WO2023013375A1

WO2023013375A1 - Method of manufacturing transparent plastic cover for vehicle

Info

Publication number: WO2023013375A1
Application number: PCT/JP2022/027570
Authority: WO
Inventors: 正幸小林
Original assignee: 株式会社小糸製作所
Priority date: 2021-08-06
Filing date: 2022-07-13
Publication date: 2023-02-09
Also published as: JPWO2023013375A1

Abstract

The present invention provides a method in which a metal wire is secured to a first die while following a plurality of guide pins provided on the first die. A second mold and the first mold are brought into contact with each other to form a cavity. A molten, transparent resin is injected into the cavity and the transparent resin is cured inside the cavity to form a transparent plastic cover for a vehicle, the transparent plastic cover containing a metal wire for a heater.

Description

Manufacturing method of transparent resin cover for vehicle

The present disclosure relates to a method for manufacturing a transparent resin cover for vehicles.

Patent Document 1 discloses a vehicle lamp in which a metal wire for a heater is arranged on the lens in order to melt the snow adhering to the lens and eliminate fogging. In Patent Document 1, metal wires are laid on the surface of the lens after the lens is produced.

Japanese Patent Application Laid-Open No. 2006-79933

The inventor considered injection molding the lens with the metal wire laid thereon. However, in such a process, the metal wires are displaced during injection molding, making it difficult to produce a lens in which the metal wires are arranged in a desired shape.

An object of the present disclosure is to provide a method for manufacturing a transparent resin cover for a vehicle in which metal wires for heaters can be easily laid in a desired shape.

A method for manufacturing a transparent resin cover for a vehicle according to one aspect of the present disclosure includes:
A method for manufacturing a transparent resin cover for a vehicle having a metal wire for a heater, comprising:
a step of fixing the metal wire to the first mold along a plurality of guide pins provided on the first mold;
contacting the second mold and the first mold to form a cavity;
injecting a molten transparent resin into the cavity and curing the transparent resin within the cavity to form the transparent resin cover having the metal wires.

A method for manufacturing a transparent resin cover for a vehicle according to one aspect of the present disclosure includes:
A method for manufacturing a transparent resin cover for a vehicle having a metal wire for a heater, comprising:
a metal wire fixing step of fixing the metal wire to the first mold along a plurality of guide pins provided on the first mold;
a first cavity forming step of forming a first cavity by bringing the second mold and the first mold into contact with each other;
a resin body forming step of injecting a molten first transparent resin into the first cavity and curing the first transparent resin in the first cavity to form a resin body having the metal wire;
A second cavity forming step of separating the first mold from the second mold while holding the resin body, and bringing the second mold and the third mold into contact with each other to form a second cavity. and,
a transparent resin cover forming step of injecting a molten second transparent resin into the second cavity and curing the second transparent resin in the second cavity to form the transparent resin cover having the metal wire; , provided.

According to the present disclosure, it is possible to provide a method for manufacturing a transparent resin cover for a vehicle in which the metal wire for the heater can be easily laid in a desired shape.

The structure of the transparent resin cover for vehicles which concerns on this embodiment is illustrated. It illustrates a configuration of a cross section along line 2-2 in FIG. 1 viewed in the direction of the arrow. The vehicle lamp to which the transparent resin cover is attached is illustrated. The flow of the manufacturing method of a transparent resin cover is illustrated. 5 illustrates the metal wire fixing step of FIG. 4; It is the figure which looked at the structure except the 2nd metal mold|die of FIG. 5 from the direction of the arrow 6, and illustrates arrangement|positioning of the guide pin of a 1st metal mold|die. 5 illustrates the first cavity forming step of FIG. 4; The resin body formation process of FIG. 4 is illustrated. 5 illustrates the second cavity forming step of FIG. 4; The transparent resin cover formation process of FIG. 4 is illustrated. Another flow of the manufacturing method of a transparent resin cover is illustrated. 12 illustrates the metal wire fixing step of FIG. 11; 12 illustrates the cavity forming process of FIG. 11; The transparent resin cover formation process of FIG. 11 is illustrated.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The dimensions of each member shown in the drawings may differ from the actual dimensions of each member for convenience of explanation. Also, in the drawings, an arrow U indicates the upward direction of the illustrated structure. Arrow D indicates the downward direction of the illustrated structure. Arrow F indicates the forward direction of the illustrated structure. Arrow B indicates the rearward direction of the illustrated structure. Arrow L indicates the left direction of the illustrated structure. Arrow R indicates the right direction of the illustrated structure. These directions are relative directions set for the vehicle lamp 20 shown in FIG.

