JPS60143708A - Curvature measuring apparatus in bending roll - Google Patents

Abstract

PURPOSE:To make the measurement quick, by constituting the titled apparatus by a touch roll having a specified positional relationship with a roll at the lower part of a final stage, which is contacted with a work, and a sensor roll, which can be slidden freely, and measuring the curvature of the work based on the amount of the stroke. CONSTITUTION:The axial center of a lower roll 1 for bending at a final stage is made to agree with the center of rotation of a freely rotating sensor frame 2. A touch roll 3 and a sensor roll 4 are mounted on the positions in the vicinity of the lower roll 1, which can be contacted with a work A, when the frame is rotated in the measuring and rotating direction. The touch roll 3 is made to lead the freely sliding sensor roll on the frame 2 by an angle alpha. When the frame 2 is rotated in the measuring direction and the roll 4 is contacted with the work A at the time of operation, the amount of the stroke of the roll 4 is detected and converted into the curvature of the work A. Thus the measurement can be performed accurately, quickly and continuously.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a curvature measuring device for a bending roll, and particularly to a curvature measuring device using a sensor method.

Generally, the following two methods have been conventionally considered as methods for measuring curvature in a control method for bending a workpiece such as a steel plate to a constant curvature.

The first method is to calculate the radius of curvature based on a relational expression between the curvature of the workpiece and the indentation amount of the upper roll from the material mechanical relationship (see Japanese Patent Publication No. 52-2717).

The second method is to calculate the radius of curvature by measuring three points on the workpiece based on the geometric relationship (Japanese Patent Publication No. 52-
(See Publication No. 17818).

However, in the first method, it is not easy to fully take into account unstable factors such as differences in springback amount due to differences in material and size of workpieces, and variations in tensile strength.

In addition, in the second method, since the measurement is performed in a range affected by springback, it is necessary to perform measurement after the pressing force is once removed, and continuous measurement of the radius of curvature is impossible.

Generally, in order to measure the curvature of an arc-shaped workpiece, if the positional relationship of three points on the arc is known, the radius of curvature, and ultimately the curvature of the arc, can be determined based on the so-called cosine theorem. Depending on how the measurement points are selected, a control delay may occur when automatic control is performed based on measurement signals, making it impossible to improve the accuracy of bending and causing problems such as an increase in the number of passes of the workpiece.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and provide a curvature measuring device that is not affected by springback and can obtain measurement signals as quickly as possible.

The basic configuration for achieving the above objective is as shown in FIG.

That is, a rotatable sensor frame 2 whose rotation center coincides with the axis of the lower bending roll 1 in the final stage is provided, and the touch roll 3 and sensor roll 4 are attached to the sensor frame 2 in the measurement rotation direction ( arrow a
Reference)・＼ Mount the touch roll 3 at a position where it can come into contact with a part of the workpiece A as close as possible to the lower roll 1 when rotated, and set the touch roll 3 on the sensor frame 2 so that the phase in the measurement rotation direction is higher than that of the sensor roll 4. The sensor roll 4 is provided at a position advanced by a certain angle α, and the sensor roll 4 is supported in a slidable manner (see also the arrow).

When the frame 2 is not in operation, it is at the position shown by the dashed line, and the touch roll 3 and the sensor roll 4 are both located away from the workpiece A, but when it is in operation, the frame 2 rotates in the measurement rotation direction, which is shown by the solid line. , the touch roll 3 whose phase is advanced first comes into contact with the workpiece A. From this state, only the sensor roll 4 slides in the direction of the arrow and comes into contact with the workpiece A. This invention detects the stroke amount of the sensor roll 4 in this case, and converts it into the curvature or radius of curvature of the workpiece A based on the detected stroke amount.

Next, the measurement principle according to the present invention will be explained with reference to FIGS. 2 and 3.

Figure 2 shows one upper roll 5 and two lower rolls 1.6.
This figure shows a situation where workpiece A is being subjected to bending action in a bending roll using a bending roll. In this case, the area X of the workpiece A, that is, the area between both lower rolls 1.6 is an area before plastic working, and is an area affected by springback. In addition, when measuring in range 2, that is, in a part far away from the lower roll 1, the transmission of the measurement signal required to change the suppression stroke of the upper roll 5 is delayed, and the number of passes of the workpiece A increases or the number of passes is increased more than necessary. There is a problem with pressing too hard.

However, the range y from the lower roll 1 to the above range l
If the measurement is made in the area , that is, as close as possible to the lower roll 1, there will be no effect of springback, and the measurement signal will be transmitted more quickly than in the area l. ' Therefore, in this invention, the contact point between the lower roll 1 and the workpiece A is selected as one of the three measurement points, and the other two points are selected as close to this point as possible. .

FIG. 3 shows the measurement principle in this invention.

In this case, the work A that has come into contact with the final stage lower roll 1c is represented by a circle with the radius of curvature of the range y mentioned above, and the touch roll 3 and sensor roll 4 are
It comes into contact with the work A at the point. Also,
This figure shows an X whose origin is the rotation center P0 of the lower roll 1.
This shows a state in which the touch roll 3 is in contact with the workpiece A on the axis and Y-axis coordinates. The location of each part is as follows.

