Heating device, soldering method and welding method using the same

Abstract

To provide a heating device and a heating method which can flexibly deal with changes in soldering and welding targets and are used for energy-saving and inexpensive soldering and welding.SOLUTION: A heating device 1 used for soldering or welding includes: one or more spot lamp heaters 10 including a heating lamp 11 and a condensing optical system 12; and a multi-articulated robot 30 which controls a position and a direction of the spot lamp heater 10. The emission light of the heating lamp 11 of the spot lamp heater 10 is concentrated to a prescribed spot size with the condensing optical system 12, the concentrated light is radiated to a target 80 and the target is heated.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a heating device and a heating method used in soldering, welding, semiconductor processes, and the like. [Background technology]

[0002] Conventionally, soldering methods for mounting electronic components on a circuit board have been the flow method, in which molten solder is sprayed onto the solder surface of the board, and the reflow method, in which cream solder that has been applied in advance to the "land" part to be soldered is melted in a reflow furnace to join the parts. In recent years, from the viewpoint of energy conservation, a method has been introduced in which, in combination with a robot, only the parts to be soldered are heated, rather than the entire board. For example, a method of heating with a soldering iron (Patent Document 1) and a method of reflowing only the parts to be soldered by laser heating (Patent Document 2) are known. These methods, in combination with a robot, can flexibly accommodate changes in the soldering target, and can be used for multi-product production.

[0003] On the other hand, welding methods that have been used include arc welding (Patent Document 3), which generates an arc between the base material and a welding rod or electrode to weld, gas welding using the heat of a gas flame, and spot welding (Patent Document 4), which clamps the base material between two electrodes and applies current to locally heat and pressure to weld it. However, from the perspective of energy conservation and power saving, laser welding (Patent Document 5), which welds using heat from laser irradiation, has also been introduced, and automation is being attempted in combination with robots. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 8-18215 [Patent Document 2] Japanese Patent Application Publication No. 2-92452 [Patent Document 3] Patent Publication No. 2021-094581 [Patent Document 4] JP 2022-100858 A [Patent Document 5] JP 2018-183799 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the method of combining a robot with localized laser irradiation for soldering or welding has the advantage of being flexible and able to handle small-lot, high-mix production, but has the problem that the laser light source and other components are expensive.

[0006] The present invention aims to solve the above problems, and to provide a heating device and a heating method for use in energy-saving and inexpensive soldering and welding, which can flexibly accommodate changes in the objects to be soldered or welded. [Means for solving the problem]

[0007] In order to solve the above problems, the heating device of the present invention is a heating device used for soldering or welding, one or more spot lamp heaters including a heating lamp and focusing optics; an articulated robot for controlling the position and direction of the spot lamp heater; Including, The light emitted from the heating lamp of the spot lamp heater is focused to a predetermined spot size by the focusing optical system and irradiated onto an object to heat it.

[0008] The heating lamp is preferably a halogen lamp or a xenon lamp.

[0009] The heating device may have a plurality of spot lamp heaters having different spot sizes at the focus of the light collecting optical system, so that different spot lamp heaters can be used depending on the location to be heated.

[0010] A shutter for opening and closing the optical path of the light emitted from the spot lamp heater may be further provided, and the exposure time of the heated portion may be controlled by opening and closing the shutter.

[0011] The apparatus may further include a fixing table for fixing the object, the fixing table being provided with a preheater for preheating the object.

[0012] The apparatus may further include a chamber that seals the object fixed to the fixing table and has a transparent window, an exhaust pipe for exhausting the inside of the chamber, and a purge pipe for introducing a purge gas into the inside of the chamber, wherein light emitted from the spot lamp heater is irradiated onto the object through the transparent window of the chamber, and the inside of the chamber may be configured to be able to be exhausted.

[0013] The soldering method of the present invention is a method in which solder is applied in advance to the land portion of the electronic board, electronic components are placed on the land portion, and the solder is then heated using the above-mentioned heating device to reflow and perform soldering.

