JPH0223807B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an apparatus for measuring the thickness of an insulator, and particularly to an apparatus for measuring the thickness of rolled rubber on a metal roll.

[Conventional technology]

Conventionally, as a thickness measuring device for insulators, the
Like the device shown in Publication No. 58-103601, a combination of an eddy current sensor and an electrostatic sensor or an eddy current sensor and an optical sensor is used to detect the difference in the distance from the device to the conductor surface and the distance from the device to the insulator. A device has been proposed that measures the thickness of an insulator by determining .

[Problem to be solved by the invention]

The thickness measuring device is a compact and portable device that makes it possible to accurately measure, without contact, the thickness of an insulator on a conductor surface, especially the thickness of rolled rubber on a metal roll in a rubber rolling process. It is. However, the aforementioned optical sensors and electrostatic sensors require correction before measurement due to temperature drift, differences in characteristics due to composition, etc., and this correction requires correction of each sensor because the difference in absolute amount of each sensor is taken as the thickness. The problem is that the full range of characteristics must be investigated before measurement, which requires a lot of effort.

The purpose of this invention is to measure the distance from the device to the surface of the conductor and the distance from the device to the insulator using two types of sensors, and to measure the thickness of the insulating material by measuring the distance from the device to the surface of the conductor and the distance from the device to the insulating material. To provide an excellent insulator thickness measuring device that allows the output characteristics of sensors to be easily examined and that allows each sensor to be calibrated accurately and extremely easily in a short period of time.

[Means to solve the problem]

To achieve the above object, the insulation thickness measuring device of the present invention includes an insulator sensor and an eddy current sensor that measure the distance to the insulator on the conductor, and the distance measured by the two types of sensors. The thickness measuring device measures the thickness of the insulating material from the difference between When the point measuring means is selected, the zero point measuring means for storing zero point output values for the two types of sensors is activated, and when the gain measuring means is selected, the moving mechanism is activated,
gain measuring means for measuring the output before and after the movement of each of the two types of sensors, calculating and storing a gain from the difference between the measured values and the movement distance;
and correction means for performing zero point correction and gain correction on the respective measured values of the two types of sensors.

〔Example〕

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

FIG. 1 is a block diagram illustrating the outline of the insulator thickness measuring device of the present invention, and FIGS. 2 and 3 show specific embodiments.

In these figures, 1 and 2 are sensors that measure the distance to the surface of the conductor M and sensors that measure the distance to the insulator R, respectively.For example, sensor 2
An electrostatic sensor or an optical sensor is used for
An eddy current sensor is used as the sensor 1. The sensors 1 and 2 are attached to a base 3, and the base 3 is moved by a predetermined distance α in the direction of arrow AA′ by a movement mechanism using an actuator 4 and a slider bearing 7.
(for example, 1 mm). The amount of movement of this base 3 is determined by a limit switch 6 that detects the output limit and a limit switch 5 that detects the return limit.
more accurately.

In addition, the output lines 8 and 9 of the sensors 1 and 2 are connected to the arithmetic unit 10 via interlocking changeover switches 11 and 12, and the remaining contacts of the changeover switches are connected to the rehabilitation circuit 2.
Connected to 0. (The output lines 8, 9, the changeover switches 11, 12, and the correction circuit 20 are not shown in FIGS. 2 and 3.) The limit switches 5, 6
is connected to this correction circuit 20, and the correction circuit 2
0 controls the actuator 4 by the outputs of the limit switches 5 and 6.

Then, when correcting sensors 1 and 2,
The contacts c-b of the changeover switches 11 and 12 are connected so that the outputs of the sensors 1 and 2 are input to the correction circuit 20, and the moving mechanism consisting of the actuator 4, the slide bearing 7, and the limit switches 5 and 6 is operated. The correction values for sensors 1 and 2 are determined. The sensor 1 determined by the correction circuit 20,
2 is input to the calculation device 10, so if the contacts c-a of the changeover switches 11 and 12 are connected, the calculation device 10 will detect the distance on the conductor M based on the distance measurement values from the sensors 1 and 2. The thickness of the insulator R is detected, and this is digitally converted to display the thickness of the insulator R on the display 15 using, for example, digital numbers.
The changeover switches 11 and 12 constitute the selection means of this embodiment.

The configuration and functions of the device of the present invention are as described above. Next, the flowchart in FIG. Explain using.

(1) Measurement of the zero point Since the measured values of the distances from the sensors 1 and 2 to the conductor M and the insulator R are output as voltage, first measure the reference voltage value (zero point voltage). This zero point voltage is defined as the output voltage V _0A of the sensor 1 and the output voltage V _0B of the sensor 2 in a state where there is no insulator R on the conductor M. Later, the value obtained by subtracting this zero point voltage from the output voltages V _A and V _B during measurement by sensors 1 and 2 is used as a voltage corresponding to the distance from the zero point to the measurement point. This procedure is indicated in FIG. 4 by the steps →→→→. That is, the above steps constitute the zero point measuring means of this embodiment.

