Flow cell apparatus

• US 5,690,895 A
• Filed: 12/06/1996
• Issued: 11/25/1997
• Est. Priority Date: 01/26/1993
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Miyake, Ryo, Ishii, Masaharu, Ohki, Hiroshi, Yamazaki, Isao, Horiuchi, Hideyuki, Yabe, Ryohei, Sakuraba, Shinichi, Matsumoto, Masaetsu
• Primary Examiner(s): SNAY, JEFFREY R
• Application Number:
  US08/761,143
• Time in Patent Office: 354 Days
• Field of Search: 356/39, 356/72, 356/73, 356/246, 422/63, 422/67, 422/68.1, 422/82.05, 422/73, 422/81, 422/111, 422/119, 250/461.1, 250/461.2
• US Class Current: 422/73
• CPC Class Codes: G01N 15/1404 Handling flow, e.g. hydrodynamic focusing
• CPC Class Codes: G01N 2021/0346 Capillary cells; Microcells
• CPC Class Codes: G01N 21/05 Flow-through cuvettes G01N21/09 takes precedence; handling fluid samples G01N1/10

Abstract

A flow cell apparatus, useful in an apparatus for measuring particles suspended in a liquid, comprises a sample liquid, supply device, a sheath liquid supply device, a flow cell which has a flow passage passing through a transparent measuring portion, and a nozzle for causing the sample liquid, from the supply device to flow in the flow passage of the flow cell. The nozzle has at least one discharge port which is disposed in the flow passage in a spaced relation from the inner wall of the flow cell flow passage. The sheath liquid supply device causes the sheath liquid to flow around the nozzle discharge port and surround the sample liquid flow to form a sheath flow. The flow passage of the flow cell and the nozzle are so formed as to ensure a sample liquid flow of a fixed width through the measuring portion. A stable sample flow having a fixed width can be formed in the measuring portion even when the flow is at a high velocity, and particles in the sample liquid can efficiently be photographed with high accuracy.

Claims

1. A flow cell apparatus, comprising;

sample liquid supply means for supplying a sample liquid to be measured;

sheath liquid supply means for supplying a sheath liquid;

flow cell means for defining a flow passage, said flow cell means having a transparent measuring portion providing an unobstructed view of said flow passage in at least one transversal direction thereof, said flow passage having a substantially constant width in a direction perpendicular to said direction of the unobstructed view;

nozzle means provided in fluid communication with said sample liquid supply means for causing the sample liquid to flow into said flow passage of said flow cell means, said nozzle means having at least one discharge port disposed in said flow passage in a spaced relation from an inner wall thereof;

said sheath liquid supply means being in fluid communication with said flow passage of said flow cell means at a position upstream of said at least one discharge port of said nozzle means with respect to a flow of the sample liquid to cause the sheath liquid to flow around said at least one discharge port and surround the sample liquid flow from said at least one discharge port to form a sheath flow; and

guides provided at said at least one discharge port for regulating a width of the sample liquid flow in at least the direction perpendicular to said direction of the unobstructed view in said measuring port, wherein said guides are arranged so as to provide the sample liquid flow in said flow passage with a constant width at least at a portion of said flow passage at which said transparent measuring portion is provided.

2. The apparatus according to claim 1, wherein said guides are disposed on opposite sides of said at least one discharge port in a widthwise direction of said flow passage for guiding the sample liquid from said at least one discharge port to form a stable flow of the constant width.

3. The apparatus according to claim 1, wherein said sample liquid supply means is disposed separately from said flow cell means and is formed to be selectively connected to said flow cell means in a sealed manner.

4. The apparatus according to claim 1, wherein said sample liquid supply means and said sheath liquid supply means are capable of changing a quantity of said sample liquid and that of said sheath liquid supplied to said flow cell means, respectively.

5. The apparatus according to claim 1, wherein said sheath liquid supply means is provided with a waste liquid port for discharging a liquid for cleaning said flow passage in said flow cell means.

