JP2011137791A - Probe pin for large current - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a probe pin for a large current having small electric resistance and a wide application range. <P>SOLUTION: This probe pin includes: an abutting member 14 having a plurality of contact parts 14a for electric conduction formed and arranged dispersedly thereon; a plunger 11 (advancing/retreating member) comprising a rod-shaped conductor, wherein the abutting member 14 is mounted on the head 11a, and a wire end 18 is connected to the tail 11b; and a coil spring 12 (energizing means) for energizing the plunger 11 so that the abutting member 14 abuts on a specimen. A peripheral part of the abutting member 14 is branched radially to form the contact parts 14a, and a center part of the abutting member 14 is fixed to the plunger 11 by a fastener 15 inserted into a fastener insertion hole 14b in a hollow 11c, and the contact parts 14a are extended to the furthermore outer peripheral side than the inner peripheral edge (11d) of the hollow 11c. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a probe pin for large current for energizing with the tip of a probe head in contact with a subject, and more particularly to a probe pin for large current that makes contact at multiple points for energization of a large current.

The high current probe pin is made of a conductive pin, and is held by a support member one by one and establishes an electrical connection by bringing the tip into contact with the subject.
In addition, in order to stabilize the contact pressure, a rod-like advance / retreat member made of a conductive member is urged toward the subject by a coil spring or the like, and undesired contact welding due to uneven distribution of the contact portion is prevented. In addition, the number of contact portions and the number of contact portions are increased (for example, see Patent Documents 1 and 2).
Furthermore, in order to improve the durability, a contact member made of a hard tungsten alloy or the like is also attached to the distal end portion of the advance / retreat member.

  Such a probe pin for large current will be specifically described with reference to the drawings so as to help explain the present invention. 6A is a front view of a conventional high current probe pin 60, FIG. 6B is a front view of a contact member 61 of a head 11a (tip portion) of a plunger 11 (advance / retreat member) of the probe pin 60, (C) is a plan view of the contact member 61, (d) is a front view partially showing a state in which the probe is completed after being attached to the support member 16 and connected to the end of the electric wire, (e). Is a front view of the measurement state.

  The probe pin 60 (see FIG. 6A) is made of a metal and conductive plunger 11 (advancing / retracting member) such as brass, a coil spring 12 (biasing member) into which the plunger 11 can be loosely inserted, and the plunger 11 inserted therethrough. A cylindrical sleeve 13 (cylindrical guide member) that can be formed, the plunger 11 is formed in an elongated round bar shape, and the sleeve 13 is fitted to the plunger 11 so as to be slidable and axially movable. Thus, when the coil spring 12 pushes the front end of the sleeve 13 away from the head 11a (tip portion) of the plunger 11, the plunger 11 is urged forward. The rear end portion of the plunger 11 protrudes from the sleeve 13 so that the end portion of the electric wire can be connected.

Further, an abutting member 61 made of a different material different from the plunger 11 is attached to the leading edge of the head 11a (the tip of the advance / retreat member) in order to enhance durability.
The contact member 61 (see FIGS. 6B and 6C) is made of a tungsten disk having excellent wear resistance, and the upper surface of the contact member 61 is formed by engraving a groove 61b having a V-shaped cross section. A plurality of contact portions 61a of pyramidal protrusions are formed in a shape, that is, vertically and horizontally at equal pitches. Then, the lower surface side of the contact member 61 is brazed to the front end surface of the head 11 a with a silver bar 62, and the contact member 61 is fixed to the most distal end of the plunger 11.

Such a probe pin 60 (see FIG. 6D) is held by the support member 16 by press-fitting the sleeve 13 into the through hole of the support member 16, and the wire end is connected to the rear end of the plunger 11. This completes preparation for use as a probe.
During use (see FIG. 6E), the contact member 61 of the head 11a of the plunger 11 and the surface of the subject 20 are brought into contact with each other, and further pressed down to stabilize the contact pressure by the elastic force of the coil spring 12. This stabilizes the electrical conduction state of the contact portion.

