KR102614109B1 - Airbag cover assembly and manufacturing method thereof - Google Patents

Abstract

It relates to an airbag cover assembly and a method of manufacturing the same, comprising an airbag cover coupled to a steering wheel and a lighting emblem module installed inside the airbag cover and irradiating light to the outside of the airbag cover to illuminate the emblem, the lighting The emblem module includes a printed circuit board on which a plurality of LEDs are installed, a bracket that secures the printed circuit board to the lower surface of the upper plate of the airbag cover, and a housing on which the printed circuit board is seated and fixed by being coupled to the bracket. By preparing the configuration, the bracket can be molded integrally with the airbag cover, and the printed circuit board and housing coupled to the airbag cover can be firmly fixed using the bracket.

Description

Airbag cover assembly and manufacturing method thereof {AIRBAG COVER ASSEMBLY AND MANUFACTURING METHOD THEREOF}

The present invention relates to an airbag cover assembly, and more specifically, to an airbag cover assembly coupled to a steering wheel of a vehicle and having an emblem installed on its upper surface, and a method of manufacturing the same.

Driver's seat airbag devices applied to automobiles are widely used to protect passengers in the driver's seat from shock that occurs during a car collision.

Such a driver's seat airbag device is generally mounted on a steering wheel and includes an inflator, an airbag cushion, a housing that accommodates the airbag cushion in a folded state, and a cover that covers an opening of the housing.

When a car crashes, the airbag cushion expands as gas is injected from the inflator, and the cover made of soft resin ruptures due to the inflation force of the airbag cushion, forming an opening in the cover, which is inflated toward the vehicle's passengers through the opening.

This driver's seat airbag device may be equipped with a cover having a decorative plate, so-called emblem.

For example, patent document 1 and patent document 2 below disclose airbag cover technology.

Meanwhile, emblems are generally made with a company's design or mark, and have the function of giving value to the vehicle represented by the emblem rather than simply indicating the manufacturing company.

Emblems are installed throughout the exterior and interior of a vehicle to reveal the credit value accumulated in the emblem. The location where these emblems are installed varies depending on the company that manufactures the vehicle, but most are installed on the rear of the vehicle and the front of the steering wheel.

That is, it is installed on the airbag cover that covers the armature installed in the center of the steering wheel steered by the passenger driving the vehicle.

Generally, an emblem without an illumination function is applied to an airbag cover according to the prior art.

Accordingly, the airbag cover according to the prior art can be identified by natural light during the day, but at night, as the amount of light becomes insufficient, identification becomes difficult, so there is a problem in that it does not function properly due to difficulty in identification.

In order to solve this problem, technology for applying lighting to the emblem has been developed in Patent Documents 3 to 5 above, but the structure has become complicated due to the addition of new components such as LEDs, substrates, housings, and diffusion plates, and manufacturing There was a problem with costs rising unnecessarily.

Additionally, the airbag cover according to the prior art had a structure in which the emblem and the lighting module were combined on both sides around the airbag cover, making assembly work difficult and workability deteriorating.

Meanwhile, the driver's seat airbag device deploys the airbag cushion using nitrogen gas generated by instantaneously burning a gas generator such as sodium nitrite by an inflator during a car collision.

However, when manufacturing the emblem using a metal material, there was a problem in that the emblem attached to the airbag cover detached from the airbag cover when the airbag cushion was deployed, causing injury to the driver.

In other words, the emblem made of metal material requires additional riveting work, etc. to remain firmly attached to the airbag cushion, which reduces workability and increases work time and manufacturing cost, and the airbag with the emblem installed There was a problem of increasing the weight of the cover.

Republic of Korea Patent Registration No. 10-1718689 (announced on March 22, 2017) Republic of Korea Patent Registration No. 10-2005738 (announced on July 31, 2019) Republic of Korea Patent Registration No. 10-1076195 (announced on October 26, 2011) US Patent No. US 8,925,959 (January 6, 2015) US Patent No. US 8,061,861 (November 22, 2011)

The purpose of the present invention is to solve the problems described above and to provide an airbag cover assembly that can improve visibility by illuminating an emblem installed on the airbag cover.

Another object of the present invention is to provide an airbag cover assembly and a manufacturing method thereof that can firmly couple an airbag cover and a lighting emblem so that the lighting emblem module is not separated from the airbag cushion when the airbag cushion is inflated.

