JPH03107703A - Dimension measuring method - Google Patents

Abstract

PURPOSE:To take an accurate measurement by combining fine partial lighting with image processing discrimination by irradiating a formed part in a measured section direction with laser slit parallel light of several mum in width passes through a slit. CONSTITUTION:The formed part 2 is irradiated in the measured section direction with the laser slit parallel light 3 of several mum in width passed through the slit 7 slantingly at an angle theta by a laser light projection device 4. The formed part 2 in an unfinished state is arranged on a table 8 which is movable in, for example, an X-Y axis direction. Then the dimension measuring place of the formed part 2 is irradiated slantingly with the laser light parallel light 3 of several mum in width to make a stripe of light 5 on the formed part 2. The stripe of the light 5 is bent at a rugged part, i.e. a part curved to a burr part 1, the boundary point X is enlarged as to an inner and an outer peripheral part and picked up as an image by a CCD camera 6, and the interval to the other bending point X' is measured to find an accurate inner peripheral point.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for measuring the dimensions of an unfinished molded product.
Specifically, the present invention relates to a dimension measurement method that automatically measures dimensions by using laser slit light and image processing in combination.

[Prior Art] Conventionally, when measuring the dimensions of a molded product with burrs in an unfinished state after molding, the burrs distract from the overall shape and make it difficult to confirm the end face, resulting in extremely inaccurate measurement results. I couldn't get it.

To solve this problem, it is necessary to provide strong lighting to clearly capture the outline, or to measure the dimensions after removing burrs from each molded product and finishing it.

[Problems to be Solved by the Invention] However, the illumination method described above is troublesome to adjust because the illuminance changes depending on the shape and color of the molded product being measured, and the measurement method that removes burrs requires a COD camera. When performing measurements using image processing, it is difficult to distinguish between the remaining burr and the end face of the molded product because it is measured using a flat image, which is a major drawback that makes automatic measurement difficult.

It is an object of the present invention to eliminate such drawbacks and to provide a dimension measuring method that combines minimal partial illumination and image processing discrimination to achieve accurate measurements.

[Means for Solving the Problems] The present invention will be described in detail with reference to the drawings.As shown in FIG. The laser slit parallel light 3 of several micrometers that has passed through the slit 7 is irradiated obliquely by θ° in the measurement cross-sectional direction of the molded product 2, as shown in FIG. The bending point X where the light streak 5 shown on the measurement surface moves from the end of the molded product 2 to the burr portion 1 is recognized by image processing of the CCD camera 6, and one bending point
It is characterized by measuring the dimension from to the bending point X' on one side.

[Effect] The operation of the present invention will be explained based on the drawings.

First, the unfinished molded product 2 that has been formed is placed on a table 8 that is movable, for example, along the X-Y axes, as shown in FIG. Next, a laser slit parallel beam 3 with a width of several micrometers is irradiated diagonally to the dimension measurement point of the molded product 2, and a light streak 5 is raised on the molded product 2 as shown in FIG. 5 is bent at the uneven part, that is, the part where it moves to the burr part 1, and this bending point to find accurate inner and outer peripheral points.

[Example] In carrying out the present invention, it is more useful if the molded product 2 to be measured has a complex structure rather than a flat simple structure as shown in the figure, and in this case, the measurement surface is an end surface. The measurement range is wide.

[Effects of the Invention] With the above configuration of the present invention, dimensions that were conventionally measured by human judgment can now be automatically measured using a measuring device. Therefore, human measurement errors and individual differences can be eliminated and stable and accurate measurements can be made.

In addition, it has become possible to perform measurements with good reproducibility, resulting in high repeatability.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an embodiment of the measuring method of the present invention. FIG. 2 is a plan view of the molded product. 1... Burr 2... Molded product 3... Laser slit parallel light 4... Laser projector 5... Light streak 6... CCD camera 7... Slit 8...
・Table χ, X′...Bending point

Claims (1)

[Claims] A laser beam projecting device 4 is used to irradiate parallel laser slit light 3 several micrometers wide that has passed through the slit 7 at an angle of θ° in the measurement cross-sectional direction of the molded product 2 having any remaining burrs 1. The bending point X where the light streak 5 on the molded product 2 moves from the end of the molded product 2 to the burr 1 is recognized by image processing by the CCD camera 6, and the bending point X from one side of this bending point X to the other bending point Dimension measurement method characterized by measuring dimensions