JPS6114026A - Die cushion device - Google Patents

Die cushion device

Info

Publication number
JPS6114026A
JPS6114026A JP59134527A JP13452784A JPS6114026A JP S6114026 A JPS6114026 A JP S6114026A JP 59134527 A JP59134527 A JP 59134527A JP 13452784 A JP13452784 A JP 13452784A JP S6114026 A JPS6114026 A JP S6114026A
Authority
JP
Japan
Prior art keywords
force
work
cushion
holder
pressure reducing
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
Application number
JP59134527A
Other languages
Japanese (ja)
Inventor
Naoki Teramoto
直樹 寺本
Katsuyuki Onoki
小野木 勝之
Akiyasu Taguchi
田口 彰康
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.)
IHI Corp
Original Assignee
IHI Corp
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 IHI Corp filed Critical IHI Corp
Priority to JP59134527A priority Critical patent/JPS6114026A/en
Publication of JPS6114026A publication Critical patent/JPS6114026A/en
Pending legal-status Critical Current

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D24/00Special deep-drawing arrangements in, or in connection with, presses
    • B21D24/02Die-cushions

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Presses And Accessory Devices Thereof (AREA)
  • Shaping Metal By Deep-Drawing, Or The Like (AREA)

Abstract

PURPOSE:To provide the titled die cushion device preventing the generation of the local excessive distortion, fold, crack, etc. of a work with reducing the work holding force at the last forming stage by constituting so as to reduce the die cushion force for a work to the preset capability in accordance with the cushion stroke. CONSTITUTION:The peripheral part of a work 4 is held between a descending upper die 1 and work holder 5 and the holder 5 is moved from the initial forming position A to the last forming position B by the descent of the upper die 1 and the position signal for the while is transmitted minutely to an arithmetic commander 32. The commander 32 operates the position signal and set value, transmits a cushion force reducing command signal to a pressure reducing valve 22 and the coil pressure reducing force is acted on a cylinder body 10 so as to reduce the cushion force of an air cylinder 9. The oil pressure reducing force thereof leaves the work holding force in case of the value being not exceeding the cushion force of the cylinder 9, and by selecting adequately the set value of the commander 32 the work holding force can be reduced according to the movement of the holder 5 as per an alternate long and short dash line shown in the figure, for instance.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、プレス装置にて、ワークを絞り加工する際に
発生するワークの局部歪、しわ、亀裂等を11jl衝す
るためのダイクッション装置に関するものである。
[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a die cushion device for eliminating local strains, wrinkles, cracks, etc. of a workpiece that occur when the workpiece is drawn using a press machine. It is related to.

〔従来の技術〕[Conventional technology]

例えば、自動車ボディのパネル材等をプレス加工により
成形するためのプレス装置の要部を第5図に示すと、1
は図示しない駆動装置によって上下方向のスライドスト
ロークを与えられた上型(アッパダイ)、2はベースフ
レーム3上に固定した下型(ロアダイ)であり、該下型
2の外周方部には、下型2の上部位置にてワーク4をセ
ットし且つ上型1との間でワーク4の周縁部を挾持して
ワーク4にプレス加工時の成形張力を付与するためのワ
ークホルダー5が配設されている。又、ベースフレーム
3の下面側位置には、ホルダー基板6が設けられ、該ホ
ルダー基板6土には、ベースフレーム3を移動可能に責
通ずる適数本のロッド7が立設され、該ロッド7の上端
がワークホルダー5に接続されている。
For example, Fig. 5 shows the main parts of a press machine for forming automobile body panel materials etc. by press working.
2 is an upper die (upper die) which is given a sliding stroke in the vertical direction by a drive device (not shown); 2 is a lower die (lower die) fixed on the base frame 3; A work holder 5 is provided for setting the work 4 at the upper position of the mold 2 and clamping the peripheral edge of the work 4 between it and the upper mold 1 to apply forming tension to the work 4 during press working. ing. Further, a holder substrate 6 is provided at a position on the lower surface side of the base frame 3, and an appropriate number of rods 7 for movably connecting the base frame 3 are erected on the holder substrate 6. The upper end of is connected to the work holder 5.

今、図示しない駆動装置によって上型1に上下方向のス
トローク動を与え、上型1が成形初期位MA、まで下降
すると、上型1とブークホルダー5との間にワーク4の
周縁部が挾持され、更に上型1とワークホルダー5とが
一体になって成形末期位置B・まで下降し、第6図に示
すように上型1と下型2どの間でワーク4がプレス加工
される。
Now, when the upper mold 1 is given a stroke movement in the vertical direction by a drive device (not shown) and the upper mold 1 is lowered to the initial molding position MA, the peripheral edge of the workpiece 4 is clamped between the upper mold 1 and the book holder 5. Then, the upper mold 1 and the work holder 5 are lowered together to the final molding position B, and the work 4 is pressed between the upper mold 1 and the lower mold 2 as shown in FIG.

