CN107394033A - LED filament manufacturing process and LED filament - Google Patents

Abstract

The invention provides an LED filament manufacturing process and the LED filament, which relate to the field of lighting appliances. The LED filament manufacturing process includes: opening through holes at the positive and negative terminals of the substrate; passing the lead body of the LED filament through the corresponding through hole; bending the pin through the end of the through hole, and bending the pin The ends of the LED filament are pressed together to form a fixed part, so that the pins and the substrate are bonded to form a fixed part by bending the part where the pin passes through the substrate, so that the LED filament pins and the substrate are bonded more closely, and it will not occur due to high temperature and other conditions. In the case of shedding, virtual soldering, etc., the LED filament manufacturing process and LED filament provided by the present invention have a firm connection between the pin and the substrate. Even if the solder melts due to high temperature, the pin will not be separated from the substrate, so that the LED filament can work normally, thereby improving The service life of the LED filament is extended.

Description

LED filament manufacturing process and LED filament

technical field

The invention relates to the field of lighting appliances, in particular to an LED filament manufacturing process and the LED filament.

Background technique

LED (light emitting diode) is a solid-state semiconductor device that can convert electrical energy into visible light, and it can directly convert electricity into light. The field of application involves light bulbs, lamp tubes, table lamps, solar lamps, landscape lighting, household appliances and other daily household appliances. As a new type of lighting source, LED lights are favored by the people and strongly supported by the country for their remarkable characteristics of energy saving, health, environmental protection and long life.

In the prior art LED lamps, the LED filament is connected to the pins by welding. However, during the use of the LED filament, the temperature at the welding point between the LED flexible filament and the pins will continue to rise. After the temperature rises, the solder may melt, which will cause the LED filament and the pins to fall off and disconnect, making the LED filament Disconnection with other components causes the LED filament to not emit light normally, thereby reducing the service life of the LED filament.

Contents of the invention

In view of this, the purpose of the embodiments of the present invention is to provide a LED filament manufacturing process to improve the above problems.

Another object of the embodiments of the present invention is to provide an LED filament to improve the above problems.

An embodiment of the present invention provides a LED filament manufacturing process, the LED filament manufacturing process includes respectively opening through holes at the positive and negative connection ends of the substrate; passing each pin body of the LED filament through a corresponding through hole; The end of the pin body passing through the through hole is bent, and the bent end of the pin is pressed to form a fixing part, so that the pin is bonded to the substrate.

Further, the LED filament manufacturing process also includes: using a substrate to fix and package the LED chip, coating a primer on the surface of the substrate to form a primer layer, and setting a plurality of LED chips on the primer layer; The plurality of LED chips are connected in series or in parallel; the metal connection wires at both ends of the substrate are welded with tin paste or tin wire.

Further, the LED filament manufacturing process also includes: using silica gel or epoxy resin glue and fluorescent powder to mix evenly, covering the substrate and LED chips to form a sealant layer; coating and configuring the sealant layer on the sealant layer Good phosphor.

Further, the fluorescent powder includes at least one of yellow powder, red powder or green powder.

An LED filament, the LED filament is made by LED filament manufacturing process, the LED filament includes a substrate, pins and through holes, the pin includes a pin body and a fixing part, the fixing part is connected to the substrate Fitting, the part of the pin body passing through the through hole is connected to the fixing part, and the width of the fixing part is larger than the through hole.

Further, the LED filament includes a plurality of LED chips and metal connecting wires, the LED chips are arranged on the substrate, the metal connecting wires connect a plurality of LED chips in series, and the two ends of the metal connecting wires are respectively connected to the leads. The pins are electrically connected, and the LED filament also includes a sealing layer, and the sealing layer covers the substrate and the LED chip.

Further, the LED filament also includes a tin paste layer, and the LED filament is also provided with tin paste or tin wire, and the tin paste or tin wire is used for connecting metal connection wires and soldering the substrate and the pin body.

Further, the fixing part is a bent structure.

Further, the fixing part is a seven-shaped structure.

Further, the pin body is welded to the substrate.

