JPH04113184U - light heating device - Google Patents

Abstract

(57) [Summary] [Purpose] In a light irradiation device that uses optical fibers to increase flexibility, it is possible to check before the start of light irradiation whether the output part of the optical fiber is placed in a position where it can irradiate the desired location. By providing a means to monitor the temperature in advance, it is possible to prevent erroneous heating that should not be performed. [Structure] When the shutter plate 41 is placed on the optical path, light from the light source 2 enters the shutter plate 41 for blocking light on the optical path before it enters the input end face 31 of the optical fiber 3. A minute light transmission hole 410 is provided, and by monitoring the irradiation position of leaked light from this light transmission hole 410, the output portion 34 of the optical fiber 3 is positioned in advance at an optimal position.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is an optical heating device that performs radiant heating using light. This invention relates to optical heating devices used in industrial processes such as the following.

0002

[Conventional technology]

Heating objects by radiant heating using light has been practiced for a long time, but recently It also has many applications in industrial processes. For example, soldering electronic components to printed wiring boards, curing thermosetting resin, It also covers a wide range of areas, including welding plastics.

0003 Radiant heating using light is preferably used for Since heating can be performed without contact, there is no risk of contamination of the heated object. You can heat only the parts you want to heat. Good controllability. It can be heated instantly. This is because of the following reasons.

0004 The above-mentioned optical heating device must be able to freely heat a desired location away from the light source. Due to these demands, recently optical fibers have been developed that condense the light from the light source. An optical heating device is known in which light is introduced into an optical fiber and irradiated by being guided by the optical fiber. Ru. In addition, soldering is performed during the mounting process of electronic components such as LSI on printed wiring boards. In order to improve mounting density, the area of soldering points has become smaller. According to the optical heating device using the above-mentioned optical fiber, only a very small area can be heated. It has come to be widely used because it can heat the water.

[0005] FIG. 4 is a schematic explanatory diagram of a conventional optical heating device using an optical fiber. Figure 4 The optical heating device includes an elliptical condensing mirror 1 and a light emitting section 21 located at the first focal point 10 of the elliptical condensing mirror 1. The light source 2 is arranged so that the incident end face 31 is the second focal point of the elliptical condensing mirror 1. The optical fiber 3 arranged at the position 15 and the input end surface 3 of the optical fiber 3 Consisting of a shutter plate 41, etc. that blocks light on the optical path before it enters 1. be done. In the optical heating device shown in FIG. 15, and from the incident end face 31 located at the second focal point 15. The light enters the optical fiber 3. The incident light is then guided by the optical fiber 3. After that, the radiation is emitted from the output end face 36 and irradiates the object to be heated 8, so that the object to be heated 8 is heated. Ru.

[0006] The above light heating device uses optical fiber 3, so the light irradiation location is not limited. Excellent flexibility. Furthermore, the emission section 34 includes an X-Y movement mechanism and a robot arm. Efforts have also been made to increase versatility by adding features such as:

[0007]

[Problem that the idea aims to solve]

As mentioned above, optical heating devices using optical fibers do not have a fixed area to irradiate with light. By moving the output part of the optical fiber, you can locate the desired location away from the light source. It has the advantage of free heating and is therefore easy to integrate into existing automated processes. It has the advantage of being

[0008] However, by taking advantage of the characteristics of optical fiber, various heating points can be heated without fixing them. When changing the location to the desired location, check the output of the optical fiber in advance before starting light irradiation. It is necessary to monitor whether the irradiation unit has been positioned to irradiate the desired position.

[0009] However, in conventional devices, the position of the emitting part must be set to the desired position before starting light irradiation. There is no way to monitor whether or not the heat is placed in the correct position, and the Sometimes I ended up irradiating it. For example, when an X-Y moving mechanism is attached to the output part of an optical fiber to move the output part. In addition, the mounting position of the emission part with respect to the X-Y movement mechanism and the operating status of the X-Y movement mechanism are There was no way to monitor before starting irradiation, and electronic parts that should not be heated could be mistakenly heated. This may cause damage due to overheating.