師かるプレス絞り加工時にワークの周囲を挟持しワーク
に成形張力を付与するために、従来は、ホルダー基板6
の下部にエアタンク8と接続されたエアシリンダ9が設
けられている。図示の場合、シリンダ胴10がホルダー
基板6に、ピストン11が装置本体フレーム13に夫々
固定されている。尚12はピストン11に設けられたエ
ア通路である。従って、ワークホルダー5は、成層初期
位置Aから成形末期位置Bまでの間では、常にエアシリ
ンダ9によりダイクッション力が与えられている。そし
てプレス加工終了時には、第7図に示すようにワーク4
を下型2の上部位置へ押上げることができる。
Conventionally, a holder substrate 6 is used to clamp the periphery of the workpiece and apply forming tension to the workpiece during press drawing.
An air cylinder 9 connected to an air tank 8 is provided at the bottom of the air cylinder 9 . In the illustrated case, the cylinder body 10 is fixed to the holder base plate 6, and the piston 11 is fixed to the apparatus main body frame 13, respectively. Note that 12 is an air passage provided in the piston 11. Therefore, the die cushion force is always applied to the work holder 5 by the air cylinder 9 from the initial layering position A to the final forming position B. At the end of the press process, the workpiece 4 is shown in Figure 7.
can be pushed up to the upper position of the lower mold 2.

しかしながら、斯かる従来方式においては、エアシリン
ダ9へのエア供給はエアタンク8によって与えられてい
るため、ワークホルダー5が成形初期位置Aから成形末
期位置Bまで移動(クッションストローク移動)する際
に、ワークホルダー5には、第4図の実線で示すように
、クッション力が上り勾配をもった直線的なワーク保持
力として付必されることになる。ワーク4の成形性を良
好なものとするには、ワーク4に亀裂を発生させないこ
とは勿論のこと、偏肉を発生させないことであるが、前
記したように、ワークホルダー5のワーク保持力が直線
的に上がると言うことは、成形末期にワーク4に最も大
きな張力が作用することであり、良好な成形を印書する
原因となる。
However, in such a conventional method, since air is supplied to the air cylinder 9 by the air tank 8, when the work holder 5 moves from the initial molding position A to the final molding position B (cushion stroke movement), As shown by the solid line in FIG. 4, the work holder 5 is provided with a cushioning force as a linear work holding force with an upward slope. In order to improve the formability of the workpiece 4, it is necessary not only to prevent cracks from occurring in the workpiece 4 but also to prevent uneven thickness, but as mentioned above, the workpiece holding force of the workpiece holder 5 is The linear increase means that the greatest tension is applied to the workpiece 4 at the final stage of molding, which causes good molding to be printed.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

本発明は、ダイクッション力を、クッションストローク
に応じ予め設定した能力に減少させ、ワークの局部過大
歪、しわ、亀裂等の発生を防止して成形性を向上させる
ものである。
The present invention reduces the die cushion force to a preset capacity according to the cushion stroke, thereby preventing the occurrence of local excessive strain, wrinkles, cracks, etc. in the workpiece, thereby improving formability.

〔問題点を解決するための手段〕          
   7本発明のダイクッション装置゛は、ワークホル
ダーにクッション力を与えるエアシリンダに油圧シリン
ダを連結し、且つ該油圧シリンダに電磁比例式減圧弁を
介し圧油供給装置を接続し、前記減圧弁をワークホルダ
ーのクッションストロークに対応して制御するようにし
た構成を有する。
[Means for solving problems]
7. The die cushion device of the present invention connects a hydraulic cylinder to an air cylinder that applies a cushioning force to a work holder, and connects a pressure oil supply device to the hydraulic cylinder via an electromagnetic proportional pressure reducing valve, and connects the pressure reducing valve to the hydraulic cylinder. It has a configuration in which control is performed in response to the cushion stroke of the work holder.

〔作   用〕[For production]

従って、ダイクッション力を予め設定した能力に減少さ
せ、ワーク周囲を挾持する力を弱められる。
Therefore, the die cushion force can be reduced to a preset capacity, and the force for clamping around the workpiece can be weakened.

