JP2002057174A - Method and apparatus for heat hardening electronic component sealing material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and apparatus for heat hardening an electronic component sealing material which can reduce the hardening time of the sealing material to provide a good productivity. SOLUTION: A belt conveyer 14 sends works 12 each having electronic components put in a package and sealed with a sealant to a preheating chamber 22 of a preheating furnace 20 for preheating the works with hot air. The conveyer 14 then sends the preheated works 12 to a superheated steam heating furnace 40 for superheating them with superheated steam which stores much heat to be conducted to the works 12 by convection and radiation. Thus, the works 12 are effectively heated for a very short time. The works 12 heated with superheated steam are sent to a dew-proof furnace 60. Hot air shuts the superheated steam off outside air to prevent the superheated steam from dewing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for thermosetting a sealing material such as silicone gel or epoxy resin for sealing electronic components.

[0002]

2. Description of the Related Art For example, a halogen lamp or the like is conventionally used as a light source for a vehicle headlight.
Intensity Discharge (High Intensity Discharge Lamp) has begun to be used. This HID requires a high voltage at the start of lighting. For this reason, at the start of lighting, an electronic component for controlling the driving power so as to generate a high voltage to rapidly raise the light output and to stabilize the power and to maintain a constant power is attached.
The package of this electronic component is sealed with a sealing material because of the necessity of protecting the electronic circuit from water, dust, and the like. As a sealing material, thermal conductivity is required from the viewpoint of suppressing a rise in temperature of electronic components, and insulation is required from the viewpoint of preventing a short circuit between electronic components. Silicon gel, epoxy resin,
Urethane or the like is used.

FIG. 5 shows a conventional thermosetting method of a sealing material. The electronic component 100 is set in an appropriate package 102, as shown in FIG. After that, as shown in FIG. 5B, the sealing material 106 is filled into the package 102 from the nozzle 104. Next, as shown in FIG. 5C, the package 102 filled with the sealing material 106 is sent to a hot blast stove 110 by a conveyor 108. In the hot blast stove 110, air at a predetermined temperature is generated, and this is the sealing material 1 of the package 102.
06 is sprayed. Thereby, the heat curing of the sealing material 106 is performed. The temperature of the hot air and the time of passing through the furnace are appropriately adjusted so that desired curing is performed.

[0004]

However, in the above background art, a considerable time is required until the sealing material is cured. For example, when a silicone gel is used as a sealing material, when the temperature of hot air is set to 120 ± 5 ° C.,
60 minutes or more are required. Of course, the curing time can be shortened by increasing the temperature of the hot air, but when the temperature is increased, the electronic components may be deteriorated.

The present invention has been made in view of the above points, and an object of the present invention is to provide a thermosetting method and an apparatus which can shorten the hardening time of a sealing material and have high productivity.

[0006]

In order to achieve the above object, the present invention relates to a thermosetting method for heating and curing a sealing material for an electronic component, the method comprising heating a work filled with the sealing material. A step of heating with steam; a step of preventing condensation of the superheated steam.

The present invention relates to a thermosetting apparatus for heating and hardening a sealing material of an electronic component, comprising: a superheated steam heating means for heating a work filled with the sealing material with superheated steam; Means for preventing condensation of superheated steam used in the means. One of the main modes is characterized in that a preheating means for preliminarily heating the work before heating it with superheated steam is provided. Another embodiment is characterized in that the preheating means also serves as the dew condensation preventing means. In another embodiment, the electronic component is a drive control circuit for a vehicle lamp. The above and other objects, features and advantages of the present invention will become apparent from the following detailed description and the accompanying drawings.

[0008]

<Embodiment 1> An embodiment of the present invention will be described in detail below. FIG. 1 shows a thermosetting apparatus according to Embodiment 1 of the present invention. In the figure, the thermosetting apparatus 10 has a configuration in which a preheating furnace 20, a superheated steam heating furnace 40, and a dew condensation prevention furnace 60 are successively arranged in that order. The work 12 of the electronic component package filled with the above-described sealing material is placed on a belt conveyor 14 and is sent from the preheating furnace 20 side to the thermosetting device 10, and the thermosetting device 10 Sent out from.

