JP2001341194A - Apparatus and method for manufacturing tubular film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tubular film manufacturing apparatus capable of setting the thickness of a tubular film after molding to that of a design dimension by always making the gap between a tubular mold member and a column member at molding temperature constant. SOLUTION: The tubular film manufacturing apparatus, wherein a thermoplastic resin sheetlike film wound in a roll shape within an inner mold is inserted in a tubular mold member having an inner diameter slightly larger than the outer diameter of the inner mold to be subjected to thermoforming, is equipped with a dimension measuring part 201 for measuring the inner diameter of the tubular mold member at the normal temperature and the outer diameter of the inner mold, a calculation part 203 for calculating heating temperature so as to bring the gap between the tubular mold member and the inner mold to a predetermined gap on the basis of the inner diameter dimension of the tubular mold member at the normal temperature and the outer diameter dimension of the inner mold and a temperature measuring part 204 for measuring the temperature of the tubular mold member and that of the inner mold.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer belt used for transferring a precision part to a predetermined position with a high degree of positional accuracy, and a closed package for storing and storing articles. The present invention relates to a manufacturing apparatus and a manufacturing method of a tubular, tubular, ring-shaped, and belt-shaped film, and a main field of application of the present invention is an application as a manufacturing of a functional part of an image forming apparatus.

[0002] A tubular film manufactured by a tubular film manufacturing apparatus according to the present invention is used as a transfer belt of a copying machine, a printer or the like.

[0003]

2. Description of the Related Art In a conventional method for producing a tubular film, an apparatus for forming a seamless belt by using a tubular mold member and a cylindrical member by utilizing a difference in thermal expansion between the tubular mold member and the cylindrical member requires an inner diameter of the tubular mold member in advance. From the design dimensions of the outer diameter of the cylindrical member and the cylindrical member, calculate the gap between the tubular mold member and the cylindrical member at the time of heating, determine the molding temperature, set a molding sheet on the cylindrical member, and set the tubular mold member. Insert inside
By heating while measuring the temperature of the tubular mold member and the cylindrical member, by stopping the heating when the predetermined temperature is reached,
The gap between the tubular mold member having a small coefficient of thermal expansion and the columnar member having a large coefficient of thermal expansion has been narrowed, and the cylindrical member has a thickness corresponding to the gap at the molding temperature.

[0004]

However, a conventional sheet-like film for molding is wound around a cylindrical member.
Inserting into the tubular mold member, heating, crushing the overlapping portion of the end of the sheet-like film using the difference in thermal expansion between the tubular mold member and the cylindrical member, the method of forming the tubular film, the inner diameter of the tubular mold member and The gap between the tubular mold member and the cylindrical member during heating is calculated from the design dimensions of the outer diameter of the cylindrical member, and the molding temperature is determined. Due to the variation in the actual dimensions of the above, the gap between the tubular mold member and the cylindrical member when heated to the molding temperature varies, making it difficult to mold the tubular film to a thickness of the designed dimensions.

[0005] Even if the actual dimensions of the inner diameter of the tubular mold member and the outer diameter of the cylindrical member after processing are as designed, the inner diameter of the tubular mold member is plastically deformed and gradually expanded by repetition of molding. Since the outer diameter of the cylindrical member is plastically deformed and gradually decreases, the gap between the tubular member and the cylindrical member when heated to a certain molding temperature gradually widens. For this reason, it has been difficult to continuously form the tubular film to a thickness of the designed dimensions.

[0006] The tubular film produced by the above method is
When used as a transfer belt for copiers, printers, etc., the difference between the design value and the voltage between the transfer belt and the transfer drum and the distance between the transfer belt and the transfer drum may cause a difference between the design values due to the difference in thickness from the design dimensions. Is difficult to transfer to a desired position, and the image is disturbed.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and always maintains a constant gap between a tubular mold member and a cylindrical member at a molding temperature to design a thickness of a tubular film after molding. It is an object of the present invention to provide an apparatus and a method for manufacturing a tubular film capable of reducing the thickness to a dimensional thickness.