〔実 施 例〕〔Example〕

以下、図面を参照して本発明の詳細な説明する。 Hereinafter, the present invention will be described in detail with reference to the drawings.

本発明は、第5図で示したようなダイクッション装置を
備えたプレス装置において、エアシリンダ9によるダイ
クッション力を油圧引下刃によって減少させるようにし
たものである。
The present invention is a press apparatus equipped with a die cushion device as shown in FIG. 5, in which the die cushion force exerted by the air cylinder 9 is reduced by a hydraulic pull-down blade.

即ち、第1図に示すように、エアシリンダ9の下部に油
圧シリンダ14を同心状に配置して、・  該油圧シリ
ンダ14のシリンダ胴15をエアシリンダ9のピストン
11下面に油密に取付けると共に、ピストンロッド16
の先端をピストン11を移動可能に貫通させてシリンダ
胴10に連結し、更に該油圧シリンダ14のピストンロ
ッド引込み室17に油圧制御装置18からの配管19を
接続する。
That is, as shown in FIG. 1, the hydraulic cylinder 14 is arranged concentrically under the air cylinder 9, and the cylinder body 15 of the hydraulic cylinder 14 is oil-tightly attached to the lower surface of the piston 11 of the air cylinder 9. , piston rod 16
The distal end of the piston 11 is movably passed through the piston 11 and connected to the cylinder body 10, and the piping 19 from the hydraulic control device 18 is connected to the piston rod retraction chamber 17 of the hydraulic cylinder 14.

油圧制御装置18には高圧アキュムレータ20があり、
該アキュムレータ20に接続した配管21と油圧シリン
ダ14に接続した配管19との間には電磁比例式減圧弁
22を備えた圧油供給管23が設けである。前記減圧弁
22には、ワークホルダー5の移動位置信号と設定値と
を演算指令器32tこで演算して得られた指令信号が送
られるようになっている。尚、IiI記位前位置信号出
はワークホルダー5の移動位置を屓接検出してもよいが
、シリンダ胴10の移動位置、上型1の移動位置、上型
1の駆動装置等から採取してもよい。又、圧油供給管2
3より更にタンク24f11位置の配管19と配管21
との間には圧油戻り管25が設けてあり、該戻り管25
には絞−リ26と逆止弁33を備えている。
The hydraulic control device 18 includes a high pressure accumulator 20;
A pressure oil supply pipe 23 equipped with an electromagnetic proportional pressure reducing valve 22 is provided between a pipe 21 connected to the accumulator 20 and a pipe 19 connected to the hydraulic cylinder 14. A command signal obtained by calculating the movement position signal of the work holder 5 and a set value by a calculation command unit 32t is sent to the pressure reducing valve 22. Note that the IiI pre-positioning position signal may be output by directly detecting the moving position of the work holder 5, but it may also be obtained from the moving position of the cylinder body 10, the moving position of the upper mold 1, the driving device of the upper mold 1, etc. It's okay. Also, pressure oil supply pipe 2
Further from 3, pipe 19 and pipe 21 at tank 24f11 position
A pressure oil return pipe 25 is provided between the return pipe 25 and
is equipped with a throttle 26 and a check valve 33.

尚、27は毅り、28は冷却器、29はリリ°−フ弁、
30は逆止弁、31はポンプ、34はモータである。 
・斯かる構成としであるので、上型1が下降してきて上
型1とワークホルダー5とでワーク4の周縁部を挾持し
、更に下降してワークホルダー5が成形初期位置Aから
成形末期位置Bまで移動すると、その間の位置信号が逐
一演算指令器32へ送られる。演算指令器32ではこの
位置信号と設定値とを演算し、減圧弁22ヘクッション
力減圧指令信号を送る。減圧弁22が演算指令器32の
指令に基づいて作動すると、アキュムレー・り20から
の圧油が配管21、供給管23、配管19を経て油圧シ
リンダ14内のピストンロッド引込み室17に送られる
。これによって、ピストンロッド16はシリンダ胴15
内に引込まれるので、エアシリンダ9のクッション力を
減少させるようシリンダ胴10に油圧用下方が作用する
In addition, 27 is Takeshi, 28 is a cooler, 29 is a relief valve,
30 is a check valve, 31 is a pump, and 34 is a motor.
- With this configuration, the upper die 1 descends, the upper die 1 and the work holder 5 clamp the peripheral edge of the work 4, and then descends further to move the work holder 5 from the initial molding position A to the final molding position. When the robot moves to B, the position signals during that time are sent to the calculation command unit 32 one by one. The calculation command unit 32 calculates this position signal and the set value, and sends a cushion force reduction command signal to the pressure reduction valve 22. When the pressure reducing valve 22 operates based on a command from the arithmetic command unit 32, pressure oil from the accumulator 20 is sent to the piston rod retraction chamber 17 in the hydraulic cylinder 14 via the piping 21, the supply pipe 23, and the piping 19. With this, the piston rod 16 is moved to the cylinder body 15.
Since it is drawn in, a lower hydraulic pressure acts on the cylinder body 10 to reduce the cushioning force of the air cylinder 9.

