Patent GB-316988-A (GB)
Title: Improvements in the teat-cups of milking machines and the means of creating pulsations therein
IPC: A01J5/04
Filed: 1928-04-03
Abstract: 316,988. Pessell, R. C., and Petters, Ltd. April 3, 1928. Cow milkers. - A milking - machine is provided with teat cups which comprise freely flexible liners for the reception of the teats the interiors of such liners being intermittently subject to a part vacuum and the exteriors continuously subject to atmospheric or a plus pressure so that the liners are intermittently compressed on to the teats, ana the cups are so constructed that they maintain their hold on the teats in the absence of the part vacuum. The air pressure within the liners is controlled by one or more pulsator or interrupting devices disposed in the connections between the liners and apparatus for creating the part vacuum; thus, a pulsator may be arranged between a suction pump and a milk receptacle connected with the teat cups, and/or a pulsator may be disposed between the milk receptacle and the teat cups. As shown, a suction pump F and the teat cups B are connected with chambers c connected with, and through which the. milk passes on its way to, the milk receptacle C, and the valves C<3> controlling the chambers are subject to the action of the pump. A pulsator A is arranged between the pump and the chambers and the cups, or there may be a second pulsator in this position. The pulsator may comprise a member D which is movable within a cylindrical chamber under the action of links e<1>, a pivotally mounted disc e<2>, and the strap e of an eccentric E driven from the pump F, and is adapted to place a suction pipe f alternately in communication with conduits H. These conduits are fitted with control cocks h and, if desired, these cocks may be operated mechanically, as from the pump, so that they serve the purpose of the pulsator. In a further form of pulsator an apertured sleeve is movable within a cylinder to connect four nozzles alternately in pairs with suction, the nozzles being connected with the branch conduits J<1>. The sleeve has a second series of holes so that by turning the sleeve, say through 90‹, it is adapted to connect other pairs of nozzles alternately to suction. Besides having a pulsator for interrupting the suction, the apparatus may have valves for allowing air to enter the teat cups when the suction is cut off; thus, the member D may be arranged to open a valve-controlled part and admit air to that conduit H which is not in communication with suction. The teat cup comprises a flexible tube or liner b, Fig. 7, within a resilient helical frame. b<1> which has attached to its upper end a ring b<2> over which the end b<3> of the liner is folded while the lower end of the frame is secured to a ring b<4> having a reduced screw-threaded part b<5> and a further reduced end b<6> over which the lower end of the liner b is folded and secured by a cap b'. A resilient ring or collar K, for example of rubber or spirally wound wire, is arranged between the ring b<2> and the liner, and when in the form of a tube this ring K may be varied in size by inflation or deflation, or by making provision for admitting compressed air and or connecting to suction the ring may be made to expand and contract in a pulsating manner. Alternatively the lower part of the liner may be arranged within a metal &c. casing and the upper part disposed in a resilient spiral extension, and the liner may then be of such length that it can be folded over to such an extent as to enclose entirely the resilient extension, the enclosed space being connected with a source of compressed air for applying the continuous plus pressure to the outer surface of the line).. Or there may be a resilient extension at each end of the cup. Specification 323,762 is referred to. According to the second Provisional Specification (1) the free end of the tube constituting the liner of the teat cup may be folded back outwardly over some or all of the coils of a frame in the form of a coil or spiral spring, and the space between the rubber walls then serves the same purpose as the outer space of an ordinary teat cup, and (2) instead of being folded during the assembly of the cup, the liner may be moulded or constructed with a permanent fold.