JPH08108204A - Hydraulic screw-down device for rolling mill and method thereof - Google Patents
Hydraulic screw-down device for rolling mill and method thereofInfo
- Publication number
- JPH08108204A JPH08108204A JP24148494A JP24148494A JPH08108204A JP H08108204 A JPH08108204 A JP H08108204A JP 24148494 A JP24148494 A JP 24148494A JP 24148494 A JP24148494 A JP 24148494A JP H08108204 A JPH08108204 A JP H08108204A
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- Prior art keywords
- cylinder
- pressure
- hydraulic
- ram
- cylinder ram
- 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.)
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、圧延機の油圧圧下装置
及びその方法の改良に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvements in a hydraulic pressure reduction device and method for a rolling mill.
【０００２】[0002]
【従来の技術】従来の圧延機の油圧圧下装置は、図７に
示すように位置制御盤、油圧サーボバルブ、油圧シリン
ダ、油圧シリンダラム位置検出器からなっている。位置
指令値が位置制御盤に与えられると、位置指令値と油圧
シリンダラム位置の偏差が零となるように油圧サーボバ
ルブが電気的に駆動される。ここで、油圧シリンダラム
の位置制御には、図８に示すようにデッドタイムと制御
遅れの２つの時間遅れが存在する。この、遅れが特に問
題となるのは、荷重（圧延反力変動）が急激に変化する
材料の噛込み時で、材料の噛込みとともに、油圧シリン
ダラムは沈み込み、位置指令値とのラム位置の偏差によ
り、油圧サーボバルブはラムの位置を修正するように作
動油を油圧シリンダに供給しようとするが、上記制御遅
れのため、サーボバルブからの圧油の供給は間に合わ
ず、油圧シリンダは外力に釣り合う負荷圧力が立つまで
その位置が沈む。そこで、現在、圧延荷重の推定によ
り、沈み込み量を予測し、位置指令値に予めその量
“ａ”を上乗せし、材料の噛込み検出後、その補正量を
零へ暫減させる油圧シリンダ沈み込み補正制御（図９）
を行っているが、材料のトラッキングが難しく、制御精
度はあまり高くない。2. Description of the Related Art A conventional hydraulic pressure reduction device for a rolling mill comprises a position control board, a hydraulic servo valve, a hydraulic cylinder, and a hydraulic cylinder ram position detector as shown in FIG. When the position command value is given to the position control panel, the hydraulic servo valve is electrically driven so that the deviation between the position command value and the hydraulic cylinder ram position becomes zero. Here, in the position control of the hydraulic cylinder ram, there are two time delays, a dead time and a control delay, as shown in FIG. This delay is especially problematic when the load (rolling reaction force variation) changes suddenly when the material is jammed, as the material is jammed, the hydraulic cylinder ram sinks and the ram position relative to the position command value. Deviation causes the hydraulic servo valve to try to supply hydraulic oil to the hydraulic cylinder so as to correct the ram position, but due to the above control delay, the hydraulic oil cannot be supplied from the servo valve in time and the hydraulic cylinder is forced to operate by an external force. The position sinks until there is a load pressure that balances with. Therefore, at present, by predicting the rolling load, the amount of subsidence is predicted, the amount "a" is added to the position command value in advance, and the amount of correction is temporarily reduced to zero after the detection of material jamming. Inclusion correction control (Fig. 9)
However, it is difficult to track the material and the control accuracy is not so high.
【０００３】[0003]
【発明が解決しようとする課題】このように従来技術で
は、油圧圧下シリンダの沈み込み制御を、タイミング合
わせの難しい位置指令補正方法によっていたため、制御
精度もあまり高くなかった。そこで、本発明は、新しい
圧力供給機構とからなる油圧圧下シリンダにより、従来
技術のような複雑な制御が不要で、かつ制御性が良く、
容易に精度の高い製品の圧延を可能にしようとするもの
である。As described above, in the prior art, since the depression control of the hydraulic pressure reduction cylinder is performed by the position command correction method in which the timing adjustment is difficult, the control accuracy is not so high. Therefore, the present invention uses a hydraulic pressure reduction cylinder including a new pressure supply mechanism, does not require complicated control as in the conventional technique, and has good controllability.
It is intended to enable easy and accurate rolling of products.
