WO2019077743A1

WO2019077743A1 - Probe

Info

Publication number: WO2019077743A1
Application number: PCT/JP2017/038026
Authority: WO
Inventors: 政紀山口; 忠北原
Original assignee: 株式会社東陽テクニカ
Priority date: 2017-10-20
Filing date: 2017-10-20
Publication date: 2019-04-25
Also published as: JP6324648B1; JPWO2019077743A1; CN111226120A; CN111226120B

Abstract

A probe (100) for measuring electrical impedance of a specimen (10) is provided with: a shield conductor (101) as a hollow-structured first electrode having a closed space (104) for housing the specimen (10); and a center conductor (106) as a second electrode, which extends in the closed space (104), and which is insulated from the shield conductor (101). The center conductor (106) extends by having a gap between a wall section of the shield conductor (101) and the center conductor, and has the specimen (10) between the wall section and the shield conductor, and the closed space (104) is in a vacuum state or filled with an inert gas (110).

Description

probe

The present invention relates to a probe for electrical impedance measurement.

Probes for measuring the electrical impedance of a sample are known. For example, Patent Document 1 discloses a physical property measuring device that measures physical properties of an object to be measured placed in a special atmosphere such as a furnace. The physical property measuring device is configured to measure the electrical impedance of the sample of the object to be measured using a probe in the furnace. The probe is configured to descend through the receiving frame containing the sample and to move up and down relative to the sample placed on the upward surface of the receiving frame. The probe and the receiving frame are electrically connected to one and the other of both terminals of the impedance measurement meter, respectively.

Unexamined-Japanese-Patent No. 5-240816

In the physical property measuring device of Patent Document 1, each of the probe and the receiving frame constitutes an electrode in contact with the sample. In order to accurately measure the electrical impedance of the sample, it is necessary to maintain electrical insulation between the probe and the receiving frame regardless of changes in ambient temperature.

The present invention provides a probe which improves the electrical insulation between the sample, ie the electrodes in contact with the specimen.

A probe according to one aspect of the present invention is a probe for measuring the electrical impedance of a test object, and extends into the closed space, a first electrode of a hollow structure having a closed space for receiving the test object, And a second electrode insulated from the first electrode, the second electrode extending across the air gap between the first electrode and the wall of the first electrode, and sandwiching the sample between the wall and the second electrode. Said enclosed space is vacuum or filled with an inert gas.

According to the probe of the present invention, it is possible to improve the electrical insulation between the electrodes in contact with the sample.

FIG. 1 is a schematic cross-sectional side view showing an example of a state at the time of measurement of the probe according to the embodiment. FIG. 2 is a schematic cross-sectional side view of the probe of FIG. FIG. 3 is a schematic cross-sectional view along the line III-III in FIG. FIG. 4 is a schematic cross-sectional view showing a probe according to a modification of the embodiment in the same manner as FIG.

The present inventors examined a probe for measuring the electrical impedance of the specimen as described in the "Background Art" section. Heretofore, the electrical impedance of a material has been positioned as one of the basic physical properties of the material. Therefore, when a new material is developed, its electrical impedance is measured using a probe or the like. At this time, the electrical impedance of the material is measured in a temperature environment adapted to the purpose of use of the material. However, since the electrical insulation of the probe cable used for measurement, the jig of the probe holding the specimen, etc. changes according to the ambient temperature, it is accurate in a temperature environment far from room temperature. Measurement was difficult. For this reason, the present inventors examined a probe which reduces the influence of the measurement result received from the change of temperature environment. As a result of intensive studies, the present inventors have invented a probe for improving the electrical insulation between the electrodes in contact with the specimen as follows.

Therefore, a probe according to an aspect of the present invention is a probe for measuring the electrical impedance of a test object, and extends into the closed space, a first electrode having a hollow structure having a closed space for receiving the test object. A second electrode insulated from the first electrode, the second electrode extending across a gap between the first electrode and a wall of the first electrode, and the test piece between the second electrode and the wall; The enclosed space is vacuum or filled with an inert gas.

The probe according to an aspect of the present invention further includes an insulating holding member for holding the second electrode with respect to the first electrode, and the wall portion is configured to receive the test piece with the second electrode. And a second wall extending across the air gap between the first wall and the second electrode, wherein the holding member extends from the second wall to the second electrode and extends in at least one direction. May hold the second electrode.

