JPH05293872A - Lip interval adjusting device for t-die - Google Patents

Abstract

PURPOSE:To control the thickness of a sheet or the like by covering smoothly the end of a die bolt with a socket based on a simple constitution regardless of any environment such as the temperature condition in which a device is used. CONSTITUTION:A taper 3x is formed on a hexagonal head section 3a of a die bolt 3. On the other hand, a socket 21 for rotating said die bolt 3 4 can be moved reciprocatingly in the direction of axial center of the die bolt 3 by an air cylinder 39 or the like, and can be rotated by a motor 38 or the like through an Oldham coupling 22. The end of an opening of the socket 21 is tapered inward. The depth of said opening is formed in the sufficiently deep dimension so that the end of die bolt 3 is not brought into contact with a bottom section of the opening when the socket 21 is moved by an air cylinder 39 or the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for extruding a resin sheet or the like by using a T die, and more particularly to a device for adjusting a gap between lips at the tip of the T die for controlling the thickness of the sheet. Is.

[0002]

2. Description of the Related Art A T-die is a molding device in which a pair of flat plate-shaped molds are arranged substantially in parallel, and an orifice is formed by a tip portion called a lip. By pressing the molten resin material between the molds, a sheet of the same material can be molded and ejected between the facing lips. Forming a sheet using a T-die is shown, for example, in FIG. In the figure, reference numeral 1 is a T-die, and reference numeral 11 is an extruder, and the sheet A is extruded from between the lips 2a and 2b at each tip of the T-die 1. Reference numeral 14 is a sensor that measures the thickness of each part of the sheet.

Both or one of the pair of lips is displaced in the sheet thickness direction by tightening or loosening a plurality of die bolts (reference numeral 3 in FIG. 6) arranged at regular intervals in the width direction of the sheet. Thus, the distance from the opposite lip is changed, and the thickness of the sheet to be formed is determined according to the amount of this displacement. Since the thickness of the sheet changes depending on the viscosity of the material, etc., and it is necessary to prevent the thickness from fluctuating in the width direction, it is often necessary to make such adjustment during molding. Further, in a so-called sequential adjustment type T-die, since a plurality of die bolts are operated by one socket, the socket is attached to and detached from the die bolt at each adjustment. For this reason, the adjustment of the lip interval is performed by, for example, moving the socket for rotation operation by the moving means to fit the tip of the die bolt (the end on the operated side), and turning it by an appropriate amount by the rotating means. To take.

When the lip distance is adjusted by the automatic machine as described above, it is important that the tip of the die bolt can be smoothly covered with the socket, in addition to accurately turning the die bolt by a necessary rotation amount. If the socket hits the die bolt and impact or vibration seems to occur,
This is because the sheet to be extruded becomes wavy at that time, and the thickness of the sheet becomes uneven, which may impair the quality.

As a device for smoothly covering the tip portion of the die bolt with a socket, there is a device disclosed in Japanese Patent Publication No. 1-40741. In the device described in the publication, after operating the die bolt, the socket is returned to the neutral angular position (the state where the die bolt does not contact the inner surface of the socket), and the angle (rotation angle) of the socket at that time is stored. Then, the next time you operate the die bolt, set the socket at the same angle and cover the die bolt. The neutral angular position of the socket with respect to the die bolt is an angular position at which the socket smoothly moves in and out of the die bolt. Therefore, if the socket is covered with the die bolt at that angle, it is unlikely that an impact force is generated when the socket is covered.

[0006]

The above-described method of storing the angular position of the socket or the die bolt and adjusting the socket to the angle in advance when the corresponding die bolt is operated is performed by rotating the socket. There is a tendency to have a large amount of control. That is, for example, a sensor for knowing the actual angular position of a socket or the like, a memory section for storing it, and a calculation / control (CPU) section for reproducing it are required. A special motor for control that accurately determines the socket position accordingly is also essential. Since such a control device is not suitable for use in a high temperature atmosphere, special consideration is required when it is applied to a machine having a high operating temperature such as a T-die.

Also, when the above method is adopted, it is necessary to take care not to move the socket moved so as to cover the die bolt too much in the axial direction. If the socket is moved too much, the end of the die bolt hits the bottom of the opening of the socket, which gives an impact force to the die bolt when the socket is completely covered. Particular attention should be paid when the die bolts protrude toward the socket as a result of adjustment.

An object of the present invention is to provide a lip gap adjusting device having a simple structure which does not matter the temperature condition and the like, and which is capable of covering the tip of the die bolt with a socket without exerting an impact force regardless of the protrusion degree of the die bolt. Is to provide.