Japanese Utility Model Publication No. 62-114366 Japanese Utility Model Publication No. 63-105881

Thus, in the conventional high current probe pin, the contact member for multi-point dispersion contact attached to the tip of the advance / retreat member is made of tungsten or the like. High-hardness members and cemented carbide members such as tungsten and tungsten alloys are not only durable and long-lasting, but also have an electrically conductive state due to the protruding contact portions breaking through the dirt and oxide film on the surface of the specimen. It also has the advantage of contributing to establishment.
However, such a hard member generally has a dissatisfaction that processing cost increases and electric resistance is large.

  Furthermore, in the case of a high-hardness member or a cemented carbide member, the property of being hard, which was an advantage for establishing electrical conduction, causes a drawback that the scope of application is narrow because the subject is limited from the viewpoint of being difficult to deform. In other words, if the surface of the subject is not completely flat and there are irregularities or undulations in the probe pin contact portion on the subject surface, the tip of the probe pin advancing / retreating member, even if it is slight Since the contact state between a large number of contact portions dispersed in the contact member and the surface of the subject becomes uneven, the multi-point dispersed contact is partially lost, and the electrical conduction state is difficult to stabilize. The application to the subject whose probe pin contact portion is sufficiently flat is limited.

  Therefore, by devising the shape of the contact member for multi-point dispersed contact, etc., and improving so that the multi-point dispersed contact can be aligned and stabilized by using conductive members and good conductors with low electrical resistance, the electrical resistance can be reduced. Realizing a probe pin for large current that is small and has a wide application range is a technical problem. Moreover, it becomes a further subject to be able to provide such a high-current probe pin at low cost.

  The probe pin for large current of the present invention (Solution 1) was created to solve such a problem, and a contact member in which a plurality of contact portions for electrical conduction are formed and distributed. And an advancing / retreating member made of a rod-shaped conductor, with the abutting member attached to the front end and an electric wire connected to the rear end, and the advancing / retreating member to abut the subject against the abutting member. In a high-current probe pin having an urging means for urging, a peripheral edge portion of the abutting member diverges radially to form the contact portion, and a recess is formed on a distal end surface of the advance / retreat member. A center portion of the contact member is fixed to the advance / retreat member in the recess, and the contact portion of the contact member extends from the inner periphery of the recess to the outer peripheral side. It is characterized by that.

  The probe pin for large current according to the present invention (solution means 2) is the probe pin for large current of the solution means 1, wherein the abutting member is made of a single piece formed by punching a plate. And

  Further, the high current probe pin of the present invention (Solution means 3) is the high current probe pin of the above solution means 1 and 2, wherein a fastener insertion hole is formed through the central portion of the contact member. The contact member is fixed to the advance / retreat member by a fastener inserted into the fastener insertion hole.

  The probe pin for large current of the present invention (solution means 4) is the probe pin for large current of the solution means 1 to 3, wherein the contact portion of the contact member is not in contact with the subject. In the state, it floats away from the inner periphery of the dent.

  In such a high-current probe pin of the present invention (Solution 1), the peripheral portion of the abutting member is radially branched to maintain a large number of contact portions and maintain a dispersed arrangement, and a large number of contacts. The abutting members are integrated by connecting the parts while being cantilevered at the center. In addition, the central part of the contact member plays a necessary fixing role while being housed in a recess on the front end surface of the advancing / retreating member so that it does not get in the way, and the contact part of the contact member comes out of the recess and from the inner peripheral edge of the recess By extending to the outer peripheral side, when the contact portion of the contact member contacts the subject, it swings like a seesaw with the inner peripheral edge of the recess as a supporting point.

  And at the time of swinging, since the variation of the contact pressure is mitigated by the deformation of the portion near the center of the contact portion of the contact member, even if there is some unevenness or undulation in the probe pin contact portion on the subject surface, The contact state between the contact member and the surface of the subject is stabilized for a large number of contact portions. In addition, the contact portions are pressed against each other by the straight movement, so that the electrical conduction state is not only established, but the contact portions are rubbed by the swinging to further enhance the establishment of the electrical conduction state. In addition, the establishment of an electrically conductive state by rubbing does not require a stronger force or higher hardness than when pushing. For this reason, materials that can be selected for the contact member are widened, so that a member having a smaller electric resistance than before can be used. Therefore, according to the present invention, it is possible to realize a high-current probe pin having a small electric resistance and a wide application range.

