JPS5916201B2 - How to measure the transferred shape - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transfer shape measuring method for measuring transfer accuracy of a molded article using a contour map.

For example, when measuring how accurately a molded product manufactured by press molding has transferred the basic shape of a curved surface engraved on a mold, conventionally a stylus-type shape measuring device is used to measure the shape. was commonly practiced.

To measure transfer accuracy using this stylus-type shape measuring device, a stylus is brought into contact with the surface of the molded product and scanned, the shape of the molded product is determined from the amount of movement of this stylus, and this is engraved on the mold. The transfer accuracy of the molded product is measured by comparing it with the basic shape obtained. However, when measuring transfer accuracy using such a stylus-type shape measuring device, it is not easy to scan the entire surface of the molded product with the stylus.

Furthermore, when the needle is brought into contact with the molded article and scanned, there is a possibility that the surface of the molded article may be scratched. This invention was made based on the above circumstances, and its purpose is to optically create a contour map of a basic shape engraved on a mold or the like and a molded product molded from this basic shape, It is an object of the present invention to provide a method for measuring a transferred shape that can be easily and non-contactly measured by measuring the transfer accuracy with respect to the basic shape of the molded article from these contour maps.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In the figure, reference numeral 1 denotes a mold used for press working, for example, and a basic shape 2 consisting of a concave curved surface is engraved on this mold 1. In addition, 3 in the figure is a molded product having a convex curved surface molded from the mold 1, and this molded product 3 is placed on the mounting plate 1, and above the molded product 3, a minute A lattice 5 is provided with a large number of openings 5a in width. Further, a light source 6 is provided diagonally above the molded product 3, and a condensing lens T is provided facing the light source 6. Further, an imaging lens 8 and a photographic plate 9 are disposed vertically above the molded product 3, and a photographic plate 9 is disposed opposite to the imaging lens 8. It is configured to be created. Thus, when the light L1 is emitted from the light source 6, the light L1 is focused by the condenser lens T and illuminates the molded product 3 through the grating 5.

After that, the light L1 is reflected by the molded product 3, and the reflected light L1
2 passes through the grating 5 and forms a contour map 10 of the molded product 3 as shown in FIG. 4 on the photographic plate 9 via the imaging lens 8. If a contour map of the basic shape 2 engraved on the mold 1 is obtained in the same manner, a contour map 11 is obtained which is symmetrical to the contour map 10 of the molded product, as shown in FIG. In the contour maps 10 and 11 created in this way, if the molded product 3 had accurately transferred the basic shape 2 of the mold 1, the contour maps 10 and 11 would have mirror symmetry. Therefore, if these are turned over and polymerized, the contour lines will match without shifting.

However, if the transfer accuracy of the molded product is poor, the contour lines of the contour maps 10 and 11 may deviate, and as shown in FIG. Therefore, the error can be determined from the transfer accuracy of the molded product 3 and the order of the amount of deviation. In the above embodiment, the moiré topography method was used to create the contour map, but even if the contour map was created by other means such as the holography method or the interferometer method, the above The transfer accuracy of the molded product can be measured in the same manner as in the examples.

In addition, we have described molded products that are molded from a basic shape engraved on a mold, such as in press processing, as targets for measuring transfer accuracy.However, for molded products that do not have a basic shape, such as in cutting processing, theoretical By finding the basic shape and creating a contour map, the transfer accuracy can be measured in the same manner as in the above embodiment. Furthermore, in the above embodiment, a photographic plate was used to create a contour map of the molded product, but instead of this photographic plate, a diffuser plate was used, and a contour map of the basic shape was arranged by superimposing the diffuser plate. By projecting the contour map of the molded product onto the diffuser plate and measuring the deviation between the contour map of the basic shape and the molded product using the naked eye or a television camera, the transfer accuracy of the molded product can be measured in a short time. It can also be used in production lines, etc. Furthermore, it goes without saying that even if the basic shape is a convex curved surface and the molded product is a concave curved surface, the transferred shape can be measured in the same manner as in the above embodiment. As described above, in this invention, a contour map is created between the basic shape and the molded product, one of which is a concave curved surface and the other is a convex curved surface, and the moiré fringes generated by overlapping these contour lines are used to form the molded product. It is characterized by measuring the transfer accuracy for the basic shape of the product.

Therefore, it has become possible to easily and non-contactly measure the transfer accuracy of molded products, which not only improves efficiency, but also allows measurement without damaging the surface of the molded product. It has great practical value.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal sectional view showing a mold in which a basic shape is engraved, FIG. 2 is a schematic configuration diagram showing a means for creating a contour map, and FIG. 3 is a contour map of the basic shape, FIG. 4 is a contour map of the molded product, and FIG. 5 is a plan view showing moiré fringes caused by the superimposed contour maps. 2...basic shape, 3...molded product, 10,
11...Contour map, 12...Moire fringes.

Claims (1)

[Claims] 1 The light emitted from the light source is made into parallel light by an optical system, and this parallel light is separately irradiated through a grating to the basic shape that corresponds to the two objects with the irregularities of the molded product obtained from this basic shape, and each irradiated light is A mirror-symmetric contour map is created using the reflected light of each object, and one of the above two high-level contour maps is turned over and the two are superimposed to obtain moire fringes due to moire development. A method for measuring a transferred shape, characterized by measuring the amount of deviation.