁が動作すると前記油圧モータの負荷に繋る位
置に移動するようにした構成を有し、型開閉、射出の高
応答が必要な動作は、一旦アキュムレークに蓄圧して流
量調整弁により制御すると共に、応答速度を必要としな
い可塑化時のみパワーマツチ式油圧回路を用いるように
したパワーマツチ式アキュムレータ回路を提供せんとす
るものである。The present invention was proposed in order to eliminate the above-mentioned conventional drawbacks, and includes a control circuit that combines an accumulator and a flow rate regulating valve to control mold opening/closing operation and injection operation, and a control circuit that controls pressurized oil from a variable hydraulic pump. It includes a circuit for accumulating pressure in the accumulator, and a flow rate control valve provided on a circuit branching from the circuit to a hydraulic motor for rotating the screw, and the flow rate control valve has a pilot boat, and the boat controls the flow rate. When the control valve is not operating, it is in a position that cuts off the circuit that supplies pressure oil from the hydraulic pump to the hydraulic motor, and when the flow rate control valve is operating, it moves to a position that connects to the load of the hydraulic motor. For operations that require high response such as mold opening/closing and injection, pressure is stored in the accumulation rake and controlled by a flow rate adjustment valve, and a power match type hydraulic circuit is used only during plasticization, which does not require response speed. It is an object of the present invention to provide a power match type accumulator circuit as described above.
以下本発明の実施例を図面について説明すると、第２図
は本発明の実施例を示すパワーマツチ式アキュムレータ
回路の回路図で、図中１は型開閉シリンダ、２は射出シ
リンダ、３はスクリュ、４は油圧モータ、５は可変油圧
ポンプ、８．９は電磁切換弁、１０はバルブであり、こ
れらは前記第１図の回路と同じである。An embodiment of the present invention will be explained below with reference to the drawings. Fig. 2 is a circuit diagram of a power match type accumulator circuit showing an embodiment of the present invention, in which 1 is a mold opening/closing cylinder, 2 is an injection cylinder, 3 is a screw, and 4 is a circuit diagram of a power match type accumulator circuit showing an embodiment of the present invention. 1 is a hydraulic motor, 5 is a variable hydraulic pump, 8.9 is an electromagnetic switching valve, and 10 is a valve, which are the same as the circuit shown in FIG. 1 above.
第２図で第１図と相違する点は、可変油圧ポンプ５から
油圧モータ４に至る回路１３上に比例制御弁又はマニュ
アル流量制御弁１４を設けた点であり、可変油圧ポンプ
５から電磁切換弁８．９Ｇこ至る前記回路１３から分岐
した回路１’ ３ ａ上に、逆止弁１５と、比例流量弁
又はサーボ弁１６を設け、更にアキュムレータ１８を設
けた点である。The difference between FIG. 2 and FIG. 1 is that a proportional control valve or a manual flow control valve 14 is provided on the circuit 13 leading from the variable hydraulic pump 5 to the hydraulic motor 4, and an electromagnetic switching valve is provided from the variable hydraulic pump 5 to the hydraulic motor 4. A check valve 15, a proportional flow valve or a servo valve 16, and an accumulator 18 are provided on the circuit 1' 3a branched from the circuit 13 leading to the valve 8.9G.
１７は前記制御弁１４に設けられたパイロ・ノドボート
である。Reference numeral 17 denotes a pyro-node boat provided in the control valve 14.
また前記逆止弁１５と比例流量弁又はサーボ弁１６間の
回路１３ａから分岐した回路１３ｂ上Ｇこは、アキュム
レータ１８が設けられている。１９は可変油圧ポンプ５
を保護する安全弁、２０は圧力スイノチ２１によりオン
、オフ制御されてアキュムレータ１８の蓄圧の制御を行
なう電磁切換弁である。Further, an accumulator 18 is provided on a circuit 13b branched from the circuit 13a between the check valve 15 and the proportional flow valve or servo valve 16. 19 is variable hydraulic pump 5
A safety valve 20 is an electromagnetic switching valve that is turned on and off by a pressure switch 21 to control the accumulation of pressure in the accumulator 18.
次に第２図の実施例について作用を説明する。Next, the operation of the embodiment shown in FIG. 2 will be explained.
先ず型開閉シリンダ１、射出シリンダ２の動作について
説明すると、可変油圧ポンプ５からの圧油は、最大吐出
量で一旦、アキュムレータ１８に蓄圧され、この蓄圧さ
れた圧油は吐出されて比例流量弁又はサーボ弁１６を通
って流量制御され、電磁切換弁９を介して型開閉シリン
ダ１に送られ、型開閉動作の制御を行ない、また電磁切
換弁８を介して射出シリンダ２に送られ、射出動作の制
御を行なう。またアキュムレータ１８への蓄圧の制御は
、圧力スイッチ２１の信号で電磁切換弁２０をオン、オ
フして行なう。First, the operations of the mold opening/closing cylinder 1 and the injection cylinder 2 will be explained. Pressure oil from the variable hydraulic pump 5 is temporarily accumulated in the accumulator 18 at the maximum discharge amount, and this accumulated pressure oil is discharged to the proportional flow valve. Alternatively, the flow rate is controlled through the servo valve 16 and sent to the mold opening/closing cylinder 1 via the electromagnetic switching valve 9 to control the mold opening/closing operation, and also sent to the injection cylinder 2 via the electromagnetic switching valve 8 for injection. Controls operations. Further, the pressure accumulation in the accumulator 18 is controlled by turning on and off the electromagnetic switching valve 20 in response to a signal from the pressure switch 21.
