JP2002207049A - Contact pin for four-probe measurement, contact apparatus, device on side of object to be measured, and device on side of measuring circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide contact pins 1 and 1a capable of four-probe measurement, a contact apparatus capable of four-probe measurement therefore, a device 16a on the side of an object to be measured constituting the contact apparatus, and a device 16b on the side of a measuring circuit. SOLUTION: The contact apparatus comprises at least an inside terminal 2 as the contact pin 1 for four-probe measurement and a tubular circumferential- side terminal 5 sheathing the inside terminal 2 in an electrically insulated state and comprises two electric paths of an electric path reaching one end of the inside terminal 2 from its other end and an electric path reaching one end of the circumferential-side terminal 5 from its other end. The inside terminal 2 is, for example, used as an I-terminal for four-probe measurement, and the circumferential-side terminal 5 is used as a V-terminal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a four-probe measurement contact pin used for a contact device capable of four-probe measurement, a contact device using the contact pin, and an object to be measured which constitutes the contact device. The present invention relates to a device and a measuring circuit side device constituting the contact device.

[0002]

2. Description of the Related Art Electronic circuits using ICs, LSIs, transistors, and other electronic components are used in a large number of devices and equipment, and the applications thereof are steadily expanding. An electronic circuit is usually configured using a printed circuit board on which a wiring film is printed on one or both sides, and ICs, LSIs, transistors, and other various electronic components are mounted on the printed circuit board, and necessary soldering is performed. By doing so, an electronic circuit is configured.

[0003] Many of the devices and equipment using electronic circuits are required to be reduced in size, to have higher functions, and to have higher performance. As a result, the circuit configuration of electronic circuits is required to be more complicated and higher integration is required. ing. Therefore, the wiring of the printed circuit board is also miniaturized,
There is a tendency for high integration, which makes the measurement for the inspection difficult. This is because it is necessary to increase the precision of the arrangement density and arrangement position of the measurement probes by miniaturization and high integration of wiring. Nevertheless, the importance of testing is growing. The reason for this is that the finer the wiring and the higher the integration, the higher the incidence of short-circuit defects.

A tester provided with a measuring circuit is used for the inspection, and a contact device is used for electrically deriving each wiring film, electrodes, etc. of the printed circuit board to the measuring circuit. This contact device has a large number of probes on a plate, and one end of each probe is brought into contact with a portion to be electrically connected to a measurement circuit such as each wiring film of a printed circuit board,
In many cases, the other end is brought into contact with the tip of a cord connected to the measurement circuit. In this regard, the applicant company of the present application has filed Japanese Patent Application Nos. Hei 7-61728 and Hei 8-1834.
49 and Japanese Patent Application No. 10-66333.

FIG. 6 is an exploded perspective view showing one conventional example of such a contact device. In the drawing, a is a base plate, b, b,... Are measuring circuit mounting connectors mounted on the base plate a, and the connectors b, b,.
A printed circuit board on which a measuring circuit is configured is mounted on.

Reference numeral c denotes a relay board, which is supported on the base plate a by supports d, d, d, and d above and substantially parallel to the base plate a. The relay board c is provided with a large number of cable mounting holes, and the ends of the cables e, e,. Are inserted and fixed, and the ends of the core wires f, f,... Protrude from the upper surface of the relay board c by a certain length. The ends of the cables e, e,... On the side opposite to the side mounted on the cable mounting holes of the relay board c are connected to the terminals of the measurement circuit mounting connectors b, b,. ing.

[0007] h is a contact pin mounting board, which is formed by stacking a plurality of plates, and has a large number of contact pin storage holes
are formed, and the respective contact pin storage holes i,.
i,... have contact pins j, j,.
Is installed. Each of the contact pins j, j,...
Each has a sharp upper end, slightly projecting from the upper surface of the contact pin mounting board h, and a lower end slightly projecting from the lower surface of the board h.

The contact pin mounting board h
Are positioned and overlapped on the upper surface of the relay board c, and are fixed. At this time, the contact pins j, j,.
Are the core wires f, f,... Of the cables e, e,.
・ ・ Be sure to be in contact with and electrically connected between them. Therefore, each contact pin j, j,.
Are the terminals g, g,... Of the measuring circuit mounting connectors b, b,... Via the cables e, e,.
・ ・ It will be connected to

Therefore, a printed circuit board having a measuring circuit is mounted on each of the measuring circuit mounting connectors b, b,..., And in this state, a printed circuit board to be measured is mounted on the upper surface of the contact pin mounting board h. (Not shown)
Each probe point and each of the contact pins j, j,.
・ ・ Measurement can be performed by aligning the upper end with the target.

[0010]

By the way, none of the conventional contact devices can measure four probes. That is, for four-probe measurement, two terminals [I (current) terminal and V (voltage) terminal] are provided for one probe point.
In this case, it is necessary to separately make electrical contacts, which is conventionally impossible. And it is becoming a big problem that the contact device cannot cope with the four-probe measurement. The following specifically describes this problem.

For example, in the resistance measurement by the four probe measurement, taking a case where a parasitic resistance between two points A and B to be measured is measured as an example, a predetermined current is applied between the two points A and B. To determine the voltage drop between A and B,
The parasitic resistance is obtained by dividing the voltage drop by the current, and the measurement accuracy is extremely high. However, as described above, the contact pins for flowing current and the contact pins for measuring the voltage drop must be simultaneously contacted at each of the two points A and B, which is conventionally impossible at all. It was.