[0014] The welding method of the present invention is a method for heating and welding the butted joint between workpieces to be welded together using the above-mentioned heating device. Effect of the Invention

[0015] According to the present invention, by adopting a spot lamp heater including an inexpensive heating lamp, it is possible to realize high temperatures at which spot soldering and welding can be performed. Therefore, by combining it with an articulated robot, it is possible to flexibly respond to changes in the objects to be soldered or welded, and an energy-saving and inexpensive heating device can be provided. [Brief description of the drawings]

[0016] [Figure 1] 1 is a conceptual diagram showing a heating device according to an embodiment of the present invention. [Diagram 2] 2 is a conceptual diagram showing a spot lamp heater of the heating device in FIG. 1. [Diagram 3]2 is a conceptual diagram showing a shutter part of the heating device in FIG. 1. [Figure 4A] FIG. 2 is a conceptual diagram showing an initial state of the heating device in FIG. [Figure 4B] 2 is a conceptual diagram showing a state in which the heating device in FIG. 1 has received an object. FIG. [Figure 4C] 2 is a conceptual diagram showing a state in which the heating device in FIG. 1 fixes an object. FIG. [Figure 4D] 2 is a conceptual diagram showing a state in which the heating device of FIG. 1 seals an object. FIG. [Figure 4E] 2 is a conceptual diagram showing a state in which the heating device in FIG. 1 irradiates an object with emitted light. [Figure 4F] 2 is a conceptual diagram showing a state in which the heating device in FIG. 1 irradiates an object with emitted light. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, a heating device 1 according to an embodiment of the present invention will be described with reference to Fig. 1 to Fig. 4F. As shown in Fig. 1, the heating device 1 includes two spot lamp heaters 10, a shutter 20, an articulated robot 30, a fixed base 40, a chamber 50, an exhaust pipe 60, a purge pipe 65, and a control unit 70.

[0018] As shown enlarged in FIG. 2, the spot lamp heater 10 is a light source unit that includes a halogen lamp (heating lamp) 11 and a focusing mirror (focusing optical system) 12, and focuses the light emitted from the halogen lamp 11 to a predetermined spot size by the focusing mirror 12 and irradiates the target object 80 (see FIG. 1). The halogen lamp 11 is a lamp in which a small amount of halogen gas is introduced in addition to an inert gas inside the bulb to achieve high output and long life. Commercially available lamps of, for example, 150 W to 2 kW can be used.

[0019] The light collecting mirror (light collecting optical system) 12 is a mirror with a substantially elliptical spherical shape, and is formed, for example, by mirror-finishing metal or coating glass with metal, and collects the light emitted from the halogen lamp 11. When the filament of the halogen lamp 11 is placed at one focus f0 of the elliptical spherical surface E, the light is collected at the other focus f1 of the elliptical spherical surface E. A maximum temperature of about 1500°C can be obtained near this focus f1, making soldering and welding possible. The spot size is, for example, about Φ5 mm near the focus f1, and this "spot size at the focus" is considered to be determined by the size of the lamp filament. The spot size increases as it moves away from the focus f1 in the optical axis direction, so the spot size on the object 80 can be adjusted by adjusting the position of the spot lamp heater 10 in the optical axis direction. However, there is an advantage in that the spot size is stabilized by adjusting the position of the spot lamp heater 10 so that the object 80 is near the focus f1.

[0020] The heating device 1 of this embodiment has two spot lamp heaters 10a, 10b with different spot sizes at the focus f1 of the collecting mirror (collecting optical system) 12, so that different spot lamp heaters 10a, 10b can be used depending on the heating location. With this configuration, a spot lamp heater with an appropriate spot size can be selected and used, so that it can be flexibly adapted to cases where the size of the heating spot varies depending on the object to be soldered or welded and the heating spot. In this embodiment, the collecting optical system is the collecting mirror 12, but a collecting lens may be used, or a collecting mirror and a collecting lens may be combined. The spot lamp heater 10 including the halogen lamp 11 and the condenser mirror 12 may be a commercially available product.

[0021] 3, the shutter 20 is attached to the emission side of each spot lamp heater 10 to open and close the optical path of the emitted light, and the exposure time to the heated area can be controlled by turning on and off this shutter 20. In this embodiment, an air-driven rotary actuator 21 moves the rotational position of shutter blades 22 to close and open the optical path of the emitted light. This configuration enables faster control than turning on and off the halogen lamps (heating lamps) 11 of the spot lamp heaters 10, and ensures that only the required area is heated.

