JPH091638A - Method and apparatus for controlling to extrude in extruder - Google Patents

Abstract

PURPOSE: To provide a method and an apparatus for controlling to extrude in an extruder capable of effectively preventing the extrusion shape failure at an initial of the extrusion or a unit weight failure and further reducing a return. CONSTITUTION: A rubber temperature in an extrusion head 3 in a past extrusion stable state, the numbers of revolutions of screws of extruders 1a, 1b, 1c with respect to the temperature and the speed of a take-up conveyor 5 are previously set and stored in the data base 7 of the controls of the extruders 1a, 1b, 1c. When stopping the operations of the extruders 1a, 1b, 1c to next extrusion, rubber stable extrusion temperature corresponding to next extrusion size is drawn from the base 7, input to a calculator 8, the extruder temperature regulating temperature, the atmospheric air temperature of the periphery of the extruder and introduced rubber temperature are measured, input to the calculator 8, and the rubber temperature in an extrusion head immediately before the start of next extruder is input to the calculator to be compared and calculated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an extrusion control method and apparatus in an extruder for extruding rubber materials, synthetic resin materials and the like, and more specifically, to a shortage of weight and shape change of the next extrusion material at the initial stage of extrusion. The present invention relates to an extrusion control method and apparatus for an extruder that effectively prevents the above.

[0002]

2. Description of the Related Art Conventionally, when a rubber-like elastic material such as a rubber material or a synthetic resin material is extrusion-molded, when the extrusion molding per lot is completed, the rubber-like elastic material remains in the head of the extruder. Stop the extruder once. Then, when the extruder is restarted to push out the next size, the extrusion shape defect or unit weight defect occurs due to the influence of the rubber-like elastic material remaining in the head in the initial stage of extrusion, resulting in a large amount of returns. There was a problem that it occurs in.

[0003]

Therefore, in order to prevent defective extrusion shape in the initial stage of extrusion and defective unit weight,
For example, as disclosed in Japanese Patent Application Laid-Open No. 4-16324, a method has been proposed in which the screw rotation speed of the extruder and the speed of the stretch conveyor are controlled with the stop time of the extruder as a parameter.

However, in such a conventional method, paying attention only to the stop time before the start of extrusion, the variation in the weight of the extrusion occurs due to the kind of the rubber material, the feeding temperature and the temperature such as the equilibrium temperature until the stable state. I'm not paying attention to being there. Therefore, there is a problem that it is not possible to cope with the variation in rubber weight caused by a slight difference in the stable state due to factors such as seasonal variation and variation in lots of rubber materials.

The present invention has been devised in view of the above-mentioned conventional problems. From the extruder temperature control temperature, the ambient temperature around the extruder, the input rubber temperature or past data,
While the extruder is not operating, the rubber temperature at the next extrusion size when the extrusion is stable is drawn out to the arithmetic unit, and the data input to this arithmetic unit is compared with the rubber temperature in the head just before the extruder starts. However, by controlling the screw rotation speed and the feeding speed of the take-up conveyor, it is possible to effectively prevent the extrusion shape defect in the initial stage of extrusion and the unit weight defect, and to further reduce the return, and the extrusion control method in the extruder. The purpose is to provide the device.

Another object of the present invention is to store in advance a stable temperature of the rubber being extruded and a rubber temperature rise rate per unit time for each type of rubber in a database, and to extrude just before the extrusion. Measure the rubber temperature in the machine head,
By comparing and calculating the rubber temperature in the extruder head and the stable temperature, the temperature difference and time until reaching the equilibrium temperature is obtained, and based on this time, by controlling the screw rotation speed of the extruder, It is an object of the present invention to provide an extrusion control method and apparatus for an extruder, which can eliminate excessive rotation speed control and insufficient rotation speed control even when the type of rubber is different, and can always perform stable extrusion control. It is a thing.

[0007]

In order to achieve the above object, the present invention provides a measuring means for measuring an extruder temperature control temperature,
An extruder equipped with a measuring means for measuring the rubber temperature in the extrusion head, a measuring means for measuring the input rubber temperature, a measuring means for measuring the ambient temperature around the extruder, and an extrusion head in a past stable extrusion state. The rubber temperature inside,
A database that presets and accumulates the screw rotation speed of the extruder and the speed of the take-up conveyor with respect to this rubber temperature, the temperature control temperature of the extruder, the rubber temperature inside the extruder head, the ambient temperature around the extruder, and the past extrusion stability. It is composed of an arithmetic device for performing a comparative arithmetic operation with the rubber temperature in the extrusion head in a state, and the gist is that the arithmetic device is connected to the screw rotation drive motor of the extruder and the drive motor of the take-up conveyor. .