[0008]

Means for Solving the Problems The above-mentioned problems are solved,
In order to achieve the object, an apparatus for manufacturing a tubular film according to the present invention includes a sheet-like film of a thermoplastic resin wound in a roll shape on an inner mold, and an inner diameter slightly larger than an outer diameter of the inner mold. In a tubular film manufacturing apparatus which is inserted into a tubular mold member having a shape and heat-molds, a dimension measuring means for measuring an inner diameter of the tubular mold member and an outer diameter of the inner mold at room temperature, and the tubular at room temperature. Calculating means for calculating a heating temperature such that a gap between the tubular mold member and the inner mold becomes a predetermined gap, based on the inner diameter dimension of the mold member and the outer diameter dimension of the inner mold, and the tubular mold member; Temperature measuring means for measuring the temperature of the inner mold.

The apparatus for manufacturing a tubular film according to the present invention is characterized in that the apparatus further comprises means for measuring the history of the temperature and elapsed time of the tubular mold member and the inner mold.

Further, the apparatus for manufacturing a tubular film according to the present invention is characterized in that the apparatus further comprises means for measuring the history of pressure and elapsed time generated in the tubular film material between the tubular mold member and the inner mold. And

Further, the method of manufacturing a tubular film according to the present invention is characterized in that a thermoplastic resin sheet film wound in a roll shape on an inner mold has an inner diameter slightly larger than the outer diameter of the inner mold. A method for producing a tubular film which is inserted into a tubular mold member and heat-molded, wherein a dimension measuring step of measuring an inner diameter of the tubular mold member and an outer diameter of the inner mold at room temperature, and the tubular mold member at room temperature A calculating step of calculating a heating temperature such that a gap between the tubular mold member and the inner mold becomes a predetermined gap based on an inner diameter dimension of the inner mold and an outer diameter dimension of the inner mold; And a temperature measuring step of measuring the temperature of the mold, wherein when the temperature measured in the temperature measuring step reaches the temperature calculated in the calculating step, at least heating with a temperature rise is stopped. And

Further, the method of manufacturing a tubular film according to the present invention is characterized in that the method further comprises a step of measuring the history of the temperature and the elapsed time of the tubular mold member and the inner mold.

Further, the method for producing a tubular film according to the present invention is characterized in that the method further comprises a step of measuring a history of a pressure and an elapsed time generated in the tubular film material between the tubular mold member and the inner mold. And

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described.

First, the outline of the present embodiment will be described. In this embodiment, in order to determine the molding temperature, means for measuring the inner diameter of the tubular mold member and the outer diameter of the cylindrical member at normal temperature, From the inner diameter of the mold member and the outer diameter of the cylindrical member,
A means for calculating a heating temperature at which a gap between the cylindrical member and the tubular mold member is the same as the design dimension of the thickness of the tubular film, wherein the forming temperature is calculated from the inner diameter of the tubular mold member at room temperature and the outer diameter of the cylindrical member. I have to. In addition, the tubular mold member and the cylindrical member, while heating the film, a means for measuring the temperature of the tubular mold member and the cylindrical member, and when the calculated molding temperature is reached, heating is terminated, the cylindrical member and the tubular mold member Is set to be the same as the designed dimension of the thickness of the tubular film.

Further, the time (heating time) when the tubular mold member, the cylindrical member, and the film are heated from room temperature to the molding temperature.
Since the heating conditions are constant if the heating conditions are the same, the temperature and time histories of the tubular mold member and the cylindrical member are measured, and the time from the start of heating is measured. The heating may be terminated with.

Further, a tubular mold member when the molding temperature is reached,
The pressure (forming pressure) generated in the tubular film material between the cylindrical members is constant if the gap between the tubular member and the cylindrical member is constant. The generated pressure may be measured, and the heating may be terminated when the pressure reaches the molding pressure.

Hereinafter, an embodiment of the present invention will be specifically described with reference to the drawings.

FIG. 1 is a diagram showing a process for producing a tubular film.

