JP3722743B2 - Particle detector and particle analyzer using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a particle detector. More specifically, in order to measure the particle size and number of powder particles such as fine ceramic particles, pigments, and cosmetic powders, a liquid containing particles is passed through a through-hole, and the liquid is detected based on a change in electrical impedance. The present invention relates to a particle detector that employs an electrical detection band method for measuring particles in the inside and also uses a so-called sheath flow method in which a particle-containing liquid flow is surrounded by a sheath liquid and flows into a through hole.
[0002]
[Prior art]
Prior arts related to this invention include a detection block having a through hole for particle detection, a first cell for supplying a particle-containing liquid to the through-hole in a sheath liquid, and containing particles that have passed through the through-hole. The second cell for receiving and discharging the liquid and the sheath liquid, the electrodes respectively provided in the first and second cells, and one of the first and second cells can be slidably supported to change the gap between them. There is known a sliding member, and a detection block is detachably held in a gap between the first and second cells and is watertightly connected to the first and second cells (for example, Japanese Patent Laid-Open No. Hei. 2001-33378).
[0003]
[Problems to be solved by the invention]
Conventionally, an electrical detection band method has been used to measure the particle size and number of blood cells in blood or industrial particles such as cement powder, latex, and toner. In the electrical detection zone method, a partition wall having one through hole is provided in an electrolyte solution, an electrode is disposed across the through hole, and a particle-containing liquid in which particles of interest are dispersed in the electrolyte solution is passed through the hole. Run through. When the particles pass through the through-hole, the electrical resistance changes instantaneously and a voltage pulse is generated. Since the pulse height reflects the particle volume, the sphere equivalent diameter of the particle can be measured with little influence on the shape, and the volume-based particle size of the sample particle can be obtained based on this result. Further, the number of particles can be obtained from the number of pulses.
[0004]
However, in the electrical detection zone method, the intensity of the detection signal varies depending on the passage position of the particles when passing through the through hole, and a plurality of particles that have passed close to each other are measured as one particle. There is a problem that particles after passing through the through hole stay around the through hole and cause noise. In order to solve these problems, a method using a sheath flow method has been conventionally employed. In the method using the sheath flow method in combination, the particle-containing liquid flow in the flow cell is surrounded by another liquid (sheath liquid), and the particle-containing liquid flow is narrowed down so that the particles in the liquid are at the approximate center of the through hole. By introducing it in a line, it is possible to obtain a granularity with less error.
[0005]
Therefore, in order to perform highly accurate detection in a particle detector using such a principle, it is necessary to maintain a high degree of coaxiality between the axis of the finely containing particle-containing liquid flow and the axis of the through hole. It is an indispensable requirement, and what kind of configuration has been realized has been an issue.
The present invention has been made in consideration of such circumstances. By adopting a configuration in which a plurality of components are connected by a through shaft, a particle detector having high coaxiality and easy assembly and disassembly can be obtained. It is to provide.
[0006]
[Means for Solving the Problems]
The present invention includes a plate-like member having a through hole for particle detection, a first cell that receives a particle-containing liquid and a sheath liquid and supplies the particle-containing liquid to the through-hole by being wrapped in a sheath liquid, and the through-hole. A second cell that collects and discharges the particle-containing liquid and the sheath liquid that have passed through; an electrode that is provided in each of the first and second cells; a plurality of shafts; and a fastening member that engages with each shaft. Each shaft penetrates the first and second cells arranged in a row with the plate-like members in a separable manner along the arrangement direction, and the fastening member fastens the first and second cells and the plate-like members in the arrangement direction. A particle detector is provided.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
The measurement target particles of the present invention include various biological particles such as blood cells and platelets in body fluids, inorganic particles such as latex and toner, organic powders for food additives, etc., and the measurement particle size ranges from about 1 to 100 μm. It is.
[0008]
The particle detector according to the present invention includes a plate-like member having a through hole for particle detection, a first cell that receives the particle-containing liquid and the sheath liquid and wraps and supplies the particle-containing liquid to the through-hole with the sheath liquid. The second cell that collects and discharges the particle-containing liquid and the sheath liquid that have passed through the through-hole, the electrodes that are respectively provided in the first and second cells, a plurality of shafts, and the shafts are engaged with each other. Each shaft includes first and second cells arranged in a row with the plate-like members detachably sandwiched along the arrangement direction, and the fastening members are plate-like with the first and second cells. The members are tightened in the arrangement direction.
