JP4612612B2 - Forming roll, thin film forming apparatus and thin film forming method - Google Patents

Description

  The present invention relates to a forming roll used for forming a sheet material, and more particularly to a forming roll capable of adjusting a crown. The present invention also relates to a thin film forming apparatus having the forming roll and a thin film forming method using the thin film forming apparatus.

  In the present invention, “linear pressure” means a force (N) per length (cm) when a pair of rolls are pressed against each other, and is also called a nip pressure. In the present invention, the term “crown” means that when a pair of rolls are pressed against each other, the rolls bend and the linear pressure at the center of the roll width decreases, so that the roll outer diameter is made thicker in advance than the end. . By performing crown processing, a uniform linear pressure in the width direction can be obtained when a load is applied. When the diameters of the center and end of the roll are D1 and D2, the crown C = D1−D2 (diameter difference). Accordingly, the crown for the radius is C / 2.

  Conventionally, as a roll for press-molding a long sheet-like material with a pair of rolls, a roll using a hydraulic equal pressure, a crown adjusting roll using a number of hydraulic pistons, and the like have been disclosed (Patent Document 1). 2).

  Further, as a roll for manufacturing a resin film / sheet, Patent Document 3 discloses a forming roll provided with an outer cylinder made of a thin metal thin film that can be elastically deformed, and an elastic body roll that can be elastically deformed and rotated inside the outer cylinder. Is disclosed. Patent Document 4 discloses a double pipe roll having a thin outer cylinder thickness t of 0.03 or less of the roll radius.

Further, Patent Document 5 discloses a roll that adjusts the amount of roll crown with an eccentric cam to adjust the bending of the rubber-covered roll to prevent meandering and wrinkling of the conveying sheet.
Japanese Patent Publication No. 58-46599 JP-A-6-65889 Japanese Patent No. 3422798 JP 11-235747 A Japanese Patent Laid-Open No. 2-255 211

  However, in the case of the rolls disclosed in Patent Document 1 and Patent Document 2, a uniform nip can be obtained. However, a hydraulic device is necessary, and the apparatus becomes large and expensive.

  Further, in the case of the roll disclosed in Patent Document 3, the outer cylinder can be molded as a thin cell of about 1 mm so as to be softly wound around the counterpart molding roll, and a thin sheet can be molded. There is no driving means for the outer cell. Further, in FIG. 16 in which the outer cell is backed up by the inner roll, if the linear pressure is increased, the deformation of the outer cell is increased and the life is shortened. If the inner roll is pressed against the outer cell in advance, the rubber and the outer cell are partly permanently deformed and a precision molded sheet cannot be formed.

  In the case of the roll disclosed in Patent Document 4, it is a forming roll in which the outer cylinder is made thin with a double pipe roll for forming a thin precision sheet, but when the linear pressure (nip pressure) is changed, There is a problem that uniform pressure cannot be obtained. Also, when the linear pressure is doubled, the stress of the outer cell differs in the width direction, but on average it doubles, and at the end of the roll, it becomes six times, and the durability deteriorates. narrow. Therefore, it cannot adapt to the demand to change the nip pressure in accordance with the thickness of the sheet to be molded and the change of the material. Further, since the linear pressure load is borne at the end of the outer cylinder, the linear pressure cannot be increased. Also, crown adjustment is not possible.

  In the case of the roll disclosed in Patent Document 5, the heat conductivity of the rubber is poor and the heat inside the roll cannot be transmitted, so the sheet material cannot be cooled and heated from the rubber roll side. There is no cell driving means.

  Therefore, an object of the present invention is to provide a forming roll, a thin film forming apparatus, and a thin film forming method capable of adjusting a crown with a simple structure.

  In order to solve the above problems, a forming roll of the present invention is a double-pipe structure forming roll having an outer cell, an inner roll provided in the outer cell, and a rubber covering the inner roll. A hollow shaft having a hollow structure is provided at both ends of the cell, the hollow shaft is rotatably supported by bearings disposed on both sides of the forming roll, and at least a driving means for driving the forming roll is connected. The drive side bearing is housed in a bearing housing, and the inner roll is rotatably supported by each boss portion of the inner roll shaft having two boss portions with an eccentric radius R2, and both ends of the inner roll shaft are The crown adjustment cam is inserted through a hole of a crown adjustment cam in which a hole having an eccentric radius R1 is formed, and each crown adjustment cam is rotatably supported by a bearing concentric with the bearing provided in the hollow shaft. Adjustment cam rotation By changing the degree, characterized in that the axial position of the inner roll is adjusted radially.

