Liquid analyzer

• US 4,964,971 A
• Filed: 04/12/1988
• Issued: 10/23/1990
• Est. Priority Date: 04/14/1987
• Status: Expired due to Fees

• Current Assignee: Werner H. Riemann
• Original Assignee: Werner H. Riemann
• Inventors: Riemann, Werner H.
• Primary Examiner(s): Kaplan, G. L.
• Application Number:
  US07/180,459
• Time in Patent Office: 924 Days
• Field of Search: 204/401, 204/403, 204/409, 204/411, 204/412, 204/416
• US Class Current: 204/403.06
• CPC Class Codes: G01N 27/28 Electrolytic cell components
• CPC Class Codes: G01N 27/4035 Combination of a single ion-sensing electrode and a single reference electrode G01N27/406 and G01N27/413 take precedence

Abstract

The invention relates to an analyzer for liquids with at least one module (10) including a measuring line (14) having a reference electrode (16) and at least one measuring electrode (18). Measuring pads (48) borne by a carrier (80) can be pressed onto the measuring line; when out of contact therewith, they can be moved to and fro. The carrier may be elongated and adapted for sliding along a guiding rod (76). A spring-biased bar parallel thereto is pivotable and guides the carrier (80) as the latter is moved, e.g. when engaged by a tappet (68) of a motor-driven crank disk (66). A module chamber (30) is flow-connected to the measuring line (14) via a capillary aperture (28) in a flexible supply tube (26). Expediently, the capillary aperture (28) limits the leakage of an electrolyte in the chamber (30) to a maximum rate of 0.1 μl per 24 hours at ambient pressure and ambient temperature.

Claims

1. A device for electrochemically analyzing a body fluid which includes in combination

(a) a frame (52),

(b) module (10) on said frame (52), said module including a measuring line (14) containing a channel for the body fluid and at least one measuring electrode (18) and at least one reference electrode (16),

(c) a carrier (80, 46) containing a plurality of measuring pads (48),

(d) means for the controlled movement of said carrier (80, 46) towards said measuring line (14) and pressing it against said measuring line (14) and

(e) means for moving the said carrier (80) back and forth relative to the measuring line (24) when the measuring pads are out of contact with the measuring line (14).

2. A device according to claim 1 wherein said module (10) is positioned above the carrier (80) and in an inverted position relative to it.

3. A device according to claim 1 wherein electromechanical and/or electromagnetic means moves the carrier (80).

4. A device according to claim 1 wherein the frame (52) includes a bearing (70) for a guide bar (74) that is pivotable against the force of a spring (96) and that supports a carrier (80) adapted for stepwise shifting so as to singly move the measuring pads borne thereby towards and onto the measuring line (14).

5. A device according to claim 4 wherein the carrier (80) includes caps (88) which are adapted to slidably move along a rod (76) that is parallel to the guide bar (74).

6. A device according to claim 4 wherein the carrier (80) contains lateral recesses (86) for engagement by a tappet (68) of a motor-driven crank disk (66).

7. A device according to claim 6 wherein the crank disk (66) includes positioner means for establishing a defined initial position.

8. A device according to claim 1 wherein the carrier (80) includes an insert strip (46) having an array of measuring pads (46) that are adapted to hold liquid samples.

9. A device according to claim 8 wherein the carrier (80) includes confining means (98) for the strip (46).

10. A device according to claim 1 wherein each of the module electrodes (16, 18) has a connector (20) as well as a threaded section (22) and a probe portion (24) extending towards and onto the measuring line (14) and a chamber (30) in the module (10) is provided which is adapted to be sealed, to extend up to the measuring line (14) and to be flow-connected therewith via a capillary aperture (28).

11. A device according to claim 10 wherein the chamber (30) is arranged in the region of one electrode (16) in a direction transverse to the measuring line (14) and a supply tube (26) that includes the capillary aperture (28) extends through the chamber in a sealed manner.

12. A device according to claim 11 wherein the supply tube (26) is made of polyvinyl chloride and is adhesively attached to the chamber walls (34), the transitions between the supply tube and the tube and the chamber walls comprising adhesive seams (36).

13. A device according to claim 11 wherein the supply tube (26) passing through the chamber (30) is adapted to directly terminate the measuring line (14).

14. A device according to claim 10 wherein the chamber (30) is designed as a bore that is sealed at either end and extends across the measuring line (14).

15. A device according to claim 14 wherein the clear width (z) of the capillary aperture (28) is no larger than one tenth of the bore diameter (d).

16. A device according to the claim 15 wherein the clear width (w) of the chamber (30) is about ten times larger than the inner bore diameter (d) width is no larger than 1.0 mm.

17. A device according to the claim 10 wherein the chamber (30) is sealed by the reference electrode (16) on the one hand and by a semi-permeable disk (32) on the other hand.

18. A device according to the claim 10 wherein the capillary aperture (28) is dimensioned so that the rate of outflow of an electrolyte in the chamber (30) is smaller than 0.1 μ

l per 24 hours at ambient pressure and ambient temperature.

19. A device according to claim 1 wherein an outlet (40) joining the measuring line (14) is designed to include a pivotable bend.

20. A device according to claim 1 wherein there are plug connector means made up of the electrode connectors (20) associated with each electrode (16, 18).