JP6373009B2 - High current probe - Google Patents

Description

  The present invention relates to a probe for large current used for measuring resistance values, voltage values, and the like.

  2. Description of the Related Art Conventionally, an inspection probe has been provided in which an electrical connection is established by bringing a conductive tip portion into contact with a subject and a resistance value, a voltage value, and the like can be measured. Especially for probes for large currents (eg, several tens of amperes to several hundreds of amperes), it is necessary to secure a contact area to suppress heat generation, etc., and the tip of the probe is formed so as to contact the subject at multiple points. Has been.

  By the way, since the specimen to be examined is used in the atmosphere, an oxide film may be formed on the surface layer of the specimen. In some cases, the electrode member or the like is subjected to high resistance coating, for example, chromate treatment. Since the contact resistance increases when the probe is pressed onto the high-resistance film such as the oxide film or high-resistance coating formed on the surface of the specimen in this way, stable contact with low resistance can be ensured. It will disappear. Therefore, it is desirable to remove or break through the high resistance film to bring the probe tip into contact.

  For example, Patent Document 1 describes a method of penetrating a high resistance film by making the tip of a probe have a sharp multi-vertex shape and pressing the tip of the probe against the surface layer of a subject.

  However, when the tip of the probe has a sharp multi-vertex shape, it touches the surface of the subject on a virtual plane connecting these sharp multi-vertices, so the contact point follows the unevenness and inclination of the subject surface. Cannot be changed. For this reason, there is a problem that only a smooth surface having no inclination can be handled, and the application is limited. Moreover, even if it is a smooth surface without inclination, there is a problem that the contact state is not stable when there is a small undulation or the like. In addition, since a plurality of vertices must be processed to a uniform height, there is a problem that a high processing technique is required and the cost is increased.

  As a method for solving such a problem, Patent Document 2 discloses that a plurality of contact portions that diverge radially are formed at the tip of a probe, and a surface layer of a subject is scrubbed with the plurality of contact portions to form a high resistance film. A removal method has been proposed. According to such a method, each of the plurality of contact portions changes the contact point following the unevenness or inclination of the surface of the subject, so that stable contact can be ensured even when there is unevenness or inclination of the electrode. Can do. In addition, since each contact portion is pressed against the electrode and scrubbed, the high resistance film on the electrode surface can be removed, thereby preventing an increase in contact resistance due to the high resistance film and ensuring stable contact with low resistance. be able to. Furthermore, even when the electrode material of the subject is fixed to the probe tip, the fixed electrode material can be peeled off by a scrubbing operation, thereby preventing an increase in contact resistance and ensuring stable contact with low resistance. can do. In addition, since a punching process of a press can be used as a manufacturing method, it can be manufactured at low cost.

Japanese Utility Model Publication No. 62-114366 JP 2011-137791 A

However, since the structure described in Patent Document 2 described above is a structure that scrubs the surface of the subject by elastically deforming a plurality of contact portions, unrecoverable strain may remain in the contact portions. There is a possibility that the contact part may be damaged due to fatigue. As described above, when the contact portion is distorted or fatigued, stable low resistance contact cannot be realized.
Therefore, an object of the present invention is to provide a high-current probe that can maintain a stable low-resistance contact for a long period of time without causing distortion or fatigue failure.

  The present invention has been made to solve the above-described problems, and is characterized by the following.

The invention according to claim 1 is a high-current probe in which a contact member for electrical conduction is provided at a tip portion of a base member made of a conductor, and the contact member is fixed to a tip surface of the base member. A plate, comprising: a fixed portion that is fixed in contact with the distal end portion of the base member; and a plurality of legs that protrude radially from the fixed portion, and the contact member is pressed against the subject to, together with the plurality of legs is in contact with the object while deforming pushed apart to the subject thus radially configured to scrub the surface of the object with the tip inside edge of said plurality of legs are, at the tip portion of said base material, said contact member to contact with the subject when pressed against the subject, a stopper for restricting movement of the subject direction of the contact member is projected Features.