In FIG. 1, reference numeral 2 denotes a thermoplastic resin film wound into a roll, 4 denotes an inner mold, 6 denotes a tubular mold member,
8, 10 are sheet films of thermoplastic resin, 8 ', 1
0 'is a tubular film of a thermoplastic resin, 12 is a cooling unit, in which tap water is stored in a water tank as a coolant, but does not affect the cooling air, the inner mold, the tubular film, and the tubular mold member. Depending on the conditions, other liquids may be used.

The dimensions of the sheet film are selected according to the inner diameter of the tubular film to be manufactured, and the sizes of the inner mold 4 and the tubular mold member 6 are selected accordingly. First, in a (1) peeling step of FIG. 1, the thermoplastic resin film 2 wound into a roll is peeled off from the roll, and (2) a cutting step is performed to cut two kinds of sheet-like films 8, 10. Create Next, in the winding step (3), the prepared sheet-like film 8 is wound around the outer peripheral surface of the inner mold 4 so that both ends thereof are overlapped. The width of the overlapping portion at both ends of the film 8 is about 4.0 mm.

Next, the prepared sheet-like film 10 is placed on the outer peripheral surface of the inner die 4 around which the film 8 is wound, so that both ends of the sheet-like film 10 are overlapped with each other. Wind around the other side. The width of the overlapping portion at both ends of the film 10 is also about 4.0 mm. Next, (4) the films 8, 10 wound around the inner mold 4 in the inserting step are inserted into the hollow portion of the tubular mold member 6 as shown in FIG. (5) In the heating step, the inner mold 4, the films 8, 10 and the tubular mold member 6 are placed in a heating furnace and heated. The inner mold 4, the films 8, 10 and the tubular mold member 6 are heated to increase the temperature of each member,
The inner mold 4 and the tubular mold member 6 expand according to their respective thermal expansion coefficients. The films 8, 10 begin to soften as the temperature rises. Since the inner mold 4 has a larger coefficient of thermal expansion than the tubular mold member 6, the outer diameter of the inner mold 4 and the tubular mold member 6 increase as the temperature rises.
The dimensional gap of the inner diameter becomes narrower than the initial low temperature state. With the narrowing of the gap between the inner mold and the tubular mold member, the films 8 and 10 sandwiched therebetween are further softened, and both ends of the film are softened by the film, so that the overlapping portion decreases in the circumferential direction of the inner mold 4 as the gap decreases. As they are stretched, the overlapping portions are welded to each other to form a joined state. The thickness of the film is substantially the same as the gap between the inner mold and the tubular mold member, and the step at the overlapped portion is apparently eliminated. Then, films 8, 10
By controlling the heating state at the molding temperature, the thickness of the film is adjusted to be spread over the whole. After the above heating step,
The heating is stopped and the process proceeds to the cooling step.

In the cooling step, the inner mold 4, the tubular films 8 'and 10', and the tubular mold member 6 may be cooled naturally after the heating in the heating step is stopped to reduce the cooling time. May be quenched for In this example, after the above-mentioned heating, it is cooled by immersing it in tap water in a liquid tank as in the cooling step (5). After cooling to a cooling temperature near room temperature, (6) the inner mold 4 is removed from the tubular mold member 6 in the inner mold removing step.
Take out from. At this time, the film is stuck to the outside of the inner mold 4 or the inside of the tubular mold member 6 in a cylindrical shape, and the overlap portion of the first sheet-like film is also cleanly joined.

Next, (7) a step of peeling off from the tubular mold member,
In the end cutting step, the tubular films 8 ′ and 10 ′ are
Alternatively, it is peeled off from the tubular mold member 6 and the end is cut.

Next, a method for manufacturing the tubular film of the present embodiment will be specifically described with reference to FIGS.

In FIG. 2, the material of the tubular mold member 6 is S
The K material, the coefficient of linear expansion is 1.22 × 10 ⁻⁵ (1 / K), and the coefficient of linear expansion of the inner hollow cylinder 4 (material A5056) is 2.4.
It is 4 × 10 ⁻⁵ (1 / K). At room temperature (25 ° C.), the design dimension of the inner diameter of the tubular mold member 6 is 70.000 mm, and the design dimension of the outer diameter of the inner mold is 69.669 mm. The design value of the thickness of the transfer belt is 0.100 mm.

