JPS6263096A - Standard-length cutting control system of continuous travelling material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention comprises 1. The present invention relates to an improvement of a rotary running cutting device for continuously cutting a running sheet material as a material to be cut into a predetermined length using a rotary shear.

[Conventional technology]

BACKGROUND OF THE INVENTION Conventionally, rotary running cutting devices have been widely used as devices for cutting continuously conveyed materials, such as steel plates, into sheets.

FIG. 3 is a perspective view schematically showing such a conventional rotary running cutting device. In the figure, a workpiece 1 moves in the direction of arrow 2, and a rotary machine is used to cut the workpiece 1.
A sear is installed. The rotary shear consists of a pair of upper and lower cylinders 3 and cutting blades 4, and when the cutting blades engage,
A material to be cut 1 is cut. The upper and lower cylinders 3 are connected via a gear 9, and are connected via a gear 5 to a servo motor 6. A pulse encoder 8 and an analog tacho generator 7 are connected to the servo motor 6 to measure the amount of movement and speed of the rotary shear. Further, in order to detect the absolute position of the rotary shear, a proximity switch 10 is mounted on the shaft of the cylinder 3, and generates a signal of 1 pulse per rotation of the rotary shear.

The pulse encoder 12 detects the amount of movement and speed of the material 1 to be cut, and the length measuring roll 11 is in contact with the material 1 to be cut.
is combined with

When the servo motor 6 rotates, the rotary shear also rotates via the gear 5, and the upper and lower cutting blades 4 engage to cut the workpiece 1. During cutting, the speed of the workpiece 1 and the rotary shear are The cutting edge speeds are preset to match.

When the rotary shear makes one rotation and cuts the material with the cutting edge speed being equal to the material speed, the length of the cut sheet becomes equal to the cutting edge circumference (B0). When cutting into sheets shorter than the circumference of the cutting edge, after cutting the workpiece 1, the rotary shear rotates at high speed and causes the cutting blade 4 to advance, until the cutting blade 4 engages the workpiece 1 (i.e. At the point when cutting is started, the servo motor 6 is controlled to reduce the rotational speed of the rotary shear so that it becomes equal to the speed of the material 1 to be cut, and in this way the cutting edge Even when cutting sheets shorter than the circumference, cutting is performed at the synchronous speed.

Conversely, to cut a sheet longer than the circumference of the cutting edge, after cutting the material to be cut, the rotary shear is decelerated and stopped, and when a predetermined size is reached, it is accelerated, and when the cutting blade engages with the material to be cut ( In other words, at the point when cutting is started, the servo motor 6 is controlled to accelerate the rotational speed of the rotary shear so that the rotational speed of the rotary shear becomes equal to the speed of the material to be cut. Even when cutting sheets that are longer than the circumference, cutting is performed at a synchronous speed.

In this way, with conventional rotary running cutting machines, it is possible to obtain either long or short cutting lengths by varying the rotational speed of the rotary shear on the cutting machine's side, which transports the material at a constant speed. . This type of control device is disclosed in, for example, Japanese Patent Publication No. 56-41398.

Now, in the conventional rotary running cutting device as described above, it is necessary to rapidly change the speed of the rotary shear, and in order to prevent the cylinder from deflecting and twisting that occurs due to this, the cylinder diameter must be increased to provide rigidity. There is a need. For this reason, there is a drawback that the output of the servo motor needs to be increased in order to achieve a predetermined acceleration rate.

[Problem that the invention seeks to solve]

Accordingly, the present invention provides a rotary running cutting device that can obtain any cutting length, long or short, without the need to rapidly change the speed of the rotary shear, and therefore without increasing the output of the servo motor. The problem that needs to be solved is to make it possible. Therefore, it is an object of the present invention to provide a method for controlling the cutting of continuous running materials to a fixed length, which enables the above-mentioned operations.

[Means and operations for solving the problem] In order to achieve the above object, the present invention makes the rotational speed of the rotary shear constant and changes the feed speed of the material to be cut. For this purpose, a mechanically simple feed roll is added, and by changing the speed of this feed roll, the feed speed of the material to be cut can be changed. Therefore, it is not necessary to increase the output of the servo motor that drives the feed roll.

〔Example〕

The present invention will now be described in detail with reference to the drawings.

FIG. 1 is a perspective view showing the mechanical configuration of an embodiment of the present invention. In the figure, the material to be cut LA is fed at a constant speed from the direction of the arrow 2A, forming a loop 13, and the feed
After being nipped by rolls 14, it is fed into a rotary shear. Since the feed roll 14 changes the speed of the material to be cut IA, the loop 13 that absorbs the variation is constructed in front of the feed roll 14.