【０００４】[0004]
【課題を解決するための手段】かかる問題点を解決する
ため、本発明は、シリンダラム操作用の方向制御弁を該
シリンダラムに一体的に組込み、前記方向制御弁スプー
ルの一端をスプール位置制御装置と連結し、スプールの
位置にラムが追従するように油圧機構を形成した圧延機
の油圧圧下装置において、シリンダラム駆動用油圧装置
とシリンダ反負荷側の圧力上昇用油圧装置を設けること
により、負荷側排圧圧力を高く設定せしめる如く構成し
たことを特徴とする。In order to solve the above problems, the present invention integrally incorporates a directional control valve for operating a cylinder ram into the cylinder ram, and controls one end of the directional control valve spool to spool position control. In the hydraulic pressure reducing device of the rolling mill, which is connected to the device and has a hydraulic mechanism so that the ram follows the position of the spool, by providing a cylinder ram driving hydraulic device and a cylinder pressure increasing hydraulic device on the cylinder anti-load side, It is characterized in that the load side exhaust pressure is set to be high.
【０００５】また、その方法として、圧延材の噛込み前
に、油圧シリンダ内の反負荷側の油圧圧力を高くするこ
とにより同油圧シリンダ内の負荷側の油圧圧力をあらか
じめ高くし、材料の噛込みと同時に起こるシリンダラム
沈み込みにより、前記同上方向制御弁スプール部にでき
る開孔部から油圧シリンダ負荷側への圧油の供給、油圧
シリンダ反負荷側からの圧油の排出を行うことで、圧延
反力に抗するに必要な負荷側油圧の圧力上昇時間を最短
とし、シリンダラムの沈み込み量を最小にすることを特
徴とする圧延機の油圧圧下方法を提供するものである。Further, as a method thereof, before the biting of the rolled material, the hydraulic pressure on the anti-load side in the hydraulic cylinder is increased to increase the hydraulic pressure on the load side in the hydraulic cylinder in advance, and the material is caught. By the cylinder ram sinking that occurs at the same time as the above, by supplying pressure oil to the hydraulic cylinder load side from the opening formed in the above-mentioned directional control valve spool part, and discharging pressure oil from the hydraulic cylinder anti-load side, (EN) A hydraulic rolling reduction method for a rolling mill characterized by minimizing the pressure rise time of the load side hydraulic pressure required to resist the rolling reaction force and minimizing the amount of depression of the cylinder ram.
【０００６】[0006]
【作用】前述の手段により、圧延材料の噛込みによる圧
延反力の急激な負荷による油圧シリンダラムの沈み込み
と同時に、即座に油圧シリンダラム負荷側に圧力油が供
給され、一方、油圧シリンダ反負荷側からの圧油の排出
が行われ、また、油圧シリンダラム負荷側圧力は事前
に、油圧シリンダラムの反負荷側の圧力の上昇により昇
圧されているので、圧延反力による油圧圧下シリンダラ
ムの沈み込みに対して抗力があり、油圧シリンダラムの
沈み込みを最小にすることができる。With the above-mentioned means, pressure oil is immediately supplied to the load side of the hydraulic cylinder ram at the same time as the hydraulic cylinder ram sinks due to the sudden load of the rolling reaction force due to the biting of the rolled material, while Since the pressure oil is discharged from the load side and the pressure on the hydraulic cylinder ram load side has been raised in advance by the increase in pressure on the anti-load side of the hydraulic cylinder ram, the hydraulic pressure reduction cylinder ram due to the rolling reaction force There is a resistance to the subduction of the hydraulic cylinder ram, and the subduction of the hydraulic cylinder ram can be minimized.
【０００７】この際、油圧シリンダラム反負荷側圧力を
高く調整することによる圧延反力に対する出力低下は、
シリンダラムの沈み込み発生と同時に、油圧シリンダラ
ム反負荷側圧力をタンクＴへ解放するため、問題とはな
らない。At this time, the output reduction with respect to the rolling reaction force due to the high adjustment of the pressure on the anti-load side of the hydraulic cylinder ram is
At the same time when the cylinder ram sinks, the hydraulic cylinder ram anti-load side pressure is released to the tank T, so there is no problem.
【０００８】[0008]
【実施例】以下、本発明を、その実施例（図１）に基づ
いて詳細に説明する。図２は、水平ミルの圧上装置に本
発明を適用した場合を示す。下水平ロールチョックアッ
センブリを鉛直方向に支持する油圧圧下シリンダ１は、
上下面がシリンダチューブ２外面に解放されたシリンダ
ラム３を内蔵している。このシリンダラム３には、下端
部から軸方向に中空円筒状のスリーブ４を嵌着してい
る。このスリーブ４内にはスプール５が摺動可能に挿入
され、スプール５は所要ピッチにてスリーブ４内周面を
摺動するランド６が設けられ、スリーブ内周壁とともに
第１、第２、第３弁室７、８、９を画成する。The present invention will be described in detail below based on its embodiment (FIG. 1). FIG. 2 shows a case where the present invention is applied to the uplifting device of a horizontal mill. The hydraulic pressure reduction cylinder 1 that vertically supports the lower horizontal roll chock assembly is
The cylinder ram 3 whose upper and lower surfaces are open to the outer surface of the cylinder tube 2 is built in. A hollow cylindrical sleeve 4 is axially fitted to the cylinder ram 3 from the lower end. A spool 5 is slidably inserted into the sleeve 4, and a land 6 that slides on the inner peripheral surface of the sleeve 4 at a required pitch is provided in the spool 5, and together with the inner peripheral wall of the sleeve, first, second, and third sleeves are provided. The valve chambers 7, 8 and 9 are defined.
