KR20220036122A - Multi-laser reflow apparatus and method, surface mount system using multi-laser - Google Patents

Abstract

The present invention relates to a multi-laser reflow device and method, and a surface mounting system using a multi-laser, which includes one or more stages on which an object coated with solder paste is placed, and one or more stages that move each stage in a preset processing direction. guide rail; a laser driver that is provided with as many laser modules as the number of guide rails and irradiates a laser beam toward the object located in a heating zone provided for each guide rail; a driving unit that individually drives each of the guide rails; And the laser driver controls the driver to recognize the stage on which the object is mounted to drive a guide rail including the stage, and causes the laser module to irradiate a laser beam in the heating zone in conjunction with the movement of the guide rail. It may be a device including a control unit that controls.

Description

Multi-laser reflow apparatus and method, Surface mount system using multi-laser}

The present invention relates to a reflow technology that allows components to be soldered to an object through heating and melting cooling of solder paste applied on an object on which the component is mounted.

The content described in this part simply provides background information on an embodiment of the present invention and does not constitute prior art.

Surface mounting technology is widely used today because it has several advantages, including denser spacing of electronic components, use of both sides of the board, and reduction of the area of the printed circuit board. Currently common soldering technologies for surface-mounted components include reflow soldering using heat conduction or infrared rays.

Reflow soldering is the process of supplying solder to the lands of a printed circuit board in advance and re-melting the solder with an external heat source to join the leads of surface-mounted components and the circuit pattern on the printed circuit board.

The reflow oven method, which can be mass-produced, has a conveyor transfer part, oven, and exhaust part integrated into the chamber. Therefore, when the PCB is input into the chamber with solder paste applied, the input PCB is transferred into the oven through the conveyor transfer unit. The oven has a preheating section, a main heating section, and a cooling section arranged in that order. Therefore, as the PCB passes through the preheating section and the main heating section, the solder paste is melted by heat and soldering is performed. Then, as the PCB passes through the cooling section, the solder paste is cooled and solidified by cold air, completing the soldering process of the PCB.

However, the reflow oven method has the problem of generating carbonized gas, or flux gas, in the process of melting the solder paste at a high temperature of 210°C to 250°C.

In addition, in the reflow oven method, the reflow profile, which is the relationship between the temperature and time of the solder joint as the substrate passes through the oven, is an important process element, and a preset number of heating zones and cooling zones are used. This provides heating control and cooling control functions. However, because the level of cooling control in the existing reflow oven method is not as good as the heating zone in the preheating and main heating zones, most ovens have a relatively small number of independent cooling zones and are unable to provide rapid cooling.

In the existing reflow oven method, if the temperature rise of 2 to 3 degrees Celsius per second is not maintained in the preheating section, the potential risk of thermal shock or cracking of parts increases, and the solder paste also has a problem of breaking and splashing. In addition, if the temperature in the main heating area is too low or high, there is a problem that not only the component connections, pads, and solder paste are oxidized, but also the solder balls or solder may splash, and if the temperature is too low, there is a problem that the flux may not be fully activated.

Likewise, the existing reflow oven method causes various problems such as hollowness or holes in solder joints, solder bridging, heating imbalance, and damage to boards or components due to temperature uniformity when the reflow profile is not set and managed properly. This can happen.

In order to solve the above-described problem, the present invention sets a heating zone for each plurality of guide rails according to an embodiment of the present invention, and provides a plurality of laser modules to sequentially radiate a laser beam to each heating zone, thereby providing a plurality of The purpose is to increase the production of surface mount components by utilizing guide rails and laser modules.

However, the technical challenge that this embodiment aims to achieve is not limited to the technical challenges described above, and other technical challenges may exist.