6. The apparatus according to claim 1 further comprising holder means for holding said flow cell means, wherein said flow cell means is attached to said holder means at both ends of said flow passage, said sheath liquid supply means includes an annular sheath liquid supply portion which is sealingly connected to one of said ends of said flow passage and mounted on said holder means, and said nozzle means is inserted into said flow passage of said flow cell means through said sheath liquid supply portion.

7. The apparatus according to claim 1 further comprising means for varying any one of a flow rate of the sample liquid, a flow rate of the sheath liquid and a shape of said discharge port of said nozzle means to change a velocity of the sample liquid flow and a cross sectional shape thereof.

8. The apparatus according to claim 1 further comprising means for varying at least one of a flow rate of the sample liquid, a flow rate of the sheath liquid and a shape of said at least one discharge port of said nozzle means to independently change a velocity, the width and a height in the unobstructed view direction of the sample liquid flow.

9. The apparatus according to claim 1, wherein said flow cell means further includes means provided upstream said measuring portion for narrowing the sheath flow in the unobstructed view direction of said measuring portion to increase a velocity of the sample liquid flow in the sheath flow and reduce a thickness of the sample liquid in the unobstructed view direction to form a flat flow.

10. The apparatus according to claim 9, wherein said sheath flow narrowing means is set to increase the velocity of the sample liquid flow to 1000 mm/second or higher.

11. The apparatus according to claim 9, wherein said sheath flow narrowing means constructed to reduce the thickness of the sample liquid for photographing particles of the sample liquid through a microscope in said measuring portion.

12. The apparatus according to claim 9, wherein said sheath flow narrowing means comprises a portion of said flow passage having a height in the unobstructed view direction, which height is gradually decreased downstream.

13. The apparatus according to claim 9, wherein said nozzle means further includes means for changing the width of the sample liquid flow.

14. The apparatus according to claim 9, wherein said guides are disposed on opposite sides of said at least one discharge port in a widthwise direction of said flow passage for guiding the sample liquid from said at least one discharge port to form a stable flow of the constant width.

15. The apparatus according to claim 1, wherein said nozzle means further includes means for changing the width of the sample liquid flow in accordance with a measuring range in said measuring portion.

16. The apparatus according to claim 15, wherein said flow width changing means comprises a plurality of discharge ports of said nozzle means, which are individually and selectively communicated with said sample liquid supply means.

17. The apparatus according to claim 15, wherein said flow width changing means includes at least one discharge port of said nozzle means, which at least one discharge port is formed to be variable in opening width.

18. The apparatus according to claim 15, wherein said guides comprise fixed guide plates which are respectively provided on both sides of said at least one discharge port in a widthwise direction of said flow passage, and wherein said means for changing the width of the sample liquid flow includes means for changing a flow rate of the sample liquid flow and said fixed guide plates each of said guides being formed to enable the sample liquid to flow over said fixed guide plates when said sample liquid is provided at greater than a predetermined flow rate.

19. The apparatus according to claim 15, wherein said flow width changing means comprises said guides which are movable guide plates provided on both sides of said at least one discharge port in a widthwise direction of said flow passage, respectively.

20. The apparatus according to claim 1, wherein said nozzle means further includes means for changing a shape of the sample liquid flow.

21. The apparatus according to claim 20, wherein said flow shape changing means includes said at least one discharge port of said nozzle means, which at least one discharge port is variable in opening shape.

22. The apparatus according to claim 20, wherein said flow shape changing means includes the nozzle means which nozzle means mounted for rotation about a longitudinal axis thereof in said flow passage.

23. The apparatus according to claim 20, wherein said flow shape changing means comprises a plurality of discharge ports of said nozzle means, which are arranged both in a widthwise direction of said flow passage and in the unobstructed view direction of said measuring portion and are individually and selectively communicated with said sample liquid supply means.