The printed circuit board is becoming more and more integrated, and the wiring film tends to be thinner and thinner. In addition, the wiring films are electrically connected to each other by lamination due to the multi-layer structure, and a contact resistance intervenes there. , The parasitic resistance tends to increase. Therefore, a need has arisen to accurately and reliably and quickly (efficiently) measure and inspect whether or not it exceeds an allowable limit.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and a four-probe measurement contact pin capable of four-probe measurement, a contact device using the contact pin, and a contact device It is an object of the present invention to provide a device under test and a circuit device on the measurement circuit side.

[0014]

According to the first aspect of the present invention, there is provided a contact probe for measuring a four-point probe, comprising: a middle terminal; and a cylindrical peripheral terminal fitted to the middle terminal in a state of being electrically insulated. And at least two electric paths: an electric path from one end of the middle terminal to the other end, and an electric path from one end to the other end of the peripheral terminal.

Therefore, according to the first aspect, the middle terminal and the peripheral terminal are applied to one probe point, so that the one terminal is connected to the other by the two electrically insulated terminals of the middle terminal and the peripheral terminal. Two electrical contacts can be made to the probe points, and each of the probe points can be electrically led to the other through the separate electrical paths. Therefore, four-probe measurement can be performed.

According to a second aspect of the present invention, there is provided a four-probe measuring contact pin having a pair of middle terminals, one end of which the pair of middle terminals are pointed outward and electrically insulated from the middle terminals. A pair of cylindrical peripheral terminals fitted inside in a state of being set, an inner conductive spring interposed between the pair of middle terminals, and an outer conductive contracted between the pair of peripheral terminals. And a gap between the pair of middle terminals, and at least middle terminal gap defining means for defining the inside conductive spring so as to maintain a contracted state by storing elasticity. I do.

Therefore, according to the four-probe measuring contact pin of the second aspect, the inner electric path is formed by one middle terminal, the inner conductive spring and the other middle terminal, and the inner conductive is formed. The spring can reliably maintain contact with each of the middle terminals required for forming the electric path by the spring force, and can absorb a mechanical load applied between the outer ends of the two middle terminals. On the other hand, an outer electric path is formed by one peripheral terminal, the outer conductive spring and the other peripheral terminal, and the outer conductive spring is connected to each peripheral terminal necessary for forming the electric path by the spring force. And the mechanical load applied between the outer ends of the two peripheral terminals can be absorbed.

Therefore, the contact pins are mounted in the respective contact pin receiving holes provided in the contact pin mounting board so as to penetrate the contact pin mounting board such that both ends thereof are exposed on both sides of the contact pin mounting board or project from both sides. With one four-probe measurement contact pin, two electric paths can be formed from one main surface side of the board or the connector to the other main surface side. Therefore, the two terminals, the middle terminal and the peripheral terminal, are electrically insulated from each other by contacting the middle terminal and the peripheral terminal of the four-probe measurement contact pin on the DUT side to one probe point. The terminal provided allows two electrical contacts to be made to the one probe point,
The probe point can be electrically led to each other separately in each of the above-mentioned different electric paths. Therefore, four-probe measurement can be performed.

The four-probe measuring contact pin according to claim 3 is the four-probe measuring contact pin according to claim 2,
One end of the peripheral terminal is formed in a cutout shape, leaving a part as a connection end.

Therefore, according to the four-probe measuring contact pin of the third aspect, it is possible to connect one end of the cable to the terminal provided with the connection end of the peripheral terminal of the middle terminal. Therefore, the terminal on the side where the connection end of the middle terminal and the peripheral terminal is formed can be used as the cable connection end. Therefore, it can be used as an electrical connection means between the measurement circuit side cable and the DUT side cable by being attached to the DUT side connection tool and the measurement circuit side connection tool of the contact device described later.

According to a fourth aspect of the present invention, there is provided a contact device having at least a middle terminal and a cylindrical peripheral terminal externally fitted to the middle terminal while being electrically insulated from the middle terminal. Each of a plurality of four-probe measurement contact pins having two electric paths, an electric path to an end and an electric path from one end of the peripheral terminal to the other end, passes through the contact pin mounting board. In each of the plurality of contact pin housing holes formed as described above, the outer ends of the middle terminal and the peripheral terminal are mounted on the main surfaces of the contact pin mounting board so as to be exposed or protrude from the main surfaces. The outer end of each middle terminal and each peripheral terminal that is exposed on one main surface of the contact pin mounting board or protrudes from both main surfaces is electrically connected to one or a plurality of terminals of the measuring circuit mounting connector. It is characterized by becoming.

Therefore, according to the contact device of the fourth aspect, if the peripheral terminal and the middle terminal of each four-probe measurement contact pin are respectively brought into contact with the same probe point of the DUT, each probe point Two electrical contacts are made each time, and each probe point can be connected to two different terminals of the connector for mounting the measuring circuit, and thus four probe measurement can be performed.

According to a fifth aspect of the present invention, in the contact device of the fourth aspect, an outer end of each of the middle terminal and each of the peripheral terminals exposed on one main surface of the contact pin mounting board or protruding from both main surfaces. The electrical connection between each of the terminals of the connector for mounting a measuring circuit and the object-side cable having one end connected to the outer end of each of the middle terminal and the peripheral terminal, and the connection of the connector for mounting a measuring circuit. A measuring circuit-side cable having one end connected to the terminal, a DUT-side connector to which the other end of each of the DUT-side cables is connected, and a detachably connected to the DUT-side connector, The other end of each measurement circuit side cable is connected via a measurement circuit side connection tool connected thereto.

