Claims
- 1. A soldering apparatus for soldering an electronic component to a printed circuit board by heating the printed circuit board having the electronic component mounted thereon, the apparatus comprising:
- a preheating zone; and
- a reflow zone located downstream from the preheating zone, and
- the preheating zone having first and second heaters, the first heater adapted to emit far-infrared energy which primarily heats the printed circuit board and the second heater adapted to emit near-infrared energy which primarily heats the electronic component.
- 2. A soldering apparatus as set forth in claim 1, wherein the reflow zone has a third heater.
- 3. A soldering apparatus as set forth in claim 1, wherein the preheating zone includes a pair of first heaters and a pair of second heaters, the heaters of each pair being arranged to face opposing sides of the printed circuit board.
- 4. A soldering apparatus as set forth in claim 1, wherein the first heater presents a radiation spectrum having a maximum peak at a wavelength greater than 2.5 .mu.m and the second heater presents a radiation spectrum having a maximum peak at a wavelength less than 2.5 .mu.m.
- 5. A soldering apparatus as set forth in claim 1, wherein the first heater presents a radiation spectrum having a maximum peak in a wavelength range of from 5 .mu.m to 8 .mu.m.
- 6. A soldering apparatus as set forth in claim 1, wherein the second heater presents a radiation spectrum having a maximum peak in a wavelength range of from 1 .mu.m to 2 .mu.m.
- 7. A soldering apparatus as set forth in claim 1, further comprising a transporting mechanism for transporting the printed circuit board from the preheating zone to the reflow zone.
- 8. A soldering process for soldering an electronic component to a printed circuit board by heating the printed circuit board having the electronic component mounted thereon, the process comprising:
- (a) preheating the electronic component and the printed circuit board to a first temperature in a preheating zone by primarily heating the printed circuit board with a first heater and primarily heating the electronic component with a second heater, the first and second heaters being far-infrared and near-infrared heaters, respectively; and
- (b) after step (a), heating the electronic component and the printed circuit board to a second temperature higher than the first temperature in a reflow zone by primarily heating the printed circuit board with a first heater and primarily heating the electronic component with a second heater.
- 9. A soldering process as set forth in claim 8, further comprising the step of (c) maintaining the electronic component and the printed circuit board at the first temperature before heating to the second temperature.
- 10. A soldering process as set forth in claim 8, wherein the first temperature is in a range of from 130.degree. C. to 160.degree. C.
- 11. A soldering process as set forth in claim 8, wherein solder having a melting point is used to solder the electronic component to the printed circuit board and the second temperature is higher than the melting point of the solder.
- 12. A panel heater used in an apparatus for soldering an electronic component to a printed circuit board, the panel heater comprising:
- a heat conduction layer having a first coefficient of thermal expansion and first and second sides;
- a heating element disposed on the first side of the heat conduction layer for heating the heat conduction layer;
- a radiation layer disposed on the second side of the heat conduction layer for receiving heat from the heat conduction layer and emitting infrared radiation, the radiation layer having a second coefficient of thermal expansion; and
- a buffer layer disposed between the heat conduction layer and the radiation layer and having a coefficient of thermal expansion between the first and second coefficients of thermal expansion.
- 13. A panel heater as set forth in claim 12, wherein the radiation layer is formed of aluminum oxide, the heat conduction layer is formed of aluminum and the buffer layer is formed of nichrome.
- 14. A panel heater as set forth in claim 12, wherein the heat conduction layer and the buffer layer are formed by flame-spraying.
- 15. A panel heater as set forth in claim 12, wherein the radiation layer has a surface roughness of about 2 .mu.m or less.
- 16. A panel heater as set forth in claim 12, wherein the heat conduction plate has a thermal conductivity of at least 50 w/m .multidot..degree. K.
- 17. A panel heater as set forth in claim 12, wherein the heat conduction layer is made of a material selected from the group consisting of aluminum, molybdenum, copper, graphite and aluminum nitride.
Priority Claims (4)
Number |
Date |
Country |
Kind |
5-265281 |
Oct 1993 |
JPX |
|
5-266690 |
Oct 1993 |
JPX |
|
6-045798 |
Mar 1994 |
JPX |
|
6-135926 |
Jun 1994 |
JPX |
|
Parent Case Info
This application is a continuation of application Ser. No. 08/327,907, filed Oct. 24, 1994, now U.S. Pat. No. 5,607,609.
US Referenced Citations (22)
Foreign Referenced Citations (17)
Number |
Date |
Country |
0 279011 |
Aug 1988 |
EPX |
0 368080 |
May 1990 |
EPX |
89 06 375 |
May 1989 |
DEX |
42 38 597 |
May 1994 |
DEX |
4238597 |
May 1994 |
DEX |
59-181092 |
Oct 1984 |
JPX |
61-79293 |
Apr 1986 |
JPX |
62-124084 |
Jun 1986 |
JPX |
62-31147 |
Feb 1987 |
JPX |
62-144876 |
Jun 1987 |
JPX |
62-203669 |
Sep 1987 |
JPX |
63-123593 |
Oct 1988 |
JPX |
1-254383 |
Oct 1989 |
JPX |
1254383 |
Nov 1989 |
JPX |
2-144990 |
Jun 1990 |
JPX |
3-214688 |
Sep 1991 |
JPX |
4-209671 |
Jul 1992 |
JPX |
Continuations (1)
|
Number |
Date |
Country |
Parent |
327907 |
Oct 1994 |
|