[0022] The articulated robot 30 is a robot that controls the position and direction of the spot lamp heater 10 . 1, the articulated robot 30 in this embodiment has a base 31, a robot arm 32 having three bending joints J1 to J3 and three torsion axes T1 to T3, and is a robot that can be controlled along six axes and is capable of performing various operations. Two spot lamp heaters 10a, 10b and their respective shutters 20 are attached to a tip 32a of the robot arm 32. This articulated robot 30 may be a commercially available one, and can be taught its movements using dedicated control software, and can repeatedly execute the movements that have been taught. With this configuration, the articulated robot 30 can perform a variety of movements through teaching, etc., and can therefore flexibly accommodate changes in the soldering and welding objects. However, this articulated robot 30 does not necessarily have to have six axes, and may have any number of axes equal to or greater than two.

[0023] The fixing table 40 is a jig for placing the object 80, and includes, for example, a base 41, a clamping mechanism 42 for clamping the object 80, and a lift pin 43 for lifting the object 80 to facilitate the loading and unloading of the object 80, as shown in FIG. 1, so that the object 80 to be soldered or welded can be fixed on the base. However, as a fixing means, vacuum suction or magnetic suction may be used instead of the mechanical clamping mechanism 42 shown in the figure. Also, depending on the structure of the transport mechanism for the object 80 and the transport method (e.g., manual), the lift pin 43 is not necessarily provided. Also, if the bottom surface of the object 80 (the surface that contacts the base 41) is uneven, heating the object 80 directly will cause uneven heating, so the lift pin 43 may be protruded from the base 41 to an extent (0.1 to 3.0 mm) that prevents the unevenness of the bottom surface of the object 80 from touching the base 41, so that the object 80 can be heated in a floating manner in accordance with a proximity heating method. At this time, the clamp mechanism 42 is not used. In this embodiment, a preheater 44 for preheating the object 80 is provided inside the base 41 of the fixing table 40. The temperature of the fixing table 40 is monitored by a temperature sensor (not shown), and the output of the preheater 44 is adjusted so that this temperature becomes a set temperature. With this configuration, the object 80 can be preheated, so that soldering or welding can be performed quickly even with the small irradiation energy of the spot lamp heater 10.

[0024] In this embodiment, in order to seal the object 80 in cooperation with the chamber 50 described later, the fixed base 40 is attached to a lifting mechanism 45 consisting of a motor and a feed screw, and is capable of moving between an elevated position in close contact with the chamber 50 and a lowered position away from the chamber 50 to enable the object 80 to be loaded and unloaded manually or by an external transfer robot (not shown). However, this configuration is not limited to this, and a structure in which the fixed base 40 is fixed and the chamber 50 is raised and lowered may also be used, or the fixed base 40 and the chamber 50 may be fixed, and a door for loading and unloading may be provided in the chamber 50, and the object 80 may be loaded and unloaded through this door.

[0025] The chamber 50 is a container that seals the object 80 placed on the fixed stage 40, and is intended to insulate the object 80 from the surrounding atmosphere during heating. As shown in Fig. 1, the chamber 50 has a transparent window 51 made of quartz, and light emitted from the spot lamp heater 10 can be transmitted through this transparent window 51 to irradiate the object 80.

[0026] The chamber 50 is provided with an exhaust pipe 60 connected to an external exhaust pump (not shown) for exhausting the inside of the chamber 50, and a purge pipe 65 connected to an external purge gas source (not shown) for introducing a purge gas into the chamber 50. This "purge gas" is air or N 2 The exhaust pipe 60 and the purge pipe 65 are provided with opening and closing valves 61, 66, respectively, so that, for example, the purge gas is exhausted while being purged during heating of the object 80, thereby removing outgassing during soldering or welding. With this configuration, soldering or welding can be performed in a vacuum or in an inert gas atmosphere, and the outgassing that occurs can be exhausted, thereby improving the quality of the soldering or welding.