Therefore, according to the contact device of the fifth aspect, the part on the DUT side (DUT side device) by the detachable DUT-side connector and the DUT-side connector, and the measurement circuit side (Measurement circuit-side device). Therefore, for example, if a device for measuring four probes and a device for normal measurement are prepared as the device on the device under test, the contact device can be connected by connecting the device on the measuring circuit side and the device for measuring four probes. The contact device can be used for ordinary measurement by connecting the measurement circuit side device and the one for ordinary measurement used for four probe measurement. Therefore, the flexibility of the contact device can be improved.

According to a sixth aspect of the present invention, the device under test has at least a middle terminal and a cylindrical peripheral terminal externally fitted to the middle terminal while being electrically insulated from the middle terminal. Each of a plurality of four-probe measurement contact pins having two electric paths, an electric path from one end to the other end and an electric path from one end to the other end of the peripheral terminal, is connected to a contact pin mounting board. In each of a plurality of contact pin storage holes formed so as to penetrate through, the outer ends of the middle terminal and the peripheral terminal are exposed on both main surfaces of the contact pin mounting board or project from the both main surfaces. Then, the outer ends of each of the middle terminals and each of the peripheral terminals that are exposed on one main surface of the contact pin mounting board or protrude from both main surfaces are connected to the DUT side connector via the DUT side cable. Four probes stored in contact pin storage holes And characterized by being connected to the intermediate terminal or peripheral side terminal of the titration, the contact pins.

Therefore, according to the device under test according to the sixth aspect, one probe point is separately provided for each of the four probe measurement contact pins at the middle terminal and the peripheral terminal by using two electric paths and a probe. The contact device can be electrically led to the DUT-side connector via the DUT-side cable, and the contact device can be detachably (replaceable) with a measurement circuit-side device described later.

According to a seventh aspect of the present invention, there is provided a measuring circuit side device comprising: a four-probe measuring contact pin housed in a contact pin housing hole of a measuring object side connector which is detachable from a measuring object side connector for a contact device; The side terminal or the peripheral side terminal is connected to each terminal of a connector for mounting a measuring circuit to which the measuring circuit is mounted via a measuring circuit side cable.
Therefore, according to the measuring circuit side device of claim 7, the measuring object side connecting tool detachable from the DUT side connecting tool for the contact device, and each terminal of the measuring circuit mounting connector to which the measuring circuit is mounted, Since the connection is made by the measuring circuit side cable, the contact device can be configured to be detachable (replaceable) with the device under test according to the sixth aspect.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The contact device of the present invention basically comprises at least a middle terminal and a cylindrical peripheral terminal which is externally fitted to the middle terminal while being electrically insulated. Have
It has two electric paths: an electric path from one end of the middle terminal to the other end, and an electric path from one end of the peripheral terminal to the other end. To form a pair of middle terminals formed by bisecting the middle terminal, the pair of middle terminals are pointed to one end with a sharp end facing outward, and the middle terminals are electrically insulated. A pair of peripheral terminals formed by bisecting the cylindrical peripheral terminal that has been internally fitted in a state, an inner conductive spring interposed between the pair of middle terminals, and the pair of peripheral terminals; An outer conductive spring contracted between the side terminals, and a distance between the pair of middle terminals, a middle terminal distance regulation that regulates the inner conductive spring to maintain a contracted state by storing elasticity. Means can be said to be preferable. Incidentally, in order to prevent the pair of middle terminals from coming off from the pair of peripheral terminals, it is preferable to take measures to prevent the middle terminal from coming off. It is advisable to take a measure such as caulking so that the relative movement can be made. If the relative movement is not allowed, the load may be absorbed by the spring force of the inner conductive spring, and the function of reliably making an electrical connection by contact may be impaired.

If one end of each of the peripheral terminals of the four-probe measurement contact pin is formed in a cutout shape, leaving a part as a connection end, the four-probe measurement contact pin is covered. A four-probe measurement contact that is connected to a cable at one end and is attached to a measurement tool, not as a four-probe measurement contact pin that directly contacts and electrically contacts each probe point on a printed circuit board. Suitable for use as a pin. In this case, the other end of the four-probe measuring contact pin is brought into contact with the other end of the four-probe measuring contact pin attached to the measuring instrument detachably connected to the measuring instrument, The measuring contact pins make electrical contact between the cables.
This is because one end of the peripheral terminal is cut off, leaving a part as a connection end, so that one end of the cable can be connected to the middle terminal. This is because it is easy to connect one end of the cable to the terminal.

The contact device of the present invention basically has at least a middle terminal and a cylindrical peripheral terminal externally fitted to the middle terminal in an electrically insulated state. Each of a plurality of four-probe measurement contact pins having two electric paths, an electric path from one end to the other end and an electric path from one end to the other end of the peripheral terminal, is connected to a contact pin mounting board. In each of a plurality of contact pin storage holes formed so as to penetrate through, the outer ends of the middle terminal and the peripheral terminal are exposed on both main surfaces of the contact pin mounting board or project from the both main surfaces. Then, the outer ends of each of the middle terminals and each of the peripheral terminals that are exposed on one main surface of the contact pin mounting board or protrude from both main surfaces are electrically connected to the terminals of one or more measuring circuit mounting connectors. Connected, but each of the four Electrical connection of the outer end of the middle-side terminal and the peripheral terminal of the needle for measurement contact pins, the terminals of the measuring circuit mounting connector, it is preferable to be performed via a cable. Then, the electrical connection between the cable and the outer ends of the middle terminal and the peripheral terminal is made by passing one end of the cable through the relay board, peeling off the insulating coating, and slightly projecting the tip of the exposed core wire from the relay board. Then, the contact pin mounting board is positioned on the relay board and overlapped, and one end of the middle terminal and the peripheral terminal of the four-probe measurement contact pin mounted on the contact pin mounting board is brought into contact with the front end of the front line of each cable. It is good to do it by doing.