  The invention described in claim 2 is characterized in that, in addition to the feature of the invention described in claim 1, the stopper is provided so as to protrude near the center of the contact member.

  The invention described in claim 3 is characterized in that, in addition to the features of the invention described in claim 1 or 2, the stopper can be used as a voltage measuring sensing pin for four-terminal measurement.

  The invention described in claim 1 is as described above, and when the contact member is pressed against the subject, the plurality of leg portions are spread and deformed by the subject and come into contact with the subject. That is, since the plurality of leg portions are deformed along the unevenness and inclination of the electrode, stable contact can be ensured regardless of the unevenness and inclination of the electrode. In addition, since the tip of each leg is pressed against the electrode and scrubbed, the high resistance film on the electrode surface is removed, so that stable contact with low resistance can be ensured. Further, even when the electrode material of the subject is fixed to the tip of the leg portion, the fixed electrode material can be peeled off by the scrubbing operation, so that stable contact can be ensured with low resistance. In addition, since a punching process of a press can be used as a manufacturing method, it can be manufactured at low cost. Further, even if the contact member is worn or deteriorated, it is only necessary to replace the contact member, so that the operating cost of the high-current probe can be greatly reduced.

  Furthermore, a stopper that abuts the subject when the contact member is pressed against the subject and restricts movement of the contact member in the subject direction protrudes from the distal end portion of the base member. The deformation amount of the leg portion is limited, and the stress generated when the leg portion is deformed can be within the elastic region of the leg portion (preferably within the fatigue limit). Therefore, even when the high-current probe is repeatedly used, distortion and fatigue breakdown can be suppressed and stable low-resistance contact can be maintained for a long time.

  Further, the invention according to claim 2 is as described above, and the stopper is provided so as to protrude near the center of the contact member, so that the deformation suppression by the stopper is substantially evenly applied to all the leg portions. Can act.

  Further, the invention according to claim 3 is as described above, and the stopper can be used as a voltage measuring sensing pin for four-terminal measurement, so that a high-current probe can also be used for four-terminal measurement. Can be performed with high accuracy.

It is an external appearance perspective view of the probe for large currents. It is an external appearance perspective view of a circular plate (contact member). It is sectional drawing of the probe for large currents. It is a partially expanded sectional view of the probe for large currents. It is explanatory drawing which shows a mode that the surface layer of a subject is scrubbed with a leg part. It is a side view of the probe for large currents which concerns on the modification which changed the number of legs. It is an external appearance perspective view of the probe for large currents which concerns on the modification using a rectangular plate (contact member). It is an external appearance perspective view of a rectangular plate (contact member). It is sectional drawing of the probe for large currents which concerns on a modification. It is a partial expanded sectional view of the probe for large currents concerning a modification.

  Embodiments of the present invention will be described with reference to the drawings.

  The high-current probe 10 according to the present embodiment establishes an electrical connection with the subject 30 by bringing a conductive tip into contact with the subject 30, and determines the resistance value, voltage value, and the like of the subject 30. Used to measure. As shown in FIG. 1, the large current probe 10 ensures a contact area by contacting the subject 30 at multiple points at the tip, and is used at a large current (for example, several tens to several hundreds of amperes). But heat generation can be suppressed.

  As shown in FIGS. 1 and 2, the large current probe 10 includes a sleeve 11, a biasing member 12, a plunger 13, a circular plate 14, a stopper 15, and insulating collars 16 and 17. ing.

  The sleeve 11 is a cylindrical member made of a conductor as shown in FIG. 3, and holds a plunger 13 in a hollow portion so as to be slidable. The sleeve 11 is used, for example, by forming a hole in a board made of synthetic resin and inserting the hole into the hole. The board to which the sleeve 11 is fixed in this manner is disposed so as to face and separate from the subject 30 (electrode). When it is desired to establish an electrical connection, the tip of the high current probe 10 (more specifically, a circular plate 14 described later) is pressed against the subject 30 by bringing the board close to the subject 30. Can be contacted. On the other hand, when the tip of the high current probe 10 is desired to be in a non-contact state with respect to the subject 30, the tip of the high current probe 10 is moved by moving the board away from the subject 30. 30 can be in a non-contact state.