[0027] The control unit 70 has a processor (not shown) and driver circuits (not shown) for each unit, and is configured to perform ON / OFF control of the two spot lamp heaters 10a, 10b, opening and closing control of each shutter 20, drive control of the articulated robot 30, drive control of the clamp mechanism 42, lift pin 43 and lifting mechanism 45 of the fixed base 40, and opening and closing control of each opening and closing valve 61, 66 of the exhaust piping 60 and the purge piping 65, as well as communicate with an external transport robot (not shown) to load and unload the target object 80.

[0028] Next, an example of the operation of the heating device 1 of the present invention thus configured will be described with reference to Figures 4A to 4F. In this example, the heating device 1 is configured as a reflow soldering device, and is configured to solder a plurality of soldering points including a first soldering point P1 requiring a first heating energy and a second soldering point P2 requiring a second heating energy.

[0029] 4A, in the initial state, the fixed table 40 is in a lowered position spaced downward from the chamber 50, the lift pins 43 of the fixed table 40 are in an elevated position, the clamp mechanism 42 is in a released state, and no target object 80 is placed on the fixed table 40. However, in order to stabilize the temperature of the fixed table 40, the preheater 44 is continuously turned on in advance. The control unit 70 communicates with an external transfer robot (not shown), and the transfer robot carries in the object 80 and places it on the lift pins 43 as shown in Fig. 4B. This object 80 is a circuit board 81 to be soldered, on which electronic components 82a and 82b are placed. Cream solder has been applied to each land (not shown) of the circuit board 81 in advance.

[0030] When the control unit 70 confirms through a sensor (not shown) that the object 80 has been placed on the lift pins 43, it lowers the lift pins 43 and activates the clamp mechanism 42 to clamp the object 80, as shown in FIG. 4C. Next, the control unit 70 drives the lifting mechanism 45 to raise the fixed table 40 and bring it into close contact with the lower surface of the chamber 50, as shown in FIG. 4D, thereby sealing the target object 80. Furthermore, the control unit 70 opens the on-off valve 61 of the exhaust pipe 60 and the on-off valve 66 of the purge pipe 65 to exhaust the purge gas into the chamber 50 while purging it.

[0031] Next, the control unit 70 drives the articulated robot 30 to cause the articulated robot 30 to execute the operation that has been taught to the articulated robot 30 in advance. Specifically, first, the robot arm 32 of the articulated robot 30 is adjusted so that the first spot lamp heater 10a can irradiate the first soldering point P1 of the target object 80. When the control unit 70 receives a report from the articulated robot 30 that this positioning is complete, as shown in FIG. 4E, the control unit 70 energizes the first spot lamp heater 10a to turn it on, and further opens the shutter 20 for the first spot lamp heater 10a to irradiate the emitted light through the transparent window 51 to the first soldering point P1. This melts the cream solder applied to the land of the circuit board 81, and the electronic component 82a is soldered to the circuit board 81. After a predetermined time has elapsed, the shutter 20 is closed, and the first spot lamp heater 10a is turned off to turn it off. Next, the robot arm 32 of the articulated robot 30 is adjusted so that the second spot lamp heater 10b can irradiate the second soldering point P2 of the object 80. When the control unit 70 receives a report from the articulated robot 30 that the positioning has been completed, the control unit 70 energizes the second spot lamp heater 10b to turn it on, as shown in FIG. 4F, and further opens the shutter 20 for the second spot lamp heater 10b to irradiate the emitted light through the transparent window 51 to the second soldering point P2. As a result, the cream solder applied to the land of the circuit board 81 melts, and the electronic component 82b is soldered to the circuit board 81. After a predetermined time has elapsed, the shutter 20 is closed, and the second spot lamp heater 10b is turned off to turn it off.

[0032] By repeating this operation, when soldering of each soldering point is completed, the control unit 70 closes the opening / closing valve 61 of the exhaust pipe 60, confirms with a pressure sensor (not shown) that the pressure inside the chamber 50 has reached atmospheric pressure, closes the opening / closing valve 66 of the purge pipe 65, and lowers the fixing base 40 as shown in FIG. 4C. Next, as shown in FIG. 4B, the control unit 70 releases the clamp mechanism 42, raises the lift pins 43, and communicates with an external transfer robot (not shown), which then carries the target object 80 out.

[0033] When welding is performed using the heating device 1, the same operations as those for soldering are performed, except that the heated points are the butt joints between the workpieces to be welded, instead of the soldering points, and the applied irradiation energy is also different.

