JPS6059128B2 - Film positioning method for transfer molding equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field The present invention relates to a method for positioning a film in a transfer molding apparatus.

In other words, a transfer molding device is a device that inserts a plastic transfer film between the molds of an injection molding machine and transfers a pattern previously printed on the transfer film to the molded product at the same time as molding. The present invention relates to a method for accurately positioning a transfer film with respect to a molding part during molding. (0) Prior Art Film positioning in a conventional transfer molding apparatus was performed as follows.

That is, the transfer film is sent out from the coil by a feeding roll, and the transfer film is positioned so that the pattern is at a predetermined position between the feeding roll and the tension roll. The length has been controlled by using a timer to control the operating time of the motor that drives the feed roll, or by reading marks on the transfer film using an optical sensor. However, when positioning the transfer film using such a conventional method, it is unavoidable that an error of several millimeters occurs in the position of the pattern on the transfer film. For this reason, it has not been possible to obtain a transfer molded product in which the position of the design relative to the molded product is precisely defined. (c) Purpose of the Invention The object of the present invention is to provide a film positioning method that can position a pattern with precision in micrometers and can obtain a precise transfer molded product.

(d) Structure of the Invention The first invention according to the present application switches the film feeding speed in two stages when positioning the film in the longitudinal direction, and feeds the transfer film at a very slow speed just before stopping. Improved directional positioning accuracy and improved width direction A
, After returning to the initial position, the positioning accuracy in the width direction is improved by moving it to a predetermined position in the width direction.

In addition to the effects of the first invention, the second invention according to the present application makes it possible to align the center of the pattern with the center position of the molding part even when the transfer film is tilted. There is.

For this reason, two width direction sensors are provided, and after detecting the width direction mark on the transfer film, they are returned to the initial position, and the transfer film is moved in the width direction again, so that the width direction mark is detected. When the transfer film reaches the intermediate position between both sensors, the movement of the transfer film in the width direction is stopped. The third invention according to the present application further improves positioning accuracy by detecting the inclination of the transfer film in the same manner as the second invention and moving the guide roller so as to eliminate the inclination.

(e) Examples Examples of the present invention will now be described with reference to FIGS. 1 to 6 of the accompanying drawings.

(Example of the first invention) The transfer molding apparatus is shown in FIGS. 1 and 2.

A movable platen 34 is guided by tie bars 33 attached to a fixed platen 32 fixed on a frame 31.
The movable platen 34 is movably supported on the frame 31 by rollers 35. A fixed mold 36 is attached to the fixed platen 32. The fixed mold 36 has a convex portion 36'' on its parting surface side. Molten resin can be injected into the fixed mold 36 from an injection nozzle 39. A movable mold 40 is attached to the movable platen 34. The movable mold 40 has a concave portion 4'' corresponding to the convex portion 36'' of the fixed mold 36.
The fixed mold 36 has a guide pin 43 that fits into a bush 42 (see FIG. 2) of the movable mold 40 when the mold is closed.
A frame 60 is attached to the movable platen 34 so as to be movable in the horizontal direction. That is, the frame 60 is guided by four guides 62 with respect to two guide rails 61 attached to the movable platen 34. guide 62
A direct-acting slide bearing is used. The frame 60 can be moved horizontally by a widthwise moving device 93 shown in FIG. That is, the motor 63 of the widthwise moving device 93 is connected to a ball screw 67 by a six-pulley belt 65 and a pulley 66, and the ball screw 67 is engaged with a nut attached to the frame 60. Therefore, by rotating the motor 63, the ball screw 67 is rotated, thereby moving the frame 60 in the horizontal direction. The frame 60 includes rollers that support the coil 69 and feeding rolls 72 and 7 that guide the transfer film 71 unwound from the coil 69.
3, and tension rolls 74 and 75 are provided. The feed roll 73 is driven by the motor 76 of the longitudinal displacement device 94. A dancer roll 77 is provided in front of the tension rolls 74 and 75, thereby applying a constant tension to the transfer film 71. The frame 60 further includes guide rolls 78, 79 and a guide bar 80.
, 81 are provided, thereby making the transfer film 71 more stable. Guide roll 7
8 and 79 are provided with collars 78a and 79a, respectively, which prevent the transfer film 71 from moving in the width direction. The movable mold 40 is provided with a width direction sensor 82,
The frame 60 also includes longitudinal sensors 83a and 83.
b is provided. The width direction sensor 82 and the longitudinal direction sensors 83a, 83b are optical sensors that detect the positions of the width direction mark 84 and the longitudinal direction mark 85 provided in advance on the transfer film 71, respectively. The longitudinal direction sensors 83a and 84b detect the longitudinal position of the transfer film 71. Note that the longitudinal direction sensor 83a is provided at a position slightly upstream of the longitudinal direction sensor 83b. In addition, each sensor 8
The mounting positions of 2, 83a and 83b can be finely adjusted.
Next, a film positioning method in this transfer molding apparatus will be explained.