In the probe according to one aspect of the present invention, at least two of the holding members may be arranged radially from the second electrode toward the second wall.

In the probe according to one aspect of the present invention, the holding member may be extendable from the second wall.

In the probe according to one aspect of the present invention, the second electrode may be provided slidably in a direction toward and away from the first wall.

The probe according to one aspect of the present invention may further include a biasing member that biases the second electrode toward the first wall.

The probe according to one aspect of the present invention is a probe connector electrically connected to each of the first electrode and the second electrode with an impedance measuring device, and detachably connected to an electrical connector of the impedance measuring device. You may provide further.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Each embodiment described below shows one specific example. Numerical values, shapes, materials, components, arrangement positions and connection forms of components, steps (steps), order of steps, and the like shown in the following embodiments are merely examples, and the present invention is limited. is not. Further, among the components in the following embodiments, components not described in the independent claim indicating the highest concept are described as arbitrary components.

Further, in the following description of the embodiments, expressions accompanied by “abbreviation” such as substantially parallel or substantially orthogonal may be used. For example, “substantially parallel” means not only completely parallel but also substantially parallel, that is, including, for example, a difference of several% or so. The same applies to expressions accompanied by other "abbreviations". Further, each drawing is a schematic view, and is not necessarily illustrated exactly. Further, in the drawings, substantially the same components are denoted by the same reference numerals, and overlapping descriptions may be omitted or simplified.

Embodiment
The configuration of the probe 100 according to the embodiment will be described. FIG. 1 is a schematic cross-sectional side view showing an example of a state at the time of measurement of the probe 100 according to the embodiment. As shown in FIG. 1, the probe 100 according to the embodiment houses the test object of the measurement object inside, and measures the electrical impedance of the test object in a state of being disposed in a predetermined temperature environment. The predetermined temperature is a temperature at which an electrical impedance is required for the measurement object. For example, the predetermined temperature may be a temperature within a temperature range adapted to the intended use of the measurement object.

The probe 100 is disposed in a temperature control device 1 which is a device for forming a predetermined temperature environment. Then, the probe 100 is electrically connected to the impedance measurement device 2 via the cable 3. The temperature control apparatus 1 may be a heating furnace such as an electric furnace that brings the inside into a high temperature state, or may be a cooling furnace such as a refrigerator or a cryostat that brings the inside into a low temperature state. The probe 100 is partially inserted into the temperature control device 1 through the mounting hole 1 a or the like of the temperature control device 1. At this time, the portion of the probe 100 that accommodates the specimen is located in the temperature control device 1. The connection portion of the cable 3 in the probe 100 may be located outside the temperature control device 1. The impedance measuring device 2 applies a voltage to two electrodes (not shown) of the probe 100 and measures the electrical impedance between the two electrodes. The measurement result of the impedance by the impedance measurement device 2 shows the electrical impedance of the sample by the sample being sandwiched between the two electrodes.

Further, referring to FIG. 2, a schematic cross-sectional side view of the probe 100 of FIG. 1 is shown. The probe 100 includes a bottomed cylindrical shield conductor 101, a center conductor 106 extending in the shield conductor 101, and a first holding member 109 for holding the center conductor 106 with respect to the shield conductor 101. Furthermore, the probe 100 includes a probe connector 105 that is detachably connected to the electrical connector 4 of the cable 3 of the impedance measurement device 2. Here, the shield conductor 101 is an example of a first electrode, and the center conductor 106 is an example of a second electrode.

The shield conductor 101 has a hollow structure in which both ends of the cylindrical portion are closed. The shield conductor 101 has a closed space 104 in the inside for accommodating the test object 10 of the measurement object. In the present embodiment, the closed space 104 is a sealed space, but is not limited to this and may not be sealed.

The shield conductor 101 is composed of a first member 102 and a second member 103 which can be connected and separated from each other. Each of the first member 102 and the second member 103 has a bottomed cylindrical shape. The first member 102 and the second member 103 respectively have cylindrical

peripheral walls

102a and 103a and flat

bottom walls

102b and 103b. The cross-sectional shape of the

peripheral walls

102a and 103a is not limited to a circle, and may be any shape such as an ellipse, an oval, or a polygon. Here, the bottom wall 103 b is an example of a first wall, and the

peripheral walls

102 a and 103 a are an example of a second wall.