Then, a pair of connecting tools detachably connected to each other is interposed at the intermediate portion of each of the cables, and the contact device is connected to a portion on the device under test side, that is, a device on the device under test side,
It is preferable to be able to detachably divide into two parts on the measurement circuit side, that is, the measurement circuit side device. Note that the electrical connection between the cables by a pair of connectors that are detachably connected to each other, that is, the connector on the DUT side and the connector on the measurement circuit side, includes a middle terminal and a peripheral terminal at one end of the cable. The inside of the four-probe measurement contact pin, which is mounted by mounting the connected four-probe measurement contact pin, for example, the four-probe measurement contact pin according to claim 3 and fixing the connecting members. This can be performed by bringing the terminals and the peripheral terminals into contact with each other.

In this way, a contact device for four-probe measurement is constructed by connecting one device on the measurement circuit side to, for example, a device for four-probe measurement. By connecting to the side device, a contact device for ordinary measurement can be constituted, and one device on the measurement circuit side can be used for both four-probe measurement and ordinary measurement. Incidentally, as the contact device according to the present invention,
At the present time, two contacts can be made for each of the 512 probe points, and therefore, a product having the number of contacts reaching 1024 could be commercialized. There is a good chance of increasing the number.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments. FIGS. 1A, 1B and 2 show one embodiment of the contact pin for four-probe measurement according to the present invention.
(A) is an exploded perspective view, (B) is a perspective view of a contact pin for four-probe measurement, and FIG. 2 is a longitudinal sectional view. The contact pins for four-probe measurement according to this embodiment are shown in FIGS. 4 and 5 and are described below in detail in a contact device (one embodiment of the contact device of the present invention). It is used as a four-probe measurement contact pin for conducting electrical derivation through two independent electric paths from a point, and is mounted on a contact pin mounting board of a contact device. The number of four-probe measurement contact pins mounted on the contact pin mounting board is, for example, 512, but may increase in the future.

1 is a contact pin for four-probe measurement,
Is a pair of middle terminals made of a conductive material, one end (outer end) of each of the middle terminals 2 and 2 is pointed, and the middle part is smaller in diameter than both ends. Side terminals 2, 2
Is held in one middle terminal holding cylinder 3, and the distance between the middle terminals 2, 2 is regulated so as not to exceed a predetermined value. In this embodiment, the middle terminal 2 is an I (current) terminal.

The above-mentioned spacing is regulated by inserting the inner end portions of the middle terminals 2 and 2 into the middle terminal holding tube 3 and bending both ends of the middle terminal holding tube 3 inward. This is done by engaging the part with the inserted inner end part. The outer peripheral surface of the middle terminal holding cylinder 3 is coated with an insulating material. This is because it is necessary to electrically insulate between the middle terminals 2 and 2 and the peripheral terminals (5 and 5) described later.

Also, portions of the middle terminals 2 and 2 which are in direct contact with peripheral terminals (5, 5) described later are coated with an insulating material. Reference numeral 4 denotes an inner conductive spring contracted between the middle terminals 2. The position of the middle terminals 2 and 2 is regulated by the middle terminal holding cylinder 3 so that the distance between the middle terminals 2 and 2 does not exceed a predetermined value. In this state, the springs 4 are urged away from each other by the elastic force of the spring 4.

Reference numerals 5 and 5 denote a pair of peripheral terminals, each of which is formed of a conductive tubular body having both ends open. The peripheral terminals 5 and 5 are electrically insulated from the middle terminals 2 and 2 respectively. It is fitted in a state where it is set. Specifically, as described above, the outer peripheral surfaces of the large-diameter portions of the middle terminals 2 and 2 and the outer peripheral surface of the middle terminal holding cylinder 3 are insulated and coated to form the middle terminals 2 and 2.
Are internally fitted to the peripheral terminals 5, 5 in an electrically insulated state. At the outer end of one of the peripheral terminals 5, a plurality of sharp portions 6 are provided along the circumferential direction, and a plurality of sharp portions 6 are arranged along the circumferential direction. (Printed circuit board) side, and the opposite side is the measurement circuit side. In this embodiment, the peripheral terminal 5 is used as a V (voltage) terminal.

Reference numeral 7 denotes an outer conductive spring interposed between the pair of peripheral terminals 5,5. Reference numerals 8 denote outwardly-facing steps formed by making the outer diameters of the peripheral terminals 5, 5 smaller on the outside than on the inside, and are provided on the contact pin mounting board (two-dot chain line in FIG. 2, reference numeral 20). When the peripheral terminals 5.5 are housed in the contact pin housing holes 21 by being engaged with the step portions 22 on the contact pin mounting board side when housed in the contact pin housing holes 21, respectively. The interval is regulated so as not to exceed a predetermined value. As described above, the outer conductive spring 7 is interposed between the peripheral terminals 5 and 5, and the peripheral terminals 5 and 5 are moved outward in a state where the interval is regulated by the spring force of the spring 7. Being energized.

The middle terminals 2, 2 are partially caulked, for example, so that the peripheral terminals 5, 5 do not come off from the peripheral terminals 5, 5. 9, 9, 9, 9 are the caulking portions.

