JPH06170637A - Steel plate transport method in steel plate shearing facility - Google Patents

Abstract

PURPOSE:To provide a means to prevent meander of steel plates and eliminate a height difference in a cutting surface when a steel plate is fed intermittently by a pinch roll and cut by a double side shear and a slitter. CONSTITUTION:A clutch 11 is located at an upper roll drive shaft section of a pinch roll 4-1 which feeds a steel plate at a constant pitch intermittently. When a steel plate is transported, the upper roll 4-1 is made in contact idly with the clutch 11, and a lower roll 4-2 only is driven to feed the steel plate at a constant pitch. Accordingly, because the upper roll 4-1 of the pinch roll is not driven, the unbalance of an upper roll drive torque, which is the main cause of meander of steel plates, can be eliminated. Since the steel plate can be fed in straight forward direction at a constant pitch, the cutting accuracy of it can be increased. For heavy objects, the upper roll 4-1 is driven by the clutch 11 to prevent the lower roll 4-2 from being overloaded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates mainly to a method for conveying steel plates in a shearing apparatus for thick steel plates, and more specifically to a double side shear by transferring the steel plates intermittently in the longitudinal direction by a plurality of sets of pinch rolls. The present invention relates to a method for conveying a steel sheet, which prevents the steel sheet from meandering when cutting with a slitter, thereby eliminating the step of the cut surface.

[0002]

2. Description of the Related Art As shown in FIG. 5, the shearing equipment for steel plates such as thick plates has a double side shear 2 for cutting both edges of the steel plate in the longitudinal direction and a central part in the width direction of the steel plate 1 along a steel plate shearing line. The slitter 3 for cutting is arranged adjacently, and the widthwise both ends of the steel plate are sandwiched between the upper and lower sides of the double side shear 2 between the double side shear 2 and the slitter 3 and the slitter 3 exit side. A pair of upper and lower pinch rolls 4a, 4b, 4c are arranged.

The above-mentioned three sets of pinch rolls 4a, 4b, 4c arranged at the three positions of the inlet side, the intermediate side and the outlet side are both motors 6 for both the upper roll 4-1 and the lower roll 4-2.
-1, 6-2 is rotatably driven via speed reducers 7-1, 7-2. One of the pinch rolls located at both ends of the steel plate 1 is fixed and the other is movable. ing. 8-1 and 8-2 are roll axes.

That is, as shown in the side view of FIG. 6, the fixed side of each pinch roll is installed on the fixed base 5-1 installed on the machine base 5, and the movable side is installed on the movable base 5-2. Moreover, the upper roll 4-1 and the lower roll 4-2 have a mechanism that is opened and closed by the fluid pressure cylinder 9.
Further, the lower roll 4-2 is synchronized with the fixed side and the movable side by the connecting shaft 10. The upper roll 4-1 is driven independently, and synchronization with the lower roll 4-1 is performed by electrical control.

When cutting the steel sheet 1, first, the steel sheet 1 is carried into the steel sheet shearing equipment by a table roller (not shown), temporarily stopped at the cutting position of the double side shear 2, and the steel sheet 1 is moved by the entrance side pinch roll 4a. When the steel plate 1 is sandwiched, the double side shear 2 starts cutting, and at the same time as the cutting is completed, the steel plate 1 is fed by the entrance side pinch roll 4a for a certain length. Cutting with this double-side shear 2 and entry-side pinch roll 4
When the tip of the steel sheet passes through the intermediate pinch roll 4b after repeating the constant length feeding by a, the steel sheet is sandwiched by the intermediate pinch roll 4b, and the cutting and the constant length feeding are repeated.
During cutting by the slitter 3, the delivery side pinch roll 4c is also operated to sandwich the steel plate 1. When the rear end of the steel plate 1 passes through the entrance side pinch roll 4a, the entrance side pinch roll 4a
Open to release the steel plate, then the intermediate pinch roll 4b
Repeat feeding for a certain length with.

