JPS6093306A - Article positioning method - Google Patents

Abstract

PURPOSE:To make precise measurement possible in case of measurement of the shape of an article such as out of roundness or the like, by jetting compressed air uniformly from a jetting member consisting of a porous material and fitting an object to be measured to this jetting member with a narrow gap between them to hold the objet to be measured in the stable state. CONSTITUTION:Compressed air is supplied to an air chamber 11 provided in a supporting plate 7, which is supported freely rotatably on a base plate 10 through a thrust bearing 9, through an air path 12. Compressed air is jetted uniformly from the outside face of a part projected from the supporting plate 7. The outside diameter of a jetting member 8 is so determined that the inside diameter of a cylindrical object 1 to be measured whose center should be obtained is slightly larger than the outside diameter of the jetting member 8 and the object 1 to be measured can be fitted easily to the jetting member 8. Even if the gap between the inside circumferential face of the object 1 to be measured and the outside circumferential face of the jetting member 8 is not uniform, this ununiformity is corrected immediately, and the width of the gap is made uniform throughout the circumference. Thus, the center of the object 1 to be measured coincides with the center of the jetting member 8.

Description

[Detailed Description of the Invention] (Technical Field) The article positioning method of the present invention is suitable for measuring the shape of an article such as roundness, performing high-precision processing on the article, or for high-precision article assembly. It can be used when doing.

(Background Art) In order to measure the shape, process, and assemble an article, for example, the center position of the article may be determined. Conventionally, the center position of the article has been determined as follows.

First, when an article is cylindrical and the center position is determined based on the inner circumferential surface of the article, the methods shown in FIGS. 1 to 3 are often used. The example shown in Figure 1 is a cylindrical object to be measured (
Refers to an item that should be centered. same as below. )■ fitted onto the cylindrical positioning pin 2, the example shown in Fig. 2 is as follows:
An object to be measured 1 is fitted around a truncated conical pin 2.

On each side, the center of the pin 2 is taken as the center of the object to be measured l fitted over it. However, when centering the object to be measured in this way, in the example shown in FIG. This will cause a difference in measurement results due to the gap that is not possible. Further, in the example shown in FIG. 2, the support of the object to be measured becomes unstable, which inevitably causes errors in the measurement results. Furthermore, as shown in the example shown in Fig. 3, the inner circumferential surface of the cylindrical object to be measured l is held down by the jaws 3 of a chuck driven by pneumatic or hydraulic pressure, and the center of the chuck is aligned with the object to be measured. In the centering method, even when using the most accurate chuck currently in use under the best conditions, the measurement accuracy is about 1 to 3 gm, and there are errors in the shape of the object to be measured, the jaws 3,
In reality, the variation in the force applied to 3 causes a larger difference in the measurement results.Also, since the claw 3 is pressed against the object to be measured over a narrow area, the surface of the object to be measured may be scratched. easy.

Further, when determining the center position of an article in the +1 shape with reference to the outer circumferential surface, methods such as those shown in FIGS. 4 and 5 are often used. The example shown in FIG. 4 is a well-known method for determining the center position of a cylindrical object to be measured l using block 4. It is unavoidable that errors in the measurement results of the center position occur due to errors in the size and shape of the object to be measured. Furthermore, as shown in FIG.
The method of determining the center position by holding down the center position with reference to the inner circumferential surface shown in FIG.

Furthermore, as shown in FIG. 6, one end surface of the object to be measured (square or rectangular) is placed on the prong 6 which is IM-fixed on the top surface of the measurement board 5, and the object to be measured is measured using this end surface as a reference. In the method of determining the center position of the object 1, it is necessary to accurately know the dimensions of the object 10 to be measured, which not only makes the regular work troublesome, but also makes it difficult to perform precise measurements.

(Object of the Invention) An object of the present invention is to provide a method for positioning an article, which eliminates the above-mentioned inconveniences, allows easy and accurate positioning of an article, and does not damage the article during measurement. It is said that

(Structure of the Invention) In the method for positioning an article of the present invention, compressed air is uniformly ejected from a blowing member made of a porous material that is set up on a support plate and positioned in advance, and then the article, which is an object to be measured, is are fitted with a small gap in between, and the object to be measured is moved on the support plate by the compressed air blowing out from the fume member toward the surface of the object to be measured, and the fume member and the object to be measured are The compressed air jetting out from the gap between , the position of the article is determined from the predetermined position of the blowing member as described above.

(Embodiments of the Invention) Next, the present invention will be explained in more detail with reference to drawings showing embodiments.

FIG. 7 shows an embodiment in which the center position of a cylindrical article is determined by the positioning method of the present invention.

A cylindrical blowhole member 8 made of a porous material obtained by sintering granular metal or the like is planted on the upper surface of the central portion of the support plate 7 . The central axis a of this fumarole member 8 is set in advance to be as precise as rrf by an appropriate method.
Since the process of calibrating only needs to be done once, it is possible to use a tedious method and obtain fairly accurate measurements.