【０００９】さらに、スリーブ４には、３弁室と同時に
整合可能なピッチで入口ポート１０、及び第１、第２出
口ポート１１、１２を穿設し、入口ポート１０はシリン
ダラム３に形成される流路Ｆ1 を経て油圧ポンプＰに連
通し、第１、第２出口ポート１１、１２は同様に流路Ｆ
2 を経て油タンクＴに連通している。また、１３はシリ
ンダチューブ２のシリンダラム３下位側に連通する第１
ポート、１４はシリンダラム３上位側に連通する第２ポ
ートで、両者はシリンダラム３内に形成される流路
Ｆ3 、Ｆ4 によりシリンダチューブ２内と連通する。Further, the sleeve 4 is provided with the inlet port 10 and the first and second outlet ports 11 and 12 at a pitch that allows simultaneous alignment with the three valve chambers, and the inlet port 10 is formed in the cylinder ram 3. Communicating with the hydraulic pump P via the flow passage F 1 and the first and second outlet ports 11 and 12 are also the flow passage F 1.
It communicates with the oil tank T via 2 . In addition, 13 is a first communicating with the lower side of the cylinder ram 3 of the cylinder tube 2.
Ports 14 are second ports communicating with the upper side of the cylinder ram 3, both of which communicate with the inside of the cylinder tube 2 by the flow paths F 3 and F 4 formed in the cylinder ram 3.
【００１０】１５はシリンダラム反負荷側１８の圧力上
昇用の油圧装置で、バルブ１７の“開”動作にて、シリ
ンダラム反負荷側の油圧を上昇させる。この油圧上昇の
手段としては、例えばシステム圧力より高圧の別油圧源
を設けるか、図３に示すブーストシリンダ１６による方
法などがある。このシリンダラム反負荷側１８の油圧圧
力の上昇ΔＰR により、シリンダラム負荷側１９の圧力
はΔＰH 上昇する。Reference numeral 15 denotes a hydraulic device for increasing the pressure on the side opposite to the cylinder ram 18, which raises the oil pressure on the side opposite to the cylinder ram by the opening operation of the valve 17. As means for increasing the hydraulic pressure, for example, another hydraulic pressure source having a pressure higher than the system pressure is provided, or the boost cylinder 16 shown in FIG. 3 is used. Due to the increase ΔP R of the hydraulic pressure on the cylinder ram anti-load side 18, the pressure on the cylinder ram load side 19 increases ΔP H.
【００１１】ここで、材料の噛込みによる圧延反力の急
激な増大により、油圧シリンダラム３が“δ”沈み込ん
だ場合のシリンダラムの位置挙動について述べる。ま
ず、シリンダラム３の負荷圧力が圧延荷重に釣り合う圧
力に達するまでシリンダラム３が下降する。ここで、ス
プール５の位置は変わらないので、図４に示すように、
入口ポート１０と第１ポート１３が第２弁室８を介して
連通するとともに、第２ポート１４と第１出口ポート１
１が第３弁室９を介して連通する。したがって、油圧ポ
ンプＰからシリンダチューブ２内のシリンダラム負荷側
１９に圧油が供給され、かつシリンダラム反負荷側１８
からは、タンクＴへ油が排出され、シリンダラム３は上
昇し、元の位置へ復帰しようとする。この場合、従来方
式に比べシリンダラム３の負荷側圧力を高く設定できる
ため、シリンダラム３の下降量は、小さくできるのと、
僅かの下降量でも、即座にシリンダラム３と組込みのス
プール４間に変位が生じ、圧油をシリンダラム３の負荷
側１９へ供給できるため、その下降量は従来に比べ大幅
に抑制できる。Here, the position behavior of the hydraulic cylinder ram 3 when the hydraulic cylinder ram 3 sinks "δ" due to the rapid increase of the rolling reaction force due to the biting of the material will be described. First, the cylinder ram 3 descends until the load pressure of the cylinder ram 3 reaches a pressure balanced with the rolling load. Here, since the position of the spool 5 does not change, as shown in FIG.