  The forming roll of the present invention as described above includes crown adjustment cams at both ends of the inner roll shaft, and the crown adjustment cam is used to adjust the crown amount by adjusting the axial center position of the inner roll in the radial direction. Can do. For this reason, it is not necessary to provide a hydraulic device for crown adjustment in the outer cell, and the crown amount can be adjusted with a simple structure. Further, in order to obtain a uniform linear pressure in the width direction of the outer cell, it is possible to individually adjust the crown adjusting cams at both ends of the inner roll shaft.

  The crown adjusting cam of the forming roll of the present invention has a cam lever extending in the radial direction of the hole, and a fixed pin slidable in the axial direction of the inner roll shaft at the tip of the cam lever. A plurality of holes into which the fixing pin is inserted are formed in the circumferential direction of the inner roll shaft, and the rotation angle of the crown adjusting cam is changed by rotating the cam lever, and the crown adjusting cam is inserted by inserting the fixing pin into the hole. The rotation angle may be positioned.

  Alternatively, the crown adjusting cam of the forming roll of the present invention is provided with a crown adjusting gear on its outer periphery, and the rotation angle of the crown adjusting cam is changed by rotating the crown adjusting gear with a motor. Also good.

  Further, the inner roll shaft of the forming roll of the present invention may have a rotation fixing device that prevents the rotation of the inner roll shaft itself.

  Further, the inner roll shaft of the forming roll of the present invention may be formed with a flow path through which the temperature adjusting liquid flows and a hole through which the temperature adjusting liquid flows in and out. In the case of this configuration, the temperature of the outer cell can be kept constant because the temperature adjustment liquid circulates and fills the inside of the outer cell. Therefore, the sheet material can be cooled and heated without being affected by the thermal conductivity of the rubber coated on the inner roll.

  Further, the bearing of the molding roll of the present invention is housed in bearing boxes disposed on both sides of the molding roll, and the bearing provided on the operation side opposite to the driving side is concentric with the bearing and has a shaft core. It may be arranged at a position shifted in the direction toward the forming roll and at a position in contact with the outer periphery of the crown adjusting cam and the inner periphery of the hollow shaft.

  The thin film forming apparatus of the present invention is a thin film forming apparatus that forms a thin film by narrowing a molten resin extruded from a T die with a plurality of forming rolls, and is fixedly disposed to face the forming roll of the present invention and the forming roll. And a forming roll.

  Moreover, the thin film forming apparatus of this invention may have a pressing adjustment apparatus which makes each bearing box which carries out rotation support of the forming roll slide in the direction of a forming roll.

  The thin film forming apparatus of the present invention may also have a direct drive motor that directly drives the hollow shaft. In this configuration, since the outer cell can be driven, it is suitable for forming a thick sheet that requires driving both nip rolls, and can be formed without applying shear strain in the thickness direction of the resin molded sheet. A sheet for optical use can be formed.

  The thin film forming method of the present invention is a method of forming a thin film by narrowing the molten resin extruded from a T die with a plurality of forming rolls. It includes a step of adjusting by changing the rotation angle of each crown adjustment cam.

  The forming roll of the present invention is provided with crown adjusting cams at both ends of the inner roll shaft, and the crown amount can be adjusted by adjusting the axial center position of the inner roll in the radial direction with these crown adjusting cams. For this reason, the crown amount can be adjusted with a simple structure.

  FIG. 1 shows a configuration of a film forming machine as an application example of the forming roll of the present embodiment. 2 is a cross-sectional view taken along line AA of the forming roll 20 shown in FIG. 1, and FIG. 3 is an arrow view in the BB direction in FIG. 2 showing the arrangement of the crown adjustment holes.

  The film forming machine of this embodiment includes a T die 24, a forming roll 20 having the characteristics of the present invention, and forming rolls 21 and 22. The forming rolls 20, 21, and 22 are arranged in parallel.

  The T die 24 extrudes a resin material from an extruder (not shown) into a sheet shape and guides it to a nip gap between a pair of molding rolls 21 and 20. Examples of the sheet 25 include a transparent clear sheet having a thickness of about 0.05 mm to about 3 mm, and PC (polycarbonate) and PMMA (polymethyl methacrylate) resin materials. The forming roll 21 is fixedly installed, and the other forming rolls can be moved in the horizontal direction by a pressing device. The forming rolls 21 and 20 usually rotate at the same speed, and are formed to a constant thickness with a uniform pressure on the roll width. The sheet 25 is wound around the forming roll 21 side, nip-formed by the forming roll 22, then flowed downstream and cooled, and then wound or cut to produce a sheet.

  An example of main specifications of the forming roll 20 is shown in Table 1.

