GB926132A - Improvements in or relating to apparatus for taking samples of liquids - Google Patents

Abstract

926,132. Sampling liquids. WRIGHT HARGREAVES ENGINEERING CO. Ltd., and H. A. JOB Ltd. Aug. 25, 1959 [Aug. 25, 1958; Nov. 12, 1958], Nos. 27148/58 and 36310/58. Class 106 (5). Apparatus for taking samples from batches of liquids, in which means 10, 11 for withdrawing a liquid sample from a batch of the liquid, and for supplying the sample to a container 17 are responsive to two control valves 22, 23, the valve 22 being responsive to the presence of a container in the receiving position and the second valve, which is manually operable, being effective only if a container has actuated the valve 22. As applied to sampling milk from weigh-bowls in which individual batches of milk are weighed before being discharged therefrom for processing, the sample container 17 is placed on a platform 16 and thereby, against the action of a spring 20, depresses a shaft 18 connected to the table so as to operate the valve 22 connected in a compressed air circuit. In order to dispense a sample of milk from the weigh-bowl into the container, the manually-operable valve 23 is actuated which causes compressed air to be fed through a reversing valve 28 to one end of a double-acting ram 11, the ram-rod being connected to a piston within a cylinder 10. Movement of the latter piston draws milk from the weigh-bowl through a pipe 9 into the cylinder and, at the end of the stroke, a valve 30 is operated which reverses the valve 28 and thereby directs the air to the other end of the ram causing the piston to force the milk out of the cylinder 11, most of the milk returning to the weigh-bowl and the remainder being forced via a pipe 12 through the nozzle 15 into the container 17. The operation of the reversing valve 28 also directs the air supply through a pipe 32 and a further reversing valve 33 so as to actuate a ram 34 connected to a valve 35 and thereby discharge the contents of the weigh-bowl; a valve 50 is located in the pipe 32 in order, if desired, to prevent the weighbowl being discharged so as to permit a second sample to be taken therefrom. At the end of the dispensing stroke of the cylinder 10, a valve 40 is actuated so as to cause low-pressure air to be fed via a filter 41 through the pipes 9, 12 in order to completely drain the system. Further valves 26, 27, 51, 53 are provided for bypassing certain parts of the air circuit in order to permit cleaning liquid to be fed through the various components normally in contact with the milk. The apparatus, as shown, may be duplicated so as to take samples from two weigh-bowls, one apparatus being effective while the other is inoperative.