JP2770871B2 - Injection molding method and apparatus for painting - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a painting injection molding method and apparatus for bonding a painting sheet simultaneously with injection molding. 2. Description of the Related Art In order to perform painting simultaneously with injection molding, generally, a painting sheet is preformed by vacuum molding in a female mold before injection molding, and then the molten resin is combined with the female mold and the male mold. Is injected from the male mold side, and a painted sheet is adhered to the surface. Conventionally, this type of molding has been carried out without trimming by interposing a leaf-shaped vacuum-formed sheet in advance, or by feeding a transfer film to carry out molding. [0004] However, the foliate shape is inefficient, the productivity is poor, and the transfer film cannot be deeply squeezed, and it is inferior in design and heavy feeling. Was rare. There is also a method of trimming the painted sheet around the mold and taking out the molded product. However, in this method, the parting portion and the window portion must be trimmed every time in a later process, which is inefficient. SUMMARY OF THE INVENTION In view of the foregoing, it is an object of the present invention to provide a painting injection molding method and apparatus capable of continuously feeding a rolled continuous sheet into a mold and performing painting simultaneously with injection molding. And Means for Solving the Problems The invention according to claim 1 is:
The painted sheet unwound from the unwinding roll is run while covering the opening of the female mold and wound up by a take-up roll, and the heating plate and the frame member holding the painting sheet together with the heating plate are integrally formed with the painting sheet. Move the painted sheet and the heating plate in the traveling direction and the direction perpendicular to the traveling direction and perform the positioning of the painted sheet and the heating plate in both the traveling direction of the painted sheet and the direction perpendicular thereto, and place the painted sheet between the heating plate and the frame member. Hold the heating plate and the frame member together by one pitch of the picture and bring the picture to the predetermined position with respect to the female mold.
After applying a painted sheet on the molding surface of the female mold in vacuum, combining the female mold and the male mold and injecting the molten resin from the male mold side to integrate the painted sheet with the injection resin for painting. An injection molding method, wherein a plurality of positioning marks are provided at a constant pitch along the traveling direction and a direction perpendicular to the traveling direction of the painted sheet on the painted sheet, and the positioning marks are provided at the constant pitch. The mark is detected by at least one pair of detectors provided on the upstream side and the downstream side along the running direction of the painted sheet on one of the heating plate and the frame member, thereby positioning the painted sheet and the heating plate. Is performed. According to a second aspect of the present invention, there is provided an unwinding and take-up roll for a painted sheet, which is installed so that the painted sheet runs while covering the opening of the female die, and a sheet for one pitch of the pattern of the painted sheet. A heating plate that can move from the upstream side to the upper side of the female die, a frame member that sandwiches the painting sheet together with the heating plate and moves with the heating plate, and that the heating plate and the frame member are integrated with the traveling direction of the painting sheet and It has a moving device for moving in a direction perpendicular to this, and a conveying device for reciprocating the heating plate and the frame member integrally by one pitch of the pattern, and having a female mold surface before injection molding. After the picture sheet is vacuum-adhered, the picture-forming injection-molding mold apparatus is used to combine the picture sheet and the injection resin by injecting the molten resin from the male side by combining the female mold and the male mold. So,
In the painted sheet, a plurality of positioning marks for the traveling direction of the painted sheet and a direction perpendicular to the traveling direction are provided at a constant pitch along the traveling direction, and one of the heating plate and the frame member is provided in the traveling direction of the painted sheet. An injection-molding apparatus for painting, characterized in that at least a pair of detectors for detecting positioning marks provided at a constant pitch are provided on the upstream side and the downstream side. According to the first and second aspects of the present invention, the heating plate and the frame member move integrally in the traveling direction of the painted sheet and in a direction perpendicular thereto, so that the painted sheet is traveling, for example. The heating plate and the frame member can be moved to a regular position with respect to the design of the painting sheet, even if the heating plate and the unwinding roll are shifted from side to side. In addition, positioning marks for the running direction of the painted sheet and a direction perpendicular to the running direction are provided at a constant pitch along the running direction on the painted sheet, and the positioning marks are attached to either the heating plate or the frame member. Since detection is performed by a pair of detectors provided on the upstream and downstream sides in the direction, the painted sheet can be positioned with higher precision than when detection is performed by a single detector. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a finished product formed according to the present invention. A painted sheet 2 is adhered to a surface of a main body 1 in which a molten resin is solidified. The letter 12 is drawn on the lower part of the painting sheet 2. FIG. 2 is a longitudinal sectional view of the injection molding apparatus M of the present invention. In the lower part, a male die 16 fixed to a fixed plate 20 and a male die 16 fixed to a moving plate 24 are formed. A female die 18 which is horizontally separated from and connected to the
Is movable by a pressure ram 22, and an ejector 26 is provided adjacent to the moving plate 24. The ejector 26 has a protruding pin (not shown) for discharging a molded product out of a mold after injection molding. I have. An injection device 28 is inserted into the center of the fixed platen 20 and the male die 16, and the molten resin 60 injected from the injection device 28 is injected into the injection hole 3 formed in the male die 16.