Another object of the present invention is to provide an airbag cover assembly and a manufacturing method thereof that can shorten work time and improve workability by improving the coupling structure between the airbag cover and the lighting emblem module.

Another object of the present invention is to provide an airbag cover assembly that can provide various information transmission functions by selectively lighting or flashing a plurality of LEDs and a method of manufacturing the same.

In order to achieve the above-mentioned object, the airbag cover assembly according to the present invention includes an airbag cover coupled to the steering wheel and an illumination emblem installed inside the airbag cover and illuminating the airbag cover with an emblem by irradiating light to the outside. It includes a module, wherein the lighting emblem module includes a printed circuit board on which a plurality of LEDs are installed, a bracket for fixing the printed circuit board to the lower surface of the upper plate of the airbag cover, and the printed circuit board is seated on the upper surface and coupled to the bracket. It includes a housing that is fixed to the housing, and the bracket is manufactured integrally with the airbag cover.

In addition, in order to achieve the above-mentioned object, the manufacturing method of the airbag cover assembly according to the present invention includes the steps of (a) manufacturing the airbag cover and the bracket as one piece, (b) a printed circuit with a plurality of LEDs installed on the bracket. Combining the substrate and the housing and (c) fixing the housing by bending a plurality of fixing tabs provided on the bracket.

As described above, according to the airbag cover assembly and its manufacturing method according to the present invention, a bracket is integrally molded with the airbag cover using an insert injection molding method, and a substrate and housing coupled to the rear of the airbag cover using the bracket are formed. The effect of being able to firmly fix is obtained.

Accordingly, according to the present invention, by firmly combining the airbag cover and the lighting emblem module to prevent the lighting emblem module from being separated from the airbag cover when the airbag cushion is inflated and deployed, injury to the occupants caused by the lighting emblem module can be prevented in advance. You can.

That is, according to the present invention, the bracket that requires rigidity in the lighting emblem module is manufactured from a metal material, and the remaining parts are manufactured from a synthetic resin material to minimize the load on the lighting emblem module, thereby manufacturing the lighting coupled to the airbag cover. The effect of preventing injury to occupants due to the lighting emblem module is achieved by preventing separation and separation of the emblem module.

In addition, according to the present invention, the effect of maximizing the lighting effect is obtained by lighting or blinking a plurality of LEDs installed on the rear of the airbag cover in various colors.

In addition, according to the present invention, the effect of being able to provide various information transmission functions by selectively lighting or blinking a plurality of LEDs is obtained.

1 is a front view of an airbag cover assembly according to a preferred embodiment of the present invention;
Figure 2 is a rear view of the airbag cover shown in Figure 1;
Figure 3 is an exploded perspective view of the lighting emblem module in Figure 1;
Figure 4 is a cross-sectional view taken along line AA' shown in Figure 1;
5 is a process diagram illustrating step by step the manufacturing method of the airbag cover assembly according to a preferred embodiment of the present invention;
Figures 6 to 9 are diagrams illustrating each process shown in Figure 5;
10 is a perspective view of an airbag cover assembly according to another embodiment of the present invention;
Figure 11 is an exploded perspective view of the lighting emblem shown in Figure 10;
Figure 12 is a cross-sectional view taken along line CC' shown in Figure 10.

Hereinafter, an airbag cover assembly and a manufacturing method thereof according to a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

Figure 1 is a front view of an airbag cover assembly according to a preferred embodiment of the present invention, Figure 2 is a rear view of the airbag cover shown in Figure 1, Figure 3 is an exploded perspective view of the lighting emblem module in Figure 1, and Figure 4 is an exploded perspective view of the lighting emblem module in Figure 1. This is a cross-sectional view taken along line A-A' shown in Figure 1.

Hereinafter, the direction toward the hub of the steering wheel based on the airbag cover 11 is referred to as 'rear', and the opposite direction is referred to as 'forward'. And terms indicating directions such as 'left', 'right', 'upward' and 'downward' refer to each direction based on the 'front' and 'rear' as shown in each drawing. define.

As shown in FIGS. 1 to 4, the airbag cover assembly 10 according to a preferred embodiment of the present invention is installed inside the airbag cover 11 and the airbag cover 11 coupled to the steering wheel, and includes an airbag cover ( It includes a lighting emblem module (hereinafter abbreviated as 'lighting module') 12 that irradiates light to the outside of 11) and illuminates the emblem.