[0008]

The present invention is configured as described above, and the rubber temperature in the extrusion head in the past stable extrusion state and the screw rotation speed and the pulling speed of the extruder with respect to this rubber temperature are stored in the database of the extruder control device. The speed of the take-up conveyor is set in advance, and when the operation of the extruder until the next extrusion is stopped, the rubber stable extrusion temperature corresponding to the next extrusion size is retrieved from the database and input to the arithmetic unit, and the extruder temperature control temperature and The ambient temperature around the extruder and the temperature of the input rubber are measured and input to the arithmetic unit, and the rubber temperature inside the extrusion head immediately before the start of the next extruder is input to the arithmetic unit for comparison calculation. Based on the calculated temperature difference, the screw speed of the extruder and the speed of the take-up conveyor are controlled by the command from the arithmetic unit. Rukoto, the extrusion shape defects and extrusion early, preventing unit weight defects effectively, those which can further reduce the return.

Further, the temperature in the past stable state of rubber during extrusion and the rate of rise in rubber temperature per unit time are inputted in advance into the database of the control device of the extruder for each type of rubber, and then The temperature in the stable state of the rubber corresponding to the type of rubber to be extruded and the rubber temperature rise rate per unit time are extracted and input to the arithmetic unit, and the rubber temperature in the extruder head immediately before the next extrusion is measured. Then, the temperature is input to an arithmetic unit, and the arithmetic unit calculates the temperature difference between the temperature in the stable state of the rubber and the rubber temperature in the extruder head immediately before extrusion, and the rubber temperature increase rate per unit time. The time required to reach a certain temperature is calculated, and the screw speed of the extruder is controlled based on this time. There is no rotational speed control of, is always capable of performing stable extrusion control.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram of an extrusion control device in an extruder for carrying out the extrusion control method according to the present invention, in which the three extruders 1a, 1
Measuring means 2a, 2b, 2c for measuring the temperature controlled by the extruder are attached inside b, 1c, and measuring means 4 for measuring the rubber temperature inside the extrusion head 3 is attached inside the extrusion head 3. Has been.

Drive motors M ₁ , M ₂ and M ₃ for rotating and driving the extrusion screws are connected to the _three extruders 1a, 1b and 1c, respectively. The drive motor M rotates in front of the extrusion head 3. The driven take-up conveyor 5 is installed horizontally. Outside the extrusion head 3, a measuring means 6 for measuring the ambient temperature around the extruder.
Is installed, and a database 7 for presetting and accumulating the rubber temperature in the extrusion head in the past stable extrusion state, the screw rotation speed of the extruders 1a, 1b, 1c and the speed of the take-up conveyor 5 with respect to this rubber temperature. And extruder temperature control, rubber temperature in the extrusion head,
An extrusion controller including an arithmetic unit 8 for comparing and calculating the ambient temperature around the extruder and the rubber temperature in the extrusion head in the past stable extrusion state is installed.

The arithmetic unit 8 includes extruders 1a, 1b,
The rotation drive motors M ₁ , M ₂ and M _{3 of} 1c and the drive motor M of the take-up conveyor 5 are connected, and the screw rotation speed and take-up of the extruders 1a, 1b, 1c are instructed by the arithmetic unit 8. It is arranged to control the speed of the conveyor 5. The present invention is configured as described above,
When performing initial stability control of extrusion by the temperature of rubber in the extrusion head 3, the following method is used.

That is, in the database 7 of the control device of the extruders 1a, 1b, 1c, the rubber temperature in the extrusion head 3 in the past stable extrusion state and the screw rotation speed of the extruders 1a, 1b, 1c with respect to this rubber temperature are stored. And the speed of the take-up conveyor 5 is set and accumulated in advance.
When the operation of the extruders 1a, 1b, 1c until the next extrusion is stopped, the rubber stable extrusion temperature corresponding to the next extrusion size is retrieved from the database 7 and input to the arithmetic unit 8, and the extruder temperature control temperature and the extruder The ambient atmospheric temperature and the input rubber temperature are measured and input to the arithmetic unit 8, and the rubber temperature in the extrusion head immediately before the start of the next extruder is input to the arithmetic unit for comparison calculation.

