JPH0714862Y2 - Particle size distribution measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to an improvement of a particle size distribution measuring device for measuring a particle size distribution by light scattering.

[Prior Art] The particle size distribution measurement method by light scattering is used for the purpose of measuring the particle size, particle size distribution, high molecular weight, shape, etc. of fine particles having a size of micron to sub-micron, and (Particle) can be applied to any substance as long as it has a particle size range of micron to submicron, regardless of type and shape. This method is widely used in the fluid handling industry, that is, in the chemical industry including foods and pharmaceuticals, the steel industry, the mining industry, and the like for controlling the particle size of products and inspecting the status of manufacturing processes.

This particle size distribution measurement method by light scattering basically involves injecting laser light into a solution in which fine particles are dispersed, measuring the intensity change of light scattered by the particles by photon counting, and measuring the particle size from the intensity distribution. The diameter and the particle size distribution are obtained.

This method is used as a simple particle size distribution measuring method in that reproducible data can be obtained, there is no error caused by the operator, and measurement can be performed in a short time.

However, in the particle size distribution measuring device that has been conventionally used, laser light is projected from the horizontal direction through a condensing lens to a cell containing a measurement sample such as an emulsion or a suspension,
The scattered light from the particles in the measurement sample is received by the photomultiplier tube arranged such that the optical axis is located in the same horizontal plane as the optical path of the laser light, so that there are the following problems.

That is, in the above conventional measuring apparatus, (1) when mechanical vibration is applied, the optical axis of the reflected light reaching the photomultiplier tube is deviated, and a measurement error is generated due to the deviation. (2) Since the scattered light is received at an arbitrary angle by the photomultiplier tube, the photomultiplier tube can be rotated around the measuring device main body by the rotation drive system. It requires a large space around it.

[Problems to be Solved by the Invention] The problem to be solved by the present invention is to measure the particle size distribution by light scattering by a simple means of vertically guiding the light scattered by the measurement sample in the cell. Is to be able to be measured in a remarkably narrow range, and at the same time, it is possible to minimize the deviation of the optical axis due to the deflection and vibration of the equipment due to the weight of the photomultiplier tube.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a measuring device main body including a cell for storing a measurement sample such as an emulsion or a suspension, and a condensing lens in the cell. In the particle size distribution measuring device comprising a laser light source for projecting laser light from a horizontal direction through the photomultiplier tube for receiving scattered light from particles in the measurement sample, in the measuring device body, in the cell Providing a reflective surface that directs scattered light from the measurement sample vertically upwards,
A light guide tube having a plurality of pinhole slits is interposed between the reflecting surface and the photomultiplier tube, and the light guide tube and the photomultiplier tube connected to the light guide tube are connected to the measuring device body. The technical means of arranging vertically and around the cell together with the reflecting surface is adopted.

[Operation] When measuring the particle size distribution of a sample, a cell is filled with a measurement sample such as an emulsion or a suspension, and laser light projected from a laser light source is projected onto the measurement sample in the cell. Scattered light from the measurement sample is directed vertically upward by a reflecting surface set in a predetermined rotation position, enters the photomultiplier tube through a plurality of pinhole slits provided in the light guide tube, and is detected. .

[Example] FIG. 1 shows an example of the particle size distribution measuring device of the present invention.

The particle size distribution measuring device includes a measuring device body 1 including a quartz cell 2 for containing a measurement sample such as an emulsion or a suspension,
This cell 2 is provided with a laser light source 3 for projecting a laser beam from a horizontal direction through a condenser lens 4, and a photomultiplier tube for receiving scattered light from particles in a measurement sample on the measuring device body 1. A light guide tube 5 provided with 6 is provided upright.

The laser light source 3 is installed on the base 10 which is completely separated from the measuring device body 1, and therefore, the laser light source 3 is mainly used for maintenance and inspection of the entire device mainly including the measuring device body 1.
It can be easily done independently of.

The measuring device body 1 is provided with a light guide hole 13 for introducing laser light into the machine frame 12 at a position facing the laser light source 3 in the machine frame 12 having a short cylindrical shape installed on the base 11. At the same time, a pedestal 14 for arranging the cell 2 for accommodating the measurement sample such as emulsion or suspension is provided in the center of the machine frame 12. Also. A rotary base 17 supported by bearings 16 is mounted on the machine frame 12 so as to rotate around the central axis of the cell 2 arranged at the center thereof, and a support cylinder 18 mounted on the rotary base 17 is mounted on the rotary base 17. , A light guide tube 5 that supports a prism 20 having a reflecting surface 21 that directs scattered light from the measurement sample in the cell 2 vertically upward, and guides the scattered light reflected by the prism 20 upward.
Is erected. Inside the light guide cylinder 5, pinhole slits 22 and 23 are provided in the lower part and the intermediate part thereof, and a photomultiplier tube 6 for detecting the reflected light is attached to the upper part. Although not shown, a photon correlator for processing the output signal is connected to the photomultiplier tube 6. Light guide tube 5
The adjusting screw 27 provided in the lower part and the intermediate part of the is for adjusting the optical axes of the pinhole slits 22 and 23.