Compressed air is supplied through an air passage 12 to an air reservoir 11 provided inside a support plate 7 rotatably supported by a plywood 10 via a thrust bearing 9 . Furthermore, this air reservoir 1
The compressed air supplied to the blower 1 enters the fine through holes inside the blower member 8 from the bottom surface of the blower member 8 exposed to the air reservoir 11, and is uniformly jetted out from the outer surface of the part protruding from the support plate 7. do. The inner diameter of the cylindrical object l to be centered is slightly larger than the outer diameter of the cylindrical fume member 8. The outer diameter of the blowing member 8 is determined.

When determining the center of the object 1 to be measured based on the inner circumference, the object 1 to be measured is fitted onto the fume member 8, and the ventilation path 12 and the air reservoir 11 are
The compressed air is sent into the fine holes in the fume member 8 through the fume gas member 8 and is ejected from the outer circumferential surface of the fume member 8 toward the inner circumferential surface of the object to be measured l.

This jetting of compressed air is uniformly performed over the entire circumference of the fume member 8, so when the object to be measured l is fitted onto the fume member 8, the inner peripheral surface of the object to be measured l and the outer circumference of the fume member 8 Even if a deviation occurs in the gap between the two surfaces, this deviation is immediately corrected, the width of the gap becomes the same over the entire circumference, and the center of the object to be measured I coincides with the center of the blowing member 8. In other words, when the above-mentioned gap is uneven, the force of the compressed air pushing against the inner circumferential surface of the object to be measured 1 will be strong (high pressure) where the gap is narrow, and weaker (low pressure) where the gap is wide. To become
If there is any deviation, the force of the compressed air will move the object to be measured in a direction that equalizes the gap, and the object to be measured will be removed in an extremely short time.
The center of coincides with the center of the blowing member 8.

In the illustrated embodiment, since the support plate 7 rotates around the center a of the blowing member 8, the support plate 7 is rotated while the center of the object to be measured is aligned with the center a by the jet of compressed air.
rotate the stylus 13 of the comparator so that the circumferential surface of the object to be measured is
If the object is tracked using the same method, the roundness, etc. of the object to be measured l can be accurately measured.

Next, FIG. 8 shows a state in which the center position 6 of a cylindrical article is measured by the method of the present invention. When measuring the center position of such an article based on the outer circumference, 7! +l
The device used for this purpose is to fix a cylindrical holder 14 to the upper surface of the support plate 7, and to cover an air pocket 11 formed over the entire length on the inner circumferential surface of the holder 14, and to attach a cylindrical blower member to the upper surface of the support plate 7. I am wearing 8. The center position of this blowing member 8 is also set in advance as in the case of the first embodiment. The compressed air sent to the outer circumferential side of the blower member 8 through the ventilation path 12 and the air reservoir 11 is uniformly ejected from the inner circumferential surface of the blower member 8. Since the inner diameter of the fume member 8 is slightly larger than the outer diameter of the object to be measured 1 when the center is located, the object to be measured 1 is fitted into the fume member 8 and the air passage 12 and the air reservoir 11 are inserted. By blowing out the compressed air supplied through the blower member 8 to the inside of the blower member 8, the width of the gap between the inner peripheral surface of the blower member 8 and the outer surface of the object to be measured l becomes uniform over the entire circumference, and the The center of the measurement object 1 coincides with the center of the blowing member 8. Note that the porosity of the porous material constituting the fumarole member 8 is the same as that of the porous material constituting the porous static pressure gas bearing.

In the above-described embodiments, a method was shown in which the center of the blowing member 8 and the center of the object to be measured l were aligned and the center position of the object to be measured l was determined. When determining the position of the article by this method, the centers of both do not necessarily have to coincide. For example, when a scalene polygonal object is fitted to a fume member with a similar cross-sectional shape, there will be a difference in the force pressing the object to be measured on each side, so the center positions of both will not necessarily coincide, but they will The positional relationship of is always constant. Therefore, even if the centers do not coincide, the article can always be positioned at a fixed location.

(Effects of φ) The article positioning method of the present invention is configured as described above, and thus exhibits the following effects.

(1) It is possible to easily and quickly determine the position of an article as a target object by simply fitting it into the blower member.

(2) Due to the average effect of compressed air, the center position can be determined accurately in the field with better accuracy than the shape error of the article.

(3) Accuracy is improved compared to conventional methods, and accuracy of 11Lm or less can be obtained.

(4) Accurate centering work can be performed repeatedly, allowing measurements with good internal regularity.

(5) Since a uniform force is applied to the object to be measured over its entire circumference, the object is not deformed at regular intervals, and even objects made of flexible materials can be accurately positioned.

(8) Measurement results are not affected by ambient temperature, etc., and no heat is generated during measurement, so articles etc. are not deformed by heat.

(7) Since there is no contact with the article during positioning and no strong pressure is applied, there is no possibility of damaging the article.

(8) The device used for positioning has no rJf moving parts or contact parts with the object to be measured, so there is no friction.
The service life is semi-permanent, and there is no decrease in accuracy.

