JP2001030338A - Extrusion molding equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the fluctuations in the resin pressure at the inlet of a die even during the backwashing of a screen to prevent the lowering of the yield of a product. SOLUTION: In this extrusion molding equipment, a raw material feeder 2, a screw extruder 1, a screen replacing unit 4 fitted with backwashing function capable of backwashing a part of a plurality of screens 1, a gear pump 5 and a molding die 6 are arranged in this order from an upstream side and a gear pump inlet pressure gauge 12 for detecting resin pressure is arranged between the screen replacing unit 4 and the gear pump 5. The fluctuations of the pressure of a resin generated during backwashing are detected by the gear pump inlet pressure gauge 12 and an extrusion control device 21 having a pressure control part 23 for controlling the number of rotations of the screw 1c of the extruder 1 on the basis of the detection signal of the pressure gauge 12 is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an extrusion molding equipment for heating and melting a thermoplastic resin material, kneading the mixture, and extruding with a die.

[0002]

2. Description of the Related Art Conventionally, an extrusion molding apparatus for heating and melting a resin raw material by a screw type extruder, kneading by the shearing energy of the screw, supplying the kneaded mixture to an extrusion die via a gear pump, and molding a product such as a film. Then
A screen unit is interposed between the gear pump and the die in order to remove dirt, foreign matter, degraded substances and impurities contained in the resin raw material.

If dust or foreign matter accumulates on the screen, a predetermined molding pressure cannot be obtained. Therefore, it is necessary to interrupt molding and replace the screen. In particular, when a recycled raw material having a large amount of dust and foreign matter is used as the resin raw material, the frequency of screen clogging increases. This screen is composed of a breaker plate having a large number of through-holes and a mesh screen arranged on the front surface of the breaker plate, and by flowing resin in the opposite direction, that is, by flowing the resin from the breaker plate to the mesh screen. In addition, clogged foreign substances formed on the mesh screen can be removed. For this reason, a screen exchange unit equipped with a backwash mechanism that arranges a screen in each of a plurality of resin flow paths of the screen unit and switches the flow paths to change the direction of the resin flowing into the screen in the opposite direction and backwash the screen. However, for example, Japanese Patent Application Laid-open No. Hei 9-22
No. 5993, for example. By providing the screen exchange unit with the backwashing mechanism, resin molding can be performed continuously without interruption even during backwashing of the screen.

[0004]

However, when the screen exchange unit with the backwash mechanism is provided, when the screen is backwashed, the pressure at the screen exchange unit outlet fluctuates and the accuracy of the product formed by the die is reduced. Drop,
There has been a problem that the yield of products has deteriorated. The present invention has been made to solve the above problems, and to provide an extrusion molding equipment capable of suppressing a change in resin pressure at a die entrance and preventing a decrease in product yield even during backwashing of a screen in a screen exchange unit. With the goal.

[0005]

According to a first aspect of the present invention, a screw-type raw material supply feeder, a screw-type extruder, and a part of a plurality of screens are reversed in order from the upstream side. A screen exchange unit with a backwash function capable of washing, a gear pump, and a molding die are arranged, and a gear pump inlet pressure gauge for detecting resin pressure is arranged between the screen exchange unit and the gear pump. And a pressure control unit for controlling the rotation speed of the screw of the screw-type extruder based on the detection signal.

According to the above construction, the pressure fluctuation generated during the screen backwashing of the screen changing unit is detected by the gear pump inlet pressure gauge, and the pressure control unit controls the rotation speed of the screw of the extruder so that the pressure fluctuation is reduced. By controlling, pressure fluctuation at the inlet of the gear pump is suppressed, pressure fluctuation is further reduced by the gear pump, pressure fluctuation at the outlet (die inlet) is extremely reduced, and the precision of the product formed by the die is kept high. Can be. Therefore, even when a recycled resin raw material containing many foreign substances and impurities is used, the screen can be backwashed without lowering the product yield during operation, and continuous operation can be realized.

According to a second aspect of the present invention, the pressure control section is configured to delay the backwashing start time by a predetermined time and increase the rotation speed of the screw of the screw type extruder in advance. is there. According to the above configuration,
It is possible to reduce the decrease width of the peak pressure value that instantaneously decreases at the start of backwashing, and it is possible to suppress the pressure fluctuation accompanying backwashing.