First, the feeding roll 73 is rotated by operating the motor 76, and the transfer film 71 is unwound from the coil 69.

In addition, since the motor 76 is rotated at high speed at this time, the feeding speed of the transfer film 71 is high. The high speed rotation of the motor 76 is maintained until the longitudinal direction mark 85 on the transfer film 71 is detected by the longitudinal direction sensor 83a. The transfer film 71 is connected to the motor 76
tension rolls 74 and 75 while being pulled out by the rotation of
does not rotate. The dancer roll 77 is in an upper position when the transfer film 71 starts to be unwound, and moves downward together with the unwinding of the transfer film 71. This lowering of the dancer roll 77 applies a certain tensile force to the transfer film 71. The transfer film 71 is fed a predetermined length, and the longitudinal direction sensor 83a detects the transfer film 7.
When the longitudinal mark 85 on 1 is detected, the mofuta 76
The rotational speed of the transfer film 71 is switched to the low speed side.
The feed speed becomes very slow (for example, at low speed, the increase is about 1' at high speed). In this way, the transfer film 71
is fed at a low speed, and when the longitudinal direction sensor 83b located slightly below the longitudinal direction sensor 83a detects the longitudinal direction mark 85, the motor 76 is stopped and the feeding of the transfer film 71 is stopped. Transfer film 71
Immediately before the feeding of the transfer film 71 is stopped, the feeding speed of the transfer film 71 is extremely slow as described above, so the positional accuracy of the transfer film 71 when it stops is very high, with an accuracy of micrometers. can be controlled. As the motor 76, a servo motor is used to stabilize the rotation speed, and the rotation speed is controlled by feedback control using a tacho generator or an encoder. In this embodiment, two longitudinal direction sensors 83a and 83b are provided to change the feeding speed of the transfer film 71 and detect one longitudinal mark 85 on the transfer film 71. Even if the number of longitudinal direction sensors is one and two longitudinal direction marks are provided on the transfer film 71, the same operation as described above can be performed. After positioning in the longitudinal direction as described above, positioning in the film width direction is performed.

In the previous cycle, the film was positioned accurately in the width direction, but in this cycle, the transfer film 71 was fed in the longitudinal direction, so errors in the parallelism of the roll, deformation of the transfer film, printing errors, etc. For this reason, the position cannot be said to be accurate after being fed in the longitudinal direction. First, the motor 63 is activated to move the frame 60 to the left in FIG. 2 and stop it at a predetermined initial position. The initial position is determined by the width direction sensor 82.
The width direction mark 84 on the film 71 is set at a position where it is not detected. The initial position is set by an adjustable limit switch (not shown). In this embodiment, the pattern 91 on the transfer film 71 is located at the molding position 90. The initial position is set at a position moved several millimeters to the left in FIG.
After moving the frame 60 to the initial position, the motor 63
begins a reversal, moving frame 60 to the right in FIG. By doing this, the transfer film 71
moves to the right to a predetermined position, the width direction sensor 8
2, the width direction mark 84 on the transfer film 71 is detected. At the same time as the mark 84 is detected, the motor 63 stops, and the positioning of the transfer film 71 in the width direction is completed. Note that a servo motor is used as the motor 63, and the first movement to the initial position (that is, the movement to the left in FIG. 2) is performed at a relatively high speed, and the subsequent movement to the right is performed at a relatively high speed. Do this at a relatively slow speed. By doing so, positioning in the width direction can be performed with sufficiently high precision in a short time. When the film has been positioned in the longitudinal and width directions as described above, the movable platen 34 moves to close the mold, and then the molten resin is injected from the injection nozzle 39, simultaneously with the molding. The pattern 91 on the transfer film 71 is transferred.

