JPH04138230A - Manufacture of reflecting plate for antenna - Google Patents

Abstract

PURPOSE:To eliminate the possibility of occurrence of peeling of a resin film off an overlapping line of the film and an antenna main body (resin molded product) by pushing a peripheral section of the film clamped between a fixed mold and a movable mold into a cavity following the resin injection into the cavity. CONSTITUTION:A peripheral edge of a resin film X clamped by a fixed mold 1 and a movable mold 2 is peeled off by the pressure of molten resin Y following the resin injection and pushed into a cavity, and the ends of said film peripheral edges Xa and Xb are coated with the resin Y to form a web section Ya. The resin film X is embedded into the surface of the web section Ya by the above-mentioned process, and an overlapping line of the film X and an antenna main body is not exposed on a molded reflecting plate.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing a reflector for an antenna used for satellite broadcast reception and the like.

(Prior Art) In the above-mentioned parabolic antenna used for receiving satellite broadcasting, etc., the reflector must have a predetermined strength and radio wave reflecting function, and must also have good weather resistance for outdoor installation. sexuality is required.

Therefore, for example, in Japanese Patent Application Laid-open No. 1-144704, the antenna body is installed in a mold, and a thin body made of a conductive metal sheet with a weather-resistant film is placed on the conductive sheet to reflect radio waves. A technique has been disclosed for manufacturing a parabolic antenna by placing the layer so as to fit on the reflective surface of the antenna body and integrating the antenna body and the thin film body by vacuum-pressure forming.

According to this, an antenna reflector including a radio wave reflective layer and a weather-resistant layer covering the same can be manufactured in one step by the vacuum-pressure forming process.

However, in the above method for producing a reflector plate, the antenna body and the thin film body are first manufactured in separate processes, and then the two are integrated by vacuum-pressure forming as described above, which increases the number of processes and reduces costs. As the cost increases, manufacturing becomes complicated and inefficient.

To deal with this, a fixed mold is clamped to the movable mold while a thermoplastic resin film having a radio wave reflective layer and a weatherproof layer is adsorbed to the cavity forming surface of the movable mold. It is conceivable that by injecting molten resin into the cavity from the side, the antenna body is molded with the molten resin and at the same time the above resin film is applied to the surface of the antenna body. According to this method, there is no need to separately manufacture the antenna body, the manufacturing process of the reflector plate is simplified, and the cost is also reduced.

(Problems to be Solved by the Invention) By the way, in manufacturing the reflector by injection molding as described above, the cavity constituting surface of the movable mold is made into a convex parabolic curved surface that imitates the radio wave reflecting surface of the reflector, and the movable mold The air between the resin film sent into the cavity and the cavity forming surface is evacuated and the resin is injected with the resin film adsorbed to the cavity forming surface, and the heat and pressure of the injected resin at that time causes the resin to The film is stretched and deformed so as to be in complete contact with the cavity forming surface, and in this state, the resin film A is covered with the surface of the resin molded product B, which is the antenna body, as shown in FIGS. 11 and 12. I will have to wear it.

However, in the above-mentioned reflector C, a sea urchin/tube E and a flange F (some without flanges are also available) are usually provided around the radio wave reflecting surface from the viewpoint of main body strength, so according to the above injection molding. Resin film A will be applied to these web E and flange F, but in that case, in the product, resin film A will be applied to the end face of flange F.
The seam G between the molded product B and the resin molded product B will be exposed,
There is a risk that the resin film X will peel off from this seam G.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a reflector for an antenna in which the seam between the antenna body and the resin film attached to the antenna body is not exposed at the end face of the reflector.