1 and 2 are schematic diagrams illustrating the configuration of a transparent resin cover 10 for vehicles according to this embodiment. As illustrated in FIG. 3, the transparent resin cover 10 is used as an outer cover for a vehicle lamp 20 (an example of a lamp unit) such as a headlamp. Specifically, the transparent resin cover 10 is arranged to block the opening of the lamp body 21 from the front. A lamp chamber is formed between the lamp body 21 and the transparent resin cover 10 . The light emitted from the light source 22 arranged in the lamp chamber passes through the transparent resin cover 10 and is irradiated forward of the vehicle. The light source 22 is a light emitting diode or the like. Note that the transparent resin cover 10 may be used as an outer cover for other vehicle lamps such as fog lamps and rear lamps, in addition to the headlamps.

As illustrated in FIGS. 1 and 2, the transparent resin cover 10 includes a resin molding 11 and metal wires 12. The resin molded body 11 has a predetermined shape corresponding to the shape of the transparent resin cover 10 . The resin molding 11 is made of, for example, polycarbonate resin, acrylic resin, PET resin, PBT resin, polyimide resin, or other transparent resin. The term "transparent" used in this specification includes colorless transparency and colored transparency. The term "transparent" does not only refer to a material that completely transmits light, but also includes a material that is semi-transparent to the extent that the object on the opposite side of the resin molded body 11 can be visually recognized.

The metal wire 12 functions as a heater that heats the transparent resin cover 10 . The metal wire 12 is, for example, copper wire, nickel wire, nichrome wire, silver wire, iron wire, or other conductive wire. As the metal wire 12, a metal wire having a thickness that does not affect the distribution of light transmitted through the transparent resin cover 10 while preventing disconnection is used. Metal wire 12 has a diameter of, for example, 0.05 mm to 0.5 mm.

The metal wire 12 has a heater wiring portion 121 and a terminal portion 122 . The heater wiring portion 121 is a portion that generates heat when energized, and can be made of a nichrome wire or the like. As illustrated in FIG. 1, the heater wiring portion 121 has a plurality of first wire portions 121a and a plurality of second wire portions 121b. In this example, the plurality of first line portions 121a extend in the horizontal direction (an example of the first direction), and the plurality of second line portions 121b extend in the vertical direction (an example of the second direction). The plurality of second line portions 121b are shorter than the plurality of first line portions 121a and connect the adjacent

first line portions

121a, 121a.

As illustrated in FIG. 2, the heater wiring portion 121 is embedded in the resin molding 11. As shown in FIG. For example, when the thickness T1 of the resin molded body 11 is 3 to 5 mm, the thickness T2 from the front surface 111 of the resin molded body 11 to the heater wiring portion 121 is 0.01 to 2 mm.

The terminal portion 122 is exposed from the outside of the resin molded body 11 (transparent resin cover 10). Specifically, the terminal portion 122 is exposed on the rear surface 112 of the resin molded body 11 and is supplied with electric power by a power supply portion (not shown) arranged in the vehicle.
When power is supplied to the heater wiring portion 121 through the terminal portion 122, the heater wiring portion 121 generates heat, and the temperature of the portion of the resin molded body 11 where the heater wiring portion 121 is arranged rises. As a result, the snow adhering to the front surface of the transparent resin cover 10 is melted, and the fogging occurring on the rear surface of the transparent resin cover 10 is also eliminated.

Next, a method for manufacturing the transparent resin cover 10 will be described with reference to FIGS. 4 to 10. FIG. In this example, a method of forming the transparent resin cover 10 by two-color molding, that is, injection molding twice will be described.

As exemplified in FIGS. 5 and 6, first, the metal wire 12 is fixed to the first mold 31 along a plurality of guide pins 311 provided on the first mold 31 (STEP 1 in FIG. 4). : metal wire fixing process). In this example, as illustrated in FIG. 5 , the metal wire 12 is fixed to the first mold 31 while being in close contact with the first surface 31A of the first mold 31 .

A plurality of guide pins 311 are appropriately provided at locations corresponding to positions where the metal wires 12 are arranged. A plurality of guide pins 311 protrude from the first surface 31A of the first mold 31 toward the second mold 32 . For example, the metal wire 12 is routed from the second surface 31B of the first mold 31 to the first surface 31A side via the through hole 312, and is hooked on the guide pin 311 or run along the first metal wire 12. It is wired to a predetermined position inside the mold 31 . The end portion 12E of the metal wire 12 is inserted into the through hole 312 of the first mold 31 without being wired on the first surface 31A side. The number and arrangement of guide pins 311 are not limited to the number and arrangement shown in FIGS. The number and arrangement of the guide pins 311 can be appropriately changed depending on the arrangement of the metal wires 12, the viscosity of the resin injected into the mold, the injection direction, the injection pressure, and the like.

