JPH087934Y2 - Press brake hydraulic circuit - Google Patents

Press brake hydraulic circuit

Info

Publication number
JPH087934Y2
JPH087934Y2 JP1990030950U JP3095090U JPH087934Y2 JP H087934 Y2 JPH087934 Y2 JP H087934Y2 JP 1990030950 U JP1990030950 U JP 1990030950U JP 3095090 U JP3095090 U JP 3095090U JP H087934 Y2 JPH087934 Y2 JP H087934Y2
Authority
JP
Japan
Prior art keywords
chamber
ram
pressure oil
tank
extension
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 - Lifetime
Application number
JP1990030950U
Other languages
Japanese (ja)
Other versions
JPH03126221U (en
Inventor
浩之 小島
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
Priority to JP1990030950U priority Critical patent/JPH087934Y2/en
Publication of JPH03126221U publication Critical patent/JPH03126221U/ja
Application granted granted Critical
Publication of JPH087934Y2 publication Critical patent/JPH087934Y2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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  • Bending Of Plates, Rods, And Pipes (AREA)

Description

【考案の詳細な説明】 〔産業上の利用分野〕 本考案は、長尺の板を折曲げる作業に適するプレスブ
レーキにおけるラムを上下動する油圧シリンダに圧油を
供給する油圧回路に関する。
DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a hydraulic circuit for supplying pressure oil to a hydraulic cylinder that moves a ram up and down in a press brake suitable for bending a long plate.

〔従来の技術〕[Conventional technology]

プレスブレーキとしては左右一対の油圧シリンダで上
型を備えたラムを上下動し、テーブルに設けた下型とに
よって長尺の板を折曲げる油圧式プレスブレーキが知ら
れ、その一対の油圧シリンダに圧油を供給する油圧回路
としては、例えば第2図に示すものが知られている。
As a press brake, a hydraulic press brake is known in which a ram with an upper mold is moved up and down by a pair of left and right hydraulic cylinders, and a long plate is bent by a lower mold provided on a table. As a hydraulic circuit for supplying pressure oil, for example, one shown in FIG. 2 is known.

つまり、油圧シリンダ1を第1・第2伸長室2,3と縮
少室4を有するものとし、ポンプ5の吐出圧油を電磁弁
6で第1・第2路7,8の一方に供給し、第1路7の圧油
を第1・第2サーボバルブ9,10で第1伸長室2と縮少室
4の一方に供給すると共に、第2路8の圧油を第2伸長
室3に供給するようにし、ラム高速下降時には電磁弁6
のソレノイド6aに通電して第1位置Iとすることでポン
プ5の圧油を第2伸長室3に供給すると共に、モータ11
で第1・第2サーボバルブ9,10を伸長位置Bに切換えて
油圧シリンダ1を伸長させ、第1・第2サーボバルブ9,
10の切換えストロークをモータ11でコントロールして絞
りを調整することで縮少室4内の油がタンク12に流出す
る流量を制御して速度調整及び左右油圧シリンダ1の下
降を同期してラムが平行に下降するようにしている。
That is, the hydraulic cylinder 1 has the first and second expansion chambers 2 and 3 and the reduction chamber 4, and the discharge pressure oil of the pump 5 is supplied to one of the first and second passages 7 and 8 by the solenoid valve 6. The pressure oil in the first passage 7 is supplied to one of the first extension chamber 2 and the reduction chamber 4 by the first and second servo valves 9 and 10, and the pressure oil in the second passage 8 is supplied to the second extension chamber. 3 and the solenoid valve 6 when the ram descends at high speed.
The solenoid 6a is energized to the first position I to supply the pressure oil of the pump 5 to the second extension chamber 3 and the motor 11
Switch the first and second servo valves 9 and 10 to the extension position B to extend the hydraulic cylinder 1, and the first and second servo valves 9 and 10
By controlling the switching stroke of 10 with the motor 11 and adjusting the throttle, the flow rate of the oil in the reduction chamber 4 flowing out to the tank 12 is controlled, and the ram is synchronized with the speed adjustment and the lowering of the left and right hydraulic cylinders 1. I am trying to descend in parallel.