  Further, in the probe pin for high current of the present invention (Solution means 2), the contact member is integrally formed by punching the plate body by utilizing the fact that the hardness of the contact member can be lowered. By doing so, it is possible to provide a probe pin for large current with low electrical resistance and wide application range at low cost.

  Furthermore, in the probe pin for large current of the present invention (Solution means 3), the contact member is fixed to the advance / retreat member by inserting the fastener into the fastener insertion hole at the center of the contact member. As a result, the abutment member mounting operation and replacement operation can be performed easily and quickly.

  Further, in the probe pin for large current of the present invention (Solution means 4), the contact portion of the abutting member floats away from the inner peripheral edge of the recess in the free state so that the individual contact portions can be moved. Since the distance is increased by the flying height, the function of reducing the fluctuation of the contact pressure is enhanced.

About Example 1 of this invention, the structure of the probe pin for large currents is shown, (a) is a front view of a probe pin, (b) is the longitudinal cross-sectional view, (c) is a top view of the tip part of an advancing / retreating member, (D) is a longitudinal front view thereof, (e) is a plan view of the abutting member, (f) is a longitudinal front view thereof, and (g) is a front view in partial cross section of the probe which has been supported and connected. is there. (A) is a front view at the start of contact between the probe pin and the subject, (b) is an enlarged longitudinal sectional view of the contact portion at that time, and (c) is a view after the contact between the probe pin and the subject is established. Front view, (d) is an enlarged longitudinal sectional view of the contact portion and the surroundings at that time. About Example 2 of this invention, the structure of the probe pin for large current is shown, (a) is a front view of a probe pin, (b) is a vertical front view of the front-end | tip part of an advancing / retreating member. (A) is the front view of the partial cross section view which concerns on the probe which also completed support and connection, (b) is the front view after contact | abutting establishment with a probe pin and a test object. About Example 3 of this invention, (a) and (b) are both front views, such as a probe pin. The conventional high current probe pin is shown, (a) is a front view of the probe pin, (b) is a front view of the abutting member at the tip of the advancing and retracting member, (c) is a plan view of the abutting member, d) is a front view in partial cross-section of the probe that has been supported and connected, and (e) is a front view in a measurement state.

About the probe pin for such a large current of this invention, the specific form for implementing this is demonstrated by the following Examples 1-3.
The embodiment 1 shown in FIGS. 1 and 2 embodies the above-described solving means 1 to 3 (claims 1 to 3 as originally filed), and the embodiment 2 shown in FIGS. The solution 4 (claim 4 at the beginning of the application) is embodied, and the third embodiment shown in FIG. 5 is a modification thereof. In the drawings, the same reference numerals are given to the same constituent elements as those in the prior art. In addition, what is described in the background art section is also common to the following embodiments.

  A specific configuration of the high current probe pin according to the first embodiment of the present invention will be described with reference to the drawings. 1A is a front view of a probe pin 10 for large current, FIG. 1B is a longitudinal sectional view of the probe pin 10, and FIG. 1C is a head 11 a (tip) of a plunger 11 (advance / retreat member) of the probe pin 10. (D) is a longitudinal front view thereof, (e) is a plan view of the contact member 14, (f) is a longitudinal front view thereof, and (g) is an attachment to the support member 16 and an end portion of the electric wire. It is the front view which showed the state which complete | finished the connection of 18 and became a probe in the partial cross section.

  The probe pin 10 (see FIGS. 1A and 1B) is made of a rod-shaped conductor, and a contact member is attached to the tip, and a plunger 11 as an advancing / retracting member that can connect an electric wire to the rear end. A coil spring 12 as an urging means for urging the plunger 11 so as to bring the abutting member into contact with the subject 20, and a cylindrical guide member that is fitted on the plunger 11 and restricts its advancement and retraction in the axial direction. This is the same as the conventional probe pin 60 described above in that it is held by the support member 16 by press-fitting the sleeve 13 into the through hole of the support member 16. . The point that the contact member at the front end of the plunger 11 is brought into contact with the subject 20 to establish electrical continuity between the subject 20 and the connecting wire at the rear end of the plunger 11 is the same as in the prior art.

