It is well known in the art that circuit elements such as resistors or integrated circuits may be connected to a printed circuit board by inserting lead wires extending from such circuit elements in selected through holes of the printed circuit board and by soldering the lead wires to the circuit pattern on the boards. Recently developed surface mount technology enables circuit elements to be attached directly to circuits located on a surface of a printed circuit board.
Specifically, circuit elements are arranged with their lead wires located on selected portions of the circuit pattern of a printed circuit board, and solder is applied to the lead wires of circuit elements. The printed circuit board is then passed through an automated soldering apparatus which solders the circuit elements to selected portions of the circuit pattern. Usually a plurality of printed boards each bearing a plurality of circuit elements will be carried one after another into the automated soldering apparatus by conveyor belt.
Integrated circuits, resistors, capacitors and other circuit elements to be located on printed circuit boards are of relatively small size. Consequently, the inlet opening to the automated soldering apparatus is designed to be of a relatively low height.
Accordingly, there is a need to reduce the size of electrical connectors which are mounted on these boards. Connectors used in connecting printed circuit boards have increased in size with the increase in size of the printed circuit boards having circuit patterns of increased density. Such a board-to-board electrical connector is designed to be integrally connected to one board and accommodate the other board in the space defined by two guide posts integrally connected to the opposite sides of the connector housing. These guide posts must be tall enough to apply an adequate force and support to hold firmly a printed circuit board when it is inserted between the opposite guide posts.
Generally, these guide posts are of such height that they cannot pass through the automated soldering apparatus because the guide posts are too tall to pass through the inlet of the automated soldering apparatus.