Compared with the prior art, the present invention has the following beneficial effects:

The LED filament manufacturing process and the LED filament provided by the present invention respectively set through holes at the positive and negative connection ends of the substrate; pass the pin body of the LED filament through the corresponding through hole; bend the pin through the through hole The end portion is pressed against the bent end of the pin to form a fixed portion, and the pin is bonded to the substrate to form a fixed portion by bending the portion where the pin passes through the substrate, and the fixed portion is bonded to the substrate, In this way, the LED filament pins are more closely bonded to the substrate, and will not fall off due to high temperature, etc., and the LED filament manufacturing process and the LED filament provided by the present invention have a stable connection between the pins and the substrate, even if the high temperature causes solder Melting, the pins will not be separated from the substrate, so that the LED filament can work normally, thereby improving the service life of the LED filament.

In order to make the above-mentioned objects, features and advantages of the present invention more comprehensible, preferred embodiments will be described in detail below together with the accompanying drawings.

Description of drawings

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. The components of the embodiments of the invention generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations. Accordingly, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative technical improvements fall within the protection scope of the present invention.

Fig. 1 shows a flow chart of the LED filament manufacturing process provided by the embodiment of the present invention.

Fig. 2 shows a schematic diagram of the steps before passing the lead body of the LED filament through the corresponding through hole in the manufacturing process of the LED filament provided by the embodiment of the present invention.

Fig. 3 shows a flow chart of sealing steps of the LED filament manufacturing process provided by the embodiment of the present invention.

Fig. 4 is a schematic structural diagram of an LED filament provided by an embodiment of the present invention.

FIG. 5 is a partial structural schematic diagram of II in FIG. 4 according to an embodiment of the present invention.

Fig. 6 is a first perspective view of the LED filament provided by the embodiment of the present invention.

FIG. 7 is a schematic structural view of a substrate of an LED filament provided by an embodiment of the present invention.

FIG. 8 is a schematic structural diagram of the leads of the LED filament provided by Embodiment 1 of the present invention.

Icons: 100-LED filament; 110-substrate; 112-through hole; 113-solder paste; 120-LED chip; 130-pin; 132-pin body; 134-fixed part; Sealant layer.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. The components of the embodiments of the invention generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations. Accordingly, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative technical improvements belong to the protection scope of the present invention.

It should be noted that like numerals and letters denote similar items in the following figures, therefore, once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "inner" and "outer" are based on the Orientation or positional relationship, or the orientation or positional relationship that the inventive product is usually placed in use, is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, so as to Specific orientation configurations and operations, therefore, are not to be construed as limitations on the invention.

In the description of the present invention, it should also be noted that, unless otherwise clearly specified and limited, the terms "installation", "installation", "connection" and "connection" should be understood in a broad sense, for example, it may be a fixed connection, It can also be a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediary, and it can be the internal communication of two components.

In the description of the present invention, it should also be explained that in this article, relative terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and not necessarily No such actual relationship or order between these entities or operations is required or implied. The terms "horizontal", "vertical", "overhanging" and the like do not imply that the part is absolutely level or overhanging, but may be slightly inclined. For example, "horizontal" only means that its direction is more horizontal than "vertical", and it does not mean that the structure must be completely horizontal, but can be slightly inclined. The term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article or apparatus comprising a set of elements includes not only those elements but also other elements not expressly listed elements, or also elements inherent in such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

Some embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. In the case of no conflict, the following embodiments and features in the embodiments can be combined with each other.

first embodiment

This embodiment provides an LED filament manufacturing process. Please refer to FIG. 1 . FIG. 1 shows a flow chart of the LED filament manufacturing process provided by this embodiment.

Step S10 : Open through holes 112 at the positive and negative terminals of the substrate 110 .

The substrate 110 is the carrier of the LED chip 120 , the metal connection wire 140 , the pin 130 and the sealant. The substrate 110 can be selected from transparent sapphire AL203, boride glass, metal copper sheet, FPC flexible circuit board and other ceramic materials, which are not limited in the present invention. In terms of light extraction efficiency, transparent sapphire boride glass is superior to metal sheets.

The process provided in this embodiment can choose to process sapphire boride glass as the substrate 110 . In other embodiments, different materials can also be selected as the substrate 110 according to actual needs. Through chemical cutting or physical drilling, through holes 112 are respectively opened at the positive connection end and the negative connection end of the substrate 110. For example, physical cutting can be performed at the corresponding position of the substrate 110, such as drill drilling, laser cutting, etc. In order to realize the effect of opening the through hole 112 .

