GB624484A - Improvements in pulsators - Google Patents

Abstract

624,484. Cow milkers. SVENSKA AKTIEBOLAGET GASACCUMULATOR. March 31, 1947, Nos. 8656 and 8657. Convention dates, April 1, 1946 and Feb. 28, 1947. [Class 84] In a pulsator having a body in which move two mechanically coupled valves under the control of a diaphragm, the low pressure source is connected to a passage 15 leading to a teat cup through chamber 11, past valve 4 and through passage 18, whilst the vacuum is applied to a diaphragm chamber 10 through passage 17. At the same time a passage 16 leading to the other teat cup is connected to atmosphere by way of chamber 14, past valve 6 to chamber 12. The diaphragm chamber 9 is connected to the passage 16 by way of passage 21, the labyrinth passage 20 and passages 18, 19. The passage 20 delays the build-up of the pressure differential on the diaphragm 7 owing to the frictional resistance offered to the passage of the air by this labyrinth passage. At a given pressure differential the valves move downwards reversing the pressures on the teat cup passages and causing the cycle of operations to reverse. The rate of pulsations is determined by varying the cross-sectional area of the labyrinth passage by squeezing a resilient closure member 22 into the channel 20. Specification 334,146, [Class 84], is referred to.