この油圧用下方は、エアシリンダ9のクッション力を越
えない値であればワーク保持力は残存し、演算指令器3
2の設定値を適宜選定しておぐことにより、ワーク保持
力を、例えば第4図の一点鎖線で示すように、ワークホ
ルダー5の移動に対応して減少させることができる。
If the lower hydraulic pressure does not exceed the cushioning force of the air cylinder 9, the workpiece holding force remains, and the calculation command unit 3
By appropriately selecting the setting value 2, the workpiece holding force can be reduced in accordance with the movement of the workpiece holder 5, as shown by the dashed line in FIG. 4, for example.

従って、第2図に示すように、ワークホルダー5が下降
して成形末期位NBに近付くにつれ、ワーク4に作用す
る成形張力が弱くなり、ワーク4の良好な成形が得られ
る。
Therefore, as shown in FIG. 2, as the work holder 5 descends and approaches the final stage of forming NB, the forming tension acting on the work 4 becomes weaker, and the work 4 can be formed favorably.

更に、ワークホルダー5が成形末期位置Bまで達した後
に上型1は上方へ移動するので、ワークホルダー5には
エアシリンダ9のクッション力が上昇力となって作用し
、第3図に示すようにワーク4を下型2の上部位置へ押
上げる。
Furthermore, since the upper die 1 moves upward after the work holder 5 reaches the final molding position B, the cushioning force of the air cylinder 9 acts on the work holder 5 as a rising force, as shown in FIG. Then, the workpiece 4 is pushed up to the upper position of the lower mold 2.

この場合、ワークホルダー5の上昇力はクッション力が
総て作用するのではなく、油圧シリンダ14による油圧
用下方との差圧であり、エアシリンダ9のシリンダJF
IIOの伸長動によって油圧シリンダ14のピストンロ
ッド16を伸長させるよう作用する。ピストンロッド1
6が伸長すると、ピストンロッド引込み室17内の圧油
は配管19側へ押出され、戻り管25の絞り26、逆止
弁33を経         繋てアキュムレータ20
へ戻される。従うて、戻り管25の絞り26の調整によ
り、ワークホルダー5の上昇速度が制御される。
In this case, the lifting force of the work holder 5 is not entirely due to the cushioning force, but is due to the differential pressure between the lower part of the hydraulic pressure from the hydraulic cylinder 14 and the cylinder JF of the air cylinder 9.
The extension movement of IIO acts to extend the piston rod 16 of the hydraulic cylinder 14. piston rod 1
6 expands, the pressure oil in the piston rod retraction chamber 17 is pushed out to the piping 19 side, and is connected to the accumulator 20 via the throttle 26 of the return pipe 25 and the check valve 33.
be returned to. Therefore, by adjusting the throttle 26 of the return pipe 25, the rising speed of the work holder 5 is controlled.

尚、本発明は前記実施例にのみ限定されるものではなく
、電磁比例式減圧弁として、二次圧力を制御する油圧サ
ーボ弁を用いてもよく、その他本発明の要旨を逸脱しな
い限り種々変更を加え得ることは勿論である。
It should be noted that the present invention is not limited to the above-described embodiments, and a hydraulic servo valve for controlling secondary pressure may be used as the electromagnetic proportional pressure reducing valve, and various other changes may be made without departing from the gist of the present invention. Of course, it is also possible to add

〔発明の効果〕〔Effect of the invention〕

以上説明したように、本発明のダイクッション装置によ
れば、クッションストロークに対応してダイクッション
力を予め設定した能力に減少させることができるので、
成形末期位置におけるワーク保持力を弱めてワークの局
部過大型、しわ、亀裂等の発生を防止し得られ、従って
ワークの成形性を向上させることができる、と言う優れ
た効果を奏し得る。
As explained above, according to the die cushion device of the present invention, the die cushion force can be reduced to a preset capacity in response to the cushion stroke.
By weakening the workpiece holding force at the final stage of molding, it is possible to prevent the workpiece from becoming locally oversized, wrinkled, cracked, etc., and therefore the moldability of the workpiece can be improved, which is an excellent effect.