Based on the temperature difference compared and calculated by the arithmetic unit 8, the screw speeds of the extruders 1a, 1b and 1c and the speed of the take-up conveyor are controlled by a command from the arithmetic unit 8. It is possible to effectively prevent a defective extrusion shape in the initial stage of extrusion and a defective unit weight, and further reduce the return. This extrusion control method will be described more specifically with reference to the timing charts shown in FIGS. 2 and 3. When the horizontal axis indicates the flow direction of time and the extrusion work of the A size material is completed, the extruder is operated. It is stopped once, and during the stop time, it is replaced with an extrusion head corresponding to the next size B extrusion material.

During the stop time of the extruder, the temperature of the extruded material remaining in the extrusion die is reduced by ΔT from the temperature T in the stable extrusion state to T _{1 as} the temperature of the extrusion head decreases, and The weight of the extruded material is also A less than the target weight. In this way, when the temperature of the extrusion head is lower than the temperature T in the stable state during the stop time of the extruder, the extruders 1a, 1b,
The extruder temperature control temperature measured by the measuring means 2a, 2b, 2c provided inside 1c, and the atmospheric temperature from the measuring means 6 for measuring the ambient temperature around the extruder and the input rubber temperature are output to the arithmetic unit 8. In addition, data corresponding to the next size B extruded material selected from the database 7 in which the past data is input in advance is output to the arithmetic unit 8.

Then, the rubber temperature in the extrusion head 3 immediately before the extrusion material of the next size B is extruded is measured by the measuring means 4 and output to the arithmetic unit 8. Then, in the present invention, the data selected from the database 7 and the respective input temperatures are compared and calculated, and the extruder 1a,
By controlling the screw rotation speed of 1b and 1c and the speed of the take-up conveyor, the extrusion shape in the initial stage of extrusion and the unit weight defect are completed in a short time, and the next size B
The stable extruded state of the extruded material, that is, the temperature and weight of the extruded rubber are controlled to be stable.

As a result, the return of the extruded material can be reduced. That is, as shown in FIG. 3, the extruded material extruded from the extruding head 3 is taken by the take-up conveyor 5, conveyed through the running scale 9 and the conveyer conveyor 10 to the position of the weighing scale 11, and then the weight of the extruded material is taken. Is to measure. Next, FIGS. 4 and 5 show another embodiment of the extrusion control method. In this embodiment, as shown in FIG.
When Y and Z are different, paying attention to the fact that the stable temperature (equilibrium temperature) at the time of extrusion and the temperature rise rate per unit time are different for each type of rubber, and the type of rubber to be extruded X, Y, Z
Each time, the control corresponding to the type of rubber is performed.

That is, the temperature T of the rubber in a stable state during extrusion in the past and the rubber temperature increase rate per unit time are input in advance to the database 7 of the controller of the extruder for each type of rubber. Then, the temperature T in the stable state of the rubber corresponding to the type of rubber to be extruded next and the rubber temperature increase rate per unit time are extracted and input to the arithmetic unit 8, and the extruder head 3 immediately before the next extrusion is also extracted. The rubber temperature T ₁ therein is measured, and the temperature T ₁ is input to the arithmetic unit 8.

In the arithmetic unit 8, the temperature difference ΔT between the temperature T of the rubber in a stable state and the rubber temperature T ₁ in the extruder head immediately before extrusion, and the rate of increase in rubber temperature per unit time are used to obtain a constant temperature. The time required to reach it is calculated and the screw speed of the extruder is controlled based on this time. By performing such control, even if the type of rubber is different, excessive rotation speed control and insufficient rotation speed control are eliminated, and stable extrusion control can always be performed.