S20: Pass each pin body 132 of the LED filament 100 through a corresponding through hole.

Each pin body 132 of the LED filament 100 is passed through a corresponding through hole 112, and one end of the pin body 132 is used to connect with the solder paste layer 113, thereby connecting with the remaining circuit components of the substrate 110, The other end is used as a port of the LED filament 100 to connect electrical signals. If the pins 130 at both ends of the LED filament 100 are simply bonded to the solder paste layer 113 at both ends of the substrate 110 by low-temperature compression bonding, it is difficult to ensure a firm connection. It is easy to collapse with the solder paste layer 113, forming a false soldering, resulting in subsequent lighting products such as being transported and vibrated, and then the lamps are not lit after being powered on.

A crystal bonding step is also included before step S20. Please refer to Figure 2, the die bonding steps include:

S101 : Using the substrate 110 to fix and package the LED chip 120 .

A primer is coated on the first surface of the substrate 110 to form a primer layer; a plurality of LED chips 120 are arranged on the substrate 110 , for example, at least 3 LED chips 120 . The plurality of LED chips 120 are evenly spaced on the primer layer. The primer can be transparent thermally conductive silicon primer or tin paste. For example, KER-300/TAD-5000, or reflective and thermally conductive silicone primer KER-3200/TAD-5700, etc.

S102: Connect the plurality of LED chips 120 in series or in parallel by using metal connection wires 140 .

The metal connecting wire 140 can be 99.99% metal connecting wire or other metal connecting wire 140 . The series connection can ensure that the current flowing through each LED chip 120 is the same, and if the same LED chip 120 is used, the luminous power and brightness of each LED chip 120 can be guaranteed to be the same; The voltages at the terminals are the same, and the plurality of LED chips 120 do not interfere with each other, even if a certain LED chip 120 fails, it will not affect the luminous effect of the entire LED filament 100 .

S103 : Solder the metal connecting wire 140 and the through hole 112 through solder paste 113 .

The metal connection wires 140 are connected to the through holes 112 at both ends of the substrate 110 through the solder paste 113 , so that the LED chip 120 and the connection pins 130 are connected. Tin wire can also be selected for welding, which is not limited in the present invention. Please refer to FIG. 4 and FIG. 6 , FIG. 4 shows a schematic diagram of the LED filament 100 .

The LED filament manufacturing process also includes a sealing step. The glue sealing step includes S104-S105. See Figure 3.

The substrate 110 of the LED filament 100 must have good rigidity and transparency, so theoretically the LED chips 120 should be placed on both the first and second surfaces of the substrate 110, but in order to follow the principle of simplicity and economy and the consideration of the packaging process , in this embodiment, the LED chip 120 of the LED filament 100 is only disposed on the first surface of the substrate 110 , but it is not limited thereto. In other embodiments of the present invention, the LED chip 120 can also be disposed on the front and back sides of the substrate 110 to achieve the best luminous effect.

S104 : Stir evenly the substrate 110 and the LED chip 120 with silica gel or epoxy resin glue and phosphor powder to form a sealing glue layer 150 .

The LED chip 120 and the substrate 110 are coated with die-bonding glue by a glue dispenser, so that the solder paste layer 113 is exposed for connecting the pins 130 .

Die-bonding glue requires a high thermal conductivity, and requires a thermal conductivity of 0.2W (m·k) or more. The main function of the die-bonding glue is to fix the LED chip 120, and the die-bonding glue can be packaging glue, silica gel or epoxy resin glue.

S105: Coating the configured phosphor on the sealant layer.

Phosphor powder is used to coat the entire colloid to prevent leakage of light emitted by the LED chip 120 . Different luminescent effects can be achieved through different phosphors. Generally, commonly used phosphors include yellow powder, red powder and green powder, etc. The remaining phosphors of different colors can be formed by uniform mixing of different proportions of yellow powder, red powder and green powder. In order to achieve the effect of making the LED filament 100 emit light of different colors. In this embodiment, the fluorescent powder includes at least one of yellow powder, red powder and green powder.

