JP2018144048A - Clean out controlling method for extrusion press - Google Patents

Abstract

Kind Code: A1 In a conventional extrusion press, the timing of cleanout relies on human experience and intuition. Therefore, if the cleanout operation is infrequent, the billet may be poorly inserted, leading to a decrease in billet temperature, a decrease in productivity, and unstable quality. In addition, if the cleanout operation is wastefully performed, the idle time becomes long, leading to a decrease in productivity. In a cleanout control method for an extrusion press equipped with a servomotor for driving an inserter for inserting a billet into a container, the peak value of the insertion torque of the servomotor when the inserter inserts the billet into the container, or At least one of the chatter values is detected, and when at least one of the insertion torque peak value and the chatter value exceeds the threshold, cleanout is performed. [Selection drawing] Fig. 2

Description

  The present invention relates to an extrusion press, and relates to a cleanout control method in an extrusion press.

In general, when a billet made of a metal material such as aluminum or an alloy material thereof is extruded by an extrusion press device, an extrusion stem is attached to the tip of a main ram driven by a hydraulic cylinder, and a container is pressed against a die. Then, the billet is stored in the container by the billet inserter. Then, the billet is pressed by the extrusion stem by further advancing the main ram by driving the hydraulic cylinder. Therefore, the molded product is extruded from the outlet of the die.
After pushing out the billet, the container is slightly retracted by the container cylinder, and the main ram and the container are retracted from the position where the discard is removed from the container.
Next, the cutting blade of the cutting device is fed between the container and the die, and the billet (referred to as a discard) remaining on the die surface is cut off. After that, the main ram is retracted, the extrusion stem is extracted from the container, the next billet is inserted into the container, and the next cycle of extrusion molding is started.

JP-A-6-269850

  In conventional extrusion presses, the timing of cleanout relies on human experience and intuition. Therefore, if the clean-out operation is small, billet insertion is poor, leading to a decrease in billet temperature, a decrease in productivity, and unstable quality. In addition, if the clean-out operation is performed wastefully, the idle time becomes longer, leading to a decrease in productivity.

In a cleanout control method in an extrusion press equipped with a servo motor that drives an inserter for inserting a billet into a container, at least the peak value of the insertion torque of the servo motor or the chatter value when the billet is inserted into the container with an inserter Detect one,
When at least one of the peak value of the insertion torque or the chatter value exceeds the threshold value, the cleanout is performed.

The initial operation of the cleanout uses a preset initial value as a peak value threshold,
After the initial cleanout operation, the peak value of the insertion torque of the servo motor when the first billet is inserted after the initial cleanout operation is taken as the first operation reference value, and the set multiple of the first operation reference value is the peak value threshold. As
When the insertion torque of the servo motor exceeded the peak value threshold, it was decided to perform cleanout.

  The set multiple of the first operation reference value is set to double.

In the initial operation of the cleanout, an initial value set in advance is used as a chatter threshold value,
After the initial cleanout operation, the chatter value of the insertion torque of the servo motor when the first billet is inserted after the initial cleanout operation is used as the second operation reference value, and the set multiple of the second operation reference value is the chatter threshold value. As
When the insertion torque of the servo motor exceeded the chatter threshold, it was decided to perform a cleanout.

  The set multiple of the second operation reference value is 1.5 times.

  When at least one of the peak value of the insertion torque of the servo motor or the chatter value exceeds a threshold value, an alarm is displayed.

  According to the present invention, it is possible to automatically determine the adhesion state of the aluminum scum in the container and automatically determine the timing of the cleanout operation, eliminate the billet insertion failure, etc., and improve productivity and stabilize quality. become.

FIG. 1 is a plan view of an overall overview of an extrusion press according to the present invention. FIG. 2 is a view when the inserter inserts the billet into the container according to the present invention. FIG. 3 is a diagram of the measurement system of the present invention. Fig. 4 shows (1) waveform of peak value of insertion torque after cleanout. (2) waveform of peak value of insertion torque that requires cleanout. FIG. 5 shows (1) the waveform of the chatter value of the insertion torque after cleanout, and (2) the waveform of the chatter value of the insertion torque that requires cleanout.

  An embodiment of an extrusion press cleanout control method according to the present invention will be described below in detail with reference to the drawings.

