JPH087247B2 - Electric resistance measurement method - Google Patents

Description

The present invention relates to an electric resistance measuring method for measuring the electric resistance of pipes, rolls and the like.

[Conventional technology]

Generally, when measuring the electric resistance of a cylindrical object to be measured such as a conductive pipe or roll, an electrode 11 made of Ag paste is provided at a predetermined position on the outer peripheral surface of the object to be measured 10 as shown in FIG. Applying, a DC voltage source 13 is provided between the electrode 11 and the rotating shaft 12 of the DUT 10, and an ammeter 14 is provided in the current path to measure the current, and the applied voltage and the measured current are The electric resistance of the above-mentioned measuring point is measured by the ratio of However, in the case of measuring the electric resistance of the entire outer peripheral surface of the DUT 10 in this way, it is necessary to apply Ag paste and measure the electric resistance all over the outer peripheral surface of the DUT 10. This makes the work extremely complicated. In addition, since the Ag paste is applied to the outer peripheral surface of the object to be measured 10 in the above method, there is a problem that the object to be measured 10 is soiled or damaged. Therefore, instead of using the above contact method of applying Ag paste to the DUT 10, the charge is measured from the corotron.
A non-contact method has been proposed in which the electric resistance is measured based on a table prepared in advance by irradiating 10 and the residual charge remaining on the surface after irradiation. According to this method, it is not necessary to apply an electrode made of Ag paste as described above, and it is possible to easily measure the electric resistance of the entire outer peripheral surface of the measured object. However, what can be measured by this corotron method is an electric resistance of 2 × 10 ⁷ Ω or more, and those with an electric resistance of less than this value have almost no residual charge after irradiation with electric charges from the corotron. It is impossible to measure from. Therefore, for the object to be measured having a small electric resistance, the electrode made of Ag paste has to be applied as described above, but this has various disadvantages as described above.

[Problems to be Solved by the Invention]

As described above, in the conventional electrical resistance measuring method, it is the actual situation that it is not possible to easily measure those having a small electrical resistance.

The present invention has been made in view of such circumstances, and an object thereof is to provide a measuring method capable of easily measuring the electric resistance of the entire outer peripheral surface of a measured object having a small electric resistance.

[Means for solving the problem]

In order to achieve the above-mentioned object, the present invention provides a plurality of electrodes having a contact surface formed in a curved surface along the outer peripheral surface of the cylindrical object to be measured along the axial direction of the cylindrical object to be measured, A cylindrical object to be measured is detachably arranged on the plurality of electrodes arranged in a line with the axial direction aligned, and in that state, a predetermined electrode of the plurality of electrodes and a cylindrical object to be measured are By measuring the electrical resistance of the portion of the cylindrical object to be measured that is in contact with the predetermined electrode by applying a voltage between the electrodes, by performing this sequentially for each electrode along the axial direction of the outer peripheral surface of the cylindrical object. By measuring the electrical resistance of a region of a predetermined width by rotating the cylindrical DUT by a predetermined width in the circumferential direction, the electrical resistance of the entire outer peripheral surface of the cylindrical DUT is measured. The main point is the resistance measurement method.

[Action]

According to the present invention, the cylindrical object to be measured is detachably arranged on the electrodes arranged in a plurality along the longitudinal direction of the base,
In that state, a voltage is applied between a predetermined electrode of the plurality of electrodes and the cylindrical DUT to measure the electric resistance of the portion of the DUT that is in contact with the predetermined electrode. The electrical resistance of a region of a predetermined width is measured along the axial direction of the outer peripheral surface of the cylindrical DUT by sequentially performing the rotation, and then the cylindrical DUT is rotated by a predetermined width in the circumferential direction, in the same manner as above. The electric resistance of the entire outer peripheral surface of the cylindrical object to be measured is measured by repeating the measurement of the electric resistance of a region of a predetermined width along the width direction on the outer peripheral surface of the cylindrical object to be measured. Therefore, the Ag on the outer peripheral surface of the measured object
A complicated work such as applying an electrode made of a paste is not required, and the electric resistance of the entire outer peripheral surface of the measured object can be easily measured.