The first member 102 and the second member 103 can be connected to and separated from each other at the ends of the

peripheral walls

102a and 103a. The first member 102 and the second member 103 form a closed space 104 inside by being connected. The connection structure of the first member 102 and the second member 103 may be any connection structure, for example, a structure connected by screwing or fitting. It is preferable that the connection structure of the first member 102 and the second member 103 be a structure in which the airtightness of the connection portion is maintained. A sealing material may be disposed at the connecting portion to maintain the air tightness. When the probe 100 is used under high temperature, the sealing material preferably has heat resistance.

The probe connector 105 is disposed on the bottom wall 102 b of the first member 102 outside the shield conductor 101. The bottom wall 102 b is electrically connected to the first terminal 105 a of the probe connector 105. The specimen 10 is placed on the bottom wall 103 b of the second member 103 in the shield conductor 101. The specimen 10 is disposed on the bottom wall 103 b with the first member 102 and the second member 103 separated. Thereafter, the test piece 10 is accommodated in the closed space 104 by connecting the first member 102 and the second member 103.

Communication pipes

102 c and 102 d are provided on the peripheral wall 102 a of the first member 102. The

communication pipes

102c and 102d may be integrally formed on the peripheral wall 102a with the same material as the first member 102, and may be configured to be connected to the peripheral wall 102a. The

communication tubes

102 c and 102 d communicate the closed space 104 with the outside of the shield conductor 101. The

communication tubes

102c and 102d are preferably arranged to be located outside the temperature control device 1 when the probe 100 is installed in the temperature control device 1, and for example, are arranged near the bottom wall 102b. Further, valves 102 ca and 102 da are provided in the

communication pipes

102 c and 102 d, respectively. The valves 102ca and 102da are valves that open or close the

communication pipes

102c and 102d, respectively. For example, the valves 102ca and 102da may be on-off valves or non-return valves.

The closed space 104 can be evacuated by drawing the air in the closed space 104 through the communication pipe 102c. In addition, the inert gas 110 is injected into the closed space 104 through the communication pipe 102c, and the air in the closed space 104 is discharged through the communication pipe 102d, whereby the inert gas is inert gas. It can be filled at 110. The inert gas 110 is preferably a gas that does not change its properties even at high temperatures and low temperatures, that is, it has no temperature dependency. In addition, the inert gas 110 is preferably a gas having no dielectricity. Examples of inert gas 110 are helium, nitrogen and argon. Such inert gas 110 is not capacitive and does not change its electrical impedance depending on the volume of the inert gas. The vacuum also has the same properties as the above-mentioned properties of the inert gas.

The vacuum in the enclosed space 104 and the inert gas 110 have good and stable electrical insulation regardless of the temperature change outside the shield conductor 101, and in particular, it is better and more stable than the solid material. Good insulation. In the present embodiment, when measuring the electrical impedance of the specimen 10 by the probe 100, the closed space 104 is evacuated or filled with the inert gas 110.

The first member 102 and the second member 103 are made of a conductive material. When the probe 100 is used under high temperature, the constituent material of the first member 102 and the second member 103 preferably has heat resistance. Examples of constituent materials of the first member 102 and the second member 103 are stainless steel (also referred to as “SUS”), aluminum and an aluminum alloy. The first member 102 and the second member 103 electrically connect the specimen 10 and the first terminal 105 a of the probe connector 105. The shield conductor 101 including the first member 102 and the second member 103 is an example of the first electrode. Although not limited to this, in the present embodiment, the shield conductor 101 is formed in a size of about 10 to 15 mm in inner diameter φ.

The central conductor 106 has a rod-like shape and extends from the bottom wall 102 b toward the bottom wall 103 b in the closed space 104. The central conductor 106 is made of a conductive material. When the probe 100 is used under high temperature, it is preferable that the constituent material of the central conductor 106 have heat resistance. Examples of the constituent material of the central conductor 106 are stainless steel, platinum, aluminum and an aluminum alloy.

