# US 2019/0317007 A1 · Particle counting apparatus

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2019/0317007 A1
- Document ID: US20190317007A1
- Status: Published application
- Kind: A1
- Application number: 16/470,097
- Filed: 2017-09-12
- Published: 2019-10-17
- Earliest claimed: 2016-12-15
- Assignees: Horiba, Ltd.
- Applicants: HORIBA, Ltd.
- Inventors: Motoaki Hamada; Kazumasa Takemoto; Yoji Kawanami
- Web page: https://patentgrep.com/patent/US20190317007A1

## CPC

- G01N 15/12: by observing changes in resistance or impedance across apertures when traversed by individual particles, e.g. by using the Coulter principle
- G01N 15/131: {Details (G01N15/13 takes precedence)}
- G01N 33/48707: {by electrical means (G01N33/49, G01N33/493 take precedence)}
- G01N 33/49: Blood {(chemical methods for determining blood cell populations G01N33/5094; chemical analysis of blood groups or blood types G01N33/80)}
- G01N 2015/1024: {Counting particles by non-optical means}
- G01N 2015/133: {Flow forming}
- G01N 2015/135: {Electrodes}
- G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q)

## Abstract

An outside opening of each aperture of a plurality of counting chambers for performing particle counting based on the electric resistance method is connected to suction pump through a confluent piping. Liquid supplying part supplies an additional liquid to the counting chamber side after completion of counting of counting chamber, so that the liquid level of sample liquid of counting chamber will not descend to aperture or a predetermined liquid level.

## Claims

### Claim 1

A particle counting apparatus for counting particles in a sample liquid, comprising
a plurality of counting chambers each provided with an aperture and a pair of electrodes for counting particles based on the electric resistance method,
a suction pump, and
a liquid supplying part for supplying a liquid to one or more predetermined counting chambers,
wherein
the aperture of each of the plurality of counting chambers has an outside opening connected to the suction pump through a confluent piping, and
the liquid supplying part supplies a liquid to said one or more predetermined counting chambers or to a flow path on the predetermined counting chamber side than a confluent part in the confluent piping, after completion of counting in said one or more predetermined counting chambers, such that a liquid level of the sample liquid in said one or more predetermined counting chambers would not descend to the aperture or to a predetermined liquid level above the aperture.

### Claim 2 (depends on 1)

The particle counting apparatus according to claim 1, wherein
the plurality of counting chambers are cylindrically-shaped containers with a same inner diameter, and
a liquid level of the sample liquid in a counting chamber in which the counting is completed last is higher than the liquid level of the sample liquid in the one or more predetermined counting chambers at the time point when the sample liquid has been injected into each of the plurality of counting chambers.

### Claim 3 (depends on 1)

The particle counting apparatus according to claim 1, wherein
the plurality of counting chambers comprise a red blood cell counting chamber and a white blood cell counting chamber,
a counting chamber in which the counting is completed last is the red blood cell counting chamber, and
the one or more predetermined counting chambers are white blood cell counting chambers.

### Claim 4 (depends on 1)

The particle counting apparatus according to claim 1, wherein
the liquid supplied by the liquid supplying part is a diluent, and
the liquid supplying part comprises one or both of a diluent supplying device of the following (I) and a sampling-nozzle washer of the following (II):
(I) a diluent supplying device comprising a diluent supplying source, a diluent supply port provided in the one or more predetermined counting chambers, and a diluent supplying piping connecting the diluent supplying source and the diluent supply port
(II) a sampling nozzle washer comprising a diluent supplying source, a diluent outlet part accompanying a sampling nozzle provided in the particle counting apparatus, and a diluent supplying piping connecting the diluent supplying source and the diluent outlet part, wherein an outer surface of the sampling nozzle is washed while allowing the diluent to flow out on and drop from the outer surface.