JPS61256211A - Identification for shape of object - Google Patents

Abstract

PURPOSE:To achieve non-contact identification of shape of an object and always at the same accuracy, by irradiating the object being measured with two parallel beams in such a manner that the beams are partly intercepted separately by a measuring end thereof to detect the area intercepted thereby. CONSTITUTION:A photosensor 1 comprises a light receiving section 3 with a condenser lens 2 and a trnasducer section 5 with a transducer 4. Sensor elements 11 are driven sequentially at a fixed time interval by a timing pulse from a pulse generator 13 and the resulting output signals are converted to a series with a parallel-series conversion circuit 14 to be fed to a processing circuit 15. Then, an arithmetic processor 12 detects the positions of measuring ends 9a and 9b based on the output signal of the circuit 15 to calculate the dimensions between the ends 9a and 9b. The detection is done by checking the widths Wa and Wb of portions of parallel beams 10a and 10b or photosensors 1a and 1b as itnercepted by both the ends 9a and 9b of a cam shaft. Known values are used to compute the magnifying power and dimensions of an optical image, array interval of the elements 11 and the like.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of determining the shape of a bar, shaft, etc. without contact using light.

(Prior art) Conventionally, when determining the shape of bars, shafts, etc., such as cylindricity, bending, taber, etc., measuring instruments such as gauges suitable for various shapes are selected, and measuring instruments for each are measured. Various shapes are discriminated by, for example, making contact with the measuring end of the object whose shape is to be measured.

On the other hand, in contrast to this method of determining the shape of an object by bringing a gauge or the like into contact with it, methods of determining the shape of an object using light can be performed without contact and are easy to automate. It has been widely used recently. For example, place the object to be measured on a specific measuring table! The shape of the object can be determined by shining an illumination light on it from a predetermined direction, photographing it with an ITv (industrial TV camera) or COD camera, etc., and processing this image signal with a computer, etc. There is something I did.

(Problem to be solved by the invention) However, in the former case, in the conventional shape discrimination method, it is necessary to select a gauge etc. for each object to be measured having each shape, and this work is complicated. It is. Further, it is difficult to automate the work of bringing the measuring end into contact with the measuring end to check the degree of conformity, etc., and therefore the work efficiency is lowered and the production efficiency is lowered.

On the other hand, the latter is contactless and easy to automate;
In the conventional method, the structure and setting of measurement devices such as an ITV camera, a computer, and a lighting lamp are complicated, resulting in high cost, and there are also limits to the size of the object to be measured.

Therefore, the object of the present invention is to be able to determine the shape of an object without contact, to easily configure and set up a measuring device, etc., and to always maintain the same accuracy (resolution) regardless of the size of the object to be measured.
The object of the present invention is to provide a shape discrimination method that can perform shape discrimination.

(Means and operations for solving the above problems) In order to solve the above problems, the present invention provides two parallel rays (10),
(10), each part of which is the measurement end of the object to be measured (9) (
9a), (9b), and detect areas Wa, Wb (or unobstructed areas) of the parallel rays (10), (10) that are blocked by the object to be measured (9). Thus, at least two measurement ends (A, B, and C) of the object to be measured (8) are detected, and the preset shape of the object to be measured is determined based on the detection signals. Therefore, the shape of the object can be determined without contact, and the configuration and setting of the measuring device etc. is easy.
Regardless of the size of the object to be measured, shape discrimination can always be performed with the same accuracy (resolution).

(Example) Embodiments of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a schematic diagram illustrating an embodiment of the present invention in the case of measuring the outer diameter dimension of a shaft portion of a camshaft.

The optical sensors indicated by symbols (1) and (1) are condensing lenses (2)
.

(2) and a transducer (4) that converts the optical signal into an electric signal such as a charge.
) and a transducer section (5).

On the other hand, the lighting device indicated by the symbol (El) and (6) is a light source (7).
, (7) and projecting lenses (8), (8) for irradiating the light from the light sources (7), (7) as parallel rays, and these two optical sensors (1) , (1) and the illumination device (8), (e) are such that each optical sensor (1) and the illumination device (6) face each other in symmetrical positions with respect to the shaft portion (9), respectively. And each lighting device (8)
Parallel light rays (10) from to the optical sensor (1), (10
) are both radial ends (9a) of the shaft portion (9).
, (9a).

The transducers (4), (4) are semiconductor image sensors in which photodiodes or CODs (charge coupled devices) are arranged in a straight line at a predetermined interval so as to be orthogonal to the parallel beams (10), (10). It consists of Each element (11)... is sequentially driven at fixed time intervals by a timing pulse from a pulse generator (13) driven by an arithmetic processing unit (12), and the output signal is sent to a parallel-to-serial conversion circuit (14). , (14), and sent to the processing circuits (15), (15) through one signal line.

The arithmetic processing unit (12) includes each processing circuit (15), (15
) of each measurement end of the shaft (8) based on the output signal of
9a) and (9b), and detect the positions of the measuring end (9a),
(9b) to calculate the dimension between each measurement end (9a
), (sb) are detected by parallel light beams (10a) to optical sensors (la) and (lb).

Of (10b), the re-measurement end of the camshaft (9a)
.

This is done by detecting the widths Wa and Wb of the portions shielded by (9b). Here, the magnification and dimensions of the optical image or the arrangement interval of the sensor elements (11), and the optical sensors (1), (1) in the plane perpendicular to the parallel light rays are discussed.
A predetermined calculation is performed using a known value such as the distance W+ between the two as necessary.