ラム遅速下降時には電磁弁6のソレノイド6aに通電せ
ずに第2位置IIとして第2伸長室3をタンクに連通する
と共に、モータ11で第1・第2サーボバルブ9,10を伸長
位置Bとし、油圧を第1伸長室2に供給し、縮少室4内
の圧油をタンク12に流出するが、この時第1伸長室2の
容量が大で供給圧油量が不足するからフィリングバルブ
(吸込弁)13よりタンク内の圧油をラムの自重落下によ
り吸込むようになり、前述と同様にモータ11による第1
・第2サーボバルブ9,10の切換えストロークを調整して
絞りを変更することで縮少室4内の圧油がタンク12へ流
出する流量を制御して速度調整及び平行調整を行う。
When the ram slows down, the solenoid 6a of the solenoid valve 6 is not energized and the second extension chamber 3 is connected to the tank as the second position II, and the motor 11 sets the first and second servo valves 9 and 10 to the extension position B. , The hydraulic pressure is supplied to the first expansion chamber 2 and the pressure oil in the reduction chamber 4 flows out to the tank 12, but at this time the capacity of the first expansion chamber 2 is large and the amount of supplied pressure oil is insufficient, so the filling valve (Suction valve) 13 sucks the pressure oil in the tank by dropping the ram by its own weight.
By adjusting the switching stroke of the second servo valves 9 and 10 to change the throttle, the flow rate of the pressure oil in the reduction chamber 4 flowing out to the tank 12 is controlled to perform speed adjustment and parallel adjustment.

ラム上昇時には電磁弁6を第2位置IIとし、モータ11
で第1・第2サーボバルブ9,10を縮少位置Aとして縮少
室4に圧油を供給し、第1伸長室2内の圧油を第1・第
2サーボバルブ9,10を経てタンクに流出し、第2伸長室
3内の圧油を電磁弁6よりタンクに流出して油圧シリン
ダ1を縮少させてラムを上昇させる。
When the ram is raised, the solenoid valve 6 is set to the second position II and the motor 11
Then, the first and second servo valves 9 and 10 are set to the reduced position A to supply pressure oil to the reduction chamber 4, and the pressure oil in the first extension chamber 2 is passed through the first and second servo valves 9 and 10. The pressure oil in the second extension chamber 3 flows out to the tank from the electromagnetic valve 6 to the tank to reduce the hydraulic cylinder 1 and raise the ram.

〔考案が解決しようとする課題〕[Problems to be solved by the device]

かかる油圧回路であると、ラム下降時には縮少室4内
の圧油がタンクに流れる流量を第1・第2サーボバルブ
9,10で絞ることで速度調整、平行調整し、ラム上昇時に
は縮少室4内に供給される圧油の流量、圧力を第1・第
2サーボバルブ9,10で絞ることで速度調整、平行調整し
ているが、第2伸長室3内の圧油が電磁弁6よりタンク
に流出するので、ラム上昇開始時には油圧シリンダ1の
縮少室4に供給される圧力、流出が同一であっても左右
の油圧シリンダ1の摺動抵抗差などによって左右の油圧
シリンダ1の縮少速度に差が生じ、ラムが左右にフラツ
キながら上昇することがあり、ラムのガイド部などを摩
耗したりすることがあって好ましくない。
With such a hydraulic circuit, when the ram descends, the flow rate of the pressure oil in the reduction chamber 4 to the tank is controlled by the first and second servo valves.
Speed adjustment and parallel adjustment by squeezing with 9,10, speed adjustment by squeezing the flow rate and pressure of pressure oil supplied into the reduction chamber 4 with the first and second servo valves 9,10 when the ram rises, Although parallel adjustment is made, the pressure oil in the second expansion chamber 3 flows out to the tank from the solenoid valve 6, so the pressure supplied to the reduction chamber 4 of the hydraulic cylinder 1 and the outflow are the same at the start of the ram rise. However, the reduction speed of the left and right hydraulic cylinders 1 may differ due to the difference in sliding resistance between the left and right hydraulic cylinders 1 and the ram may rise while fluctuating left and right, which may wear the guide portion of the ram and the like. This is not preferable.