  On the other hand (see FIGS. 1A to 1G), a female thread is formed on the tail 11b (rear end) of the plunger 11, and the wire end 18 is fixed and connected thereto with a nut 17. (See FIG. 1 (g)), and a point in which a recess 11c (sink) is formed on the distal end surface of the head 11a (tip portion) of the plunger 11 (advance / retreat member) (FIG. 1 (c)). , (D)), a point where a new contact member 14 is introduced in place of the contact member 61 (see FIGS. 1A to 1D), and the contact member 14 on the distal end surface of the plunger 11. The probe pin 10 is different from the probe pin 60 in that the attachment means is not a brazing but a fastener 15 (see FIGS. 1A to 1D).

  The contact member 14 inherits the basic requirements for large current from the contact member 61 in that a plurality of contact portions for electrical conduction are formed and distributed, but how to make a specific shape and material Is also different from the contact member 61. That is, the abutting member 14 is an integrated body made by punching a predetermined shape portion from a flat plate having a constant thickness with a press or the like and simultaneously bending it. For example, the contact member 14 is used in a high temperature environment of 200 ° C. or higher. Stainless steel is used as the material, and it is made of beryllium copper, etc., which has good conductivity and springiness if it is not so hot.

  The shape of the abutting member 14 (see FIGS. 1 (e) and (f)) is like a flower that opens as the petals move away, and its peripheral portion is cut out from the disk at several equal pitch angles and remains. The peripheral edge branches radially to form the contact portion 14a. The number of the contact portions 14a is six, but may be five or less, or may be seven or more as long as the same or similar shapes are dispersed radially at an equal pitch angle. The central portion of the abutting member 14 remains flat as a whole, and is a connecting portion that supports a large number of contact portions 14a in a cantilevered state slightly tilted. The insertion hole 14b is formed through. The fastener insertion hole 14b, the notch between the contact portions 14a, and the bending for inclining the contact portion 14a can be processed in a single pressing process.

  The front end surface of the head 11a of the plunger 11 (see FIGS. 1 (c) and (d)) is formed with a shallow round dish-shaped recess 11c in the center by engraving or the like. The peripheral part of one round which became like this remains. The diameter of the recess 11 c is smaller than the diameter of the circumscribed circle of the contact member 14. Moreover, the fastener insertion hole which inserts the fastener 15 is drilled in the center of the dent 11c. The fastener 15 has a thick head and a narrow neck lower part. The fastener 15 is attached to the fastener insertion hole after the lower neck is inserted into the fastener insertion hole 14b. And is fixed to the plunger 11.

A specific shape or the like of the fastener 15 may be one that is screwed into the fastener insertion hole as shown in the illustrated small bolt, or one that is driven into the fastener insertion hole as shown in the crimping pin (not shown). It may be of any other shape, but preferably the entire head is contained in the recess 11c so that the head does not protrude and obstruct the contact of the contact member 14 with the subject. The top portion is always located behind the contact portion 14a.
And by attaching using the fastener 15, the center part of the contact member 14 is fixed to the plunger 11 (advance / retreat member) in the recess 11c, and the contact part 14a of the contact member 14 is recessed 11c. It is also in a state extending from the inner peripheral edge (11d) of the recess 11c to the outer peripheral side.

  The use mode and operation of the high current probe pin 10 of the first embodiment will be described with reference to the drawings.

  FIG. 1G is a front view of the probe completed from the probe pin 10 after the attachment to the support member 16 and the connection of the wire end 18 are completed. 2 (a) and 2 (b) show a state when the probe pin 10 and the subject 20 start to contact, (a) is a front view, and (b) is the contact portions 14a and 21. It is a longitudinal cross-sectional enlarged view which concerns on the circumference | surroundings. 2 (c) and 2 (d) show a state after contact in which the probe pin 10 and the subject 20 are sufficiently pressed to establish connection, (c) is a front view, and (d) is a front view. It is a longitudinal cross-sectional enlarged view which concerns on the contact parts 14a and 21 and its circumference | surroundings.