As a technical means for achieving the above-described technical problem, a multi-laser reflow device according to an embodiment of the present invention includes one or more stages on which an object to which solder paste is applied is placed, and each stage is moved in a preset processing direction. one or more guide rails for moving; a laser driver that is provided with as many laser modules as the number of guide rails and irradiates a laser beam toward the object located in a heating zone provided for each guide rail; a driving unit that individually drives each of the guide rails; And the laser driver controls the driver to recognize the stage on which the object is mounted to drive a guide rail including the stage, and causes the laser module to irradiate a laser beam in the heating zone in conjunction with the movement of the guide rail. It is characterized by comprising a control unit that controls.

At this time, the laser driving unit includes a body portion having a polygonal cross-section including a plurality of planes; a laser module mounted on at least one side of the body; a driving frame rotatably supporting a rotation axis formed at the center of the body portion; and a driving driver that sequentially drives the laser module by rotating the rotation axis in a preset direction.

The laser module includes a cooling device for cooling, and the body portion is formed with a receiving portion that accommodates the cooling tube of the cooling device, and the cooling tube is exposed to the outside through the receiving portion.

The laser driving unit is located vertically above the guide rail, and each laser module of the laser driving unit is positioned in one-to-one correspondence with each guide rail.

Meanwhile, a surface mounting system using a multi-laser according to another embodiment of the present invention includes a loader unit for loading an object to which solder paste is applied into a reflow soldering area; A mounter unit that mounts the component on the object to which the solder paste is applied; When the object is located in the reflow soldering area and the component is mounted on the stage, the stage is moved in a preset processing direction and a laser beam corresponding to each heating zone is directed toward the object from at least one heating zone. A multi-laser reflow device that irradiates and performs a reflow soldering process; and an unloader unit that unloads the soldered object to the outside through the multi-laser reflow device, wherein the loader unit, mounter unit, multi-laser reflow device, and unloader unit are in-line. It is characterized by being placed.

In the multi-laser reflow device, a cooling zone is set at a preset distance from the heating zone, and the solder paste heated and melted in the heating zone is cooled in the cooling zone to solder the component to the object. It is characterized by further including wealth.

The multi-laser reflow method performed by a reflow device for soldering an object using a laser according to an embodiment of the present invention involves moving one or more stages on which an object coated with solder paste is placed in a preset processing direction. A moving process of placing it in at least one heating zone; A heating process of heating the object by irradiating a laser beam at a preset time difference from each heating zone to the object; When the solder paste is melted through the heating process, a cooling process of moving the object to a cooling zone to cool the molten solder paste; And it may be a multi-laser reflow method including an unloading process of unloading the soldered object to the outside through the cooling process.

According to the means for solving the problem of the present invention described above, the present invention sets a heating zone for each of a plurality of guide rails and drives the laser module so that the laser beam is irradiated sequentially to each heating zone, so that the guide rail and the corresponding guide rail are produced according to the production volume. The operation of the laser module can be controlled, which allows simultaneous production of a variety of products by loading different surface-mounted components on each guide rail, and the production of the same surface-mounted components can be increased by utilizing all guide rails. .

1 is a diagram explaining the configuration of a multi-laser reflow device according to an embodiment of the present invention.
FIG. 2 is an exemplary diagram explaining a guide rail, which is a component of FIG. 1.
Figure 3 is a diagram explaining the configuration of a laser driving unit according to an embodiment of the present invention.
Figure 4 is an exemplary diagram explaining the configuration of a laser module according to an embodiment of the present invention.
Figure 5 is a diagram illustrating a reflow process of a multi-laser reflow device according to an embodiment of the present invention.
Figure 6 is a diagram explaining the configuration of a surface mounting system using a multi-laser according to an embodiment of the present invention.
Figure 7 is a flowchart explaining a multi-laser reflow method according to an embodiment of the present invention.

Below, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. In order to clearly explain the present invention in the drawings, parts unrelated to the description are omitted, and similar parts are given similar reference numerals throughout the specification.