The inlet port 10 and the first port 13 communicate with each other via the second valve chamber 8, and the second port 14 and the first outlet port 1
1 communicates with each other through the third valve chamber 9. Therefore, pressure oil is supplied from the hydraulic pump P to the cylinder ram load side 19 in the cylinder tube 2, and the cylinder ram counter load side 18 is supplied.
Then, the oil is discharged to the tank T, the cylinder ram 3 rises, and tries to return to the original position. In this case, since the load side pressure of the cylinder ram 3 can be set higher than that of the conventional method, the descending amount of the cylinder ram 3 can be reduced.
Even with a small amount of descending, displacement immediately occurs between the cylinder ram 3 and the built-in spool 4, and the pressure oil can be supplied to the load side 19 of the cylinder ram 3, so that the amount of descending can be suppressed significantly compared to the conventional case.
【００１２】本発明において、シリンダラムの位置制御
はシリンダラムに組込みのスプールの位置制御のみで、
シリンダラムをこれに倣わせても良いし（図５）、シリ
ンダラムに取り付けた位置検出器により、スプールの位
置を動かし、シリンダラムが目標位置に来るようにその
位置を制御しても良い（図６）。In the present invention, the position control of the cylinder ram is only the position control of the spool incorporated in the cylinder ram,
The cylinder ram may be made to follow this (FIG. 5), or the position detector attached to the cylinder ram may move the position of the spool to control the position so that the cylinder ram reaches the target position ( (Figure 6).
【００１３】尚、上述した本装置は、圧延機の水平圧下
・圧上装置および竪圧下装置のいずれにも適用可能であ
る。The above-described present apparatus can be applied to any of the horizontal rolling / rolling up apparatus and vertical rolling apparatus of a rolling mill.
【００１４】[0014]
【発明の効果】本発明により、従来の圧延機の油圧圧下
装置において、製品精度上問題となっていた、圧延材料
の噛込みによる油圧シリンダラムの沈み込みによる板厚
の増大を、圧延荷重の推定により沈み込み量を予測し、
位置指令値に予めその量を上乗せし、トラッキングによ
る材料の噛込み位置検出に合わせてその補正量を零へ暫
減させるという、複雑な油圧シリンダの沈み込み補償制
御を行うことなしに、容易に精度よく実現できる。EFFECTS OF THE INVENTION According to the present invention, in the conventional hydraulic pressure reduction device for a rolling mill, the increase of the plate thickness due to the sinking of the hydraulic cylinder ram due to the biting of the rolling material, which has been a problem in terms of product accuracy, is reduced. Predict the subduction amount by estimation,
It is easy to add the amount to the position command value in advance, and temporarily reduce the correction amount to zero in accordance with the detection of the biting position of the material by tracking, without performing complicated depression control of the hydraulic cylinder. Can be realized with high accuracy.
【図１】本発明の実施例を示す断面図。FIG. 1 is a sectional view showing an embodiment of the present invention.
【図２】本発明を水平ミルの圧上装置に適用した場合。FIG. 2 shows a case where the present invention is applied to a horizontal mill uplifting device.
【図３】本発明の別の実施例を示す図面。FIG. 3 is a view showing another embodiment of the present invention.
【図４】本発明の実施例を示す断面図。FIG. 4 is a sectional view showing an embodiment of the present invention.
【図５】本発明の別の実施例を示す図面。FIG. 5 is a view showing another embodiment of the present invention.
【図６】本発明の別の実施例を示す図面。FIG. 6 is a view showing another embodiment of the present invention.
【図７】従来の圧延機の油圧圧下装置。FIG. 7 is a hydraulic reduction device for a conventional rolling mill.
【図８】従来の圧延機の油圧圧下時のシリンダラムの位
置制御。[Fig. 8] Position control of a cylinder ram during hydraulic reduction of a conventional rolling mill.
【図９】従来の圧延機の油圧シリンダの沈み込み補正制
御方法。FIG. 9 is a conventional sinking correction control method for a hydraulic cylinder of a rolling mill.