[0009]
The first cell has a nozzle that receives the particle-containing liquid and injects it into the through hole, and a nipple that receives the sheath liquid and supplies the sheath liquid to the through-hole. The second cell has the particle-containing liquid and the sheath liquid that have passed through the through hole. The first and second cells and the plate member may be coupled so that the nozzle, the through hole, and the recovery pipe are coaxial.
[0010]
The plate-shaped member may include a disk-shaped pellet having the through hole.
The first cell includes a nozzle support portion having a nozzle for receiving the particle-containing liquid and spraying it to the through hole, and a first cell main body portion having a nipple for receiving the sheath liquid and supplying it to the through hole. One cell main body may be coupled to the plate member so that the nozzle and the through hole are coaxial.
[0011]
The nozzle support portion, the first cell main body portion, and the plate-like member may be water-tightly coupled to each other via packing.
The second cell has a recovery pipe holding part having a cylindrical recovery pipe for recovering and discharging the particle-containing liquid and the sheath liquid that have passed through the through hole, and a second nipple that receives the cleaning liquid and supplies it to the through hole. The recovery pipe holding part and the second cell main part may be coupled to the plate member so that the recovery pipe and the through hole are coaxial.
[0012]
The collection tube holding portion, the second cell main body portion, and the plate member may be water-tightly coupled to each other via the packings.
The tightening member may be composed of a nut that is screwed into at least one end of each shaft.
[0013]
The present invention will be described in detail below based on the embodiments shown in the drawings. This does not limit the invention.
1 is a side view of the particle detector of the present invention, FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1, FIG. 3 is a cross-sectional view taken along the line BB of FIG. FIG.
[0014]
As shown in these drawings, the particle detector 1 includes a plate-like member 3 having a particle detection through hole 2 (FIG. 4), and a particle containing liquid supplied to the through hole 2 in a sheath liquid. 1 cell 4 and the 2nd cell 5 which collects and discharges the particle content liquid and sheath liquid which passed through penetration hole 2 are provided.
[0015]
The first cell 4 and the second cell 5 are respectively provided with electrodes 6 and 7. The electrode 6 is made of stainless steel and is also used as a sheath liquid supply nipple, which will be described later, and used as a cathode, and the electrode 7 is made of platinum and used as an anode.
Further, the particle detector 1 includes two shafts 8 and 9, and fastening members that engage with both ends of the shafts 8 and 9, that is, nuts 10 to 13 that are screwed to both ends.
[0016]
The shafts 8 and 9 penetrate the first cell 4 and the second cell 5 arranged in a line with the plate-like member 3 being separable from both sides along the arrangement direction. The nuts 10 to 13 fasten the first cell 4, the second cell 5, and the plate-like member 3 from both ends of the shafts 8 and 9.
[0017]
The first cell 4 includes a nozzle support portion 15 and a first cell body portion 16. The nozzle support portion 15 has a nozzle 14 that receives the particle-containing liquid and injects it into the through hole 2. The first cell body portion 16 includes a nipple 27 that receives the cleaning liquid and sprays it obliquely from below to the through hole 2, and a nipple (also used as a cathode electrode) 6 that receives the sheath liquid and supplies it to the through hole 2 and discharges the cleaning liquid. Have. The nozzle support portion 15 and the first cell main body portion 16 are coupled to the plate-like member 3 so that the nozzle 14 and the through hole 2 are coaxial.
[0018]
Further, the second cell 5 includes a recovery tube holding part 18 and a second cell main body part 20. The collection pipe holding unit 18 integrally includes a cylindrical collection pipe 17 that collects and discharges the particle-containing liquid and the sheath liquid that have passed through the through hole 2. The second cell main body 20 integrally includes a nipple 19 for receiving the cleaning liquid and spraying the cleaning liquid obliquely from below to the through hole 2 and a nipple 28 for discharging the cleaning liquid.
The recovery tube holding portion 18 and the second cell main body portion 20 are coupled to the plate member 3 so that the recovery tube 17 and the through hole 2 are coaxial.