S30: Bending the lead body 132 passing through the through hole 112 , and pressing the bent part of the lead body 132 to form the fixing portion 134 , so that the lead 130 is bonded to the substrate 110 .

The pins 130 are pressed together so that the pins 130 form a fixing portion 134 , so that the pins 130 are in contact with the solder paste layer 113 on the substrate 110 . It can be understood that the maximum width of the fixing portion 134 is greater than the maximum width of the through hole, so that after the pin body 132 passes through the through hole 112, the fixing portion 134 can not pass through the through hole 112, so that the pin body 132 The two ends are respectively located on two sides of the substrate 110 , so that the pins 130 are not easy to be soldered or peeled off by the solder paste on the substrate 110 .

In this embodiment, the fixing part 134 can be arranged in a bent structure by pressing, but it is not limited thereto. In other embodiments, the fixing part 134 can also be arranged in other shapes by pressing, such as a door shape. , so that it can be automatically punched and engaged with the substrate 110 to be firmly connected. The fixing part 134 can also be set in a seven-shaped shape, but it is not limited thereto. The solutions equivalent to this embodiment, or those that can achieve the effect of this embodiment are all within the protection scope of the present invention.

The material of the pin 130 can be selected from a material with good electrical and thermal conductivity, such as nickel-plated copper and the like.

It should be noted that, even if the fixing portion 134 is provided, the pin 130 can still be press-welded with the solder paste layer 113, for example, the pin body 132 can be welded with the solder paste by soldering. The substrate 110 is fixedly connected to achieve the best use effect. Therefore, even if the solder falls off, the fixing portion 134 can still fix the pin 130 .

Through the manufacturing process provided in this embodiment, the LED filament 100 with a stable connection structure can be produced, and the end of the pin 130 is more tightly matched with the through hole 112 of the substrate 110, so that the cooperation between the pin 130 and the substrate 110 is more stable. Especially when the ambient temperature rises and the solder connected between the substrate 110 and the pins 130 dissolves, the snap fit structure of the fixing portion 134 and the substrate 110 can ensure that the pins 130 and the substrate 110 remain connected.

second embodiment

Please refer to FIG. 4 , this embodiment provides an LED filament 100 , and the LED filament 100 provided by this embodiment can improve the service life of the LED filament 100 .

In this embodiment, the LED filament 100 includes a substrate 110, a plurality of LED chips 120, metal connecting wires 140, pins 130 and a sealant layer 150. The LED chips 120 are connected in series, and the pins 130 are fixedly connected to the substrate 110 . The sealant layer 150 wraps the LED chip 120 , the substrate 110 and the metal connection wire 140 .

The LED chip 120 is welded on the substrate 110 in a flip-chip manner, and the electrodes of the LED chip 120 are directly welded to the substrate 110 without welding wires, which reduces the processing steps and improves the processing speed. Moreover, it avoids the luminous efficiency affected by the electrodes occupying the light-emitting area in the front-mounted chip, prolongs the service life of the chip, improves the thermal conductivity of the chip, and reduces the defects such as virtual welding and partial welding caused by the welding wire, thereby improving product quality. Rate.

Referring to FIG. 5 and FIG. 6 , in this embodiment, the substrate 110 is provided with a through hole 112 , and the pin 130 is fixedly connected to the substrate 110 through the through hole 112 .

In this embodiment, two through holes 112 are disposed on the substrate 110 , please refer to FIG. 7 , the two through holes 112 are respectively disposed at two ends of the substrate 110 .

It should be noted that, in this embodiment, the two through holes 112 are arranged at both ends of the substrate 110 respectively, but it is not limited thereto. In other embodiments of the present invention, the two through holes 112 may be located at any of the substrate 110 Positions, solutions equivalent to this embodiment, and those that can achieve the effects of this embodiment are all within the protection scope of the present invention.

In this embodiment, there are two pins 130 , and one pin 130 is fixed to the substrate 110 through one through hole 112 . Both ends of the substrate 110 are coated with a solder paste layer 113 , and each pin 130 is correspondingly connected to the solder paste layer 113 at one end.