During this time, the tension rolls 74 and 75 are rotated by a drive device (not shown), and the dancer roll 77, which was in the lower position, is pulled up to the upper position, and the transfer film 71 is wound up. . After cooling the molded product, the mold is opened and the molded product is taken out. This completes one cycle of operation. (Embodiment of the second invention) Figures 3 and 4 show an embodiment of the second invention according to the present application.

This embodiment of the second invention allows the pattern 91 to be accurately positioned at the molding position even if the transfer film 71 is tilted. In the transfer molding apparatus shown in FIGS. 1 and 2, collars 78a and 79a are provided on the guide rolls 78 and 79, respectively, to restrict the movement of the transfer film 71 in the width direction. Since some gaps are provided in consideration of this, it is unavoidable that the transfer film 71 will tilt to some extent. When the transfer film 71 is tilted, when the width direction sensor 82 above the molding section detects that the width direction mark 84 of the transfer film 71 has come to a predetermined position, the center position of the molding section and the pattern center position are determined. An error based on the slope occurs in between. That is, if the inclination angle of the transfer film 71 is α, and the distance between the center of the molding part and the width direction sensor 82 is l, then l-Si
An error in the width direction occurs by nα. The second invention aims to correct this error. FIG. 3 corresponds to FIG. 2 of the embodiment of the first invention, and only the parts necessary for explanation are shown, but the configuration of the other parts is the same as that shown in FIGS. 1 and 2. The same is true.

In this embodiment, two width direction sensors are provided, namely an upstream width direction sensor 82 and a downstream width direction sensor 86. The earth flow side width direction sensor 82 and the downstream side width direction sensor 86 detect water passing through the center of the mold forming part.
They are placed symmetrically with respect to the plane. The other configurations are the same as the transfer molding apparatus of the first embodiment described above. Next, the film positioning method of this embodiment will be explained.

First, longitudinal positioning is performed, which is exactly the same as in the first embodiment of the invention described above. The frame 60 then returns to its initial position at a relatively fast speed and then begins to move to the right in FIG. When the transfer film 71 moves a predetermined distance, the transfer film 7
1, there is always some inclination, so either the upstream width direction sensor 82 or the downstream width direction sensor 86 detects the width direction mark 84 first. Next, after a slight movement, the other width direction sensor detects the width direction mark 84. As described above, the two width direction sensors 82 and 86 sequentially detect the mark 84, but the detection time difference T between the two width direction sensors 82 and 86 is stored in a control device (not shown). Note that since the moving speed of frame 60 is constant, detecting the time difference T can be done at frame 6.
This is equivalent to detecting a movement distance difference of 0. When the two width direction sensors 82 and 86 detect the mark 84,
The frame 60 returns to its initial position again at high speed.

The frame 60 then begins to move to the right in FIG. 3 again. The movement speed at that time is the same as the movement speed during the previous movement to the right. If the upstream width direction sensor 82 had first detected the width direction mark 84 during the previous rightward movement, then the width direction mark 84 was first detected by the upstream width direction sensor 82 during this rightward movement as well. be done. After the upstream width direction sensor 82 detects the mark 84, the movement of the transfer film 71 is continued for T/2 hours and then stopped. By doing this, mark 8
4 is at an intermediate position between the upstream width direction sensor 82 and the downstream width direction sensor 86, the transfer film 71 is stopped, and the pattern 91 is accurately placed in the molding part regardless of the inclination of the transfer film 71. It will be positioned at the center of 90. The above control is shown in FIG. 4 as a flowchart. (Embodiment of the third invention) Next, an embodiment of the third invention according to the present application will be described.

The third invention aims to eliminate the inclination of the transfer film 71. FIG. 5 shows a transfer molding device. This transfer molding device is similar to the transfer molding device of the second invention described above, except that the guide roll 79 can adjust its axial position. FIG. 6 shows an enlarged view of the guide roll 79. The guide roll 79 is rotatably supported via bearings 102 and 103 on a shaft 101 that does not rotate with respect to the frame 60 but is attached to be movable in the axial direction. A threaded portion at the right end of the shaft 101 in FIG. 6 is engaged with an internal thread of a shaft 104 rotatably supported on the frame 60. Therefore, by rotating the shaft 104, the shaft 101 can be moved laterally in FIG. 6. The shaft 104 is connected to a motor 109 that constitutes a guide roll moving device 95 via a pulley 105, a belt 106, a pulley 107, and a reduction gear 10.8. After all, by rotating the motor 109, the guide roll 79 can be moved in the axial direction. The longitudinal positioning of the transfer film 71 in the case of the third invention is performed in the same manner as in the first and second inventions described above.

