JPH07106593B2 - Extrusion die lip adjustment device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an extrusion molding die lip adjusting apparatus that can be used in a non-stretched film or sheet manufacturing apparatus, a stretched film manufacturing apparatus, and the like.

(Prior Art) An example of a conventional extrusion molding die lip adjusting device will be described with reference to FIGS. 3 and 4. First, in FIG. 3, a flexible lip 13 and a fixed lip 14 are formed on the tips of the die body 11 and the die body 12, and a lip gap 15 is formed on the opposing surfaces of the both lips 13, 14. In addition, the lip gap 15 is provided at the tip of the die body 11 and on the protrusion above the flexible lip 13.
A plurality of thermal displacement units 16 installed in the width direction of the die
A heat insulating plate 17 is placed between the two and 11, and one side is fixed by bolts 18, the other side is a free end, and a through hole is provided in the longitudinal direction. 19 is a washer for adjusting the thickness of the heat insulating plate 17. A heater 20 and a thermocouple 21 are inserted into the thermal displacement unit 16, and a die bolt 22 screwed to the upper surface of the flexible lip 13 penetrates the die lip 11 and the die main body 11 with a gap. Is fixed to the thermal displacement unit 16 with a screw 31 and a presser 32.

As shown in FIG. 4, one end (not shown) of the thermal displacement unit 16 is connected to an air source, and the other end (not shown) has a closed air supply pipe 24 inserted therein. A hole 25 is formed at a position facing the die bolt 22 in the hole 24, and the hole 25 communicates with an air supply port 26 connected to a hole for passing the die bolt of the thermal displacement unit 16. On the other hand, the die bolt 22 has a lower part sealed with a seal material 27 and an upper part sealed with a presser 32, and has a horizontal hole 28 and a vertical hole 29 communicating with the horizontal hole 28 at a position facing the air supply port 26. Therefore, the air supplied to the air supply pipe 24 flows into the outer periphery of the die bolt 22 from the hole 25 and the air supply port 26, and then is discharged to the outside through the horizontal hole 28 and the vertical hole 29.

In such a configuration, the thermal displacement unit 16 includes the heater 20
When it is heated by, it expands thermally and expands upward. At this time, the die bolt 22 also receives the heat of the heater 20, but since the outer periphery and the vertical hole 29 inside are cooled by air, the thermal expansion amount is smaller than that of the thermal displacement unit 16, and the upper end is the thermal displacement unit. It is stuck to 16. Therefore die bolt 22
The upper end is lifted by the thermal displacement unit 16, and the flexible lip 13 bends upward with this. That is, the lip gap 15 becomes wider and the flow rate of the molten resin increases. At this time, since the die bolt 22 is air-cooled, the die bolt 22 is slightly heated, and this heat is transferred from the flexible lip 13 to the molten resin inside, and the heat of the thermal displacement unit 16 is transferred to the heat insulating plate 17.
Through the die body 11 to the molten resin to reduce its viscosity and increase the flow rate of the molten resin.

On the other hand, when the power supply to the heater 20 is cut off, the thermal displacement unit 16 contracts and the die bolt 22 also contracts. At this time, die bolt 22
Since it is always cooled, the amount of change in heat (the amount of contraction) is smaller than that of the thermal displacement unit 16, so the flexible lip 13 is pushed by the die bolt 22 and bends downward. Therefore, the flow rate of the molten resin flowing through the lip gap 15 decreases. Meanwhile flexible lip 13
Since the die bolt 22 is not heated, as compared with the time when the thermal displacement unit 16 is heated, the temperature of the molten resin is cooled and the viscosity of the molten resin becomes higher, and the flow rate tends to decrease.