[0006]

However, in the plate feeding method using the three sets of pinch rolls 4a, 4b, 4c arranged at the three positions of the entrance side, the intermediate side and the exit side in the above-mentioned steel plate cutting equipment, the steel plate is particularly used. Meandering occurs remarkably on the leading end side and the trailing end side of the plate, and a step is formed on the cut surface of the plate. FIG. 7 exemplifies a steel plate having such a step. The top part of the steel plate is meandered when entering, and the bottom part of the steel plate is meandered when slipping out, resulting in steps 1-1 and 1-2, respectively. In addition, since the intermediate portion of the steel sheet is conveyed relatively stably, there is almost no step. The size of the step is usually about 3 to 4 mm.

The causes of the meandering of the steel sheet are (1) the imbalance of the driving torque of each pinch roll, (2) the fixed side,
Unbalanced or insufficient pressure between pinch rolls on the movable side, (3) Difference in pinch roll diameter (peripheral speed difference),
(4) Variations in the coefficient of friction of the steel sheet can be considered, but it is estimated that (1) the imbalance of the driving torque of each pinch roll has a particularly large effect. In particular,
A major cause is the difference in drive torque between the fixed side and the movable side of the upper roll of each pinch roll.

As a countermeasure, for example, there is a method in which a current regulator or a speed regulator is attached to the driving portion of each of the fixed and movable upper rolls to correct the meandering depending on the meandering direction of the steel sheet and the shape of the step. However, this method is difficult to adopt because the friction coefficient changes depending on the dimensions of the steel sheet, the weight of the steel sheet, the surface condition of the steel sheet, etc., and the current and speed must be adjusted each time.

To solve such problems, for example, (a) a method of detecting the slip of the pinch roll to change the pressing force of the steel sheet (see Japanese Patent Publication No. 60-26444), (b) the rear side of the slitter exit side pinch roll. Further, a method of disposing pinch rolls (see Japanese Patent Application Laid-Open No. 54-20479), and (c) two sets of three sets of pinch rolls arranged at three positions on the inlet side, the intermediate side, and the outlet side. A method (see Japanese Utility Model Laid-Open No. 61-92432), (d) a method of mechanically connecting upper and lower rolls of a pinch roll, and the like have been proposed.

However, the method (a) has a problem that the control system is complicated and the equipment cost is high, and the methods (b) and (c) cause the meandering of the steel sheet when the driving torque of the pinch roll becomes unbalanced. , It is not effective as a meandering suppression means,
There is also the problem that equipment costs are high. further,
The method (d) is effective as a meandering suppressing means,
Since this method changes the meandering suppression effect of the steel sheet depending on the roll diameter, it is important to manage the diameter difference between the rolls, and there is a difficulty in practical use.

In order to solve the above-mentioned problems of the prior art, the present invention can effectively suppress the meandering of the steel sheet by a simple means which makes it easy to control the roll diameter of the pinch roll and also requires a low equipment cost. At the same time, the present invention intends to propose a steel plate conveying method that can sufficiently cope with the size of the steel plate, the weight of the steel plate, the surface condition of the steel plate, and the like.

[0012]

According to the present invention, a double side shear and a slitter are arranged adjacent to a steel plate shearing line, and are arranged on the double side shear entry side, between the double side shear and the slitter, and on the slitter exit side. Also, in the equipment for shearing the steel sheet by intermittently conveying the steel sheet in the longitudinal direction with a pair of upper and lower pinch rolls that drive by sandwiching both widthwise end portions of the steel sheet from above and below, in the upper roll drive shaft portion of the pinch roll. A steel sheet conveying method in a steel sheet shearing facility, characterized in that a clutch is provided to make the roll idle, and the upper roll of the pinch roll is brought into idle contact when the steel sheet is conveyed, and only the lower roll is driven to feed the steel sheet at a fixed size. Is the gist.

[0013]

[Function] The pinch rolls arranged on the double side shear entry side, between the double side shears and the slitter, and on the slitter exit side are fixed rolls and movable rolls of the lower rolls connected by a connecting shaft (synchronous shaft) and the upper rolls. Are driven independently.