  The forming roll 20 of the present embodiment includes an outer cell 1 driven by a DD (direct drive) motor 27 and a high-rigidity inner roll 2 provided in the outer cell 1 with a double tube structure.

  The outer cell 1 has hollow shafts 6 fixed at both ends with bolts 43, and these hollow shafts 6 are rotatably supported by bearings 36 provided in a bearing box 39. The DD motor 27 held in the bearing box 39 by the support 18 directly rotates the hollow shaft 6 inserted into the hollow hole 45. Since the DD motor is supported by the bearing 36, it can slide together with the roll in the direction of the counterpart roll 21, so that a drive shaft such as a universal joint is unnecessary, and a speed reducer is also unnecessary. A commercially available DD motor 27 can be used. When the hole diameter of the shaft of a commercially available DD motor is small, the DD motor is installed in the portion of the shaft 57 of the crown adjusting cam 12 with the hole and outer diameter of the hollow shaft 6 being reduced.

  As shown in FIG. 2, the outer cell 1 employs an outer flange type on the drive side and an inner flange type on the operation side. The drive side has a structure in which the inner roll 2 is easily pulled out because the flange does not protrude from the outer cell 1. Further, the outer cell 1 can be replaced only when the surface is scratched or dents. The outer cell 1 is extracted and replaced on the operation side (the side opposite to the drive side on which the DD drive 27 is provided). The cell thickness of the outer cell 1 should be flexible when the sheet is thin (for example, 0.5 mm or less), so it is made thin (about 0.2 to 4 mm), and when forming a thick sheet, the linear pressure is also large. Therefore, it is preferable to increase the cell thickness.

  The outer circumference of the inner roll 2 is covered with a rubber 3, and the rubber surface is usually provided with a crown for bending the inner roll 2 as shown in FIG. 4. Since rubber is soft, it bends more than a metal such as iron, and the sheet at the nip can have a uniform linear pressure distribution across the roll width. Further, since the linear pressure is applied via the outer cell 1, a more uniform linear pressure distribution can be obtained when the outer cell 1 is thin. Although the deflection of the inner roll 2 increases according to the magnitude of the linear pressure, the rubber 3 may be crowned when the linear pressure is high. When the linear pressure is as large as 1000 N / cm, the rubber strength is increased and the outer cell 1 is thickened.

  Moreover, since the inner roll 2 has a highly rigid structure to support a load and the inner roll 2 is highly rigid, the outer cell 1 can be made thinner than a general roll as described above. .

  The bearing box 39 of the bearing 36 can be slid on the rail 41 by the slider 40 (see FIG. 4), and can move back and forth in the direction of the forming roll 21. The movement is performed by the pressing device 26, and a nip (linear pressure load) can be applied to the sheet between the forming rolls 20 and 21.

  The inner roll 2 disposed inside the outer cell 1 is pivotally supported so as to be rotatable with respect to the inner roll shaft 4. Two bearings 37 that are eccentric from the center of the outer cell 1 and centered on the inner roll shaft 4 are fitted into both ends of the inner roll 2, and the inner roll 2 can rotate freely.

  The inner roll shaft 4 has two eccentric boss portions 44, and the bearings 37 of the inner roll 2 are attached to the boss portions 44. The amount of eccentricity between the inner roll shaft 4 and the boss portion 44 is R2.

  Crown adjustment cams 12 are provided at both ends of the inner roll shaft 4. In other words, an eccentric hole 12a is formed in the crown adjustment cam 12, and the inner roll shaft 4 is fitted in the hole 12a. The crown adjusting cam 12 is pivotally supported by a bearing 36 fitted in the hollow shaft 6. The amount of eccentricity of the crown adjustment cam 12 is R1, and there is a function of moving the inner roll shaft 4 slightly in the roll radial direction by turning the crown adjustment cam 12. A cam lever 13 extending in the radial direction is welded to the crown adjusting cam 12. A fixing pin 14 is slidable in the axial direction at the tip of the cam lever 13. As shown in FIG. 3, the fixing pin 14 is fitted into a hole 15 arranged in the circumferential direction of the bearing box 39 to fix and position the crown adjusting cam 12 at a predetermined rotational position. About ten holes 15 are provided on one side connecting the upper and lower stop points of the circumference.

  The eccentric amount by the crown adjusting cam 12 is changed by rotating the cam lever 13. First, the fixing pin 14 is removed from the hole 15 and the eccentric amount can be determined by the scale 56 as will be described later. The cam lever 13 is rotated to set the fixing pin in the target hole 15. The cam lever 13 is manually operated when the operation is stopped, and a lever lever jig is used when the friction is large.