First, the preheating furnace 20 will be described. In the preheating chamber 22, a hot air nozzle 24 is provided above, on the side of, or below the conveyor, from which hot air is discharged to the work 12. ing. This hot air nozzle 24 is connected to an air heating device 28 via a fan 26. The air heated by the air heating device 28 is
The pressure is increased by the fan 26 and supplied to the hot-air nozzle 24, from which it is discharged as hot air into the preheating chamber 22. An exhaust duct 30 is provided below, beside, or above the conveyer of the preheating chamber 22 (facing the hot air nozzle 24), and the exhaust duct 30 is connected to the air heating device 28. That is, the air that has heated the work 12 in the preheating chamber 22 is sent from the exhaust duct 30 to the air heating device 28, where it is heated again and supplied to the preheating chamber 22.

Next, the superheated steam heating furnace 40 will be described. In the main heating chamber 42, a steam nozzle 44 is provided above or on the side of the conveyor, from which the superheated steam is discharged to the work 12. ing. The steam nozzle 44 is connected to a superheated steam generator 46, and a boiler 48 is connected to the superheated steam generator 46. The steam generated by the boiler 48 is supplied to a superheated steam generator 46 and becomes superheated steam. The generated superheated steam is supplied to a steam nozzle 44, from which the main heating chamber 42
It is discharged into. A collection duct 50 is provided below the conveyor of the main heating chamber 42.
Is connected to the superheated steam generator 46 via a pump 51. That is, the superheated steam that has heated the work 12 in the main heating chamber 42 is collected by the collection duct 50 by the pump 51 and sent to the superheated steam generator 46, where it is heated again and recycled.

Next, the dew condensation preventing furnace 60 has substantially the same configuration as the preheating furnace 20 described above. That is, the auxiliary heating chamber 62 is provided with a hot air nozzle 64 above, on the side of, or below the conveyor, from which hot air is discharged to the work 12. This hot air nozzle 64 is connected to an air heating device 68 via a fan 66. The air heated by the air heating device 68 is
The pressure is increased by the fan 66 and supplied to the hot air nozzle 64, from which the hot air is discharged into the auxiliary heating chamber 62 as hot air. An exhaust duct 70 is provided below, on the side of, or above the conveyer of the auxiliary heating chamber 62 (facing the hot air nozzle 64), and the exhaust duct 70 is connected to the air heating device 68. That is, the air that has heated the work 12 in the auxiliary heating chamber 62 is sent from the exhaust duct 70 to the air heating device 68, where it is heated again and supplied to the auxiliary heating chamber 62.

The above-described preheating furnace 20 and dew condensation preventing furnace 6
As 0, a known hot blast stove can be applied. The same applies to the superheated steam heating furnace 40, which includes a superheated steam generator 46.
Also, various known types may be used, but a preferred example is shown in FIG. In the drawing, in a heating tank 300, partition walls 302 made of a heat storage material (for example, a ceramic heat storage plate) are provided alternately at predetermined intervals, whereby a serpentine passage 304 is formed in the heating tank 3.
00. A heater 306 is provided so as to penetrate the partition wall 302 and cross the passage 304. Further, the passage 304 is provided with a corrosion-resistant metal wire (or metal piece) 308 and a ceramic piece 3.
A heat storage body 312 in which 10 are randomly entangled is filled. Similarly, a material that does not rust, such as stainless steel or titanium, is used as the metal wire 308. The outside of the heating tank 300 is covered with a heat insulating material 314.

When the heater 306 generates heat by energization, the heating tank 300 is heated from the inside, and the partition 302 formed of the heat storage material and the heat storage 312 in the passage 304 are also heated. In this state, steam is supplied from the boiler 48 to the heating tank 3.
When the steam is supplied to the inlet 316 of
06, and becomes superheated steam from normal steam. Moreover, the superheated steam is stored in the heat storage body 31 in the passage 304.
2, or hits the partition 302, so that it is discharged from the discharge port 318 of the heating tank 300 while maintaining a high temperature state.

