JPH032062B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a transfer molding device.
A transfer molding device is a device in which a plastic transfer film is inserted between the molds of an injection molding machine, and a pattern previously printed on the transfer film is transferred to a molded product at the same time as molding.

(b) Prior Art There is a conventional transfer molding apparatus as shown in FIGS. 1 and 2, for example. The pattern 22 on the transfer film 20 is transferred between the movable die 14 attached to the movable plate 12 and the fixed die 18 attached to the fixed plate 16. The transfer film 20 is positioned by a film positioning device 24. That is, the film positioning device 24
The transfer film 20 can be fed in the film longitudinal direction and stopped at a predetermined position, and the film positioning device 24 itself can be moved in the film width direction and stopped at a predetermined position. A longitudinal direction sensor 26 and a width direction sensor 28 for detecting the longitudinal position and width direction position of the transfer film 20, respectively, are attached to a stationary part above the outside of the mold. On the transfer film 20, longitudinal marks 30 arranged at the same pitch as the pattern 22 and continuous width marks 32 are printed. The longitudinal positioning of the transfer film 20 is performed by stopping the feeding of the transfer film 20 when the longitudinal direction sensor 26 detects the longitudinal direction mark 30, and the widthwise positioning of the transfer film 20 is performed by: Width direction sensor 2
This is done by horizontally moving the film positioning device 24 to a position where the width direction mark 32 is detected.

However, in the conventional transfer molding apparatus as described above, the position of the transfer film 20 is detected by the longitudinal direction sensor 26 and the width direction sensor 28, which are arranged far from the center of the mold. If the film 20 is tilted due to heat, even if the longitudinal direction mark 30 and the width direction mark 32 are at the predetermined positions at the positions of the longitudinal direction sensor 26 and the width direction sensor 28, respectively, the center position of the pattern 22 will not be the same. The transfer film 20 could not be accurately positioned because the center position of the transfer film 20 did not coincide with the center position of the mold. Further, if there is a printing error between the pattern 22 on the transfer film 20 and the marks 30 and 32, the error is amplified. Therefore, if the transfer film 20 is tilted with respect to the surface of the mold, or if there is a printing error between the marks 30 and 32 and the pattern 22, the transfer film 20 can be placed in the transfer position accurately. There is a problem that positioning cannot be determined.

By the way, as a transfer press device similar to a transfer molding device, there is one shown in, for example, Japanese Patent Application Laid-Open No. 56-34458. A tape-shaped transfer sheet is provided with a transfer pattern and a position marker placed in the center of the transfer pattern, arranged side by side at appropriate intervals, and an imaging optical system is used to detect the position marker from the diagonal side of the transfer sheet. A photoelectric element detection device with a system is provided. By doing so, the position mark can be detected at the transfer pressing position and the transfer sheet can be positioned. By utilizing this, the problems of the prior art shown in FIGS. 1 and 2 can be solved.

(c) Problems to be Solved by the Invention However, the photoelectric element detection device equipped with an imaging optical system as shown in the above-mentioned Japanese Patent Application Laid-Open No. 56-34458 is large and needs to be located far from the mold. Since the position mark provided on the transfer sheet is detected diagonally from the side with respect to the transfer sheet, it is generally difficult to accurately detect the position mark. Even if accurate positioning is possible, accurate positioning becomes impossible if the distance between the transfer sheet and the mold slightly changes due to vibrations when the transfer sheet is fed. Therefore, if the distance between the transfer sheet and the mold is increased to increase the detection angle of the transfer sheet with respect to the position mark, the distance to move when fixing the transfer sheet to the mold becomes large, making it easy for the position to shift. There is a problem. Furthermore, since the width of the mold is generally about twice the width of the transfer sheet, if the distance between the transfer sheet and the mold is too small, the detection angle of the photoelectric element detection device with respect to the position mark will become small. Another problem is that it becomes virtually impossible to detect the location marker. The present invention aims to solve the above problems.