Further, the invention according to claim 3 is characterized in that the pressure control unit having the above structure is configured to increase the rotation speed of the screw of the screw-type extruder before a predetermined time before the end of the backwashing. It is. According to the above configuration, the pressure at the gear pump inlet can be quickly returned to the steady pressure after the backwashing is completed.

Further, according to the present invention, the resin material is forcibly supplied to the extruder from the material supply feeder, and the number of rotations of the screw of the screw type extruder is provided to the extrusion control device. A feeder control unit for controlling the number of rotations of the screw of the raw material supply feeder based on the above, and the feeder control unit is configured to increase the number of rotations of the screw of the raw material supply feeder a predetermined time before the start of the backwashing. It is.

According to the above configuration, the extruder and the raw material supply feeder are linked, and the amount of raw material supplied from the raw material supply feeder is increased before the start of the backwash, so that the pressure drop at the start of the backwash is reduced. Can be effectively suppressed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Here, an embodiment of the extrusion molding equipment according to the present invention will be described with reference to FIGS. FIG.
As shown in FIG. 1, reference numeral 1 denotes a single-screw or double-screw extruder.
Is heated and melted by a heating device (not shown) by a heating device (not shown), and the kneading screw 1c is rotationally driven by a screw driving device (electric motor) 3 to perform kneading. In addition, the raw material supply feeder 2 may replenish the raw material to the raw material hopper 1b, and the extruder (usually a single-screw type) 1 may receive a fixed amount according to the rotation speed of the screw 1c, or as shown by a virtual line. Alternatively, a raw material quantitative supply type in which the resin raw material fed from the raw material supply feeder 2 is entirely received by the extruder (such as a twin screw type) 1 may be used.

At the resin outlet side of the extruder 1, a screen exchange unit 4 having a plurality of screens, a gear pump 5 for maintaining a constant resin pressure and reducing pressure fluctuations, and an extrusion die 6 are provided. Have been. A unit inlet pressure gauge 11 for measuring a resin pressure is provided in a screen inlet conduit 7 connecting the extruder 1 and the screen changing unit 4.
A gear pump inlet pressure gauge 12 for measuring resin pressure is provided on a gear pump inlet conduit 8 connecting the gear pump 5 and the gear pump 5, and a die inlet pressure gauge 13 for measuring resin pressure on a die inlet conduit 9 connecting the gear pump 5 and the die 6. Are arranged.

The extrusion control device 21 for controlling the extrusion molding equipment operates the screen exchange unit 4 when the unit entrance pressure gauge 11 detects that the resin pressure at the entrance of the screen exchange unit 4 has exceeded a certain value. When the pressure change of the resin discharged from the screen exchange unit 4 is detected by the screen changer control unit 22 that outputs a signal to start the backwashing and the gear pump inlet pressure gauge 12, the screw driving device 3 transmits the screw rotation speed. A pressure control unit 23 that outputs a control signal; a molding pressure control unit 24 that controls the rotation speed of the gear pump 5 based on the pressure of resin flowing into the die 6 from the gear pump 5 detected by the die inlet pressure gauge 13; The screw of the raw material supply feeder 2 is controlled based on the signal of the rotation detector 14 of the kneading screw 1c in the driving device 3. A feeder control unit 25 for controlling the controlled material supply amount the number of revolutions of the screw 2b outputs a control signal to the driving unit 2a. The feeder control unit 25 is applied to a twin-screw extruder or the like provided with a feeder of a constant material supply type, and the kneading screw 1 is provided.
c of the raw material supply feeder 2 based on the number of rotations of
The number of rotations of b is controlled.

In the above extrusion molding equipment, when the resin temperature is constant (the temperature change is small), the gear pump 5
Fluctuation value of inlet pressure ΔP (detected pressure value-steady pressure value)
And the extruding amount Q of the extruder 1 are in a proportional relationship of ΔP = K × Q, and the extruding amount Q and the rotation speed Ns of the screw 1 c
Is proportional. Therefore, the pressure control unit 23 is configured to perform the proportional-integral control so as to decrease the rotation speed Ns when the fluctuation value ΔP increases and to increase the rotation speed Ns when the fluctuation value ΔP decreases.