The airbag cover 11 shields the side wall 21 and the top of the side wall 21 coupled to the airbag housing installed on the steering wheel (not shown) and covers the airbag module disposed on the armature of the steering wheel (not shown). It includes an upper plate 22 covering the face).

The side wall portion 21 is coupled to the airbag housing and modularized into an airbag module, and the airbag module can be combined into a structure disposed on a steering wheel.

That is, the side wall portion 21 may be formed in a cylindrical shape with a cross-section of various shapes such as a circular shape, an oval shape, or a square shape, so as to correspond to the coupling space formed in the airbag housing. A lower cover (not shown) that shields the lower surface of the side wall portion 21 may be coupled to the lower portion of the side wall portion 21.

A leather cover may be installed on the upper surface of the upper plate 22.

In addition, the upper plate 22 has a tear line 23 that breaks as the airbag cushion expands and deploys, and a plurality of transmission holes 24 that transmit the light emitted from the plurality of LEDs 31 provided in the lighting module 12. This can be formed.

The tear line 23 may be formed in an approximately 'H' shape along the central portion of the upper plate 22 and both side walls 21.

A plurality of coupling protrusions 25 coupled to a plurality of through holes 62 formed in the diffuser 60 may be formed on the rear surface of the upper plate 22 to protrude.

The lighting module 12 is a printed circuit board (hereinafter abbreviated as 'board') 30 on which a plurality of LEDs 31 are installed, and the board 30 is fixed to the lower surface of the upper plate 22 of the airbag cover 11. It includes a bracket 40 and a housing 50 on which the substrate 32 is seated and coupled to the bracket 40 and fixed thereto.

In addition, the lighting module 12 is installed between the substrate 30 and the bracket 40, and a diffuser 60 diffuses the light emitted from each LED 31 and limits the movement path so that it does not cross and mix with each other. ) may further be included.

The substrate 30 is formed in a substantially plate shape, and a plurality of LEDs 31, for example, four, may be installed on the front surface of the substrate 30. Of course, the number of LEDs 31 is not limited to four, and one to three, or five or more may be provided, and may be arranged on the substrate 30 according to various conditions such as the shape and size of the lighting module 12. The number, location, and shape of LEDs 31 can be changed in various ways.

This substrate 30 may be coupled to the bracket 40 while being seated in the seating space S formed on the front of the housing 50.

And a diffuser 60 disposed between the upper plate 11 and the front side of the substrate 30 may be coupled.

In addition, a connector 32 that transmits power and control signals to each LED 31 may be provided on the back of the substrate 30.

Meanwhile, in FIG. 3, the bracket 40 is shown separated from the airbag cover 11, but the bracket 40 is molded integrally with the upper plate 22 by insert injection molding when manufacturing the airbag cover 11. It can be.

In detail, the bracket 40 may include a plate portion 41 formed in a substantially plate shape and a plurality of fixing tabs 42 extending rearward from the edge of the plate portion 42.

The bracket 40 is made of a rigid metal material such as aluminum or steel, and the plate portion 41 is made of a synthetic resin material. When manufacturing the airbag cover 11, the bracket 40 is made of a rigid metal material such as aluminum or steel. It can be molded integrally with the upper plate 22.

A plurality of penetration holes may be formed in this plate portion 41 at positions corresponding to the plurality of penetration holes 24 formed in the upper plate 11.

A plurality of fixing tabs 42 may be provided along the edge of the plate portion 41 and spaced apart from each other.

For example, when viewed in FIG. 3, two fixing tabs 42 are provided on the upper side of the plate portion 41, three are provided on the lower side of the plate portion 41, and one is provided on both sides of the plate portion 41. A total of 7 can be provided.

Of course, the present invention is not necessarily limited to this, and the size, number, and installation position of the fixing tabs 42 and each fixing tab 42 depend on various conditions such as the shape and size of the plate portion 41 and the housing 50. The spacing between them can be adjusted in various ways.

Each fixing tab 42 may be bent to support the lower surface of the housing 50 to secure the housing 50 in which the diffuser 60 and the substrate 30 are combined.

Here, a coupling hole 43 into which the boss 52 formed on the lower surface of the housing 50 is coupled may be formed in the fixing tab 42.