  As shown in FIG. 2, a shaft 57 is bolted to the crown adjustment cam 12 on the driving side, the cam lever 13 extends in a radial direction from the shaft 57, and the fixing pin 14 is slidably provided at the tip thereof. It has been. Since the crown adjusting cam 12 and the inner roll shaft 4 are rotated for eccentric adjustment, a lubrication or dry type sliding bush is provided to enable smooth rotation. The cam adjustment amounts of the crown adjustment cams 12 provided on both sides of the inner roll shaft 4 are basically the same on both sides, but can also be adjusted individually.

  The inner roll shaft 4 is provided with a lever-shaped rotation fixing device 11 extending in the radial direction at the end on the operation side. A fixing pin 10 is slidable in the axial direction at the tip of the rotation fixing device 11. The rotation fixing device 11 is not provided on the driving side. As shown in FIG. 3, the fixing pin 14 of the rotation fixing device 11 is fitted into a long hole 23 formed in the bearing box 39, so that the inner roll shaft 4 is fixed so as not to rotate. Since the long hole 23 extends in the nip direction, the inner roll shaft 4 can move in the nip direction within a range restricted by the long hole 23. As will be described later, the inner roll shaft 4 moves slightly, but also moves in a direction perpendicular to the nip direction (nip point deviation shown in FIG. 5).

  The inner roll shaft 4 is supported by a bearing 38 provided on the outer periphery of the crown adjustment cam 12, and the bearing 38 and the bearing 36 are disposed so as to overlap each other. The bearing 38 of the inner roll shaft 4 is a self-aligning type bearing and has a structure that does not generate a moment even if the left and right eccentricity changes.

  Inside the inner roll shaft 4, there are formed two series of flow passages 9a, 9b that can enter and exit from the operation side, and penetrate the inside of the outer cell 1 to the operation side and the drive side, respectively. The temperature adjusting liquid 16 for cooling or heating the forming roll 20 is connected to a temperature adjusting device provided outside, and the temperature is adjusted. The temperature adjusting liquid 16 flows from the flow path 9a of the inner roll shaft 4 on the operation side, passes through the hole on the drive side shaft, flows outside the inner roll 2 while contacting the inner surface of the outer cell 1, and flows on the operation side flow path 9b. Spill from. Therefore, the inside of the outer cell 1 is filled with the temperature adjusting liquid 16 in a circulating manner, and the temperature of the outer cell 1 can be kept constant. Since the temperature adjusting liquid 16 is present inside the roll, seals 8a, 8b and 8c are provided to prevent inflow into the bearing and leakage to the outside. Each bearing 36, 37, 38 is provided with a greasing hole that can be lubricated from the outside. Also, an air vent hole 59 is provided in the inner roll 2 in the inner roll shaft 4 so that the temperature adjusting liquid leaks to the outside when the seal 8b is broken. The air vent hole 59 is also a hole through which air enters and exits to avoid fluctuations in the internal air pressure associated with changes in roll temperature. With such a structure, a bearing damage accident can be prevented and detected in advance.

  Next, the adjustment of the eccentric amount by the crown adjustment cam 12 will be described.

FIG. 4 is a diagram for explaining the amount of eccentricity of each part, and FIG. 5 is a diagram for explaining the amount of eccentricity of each part in more detail. FIG. 4 is a cross-sectional view of the roll viewed in the axial direction, and shows the positional relationship between each shaft, roll, and cam. The center O ₁ of the outer cell 1 coincides with the centers of the bearings 36 and 38 and the crown adjusting cam 12.

  FIG. 4 shows a state in which backup of the inner roll 2 to the outer cell 1 (loading of linear pressure load) starts at a position where the inner roll 2 contacts the inner surface of the outer cell 1. If the inner roll 2 is further moved closer to the outer cell 1 from this position, the backup becomes larger, and if it is moved away, the backup is lost. If this position is demonstrated in FIG. 3, the cam lever 13 is a position of F0 (crown zero point). If the cam lever 13 is further rotated to F1 and F2, the crown adjusting cam 12 rotates and the eccentric amount E increases, and the crown increases. When the cam lever 13 is set to F6 (maximum crown point), the amount of eccentricity E becomes maximum and the maximum crown is obtained. Conversely, when the cam lever 13 is set to -F3 (resting point), the amount of eccentricity E is minimized, the inner roll 2 is separated from the inner surface of the outer cell 1, and is rested. Since no load is applied to the inner roll 2 in the resting state, the rubber 3 can be prevented from permanent deformation. A scale 56 indicating the amount of eccentricity is engraved around the hole 15 of the bearing box 39 on both sides of the roll. Thereby, the amount of eccentricity can be discriminated from the outside and adjusted to a predetermined amount of eccentricity.