Such a contact pin 1 for four-probe measurement
Is set in each contact storage hole 21 of the contact pin mounting board 20 (indicated by a two-dot chain line), the step portions 8 of the four-probe measurement contact pin 1 are
Of the four-probe measuring contact pin 1 from the contact housing hole 21 is prevented.

An object to be measured, for example, a printed circuit board is applied to one main surface of the contact pin mounting board 20, and one of relay boards (24) to be described later is mounted on the other main surface of the contact pin mounting board 20, for example. And the outer ends of one middle terminal 2 and one peripheral terminal 5 of each contact pin 1 are brought into contact with each probe point (one probe point) of the printed circuit board,
Connect the outer ends of the other middle terminal 2 and peripheral terminal 5 to the relay board (2
4) A pair of cables (25a) exposed on the main surface
Is brought into contact with the core wire distal end surface from which the insulating coating at the distal end of the core wire has been peeled off.

The inner conductive spring 4 between the middle terminals 2 and the outer conductive spring 7 between the peripheral terminals 5, 5 receive a pressurizing load received by the printed circuit board and the relay board (24). And the electrical contact between the spring 4 and the middle terminals 2 and 2 and the electrical contact between the spring 7 and the peripheral terminals 5 and 5 can be reliably established. The cables (2) of the relay board (24)
5a).

Accordingly, it is possible to perform the measurement by the four-probe measurement method on the printed board by the measurement circuit in which the cable (25a) of the relay board (24) is electrically connected indirectly, for example. The contact device (15) using the four-probe measurement contact pin 1 will be described later in detail.

FIGS. 3A to 3C show a second embodiment 1a of a contact pin for four-probe measurement according to the present invention.
(A) is an exploded perspective view, (B) is a perspective view, and (C) is an arrow view of the middle terminal and the peripheral terminal viewed along arrow C. The four-probe measuring contact pin 1a is used in the contact device shown in FIG. 4, and in that respect, the first embodiment of the four-probe measuring contact pin of the present invention shown in FIGS.
Are common, but differ in some uses and structures.

First, the application will be described. In the contact device, which will be described later in detail, in the relay board (2)
0) and the terminal (30) of the connector (27) for mounting the measuring circuit
A pair of connectors (17a, 17b) detachably connected to each other is interposed in a cable (25) for connecting the cable (25).
5) The contact pin 1 for four-probe measurement as a contact pin for four-probe measurement attached to one end of
Use a. In this respect, the contact pin is different from the four-probe measurement contact pin 1 which directly contacts the probe point of the printed circuit board to be measured and performs electrical derivation. That is, the four-probe measuring contact pin 1a performs electrical relay.

Next, the structure differs in two points. First, the outer end of one of the peripheral terminals 5 is partially connected to the connection end 1.
Notched to remain as 0. This is to make it easier to connect one end of the cable to the end of the middle terminal 2 by soldering or the like. Contact pin 1 for this four probe measurement
a is structurally different from the four-probe measurement contact pin 1 which is not directly connected to the cable, and the side where the connection end 10 is formed becomes the side to be connected to the cable, and Is mounted from the side opposite to the side where the cable is connected.

Second, the pointed portion 6 provided at the outer end of the other peripheral terminal 5 is located on the opposite side of the middle terminal 2 (a distance of 180 ° around the middle terminal). 3), the sharp portions 6, 6 and the middle terminal 2 are arranged so as to be aligned with each other as shown in FIG. This is different from the four-probe measurement contact pin 1 in which the position is not restricted.

FIG. 4 shows the contact pin 1 for four-probe measurement.
FIG. 11 is a perspective view showing a schematic configuration of a contact device for four-probe measurement using a large number of samples and 1a, that is, a first embodiment 15 of the contact device of the present invention. The contact device 15
The device under test (the first embodiment of the device under test of the present invention) 16a and the device under test (the first embodiment of the device under test of the present invention) 16b comprise the device under test. The object-side device 16a and the measurement circuit-side device 16b are configured to be interchangeable with each other by an object-to-be-measured side connection tool 17a and a measurement circuit-side connection tool 17b that are detachably connected to each other.

First, the device under test 16a will be described. Reference numeral 20 denotes a contact pin mounting board, which is formed by laminating a plurality of insulating plates, and has a large number of contact pin storage holes 21 (see FIG. 2) for receiving the four-probe measurement contact pins 1. Each contact pin receiving hole 21 is provided with one contact pin 1 for four-probe measurement as described above. Specifically, the outer ends of the right-side middle terminal 2 and the peripheral terminal 5 of the four-probe measurement contact pin 1 in FIG.
2 protrudes from the upper main surface, that is, the upper surface 20a, and the outer ends of the left middle terminal 2 and the peripheral terminal 5 in FIG.
The four probe contact pins 1 are mounted on the contact pin mounting board 20 so as to be exposed or projected.

Reference numeral 24 denotes a relay board. The board 24 is also formed by laminating a plurality of insulating plates, for example. It penetrates in correspondence with the side terminal 5. Then, into the respective cable mounting holes, one end of the DUT side cable 25a, one end of which is stripped of the insulating coating to a predetermined length to expose the core wire, is inserted from below the relay board 24, and the tip of the core wire is inserted. The relay board 24 is fixed so as to slightly protrude from the upper main surface, that is, the upper surface thereof.