A sheet-like film is wound around the above inner mold and inserted into a tubular mold member.
Heat to about (° C).

As shown in FIG. 4, the axial lengths of the tubular mold member 6 and the inner mold 4 are both 400 mm, and the axial length of the sheet film is 390 mm. Further, thermocouples are attached to the inner end of the tubular mold member and at a position 5 mm from the outer end of the inner mold to measure the temperature during heating.

Here, the equation for calculating the linear expansion (dimensions during heating)
= (Dimension before heating) + (dimension before heating) x (linear expansion coefficient) x
From (heating temperature-temperature before heating), the inner diameter of the tubular mold member 6 is 70.000 + 70.000 × 1.22 × 10 ⁻⁵ ×
(180-25) = 70.132 mm.

The outer diameter of the inner mold 4 is 69.669 + 69.6.
69 × 2.44 × 10 ⁻⁵ × (180-25) = 69.9
32 mm.

At this time, the gap between the tubular mold member 6 and the inner mold 4 is (70.132-69.932) /2=0.100 mm.
Becomes

The state in which the sheet films 8, 10 are wound around the inner mold 4 and inserted into the tubular mold member 6 is as shown in FIG. 2, and the molding temperature is as shown in FIG. 6 is different from the design size, the temperature 180
The gap between the inner mold 4 and the tubular mold member 6 at (° C.) differs from the design dimension thickness of the transfer belt.

As an example, at normal temperature (25 ° C.)
Is 70.005 mm and the actual size of the outer diameter of the inner mold 4 is 69.664 mm, the inner diameter of the tubular mold member 6 when heated to 180 ° C. is 70.005 + 70.00.
5 × 1.22 × 10 ⁻⁵ × (180-25) = 70.13
7 mm.

Similarly, the outer diameter of the inner mold 4 when heated to 180 ° C. is 69.664 + 69.664 × 2.44 × 10 ⁻⁵ ×
(180-25) = 69.927 mm.

At this time, the gap between the tubular mold member 6 and the inner mold 4 is (70.137-69.927) /2=0.105 mm.
Since the thickness is different from the design dimension of the tubular film, the thickness of the formed tubular film is also different from the design dimension.

In this embodiment, even when the actual dimensions of the tubular mold member 6 and the inner mold 4 at room temperature are different from the design dimensions, the gap between the tubular mold member and the inner mold at the molding temperature is determined by the design of the tubular film. Provided is a method for manufacturing a tubular film in which the thickness after molding is the same as the designed size by making the thickness the same as the size. Next, this method will be specifically described.
In the present embodiment, in addition to the tubular film manufacturing process shown in FIG. 1, as shown in the block diagram of FIG. A step of measuring the inner diameter of the mold is provided. Also, a terminal 202 for managing and controlling the molding process is provided, and a molding temperature calculating unit 20 for calculating a temperature (molding temperature) in which a gap between the inner mold and the tubular mold member becomes a design value of the film thickness.
3 are provided.

Further, as shown in FIG. 4, as a temperature measuring device 204 for heating the entire inner mold, the tubular mold member, and the forming mold of the sheet-like film in the heating section 205 (electric furnace), the tubular mold member is constituted by a thermocouple. Measuring the inner peripheral surface of the inner mold and the outer peripheral surface temperature of the inner mold,
When the temperature of the molding die reaches the molding temperature at the management / control terminal 202, a command is issued to the heating unit 205 (electric furnace) to stop heating.

Dimension measuring unit 201, management / control terminal 20
2. The heating unit 205 is connected as shown in the block diagram of FIG. 6, and the operator measures the actual dimensions of the inner diameter of the inner mold and the inner diameter of the tubular mold member at room temperature by the dimension measuring unit 201, and manages and measures them.
A numerical value is input to the control terminal 202. Based on the outer diameter of the inner mold and the actual dimensions of the inner diameter of the tubular mold member, a temperature at which the gap between the inner mold and the tubular mold member becomes the design value of the film thickness in the management / control terminal 202 is determined by the molding temperature calculation unit 203. Is calculated by During heating, the temperature of the inner and tubular mold members is measured by the temperature measuring device 204 and transmitted to the management / control terminal 202. The management / control terminal 202 issues a command to the heating unit 205 (electric furnace) to stop heating when the surface temperatures of the outer diameter of the inner mold and the inner diameter of the outer mold reach the calculated temperatures, and shifts to the cooling step. I am trying to do it.