The feed roll 14 is composed of a pair of upper and lower rolls,
It is coupled to a servo motor 16 via a gear 15.

A tacho generator 17 is connected to the servo motor 16 for speed feedback of the servo amplifier.

The rotary shear has a pair of upper and lower cylinders 3A and a gear 5A, just like the rotary running cutting device described above.

Servo motor 6A, tacho generator 7A, pulse
It consists of an encoder 8A.

FIG. 2 is a basic circuit diagram for drive control of the feed roll 14 shown in FIG. 1. In the same figure, 8A is a pulse encoder for measuring shaft movement, 20 is a coefficient unit,
21 is a length setting device, and 12A is a pulse length measuring device for the material to be cut.
encoder, 18 is a coefficient unit, 19 is a control register, 22
is a D/A converter, 23 is a nonlinear amplifier, 25 is an analog adder, and 35 is a rotational movement tco of the feed roll 14.
(Here, the rotational movement 1co of the feed roll 14 means a stop command to the servo motor 16 that rotationally drives the feed roll 14.) This refers to the amount of rotational movement of the feed roll 14 from when the input is input until the feed roll 14 actually stops.Therefore, this amount of movement is based on the rotational speed of the servo motor at that time, the rotational speed of the servo motor at that time, 28 is a stop control register; 29 is a D/A conversion 30 is a nonlinear amplifier, 31 is a comparison circuit, 26 is a signal selection circuit, 27 is a servo amplifier, 16 is a servo motor, and 17 is a tacho generator.

The circuit operation will be explained with reference to FIGS. 1 and 2.

A pulse signal is generated from the length measuring pulse encoder 12A by the rotation of the length measuring roll IIA which is in rolling contact with the material to be cut IA. The coefficients of this pulse signal are set by the coefficient unit 18 so that, for example, 10 pulses are generated when the material moves by 1 mm, and the coefficients are input to the subtraction input of the control register 19.

On the other hand, the pulse signal from the pulse encoder 8A that measures the amount of movement of the rotary shear has a coefficient set by the coefficient unit 20 in the same way as the pulse signal for length measurement, so that the pulse signal corresponding to the amount of movement of the circumference of the cutting edge of the rotary shear is set. is generated and input to the addition input of control register 19.

The length setter 21 subtracts the cutting edge circumference (B0) of the rotary shear from the cutting length (L), converts it into a pulse corresponding to (L-B0), and if the value is positive, the control register 19 On the other hand, if the value is negative, the control register 19
is input to the subtraction input at the timing when the proximity switch IOA for detecting the absolute position of the rotary shear is activated.

After all, if the contents of the control register 19 are R, then R=(L−B
0)+A-B. Here, A is the value obtained by integrating the outputs of the coefficient multiplier 20, and is 1. B is a value obtained by integrating the outputs of the coefficient unit 18. The content of the control register 19 is a value Vc converted into an analog voltage by the D/A converter 22, and although its role will not be described in detail, it is amplified by a nonlinear amplifier 23 designed to increase the gain near OV. teVc'
becomes.

Further, the pulse signal from the pulse encoder 8A is converted into a DC voltage Va by the frequency/analog voltage converter 24, and then the output voltage of the nonlinear amplifier 23 and the analog adder 25
Then, the VO value is VO=Va +Vc'
becomes.

In addition to the output voltage (1) 0, the signal selection circuit 26 receives an analog voltage value vb, which will be described later, and selects the higher voltage value of (2) 0 or vb, and the selected output voltage consists of a DC motor. The signal is input to the servo amplifier 27 as a speed command for the servo control system including the servo motor 16 and the like.

The value of the roll rotational movement amount CO from the CO generator 35 is written into the stop control register 28 as an addition input every time a cutting completion signal is obtained from the rotary shear reference position detector 10A. Further, the pulse from the coefficient unit 18 is input to the stop control register 28 as a subtraction input when the servo motor rotates in the forward direction, and as an addition input when the servo motor rotates in the reverse direction. It becomes C0-B.

The output of the stop control register 28 is converted into an analog voltage by a D/A converter 29, and after increasing the gain near OV by a nonlinear amplifier 30, a comparison circuit 31 with Va compares it with V.
Values greater than a are input to the signal selection circuit 26 as vb values clamped to Va values.

Next, the operation of the present cutting device configured as above will be explained in the following three cases.

(a) When the set length matches BO In this case, the setting pulse from the length setter 21 is zero and the control register 19 contains the workpiece movement amount pulse and the rotary
Only the shear movement pulse is input.

At this time, Vc is adjusted so that it is almost O,
The servo motor is rotating with a signal of only Va, and the difference in the amount of movement between the material to be cut and the rotary shear is determined by the control register 19.
The value is stored in Va and superimposed on Va as a correction value, and speed synchronization control is performed at all times.