Subsequently, as illustrated in FIG. 7, the first mold 31 and the second mold 32 are brought into contact with each other to form the first cavity C1 (STEP 2 in FIG. 4: first cavity forming step). Then, the molten first transparent resin R1 is injected into the first cavity C1. For example, as shown in FIG. 7, an injection path 321 for the first transparent resin R1 is formed in the second mold 32, and the first transparent resin R1 passes through the injection path 321 into the first cavity C1. injected into Then, the first transparent resin R1 is cured in the first cavity C1 to form the resin body 11A having the metal wires 12 (STEP 3 in FIG. 4: resin body forming step).

Subsequently, the first mold 31 is separated from the second mold 32 while holding the resin body 11A. In this example, since the metal wire 12 is in close contact with the first surface 31A of the first mold 31, the resin body 11A with the metal wire 12 exposed is formed as illustrated in FIG. be. Since the end 12E of the metal wire 12 is inserted into the through hole 312 of the first mold 31, the end 12E of the metal wire 12 is exposed from the resin body 11A as illustrated in FIG. are doing.

Then, as illustrated in FIG. 9, the second mold 32 and the third mold 33 are brought into contact with each other to form the second cavity C2 (STEP 4 in FIG. 4: second cavity forming step). Specifically, as illustrated in FIG. 8, the second mold 32 is inverted after the first mold 31 is separated, and as illustrated in FIG. The third mold 33 is brought into contact with. In this example, the metal wire 12 exposed from the resin body 11A is exposed inside the second cavity C2. Further, the tip 12E1 of the end 12E of the metal wire 12 exposed from the resin body 11A is inserted into the recess 331 provided in the third mold 33 and held.

Subsequently, the molten second transparent resin R2 is injected into the second cavity C2. For example, as shown in FIG. 9, an injection path 332 for the second transparent resin R2 is formed in the third mold 33, and the second transparent resin R2 is injected from the injection path 332 into the second cavity C2. be. As the second transparent resin R2, the same resin as the first transparent resin R1 is used. In this example, the metal wire 12 exposed in the second cavity C2 is covered with the second transparent resin R2. At this time, a hole corresponding to the guide pin 311 is formed in the resin body 11A, and the hole is filled with the second transparent resin R2.

Then, the resin molding 11 is formed by curing the second transparent resin R2 in the second cavity C2. As illustrated in FIG. 10, the resin molded body 11 is removed from the second mold 32 and the third mold 33, and the transparent resin cover 10 having the metal wires 12 is formed (STEP 5 in FIG. 4: transparent resin cover 10). cover forming step). In this example, the transparent resin cover 10 is formed in which the tip 12E1 of the end 12E of the metal wire 12 is exposed.

In the above-described manufacturing method, when the first transparent resin R1 is injected into the first cavity C1, the first transparent resin R1 flows through the first cavity C1 while flowing through the metal placed in the first cavity C1. contact line 12; At this time, the metal wire 12 is pushed by the flow of the first transparent resin R1, and the arrangement of the metal wire 12 may be shifted from the initial state. However, since the metal wire 12 is arranged along the guide pin 311, even if the metal wire 12 is pushed by the flow of the first transparent resin R1, the guide pin 311 functions as a stopper. Displacement can be suppressed. In addition, since the metal wire 12 is fixed to the first mold 31 while being hooked on the guide pin 311 and given a certain amount of tension, it is possible to suppress the movement of the metal wire 12 due to the flow of the first transparent resin R1. As a result, it is possible to suppress misalignment of the metal wires 12 when injecting the first transparent resin R1, and to manufacture the transparent resin cover 10 in which the metal wires 12 are arranged in a desired shape.

In addition, in the transparent resin cover forming step, the metal wires 12 exposed from the resin body 11A are covered with the second transparent resin R2, so that the metal wires 12 except for the terminal portions 122 are completely covered with the transparent resin. state. That is, the metal wires 12 are not exposed on the front surface 111 of the transparent resin cover 10, and the front surface 111 is smooth. Since the metal wire 12 is not exposed in this manner, the metal wire 12 can be shielded from oxygen and moisture to prevent deterioration.
Moreover, if the metal wire 12 is exposed from the front surface 111 of the transparent resin cover 10, the front surface 111 may be uneven, which may refract the emitted light or cause distortion of the field of view. However, since the front surface 111 is smooth as described above, it is possible to prevent refraction of light emitted from the front surface 111 and distortion of the field of view. Furthermore, since the front surface 111 is smooth, a protective layer such as a hard coat can be easily applied to the front surface 111 of the transparent resin cover 10 .