The diffuser 60 is disposed between the substrate 30 and the bracket 40 and combined with the bracket, and has the function of preventing the light emitted forward from each LED 31 from intersecting and mixing with each other while being scattered at various angles. Do it.

For this purpose, the diffuser 60 is manufactured to be opaque or translucent using a synthetic resin material, and the diffuser 60 is provided with a light movement path so that the light emitted from each LED 31 is transmitted only upward. A plurality of path providing units 61, for example, four, may be formed.

The path providing unit 61 can block the light emitted from each LED 31 from scattering to the surroundings, that is, up, down, left and right.

To this end, the path providing portion 61 protrudes forward from the front of the diffuser 60 and may be coupled to each penetration hole 24 formed in the upper plate 22.

In addition, a plurality of through holes 62 may be formed in the diffuser 60 along the front-back direction and into which the plurality of coupling protrusions 25 formed on the upper plate 22 are coupled.

The housing 50 is combined with the bracket 40 and functions to fix the substrate 30 seated in the seating space S formed on the front side.

This housing 50 is formed in an approximately hexahedral shape with the front open so as to form the seating space S, and a plurality of seven fixing tabs 42 are provided on the bracket 40 on the rear of the housing 50. A plurality of fixing groove portions 51 that are fixed in a bent state may be provided.

Each fixing groove 51 is formed to be concavely recessed from each side of the housing 50 toward the center, and each fixing tab 42 is bent and coupled to the coupling hole 43 in each fixing groove 51. The boss 52 may be formed to protrude downward.

In addition, a pair of fixing ribs 53 may be formed to protrude on both sides of each fixing groove 51, respectively, for fixing the bent fixing tabs 42.

Therefore, each fixing tab 42 is bent to come into close contact with each fixing groove 51 formed in the housing 50, and each boss 52 is coupled to the coupling hole 43 formed in each fixing tab 42. It can be joined to the fixing tab 42 by melting it by high-temperature heat using a welding or thermal fusion method and expanding it to an area larger than the area of the coupling hole 43.

As such, the present invention can provide a lighting emblem effect by installing a lighting emblem module including a plurality of LEDs on an airbag cover and lighting or flashing the plurality of LEDs in various colors.

Next, a method of manufacturing an airbag cover assembly according to a preferred embodiment of the present invention will be described in detail with reference to FIGS. 5 to 9.

Figure 5 is a process diagram step by step explaining the manufacturing method of the airbag cover assembly according to a preferred embodiment of the present invention, and Figures 6 to 9 are diagrams illustrating each process shown in Figure 5.

In step S10 of FIG. 5, the operator places the bracket 40 inside a mold for molding the airbag cover 11 and injects raw materials into the mold to form the bracket as shown in FIG. 6 by insert injection molding. (40) and the airbag cover (11) are molded into one piece.

In step S12, the diffuser 60 is coupled to the bracket 40 inserted into the airbag cover 11. At this time, the plurality of coupling protrusions 25 formed on the upper plate 22 are each coupled to the plurality of through holes 62 formed in the diffuser 60.

In step S14, the operator combines the substrate 30 and the housing 50. At this time, the substrate 30 is seated in the seating space S formed on the front of the housing 50.

In step S16, the operator couples the housing 50 to which the substrate 30 is coupled to the bracket 40 to which the diffuser 60 is coupled, as shown in FIG. 7 .

And in step S18, each fixing tab 42 formed along the edge of the bracket 40 is bent to come into close contact with each fixing groove portion 51 provided in the housing 50 (see FIG. 8), and then each fixing groove portion 51 The boss 52 formed in is penetrated and coupled to the coupling hole 43 of each fixing tab 42. Next, the rear end of the boss 52 is heated, and the rear end of the molten boss 52 is pressed to expand to an area larger than the area of the coupling hole 43 to join the fixing tab 42 and the boss 52 ( 9). At this time, the fixing ribs 53 formed on both sides of each fixing groove 51 are heated and pressed together with the boss 52 and are joined to each bent fixing tab 42 to firmly fix each fixing tab 42. .

Through this process, the present invention can integrally mold the bracket to the airbag cover using an insert injection molding method, and use the bracket to firmly fix the substrate and housing coupled to the rear of the airbag cover.