  Next, the amount of eccentricity will be described in more detail with reference to FIG.

  When the crown adjusting cam 12 is turned, the inner roll shaft 4 also tries to rotate. However, since the fixing pin 10 of the rotation fixing device 11 is in the elongated hole 23 of the bearing housing 39, the inner roll shaft 4 itself is Does not rotate. However, the center P of the inner roll shaft 4 moves on the circumference of a circle indicated by the eccentric radius R1 of the crown adjusting cam 12. Accordingly, the fixing pin 10 moves linearly in the long hole 23.

  When the rotation angle of the crown adjustment cam 12 is an angle α, the eccentricity E = R2 + R1cos α is expressed. The angle α is 0 at the maximum crown position.

  As described above, since the center P of the inner roll shaft 4 moves on the circumference of the circle indicated by the eccentric radius R1, the straight line connecting the center P of the inner roll shaft 4 and the center of the fixing pin 10 and the nip direction A minute angle θ is generated between However, this small angle θ is small, and the deviation δ of the nip point in the direction intersecting the nip direction can be ignored. In the shape of Table 1, θ = 0.6 °, and the nip point deviation δ is about 3.3 mm, both of which are small.

  The outer cell 1 may be a cell with a crown or a normal cylindrical cell. The spring constant of the rubber layer of the inner roll 2 is determined by calculation based on rubber hardness, strength resistance and thickness.

  The roll pressing device 26 is a device that moves the bearing housing 39 in the nip direction, and the roll pressing device 26 moves the slider 40 of the bearing housing 39 along the rail 41. The roll pressing device 26 can apply a nip load to the counterpart roll 21 or move backward to move the roll 20 open.

  The forming roll of the present embodiment having the crown adjusting function as described above is suitable for forming a thin clear sheet.

  When the sheet thickness is as thick as about 2 mm, the residual stress is small even if the linear pressure is increased. On the other hand, when the sheet is thin, residual stress tends to remain due to uneven thickness and linear pressure, and when the sheet thickness is 0.5 mm or less, a portion that cannot be roll-pressed easily due to uneven thickness of the sheet. Since this part does not become a mirror surface, it is better that one of the rolls has flexible followability.

  The forming roll 20 of the present embodiment can obtain a substantially uniform linear pressure even if the linear pressure is changed by 10 times or more using the elasticity of the rubber roll (see the lines (a) and (d) in FIG. 8). By increasing the linear pressure, it is possible to cope with uneven sheet thickness. In addition, the linear pressure distribution in the sheet width direction can be adjusted by the crown adjusting cam 12, the thin portion can be pressed with priority, and sheet defects can be reduced. Further, if the thickness of the outer cell 1 is reduced, the flexibility of the outer cell surface increases, and it becomes easier to follow the deformation of the counterpart roll 21 and uneven thickness of the sheet material, and even a thin sheet that is quickly cooled can be press-formed without unevenness.

In addition, since the forming roll 20 of the present embodiment can be formed with a low linear pressure, it can be formed without applying excessive residual stress to the sheet, and the properties such as the sheet refractive index and retardation, which are problematic in liquid crystal applications, are uniform. It is possible to form a sheet for optical use.
Example 1
FIG. 6 shows a deformation model 1 in which the inner roll shaft 4 is in the maximum eccentric state and an excessive crown is applied to the outer cell 1.

  The cam lever 13 is positioned by inserting the fixing pin 14 into the hole 15 at the position F6. Since R1 = 2 mm in Table 1, the crown radius is 2 mm, and the outer cell 1 competes with the inner roll 2 on the forming roll 21 side and deforms into a convex shape. The inner roll shaft 4 is bent concavely inside the roll. In actual operation in Table 1, the crown radius may be about 0.5 mm, and the remaining 1.5 mm is a margin value.

  FIG. 7 shows a deformation model 2 at rest.

  The cam lever 13 is positioned by inserting the fixing pin 14 into the hole 15 at the position of -F3. In the hole 15, since F0 is a crown zero point, a clearance of 2 mm is generated between the inner roll 2 and the outer cell 1 at -F3. When the roll device is paused for a long time, the cam lever 13 is set from F0 to -F3.