Center of lower roll 1 p0 (o, o) Center of circle '+ (X+ + v+) Touch roll 3
Center Pwc Xs + Yx) Center P of the original position of the sensor roll 4, (X, , Y3) Center P4 of the sensor roll 4 after sliding (X4 + Y4) In addition, the known numerical values are as follows.

Radius of lower roll 1 r.

Distance d between lower roll 1 and touch roll 3 Radius r of touch roll 3 and sensor roll 4 (same diameter) Distance a between touch roll 3 and sensor roll 4 Tilt angle when sensor roll 4 slides (tilt angle θ is an angle tilted in the direction of the touch roll 3 with respect to a line segment y perpendicular to the line segment connecting both rolls 3.4. It is provided for contact, and may be zero if the sensor roll 4 can come into contact with the lower roll 1 at a position close to the lower roll 1 due to the structure of the sensor frame 2.) Note that the lower roll 1, the touch roll 3, and the sensor The rolls 4 are arranged so that they have a common tangent B in order to simplify the calculation formula.

From the above relationship, triangle P. P, P2 and the same P. P
Since the position on the coordinates of 2P3 can be found, sensor roll 3
Stroke lid S until it comes into contact with workpiece A.

can be expressed as a function of the radius of curvature, that is, 5t=f(R), so its inverse function 'R=f''−
1('St), the radius of curvature can be approximated.

Although it is generally difficult to determine the above-mentioned inverse function by calculation, k can be determined by graphing the calculation result of St and analyzing it to find an approximate complementary formula.

Next, an embodiment embodying the above-mentioned basic configuration will be described based on FIGS. 4 to 6.

The bending roll of this embodiment has one upper roll 5 and two front and rear lower rolls 1 and 6, and a sensor frame is placed around the front lower roll 1, that is, the final stage lower roll 1 via a guide roller 7. 2 is rotatably attached. A piston rod 9 of a hydraulic cylinder 8 for rotating the sensor frame 2 is pivotally mounted on the sensor frame 2, and the hydraulic cylinder 8 is pivotally mounted on a base 10.

A touch roll 3 is fixed to the sensor frame 2, and a sensor roller 4 is slidably attached to the sensor frame 2 by a hydraulic cylinder 11. Each of these rolls 1, 3.4
have a common tangent line B, and the touch roll 3 is located at a position that is somewhat advanced in phase from the sensor roll 4 in the measurement rotation direction (see angle α).

A magnetic scale 14 is connected to the piston rod 12 that supports the sensor roll 4 through a bracket 13. Detect the stroke amount St.

j! FIG. 6 shows a state in which the touch roll 3 is brought into contact with the workpiece A by operating the hydraulic cylinder 8.

In this state, the sensor roll 4 is not in contact with the workpiece A.

The sensor roll 4 has a constant stroke S1 from the above state.
In this case, the sensor roll 4 slides to the touch roll 3 side with respect to the line segment y perpendicular to the line segment C connecting its center and the center of the touch roll 3. is tilted by an angle θ.

In addition, in order to continuously measure the radius of curvature of the workpiece A, in order to keep the contact pressure of the touch roll 3 and the contact pressure of the sensor roll 4 constant by following the momentary changes in the radius of curvature,
The radius of curvature Ri or curvature is calculated by controlling the hydraulic cylinder 8.11 and continuously inputting the signal of the stroke St to the calculation device. The calculation results can be continuously displayed digitally.

As described above, this invention provides a final stage lower roll that contacts the workpiece, a touch roll that is in a constant positional relationship with this roll and that contacts the workpiece earlier than the sensor roll, and is further provided that is in constant position with the touch roll. It is in the positional relationship of
In addition, the sensor roll is provided with a slidable sensor roll, and the stroke amount of the sensor roll is continuously detected. This stroke amount is determined by the positional relationship of the contact points of the final stage lower roll, touch roll, and sensor roll with the workpiece, so the radius of curvature or curvature of the workpiece can be measured based on this number. can. Moreover, one of the three measurement points is set as the contact point with the final stage lower roll, and the other two points are selected as close as possible to the contact point in the plastic working area of the workpiece. It is. Therefore, since it is not affected by springback, accurate and continuous measurements can be made, and the measurement signal can be transmitted absolutely quickly, and based on that signal, automatic control with little time delay can be performed. .

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing the basic configuration of this invention, Figs. 2 and 3 are illustrations of the principle of this invention, Fig. 4 is a side view of the embodiment, and Fig. 5 is a partially omitted front view of Fig. 4. FIG. 6 is a side view at the time of measurement. 1... Final stage lower roll, 2... Sensor frame,
3...Touch roll, 4...Sensor roll, 5...
・Upper roll, 6... Lower roll, 7... Guide roll, 8... Hydraulic cylinder, 11... Hydraulic cylinder, 1
5...Detector, Patent applicant: Kurimoto Iron Works Co., Ltd. Agent: Patent attorney Fumi Kamata Figure 4 Figure 5

Claims (1)

[Claims] A rotatable sensor frame whose rotation center coincides with the axis of the lower roll for bending in the final stage is provided, and when the touch roll and sensor roll are rotated in the measuring rotation direction/\\ to the sensor frame, as much as possible The touch roll is mounted on the sensor frame at a position where it can come into contact with the work part near the lower roll, the touch roll is placed on the sensor frame at a position where the sensor roll is advanced in phase in the measurement rotation direction, and the sensor roll is supported so as to be freely slidable. Curvature measuring device for bending rolls.