Accordingly, the present invention firmly combines the airbag cover and the lighting emblem module to prevent the lighting emblem module from being separated from the airbag cover when the airbag cushion is inflated and deployed, thereby preventing injury to occupants caused by the lighting emblem module in advance. .

That is, the present invention manufactures the bracket that requires rigidity in the lighting emblem module with a metal material, and manufactures the remaining parts with a synthetic resin material to minimize the load on the lighting emblem module, so that the lighting emblem module coupled to the airbag cover Separation and separation can be prevented in advance, preventing injury to occupants caused by the lighting emblem module.

Additionally, the present invention can maximize the lighting effect by lighting or flashing a plurality of LEDs installed on the rear of the airbag cover in various colors.

In addition, the present invention can provide various information transmission functions by selectively lighting or blinking a plurality of LEDs.

For example, if a fault condition is diagnosed as a result of the diagnosis of devices installed in the vehicle, the control unit provided in the vehicle may provide a warning function by lighting or flashing all or part of the LEDs in a specific color, such as red.

In addition, when the present invention is applied to an electric vehicle, the control unit may display the charging state by lighting or flashing some or all of the plurality of LEDs in a specific color, for example, green, to correspond to the charging state of the battery.

Of course, the present invention is not necessarily limited to this, and sets scenarios for lighting or flashing a plurality of LEDs in various colors, and selectively lights or flashes to correspond to the set scenario according to the actual operating state of the car to provide various information. It may also provide a forwarding function.

Meanwhile, in this embodiment, it has been described that the housing is fixed by bending a plurality of fixing tabs provided on the bracket, but the present invention is not necessarily limited thereto.

Next, the configuration of an airbag cover assembly according to another embodiment of the present invention will be described in detail with reference to FIGS. 10 to 12.

FIG. 10 is a perspective view of an airbag cover assembly according to another embodiment of the present invention, FIG. 11 is an exploded perspective view of the lighting emblem shown in FIG. 10, and FIG. 12 is a cross-sectional view taken along line C-C' shown in FIG. 10.

The airbag cover assembly 10 according to another embodiment of the present invention, as shown in FIGS. 10 to 12, is the same as the configuration of the airbag cover assembly 10 described with reference to FIGS. 1 to 4, except that it includes a bracket ( Some of the plurality of fixing tabs formed in 40) are changed into hook shapes to fix the housing 50.

In FIG. 11, the bracket 40 is shown separated from the airbag cover 11, but the bracket 40 is molded integrally with the upper plate 22 by insert injection molding when manufacturing the airbag cover 11.

A fixing tab 42 and a hook portion 44 for fixing the housing 50 may be provided at the edge of the bracket 40.

For example, as seen in FIG. 11, a pair of fixing tabs 42 are provided on the upper side of the plate portion 41 of the bracket 40, and one hook portion 44 is provided on both sides of the plate portion 41. In addition, three hook parts 44 may be provided on the lower side of the plate part 41.

Each hook portion 44 functions to fix the housing 50 by being hung on a hanging member 54 installed on the housing 50.

For this purpose, the hook portion 44 is formed to extend backward from the plate portion 44, and a hanging groove is formed on one surface of the hook portion 44 in contact with the hanging member 54 into which the hanging member 54 is inserted. You can.

Additionally, a hanging member 54 may be installed along the edge of the housing 50.

The hanging member 54 is formed into a bar shape using a durable metal material such as aluminum or steel or a synthetic resin material so that the cross-section has an approximately '└┘' shape when viewed in FIG. 11, and both ends are upwardly oriented. It can be manufactured by bending.

This hanging member 54 may be inserted into both sides and the lower edge of the housing 50, or may be manufactured integrally with the housing 50 by insert injection molding when manufacturing the housing 50.

In addition, the housing 50 includes a pair of fixing groove portions 51 to which a pair of fixing tabs 42 are fixed, and five hook portions 55 to which five hook portions 44 are caught on the hanging member 54. ) can be provided.

A boss 52 is provided in each fixing groove 51, and a fixing rib 53 is provided around the boss 52, for example, on both sides and below the boss 52, to fix the bent fixing tab 42. It can be formed into a 'U' shape.

Each hanging groove 55 may be concavely recessed toward the center of the housing 50 so that the hanging member 54 is exposed to the outside of the housing 50.