  An extrusion press used in the present invention is shown in FIG. The end platen 1 and the main cylinder 2 are arranged to face each other, and both are connected by a plurality of tie rods 3. A container 5 is disposed on the inner side surface of the end platen 1 with a die 4 formed with an extrusion hole interposed therebetween. A billet 6 is loaded into the container 5 and is extruded and pressed toward the die 4 to form a die hole. An extruded product with a corresponding cross section is extruded.

  The main cylinder 2 that generates the pushing action force has a built-in main ram 9 that can be pressurized and moved toward the container 5. At the front end of the main ram 9, a push dummy block (not shown) is brought into close contact with the tip of the extrusion stem 7 so as to be concentrically arranged with the billet loading hole of the container 5, and the main cross is projected toward the container 5. It is attached via the head 8. Therefore, when the main cylinder 2 is driven and the main cross head 8 is advanced, the extrusion stem is inserted into the billet loading hole of the container 5 and the rear end face of the loaded billet 6 is pressurized to extrude the extruded product. .

  FIG. 2 shows an inserter 31 for inserting the die 4, container 5, and billet 6 of the extrusion press into the container 5.

  The inserter 31 includes a pushing part 33 driven by a chain 32, and the billet 6 is pushed by the pushing part 33 and inserted into the container 5. The chain 32 is driven by a servo motor 41. At this time, the billet 6 is pushed by the push-in component 33 and is inserted into the container 5 while rolling on the carry-in roller 34. The servo motor 41 outputs the force for driving the chain 32 at this time as the insertion torque.

FIG. 3 shows the control system of the present invention. The set value of the insertion torque is output from the PLC to the servo drive. This value is, for example, 150%. This value limits so that an insertion torque of 150% or more does not occur. That is, when an insertion torque of 150% or more is generated, the billet 6 cannot be pushed.
This is because if the billet 6 is pushed with a large force without limiting the insertion torque, a donut phenomenon is caused if there is any abnormality in the billet 6.

  The positioning set value is output from the PLC to the servo drive. This is a command for starting insertion of the billet 6 into the container 5 and a position where the billet 6 is completely inserted into the container, that is, a forward limit of the inserter 31.

  An insertion torque detection signal is output from the servo drive to the PLC. The servo drive detects the insertion torque value of the servo motor 41 and sends it to the PLC. Detection is possible from 0% to 300%.

  The monitor can see the waveform of the insertion torque of the servo motor 41. Further, when the insertion torque limit value is exceeded, an alarm can be issued to instruct cleanout.

  The aluminum on the surface of the billet 6 is scraped off and adhered to the inner surface of the container 5 by the frictional force between the inner surface of the container 5 and the high temperature billet 6 during extrusion. As the billet 6 is replaced many times and the extrusion is repeated, aluminum gradually accumulates on the inner surface of the container 5, and a new billet 6 cannot be inserted.

  The clean-out operation is an operation for removing the aluminum deposit on the inner surface of the container 5 described above. Using a disk-like disk having a diameter of about 0.15 mm smaller than the inner diameter of the container 5, this is put in the container 5, and the disk is pushed by the extrusion stem 7 to scrape the aluminum deposit on the inner surface of the container 5. I will take it.

  The torque of the inserter 31 is limited to 150%, and when a torque larger than 150% is applied (when the friction increases), the inserter 31 stops moving, the billet 6 does not enter, and the billet is clogged (insertion failure).

FIG. 4 (1) shows the waveform of the insertion torque having a peak value as a threshold value. The phrase “the peak value is set as a threshold value” means that the highest value (peak value) in the waveform of the insertion torque is set as the threshold value.

  The initial value set in the initial clean-out operation as the peak value threshold is the threshold value set in advance (torque 100% in the present invention) when the clean-out has not been performed yet. It is to be. The first operation means the first cleanout.

  In addition, after the first cleanout operation, the peak value of the insertion torque of the servo motor 41 when the first billet 6 is inserted in the first cleanout operation is the first operation reference value. It is a waveform of the insertion torque of the servo motor 41 when the billet 6 is inserted into the container 5. The peak value of torque at this time is about 50%. This 50% is called the first operation standard.

FIG. 4B is a waveform of the insertion torque value of the servo motor 41 when clean out is necessary. The peak value at this time is about 100% in torque. Twice the insertion torque after cleanout.
That is, the first operation standard is 50% and the set magnification of the first operation standard is twice.
The clean-out is performed after the peak value of the insertion torque exceeds 100%.
Further, the time during which the peak value of 100% is maintained is 0.5 s or longer.