(d) Means for Solving the Problems The present invention achieves the above object by arranging either or both of a longitudinal direction sensor and a width direction sensor within a mold. That is, the transfer molding apparatus according to the present invention positions the transfer film 58 in the longitudinal direction and the width direction by the film positioning device 52 provided on the mold side of either the fixed mold 44 or the movable mold 46. , a transfer film 58 is sandwiched between the fixed mold 44 and the movable mold 46, and the design 8 on the transfer film 58 is simultaneously injection molded.
The transfer film 58 has a longitudinal direction mark 82 and a width direction mark 84, and the transfer film 58 has a longitudinal direction mark 82 and a width direction mark 84 in the mold on the side where the film positioning device 52 is installed. Either or both of a longitudinal direction sensor 66 that detects the mark 82 and a width direction sensor 68 that detects the width direction mark 84 are provided, and both sensors 66 or 68 detect the mark 82 or 84.

The longitudinal direction mark is placed on a line in the longitudinal direction of the film passing through the center of the pattern, the longitudinal direction sensor is placed on a line in the longitudinal direction of the film passing through the center of the mold, and the width direction sensor is placed on a line in the longitudinal direction of the film passing through the center of the mold. It is preferable that they be arranged on a line passing through the center in the width direction of the film.

(e) Operation The longitudinal direction sensor detects the longitudinal direction mark of the transfer film and outputs a signal, and the film positioning device thereby positions the transfer film in the longitudinal direction. Similarly, the width direction mark is detected by the width direction sensor, and positioning in the width direction is performed. Detection of the longitudinal direction mark and the width direction mark is performed by a longitudinal direction sensor and a width direction sensor provided in the mold, so the plane on which light is projected and reflected is perpendicular to the surface of each mark. This makes it possible to detect the position of each mark with high positional accuracy.

(f) Examples Examples of the present invention will be described below with reference to FIGS. 3 to 6.

A fixed mold 44 and a movable mold 46 are attached to the fixed platen 40 and the movable platen 42, respectively. When the fixed mold 44 and the movable mold 46 are closed, they are guided by the guide pin 48 and the bush 50 and come into close contact with each other. This mold is a convex portion 44a of a fixed mold 44.
and two molding parts (transfer positions) formed by the recessed part 46a of the movable mold 46. A film positioning device 52 is provided on the movable platen 42. The film positioning device 52 can feed and stop the transfer film 58 guided by the guide rolls 54 and 56 to a predetermined position by means of a longitudinal drive device (not shown). Further, the film positioning device 52 can be moved in the horizontal direction by a widthwise driving device (not shown). The transfer film 58 includes guides 60a, 60b and guides 62a, 62b for preventing flapping.
are guided at the upper and lower parts of the movable mold 46. Further, the transfer film 58 is also guided by a guide 63 provided at the center of the movable mold 46. A speed switching longitudinal direction sensor 64 is provided in the stationary part above the mold. A longitudinal sensor 66 is provided in a recess 46b in the center of the movable mold 46. Further, a width direction sensor 68 is provided at a position on a horizontal line passing through the center position of the movable die 46. FIG. 5 shows an enlarged view of the state in which the longitudinal direction sensor 66 and the width direction sensor 68 are provided within the movable mold 46. The longitudinal sensor 66 is fixed within the recess 46b of the movable mold 46 by a support 70. The longitudinal direction sensor 66 is an optical switch and has a light emitting section 66a and a light receiving section 66b arranged parallel to the film width direction. The light emitting section 66a and the light receiving section 66b are connected to an amplifier (not shown) outside the movable mold 46 by glass fiber wires 72a and 72b, respectively. The width direction sensor 68 is attached within the recess 46c of the movable mold 46 by a support 74. The width direction sensor 68 is an optical switch similar to the longitudinal direction sensor 66, and has a light emitting part 68a and a light receiving part 68b, but the light emitting part 68a and the light receiving part 68b are arranged parallel to the longitudinal direction of the film. . The light emitting section 68a and the light receiving section 68b are connected to an amplifier by glass fiber wires 76a and 76b, respectively. Note that the guide 63 described above is of the movable type 4.
It is supported by a support 78 fixed to 6. Note that, as shown in FIG. 3, the fixed mold 44 is provided with a recess 44b for receiving the guide 63 when the movable mold 46 is in close contact with the mold 44.