図示の如く比例制御弁又はマニュアル流量制御弁１４が
動作していない時の可変油圧ポンプ５の吐出量は、パイ
ロットボート１７を有する比例制御弁又はマニュアル流
量制御弁１４を介し、ポンプ吐出圧をパイロットとじて
、バルブ１０を左方に押している。また可変油圧ポンプ
５の吐出量制御用のバイロフト圧は、バルブ１０を介し
てタンク２２に開放され、吐出量は最大となる。As shown in the figure, the discharge amount of the variable hydraulic pump 5 when the proportional control valve or manual flow control valve 14 is not operating is controlled by controlling the pump discharge pressure by piloting the proportional control valve or manual flow control valve 14 having a pilot boat 17. and pushing the valve 10 to the left. Further, the biloft pressure for controlling the discharge amount of the variable hydraulic pump 5 is released to the tank 22 via the valve 10, and the discharge amount is maximized.
次に油圧モータ４の動作について説明する。比例制御弁
又はマニュアル流量制御弁１４が動作すると、パイロッ
トポート１７は、油圧モータ４の負荷に繋がり、負荷に
応じた圧力、流量で、油圧モータ４の回転数が制御され
る。Next, the operation of the hydraulic motor 4 will be explained. When the proportional control valve or manual flow rate control valve 14 operates, the pilot port 17 is connected to the load of the hydraulic motor 4, and the rotation speed of the hydraulic motor 4 is controlled at a pressure and a flow rate according to the load.
以上詳細に説明した如く本発明は、アキュムレータに繋
がる回路及びアキュムレータと流量制御弁を組合せてな
る回路を設けたので、型開閉、射出の高応答が必要な動
作の場合は、一旦アキュムレータに蓄圧し、同アキュム
レータより吐出される圧油を前記流量調整弁の制御によ
り型開閉シリンダ及び射出シリンダに供給し、高速応答
が可能である。As explained in detail above, the present invention is provided with a circuit connected to the accumulator and a circuit combining the accumulator and the flow rate control valve. Therefore, in the case of operations that require high response such as mold opening/closing and injection, pressure is temporarily accumulated in the accumulator. Pressure oil discharged from the accumulator is supplied to the mold opening/closing cylinder and the injection cylinder under the control of the flow rate regulating valve, thereby enabling high-speed response.
また応答速度を必要としない可塑化時のみ、流量制御弁
が動作し、同制御弁のパイロットボートを介して可変油
圧ポンプの圧油が油圧モータに送られ、負荷に応じた圧
力、流量で同油圧モータの回転数を制御する。従って本
発明によると型開閉、射出の際の応答速度が早く、しか
も省エネとポンプの長寿命化を図ることができる効果が
ある。In addition, only during plasticization, which does not require response speed, the flow control valve operates, and the pressure oil of the variable hydraulic pump is sent to the hydraulic motor via the pilot boat of the control valve, with the same pressure and flow rate depending on the load. Controls the rotation speed of the hydraulic motor. Therefore, according to the present invention, the response speed during mold opening/closing and injection is fast, and it is also effective in saving energy and extending the life of the pump.
第１図は従来の射出成形機における油圧回路図、第２図
は本発明の実施例を示すパワーマツチ式アキュムレータ
回路図である。
図の主要部分の説明
１−型開閉シリンダ
２・−射出シリンダ ３−・−スクリュ４−油圧モータ
５−・−可変油圧ポンプ８．９−電磁切換弁 １０−
バルブ
１３．１３ａ、１３ｂ−−回路
１４・・−比例制御弁又はマニュアル流量制御弁（流量
制御弁）
１６・・−比例流量弁又はサーボ弁（流量調整弁）１７
・−パイロットボート
２〇−電磁切換弁 ２１−圧力スイッチ特許出願人 三
菱重工業株式会社FIG. 1 is a hydraulic circuit diagram of a conventional injection molding machine, and FIG. 2 is a power match type accumulator circuit diagram showing an embodiment of the present invention. Explanation of the main parts of the diagram 1-Type opening/closing cylinder 2--Injection cylinder 3--Screw 4-Hydraulic motor 5--Variable hydraulic pump 8.9-Solenoid switching valve 10-
Valves 13.13a, 13b -- Circuit 14 -- Proportional control valve or manual flow control valve (flow control valve) 16 -- Proportional flow valve or servo valve (flow rate adjustment valve) 17
・-Pilot boat 20-Solenoid switching valve 21-Pressure switch Patent applicant Mitsubishi Heavy Industries, Ltd.
