JPH06123608A - Wheel measuring device - Google Patents

Abstract

PURPOSE:To perform measurement within a short time while moving a vehicle by grasping the shape of the tread surface of a wheel and the shape of the inner side surface of the wheel as image signals and calculating the shape of the tread surface of the wheel and the diameter of the wheel from respective images. CONSTITUTION:The tread surface 4 of a wheel 1 is irradiated with a fine strip like light emitted from the light source 5 arranged on the ground and the inner side surface of the wheel 1 is irradiated with a fine strip like light emitted from a light source 6 arranged on the ground. The image of the part irradiated with light of the tread surface 4 is taken by the imaging device 7 arranged on the ground and the image of the part irradiated with light of the inner side surface of the wheel is taken by an imaging device 8. The image signals outputted from the devices 7, 8 are sent to an image signal processor 9. The processor 9 calculates the diameter of the wheel, the gradient of the tread surface of the wheel and the flange thickness and height of the wheel on the basis of the image signals.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wheel size measuring device for measuring the size of a wheel of a railway vehicle, for example.

[0002]

2. Description of the Related Art Conventionally, the shape, diameter and width of a wheel of a railway vehicle are measured by using a measuring jig made according to the shape. Therefore, in the measurement using these measuring jigs, only the wheels of the stopped vehicle can be measured, which requires a lot of manpower in the measurement, and there is a problem in that a difference easily occurs depending on a person who measures.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a wheel measuring device that solves the above problems.

[0004]

A wheel measuring device according to the present invention is a light source for irradiating a wheel tread surface and a wheel inner side surface with thin strip light, and an image pickup device for picking up an image of a portion irradiated with light on the wheel tread surface and the wheel inner side surface. The image signal processing device is characterized in that it is configured by an image signal processing device which inputs a video signal from each image pickup device and measures a shape of a wheel tread, a wheel diameter dimension, a wheel width dimension and an inner side surface shape.

[0005]

The wheel measuring device according to the present invention can grasp the shape of the wheel tread surface and the shape of the wheel inner side surface as video signals, and calculate the shape of the wheel tread surface, the wheel diameter dimension, and the inter-wheel dimension from the respective images. Therefore, it becomes possible to measure in a short time while moving.

[0006]

【Example】

Example 1. FIG. 1 shows the contours of the tread surface and the inner side surface 2 of the wheel 1. The shape of the wheel 1 is wheel diameter α, tread slope ψ,
It is represented by the flange thickness β and the flange height γ. In the figure, points A, B and C are measurement reference positions and are determined as follows. That is, point A
Is a point on the tread 3 which is separated from the inner side surface 2 by a predetermined distance 1 in the wheel thickness direction, for example, 65 mm. The point B is a point on the tread 4 which is separated from the point A in the radial direction of the wheel by a predetermined distance m, for example, 12 mm. The point C is the apex of the flange 3. Wheel diameter α
Is the diameter of the wheel passing through point A. The tread slope ψ is at point A
Is the slope of the tread in. The flange thickness β is the distance from the point B to the inner side surface 2 in the wheel thickness direction. The flange height γ is the distance from the point A to the point C in the wheel radial direction. On the inner side surface of the flange, at the point D, the wheel reference diameter N
Is engraved with a reference line that can be read, for example, a φ780 mm reference line.

FIG. 2 is a block diagram of a wheel measuring device according to the present invention,
FIG. 3 is an explanatory view showing a state where the wheel portion is irradiated with the strip-shaped light, and FIG. 4 is an explanatory view showing an example of the arrangement of the respective constituent devices. The strip-shaped light emitted from the light source 5 installed on the ground is applied to the tread surface 4 of the wheel 1, and the strip-shaped light emitted from the light source 6 installed on the ground is applied to the inner side surface 2 of the wheel 1. . The part where the wheel tread 4 is illuminated is imaged by the imaging device 7 installed on the ground, and the part of the wheel inner side surface 2 that is illuminated is imaged by the imaging device 8 from the inner side. The video signals output from the image pickup devices 7 and 8 are sent to the image signal processing device 9. The image signal processing device 9 determines the wheel diameter α, the tread slope ψ, the flange thickness β, and the flange height γ based on the input video signal.
To calculate. The two strips of light emitted from the light source 5 and the light source 6 need to coincide with the straight line connecting the center of the wheel and the tread as shown in FIG. Video is input by the imaging devices 7 and 8 in accordance with the timing when the wheels are detected. The photoelectric switch detects that the wheel 1 has arrived at the measurement point, and the image pickup devices 7 and 8 input images in accordance with the detected timing. Therefore, even if the wheel diameter changes, the first wheel tread 4 is illuminated. The light and the second light applied to the inner side surface do not deviate from the straight line connecting the tread surface and the central axis of the wheel.