１ 油圧圧下シリンダ ２ シリンダチューブ ３ シリンダラム ４ スリーブ ５ スプール ６ ランド ７ 第１弁室 ８ 第２弁室 ９ 第３弁室 １０ 入口ポート １１ 第１出口ポート １２ 第２出口ポート １３ 第１ポート １４ 第２ポート １５ シリンダラム反負荷側の圧力上昇用の油圧装置 １６ シリンダラム駆動用の油圧装置 １７ バルブ １８ シリンダラム反負荷側 １９ シリンダラム負荷側 1 Hydraulic Reduction Cylinder 2 Cylinder Tube 3 Cylinder Ram 4 Sleeve 5 Spool 6 Land 7 1st Valve Chamber 8 2nd Valve Chamber 9 3rd Valve Chamber 10 Inlet Port 11 1st Outlet Port 12 2nd Outlet Port 13 1st Port 14 14th 2-port 15 Hydraulic device for increasing pressure on the opposite side of the cylinder ram 16 Hydraulic device for driving cylinder ram 17 Valve 18 Cylinder ram opposite load side 19 Cylinder ram load side
Claims (2)
リンダラムに一体的に組込み、前記方向制御弁スプール
の一端をスプール位置制御装置と連結し、スプールの位
置にラムが追従するように油圧機構を形成した圧延機の
油圧圧下装置において、シリンダラム駆動用油圧装置と
シリンダ反負荷側の圧力上昇用油圧装置を設けることに
より、負荷側圧力を高く設定せしめる如く構成したこと
を特徴とする圧延機の油圧圧下装置。1. A directional control valve for operating a cylinder ram is integrally incorporated in the cylinder ram, one end of the directional control valve spool is connected to a spool position control device, and a hydraulic pressure is set so that the ram follows the position of the spool. In the hydraulic pressure reducing device of the rolling machine having the mechanism, the rolling device is configured so that the load side pressure can be set high by providing a cylinder ram drive hydraulic device and a cylinder anti load side pressure increasing hydraulic device. Machine hydraulic reduction device.
リンダラムに一体的に組込み、前記方向制御弁スプール
の一端をスプール位置制御装置と連結し、スプールの位
置にラムが追従するように油圧機構を形成した圧延機の
油圧圧下方法において、圧延材の噛込み前に、油圧シリ
ンダ内の反負荷側の油圧圧力を高くすることにより同油
圧シリンダ内の負荷側の油圧圧力をあらかじめ高くし、
材料の噛込みと同時に起こるシリンダラム沈み込みによ
り、前記同上方向制御弁スプール部にできる開孔部から
油圧シリンダ負荷側への圧油の供給、油圧シリンダ反負
荷側からの圧油の排出を行うことで、圧延反力に抗する
に必要な負荷側油圧の圧力上昇時間を最短とし、シリン
ダラムの沈み込み量を最小にすることを特徴とする圧延
機の油圧圧下方法。2. A directional control valve for operating a cylinder ram is integrally incorporated in the cylinder ram, one end of the directional control valve spool is connected to a spool position control device, and a hydraulic pressure is set so that the ram follows the position of the spool. In the rolling reduction method of a rolling mill having a mechanism, before the rolling material is bitten, the hydraulic pressure on the anti-load side in the hydraulic cylinder is increased to increase the hydraulic pressure on the load side in the hydraulic cylinder in advance.
Due to the cylinder ram sinking that occurs at the same time as the material is bitten, pressure oil is supplied to the hydraulic cylinder load side from the opening formed in the directional control valve spool, and pressure oil is discharged from the hydraulic cylinder counter load side. Therefore, the pressure rise time of the load side hydraulic pressure required to resist the rolling reaction force is minimized, and the amount of depression of the cylinder ram is minimized.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24148494A JPH08108204A (en) | 1994-10-05 | 1994-10-05 | Hydraulic screw-down device for rolling mill and method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24148494A JPH08108204A (en) | 1994-10-05 | 1994-10-05 | Hydraulic screw-down device for rolling mill and method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH08108204A true JPH08108204A (en) | 1996-04-30 |
Family
ID=17075007
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP24148494A Withdrawn JPH08108204A (en) | 1994-10-05 | 1994-10-05 | Hydraulic screw-down device for rolling mill and method thereof |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH08108204A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102013224644A1 (en) | 2013-11-29 | 2015-06-03 | Sms Siemag Aktiengesellschaft | Device for adjusting a roll in a roll stand |
-
1994
- 1994-10-05 JP JP24148494A patent/JPH08108204A/en not_active Withdrawn
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102013224644A1 (en) | 2013-11-29 | 2015-06-03 | Sms Siemag Aktiengesellschaft | Device for adjusting a roll in a roll stand |
| WO2015078822A1 (en) | 2013-11-29 | 2015-06-04 | Sms Siemag Ag | Device for adjusting a roll in a roll stand |
| US10124380B2 (en) | 2013-11-29 | 2018-11-13 | Sms Group Gmbh | Device for adjusting a roll in a roll stand |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 20020115 |