(Means for Solving the Problems) That is, the present invention provides a thermoplastic resin film in which a radio wave reflective layer and a weather-resistant layer are laminated on one side of a film base.
In a method for manufacturing an antenna reflector that is attached to the surface of an antenna main body in which a sea urchin/tube portion is provided around a radio wave reflecting surface, the film base side of the resin film is adsorbed to the suction head, and the suction head is a film molding step of cutting out the resin film into a circle that is one size larger than the radio wave reflecting surface by joining a film mold to the mold, and carrying the cut out resin film to the front of the cavity forming surface of the movable mold; a film setting step of bringing the suction head into pressure contact with a movable mold, sandwiching the peripheral edge of the resin film between the two, and separating the resin film from the suction head by sucking air between the cavity forming surface and the resin film; , a mold clamping step of moving the suction head out of the front position of the movable mold, clamping the fixed mold and the movable mold together, and clamping the peripheral edge of the resin film; Molten resin is injected into the cavity from a fixed mold, and the clamped peripheral edge of the film is pushed into the cavity by the pressure of the molten resin, thereby embedding the peripheral edge of the film into the surface of the web portion of the antenna body. It is characterized by consisting of a resin molding process.

(Function) According to the above method, 1. The peripheral edge of the resin film, which was clamped by the fixed mold and the movable mold, is peeled off from the clamped state by the pressure of the molten resin as the resin is injected, and falls into the cavity. The resin covers the tip of the peripheral edge of the film to form a web portion. Therefore, the resin film is embedded in the surface of the web portion, and in the molded reflector, the seam between the film and the antenna body (resin molded product) is not exposed to the outside.

(Example) Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 shows an injection molding device embodying the method of the present invention, in which a movable mold 2 is arranged facing a fixed mold 1 so as to be separable from it, and is positioned directly above both molds 1.2. Suction head 3
and a film preforming mold 4 are arranged, and in a state where the movable mold 2 is separated from the fixed mold 1, the suction head 3 can be raised and lowered between a rising value 1 shown by a solid line and a lowering position shown by a chain line. .

The suction head 3 adsorbs a thermoplastic resin film X, which will be described next, in the raised state, cuts out the film X into a predetermined shape in cooperation with the film preforming mold 4, performs preforming, and after this preforming, a movable mold 2 and carry in the resin film X.

Here, to give an example of the resin film X, as shown in FIG. The radio wave reflecting layer X2 made of the aluminum sheet is used as an intermediate layer, and the weather-resistant layer X made of an acrylic resin sheet is formed thereon. Further, depending on the thickness of the aluminum sheet, an aluminum sheet reinforcing layer such as a polyester sheet may be provided between the reflective layer X2 and the weather-resistant layer X. However, the resin film X is not limited to the above, as long as the method of the present invention described later can be applied. For example, the weather-resistant layer X made of the above acrylic resin sheet
3 and the reflective layer X2 may be provided with an adhesive layer in place of the material sheet X1, which may also be used as a resin film.

The suction head 3 is supported by a lifting table 5, and a piston rod 7 of a fluid pressure cylinder 6 whose upper end is connected to a fixed part (not shown) is connected to the lifting table 5. The lifting platform 5 is raised and lowered by the telescopic operation.

In addition, the suction head 3 is configured to move toward and away from the movable mold 2 in the lowered state, so that the rods 8, 8 connected to the back surface of the suction head 3 are moved laterally to the lifting platform 5 as shown in FIG. In addition to being freely slidably supported, the lifting platform 5 is equipped with a solenoid 9.9 that pushes and pulls these rods 8, 8, and the suction head 3 comes into contact with the movable mold 2 when the solenoid 9.9 is energized. When the excitation is removed, the force of the spring member 10.10 causes the movable mold 2 to move away from the movable mold 2.

The suction head 3 also includes the film preforming mold 4 described above.
A large number of small-diameter ventilation holes 1 are provided on the film suction surface 3a facing the
1 . It is connected. And air hose 1
3 is switched and connected to a vacuum pump 15 and a compressor 16 by a three-way switching valve 14. The vacuum pump 15 applies an air suction force to the suction head 3 through the air hose 13 to adsorb the resin film X to the suction head, and the compressor 16 sends compressed air to the suction head 3 to create a film vacuum as described later. It functions to release the adsorbed resin film X from the suction head 3 under pressure during air pressure molding. The film adsorption surface 3a is coated with Teflon in order to ensure good film releasability during vacuum-pressure forming of the film.

Furthermore, the film suction surface 3a of the suction head 3 is
7 and a flat part 18 surrounding the convex part 17,
A curved portion 1 in which the peripheral edge of this convex pedestal portion 17 is connected to the flat portion 18
7a, and the outer corner of the flat portion 18 is an etched portion 19 for cutting the film.