Each cable mounting hole of the relay board 24 is formed with a downward step by making the upper part smaller in diameter than the lower part, and the end surface of the insulating coating from which the tip of the object side cable 25a is peeled off is formed. The vertical position of the cable is defined by engaging the step. And all the cables 25a, 25a, ...
After the mounting and fixing, the core wire protruding from the upper surface of the relay board 24 is polished on a surface parallel to the board 24 so that the amount of protrusion of the core wire of each cable 25a is made constant.

Then, the contact pin mounting board 2
0 and the upper surface of the relay board 24 are positioned and overlapped with each other, and the middle terminal 2 and the peripheral terminals of the contact pins 1 mounted in the respective contact pin receiving holes 21 of the contact pin mounting board 20 by the overlapping. Side terminal 5
Are in contact with the end surfaces of the core wires of the respective cables 25a, 25a mounted in the respective cable mounting holes of the relay board 24. Incidentally, in the present embodiment, the number of cable mounting holes is
(For example, 1024) of the number (for example, 512).

The other end of each of the DUT side cables 25a,
That is, the end of the relay board 24 on the side opposite to the side mounted on each cable mounting hole has the core wire having the contact pin 1 shown in FIG.
a is connected to the connection terminal 10 of the middle terminal 2 or the peripheral terminal 5 by soldering or the like. That is, half of the DUT side cable 25 a is connected to the middle terminal 2 of the contact pin 1 a, and the other half is connected to the connection end 10 of the peripheral terminal 5.

Each of the four probe measuring contact pins 1a connected to the two cables 25a, 25a at the connection end 10 of the peripheral terminal 5 and the middle terminal 2 is connected to the object-to-be-measured connector 17a, respectively. Attached to. This mounting will be described later in detail with reference to FIG.

Next, the measuring circuit side device 16b will be described. Reference numeral 26 denotes a base plate, on which a plurality of measuring circuit mounting connectors 27 are provided (however, there may be only one connector), and mounting holes 28, 28 for mounting the device 16a to be measured are provided. 28, 28 are formed, and the mounting legs 29, 29, 29, 29 of the device 16a to be measured are inserted and fixed into the mounting holes 28, 28, 28, 28.

One end of each of the terminals 30, 3 of the measuring circuit mounting connectors 27, 27,.
The other end of each of the connection terminals 10 is connected to the middle terminal 2 or the peripheral terminal 5 of the four-probe measurement contact pin 1a whose core is shown in FIG.
Are connected by soldering or the like. That is, as in the case of the DUT side cable 25a, half of the measurement circuit side cable 25b is connected to the middle terminal 2 of the four probe measurement contact pin 1a, and the other half is connected to the connection terminal 10 of the peripheral terminal 5. It is connected to the.

Each of the four-probe measurement contact pins 1a connected to the two cables 25b, 25b at the connection end 10 of the peripheral terminal 5 and the middle terminal 2 is connected to the measurement circuit side connector 17b. Be attached. This mounting will be described later in detail with reference to FIG. The measuring circuit side connection tool 17b is detachably connected to the DUT side connection tool 17a.
And the object-side cable 17b corresponding thereto are electrically connected via the four-probe measurement contact pin 1a,
A contact device 15 for four-probe measurement is configured,
The connection between the connectors 17a and 17b will also be described with reference to FIG.

FIG. 5 is a cross-sectional view showing the DUT-side connector 17a and the measuring circuit-side connector 17a connected to each other. The two connectors 17a and 17b have exactly the same structure, while I will explain only. Reference numeral 40 denotes a contact pin storage main body, which is formed by stacking a plurality of plate bodies, and has a plurality of contact pin storage holes 41, 41,... For storing the four probe contact pins 1a. .
Each contact pin storage hole 41 is provided with a four-probe measurement contact pin 1a. Specifically, in the contact pin housing body 41, the connection pins 10 of the peripheral terminal 5 and the measurement circuit side cables 25b, 25b are connected to the middle terminal 2, respectively. , 25b are inserted from the side opposite to the side to which they are connected, and the peripheral terminal 5 and the intermediate terminal 2 are separated from the peripheral terminal 5 and the distal end of the intermediate terminal 2 by an appropriate amount from the distal end surface of the contact pin housing body 41. It is mounted to protrude.

Reference numeral 42 denotes an intermediate cylinder externally fitted to the contact pin housing body 40, and reference numeral 43 denotes an external cylinder externally fitted to the intermediate cylinder 42, and a plurality of fastening holes 44, 4
4, 44, 44 are formed, and the fastening holes 44, 4
Tightening bolts for tightening the two connectors 17a and 17b are passed through 4, 44 and 44. A thread groove (male thread) 45 is formed on the outer periphery of the rear end. The contact pin housing hole 40 is fixed to the outer cylinder 43 at the rear flange portion by pins 46, 46, 46, 46. Reference numeral 47 denotes a spring contracted between the rear flange portion of the contact pin housing hole 40 and the intermediate cylinder 42. Reference numeral 48 denotes a rear mounting cylinder, which has a thread groove (female screw) 49 formed on the inner peripheral surface of the distal end portion. The thread groove 49 is screwed with the thread groove 45 on the outer peripheral surface of the outer cylinder 43. In this way, a large number of four-probe measurement contact pins 1a are held in the connection tool 17b.