Claims (1)
射出動作の制御を行なう夫々の制御回路と、可変油圧ポ
ンプからの圧油を前記アキュムレータに蓄圧する回路と
、同回路から分岐したスクリュ回転用の油圧モータに至
る回路上に設けられた流量制御弁とを備え、同流量制御
弁はパイロットポートを有し、同ボートは前記流量制御
弁が動作していない時は前記油圧モータに前記油圧ポン
プから圧油を送る回路を遮断する位置にあり、同流量制
御弁が動作すると前記油圧モータの負荷に繋る位置に移
動するようにしたことを特徴とするパワーマツチ式アキ
ュムレータ回路。A control circuit that combines an accumulator and a flow rate adjustment valve to control the mold opening/closing operation and injection operation, a circuit that accumulates pressure oil from the variable hydraulic pump in the accumulator, and a hydraulic pressure branched from the circuit for screw rotation. a flow control valve provided on a circuit leading to the motor, the flow control valve having a pilot port, and when the flow control valve is not operating, the boat receives pressure from the hydraulic pump to the hydraulic motor. A power match type accumulator circuit, characterized in that the circuit is located at a position that cuts off a circuit for supplying oil, and moves to a position where it is connected to the load of the hydraulic motor when the flow rate control valve is operated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3294284A JPS60176737A (en) | 1984-02-23 | 1984-02-23 | Power match type accumulator circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3294284A JPS60176737A (en) | 1984-02-23 | 1984-02-23 | Power match type accumulator circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS60176737A true JPS60176737A (en) | 1985-09-10 |
Family
ID=12373000
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3294284A Pending JPS60176737A (en) | 1984-02-23 | 1984-02-23 | Power match type accumulator circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60176737A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0367139A2 (en) * | 1988-11-01 | 1990-05-09 | Cincinnati Milacron Inc. | Injection moulding machine and method of regulating the clamping force of an injection moulding machine |
| EP0464286A2 (en) * | 1990-01-19 | 1992-01-08 | Cincinnati Milacron Inc. | Injection moulding machine with electro-hydraulic control means |
| US5355676A (en) * | 1990-10-11 | 1994-10-18 | Nissan Motor Company, Ltd. | Hydraulic pressure supply apparatus |
| EP1287968A2 (en) * | 2001-08-30 | 2003-03-05 | Mitsubishi Heavy Industries, Ltd. | Injection molding machine, hydraulic actuating mechanism of injection molding machine, and control method therefor |
| WO2018194121A1 (en) * | 2017-04-19 | 2018-10-25 | キョーラク株式会社 | Molding machine |
| JP2018176645A (en) * | 2017-04-19 | 2018-11-15 | キョーラク株式会社 | Molding machine, and method for producing foam molded body |
| CN109183568A (en) * | 2018-08-28 | 2019-01-11 | 柳工无锡路面机械有限公司 | A kind of novel energy-conserving road roller power matching system |
-
1984
- 1984-02-23 JP JP3294284A patent/JPS60176737A/en active Pending
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0367139A2 (en) * | 1988-11-01 | 1990-05-09 | Cincinnati Milacron Inc. | Injection moulding machine and method of regulating the clamping force of an injection moulding machine |
| EP0464286A2 (en) * | 1990-01-19 | 1992-01-08 | Cincinnati Milacron Inc. | Injection moulding machine with electro-hydraulic control means |
| US5355676A (en) * | 1990-10-11 | 1994-10-18 | Nissan Motor Company, Ltd. | Hydraulic pressure supply apparatus |
| EP1287968A2 (en) * | 2001-08-30 | 2003-03-05 | Mitsubishi Heavy Industries, Ltd. | Injection molding machine, hydraulic actuating mechanism of injection molding machine, and control method therefor |
| EP1287968A3 (en) * | 2001-08-30 | 2003-08-06 | Mitsubishi Heavy Industries, Ltd. | Injection molding machine, hydraulic actuating mechanism of injection molding machine, and control method therefor |
| WO2018194121A1 (en) * | 2017-04-19 | 2018-10-25 | キョーラク株式会社 | Molding machine |
| JP2018176645A (en) * | 2017-04-19 | 2018-11-15 | キョーラク株式会社 | Molding machine, and method for producing foam molded body |
| US11241810B2 (en) | 2017-04-19 | 2022-02-08 | Kyoraku Co., Ltd. | Molding machine |
| CN109183568A (en) * | 2018-08-28 | 2019-01-11 | 柳工无锡路面机械有限公司 | A kind of novel energy-conserving road roller power matching system |
| CN109183568B (en) * | 2018-08-28 | 2021-01-12 | 柳工无锡路面机械有限公司 | Novel energy-saving road roller power matching system |
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