Also, in the step of forming the transparent resin cover, the tip 12E1 of the end 12E of the metal wire 12 exposed from the resin body 11A is held by the third mold 33. That is, since the tip 12E1 of the end 12E of the metal wire 12 is not embedded in the second transparent resin R2, it can be used as the terminal portion 122 of the metal wire. 2 may be formed by deforming the tip 12E1 of the metal wire 12 exposed from the resin molded body 11 along the surface of the resin molded body 11, for example.

Note that, in the above embodiment, different resins may be used for the first transparent resin R1 and the second transparent resin R2.

5 and 6, in the resin body forming step, the first transparent resin R1 intersects the wiring direction of the metal wire 12 (longitudinal direction of the first wire portion 121a of the metal wire 12). It is injected into the first cavity C1 along the direction (arrow F1 in FIG. 6). However, the first transparent resin R1 may be injected in a direction along the wiring direction of the metal wires 12 (arrow F2 in FIG. 6). In this case, the first transparent resin R1 flows in the wiring direction of the metal wire 12 (longitudinal direction of the first wire portion 121a of the metal wire 12). At this time, compared to the case where the first transparent resin R1 is injected from the direction of the arrow F1 in FIG. It is less affected by the flow of R1. Therefore, it is possible to suppress the displacement of the metal wires 12 due to the flow of the first transparent resin R1.

Also, in the above embodiment, the method of forming the transparent resin cover 10 by two-color molding has been described. However, the transparent resin cover 10 may be formed by single-color molding, that is, one-time injection molding. The process of forming by one injection molding will be described below with reference to FIGS. 11 to 14 .

First, as illustrated in FIG. 12, the metal wire 12 is fixed to the first mold 41 along the plurality of guide pins 411 provided on the first mold 41 (STEP 11 in FIG. 11: metal wire fixing process). A plurality of guide pins 411 are appropriately provided at positions corresponding to the positions where the metal wires 12 are arranged, similarly to the guide pins 311 in FIG. It protrudes toward the mold 42 . The metal wire 12 is fixed to the first mold 41 while being separated from the first surface 41A of the first mold 41 . For example, the guide pin 411 may be provided with a protrusion that holds the metal wires 12 in a spaced apart state.

Subsequently, as illustrated in FIG. 13, the first mold 41 and the second mold 42 are brought into contact with each other to form a cavity C (STEP 12 in FIG. 11: cavity forming step). In this example, the tip 12E1 of the metal wire 12 is bent, and the cavity C is formed so that the tip 12E1 contacts the first surface 42A of the second mold 42 .

Then, the molten transparent resin R is injected into the cavity C. For example, as shown in FIG. 13, an injection path 412 for the transparent resin R is formed in the first mold 41 , and the transparent resin R is injected into the cavity C via the injection path 412 . Although the transparent resin R is injected into the cavity C from the first surface 41A of the first mold 41, for example, it is injected in a direction along the wiring direction of the metal wire 12 (longitudinal direction of the first wire portion 121a). may be

Then, the transparent resin R is cured within the cavity C to form the resin molded body 11 . As illustrated in FIG. 14, the resin molding 11 is removed from the first mold 41 and the second mold 42, and the transparent resin cover 10 having the metal wires 12 is formed (STEP 13 in FIG. 11: transparent resin cover 10). cover forming step).

Also in this manufacturing method, since the metal wires 12 are arranged along the guide pins 411, it is possible to prevent the metal wires 12 from being displaced when the transparent resin R is injected. Thereby, the transparent resin cover 10 in which the metal wire 12 is laid in a desired shape can be manufactured.

The holes corresponding to the guide pins 411 formed in the resin molding 11 may be filled with the same transparent resin as the transparent resin R.

Although the embodiments of the present disclosure have been described above, it goes without saying that the technical scope of the present invention should not be construed to be limited by the description of the embodiments. It should be understood by those skilled in the art that this embodiment is merely an example, and that various modifications of the embodiment are possible within the scope of the invention described in the claims. The technical scope of the present invention should be determined based on the scope of the invention described in the claims and their equivalents.