Please refer to FIG. 8. In this embodiment, the pin 130 includes a pin body 132 and a fixing portion 134. The pin body 132 passes through the through hole 112 and is fixedly connected to the substrate 110. One side of the pin body 132 passes through the through hole. A portion of the hole 112 is connected to the fixing portion 134 .

Preferably, the outer circumference of the pin body 132 matches the inner wall of the through hole 112 . That is, in this embodiment, the outer periphery of the pin body 132 is in contact with the inside of the through hole 112 .

In this embodiment, the pin body 132 has an interference fit with the through hole 112 . The pin body 132 can be engaged with the through hole 112 to fix the pin body 132 and the through hole 112 .

It should be noted that, in this embodiment, the pin body 132 is interference fit with the through hole 112, but it is not limited thereto. In other embodiments of the present invention, the pin body 132 can be clearance fit with the through hole 112, and The solutions equivalent to this embodiment, which can achieve the effect of this embodiment, are all within the protection scope of the present invention.

In this embodiment, the maximum width of the fixing portion 134 is greater than the maximum width of the through hole 112 . The fixed part 134 can be regular shape, also can be irregular shape, no matter it is a regular shape or an irregular shape, the fixed part 134 may have multiple widths, and the maximum width of the fixed part 134 refers to the width dimension of the fixed part 134 The largest width in .

It is easy to understand that the shape of the through hole 112 may be regular or irregular. No matter whether the shape of the through hole 112 is regular or irregular, the through hole 112 may have multiple widths. The maximum width of the through hole 112 is the largest width dimension among the width dimensions of the through hole 112 .

The maximum width of the fixing portion 134 is larger than the maximum width of the through hole 112 . After the pin body 132 passes through the through hole 112 , the fixing portion 134 cannot pass through the through hole 112 , so that the two ends of the pin body 132 are respectively located on two sides of the substrate 110 . The pin 130 is not easy to fall off from the substrate 110 .

In this embodiment, the fixing portion 134 is a bent structure.

It should be noted that, in this embodiment, the fixing portion 134 is a bent structure, but it is not limited thereto. In other embodiments of the present invention, the fixing portion 134 may be of other structures, such as a spherical shape, which is different from that of this embodiment. Equivalent solutions that can achieve the effects of this embodiment are within the protection scope of the present invention.

In this embodiment, the fixing portion 134 may be in a seven-shaped shape.

It should be noted that, in this embodiment, the fixing portion 134 is in a seven-shaped shape, but it is not limited thereto. In other embodiments of the present invention, the fixing portion 134 can also be in other shapes such as a T shape, which is different from that of this embodiment. Equivalent solutions that can achieve the effects of this embodiment are within the protection scope of the present invention.

In this embodiment, a side of the fixing portion 134 close to the substrate 110 abuts against the substrate 110 , that is, in this embodiment, a side of the fixing portion 134 close to the substrate 110 abuts against the substrate 110 .

It should be noted that, in this embodiment, the side of the fixed portion 134 close to the substrate 110 abuts against the substrate 110 , but it is not limited thereto. In other embodiments of the present invention, the fixed portion 134 may not abut against the substrate 110 , solutions equivalent to this embodiment, and those that can achieve the effects of this embodiment are within the protection scope of the present invention.

In this embodiment, the pin body 132 has a large end and a small end, the large end is connected to the fixing portion 134 , and the width of the pin body 132 gradually decreases from the large end to the small end. The pin body 132 can be gradually locked with the through hole 112 during the passing process.

In this embodiment, the pin body 132 is fixedly connected to the substrate 110 by welding.

Preferably, in this embodiment, the pin body 132 is fixedly connected to the substrate 110 by soldering. That is, soldering is performed at the through hole 112 to fix the lead body 132 and the substrate 110 .

In this embodiment, tin is soldered on both sides of the substrate 110 , that is, both sides are covered. The pin body 132 can be fixed from both sides, which improves the fixing effect of the pin 130 .

It should be noted that, in this embodiment, soldering is performed on both sides of the substrate 110, but it is not limited thereto. In other embodiments of the present invention, soldering can be performed on one side of the substrate 110, that is, soldering on one side. The solutions equivalent to the examples, which can achieve the effect of this embodiment, are all within the protection scope of the present invention.

