JPS60127466A - Probe contact - Google Patents

Abstract

PURPOSE:To obtain the good contact with a measuring surface by breaking through the paste, flux or oxide film on the measuring surface, by providing a spiral part for rotating a contact element main body when said main body is adapted to the measuring surface. CONSTITUTION:The titled probe contact is constituted of a contact element main body 2 and a pipe shaped barrel part 3 for holding a part of said main body 2 in a freely slidable manner. The main body 2 has a spiral part, wherein at least a part of the main body 2 is formed into a spiral configuration, so as to impart rotary force to the main body 2 when the main body 2 is pressed to the measuring surface of a printed circuit board. Therefore, the good contact with the measuring surface can be obtained by breaking through the paste, flux or oxide film on the measuring surface.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a probe contact for testing a printed wiring board for checking the conductivity of a circuit on a printed wiring board.

The probe contacts used in printed circuit board circuit continuity tests directly contact the measurement surface of the printed circuit board to obtain measurement data, ensuring good contact between the contact surface and the probe contact. Otherwise, satisfactory test results will not be obtained. In particular, I
When attempting to check the continuity of the circuit by pressing a probe contact against the raised part caused by soldering when installing a C1 resistor, capacitor, etc. by soldering, be careful not to leave paste, flux, or oxide film on the raised part. Even if a probe contact is pressed against such a portion, the probe contact will not be able to break through the oxide film, etc., and there is a risk that reliable contact will not be ensured. In addition, in print evaporation, there are many areas where oxide films are formed, not just the raised areas due to soldering, and good test results cannot be obtained even if probe contacts are applied to such areas. .

The present invention has been developed in view of the above points, and even if an oxide film is formed on the measurement surface of a printed circuit board, for example, on a protruding part due to soldering, it can be penetrated to ensure reliable contact with the measurement surface. An object of the present invention is to provide a probe contact for inspecting a printed circuit board that can ensure contact.

Next, preferred specific examples of the present invention will be explained based on the drawings.

In the figure, a probe contact 1 of the present invention includes a contact body 2, a cylindrical IQ tube-shaped body 3 that slidably holds the contact body 2 inside, and a body 3 provided inside the body 3. The contact body 2 and the body 3 are made of a conductive material. The contact body 2 has a tip portion 5 and a portion 3
The sliding part 6 that is fitted into the inside of the , and the tip part 5 and the sliding part 6
and an intermediate portion 7 that connects the two. The tip 5 has a tip 8 that comes into contact with the measurement surface of the printed circuit board, and the tip 8 has a tip 8 that is arranged so that good contact can be made depending on the condition of the measurement surface.
It can be formed not only in the conical shape shown, but also in any other desired shape.

The intermediate portion 7 is integrally formed with the tip portion 5 and a sliding portion 6, which will be described later, and is located between the tip portion 5 and the sliding portion 6 to connect them. The intermediate portion 7 has an elongated flat rod-like shape and is twisted spirally in a fixed direction over its entire length in the longitudinal direction, thereby forming a spiral portion of the contact body 2 . The axis of the spiral around which the intermediate portion 7 is twisted is formed to coincide with the axes of the other portions of the contact body 2, that is, the tip portion 5 and the sliding portion 6. Here, the intermediate portion 7 is not limited to a flat rod shape, but may have a triangular or quadrangular cross section, and the torsion angle thereof is preferably at least 45°, but may be set as appropriate. A flat constriction 9 is provided at the front end portion of the body portion 3 into which the contact body 2 is inserted, and the constriction 9 is an elongated flat bar-shaped intermediate portion 7f: the cross section is flat so that it can be inserted and removed smoothly. It is formed. The sliding portion 6 of the contact body 2 is formed into a circular cross section with a diameter approximately corresponding to the inner diameter of the cylindrical body 3 so that it can be smoothly fitted into the interior of the cylindrical body 3. As a result, the sliding part 6 can slide inside the body part 3 in the longitudinal direction of the body part 3, but due to the presence of the constriction 9, it is prevented from coming out from the body part 9, and the sliding part 6 is prevented from coming out from the body part 9. 3. A protrusion 11 is provided at the end 10 of the sliding portion 6 opposite to the side connected to the intermediate portion 7, and a folded portion 13 is provided at the end 12 of the trunk 3 opposite to the constriction 9. is formed, and the protrusion of the folded part 13 and the sliding part 6]1
A coil spring 4 is disposed between the ends 1O on the side, and the coil spring 4 always presses the contact main body 2 in the direction of the tip 5, and the middle part 7 of the sliding part 6 The side end 14 rests against the constriction 9. Coil spring 4F due to the protrusion 11! , placed in the appropriate position. An opening 15 is provided at the end portion 12 of the body portion 3 where the fold 13 is formed.