24. The apparatus according to claim 20, wherein said flow shape changing means are a plurality of discharge ports of said nozzle means, which each have different shapes of openings and are individually and selectively communicated with said sample liquid supply means.

25. The apparatus according to claim 1, wherein said nozzle means is detachably fastened to said flow cell means.

26. The apparatus according to claim 25, wherein said nozzle means is sealingly mounted to said flow cell means with said at least one discharge port of said nozzle means inserted into said flow passage.

27. The apparatus according to claim 1, wherein said flow passage of said flow cell means has a substantially rectangular cross section, a height of which in the unobstructed view direction of said measuring portion is smaller than the width of said flow passage.

28. The apparatus according to claim 27, wherein said guides comprise a pair of elongated, stationary guide plates respectively provided on both sides of said at least one discharge port in the widthwise direction of said flow passage, and said guide plates are inclined inwardly toward each other in a manner that the sample liquid smaller than a certain flow rate is regulated into a fixed width and the sample liquid more than the certain flow rate flows over said guide plates to form a wider flow.

29. The apparatus according to claim 27, wherein said at least one discharge port of said nozzle means is defined by a central portion and two side portions which are movable with respect to said central portion to change a width of opening of said at least one discharge port, and said nozzle means further includes actuator means for moving said two side portions.

30. The apparatus according to claim 27, wherein said nozzle means includes an elastic tube of a circular cross section connected to said sample liquid supply means, a pair of pressing plates movably provided adjacent to said elastic tube to change the cross section of said elastic tube, and actuator means for moving said pressing plates.

31. The apparatus according to claim 27, wherein guides comprise a pair of elongated guide plates respectively provided for pivoting movement on both sides of said at least one discharge port in the widthwise direction of said flow passage to change a distance between ends of said guide plates to regulate the width of the sample liquid flow, and wherein actuator means for driving said guide plates are further provided.

32. The apparatus according to claim 27, wherein said at least one discharge port of said nozzle means has a substantially rectangular cross section, said nozzle means is mounted in said flow passage for rotation around a longitudinal axis of said nozzle means, and said nozzle means further includes actuator means for rotating said nozzle means and wherein said guides comprise a pair of stationary guide plates respectively provide on shorter side portions of said at least one discharge port.

33. The apparatus according to claim 27, wherein said nozzle means includes a first nozzle having a substantially rectangular cross section and a second nozzle disposed in said first nozzle said first and second nozzles including first and second discharge ports, respectively, and wherein said guides comprise a pair of stationary guide plates respectively provided on both sides of said discharge port in the widthwise direction of said flow passage, said second nozzle having a substantially rectangular cross section which is smaller than that of said first nozzle, and said second nozzle being provided, respectively on both sides said second discharge port thereof in the widthwise direction of said flow passage, with a pair of stationary guide plates which are smaller in size than said guide plates of said first nozzle, and wherein said first nozzle selectively communicates with said sample liquid supply means to change a shape of the sample liquid flow passing through said measuring portion.

34. The apparatus according to claim 33, wherein said second nozzle is movably mounted to protrude from said first nozzle into said flow passage along a longitudinal axis of said first nozzle, and said nozzle means further includes actuator means for moving said second nozzle.

35. The apparatus according to claim 27, wherein said nozzle means has three discharge ports arranged in the widthwise direction of said flow passage, and the two discharge ports at opposite sides of said three discharge ports selectively communicate with said sample liquid supply means to change the width of the sample liquid flow.

36. The apparatus according to claim 35, wherein said guides comprise a first pair of elongated guide plates respectively provided on both sides of said nozzle means in the widthwise direction of said flow passage to extent substantially in parallel to the direction of the sample liquid flow, and a second pair of elongated guide plates respectively provided on both sides of a central discharge port of said three discharge ports in the widthwise direction of said flow passage, said second pair of elongated guide plates extending substantially in parallel to the direction of the sample liquid flow, and said first guide plates being larger in length in the direction of the sample liquid flow than said second guide plates.

