GB1213421A - Improvements in or relating to cleaning devices - Google Patents

Abstract

1,213,421. Cleaning pipes. LINSON INSTRUMENT AB. 4 Dec., 1968 [6 Dec., 1967] No. 67644/68. Heading F2N. An arrangement for cleaning an elongated member of substantially uniform cross-section, e.g. the take off tube 19 of a transfer device 17 used in a liquid-sample analysis apparatus, comprises a collar 25 having a bore 26 therethrough and adapted to encircle an axial portion of the tube 19 in radially spaced relation to define, between the walls of the bore and the tube 19 an annular space 27, means for relatively displacing the collar 25 and the tube axially over a length of the tube to be cleaned, and a suction conduit 30 connected to the bore 26 between the ends thereof. Suction in the conduit 30 causes fluid to flow around the tube 19 through the annular space 27 and in to the conduit 30 to entrain any loosely adhering matter on the exterior of the tube 19. Two sample carriers 13, 14 are advanced step-by-step in synchronism, along a support surface 12 each carrier holding a series of sample tubes 15, 16 respectively. During each best period a post 23 descends to insert the tube 19 of a probe 18 into the sample tube 15 at the take-off position suction being applied to a tube 21 attached to the probe 18 to suck up a measured quantity of the sample. The post 23 is then raised and rotated to locate the tube 19 above a sample tube 16 the measured quantity of the sample in the probe 19, with a measured quantity of conditioning liquid supplied through the tube 21, being ejected into the tube 16, the conditioning liquid washing out the interior of the probe. The bore 27 communicates with a recess 31 which may be supplied with a wash-liquid 32 delivered through a passage 34 and a conduit 63. When the tube 19 is withdrawn from the sample tube 15 suction at the conduit 30 draws liquid 32 from the recess 31 and air through the lower end of the annular space 27 to carry off any sample residues adhering to the outer surface of the tube 19 through the suction conduit 29. If the wash liquid is supplied continuously the probe tube 19 is subjected to a similar treatment as it descends into a tube 15. Alternatively, the wash liquid may be supplied only during the upward movement of the probe, or, be entirely dispensed with so that air is drawn through the annular space during upward, and downward, movement of the probe.