Adaptable Multiport Test Fixture System
During the process of manufacturing an electric circuit or before placing the circuit in operation, the circuit usually is tested. Typically, the circuit is mounted in a custom fabricated test fixture with each different type circuit to be tested requiring its own custom fixture. Given the immense variety of electrical circuits, fixture fabrication is time consuming and expensive.
The present invention is a fixture used to support electrical circuits for testing. It is particularly useful for physically and electrically mounting circuits which are edge accessed.
The fixture uses a base plate or matrix having a grid formed by T slots milled in the x and y planes or directions. Other elements of the fixture are provided with the same T slot(s) and/or T shaped projections. The T shaped projections are designed to cooperate with the T slots by sliding and, when the desired position is reached, locking within the T slots.
The x and y directions need not be perpendicular. The z direction is perpendicular to both the x and y directions.
Circuit supports extend perpendicular to the base in the z direction. Each circuit support is provided on its lower end with a T shaped projection or locking guide cooperating with a T slot on the base matrix grid. The circuit support slides in the T slot until the appropriate location is reached and is locked into place. The top surface of the of the circuit support directly supports the circuit and provides electrical contact while it is being tested.
The circuit supports also support the electrical connectors required to test the circuit. T shaped projections or locking guides located on an input/output (I/O) positioner and an electrical connector assembly cooperate with and lock into T slots on the circuit support and the I/O positioner respectively.
Although it is recommended that the test fixture be used with two circuit supports, each supporting the circuit and also supporting the appropriate electrical connector, several may be used depending on the size and shape of the circuit. The number of circuit supports used also depends on the number and type of circuit components and/or connectors as are present on the substrate. A circuit support need not be provided with an I/O positioner and a connector assembly but may be used in its circuit support role alone.
The test fixture is typically used in the testing of a circuit comprising circuit components on a substrate. Microwave, analog and digital electronic circuits are examples of the circuit types that may be tested in the fixture. It may be used to test multiport circuits having a variety of transmission line feed/launch types and electrical connector types such as subminiature type A (SMA), coaxial and bias connectors. Probe card like electrical contacts can also be accommodated. Closely spaced circuit components and especially microwave parts can be easily accessed.
Patent Status: U.S. patent(s) 5,153,505 issued.CONTACT:
Mr. M. T. Hickman