そこで、本考案は前述の課題を解決できるようにした
プレスブレーキの油圧回路を提供することを目的とす
る。
Therefore, an object of the present invention is to provide a hydraulic circuit for a press brake which can solve the above-mentioned problems.

〔課題を解決するための手段及び作用〕[Means and Actions for Solving the Problems]

本考案の油圧回路は、左右一対の油圧リシンダ1によ
りラムを上下動して上型と下型で板材を折曲するプレス
ブレーキにおいて、前記左右一対の油圧シリンダ1を、
第1伸長室2と第2伸長室3と縮少室4を有するものと
し、その左右一対の油圧シリンダ1の第2伸長室3と縮
少室4の一方、又は他方にポンプ5の吐出圧油を供給
し、かつ他方又は一方をタンク12に連通する伸長位置B
と縮少位置Aに切換えられるサーボバルブを設け、前記
第1伸長室2とタンク12を絞りを介して連通する遮断位
置Dと、その第1伸長室2を第2伸長室3に連通する連
通位置Cに切換えられる電磁弁24を設け、前記ラムを上
昇および高速下降する時には電磁弁24を遮断位置Dと
し、ラムを遅速下降する時には電磁弁24を連通位置Cと
するようにしたものであり、これによってラムを高速下
降、遅速下降できるし、ラムを上昇する時に油圧シリン
ダ1の第2伸長室3からタンクへの戻り油の流量を制御
できるようになり、左右油圧シリンダ1の摺動抵抗差等
があってもラムを平行として上昇できる。
The hydraulic circuit of the present invention is a press brake in which a ram is moved up and down by a pair of left and right hydraulic recliners 1 to bend a plate material between an upper die and a lower die, and the pair of left and right hydraulic cylinders 1 are
The first extension chamber 2, the second extension chamber 3, and the reduction chamber 4 are provided, and the discharge pressure of the pump 5 is applied to one or the other of the second extension chamber 3 and the reduction chamber 4 of the pair of hydraulic cylinders 1 on the left and right. Extension position B for supplying oil and communicating the other or one with tank 12
And a shut-off position D for connecting the first expansion chamber 2 and the tank 12 via a throttle, and a communication for connecting the first expansion chamber 2 to the second expansion chamber 3. A solenoid valve 24 that can be switched to the position C is provided so that the solenoid valve 24 is set to the shutoff position D when the ram is raised and lowered at high speed, and the communication valve C is set to the communication position C when the ram is lowered slowly. Thus, the ram can be lowered at a high speed or a slow speed, and when the ram is raised, the flow rate of the return oil from the second extension chamber 3 of the hydraulic cylinder 1 to the tank can be controlled, and the sliding resistance of the left and right hydraulic cylinders 1 can be controlled. The ram can be raised in parallel even if there is a difference.

〔実施例〕〔Example〕

以下本考案の実施例を示す第1図に基づいて説明す
る。なお、従来と同一部材は符号を同一とする。
An embodiment of the present invention will be described below with reference to FIG. It should be noted that the same members as those in the related art have the same reference numerals.