The rotary table 17 is rotated around the cell together with the prism 20 having the reflecting surface 21 and the light guide tube 5 to which the photomultiplier tube 6 is attached. Due to the rotation, the rotary table 17 has its periphery. A worm wheel 30 is fixed to a part of the worm wheel 30, and a worm 32 rotatably driven by a scattering angle setting handle 33 is meshed with the worm wheel 30.

In addition, each part of the measuring device body 1, for example, the turntable 17, the support tube 18, the light guide tube 5 and the like can be disassembled by screws to facilitate the adjustment of each part.

In the figure, reference numeral 35 denotes a lid attached on the cell 2.

When measuring the particle size distribution of the sample with the particle size distribution measuring device having the above configuration, the cell 2 is filled with a measurement sample such as an emulsion or a suspension, and the laser light projected from the laser light source 3 is guided. It is introduced into the machine frame 12 through the light hole 13 and projected onto the measurement sample in the cell 2. A prism 20 having a reflecting surface 21 for directing scattered light from the measurement sample in the cell 2 vertically upward.
The light guide tube 5 to which the photomultiplier tube 6 is attached is rotationally driven in advance by the scattering angle setting handle 33 and set at a predetermined position. Therefore, the scattered light reflected from the measurement sample in a predetermined direction is reflected by the prism. It is reflected by the reflecting surface 21 of 20 and guided upward, and is detected by being incident on the photomultiplier tube 6.

The two pinhole slits 22 and 23 provided in the optical path from the prism 20 to the photomultiplier tube 6 are different from those in the conventional case where they are provided in the horizontal direction.
Since it is not affected by the flexure, the structure can be simplified as a whole and the adjustment is easy. Further, since the optical path to the photomultiplier tube 6 is configured in the vertical direction, the space in which the device for receiving the scattered light at an arbitrary angle rotates becomes extremely narrow, and the measurement can be performed in a narrow range.

[Advantages of the Invention] According to the present invention described in detail above, the laser light source and the photomultiplier tube are arranged in the horizontal direction in the conventional particle size distribution measuring apparatus, while the scattered light from the cell is reflected by the prism. Since it is guided in the vertical direction via the, the particle size distribution measuring device can be used in a remarkably narrow range, and the deviation of the optical axis due to the deflection and vibration of the equipment due to the weight of the photomultiplier tube These can be suppressed to a minimum, and furthermore, these can be realized by an extremely simple means of guiding the light scattered by the measurement sample in the cell vertically upward.

[Brief description of drawings]

FIG. 1 is a side view showing the overall construction of an embodiment of the present invention,
2 is a moving plan view, FIG. 3 is an enlarged cross-sectional view of the measuring apparatus main body, and FIG. 4 is a cutaway plan view of the same portion. 1 ... Measuring device main body, 2 ... Cell, 3 ... Laser light source, 4 ... Condensing lens, 6 ... Photomultiplier tube, 21 ... Reflecting surface.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Takayoshi Kimura 3586 Yoshiwara, Ami-cho, Inashiki-gun, Ibaraki Tsumura Juntendo Engineering Department (72) Creator Jiro Koga Shimookubo, Urawa-shi, Saitama 255 (72) Creator Hajime Saito Three Hirosawa, Wako City, Saitama Prefecture, 2-1 RIKEN, Institute of Physical and Chemical Research (72) Inventor: Hiroshi Kato, 2-1 Hirosawa, Hirosawa, Wako, Saitama, Institute of Physical and Chemical Research (56) References: JP-A-61-155839 (JP, A) JP-A-62-70735 (JP, A)

Claims (1)

[Scope of utility model registration request] 1. A measuring device body provided with a cell for accommodating a measurement sample such as an emulsion or a suspension, a laser light source for projecting a laser beam in a horizontal direction through a condensing lens into the cell, and the measurement sample. In a particle size distribution measuring device having a photomultiplier tube for receiving scattered light from particles inside, in the measuring device main body, provided with a reflecting surface for directing scattered light from the measurement sample in the cell vertically upward, A light guide tube having a plurality of pinhole slits is interposed between the reflecting surface and the photomultiplier tube, and the light guide tube and the photomultiplier tube connected to the light guide tube are connected to the measuring device body. A particle size distribution measuring device characterized in that the particle size distribution measuring device is arranged vertically and rotatably around the cell together with the reflecting surface.