Next, as in the case of the second invention, the frame 60 moves at high speed to the initial position, then moves to the right in FIG. 5, and the upstream width direction sensors 82 and 86 sequentially detect the width direction mark 84. After taking it out, the time difference (or movement distance difference) is memorized and it returns to the initial position again. After returning to the initial position, the motor 109 is rotated by a predetermined amount in a predetermined direction based on the stored time difference (or movement distance difference). The rotation direction of the motor 109 is determined by, for example, the upstream side 7 width direction sensor 8.
2 detects the width direction mark 84 first, the direction of rotation is to move the guide roll 79 to the right in FIG. 5, and conversely, the downstream width direction sensor 86 detects the width direction mark 84 first. In this case, the direction of rotation is to move the guide roll 79 to the left in FIG. Further, the moving distance of the guide roll 79 is set to be enough to eliminate the difference in width direction mark detection time (or movement distance difference) between the upstream width direction sensor 82 and the downstream width direction sensor 86. This moving distance is easily calculated based on the ratio of the distance between the upstream width direction sensor 82 and the downstream width direction sensor 86 and the distance between the guide rolls 78 and 79. The guide roll 79 is moved as described above, and both width direction sensors 8
After aligning the transfer film 71 parallel to the line connecting the lines 2 and 86, the frame 60 moves to the right in FIG. Stop when detected. By positioning the transfer film 71 as described above, the longitudinal position, width direction position, and inclination of the pattern 91 of the transfer film 71 can be accurately adjusted with respect to the molding part 90 of the mold. Become. Therefore, transfer molding can be performed with extremely high positional accuracy. In the above embodiment, the guide roll moving device is provided on the guide roll 79 on the downstream side, but it may also be provided on the guide roll 78 on the upstream side.

In addition, although the above explanation was all about the case where the transfer film 71 is moved from the top to the bottom, the present invention can be applied even when it is moved in the opposite direction, when it is moved in the horizontal direction, etc. is clear. (F) Effects of the Invention As explained above, according to the first invention, a transfer film is sandwiched between a fixed mold and a movable mold, and the design on the transfer film is transferred to a molded product at the same time as injection molding. The device includes a frame movable in the axial direction of the transfer film, a width direction moving device capable of moving the frame to a predetermined position, and a feeding roll and a tension roll provided on the frame. , a film positioning method in a transfer molding apparatus having a longitudinal direction moving device for rotating a feed roll, and a longitudinal direction sensor and a width direction sensor capable of detecting longitudinal and width direction marks on a transfer film, respectively. , the longitudinal direction moving device is operated to feed the transfer film at high speed to a predetermined position immediately before the longitudinal stop position, and when the longitudinal direction sensor detects that the transfer film has reached the predetermined position, the feeding speed is reduced. When the longitudinal direction sensor detects that the transfer film has reached the longitudinal stop position, the longitudinal movement device is stopped, and the width direction movement device is then activated to return the frame to the initial position. When the width direction sensor detects the width direction mark on the transfer film, the width direction moving device is stopped to position the transfer film. The pattern on the film can be precisely and quickly aligned with the molding part, and the reproducibility of alignment is also improved.