Further, the first light and the second light are changed by the change of the wheel diameter.
The phenomenon that the line with the light of is shifted from the straight line connecting the center of the wheel and the tread surface causes a measurement error.
In the positional arrangement of the equipment shown in FIG. 5, the error amount is minute as shown in FIG. 5 and does not affect the measurement accuracy. For example, if the wheel diameter changes from 700 mm to 900 mm as shown in FIG. 5, it is assumed that a belt-shaped light is emitted at an elevation angle of 45 degrees toward the wheel tread, and an image of the wheel tread is captured directly below the wheel. If this is done, the deviation between the straight line connecting the center of the wheel and the tread and the line of narrow strip light is about 4 degrees, and the resulting dimensional error is about 0.3% with respect to the wheel flange height direction.
In addition, this measuring device uses a method of calculating the wheel diameter by adding the flange height dimension to the reference diameter dimension obtained from the reference groove on the inside of the wheel. The measurement error caused by the angle deviation due to the change is sufficiently small, and can be sufficiently ignored with respect to the required measurement accuracy. In addition, when the device is installed outdoors, a filter that transmits only the wavelength of the light source may be added to the image pickup device to remove an error due to the influence of sunlight.

FIG. 6 shows a block diagram of the wheel measuring device. Video signals output from the image pickup devices 7 and 8 are sent to A / D converters 13 and 14, respectively, and converted into digital signals. The image data converted to digital signals is CP
It is stored in the frame memory 16 by U15, and binarization processing and edge component extraction processing are performed to calculate the shape and dimensions of each part of the wheel. The image data stored in the frame memory 16 is output via the D / A converter 17 as needed and displayed on the monitor 18.

FIG. 7 shows a contour image of a wheel tread in which the image data stored in the frame memory 16 is displayed on the monitor 18, and FIG. 8 shows an image of the wheel inner side surface. In FIG. 7, the point apart from the flange end surface by a fixed distance is designated as Am point, and the point separated from the Am point by a fixed distance in mm is designated as Bm point. The tip of the flange is pointed to Cm. Ψm is calculated by calculating the gradient of the Am point, and βm is calculated by calculating the distance from the flange end surface to Bm.
Γm can be calculated by calculating the distance from the flange tip portion Cm to Am.

Next, in FIG. 8, the distance δm from the flange tip to the reference line can be calculated. The optical axes are aligned so that the line of the strip-shaped light emitted from the inner side surface of the wheel and the line of the strip-shaped light emitted from the tread surface of the wheel coincide with the straight line connecting the wheel center and the outer peripheral surface of the wheel. Since the image input timing of is matched with the image input timing of the wheel tread, the wheel diameter is calculated by subtracting γm calculated in FIG. 8 from δm calculated in FIG. 7 and adding the reference diameter N of the wheel. The wheel diameter αm can be calculated. However, as shown in FIGS. 7 and 8, in the image data stored in the frame memory, the image is distorted compared to the actual tread shape due to the positional relationship between the illumination device, the imaging device, and the wheels. In the above shape measurement, it is necessary to correct this distortion. A method for correcting the actual dimensions of each part of the wheel based on the image data of the tread portion input by the imaging device will be described below.

FIG. 9 shows the arrangement of equipment for imaging an image of the tread surface of a wheel. The plane formed by the strip light is L, the plane perpendicular to the central axis of the image pickup device 7 is C, and the planes L and C are formed. angle,
That is, the inclination angle of the imaging device 7 is θ. The coordinates on the frame memory are Xf and Yf planes, and the coordinates on the plane L are Xl and Y.
If the l coordinate and the coordinates on the plane C are the Xc and Yc planes, the coordinates xf and yf on the frame memory are converted to the coordinates x on the plane C.
The conversion into c and yc is performed by the formulas 1 and 2.

[0013]

[Equation 1]

[0014]

[Equation 2]

Here, xm0 and ym0 are x and y coordinates of Xm and Ym coordinates corresponding to origin coordinates of Xc and Yc coordinates. Further, Mx and My represent the length (mm) per pixel in the Xf and Yf directions in the frame memory screen, respectively. The conversion of the coordinates (xc, yc) on the C plane to the coordinates (xl, yl) on the L plane is performed by Expressions 3 and 4.

[0016]

[Equation 3]

[0017]

[Equation 4]

Here, h is the distance from the origin of the coordinates of the C plane to the image pickup device. From Equations 1 to 4, Equations 5 and 6 are used to obtain the actual coordinates of the wheel tread from the coordinates on the frame memory.