Next, various nip distributions when the crown is adjusted in the forming roll of the present invention are shown in FIGS.
Can be adjusted.
・ Figure 8, Uniform nip (a)
(A) shows the uniform nip obtained by adjusting the cam lever 13 to F1 to F6 by using a rubber crown that makes the inner roll 2 flat at the set linear pressure. The linear pressure makes the load of the pressing device 26 a predetermined force. Also, the force on the operating side and the driving side are made equal. The deflection and rubber deformation of the roll are calculated and set, but it is preferable that the actual linear pressure state is confirmed and set by inserting it into the nip portion of the rolls 20 and 21 with linear pressure detection paper.
・ Figure 8, Convex line pressure distribution (b)
(B) shows a convex linear pressure distribution obtained when more crowns are attached than the uniform nip of (1) above. The center of the roll tends to swell, but when the outer cell is thin, the force of the shaft 6 to the outer cell 1 does not reach the center, and the center becomes flat.
・ Fig. 8, concave line pressure distribution (c)
(C) shows the concave linear pressure distribution obtained when the crown is attached less than the above (1).
・ Figure 8, Uniform nip distribution with varying linear pressure (d)
(D) shows the uniform nip obtained by making the load of the pressing device 26 smaller than in the case of (a). The (a) line shows an example in which a load of about 10 times the (d) line is applied. That is, the (d) line is an example in which a load of about 1/10 is applied to the load of the (a) line. The force on the operating side and the driving side are equal, and the cam lever 13 is shifted to the F1 side. Further, the position of the cam lever 13 is confirmed by performing a test by inserting the linear pressure detection paper into the nip portion of the rolls 20 and 21. If the inner roll 2 has a soft rubber hardness and a large thickness, the rubber elastic modulus decreases, and a uniform nip can be obtained even when the design point is deviated. Further, when the inner roll 2 cell wall thickness is increased, the inner roll 2 deflection is reduced and a uniform nip is obtained. In the example of Table 1, since the designed linear pressure is as small as 50 N / cm, the nip is small and a sufficiently uniform nip can be obtained even at 10 to 100 N / cm.
・ Figure 9, Inclined linear pressure distribution (e)
(E) shows a linear pressure distribution in which the operating side is set low and the driving side is set high. The operation side reduces the force of the pressing device 26 and reduces the amount of eccentricity. The drive side is reversed. Further, the amount of eccentricity may be the same on the left and right, and only the force of the pressing device 26 may be changed on the left and right.
・ Figure 9, waveform linear pressure distribution (f)
(F) is a distribution in which the average of the linear pressure is the same on both the operating side and the driving side, and the whole is a waveform. The force of the pressing device 26 is the same on the left and right, and the amount of eccentricity is changed left and right. The operating side increases the amount of eccentricity, and the driving side decreases the amount of eccentricity. As described above, when the amount of eccentricity is changed to the left and right, the four axial centers of the inner roll shaft are inclined. However, since the bearing 38 is a self-aligning type bearing box 39, no galling or galling occurs.
(Example 2)
FIG. 10 is a partially enlarged sectional view of a crown adjusting cam portion in a forming roll according to another embodiment of the present invention. Hereinafter, the same components as those in the above-described embodiment will be described using the same reference numerals.

  The crown adjusting cam 12 shown in FIG. 10 has a crown adjusting gear 51 fitted on the outer periphery thereof and accommodated in a case 53. The case 53 is rotatably supported by the crown adjustment cam 12 and is fixed to the bearing housing 39 by a rotation pin 54. The crown adjusting cam 12 has a bush 58 to reduce friction with the inner roll shaft 4. The pinion gear 52 fitted on the shaft of the motor 50 meshes with the crown adjustment gear 51 and the motor 50 is driven so that the crown adjustment cam 12 can be continuously finely adjusted. Note that the crown adjustment gear 51 and the pinion gear may be a combination of a worm wheel and a worm gear having a detent function.

An arrow 55 is provided in the eccentric direction of the crown adjusting cam 12 so that the eccentric direction of the inner roll shaft 4 can be discriminated, and a scale 56 indicating the amount of eccentricity is inscribed on the case 53. As a result, the amount of eccentricity can be determined from the outside, and the predetermined amount of eccentricity can be adjusted. A similar device is also provided on the drive side, and the left and right eccentric amounts can be individually set. The eccentricity can be adjusted even during roll operation.
(Example 3)
FIG. 11 is a partially enlarged cross-sectional view of the operation-side crown adjustment cam portion in the forming roll of this embodiment. In addition, the same code | symbol is used about components similar to each Example mentioned above.

  The operation-side bearing 36 that supports the hollow shaft 6 of the outer cell 1 shown in FIG. 11 is disposed at a position separated from the bearing 38 housed in the bearing box 39 by the dimension L toward the forming roll 20. The bearing 36 supports the hollow shaft 6 at a position that is the outer periphery of the crown adjustment cam 12 and the inner periphery of the hollow shaft 6. The drive-side bearing 36 and other structures are the same as those shown in FIG.