[0034] According to this embodiment, by adopting a spot lamp heater 10 including an inexpensive heating lamp 11, it is possible to realize a high temperature at which spot soldering and welding can be performed. Therefore, by combining with an articulated robot 30, it is possible to flexibly respond to changes in the object 80 to be soldered or welded, and an energy-saving and inexpensive heating device can be provided.

[0035] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to such specific examples, and various modifications and variations are possible within the scope of the gist of the present invention described in the claims.

[0036] For example, in the above embodiment, a halogen lamp is used as the heating lamp 11, but, for example, a xenon lamp may also be used.

[0037] Furthermore, the heating device 1 in the above embodiment has two spot lamp heaters 10a, 10b having different spot sizes at the focus f1 (see Figure 2) of the focusing optical system 12, but may have three or more spot lamp heaters 10, or may have only one spot lamp heater 10.

[0038] Furthermore, the heating device 1 of the above embodiment includes the shutter 20 that blocks and opens the light emitted from each spot lamp heater 10, but depending on the response time required during heating, the shutter 20 may not be provided.

[0039] Further, the heating device 1 in the above embodiment includes the fixing base 40 on which the preheater 44 is provided, but may include a fixing base 40 without the preheater 44, or may include a fixing mechanism other than the fixing base 40.

[0040] Furthermore, the heating device 1 of the above embodiment includes a chamber 50 that seals the object 80, has a transparent window 51 through which the emitted light passes, and is configured so that the inside can be evacuated; however, depending on the object 80 and the heating conditions, this chamber 50 may not be provided. [Industrial Applicability]

[0041] The heating device according to the present invention can be widely used in industrial fields where soldering and welding are performed. [Explanation of symbols]

[0042] 1: Heating device 10: Spot lamp heater 10a: First spot lamp heater 10b: Second spot lamp heater 11: Halogen lamp (heating lamp) 12: Focusing mirror (focusing optical system) 20: Shutter 21: Rotary actuator 22: Shutter blade 30: Articulated robot 31: Foundation 32: Robot arm 32a:Tip 40:Fixed stand 41: Pedestal 42: Clamping mechanism 43: Lift pin 44: Preheater 45: Lifting mechanism 50: Chamber 51: Transparent window 60: Exhaust pipe 61: Opening and closing valve 65: Purge piping 66: Opening and closing valve 70: Control section 80: Object 81: Circuit board 82a, 82b: Electronic components E: Elliptical sphere J1~J3: Bending joints P1: First solder point P2: Second solder point T1~T3: Axis f0,f1 :focal point

Claims

1. A heating device for use in soldering or welding, comprising: one or more spot lamp heaters including a heating lamp and focusing optics; an articulated robot for controlling the position and direction of the spot lamp heater; Including, A heating device comprising: a light collecting optical system that collects light emitted from the heating lamp of the spot lamp heater to a predetermined spot size and irradiates and heats an object; A heating device comprising a plurality of spot lamp heaters each having a different spot size at the focus of the light collecting optical system, and capable of using different spot lamp heaters depending on the location to be heated.

2. 2. The heating device according to claim 1, wherein the heating lamp is a halogen lamp or a xenon lamp.

3. 2. The heating device according to claim 1, further comprising a shutter for opening and closing an optical path of the light emitted from said spot lamp heater, said shutter being capable of controlling an exposure time of the heating location by opening and closing said shutter.

4. 2. The heating device according to claim 1, further comprising a fixing table for fixing the object, the fixing table being provided with a preheater for preheating the object.

5. 5. The heating device according to claim 4, further comprising: a chamber for sealing the object fixed to the fixing table and having a transparent window; an exhaust pipe for exhausting the inside of the chamber; and a purge pipe for introducing a purge gas into the inside of the chamber, wherein light emitted from the spot lamp heater is irradiated onto the object through the transparent window of the chamber, and the inside of the chamber is configured to be able to be exhausted.

6. 13. A soldering method comprising the steps of: applying solder to a land portion of an electronic board in advance; placing an electronic component thereon; and heating the solder using the heating device according to claim 1 to perform reflow soldering.

7. A welding method for heating and welding a butted portion of workpieces to be welded together using the heating device according to claim 1.

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