Apparatus for forming flattened sample flow for analyzing particles

• US 5,412,466 A
• Filed: 05/22/1992
• Issued: 05/02/1995
• Est. Priority Date: 07/26/1991
• Status: Expired due to Fees

• Current Assignee: Toa Medical Electronics Co., Ltd.
• Original Assignee: Toa Medical Electronics Co., Ltd.
• Inventors: Ogino, Shinichi
• Primary Examiner(s): Warden, Robert J.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US07/886,933
• Time in Patent Office: 1,075 Days
• Field of Search: 356/39, 356/72, 356/73, 356/318, 356/417, 356/246, 435/287, 435/291, 435/808, 209/3.1, 209/579, 209/906
• US Class Current: 356/246
• CPC Class Codes: G01N 15/1404 Handling flow, e.g. hydrodynamic focusing
• CPC Class Codes: G01N 15/1409 Handling samples, e.g. injecting samples
• CPC Class Codes: G01N 2015/144 Imaging characterised by its optical setup

Abstract

An apparatus for forming a flattened sample flow by passing a sample (liquid specimen) containing particle components such as blood and urine, in a broad, thin, flat flow. This apparatus is preferably used in an apparatus for analyzing particle images by emitting a strobe light to a sample flat flow, and taking the still images of the particle components. More specifically, the cross section of a measuring passage of a flow cell is rectangular with a side ratio of one to several times, with a shape that gradually narrows in width only in one direction of the lead-in passage, and the discharge port at the front end of the sample nozzle has a flat opening, or small discharge ports are arranged horizontally in a row. The decreasing direction of the width in the lead-in passage and the shorter diameter direction of the flat discharge port or the direction of the small discharge ports arranged horizontally in a row are matched. Besides, the cross section of the measuring passage of the flow cell is rectangular with a side ratio of one to several times, and sheath liquid dividing means disposed at the discharge port upstream side of the sample nozzle for dividing the sheath liquid into two symmetrical flows. The sample nozzle is placed so that the discharge port may be positioned at the converging region of the sheath liquid. For further enhancing the flatness of the sample flow, a sample nozzle having a flat discharge port, or plural discharge ports disposed horizontally in a row is used.

Claims

1. An apparatus for forming a flattened sample flow for analyzing particles, comprising:

a flow cell having a lead-in passage, a measuring passage contiguous to said lead-in passage, a sheath liquid feed port disposed to supply sheath liquid to said lead-in passage, a sample nozzle for discharging a sample from a sample discharge portion to said measuring passage, disposed across the flow of the sheath liquid in said lead-in passage, and a liquid discharge port for discharging liquid from said measuring passage;

sheath liquid dividing means disposed at the upstream side of said sample nozzle in contact with the sample nozzle so as to divide the sheath liquid symmetrically into two flows, wherein;

the cross section of said measuring passage is rectangular, and the ratio of the width of the long axial direction of said measuring passage to the width of the short axial direction of said measuring passage is in the range of 1 to 10;

said sample nozzle having an inner passage passing through said sample nozzle in the direction of said sample nozzle axis;

the sample discharge portion of the sample nozzle is composed of a plurality of discharge ports communicating with said inner passage;

the plurality of discharge ports are disposed midway of the sample nozzle and arranged in a row in the direction of the sample nozzle axis;

the direction at which said discharge ports are arranged coinciding with the long axial direction of said measuring passage; and

said sheath liquid dividing means is disposed so that the lateral projecting direction of said sheath liquid dividing means and the axial direction of the sample nozzle coincide.

2. An apparatus for forming a flattened sample flow for analyzing particles, comprising:

a flow cell having a lead-in passage, a measuring passage contiguous to said lead-in passage, a sheath liquid feed port disposed to supply sheath liquid to said lead-in passage, a sample nozzle for discharging a sample from a sample discharge portion to said measuring passage, disposed across the flow of the sheath liquid in said lead-in passage, and a liquid discharge port for discharging liquid from said measuring passage; and

sheath liquid dividing means disposed in contact with said sample nozzle, for dividing the sheath liquid into two symmetrical flows, at the upstream side of the sample nozzle, wherein;

the cross section of said measuring passage is rectangular, and the ratio of the width of the long axial direction of said measuring passage to the width of the short axial direction of said measuring passage is in the range of 1 to 10;

said sample nozzle having an inner passage passing through said sample nozzle in the direction of said sample nozzle axis;

the sample discharge portion of the sample nozzle is composed of a rectangular discharge port communicating with said inner passage;

the rectangular discharge port is disposed midway of said sample nozzle so as to open toward said measuring passage, so as to coincide the long axial direction of the rectangular discharge port with the long axial direction of said measuring passage; and

said sheath liquid dividing means is disposed so that the lateral projecting direction of said sheath liquid dividing means and the axial direction of the sample nozzle coincide.