In addition, in the suction rod 3, a clamp plate 20 is attached surrounding the film suction surface 3a consisting of the above-mentioned convex part 17 and flat part 18, and this clamp plate 20 is held by the force of the spring member 21.21. It is urged so as to always protrude toward the film preforming mold 4 side rather than the suction surface 3a.

On the other hand, the film preforming mold 4 described above is composed of a holder 22 and a mold body 23 built into the holder 22, and the holder 22 is attached to a support frame 24, and
5A, and a positioning pin 26 is provided protruding from the upper surface of the holder 22. Further, the mold body 23 is made capable of protruding and retracting from the holder 22 by a fluid pressure cylinder 25B, and is in contact with the film forming part 27 into which the convex part 17 of the suction head 3 fits, and the flat part 18. A film forming part 28 is recessed into the front surface of the mold body 23, and an inner corner of the holder 22 surrounding the mold body 23 is an etched part 29 for cutting the film.
It is said that

This film preforming mold 4 is brought into and out of contact with the suction head 3 by the operation of the fluid pressure cylinders 25A and 25B, and in preparation for this joining, the head 3 is raised on the side of the suction head 3. At this time, the arm 30 that engages with the support frame 24 and the pin hole 3 into which the positioning pin 26 enters.
1 is provided.

In the above-mentioned fixed type 1 and movable type 2, the fixed type 1 is attached to the fixed platen 32, the movable type 2 is attached to the movable platen 33, and the movable platen 33 is moved near and far from the fixed platen 32 by the hydraulic cylinders 34 and 34. By being moved, the movable type 2
and fixed mold 1 are opened and closed using tie bars (not shown) as guides. A parabolic antenna-shaped cavity is formed between the molds when the molds 1 and 2 are joined together.

In the fixed mold I described above, as shown in FIG. 4, the cavity plate 35 is held by the support block 36, and the cavity plate 35 has a concave curved cavity forming surface 38 surrounded by the mold matching surface 37 of the support block 36. is formed, and a gate for resin injection is opened in this cavity forming surface 38, while a sprue 40 of a spool bush 39 provided in the support block 36 is communicated with the gate.
As a result, the molten resin supplied from the injection nozzle 41 to the sprue 40 is injected into the above-mentioned cavity through the gate.

In addition, the cavity forming surface 38 has a flange portion Yb (
An annular recess 42 is formed for forming a portion (corresponding to the flange F in FIG. 11).

In the movable mold 2 , a cavity plate 43 is held by a support block 44 , and a convexly curved cavity forming surface 45 facing the cavity forming surface 38 of the fixed mold 1 is formed on the cavity plate 43 . Further, a ring block 46 is fitted onto the cavity plate 43. On the other hand, a plurality of recesses 47, 47 are formed in the back surface of the support block 44 at positions surrounding the cavity plate 43, and one end of a slide wood 48, 48 that penetrates the support block 44 in the front and back is engaged with these recesses 47. The slide rods 48 and 48 can be slid back and forth by a certain amount, and the other ends of the slide rods 48 and 48 are connected to the ring block 46. In that case, spring members 47, 47 are interposed between the support block 44 and the ring block 46, and the ring block 46 is biased so as to protrude from the cavity plate 43 toward the fixed mold l side.

Furthermore, the cavity plate 45 of the ring block 46
A film suction portion 49 (the illuminating surface is shown as a concave shape in FIGS. 7 and 8 in order to clarify the existence of this suction portion 49) is formed on the mold matching surface 48 surrounding the ring block. A concave portion 50 continuous to the film suction portion 49 is formed on the inner circumferential surface of the fixed mold 1 .
When the ring block 46 is retreated against the spring members 47 and 47 due to mold clamping between the movable mold 2 and the movable mold 2, the concave portion 50
are configured to extend continuously around the circumference of the cavity forming surface 45 (shape B in FIG. 8). Note that the recessed portion 50 is formed when the web Y of the antenna body shown in FIG. 9 is formed during resin molding.
a (a portion corresponding to web E in FIG. 12).

In the movable mold 2, the cavity forming surface 45 is inserted through the sliding contact area between the cavity plate 43 and the ring block 46.
Air suction passages 51 and 52, which are open at the film suction section 49 and at the film suction section 49, are provided at regular intervals in the circumferential direction.