Each of the four-probe measuring contacts 17b is disposed such that the tip end surfaces thereof are opposed to the connecting member 17a having the same structure, and are aligned and connected to the measuring circuit side cables 25b. Contact pin 1 for each four-probe measurement connected to the pin 1a and the DUT side cable 25a
a of the middle terminals 2 corresponding to each other, and fixed in a state where the peripheral terminals 5 are in contact with each other;
The load applied when the middle terminals 2 and the peripheral terminals 5 come into contact with each other is absorbed by the inner conductive spring 4 and the outer conductive spring 7, and reliable electrical conduction can be obtained. As a result, the two connecting members 17a and 17b are connected to form the contact device 15. still,
Many (eg, 1024) cables 17, 17,...
The connection tool is not necessarily limited to that shown in FIG. 5 as long as it can be divided into two parts and can be connected detachably.

According to such a contact device, if a printed circuit board (not shown), which is a device to be measured, is positioned and applied to the upper surface of the contact pin mounting board 20 of the device 16a to be measured, the printing is performed. Each probe point of the board can be independently led out to the printed circuit board with a built-in measuring circuit mounted on the measuring circuit mounting connector 27 independently by the middle terminal 2 and the peripheral terminal 5. Therefore, four-probe measurement becomes possible.

Coaxial cables are used as the cables 25a and 25b. The core conductor is connected to the middle terminal 2 of the four-probe measurement contact pin 1a, and the outer shield wire is connected to the periphery of the four-probe measurement contact pin 1a. It may be connected to the side terminal 5. In this case, the number of cables used is half that of the case of using a cable of an ordinary coated electric wire type.
That is, in a case where a 1024 cable is required in a case where a cable of an ordinary insulated wire type is used, for example, in a case where a coaxial cable is used, 512 cables may be used.
It turns out that. Further, a contact device for performing ordinary measurement may be configured by combining the device under test for ordinary measurement and the above-described device 17b for measuring circuit. Therefore, the measurement circuit-side device 17b can configure a four-probe measurement contact device or a normal measurement contact device depending on the combination partner.
The flexibility of the measurement circuit side device 17b can be increased.

Incidentally, when a normal measuring device and the above-mentioned measuring circuit side device 17b are combined to constitute a contact device for performing a normal measurement, the electric path passing through the peripheral terminal 5 becomes a play. , Only the electrical path passing through the middle terminal 2 functions.

[0064]

According to the first aspect of the present invention, the middle terminal and the peripheral terminal are applied to one probe point so that the one terminal is connected to the other terminal by the two electrically insulated terminals of the middle terminal and the peripheral terminal. Two electrical contacts can be made to the probe points, and each of the probe points can be electrically led to the other through the separate electrical paths. Therefore, four-probe measurement can be performed.

According to the four-probe measurement contact pin of the present invention, an inner electric path is formed by one middle terminal, the inner conductive spring and the other middle terminal, and the inner conductive spring is Due to the spring force, the contact with each of the middle terminals required for forming the electric path can be reliably maintained, and the mechanical load applied between the outer ends of the two middle terminals can be absorbed. On the other hand, an outer electric path is formed by one peripheral terminal, the outer conductive spring and the other peripheral terminal, and the outer conductive spring is connected to each peripheral terminal necessary for forming the electric path by the spring force. And the mechanical load applied between the outer ends of the two peripheral terminals can be absorbed.

Accordingly, the contact pins for four-probe measurement are inserted into each contact pin receiving hole provided in the contact pin mounting board so as to penetrate the contact pin mounting board so that both ends thereof are exposed on both sides of the contact pin mounting board or project from both sides. By mounting the four contact points on one board, two electrical paths can be formed from one main surface side of the board or the connector to the other main surface side with one four-probe measurement contact pin. Therefore, the two terminals, the middle terminal and the peripheral terminal, are electrically insulated from each other by contacting the middle terminal and the peripheral terminal of the four-probe measurement contact pin on the DUT side to one probe point. The two terminals can make two electrical contacts to the one probe point, and the probe points can be electrically led to each other through the separate electrical paths. Therefore, four-probe measurement can be performed.

According to the four-probe measurement contact pin of the third aspect, one end of the cable can be connected to the terminal on the side of the middle terminal on which the connection end of the peripheral terminal is provided. The terminal on the side where the connection end of the middle terminal and the peripheral terminal is formed can be a cable connection end, respectively. Therefore, it can be used as an electrical connection means between the measurement circuit side cable and the DUT side cable by being attached to the DUT side connection tool and the measurement circuit side connection tool of the contact device described later.

According to the contact device of the fourth aspect, if the peripheral terminal and the middle terminal of each four-probe measuring contact pin are brought into contact with the same probe point of the object to be measured, respectively, Two electrical contacts can be made and each probe point can be connected to two different terminals of the measuring circuit mounting connector. Therefore, four-probe measurement can be performed.

According to the contact device of the fifth aspect,
A part to be measured (device to be measured) and a part to be measured (device to be measured) are detachably divided into two parts by a removable object-side connector and the object-side connector. Can be. Therefore, for example, if a device for measuring four probes and a device for normal measurement are prepared as the device on the device under test, the contact device can be connected by connecting the device on the measuring circuit side and the device for measuring four probes. The contact device can be used for ordinary measurement by connecting the measurement circuit side device and the one for ordinary measurement used for four probe measurement. Therefore, the flexibility of the contact device can be improved.

According to the device under test according to the sixth aspect, one probe point is separately provided for each four-probe measurement contact pin at the middle terminal and the peripheral terminal by two electric paths and the device under test. The contact device can be electrically led out to the DUT-side connector via the side cable, and the contact device can be detachably (replaceable) with a measurement circuit-side device according to claim 7 described later.

