JPS6399168A - Grinding device for steel belt edge - Google Patents

Abstract

PURPOSE:To perform proper grinding, by calculating a grinding amount from a preset value of quality of ground material, its plate thickness and edge shape and outputting a grinding amount instruction to a grinding control device while a grinding wheel peripheral speed instruction to a variable speed control device on the basis of the calculated grinding amount. CONSTITUTION:A grinding amount arithmetic device 14 calculates an adequate grinding amount and grinding wheel peripheral speed on the basis of a steel belt material 15, plate thickness 16, edge shape 17 and a steel belt moving speed 18. A fixed current control device 8 controls a motor 9 in accordance with a grinding amount instruction by a load current detection value by a load current detector 5 and a vibration frequency removing circuit 13, and a grinding wheel 3 is pressed to a steel belt 1 through a spring 10. While a grinding wheel peripheral speed instruction is given to a variable speed control device 6 through a rotary speed arithmetic device 21, and rotation of a motor 4 is controlled by a detection signal 20 of a grinding wheel diameter and a signal 11 of a rotation detector 7. In this way, proper grinding can be performed by suppressing unevenness of the grinding amount to a minimum limit.

Description

[Detailed description of the invention]

"Industrial Application Field" The present invention relates to a copper strip edge grinding device. ``Prior Art'' A problem when cold rolling stainless steel hot coils without trimming is that edge cracks occur due to minute microcracks at the edges. In order to remove the microcrank of this real coil, −
As an example, take a hot coil on the line from the edge to 0.
5 If n+ grinding is performed, a base plate with a thickness of 4.5 mm will be reduced to 0.4 mm.
It becomes possible to roll products as thin as ~0.7+n without intermediate annealing, and the yield is greatly improved. Possible methods for removing this microcrank include fusing, cutting, etc., but the best method is a grinding method that uses a disc-shaped grindstone and arranges its rotating shaft parallel to the direction of travel of the hot coil. The applicant had previously proposed a grinding device according to Japanese Patent Laid-Open No. 60-62464. This will be explained with reference to FIG. In the figure, while the steel strip 1 is continuously progressing in the direction of the arrow, the side edge (cutting/notching) of the steel strip 1 is ground by a rotary whetstone 3. For example, the rotary whetstone 3 is Through
These rotating grindstones 3 are rotated by a grindstone drive motor 4.
and the grindstone drive motor 4 is placed on the grindstone operation base 2,
Although it is movable back and forth, the grindstone operation base 2 is attached to the steel strip 1.
A pressing spring 10 is interposed between the rotating grindstone 3 and the advancing/retracting operation system, and is suspended from a fixed member by a suspension spring (not shown). In other words, due to the soft touch, the vibration of the steel strip 1 escapes using the pressing spring 10 as a cushion, which has the effect of reducing fluctuations in the grinding load current. Here, the pressing spring 10 has one end fixed to the advancing/retracting operation system (a screw nut assembled to the screw of the motor 9 in a non-rotating manner), and the other end is brought into contact with the grinding wheel operating base. The normal rotation causes the grindstone operation base 2 to move back and forth softly through expansion and contraction. Fluctuations in the load current of the grindstone drive motor 4 are reduced by the above-mentioned soft touch, but by combining a variable resistor and a variable capacitor with respect to the detection signal of the load current detector 5, it is possible to cut frequencies in a specific range without outputting them. Fluctuations can be further reduced by passing the signal through the vibration frequency removal circuit 13 having the function. In other words, in addition to the grinding load fluctuations, the load current of the grindstone drive motor 4 is superimposed on the natural vibrations of the steel strip 1 and the grindstone operation base 2 during grinding, so the load current of the grindstone drive motor 4 is detected by the detector 5 as a voltage. The converted detection signal is passed through the vibration removal circuit 13 to remove excess frequency components, and is input to the constant current control device 8 as a detection signal of only the original grinding load current. The constant current control device 8 compares the above detection signal with the set value signal of the grinding current, and controls the grinding wheel operation motor 9 based on the result.
The control signal is used to rotate the grinding wheel operating motor in forward and reverse directions. By eliminating the solid vibrations as described above, even if the side edge grinding of the steel strip 1 is performed in a state of severe vibration, highly accurate (±5%) constant current control can be realized. Therefore, when grinding the side edge of a steel strip while it is running, it is possible to advantageously avoid fluctuations in the load current of a grindstone drive motor due to disturbances caused by the running of the steel strip, and eliminate uneven grinding caused by the fluctuations. Can be done. ``Problems to be Solved by the Invention'' However, even with a grinding device having a cooking configuration, grinding is not carried out suitably, as described below. In other words, the amount of grinding (cutting depth) of the steel strip edge is considered to be proportional to the grinding current when the steel strip moving speed is constant, and the grinding current is controlled to be constant, and the setting of the grinding current is determined by the operator. Since this is done manually, the following problems arise. (1) Since the operator sets the amount of grinding, that is, the grinding current, based on experience, there were variations in the amount of grinding due to over-grinding or under-grinding. (2) Initially, grinding was performed using a set value of grinding current, and the set value was sometimes corrected based on the result, so there was variation in the amount of grinding within the same steel strip. (3) Correcting the set values increased the burden on the operator. To explain in more detail, in a grinding device using a whetstone, its grinding horsepower (kW)
It is generally known that is calculated by the following formula. P-Ft-V /612,000 (kw)
−・” (1) Ft=E−△・b−v/V
(kg) ・・・・・・(2)−,=p, Grinding horsepower (
■: Grinding wheel circumferential speed (cm/m1n) F: Grinding resistance in tangential direction (kg) E: Specific grinding energy (kg - crn/era) Δ
: Depth of cut (cm) b : Front width of g (cm) V : Feeding speed of material to be ground (am/m1n) Using this grinding device, we want to ultimately keep the depth of cut: △ constant. For this reason〔
Substituting the formula 2] into the formula [1] and finding the depth of cut: △, △= P・612.000/E-b-v (cm
) ”-・(3) Here, the grinding width: b is considered to be a constant since only one type of grindstone is normally used. Therefore, the depth of cut: △ is △= K,・P / E-v (cm)
--(4)',' K+: Constant (= 612.000
/b), and it can be seen that it is proportional to the grinding amount P, and inversely proportional to the specific grinding energy: E, and the feed rate of the material to be ground: V. Therefore, in order to keep the depth of cut △ constant, it is necessary to control the grinding amount P in order to keep P/E·V constant in equation [4]. The amount of grinding P can be expressed by the formula [5]. P = Kz-T-N (kw) --(5
)', 'Kt: Constant (= 1/973) T: Grinding wheel shaft generated torque (kg-m) N: Grinding wheel rotation speed Cr-p-m) Also, the grinding wheel shaft generated torque: T is the current of the grinding wheel drive motor: ■Because it is proportional to. P = Kz, I・N (kw) −・
...(6)', °: Constant I: Current of the grindstone drive motor (A) Here, if the grindstone rotation speed: N is constant,
Grinding amount crab P is P # K+, I (kw)...
・[7] ゛, ゛ now: constant (-3.N). Therefore, the depth of cut: can be expressed by equation [8]. △= Ks-1/ E-v (am) ・”=
(8)',' KG: constant, ・K+) For actual control, the current of the grindstone drive motor:
8] Transformed the formula

[9] This is a method in which the current is set using the formula and constant current is controlled by the grinding control device. ■＃Δ−E−v/K (A)・・・・・・
・(9) Conventionally,

