JPH089088B2 - Mold actuator for continuous casting equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold actuator for appropriately vibrating a mold provided in a continuous casting machine.

[0002]

2. Description of the Related Art As a device for continuously casting a long product having a constant sectional shape, a continuous casting device as shown in FIG. 5 is known. This apparatus is configured to continuously inject the molten metal A from the bottom of the tundish 1 into a mold (mold) 2 having the same contour as the product, and pulls the solidified casting B that has left the mold 2 while solidifying it. By doing so, the desired product is obtained.

The mold 2 is provided with an actuator 3 for giving a predetermined vibration (oscillation) to increase the cooling capacity of the mold 2 and to prevent an accident in which the casting B is seized or cut in the middle. It is designed to prevent it. A plurality of actuators 3 are attached to support the mold 2 on both sides, and are driven in synchronization by the control device 4.

An electric hydraulic pulse (servo) cylinder operated by a stepping motor is applied to such an actuator (Japanese Utility Model Publication No. 58-10004).

As shown in FIG. 6, in this device 5, a hollow piston 7 and a rod 8 are housed in a cylinder body 6, and a screw 9 and a spool 10 screwed to the screw 9 are accommodated in the rod 8. It is provided and configured.

A plurality of annular grooves 11 are formed in the spool 10, and the oil passages 12 and 1 that properly engage with the grooves 11 are formed.
By providing the pistons 3 and 14 on the piston 7 and the rod 8 so that the spool 10 that moves in the axial direction by the rotation of the screw 9 switches the oil passages 12 ...
By making a pressure difference between both ends of the piston 7, the piston 7 can slide, and the rod 8 can be driven without generating a reaction force on the screw 9 side. A supply oil port 15 and a return oil port 16 communicating with the oil passages 12 ... 14 are formed in the cylinder body 6 and are connected to a hydraulic pressure supply source (not shown).

By connecting the stepping motor 17 that rotates in proportion to the number of pulse signals to the screw 9, the amplitude and frequency of the rod 8 can be precisely controlled, and desired continuous casting can be achieved. It was

[0008]

In the recent continuous casting, in order to improve the production efficiency, even if the mold 2 is damaged in the casting process, it is not repaired in the installed state but immediately replaced by another one. It is becoming increasingly common to replace the mold with a new mold and continue casting.

However, when the above-mentioned conventional electro-hydraulic servo cylinder 5 is adopted as the actuator, the rod 8 and the spool 10 thereof are set at the origin (the most degenerate position) which serves as a reference for new vibration control of the replaced mold 2. It was difficult. That is, when positioning these at the origin, it is considered that the origin is reached when the stepping motor 17 is commanded to descend and the rod 8 comes into contact with the inner end portion of the cylinder body 6 and loses synchronization. But,
The stepping motor 17 causes jumping in which the stepping motor 17 rapidly rotates in the opposite direction at the time of step-out, which causes the spool 10
Deviation from the spool origin will occur.

For this reason, conventionally, it is necessary to measure the position of the tip of the rod 8 with high accuracy by using a level or the like to confirm that the actuator (the rod 8 and the spool 10) is set at the origin position. There is a problem that it takes a long time to set the replaced mold 2.

In view of the above circumstances, the present invention was devised to provide a mold actuator for a continuous casting apparatus that can be easily and quickly set to the origin position.

[0012]

According to the present invention, in a mold actuator provided in a continuous casting machine for appropriately vibrating a mold, the rotation of a stepping motor is converted into a linear displacement of a valve spool, and this displacement is generated. Inversion angle of the electro-hydraulic servo cylinder that moves the piston rod connected to the mold by appropriately increasing the hydraulic pressure between the piston ends and the stepping motor that separates the spool from the spool origin when the piston rod is moved to the origin position. An angle sensor for detecting the angle, and a control means for calculating a correction pulse value for moving the spool to the spool origin based on the detection value of the angle sensor and outputting the pulse to the drive unit of the servo cylinder. Be prepared.

[0013]

With the above construction, when the stepping motor is rotated, the electrohydraulic servo cylinder converts this rotation into the linear displacement of the valve spool and the boosting movement of the piston rod to perform a predetermined vibration output. The angle sensor detects the reversal angle due to the jumping of the stepping motor when the piston rod and the spool are positioned at the origin, and inputs this to the control means. Based on this angle, the control means calculates a correction pulse value for positioning the spool at the spool origin, and commands the servo cylinder to rotate by the amount of this pulse.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of a mold actuator of a continuous casting apparatus according to the present invention, in which the same components as those in the prior art are designated by the same reference numerals.