A method of calculating the molding temperature from the actual dimensions of the outer diameter of the inner mold and the inner diameter of the tubular mold member at normal temperature will be described below.

The inner diameter A of the tubular mold member at room temperature T1, the outer diameter B of the inner mold, the molding temperature T2, the inner diameter A 'of the tubular mold member at the molding temperature, the outer diameter B' of the inner mold, and the wire of the tubular mold member. The expansion coefficient is α
A, the coefficient of linear expansion of the inner mold is αB. Also, assuming that the design value of the thickness of the tubular film is t, a linear expansion calculation formula (dimension before heating) = (dimension before heating) + (dimension before heating) × (linear expansion coefficient) × (temperature before heating / temperature before heating) A ′ = A + A × αA × (T2−T1) (1) B ′ = B + B × αB × (T2−T1) (2)

Since the gap between the tubular mold member and the inner mold at the molding temperature T2 is t, (A'-B ') / 2 = t (3) Next, the following equation (1) and (2) Solving the equation (3) for T2 gives: T2 = {2 × t− (AB)} / (A × αA−B × αB) + T1 (4)

By substituting numerical values for A, B, αA, αB, and t in equation (4), even when the inner diameter of the tubular mold member and the outer diameter of the inner mold are different from the design values, the thickness of the tubular film can be adjusted to the design values. It is possible to obtain a molding temperature that can be molded in the same manner.

Actually, A, B, αA, αB, t in the equation (4)
A = 70.005 mm
B = 69.664 mm, αA = 1.22 × 10 ⁻⁵ (1 /
K), αB = 2.44 × 10 ⁻⁵ (1 / K), t = 0.1
A molding temperature T2 = 191.7 ° C. is obtained from 00 mm.

Actually, when molding was performed 20 times at a molding temperature of 192 ° C. with the combination of the tubular mold member and the inner mold having the above dimensions, the thickness of the film after molding was 0.101 m at maximum.
m, the minimum was 0.099 mm, and the average value was 0.100 mm.

Finally, the tubular film manufactured by the tubular film manufacturing apparatus according to the present embodiment is used as a transfer belt of a copying machine, a printer and the like.

In FIG. 7, 8 'and 10' are transfer belts, 101 is a charging drum, 102 is a transfer drum, 103
Is a developing roller, 104 is a transfer / transport roller, 105
Is copy paper, 106 is toner, and the transfer belt 8 ',
Reference numeral 10 ′ is applied to a transfer / transport roller 104. First, the transfer drum 102 is charged by the charging drum 101.
Is applied with the voltage of the image. Next, the developing roller 103
Accordingly, the toner is supplied to the transfer drum 102, and the toner is transferred in the form of an image. Here, the transfer belts 8 ', 1
The copy paper 105 is supplied by 0 ', and the toner is transferred from the transfer drum 102 to the copy paper. The copy paper to which the toner has been transferred is transported to a fixing unit (not shown). When a transfer belt manufactured using the molding method of the present embodiment was used in this image forming process,
It was possible to form an image with less unevenness than the transfer belt using the conventional molding method.

(Other Embodiments) In the above embodiment, the means for measuring the inner diameter of the tubular mold member and the outer diameter of the cylindrical member at normal temperature, and the measured inner diameter of the tubular mold member and the outer diameter of the cylindrical member, The inner mold has means for calculating the temperature at which the gap between the tubular mold members is equal to the design dimension of the thickness of the tubular film, and calculates the forming temperature from the inner diameter of the tubular mold member at room temperature and the outer diameter of the cylindrical member at room temperature. While heating the mold member and the columnar member, the film is provided with a means for measuring the temperature of the tubular mold member and the columnar member, and when the calculated molding temperature is reached, the heating is terminated. The thickness of the tubular film is designed to be the same as the design dimension. Here, in the present embodiment, the time (forming time) when the entire tubular mold member, the cylindrical member, and the film are heated from room temperature to the molding temperature is constant if the tubular mold member and the cylindrical member used are the same. Therefore, the history of the temperature and the time during which the tubular mold member and the columnar member are being heated are measured, and the time from the start of heating until the molding temperature is reached is defined as the molding time.