[9] In formula △・E / Ks
= a, and the operator adjusted the ratio: a by checking the grinding situation or by making a judgment based on experience. For this reason, variations in the depth of cut between operators or excess or deficiency of the depth of cut due to poor adjustment have occurred. In addition, the grinding device shown in Fig. 3 does not have compensation for gradual reduction of the grinding wheel, and if the material to be ground is soft,
If the circumferential speed of the grinding wheel is high, burrs will occur on the front surface of the kat, leading to local wear of the rolling coal in the next rolling process. On the other hand, a grinding device for grinding is usually installed at a so-called stop line, and the steel strip may stop during the course of grinding the steel strip. When stopped, the steel strip moving speed signal becomes zero, so the grindstone operation base 2 reverses the grindstone operation motor 9 to move the rotary grindstone 3 away from the steel strip 1, and is moved backward. However, since the grindstone operation base 2 is positioned via the pressing spring 10, even if the grindstone operation motor 9 is reversed,
The weighing wheel operating base 2 corresponding to this movement does not retreat. Therefore, even if the steel strip 1 is stopped, the rotary grindstone 3 is in contact with the edge, resulting in over-grinding at that part.
This will cause cracks in the next rolling process. Currently, the grinding wheel operating base 2 is retracted early by detecting that the SA band moving speed has fallen below the appropriate speed of approximately 1 to 20, but the grinding wheel operating base 2 is 2, over-grinding is unavoidable due to the slow retreat time. Also,
The amount of retraction of the grindstone operation base 2 is set to a sufficient amount in consideration of the maximum compression amount of the grindstone operation base 2 pressing spring 10. Therefore, the next time the steel strip 1 begins to move, the grinding wheel operation base 2 moves forward, but the forward speed is slow, and it takes time until the rotating grinding wheel 3 comes into contact with the edge surface of the steel strip and secures the proper amount of grinding. ,
The edge portion of the steel strip that has moved at this time becomes unground or insufficiently ground, which may lead to breakage of the steel strip 1 in the next rolling step. Regarding the above point, since the rotation speed of the grinding wheel base operating motor 9 is limited by the specified rated rotation speed, it is impossible to increase the forward and backward speed any further, and the speed of the steel strip 1 is limited. It may be possible to lengthen the acceleration/deceleration time and set it to a time that allows the grinding wheel operation base 2 to move back and forth.
Prolonging the acceleration/deceleration time may reduce productivity and is not practical. ``Means for Solving Problems'' and ``Operations'' The present invention was made in view of the circumstances of cooking, and its gist is that in the grinding device, the material, plate thickness, By adding a grinding amount calculation device that calculates and outputs an appropriate grinding amount and grinding wheel circumferential speed by inputting side edge shape information, it is possible to reduce variations in grinding amount between individual operators and improve the accuracy of the grinding wheel. The point is that we have compensated for gradual decline. In addition, a cylinder with a short operation time, which can significantly shorten the contact and separation operation time by moving it forward and backward by a certain amount, is added to the pressing spring mounting base of the grinding wheel operation motor in parallel with the pressing spring, and The point is that the over-ground part is reduced. That is, in the present invention, the above-mentioned