Throughout the specification, when a part is said to be "connected" to another part, this includes not only the case where it is "directly connected," but also the case where it is "electrically connected" with another element in between. . In addition, when a part is said to "include" a certain component, this does not mean excluding other components unless specifically stated to the contrary, but may further include other components, and means that it may further include one or more other components. It should be understood that this does not exclude in advance the possibility of the presence or addition of features, numbers, steps, operations, components, parts, or combinations thereof.

The following examples are detailed descriptions to aid understanding of the present invention and do not limit the scope of the present invention. Accordingly, inventions of the same scope and performing the same function as the present invention will also fall within the scope of rights of the present invention.

Additionally, each configuration, process, process, or method included in each embodiment of the present invention may be shared within the scope of not being technically contradictory to each other.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the attached drawings.

FIG. 1 is a diagram explaining the configuration of a multi-laser reflow device according to an embodiment of the present invention, and FIG. 2 is an exemplary diagram explaining a guide rail, which is a component of FIG. 1.

The multi-laser reflow device 100 moves the object on which the component is mounted (for example, a printed circuit board, etc.) in the processing direction while heating it in a heating zone to melt the solder paste applied on the object, and then melts the molten solder. The paste is cooled and solidified in a cooling zone so that the component can be soldered onto the object.

This multi-laser reflow device 100 includes, but is not limited to, a plurality of guide rails 120, a laser driving unit 130, a driving unit 150, and a control unit 160.

The plurality of guide rails 120 include one or more stages 110 on which the object 101 to which solder paste is applied is placed, and each stage 110 is moved in a preset processing direction. These guide rails 120 may be provided in various numbers, such as 1, 4, or 8. As shown in FIG. 2, first to fourth guide rails 121, 122, 123, and 124 are provided. In this case, first to fourth stages 111, 112, 113, and 114 are disposed on each guide rail 121, 122, 123, and 124. Each guide rail (121, 122, 123, 124) may be arranged at a certain distance apart or may be arranged in contact with each other without any separation distance.

The laser driver 130 is provided with as many laser modules 140 as the number of guide rails 120, and when the object 101 is located in the heating zone provided for each guide rail 120, the laser driver 130 is directed toward the object 101. Examine the beam.

The driving unit 150 individually drives each guide rail 120.

When the stage 110 on which the object 101 is mounted is recognized, the control unit 160 controls the driving unit 150 to drive the guide rail 120 including the stage 110, and moves the guide rail 120. In conjunction with this, the laser driver 130 is controlled so that the laser module 140 radiates a laser beam in the heating zone. When the object 101 is placed on the first stage 111 and the object 101 is placed on the second stage 112 with a certain time difference (Δt), the control unit 160 operates the first stage 111 through the driving unit 150. ) is driven, and the second guide rail 122 including the second stage 112 is driven at regular time difference (Δt) intervals. In addition, the control unit 160 operates the laser module 142 corresponding to the second guide rail 122 at a certain time difference (Δt) after the laser module 141 corresponding to the first guide rail 121 is driven. Let it run.

Therefore, the control unit 160 uses the time difference (Δt) to allow the loading process, mounting process, reflow soldering process, and unloading process to proceed simultaneously in each guide rail 120, thereby reducing the thermal stress that components receive during soldering using a laser. It reduces the waiting time for each process, speeding up reflow soldering and surface mounting operations, and increases productivity by performing all processes independently and separately for each guide rail instead of having to perform them sequentially on one rail. This makes mass production possible.

Figure 3 is a diagram explaining the configuration of a laser driving unit according to an embodiment of the present invention.

Referring to FIG. 3, the laser driving unit 130 includes a body unit 131 having a polygonal cross-section including a plurality of planes, a laser module 140 mounted on at least one surface of the body unit 131, A driving frame (not shown) that rotatably supports the rotation axis 132 formed at the center of the body 131 and a driving driver that sequentially drives the laser module 140 by rotating the rotation axis 132 in a preset direction ( (not shown).