Since Vc is almost the same at each cutting timing, the material to be cut is cut at BO.

(11) When the set length is shorter than BO, the cutting completion signal causes a pulse corresponding to (BO-L) from the length setter 21 to be written to the subtraction input of the control register 19, and the content R of the control register 19 is R=-(BO-L)+A-B
changes in a short time, and Vc takes a negative value proportional to R.

The output ■0 of the adder 25 becomes a value smaller than Va, and V
If c is a sufficiently large value, it will also be negative.

The content R' of the stop control register 28 becomes positive as R'=C0-B, the signal selection circuit 26 selects vb, and the servo motor 16 performs servo control to decelerate and stop in accordance with the change in vb. When the servo motor decreases compared to the speed of the rotary shear and the amount of change in B is smaller than A, the content R of the control register 19 approaches zero, and the values of Vc and Vc' simultaneously approach zero. (2) 0 becomes a larger value than vb, the signal selection circuit 26 selects VO, and the servo motor accelerates again. Even during acceleration, since the amount of change in B is smaller than that in A, the speed is accelerated until the speeds of the rotary shear and the servo motor match, that is, until Vc becomes almost zero. V of command voltage (Va +Vc)
Most of the rotation is made with only the signal a, and cutting is performed.

The fact that Vc is zero means that the content R of the control wholesale register 19 is zero, and -(BO-L)+A-B=0. Here, the amount of change in A from the completion of cutting to the completion of the next cut is B
Since it is O, L-B=0 after all. That is, it means that the cut sheet length B is equal to the set length.

(c) When the set length is longer than BO In this case, a pulse corresponding to (L-B0) is written to the addition input of the control register 19, and the content R of the control register 19 is R=L-BO+A-B. is positive. ■0 is v
b, and the servo motor accelerates at the same time as the cutting completion signal is input. Since the amount of change in B is larger than that in A, R goes to zero, and the servo motor also decelerates and follows the speed to be equal to the speed of the rotary shear.The point where the cut sheet length and set length are equal is the cutting length. It is the same as when is short.

As explained above, when the movement of the feed roll 14 is proportional to the movement of the cylinder 3 of the conventional rotary shear shown in FIG.
), they are similar in the opposite relationship.

-i, since the inertia of the cylinder 3A is larger than that of the feed roll 14, a high-output servo motor 6 is required to drive the rotary shear cyclically. Since the feed roll 14 has a small inertia, a low output servo motor 16 is required for similar cyclic driving, and the extremely remarkable effect of cutting sheet material at a higher speed than before can be obtained.

〔Effect of the invention〕

As explained above, according to the present invention, in a rotary running cutting device, there is no need to abruptly change the speed of the rotary shear, which has a large inertia, and it is only necessary to change the speed of the feed roll, which has a small inertia. This has the advantage that the output of the servo motor can be reduced.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the mechanical configuration of an embodiment of the present invention;
FIG. 2 is a basic circuit diagram of the drive control mechanism for the feed roll shown in FIG. 1, and FIG. 3 is a perspective view schematically showing a conventional rotary running cutting device. Code explanation 1.1. A... Material to be cut, 3,3A... Cylinder,
4゜4A...Cutting blade, 5,5A, 9.9A...Gear, 6゜6A, 16...Servo motor, 8.8A, 1
2゜12A...Pulse encoder, 10.10A.
...Proximity switch, 11. IIA...Length measurement roll, 7
, 7A, 17... Tacho generator, 13... Loop, 14... Feed roll, 18.20... Coefficient unit, 19... Cutting control register, 21... Length setter, 22゜29...D/A converter, 23.30...
- Nonlinear amplifier, 24... Frequency/analog voltage converter, 25... Analog adder, 26... Signal selection circuit, 27... Servo amplifier, 31... Comparison circuit.

Claims (1)

[Claims] 1) A rotary shear for continuously cutting a running sheet material as a material to be cut into a predetermined length, and a feed roll for feeding the sheet material toward the shear;
In the fixed length cutting device, which cuts the traveling sheet material while rotating the rotary shear at a constant speed, the cut length setting value (L) of the sheet material and the circumference of the rotary shear (B0) is L>B0
In the case of , the feed speed of the sheet material is accelerated at the timing when the sheet material is cut each time, and when L<B0, the feed speed is decelerated at the timing, and at the time when the sheet material is started to be cut by the shear. In order to recover the feed speed so that the feed speed of the sheet material matches the rotational speed of the shear, means for controlling the feed roll is provided, and the sheet is cut at a speed synchronous with the rotary shear. A fixed-length cutting control method for continuously running materials.