In an embodiment in which the transparent resin cover 10 is formed by two-color molding, the tip 12E1 of the metal wire 12 exposed from the resin body 11A is inserted into the recess 331 of the third mold 33 as illustrated in FIG. However, for example, as illustrated in FIG. 13, the terminal portion 122 illustrated in FIG. 2 is formed by bringing the tip 12E1 of the metal wire 12 into contact with the surface of the third mold 33 in a bent state. may

In an embodiment in which the transparent resin cover 10 is formed by single-color molding, the tip 12E1 of the metal wire 12 is in contact with the first surface 42A of the second mold 42 in a bent state as illustrated in FIG. However, as illustrated in FIG. 9, a recess into which the tip 12E1 of the metal wire 12 is inserted may be formed in the second mold 42. FIG.

An example in which the transparent resin cover 10 is used as an outer cover for the vehicle lamp 20, which is a lamp having a single function such as a headlamp, has been described. However, the transparent resin cover 10 can be used as an outer cover of a lamp unit in which a plurality of lamps with different functions are arranged in the lamp chamber, such as a rear combination lamp having a stop lamp and a turn signal lamp. Alternatively, the transparent resin cover 10 can be used as an outer cover for a sensor-equipped vehicle lamp having a sensor such as a camera (23 in FIG. 3) and a headlamp.

Also, the transparent resin cover 10 may be used as an outer cover for a sensor unit that is mounted on the vehicle and acquires information around the vehicle instead of the lamp unit. In this case, for example, when the sensor of the sensor unit acquires information about the surroundings of the vehicle through the transparent resin cover, it is possible to prevent normal detection by the sensor due to snow or cloudiness adhering to the cover.

This application is based on Japanese Patent Application No. 2021-129681 filed on August 6, 2021, the contents of which are incorporated herein by reference.

Claims

A method for manufacturing a transparent resin cover for a vehicle having a metal wire for a heater, comprising:
a step of fixing the metal wire to the first mold along a plurality of guide pins provided on the first mold;
contacting the second mold and the first mold to form a cavity;
A method of manufacturing a transparent resin cover for a vehicle, comprising: injecting a molten transparent resin into the cavity and curing the transparent resin within the cavity to form the transparent resin cover having the metal wire. .
A method for manufacturing a transparent resin cover for a vehicle having a metal wire for a heater, comprising:
a metal wire fixing step of fixing the metal wire to the first mold along a plurality of guide pins provided on the first mold;
a first cavity forming step of forming a first cavity by bringing the second mold and the first mold into contact with each other;
a resin body forming step of injecting a molten first transparent resin into the first cavity and curing the first transparent resin in the first cavity to form a resin body having the metal wire;
A second cavity forming step of separating the first mold from the second mold while holding the resin body, and bringing the second mold and the third mold into contact with each other to form a second cavity. and,
a transparent resin cover forming step of injecting a molten second transparent resin into the second cavity and curing the second transparent resin in the second cavity to form the transparent resin cover having the metal wire; A method for manufacturing a transparent resin cover for a vehicle, comprising:
In the metal wire fixing step, the metal wire is brought into close contact with the surface of the first mold,
forming the second cavity in the second cavity forming step so that the metal wire exposed from the resin body is exposed in the second cavity;
3. The method of manufacturing a transparent resin cover for a vehicle according to claim 2, wherein said metal wire exposed in said second cavity is covered with said second transparent resin in said transparent resin cover forming step.
the metal wire has a terminal portion exposed to the outside of the transparent resin cover,
In the resin body forming step, the molten first transparent resin is injected into the first cavity with one end of the metal wire exposed from the first cavity, and the one end of the metal wire is exposed. forming the resin body;
In the step of forming the transparent resin cover, the molten second transparent resin is injected into the second cavity while the tip of the one end portion of the metal wire exposed from the resin body is held by the third mold. 4. The method of manufacturing a transparent resin cover for a vehicle according to claim 3, wherein the terminal portion is formed.
The metal wire includes a plurality of first wire portions extending in a first direction and a plurality of second wire portions connecting the adjacent first wire portions and extending in a second direction intersecting the first direction. have
The first line portion is longer than the second line portion,
The method for manufacturing a transparent resin cover for vehicles according to any one of claims 2 to 4, wherein said first transparent resin is injected in a direction along said first direction.
The method for manufacturing a transparent resin cover for vehicles according to any one of claims 1 to 5, wherein the transparent resin cover for vehicles is a cover for a lamp unit.
The method for manufacturing a transparent resin cover for vehicles according to any one of claims 1 to 5, wherein the transparent resin cover for vehicles is a cover for a sensor unit.