JPS59166807A - Method and device for confirming shape - Google Patents

Abstract

PURPOSE:To measure the dimensions of an object to be measured without moving it by converting a shape of the object to be measured to a silhouette in a prescribed field of view, measuring a shape of this silhouette by a line image sensor, and calculating it. CONSTITUTION:When an object 1 to be measured is placed on a measuring base 22a, and a line image sensor 6 is moved toward the other end from one end of a screw lever 11 in a range of a field of view 4, the line image sensor 6 scans the first reference silhouette 21 in the first direction at first, and sends this measuring output to an operating means 24. Subsequently, by detecting a pulse output from a moving extent detector, a width data and a data in the lengthwise direction of the object 1 to be measured are inputted. Next, an average of the width data is calculated by the operating means 24, also whether this average value is within a range of a designated variation stored in advance by the operating means or not is compared, an average of its width data is calculated by the operating means 24, and dimensions of the object 1 to be measured are calculated from the width data of the object 1 to be measured, and a pitch number output of a moving extent generator, namely, through-holes 14, 14.

Description

Detailed Description of the Invention This invention converts the shape of an object to be measured into a silhouette within a predetermined field of view, measures the shape of this silhouette with a line image sensor, and calculates this to calculate the shape of the object to be measured. This is to be confirmed.

When measuring the shape of an object by optically or electrically measuring the silhouette of the object that is illuminated from the back, the method involves weighing or moving the object and fixing the sensor. There is a method of fixing the object to be measured within the field of view and moving the sensor to measure it. In the former case, when the shape of a single object to be measured fills the field of view, for example, in the case of the oil tank shown in Fig. As shown in Figure 2), errors occur due to viewing angle.

That is, in Fig. 1, measure the distance from the viewpoint A to the center of the cylindrical object to be measured 1, look at the object to be measured 1 from the viewpoint A, measure the elevation angle θ, and calculate the height H from tanθ=H/L.
When , the height H' is calculated, and an error Δ occurs. In order to prevent the occurrence of this error Δ, the diameter Φ of the object to be measured 1 is known in advance, Δ corresponding to this diameter Φ is found, and A is found by subtracting the error Δ from A'. bite For this reason, the former method has the drawback of always requiring correction.

In the latter case, it is necessary to know when the measurement of the object to be measured 1 begins and ends, and it is extremely difficult to know the times.

This invention attempts to solve these drawbacks.
By forming a silhouette of the object to be measured within a predetermined field of view and providing reference silhouettes of known dimensions at the upper and lower ends of this silhouette, it is possible to easily know the measurement start point and measurement end point. This is the purpose.

An embodiment of the present invention will be explained below with reference to the figures. In other words, in FIGS. 3 and 4, a light source 2 is provided on one side of the object to be measured 1 at a predetermined distance, and between this light source and the object to be measured 1. is provided with a lens 3 that converts the light beam from the light source 2 into parallel light beams. Further, a predetermined field of view 4 is formed on the other side of the object to be measured 1 orthogonal to the parallel rays, and within this field of view, the silhouette of the object to be measured 1 formed by the light rays projected from the light source 2 can be seen in the first direction. A line image sensor 6 that scans along the direction is installed. This line image sensor is provided in a housing 7, and one side of the housing is provided with a lens 8 that focuses parallel light rays on the field of view 4, that is, on the line image sensor 6, and an aperture 9 that adjusts the depth of focus. A threaded rod 11 having a spiral thread groove is screwed into the housing 7, and by rotating this threaded rod, the line image sensor moves in a second direction intersecting the scanning direction. A disk 13 having a gear 12 on the periphery is fixed to the other end of the screw rod 1, and a plurality of through holes 14, 14 are formed in this disk so that the screw rod 11 can be connected to the screw rod 11.
A predetermined interval, for example, 0.1
They are arranged at a pitch of mm. and through hole 14
On the axis of the disc, a light projecting element 16 is provided on one side of the circular plate 143, and a light receiving element 17 for receiving light from the light projecting element 16 is provided on the other side of the circular plate 3. A gear 18 meshes with the disk 13, and this gear is connected to a rotating shaft of a motor 19. In other words, the line image sensor 6 is
means of transportation are constructed.

The through holes 14, 14 provided in the disk 13F, the light projecting element 16, and the light receiving element 17 form a movement amount generator that measures the movement amount of the line image sensor. This movement amount generator is configured to generate one pulse for every 0.1 mm of movement of the disk 13, for example.

