JP6851234B2 - Imaging device for particle size distribution measurement - Google Patents

Description

The present invention relates to an imaging apparatus used for measuring the particle size distribution of a material.

In the process of manufacturing concrete in the construction of dams and the like, batcher plants and CSG (Cemented Sand and Gravel) mixing plants are used.
In these plants, it is necessary to understand the particle size distribution of materials for quality control of concrete. Therefore, it has been proposed to photograph the flowing material and measure the particle size distribution of the material based on the photographed result.

The image capturing device for measuring the particle size distribution includes a rectifying plate in which the material flows from the upstream side to the downstream side, a screen provided on the downstream side of the rectifying plate, and an imaging unit provided on the front side of the screen. (See, for example, Patent Document 1).
In the image capturing apparatus described above, a plurality of protrusions are formed on the surface of the straightening vane. In this way, the material flowing down the surface of the straightening vane comes into contact with the protrusions and is diffused. As a result, the material flowing down from the rectifying plate is rectified, so that the accuracy of particle size distribution measurement can be improved.

Japanese Patent No. 5908381

In the above-mentioned imaging apparatus, when the material has a high viscosity or the viscosity or the like adheres to the surface of the material, the material adheres to the protrusions and becomes a lump, which makes it difficult for the material to flow on the surface of the straightening vane. In some cases.

An object of the present invention is to provide an image capturing apparatus capable of solving the above-mentioned problems and allowing a material to smoothly flow down a straightening vane having a pin.

In order to solve the above problems, the present invention is an imaging device for measuring particle size distribution, and includes a straightening vane in which a material flows down from an upstream side to a downstream side. Further, the image capturing device includes a screen provided on the downstream side of the straightening vane and offset to the back side with respect to the straightening vane, and a photographing unit for photographing a material passing through the space on the front side of the screen. It has. A rotating pin is erected on the surface of the straightening vane, and the rotating pin is rotatably attached to the straightening vane about the axis.

In the imaging apparatus of the present invention, when the material flows down to the straightening vane, the material comes into contact with the rotating pin, so that the material is diffused and rectified. Then, since the rectified material is photographed by the photographing unit on the front side of the screen, the accuracy of the particle size distribution measurement performed based on the image of the material can be improved.

Further, in the imaging apparatus of the present invention, even if the material adheres to the upper side of the rotating pin, the material moves to the lower side of the rotating pin as the rotating pin rotates, so that the material easily peels off from the rotating pin. As a result, it becomes difficult for a lump of material to adhere to the rotating pin. Thereby, in the image capturing apparatus of the present invention, the material can be smoothly flowed down to the straightening vane having the rotating pin, and the material can be straightened.

In the image capturing apparatus for measuring the particle size distribution, when a plurality of the rotating pins are erected on the surface of the straightening vane, the material flowing down the surface of the straightening vane can be effectively diffused.

In the image capturing device for measuring the particle size distribution described above, it is preferable to provide a driving device for rotating the rotating pin about an axis. In this configuration, the material attached to the upper side of the rotating pin can be reliably moved to the lower side of the rotating pin. Further, the material attached to the rotating pin is easily peeled off from the rotating pin due to the centrifugal force generated by the rotation of the rotating pin.

In the image capturing apparatus for measuring the particle size distribution of the present invention, the rotation of the rotating pin makes it difficult for a mass of material to adhere to the rotating pin. As a result, the material can be smoothly flowed down to the straightening vane having the rotating pin, and the material can be straightened.

It is an overall block diagram which shows the particle size distribution measurement system which concerns on 1st Embodiment of this invention. It is a perspective view which shows the rectifying part which concerns on 1st Embodiment of this invention. It is an overall block diagram which shows the particle size distribution measurement system which concerns on 2nd Embodiment of this invention.

Embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
In the description of each embodiment, the same components will be designated by the same reference numerals, and duplicate description will be omitted.
In the present embodiment, a case where the imaging apparatus of the present invention is applied to a particle size distribution measuring system for measuring a particle size distribution of a material in a concrete manufacturing process will be described.

[First Embodiment]
As shown in FIG. 1, the particle size distribution measurement system 1 of the first embodiment has a particle size distribution of the material 3 based on an image capturing apparatus 2A for photographing the material 3 and an image of the material 3 obtained from the imaging apparatus 2A. It includes a calculation unit 60 for calculating a distribution. Further, the particle size distribution measurement system 1 includes a belt conveyor 10 that conveys the material 3 to the image capturing device 2A, and a hopper 80 that houses the material 3 that has passed through the image capturing device 2A.