  First, the probe pin 10 is held by the support member 16 by press-fitting a sleeve 13 (cylindrical guide member) into the through hole of the support member 16 (see FIG. 1G), and the tail of the plunger 11 (advance / retreat member). By connecting the wire end 18 to the 11b (rear end) with the nut 17, preparation for use as a probe is completed. In use (see FIG. 2), the contact member 14 of the head 11a (tip portion) of the plunger 11 is brought into contact with the surface of the subject 20 (see FIGS. 2 (a) and 2 (b)) and further pushed. Then, the contact pressure is stabilized by the elastic force of the coil spring 12 to stabilize the electrical conduction state of the contact portion 14a (see FIGS. 2C and 2D).

  As described above, the method of using the probe pin 10 is generally the same as in the prior art, but the contact operation of the contact portion 14a is different from the conventional one due to the difference in the shape of the contact member 14 and the like. That is, until the probe pin 10 comes into contact with the subject 20 (see FIGS. 2A and 2B), the contact portion 14a of the contact member 14 is located on the bank-like peripheral portion of the recess 11c of the head 11a of the plunger 11. The part located slightly above the center of the contact portion 14a is supported by the inner peripheral edge 11d (inner corner) of the recess 11c, and the center of the contact member 14 is fixed to the inner bottom of the recess 11c. Since the contact portion 14a and its base portion are not parallel to the distal end surface of the plunger 11 but slightly inclined, the contact portion 14a is also inclined with respect to the contact portion 21 on the surface of the subject 20. Contact with posture.

  Then, when the contact portion 14a of the contact member 14 contacts the contact portion 21 on the surface of the subject 20 and further presses to apply the biasing force of the coil spring 12, the head 11a of the plunger 11 and the surface of the subject 20 are applied. The contact portion 14a and its base portion swing like a seesaw with the inner peripheral edge 11d of the recess 11c as a supporting point. Along with the swing, a portion near the center of the contact portion 14a of the contact member 14 is bent, and a reaction force generated by the bending deformation is applied to the contact portion 14a of the contact member 14 and the contact portion 21 of the subject 20. The gap between the plunger 11 and the subject 20 is reduced until the contact pressure that acts is reached and the sum of the contact pressures related to the multiple contact portions 14 a and 21 is balanced with the urging force of the coil spring 12.

  As described above, when the contact member 14 and the subject 20 are in contact with each other, fluctuations in the overall contact pressure are alleviated by the biasing force of the coil spring 12, and at the same time, local contact at each of the contact portions 14a and 21 is achieved. Since fluctuations in contact pressure are alleviated by elastic bending deformation of the contact member 14 and its base, the contact portion 21 on the surface of the subject 20 which is the contact portion of the contact portion 14a of the contact member 14 of the probe pin 10 is used. However, even if there are some irregularities and undulations, the contact state between the contact portion 14a and the surface of the subject 20 is stable for a large number of contact portions 14a and 21.

  Further, the contact portions 14a and 21 are pushed by the linear motion component in the direction perpendicular to the surface of the subject 20 in the relative motion when the contact portion 14a of the contact member 14 is pushed into the surface of the subject 20. The electrical continuity between the probe pin 10 and the subject 20 is established by matching, as in the conventional case, but unlike the conventional case, the contact portion 14a of the contact member 14 swings, so the subject 20 In other words, there is a slight amount of frictional movement in the direction parallel to the surface of the surface, and the contact portions 14a and 21 rub against each other accordingly, so that the electrical conduction between the probe pin 10 and the subject 20 occurs. State establishment is further strengthened.

  A specific configuration of the high current probe pin according to the second embodiment of the present invention will be described with reference to the drawings. 3A is a front view of the probe pin 30 for large current, and FIG. 3B is a longitudinal front view of the head 11a (tip portion) of the plunger 11 (advance / retreat member).

  The high current probe pin 30 differs from the probe pin 10 of the first embodiment described above in that the sleeve 13 is omitted and a groove 11e that encircles the outer peripheral surface of the plunger 11 (advance / retreat member) is engraved. In the free state in which the contact point 14a of the contact member 14 is not in contact with the subject 20, the formed point is lifted from the inner peripheral edge 11d (supporting point) of the recess 11c (sitting) of the tip surface of the head 11a. It is a point away.

