EP0496882A1 - Controleur de charge exterieure de presse - Google Patents

Controleur de charge exterieure de presse Download PDF

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Publication number
EP0496882A1
EP0496882A1 EP90910945A EP90910945A EP0496882A1 EP 0496882 A1 EP0496882 A1 EP 0496882A1 EP 90910945 A EP90910945 A EP 90910945A EP 90910945 A EP90910945 A EP 90910945A EP 0496882 A1 EP0496882 A1 EP 0496882A1
Authority
EP
European Patent Office
Prior art keywords
hydraulic
pressure
slide
hydraulic chamber
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.)
Withdrawn
Application number
EP90910945A
Other languages
German (de)
English (en)
Other versions
EP0496882A4 (en
Inventor
Hidemi Moriyama
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Komatsu Ltd
Original Assignee
Komatsu Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Komatsu Ltd filed Critical Komatsu Ltd
Publication of EP0496882A1 publication Critical patent/EP0496882A1/fr
Publication of EP0496882A4 publication Critical patent/EP0496882A4/en
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
    • B30B15/16—Control arrangements for fluid-driven presses
    • B30B15/22—Control arrangements for fluid-driven presses controlling the degree of pressure applied by the ram during the pressing stroke
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
    • B30B15/28—Arrangements for preventing distortion of, or damage to, presses or parts thereof
    • B30B15/281—Arrangements for preventing distortion of, or damage to, presses or parts thereof overload limiting devices
    • B30B15/284—Arrangements for preventing distortion of, or damage to, presses or parts thereof overload limiting devices releasing fluid from a fluid chamber subjected to overload pressure

