Abstract: The invention relates to a contacting unit for a test apparatus for testing printed circuit boards. The contacting unit comprises a full grid cassette and an adapter. The full grid cassette is provided with a plurality of spring contact pins arranged in the grid of contact points of a basic grid of a test apparatus. The adapter is provided with test needles for electrically connecting each of the spring contact pins of the full grid cassette to a circuit board test point of a printed circuit board to be tested, the spring contact pins being secured in the full grid cassette against falling out on the side remote from the adapter and the test needles being secured in the adapter on the side remote from the full grid cassette. The adapter and the full grid cassette are releasably joined to each other. In this way, both the spring contact pins and the test needles are secured against falling out of the contacting unit in the assembled state of the adapter and the full grid cassette.

Abstract: A print head assembly (119) for printing a print medium (PM) onto a workpiece (W) through a printing screen (105) which includes a screen element having a pattern of printing apertures therein, the assembly comprising: first and second carriages (141) which are in use movably supported on respective ones of first and second guides (117); and first and second print head units (143, 145) which are mounted in adjacent, parallel relation to and between the carriages, wherein the print head units each comprise first and second print head actuators which are mounted on respective ones of the carriages, and a support member (151) which extends between the print head actuators, such as to be movable vertically thereby, and in use supports a printing element.

Abstract: The invention relates to a full grid cassette for a parallel tester for testing a non-componented printed circuit board, to a spring contact pin for such a full grid cassette and to an adapter for a parallel tester for testing a non-componented printed circuit board.

Abstract: A device and method of determining the electrical properties of an electrical device, including taking of at least one measurement of an electrical measured quantity at one or more brought-out electrical connections of each of several equipotential bodies of the electrical device, wherein measurement of the electrical measured quantity of certain equipotential bodies on at least one other brought-out electrical connection of the equipotential body concerned is not performed if a defect, which if appropriate is to be detected, of the relevant equipotential body in the area of this other connection, influences the electrical measured quantity more strongly than a tolerance of the measurement of this measured quantity.

Abstract: A workpiece carrier for supporting a plurality of workpieces, the workpiece carrier comprising a supporting body including a plurality of workpiece support elements, each for supporting a workpiece and providing for individual positioning of the same, the workpiece support elements each including at least one biasing element for applying a biasing force to an edge of the respective workpiece, at least one first cam for acting on an edge of the respective workpiece at a first location against the bias of the at least one biasing element, and at least one second cam for acting on an edge of the respective workpiece at a second location against the bias of the at least one biasing element, wherein the at least one first cam and the at least one second cam are operable such as to enable the position of the respective workpiece to be set relative to the supporting body.

Abstract: The invention relates to a method for the testing of circuit boards using a testing apparatus which has a test set-up for contacting the circuit board test points of a circuit board to be tested. The test set-up has test contact elements in a predetermined regular grid.

Abstract: The invention relates to a module for a parallel tester for the testing of circuit boards, and to a parallel tester comprising such modules. The modules have circuit boards standing at right-angles to the plane of the basic grid of the parallel tester, and on which contact pins are arranged along one side edge. The contact pins lie with their peripheral surfaces on flat sides of the circuit boards and protrude a short distance beyond the side edge of the circuit board. They are connected electrically and physically to contact fields formed on the circuit board. This arrangement of the contact pins is cost-effective to produce, mechanically stable, and permits the production of modules with a high density of contact pins.