Therefore, when the housing 50 and the bracket 40 are combined, each fixing tab 42 is coupled with the boss 52 of each fixing groove 51, and each hook part 44 is connected to each hanging groove part 55. It may be caught on the hanging member 54 exposed to the outside of the housing 50.

In this way, according to the present invention, a hanging member can be installed on a housing, and a plurality of hooks provided on a bracket can be hung on the hanging member to firmly fix the housing and the bracket.

Accordingly, the present invention firmly combines the airbag cover and the lighting emblem module to prevent the lighting emblem module from being separated from the airbag cover when the airbag cushion is inflated and deployed, thereby preventing injury to occupants caused by the lighting emblem module in advance. .

In addition, the present invention minimizes the number of fixing tabs provided at the edge of the bracket, shortening the time required for bending and joining the fixing tabs, and improving workability.

Although the invention made by the present inventor has been described in detail according to the above-mentioned embodiments, the present invention is not limited to the above-described embodiments and, of course, can be changed in various ways without departing from the gist of the invention.

The present invention is applied to an airbag cover assembly technology that illuminates with an emblem by installing a lighting emblem module with a plurality of LEDs on the lower part of the airbag cover.

10: Airbag cover assembly
11: Airbag cover 12: Lighting emblem module
21: side wall 22: upper plate
23: tear line 24: through hole
25: Combined protrusion
30: substrate 31: LED
32: connector
40: bracket 41: plate part
42: fixing tab 43: coupling hole
44: Hook part
50: Housing 51: Fixing groove
52: Boss 53: Fixed rib
54: Hanging member 55: Hanging groove
60: Diffuser 61: Path provider
62: Tonggong
S: seating space

Claims (9)

Airbag cover attached to the steering wheel and
It includes a lighting emblem module that is installed inside the airbag cover and irradiates light to the outside of the airbag cover to illuminate the emblem,
The lighting emblem module includes a printed circuit board on which a plurality of LEDs are installed,
A bracket that secures the printed circuit board to the lower surface of the upper plate of the airbag cover, and
It includes a housing on which the printed circuit board is seated and fixed to the bracket,
The bracket is manufactured integrally with the airbag cover,
The bracket includes a plate portion formed in a plate shape and
It includes a fixing tab extending from an edge of the plate portion,
The fixing tabs are provided in plural numbers spaced apart from each other,
The bracket includes a plurality of hook portions extending along an edge,
The housing includes a hanging member installed along the edge and
It includes a plurality of hanging grooves that are concavely recessed toward the inside of the housing,
An airbag cover assembly, wherein each hook part is caught by the hanging member exposed to the outside of the housing by each hanging groove part to fix the housing. According to paragraph 1,
It is installed between the printed circuit board and the bracket, and further includes a diffuser that diffuses the light emitted from each LED and restricts the movement path to prevent them from crossing and mixing,
The diffuser is an airbag cover assembly, characterized in that a plurality of path providing parts are formed to provide a movement path for light emitted from each LED. According to paragraph 2,
The diffuser is formed with a hole through which the coupling protrusion formed on the upper plate is coupled,
An airbag cover assembly, wherein the plurality of path providing portions extend toward the upper plate so as to be coupled to a plurality of penetration holes formed in the upper plate. delete According to paragraph 2,
The housing is provided with a plurality of fixing grooves for fixing the plurality of fixing tabs provided on the bracket in a bent state,
In each fixing groove, a boss that is inserted into the coupling hole formed in each fixing tab protrudes,
An airbag cover assembly, characterized in that the boss is joined to the fixing tab bent by heating and pressurizing. delete In the method of manufacturing the airbag cover assembly according to any one of claims 1 to 3 and 5,
(a) manufacturing the airbag cover and bracket integrally,
(b) combining a printed circuit board with a plurality of LEDs installed on the bracket and a housing, and
(c) fixing the housing by bending a plurality of fixing tabs provided on the bracket,
A method of manufacturing an airbag cover assembly, wherein in step (c), the hook provided on the bracket is caught by a hanging member installed along an edge of the housing to secure the housing. In clause 7,
(d) an airbag cover assembly further comprising the step of coupling a diffuser between the bracket and the printed circuit board to limit the movement path by diffusing the light emitted from each LED to prevent them from crossing and mixing with each other. Manufacturing method. delete

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