The belt conveyor 10 is for supplying the granular material 3 containing the coarse-grained material (aggregate or the like) and the fine-grained material (earth and sand or the like) to the rectifying unit 20 described later.
The belt conveyor 10 includes pulleys 11 and 11 on the upstream and downstream sides, an endless belt 12 hung around both pulleys 11 and 11, and a motor (not shown) for rotating the pulley 11 on the upstream side. ing.

The image capturing device 2A includes a rectifying unit 20 provided on the downstream side of the belt conveyor 10, a screen 30 provided on the downstream side of the rectifying unit 20, an illuminating unit 40 illuminating the screen 30, and a space on the front side of the screen 30. It is provided with a photographing unit 50 for photographing the material 3 passing through the above.

As shown in FIG. 2, the straightening unit 20 includes two front and rear straightening vanes 21 and 22, and two left and right side walls 23 and 23. Both straightening vanes 21 and 22 and both side walls 23 and 23 are formed so as to form a square tubular duct.

As shown in FIG. 1, the front and rear straightening vanes 21 and 22 are arranged with normals of the front and rear planes in the horizontal direction. The front and rear straightening vanes 21 and 22 are arranged in parallel with an interval in the front-rear direction. The rear surface 21a of the straightening vane 21 on the front side and the front surface 22a (“surface” in the claims) of the straightening vane 22 on the rear side face each other with a space in the front-rear direction.

The upper end of the straightening vane 22 on the rear side is inclined toward the rear (see FIG. 2). Further, the upper end portion of the straightening vane 21 on the front side projects upward from the upper edge portion of the straightening vane 22 on the rear side.
As shown in FIG. 2, the left and right side walls 23 and 23 are attached to the side edges of the front and rear straightening vanes 21 and 22. The upper edges of the side walls 23, 23 are arranged below the upper edges of both straightening vanes 21 and 22.

As shown in FIG. 1, the upper opening 20a of the rectifying portion 20 is arranged below the end portion on the downstream side of the endless belt 12. The material 3 discharged from the endless belt 12 flows into the upper opening 20a of the rectifying unit 20.
Since the upper end portion of the rear rectifying plate 22 is inclined toward the rear and the distance between the front and rear rectifying plates 21 and 22 is widened on the upper side of the upper opening 20a, the material 3 enters the upper opening 20a. easy.
Further, since the straightening vane 21 on the front side projects upward from the upper opening 20a, it is possible to prevent the material 3 discharged from the endless belt 12 from jumping out to the front of the straightening vane 21 on the front side.

The material 3 that has flowed into the straightening unit 20 flows down along the rear surface 21a of the front straightening plate 21 and the front surface 22a of the rear straightening plate 22. Then, it flows down vertically downward from the lower opening 20b of the rectifying unit 20 in a straight orbit (track).

In the straightening unit 20 of the first embodiment, as shown in FIG. 2, three rotating pins 25 are erected on the rear surface 21a of the front straightening plate 21 and the front surface 22a of the rear straightening plate 22.
The rotary pin 25 is a member having a circular shaft cross section. As shown in FIG. 1, the axial direction of the rotating pin 25 is arranged perpendicular to the rear surface 21a of the front rectifying plate 21 and the front surface 22a of the rear rectifying plate 22. That is, the rotating pin 25 extends horizontally in the front-rear direction.

The front end portion 25a of the rotating pin 25 is inserted into a mounting hole 21b formed in the straightening vane 21 on the front side, and is pivotally supported by a bearing provided on the front surface 21c of the straightening vane 21 on the front side.
The rear end portion 25b of the rotating pin 25 is inserted into a mounting hole 22b formed in the rear rectifying plate 22, and projects toward the rear surface 22c of the rear rectifying plate 22.
The front end portion 25a and the rear end portion 25b of the rotating pin 25 are rotatably attached to the front and rear straightening vanes 21 and 22 around the axis.

In the first embodiment, as shown in FIG. 2, one rotating pin 25 is arranged above the rectifying unit 20, and two rotating pins 25, 25 are arranged below the rectifying unit 20.
The upper rotating pin 25 is arranged at the center of the rectifying unit 20 in the left-right direction, and the lower two rotating pins 25, 25 are arranged on the left and right sides of the upper rotating pin 25.

As shown in FIG. 1, the image capturing device 2A of the first embodiment is provided with a driving device 26 for rotating the rotating pin 25 about an axis.
The drive device 26 of the first embodiment is an electric motor, and is attached to the rear surface 22c of the straightening vane 22 on the rear side. Further, a drive device 26 is provided for each of the three rotating pins 25. Therefore, on the rear surface 22c of the rectifying plate 22 on the rear side, three driving devices 26 are arranged so as to be aligned with the positions of the three rotating pins 25.
The rear end portion 25b of the rotating pin 25 is connected to the output shaft of the drive device 26. As a result, the rotation pin 25 rotates about the axis in conjunction with the rotation of the output shaft of the drive device 26.