These air suction passages 51 and 52 are led to the back of the cavity plate 43 and communicated with an air suction means (not shown) via an annular air passage 53 provided in the chain portion.

Next, the molding operation in the mold device having the above structure will be explained.

As shown in FIG. 1, a state in which the fixed mold 1 and the movable mold 2 are separated from each other at a certain interval and the suction head 3 is in the raised position is called a standby state. In this standby state, the support frame 2 is inserted into the engagement groove 30 of the suction head 3 as shown in FIG.
4 are engaged, and the suction head 3 is positioned with respect to the film preforming mold 4.

From this state, the front side of the suction head 3 and the preforming mold 4 are
A thermoplastic resin film X is supplied between the
is connected to the suction head 3 and an air suction force is applied to the head, air is suctioned through the ventilation holes 11...11 of the suction head 3, and the resin film X is adsorbed to the film suction surface 3a by the suction force. Note that this adsorption is caused by resin film
This is done by bringing the base sheet X into close contact with the suction surface 3a.

After the above-mentioned suction, the film preforming mold 4 is moved forward with respect to the suction head 3 by the operation of the fluid pressure cylinder 25A, the positioning bin 26 enters the pin hole 31, and the preforming mold 4
Both 3 and 4 are joined with the suction head 3 aligned.

In this joining, first, the peripheral part of the resin film As a result, the flat portion 18 and the etched portions 19, 29 of the holder 22 are engaged with each other, and the resin film X is cut around the film suction surface 3a. Then, the fluid pressure cylinder 25B is activated, the mold body 23 moves forward, and the film forming parts 27 and 28 are fitted into the convex part 17 and the flat part 18, as shown in FIG. The resin film X is molded.

In this molding process, as shown in FIG. 6, the resin film X is cut out into a circle that is one size larger than the radio wave reflecting surface of the antenna body, and a curved part Xa and a flat part xb are formed at the peripheral edge of the cut out resin film X. A typing consisting of is applied.

Next, as the film preforming mold 4 is moved forward and separated from the suction head 3, the suction head 3 descends to the position shown by the chain line in FIG. 1 while adsorbing the preformed resin film X. The resin film X is carried to the front of the movable mold 2.

Then, the solenoid 9.9 is energized, and the suction head 3 moves forward toward the movable mold 2 and comes into close contact with it.

Due to this close contact, the flat portion 18 and the clamp plate 20 come into contact with the ring block 46 as shown in FIG. 7, but the ring block 46 remains in the protruding state due to the force of the spring members 47, 47 and does not retreat. Further, the resin film X is fed into the front surface of the cavity forming surface 45 with its preformed curved portion Xa fitting into the concave portion 50 of the movable mold 2 and with its flat portion xb being in close contact with the film suction surface 149.

From this state, the resin film X is vacuum-pressure formed. That is, in the movable mold 2, the air suction means is activated, and the air between the resin film X and the cavity forming surface 45 is discharged to the outside from the air passage 53 via the air suction passages 51 and 52. After the space between the resin film Air is blown out from the vents 11...11. Therefore, the resin film X and the cavity forming surface 45
The resin film It is attracted in a state that almost follows the constituent surface 45. It should be noted that since the resin film X had its base sheet Xl side suctioned by the suction head 3, the weather-resistant layer X3 faced the cavity forming surface 45.

After the vacuum-pressure forming, the suction head 3 retreats and rises. However, in the movable mold 2, the air suction force by the air suction means continues to be applied between the resin film let

Therefore, of the preformed peripheral portion of the resin film X, the flat portion xb is attracted to the film attraction surface 49 of the movable mold 2, and the curved portion Xa continues to be attracted to the recessed portion 50.

