Abstract: While a large primary stream (24) of analytes flow from a chromatographic column (20) to containers of a receiver (108), small samples of the analytes are diverted for flow to a mass spectrometer (54) for analysis, by use of a transfer module (102). The transfer module includes a stator (110) and a rotor or shuttle (114). The shuttle has an aliquot passage (120) that initially lies in a first position where the primary stream flows through it so the aliquot passage receives a small sample. The shuttle then moves to a second position where the aliquot passage (at 122) is aligned with a pump (134) that pumps fluid out of the aliquot passage to the mass spectrometer.

Abstract: A sample inject valve system is described, which enables a modified sample injection valve to perform many functions that are required to inject a sample into a chromatographic column, to minimize the amount of laboratory table space previously occupied by equipment and to organize and minimize the number of tubular fluid connections. The modified valve includes a stator (70) with twelve passages (1-12) lying on a circle (74) centered on a rotor axis (76) and a rotor (72) with four channels (A, B, C, D) for connecting selected passages. The stator passages are spaced 30.degree. apart to lie at the twelve positions of a clock face. Each rotor channel has channel ends spaced by 30.degree. and with the ends of different but adjacent channels spaced apart by 60.degree..

Abstract: A valve that receives sample and solvent streams, and delivers slugs of different fluid samples separated by slugs of the solvent, to a detector. The valve includes a stator (140) having a central hole (40) and a circle of sample holes (51-54) and solvent holes (91-94). The valve also includes a rotor (150) with a first groove (162) that connects one of the sample or solvent holes to the central hole to flow to the detector. The first groove is wide enough and the space between adjacent supply holes is small enough, that as the first groove moves from one hole of the circle to the next, the groove becomes partially open to the next hole before it leaves the last hole to minimize the sudden increase in pressure along the flow to the detector.

Abstract: A single selection valve allows the selection of three or more alternate flow routes without any unswept volume along any of the routes. The selection valve has a rotor (22) that can pivot about an axis (30) on a stator (12), the stator having ports (1-8) generally lying on a port circle (54) that is centered on the axis and the rotor having channels (60, 62) on its front face that faces the rear of the stator. Each rotor channel has a radial groove (70) with a port end (72) lying on the port circle, and each channel has an arc groove (74) that connects to the radial groove and that extends substantially circumferentially along an arc circle (76) that is centered on the axis, but that has a smaller radius than the radius of the port circle.