In the present invention, a method is provided in which a clutch is provided on the upper roll drive shaft of the pinch roll to make the roll idle, and the upper roll of the pinch roll is brought into idling contact when the steel sheet is conveyed. For the reason shown in. As for the meandering of the steel plate, a thin steel plate and a short steel plate tend to be generated depending on the kind of the steel plate. That is, the lighter the weight, the more susceptible it is to the unbalance of the roll torques.
Therefore, as a means for suppressing the meandering of the steel plate, the upper roll, which causes torque imbalance, is brought into idling contact with the upper roll so as to give only the action of sandwiching the steel plate without giving the steel plate conveying torque, and the fixed-size feed of the steel plate is performed only by the lower roll. We have found that it is effective to carry in. However, since the steel plate transport torque is halved in calculation when the upper roll is idled, an overload of the drive motor during transport of heavy goods is expected. In order to avoid this, a clutch for connecting and disconnecting the roll and the drive shaft is provided in the upper roll driving unit, and in the case of a steel plate such as a light steel plate that tends to cause meandering, the upper roll is switched to idle by the clutch and When an overload is expected on the lower roll drive motor, such as during conveyance, the upper and lower drive motors can be used for conveyance.

As described above, according to the present invention, when a steel plate such as a light steel plate which tends to cause meandering is conveyed, the upper roll is brought into idling contact and conveyed only by the lower roll, which is a major cause of the meandering of the steel plate. Since the unbalance of the upper roll driving torque can be eliminated, the steel sheet can be conveyed straight, and the step of the steel sheet cut surface due to the double side shear and the slitter can be prevented.

[0016]

1 is a schematic plan view of a steel plate shearing equipment shown as an embodiment of the method of the present invention, FIG. 2 is a schematic side view of an entrance side pinch roll in the above shearing equipment, and 11 is a clutch.

That is, in the present invention, the upper rolls 4-1 of the pinch rolls 4a, 4b, 4c arranged on the entrance side of the double side shear 2, between the double side shear 2 and the slitter 3, and on the exit side of the slitter 3, respectively. A clutch 11 is provided on the drive shaft portion of the. This clutch is provided between the speed reducer 7-1 and the roll shaft 8-1 so that the upper roll can be switched between driving and non-driving (idling).

When the steel sheet is cut by the above shearing equipment,
The upper roll 4-1 is switched to non-driving by the clutch 11 provided on the drive shaft portion of each upper roll 4-1 to convey the steel sheet. That is, when the steel plate is conveyed, the upper roll 4-1 is brought into idling contact and the steel plate 1 is conveyed only by the lower roll 4-2. Therefore, the upper roll 4-1 merely serves to sandwich the steel plate 1 and the driving torque of the upper roll is reduced. Since the imbalance does not occur, the steel sheet 1 is conveyed straight without meandering. Therefore, the stepping of the cut surface by the double side shear 2 and the slitter 3 is significantly reduced.

Example 1 Upper rolls 4 of pinch rolls 4a, 4b, 4c arranged on the inlet side of the double side shear 2, between the double side shear 2 and the slitter 3, and on the outlet side of the slitter 3.
In order to investigate that the difference in the driving torque of No. 1 influences the meandering of the steel plate during the conveyance of the steel plate, as shown in FIG. 3, the stress measuring instrument 13 is attached to the bracket 12 of the entrance side pinch roll of the double side shear 2 and the bracket is attached to the bracket. The stress acting and the current value of each pinch roll were measured. Prior to measurement, it was expected that tensile stress would be applied during acceleration and compressive stress would be applied during deceleration. The results of this example are shown in FIG.

From the results shown in FIG. 4, it was found that the compressive stress acts even during acceleration, and the bracket compressive stress value also changes due to the change in the current of the drive motor of the upper roll. This indicates that a difference occurs in driving torque between the fixed side and the movable side of the upper roll, which causes the meandering of the steel sheet. That is, from the result of FIG. 4, a large compressive stress acts on the bracket of the fixed-side upper roll during acceleration. At this time, the fixed-side upper roll is in a non-working state, and the steel plate is swung to the fixed side, which causes meandering.

Therefore, when the speed reducer and the drive motor of the upper roll were removed and the steel plate was conveyed only by the lower roll connected by the connecting shaft (synchronous shaft), the meandering of the steel plate was improved. No overload was observed in the lower roll motor, and the current value was rather lower than before.