After the suction head 3 is raised, the fixed mold 1 and the movable mold 2 are clamped. Due to this mold clamping, the ring block 46 retreats against the spring members 47, 47, and the concave portion 50 is continuously connected to the convex curved surface of the cavity forming surface 45, as shown in FIG. Further, in the mold clamping state, the flat portion Xb of the resin film X is clamped by the film suction surface 49 portion of the movable mold 2. However, it is assumed that the clamping force in this portion does not prevent the flat portion xb from being dragged into the cavity during resin injection, which will be described below. Then, the molten resin Y is injected into the cavity from the gate, and the resin film X exhibits appropriate elongation due to the heat and pressure at that time and completely adheres to the cavity forming surface 45, and in this state, the antenna body is resin-molded. In this molding, the base sheet x1 of the resin film X is melted and integrated with the injected resin, so that the resin film ).

By the way, during the resin injection described above, the preformed flat part xb of the resin film The flat portion xb is dragged into the recessed portion 50 by the pressure of the resin. Therefore, the resin Y is molded so as to cover the film tip Xc of the flat portion xb as shown in FIG. 9, and in the resulting product, the resin film The joint between the resin film X and the molded resin Y is not exposed to the outside.

As a result, in the manufactured antenna reflector, the resin film X will not peel off from the seam.

Although the web Ya and the flange Yb were provided on the antenna body in the resin molding in the above embodiment, it is also possible to provide only the web Ya, and in that case, the shape shown in FIG. 11 is an example. It can be considered as

(Effects of the Invention) As is clear from the above description, according to the present invention,
As the resin is injected into the cavity, the peripheral edge of the film that is clamped by the fixed and movable types is torn off the clamp and pushed into the cavity, and the leading edge of the film's peripheral edge is covered with resin. A web portion is formed over it. Therefore, the resin film is embedded in the surface of the web portion, and in the molded reflector, the seam between the film and the antenna body (resin molded product) is not exposed to the outside. Therefore, there is no possibility that the resin film will peel off from the seam, improving product quality.

[Brief explanation of the drawing]

The drawings show an embodiment of the method for manufacturing an antenna reflector according to the present invention, FIG. 1 is a schematic diagram of a mold apparatus for resin injection molding that embodies the method of the present invention, and FIG. A configuration diagram showing an example of a resin film, FIG. 3 is an enlarged view of the suction head portion in FIG. 1, FIG. 4 is an enlarged view of the mold in FIG. 1, and FIGS. 5 to 9 are explanatory views of molding operation. FIG. 5 is an explanatory diagram of film preforming operation, and FIG.
The figure is a cross-sectional view of a preformed resin film, Figure 7 is an explanatory diagram of the film adsorption operation to the movable mold, Figure 8 is an explanatory diagram of the mold clamping operation, Figure 9 is an explanatory diagram of the resin injection molding operation, and Figure 10 is FIG. 3 is a cross-sectional view showing a modification of the antenna reflector. FIG. 11 is a perspective view of a reflector for an antenna manufactured according to the prior art, and FIG. 12 is an enlarged cross-sectional view of a main part of the reflector. X...resin film, Xa, Xb...film peripheral part (Xa is curved part, xb is flat part), Y...molten resin, Ya...web, 1...fixed type, 2... ...Movable mold, 3...Suction head, 4...Film mold, 4
5... Cavity configuration surface. Zugen sokubuebuesen zuzu zu zu zu zu zu

Claims (1)

[Claims] (1) An antenna reflector in which a thermoplastic resin film, in which a radio wave reflective layer and a weather-resistant layer are laminated on one side of a film base material, is applied to the surface of the antenna body where a web portion is provided around the radio wave reflective surface. A method for manufacturing a plate, wherein the resin film is shaped into a circular shape one size larger than the radio wave reflecting surface by joining a film mold to the suction head with the film base side of the resin film adsorbed to the suction head. a film forming step of cutting out the resin film and transporting the cut out resin film to the front surface of the cavity forming surface of the movable mold, pressing the suction head against the movable mold and sandwiching the peripheral edge of the resin film between them; and a film setting step of separating the resin film from the suction head by sucking the air between the cavity forming surface and the resin film, and a step of separating the fixed mold and the movable mold after the suction head is moved out of the front position of the movable mold. and clamping the peripheral edge of the resin film, injecting molten resin from a fixed mold into the cavity formed between the two molds, and clamping the resin film by the pressure of the molten resin. A method for producing a reflector for an antenna, comprising a resin molding step of embedding the peripheral edge of the film into the surface of the web portion of the antenna main body by pushing the peripheral edge of the film into a cavity.