 Next, examples will be described.

〔Example〕

FIG. 1 is a schematic configuration diagram of an apparatus used in one embodiment of the present invention. In the figure, 1,1 'are a pair of upper and lower bases, and these bases 1,1' are formed in a flat plate shape extending in a direction perpendicular to the plane of the paper.
As shown in (b), a V-shaped groove 2,
2'is formed. On one wall surface 2a of the V-shaped groove 2, 2 ', a plurality of electrodes are arranged in rows along the longitudinal direction at predetermined intervals. Further, a plurality of electrodes p6 to 9 are arranged in a row on the other groove wall surface 2b so as to be located between the electrodes p1 to 5 of the one groove wall surface 2a. These electrodes p1-9 are
As shown in FIG. 2B, the surface thereof is formed into a curved surface along the outer circumference of the cylindrical DUT 3 (see FIG. 1).
As shown in FIG. 3, these electrodes p1 to p9 are vertically arranged via a spring 5 in which a resin base 4 is provided in a concave portion provided in a wooden base. . As shown in FIG. 4, these electrodes p1 to p9 have a lower part made of metal and an upper part made of conductive rubber. In FIG. 3, reference numeral 6 denotes a lead wire, which extends from the electrodes p1 to p9 via a spring 5. This lead wire 6 is, as shown in FIG.
Each extends to the electrode selection switch 7. The switch 7 can select any electrode by operating the knob 7a. The switch 7 knob 7a
And a rotary shaft 3a of the cylindrical DUT 3 between the voltage source 8a
A current path 9 including an ammeter 8b is formed, and a voltage is applied between the electrode selected by the knob 7a and the rotary shaft 3a. The cylindrical object to be measured 3
Is composed of a conductive roll as shown in FIG. 7, and its outer peripheral surface and the rotating shaft 3a are electrically connected.

In this state, operate the knob 7a, apply the above voltage between any of the electrodes and the rotating shaft 3a, examine the current flowing at that time with an ammeter, Is applied, the resistance R of the outer peripheral surface portion of the DUT 3 in contact with the electrode is obtained. In this case, since the voltage V is constant, the resistance R can be easily obtained from the current value I. In this way, when measuring the electric resistance of the outer peripheral surface of the cylindrical DUT 3, for example,
The length l of the electrodes p1 to 9 arranged in the axial direction shown in FIG. 2 (a) is adjusted to the length l of the cylindrical roll shown in FIG. 7, and the width m of the electrodes p1 to 9 (fourth (See the figure) is set to 1/10 of the length of the outer circumference of the cylindrical DUT 3. In the apparatus shown in FIG. 1 set in this way, the electrodes p1 to 5 of one groove wall surface 2a of the upper base 1'are operated sequentially, the electric resistance of the portion in contact therewith is measured, and the other groove is then measured. Wall 2b electrode
Similarly, p6 to 9 are operated, and the electric resistance of the portion in contact with it is measured. Next, for the lower base 1 as well, the respective electrodes p1 to p9 are actuated in the same manner as above, and the electrical resistance is measured. In this case, on the upper base 1 ', one groove wall surface
Between the plurality of electrodes p1 to 5 of 2a, the electrode p6 of the other groove wall surface 2b
Assuming that the electrodes p1 to p9 are made into a single straight line by inserting ~ 9 into the electrodes, the electrodes of the upper base 1'can be obtained by the above series of measurement operations.
In p1 to 9, the electric resistance was measured with a width of m along the outer peripheral surface of the cylindrical DUT 3 along the axial direction. At the same time, the electrical resistances of the electrodes p1 to 9 of the lower base 1 are also measured at m along the outer peripheral surface of the cylindrical DUT 3 along the axial direction.
That is, the electrical resistance of the outer peripheral surface of the cylindrical object to be measured 3 is measured with a width of 2 m along the axial direction by the series of measurement operations described above. Therefore, after the series of measurement operations described above is completed, the cylindrical object 3 is displaced in the circumferential direction by a predetermined width (width of m), and the series of measurement operations similar to the above is repeated to obtain a cylindrical shape. The electrical resistance is measured with a width of 2 m along the outer peripheral surface of the DUT 3 along the axial direction. By repeating such a series of operations five times, the electric resistance of the entire outer peripheral surface of the cylindrical DUT 3 is measured. The electrical resistance R of the electrodes p1 to p9 in this case is schematically shown in FIG.

