Patent GB-624902-A (GB)
Title: Improvements in pulsators
IPC: A01J5/12
Filed: 1947-03-31
Abstract: 624,902. Milking machines. SVENSKAAKTIEBOLAGET GASACCUMULATOR. March 31, 1947, Nos. 8654 and 8655. Convention dates, April 1, 1946 and Feb. 12, 1947. [Class 84] In a pulsator for use in a milk ing machine, the valve system which alternately connects one or more pipes to two chambers ir which differing relative pressure: exist, is controlled by a timing mechanism which actuates directly the valves, so producing changes o: pressure in the system, with the result that the other valve is reversed, so allowing the cycle o: operations to continue. In one form, the pulsator comprises a central body 1, 2 in which a pistor 5 is sealed by diaphragms 3, 4, the piston carrying disc valves 6, 7 which, depending on their position, co-operate with seats 8, 9, in heads 10, 11 secured to the centre portion, to seal openings 12, 13 which are connected to a source of low pressure. The operation of the pulsator, commencing when the port 12 is sealed and the port 13 open, is that the passage 21 which is connected to a teat cup is suuject to vacuum through port 13, the chamber 17, and opening 20., whilst the passage 19, also connected to a teat cup, is connected to the atmosphere through opening 30, air chamber 24, passage 26, past the diaphragm 29 and the passage 33. Since the chamber 16 is also connected to the passage 19 through opening 18, the diaphragm chamber 36 is compressed and air is forced past a throttling valve 43 to act on the diaphragm 42 which is secured to the piston 5 and the body 1, 2. Similarly, diaphragm chamber 37, mounted in a chamber 17, or being subjected to vacuum, expands, and the pressure acting on the top of diaphragm 42 decreases as air flows past the throttling valve 4 to the diaphragm chamber 37. As this pressure differential on the diaphragm 42 builds up, the diaphragm moves the piston 5 so closing port 13 and opening port 12, so that the passage 19 is now connected to the low pressure; this causes the diaphragm 29 to move to the seat 31 and in so doing to connect the chamber 17 and, in consequence, the passage 21 to the atmosphere, and the cycle of operations is recommenced. In a second form, passages 60, 61 are connected to teat cups and lead back into chambers 58, 59 which can either be connected to a source of low pressure or to atmosphere, depending on the position of a valve 54. When the valve disc 53 rests on the seat 56 of the chamber 59 passage 61 is connected to atmosphere and passage 60 is connected by passage 57 to the low-pressure source. Air at atmospheric pressure passes from the passage 61 through a throttling valve 66 to the upper side of a diaphragm 62, the diaphragm chamber being connected to the low-pressure source since a rod connecting the diaphragm 62 to the piston 54 is a loose fit in the casing so that a passage is formed around the rod connecting chambers 63 and 58. As the differential pressure on the diaphragm builds up, the diaphragm moves the valve 54, opening the passage 61 to the low-pressure source. Movement of the valve removes the abutting collar 75 from beneath the diaphragm valve 67, which moves so as to connect,the passage 60 with the atmosphere, and the cycle of operations recommences.