37. The apparatus according to claim 27, wherein said nozzle means includes a plurality of discharge ports disposed around a common longitudinal axis, and said plurality of discharge ports selectively communicate with said sample liquid supply means to vary a combination of said discharge ports for discharging the sample liquid to change a shape of the sample liquid flow passing through said measuring portion.

38. The apparatus according to claim 37, wherein said discharge ports each have a substantially square cross section and are arranged adjacent to one another to collectively define a larger square.

39. The apparatus according to claim 37, wherein said nozzle means includes a central discharge port disposed on said common longitudinal axis, the other discharge ports are situated around said central discharge port at equal intervals, and said central discharge port and said other discharge ports each have an identical circular cross section.

40. The apparatus according to claim 27, wherein said flow passage of said flow cell means includes a parallel flow passage portion which passes through said measuring portion and has a height substantially constant in the unobstructed view direction, and a flow contraction passage portion which is disposed upstream said parallel flow passage portion and has a height gradually decreased toward said parallel flow passage portion.

41. The apparatus according to claim 40, wherein the height of said parallel flow passage portion is set in accordance with a depth of focus of a microscope to be used in measurement.

42. The apparatus according to claim 40, wherein said discharge port of said nozzle means has a substantially square cross section, and said guides comprise a pair of elongated guide plates respectively provided on both sides of said discharge port in a widthwise direction of said flow passage to extend substantially in parallel to a direction of the sample liquid flow.

43. The apparatus according to claim 40, wherein said discharge port of said at least one nozzle means has a substantially flat, elongated cross section, a height of which in the unobstructed view direction of said measuring portion is smaller than the width of said flow passage.

44. The apparatus according to claim 40, wherein said flow passage of said flow cell means is further provided with a deceleration flow passage portion, which is disposed downstream said parallel passage portion and increased in height gradually from said parallel flow passage portion.

45. The apparatus according to claim 44, wherein said flow passage of said flow cell means is further provided with another parallel flow passage portion which has a substantially constant height and is disposed upstream said flow contraction passage portion.

46. The apparatus according to claim 40, wherein said flow passage of said flow cell means is defined by plate-like members joined together, said flow contraction passage portion is defined by a pair of flow contracting plates, and said flow contracting plates each have a trapezoidal cross sectional shape in a direction of the sample liquid flow and are secured in said flow passage to face each other.

47. The apparatus according to claim 46, wherein said plate-like members are transparent.

48. The apparatus according to claim 40, wherein said nozzle means has three discharge ports arranged in a widthwise direction of said flow passage, the two discharge ports at opposite sides of said three discharge ports being selectively communicated with said sample liquid supply means to change the width of the sample liquid flow.

49. The apparatus according to claim 48, wherein said guides comprise first and second pairs of elongated guide plates, said two discharge ports being provided at their outermost sides in the widthwise direction of said flow passages with said first pair of elongated guide plates, respectively, which each extend substantially in parallel to the sample liquid flow, a central one of said three discharge ports being provided at both sides thereof in the widthwise direction of said flow passage with said second pair of elongated guide plates, respectively, which each extend substantially in parallel to the sample liquid flow, and wherein each of said first pair of elongated guide plates is larger in length in the direction of the sample liquid flow than each of said second pair of elongated guide plates.

50. The apparatus according to claim 40, wherein guides comprise a first pair and a second pair of elongated guide plates respectively provided on both sides of said at least one discharge port in the widthwise direction of said flow passage, said second pair of elongated guide plates being smaller in length in the direction of the sample liquid flow than said first pair of elongated guide plates and inclined inwardly toward each other to form the sample liquid flow of a small width, and said first guide plates being disposed outside the respective second guide plates and extending substantially in parallel to the direction of the sample liquid flow to form the sample liquid flowing over the second pair of elongated guide plates into a flow of a constant width.

51. The apparatus according to claim 50, wherein each of said second pair of elongated guide plates is tapered in a downstream direction.