As shown in FIG. 2, the screen exchange unit 4 has first and second piston parts 32A, 32 formed in slide holes 31A, 31B formed in the unit body 30.
B are slidably arranged, and the first and second piston portions 32 are switched by switching actuators 33A and 33B.
A and 32B are moved to the first backwash positions Aa and Ba, the non-backwash positions Ab and Bb, and the second backwash positions Ac and Bc, respectively. The first and second piston portions 32A and 32B have 2
Resin inlets 34Aa, 34Ab, 34Ba, 34Bb
Connected to one resin outlet 34Ac, 34Bc
Shaped mixing passages 34A, 34B are formed, and the first and second resin inlets 34Aa, 34Ab, 34Ba, 34Bb each include a breaker plate and a mesh screen on the front surface thereof.
Second screens 35Aa and 35Ab and third and fourth screens 35Ba and 35Bb are provided, respectively.

As shown in FIG. 2, when the first and second piston portions 32A, 32B are in the non-backwash positions Ab, Bb, four inflow passages 36Aa, 36Ab, 36Ba and 36Bb are resin inlets 34Aa and 34A of the mixing passages 34A and 34B, respectively.
b, 34Ba, 34Bb, and a resin outlet 3
4Ac and 34Bc are connected to the gear pump inlet conduit 8 via the discharge passages 37A and 37B and the merge passage 38.

In order to discharge the contaminated resin after back washing,
When the first piston portion 32A is switched to the first backwash position Aa, a first waste passage 39Aa is formed to communicate with the first screen 35Aa via the resin inlet 34Aa. When the second piston portion 32B is switched to the first backwash position Ba, a third waste passage 39Ba is formed to communicate with the third screen 35Ba via the resin inlet 34Ba. Further, when the first piston portion 32A is switched to the second backwash position Ac, the second screen 35A
b is formed with a second waste passage 39Ab communicating with the resin inlet 34Ab. Second backwash position B
When the second piston portion 32B is switched to the position c, a fourth waste passage 39Bb is formed to communicate with the fourth screen 35Bb via the resin inlet 34Bb.

Therefore, at the non-backwash positions Ab and Bb,
The resin is sent from the inflow passages 36Aa, 36Ab, 36Ba, 36Bb to the resin inlets 34Aa, 34Ab, 34Ba, 34Bb and the first to fourth screens 35Aa to 35Bb.
Respectively to remove dust, foreign matter, degraded substances and impurities. And the resin outlets 34Ac, 34Bc
From the gear pump inlet conduit 8 through the discharge passages 37A and 37B and the merge passage 38.

The first and second piston parts 32A, 32B
Is slid to the first backwash position Aa, Ba, as shown in FIG. 3, the resin is sent from the inflow passages 36Ab, 36Bb to the resin inlets 34Ab, 34Bb, and the second and fourth screens 35Ab, 35Bb cause dust. And foreign substances, degraded substances and impurities are removed. And part of the resin is the first, third
The screens 35 </ b> Aa and 35 </ b> Ba are back-flowed to remove clogged foreign substances and the like, and are brought into contact therewith.
a and 39Ba are discharged outside. The remaining resin is extruded from the resin outlets 34Ac and 34Bc to the gear pump inlet conduit 8 via the merging passage 38.

Further, the first and second piston portions 32A, 3
When 2B is slid to the second backwashing positions Ac and Bc, as shown in FIG. 4, the resin is sent from the inflow passages 36Aa and 36Ba to the resin inlets 34Aa and 34Ba, and is sent to the first and third screens 35Aa and 35Ba. Dirt, foreign matter, degraded substances and impurities are removed. Then, a part of the resin flows backward through the second and fourth screens 35Ab and 35Bb to remove clogged foreign substances and the like, and is discharged to the outside from the second and fourth waste passages 39Ab and 39Bb. The remaining resin flows from the resin outlets 34Ac and 34Bc to the merging passage 38.
Through the gear pump inlet conduit 8.

In the above description of the operation, two screens are simultaneously backwashed. However, in practice, each screen is implemented one by one in order to reduce pressure fluctuation. Example 1 (FIG. 5): Conventional example Single screw extruder [screw diameter 100 mm, casing temperature 2]
50-280 ° C., screw rotation speed 116 rpm (constant)], gear pump (temperature 280 ° C., rotation speed 18 rpm)
m), a die for pellet molding (temperature: 250 ° C., extrusion rate: 29
0 kg / H) in the same manner as in the above embodiment. Then, using a pulverized A-PET sheet as a raw material, the casing 1a
Was vented and suction-extruded at one point in the middle of the sample.
During the molding, backwashing of the first to fourth screens 35Aa to 35Bb was sequentially performed. Here, the pressure control unit 23 is not controlled.