[0009]

SUMMARY OF THE INVENTION A lip gap adjusting device for a T-die according to the present invention comprises: a) an operated side of a die bolt (a side operated by being covered with a socket; normally, a hexagonal head is formed); While the taper tip is tapered, b) the rotary operation socket of the die bolt can be reciprocated in the axial direction of the die bolt by b-1) moving means, and b-2) Oldham coupling. B-3) a tapered taper is provided at the tip of the opening of the socket, and b-4) the depth of the opening is changed by the moving means to move the socket to the bottom of the die bolt. The size is deep enough that the ends do not come into contact with each other.

[0010]

In the lip interval adjusting device of the present invention, the above-mentioned socket is put on the tip of the operated side of the die bolt at the relevant portion (the portion where the lip is to be displaced to increase or decrease the sheet thickness), and it is turned by an appropriate amount. Adjust the lip spacing near that point by. The movement of the socket for covering the die bolt is performed by the moving means of b-1), and the rotation of the socket thereafter is performed by the rotating means of b-2). However, the above points are not different from the conventional device.

The device of the present invention is characterized in that the operation of covering the tip of the die bolt on the operated side with the socket can be smoothly performed by the following operation.

First, when starting to cover the tip of the die bolt with the socket, the socket is moved toward the die bolt by the moving means while being rotated by the rotating means. As in a) above, the tip of the die bolt is tapered, and as in b-3), the opening of the socket is also tapered, and as described in b-2). Since the Oldham coupling is provided between the socket and the rotating means, the socket smoothly fits into the tip of the die bolt at this time. That is, even if the initial position of the socket is slightly different from the axial center position of the die bolt, the socket is guided on the axial line of the die bolt based on the contact between the tapers and within the allowable eccentricity range of the Oldham coupling. In addition, since the socket moves while rotating, the socket fits nicely on the die bolt. in this way,
When starting to cover the die bolt with the socket, the socket does not make a shocking contact with the die bolt which hinders the movement of the socket, and thus does not exert an impact force or cause vibration.

After the socket is fitted to the tip of the die bolt, the socket is moved a little further in the axial direction to ensure the fitting, but at this time, the end of the die bolt does not hit the bottom of the opening of the socket. Absent. This is because, as described in b-4) above, the depth of the opening of the socket is sufficiently large that the end of the die bolt does not come into contact with the bottom of the die bolt due to the movement of the socket by the moving means. In other words, since the opening has a sufficient depth, no impact force is generated even when the die bolt is completely covered with the socket, regardless of the degree of protrusion of the die bolt toward the socket.

As described above, the device of the present invention has a simple mechanical structure, so to speak, without the use of special control equipment which is not preferable in terms of operating temperature and cost, so that the tip of the die bolt can be smoothly moved. You can cover the socket with. Since the socket can be smoothly covered with the die bolt, there will be no unevenness of the sheet thickness due to impact force or vibration.

[0015]

1 to 6 show an embodiment of the present invention. Figure 6
As described above, in this example, the resin sheet A is extruded from between the lips 2a and 2b of the T die 1. On this sheet A, another sheet B (including canvas) that is preformed and supplied from the reel 12 is provided with a pair of rolls 1.
3 is laminated. Laminated sheets A and B so that the thickness of the sheet A is controlled and the variation in the thickness in the width direction is reduced.
A .beta.-ray type thickness sensor 14 is installed in the path extending to the reel 15 and detects and displays the thickness distribution of the sheets A and B in the width direction. Since the lip 2a of the T-die 1 is provided with a large number of die bolts 3 along the width direction of the sheet A (see FIGS. 1 and 4), it is necessary to rotate them according to the output of the thickness sensor 14. Thus, the lip 2a at the corresponding position is displaced, the gap between the lip 2a on the other side is adjusted, and the thickness control is performed.

As shown in FIG. 4, the lip gap adjusting device of the embodiment has an adjusting unit 20 including a socket 21 for rotating the die bolt 3 on a frame 40 integrally connected to the T-die 1. Is. Die bolt 3
Although there are multiple units, one unit 20 is one set, so
Further, as shown in FIG. 4, the arrangement direction of the die bolts 3 (sheets A and B) is controlled by a mechanism that combines the slide shaft 41, the ball screw 42, and the driving stepping motor 43.
The unit 20 traverses in the width direction.