As shown in FIG. 1, the screen 30 is a flat plate provided on the downstream side of the rectifying unit 20 (see FIG. 2). The screen 30 is arranged parallel to both the straightening vanes 21 and 22. Further, the screen 30 is offset to the rear side (“back side” in the claims) with respect to the rear side straightening plate 22.
The screen 30 is arranged at a position away from the track (track) of the material 3 so that the material 3 flowing down from the lower opening 20b of the rectifying unit 20 does not come into contact with the front surface 30a of the screen 30. ..

The illumination unit 40 is a light source (light) that illuminates the front surface 30a of the screen 30, and is configured to irradiate the front surface 30a through a gap formed between the rear rectifying plate 22 and the screen 30. .. That is, the illumination unit 40 is arranged on the rear side of the material 3 that passes through the space on the front side of the screen 30.

The hopper 80 accommodates the material 3 that has passed through the space on the front side of the screen 30. The upper opening of the hopper 80 is located below the screen 30.

The photographing unit 50 is a camera that photographs the material 3 passing through the space on the front side (“front side” in the claims) of the screen 30 from the front side and outputs the photographing result to the calculation unit 60 described later. The photographing unit 50 is set to photograph the material 3 flowing vertically downward from the horizontal direction. That is, the image pickup surface of the image pickup device of the photographing unit 50 is arranged on a plane parallel to the vertical direction. As the photographing unit 50, a video camera or a digital camera capable of acquiring a digital image is suitable.

The calculation unit 60 is a computer including an input means, an output means, a CPU, a ROM, a RAM, and the like. The calculation unit 60 acquires an image of the photographing unit 50 and calculates the particle size distribution of the material 3 based on the image.

Here, a method of calculating the particle size distribution by the calculation unit 60 will be described.
The photographing unit 50 photographs the material 3 flowing from the upstream side to the downstream side with the front surface 30a of the screen 30 as a background. Then, the calculation unit 60 binarizes the photographing result and calculates the size of the material 3.

In the image capturing apparatus 2A of the first embodiment, the front surface 30a of the screen 30 is illuminated by the illumination unit 40 behind the material 3 passing through the space on the front side of the screen 30. Therefore, only the front surface 30a of the screen 30 becomes bright, and the material 3 is photographed as a black shadow. As a result, even if the material 3 has a pattern, the outer shape of the material 3 can be clearly recognized on the image.

Further, since the material 3 that has passed through the rectifying unit 20 passes through a position away from the screen 30, it is possible to prevent the front surface 30a of the screen 30 from being soiled by the material 3. As a result, when the photographing unit 50 photographs the material 3, the stains on the screen 30 are not photographed, so that the material 3 on the image can be accurately recognized.

Further, the material 3 flowing down from the rectifying unit 20 flows vertically downward in parallel with the image pickup surface of the image pickup device of the photographing unit 50, and the distance from the image pickup surface to each material 3 in the photographing region becomes constant. Therefore, the size of the material 3 can be accurately measured on the image.

In the image capturing apparatus 2A of the particle size distribution measurement system 1 as described above, as shown in FIG. 1, the material 3 flowing into the rectifying unit 20 flows vertically downward along the front and rear rectifying plates 21 and 22. Further, the material 3 comes into contact with the three rotating pins 25 and is effectively diffused. As a result, the materials 3 flow down in a rectified state without overlapping.
Then, since the rectified material 3 is photographed by the photographing unit 50 on the front side of the screen 30, the accuracy of the particle size distribution measurement performed based on the image of the material 3 can be improved.

Further, when the material 3 is made to flow into the rectifying unit 20, the rotating pin 25 is rotated about the axis by the driving device 26. In this way, even if the material 3 adheres to the upper side of the rotating pin 25, the material 3 moves to the lower side of the rotating pin 25 as the rotating pin 25 rotates, so that the material 3 peels off from the rotating pin 25. .. Further, the material 3 attached to the rotating pin 25 is peeled off from the rotating pin 25 by the centrifugal force due to the rotation of the rotating pin 25. As a result, the material 3 adhering to the rotating pin 25 can be reliably dropped.
Therefore, in the image capturing apparatus 2A, since the lump of the material 3 is unlikely to adhere to the rotating pin 25, the material 3 can be smoothly flowed down to the rectifying unit 20 having the rotating pin 25 to rectify the material 3.

When the material 3 is made to flow into the rectifying unit 20, the rotating pin 25 may be constantly rotated, but the rotating pin 25 may be rotated intermittently. Further, the rotary pin 25 may be rotated when the material 3 adheres to the rotary pin 25.