ポンプ5の吐出圧油を第1・第2サーボバルブ9,10の
入口9a,10aに供給する回路20にチェックバルブ21を設
け、第1・第2サーボバルブ9,10の第1ポート9b,10bを
油圧シリンダ1の縮少室4に接続し、第2ポート9c,10c
を第1回路22で第2伸長室3に接続し、第1伸長室2に
接続した第2回路23を電磁弁24で前記第1回路22とタン
ク12の一方に接続する。
A check valve 21 is provided in the circuit 20 which supplies the discharge pressure oil of the pump 5 to the inlets 9a, 10a of the first and second servo valves 9, 10, and the first port 9b, of the first and second servo valves 9, 10 is provided. 10b is connected to the reduction chamber 4 of the hydraulic cylinder 1, and the second ports 9c and 10c are connected.
Is connected to the second expansion chamber 3 by the first circuit 22, and the second circuit 23 connected to the first expansion chamber 2 is connected to the first circuit 22 and one of the tanks 12 by the solenoid valve 24.

次に作動を説明する。 Next, the operation will be described.

ラム上昇時には電磁弁24を遮断位置Dとし、モータ11
で第1・第2サーボバルブ9,10を縮少位置Aとしてポン
プ5の吐出圧油をチェックバルブ21を経て縮少室4に供
給し、その圧力と流量は第1・第2サーボバルブ9,10の
切換えストロークによる絞りによって調整される。また
第1伸長室2内の圧油は第2回路23、電磁弁24の遮断位
置Dの絞りを経てタンク12に流れ、第2伸長室3内の圧
油は第1・第2サーボバルブ9,10の絞りによってタンク
12への流量が調整されるから、油圧シリンダ1に流入、
流出する圧油の流量を第1・第2サーボバルブ9,10の切
換えストロークによる絞りによって制御されるため安定
して左右の油圧シリンダ1の縮少速度を同一としてラム
を平行に上昇できる。
When the ram is raised, the solenoid valve 24 is set to the shutoff position D, and the motor 11
Then, the first and second servo valves 9 and 10 are set to the reduction position A, and the discharge pressure oil of the pump 5 is supplied to the reduction chamber 4 through the check valve 21, and the pressure and flow rate are set to the first and second servo valves 9 and 10. It is adjusted by the diaphragm with 10 and 10 switching strokes. Further, the pressure oil in the first extension chamber 2 flows into the tank 12 via the second circuit 23 and the restriction of the shutoff position D of the solenoid valve 24, and the pressure oil in the second extension chamber 3 is transferred to the first and second servo valves 9 and 9. Tank with 10 apertures
Since the flow rate to 12 is adjusted, it flows into the hydraulic cylinder 1,
Since the flow rate of the pressure oil flowing out is controlled by the throttle by the switching stroke of the first and second servo valves 9 and 10, it is possible to stably raise the rams in parallel while the left and right hydraulic cylinders 1 have the same reduction speed.

ラム高速下降時にはモータ11で第1・第2サーボバル
ブ9,10を伸長位置Bとすると共に、電磁弁24を図示の遮
断位置Dとして、ポンプ5の吐出圧油を第1・第2サー
ボバルブ9,10を経て容量の小さな第2伸長室3に供給
し、縮少室4内の圧油も第1・第2サーボバルブ9,10を
通ってタンク12に流出するので前途と同様に油圧シリン
ダ1に流入、流出する圧油の流量を第1・第2サーボバ
ルブ9,10の絞りにして制御することにより安定な系とな
る。なお容量の大きな第1伸長室2内へはフィリングバ
ルブ13よりタンク内の圧油を吸込む。
When the ram is descending at high speed, the motor 11 sets the first and second servo valves 9 and 10 to the extended position B, and the solenoid valve 24 is set to the shut-off position D shown in the drawing to discharge the pressure oil from the pump 5 to the first and second servo valves. It is supplied to the second expansion chamber 3 with a small capacity via 9 and 10, and the pressure oil in the reduction chamber 4 also flows out to the tank 12 through the first and second servo valves 9 and 10, so the hydraulic pressure is the same as before. A stable system is achieved by controlling the flow rate of the pressure oil flowing in and out of the cylinder 1 by restricting the first and second servo valves 9 and 10. The pressure oil in the tank is sucked into the first expansion chamber 2 having a large capacity from the filling valve 13.