Next, the overall operation of this embodiment will be described. The work 12 in which the electronic components are stored in the package and filled with the sealing material is first sent to the preheating chamber 22 of the preheating furnace 20 by the belt conveyor 14. And
Preheating with hot air is performed in the preheating chamber 22.
For example, preheating is performed at a temperature of 120 ± 5 ° C. for about 10 minutes.

Next, the workpiece 12 after the preheating is sent to the superheated steam heating furnace 40 by the belt conveyor 14, and is heated by the superheated steam. The preheating described above is performed on the work 12, and the work 12 is at a considerably high temperature. The superheated steam has accumulated a large amount of heat, and this heat is also transmitted to the work 12 by convection (in some cases, radiation). Therefore, the work 12 is effectively heated within a very short time, and the temperature rises.
Thereby, the thermosetting of the sealing material of the work 12 is efficiently performed. 120 ± even in the superheated steam heating furnace 40
Heating is performed at a temperature of 5 ° C. for about 10 minutes.

Next, the work 1 after the main heating by the superheated steam
2 is sent to the dew condensation prevention furnace 60. The superheated steam has a property of rapidly decreasing its temperature, and when the temperature decreases, dew condensation occurs. Dew condensation on the work 12 causes problems such as short-circuiting of the extraction electrode. Therefore, the work 12 heated by the superheated steam is not directly sent out into the air, but is sent into the dew condensation preventing furnace 60. Then, the contact between the superheated steam and the outside air is cut off by the hot air, and the temperature of the superheated steam is prevented from lowering. Such a situation is the same on the preheating furnace 20 side. Thereby, dew condensation of the superheated steam is favorably prevented. In the dew condensation preventing furnace 60, heating is performed at a temperature of 100 ± 5 ° C. for about 5 minutes. Since it is only necessary to prevent dew condensation, the temperature may be lower than that of the preheating furnace 20 or the superheated steam heating furnace 40,
In addition, a short time is sufficient.

As described above, according to the present embodiment, the dew condensation preventing furnace 6 is switched from the preheating furnace 20 through the superheated steam heating furnace 40.
The processing time of the process reaching 0 becomes about 25 minutes. On the other hand, according to the background art described above, a minimum of 60 minutes is required, and it is apparent from comparison between the two that the curing time is greatly reduced and the productivity is improved according to the present embodiment.

<Second Embodiment> Next, a second embodiment will be described with reference to FIG. Embodiment 1 described above
Although the hot-blast stove and the superheated steam heating furnace are separately configured in this embodiment, the present embodiment is configured to introduce superheated steam into the hot-blast stove. Note that the same reference numerals are used for components corresponding to those in the first embodiment.

In FIG. 3, hot air is supplied to a heating chamber 502 of a thermosetting device 500 by a fan 506 from an air heating device 504. This hot air is supplied to the heating chamber 502.
Are discharged into the heating chamber 502 by hot air nozzles 508 provided on the work entrance side and the work exit side, respectively. On the other hand, in the superheated steam generator 510, the boiler 512
Is heated to generate superheated steam. This superheated steam is discharged into the heating chamber 502 from a steam nozzle 514 provided near the center of the heating chamber 502. The air in the heating chamber 502 is exhausted from the exhaust duct 520 and sent to the dryer 522 to be dried. In the case of the present embodiment, the heating chamber 502
The air inside becomes moist. Therefore, dryer 5
After drying the air at 22, the air is supplied to the air heating device 504.

The operation of this embodiment is the same as that of the first embodiment.
As described above, the curing time of the sealing material of the work 12 is greatly reduced. Also, dew condensation of the superheated steam is well prevented since the superheated steam is sandwiched by the hot air. In the present embodiment, the hot air and the superheated steam are mixed in the heating chamber 502. However, since the air-fuel mixture is heated after being dried by the dryer 522, no inconvenience occurs.

The present invention has many embodiments, and can be variously modified based on the above disclosure. For example, the following is also included. (1) As a thermosetting sealing material to which the present invention is applied,
The present invention can be applied not only to the above-described silicone-based or epoxy-based thermosetting resins, but also to various types, for example, urethane-based thermosetting resins. Further, the present invention can be applied to various electronic components in addition to a drive control circuit of a vehicle lamp. (2) In the illustrated embodiment, the example in which the hot air nozzle is provided above the conveyor is illustrated, but it may be provided on the side or below the conveyor. In this case, it is convenient to provide the exhaust duct on the side facing the hot air nozzle.