In the case of the present invention, this 100% value is an initial value that becomes a preset threshold value for the initial operation. (The first operation is a first operation in which extrusion is performed from a state where extrusion has not been performed once.) That is, when the value of the insertion torque exceeds 100%, cleanout is performed.
Also, since the peak value of the insertion torque after the initial operation is 50%, this 50% becomes the first operation reference value, which is a set multiple of this operation reference value, which is twice here, that is, 100%. If it exceeds, cleanout will be performed.

FIG. 5B is a waveform of chattering of the insertion torque of the servo motor 41 when cleanout is necessary. This chatter is measured when the billet 6 passes through the surface on which the aluminum on the inner surface of the container 5 is irregularly attached. The chatter value after cleanout is approximately 20% in terms of insertion torque. This 20% chatter value is referred to as a second operation reference value. The chatter value of the insertion torque that needs to be cleaned out is about 30% (the setting magnification is 1.5 times).
The torque waveform immediately after the previous cleanout operation is recorded, and when the torque chatter exceeds 1.5 times, the cleanout operation is performed.

  In the case of the present invention, the insertion torque value of the initial value of chatter, which is a preset threshold value before the first operation, is about 30%. Since the second operation reference value of chatter after the initial operation is about 20%, if the chatter value exceeds about 30%, which is 1.5 times the setting magnification of this second operation reference value, clean out is performed. become.

  FIG. 5A shows a chatter waveform after cleanout (after the first operation).

  In addition, the torque of the inserter 31 is limited to 150%, and if a torque larger than 150% is applied (if the friction increases), the inserter 31 stops moving, the billet 6 does not enter, and the billet 6 is clogged (insertion failure). Become. Therefore, the cleanout operation is performed even when a set value (about 100% is detected for 0.5 s or more) is detected.

  The comparison and determination of the above waveforms are performed by the PLC.

If the billet 6 insertion torque is not improved even after the clean-out operation, or if the billet 6 insertion failure occurs, there is a possibility of misalignment or loosening of the chain 32, so an alarm for core measurement is displayed to prompt maintenance.
Abnormalities are displayed by patterning and comparing waveforms in advance.

Since this invention is the above structure, the following effects are acquired.
According to the present invention, it is possible to automatically determine the adhesion state of the aluminum scum in the container and automatically determine the timing of the cleanout operation, eliminate the billet insertion failure, etc., and improve productivity and stabilize quality. become.

DESCRIPTION OF SYMBOLS 1 End platen 2 Main cylinder 3 Tie rod 4 Dies 5 Container 6 Billet 7 Extrusion stem 8 Main crosshead 9 Main ram 10 Side cylinder 31 Inserter 32 Chain 33 Push-in part 34 Carry-in roller 41 Servo motor

Claims (6)

In a cleanout control method in an extrusion press equipped with a servo motor that drives an inserter for inserting a billet into a container, at least the peak value of the insertion torque of the servo motor or the chatter value when the billet is inserted into the container with an inserter Detect one,
A cleanout control method for an extrusion press, characterized in that cleanout is performed when at least one of a peak value of insertion torque or a chatter value exceeds a threshold value.
The initial operation of the cleanout uses a preset initial value as a peak value threshold,
After the initial cleanout operation, the peak value of the insertion torque of the servo motor when the first billet is inserted after the initial cleanout operation is taken as the first operation reference value, and the set multiple of the first operation reference value is the peak value threshold. As
The cleanout control method for an extrusion press according to claim 1, wherein the cleanout is performed when the insertion torque of the servo motor exceeds a threshold value of a peak value.
3. The extrusion press cleanout control method according to claim 2, wherein a set multiple of the first operation reference value is double.
In the initial operation of the cleanout, an initial value set in advance is used as a chatter threshold value,
After the initial cleanout operation, the chatter value of the insertion torque of the servo motor when the first billet is inserted after the initial cleanout operation is used as the second operation reference value, and the set multiple of the second operation reference value is the chatter threshold value. As
The cleanout control method for an extrusion press according to any one of claims 1 to 3, wherein the cleanout is performed when the insertion torque of the servo motor exceeds a chatter value threshold value.
5. The extrusion press cleanout control method according to claim 4, wherein the set multiple of the second operation reference value is 1.5 times.
The extrusion press according to any one of claims 1 to 5, wherein an alarm is displayed when at least one of a peak value of an insertion torque of the servo motor or a chatter value exceeds a threshold value. Cleanout control method.

Images