The central conductor 106 extends with an air gap between the

peripheral walls

102 a and 103 a and does not contact the shield conductor 101. One end of the central conductor 106 contacts the specimen 10 so as to sandwich the specimen 10 with the bottom wall 103 b. The central conductor 106 is slidably provided in the axial direction of the shield conductor 101 from the bottom wall 102 b toward the bottom wall 103 b with respect to the shield conductor 101. That is, the central conductor 106 is slidable in the direction toward and away from the bottom wall 103 b at one end thereof.

The biasing member 107 is connected to the other end of the central conductor 106. The biasing member 107 is made of a conductive material. The biasing member 107 may be made of the same material as the center conductor 106. Examples of the biasing member 107 are springs such as a coil spring, a conical spring, a bamboo spring, a disc spring, and a ring spring. The biasing member 107 is supported by the insulating member 108 fixed to the bottom wall 102b, and biases the central conductor 106 toward the bottom wall 103b. That is, the biasing member 107 biases the central conductor 106 into contact with the specimen 10 on the bottom wall 103 b. Furthermore, the biasing member 107 causes the center conductor 106 to sandwich the specimen 10 with the bottom wall 103 b.

The insulating member 108 is fixed to the through hole formed in the bottom wall 102 b and electrically insulates the bottom wall 102 b and the biasing member 107. The insulating member 108 is made of an electrically insulating material. Examples of the constituent material of the insulating member 108 are ceramic, alumina (also called "aluminum oxide"), and fluorocarbon resin (also called "fluorocarbon resin", "Teflon (registered trademark)" or "polytetrafluoroethylene") is there. One end of the biasing member 107 is connected to the central conductor 106. The other end of the biasing member 107 is electrically connected to the second terminal 105 b of the probe connector 105 through the through hole 108 a of the insulating member 108. A seal material may be disposed between the through hole 108 a of the insulating member 108 and between the insulating member 108 and the bottom wall 102 b in order to maintain airtightness.

The central conductor 106 and the biasing member 107 electrically connect the specimen 10 and the second terminal 105 b of the probe connector 105. Such central conductor 106 and biasing member 107 are examples of the second electrode. Although not limited to this, in the present embodiment, the center conductor 106 is formed to have a diameter of about 5 mm. The biasing member 107 may be omitted, and the central conductor 106 may be electrically connected to the second terminal 105 b. Further, the biasing member 107 may be made of a material having electrical insulation. In this case, the central conductor 106 may be electrically connected to the second terminal 105 b through a flexible conductive member such as a wire.

In addition, in the closed space 104, a second holding member 107a for holding the position of the central conductor 106 and the biasing member 107 is provided. The second holding member 107 a has a bottomed cylindrical shape, and is disposed on the bottom wall 102 b of the first member 102 or the insulating member 108. The second holding member 107a is made of an electrically insulating material. Examples of the constituent material of the second holding member 107a are ceramic, alumina, and fluorine resin. The second holding member 107a may be made of a conductive material. The second holding member 107a is disposed with the bottom portion facing the bottom wall 103b. The second holding member 107 a houses the biasing member 107 therein, and holds the position of the biasing member 107 in a direction perpendicular to the axial center of the shield conductor 101. The center conductor 106 penetrates the bottom of the second holding member 107a and is connected to the biasing member 107 inside the second holding member 107a. The second holding member 107 a holds the position near the end of the central conductor 106 in the direction perpendicular to the axial center of the shield conductor 101.

The first holding member 109 is disposed in the peripheral wall 102 a through a female screw hole 102 e formed in the peripheral wall 102 a of the first member 102. A plurality of female screw holes 102e are arranged along the circumferential direction of the peripheral wall 102a, and each female screw hole 102e is formed penetrating the peripheral wall 102a. Although not limited to this, in the present embodiment, the plurality of female screw holes 102 e are arranged radially from the axial center of the peripheral wall 102 a. A plurality of first holding members 109 are disposed in each of the plurality of female screw holes 102e.