Furthermore, since the order of each operation is determined, the control device can be a simple sequence control device. According to a second aspect of the present invention, there is provided a transfer molding device for sandwiching a transfer film between a fixed mold and a movable mold and transferring a pattern on the transfer film to a molded product at the same time as injection molding, the transfer film having a width of a frame movable in the direction, a widthwise moving device capable of moving the frame to a predetermined position, a feed roll and a tension roll provided on the frame, and a longitudinal movement that rotates the feed roll. A device, a longitudinal sensor capable of detecting longitudinal marks on the transfer film, and two sensors on the upstream and downstream sides of the film feeding direction of the mold forming section.
In a film positioning method in a transfer molding device having a width direction sensor installed at a location and capable of detecting width direction marks on the transfer film, a longitudinal direction moving device is operated to move the transfer film just before the longitudinal stop position. The transfer film is fed at a high speed to a predetermined position, and when the longitudinal sensor detects that the transfer film has reached the predetermined position, the feeding speed is switched to a low speed, and the longitudinal sensor detects that the transfer film has reached the longitudinal stop position. When the longitudinal movement device is detected by The frame is moved until the direction sensor detects the width direction mark on the transfer film, and the width direction mark detection time difference or movement distance difference between both sensors is memorized, and then the frame is returned to the initial position, and then the frame is moved again. Since the transfer film is positioned by stopping the width direction moving device when it reaches a predetermined position calculated based on the width direction mark detection time difference or movement distance difference stored during the previous movement, the effect of the first invention is achieved. In addition, even when the transfer film is tilted, there is an effect that the center of the pattern can be accurately aligned with the center of the molding part.

Furthermore, according to a third aspect of the present invention, there is provided a transfer molding device which inserts a transfer film between a fixed mold and a movable mold and transfers a design on the transfer film to a molded product at the same time as injection molding, in the width direction of the transfer film. A movable frame, a widthwise moving device capable of moving the frame to a predetermined position, a feeding roll and a tension roll provided on the frame, and a longitudinal moving device rotating the feeding roll; A longitudinal sensor that can detect the longitudinal mark on the transfer film, and a width that can detect the width mark on the transfer film, which is installed at two locations on the upstream and downstream sides of the film feeding direction of the mold forming section. In a method for positioning a film in a transfer molding apparatus having a direction sensor and a guide roll whose width direction position can be adjusted by a guide roll moving device provided on the upstream side or downstream side of the molding part of the frame,
The longitudinal direction moving device is operated to feed the transfer film at high speed to a predetermined position just before the longitudinal stop position, and when the longitudinal direction sensor detects that the predetermined position has been reached, the feed speed is switched to a low speed. When the longitudinal direction sensor detects that the transfer film has reached the longitudinal stop position, the longitudinal direction moving device is stopped, and the width direction moving device is then activated to return the frame to the initial position. Start moving the frame from this position, move the frame until both the upstream and downstream width direction sensors detect the width direction mark on the transfer film, and calculate the width direction mark detection time difference or movement distance difference between both sensors. Then, the guide roll moving device is operated by a predetermined amount in the direction of eliminating the inclination of the transfer film by calculation based on the difference in detection time or movement distance in the width direction of both sensors, and then Since the transfer film is positioned by moving the frame again and stopping the width direction moving device when both sensors detect the width direction mark, in addition to the effect of the first invention, the inclination of the transfer film is corrected. Therefore, it is possible to perform transfer molding in which the positions and orientations of the patterns are accurately matched.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing a transfer molding device implementing the first invention, Fig. 2 is a cross-sectional view of the transfer molding device shown in Fig. 1 taken along line 1, and Fig. 3 is a transfer molding device implementing the second invention. FIG. 4 is a diagram showing a control flowchart of the second invention; FIG. 5 is a diagram showing a transfer molding apparatus implementing the third invention; FIG.
The figure is an enlarged view of the guide roll of the transfer molding apparatus shown in FIG. 5. 31...Frame, 32...Fixed plate, 3
3... Tie bar, 34... Movable plate, 35...
...Roller, 36...Fixed type, 39...
...Injection nozzle, 40...Movable type, 42...Bush, 43...Guide pin, 60...
・Frame, 61... Guide rail, 62...
...Guide, 63...Motor, 64...
・Pulley, 65...Belt, 66...Pulley, 67...Ball screw, 69...Coil, 71
...Transfer film, 72,73...Feed roll, 74,75...Tension roll, 76...
...Motor, 77...Dancer roll, 78
, 79... Guide roll, 80, 81...
・Guide bar, 82... Width direction sensor, 83
a, 83b...Longitudinal direction sensor, 90h...
...Molding part, 91...Design, 93...
- Width direction moving device, 94... Longitudinal direction moving device, 95... Guide roll moving device.