Although the first embodiment of the present invention has been described above, the present invention is not limited to the first embodiment and can be appropriately modified without departing from the spirit of the first embodiment.
For example, in the first embodiment, three rotating pins 25 are provided, but the number and arrangement of the rotating pins are not limited. Further, the thickness of the rotating pin 25 and the shape of the shaft cross section are not limited. The configuration of the rotating pin 25 is appropriately set according to the size, viscosity, and the like of the material 3.

Further, in the image capturing apparatus 2A of the first embodiment, the front and rear straightening vanes 21 and 22 are arranged vertically, but the upper portions of the front and rear straightening vanes 21 and 22 are arranged rearward with respect to the lower portion. It may be tilted so that the material 3 slides down the front surface 22a of the rear straightening vane 22.

Further, in the image capturing apparatus 2A of the first embodiment, two front and rear straightening vanes 21 and 22 are provided, but only the rear straightening vane 22 is provided, and the material 3 is the front surface of the rear straightening vane 22. It may be configured to flow down along 22a.

Further, in the image capturing device 2A of the first embodiment, the drive device 26 is attached to the rear surface 22c of the straightening vane 22 on the rear side, but the driving device 26 may be attached to the front surface 21c of the straightening vane 21 on the front side. .. In this case, the output shaft of the drive device 26 is connected to the front end portion 25a of the rotating pin 25.

Further, although the drive device 26 of the first embodiment is an electric motor, the configuration of the drive device 26 is not limited. Further, by connecting one drive device 26 and the plurality of rotation pins 25 by a drive transmission mechanism such as a belt mechanism, the plurality of rotation pins 25 may be rotated by one drive device 26.

[Second Embodiment]
Next, the image capturing apparatus 2B of the second embodiment will be described.
As shown in FIG. 3, the image capturing device 2B of the second embodiment has substantially the same configuration as the image capturing device 2A (see FIG. 1) of the first embodiment, and is not provided with the driving device 26. It's different.

In the straightening unit 20 of the image capturing apparatus 2B of the second embodiment, the front end portion 25a of the rotating pin 25 is inserted into the mounting hole 21b formed in the front straightening plate 21 and provided on the front surface 21c of the front straightening plate 21. It is pivotally supported by the bearing.
Further, the rear end portion 25b of the rotating pin 25 is inserted into a mounting hole 22b formed in the rear rectifying plate 22, and is pivotally supported by a bearing provided on the rear surface 22c of the rear rectifying plate 22.
The front end portion 25a and the rear end portion 25b of the rotating pin 25 are rotatably attached to the front and rear straightening vanes 21 and 22 around the axis.

In the rectifying unit 20 of the second embodiment, when the material 3 adheres to the upper side of the rotating pin 25, the rotating pin 25 shafts due to the weight of the material 3 and the impact when the material 3 collides with the rotating pin 25. It rotates around and the material 3 peels off from the underside of the rotating pin 25.

In the configuration in which the rotating pin 25 is freely rotated as in the image capturing apparatus 2B of the second embodiment, the configuration of the rectifying unit 20 can be simplified.

Although the second embodiment of the present invention has been described above, the present invention is not limited to the second embodiment, and can be appropriately modified without departing from the spirit of the first embodiment. Is.
For example, in the rectifying unit 20 of the second embodiment, blades may be provided on the outer peripheral surface of the rotating pin 25 so that the rotating pin 25 rotates when the flowing material 3 comes into contact with the blades.

1 Particle size distribution measurement system 2A Imaging device (first embodiment)
2B imaging device (second embodiment)
3 Material 10 Belt conveyor 20 Rectifier 20a Upper opening 20b Lower opening 21 Front rectifier 22 Rear rectifier 23 Side wall 25 Rotating pin 26 Driver 30 Screen 40 Lighting 50 Imaging 60 Calculation 80 Hopper

Claims (3)

A straightening vane where the material flows down from the upstream side to the downstream side,
A screen provided on the downstream side of the straightening vane and offset to the back side with respect to the straightening vane.
A photographing unit for photographing a material passing through the space on the front side of the screen is provided.
A rotating pin is erected on the surface of the straightening vane.
An image capturing apparatus for measuring a particle size distribution, wherein the rotating pin is rotatably attached to the straightening vane about an axis. The image capturing apparatus for measuring a particle size distribution according to claim 1.
An image capturing apparatus for measuring a particle size distribution, characterized in that a plurality of the rotating pins are erected on the surface of the straightening vane. The image capturing apparatus for measuring a particle size distribution according to claim 1 or 2.
An image capturing device for measuring a particle size distribution, characterized in that a driving device for rotating the rotating pin about an axis is provided.

Images