0 and is pressed into the cavity of the female mold 18. The painted sheet 32 travels vertically downward between the two dies, and the painted sheet 32 is held by an unwinding roll 34 located above and a take-up roll 36 located below, and includes upper and lower guide rolls. The running position is regulated by 38,38. A predetermined pattern is printed on the painting sheet 32 at a constant pitch, and if it is for back printing or transfer, it is set so that the printing surface is opposite to the female die 18. A positioning mark T (register mark) as shown in FIG. 3 is printed on the sheet at a constant pitch together with a symbol formed by printing, vapor deposition, coating or the like. The mark T includes a horizontal line a for determining the position in the vertical direction (X direction) and a vertical line b for determining the position in the left and right direction (Y direction), and these two lines a and b may be formed separately. A frame member 46 and a heating plate 44 disposed integrally opposite to the frame member 46 are disposed above the two molds. These two members 44 and 46 cooperate with each other to clamp the painted sheet 32. The painting sheet 32 is moved between the two dies. The frame member 46 is formed in a U-shape, and the rail 42
And two rails 42 are provided on both sides of the female die 18 in the vertical direction. The heating plate 44 has a heating section 44 inside.
The heating section 44a has a ventilation hole 50, and the ventilation hole 50 is connected to a not-shown compressed air pump via a common conducting hole 51. The heating plate 44 is vertically moved by an air cylinder 52, the cylinder 52 is rotatably held by a frame (not shown), and the heating plate 44 is separated from the frame member 46 by an air cylinder, oil cylinder, motor, or the like (not shown). It is moved in the direction of contact. Detectors 54 such as photoelectric tubes are provided above and below the heating plate 44 or the frame member 46 for detecting the mark T on the picture sheet 32, two detectors for detecting the X direction, and two detectors for detecting the Y direction. Preferably, two detectors 54 are provided. A bar member 56 for supporting the painted sheet 32 is provided below the female die 18 so as to be opposed to each other by an air cylinder (not shown) supported by the movable platen 24. Further, a vent hole 58 for evacuating is formed in the female die 18. As shown in FIG. 2 and FIG.
A trimming blade portion 61 is provided on the periphery of the opening portion, and a trimming blade portion 62 is provided also on a portion of the mold surface of the male die 16 which faces the blade portion 61. These blades 6
1 and 62 may be formed by quenching the edge of a normal mold to increase the hardness. The blade 61 preferably has a Y hardness of 53 to 56 ° (Rockwell hardness), and the blade 62 preferably has a hardness of 50 to 53 °. This is because the shearing portion usually has a thickness of about 1 mm to 2 mm depending on the thickness of the sheet. If the number of shots is large, the trimming accuracy of the worn portion decreases, but as described above, the hardness of the blade portions 61 and 62 differs. This can be prevented if you do. The blades 61 and 62 are set so that they can be replaced with one touch. Next, the operation of the present apparatus will be described. First, when the detector 54 detects the horizontal line a of the mark T on the sheet, the operation of a servo motor (not shown) for integrally moving the heating plate 44 and the frame member 46 is stopped, and then both the motors are moved in the Y direction. When the members 44 and 46 are moved by a servo motor (not shown) and the detector 54 detects the vertical line b, the servo motor stops and the heating plate 44 moves to a proper position with respect to the picture. Next, a sheet is adhered onto the heating section through the ventilation hole 50 of the heating section 44a. Further, the heating plate 44 is moved toward the frame member 46 by the operation of an air cylinder (not shown) to clamp the sheet 32 between the two members 44, 46. Thereafter, the two members 44 and 46 return to the reference position by the action of the servomotor, and as shown in FIG.