FIG. 2 and FIG. 3 are overall views showing this embodiment.
The detection units (20) and (20) each having an optical sensor (1) and an illumination device (6) therein have the same arrangement configuration as each optical sensor (1) and illumination device (6) shown in FIG. It is arranged as much as possible.

Each detection part (20), (20) has a feed screw (21) respectively.
, (21), and this feed screw (2
1).

(21) is rotatably supported parallel to the shaft portion (9), and one end thereof is connected to the drive shaft of the motor (22).

In this way, the detection unit (20) and (20) are the motor (22).
Due to the rotation, the direction of arrows A and B, that is, the shaft part (9)
The measuring end (9a) is movable over a predetermined length along the axial direction of the measuring end (9a).

The position of (8b) is detected, and the detection signal is sent to the signal line (
18) to the arithmetic processing circuit (12).

Now, as shown in FIG. 4, between a predetermined length,
Three locations A at each of the measurement ends (9a) and (9b).

Detection is performed in B and C, and based on this, the preset straight cylindrical shape (I), drum shape (n), and curved shape (
An example of determining the shapes of (2), Taber shape (■), and drum shape (V) will be explained based on the flowchart of FIG.

First, in step (31), the motor (22) is driven to move the detection units (20) and (20), and in step (32), the detection units (20) and (20) are moved at three locations (A, B) respectively on the measurement ends (9a) and (9b). , C point) is detected. Here A and B.

The detected values on the measurement end (3a) side at point C are respectively Wla
, W2a, W3a, and the detected values on the @foot end (9b) side are respectively defined as W Ib, W2 b, and W3 b. In addition, in the loop (33), the timer indicated by step (30) is used to temporarily stop the measurement until the detection units (20), (20) reach a predetermined position.
,B.

When the detection of point C is completed, the motor (22) is stopped in step (35), and the dimensions (diameters) W^, W, at the three points are determined in the next step (36).

Calculate Wc. Step (37) is these dimensions W^
, WI, and Wc are all the same value. If they are all equal, it is determined in step (38) whether the detected values of either one of the measurement ends (la) and (9b) are all equal. If they are equal, the object to be measured (9) has a straight shape (1), and if they are not equal, it has a curved shape (III) in steps (39) and (39), respectively.
ao) is output.

On the other hand, if the dimensions are not all equal in step (37), the process proceeds to step (41), where it is determined whether all the dimensions are different. If all the dimensions are different, step (42) is performed. Object to be measured (9)
is outputted as having a tapered shape (IV). On the other hand, if everything is the same in step (41), it is determined in step (43) whether the size of the center part B is larger than that of both ends A and C, and if it is larger, the size of the center part B is determined as a drum shape (n). , if it is small, it is output as a drum shape (V) in steps (44) and (45), respectively, and the shape determination of the object to be measured is completed, or if necessary for the next measurement, 5TART (30 ).

In this way, according to the present invention, several types of shapes of the object to be measured whose shape is to be determined are set in advance, and it is determined whether the object to be measured is one of these shapes, so that shape determination can be performed extremely easily. I can do it.

Note that the present invention is not limited to the embodiments, and for example, (V
As shown in I), the measurement ends (9a) and (9b) are measured at multiple locations d1 to dn, the maximum and minimum values are determined, and based on this difference, it is determined that the object to be measured (3) is defective. The determination may be made as to whether or not it is a shape.

Further, in this embodiment, the detection unit (20) is connected to the object to be measured (9).
), (20) are moved, but the object to be measured (9) may be moved relative to the detection units (20), (20) in the opposite manner.

(Effects of the Invention) As is clear from the above description, according to the present invention, the shape of an object can be determined without contact, and the configuration and setting of the measuring device etc. is easy, regardless of the size of the object to be measured. It is possible to provide a shape discrimination method that can always perform shape discrimination with the same accuracy (resolution).

According to this embodiment, the detection units (20) and (20) are as follows:
Optical sensors (1), (1) and illumination device (El) are provided at symmetrical positions facing each other with respect to the object to be measured (9).
.

According to (6), when the diameter of the object to be measured is small, the distance #WI between the light beams 7 (1) and (+) is made small, and when the diameter of the object to be measured is large, the distance Wl is increased so that the object (9) is always Since only the positions of both ends (9a) and (9b) can be detected, the outer diameter dimensions of objects ranging from large to small can always be detected with the same optical sensor (1), (1). Therefore, the detection accuracy (resolution) and processing time can be kept constant regardless of the size of the object to be measured (9), resulting in simple, inexpensive detection with excellent accuracy and processing time, and high reliability. can be done.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a detection section in an embodiment of the present invention, and FIG.
The figure is an overall plan view showing the apparatus in the embodiment, FIG. 3 is a view taken in the second direction, FIG. 84 is a diagram showing the shape of the object to be measured, and FIG. 5 is a flowchart showing the embodiment. In the drawing, (1), (1)... optical sensor (8), (8)... lighting device (9)...... object to be measured ( 9a), (
9b)...Measurement end (10), (10)...Parallel rays (!2)
...... Arithmetic processing unit (20), (20)...
・Detection parts A, B, C...These are measurement force tanks. Figure 4 I LV n V

Claims (1)

[Claims] Two parallel rays are irradiated so that a portion of each is blocked by the measurement end of the object to be measured, and a region of each of the parallel rays that is blocked by the object to be measured (or a region that is not blocked) is detected. A method for determining the shape of an object, comprising: detecting at least two measurement ends of the object to be measured, and determining a preset shape of the object to be measured based on the detection signals. .