Terminal-carrying circuit board

• US 5,656,798 A
• Filed: 12/19/1995
• Issued: 08/12/1997
• Est. Priority Date: 09/21/1992
• Status: Expired due to Term

• Current Assignee: Panasonic Electric Works Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Asahi Matsushita Electric Works Ltd. (Panasonic Holdings Corporation)
• Inventors: Kamada, Kazuo, Kubo, Masao, Nakamura, Yoshimitsu, Ogasawara, Masanobu
• Primary Examiner(s): Thomas, Laura
• Application Number:
  US08/574,855
• Time in Patent Office: 602 Days
• Field of Search: 174/262, 174/263, 174/264, 174/265, 174/266, 257/694, 257/739, 257/734, 361/772, 361/773, 361/774, 439/45, 439/46, 439/75, 439/81, 439/82, 439/83, 439/84
• US Class Current: 174/265
• CPC Class Codes: H01L 21/486 Via connections through the substrate with or without pins
• CPC Class Codes: H01L 2924/15312 being a pin array, e.g. PGA
• CPC Class Codes: H01R 12/523 by an interconnection through aligned holes in the boards or multilayer board
• CPC Class Codes: H01R 12/58 terminals for insertion into holes
• CPC Class Codes: H01R 43/0221 Laser welding H01R43/0228 takes precedence
• CPC Class Codes: H01R 43/0235 for applying solder H01R43/0228 takes precedence
• CPC Class Codes: H05K 2201/10303 Pin-in-hole mounted pins
• CPC Class Codes: H05K 2201/10871 Leads having an integral insert stop
• CPC Class Codes: H05K 2201/10984 Component carrying a connection agent, e.g. solder, adhesive soldering leadless components having an array of bottom contacts H05K3/3436; BGA components H05K2201/10734
• CPC Class Codes: H05K 2203/107 Using laser light shaping a substrate by laser ablation H05K3/0026
• CPC Class Codes: H05K 3/3447 Lead-in-hole components H05K3/3415 takes precedence
• CPC Class Codes: H05K 3/3494 Heating methods for reflowing of solder using integral heating means H05K1/0212
• CPC Class Codes: Y10T 29/49149 by metal fusion bonding
• CPC Class Codes: Y10T 29/49153 with shaping or forcing terminal into base aperture

Abstract

A circuit board has holes extending therethrough, and a solder layer disposed on a first side of the board. Terminals have been pushed through respective holes and into contact with the solder layer. The terminals have been welded to the first side of the circuit board in a fluxless manner by an irradiated energy beam.

Claims

1. A terminal-carrying circuit board structure comprising a circuit board and terminals installed therein, the circuit board including through-holes formed therein for the installation of respective terminals, each through-hole including a conductive inner wall surface having a first pre-installation lining of solder formed thereon, each terminal including first and second ends, said first end having a second pre-installation lining of solder formed thereon, said first and second pre-installation linings forming respective first and second tightly contacting lining surfaces each being scratched in response to installation of the terminal first part into its respective through hole, said first and second lining surfaces being thermally joined together by energy beam irradiation.

2. The terminal-carrying circuit board structure according to claim 1, wherein each of the through holes includes first and second ends, said first end defining a terminal-inlet end into which a leading end of a respective terminal is inserted, each terminal including a flange having a stop surface facing said terminal inlet end to limit an extent of installation of said terminal into its respective through hole.

3. The circuit board structure according to claim 1, wherein said terminals respectively have an end thereof formed for causing a multipath reflection of said energy beam irradiated thereon.

4. The circuit board structure according to claim 1, wherein said terminals respectively have recesses and projections at an end thereof which is irradiated by said energy beam for causing a multipath reflection of said energy beam.

5. The circuit board structure according to claim 2, wherein said terminals respectively have longitudinal recesses and projections at an end thereof which is irradiated by said energy beam and radial recesses and projections at said flange and corresponding to said longitudinal recesses and projections.

6. The circuit board structure according to claim 2, wherein said flange of each terminal extends laterally outwardly from a central part of the terminal, an outer peripheral of said terminal being thinner than said central part.

7. A multi-layer, terminal-carrying circuit board structure, comprising a plurality of circuit boards and terminals installed therein, said circuit boards being provided with circuit patterns including interlayer circuit patterns and with through holes formed through respective circuit patterns, each through hole having a first pre-installation lining of solder covering an inner peripheral wall thereof and connected to the circuit pattern, each of said through holes including first and second ends, said first end defining a terminal-inlet end into which a leading end of a respective terminal is inserted, each terminal including a flange having a stop surface facing said terminal inlet end to limit an extent of installation of said terminal into its respective through hole, each terminal including its flange being covered by a second pre-installation lining of solder, said first and second pre-installation linings forming respective first and second tightly contacting surfaces each being scratched in response to installation of the terminal into its respective through hole, said first and second scratched lining surfaces being thermally joined together by energy beam irradiation.