When the first piston 32A is slid to the first backwash position Aa to start the backwash of the first screen 35Aa, the pressure value b at the inlet of the gear pump 5 becomes about 5 before the backwash.
Although a steady pressure of 5 kg / cm ² was maintained, the pressure instantaneously decreased to about 20 kg / cm ² , and gradually decreased during back washing. Next, when the first piston 32A is slid to the second backwash position Ac to switch to the cleaning of the second screen 35Ab, the flow path on the first piston portion 32A side is instantaneously completely closed, and the pressure value is temporarily reduced. b rapidly rises to near the steady pressure, but when the flow path is connected, the resin pressure b at the inlet of the gear pump decreases again, and gradually decreases until the next backwash. Thus, the screen 35A
a to 35Bb, the pressure value b decreases sequentially,
When the screen 35Bb is backwashed, the pressure value b is about 10 k.
g / cm ² . For this reason, it takes time to return to the steady pressure even after the backwashing is completed.

According to the above conventional results, a remarkable decrease in the resin pressure b at the inlet of the gear pump 5 at the time of backwashing was observed, and it also took time to return to a steady pressure after the backwashing. As a result, it was recognized that the pressure fluctuation c at the entrance of the die 6 also became large, and it was impossible to continue the stable operation, and that the product accuracy was lowered and the yield was deteriorated.

Embodiment 2 (FIG. 6) From Embodiment 1 above. At the start of backwashing, the inlet resin pressure b of the gear pump 5 changes instantaneously and abruptly from the steady pressure. Since the deviation change rate is large as described above, the hunting phenomenon is likely to occur when the differential control is strongly applied to the control symmetry. .
Proportional control, which performs control in proportion to the deviation, is effective, but it is necessary to set a value that is neither excessive nor insufficient. . In order to prevent a gradual pressure drop during backwashing excluding the peak pressure, it is effective to perform a correction control and add a corrected output toward the deviation 0 while there is a deviation. However, overshoot is likely to occur when the integration time is shortened and the output for correcting the deviation due to the integration operation is increased. It is possible that.

Therefore, in the second embodiment, the PI control is performed in the pressure control unit 23 based on the above analysis results. Here, the reference pressure at the inlet of the gear pump 5 is 50 kg / cm ²
The feeder control by the feeder control unit 25 is not performed. The P operation output is weakened to 100%, and the I operation is slowed down to 30 seconds to weaken both PI operations. And
The four screens 35Aa to 35Bb are sequentially washed, and this is repeated twice.

According to the second embodiment, as shown in FIG. 6, when the backwashing of the screen 35Aa is started, the fluctuation of the pressure value b at the inlet of the gear pump 5 is not changed by the PI operation control. It is smaller than during control. However, the fluctuation of the pressure value b at the time of the subsequent screen switching becomes larger than that at the time of non-control, and it is understood that the P operation control is working too strongly. In addition, the pressure value b during the backwashing is observed during the first backwashing of the screens 35Aa and 35Ab, and is generally higher than when the screen is not controlled.
This is because the operation control was strongly exhibited. Further, the pressure value b during the backwashing is about 40 kg / cm ² without lowering as a whole.
It becomes clear that the effect of the I operation control appears. Further, the pressure value b after the cleaning of the last screen 35Bb quickly returns to the steady pressure from the high pressure peak value.

Therefore, according to the second embodiment, by selecting an appropriate control constant by the proportional control and the integral control without performing the differential control, the pressure value b can be maintained even during the backwashing of the screen. This suggests the effectiveness of reducing the fluctuation and suppressing the fluctuation of the pressure value c at the outlet of the gear pump 5 (the inlet of the die 6).

Embodiment 3 (FIG. 7) The present invention. Based on Embodiment 2, the control constant is P operation output of 150
%, And the effect of the PI control operation is weakened by setting the I operation to 40 seconds. According to the third embodiment, the pressure value b at the inlet of the gear pump 5 at the start of backwashing and at the time of screen switching is the same as that of the second embodiment.
It is smaller. In addition, during backwashing except for the peak pressure of the pressure value b, it shows a slow increasing tendency. As a result, it is understood that the fluctuation of the pressure value c at the outlet (the inlet of the die 6) of the gear pump 5 is suppressed. As a result, it is possible to suppress the fluctuation of the pressure value c at the inlet of the die 6 during the backwashing and to mold the product with high accuracy, thereby enabling a long-term stable operation.