The above problem was solved by replacing the current value determining element shown in equation [9] with a more detailed element that does not require operator judgment. The current of the grindstone drive motor in the present invention: ■ is set by the following formula. 1= f(ti f(×)・fb)・v/Ks (
A) −(io)゛,・f(t): Function determined by the thickness of the material to be ground f(x): Function determined by the shape of the side edge (G): Function determined by the material of the material to be ground Above, f
(tl can be found by setting the thickness of the material to be ground as is. Also, f (X) is the shape of the side edge of the material to be ground. In other words, it is determined by the degree of microcracks. f (tl is the specific grinding energy determined by the material. Therefore, in the present invention, f ( tl, f (X). By providing a calculation device that performs the calculation of f (current calculation and grindstone drive motor current;
When the material to be ground is soft and the circumferential speed of the grinding wheel is high, burrs will occur on the grinding surface, leading to local wear of the rolling rolls in the next rolling process. For this reason, the present invention provides a grindstone variable speed control device and a rotation speed calculator for changing the circumferential speed of the grindstone depending on the material. Note that the peripheral speed of the grinding wheel depending on the material is calculated in a grinding amount calculating device. In other words, the latter can be achieved by providing a system that controls the grinding wheel urging force to a constant value and a system that controls the grinding wheel circumferential speed to a constant value, and using a motor that increases or decreases the motor rotation speed by increasing or decreasing the motor voltage, etc. The former is achieved by using the above-mentioned motor in which the torque increases or decreases by increasing or decreasing the motor current. In addition, a quick close/open mechanism using cylinders arranged in parallel to the pressing spring body minimizes ungrinding and over-grinding caused by delays in the forward and backward movement of the grinding wheel operating motor when the steel strip moves or stops. That's what you get. "Example" This will be explained in detail below based on the drawings. 1 shows a grinding apparatus according to the first invention of the present application, and the same components as those shown in FIG. 3 are given the same reference numerals. In the figure, the load current of the grinding wheel drive motor 4 is
varies depending on the amount of grinding. This load current is fed back to the constant current control device 8 by the load current detector 5 via the vibration frequency removal circuit 13. On the other hand, a grinding wheel base forward/backward movement signal 12, which is a command for the amount of grinding, is output from a grinding amount calculating device 14 added in the present invention. The grinding amount calculation device 14 outputs the copper strip material signal 15. Steel strip thickness signal 1
6. Steel strip edge shape signal 17. and the steel strip moving speed signal (this signal has already been considered in JP-A No. 60-062464)18, an appropriate amount of grinding is calculated internally, and the grinding current command is sent to the grinding wheel. The base forward/backward movement signal 12 and the grindstone circumferential speed command are output as the grindstone circumferential speed signal 19, respectively. Note that the signals other than the steel strip moving speed signal 18 input to the grinding amount calculating device 14 are set before the steel strip 1 is ground, or are linked to the production control computer and input directly. If the latter input method is used, it is possible to set an appropriate amount of grinding without involving the operator at all. Further, in the grinding apparatus of the present invention, a variable speed control device 5 and a variable speed control device 6 are added in order to keep the circumferential speed of the rotary grindstone 3 constant. This is because the grinding wheel wears out due to continuous grinding.
If the grindstone drive motor 4 rotates at a constant speed, the circumferential speed of the grindstone will decrease, and as a result, the amount of grinding will decrease, so this is added to create a condition where the circumferential speed is constant. The range of use of the grindstone is 405 to 290*mφ. Also, the conditions of the steel strip,
In particular, a better ground surface can be obtained by changing the circumferential speed of the grinding wheel depending on the material (if the circumferential speed is too high, burrs will occur on the grinding surface and locally damage the rolling roll during rolling), so the grinding amount calculation device 14 to the grinding wheel circumferential speed signal 19 to the rotation speed calculator 21