  On the operation side, it is not necessary to transmit the drive of the outer cell 1 through the hollow shaft 6, and since the load of the outer cell 1 is small and the rigidity of the inner roll shaft 4 is high in the low load roll, the bending of the inner roll shaft 4 is Small and has little effect on roll function. Therefore, even with the configuration as shown in FIG. 11, the same crown adjustment function as in the example of FIG. 2 can be obtained, and a uniform nip can be obtained in the roll width direction.

As described above, according to the present invention, the following effects can be obtained.
1. Even if the linear pressure is changed, a uniform linear pressure can be obtained over the entire roll width.

Although illustrated in FIG. 8, a uniform linear pressure (nip) can be obtained even when the linear pressure is changed to about 10 times by using the forming roll of the present invention. The change rate of the linear pressure can be adjusted within the limits of the bending effect of the inner roll 2 and rubber elasticity.
2. Fine adjustment of the crown amount is possible.

The forming roll of the present invention can roughly adjust the crown amount by changing the positions and forces of the left and right crown adjusting cams 12 provided on both ends of the inner roll shaft 4 and the left and right pressing devices 26.
3. High cooling and heating capacity for molding materials.

The molding roll of the present invention is a resin film / sheet molding application that requires a temperature control function. Since the temperature control liquid 16 is in direct contact with the outer cell 1 by flowing the temperature control liquid 16 into the molding roll 20, the sheet cooling is performed. High heating ability. Therefore, the sheet can be rapidly cooled or gradually cooled, and physical properties such as transparency and refractive index of the sheet can be improved.
4). Roll drive is possible.

Since the outer cell 1 can be driven, it can be molded without applying shear strain in the thickness direction of the resin molded sheet, and a sheet for optical use can be molded. In particular, when forming a thick sheet, it is necessary to drive both nip rolls. In such a case, the forming roll of the present invention is suitable.
5. A hydraulic device for adjusting the crown is not necessary.

The forming roll of the present invention adjusts the crown amount by changing the amount of eccentricity of the inner roll by the left and right crown adjusting cams 12 provided at both ends of the inner roll shaft 4. This eliminates the need for an expensive hydraulic device inside the roll.
6). A light load roll can be used as a forming roll having a long roll surface length. Since the forming roll of the present invention supports a load with a highly rigid inner roll 2, the outer cell 1 can be made thinner than a general roll. Therefore, it can be set as the forming roll with a long surface length with a light load nip roll. In addition, it is also possible to make it a heavy load roll by changing the thickness of the outer cell 1 and the rigidity of the inner roll 2.
7). A thin clear sheet can be formed. The forming roll of the present invention can form a thin clear sheet of 0.5 mm or less by adjusting the linear pressure by the thin outer cell 1 of about 0.2 to 4 mm and the crown adjusting mechanism of the present invention. It is.
8). The life of the thin outer cell can be increased.

Since the inner roll position can be adjusted with respect to the thin outer cell, deformation of the thin outer cell in the nip portion can be reduced, and the life of the thin outer cell can be extended.
9. It is possible to prevent deformation of the inner roll rubber at rest.

Since the inner roll position can be retracted with respect to the outer cell, permanent deformation of the rubber can be prevented.
10. Can be molded with low linear pressure.

  Since the forming roll of the present invention supports the load with the highly rigid inner roll 2, the outer cell 1 can be made thinner than the general roll. By making the outer cell 1 thin, molding with a low linear pressure is possible, so that molding can be performed without applying excessive residual stress to the sheet. For this reason, properties such as sheet refractive index and retardation, which are problematic in liquid crystal television applications, can be uniformly formed, and sheets for optical applications can be formed.

It is a figure which shows one structure of the film forming machine which is an application example of the forming roll of this invention. It is sectional drawing in the AA of the forming roll 20 of this invention shown in FIG. FIG. 3 is an arrow view in the BB direction in FIG. 2 showing an arrangement of holes for crown adjustment. It is a figure for demonstrating the amount of eccentricity of each part. It is a figure for demonstrating the eccentric amount of each part in detail. It is a figure which shows the deformation | transformation model which made the inner roll axis | shaft the maximum eccentric state and gave the excessive crown to the outer cell. It is a figure which shows the deformation | transformation model 2 at the time of a rest. It is a linear pressure distribution map of the forming roll of the present invention. It is a linear pressure distribution map of the forming roll of the present invention. It is a partially expanded sectional view of the crown adjustment cam part in the forming roll of the other Example of this invention. It is a partial expanded sectional view of the crown adjustment cam part in the forming roll of the further another Example of this invention.