From the next molding, only the time from the start of heating may be measured, and the heating may be terminated when this time reaches the molding time.

FIG. 8 shows the heating temperature and the molding time depending on the dimensions of the inner mold and the tubular mold member.

As shown in FIG. 8, the tubular mold member 1 (inner diameter 70.
000 mm) and an inner mold 1 (outer diameter 69.669 mm) in combination, a heating time of 90 minutes and a forming temperature of 180
Reach ° C. Further, the tubular mold member 2 (inner diameter of 70.005 m
m) and the inner mold 2 (outer diameter 69.664 mm) in combination, the heating time was 105 minutes and the molding temperature was 191.7.
Reach ° C.

Actually, when molding was performed 20 times with a combination of the tubular mold member 2 and the inner mold 2 in a molding time of 105 minutes, the film thickness after molding was 0.102 mm at the maximum, 0.099 mm at the minimum, and the average value was 0.101 mm.

Further, a tubular mold member when the molding temperature is reached,
The pressure (forming pressure) generated in the tubular film material between the cylindrical members is constant if the gap between the tubular member and the cylindrical member is constant. The generated pressure may be measured in advance, and the heating may be terminated when the pressure reaches the molding pressure.

In this case, as shown in FIG. 5, a pressure sensor 301 is attached perpendicularly to the outer peripheral surface of the tubular mold member, and the temperature of the tubular mold member and the cylindrical member when heated to the molding temperature and the pressure generated in the tubular film material are measured. The pressure when the temperature is measured and reaches the molding temperature is defined as the molding pressure. As shown in FIG. 4, the axial lengths of the tubular mold member and the inner mold are both 400 mm, and the axial length of the sheet film is 390 mm. Further, a pressure sensor 301 is provided perpendicularly to the outer peripheral surface at a position 15 mm from the outer peripheral surface side end of the tubular mold member, and the tip of the pressure sensor 301 contacts the inner peripheral surface of the tubular mold member. In this manner, the temperature of the tubular mold member and the inner mold and the pressure generated in the tubular film material are measured. Molding is actually performed at a molding temperature of 180 ° C. using the inner mold 1 and the tubular mold member 1,
When the molding pressure was measured, it was about 600 g / mm ² .
From the next molding, only the temperature of the tubular mold member and the inner mold at the time of heating and the pressure generated in the tubular film material may be measured, and the heating may be terminated when the pressure reaches the molding pressure.

Actually, when molding was performed 20 times with a combination of the tubular mold member 1 and the inner mold 1 at a molding pressure of about 600 g / mm ² , the thickness of the film after the molding was a maximum of 0.102.
mm, the minimum was 0.098 mm, and the average value was 0.100 mm.

As described above, according to the above-described embodiment, (1) even if the actual dimensions of the tubular mold member and the inner mold are different from the design dimensions, molding is performed from the actual dimensions of the tubular mold member and the inner mold. Calculate the temperature, the mold surface temperature during heating, the outer diameter of the inner mold at room temperature, in order to mold the thickness of the tubular film to the design dimensions,
Means for measuring the actual dimensions of the inner diameter of the outer mold, means for calculating the temperature such that the gap between the inner mold and the outer mold in the heated state becomes the design value of the film thickness, and the inner mold and the temperature of the tubular mold member Provision of means for measuring, the inner mold, the heating is stopped when the surface temperature of the tubular mold member reaches the calculated temperature, the gap between the inner mold and the outer mold at the molding temperature becomes the design value of the film thickness. Like that. (2) Also, by measuring the time (molding time) at which the mold surface temperature during heating reaches the molding temperature, it is not necessary to measure the temperature from the next molding, and the heating time has reached the molding time. The heating can be stopped at that point, and the gap between the inner mold and the outer mold during the molding time is set to the design value of the film thickness. (3) Also, by measuring the pressure (molding pressure) generated in the tubular film material between the tubular mold member and the inner mold when the mold surface temperature at the time of heating reaches the molding temperature, the next molding can be performed. It is not necessary to measure the temperature, the heating can be stopped when the pressure reaches the molding pressure, and the gap between the inner mold and the outer mold at the molding pressure is set to the design value of the film thickness. .