From this and the grindstone diameter detection signal 20 (the grindstone diameter can be continuously detected by the grindstone wear amount detection device disclosed in Utility Model Publication No. 59-9812 filed by the present applicant), the rotation speed command 22 is obtained. It calculates and changes the circumferential speed of the grinding wheel. Note that 11 is a rotation detection signal of the grindstone drive motor. FIG. 2a shows a grinding apparatus according to a second invention of the present application, and the same components as those shown in FIGS. 1 and 3 described above are given the same reference numerals. As is clear from the figure, the difference from the one in Figure 1 is that the cylinder 26
The cylinder rond of the cylinder 26 operates only when the cylinder 26 is opened or closed as shown in FIG. The distance between the opposing stoppers in the figure is set to 201 m, for example. In the case of the one shown in FIG. 1, the rotation of the grindstone operating motor 9 does not directly correspond to the forward and backward movement speed of the grindstone operating base 2. This is because a pressing spring 10 is interposed between the grinding wheel operating base 2 and the grinding wheel operating motor 9. Normally, during grinding, this spring 10 is in a compressed state, and when the steel strip 1 starts to decelerate, the steel strip moving speed increases. The signal 18 decreases as the speed of movement decreases. As a result, the grinding amount calculation device 14 calculates and outputs the grindstone operation base forward/backward movement signal 12 according to the steel strip moving speed, and accordingly the grindstone operation motor 9 moves backward in this case. However, since the pressing spring 10 is interposed, the rotating grindstone 3 is in contact with the edge of the steel strip 1 until the spring 10 reaches its free length, and even if the steel strip 1 stops, it may still be in contact with the edge of the steel strip 1. In this case, the same edge portion is ground, resulting in over-grinding. However, in the case shown in FIG. 2a, the steel strip movement stop discriminator 23 determines that the steel strip has stopped, and issues a cylinder operation command 24 to move the cylinder 26 in the backward direction via the cylinder drive device 25. make it work. Since the steel strip 1 is thereby stopped, the rotary grindstone 3 can be instantly separated from the edge of the steel strip 1, so that the above-mentioned over-grinding can be suppressed to a minimum. Furthermore, when the steel strip 1 stops, in the one shown in FIG. 1, the grindstone operation motor 9 is forcibly reversed and retreated a certain distance. Therefore, the next time the steel strip 1 starts to accelerate, the grinding wheel operating motor 9 is moved forward, but the steel strip 1 accelerates quickly.
When the rotating grindstone 3 hits the edge of the steel strip 1, the grinding amount calculation device 1
It takes a considerable amount of time to achieve the appropriate amount of grinding from step 4. Therefore, the edge portion passed through during that time becomes unground or insufficiently ground. However, in the case shown in FIG. 2a, the cylinder 26 described above is operated in the forward direction so that the rotary grindstone 3 instantly hits the edge surface of the steel strip. However, if the rotating whetstone 3 suddenly comes into contact with the steel strip 1, the whetstone may be damaged.
Although the forward speed of the cylinder 26 cannot be made very high, it is much faster than the forward movement by the grindstone operating motor 9, and as a result, the number of unground and over-ground areas is reduced. "Effects of the Invention" As described above, according to the present invention, the grinding current value is not set simply by experience, but by appropriately subdividing the setting items, the material of the abrasive material, plate thickness, edge shape, steel strip movement, etc. Speed information can be set or input from the host production control computer, and the gradual reduction of the grinding wheel can be compensated for, minimizing variations in the amount of grinding caused by the operator and variations in the speed of the steel strip. As a result, steel strip breakage in the next step of cold rolling can be minimized. In addition, even if the steel strip is stopped during the steel strip grinding, over-grinding at the stopped portion and unground and under-ground portions that occur when the steel strip begins to move are minimized, resulting in a reduction in cold rolling in the next process. Steel strip breakage at