ラム遅速下降時は電磁弁24を連通位置Cに切換え、ポ
ンプ5の吐出圧油を第1・第2サーボバルブ9,10を経て
第1・第2伸長室2,3に供給し、縮少室4内の圧油も第
1・第2サーボバルブ9,10を経てタンク12に流出するか
ら、前記ラム高速下降時と同様に油圧シリンダ1に流入
・流出する圧油の流量を第1・第2サーボバルブ9,10の
絞りで制御する。
When the ram slows down, the solenoid valve 24 is switched to the communication position C, and the pressure oil discharged from the pump 5 is supplied to the first and second extension chambers 2 and 3 via the first and second servo valves 9 and 10 to reduce the pressure. Since the pressure oil in the chamber 4 also flows out to the tank 12 through the first and second servo valves 9 and 10, the flow rate of the pressure oil flowing into and out of the hydraulic cylinder 1 is the same as that at the time of the high speed descent of the ram. It is controlled by the throttle of the second servo valves 9 and 10.

〔考案の効果〕[Effect of device]

左右一対の油圧シリンダ1の第2伸長室3にポンプ5
の吐出圧油をサーボバルブを経て供給し、その縮少室4
内の圧油をサーボバルブを経てタンクに流出することで
ラムを高速下降でき、左右一対の油圧シリンダ1の第
1、第2伸長室2,3にポンプ5の吐出圧油をサーボバル
ブを経て供給し、その縮少室4内の圧油をサーボバルブ
を経てタンクに流出することでラムを遅速下降できる。
A pump 5 is installed in the second extension chamber 3 of the pair of left and right hydraulic cylinders 1.
The discharge pressure oil of is supplied through the servo valve, and the reduction chamber 4
The ram can be lowered at a high speed by letting out the pressure oil in the tank to the tank via the servo valve, and the pressure oil discharged from the pump 5 to the first and second extension chambers 2 and 3 of the pair of left and right hydraulic cylinders 1 via the servo valve. The ram can be moved down slowly by supplying the pressure oil in the reduction chamber 4 to the tank via the servo valve.

したがって、ラムを高速下降、低速下降できるし、そ
の時に油圧シリンダ1に流入、流出する圧油の流量をサ
ーボバルブの絞りにより制御して左右油圧シリンダ1の
摺動抵抗差等があってもラムを平行に下降できる。
Therefore, the ram can descend at a high speed and a low speed, and at that time, even if there is a difference in sliding resistance between the left and right hydraulic cylinders 1 by controlling the flow rate of the pressure oil flowing in and out of the hydraulic cylinder 1 by the throttle of the servo valve. Can descend in parallel.

また、左右一対の油圧シリンダ1の縮少室4にポンプ
5の吐出圧油をサーボバルブを経て供給し、その第1伸
長室2内の圧油を電磁弁24の遮断位置Dの絞りを経てタ
ンクに流出し、第2伸長室3内の圧油をサーボバルブを
経てタンクに流出することでラムを上昇できるし、その
時に油圧シンダ1から流出、流入する圧油の流量をサー
ボバルブの絞りで制御して左右油圧シリンダ1の摺動抵
抗差等があつてもラムを平行に上昇できる。
Further, the discharge pressure oil of the pump 5 is supplied to the reduction chambers 4 of the pair of left and right hydraulic cylinders 1 via the servo valve, and the pressure oil in the first extension chamber 2 is passed through the cutoff position D of the solenoid valve 24. The ram can be raised by flowing out the pressure oil in the second extension chamber 3 into the tank through the servo valve, and at that time, the flow rate of the pressure oil flowing in and out of the hydraulic cylinder 1 is reduced by the servo valve. The ram can be raised in parallel even if there is a difference in sliding resistance between the left and right hydraulic cylinders 1 by controlling.

