JPS5957102A - Apparatus for measuring dimension - Google Patents

Abstract

PURPOSE:To enable the accurate measurement of the dimension of an object to be inspected, by providing an electrostatic capacity measuring means for measuring electrostatic capacity while applying high frequency between a pair of electrodes and a dimension converting means for converting the measured electrostatic capacity to the dimension of the object to be inspected. CONSTITUTION:An object 25 to be inspected is held between a measuring stand 20 and a measuring element 21 and oscillation frequency at this time is inputted to a microcomputer 33 as M1 to be stored. In the microcomputer 33, said oscillation frequency M1 is put in the relation of preliminarily set oscillation frequency and the dimension of the object 25 to be inspected and the dimension M2 of the object 25 to be inspected is stored. Said dimension is displayed by a display apparatus 35 through a driver circuit 34. In the next step, hair is removed and a display part 24 is adjusted so as to display 0mum in such a state that no object is present between the measuring stand 20 and the measuring element 21. As the result, the dimension of hair, a wire material or a film can be easily and accurately measured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on the size (
The present invention relates to a dimension measuring device that measures dimensions (such as thickness and thickness), and particularly relates to a dimension measuring device that can easily and accurately measure the dimensions of a subject.

In the present invention, a pair of electrodes (for example, a signal electrode and a ground electrode) that are previously separated by a certain distance are further separated according to the dimensions of a subject, and a high frequency is applied between the pair of electrodes to separate the pair of electrodes. The capacitance between the two is measured, and the capacitance is converted into the dimension of the object to be measured.

In the above case, if the circuit constant is constant, a certain correlation will be established between the capacitance and the oscillation frequency, so the oscillation frequency corresponding to the capacitance at this time will be measured. For example, if all conditions such as electrode area 2 circuit constants are kept constant, there is a difference between this oscillation frequency and the dimensions of the object.
Since the relationship shown in the figure holds true, the dimensions of the object can be determined from the measured oscillation frequency.

However, when nothing is sandwiched between the measuring table and the measuring head (θμ
7n), if the distance between the pair of electrodes deviates from the normal state, the measurement result of "0 μm" will naturally not be obtained. If you directly measure the dimensions of the object, you will get an incorrect measurement result. It will be done. Therefore, in the present invention, by adjusting the position of the measuring table at 1 o'clock when there is nothing between the measuring table and the measuring head, the display of "08m71" is displayed.
This allows for θ point calibration.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a case where an embodiment of the dimension measuring device of the present invention is used to measure the diameter of a hair will be described with reference to the drawings. Fig. 1 shows the outline of the structure of the hair diameter measuring device of the present invention, and Fig. 2 shows the outline of the main parts of the hair diameter measuring device of the present invention when viewed from the front. It is something. In the figure, 1 is a measuring knob that moves the shaft 18 up and down, 2 is a rotation stopper for the probe 21, 3 is the main body, 4 is a bearing, 5 is a ground electrode, 6 is a signal electrode, 7 is a spacer made of electrical insulation material, 8 and 15 are bolts for fixing the control circuit 11;
are DC lines and signal lines, 10 and 14 are spacers, 12 is a bolt made of electrical insulating material provided to fix the signal electrode 6 to the electrode fixing plate X6, and ! 3 is a shield case,
I7 is a signal line of a signal electrode, and 19 is a bearing. 20
is a measuring table whose lower ends are screwed together, so it can be moved up and down by rotating it to the left or right. 2
2 is the outer box, 23 is the AC power supply 0N10FF switch, 2
4 is a display section, and 25 is a subject.

FIG. 3 is a block diagram showing an electronic control circuit using a microcomputer of the hair diameter measuring device according to the present invention, including a 33G microcomputer, 26 an AC power supply, 27 a DC power supply circuit, and 28 a microcomputer. Reference pulse oscillator, 2
9 is a frequency counter, 30 is a -1 electrode (signal electrode 6 and ground electrode 5), and 31 is a CR oscillation circuit (one end of the signal line 17 of the signal electrode 6 is connected to the signal side G of the CR oscillation circuit). , and the ground electrode 5 is connected to the ground side of the CR oscillation circuit σ], 32 is the oscillation circuit,
34 is a driver circuit, and 35 is a display device.

Next, the function of the hair diameter measuring device of the present invention will be explained using G tips I and Z.

First, turn on the 0N10FF switch 23 of the AC power supply.
Make it. Next, with nothing sandwiched between the measuring stand 20 and the measuring head 2I (calibration state...0 μm), rotate the measuring stand 20 to adjust the distance between the signal electrode 6 and the ground electrode 5. The display on the display unit 24 is [0]μ27. Tona Gensunsuru.

Next, a single hair of the subject 25 is placed between the measuring table 20 and the measuring element 21 as shown in FIG. The oscillation frequency at this time is input to the microcomputer 33 and stored as Ml. The microcomputer 33 enters the current oscillation frequency M1 into a predetermined relationship between the oscillation frequency and the dimensions of the object (for example, the relationship in the example shown in FIG. 5), calculates the object dimension M2, and stores it in memory. The dimensions are displayed on the display section 24 of the display device 35 via the driver circuit 34. (For example l-
80jμη2 is displayed. ) Next, when the hair of the subject 25 is removed, the measurement table 2
Since there is nothing between 0 and the probe 2I, "0" μm should be displayed on the display section 24, but if there is a deviation, adjust as described above. Thereafter, the diameter of the hair, which is the subject 25, is measured in the same manner as described above. Such a relationship is shown in the flowchart of FIG.

Since the one-method measuring device of the present invention has the above configuration,
0 μ? by moving the position of the measuring table appropriately. +1 calibration can be performed on hair and wire rods.

The dimensions (thickness, thickness, etc.) of films, etc. can be easily and accurately measured.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an embodiment of the dimension measuring device of the present invention, FIG. 2 is a schematic diagram of FIG. 1 seen from the front, and FIG. 3 is an electronic diagram of an embodiment of the dimension measuring device of the present invention. FIG. 4 is a block diagram of the control circuit, FIG. 4 is a flowchart showing the operation of an embodiment of the dimension measuring apparatus of the present invention, and FIG. 5 is a diagram showing the relationship between the dimensions of the object and the oscillation frequency. In the drawing, 5 is a ground electrode, 6 is a signal electrode, 20 is a measuring table, 21 is a measuring element, and 25 is a subject.

Claims (1)

[Claims] 1. Inter-electrode distance changing means for changing the distance between a pair of electrodes according to the distance between the measuring table and the measuring head that sandwich the object, and applying a high frequency between the pair of electrodes changed by the inter-electrode distance changing means. a capacitance measuring means for measuring capacitance, a dimension converting means for converting the capacitance measured by the capacitance measuring means into dimensions of the object, and a measuring table for the interelectrode distance changing means. A dimension measuring device comprising: a calibration means for performing zero μm calibration by appropriately moving the position of the dimension measuring device.