Chemical analyzer

• US 5,089,229 A
• Filed: 11/22/1989
• Issued: 02/18/1992
• Est. Priority Date: 11/22/1989
• Status: Expired due to Term

• Current Assignee: IDEXX Laboratories Incorporated
• Original Assignee: Vettest SA
• Inventors: Placensia, Armand, Heidt, Thomas, Will, Henry, Rhodes, Greydon
• Primary Examiner(s): Warden, Robert J.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US07/441,451
• Time in Patent Office: 818 Days
• Field of Search: 422/64, 422/63, 422/82.05, 436/46, 436/54
• US Class Current: 422/64
• CPC Class Codes: G01N 2035/00049 for loading/unloading a carousel
• CPC Class Codes: G01N 2035/00079 Evaporation covers for slides
• CPC Class Codes: G01N 2035/00237 Handling microquantities of analyte, e.g. microvalves, capillary networks
• CPC Class Codes: G01N 2035/00376 Conductive heating, e.g. heated plates
• CPC Class Codes: G01N 2035/00752 bar codes
• CPC Class Codes: G01N 2035/1034 Transferring microquantities of liquid
• CPC Class Codes: G01N 35/00029 provided with flat sample substrates, e.g. slides G01N35/028 takes precedence
• CPC Class Codes: G01N 35/00594 Quality control, including calibration or testing of components of the analyser
• CPC Class Codes: G01N 35/00712 Automatic status testing, e.g. at start-up or periodic
• CPC Class Codes: G01N 35/025 having a carousel or turntable for reaction cells or cuvettes
• CPC Class Codes: G01N 35/10 Devices for transferring samples or any liquids to, in, or from, the analysis apparatus, e.g. suction devices, injection devices G01N35/0099 takes precedence
• CPC Class Codes: G01N 35/1004 Cleaning sample transfer devices
• CPC Class Codes: Y10T 436/112499 with sample on test slide
• CPC Class Codes: Y10T 436/119163 with aspirator of claimed structure

Abstract

A chemical analyzer includes a transport mechanism having a rotatable turntable adapted to hold a plurality of reagent test slides, a sample metering device, an incubator or temperature controller, a reflectometer and associated electronics and software. The rotatable turntable preferably holds up to twelve slides about its circumference, which slides are loaded onto the turntable by an inserter mechanism. The turntable positions the reagent test slides under the metering device, which device deposits a predetermined amount of sample onto each slide. The turntable also carries the slides above a reflectometer. After testing has been completed, an ejector mechanism automatically removes the reagent slides from the turntable.

Claims

1. A chemical analyzer for analyzing reagent test slides onto which a fluid sample is metered, which comprises:

a rotatable turntable, the rotatable turntable being adapted to hold a plurality of test slides in a circular arrangement, the rotatable turntable including a top surface and a peripheral edge, and having formed in the top surface a plurality of recesses, the recesses being spaced apart from each other circumferentially about the turntable, each recess defining a receiving slot for receiving a test slide;

means for inserting slides onto the rotatable turntable, the slide insertion means being situated adjacent to the circumferential periphery of the rotatable turntable;

means for metering out a predetermined volume of fluid sample and for depositing the predetermined sample volume onto each test slide carried by the rotatable turntable, at least a portion of the same metering and depositing means being positioned in alignment with the test slides carried by the rotatable turntable;

a slide cover, the slide cover being positioned above the rotatable turntable and being at least partially rotatable relative to the turntable to cover and uncover test slides carried by the turntable, the slide cover being mounted on the top surface of the rotatable turntable and concentric therewith, the cover including a plurality of radially extending plate finger members, adjacent plate finger members defining a slot therebetween, each plate finger member including an opening formed through the thickness of said finger member, the slide cover further including a plurality of button members, each button member being at least partially received by a corresponding opening formed in the plate finger members, the slide cover further including means for biasing the button members, the biasing means extending a force on the button members to force the button members into the openings of the plate finger members;

a reflectometer, the reflectometer having a portion which is situated below the rotatable turntable and positioned in alignment with the test slides carried by the turntable, the reflectometer including at least one source of light of a predetermined wavelength, the light source being positioned with respect to the test slides carried by the turntable so as to direct light onto the test slides, and further including at least one light sensor, the light sensor receiving light reflected by the test slides carried by the turntable; and

means for removing test slides carried by the rotatable turntable, the slide removing means being situated in proximity to the rotatable turntable to engage the slides carried by the turntable and remove the slides.

2. A chemical analyzer as defined by claim 1, wherein the slide cover further includes internal sidewalls defining the openings of the plate finger members, each internal sidewall defining a respective opening being stepped inwardly of the opening to define a shoulder;

and wherein each button member includes a peripheral lip, the lips of the button members being adapted to rest on the cover opening shoulders.

3. A chemical analyzer as define by claim 1, wherein each of the button members extends through the thickness of the slide cover and includes a lower surface, the lower surface being adapted to engage a test slide carried by the rotatable turntable.

4. A chemical analyzer as defined in claim 3, wherein at least the lower surface of each button member is coated with an anti-fraction material.

5. A chemical analyer as defined by claim 3, wherein at least the lower surface of each button member is coated with an essentially inert and non-absorbing material.