Next, FIG. 5 shows another conventional example.
Reference numeral 15 is the same as the conventional example shown in FIG. The fifth here
Explaining the difference from FIG. 3 in the figure, one side of the plurality of thermal displacement units 51 is screwed and fixed to the die body 11, and the other side is a free end. Further, 52 is a die bolt, one end of which is in contact with the upper surface of the flexible lip 13 and the other end of which is fixed to the free end side of the thermal displacement unit 51 by screwing, and a seal 53 is provided at the lower end of the thermal displacement unit 51. It is airtight. 54 is a heater, which is provided with a thermocouple (not shown). An air supply pipe 56 attached to the die body 11 via a frame 55 is connected by a pipe 57 to an air supply port 58 of the thermal displacement unit 51, and the air supply port 58 communicates with a vertical hole 59 of the die bolt 52. It opens in the hole 60.

(Problems to be Solved by the Invention) In the above-mentioned conventional apparatus, since the die bolt (lip adjusting bolt) is indirectly heated by the thermal displacement unit (heating unit), the response of expansion and contraction of the adjusting bolt is high. Was loose. In addition, a large space is required to install the unit, and in addition, the intervals between the adjusting bolts are increased, which is a drawback. Further, there is a drawback in that the push-pull manual adjustment cannot be performed, or when a push-pull manual adjusting device is provided, a backlash of the screw causes a play when the push-pull is changed to the pull. Further, in the case where the heater is also used for pushing and pulling, if the heater is broken only at one place, the adjusting bolt contracts greatly, and there is a risk of breaking due to excessive force.

The present invention has been proposed to solve the above problems.

(Means for Solving the Problem) For this reason, the present invention is a die lip adjusting device for pushing and pulling a plurality of lips provided in the lip width direction of a molten resin sheet or film extrusion molding die, one end of which is a die lip. Fasten the stud bolt that is fastened to the other end to install a disc spring on the other end, a disc spring inserted under the collar of the stud bolt and the stud bolt to press the disc spring. The screw seat that is fitted and screwed into the die main body, the large diameter adjustment bolt with screws with different pitches on the inner diameter side and the outer diameter side, and the inner diameter side of the large diameter adjustment bolt The adjusting bolt is equipped with a small-diameter adjusting bolt installed so as to abut the end face, and a nut screwed into the outer diameter side screw of the large-diameter adjusting bolt and fixed to the die body via a holding plate. The die is inserted and installed from the upper surface of the die body, and this is used as a means for solving the problem.

(Function) Install the tip of the small diameter adjustment bolt screwed into the inner diameter side of the large diameter adjustment bolt inserted from the top of the die body so that it abuts the upper end surface of the stud bolt, and push the screw seat and the adjustment bolt together. After adjusting the position of the stud bolt so that the die lip clearance is the specified dimension by tightening the screw, tighten the screw seat and set the disc spring in the compressed state by the prescribed amount. So that there is no play due to backlash of the adjusting bolt screw.

(Embodiment) The present invention will be described below with reference to embodiments of the drawings, and FIGS. 1 and 2 show embodiments of the present invention. In Figure 1,
A resin flow path 120 is formed by combining the die body 101 and the die body 102, and the flexible lip at the tip of the die body 101 is formed.
A resin discharge port 121 is formed by 101 ′ and the tip of the die body 102. A holding block 103 for holding the adjustment bolt is fixed to the outside of the die body 101 by a bolt 119.

Further, a stud bolt 105 is screwed into a surface of the tip of the die body 101 opposite to the flow path surface of the flexible lip 101 ′ via a heat insulating material 134 (ceramic screw part or stainless steel helisert), and a lock nut 106 is used. It is fixed via a heat insulating plate 135. At the other end of the stud bolt 105, a flange portion 124 for installing the disc spring 108 is provided, and is installed in a state where it is inserted into a screw hole 125 formed in the holding block 103. A disc spring 108 is inserted into the lower surface of the collar portion 124, and a screw seat 107 is screwed into the screw hole 125 of the holding block 103 in order to apply a spring force to the disc spring 108.