Example 4 (FIG. 8): The present invention A co-rotating twin-screw extruder [screw diameter about 100 mm,
Casing temperature 270 to 290 ° C], screen exchange unit [unit main body temperature 265 ° C, screen mesh set of 3 (max. # 600)] Gear pump (temperature 260
° C, rotation number 14 rpm), and a die for forming an A-PET thin sheet (temperature: 260 ° C, extrusion rate: 450 kg / H) were arranged in the same manner as in the above embodiment. Then, a recycled pulverized A-PET resin is used as a raw material, and the intermediate portion 2 of the casing 1a is used.
A vent is suctioned at a location to remove water and volatile components.
-Extrusion of a PET thin film sheet was performed. During the molding, backwashing of the first to fourth screens 35Aa to 35Bb was sequentially performed.

In the pressure controller 23, the PI control is performed with the reference pressure at the inlet of the gear pump 5 set to 15 kg / cm ² , the P operation at 70%, and the I operation at 15 seconds.
Here, the PI value is different from Examples 2 and 3 because the extruder is 2
This is because it is an axial type. Further, the feeder control unit 25 controls the feed of the feed of the feed feeder 2 by proportional control.

According to the fourth embodiment, the fluctuation of the pressure value b at the inlet of the gear pump 5 is further improved as compared with the single-screw extruders of the second and third embodiments. The peak value is small. The pressure value b excluding the peak value is also flat. As a result, the pressure value c of the outlet of the gear pump 5 (the inlet of the die 6) is also substantially constant, and the A-PET thin film sheet can be stably formed by the die 6 even when the backwashing of the screen of the screen changing unit 4 is repeated during operation. Extrusion molding could be performed with high precision. It should be noted that the screw rotation speed a of the extruder 1 is based on the pressure value b according to FIG.
Is controlled.

Further, in the second to fourth embodiments, the backwashing time is delayed by a predetermined time, for example, 5 to 10 seconds by the screen backwashing start signal output from the screen changer control section 22, during which time the amount of extrusion Q / the screw rotation speed is increased. By outputting an operation signal from the pressure control unit 23 to the control unit of the screw driving device 3 so as to increase Ns (specific rotation extrusion amount) in advance, it is possible to prevent a rapid decrease in the pressure value b generated at the time of starting backwashing. We were able to.

At the end of cleaning the last screen 35Bb, for example, 5 to 1 before a predetermined time before the backwashing end time.
0 seconds before, the specific rotation extrusion amount Q / Ns is set to a predetermined amount, for example, 5
By outputting a signal from the pressure control unit 23 to the control unit of the screw driving device 3 so as to decrease the pressure value by 6%, the pressure value b after the backwashing was completed could be quickly returned to the steady pressure.

According to the above-described embodiment, the pressure fluctuation generated when the screens 35Aa to 35Bb of the screen changing unit 4 are backwashed is detected by the gear pump inlet pressure gauge 12,
By controlling the number of rotations of the screw of the extruder 1 by the pressure control unit 23 so as to reduce the pressure fluctuation,
The pressure fluctuation at the inlet of the gear pump 5 is suppressed, and the pressure fluctuation at the outlet (die inlet) of the gear pump 5 is extremely reduced by reducing the pressure fluctuation by the gear pump 5.
Thus, the precision of the product to be molded can be kept high. Therefore, even when a recycled resin raw material having a large amount of foreign substances and impurities is used, the screens 35Aa to 35Bb can be sequentially backwashed without lowering the product yield during operation, and continuous operation can be realized. it can.

The pressure control unit 23 detects the backwashing start time based on the backwashing start signal from the screen changer control unit 22, delays the backwashing start time by a predetermined time, and reduces the rotation speed of the screw 1c of the extruder 1. Since the pressure is increased in advance, it is possible to reduce the decrease width of the peak pressure value that instantaneously decreases at the start of the backwashing, and it is possible to suppress the pressure fluctuation caused by the backwashing. Further, the inlet pressure of the screen exchange unit 4 can be quickly returned to the steady pressure after the backwashing is completed.

Further, when the resin raw material is supplied from the raw material supply feeder 2 to the extruder 1 in a fixed amount, the feeder control unit 25 increases the screw rotation speed of the raw material supply feeder in advance a predetermined time before the backwashing starts. By increasing the raw material supply amount in this way, a pressure drop at the start of backwashing can be effectively suppressed.