Explanation of symbols

1 Outer cell 2 Inner roll 3 Rubber (rubber coating)
4 inner roll shaft 5 shaft rotation fixing device 6 hollow shaft 8a, 8b, 8c seal 9a, 9b flow path 10, 14 fixing pin 11 rotation fixing device (shaft lever)
DESCRIPTION OF SYMBOLS 12 Crown adjustment cam 13 Cam lever 15 Hole 16 Temperature control liquid 17 Flow path 18 Support 19 Eccentric hole 20, 21, 22 Forming roll 23 Long hole 24 T die 25 Sheet 26 Pushing device 27 DD motor 35 Outer cell 36, 37, 38 Bearing 39 Bearing box 40 Slider 41 Rail 43 Bolt 44 Boss 45 Hollow hole 50 Motor 51 Crown adjustment gear 52 Pinion gear 53 Case 54 Stop pin 55 Arrow 56 Scale 57 Shaft 58 Bush 59 Air vent hole C / 2 Crown (radius)
E Eccentric −F3 Pause point F0 Crown zero position F1-F6 Crown adjustment point R1 Cam eccentric radius R2 Shaft eccentric radius α Angle P Inner roll center

Claims (10)

A forming roll (20) having an outer cell (1), an inner roll (2) provided in the outer cell (1), and a rubber (3) covering the inner roll (2). )
The outer cell (1) is provided with a hollow shaft (6) having a hollow structure at both ends of the outer cell (1),
The hollow shaft (6) is rotatably supported by bearings (36) disposed on both sides of the forming roll (20),
At least the drive-side bearing (36) to which drive means for driving the forming roll (20) is connected is housed in a bearing box (39),
The inner roll (2) is rotatably supported by the boss portions (44) of the inner roll shaft (4) having two boss portions (44) having an eccentric radius R2.
Both ends of the inner roll shaft (4) are inserted into the holes (12a) of the crown adjusting cam (12) in which holes (12a) having an eccentric radius R1 are formed,
Each of the crown adjusting cams (12) is rotatably supported by a bearing (38) concentric with the bearing (36) provided in the hollow shaft (6).
The forming roll characterized in that the axial center position of the inner roll (2) is adjusted in the radial direction by changing the rotation angle of each crown adjusting cam (12). The crown adjusting cam (12) is slidable in the axial direction of the inner roll shaft (4) at the cam lever (13) extending in the radial direction of the hole (12a) and the tip of the cam lever (13). A plurality of holes (15) into which the fixing pins (14) are inserted in the bearing box (39) in the circumferential direction of the inner roll shaft (4). The rotation angle of the crown adjusting cam (12) is changed by rotating the cam lever (13), and the fixing pin (14) is inserted into the hole (15) to rotate the crown adjusting cam (12). The forming roll according to claim 1, wherein the rotation angle is positioned. A crown adjusting gear (51) is provided on the outer periphery of the crown adjusting cam (12), and the crown adjusting cam (12) is rotated by being driven by a motor (28). The forming roll according to claim 1, wherein the angle is changed. The forming roll according to any one of claims 1 to 3, wherein the inner roll shaft (4) has a rotation fixing device (11) for preventing rotation of the inner roll shaft (4) itself. The flow path (9a, 9b) through which the temperature adjusting liquid (16) flows and the hole through which the temperature adjusting liquid (16) flows in and out are formed in the inner roll shaft (4). The forming roll of any one of Claims. The bearing (38) is housed in the bearing box (39) disposed on both sides of the forming roll (20), and the bearing (36 provided on the operation side opposite to the driving side). ) Is concentric with the bearing (38) and shifted to the forming roll (20) in the axial direction, and is in contact with the outer periphery of the crown adjusting cam (12) and the inner periphery of the hollow shaft (6). The forming roll according to any one of claims 1 to 5, which is disposed at a position. In the thin film forming apparatus for forming a thin film by narrowing the molten resin extruded from the T die (24) with a plurality of molding rolls,
A forming roll (20) according to any one of claims 1 to 6;
A thin film forming apparatus comprising: a molding roll (21) fixedly disposed facing the molding roll (20). The thin film forming apparatus according to claim 7, further comprising a pressing adjusting device (26) for sliding each bearing box (39) supporting the forming roll (20) in the direction of the forming roll (21). The thin film forming apparatus according to claim 7 or 8, comprising a direct drive motor (27) for directly driving the hollow shaft (6). In the thin film forming method of forming a thin film by narrowing the molten resin extruded from the T die (24) with a plurality of molding rolls,
The process of adjusting the crown and linear pressure distribution of the said forming roll (20) of the thin film forming apparatus of any one of Claims 7 thru | or 9 by changing the rotation angle of each said crown adjustment cam (12). A thin film forming method comprising:

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