The body portion 131 may be formed in various polygonal shapes such as triangles, squares, and hexagons, and the laser module 140 is not installed on each side of the body portion 131 on the same line, but at certain positions on different lines. is installed in That is, the first laser module 141 installed on the first side of the body 131 and the second laser module 142 installed on the third side are installed at a distance of d1, where the distance d1 is the guide rail 120. It is set considering the time difference (Δt) of these sequential drives.

When the body portion 131 has a hexagonal cross-section, laser modules 141, 142, and 143 are installed on the first, third, and fifth sides, respectively, taking into account the separation distance between the guide rails 120. Laser modules are not installed on the 2nd, 4th, and 6th sides. When the cross-section of the body 131 is square, all four laser modules can be installed on each side, but considering the separation distance between the guide rails 120, an optical system is installed on the laser module 140 to control the laser beam. By adjusting the angle, the laser beam can be irradiated only to the top of the object of each guide rail 120.

If the guide rails 120 are arranged in contact with each other without a separation distance, the laser module 140, located in one-to-one correspondence with each guide rail 120, sequentially emits a laser beam for each guide rail at a certain time interval. irradiate, and ensure that the laser beam is irradiated only to the heating zone that applies to you.

This laser driving unit 130 is located vertically above the guide rail 120 and driven in the form of a roller rotating in a certain direction, and the laser module 140 installed on each side of the laser driving unit 130 is connected to each guide rail 120. ) and is positioned to correspond one-to-one. This laser module 140 irradiates a laser beam in the form of a surface light source corresponding to the size of the object 101, that is, the printed circuit board, thereby minimizing laser loss and maximizing productivity.

In the existing method of laser bonding while pressing the substrate, the pressurizing head and the laser irradiation unit (laser module) are formed as one piece, so gas (flux) is generated in the process of melting and cooling the solder paste, and this gas is transmitted to the pressurized object. If it sticks to the bottom of the machine and is irradiated with a laser, it can act as a causative agent for combustion. In addition, if the pressure head is damaged, the laser irradiation unit cannot be used, so to replace the damaged pressure head, the entire pressure head and laser irradiation unit must be disassembled, which has the disadvantage of requiring a lot of replacement time.

However, since the laser driving unit 130 is not a pressurizing type in which the existing pressurizing head and the laser irradiation unit are formed in an integrated form, the tact time for the object is shortened, and it is possible to speed up the soldering work for the entire object. .

Figure 4 is an exemplary diagram explaining the configuration of a laser module according to an embodiment of the present invention.

As shown in FIG. 4, the laser module 140 includes a plurality of diode lasers arranged radially, an optical system that condenses each laser beam output from each laser diode, and an optical fiber that transmits each laser beam to the optical system. and a cooling device 400 for cooling. Accordingly, the body portion 131 of the laser driver 130 is formed with a receiving portion (not shown) that accommodates the cooling tubes 410 and 420 of the cooling device 400, and an inlet tube 410 through which the coolant enters the receiving portion. ) and the cooling tubes 410 and 420, including the outlet tube 420 through which the coolant is discharged, are exposed to the outside.

At this time, the cooling device 400 is built into the main body of the laser module 140, and the laser module 140 can arrange a plurality of laser output diode lasers in a line. The cooling device 400 may be composed of a circulation system that circulates the coolant so that the diode laser contacted by the coolant circulated internally can be cooled, and the coolant flows inside the main body of the laser module 140 to operate the laser module ( 140) is vaporized by taking away the heat, for example water can be used.

Since the laser module 140 configured in this way drives a plurality of high-output diode lasers, a lot of heat can be generated and the optical output power can be reduced. Therefore, the high-output diode laser is cooled by cooling the laser module 140 through a cooling device. Even when driven, the center wavelength is stable and the optical output can be stably maintained at up to 500W at highest efficiency.

Figure 5 is a diagram illustrating a reflow process of a multi-laser reflow device according to an embodiment of the present invention.

Referring to FIG. 5, when an object 101 coated with solder paste is placed on the upper surface of the stage 110 and an electronic component is mounted on the object 101 coated with solder paste, the guide rail 120 moves in the processing direction. It moves at a preset speed.