[Brief explanation of the drawing]

1 and 2a are explanatory diagrams of the steel strip edge grinding device of the present invention, FIG. 2 is an enlarged detailed view of the part indicated by the arrow in FIG. FIG. 2 is an explanatory diagram of a grinding device. 1... Steel strip, 2... Grinding wheel operation base, 3...
Rotary grindstone, 4... Grindstone drive motor, 5... Load current detector, 6... Variable speed control device, 7... Rotation detector, 8... Constant current control device, 9... Grinding wheel operating motor, 10... Pressing spring, 12... Grinding wheel operating base forward/backward movement signal, 13... Vibration frequency removal circuit, 14... Grinding amount calculation device, 15... Steel strip material signal, 16... Steel strip thickness signal, 17... Steel strip edge shape signal, 18... Steel strip moving speed signal, 1
9... Grinding wheel peripheral speed signal, 20... Grinding wheel diameter detection signal,
21... Rotation speed calculator, 22... Rotation speed command,
23... Steel strip movement, stop discriminator, 24... Cylinder operation command, 25... Cylinder drive device, 2
6...Cylinder.

Claims (2)

[Claims] (1) A grindstone operation base on which a rotary grindstone and a grindstone drive motor for driving it are mounted and supported floatingly by a spring body, and a grindstone operation base that is pressed against the steel strip edge via the spring body. A constant current motor that is equipped with a grindstone operating motor that moves forward and backward at right angles to the running direction, detects the load current of the grindstone drive motor, inputs the detection signal to a vibration removal circuit, and controls the current based on its output signal and set value signal. Settings for setting the grinding material material, plate thickness, and edge shape in a steel strip edge grinding device using a rotary grindstone, which is characterized in that a grindstone operation motor is controlled using an output signal of a control device as an operation motor control signal. A grinding amount calculation device that calculates the grinding amount from the set value and outputs an appropriate grinding amount command to a grinding control device and a grinding wheel circumferential speed command to a variable speed control device. Strip edge grinding device. (2) A grindstone operation base on which a rotary grindstone and a grindstone drive motor for driving it are mounted and supported floatingly by a spring body; A constant current motor that is equipped with a grindstone operating motor that moves forward and backward at right angles to the running direction, detects the load current of the grindstone drive motor, inputs the detection signal to a vibration removal circuit, and controls the current based on its output signal and set value signal. Settings for setting the grinding material material, plate thickness, and edge shape in a steel strip edge grinding device using a rotary grindstone, which is characterized in that a grindstone operation motor is controlled using an output signal of a control device as an operation motor control signal. A grinding amount calculation device is installed, which calculates the grinding amount from the set value, and outputs an appropriate grinding amount command to the grinding control device and a grinding wheel circumferential speed command to the variable speed control device. This steel is characterized by minimizing ungrinding and over-grinding caused by delays in forward and backward movement of the grinding wheel operating motor when stopped by providing a quick close/open mechanism with a cylinder attached in parallel to the spring body. Strip edge grinding device.