(Left below) When using the Zoroshi contact 1 configured as described above, the probe contact 1 passes through the mounting plate 16, which is referred to as the test head of a printed circuit board inspection machine, and forms a molten layer on the mounting plate 16. Alternatively, the body part 3 is fitted into the socket 17 which is attached with an adhesive, and the body part 3 is mounted on a printed circuit board inspection machine. The socket 17 is made of a conductive material and has a terminal 18, to which a lead wire is connected by soldering or the like. As shown in FIG. 3, the probe contact l fitted into the socket 17 and fixed to the mounting plate 16 of the printed circuit board inspection machine is 1. C. Electronic or electrical components such as resistors 20
The printed circuit board 21 is attached by soldering.
When applied to the contact probe 1, the tip 8 of the contact probe 1 abuts against the soldered raised portion 22. At this time, since the probe contact 1 is pressed against the printed circuit board 21 with a pressure above a certain level, the sliding part 6 of the contact body 2 is pushed into the body part 3, and the coil no.
contracts. Therefore, the tip 8 of the contact body 2 presses the raised portion 22 with a force greater than a certain level, and this pressing force acts on the contact body 2 as a reaction.

The force applied to the contact body 2 due to the reaction is:
The force acting in the axial direction of the contact body 2 is applied to the intermediate portion 7 which is twisted in a spiral shape and forms a spiral portion. changes into a force in the spirally twisted direction as described above. As a result, a rotational force is applied to the contact body 2.

That is, when the contact main body 2 of the probe contact 1 comes into contact with the printed circuit board 21 with a force above a certain level, the tip 8 rotates in the direction B by an amount corresponding to the force, thereby causing the raised portion 22 to rotate. The tip 8 and the raised portion 22 reliably break through the covering paste, flux, and oxide film.
to ensure good contact with the In addition, with conventional probe contacts, it was impossible to break through the oxide film, slack, etc. on the measurement surface and obtain good contact unless a fairly strong spring was installed inside the body. Since the probe contact of the present invention is configured so that the tip that contacts the measurement surface rotates when it is pressed against the measurement surface of the printed circuit board, it is not necessary to install a very strong spring inside the body that holds the contact body. It does not need to be installed and can easily break through the oxide film on the surface. Also, by using a strong spring, the risk of damaging the printed circuit board can be prevented.

In addition, the spiral portion for rotating the contactor main body 2 is formed by the force ζ, which is formed by the intermediate portion 7 in the form of a long and thin flat bar twisted spirally in the above-mentioned specific example. However, the intermediate portion 7 may be formed into a round bar shape, the spiral portion may be configured as a spiral groove carved on the surface of the round bar, and a protrusion that engages with this groove may be provided inside the body portion 3. It's okay.

Further, a spiral groove is formed on the inner surface of the body part 3 to thereby constitute a spiral part, and a protrusion that engages with the groove formed on the inside of the body part 3 is provided on the contact body 2. The purpose can also be sufficiently achieved by providing the following.

As mentioned above, the probe contact of the present invention has a spiral portion that rotates the contact body when applied to the measurement surface of a printed circuit board, so that the paste, 7lux and Good contact with the measurement surface can be obtained by breaking through oxide films, etc.

[Brief explanation of drawings]

FIG. 1 is an explanatory longitudinal cross-sectional view of the probe contact of the present invention installed in a printed circuit board inspection machine, and FIG. 2 is a cross-sectional view taken along the JL-II line of the probe contact shown in FIG.
FIG. 3 is an explanatory diagram showing a state in which the probe contact shown in FIG. 1 is applied to a printed circuit board. 1... Probe contact, 2... Contact body, 3
... body part, 4 ... coil spring, butt part ... tip part, 6 ... sliding part, 7 ... middle part, 8 ... tip, 9 ... constriction. f day lii person l ``Rishima Mura 几

Claims (1)

[Scope of Claims] fil Consists of a contact body and a rib-shaped body that slidably holds a part of the contact body inside, and the contact body is pressed against the measurement surface of the printed circuit board. In some cases, a probe contact is used in which the contact body has a spiral portion in which at least a portion of the contact body is formed in a spiral shape in order to apply a rotational force to the contact body. The tip part, the sliding part that is slidably held inside the body part, and the middle part that is between the tip part and the sliding part and connects them, and the spiral part is the middle part. The probe contact according to claim 1, which is formed in the following: (3) an elongated flat rod-shaped helical portion formed by twisting the intermediate portion in a spiral manner over the entire length in the longitudinal direction of the intermediate portion; The probe contact according to claim 2, comprising: (4) an intermediate portion formed of a round bar, and a spiral portion formed on the round bar to engage with a protrusion provided inside the body portion; (5) The body has a constriction at one end, and the constriction is formed by an elongated flat bar-shaped spiral portion. The probe contact according to claim 3, wherein the probe contact is formed to have a flat cross section so that the intermediate portion of the probe can be smoothly moved in and out. The body has a pipe-like body that freely holds the body, and the body has at least one part of the body that applies rotational force to the contact body when the contact body is pressed against the measurement surface of the printed circuit board.
A probe contact having a spiral portion. (7) The probe contact according to claim 6, wherein the spiral portion is a spiral groove formed inside the body so as to engage with a protrusion provided on the contact body.