Example 2 Table 2 shows the steps of the product cut surface by the double side shear and the slitter when the steel plate was cut under the conditions shown in Table 1 by the steel plate shearing equipment shown in FIG. In Table 2, for comparison, when the upper roll of only the input side pinch roll of the shearing equipment is not driven (idling) among the input side, intermediate, and output side pinch rolls (Comparative Example 1), When the upper rolls of the side and middle pinch rolls are not driven (idling) (Comparative Example 2)
And the conventional method of driving all the upper and lower rolls of each of the entrance side, middle, and exit side pinch rolls.

As is clear from the results shown in Table 2, in the conventional example, both the side shear and the slitter have large steps, whereas only the inlet side pinch roll of the shearing equipment is idled while the upper roll is not driven (comparative example). 1), a decrease in the step of the top part of the steel plate was observed, and when the upper roll of the entrance side and the middle pinch roll was idled without driving, the step of the steel plate as well as the bottom part decreased. It was observed. Then, in the case of the present invention in which the upper rolls of the pinch rolls on the entrance side, the intermediate side, and the exit side are driven non-drivingly, the step difference between the top portion and the bottom portion of the steel sheet is 0.5 mm or less, which is the target. You can see that it can be cut accurately. This indicates that the main cause of the meandering of the steel plate is the difference in the driving torque of the upper roll, and that the present invention is an effective method for improving the cutting accuracy of the steel plate.

[0024]

[Table 1]

[0025]

[Table 2]

[0026]

As described above, according to the method of the present invention, the difference in driving torque of the upper pinch rolls, which is the main cause of the meandering of the steel sheet, can be eliminated, so that the steel sheet is meandered when it is cut. It has an excellent effect that it can be conveyed straightly without being stepped and a double side shear and a slitter can cut a steel plate with high accuracy. In addition, the method of the present invention can eliminate the step difference of the steel plate by simply modifying the existing shearing equipment, can manage the roll diameter difference only with the lower roll, and it is expected that the lower motor will be overloaded during heavy load transfer. In this case, there is an advantage in that the clutch can be operated to drive and convey the upper roll, which is extremely useful.

[Brief description of drawings]

FIG. 1 is a schematic plan view of a steel plate shearing equipment shown as an embodiment of the method of the present invention.

FIG. 2 is a schematic side view showing an entry side pinch roll in the above shearing equipment.

FIG. 3 exemplifies means for investigating the meandering of a steel plate in Example 1 of the present invention, and is a schematic view showing means for measuring a compressive stress acting on a bracket of an entry side pinch roll of a double side shear.

FIG. 4 is a diagram showing a transition of a bracket stress measurement value measured by the method shown in FIG. 3 and a current measurement value of a drive motor of each pinch roll.

FIG. 5 is a schematic plan view showing an example of a conventional steel plate shearing equipment to which the present invention is applied.

FIG. 6 is a schematic side view showing an entrance-side pinch roll in the above shearing equipment.

FIG. 7 is a plan view of a steel plate showing a general steel plate step state with some omitted.

[Explanation of symbols]

 1 Steel Plate 2 Double Side Shear 3 Slitter 4a Inlet Pinch Roll 4b Intermediate Pinch Roll 4c Outlet Pinch Roll 4-1 Upper Roll 4-2 Lower Roll 6-1 Upper Roll Drive Motor 6-2 Lower Roll Drive Motor 7-1 Upper Roll side reducer 7-2 Lower roll side reducer 8-1 Upper roll shaft 8-2 Lower roll shaft 9 Fluid pressure cylinder 10 Connecting shaft 11 Clutch 12 Pinch roll bracket 13 Stress measuring device

Claims (1)

[Claims] 1. A steel plate shearing line having a double side shear,
A pair of upper and lower pinch rolls that are driven by sandwiching both ends of the steel sheet in the width direction from above and below, with slitters arranged adjacent to each other, arranged on the double side shear entry side, between the double side shears and slitters, and on the slitter exit side. In a facility that intermittently conveys a steel plate in the longitudinal direction to shear the steel plate, a clutch is provided on the upper roll drive shaft of the pinch roll to make the roll idle, and when the steel plate is conveyed, the upper roll of the pinch roll. A method of transporting a steel sheet in a steel sheet shearing equipment, wherein the steel sheet is brought into idling contact and only the lower roll is driven to feed the steel sheet at a constant size.