Definitions

  • This invention relates to an outer load control device for a double-acting mechanical press.
  • a hydraulic chamber provided at a point of an outer slide is connected to a hydraulic chamber of a hydroblank holder, and a pressure of an air chamber of the hydroblank holder is controlled by an air regulator to thereby control the pressure of the hydraulic chamber at said point and that of the hydraulic chamber of said hydroblank holder.
  • An object of the present invention is to provide an outer load control device for a press which can obtain a high precision in regulating pressure and which has an improved responsiveness.
  • an outer load control device for a double-acting mechanical press provided with an inner slide and an outer slide, comprising a logic valve connected between a hydraulic chamber of a hydraulic cylinder provided at each point of said outer slide and an overload protector and having a relief function with respect to the overload, and a servo valve controlled in response to a point generation load calculated every down position of said inner slide, wherein the hydraulic pressure in said hydraulic chamber is variably controlled by said servo valve.
  • the point load of the outer slide is controlled according to the stroke position of the inner slide, and the hydraulic pressure of the hydraulic chamber is directly controlled under the state in which a portion between the hydraulic chamber provided at the point of the outer slide and the overload protector is shut off. Therefore, the pressure regulation with high precision can be made and the responsiveness is also improved.
  • points 2 are provided in plural, for example, four places, each of these points 2 being provided with a hydraulic cylinder 3.
  • a piston 3a received in each hydraulic cylinder 3 is connected to a plunger 3b, and a driving force from an outer slide driving mechanism not shown is transmitted to the outer slide 1 through the plunger 3b and hydraulic pressure in a hydraulic chamber 3c of the hydraulic cylinder 3.
  • the hydraulic chamber 3c of the hydraulic chamber 3 is connected to a hydraulic chamber 6a of an overload protector 6 through a line 4 and a logic valve 5.
  • the logic valve 5 has a valve body 5b urged in a closing direction by a compression spring 5a. Pressure of the line 4 is introduced toward the spring chamber 5b through a pilot line 7 and a solenoid valve 8, and an overload relief valve 9 is provided between the spring chamber 5b and the solenoid valve 8 so that at the time of overload, pressure in the spring chamber 5b is drained to a tank 10.
  • the overload protector 6 has a hydraulic chamber 6a and an air pressure chamber 6b having a larger area than that of the hydraulic chamber 6a. These hydraulic chamber 6a and the air pressure chamber 6b house therein pistons 6d and 6e, respectively, connected by a piston rod 6c. Air of constant pressure is supplied from an air source 12 to the air pressure chamber 6b through an air regulator 13 and an air tank 14, and the interior of the hydraulic chamber 6a is pressurized by said air pressure through the pistons 6d and 6e.
  • a pressure sensor 15 and a servo valve 16 are connected halfway of the line 4 which connects between the hydraulic chamber 3c of the hydraulic cylinder 3 and the logic valve 5.
  • the pressure chamber 15 detects pressure within the hydraulic chamber 3c to output a detected value to a control device 17, and the servo valve 16 is controlled by the control device 17 so as to control hydraulic pressure supplied from a hydraulic pump 18 to the hydraulic chamber 3c through a line 19.
  • a preload switching valve 20 which switches a preload pressure supplied to the hydraulic chamber 3c into two stages, a high pressure and a low pressure, is connected to a discharge side of the hydraulic pump 18, and an accumulator 23 is connected to a downstream side of a check valve 21 through a solenoid valve 22.
  • reference numeral 25 designates an operating oil pump for supplying an operating pressure to the servo valve 16; 26, a cooling pump for cooling an operating oil in the tank 10; 27, a limit switch mounted in the vicinity of the plunge 3b to detect a stroke lmit of the outer slide 1; and 28, a limit switch for detecting a hydrozone.
  • reference numeral 30 designates a balancer for urging the outer slide 1 upwardly
  • 31 designates a mold mounted on the outer slide 1.
  • Load patterns R1 to R1 with respect to a stroke s of the inner slide are set as set values in the control device 17.
  • a stroke of the inner slide, air pressure in the air pressure chamber 6b of the overload protector 6 and the balancer 30, and a balancer raising force r at the bottom dead center of the slide are inputted from an encoder provided on a rotary cam and a stroke detector 33 such as a linear scale mounted on the inner slide.
  • the solenoid valve 8 is set to a position 8b to drain pressure in the spring chamber 5c whereby the logic valve 5 is opened to switch the preload pressure switching valve 20 to the low pressured side.
  • the servo valve 16 is set to a position 16a to set a set load to a maximum value, and the solenoid valve 22 is set to a position 22b to disconnect the accumulator 23 from the line 19.
  • Molding is carried out under this state to maximize the outer load, and the outer slide 1 can be driven.
  • the solenoid valve 8 is set to a position 8a, the logic valve 6 is closed, and the preload pressure switching valve 20 is switched to the high pressure side.
  • the solenoid valve 22 is set to a position 22a, and the accumulator 23 is connected to the line 19. Pressure of the air regulator 13 for supplying air to the air pressure chamber 6b of the overload protector 6 is set to zero.
  • the outer slide 1 When molding starts from the aforesaid state, the outer slide 1 first moves down to the bottom dead center, and a peripheral portion of the blank is held by a blank holder (not shown) on the side of the lower mold resiliently supported on a die cushion not shown.
  • control device 17 calculates point generation loads F1 to F4 at respectively points from slide weights W1 to W4 and mold weights W1 to W4 at respective points 2 by the following formula in accordance with the flow chart shown in Fig. 3.
  • F1 ⁇ 4 R1 ⁇ 4 + r/4 - W1 ⁇ 4 - w1 ⁇ 4
  • the point generation loads at respective positions of the inner slide are obtained from a value in which a slide stroke S' is corrected by the following formula from a stroke S of the inner slide and the number of revolutions N of a main motor.
  • S' S - kN (K is a proportional constant.)
  • the point loads at the respective positions of the inner slide obtained as described above are amplified by an amplifier and sent to the servo valve 16. Hydraulic pressure in the hydraulic chamber 3c of the hydraulic cylinder 3 is controlled by the servo valve 16, and hydraulic pressure in the hydraulic chamber 3c is detected by the pressure sensor 15 and fed back to the control device 17.
  • the overload relief valve 9 When an overload occurs in the outer slide 1 during operation, the overload relief valve 9 is relived so that the logic valve 5 is opened.
  • the hydraulic pressure in the hydraulic chamber 3c is drained from the logic valve 5 to thee overload protector 6 to avoid overload. Since the pressure sensor 15 detects that the hydraulic pressure in the hydraulic chamber 3c abnormally lowers, the servo valve 16 is switched from the position 16a to 16b, and the hydraulic pressure within the hydraulic chamber 3c is drained to the tank 10.
  • the hydrozone detecting limit switch 28 detects this error during operation to give an alarm.
  • the stroke limit detecting limit switch 27 also gives an alarm when an abnormal condition occurs in the hydraulic system or when the adjustment of die height is erroneous.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Control Of Presses (AREA)
  • Press Drives And Press Lines (AREA)