According to the measuring circuit side device of the present invention, the measuring object side connecting tool detachable from the measuring object side connecting tool for the contact device, and each terminal of the measuring circuit mounting connector to which the measuring circuit is mounted. And the measurement circuit side cable, the contact device can be configured to be detachable (replaceable) with the device under test according to the sixth aspect.

[Brief description of the drawings]

FIGS. 1A and 1B show a first embodiment of a four-probe measurement contact pin according to the present invention, wherein FIG. 1A is an exploded perspective view and FIG. 1B is a perspective view.

FIG. 2 is a longitudinal sectional view showing a first embodiment of a four-probe measuring contact pin according to the present invention.

3 (A) to 3 (C) show a second embodiment of the four-probe measuring contact pin of the present invention, wherein FIG. 3 (A) is an exploded perspective view, FIG. 3 (B) is a perspective view, and FIG. ) Is an arrow view of the middle terminal and the peripheral terminal viewed along arrow C.

FIG. 4 is a perspective view showing a schematic configuration of a first embodiment of the contact device of the present invention.

FIG. 5 is a cross-sectional view showing the DUT-side connection tool and the measurement circuit-side connection tool in a connected state according to the first embodiment of the contact device of the present invention.

FIG. 6 is a perspective view showing one schematic configuration of a conventional example of a contact device.

[Explanation of symbols]

1, 1a ... contact pin for four-probe measurement, 2 ...
Middle terminal, 3 ... Middle terminal interval defining means (middle terminal holding cylinder), 4 ... Inner conductive spring, 5 ... Peripheral terminal, 6 ... Outer conductive spring, 10 · ..Connection end, 15 ... Contact device, 16a ... Device to be measured, 16b ... Measurement circuit side device, 17a ... Device to be connected, 17b ... Connection to measurement circuit Utensil, 20
... contact pin mounting board, 21 ... contact pin storage hole, 24 ... relay board, 25a ... object side cable, 25b ... measurement circuit side cable,
27 ··· Connector for mounting measurement circuit.

Claims (7)

[Claims] An intermediate terminal, and at least a cylindrical peripheral terminal externally fitted in an electrically insulated state with respect to the intermediate terminal, from one end of the intermediate terminal to the other end. A contact pin for four-probe measurement, comprising two electric paths, namely, an electric path to reach and an electric path from one end to the other end of the peripheral terminal. 2. A pair of middle terminals having at least one end sharp, and the pair of middle terminals are fitted inside with the one ends facing outward and electrically insulated from the middle terminals. A pair of cylindrical peripheral terminals, an inner conductive spring interposed between the pair of middle terminals, an outer conductive spring interposed between the pair of peripheral terminals, and the pair of outer terminals. A middle terminal spacing defining means for defining a spacing between the middle terminals so that the inner conductive spring maintains a contracted state by accumulating elasticity, and a contact pin for four-probe measurement. . 3. The terminal according to claim 2, wherein one end of one of the peripheral terminals is formed in a cutout shape, leaving a part as a connection end. Contact pin for probe measurement. 4. An electric path extending from one end to the other end of the middle terminal, the middle terminal having at least a cylindrical peripheral terminal externally fitted in a state electrically insulated from the middle terminal. A plurality of four-probe measurement contact pins each having two electric paths, one from the one end of the peripheral terminal to the other end, and a plurality of four-probe measurement contact pins formed so as to penetrate the contact pin mounting board. And mounting the outer ends of the middle terminal and the peripheral terminal on both main surfaces of the contact pin mounting board so as to project from the two main surfaces of the contact pin mounting board. An outer end of each of the middle terminals and each of the peripheral terminals that are exposed on the main surface or protrude from both main surfaces are electrically connected to one or a plurality of terminals of the measurement circuit mounting connector. Contact equipment. 5. An outer end of each of the middle terminal and each of the peripheral terminals that are exposed on one main surface of the contact pin mounting board or protrude from both main surfaces, and corresponding terminals of the measuring circuit mounting connector. The electrical connection between the DUT side cable having one end connected to the outer end of each of the middle terminal and the peripheral terminal, and the measurement circuit side having one end connected to the terminal of the measurement circuit mounting connector The cable, the DUT-side connector to which the other end of each of the DUT-side cables is connected, and detachably connected to the DUT-side connector,
5. The contact device according to claim 4, wherein the contact is made via a measuring circuit side connection tool to which the other end of each of the measuring circuit side cables is connected. 6. An electric path extending from one end to the other end of at least one of a middle terminal and a cylindrical peripheral terminal externally fitted in a state electrically insulated from the middle terminal. A plurality of four-probe measurement contact pins each having two electric paths, one from the one end of the peripheral terminal to the other end, and a plurality of four-probe measurement contact pins formed so as to penetrate the contact pin mounting board. And mounting the outer ends of the middle terminal and the peripheral terminal on both main surfaces of the contact pin mounting board so as to project from the two main surfaces of the contact pin mounting board. The outer ends of each of the middle terminals and each of the peripheral terminals that are exposed on the main surface or protrude from both main surfaces are connected to the contact pin storage holes of the DUT-side connector via the DUT-side cable. Inside of contact pin for probe measurement DUT side device for contact device, characterized by comprising connecting the child and the peripheral-side terminals. 7. The four terminals housed in the contact pin housing holes of the measuring circuit side connector which is detachable from the measuring object side connector for the contact device and the measuring object side connector for the contact device to which the measuring circuit is mounted. A measurement circuit side device for contact equipment, wherein the measurement circuit side device is connected to a middle terminal or a peripheral side terminal of the probe measurement contact pin via a measurement circuit side cable.