In this embodiment, the sealant layer 150 is made of silica gel or epoxy resin plus fluorescent powder after being evenly stirred. However, it is not limited thereto. In other embodiments of the present invention, solutions equivalent to this embodiment, which can achieve the effect of this embodiment, are within the protection scope of the present invention.

The working principle of the LED filament 100 provided in this embodiment: In this embodiment, one end of the pin body 132 is connected to the fixed part 134, and the other end passes through the through hole 112. The maximum width of the fixed part 134 is greater than the maximum width of the through hole 112. width, so that the fixing part 134 cannot pass through the through hole 112, even after the LED filament 100 is energized, the solder at the soldering point melts due to the temperature rise of the soldering point, and the pin 130 will not be disconnected from the substrate 110.

third embodiment

This embodiment provides an LED filament lamp, which includes a circuit board, and the LED filament 100 described in the first embodiment or the second embodiment, and the LED filament 100 is electrically connected to the circuit board.

To sum up, the present invention provides an LED filament manufacturing process, LED filament and LED filament lamp, which relate to the field of lighting appliances. The LED filament manufacturing process includes: opening through holes at the positive and negative terminals of the substrate; passing the lead body of the LED filament through the corresponding through hole; bending the pin through the end of the through hole, and bending the pin The ends of the LED filament are pressed together to form a fixed part, so that the pins and the substrate are bonded to form a fixed part by bending the part where the pin passes through the substrate, so that the LED filament pins and the substrate are bonded more closely, and it will not occur due to high temperature and other conditions. In the case of shedding, virtual soldering, etc., the LED filament manufacturing process and LED filament provided by the present invention have a firm connection between the pin and the substrate. Even if the solder melts due to high temperature, the pin will not be separated from the substrate, so that the LED filament can work normally, thereby improving The service life of the LED filament is shortened.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. A kind of LED filament manufacturing process, it is characterized in that, described LED filament manufacturing process comprises: Through holes are respectively opened at the positive and negative terminals of the substrate; Pass each pin body of the LED filament through a corresponding through hole; The lead body passing through the through hole is bent, and the bent body part of the lead is pressed to form a fixing part, so that the lead is bonded to the substrate. 2. The LED filament manufacturing process as claimed in claim 1, characterized in that, before passing each pin body of the LED filament through a corresponding through hole, a crystal bonding step is also included: Using the substrate to fix and package the LED chips: coating a primer on the surface of the substrate to form a primer layer, and setting a plurality of LED chips on the primer layer; Connecting the plurality of LED chips in series or in parallel with metal connection wires; The metal connection wires at both ends of the substrate are welded with tin paste or tin wire. 3. The LED filament manufacturing process according to claim 1, characterized in that, after the metal connection wires at both ends of the substrate are soldered with tin paste or tin wire, a sealing step is also included: Use silica gel or epoxy resin glue and fluorescent powder to mix evenly, and then cover the substrate and LED chip to form a sealing layer; The configured phosphor powder is coated on the sealant layer. 4. The LED filament manufacturing process according to claim 3, wherein the fluorescent powder comprises at least one of yellow powder, red powder or green powder. 5. An LED filament, characterized in that, the LED filament is made by the process according to any one of claims 1-4, the LED filament includes a substrate, pins and through holes, and the pins include A pin body and a fixing part, the fixing part is bonded to the substrate, the part of the pin body passing through the through hole is connected to the fixing part, and the width of the fixing part is larger than the through hole . 6. The LED filament according to claim 5, wherein the LED filament comprises a plurality of LED chips and metal connection wires, the LED chips are arranged on the substrate, and the metal connection wires connect the plurality of LED chips In series or in parallel, the two ends of the metal connecting wire are electrically connected to the pins respectively, and the LED filament also includes a sealing layer, and the sealing layer covers the substrate and the LED chip. 7. The LED filament according to claim 5, characterized in that, the LED filament is also provided with tin paste or tin wire, the tin paste or tin wire is used to connect metal connecting wires, and the tin paste or tin wire It is also used for soldering substrate and lead body. 8. The LED filament according to claim 5, wherein the fixing part is a bent structure. 9. The LED filament according to claim 8, wherein the fixing part is a heptagonal structure. 10. The LED filament according to claim 5, wherein the lead body is welded to the substrate.