  The urging member 12 is a spring member for urging a plunger 13 which will be described later, and urges the plunger 13 in a direction protruding from the sleeve 11. By providing the urging member 12, stable contact can be secured by the elastic force of the urging member 12 when the tip of the plunger 13 is pressed against the subject 30.

  The plunger 13 (base member) is made of a conductor, and is inserted into the sleeve 11 and held so as to be movable back and forth as shown in FIG. The plunger 13 can connect an electric wire to the rear end portion 13c, and can be electrically connected to a measuring device (not shown) by the electric wire. A circular plate 14 for electrical conduction, which will be described later, is fixed to the distal end portion 13a of the plunger 13. Further, the plunger 13 is a hollow member as shown in FIG. 3, and a through hole 13b is formed in the longitudinal direction.

  The circular plate 14 (contact member) is made of a conductor, and is fixed in a state where it contacts the tip portion 13a of the plunger 13 as shown in FIG. Specifically, it is fixed to the distal end surface of the plunger 13 by being sandwiched between an insulating collar 16 and a plunger 13 which will be described later. The circular plate 14 can be manufactured by processing, for example, a beryllium copper alloy. Further, durability may be improved by increasing rigidity by aging treatment. Moreover, durability and electrical conductivity may be improved by applying nickel gold plating.

  As shown in FIG. 2, the circular plate 14 has a shape obtained by processing a single plate into a crown shape, and is manufactured, for example, by punching a press. The circular plate 14 includes a central circular fixing portion 14a and a plurality of leg portions 14c projecting radially from the fixing portion 14a.

  The fixing portion 14a is a portion that is fixed in contact with the distal end portion 13a of the plunger 13, and is a portion that is sandwiched and held between an insulating collar 16 and a plunger 13 described later. A round hole 14b is formed in the center of the fixed portion 14a so that a shaft portion 15c of a stopper 15 described later can be passed therethrough.

  The leg portion 14c is a portion that is formed to protrude from the outer peripheral edge of the fixed portion 14a at equal intervals, and is formed to protrude obliquely outward from the fixed portion 14a toward the subject 30. As shown in FIG. 5, when the plunger 13 is pressed against the subject 30, the leg portion 14 c is expanded by the subject 30 and contacts the subject 30 while being deformed. At this time, as shown in FIG. 5, the edge of the leg 14 c tip scrubs the surface layer of the subject 30, and the high resistance film formed on the surface layer of the subject 30 can be removed.

  Note that the number of the leg portions 14c may be appropriately changed according to the magnitude of the current as shown in FIG. Further, a plurality of circular plates 14 having different numbers of leg portions 14c may be provided, and the circular plates 14 may be replaced to change the number of leg portions 14c according to the use environment.

  The stopper 15 is a rod-shaped member as shown in FIG. 3, and has a flat surface 15a formed at the tip of the shaft portion 15c, and a conical protrusion 15b formed at the center of the flat surface 15a. The stopper 15 is arranged so that the shaft portion 15 c penetrates the through hole 13 b of the plunger 13, and the flat surface 15 a of the tip portion projects in the tip direction of the plunger 13. Further, as shown in FIG. 4, the protrusion 15b protruding from the flat surface 15a protrudes toward the subject 30 in the same manner as the leg portion 14c of the circular plate 14, but the protrusion amount of this protrusion 15b is the leg portion 14c. (In other words, the protrusion 15b is formed so as not to protrude from a virtual plane connecting the tips of the leg portions 14c).

  The stopper 15 abuts on the subject 30 when the plunger 13 is pressed against the subject 30 and restricts the movement of the contact member 14 in the direction of the subject 30. The stopper 15 restricts the movement of the contact member 14, thereby suppressing the leg portion 14 c from being deformed beyond a predetermined range.