【図面の簡単な説明】[Brief description of drawings]

第1図は本考案の実施例を示す油圧回路図、第2図は従
来の油圧回路図である。 1は油圧シリンダ、2は第1伸長室、3は第2伸長室、
4は縮少室、5はポンプ、9,10は第1・第2サーボバル
ブ、24は電磁弁。
FIG. 1 is a hydraulic circuit diagram showing an embodiment of the present invention, and FIG. 2 is a conventional hydraulic circuit diagram. 1 is a hydraulic cylinder, 2 is a first extension chamber, 3 is a second extension chamber,
4 is a reduction chamber, 5 is a pump, 9 and 10 are first and second servo valves, and 24 is a solenoid valve.

Claims (1)

【実用新案登録請求の範囲】[Scope of utility model registration request] 【請求項1】左右一対の油圧シリンダ1によりラムを上
下動して上型と下型で板材を折曲するプレスブレーキに
おいて、前記左右一対の油圧シリンダ1を、第1伸長室
2と第2伸長室3と縮少室4を有するものとし、その左
右一対の油圧シリンダ1の第2伸長室3と縮少室4の一
方、又は他方にポンプ5の吐出圧油を供給し、かつ他方
又は一方をタンク12に連通する伸長位置B又は縮少位置
Aに切換えられるサーボバルブを設け、前記第1伸長室
2とタンク12を絞りを介して連通する遮断位置Dと、そ
の第1伸長室2を第2伸長室3に連通する連通位置Cに
切換えられる電磁弁24を設け、前記ラムを上昇および高
速下降する時には電磁弁24を遮断位置Dとし、ラムを遅
速下降する時には電磁弁24を連通位置Cとするようにし
たプレスブレーキの油圧回路。
1. A press brake in which a ram is moved up and down by a pair of left and right hydraulic cylinders 1 to bend a plate material between an upper die and a lower die, wherein the pair of left and right hydraulic cylinders 1 are connected to a first extension chamber 2 and a second extension chamber 2. An extension chamber 3 and a reduction chamber 4 are provided, and the discharge pressure oil of the pump 5 is supplied to one or the other of the second extension chamber 3 and the reduction chamber 4 of the pair of left and right hydraulic cylinders 1 and the other or A servo valve for switching one to the extended position B or the reduced position A, which communicates with the tank 12, is provided, and the shut-off position D for communicating the first expansion chamber 2 with the tank 12 via a throttle and the first expansion chamber 2 therefor. Is provided with a solenoid valve 24 that is switched to a communication position C that communicates with the second extension chamber 3. When the ram is raised and lowered at a high speed, the solenoid valve 24 is set to a shutoff position D, and when the ram is lowered slowly, the solenoid valve 24 is connected. Oil for the press brake that is set to position C Pressure circuit.
JP1990030950U 1990-03-28 1990-03-28 Press brake hydraulic circuit Expired - Lifetime JPH087934Y2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1990030950U JPH087934Y2 (en) 1990-03-28 1990-03-28 Press brake hydraulic circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1990030950U JPH087934Y2 (en) 1990-03-28 1990-03-28 Press brake hydraulic circuit

Publications (2)

Publication Number Publication Date
JPH03126221U JPH03126221U (en) 1991-12-19
JPH087934Y2 true JPH087934Y2 (en) 1996-03-06

Family

ID=31533673

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1990030950U Expired - Lifetime JPH087934Y2 (en) 1990-03-28 1990-03-28 Press brake hydraulic circuit

Country Status (1)

Country Link
JP (1) JPH087934Y2 (en)

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0824963B2 (en) * 1985-09-06 1996-03-13 株式会社アマダ Ram drive controller for folding machine
AT385466B (en) * 1985-12-30 1988-04-11 Hoerbiger Hydraulik SIMULTANEOUS CONTROL UNIT FOR A HYDRAULIC MULTI-CYLINDER DRIVE
JPH0353834Y2 (en) * 1986-08-15 1991-11-26

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Publication number Publication date
JPH03126221U (en) 1991-12-19

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