Referring to FIGS. 2 and 3, although not limited to this, in the present embodiment, three female screw holes 102e are formed, and three first holding members 109 radially from the axial center of peripheral wall 102a. It is arranged. Furthermore, the three first holding members 109 are disposed on the same cross section that is substantially perpendicular to the axial center of the peripheral wall 102a. Further, the three first holding members 109 are arranged at equal intervals in the circumferential direction of the peripheral wall 102a. In addition, the position in the axial center direction of the surrounding wall 102a in the three 1st holding members 109 may differ, and the space | interval of the three 1st holding members 109 may differ.

The first holding member 109 is made of an electrically insulating material. Examples of the constituent material of the first holding member 109 are ceramic, alumina, and fluorocarbon resin. Each first holding member 109 integrally has a shaft portion 109a formed with an external thread, and an engaging portion 109b for screw-rotating the first holding member 109. The shaft portion 109 a of each first holding member 109 is screwed into the female screw hole 102 e and extends from the outside of the shield conductor 101 to the inside. The engaging portion 109 b of each first holding member 109 is located outside the shield conductor 101. The engagement portion 109b is configured to be engaged by a tool, and is rotated so as to screw-rotate the shaft portion 109a by the engaged tool. For example, the engagement portion 109b has a hexagonal nut shape or has a groove of "+" or "-", and is engaged and rotated by a hexagonal wrench or a driver. In addition, although not limited to this, the tip end of the shaft portion 109a has a pointed shape so as to make point contact with the central conductor 106. The tip of the shaft portion 109a may be in line contact with the central conductor 106 or may be in surface contact. As the contact area between the first holding member 109 and the central conductor 106 is smaller, the electrical impedance of the central conductor 106 is less affected by the first holding member 109. In addition, a sealing material for maintaining airtightness may be disposed in the connecting portion between the first holding member 109 shaft portion 109a and the female screw hole 102e. When the probe 100 is used under high temperature, the sealing material preferably has heat resistance.

The first holding member 109 as described above is expanded and contracted from the peripheral wall 102 a so as to advance or retract toward the axial center of the peripheral wall 102 a by screw rotation. By adjusting the amount of protrusion of the three first holding members 109 from the peripheral wall 102a, the first holding member 109 is brought into contact with the central conductor 106 in three directions, and the central conductor 106 is positioned at the axial center of the peripheral wall 102a, that is, at the center. Can be held. The three first holding members 109 may not be in contact with the central conductor 106. In this case, the position of the central conductor 106 is held in the space between the tips of the three first holding members 109. Ru. And adjustment of the expansion-contraction amount of three 1st holding members 109 is possible by the approach from the outer side of the shield conductor 101. FIG.

As shown in FIG. 2, the first holding member 109 is disposed between the specimen 10 and the bottom wall 102 b. The first holding member 109 is preferably disposed at a position close to the specimen 10 in order to suppress positional deviation of the center conductor 106 with respect to the specimen 10. For this reason, the first holding member 109 may be disposed on the peripheral wall 103 a of the second member 103. The first holding member 109 can keep the position of the central conductor 106 even when the first member 102 and the second member 103 are separated by being disposed on the first member 102.

The probe connector 105 is detachably connected to the electrical connector 4 of the cable 3 of the impedance measurement device 2. The cable 3 includes two conductors for transmitting and receiving signals, and the electrical connector 4 includes two terminals electrically connected to the two conductors. When the probe connector 105 is connected to the electrical connector 4, the

terminals

105 a and 105 b of the probe connector 105 are electrically connected to the two terminals of the electrical connector 4 respectively. Thus, a voltage can be applied by the impedance measuring device 2 to the shield conductor 101 and the central conductor 106 sandwiching the specimen 10, and the electrical impedance of the specimen 10 can be measured by the impedance measuring device 2. Although not limited to this, in the present embodiment, the cable 3 is a coaxial cable, and the electrical connector 4 and the probe connector 105 are coaxial connectors.