On the left side of the transfer film 58 as seen in FIG. 4, longitudinal marks 80 for speed switching are provided at predetermined intervals.
is printed. Similarly, longitudinal marks 8 are placed at predetermined intervals in the center of the transfer film 58.
2 is printed. In addition, a transfer film 58
A width direction mark 84 is printed on the right side when viewed in FIG. The width direction mark 84 has a predetermined length in the longitudinal direction of the film. A pair of patterns 86 are printed on the transfer film 58 so as to correspond to the two concave portions 46 a and the convex portions 44 a of the movable mold 46 and the fixed mold 44 .

Next, the effect will be explained. First, the transfer film 58 is sent at high speed in the longitudinal direction (Y direction shown in FIG. 4) by a longitudinal direction driving device (not shown). When the speed switching longitudinal direction sensor 64 detects the speed switching longitudinal direction mark 80 on the left side of the transfer film 58, the feeding speed of the transfer film 58 is switched from high speed to low speed. At this time, the lower pattern 86 has passed the longitudinal direction sensor 66. Since the longitudinal direction sensor 66 is configured to be able to detect the mark at the same time as the speed is switched to low speed, the longitudinal direction sensor 66 will not mistakenly recognize the pattern 86 as the longitudinal direction mark 82. When the transfer film 58 is fed by a predetermined amount after being switched to a low speed, the longitudinal direction mark 82 at the center of the transfer film 58 reaches the position of the longitudinal direction sensor 66. When the longitudinal mark 82 is detected by the longitudinal sensor 66, the longitudinal drive is stopped and the longitudinal positioning of the film is completed. Next, positioning in the film width direction is performed. That is, the transfer film 58 is moved in the film width direction (X direction shown in FIG. 4) while being supported by the guide rolls 54 and 56 by a width direction drive device (not shown). The width direction mark 84 provided on the right side of the transfer film 58 in FIG. 4 is the width direction sensor 6.
When detected by 8, the widthwise driving device stops and positioning of the film in the widthwise direction is completed.

Next, the improved positioning accuracy of the transfer film 58 according to the present invention will be explained based on FIG. 6 in comparison with the conventional example shown in FIGS. 1 and 2. Assuming that point G is the transfer center position, conventionally a mark has been detected at a point a that is separated from point G by Y' in the longitudinal direction of the film and by _X1 in the width direction of the film. In this case, if the transfer film 58 is tilted by an angle α, an error ΔY corresponding to the distance between point b and point C will occur on the longitudinal center line of the film. That is, △Y=X ₁ ×
It becomes tanα. Further, an error ΔX corresponding to the distance between the h point and the i point is generated in the film width direction. That is, ΔX=Y ₁ ×tanα. However, according to the present invention, the longitudinal direction sensor 66 is located on the center line of the transfer film 58, and the longitudinal direction sensor 66 is located on the center line of the transfer film 58.
The value of X ₁ is 0. Therefore, the transfer film 5
Even if there is an inclination in the film 8, the error in the longitudinal direction of the film can be made almost zero. Further, the width direction sensor 68 is arranged on a line parallel to the film width direction passing through the transfer center position G (for example, point e), and the dimension corresponding to _Y1 is zero. Therefore, even if the transfer film 58 is tilted, the width direction error ΔX can be made almost zero. As a result, the device according to the invention allows extremely accurate positioning of the film in both the longitudinal and width directions. In addition, on the position where the longitudinal direction sensor 66 and the width direction sensor 68 are provided,
A guide 63 is provided to guide the transfer film 5.
8 is prevented from flapping, and the sensor 66 and
68 and marks 82 and 84 on the transfer film 58
Since the distance between
The film can be positioned more accurately. Further, the light emitting part 66a of the longitudinal direction sensor 66
and the light receiving section 66b, and the light emitting section 68a and the light receiving section 68b of the width direction sensor 68 are aligned with the marks 82 and 8.
Since the plane on which the light is projected and reflected is arranged perpendicular to the moving direction of the marks 82 and 84, the positions of the marks 82 and 84 can be detected with high accuracy. Furthermore, even if there is a printing error in the position of the pattern 86 printed on the transfer film 58, since the positions of the marks 82 and 84 are close to the pattern 86, the error during transfer can be avoided using conventional methods. It can be made smaller than the case.

