NMR spectrometer with gripping device for handling a sample bushing with outer groove

1. A nuclear magnetic resonance (NMR) spectrometer for investigating a liquid sample in a sample tube, the NMR spectrometer comprising:

a sample bushing surrounding the sample tube, said sample bushing having a bore into which one end of the sample tube is inserted with close tolerance, said sample bushing being substantially cylindrical with said bore extending along a cylinder axis thereof, said sample bushing having at least one groove fashioned externally on an outer surface of said sample bushing; and

a gripping device in cooperation with said sample bushing, said gripping device having at least three gripping fingers which engage said at least one groove of said sample bushing by pressing onto two outer edges of said groove in a closed configuration of said gripping device.

2. The NMR spectrometer of claim 1 , wherein said gripping device comprises four gripping fingers.

3. The NMR spectrometer of claim 1 , wherein each of said gripping fingers has a conical or rounded projection which is oriented radially inwardly towards said cylinder axis of said sample bushing in abutment with said two outer edges of said groove.

4. The NMR spectrometer of claim 1 , further comprising an expanding cone disposed inside said gripping device enabling upward and downward motion therein, said cone having a conical surface at a lower end thereof that accommodates spreading of said gripping fingers.

5. The NMR spectrometer of claim 1 , wherein said sample bushing defines a press fit into which the sample glass is insertable in a gas-tight manner.

6. The NMR spectrometer of claim 1 , wherein said sample bushing has a conical bore permitting introduction of an injection needle of a filling device.

7. The NMR spectrometer of claim 1 , further comprising a closing ball that seals said sample bushing in a liquid or gas-tight fashion.

8. The NMR spectrometer of claim 1 , wherein an outer diameter of the sample tube is less than 2 mm.

9. The NMR spectrometer of claim 8 , wherein an outer diameter of the sample tube is less than 1 mm.

10. The NMR spectrometer of claim 1 , wherein said sample bushing has an identification coding.

11. The NMR spectrometer of claim 10 , wherein said identification coding is a data matrix with data identifying the sample.

12. The NMR spectrometer of claim 1 , wherein said sample bushing has an alphanumerical marking, which can be visually read in determining a position where the sample glass is processed.

13. The NMR spectrometer of claim 12 , further comprising a container within which the sample is positioned by utilizing said marking.

14. The NMR spectrometer of claim 1 , wherein said at least one groove has a polygonal, rectangular or triangular cross-section.

15. The NMR spectrometer of claim 1 , wherein said at least one groove is formed as a continuous unbroken centering groove which extends around an entire periphery of said sample bushing.

16. The NMR spectrometer of claim 1 , wherein said sample bushing has several grooves.

17. The NMR spectrometer of claim 16 , wherein each one of said several grooves extends around an entire periphery of said sample bushing.

18. The NMR spectrometer of claim 1 , wherein said sample bushing has an outer diameter of 10 mm or less.

19. The NMR spectrometer of claim 18 , wherein said outer diameter is 3 mm to 8 mm.

20. The sample bushing of the NMR spectrometer of claim 1 , wherein said groove is formed such that said gripping fingers of said gripping device engage at least three groove locations distributed radially around said outer surface of said sample bushing, retaining said sample bushing while pressing onto said two outer edges of said groove when said gripping device is closed.