The adjusting unit 20 is constructed as shown in FIGS. 1 and 3, and the socket 21 is rotated by the rotational driving force of the motor 38, and the socket 21 is fitted into (and removed from) the hexagonal head 3a at the tip of the die bolt 3. Therefore, a part reciprocates in the axial direction of the die bolt 3. In both figures,
Reference numeral 22 is an Oldham joint, 23 is a speed reducer, 32 is a spline shaft, 34 is an intermediate shaft, 36 is a joint for shutting off excessive torque, 37 is a counter (rotation amount detector), 38 is a drive motor, and there are three locations. Is provided with a synchro belt / pulley pair 31, 33, and 35. Socket 21
Is rotationally driven using a motor 38, which is a very general induction motor (connected to an inverter), and a transmission device group connected in this way as a rotation unit. The transmission device from the spline shaft 32 to the socket 21 (including the synchro belt / pulley set 31, the reducer 23, the Oldham coupling 22 and the like as shown in FIG. 1) is integrally formed with the air cylinder 39.
It is arranged to reciprocate using the above as a moving means. Synchronous belt / pulley pair 33 that rotates at a fixed position
On the other hand, since the spline shaft 32 is connected in a variable position in the axial length direction, the spline shaft 32 and thereafter move parallel to the axial length direction of the die bolt 3 while receiving power transmission, that is, in the axial direction of the die bolt 3. You can do it.

In the apparatus of this embodiment, the die bolt 3
The structure shown in FIG. 2 is provided so that the socket 21 can be smoothly fitted into the hexagonal head 3a at the tip of the die bolt 3 by the above-mentioned movement of the socket 21 and the like toward the axial direction.
That is, first, a tapered taper 3x is formed on the hexagonal head 3a of the die bolt 3, and a tapered taper 21x is formed on the tip of the opening 21a of the socket 21. This point is also related to the provision of the Oldham joint 22 as described above, and the die bolt 3 is connected to the socket 21.
When the cover 21 is covered, the socket 21 can be aligned with the axial center of the die bolt 3 by the force based on the contact between the tapers 3x and 21x and the function of the joint 22 that allows eccentricity. In FIG. 2 (a), reference numerals 22a and 22c of the joint 22 are parts (hubs) integrally connected to the socket 21 and the reduction gear 23 (the output shaft thereof), and the reference numeral 22b is a so-called floating cam. is there. The opening 21a of the socket 21 is shown in FIG.
As described above, a so-called dodecagonal hole is formed so that the hexagonal head 3a of the die bolt 3 can be fitted only by rotating at most 30 °.

Secondly, the opening 21a of the socket 21 is made sufficiently deep. This is the socket 21 with the die bolt 3
The die bolt 3 on the bottom portion 21b of the opening 21a.
The impact d is prevented from being generated by hitting against the edge, and the depth d of the opening 21a shown in FIG. 2 (a) is set to be equal to or larger than the moving amount of the head 3a of the die bolt 3. The position of the tip of the socket 21 at the highest position is the die bolt 3
The stroke of the air cylinder 39 is set so that the socket 21 is always in the hexagon head 3 of the die bolt 3.
However, since the depth d is set as described above, the die bolt 3 does not hit the bottom portion 21b of the socket 21 when the socket 21 descends.

Based on the first and second structures, the socket 21 can be smoothly fitted into the hexagonal head 3a of the die bolt 3. For this purpose, first, as described above, the adjusting unit 20 is traversed in the arrangement direction of the die bolts 3 to determine the approximate position of the socket 21 at the axial center position of the die bolt 3 to be adjusted, and then the socket 2
1 and the like may be moved toward the die bolt 3 by moving means such as an air cylinder 39 while lightly rotating the rotating means such as the motor 38 shown in FIG. The above taper 3x ・ 21x
The shaft center of the socket 21 is smoothly guided by the action of the Oldham coupling 22 and the die bolt 3 does not hit the bottom portion 21b of the socket 21 even when the air cylinder 39 is expanded or contracted by the maximum stroke. The impact force does not work.

In addition, in this embodiment, the magnitude of the torque transmitted to the socket 21 for rotating the die bolt 3 is replaced with the displacement of the casing of the speed reducer 23 to change the magnitude of the displacement (on / off binary signal). Based on this, the effective rotation amount of the die bolt 3 (which does not correspond to play or play) is detected. Since the rotation of the die bolt 3 includes a rotation portion that is not effective due to play such as a screw portion or play, it is necessary to exclude it from the effective rotation amount based on the torque during rotation. With the example, there is no need to detect the torque magnitude itself,
This is because the measuring instruments can be extremely simplified (and it is advantageous in terms of usage environment and cost). Specifically, in the adjusting unit 20, first, the speed reducer 23 is provided in FIG.
As shown in the drawing (below), the sleeve 23a is integrated with the outside of the casing by the bolts 23b, and the bearing 24 and the support frame 25 are provided on the outer periphery thereof. As a result, the speed reducer 23 is rotatable within the support frame 25 moved by the air cylinder 39. Then, as shown in FIG. 3, the tip of the spring plunger 26 having the fixed base is attached to the speed reducer 2.
The protrusion 23x on the upper part 3 is used to stop the rotation of the casing. Further, the thin iron plate 23y is attached to the projecting piece 23x, and the proximity switch 27 is arranged facing it. Since the speed reducer 23 rotates in both forward and reverse directions, the number of switches 27 is two as shown in the figure.