(2) Sensor gain measurement Output characteristics (gain) during measurement of sensors 1 and 2
In order to examine
move it. The actuator 4 is operated to move the base 3 to the conductor side (step), and when the limit switch 6 is turned on (YES in step), the output voltage of sensors 1 and 2 is changed.
Measure V _2A and V _2B (step), then release the actuator 4 (step), and release the base 3.
When sensor 1 reaches its return limit and limit switch 5 is turned on (YES in step), sensor 1,
Measure the output voltages V _1A and V _1B of 2 (step). Then move on to the step, sensors 1 and 2.
The correction circuit 20 calculates the gain of . Assuming that the gains of the distance-output voltage characteristics of sensors 1 and 2 are K _A and K _B , respectively, K _A and K _B are expressed by the following equations.

K _A = α/V _2A −V _1A , K _B = α/V _2B −V _1B If the object to be measured is a rubber sheet on a roll, this correction should be performed with the roll stopped rotating and in a stationary state. shall be. That is, the gain measuring means of this embodiment was constructed by the above steps.

(3) Measurement of the thickness of the insulator As described above, the zero point voltage of sensors 1 and 2 is measured.
Once V _0A , V _0B and the gains K _A , K _B are determined, the process moves from step to step, and the voltage values V _A , corresponding to the distance to the surface of the conductor M at the sensor 1 are determined.
The sensor 2 simultaneously measures a voltage value V _B corresponding to the distance to the surface of the insulator R. In the step, the aforementioned zero point voltage is subtracted from these measured values, and the distance L _A from the zero point to the surface of the conductor M is calculated.
and the distance from the zero point to the surface of insulator R
Calculate L _B using the gain obtained in the step. That is, the above steps constitute the correction means of this embodiment.

L _A = K _A (V _A - V _0A ) = α/V _2A - V _1A (V _A - V _0A ) L _B = K _B (V _B - V _0B ) = α/V _2B - V _1B (V _B -V _0B ) From these distances L _{A and} L _B , the thickness L of the insulator R on the conductor M is determined by L=L _B -L _A in step.

In addition, when measuring the thickness of the rubber sheet on the sheet output roll, the roll corresponding to the conductor M,
The rubber sheet corresponding to the insulator R rotates eccentrically, and this eccentricity changes the conductor M with respect to the zero point,
This appears as a change in the surface position of the insulator R,
In the device of the present invention, the distances of the conductor M and the insulator R from the zero point are determined, and the thickness of the insulator R is determined by taking the difference between them, so the thickness of the rubber sheet on the roll can be continuously measured. can do. In this case, step →
The steps →→→→ will be repeated. If the answer to step is YES, the measurement ends.

In the apparatus of the present invention, the zero point measurement described in (1) and the sensor gain measurement described in (2) can be performed at any time before the measurement or after interrupting the measurement, as necessary. Moreover, since the correction can be automatically performed using a calculation device and a correction circuit, anyone can easily perform this correction.
Very convenient.

〔Effect of the invention〕

As explained above, the insulator thickness measuring device of the present invention is a device that non-contactly measures the thickness of the insulator on the surface of a conductor, and measures the distance from the device to the conductor surface and the distance to the insulator, respectively. Measure 2
It also has a mechanism for moving the device a known distance in the direction of the conductor surface, and a circuit for checking the output characteristics of each sensor based on the output of each sensor when the device is moved a known distance. Since each sensor can be automatically calibrated within the device before measurement, or after interrupting measurement,
It is possible to calibrate each sensor accurately and extremely easily in a short period of time, which has the effect of shortening measurement time and improving measurement accuracy.

[Brief explanation of drawings]

Fig. 1 is a block diagram illustrating the outline of the insulating material thickness measuring device of the present invention, Figs. 2 and 3 are side and front views respectively showing an embodiment of the same measuring device, and Fig. 4 is the same device. 2 is a flowchart showing a measurement procedure. 1...Eddy current sensor, 2...Insulator sensor, 4...
... Actuator, 5, 6 ... Limit switch, 10 ... Arithmetic device, 20 ... Correction circuit.

Claims (1)

[Scope of Claims] 1. A device comprising an insulator sensor and an eddy current sensor that measure the distance to an insulator on a conductor, and a thickness that measures the thickness of the insulator from the difference in the distance measured by the two types of sensors. The measuring device is provided with a moving mechanism for moving the two types of sensors by a known distance, and a selection unit for zero point measuring means and gain measuring means, and when the zero point measuring means is selected, the two types of sensors are selected. When the zero point measuring means for storing the zero point output value for the two sensors is activated and the gain measuring means is selected, the moving mechanism is activated and the output before and after the movement is measured for each of the two types of sensors. and a gain measuring means for calculating and storing a gain from the difference between the measured values and the travel distance, and a correction means for performing zero point correction and gain correction for each of the measured values of the two types of sensors. Insulator thickness measuring device.