  Specifically, as shown in FIG. 5, when the plunger 13 is pressed against the subject 30, the leg portion 14 c is expanded and deformed by the subject 30, and the protrusion 15 b provided at the tip of the stopper 15 is the subject 15. Pierce 30. When the protrusion 15b pierces the subject 30 to a certain position, the plunger 13 cannot be pressed against the subject 30 any more. As described above, since the stopper 15 is provided, the plunger 13 is not pressed against the subject 30 more than necessary, and the leg portion 14c is expanded beyond the predetermined range and deformed. There is no such thing.

  The stopper 15 is arranged coaxially with the plunger 13, and the apex of the protrusion 15 b is provided on a perpendicular passing through the center of gravity of the circular plate 14. For this reason, the deformation suppression by the stopper 15 acts almost uniformly on all the leg portions 14c. The suppression by the stopper 15 is desirably set so that the maximum stress generated when the leg portion 14c is deformed is less than the yield point, more preferably less than the fatigue limit.

  As shown in FIGS. 3 and 4, the insulating collars 16 and 17 are cylindrical insulating members that are fitted and fixed in the through holes 13 b of the plunger 13. The stopper 15 described above is fixed to the plunger 13 by being press-fitted into the holes of the insulating collars 16 and 17.

  By the way, the stopper 15 according to the present embodiment can be used as a voltage measuring sensing pin for four-terminal measurement. That is, the stopper 15 is insulated from the plunger 13 and the circular plate 14 by being fixed via the insulating collars 16 and 17. In addition, an electric wire can be connected to the rear end portion 15d of the stopper 15, and can be electrically connected to a measuring device (not shown) for four-terminal measurement by the electric wire. In this way, the stopper 15 can be electrically connected to the measuring device by a separate system from the plunger 13 and the circular plate 14. Since the stopper 15 has a protrusion 15b at the tip, it is possible to break through the high-resistance coating on the surface of the subject 30 by the piercing of the protrusion 15b, and even when four-terminal measurement is performed. , Stable low-resistance contact can be realized.

  As described above, according to the present embodiment, when the plunger 13 is pressed against the subject 30, the plurality of leg portions 14 c are spread and deformed by the subject 30 so as to come into contact with the subject 30. It has become. That is, since the plurality of leg portions 14c are deformed along the unevenness or inclination of the electrode, stable contact can be ensured without being influenced by the unevenness or inclination of the electrode. Further, since the high resistance film on the electrode surface is removed by scrubbing the tip of each leg portion 14c against the electrode, stable contact can be ensured with low resistance. Furthermore, even when the electrode material of the subject 30 is fixed to the tip of the leg 14c, the fixed electrode material can be peeled off by the scrubbing operation, so that stable contact can be ensured with low resistance. it can. In addition, since a punching process of a press can be used as a manufacturing method, it can be manufactured at low cost. Further, even if the circular plate 14 is worn or deteriorated, only the circular plate 14 needs to be replaced, so that the operating cost of the high-current probe 10 can be greatly reduced.

  Further, a stopper 15 that abuts the tip 13a of the plunger 13 against the subject 30 when the circular plate 14 is pressed against the subject 30, and prevents the leg 14c from deforming beyond a predetermined range. Therefore, the deformation amount of the leg portion 14c is limited, and the stress generated when the leg portion 14c is deformed can be within the elastic region (preferably within the fatigue limit) of the leg portion 14c. Therefore, even when the high-current probe 10 is repeatedly used, distortion and fatigue breakdown can be suppressed and stable low-resistance contact can be maintained for a long time.

  Further, since the stopper 15 is provided so as to protrude near the center of the circular plate 14, the deformation suppression by the stopper 15 can be applied to all the leg portions 14c almost evenly.

  Further, since the stopper 15 can be used as a voltage measuring sensing pin for four-terminal measurement, the high-current probe 10 can be used for four-terminal measurement, and highly accurate measurement can be performed.