This mold actuator is connected to the mold 2 by converting the rotation of the stepping motor 17 into a linear displacement of the valve spool 21 and increasing the hydraulic pressure between both ends of the piston caused by this displacement appropriately, as in the conventional case. An electro-hydraulic servo cylinder 23 for moving the piston rod 22, and an angle sensor for detecting the reversal angle of the stepping motor 17 for separating the spool 21 from the spool origin when the piston rod 22 is moved to the origin position (synchro oscillator). ) 24 and the angle sensor 24
And a controller 26 which is a control means for calculating a correction pulse value for moving the spool 21 to the spool origin and outputting this pulse to the drive unit (drive unit) 25 of the stepping motor 17 There is.

The stepping motor 17 has its output shaft 2
The gear 28 attached to 7 is meshed with the gear 31 attached to one end of the screw 30 projecting outward in the axial direction of the cylinder body 29, and the output rotation thereof causes the screw 30 to rotate about the axis. , The valve spool 21 moves in the axial direction, and the movement causes the oil passages 32, 33, 34 to be switched, and the cylinder body 2
The piston 35 and the piston rod 22 are moved by appropriately generating a hydraulic pressure difference within the mold 9, and the mold 2 is appropriately vibrated.

Further, the piston 35 and the piston rod 22
A screw chamber 36 in which the screw 30 is housed
A spool chamber 37 having a larger diameter than that is defined, and the spool 21 is configured to move (up and down) in the axial direction within the range of the spool chamber 37. Therefore, the origin position of the piston rod 22 is in a state where the piston 35 is in contact with the lower end inner wall 38 of the cylinder body 29, and at that time, the lower surface 39 of the spool 21 is seated on the lower end inner wall (spool end) 40 of the spool chamber 37. When it does, the spool origin position is reached.

The angle sensor 24 is arranged in parallel on the opposite side of the stepping motor 17 with the screw 30 interposed therebetween, and has a gear 41 that meshes with a gear 31 on the screw 30 side. That is, the rotation angle of the stepping motor 17 is detected by the rotation of the gear 41. This angle signal α is converted by the converter 42 into the spool 21.
After being converted into a linear numerical value corresponding to the moving distance of, the value is input to the controller 26. Therefore, when the stepping motor 17 causes jumping during step-out, the reversal angle αx is detected and the deviation amount X of the spool (the distance between the spool lower surface 39 and the spool end 40) is input. Become. The controller 26 calculates the pulse value f by the following equation based on the input deviation amount X.

Fx (pulse) = X (mm) ÷ L (mm / pulse) where fx; correction pulse signal X; deviation amount L; servo cylinder resolution Therefore, in the servo cylinder 23 with a resolution L of 0.01 mm, the deviation amount When X is detected as 0.05 mm, the correction pulse signal fx is calculated as 5 pulses. Note that the stepping motor 17 is a 5-phase motor (2-, 3-phase excitation system, 1 for 10 pulses).
If it is rotation, inversion (jumping) corresponding to 0 to 5 pulses is expected at the time of step-out. An output unit (not shown) of the controller 26 is connected to the drive unit 25 of the stepping motor 17, and the calculated correction pulse signal fx is equivalent to the excitation pulse signal Fx.
And is input to the stepping motor 17.

In addition, in the present embodiment, the return oil port 43 provided in the cylinder body 29 communicates with the oil passage 34 that extends radially in the recessed outer peripheral surface portion of the piston 35. And is connected to a hydraulic pressure source (not shown) together with the supply oil port 44.

Next, the operation of this embodiment will be described with reference to FIG.

When casting is performed by the continuous casting apparatus, setting conditions for obtaining a desired vibration (amplitude and frequency) are input to the controller 26, and a stepping motor is generated according to a pulse signal f from the controller 26. 17 is rotationally driven. As shown in FIG.
By this rotation, the valve spool 21 is linearly displaced, the oil passages 32 ... 34 are appropriately switched, a desired hydraulic pressure is generated, and the piston rod 22 reciprocates to move the mold 2
Vibrate.

When the mold 2 is damaged and needs to be replaced,
When positioning the servo cylinder 23 at the origin, first, to lower the piston rod 22 to the origin position,
The controller 26 outputs the falling pulse f ₀ to the stepping motor 17 (ST 1 in FIG. 4). This command is executed until the spool 21 reaches the spool end 40, that is, until the stepping motor 17 loses step (ST.
2).