The air cylinder 52 supporting the heating plate 44 extends,
The frame member 46 and the heating plate 44 are integrally lowered from the reference position along the rail 42 and stop at a predetermined position on the female die 18.
Accordingly, the sheet is unwound by one pitch. Frame member 4
Since the lower part of 6 is open, the frame member 46 can surround the female mold 18, and the heating plate 44 holds the sheet and closes the cavity of the female mold 18. At this time, the pattern on the sheet is in the correct position (tuned position) with respect to the molding surface of the female mold.
It is installed in. In such a state, the female cavity is first evacuated through the air holes 58 of the female die 18. Thereafter, compressed air is sent from the ventilation holes 50 of the heating plate 44 to cause the sheet 32 to be peeled off from the surface of the heating section 44a.
Is adhered to the molding surface of the female mold 18 as shown in FIG.
In the case of deep tightening, that is, when the molding surface of the female mold is deep, a part of the heating plate 44 is moved to the molding surface side of the female mold while holding the sheet by a cylinder (not shown) or the like, and the sheet is vacuumed. Can be preformed without excessive stretching. In the above process, the cavity of the female mold 18 is evacuated and then the compressed air is sent from the heating plate side to attach the sheet to the molding surface of the female mold. It is also possible to exhaust air from the vent hole 58 while sending air. In this case, however, the air holes 58
It is necessary to provide many in the female mold. This is because air remains in the cavity. On the other hand, according to the former method, there is no need to provide a large number of air holes because no air remains in the female mold at the time of sheet molding. Therefore, traces of air holes generated on the surface of the molded product can be reduced. Thereafter, the heating plate 44 is lifted from the frame member 46 by the operation of an air cylinder (not shown), and the members 44 and 46 are returned to the reference positions shown in FIG. At this time, the stick member 56 clamps the painted sheet 32 so that the painted sheet 32 does not move. Next, as shown in FIG.
And merged with the male mold 16. Then, the blade 6
The painting sheet 32 is cut into parts corresponding to the finished product by the components 1 and 62. FIG. 7 is a cross-sectional view of a mold showing another embodiment having a core portion. Concave portions 63 and 64 are formed at opposing positions of the male mold 16 and the female mold 18, respectively. The core portion 65 is slidably fitted into the core portion 65, and the core portion 65 is configured so as to be freely protruded and retracted from the molding surface of the male mold 16 by a cylinder 70 housed in the male mold 16. A spring 66 is provided in the recess 64, and the spring 66 slidably holds a receiving member 67 that is urged outward. A blade 68 is formed around the tip of the core 65, and a blade 69 is formed around the recess 64. In addition, the recess 6
The position where 3 is provided does not interfere with the injection hole 30.
Thus, when the mold 70 is closed, the operation of the cylinder 70 causes the core 65
Into the recess 64. Then, as shown in FIG.
