JPH02201202A - Clearance measurement using pressure sensitive paper - Google Patents

Abstract

PURPOSE:To enable measurement of a clearance value between parts quantitatively and at a high accuracy by reading a density level in color formation of a pressure sensitive paper placed between the parts to determine the clearance value. CONSTITUTION:For example, a pressure sensitive paper is made up of two sheets of paper 1 and 2 formed respectively in three layers and one of the paper 1 comprises a microcapsule which contains a support 1a, an intermediate layer 1b and a color forming agent and the other paper 2 is coated with a color developing agent 2a in stead of the microcapsule 1c. Then, when the microcapsule 1c of the paper 1 is broken by a pressure, the color forming agent is adsorbed by the color developing agent 2a of the other paper 2 and a chemical reaction is caused to form a color. Then, a density level of the color formation is converted into a clearance value between objects to be measured using a relationship chart between the density of color formation ad the clearance value prepared beforehand.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for measuring gaps between parts, and more particularly to a method for measuring the amount of gaps created between mating surfaces of assembled parts.

[Prior Art] Conventionally, the following method has been used as a means for measuring the gap between mating surfaces of assembled parts.

(1) Measure the shape of the silk mating surfaces individually and estimate the gap when assembled from each measurement result.

(2) Apply red lead or a pigment commonly called Aotake dissolved in oil evenly and thinly to one of the mating surfaces on which you want to measure the gap, bring the mating surfaces into close contact with each other, and then The amount of gaps is determined and evaluated based on the density of the attached pigment.

[Problems to be Solved by the Invention] However, the conventional gap measurement method has the following problems.

(1) In the method of measuring the shape of a combined surface individually, it is difficult to capture the shape of the single surface three-dimensionally, and it is even more difficult to estimate the gap when the combined surfaces are combined.

(2) The method of measuring by transferring the M material causes variations in the pigment film thickness depending on the amount of oil added to the pigment used and the method of application, and the pressing force used during assembly also varies depending on the operator. , it is easy to cause variations in the judgment of the amount of gap, and since the numerical value of the amount of gap is a sensory evaluation performed based on the experience and intuition of the operator, the values vary widely even among the same number of workers, and manual work is difficult. Therefore, quantitative evaluation is not possible.

The present invention focuses on the above-mentioned conventional problems, and aims to provide a highly accurate quantitative measurement method that eliminates human work and human judgment.

[! ! Means for Solving the Problem] In order to achieve the above object, the gap measurement method using pressure-sensitive paper according to the present invention involves sandwiching pressure-sensitive paper that develops color when pressure is applied between objects to be measured, and measuring the gap between objects to be measured. The system was configured so that the shade of color produced by applying pressure to the object to be measured was converted into the amount of gap between the objects to be measured using a previously prepared relationship chart between the color density and the amount of gap.

[Function] According to the above configuration, the amount of gap is determined by reading the shade of color of the pressure-sensitive paper sandwiched between the parts, so the amount of gap between the parts can be measured with constant flk and with high precision. can do.

[Example] Hereinafter, an example of the gap measuring method using pressure-sensitive paper according to the present invention will be described in detail with reference to the drawings.

Pressure-sensitive paper originally detects pressure distribution by the shade of color, and the pressure-sensitive paper used in the present invention is composed of two sheets of paper each consisting of three layers, as shown in Figure 1. is composed of a support 1a, an intermediate layer lb, and microcapsules 1c containing a coloring agent, and the other paper 2 is coated with a color developer 2a instead of the microcapsules 1c, and the microcapsules 1c of the paper 1 are When destroyed by pressure, the color developer 2a of the other paper 2 adsorbs the color former, causing a chemical reaction to develop color. The relationship between pressure and color density is the second
As shown in the figure, the higher the pressure, the greater the degree of destruction of the microcapsules containing the coloring agent, and therefore the color density increases. Further, the relationship between the size of the gap and the pressure applied to the pressure-sensitive paper is conceptually shown in FIG. 3. Based on this, the relationship between the size of the gap and the color density was investigated, and the result was as shown in FIG. 4, confirming that it was possible to convert the color density of the pressure-sensitive paper to the amount of gap.

Therefore, as shown in Figure 5, the diameter is 100 mm and the thickness is 15 mm.
Two test pieces are manufactured with both sides lapped to a flatness of 0.5 μm or less, and one of the test pieces 3 is provided with a recess 3a of maximum 65 μm in the center of one side, creating a gap of 65 μm when assembled. I did it like that.

Pressure sensitive paper 1, 2 between the above two test pieces 3, 40
Urethane rubber 5 was placed above and below the test pieces 3 and 4 as shown in Figure 6, and a load of 1000 kg was applied using an Amsura tester to cause color development on the pressure-sensitive paper. . As shown in Fig. 7, this pressure-sensitive paper is
The color density distribution was measured using a measurement system (prescale measurement system manufactured by Fuji Photo Film Co., Ltd.) consisting of a scanner) 6, an output device 7, an arithmetic device 8, and a monitor 9.

This coloring density distribution data was created based on the coloring density-gap amount conversion graph shown in FIG. 4, and was converted into gap amount data using conversion software to obtain the gap amount data shown in FIG. 8.

Although this example describes the measurement of the amount of gap between parts, the measurement is not limited to this. For example, when measuring the flatness of a specific part, it is necessary to The flatness of the object to be measured can be quantitatively determined by sandwiching a pressure-sensitive paper between the two and applying constant pressure between the two.

[Effects of the Invention] As explained above, according to the present invention, the gap between parts is calculated mechanically from the color density using the characteristics of pressure-sensitive paper, so that the actual gap when the parts are combined is The gap amount can be measured quantitatively with high precision, and the gap measurement time can be shortened compared to the conventional method.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing the coloring principle of pressure-sensitive paper, Figure 2 is a graph showing the relationship between pressure and coloring density, and Figure 3 is a graph conceptually showing the relationship between gap amount and pressure applied to pressure-sensitive paper. , 4th
The figure is a graph showing the relationship between the gap amount and color density, Figure 5 is a perspective view of the test piece used in the example, Figure 6 is a cross-sectional view when pressurizing the test piece, and Figure 7 is color density distribution. A perspective view of the measurement system, and FIG. 8 is a gap distribution diagram in the test piece. l. 2...Pressure sensitive paper 3゜4...Test piece

Claims (1)

[Claims] Pressure-sensitive paper that develops color when pressure is applied is placed between objects to be measured, and the shade of color produced by applying pressure to the object is measured using a pre-created correlation table between color density and gap amount. A gap measurement method using pressure-sensitive paper, characterized in that the gap is converted into the amount of gap between objects to be measured.