[0019]
The nozzle support part 15 and the first cell main body part 16 are watertightly coupled via a ring-shaped packing 21, and the recovery pipe holding part 18 and the second cell main body part 20 are connected via a ring-shaped packing 22. And are watertight.
[0020]
As shown in FIG. 4, the plate-shaped member 3 includes a pellet 24 having a through hole 2 and two ring-shaped packings 25 and 26 sandwiching the pellet 24 from both sides inside a central opening 23. And the 1st and 2nd cell main-body parts 16 and 20 are watertightly connected with respect to the pellet 24 via packing 25 and 26, respectively.
[0021]
The nozzle 14 includes a tube connection portion 29 at the rear end, and the recovery tube 17 also includes a tube connection portion 30 at the rear end.
[0022]
The nozzle 14 is made of stainless steel and has an inner diameter of 0.2 mm, and the pellet 24 is made of artificial ruby and has a thickness of 1 mm. In addition, although the diameter of the through-hole 2 changes with the particle sizes of measurement object particle | grains, in the case of erythrocytes, it is 50-100 micrometers.
[0023]
The first and second cell main body parts 16 and 20, the nozzle support part 15 and the recovery pipe holding part 18 are all formed by injection molding a chemical-resistant thermoplastic resin polyetherimide.
[0024]
The nipple 27 is integrally formed with the first cell main body 16, and the nipples 19 and 28 are integrally formed with the second cell main body 20. The nozzle 14, the electrode / nipple 6 and the electrode 7 are press-fitted into the nozzle support part 15, the first cell main body part 16 and the recovery pipe holding part 18 after molding, respectively, and fixed with an adhesive.
[0025]
When disassembling the particle detector 1 configured in this manner, the nuts 10 and 12 and / or the nuts 11 and 13 are removed from the shafts 8 and 9, and the nozzle support portion 15, the recovery pipe holding portion 18, the first and What is necessary is just to extract the 2nd cell main-body parts 16 and 20 and the plate-shaped member 3 from the shafts 8 and 9 in the direction which is easy to extract.
[0026]
When assembling the particle detector 1, the nozzle support 15, the recovery tube holding portion 18, the first and second cell main body portions 16 and 20, and the plate-like member 3 are attached to the shafts 8 and 9 in FIGS. 2 and 3. The nuts 10 to 13 need only be screwed into both ends of the shafts 8 and 9 and tightened.
[0027]
As a result, the positioning of the shafts 8 and 9 makes the nozzle 14, the through hole 2 and the recovery pipe 17 coaxial with high accuracy, and the tightening action of the nuts 10 to 13 causes the nozzle support portion 15 and the first and second cells to be coaxial. The main body portions 16 and 20 and the pellet 24 are strongly bonded in a watertight manner. Therefore, assembly can be performed with good reproducibility and good quality.
[0028]
FIG. 5 is a fluid circuit diagram of a blood analyzer using the particle detector 1. In the figure, when the valves V1 and V2 are opened, a sample for measuring red blood cells is sucked into the flow path P from the sample chamber SC and stored by the negative pressure in the drainage chamber WC1.
[0029]
When the valves V1, V2 are closed and the valves V3, V4, V5, V6 are opened, the diluent is supplied from the diluent chamber DC to the nipples 27, 19 as a cleaning liquid by positive pressure, and is sprayed to the through-hole 2, and the first and second The second cells 4 and 5 are cleaned and air bubbles are removed, and discharged from the nipples 6 and 28 to the drain chamber WC1.
[0030]
When the valves V3, V4, V5 and V6 are closed and the valve V7 is opened, the diluent is supplied as a sheath fluid from the diluent chamber DC to the nipple 6 as a sheath fluid, and passes through the through hole 2 and the recovery pipe 17 to drain the fluid chamber. It is discharged to WC2. As a result, a sheath liquid flow passing through the through hole 2 is formed.
[0031]
When the syringe pump CP is operated in the discharge direction in this state, the sample stored in the flow path P is pushed out and ejected from the nozzle 14 to the through hole 2. The ejected sample is wrapped in the sheath liquid, passes through the through-hole 2, and is discharged to the drain chamber WC2 through the recovery tube 17.
