Printed circuit board inspection apparatus

• US 5,107,206 A
• Filed: 05/20/1991
• Issued: 04/21/1992
• Est. Priority Date: 05/25/1990
• Status: Expired due to Fees

• Current Assignee: Tescon Co., Ltd.
• Original Assignee: Tescon Co., Ltd.
• Inventors: Ikeda, Keiichi, Yanagi, Kunio
• Primary Examiner(s): Wieder, Kenneth A.
• Assistant Examiner(s): BURNS, WILLIAM
• Application Number:
  US07/702,858
• Time in Patent Office: 337 Days
• Field of Search: 324/12.5, 324/158 P, 324/158 F, 269/71, 269/73, 33/1 M
• US Class Current: 324/750.22
• CPC Class Codes: G01R 1/07392 manipulating each probe element or tip individually
• CPC Class Codes: G01R 31/2806 Apparatus therefor, e.g. test stations, drivers, analysers, conveyors G01R31/2805, G01R31/281, G01R31/2818 take precedence

Abstract

An improved printed circuit board inspection apparatus in which its inspection probes are made to contact with a selected part or printed circuit section on a printed circuit board for making an inspection on the selected part or printed circuit section in terms of their performances or functions. The printed circuit board inspection apparatus uses two guide sets each having at least one pair of inspection probes and driving means to drive said inspection probes in X- and Y-directions to selected coordinate positions in the printed circuit board. A central processing unit controls said driving means so that the inspection probes of one guide set are used to make an inspection at a selected coordinated position while the other inspection probes are traveling to another selected coordinate position for subsequent inspection according to a predetermined program.

Claims

1. Printed circuit board inspection apparatus comprising:

mounting means to fix a printed circuit board at a predetermined position;

two or more guide sets each composed of a pair of upper and lower crossbar assemblies, each crossbar assembly having an arm suspending from the crossbar assembly and equipped with at least one inspection probe at its end, and driving means to drive the crossbar assembly in an X-direction above said printed circuit board, and to drive said arm in a Y-direction perpendicular to said X-direction and raise or lower associated probe; and

a central processing unit to command said driving means to bring selected inspection probes to selected positions above said printed circuit board and to lower such inspection probes until they come to contact the terminals of selected discrete circuit elements or printed circuit for detecting short-circuits or disconnections if any, in said printed circuit board, or for determining the kind or function each of said selected discrete circuit elements,

whereby the inspection probes of one guide set are making an inspection on a selected circuit element or printed circuit while the inspection probes of the other guide set are running to another selected position in which another inspection is to be performed under the control of said central processing unit.

2. Printed circuit board inspection apparatus claimed in claim 1, wherein each arm comprises a metal piece slidably mounted to an associated crossbar assembly, a mount plate fixed to said metal piece, a pair of probe heads vertically movably fixed to said mount plate, and drive means to raise or lower said prove heads, said inspection probes being fixed to said pair of probe heads.

3. Printed circuit board inspection apparatus claimed in claim 2, wherein said drive means to raise or lower said probe heads comprises a stepping motor, a rotatable link plate connected to a shaft of said stepping motor at the center of the rotatable link plate, and having two pins projecting from the opposite ends of the rotatable link and slidably fitted in lateral slots made in the upper ends of said probe heads, whereby when said stepping motor rotates said rotatable link plate to move said pins along a circular path in opposite directions while remaining in said lateral slots, one probe head is raised while the other probe head is lowered.

4. Printed circuit board inspection apparatus claimed in claim 3, wherein said pair of probe heads are fixed to said mount plate so as to converge and cross in their phantom extensions at a predetermined point in same plane.

5. Printed circuit board inspection apparatus claimed in claim 4, wherein said pair of probe heads have inspection probes of same kind.

6. Printed circuit board inspection apparatus claimed in claim 4, wherein said pair of probe heads have inspection probes of different kinds.