Although one embodiment of the present invention has been described above, the present invention can also be implemented by adding the following changes to this embodiment.

In the above embodiment, two sensors, the longitudinal direction sensor 66 and the width direction sensor 68, are arranged in the mold, but only one of the sensors may be arranged in the mold.

The longitudinal direction sensor 66 or the width direction sensor 68 is
Even if the position is other than that of the above embodiment, if the longitudinal direction sensor 66 or the width direction sensor 68 is placed in the mold, the position of the longitudinal direction sensor 66 or the width direction sensor 68 will approach the center of the transfer position, so there will be an error when the transfer film 58 is tilted. can be made smaller, and the effect of improving positioning accuracy can be obtained.

In the described embodiment, the longitudinal direction sensor 66 is provided at the center of the mold, but even if it is not located at the center, it is possible to obtain similarly high positional accuracy as long as it is on a vertical line passing through the center of the mold. Therefore, the present invention can be applied even when the molded product is located at the center of the mold. In this case, as the position of the longitudinal direction sensor 66 is changed, the shape of the guide may be changed or a new guide may be provided.

In the above embodiment, the speed switching longitudinal direction sensor 64 for switching the feeding speed of the transfer film 58 from high to low speed was placed outside the mold, but this speed switching longitudinal direction sensor 64 was also placed inside the mold. There is no problem in placing it.

In the above embodiment, the film positioning device 52 is attached to the movable platen 42 side, but it may be attached to the fixed platen 40 side. In this case, the longitudinal direction sensor 66
A width direction sensor 68 is also attached to the fixed mold 44 .

(G) Effects of the Invention As explained above, according to the present invention, the transfer film can be accurately positioned at the transfer position even when the distance between the transfer film and the molding die changes slightly. be able to. Further, even if the distance between the transfer film and the molding die is very small, there is no problem in reading the marks, and the positioning accuracy can be improved. The present invention can be applied to cases where the molding section is located at the center of the mold, and also to cases where a large number of molding sections are transfer-molded at the same time.

[Brief explanation of the drawing]

1 is a diagram showing a conventional transfer molding device, FIG. 2 is a diagram showing the transfer molding device shown in FIG. 1 taken along the - line, FIG. 3 is a diagram showing a transfer molding device according to the present invention, Figure 4 shows the transfer molding apparatus shown in Figure 3.
FIG. 5 is a sectional view taken along the - line of FIG. 4, and FIG. 6 is a diagram showing the principle of the positioning error invention. 40... fixed plate, 42... movable plate, 44... fixed mold (mold), 44a... convex part, 46... movable mold (mold), 46a... recessed part, 48... guide pin,
50... Bush, 52... Film positioning device, 54, 56... Guide roll, 58... Transfer film, 60a, 60b, 62a, 62b...
... Guide, 63 ... Guide, 64 ... Longitudinal direction sensor for speed switching, 66 ... Longitudinal direction sensor, 68
... Width direction sensor, 82 ... Longitudinal direction mark, 8
4...width direction mark, 86...design.

Claims (1)

[Claims] 1. Positioning the transfer film in the longitudinal direction and the width direction by a film positioning device provided on the mold side of either the fixed mold or the movable mold,
In 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 transfer film has a longitudinal mark and a width direction mark. One or both of a longitudinal direction sensor for detecting the longitudinal direction mark and a width direction sensor for detecting the width direction mark are provided in the mold on the side where the film positioning device is installed. A transfer molding device characterized in that it is arranged to detect marks from a direction perpendicular to a film surface. 2 The longitudinal direction mark is placed on a line in the longitudinal direction of the film passing through the center of the pattern, the longitudinal direction sensor is placed on a line in the longitudinal direction of the film passing through the center of the mold, and the width direction sensor is placed on a line in the longitudinal direction of the film passing through the center of the mold. 2. The transfer molding device according to claim 1, wherein the transfer molding device is disposed on a line passing through the film in the width direction of the film. 3. The transfer molding apparatus according to claim 1 or 2, wherein a guide for guiding the transfer film is provided adjacent to the longitudinal direction sensor and the width direction sensor.