Next, an example of measurement operation using the probe 100 according to the embodiment will be described. Referring to FIGS. 1 and 2, first, the first member 102 and the second member 103 of the shield conductor 101 are separated. Then, by adjusting the amount of expansion and contraction of the first holding member 109, the position of the center conductor 106 is aligned with, for example, the axial center position of the first member 102. Next, the test body 10 is disposed on the bottom wall 103 b of the second member 103, and the first member 102 is assembled to the second member 103 while bringing the central conductor 106 into contact with the test body 10. At the time of assembly, the central conductor 106 in contact with the test object 10 can slide in accordance with the size of the test object 10, so that breakage of the test object 10 can be suppressed. Furthermore, the center conductor 106 is pressed toward the specimen 10 by the biasing force of the biasing member 107 and maintains contact with the specimen 10. Thus, the specimen 10 contacts the bottom wall 103 b and the central conductor 106.

Furthermore, a pipe is connected to the communication pipe 102 c, air in the closed space 104 of the shield conductor 101 is sucked out, and the closed space 104 is evacuated. Alternatively, an inert gas is injected into the enclosed space 104, and the enclosed space 104 is filled with the inert gas. Thus, the central conductor 106 is electrically isolated from the shield conductor 101 by the vacuum or inert gas present between the central conductor 106 and the shield conductor 101. The valves 102 ca and 102 da maintain the airtightness of the closed space 104 and maintain the vacuum state of the closed space 104 or the filled state of the inert gas.

Then, the shield conductor 101 is partially inserted into the mounting hole 1 a of the temperature control device 1. At this time, the bottom wall 103 b and the first holding member 109 are located inside the temperature control device 1, and the bottom wall 102 b and the

communication pipes

102 c and 102 d are located outside the temperature control device 1. The probe connector 105, the insulating member 108, and the valves 102ca and 102da are not affected by the heat generated by the temperature control device 1, and are present, for example, in an atmosphere at room temperature, so a heat resistant design is unnecessary. In such a probe connector 105 and the insulating member 108, a change in impedance can be suppressed regardless of the temperature change in the temperature control device 1. For example, if the impedance of the probe connector 105 or the insulating member 108 changes due to the high temperature, the probe connector 105 or the insulating member 108 may have an unintended conductivity.

After the shield conductor 101 is inserted, the temperature adjustment device 1 is activated, and the temperature in the temperature adjustment device 1 is adjusted to a predetermined temperature for measuring the electrical impedance of the sample 10. Heat in the temperature control device 1 is transferred to the enclosed space 104 and the specimen 10 through the shield conductor 101. Thereby, the temperature of the specimen 10 rises to a predetermined temperature. Then, the electrical impedance between the shield conductor 101 and the central conductor 106, that is, the electrical impedance of the specimen 10 is measured by the impedance measurement device 2. In the temperature control device 1, the shield conductor 101 and the center conductor 106 continue to be electrically insulated by the vacuum space or the space of the inert gas existing therebetween. The electrical insulation of the vacuum space or the space of the inert gas does not change even when it receives the heat transferred through the shield conductor 101, and maintains good insulation. The electrical impedance of the vacuum space and the space of the inert gas is maintained regardless of the distance between the shield conductor 101 and the center conductor 106 and the heat transmitted through the shield conductor 101, and its value is infinite It is. Thus, the electrical insulation between the shield conductor 101 and the center conductor 106 is reliably and stably maintained. Therefore, accurate measurement of the electrical impedance of the specimen 10 is possible.

As described above, the probe 100 according to the embodiment is a probe for measuring the electrical impedance of the specimen 10. The probe 100 has a hollow cylindrical shield conductor 101 as a first electrode having a closed space 104 for accommodating the specimen 10, and a central conductor 106 as a second electrode extending into the closed space 104 and insulated from the shield conductor 101. And The central conductor 106 extends with an air gap between it and the wall of the shield conductor 101, and sandwiches the specimen 10 with the wall, and the closed space 104 is vacuum or filled with the inert gas 110. It is done.

According to the above configuration, the air gap between the wall of the shield conductor 101 and the center conductor 106 is a vacuum or air gap filled with the inert gas 110. For this reason, regardless of the temperature around the shield conductor 101, the shield conductor 101 and the center conductor 106 are stably insulated by the vacuum or the inert gas 110. Further, regardless of the distance between the shield conductor 101 and the center conductor 106, the shield conductor 101 and the center conductor 106 are stably insulated by vacuum or the inert gas 110. The probe 100 according to such an embodiment can improve the electrical insulation between the electrodes in contact with the specimen 10, that is, between the shield conductor 101 and the center conductor 106.