When the object is located in the heating zone, the laser driver 130 drives the laser module 140 corresponding to the currently moving guide rail 120 to radiate a laser beam to the upper part of the object 101.

Meanwhile, in the multi-laser reflow device 100, a cooling zone is set at a preset distance from the heating zone, and the solder paste heated and melted in the heating zone is cooled in the cooling zone to solder the electronic components to the object 101. It further includes a cooling unit (not shown) that makes it possible.

Accordingly, the guide rail 120 is moved from the heating zone to the cooling zone after a certain period of time, and the solder paste heated and melted by the cooling unit is cooled and solidified to complete soldering of the electronic component to the object 101.

Figure 6 is a diagram explaining the configuration of a surface mounting system using a multi-laser according to an embodiment of the present invention.

Referring to FIG. 6, the surface mounting system 600 using a multi-laser includes a loader unit 610, a mounter unit 620, a multi-laser reflow device 630, and an unloader unit 640, and the loader unit 610, mounter unit 620, multi-laser reflow device 630, and unloader unit 640 are arranged in-line.

The loader unit 610 loads the object coated with solder paste into the reflow soldering area, and the mounter unit 620 mounts the component on the object coated with solder paste.

The unloader unit 640 unloads the soldered object to the outside through the multi-laser reflow device 630. Here, the multi-laser reflow device 630 is configured in the same way as the multi-laser reflow device 100 described in FIGS. 1 to 5.

The surface mounting system 600 using such a multi-laser can use a plurality of guide rails 120 depending on the production volume, and each guide rail 120 is maintained at a certain time difference (Δt) during the loading process of the loader unit 610. , the mounting process of the mounter unit 620, the reflow process of the multi-laser reflow device 6300, and the unloading process of the unloader unit 640 can be performed sequentially. At this time, the surface mounting system 600 using a multi-laser is used to determine the size of the object, the number of electronic components mounted on the object, the moving speed of the guide rail, the time required for heating, melting, and cooling of the multi-laser reflow device 100, etc. Taking this into account, a time difference (Δt) for sequentially driving each guide rail 120 can be set.

Figure 7 is a flowchart explaining a multi-laser reflow method according to an embodiment of the present invention.

Referring to FIG. 7, in the multi-laser reflow method performed by the above-described multi-laser reflow device, when the object to which solder paste is applied is placed on the stage 110 in the moving process (S1), the guide rail 120 The object is moved in the preset processing direction and placed in the heating zone corresponding to the guide rail 120.

The heating process (S2) heats the solder paste by irradiating laser beams from each heating zone toward the object at a preset time difference. At this time, the laser driver 130 is located vertically above the heating zone set for each guide rail 120, and the laser module 140 installed on the laser driver 130 radiates a laser beam toward the object at a certain time difference. Therefore, the heating and melting operations for the solder paste applied to the object are not performed simultaneously in a plurality of heating zones, and as a result, the reflow process can be performed independently without being affected by the laser beam in the adjacent heating zones. there is.

In the cooling process (S3), when the solder paste is melted through the heating process (S2), the object is moved to the cooling zone to cool the molten solder paste, and in the unloading process (S4), soldering is performed through the cooling process (S3). Unload the completed object to the outside.

Meanwhile, steps S1 to S4 of FIG. 7 may be divided into additional steps or combined into fewer steps depending on the implementation of the present invention. Additionally, some steps may be omitted or the order between steps may be changed as needed.

The description of the present invention described above is for illustrative purposes, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical idea or essential features of the present invention. will be. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive. For example, each component described as single may be implemented in a distributed manner, and similarly, components described as distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention. do.