Further, on the outside of the holding block 103, a large-diameter adjustment bolt 110 in which a small-diameter adjustment bolt 109 is screwed into the inner diameter side is provided, and an outer diameter side screw of the same large-diameter adjustment bolt 110 (the inner thread and the pitch are A fixing nut 111 is screwed into a different part), and the fixing nut 111 is fixedly attached to the holding block 103 by a bolt (not shown) via a holding plate 112. The pressing plate 112 is divided so as to press over the two fixing nuts 111. The adjusting bolt 109,110
And the fixing nut 111 are combined, and the small diameter adjusting bolt 109 is provided with a rotation stop pin 113 so that the fixing block 111 does not rotate with respect to the holding block 103, and the fixing nut 111 also does not rotate so that the fixing nut 111 does not rotate. After adjusting the differential screw type adjustment bolt, loosen the screw seat 107 with respect to the holding block 103 and free the disc spring 108, then turn the large diameter adjustment bolt 110 to finely adjust the tip of the small diameter adjustment bolt 109. Then, after finely adjusting the tip position of the stud bolt 105, tighten the screw seat 107 to tighten the disc spring 1
Manual adjustment is performed by applying the required spring force to 08.

On the other hand, the heater 104 for heating the stud bolt 105 is formed in a tubular shape, and has an inner diameter processed so as to fit the outer periphery of the stud bolt 105 and is installed on the outer periphery of the stud bolt 105. In addition, a heat insulating material 118 is provided between the heater 104 and the die body 101 to minimize heat transfer between them. In the figure, reference numeral 117 is a heat insulating plate, which substantially seals the space 123 surrounded by the flexible lip 101 'and the flange portion 122 of the die body 101, and also has a role of heat insulating for preventing heat radiation from the stud bolt 105 and the like. To do.
Further, 114 is an air supply / exhaust jacket, which is provided to provide an air supply passage for cooling the heater 104 for heating the stud bolt 105, and is provided to shield the heater 104 from the outside air so as to cover the entire width of the die. Air is supplied from an air supply port 115 that is provided to uniformly supply air over the entire width, passes through a hole 115-1 that is appropriately opened over the entire width, and passes through a ventilation path 115-2. 3 is supplied to the outer circumference of the heater 104, and the exhaust port 11 is cooled while cooling the heater 104 through the ventilation passage 115-4.
It is designed to be exhausted from 6. By cooling the heater 104 in this way, the stud bolt 105 is also cooled.

Next, the operation of the embodiment configured as described above will be described. In the adjusting bolt device, the stud bolt 105 and the adjusting bolts 109 and 110 are separated, so that the pulling force by the screw cannot be applied. Since the spring 108 is provided to apply a force in the pulling direction, when the adjusting bolts 109 and 110 are turned in the loosening direction, the force of the disc spring 108 causes the stud bolt 1 to move.
The pulling force is applied to 05. The force and adjustment amount of the disc springs 108 can be appropriately adjusted by increasing or decreasing the number of disc springs in parallel and the number of disc springs in series. Therefore, the required number may be selected and installed (two in FIG. 1). Shows the case where two sets of the above are stacked in parallel and combined in series.

In the case of automatic adjustment by heating and cooling the stud bolt 105, when the stud bolt 105 is heated and expanded, the upper end of the stud bolt 105 is pressed by the small diameter adjustment bolt 109, so that the stud bolt 105 does not expand. As it is, the flexible lip 101 'pushes the force. On the other hand, when cooled and contracted, the upper end of the stud bolt 105 moves in the direction away from the adjustment bolt 109, but the force of the disc spring 108 pushes it upward. , A force acts in the direction of pulling the flexible lip 101 ', and it can be used for both pushing and pulling. Since the adjusting bolts 109 and 110 are constantly applied with force by the disc spring 108 in the same direction, there is no screw play at the time of conversion of push and pull.

In addition, stud bolts 105 and adjusting bolts 109,110 using screws
Since the part is separated, even if only one heater is disconnected and the stud bolt 105 shrinks a lot, the disc spring 1
Since it is absorbed by the margin of flexure of 08, a force greater than the reaction force of the disc spring 108 is not applied, and the stud bolt 105 is prevented from being damaged when the heater is disconnected, which is the biggest problem in both push and pull dual use. Can be done. Further, by installing the pressing plate 112 for pressing the fixing nut 111 so as to be divided into two for each nut, the adjusting bolts 109, 110 or the heater 1 can be installed.
If something goes wrong with 04, it will be easy to replace only one of them.