FIG. 6 shows that the personal computer and the step motor are incorporated in the apparatus shown in FIG. 1, and the personal computer is operated to drive the step motor to rotate the cylindrical object to be measured 3 by a predetermined angle and operate each electrode in that state. Sequentially measure the electrical resistance,
After this value is stored in the personal computer, the same operation as described above is automatically repeated to automatically measure the electric resistance of the entire outer peripheral surface of the cylindrical DUT 3.

In the above description, the conductive roll shown in FIG. 7 is taken as an example of the cylindrical object to be measured, but the present invention is not limited to this, and a conductive pipe or the like can be used for measurement. . Therefore, the cylindrical object to be measured in the present invention includes not only a pipe-shaped object but also a roll-shaped object, and the roll may be hollow or solid. .

〔The invention's effect〕

As described above, according to the present invention, a base having a plurality of electrodes having contact surfaces formed on a curved surface along the outer peripheral surface of the cylindrical object to be measured is provided along the axial direction of the cylindrical object to be measured. Using the above-mentioned plurality of electrodes, the cylindrical DUT is arranged in a detachable manner by aligning the axial direction, and in that state, a voltage is applied between a predetermined electrode of the plurality of electrodes and the cylindrical DUT. By sequentially performing the measurement of the electrical resistance of the portion of the cylindrical object to be measured that is in contact with the predetermined electrode by applying each electrode, a region of a predetermined width along the axial direction of the outer peripheral surface of the cylindrical object to be measured is measured. Measure the electrical resistance. Then, after this measurement, the cylindrical object is rotated in the circumferential direction by a predetermined width, and the above measurement is repeated. By repeating such an operation, the electric resistance of the entire outer peripheral surface of the cylindrical object to be measured can be measured. Therefore, it does not require the complicated work of applying electrodes made of Ag paste to the outer peripheral surface of the object to be measured as in the past, and the cylindrical object to be measured has a small electric resistance that cannot be measured by the corotron method. It becomes possible to measure the electric resistance of the entire outer peripheral surface.

[Brief description of drawings]

FIG. 1 is an explanatory view showing the configuration of an embodiment of the present invention, FIG. 2 (a) is a plan view of its base, FIG. 2 (b) is its side view, and FIG. 3 is FIG. b) Enlarged cross-sectional view of the circled portion A, FIG. 4 is an enlarged perspective view of the electrode portion, FIG. 5 is a conceptual diagram of electric resistance measurement at each electrode, and FIG. 6 is the apparatus of FIG. FIG. 7 is an explanatory view of an example in which the above is automated, and FIG. 1,1 '... Base, 2, 2' ... V-shaped groove, 3 ... Cylindrical object to be measured, 3a ... Rotation axis, p1 to p9 ... Electrode, 6 ... Lead wire, 7 ... … Electrode selection switch, 7a …… Knob, 8a ……
Voltmeter, 8b ... Ammeter, 9 ... Current path

Claims (1)

[Claims] 1. A plurality of electrodes, each having a contact surface formed on a curved surface along the outer peripheral surface of a cylindrical object to be measured, are arranged in a line along the axial direction of the cylindrical object to be measured, Place the cylindrical object to be measured on the electrode so that it can be attached and detached with the axial direction aligned,
In that state, by measuring the electric resistance of the portion of the cylindrical object to be measured in contact with the predetermined electrode by applying a voltage between a predetermined electrode of the plurality of electrodes and the cylindrical object to be measured, To measure the electrical resistance of a region of a predetermined width along the axial direction of the outer peripheral surface of the cylindrical measured object by sequentially performing for each electrode, rotate the cylindrical measured object by a predetermined width in the circumferential direction. The electric resistance measuring method is characterized by measuring the electric resistance of the entire outer peripheral surface of the cylindrical object to be measured.