  The use mode and operation of the probe pin 30 of the second embodiment will be described with reference to the drawings. FIG. 4A is a front view partially showing a state where the probe has been supported and connected, and FIG. 4B is a front view after the contact between the probe pin 30 and the subject 20 is established. is there.

In this case (see FIG. 4A), the probe pin 30 is held by the support member 16 by inserting the retaining ring 32 into the groove 11 e of the plunger 11 after inserting the plunger 11 through the through hole of the support member 31. Then, the end of the electric wire is screwed to the rear end surface of the plunger 11 so that the preparation for use as a probe is completed.
When the probe pin 30 and the subject 20 come into contact with each other (see FIG. 4B), the plunger 11 moves in the axial direction while sliding in the through hole of the support member 31, thereby the coil spring 12. , The contact pressure is generated by the biasing force.

The operation of the contact member 14 is generally the same as described above, but the probe pin 30 and the subject are separated from each other in the free state where the contact portion 14a of the contact member 14 and the inner peripheral edge 11d of the head 11a are separated. Since the movable distance by which the individual contact portions 14a can be displaced when the contact portions 20a and 20 are in contact with each other is increased, the function of reducing fluctuations with respect to the contact pressure acting between the contact portions 14a and 21 is enhanced.
Further, since the probe pin 10 has no groove processing on the outer periphery of the plunger 11, the probe pin 10 can be easily formed in a narrow shape having a diameter of 5 mm or less, whereas the probe pin 30 has a groove processing on the outer periphery of the plunger 11 so that the diameter is 5 mm. Although only the above thick shape is easy to make, the cost of the probe pin 30 is reduced by omitting the sleeve 13.

FIG. 5A shows a front view in which a sleeve 33 (cylindrical guide member) is added to the above-described high current probe pin 30.
This is suitable when it is difficult or unsuitable to form the through hole for slidingly guiding the plunger 11 in the support member 31.

FIG. 5B shows a front view in which an air cylinder 34 is employed instead of the coil spring 12 as an urging member of the above-described high current probe pin 30.
When the air pressure is used, the pressing force becomes almost constant regardless of the displacement, which is suitable for an environment where the air pressure system can be used easily.

  The high current probe pin of the present invention can be used for electrical inspection and testing of semiconductor devices, printed wiring boards and other circuit boards.

10 ... probe pin, 11 ... plunger (advancing / retracting member),
11a: head (front end), 11b: tail (rear end),
11c ... dent (spotting), 11d ... inner peripheral edge (support point),
11e ... groove, 12 ... coil spring (biasing member),
13 ... Sleeve (cylindrical guide member), 14 ... Contact member,
14a ... contact portion, 14b ... fastener insertion hole, 15 ... fastener,
16 ... support member, 17 ... nut, 18 ... wire end,
20 ... Subject, 21 ... Contact part,
30 ... probe pin, 31 ... support member, 32 ... retaining ring,
33 ... Sleeve 33 (tubular guide member), 34 ... Air cylinder,
60 ... probe pin, 61 ... contact member,
61a ... contact portion, 61b ... engraved groove, 62 ... silver

Claims (4)

  A contact member in which a plurality of contact portions for electrical conduction are formed and distributed, and a rod-shaped conductor, and the contact member is attached to the front end, and the rear end can be connected to an electric wire. In a high-current probe pin comprising a member and a biasing means for biasing the advance / retreat member so that the contact member is brought into contact with a subject, the peripheral portion of the contact member diverges radially and A contact portion is formed, and a recess is formed in a front end surface of the advance / retreat member, and a central portion of the contact member is fixed to the advance / retreat member in the recess, and the contact of the contact member A high current probe pin, characterized in that a portion protrudes from the recess and extends from the inner peripheral edge of the recess to the outer peripheral side.   2. The probe pin for high current according to claim 1, wherein the abutting member is made of a single body formed by punching a plate.   A fastener insertion hole is formed through the central portion of the contact member, and the contact member is fixed to the advancing / retracting member with a fastener inserted into the fastener insertion hole. The high-current probe pin according to claim 1 or 2.   The large contact according to any one of claims 1 to 3, wherein the contact portion of the contact member floats away from the inner peripheral edge of the recess in a free state where the contact portion does not contact the subject. Probe pin for current.

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