0010 The invention of this application was made to solve such problems, and In optical heating equipment that uses optical fibers to increase flexibility, the output part of the optical fiber is desired. Before starting light irradiation, monitor in advance whether the area is placed in a position where it can be irradiated. By providing a means to prevent accidental heating that should not be done. The purpose is to provide an optical heating device that can

[0011]

[Means to solve the problem]

In order to achieve the above object, the optical heating device according to claim 1 of the present application includes an elliptical condensing mirror and a light source having a light emitting part placed at the first focal point of the elliptical condenser; and an elliptical condenser. an optical fiber having an input end face disposed at the second focal point of the optical fiber; A shutter plate is used to block the light on the optical path in front of the The system is equipped with a shutter drive mechanism for placing it on the optical path and retracting it from the optical path. The shutter plate has a small amount of light that enters the light source when the shutter plate is placed on the optical path. It has a small number of light-transmitting holes.

0012 Further, the optical heating device according to claim 2 of the present application is the optical heating device according to claim 1, wherein: The light transmission hole is located on the optical axis when the shutter plate is placed on the optical path. It is located at the location.

[0013]

【Example】

Examples of the present invention will be described below. FIG. 1 is a schematic explanatory diagram of an optical heating device according to an embodiment of the present invention, and FIG. FIG. 2 is a perspective view of essential parts of the heating device. The optical heating device shown in Figures 1 and 2 is a bowl-shaped device installed so that the optical axis is horizontal. The light emitting unit 21 is located at the first focal point 10 of the elliptical condensing mirror 1 and the elliptical condensing mirror 1. The second focal point 15 of the elliptical condensing mirror 1 has a light source 2 provided as shown in FIG. The optical fiber 3 is arranged such that its input end face 31 is located at the position of The light incident on the surface 31 is blocked on the optical path near the light source 2 side of the entrance end surface 31. A shutter plate 41 for placing the shutter plate 41 on the optical path and retracting it from the optical path. The shutter drive mechanism 40 for avoiding the optical fiber 3 and the entrance part 32 of the optical fiber 3 are held. It is composed of an entrance section holder 5, a casing 6 for storing these components, etc. There is.

[0014] The elliptical condenser mirror 1 has its front aperture facing the input end face 31 of the optical fiber 3. It is held by a condensing mirror holder 11. This condensing mirror holder 11 is It is fixed to the inner surface of the ring 6.

[0015] In this embodiment, the light source 2 has a strong emission spectral distribution from the visible region to the infrared region. A xenon short arc lamp is used. This xenon show Since the light emitting part 21 of the tor lamp is small, it is focused on the second focal point by the elliptical condenser mirror 1. It can be focused into an extremely small beam of light. Therefore, as in this example, light It is suitable for a light source device using a fiber. The light source 2 made of this xenon short arc lamp has a spherical bulge in the center. A long tube body 22 having a diameter of 23 and a tube body 22 disposed facing each other inside the bulging portion 23 are Consisting of a pair of discharge electrodes 24 and caps 25 and 26 provided at both ends of the tube body 22 has been done. The space facing the discharge electrode 24 is the discharge part, that is, the light emitting part 21, and the space facing the discharge electrode 24 is the discharge part, that is, the light emitting part 21, The source 2 is arranged so that the light emitting part 21 is located at the first focal point 10 of the elliptical condenser mirror 1. It will be done.

[0016] That is, the light source 2 has one base 25 fixed to the lamp holder 27, and the light source 2 has one base 25 fixed to the lamp holder 27. The tube body 22 extends from the outlet 23 to the base 25 fixed to the lamp holder 27. The part is inserted through the bottom opening 12 provided at the bottom of the bowl-shaped elliptical condensing mirror 1. It is installed as follows. The lamp holder 27 has a three-dimensional position adjustment mechanism 28. The position of the light source 2 can be adjusted by operating this three-dimensional position adjustment mechanism 28. Furthermore, the position of the light emitting part 21 is adjusted three-dimensionally to bring the light emitting part 21 to the position of the first focal point 10. It is possible to place it anywhere. Note that the lamp holder 27 is connected to the light source 2. It has a power feeding part, and a lead wire 29 for power feeding is attached to the other base 26. I'm being kicked.