  In the above-described embodiment, the example in which the plunger 13 is used as the base member of the high current probe 10 has been described. However, the embodiment of the present invention is not limited thereto. For example, as shown in FIG. 7, a plate-like member 21 may be used as the base member. That is, even in the case of the high current probe 20 in which the object to be measured is sandwiched between the two plate-like members 21 and inspected, the same effect as that of the above-described embodiment is obtained by applying the structure of the present invention. Can be obtained.

  In the above-described embodiment, the example in which the circular plate 14 is used as the contact member of the high-current probe 10 has been described. However, the embodiment of the present invention is not limited thereto. For example, as shown in FIGS. 7 and 8, a rectangular plate 22 may be used as the contact member. In the example shown in FIGS. 7 and 8, the rectangular plate 22 includes a rectangular fixing portion 22a and a plurality of leg portions 22c protruding at substantially the same height from the outer peripheral edge of the fixing portion 22a. And the round hole 22b is formed in the gravity center of the fixing | fixed part 22a. By disposing the stopper 23 so as to penetrate the round hole 22b, the stopper 23 protrudes near the center of the rectangular plate 22. Thus, even when the shape of the contact member is changed, the same effects as those of the above-described embodiment can be obtained by applying the structure of the present invention.

  In the above embodiment, the stopper 23 can be used as a voltage measuring sensing pin for four-terminal measurement. However, the present invention is not limited to this, and a voltage measuring sensing pin for four-terminal measurement is provided separately from the stopper 23. Also good. For example, as shown in FIGS. 9 and 10, a four-terminal measurement probe 25 which is a voltage measurement sensing pin for four-terminal measurement may be provided so as to penetrate the stopper 23. In the example shown in FIGS. 9 and 10, the four-terminal measuring probe 25 is disposed in the hollow portion of the cylindrical needle guide portion 26 and is held by the needle guide portion 26 so as to be slidable back and forth. . The four-terminal measuring probe 25 is urged by a needle urging member 27 so as to protrude outward, and can be slid inward by being pressed against the subject 30. A connection portion 28 for connecting to the measurement device is provided behind the needle guide portion 26, and the four-terminal measurement probe 25 is electrically connected to the subject 30 by connecting the measurement device to the connection portion 28. Voltage measurement can be performed when connected. The four-terminal measurement probe 25 is insulated from the plunger 13 and the circular plate 14. In this way, if the voltage measuring sensing pin for four-terminal measurement is provided so as to penetrate the plunger 13 of the high-current probe 10, the high-current probe 10 can be used for four-terminal measurement, and the accuracy can be improved. High measurement can be performed.

10 Probe for large current 11 Sleeve 12 Biasing member 13 Plunger (base member)
13a tip portion 13b through hole 13c rear end portion 14 circular plate (contact member)
14a Fixed portion 14b Round hole 14c Leg portion 15 Stopper 15a Flat surface 15b Protrusion 15c Shaft portion 15d Rear end portion 16, 17 Insulating collar 20 Probe for high current 21 Plate member (base member)
21a Tip 22 Rectangular plate (contact member)
22a Fixed portion 22b Round hole 22c Leg portion 23 Stopper 25 Four-terminal measurement probe 26 Needle guide portion 27 Needle biasing member 28 Connection portion 30 Subject

Claims (3)

A probe for large current in which a contact member for electrical conduction is provided at the tip of a base member made of a conductor,
The contact member is a plate fixed to a front end surface of the base member, and a fixed portion fixed in contact with the front end portion of the base member, and a plurality of legs protruding radially from the fixed portion And comprising
Said contact member when pressed against the subject, together with the plurality of legs is in contact with the object while deforming pushed apart to the subject thus radially at the tip inner edges of said plurality of legs It is configured to scrub the surface of the subject ,
A stopper that abuts on the subject when the contact member is pressed against the subject and restricts movement of the contact member in the direction of the subject protrudes from the distal end portion of the base member. High current probe.   2. The high current probe according to claim 1, wherein the stopper is provided so as to protrude near the center of the contact member.   3. The high current probe according to claim 1, wherein the stopper can be used as a voltage measuring sensing pin for four-terminal measurement.

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