Test strip evaluating instrument for multiple test strips

• US 5,143,694 A
• Filed: 12/04/1990
• Issued: 09/01/1992
• Est. Priority Date: 12/05/1989
• Status: Expired due to Term

• Current Assignee: Boehringer Mannheim GmbH (Roche Holding AG)
• Original Assignee: Boehringer Mannheim GmbH (Roche Holding AG)
• Inventors: List, Hans, Scheunert, Peter, Schafer, Dieter, Steeg, Klaus, Serrallach, Eugen, Laufenberg, Franz, Sattler, Stephan
• Primary Examiner(s): Housel, James C.
• Assistant Examiner(s): Le, Long V.
• Application Number:
  US07/622,053
• Time in Patent Office: 637 Days
• Field of Search: 422/65, 422/61, 422/63, 422/58, 422/66, 436/47, 436/48, 436/46, 436/43, 436/44
• US Class Current: 422/65
• CPC Class Codes: G01N 2035/00039 Transport arrangements specific to flat sample substrates, e.g. pusher blade
• CPC Class Codes: G01N 2035/00118 for multiple tests
• CPC Class Codes: G01N 35/00029 provided with flat sample substrates, e.g. slides G01N35/028 takes precedence
• CPC Class Codes: Y10T 436/11 Automated chemical analysis
• CPC Class Codes: Y10T 436/110833 Utilizing a moving indicator strip or tape
• CPC Class Codes: Y10T 436/112499 with sample on test slide
• CPC Class Codes: Y10T 436/113332 with conveyance of sample along a test line in a container or rack

Abstract

A test strip evaluating instrument is used for testing of multiple test strips, and has a transport and positioning device which transports the test strips at right angles to their longitudinal direction from a test strip feed area along a transport path to a disposal area. At least one measuring station with an optical measuring unit is arranged on the transport path. Rails, on which the test strips slide, run along the transport path. The test strips are transported in a step-wise manner by at least two rows of cam elements following one another in the transport direction, and these two rows of cam elements move synchronously with one another in a periodically recurring movement path. The handling of the test strips is facilitated without impairment of the measuring accuracy by the fact that the rails are longitudinally aligned as thin ribs in a disposable transport insert made of a thin plastic material, in which the cam elements engage from above between adjacent pairs of the rails of the transport insert, and in which a bearing element is provided for the tranport insert which supports the transport insert with a support surface in a central area lying between the test strip feed area and the disposal area. A rigid contact-pressure element is also provided, against which the test strip is pressed elastically from below during the measurement, and this contact-pressure element is disposed at the measuring station at a predetermined distance from the optical measuring unit.

Claims

1. A test strip evaluating instrument for conducting tests on a plurality of elongated test strips, said instrument comprising:

a transport and positioning means for transporting the test strips in a direction at generally right angles to a longitudinal extent of the test strips, from a test strip feed area along a transport path to a disposal area;

at least one measuring station having an optical measuring means disposed along said transport path for optically testing said test strips;

a disposable transport insert formed of a plastic material, said disposable transport insert completely covering a bottom portion of said transport path and having a plurality of spaced apart rails for slidably supporting the test strips, each of said plurality of rails extending in a direction which is generally parallel to a transport direction of said test strips and being formed as longitudinal ribs in said plastic material, wherein liquid from said test strips which contacts said disposable transport insert is prevented from contacting other areas of said instrument;

at least two rows of cam elements, each of said two rows of cam elements being aligned in said transport direction and being driven synchronously with each other in a periodically recurring movement path such that said two rows transport the test strips in a step-wise manner along said plurality of rails, wherein said two rows of cam elements engage the test strips from above and extend downwardly between adjacent ones of said plurality of rails;

a bearing means for supporting said transport insert, said bearing means having a support surface for supporting the transport insert in a central area of said transport insert which lies between said test strip feed area and said disposal area; and

a rigid contact-pressure means, having an underside against which the test strip is pressed elastically during measurement, provided at said measuring station, said rigid contact-pressure means being located at a predetermined distance from said optical measuring unit.

2. A test strip evaluating instrument according to claim 1, wherein said transport insert is composed of a thermoplastic plastics material.

3. A test strip evaluating instrument according to claim 1, wherein the wall thickness of said transport insert is less than 0.5 mm.

4. A test strip evaluating instrument according to claim 1, wherein said rails are disposed along a portion of said transport path corresponding to said measuring station.

5. A test strip evaluating instrument according to claim 4, wherein said rails of said transport insert are shaped such that said transport insert is elastically deformable in the vicinity of said measuring station in a direction normal to said transport path, and said support surface of said bearing means is substantially planar in said vicinity of said measuring station

6. A test strip evaluating instrument according to claim 1, wherein said transport insert comprises a trough disposed in the vicinity of said test strip feed area and in the vicinity of said disposal area.

7. A test strip evaluating instrument according to claim 1, wherein the distance between said rails is a multiple of a test field spacing between adjacent test fields located on the test strips, and wherein the test strips are guided along said transport path such that sections of said test strips lying between said test fields slide on said rails.

8. A test strip evaluating instrument according to claim 1, wherein said contact-pressure means at said measuring station is fixed to a test strip conveyor to which said cam elements are also fixed.

9. A test strip evaluating instrument according to claim 7, wherein said contact-pressure means includes a plurality of to said transport direction, said plurality of pegs being arranged such that they lie between adjacent ones of the test fields of the test strip when pressing on said test strip.

10. A test strip evaluating instrument according to claim 1, further comprising means for moving said bearing means periodically in an up and down movement which is normal to said transport path, and means for moving said cam elements periodically in a to-and-fro movement which is parallel to said transport path, said up and down and to-and-fro movements being coordinated to cause transport of said test strips in said step-wise manner along said transport path.

11. A test strip evaluating instrument according to claim 1, further comprising a lateral guide element having a front portion for positioning of the test strips along a longitudinal direction, said front portion impinging obliquely onto said transport path, and wherein said front part is not part of said transport insert.

12. A test strip evaluating instrument according to claim 1, wherein said transport insert is composed of polystyrene.

13. A test strip evaluating instrument according to claim 1, wherein the wall thickness of said transport insert is between 0.15 mm and 0.3 mm.