(8) Since no lubricant such as oil is used, the object to be measured, the operator's hands, clothes, etc. are not soiled.

(lO) With the same device, the center position of not only circular but also regular polygonal articles can be determined, and the position of scalene polygons can also be determined.

(11) Since the blower member is made of a porous material, the force to hold the object to be measured in a predetermined position can be strengthened, which is useful when bringing the probe into elastic contact with the outer circumferential surface of the object to be measured. .

That is, according to an experiment conducted by the present inventor, as shown in FIG. A nozzle 16 is provided that blows out compressed air in the direction of When trying to support the flat i17, the relationship between the hair length W and the distance ah is as shown in Figure 1O. According to this, the smaller the distance between the top surface of the pedestal and the bottom surface of the first root, the greater the weight it can support, but once the distance is less than 10 degrees, the weight that can be supported even if the distance is further reduced is The maximum weight that can be supported without increasing is about 5 kg.

On the other hand, the upper surface of a blower plate made of a porous material and having the same shape and size as the upper surface of the pedestal 15 was placed opposite to the lower surface of the flat plate 17, and 5.17 m1 of compressed air of 5 kg/cm' was applied.
When the air is ejected uniformly from the top surface of this fume plate at a rate of n,
Distance between the two sides of the “fumarole plate” and the bottom surface of the flat plate and the weight W of the flat plate 17
The relationship between the two is shown in Figure 11. According to this, when the distance #-h exceeds 10 m, the weight that can be supported is almost the same as that of the nozzle shown in Figure 9, but when h becomes 10 pm or less, the weight that can be supported is even greater. The weight increases, reaching a maximum of around 18 kg.

(12) As a result, the pressure of the compressed air used during measurement does not need to be relatively low, so a simple compressed air source is sufficient, and there is no danger of bursting or the like.

(13) Since the fume member 8 made of porous material has countless micropores opening over its entire circumference, the object to be measured receives force uniformly over its entire circumference, and Precise measurements can be performed with less bias.

(Application Example) According to the method of the present invention, the position of the article can be determined easily, quickly, and precisely as described above. When processing an object to be measured based on its position, an external force is applied to the object. If the external force is small, the force of the compressed air ejected from the blowing member 8 can sufficiently support the object to be measured, but if a relatively large external force is applied, there is a risk that the center position will shift.

In order to prevent such deviation, 71 is shown in Figures 12 and 13.
As shown in FIG. 2, four parts 18 may be formed on the -L surface of the support plate 7 or holder 14 on which the object to be measured 1 is placed, and these four parts 18 may be freely connected to a negative pressure source. When processing the object to be measured after locating its center, first cut off the communication between the four parts 18 and the negative pressure source, and blow out compressed air from the blower member 8 to locate the center of the object to be measured. After aligning the position with the center position of the blowing member 8, the gate 81118 is communicated with a negative pressure source, and the object to be measured 1 is adsorbed onto the upper surface of the support plate 7 or the holder 14. As a result, the object to be measured l whose center position is set does not move easily, and even when an external force is applied due to machining or the like, the set center position does not shift. A porous material may be fitted into the recess 18 on each side, and the object 1 to be measured may be adsorbed onto the surface of the porous material.

[Brief explanation of drawings]

Figures 1 to 6 show six conventional examples of article positioning methods; Figure 1 is the first example, Figures 2 and 2 are vertical sectional views of the second example, Figure 3 is the third example, Fig. 4 is an end view of the fourth example, Fig. 5 is an end view of the fifth example, Fig. 6 is a side view of the sixth example, and Fig. 5 is an end view of the fifth example.
The following figures are diagrams for explaining the present invention. Figure 7 is a vertical cross-section of the device used when centering the article based on the inner circumference, and Figure 8 is a longitudinal cross-section of the device used when centering the article based on the outer circumference. Front view, No. 9
The figure is a vertical cross-sectional view showing a structure for ejecting from a nozzle for comparison, FIG. 10 is a diagram showing the relationship between the weight supported by the structure of FIG. 9 and the gap formed by compressed air, and FIG.
The figure is a similar diagram when using porous material, 12th to 13th
The figures are longitudinal sectional views showing two examples of application of the present invention. 1: Object to be measured, 2: Pin, 3: Claw, 4: V block, 5
: Surface plate, 6: Block, 7: Support plate, 8: Fumarole member, 9
Nilast bearing, lO2 plywood, 1 air reservoir, 12 2 air passages, 13: stylus, 14: holder, 15: pedestal, 16: nozzle, 17: flat plate, 18: recess. Patent applicant: Kosaka Institute Co., Ltd. Director: Kinzo Koyama (and one other person) Figure 4 Figure 5 Figure 6 Figure 9 Figure to Figure 1I Figure 13

Claims (1)

[Claims] After uniformly blowing out compressed air from a porous blower member positioned in advance, the object to be measured is fitted with a small gap in between, and the blower member is placed on the surface of the object. A method for positioning an object, in which the object to be measured is moved by compressed air that is blown toward the blower, the positional relationship between the object and the blower member is always constant, and the object is positioned from the position of the blower member.