[0037]

As described above, according to the first aspect of the present invention, the pressure fluctuation generated during the screen backwashing of the screen changing unit is detected by the gear pump inlet pressure gauge, and the pressure fluctuation is reduced by the pressure control unit. By controlling the rotation speed of the screw of the extruder so that the pressure fluctuation at the inlet of the gear pump is suppressed, the pressure fluctuation is further reduced by the gear pump, and the pressure fluctuation at the outlet (die inlet) is extremely reduced. Thus, the precision of the product to be molded can be kept high. Therefore, even when a recycled resin raw material containing many foreign substances and impurities is used, the screen can be backwashed without lowering the product yield during operation, and continuous operation can be realized.

Further, according to the second aspect of the present invention, it is possible to reduce the width of the peak pressure value which instantaneously decreases at the start of backwashing, and to suppress pressure fluctuations caused by backwashing. Furthermore, according to the third aspect of the present invention, the pressure at the gear pump inlet can be quickly returned to the steady pressure after the backwashing is completed.

According to the fourth aspect of the present invention, the extruder and the raw material supply feeder are interlocked with each other, and the amount of raw material supplied from the raw material supply feeder is increased before the backwash starts, so that the backwashing can be started. The pressure drop at the time can be effectively suppressed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of an extrusion molding facility according to the present invention.

FIG. 2 is a configuration diagram showing a screen exchange unit of the extrusion molding equipment.

FIG. 3 is a configuration diagram showing a backwash state of a screen of the screen exchange unit.

FIG. 4 is a configuration diagram showing a backwash state of another screen of the screen exchange unit.

FIG. 5 is a graph showing a screw rotation speed and a resin pressure in a backwashing state in a non-controlled state in Example 1 of the extrusion molding equipment.

FIG. 6 is a graph showing a screw rotation speed and a resin pressure in a backwashing state during PI control in Example 2 of the extrusion molding equipment.

FIG. 7 is a graph showing a screw rotation speed and a resin pressure in a backwashing state during PI control in Example 3 of the extrusion molding equipment.

FIG. 8 is a graph showing the screw rotation speed and the resin pressure in the backwashing state during PI control in Example 4 of the extrusion molding equipment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 extruder 2 raw material supply feeder 3 screw driving device 4 screen exchange unit 5 gear pump 6 die 11 unit inlet pressure gauge 12 gear pump inlet pressure gauge 13 die inlet pressure gauge 21 extrusion control device 22 screen changer control unit 23 pressure control unit 24 molding pressure Control unit 25 Feeder control unit

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Yoshio Furuhashi, Inventor 1-7-89, Minamikohoku, Suminoe-ku, Osaka-shi, Osaka Inside Hitachi Zosen Corporation (72) Inventor Kazuki Okada 1-chome, Minamikohoku, Suminoe-ku, Osaka-shi, Osaka No. 7-89 Hitachi Zosen Corporation (72) Inventor Sakuhiro Sakane 1-7-89 Hitachi Zosen Corporation (72) Inventor Takeshi Kimura Minami Suminoe-ku, Osaka-shi 1-7-89 Kohoku F-term in Hitachi Zosen Corporation (reference) 4F207 AP02 AP03 AR02 AR09 KA01 KF01 KK12 KL39 KL94 KM04 KM05 KM13 KM14

Claims (4)

[Claims] 1. A screw-type raw material supply feeder, a screw-type extruder, and a screen exchange unit with a backwash function capable of backwashing a part of a plurality of screens in order from an upstream side.
A gear pump and a molding die are arranged, and a gear pump inlet pressure gauge for detecting resin pressure is arranged between the front screen exchange unit and the gear unit. Extrusion molding equipment provided with an extrusion control device having a pressure control unit for detecting the number of rotations of a screw of a screw type extruder based on a detection signal detected by a meter. 2. The extrusion molding according to claim 1, wherein the pressure control section delays the backwashing start time by a predetermined time and increases the rotation speed of the screw of the screw type extruder in advance. Facility. 3. The pressure control unit according to claim 1, wherein the pressure control unit is configured to increase the number of rotations of the screw of the screw type extruder before a predetermined time before the end of the backwashing. Extrusion equipment. 4. A method for forcibly supplying a resin raw material from a raw material supply feeder to an extruder, wherein the extrusion control device controls a rotational speed of the screw of the raw material supply feeder based on a rotational speed of the screw of the screw type extruder. 3. The extrusion molding according to claim 2, wherein a feeder control section for controlling the feed rate is provided, and the feeder control section is configured to increase the rotation speed of the screw of the raw material supply feeder a predetermined time before the start of the backwashing. Facility.