When the spool 21 reaches the spool end 40, the falling pulse f ₀ is immediately stopped (ST 3) and the angle sensor 24 detects the rotation angle α of the stepping motor 17 (ST 4). The detected rotation angle α signal is sent to the controller 26 via the converter 42. If this rotation α is in the opposite direction (αx) to the descending direction, there is jumping (reversal) of the stepping motor 17. It is determined that the spool 21 is separated from the spool end 40 (ST5), a correction pulse fx corresponding to this reversal angle αx is calculated (ST6), and this is output to the stepping motor 17 (ST7). ). Stepping motor 1
7 rotates the spool 21 to the lower side by the angle corresponding to the correction pulse fx to move the spool 21 to the spool end 40 (ST8).

As shown in FIG. 3, the spool 21 is now in the original posture when it is seated on the spool end 40, and the mechanical original point and the electric control reference point are correctly aligned.

Thus, the angle sensor 2 for detecting the reverse rotation of the stepping motor 17 in the gear 31 of the screw 30.
4 is provided, and the controller 26 applies the correction pulse fx for lowering the reversal angle αx by the stepping motor 17
Since it is configured to output to the stepping motor 1
Even if an error occurs in the origin position of the spool 21 due to jumping during step-out that occurs due to the function of No. 7, it can be easily corrected and set to a precise mechanical origin. That is, the control reference of the mold actuator required when the mold 2 is replaced can be quickly obtained, and continuous casting can be restarted immediately, which can contribute to the improvement of productivity.

Although only one actuator is shown in FIG. 1, since the mold is equipped with a plurality of mold actuators, the origins are naturally adjusted in the same manner.

The angle sensor is not limited to this embodiment, but may be configured to directly detect the rotation of the output shaft of the stepping motor, for example.

Further, in FIG. 4, the rotation of the stepping motor is detected after the falling pulse is stopped. However, when the angle sensor constantly detects the rotation and a reversal angle different from the descending command is detected, the controller outputs the correction pulse. May be output.

[0031]

In summary, according to the present invention, the following excellent effects are exhibited.

An electro-hydraulic servo cylinder for appropriately moving the piston rod connected to the mold by the rotation of the stepping motor, an angle sensor for detecting the reversal angle of the stepping motor, and the spool origin based on the detected value. Since it has a control means that calculates the correction pulse value for moving to the servo cylinder drive part and outputs it to the drive part of the servo cylinder, even if there is an error in the control origin due to jumping of the stepping motor, it is easy It can be set, and mold replacement and continuous casting restart can be done quickly, contributing to improved productivity.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a mold actuator of a continuous casting apparatus according to the present invention.

FIG. 2 is a side sectional view showing a state where the piston rod of FIG. 1 is moving.

FIG. 3 is a side sectional view showing a state where the spool of FIG. 1 is located at the origin.

FIG. 4 is a flowchart for explaining the operation of FIG.

FIG. 5 is an overall configuration diagram showing a mold actuator of a conventional continuous casting device.

FIG. 6 is a side sectional view of a conventional electrohydraulic pulse (servo) cylinder applied to the mold actuator.

[Explanation of symbols]

 2 Mold 17 Stepping Motor 21 Valve Spool 22 Piston Rod 23 Electro-hydraulic Servo Cylinder 24 Angle Sensor 25 Drive Unit 35 Piston 40 Spool Origin Spool End fx Correction Pulse Value (Signal)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hisaki Fujinaka 3-2-16 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Ltd. Toyosu General Office (72) Inventor Hiroo Oya Sanyo Toyosu, Koto-ku, Tokyo 2-16 Ishikawajima Harima Heavy Industries Co., Ltd. Toyosu General Office (72) Inventor Shiro Murakami 3-2-16 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Co., Ltd. Toyosu General Office (56) Reference JP 3 -106540 (JP, A) Actually open Sho 62-3252 (JP, U) Japanese Patent Publication No. 2-19741 (JP, B2)

Claims (1)

[Claims] 1. A mold actuator for appropriately vibrating a mold provided in a continuous casting apparatus, wherein rotation of a stepping motor is converted into linear displacement of a valve spool, and a hydraulic pressure difference between both ends of a piston caused by the displacement is appropriately increased. An electro-hydraulic servo cylinder that moves the piston rod connected to the mold to detect the reversal angle of the stepping motor that separates the spool from the spool origin when the piston rod is moved to the origin position. Of the angle sensor, and control means for calculating a correction pulse value for moving the spool to the spool origin based on the detection value of the angle sensor and outputting the pulse to the drive section of the servo cylinder. A mold actuator for a continuous casting machine.