(3) In the above embodiment, as shown in FIG. 4 (A), the preheating furnace 20 → the superheated steam heating furnace 40 → the connection prevention furnace 60 has a structure. The heating furnace 20 includes a preheating furnace 20 as shown in FIG.
A and the dew condensation prevention furnace 20B are also used. Therefore, as shown in the figure, the preheating furnace 20A and the dew condensation preventing furnace 20B may be separately provided. Further, in the case where the thermosetting is performed only by the superheated steam without performing the preheating by the preheating furnace 20A, as shown in FIG.
The dew condensation prevention furnaces 20B and 60 are provided before and after the superheated steam heating furnace 40, respectively. (4) In the above embodiment, a hot blast stove was used for preheating and dew condensation prevention, but any heating stove may be used as long as it is a heating stove. For example, an IR furnace or the like may be used as the preheating furnace.

[0023]

As described above, according to the present invention,
Since the thermal curing of the electronic component sealing material is performed using the superheated steam, there is an effect that the curing time of the sealing material can be shortened and the productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a first embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of a superheated steam generator.

FIG. 3 is a diagram showing a configuration of a second embodiment of the present invention.

FIG. 4 is a diagram showing an example of a configuration of the present invention.

FIG. 5 is a view showing filling of an electronic component with a sealing material and a conventional method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Thermosetting apparatus 12 ... Work 14 ... Belt conveyor 20 ... Preheating furnace 22 ... Preheating chamber 24 ... Hot air nozzle 26 ... Fan 28 ... Air heating apparatus 30 ... Exhaust duct 40 ... Superheated steam heating furnace 42 ... Main heating chamber 44 ... Steam nozzle 46 ... Superheated steam generator 48 ... Boiler 50 ... Recovery duct 51 ... Pump 60 ... Condensation prevention furnace 62 ... Auxiliary heating chamber 64 ... Hot air nozzle 66 ... Fan 68 ... Air heating device 70 ... Exhaust duct 100 ... Electronic component 102 ... Package 104 ... Nozzle 106 ... Sealant 108 ... Conveyor 110 ... Hot stove 300 ... Heating tank 302 ... Partition wall 304 ... Path 306 ... Heater 308 ... Metal wire 310 ... Ceramic piece 312 ... Heat storage element 314 ... Heat insulator 316 ... Inlet 318: discharge port 500: thermosetting device 502: heating chamber 504: air heating device 06 ... Fan 508 ... hot air nozzle 510 ... superheated steam generator 512 ... boiler 514 ... steam nozzle 520 ... exhaust duct 522 ... dryer

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Hisano Murai 500 Kitawaki, Shimizu City, Shizuoka Prefecture Koito Manufacturing Co., Ltd. Shizuoka Plant (72) Inventor Kosaku Morishita 500 Kitawaki Shimizu City, Shizuoka Prefecture Koito Manufacturing Shizuoka Plant F Terms (reference) 4F204 AA33 AA39 AD02 AH37 AK01 EB01 EB11 EE06 EF05 EK13 EK17 5F061 AA01 BA01 CB02 DA00 FA06

Claims (5)

[Claims] 1. A method of heating and curing a sealing material of an electronic component, comprising: heating a work filled with the sealing material with superheated steam; and preventing condensation of the superheated steam. A thermosetting method for an electronic component sealing material, comprising: 2. A thermosetting apparatus for heating and curing a sealing material of an electronic component, comprising: a superheated steam heating means for heating a work filled with the sealing material with superheated steam; A device for preventing condensation of superheated steam to be used; 3. The thermosetting apparatus for an electronic component sealing material according to claim 2, further comprising a preheating means for preheating the workpiece before heating the workpiece with superheated steam. 4. The thermosetting apparatus for an electronic component sealing material according to claim 3, wherein said preheating means also serves as said dew condensation preventing means. 5. The thermosetting device for an electronic component sealing material according to claim 2, wherein the electronic component is a drive control circuit of a light source for a vehicle.