[0056]

As described above, according to the present invention,
The gap between the tubular mold member and the cylindrical member at the molding temperature is always kept constant, and the thickness of the tubular film after molding can be set to the thickness of the design dimensions.

[Brief description of the drawings]

FIG. 1 is a view showing a manufacturing process of a tubular film.

FIG. 2 is a state diagram showing a state where a sheet-like film is wound around an inner mold at room temperature and inserted into a tubular mold member.

FIG. 3 is a state diagram showing a state of an inner mold, a film, and a tubular mold member at a molding temperature.

FIG. 4 is a view showing a state in which a thermocouple is attached to an inner mold and a tubular mold member.

FIG. 5 is a diagram showing a state where a pressure sensor is attached to a tubular mold member.

FIG. 6 is a block diagram illustrating a relationship among a dimension measurement unit, a molding temperature calculation unit, and a temperature measurement unit.

FIG. 7 is a view showing a use form of a tubular film.

FIG. 8 is a diagram showing a heating temperature and a molding time depending on dimensions of an inner mold and a tubular mold member.

[Explanation of symbols]

 2 Roll of thermoplastic resin film 4 Inner die 6 Tubular die member 8,10 Sheet-like film 8 ′, 10 ′ Tubular film 12 Cooling unit 101 Charging drum 102 Transfer drum 103 Developing roller 104 Transfer, transport roller 105 Copy paper 106 Toner 201 Dimension measurement unit 202 Management / control terminal 203 Molding temperature calculation unit 204 Temperature measurement device (thermocouple) 205 Heating unit 301 Pressure sensor

Claims (6)

[Claims] 1. A thermoplastic resin sheet-like film wound in a roll shape around an inner mold is inserted into a tubular mold member having an inner diameter slightly larger than the outer diameter of the inner mold, and subjected to heat molding. In the apparatus for manufacturing a tubular film, a dimension measuring means for measuring an inner diameter of the tubular mold member and an outer diameter of the inner mold at normal temperature; and an inner diameter dimension of the tubular mold member and an outer diameter dimension of the inner mold at normal temperature. A calculating means for calculating a heating temperature such that a gap between the tubular mold member and the inner mold becomes a predetermined gap, and a temperature measuring means for measuring the temperature of the tubular mold member and the inner mold. An apparatus for producing a tubular film, comprising: 2. The tubular film manufacturing apparatus according to claim 1, further comprising means for measuring the history of the temperature and elapsed time of the tubular mold member and the inner mold. 3. The tubular film according to claim 1, further comprising means for measuring a history of a pressure and an elapsed time generated in the tubular film material between the tubular mold member and the inner mold. manufacturing device. 4. A sheet-like film of a thermoplastic resin wound in a roll shape around an inner mold is inserted into a tubular mold member having an inner diameter slightly larger than the outer diameter of the inner mold, and heat molding is performed. In the method for manufacturing a tubular film, a dimension measuring step of measuring an inner diameter of the tubular mold member and an outer diameter of the inner mold at normal temperature, and an inner diameter dimension of the tubular mold member and an outer diameter dimension of the inner mold at normal temperature A calculating step of calculating a heating temperature such that a gap between the tubular mold member and the inner mold becomes a predetermined gap, and a temperature measuring step of measuring a temperature of the tubular mold member and the inner mold. A method for producing a tubular film, comprising: when at least the temperature measured in the temperature measuring step reaches the temperature calculated in the calculating step, stopping at least the heating accompanied by the temperature rise. 5. The method for producing a tubular film according to claim 4, further comprising a step of measuring the history of the temperature and elapsed time of the tubular mold member and the inner mold. 6. The tubular film according to claim 4, further comprising a step of measuring a history of a pressure and an elapsed time generated in the tubular film material between the tubular mold member and the inner mold. Production method.