[0017] The optical fiber 3 has a flexible portion 33 covering the bundle with a flexible cover and a bundle. The input part 32 and the output part 34 have a structure in which both ends of the dollar are covered with non-flexible metal fittings, and It is composed of an output lens unit 35 that is connected to the output side of the output section 34 .

[0018] Further, the casing 6 at a position facing the light source 2 has an input section 32 for the optical fiber 3. A hole is provided for fixing the input part holder 5 to the casing 6. It is fixed to the casing 6 by being inserted into the hole. The entrance part 32 of the optical fiber 3 has a cylindrical shape, and the entrance part holder 5 It has a cylindrical shape so as to be able to hold the cylindrical incident section 32. This entrance holder -5 is a contact that has an inner diameter that almost matches the outer diameter of the incident part 32 and contacts the incident part 32. The part 55 has an inner diameter somewhat larger than the outer diameter of the entrance part 32, and when held, the entrance part 32 and A gap holding part 56 with a gap formed therebetween, and a terminal end of this gap holding part 56 closing the cylinder. 53. What is fixed to the casing 6 is This is the contact portion 55, and the gap holding portion 56 and the back wall 53 are located inside the casing 6. be placed. In addition, the gap holding part 56 allows cooling air to flow inside the entrance part holder 5. Ventilation holes 521 and 522 are provided to allow air to flow through the room. In addition, back wall 53 A window 531 is provided for introducing light into the incident end surface 31.

[0019] In addition, it is possible to penetrate the thick part of the entrance part holder 5 that is exposed outside the casing 6. The setscrews 51 are screwed together in such a manner as to be screwed together. The circumferential surface of the cylindrical entrance section 32 has an upper surface. The input part 32 of the recording optical fiber 3 is inserted into the holder, and the input end face 31 is placed in the input part holder. When it hits the back wall 53 of the driver 5, the tip of the set screw 51 enters and engages. A possible set screw recess 321 is provided. When holding the optical fiber 3 in this entrance part holder 5, the entrance part 32 is The entrance end face 31 of the front end is brought into contact with the back wall 53. this state Then, the entrance is adjusted so that the entrance end face 31 is located at the second focal point 15 of the elliptical condenser mirror 1. The part holder 5 is fixed to the casing 6 in a predetermined positional relationship with respect to the elliptical condenser mirror 1. ing. Therefore, the entrance end surface 31 should be brought into contact with the back wall 53 of the entrance section holder 5. Then, turn the set screw 51 to fit it into the set screw recess 321 of the input section 32. Optical positioning of the entrance end face 31 is performed. That is, the position of the second focal point of the elliptical condensing mirror 1 held in place.

[0020] The shutter drive mechanism 40 includes a shutter shaft 42 that pivotally supports a shutter plate 41, and a shutter shaft 42 that pivotally supports a shutter plate 41. The shutter plate 41 is swung around the shutter shaft 42 in a plane perpendicular to the optical axis. A rotary saw for arranging the shutter plate 41 on the optical path and retracting it from the optical path. It is composed of a lenoid 42. Then, the shutter shaft 42 and rotary solenoid The door 43 is attached to a mounting plate (not shown) fixed to the casing 6.

[0021] The shutter plate 41 receives light from the light source 2 when the shutter plate 41 is placed on the optical path. A minute light transmission hole 410 through which light enters is provided. This light transmission hole 410 is As characteristically shown in FIG. 2, when the shutter plate 41 is placed on the optical path, It is located at the location of The diameter of this light transmission hole 410 is about 2 mm. The light transmission hole 410 If the diameter becomes too large, parts other than the object to be heated 8 may be left unattended during the arrangement operation of the emitting part 34. The object to be heated 8 may be heated unnecessarily, or the object to be heated 8 may be heated considerably before being heated by the actual light irradiation. Since it may overheat, make it as small as possible so that it does not interfere with the monitor. light source 2 For example, it is preferably 3 mm or less, although it is related to the output of

[0022] The light transmitting hole 410 allows the shutter plate 41 to be placed on the optical path, allowing the light source 1 to Even when most of the light is blocked, a small amount of light leaks through the light transmission hole 410 and the light The light enters the fiber 3 and is irradiated onto the object to be heated 8 . Therefore, this irradiated leakage By using the reflected light, it is possible to monitor whether the output part 34 of the optical fiber 3 is at the desired position. I can do that.