[0020]

As described above, according to the present invention, in the database of the extruder control device, the rubber temperature in the extrusion head in the past stable extrusion state, the screw rotation speed of the extruder and the take-up conveyor with respect to this rubber temperature. The speed of is set in advance, and when the operation of the extruder until the next extrusion is stopped, the rubber stable extrusion temperature corresponding to the next extrusion size is drawn from the database and input to the arithmetic unit, and the extruder temperature control temperature and extruder The ambient temperature is measured and input to the arithmetic unit, and the rubber temperature in the extrusion head immediately before the start of the next extruder is input to the arithmetic unit for comparison calculation. Based on the instruction from the arithmetic unit, the screw speed of the extruder and the speed of the take-up conveyor are controlled. Early or extrusion shape defects, and unit weight failure it can effectively prevent the effect that can further reduce the return.

Further, the stable temperature of the rubber being extruded and the rate of rise of the rubber temperature per unit time are accumulated in a database in advance for each type of rubber, and the rubber temperature in the extruder head immediately before extrusion is measured. Then, by comparing and calculating the rubber temperature in the extruder head and the stable temperature,
Obtain the temperature difference and time to reach the equilibrium temperature, and control the screw speed of the extruder based on this time to control excessive rotation speed and insufficient rotation speed even if the rubber type is different. Is eliminated, and there is an effect that stable extrusion control can be always performed.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an extrusion control device in an extruder for carrying out an extrusion control method according to the present invention.

FIG. 2 is a timing chart of the extrusion control method according to the present invention.

FIG. 3 is a timing chart of an extrusion control method according to the present invention.

FIG. 4 is a graph explanatory view showing the relationship between temperature and time with respect to the type of rubber to be extruded.

FIG. 5 is a timing chart showing an embodiment of another extrusion control method of the present invention.

[Explanation of symbols]

1a, 1b, 1c Extruder 2a, 2b, 2c Measuring means 3 Extrusion head 4 Measuring means 5 Take-off conveyor 6 Measuring means 7 Database 8 Computing device M Drive motor M ₁ , M ₂ , M ₃ Rotation drive motor

Claims (3)

[Claims] 1. A database of a control device of an extruder,
The temperature of the rubber in the extrusion head in the past stable state of extrusion, the screw rotation speed of the extruder and the speed of the take-up conveyor with respect to this rubber temperature are set in advance, and when the operation of the extruder until the next extrusion is stopped, the next extrusion is performed. The rubber stable extrusion temperature corresponding to the size is extracted from the database and input to the arithmetic unit, and the extruder temperature control temperature, the ambient temperature around the extruder and the input rubber temperature are measured and input to the arithmetic unit, and the next extrusion is performed. The rubber temperature in the extrusion head immediately before the start of the machine is input to the arithmetic unit for comparison calculation, and based on the temperature difference compared and calculated by this arithmetic unit, the screw rotation speed and the pulling speed of the extruder are set by the instruction from the arithmetic unit. An extrusion control method in an extruder, characterized by controlling the speed of a take-up conveyor. 2. The temperature in a stable state of rubber during extrusion in the past for each type of rubber and the rubber temperature rise rate per unit time are input in advance in the database of the controller of the extruder, and then, The temperature in the stable state of the rubber corresponding to the type of rubber to be extruded and the rubber temperature rise rate per unit time are extracted and input to the arithmetic unit, and the rubber temperature in the extruder head immediately before the next extrusion is measured. Then, the temperature is input to an arithmetic unit, and the arithmetic unit calculates the temperature difference between the temperature in the stable state of the rubber and the rubber temperature in the extruder head immediately before extrusion, and the rubber temperature increase rate per unit time. Calculate the time to reach a certain temperature,
An extrusion control method for an extruder, comprising controlling the screw rotation speed of the extruder based on this time. 3. An extruder equipped with a measuring means for measuring the temperature controlled by the extruder, a measuring means for measuring the rubber temperature in the extrusion head, a measuring means for measuring the ambient temperature around the extruder, and a charging means. Measuring means for measuring the rubber temperature, rubber temperature in the extrusion head in the past stable state of extrusion, database for presetting and accumulating the screw rotation speed of the extruder and the speed of the take-up conveyor for this rubber temperature, and the extruder temperature The temperature control unit, the rubber temperature in the extruder head, the ambient temperature around the extruder, and the arithmetic unit for performing arithmetic operations on the rubber temperature in the extrusion head in the past stable extrusion state, and the arithmetic unit and the screw of the extruder. An extrusion control device in an extruder, wherein a rotary drive motor and a drive motor of a take-up conveyor are connected.