Claims (1)

[Claims] 1. A transfer molding device that inserts a transfer film between a fixed mold and a movable mold and transfers the design on the transfer film to a molded product at the same time as injection molding, in the width direction of the transfer film. A movable frame, a widthwise moving device capable of moving the frame to a predetermined position, a feeding roll and a tension roll provided on the frame, and a longitudinal moving device rotating the feeding roll; In a method for positioning a film in a transfer molding apparatus having a longitudinal direction sensor and a width direction sensor capable of detecting marks on a transfer film in the longitudinal direction and width direction, respectively, the longitudinal direction moving device is operated to move the transfer film in the longitudinal direction. The transfer film is fed at high speed to a predetermined position immediately before the stop position, and when the longitudinal direction sensor detects that the transfer film has reached the predetermined position, the feed speed is switched to a low speed and the transfer film reaches the stop position in the longitudinal direction. is detected by the longitudinal direction sensor, the longitudinal direction moving device is stopped, then the width direction moving device is activated to return the frame to the initial position, and the frame starts moving from the initial position, and when the width direction sensor detects A method for positioning a film in a transfer molding apparatus, characterized in that the transfer film is positioned by stopping a width direction moving device when a width direction mark on the transfer film is detected. 2. A transfer molding device that inserts a transfer film between a fixed mold and a movable mold and transfers the design on the transfer film to a molded product at the same time as injection molding, the frame movable in the width direction of the transfer film; A width direction moving device capable of moving the frame to a predetermined position, a feeding roll and a tension roll provided on the frame, a longitudinal direction moving device that rotates the feeding roll, and a longitudinal direction movement device on the transfer film. A transfer device having a longitudinal direction sensor capable of detecting a direction mark, and a width direction sensor capable of detecting a width direction mark on a transfer film, which is provided at two locations on the upstream side and downstream side of the film feeding direction of the mold forming section. In a film positioning method in a forming device, a longitudinal direction moving device is operated to feed the transfer film at high speed to a predetermined position just before the longitudinal stop position, and a longitudinal direction sensor detects when the transfer film has reached the predetermined position. When this occurs, the feed speed is switched to a low speed
When the longitudinal direction sensor detects that the transfer film has reached the longitudinal stop position, the longitudinal direction moving device is stopped, and then the width direction moving device is activated to return the frame to the initial position, and the frame is returned to the initial position. Start moving the frame from , move the frame until both the upstream and downstream width direction sensors detect the width direction mark on the transfer film, and memorize the width direction mark detection time difference or movement distance difference between both sensors. Then, the frame is moved again and the width direction moving device is stopped when it reaches a predetermined position calculated based on the width direction mark detection time difference or movement distance difference stored during the previous movement. 1. A method for positioning a film in a transfer molding apparatus, comprising positioning a film for transfer by using a method for positioning a transfer film. 3. A transfer molding device that inserts a transfer film between a fixed mold and a movable mold and transfers the design on the transfer film to a molded product at the same time as injection molding, the frame movable in the width direction of the transfer film; A width direction moving device capable of moving the frame to a predetermined position, a feeding roll and a tension roll provided on the frame, a longitudinal direction moving device that rotates the feeding roll, and a longitudinal direction movement device on the transfer film. A longitudinal direction sensor that can detect direction marks, a width direction sensor that can detect width direction marks on the transfer film, which are installed at two locations on the upstream and downstream sides of the film feeding direction of the mold forming section, and a frame molding sensor. In a method for positioning a film in a transfer molding apparatus, the transfer molding apparatus includes a guide roll provided on the upstream side or the downstream side of the section and whose width direction position can be adjusted by a guide roll moving device. The transfer film is fed at a high speed to a predetermined position just before the longitudinal stop position, and when the longitudinal sensor detects that the transfer film has reached the predetermined position, the feed speed is switched to a low speed and the transfer film reaches the longitudinal stop position. When this is detected by the longitudinal sensor, the longitudinal movement device is stopped, and the width direction movement device is then activated to return the frame to the initial position, start moving the frame from the initial position, and move the upstream and The frame is moved until both width direction sensors on the downstream side detect the width direction mark on the transfer film, and after storing the width direction mark detection time difference or movement distance difference of both sensors, it is returned to the initial position, and then The guide roll moving device is operated by a predetermined amount in the direction to eliminate the inclination of the transfer film by calculation based on the widthwise mark detection time difference or movement distance difference between both sensors, and then the frame is moved again so that both sensors detect the widthwise mark. 1. A method for positioning a film in a transfer molding apparatus, characterized in that the transfer film is positioned by stopping a width direction moving device when the transfer film is moved.