Abstract

Contrôleur de charge extérieure d'une presse visant à obtenir une précision élevée de la régulation de la pression et à améliorer la sensibilité de fonctionnement. Ledit contrôleur comprend une vanne logique (5) laquelle est connectée entre la chambre hydraulique (3c) d'un cylindre hydraulique (3) disposée au niveau de chaque point (2) d'une coulisse extérieure (1), ainsi qu'un dispositif de protection de surcharge (6), et laquelle a une fonction de libération en cas de surcharge, ainsi qu'une servo-vanne (16) commandée en fonction d'une charge de pointe calculée à chaque position de descente de la coulisse. La pression d'huile à l'intérieur de la chambre hydraulique est commandée de manière variable par la servo-vanne se trouvant dans ledit contrôleur.
EP19900910945 1989-07-14 1990-07-13 Outer load controller of press Withdrawn EP0496882A4 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP180598/89 1989-07-14
JP1180598A JPH0763879B2 (ja) 1989-07-14 1989-07-14 プレスのアウタ荷重制御装置

Publications (2)

Publication Number Publication Date
EP0496882A1 true EP0496882A1 (fr) 1992-08-05
EP0496882A4 EP0496882A4 (en) 1992-11-04

Family

ID=16086061

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19900910945 Withdrawn EP0496882A4 (en) 1989-07-14 1990-07-13 Outer load controller of press

Country Status (5)

Country Link
EP (1) EP0496882A4 (fr)
JP (1) JPH0763879B2 (fr)
KR (1) KR920703323A (fr)
BR (1) BR9007524A (fr)
WO (1) WO1991001215A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2840381A1 (fr) * 2002-06-04 2003-12-05 Linde Ag Systeme d'entrainement hydrostatique, notamment pour un chariot transport

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3534326B2 (ja) * 1994-11-29 2004-06-07 株式会社小松製作所 油圧プレスのスライド制御方法
JP2011038615A (ja) * 2009-08-17 2011-02-24 Sumitomo Heavy Industries Techno-Fort Co Ltd 機械プレスにおける湿式クラッチブレーキの冷却油量制御装置
CN103331937A (zh) * 2013-07-04 2013-10-02 天津市天锻压力机有限公司 基于压力反馈的数控液压机泄压系统

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60261698A (ja) * 1984-06-07 1985-12-24 Toyota Motor Corp プレスのアウタ荷重制御方法およびその装置
JPS6246198U (fr) * 1985-09-02 1987-03-20
JPS62151300A (ja) * 1985-12-26 1987-07-06 Komatsu Ltd プレス機械の過荷重保護装置

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9101215A1 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2840381A1 (fr) * 2002-06-04 2003-12-05 Linde Ag Systeme d'entrainement hydrostatique, notamment pour un chariot transport

Also Published As

Publication number Publication date
EP0496882A4 (en) 1992-11-04
KR920703323A (ko) 1992-12-17
JPH0347700A (ja) 1991-02-28
BR9007524A (pt) 1992-06-23
JPH0763879B2 (ja) 1995-07-12
WO1991001215A1 (fr) 1991-02-07

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