US 4,618,131 AGranted

PC board hold down system

AssigneeZenith Electronics Corporation

InventorsCarl Campisi, Brian D. Kay

Life of this patent

Estimating the term…

Loading patent…

Abstract

A hold down system for use with a generally planar printed circuit (PC) board includes at least one clamp which engages the circuit board and securely maintains it flat upon a circuit board transport mechanism to facilitate the insertion of electronic components upon the board by automatic positioning and insertion apparatus. The movable hold down clamp includes an elongated, generally vertically oriented housing which is positioned beneath the PC board and transport mechanism and is displaced upward above the PC board for engaging the board and pulling it downward upon the transport mechanism as the PC boards are displaced therealong. With an upper portion of the clamp extending above the circuit board either along an edge thereof or through an aperture therein, a pneumatically actuated hold down arm is extended laterally from the housing above the PC board and is displaced downward so as to engage the board's upper surface and pull the board downward and in tight-fitting engagement with the supporting transport mechanism. The PC board is thus securely maintained in a flat configuration and a fixed orientation and position during component insertion, testing, etc. Following component insertion on the PC board, the hold down arm is retracted, releasing the circuit board and the clamp is displaced downward allowing the transport mechanism to position another PC board above the hold down clamp whereupon the hold down procedure is repeated.

Claims10

Dependent claims

For use in the assembly of a PC board positioned upon and displaced by a transport mechanism as electronic components are positioned upon the PC board in predetermined locations on a first side thereof, clamp means for engaging and maintaining the PC board securely in position in a flat configuration upon the transport mechanism comprising:

a housing positioned on a second side of the PC board in a first retracted position, said housing including a linear slot aligned along the length thereof;
displacement means coupled to said housing for moving said housing between the first retracted position and a second extended position wherein said housing is positioned immediately adjacent to the PC board and extends to the first side thereof;
an arm positioned within the slot in said housing and movable along a first axis therein between a first retracted configuration and a second extended configuration in said housing, said arm including a distal hook portion recessed within said slot when said arm is in the first retracted configuration and extending outward from said slot when said arm is in the second extended configuration;
and
actuation means coupled to said arm for displacing said arm to said second extended configuration when said housing is in said second extended position whereupon the distal hook portion of said arm engages the PC board on the first side thereof and pulls the PC board tightly against the transport mechanism in securely maintaining the PC board in a flat configuration during the positioning of components thereon and for displacing said arm to said first retracted configuration following the positioning of components on the PC board, whereupon the distal hook portion of said arm disengages the PC board and said displacement means moves the housing to said first retracted position to permit the transport mechanism to displace the PC board from said clamp means.

2 more elements

Dependencies are inferred from the claim text.