When the rotational torque transmitted to the socket 21 is applied to the speed reducer 23, the casing of the speed reducer 23 is rotationally displaced against the spring force of the spring plunger 26, and the iron plate 2
When 3y approaches the proximity switch 27 for a certain amount or more, the switch 27 is turned on. Since the displacement and the spring force have a linear relationship in the plunger 26, this rotational displacement is proportional to the rotational torque of the speed reducer 23. Therefore, in the adjustment unit 20, the socket 2 is
1 is a constant value-that is, the socket 21
When the lip 2a is effectively displaced, not when the die bolt 3 or the like rotates in the play or play range.
The switch 27 is turned on when the value equal to or more than the value set to correspond to the torque applied to is greater than or equal to.

The counter 37 shown in FIG. 3 detects the rotation amount (rotation angle) of the socket 21 by replacing the number of pulses with the rotation of the radial protrusions 37a with the number of pulses and counts the number of pulses. The count is performed only when the switch 27 is turned on.
When the switch 27 is off, that is, when the torque applied to the socket 21 is small, the die bolt 3 is rotating within the play or play range. Therefore, the rotation amount can be detected only when the switch 27 is on. For example, it is possible to know the effective rotation amount of the die bolt 3.

FIG. 5 is a flow chart showing the operation procedure of the apparatus including the above points. The die bolt 3 to be adjusted based on the output of the thickness sensor 14 (FIG. 6)
When the operator sets the number (position in the width direction of the sheets A and B) and the required rotation amount thereof in the input mode, the present apparatus starts the following automatic operation. That is, first, the adjustment unit 2 is moved to the position of the corresponding die bolt 3.
0 (socket 21) traverse and position it, socket 2
1 is lightly rotated and lowered to fit the socket 21 into the die bolt 3. A switch (not shown) provided at the lower limit position is turned on and a predetermined time has elapsed, and then the socket 21 is started to rotate again. Then, the counter 37 detects the rotation amount from the time when the proximity switch 27 is turned on, and when it reaches the set value, the socket 21
Stop and remove from the die bolt 3 (the adjustment unit 20 is moved upward). In addition, if the die bolt 3 to be adjusted is set in the input mode, the socket 21 and the like together with the unit 20 are moved to the position of the die bolt 3 and the same operation as above is performed. It is also possible to automate the input mode by receiving the output of the thickness sensor 14 (the setting by the operator is unnecessary).

[0025]

The T-die lip gap adjusting device according to the present invention has the following effects. In other words, 1) When the socket is put on the die bolt at the corresponding position to adjust the lip distance, the socket fits smoothly into the tip of the die bolt even if the position is slightly different from the axial center position of the die bolt. ..

2) Not only when the socket is put on the die bolt as in 1) above, but also when the socket is completely covered, impact force or the like does not act on the die bolt (and this is , It does not change depending on the degree of protrusion of the die bolt within the adjustment range.)
Distortion of thickness is unlikely to occur in products such as sheets formed by T-die.

3) Since there is no need to use special control equipment, there are no restrictions on the operating environment such as temperature conditions, the cost is low, the configuration is easy, and there are few failures.
There are also merits.

[Brief description of drawings]

FIG. 1 is a side view generally showing an apparatus as an embodiment of the present invention including a T-die 1.

2 (a) is a main part of the apparatus of FIG. 1 (in FIG.
(Part II) is a detailed side view showing a part of the cross section.
It is a bb arrow line view in the same (a).

3 is a front view showing an adjusting unit 20 in the apparatus shown in FIG. 1 (a view taken along an arrow line III-III in FIG. 1).

FIG. 4 is a plan view (IV-IV arrow view in FIG. 1) of the apparatus of FIG.

5 is a flowchart showing an operation procedure of the apparatus of FIG.

FIG. 6 is a schematic view showing a molding process of a resin sheet using the T die 1 and the like.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 T die 2a / 2b Lip 3 Die bolt 3x Taper 20 Adjustment unit 21 Socket 21a Opening 21b (of socket 21) Bottom 21x (Opening 21a) Bottom 21x Taper 22 Oldham coupling 38 Motor (part of rotating means) 39 Air cylinder (moving means) Part of) A resin sheet

Claims (1)

[Claims] 1. An apparatus for adjusting a lip interval at a tip of a T die by rotating a die bolt to control a thickness of a resin sheet or the like when the T die is used for extrusion molding. While tapering the tapered tip of the operated side of the, the rotary operation socket of the die bolt can be reciprocated in the axial direction of the die bolt by the moving means and can be rotated by the rotating means via the Oldham coupling. , A tapered taper is provided at the tip of the socket opening,
Further, the depth of the opening is adjusted so that the end of the die bolt does not come into contact with the bottom of the socket when the socket is moved by the moving means.