Abstract: An eccentric offset Kelvin probe with a beveled contact tip radially offset from the longitudinal axis of the probe which provides a reduced tip spacing between adjacent pairs of probes.

Abstract: A contact spring probe includes a plunger and a spring with a pair of opposed closed coils separated by an open coil. The plunger is secured at one end to one set of closed coils with a shoulder, flange or barb extending from the body of the plunger.

Abstract: A contact probe including a length of wire with head, coil and tail sections. The head and tail sections may be lengthened and offset from the longitudinal axis of the coil section to allow the probes to be densely packed in a substrate material. Two probes may be interleaved to provide improved electrical performance of the probe.

Abstract: A spring probe having a barrel, plunger and a back-drilled aperture is provided in which the centerline axis of the aperture is separate from the longitudinal axis of the plunger. A portion of the spring force directed along the longitudinal axis of the probe is transferred to a side force to bias the plunger against the barrel for electrical contact. The lighter, more uniform biasing and slight rotation/agitation of the plunger within that barrel increases the probe life and electrical performance.

Abstract: An electrical contact interface consists of a probe formed by a pair of oppositely extending plungers each having a contact tip, an inner shoulder and a rearwardly extending shaft terminating in a lug end. A coil spring is sleeved about the opposed plungers and is positioned between the opposite inner shoulders with the shafts extending toward each other and in constant sliding engagement with each other through the lug ends. The lug ends abut each other at an extreme travel relation of the plungers and prevent mutual disengagement of the plungers from within the coil spring. The probe is mounted in a fixture or other intermediate structure for positioning between circuit contacts. The probe finds particular use in applications requiring robust design and in which electrical contact must be maintained.

Abstract: An electrical contact test probe for use in providing electrical continuity between diagnostic equipment and a test point of an electrical circuit under test is provided. The test probe includes an elongated plunger slidably mounted within an elongated tubular barrel and extending outwardly therefrom for contacting the test point of the circuit under test. A spring is seated in the barrel and is interposed between the barrel and the plunger for biasing the plunger axially and outwardly of the barrel. The barrel consists of an elongated body having an inner bore, a generally closed end, and an open end. The barrel also has at least one cantilevered tab struck from the body and having a free end projecting into the inner bore toward the generally closed end of the barrel. The tab is located on the barrel such that the free end engages a shoulder of the plunger when the plunger is in an extended position so as to prevent outward biasing of the plunger beyond the extended position.

Abstract: A quick-connect terminal and receptacle for electrical spring test probes used in the printed circuit testing industry has a tubular receptacle having an inner bore with an entrance for inserting a wire terminal. The terminal has an open end receiving a base end of a wire. A barb cut from the terminal wall extends angularly into the terminal bore and away from the open end. The barb has an edge for gripping the wire end and preventing easy pullout. The wire extends to circuit testers which execute a testing routine upon the printed circuit board. The receptacles contain removable and replaceable spring probes and the quick-connect terminal and receptacle assembly provides speed and ease of probe replacement. Sealing rings can extend between the terminal and receptacle to maintain vacuum for use of the arrangement in vacuum actuated test fixtures.

Abstract: A switch probe, generally for use in testing cable harnesses, is for placement within a standard probe receptacle and can be removed and replaced as necessary. The switch probe includes a conductive barrel with a front open end and a rear closed end. A conductive first switch portion is received within the barrel at the rear closed end and includes a first shaft projecting forwardly. A conductive second switch portion is received within the barrel and has an engagement tip positioned forwardly of the barrel open end for electrical contact with a test site. A second shaft extends rearwardly and into axially spaced relation to the first shaft. An elongate hollow insulator extends fully between and provides a guideway for reciprocatory contact between the first and second shafts and fully shields the second shaft from electrical leakage prior to conductive contact of the second shaft with the first shaft.

Abstract: A module attachment for testing a linear high density array of test sites on a printed circuit board having such circuit test sites where an integrated circuit chip (IC) is to be mounted. Present IC's may have wire lead spacings as close as 0.010 inch with integrated chip development utilizing even more compact and close center pad spacing, such as 0.004 inch. This spacing is too close to use even the thinnest of spring contact probes. The module carries an array of densely packed thin wires embedded in a small matrix block mounted on spaced supports, which may be conventional, large diameter spring contact probes. Electrical connection to the array of wires in the module is done by each wire being connected to a separate wire lead with the wires bundled and routed to a test computer. In its closest wire spacings, the module permits testing of the densest IC's and in wider spacings, provides a low cost alternative to spring contact probes.

Abstract: A shielded electrical contact spring probe assembly for testing electrical printed circuit boards includes an outer barrel having an open end and a remote end, an inner core of dielectric material coaxially mounted within the barrel, and an electrical contact spring probe reciprocally seated within an axial bore in the core. A shield surrounds the core between the barrel inner wall and the core and extends the full length of the barrel. A shielding plunger is located in a cylindrical space between the barrel and the shield. The probe assembly remote end is for connection of an electrical transmission line, or in an alternative embodiment, inserting a second electrical contact spring probe within the core. The configuration and material of the core and the shield enable the entire probe assembly to maintain a selected impedance.

Abstract: A spring contact twisting electrical contact spring probe for testing electrical printed circuit boards includes a barrel having a spring seating end and an open end, a compression spring seated in the closed end of the barrel, and a plunger inserted into the barrel. The plunger includes a tail section, connected to a twister section comprising a square rod twisted along its longitudinal axis, and a shaft or probe section that protrudes from the barrel and includes the probe tip. Four crimps in the barrel retain the plunger inside the barrel and interact with the helical crests on the twister section to cause the plunger to rotate along its longitudinal axis as it reciprocates within the barrel. The twister section is retained entirely within the barrel at all times. The rotating plunger tip has edges that scrape off contaminants or coatings on the test sites of the circuit boards to obtain a sufficient electrical connection.

Abstract: An electrically conductive joint between a conductor and a connector includes a metallic tube and a crimp in the tube to secure a conductor therein. The crimp has a V-shaped outer portion and a substantially V-shaped inner portion including converging walls and a truncated apex with the angle of the inner and outer V-shaped portions being substantially the same. The conductor is secured within the tube in a substantially gas impervious relationship for use in pneumatically operated probe carrying fixtures for testing printed circuit boards.

Abstract: Electrical contact probes for use in providing electrical contact between diagnostic equipment and an electrical device to be tested are provided. The probes disclosed herein are particularly suitable for use where contact sites are spaced relatively close together. A structure is disclosed, usable for a plurality of probe designs, including two-component and three-component contact probes, which enables the probes to be mounted by a variety of methods. Generally, the methods of mounting disclosed are enabled by the positioning of a mounting flare on the contact probes. Also shown is a three-component contact probe design that is particularly suited for use in long stroke applications, wherein the contact probe generally comprises an outer cylinder member, an internally received barrel, and a movable probe member. This latter member includes a relatively narrow shaft portion which slidably engages the barrel member, within the cylinder member.