Stepwise advancing rotary conveyor and installation for taking liquid samples incorporating such a conveyor

Claim 1

An installation for taking liquid samples from bottles (F) sealed by caps (O), characterized in that said installation comprises a stepwise advancing rotary conveyor (10) comprising a fixed base (12) having a horizontal upper face (12a) onto which issues a first injector (18) communicating with pressurized gas supply means (22), a rotary plate (24) resting by gravity on the upper face of the base and cooperating with said face by means (16, 26a) for centering the plate about a fixed vertical axis. said plate having a circular outer edge (26c, 28b), an upper face provided with receptacles (36) distributed in ring-like manner about said axis and a lower face (26b) defining with the upper face (12a) of the base a central support chamber (30), at least one passage (32) oriented in a direction inclined with respect to a radius through said axis being formed in the plate (24) in order to connect the central support chamber and the outer edge of the plate in order to ensure rotation of the latter when the supply means (22) are actuated, the plate having a weight such that the rotation is instantaneously stopped when the supply means are stopped, remote detection means (38, 42, 44) operatively associated with said plate for the remote detection of the presence of one of said receptacles (36) in a given angular position about said axis, and control means (122, 120) operatively connected with said detection means sensitive to signals supplied by the detection means (44) in order to control the stoppage of the supply means (22) when said one of said receptacles (36) is present in said angular position, the bottles being placed in receptacles (36) of said plate, and whereby sad installation also incorporates a fixed lateral gantry (40) supporting a vertical sampling needle (58) via means (64) for displacing said needle vertically between an upper position authorizing the rotation of the plate and a lower sampling position, in which the cap is perforated by the needle, and a chromatographic valve (70) having a plurality of inlets and equipped with a sampling loop (72), whereby said valve can occupy either a sampling position in which two first inlets (6,5) of said plurality of inlets, respectively communicating with the needle (58) and with a suction venturi (86), are interconnected across said loop (72), or a sample discharge position, in which two other inlets (2,3) of said plurality of inlets of the valve, communicating respectively with means (78) for ejecting a sample taken and with a sample discharge tube (80), are interconnected across said loop (72).