【図面の簡単な説明】[Brief explanation of the drawing]

第1図は本発明のダイクッション装置を備えたプレス装
置の断面図、第2図及び第3図は第1図の作動説明図、
第4図はワークホルダーのストロークとクッション力と
の関係を示す図、第5図は従来のダイクッション装置を
備えたプレス装置の断面図、第6図及び第7図は第5図
の作動説明図である。 1は上型、2は下型、4はワーク、5はワークホルダー
、8はエアタンク、9はエアシリンダ、14は油圧シリ
ンダ、16はピストンロッド、17はピストンロッド引
込み室、18は油圧制御装置、19 、21は配管、2
0はアキュムレータ、22は電磁比例式減圧弁、23は
圧油供給管、25は戻り管を示す。 特  許  出  1  人 石川島播磨重工業株式会社 第1図 第2図    第3図
FIG. 1 is a sectional view of a press device equipped with a die cushion device of the present invention, FIGS. 2 and 3 are operation explanatory diagrams of FIG. 1,
Fig. 4 is a diagram showing the relationship between the stroke of the work holder and the cushioning force, Fig. 5 is a sectional view of a press device equipped with a conventional die cushion device, and Figs. 6 and 7 are explanations of the operation of Fig. 5. It is a diagram. 1 is an upper mold, 2 is a lower mold, 4 is a work, 5 is a work holder, 8 is an air tank, 9 is an air cylinder, 14 is a hydraulic cylinder, 16 is a piston rod, 17 is a piston rod retraction chamber, 18 is a hydraulic control device , 19, 21 are piping, 2
0 is an accumulator, 22 is an electromagnetic proportional pressure reducing valve, 23 is a pressure oil supply pipe, and 25 is a return pipe. Patent issued by 1 Ishikawajima Harima Heavy Industries Co., Ltd. Figure 1 Figure 2 Figure 3

Claims (1)

【特許請求の範囲】[Claims] 1)上型とワークホルダーとの間でワークを挾持しなが
らワークをプレス加工するようにしたプレス装置におい
て、ワークホルダーにクツシヨン力を与えるエアシリン
ダに油圧シリンダを連結し、且つ該油圧シリンダに電磁
比例式減圧弁を介し圧油供給装置を接続し、前記減圧弁
をワークホルダーのクツシヨンストロークに対応して制
御するよう構成したことを特徴とするダイクツシヨン装
置。
1) In a press device that presses a work while holding it between an upper die and a work holder, a hydraulic cylinder is connected to an air cylinder that applies cushioning force to the work holder, and an electromagnetic cylinder is connected to the hydraulic cylinder. A dictation device, characterized in that a pressure oil supply device is connected through a proportional pressure reducing valve, and the pressure reducing valve is controlled in accordance with a cushion stroke of a work holder.
JP59134527A 1984-06-29 1984-06-29 Die cushion device Pending JPS6114026A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP59134527A JPS6114026A (en) 1984-06-29 1984-06-29 Die cushion device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP59134527A JPS6114026A (en) 1984-06-29 1984-06-29 Die cushion device

Publications (1)

Publication Number Publication Date
JPS6114026A true JPS6114026A (en) 1986-01-22

Family

ID=15130399

Family Applications (1)

Application Number Title Priority Date Filing Date
JP59134527A Pending JPS6114026A (en) 1984-06-29 1984-06-29 Die cushion device

Country Status (1)

Country Link
JP (1) JPS6114026A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61190316U (en) * 1985-05-16 1986-11-27
JPS61195817U (en) * 1985-05-23 1986-12-06
US5813275A (en) * 1994-07-05 1998-09-29 Komatsu Ltd. Safety circuit for press die cushion
JP2010046716A (en) * 2008-08-25 2010-03-04 Feintool Intellectual Property Ag Method of and device for controlling the synchronization of cylinder/piston unit and for reducing pressure peak during forming and/or fineblanking on press

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61190316U (en) * 1985-05-16 1986-11-27
JPH0324243Y2 (en) * 1985-05-16 1991-05-27
JPS61195817U (en) * 1985-05-23 1986-12-06
US5813275A (en) * 1994-07-05 1998-09-29 Komatsu Ltd. Safety circuit for press die cushion
JP2010046716A (en) * 2008-08-25 2010-03-04 Feintool Intellectual Property Ag Method of and device for controlling the synchronization of cylinder/piston unit and for reducing pressure peak during forming and/or fineblanking on press

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