Further, as shown in FIG. 5, within the field of view 1y4 and in the second moving direction of the line image sensor 6, a first reference silhouette 21 having a known width dimension is located at one end of the silhouette of the object 1 to be measured. In addition, a second reference silhouette 22 having a known width dimension is formed at the other end of the silhouette of the object 1 to be measured. The second reference silhouette 22 includes a total of 711 units 22a on which the object to be measured 1 is placed.
It can be formed by

The output of the line image sensor 4 is inputted via the control section 23 to a calculation means 24 such as a microprocessor, and the output of the light receiving element 17 is also inputted to the calculation means 24.

In the above configuration, the object to be measured 11 is measured as follows.

The object to be measured 1 is placed on the measuring table 22a, and the field of view 4 is
When the line image sensor 6 is moved from one end of the screw rod 11 to the other end within the range of At the same time, the calculation means 24 stores the fact that the dimension measurement of the object to be measured 1 has started. Radiation data and lengthwise data of the object to be measured 1 are acquired by sensing the pulse output from the movement and quantity detector. At the same time, the calculation means 24 calculates the average of the width data, and compares the average value to see if it is within a specified variation range that is stored in advance by the calculation means. When the error occurs, the measurement is performed again, or a signal indicating that the object 1 to be measured is not within the specified variation range is output. When the dimension of the object to be measured 10 is within the specified variation range, the width dimension of the second reference silhouette 22 is read by the line image sensor 6, and the width dimension, that is, the measurement table 2 is read.
The calculation means 24 compares whether the width dimension of 2a matches the dimension stored in advance by the calculation means 24, and if they match, ends the measurement of the object to be measured 1, and calculates the average of the width data by the calculation means 24. The dimensions of the object to be measured 1 are calculated from the width data of the object to be measured and the movement amount generator, that is, the pitch number output of the through holes 14, 14.

According to this invention, the dimensions of the object to be measured can be measured without moving the object, so if the object to be measured is moving on a conveyor or the like, it can be stopped for a short period of time, for example, 5 seconds. Therefore, the structure supporting the object to be measured requires almost no modification. Furthermore, even if the dimension of the object to be measured in the direction of erosion is large, no visual angle correction is necessary as long as it is within the dimension of the moving means.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a conventional measuring method, FIG. 2 is a diagram showing the shape of an object to be measured by the measuring method of FIG. , FIG. 4 is an external perspective view, FIG. 5 is a diagram showing a silhouette within the visual field, and FIG. 6 is a flowchart of the shape confirmation method of the present invention. 1... Object to be measured, 2... Light source, 3... Lens,
4... Field of view, 6... Line image sensor, 7...
/-Using, 8... Lens, 9... Aperture, 11.
... Screw rod, 12... Gear, 13... Disc, 14.
...Through hole, 16... Light emitting element, 17... Light receiving element,
18... Gear, 19... Motor, 21... First reference silhouette, 22... Second reference silhouette, 2
2a...Measuring table, 23...Control unit, 24...Calculating means. Figure 2

Claims (2)

[Claims] (1) When the light beam is applied from one side of the object to be measured, the K
The silhouette of the object to be measured, which is formed within a predetermined field of view by this light beam, is scanned along a first direction by a -line image sensor, and the silhouette of the object to be measured is scanned by a -line image sensor in a second direction that intersects with this scanning direction. At the same time, the amount of movement of the line image sensor is measured, and the size of the object to be measured is calculated from this amount of movement and the scanning output. A signal to start measuring the silhouette of the object to be measured is emitted by detecting a first reference silhouette having a known dimension provided on one end side 1 of the silhouette of the object to be measured in the moving direction, and A shape confirmation method in which a signal for terminating the measurement of the silhouette of the object to be measured is emitted by detecting a second reference silhouette having a known dimension provided at the other end of the silhouette of the object to be measured. (2) A light source provided on one side of the object to be measured and a light beam projected from the light source within a predetermined field of view set on the other side of the object to be measured. 1. a line image sensor that scans a silhouette along a first direction; The line image sensor includes a moving means for moving the sensor in a second scanning direction intersecting the first scanning direction, and a moving amount generator for measuring the moving amount of the sensor moved by the moving means. and the output of the movement amount generator,
l A first reference shift having a known dimension is provided at one end of the shift floor of the object to be measured within the field of view and in the second scanning direction of the line image sensor. The measurement of the silhouette of the object to be measured is started by detecting the object to be measured. A shape confirmation device comprising: a calculation means for completing the measurement of the silhouette of an object to be measured;