A punching hole 71 is formed in a part of the picture sheet 32 attached to the molding surface of the female die 18 in accordance with the shape of the opening of the recesses 63 and 64, and a punching hole (window) of a desired complicated shape is formed in one of the patterns. A finished product having a part can be obtained. Here, the size of the cylinder is preferably as small as possible and a hydraulic cylinder with high power is preferable. There is also a method of injecting resin after injecting the resin by a gate cut method (cutting of a resin injection port). However, trimming only the sheet reduces the cylinder pressure, so that a small cylinder can be used. According to the first and second aspects of the present invention,
By moving the heating plate and the frame member integrally in the traveling direction of the painted sheet and in a direction perpendicular thereto, for example, the painted sheet meanders while traveling, or even if the mounting position of the unwinding roll is shifted left and right, The heating plate and the frame member can be moved to a regular position with respect to the picture on the picture sheet. Further, on the painted sheet, positioning marks for the traveling direction of the painted sheet and a direction perpendicular to the traveling direction are provided at a constant pitch along the traveling direction, and this positioning mark is located upstream of the heating plate or the frame member in the traveling direction of the painted sheet. Since the detection is performed by a pair of detectors provided on the downstream side and the detection side, the positioning of the painting sheet can be performed with higher accuracy than when the detection is performed by a single detector. Thereafter, the painted sheet is sandwiched between the heating plate and the frame member, so that the shape of the finished product and the pattern can be positioned with high accuracy in both the sheet running direction and the direction perpendicular thereto.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a molded article with pictures. FIG. 2 is a longitudinal sectional view of the apparatus. FIG. 3 is a plan view of a painting sheet. FIG. 4 is a diagram illustrating a state in which preparation for preforming of a sheet is completed. FIG. 5 is a state diagram in a female mold after completion of preforming. FIG. 6 is a longitudinal sectional view of a male and female mold part during injection molding. FIG. 7 is a cross-sectional view of a mold showing another embodiment having a core portion. FIG. 8 is a perspective view of a completed product obtained by using the mold shown in FIG. 7; [Description of Signs] 16 Male type 18 Female type 32 Painting sheet 42 Rail 44 Heating member 46 Frame member 52 Cylinder 54 Detector 61, 62, 68, 69 Blade unit 63, 64 Recess 65 Core unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI // B29L 9:00

Claims (1)

(57) [Claims] The painted sheet unwound from the unwind roll is run while covering the female mold opening, and is wound up by the wind-up roll,
The heating plate and the frame member holding the painting sheet together with the heating plate are integrally moved in the traveling direction of the painting sheet and in a direction perpendicular to the traveling direction of the painting sheet so that the positioning of the painting sheet and the heating plate can be performed in the traveling direction of the painting sheet. Performed in both directions at right angles, sandwich the picture sheet between the heating plate and the frame member, and convey the heating plate and the frame member integrally by one pitch of the pattern to move the pattern to a predetermined position with respect to the female mold. Bring the pictured sheet to the molding surface of the female mold and attach the pictured sheet under vacuum, then combine the female and male molds and inject the molten resin from the male mold side to integrate the painted sheet and the injection resin. A painting injection molding method, wherein a plurality of positioning marks are provided on the painting sheet at a constant pitch along a traveling direction of the painting sheet and a direction perpendicular to the traveling direction. The positioning mark provided by the switch is detected by at least one pair of detectors provided on the upstream side and the downstream side along the running direction of the painting sheet on either the heating plate or the frame member. An injection molding method for painting, comprising positioning a sheet and a heating plate. 2. The unrolling and winding rolls of the painted sheet installed so that the painted sheet runs while covering the opening of the female mold, and can be moved from the upstream side of the sheet by one pitch of the pattern of the painted sheet to the upper side of the female mold. A heating plate, a frame member for holding the painting sheet together with the heating plate and moving together with the heating plate, and a movement for moving the heating plate and the frame member integrally in the running direction of the painting sheet and in a direction perpendicular thereto. Device, and a transfer device for reciprocating the heating plate and the frame member integrally by one pitch of the pattern, and after vacuum-adhering the pattern sheet to the molding surface of the female mold before injection molding, the female An injection molding mold apparatus for painting, in which the painted sheet and the injection resin are integrated by injecting a molten resin from the male mold side by combining a mold and a male mold, wherein the painted sheet has a Direction of travel and direct A plurality of positioning marks in the angular direction are provided at a constant pitch along the running direction, and are provided at a constant pitch on either the heating plate or the frame member on the upstream side and the downstream side along the running direction of the painted sheet. An injection-molding mold apparatus for painting, comprising at least a pair of detectors for detecting the positioning mark.