In addition, the probe 100 according to the embodiment includes the insulating first holding member 109 that holds the central conductor 106 with respect to the shield conductor 101. A wall portion of the shield conductor 101 is a peripheral wall as a second wall portion extending with a gap between the bottom wall 103 b as a first wall portion sandwiching the test body 10 with the central conductor 106 and the central conductor 106. And 102a and 103a. The first holding member 109 extends from the peripheral wall 102 a to the central conductor 106 and holds the central conductor 106 in at least one direction.

According to the above configuration, the center conductor 106 is held by the first holding member 109 from at least one direction from the circumferential wall 102 a toward the center conductor 106. Thereby, since the insulating first holding member 109 can keep the contact area with the central conductor 106 low, the influence exerted on the electrical impedance of the central conductor 106 can be suppressed. As in the embodiment, at least two first holding members 109 may hold the center conductor 106 in at least two directions. As a result, displacement of the central conductor 106 in the radial direction perpendicular to the axial center of the peripheral wall 102 a is suppressed, so that more reliable contact between the central conductor 106 and the specimen 10 is possible.

Further, in the probe 100 according to the embodiment, at least two first holding members 109 are radially arranged from the center conductor 106 to the peripheral wall 102 a of the shield conductor 101. According to the above configuration, the at least two first holding members 109 can hold the center conductor 106 substantially equally and stably from at least two radial directions.

Further, in the probe 100 according to the embodiment, the first holding member 109 can extend and contract from the peripheral wall 102 a of the shield conductor 101. According to the above configuration, the first holding member 109 can adjust the position of the central conductor 106 to a desired position by expanding and contracting.

Further, in the probe 100 according to the embodiment, the center conductor 106 is provided slidably in the direction toward and away from the bottom wall 103 b of the shield conductor 101. According to the above configuration, the central conductor 106 can slide in contact with the specimen 10 in accordance with the size of the specimen 10. Thus, the central conductor 106 is in contact with the test pieces 10 of various sizes to enable measurement of the electrical impedance.

The probe 100 according to the embodiment also includes a biasing member 107 that biases the central conductor 106 toward the bottom wall 103 b of the shield conductor 101. According to the above configuration, by biasing the biasing member 107, the center conductor 106 can maintain contact with the test pieces 10 of various sizes.

Further, the probe 100 according to the embodiment electrically connects each of the shield conductor 101 and the center conductor 106 to the impedance measurement device 2 and is detachably connected to the electrical connector 4 of the impedance measurement device 2. 105 is provided. According to the above configuration, the probe 100 can be treated as a single device in a state separated from the impedance measurement device 2. And, if the electrical connector 4 and the probe connector 105 are common, it is possible to measure the electrical impedance of the sample using the same impedance measuring device 2 even if the size, shape, etc. of the probe 100 are different. is there. Furthermore, by using the probe connector 105, connection and disconnection between the probe 100 and the impedance measurement device 2 can be facilitated.

[Others]
As mentioned above, although the probe concerning the present invention was explained, the present invention is not limited to the above-mentioned embodiment. Without departing from the spirit of the present invention, various modifications that can be conceived by those skilled in the art may be applied to the present embodiment, or an embodiment configured by combining components of different embodiments and modifications may be one of the present invention. Or you may be included in the range of several aspect. For example, the following cases are also included in the present invention.

For example, in the probe 100 according to the embodiment, the three first holding members 109 hold the center conductor 106. However, the number of first holding members 109 is not limited to this, and may be at least one. For example, one first holding member may hold the center conductor 106. In this case, the tip end portion of the shaft portion of the first holding member may be shaped so as to surround the center conductor 106 from the outside. For example, the tip portion may have a circular, elliptical or polygonal through hole, and the central conductor 106 may be disposed through the through hole. In this case, in order to allow screw rotation of the shaft portion of the first holding member, the shaft portion and the tip portion may be configured to be relatively rotatable. The tip portion may be configured to continuously surround the through hole, or may be configured to partially surround the through hole. When the through-hole of such a tip portion has a cross section larger than the cross section of the central conductor 106, it contacts the central conductor 106 in one direction, and supports the central conductor 106 in one direction. Further, the first holding member as described above may be a plate-like member extending in a direction intersecting the axial centers of the

peripheral walls

102 a and 102 b of the shield conductor 101 instead of the shape having the shaft portion. The plate-like member may be fixed to the

peripheral wall

102a or 103a and may further have a through hole through which the central conductor 106 passes. For example, the plate-like member may be an annular plate having an edge along the inner circumferential surface of the

peripheral wall

102a or 103a.