[0023] In this embodiment, when the shutter plate 41 is located on the optical path, the light transmission hole 410 is located on the optical axis A, so it becomes the center of the beam on the irradiation surface. The position is irradiated with leaked light from this light transmission hole 410. Therefore, this leakage light The position of the emission part 34 is adjusted so that the irradiation position is centered on the area of the object to be heated 8 to be irradiated. It is easy to adjust the position.

[0024] Next, using Fig. 1, we will use this optical heating device to automatically manufacture electronic components such as LSI. An example of soldering will be explained below. Figure 3 shows the case where the optical heating device in Figure 1 is applied to an automatic soldering device for electronic components. It is a figure explaining an outline. The output portion 34 of the optical fiber 3 is fixed by a fixture (not shown). on the other hand , the printed wiring board 9 to be soldered is placed and fixed on the X-Y moving table 90. has been established.

[0025] When the processing is not started, the shutter plate 41 is on the optical path and does not block the light from the light source 2. Most of the area is blocked by the shutter plate 41. First, the X-Y moving table 90 is operated by a signal from the control device 91, and the Place the printed wiring board so that the area where the laser beam 8 is placed is at a predetermined position below the emission part 34. Move 9 horizontally. Then, the shutter plate 4 checks whether the exit lens unit 35 is located at a predetermined position. The operator monitors the light beam on the surface of the solder 8 caused by the leaked light from the light transmission hole 410 of 1. Check by typing. Note that automatic monitoring using an optical sensor may also be used. In this state, a drive signal is then sent from the control device 90 to the rotary solenoid 43. The shutter plate 41 is retracted from the optical path. As a result, the light is focused by the elliptical focusing mirror 1. The light from the light source 2 enters the optical fiber 3 from the input end face 31. incident light After being guided by the optical fiber 3, it is emitted from the output section 34, and is emitted from the output lens unit. After being focused again by the lens in the knit 35, it is irradiated onto the solder 8 and the solder 8 melts. After that, the shutter plate 41 is placed on the optical path again and the heating is stopped. The solder 8 cools and solidifies, completing the soldering.

[0026]

[Effect of the idea]

As explained above, according to the invention of claim 1 of the present invention, the output part of the optical fiber Before starting light irradiation, monitor whether the light is placed in a position where it can irradiate the desired area. By setting the temperature, you can prevent the product from accidentally heating when it should not be heated. I can do it. Further, according to the invention of claim 2, the position of the output part of the optical fiber can be easily adjusted. Become.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram of an optical heating device according to an embodiment of the present invention.

FIG. 2 is a perspective view of essential parts of the optical heating device in FIG. 1;

FIG. 3 is a diagram schematically illustrating a case where the optical heating device of FIG. 1 is applied to an automatic soldering device for electronic components.

FIG. 4 is a schematic explanatory diagram of a conventional optical heating device using an optical fiber.

[Explanation of symbols]

1 Elliptical condenser mirror 10 First focus 15 Second focus 2 Light source 3 Optical fiber 31 Incidence end face 34 Emitter 40 Shutter drive mechanism 41 Shutter board 410 Light transmission hole 5 Input part holder 8 Object to be heated

──────────────────────────────────────────────── ─── Continued from front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location G02B 26/02 B 7820-2K H01J 61/84 8019-5E H05B 3/00 345 8918-3K H05K 3 /34 T 9154−4E // B23K 101:42

Claims (2)

[Scope of utility model registration request] Claim 1: An elliptical collector mirror, a light source having a light emitting part located at a first focal point of the elliptical collector mirror, and an entrance end face located at a second focal point of the elliptical collector mirror. a shutter plate for blocking light on an optical path before it enters an input end face; and a shutter drive mechanism for arranging the shutter plate on the optical path and retracting the shutter plate from the optical path; A light heating device characterized in that the plate is provided with minute light transmission holes through which light from the light source enters when the shutter plate is placed on the optical path. 2. The optical heating device according to claim 1, wherein the light transmission hole is provided at a position such that it is located on the optical axis when the shutter plate is placed on the optical path. A light heating device.