JPS6015541A - Apparatus for measuring particle size distribution of particles - Google Patents

Abstract

PURPOSE:To enable accurate measurement of particle size distribution handily and quickly by irradiating particles dropping from a granulator or the like with a plane strobo light through a slit to take a still image of particles with a TV camera provided vertical to the plane light. CONSTITUTION:When particles 2 are dropped from a granulator, hopper or the like 1, a start signal is sent to a high-speed image processor 7 from a microcomputer 8. Receiving the signal, the processor 7 transmits a signal to a strobo controller 9 to irradiate the particles 2 with a plane strobo light A from a slit strobo light emitter 3. A semicircular image of each particle is taken with a TV camera 4 arranged vertical to the surface A and the image is displayed on a TV monitor via a camera controller 5 while the projection lengths of the particles are calculated, classified and accumulated with the processor 7. The results are transmitted to the computer 8 to compute the particle size distribution, average particle size and the like and the results are outputted to a printer 10 or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is for measuring the particle size distribution, particle diameter, etc. of a particle group, and relates to an apparatus that enables continuous measurement.

For example, it is necessary to measure the particle size, particle size distribution, etc. of particles granulated by a granulator or granular objects of various Ito-forms. As a means of measuring the shape, size, etc. of these particle groups,
Conventionally, methods such as sieving using a sieve are known,
It was extremely inefficient. Also known is a method of measuring the shape, size, etc. of a particle group using a strobe light emitting device and a television camera to capture a still image of the particle group. However, in this method using still images, since a large number of particle groups are imaged, the particles overlap each other, making it difficult to determine the size of each particle. Therefore, conventional methods using still images do not directly measure the particle group discharged from the granulator or hopper, etc.
There is a drawback that an appropriate alignment device must be used to align the particles at the same intervals before imaging.

The present invention has been made in view of the above-mentioned circumstances, and it illuminates a group of particles falling from a granulator, a hopper, etc. using a strobe light emitting device provided with a slit, and the light emitting device A television camera is used to image the illuminated particles, arranged in a direction almost perpendicular to the plane of the light that emitted and passes through the slit, and then image the particle group using a television camera. Based on this still image, the shape, particle size distribution, etc. The object of the present invention is to provide a particle group 1111 determination device that measures 1111 of particles.

The detailed contents of the measuring apparatus of the present invention will be explained below based on the following embodiments. 1 shows a granulator in which the granulated lacquer yarn group 2 is falling from the other granulator. 3 is a slit strobe light emitting device provided with a vertically elongated (long in the vertical direction) slit, and 4 is a +I4i A of the light emitted from the slit strobe light emitting device (the light that passes through the elongated slit travels approximately in a plane). A television camera is placed at a nearly right angle to the camera and focuses on this 100A beam. Furthermore, it is said [-
I:I is an angle that does not cause out-of-focus even at the periphery of the image with the right angle at the center. 5 is a camera controller; 6 is a TV monitor for viewing images taken by the TV camera 4; 7 is a high-speed image sensor; 8 is a microcomputer; Strobe controller, 10 hub linter.

In the measuring apparatus having the above configuration, a start signal is transmitted by the microcomputer 8 when the particle group 2 granulated by the granulator 1 is dropped as shown in the figure. Upon receiving this start signal, the high-speed image processor 7 sends a signal to the strobe controller 9, which causes the slit strobe light emitting device to emit light. The particle group 2 falling naturally from the granulator 1 is illuminated by this strobe light. At the same time, a signal is sent from the high-speed image processor 7 to the camera controller 5, and the camera controller 5 causes the television camera 4 to take an image.

The image of the particle group 2 at this time is, for example, as shown in FIG. That is, in FIG. 2, the system strobe light comes in the direction of the arrow, so that the half of each particle (the shaded area in the drawing) is illuminated and brightened, and this is imaged by the television camera 4.

The captured still image signal is sent to the television monitor 6 and displayed on it for observation. This signal from the 1￥p City Painting Team is simultaneously sent to the high-speed image processor 7.
Processing is performed here to calculate the horizontal projection length of each particle. The calculated projection lengths are classified into n-level classes according to their lengths. A high speed image processor 7 stores the number of particles in each class. In this manner, the high-speed image processor 7 classifies and accumulates data on particles within a certain field of view, and sends the results to the microcomputer 8.

The data sent to the microcomputer 8 is output to the printer 10 after calculating statistical values such as particle size distribution and average particle diameter.

As described above, since the measuring device of the present invention illuminates with the strobe light emitting device 1/l and images with a television camera, it is possible to image falling particles as a still image. In addition, the light emitting device is a slit strobe light emitting device equipped with a slit, and the television camera is placed at a position almost perpendicular to the direction of emission of the strobe light, so that only the focal plane of the television camera is irradiated with light. Illumination light is not irradiated to the particle group falling through out-of-focus positions before and after the particle group. Therefore, there is no possibility of erroneously training an out-of-focus particle. Since the images are irradiated in a half-moon shape, it is possible to separate horizontally overlapping images, and therefore, a high-speed image processor only needs to separate vertically overlapping images, which simplifies processing.

As a result of the above, there is no need to align the particle groups before dropping them, unlike in the conventional method.

In addition, in the examples, the solid particle group granulated in the granulator was described, but the measurement of other solid particle groups and the measurement of the droplet particle size distribution during urea granulation, etc. It can also be applied to measurements. Further, the plane of the planar strobe light can be set at any angle from vertical to horizontal.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing the configuration of a measuring device of the present invention, and FIG. 2 is a diagram showing a state in which a group of particles is illuminated with strobe light in the device of the present invention. 1... Granulator, 2... Particle group, 3... Slit strobe light emitting device, 4... Television camera, 5
...Camera controller, 6...Television monitor, 7...High-speed image processor, 8...
・Microcomputer-19...Stroboko"
Draw 'y-+ 10...pudding 2-8 out 9! Person: Hiroshi Mukai, Agent, Mitsubishi Chemical Industries, Ltd. - Figure 1■

Claims (1)

[Claims] A strobe light emitting device having a slit for illuminating a group of falling particles, and a strobe light emitting device arranged in a direction substantially perpendicular to the planar strobe light traveling through the slit to focus on the position of the particle group illuminated by the strobe light. and a television camera, the strobe light emitting device emits light to illuminate the particle group, and the particle size distribution is determined based on a still image of the particle group captured by the television camera. Particle size distribution measuring device.