[0019]

[Equation 5]

[0020]

[Equation 6]

FIG. 10 shows the arrangement of equipment for image pickup on the inner side surface of the wheel. When the direction of the wheel axis and the axis of the image pickup device are the same, the coordinates of the image data on the frame memory and the actual coordinates are shown. The coordinates on the wheel are simply multiplied by Mh, and the relationship between the value of δm on the image data and the value of δ on the wheel is expressed by Equation 7.

[0022]

[Equation 7]

Here, Mh is a comparison coefficient between the unit length on the wheel and the unit length on the image memory. Next, a method of installing the above wheel measuring device for each of the left and right wheels and measuring the distance between the wheels on both sides will be described. FIG. 11 is a configuration diagram showing an embodiment in which a wheel measuring device is arranged for each of the left and right wheels, and the coordinates of the inner end surface of the left and right wheels are measured by the measuring device, and the coordinates of the inner end surface of each wheel are measured. The distance between the wheels can be calculated based on Further, in order to calibrate the positional deviation of the devices on both sides after installation, it is also necessary to periodically calibrate the wheels with a wheel width known.

[0024]

As described above, according to the present invention, the shape of the wheel tread surface and the shape of the inner side surface of the wheel are captured as a video signal, and the shape of the wheel tread surface, the wheel diameter dimension, or the distance between the wheels is determined from each image. Since the dimensions are calculated, it is possible to measure while moving the vehicle.

[Brief description of drawings]

FIG. 1 is a front view of a wheel showing essential parts of a tread surface and an inner side surface of a wheel according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a wheel measuring device showing an embodiment of the present invention.

FIG. 3 is an explanatory diagram showing irradiation positions of strip-shaped light that is irradiated onto the wheels according to FIG.

FIG. 4 is an explanatory diagram showing an arrangement of each device according to FIG.

5 is an explanatory diagram of an error caused by a change in wheel diameter according to FIG.

FIG. 6 is a block diagram showing a main part of FIG.

FIG. 7 is an explanatory diagram showing an image of the tread surface irradiated with the strip-shaped light according to FIG.

FIG. 8 is an explanatory diagram showing an image of the inner side surface of the wheel irradiated with the strip-shaped light according to FIG. 2;

9 is an explanatory diagram showing a relationship between a real plane according to FIG. 2 and a plane on a frame memory.

FIG. 10 is an explanatory diagram showing a positional relationship between an imaging device that captures an image of the inner side surface of the wheel according to FIG. 2, a light source, and the wheel.

FIG. 11 is a configuration diagram showing an embodiment of another invention.

[Explanation of symbols]

 1 wheel 2 wheel inner side surface 3 flange 4 tread surface 5 light source that illuminates the wheel tread surface with strip light 6 light source that illuminates the wheel inner surface with strip light 7 image pickup device that inputs the image of the wheel tread surface 8 image of the wheel inner surface Input imaging device 9 Image signal processing device 10 Photoelectric switch 11 Rail 12 Vehicle bogie 13,14 A / D converter 15 CPU 16 Frame memory 17 D / A converter 18 Monitor display

Claims (4)

[Claims] 1. A first light source for irradiating a first strip-shaped light on a line connecting a tread surface of a wheel and a central axis of the wheel, and a tread surface and a central axis of the wheel on an inner side surface of the wheel. A second light source that irradiates a strip-shaped second light on a line connecting the line, a first imaging device that captures an image of the tread surface that is illuminated by the first light, and a second light. A second image pickup device for picking up an image of the irradiated inner side surface of the wheel, and a wheel diameter measuring device for calculating the dimension of the tread surface of the wheel and the diameter of the wheel based on video signals obtained by the both image pickup devices. . 2. A photoelectric switch having a wavelength different from that of the first light and the second light is installed in accordance with the irradiation position of the first light and the second light, and a wheel detection signal from the photoelectric switch is provided. A feature is that the wheel image is input by detecting that the wheel arrives at a point where the first light radiated on the tread surface and the second light radiated on the inner side surface are aligned on the wheel in synchronization. The wheel measuring device according to claim 1. 3. A first light source for emitting a first strip-shaped light on a line connecting a tread surface of a wheel moving on a rail and a central axis of the wheel, and the tread surface and the wheel on an inner side surface of the wheel. The second strip-shaped second light is radiated on the line connecting the central axis of the
Image pickup device for picking up the image of the tread surface illuminated by the first light, which image is taken for the tread surface by the first light through the light source and the slit of the rail, which is arranged immediately below the rail. A second image pickup device for picking up an image of the inner side surface of the wheel illuminated by the second light, and the dimensions of the tread surface of the wheel and the wheel based on the video signals obtained by the two image pickup devices. Wheel measuring device that calculates the diameter. 4. The wheel measuring device is installed on both left and right sides,
A wheel measuring device, characterized in that the distance between the wheels on both sides is calculated by measuring the position coordinates of the flange end faces of the wheels on both sides.