[0032]
When the sample is wrapped in the sheath liquid and passes through the through-hole 2, a change in impedance between the electrode 6 (FIG. 3) and the electrode 7 (FIG. 2) is measured by a measurement unit (not shown). When the measurement is completed, the syringe pump CP is stopped. Then, the valve V8 is opened, and the residual sample in the sample chamber SC is discharged to the drain chamber WC1.
[0033]
Next, the valves V1, V2, V8, and V9 are opened, and the diluent is supplied as a cleaning liquid from the diluent chamber DC to the sample suction channel, the sample chamber SC, the syringe pump CP, and the nozzle 14, and after a predetermined time, the valves V1, V2 , V8, V9 are closed to finish the cleaning.
[0034]
【The invention's effect】
According to the present invention, positioning is performed by penetrating the shaft through a plurality of parts constituting the particle detector, so that the particle detector can be easily assembled with high accuracy and reproducibility.
[Brief description of the drawings]
FIG. 1 is a side view of a particle analyzer according to the present invention.
FIG. 2 is a cross-sectional view taken along the line AA in FIG.
FIG. 3 is a cross-sectional view taken along the line BB in FIG. 2;
4 is an enlarged view of a portion C in FIG. 2. FIG.
FIG. 5 is a fluid circuit diagram of a blood analyzer using the particle analyzer of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Particle detector 2 Through-hole 3 Plate-shaped member 4 1st cell 5 2nd cell 6 Electrode 7 Electrode 8 Shaft 9 Shaft 10 Nut 11 Nut 12 Nut 13 Nut 14 Nozzle 15 Nozzle support part 16 1st cell main-body part 17 Recovery pipe 18 Collection pipe holding part 19 Nipple 20 Second cell main body part 21 Packing 22 Packing 23 Opening 24 Pellet 25 Packing 26 Packing 27 Nipple 28 Nipple 29 Tube connection part 30 Tube connection part

Claims (8)

A plate-like member having a through hole for detecting particles, a first cell that receives a particle-containing liquid and a sheath liquid and wraps and supplies the particle-containing liquid to the through-hole with a sheath liquid, and contains particles that have passed through the through-hole. A second cell that collects and discharges the liquid and the sheath liquid; electrodes provided in the first and second cells; a plurality of shafts; and a fastening member that engages each shaft. The first and second cells and the plate-like member arranged in a row with the plate-like members being separable are penetrated along the arrangement direction, and the fastening member is arranged in the arrangement direction of the first and second cells and the plate-like member. Tightened particle detector. The first cell has a nozzle for receiving the particle-containing liquid and spraying it to the through-hole and a nipple for receiving the sheath liquid and supplying it to the through-hole, and the second cell has the particle-containing liquid and the sheath liquid that have passed through the through-hole. 2. The particle detection according to claim 1, further comprising a tubular collection pipe for collecting and discharging the first and second cells and the plate member so that the nozzle, the through hole, and the collection pipe are coaxial. vessel. The particle detector according to claim 1, wherein the plate-like member is provided with a disk-like pellet having the through hole. The first cell includes a nozzle support portion having a nozzle that receives the particle-containing liquid and sprays it into the through hole, and a first cell main body portion having a nipple that receives the sheath liquid and supplies the sheath liquid to the through hole. The particle detector according to claim 1, wherein the one-cell main body is coupled to the plate member so that the nozzle and the through hole are coaxial. The particle detector according to claim 4, wherein the nozzle support portion, the first cell main body portion, and the plate-like member are water-tightly coupled to each other via packing. The second cell has a recovery tube holding portion having a cylindrical recovery tube that recovers and discharges the particle-containing liquid and the sheath liquid that have passed through the through hole, and a second nipple that receives the cleaning liquid and supplies it to the through hole. 2. The particle detector according to claim 1, comprising a cell main body, wherein the recovery pipe holding part and the second cell main part are coupled to the plate member so that the recovery pipe and the through hole are coaxial. The particle detector according to claim 6, wherein the recovery tube holding portion, the second cell main body portion, and the plate-like member are water-tightly coupled to each other via packing. A particle analyzer using the particle detector according to claim 1.

Images