Or, for example, as shown in FIG. 4, two first holding

members

109 and 209 may hold the center conductor 106. 4 is a schematic cross-sectional view showing a probe according to a modification of the embodiment in the same manner as FIG. In the example of FIG. 4, the first holding

members

109 and 209 are radially arranged around the axial center of the peripheral wall 102 a of the shield conductor 101, that is, around the central conductor 106. Specifically, the first holding

members

109 and 209 are arranged in a straight line.

The first holding member 109 is the same as the first holding member of the embodiment. Like the first holding member 109, the first holding member 209 has a shaft portion 109a and an engagement portion 109b, and further has two legs 209c integrally at the tip of the shaft portion 109a. . In the example of FIG. 4, the two legs 209 c form a V-shaped cross section which becomes wider as it is separated from the shaft 109 a. Each leg 209 c may have a bar-like shape or a plate-like shape. The central conductor 106 is engaged and held in each leg 209c between the two legs 209c. Therefore, the center conductor 106 is held at three places by the tip end of the shaft portion 109 a of the first holding member 109 and the two legs 209 c of the first holding member 209.

For example, in the probe 100 according to the embodiment, the first holding member 109 is screwed to the peripheral wall 102 a of the shield conductor 101 and moved so as to expand and contract from the peripheral wall 102 a by screw rotation. The configuration for moving the first holding member 109 may be any configuration. For example, the first holding member 109 may be provided slidably with respect to the peripheral wall 102a, and may be biased toward the axial center of the peripheral wall 102a by a biasing member such as a spring. The biasing member may be disposed inside or outside of the shield conductor 101.

For example, in the probe 100 according to the embodiment, the first holding member is not limited to the configuration having the shaft portion 109a. The first holding member may be configured to extend from the peripheral wall 102 a of the shield conductor 101 to the central conductor 106 and to hold the central conductor 106 in at least one direction. For example, the first holding member may be a plate-like member or a tubular member.

The present invention is applicable to an apparatus for measuring the electrical impedance of a specimen under various temperature environments.

DESCRIPTION OF SYMBOLS 1 Temperature control apparatus 2 Impedance measuring apparatus 4 Electric connector 10 Test object 100 Probe 101 Shield conductor (1st electrode)
102a Peripheral wall (second wall)
103a Peripheral wall (second wall)
103b bottom wall (first wall)
104 enclosed space 105 probe connector 106 central conductor (second electrode)
107 biasing

member

109, 209 first holding member 110 inert gas

Claims

A probe for measuring the electrical impedance of a specimen,
A hollow first electrode having a closed space for accommodating a test object;
A second electrode extending into the enclosed space and insulated from the first electrode;
The second electrode extends with an air gap between the second electrode and the wall of the first electrode, and holds the sample between the second electrode and the wall.
The closed space is a vacuum or filled with an inert gas probe.
It further comprises an insulating holding member for holding the second electrode with respect to the first electrode,
The wall portion includes a first wall portion sandwiching the specimen with the second electrode, and a second wall portion extending across the air gap between the second electrode and the second electrode.
The probe according to claim 1, wherein the holding member extends from the second wall to the second electrode and holds the second electrode in at least one direction.
The probe according to claim 2, wherein at least two of the holding members are arranged radially from the second electrode toward the second wall.
The probe according to claim 2, wherein the holding member is extendable and contractible from the second wall portion.
The probe according to any one of claims 1 to 4, wherein the second electrode is provided slidably in a direction toward and away from the first wall.
The probe according to claim 5, further comprising a biasing member that biases the second electrode toward the first wall.
The probe connector which electrically connects each of the first electrode and the second electrode to an impedance measuring device and is detachably connected to an electrical connector of the impedance measuring device is further provided. The probe according to one item.