100: Multi-laser reflow device
110: stage
120: Guide rail
130: Laser driving unit
131: body part
132: rotation axis
140: Laser module
150: driving unit
160: control unit
400: Cooling device
600: Surface mounting system using multi-laser
610: loader unit
620: Mounter unit
630: Multi-laser reflow device
640: Unloader unit

Claims (10)

It includes one or more stages on which an object to which solder paste is applied is placed, and one or more guide rails that move each stage in a preset processing direction;
a laser driver that is provided with as many laser modules as the number of guide rails and irradiates a laser beam toward the object located in a heating zone provided for each guide rail;
a driving unit that individually drives each of the guide rails; and
The driving unit is controlled to recognize the stage on which the object is seated so that the guide rail including the corresponding stage is driven, and the laser driving unit is linked to the movement of the guide rail so that the laser module radiates a laser beam in the heating zone. A multi-laser reflow device comprising a control unit for controlling. According to paragraph 1,
The laser driving unit,
A body portion having a polygonal cross-section including a plurality of planes;
a laser module mounted on at least one side of the body;
a driving frame rotatably supporting a rotation axis formed at the center of the body portion; and
A multi-laser reflow device comprising a driving driver that sequentially drives the laser module by rotating the rotation axis in a preset direction. According to paragraph 2,
The laser module includes a cooling device for cooling,
A multi-laser reflow device, wherein the body portion is formed with a receiving portion that accommodates the cooling tube of the cooling device, and the cooling tube is exposed to the outside through the receiving portion. According to paragraph 1,
The laser driving unit is located vertically above the guide rail,
A multi-laser reflow device, characterized in that each laser module of the laser driving unit is positioned in one-to-one correspondence with each guide rail. A loader unit that loads an object coated with solder paste into the reflow soldering area;
A mounter unit that mounts the component on the object to which the solder paste is applied;
When the object is located in the reflow soldering area and the component is mounted on the stage, the stage is moved in a preset processing direction and a laser beam corresponding to each heating zone is directed toward the object from at least one heating zone. A multi-laser reflow device that irradiates and performs a reflow soldering process; and
It includes an unloader unit that unloads the soldered object to the outside through the multi-laser reflow device,
A surface mounting system using a multi-laser, wherein the loader unit, mounter unit, multi-laser reflow device, and unloader unit are arranged in-line. According to clause 5,
The multi-laser reflow device,
One or more guide rails including one or more stages on which the object on which the part is mounted is placed, and moving each stage in a preset processing direction;
a laser driver that is provided with as many laser modules as the number of guide rails and irradiates a laser beam toward the object in a heating zone;
a driving unit that individually drives each of the guide rails; and
The driving unit is controlled to drive a guide rail that recognizes the stage on which the object is mounted and moves the stage, and the laser driving unit is linked to the movement of the guide rail so that the laser module radiates a laser beam in the heating zone. A surface mounting system using a multi-laser, characterized in that it includes a control unit for controlling. According to clause 6,
The laser driving unit,
A body portion having a polygonal cross-section including a plurality of planes;
a laser module mounted on at least one side of the body;
a driving frame rotatably supporting a rotation axis formed at the center of the body portion; and
A surface mounting system using a multi-laser, comprising a driving driver that sequentially drives the laser module by rotating the rotation axis in a preset direction. According to clause 5,
The multi-laser reflow device,
A cooling zone is set at a preset distance from the heating zone, and the cooling zone further includes a cooling unit that cools the solder paste heated and melted in the heating zone to solder the component to the object. Surface mounting system using multi-laser. According to clause 6,
The laser driving unit is located vertically above the guide rail,
A surface mounting system using a multi-laser, characterized in that each laser module of the laser driver is positioned in one-to-one correspondence with each guide rail. In the multi-laser reflow method performed by a reflow device for soldering an object using a laser,
A moving process of moving one or more stages on which an object coated with solder paste is placed in a preset processing direction and placing them in at least one heating zone;
A heating process of heating the object by radiating a laser beam from each heating zone toward the object at a preset time interval;
When the solder paste is melted through the heating process, a cooling process of moving the object to a cooling zone to cool the molten solder paste; and
A multi-laser reflow method comprising an unloading process of unloading the soldered object to the outside through the cooling process.

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