Although the case where the heater 104 is provided has been described above, the apparatus of this embodiment has the heater 104, the heat insulating plate 118, and the air supply / exhaust jacket.
Of course, it is possible to use only the manual gap adjusting device from which 114 is removed.

(Effects of the Invention) As described in detail above, according to the present invention, one end of a stud bolt is fastened to a die lip, and the other end is brought into contact with a small diameter adjustment bolt screwed into the inner diameter side of a large diameter adjustment bolt capable of being pushed and pulled. Since this is done, the fine adjustment of the lip can be performed manually with high accuracy. Also, since the large and small diameter adjustment bolts and the stud bolts are separated, the pulling side force cannot be applied by the screws, but since a disc spring is provided to apply pulling force, turning the adjustment bolts in a loosening direction The force of the disc spring causes the stud bolt to be pulled. Further, since the adjusting bolt is always applied with a force in the same direction by the disc spring, there is no play of the screw at the time of conversion of push and pull.

If the structure is such that the stud bolt is inserted into the heater, the heating time can be shortened, and if the outer circumference of the heater is directly supplied and exhausted to cool, the cooling time can be shortened. Expansion and contraction response of stud bolts,
That is, the response of push-pull adjustment of the flexible lip can be improved.
When the stud bolt is heated and cooled for automatic adjustment, if the stud bolt is heated and expanded, the upper end of the stud bolt is held down by the small diameter adjustment bolt, so the stud bolt's extension directly acts as the force to push the die lip. When cooling and shrinking, the upper end of the stud bolt moves in the direction away from the small diameter adjustment bolt, but since the pressing force is applied upward by the disc spring force, the force acts in the direction to pull the die lip, Dual use is possible. Further, even if only one of the heaters provided is broken and the stud bolt is greatly contracted, it is absorbed by the margin of flexure of the disc spring, so a force greater than the reaction force of the additional spring is not applied. It is possible to prevent the stud bolt from being damaged when the heater is disconnected, which is the biggest problem in both push and pull operation. Further, if the pressing plate for pressing the fixing nut is divided and installed so that two nuts are provided for each nut, even if a problem occurs in the adjusting bolt or the heater, only one of them can be easily replaced.

[Brief description of drawings]

FIG. 1 is a side sectional view of an extrusion molding die lip adjusting device showing an embodiment of the present invention, FIG. 2 is a sectional view taken along arrow A of FIG. 1, and FIG. 3 is a side sectional view of a conventional die lip adjusting device. 4 is the third
FIG. 5 is a sectional view taken along line BB in FIG. 5, and FIG. 5 is a side sectional view showing another conventional die lip adjusting device. Description of main parts of the drawing 101 …… Die body 101 ′ …… Flexible lip 102 …… Die body 103 …… Holding block 105 …… Stud bolt 106 …… Lock nut 107 …… Screw seat 108 …… Disc spring 109… … Small diameter adjustment bolt 110 …… Large diameter adjustment bolt 111 …… Fixing nut 112 …… Pressing plate 113 …… Rotating pin 120 …… Resin flow passage 121 …… Resin discharge port 123 …… Gap 124 …… Brim 125… … Screw holes

Claims (1)

[Claims] 1. A die lip adjusting device for pushing and pulling a plurality of lips provided in a lip width direction of a die for extrusion molding a molten resin sheet or film, wherein one end is fastened to the die lip and a disc spring is provided at the other end. A stud bolt with a collar for installation, a disc spring with the collar of the stud bolt inserted in the lower part, and a screw fitted into the stud bolt and pressed into the die body to press the disc spring. A large diameter adjusting bolt with a seat and screws with different pitches on the inner diameter side and the outer diameter side, and a small diameter screwed into the inner diameter side of the large diameter adjusting bolt and abutting on the upper end surface of the stud bolt. Equipped with an adjusting bolt and a nut that is screwed into the screw on the outer diameter side of the large diameter adjusting bolt and fixed to the die body via a holding plate.Install the adjusting bolt from the top surface of the die body. For extrusion, characterized in Rukoto die lip adjusting device.