Patent GB-347903-A (GB)
Title: Improvements in liquid dispensing apparatus
IPC: B67D7/16
Filed: 1930-05-16
Abstract: 347,903. Liquid meters. GILBERT & BARKER MANUFACTURING CO., Cold Springs Avenue, West Spring- field, Massachusetts, U.S.A. May 16,1930. No. 15120. Convention date, June 18, 1929. Addition to 308,756, [Class 69 (ii), Hydraulic presses &c.]. [Class 69 (ii).] Apparatus for dispensing petrol and other liquids in measured quantities comprises a pair of cylinders with connect. ed pistons, arranged so that one fills while the other discharges, the connection being resilient and adapted to be stressed by each piston towards the end of the filling stroke so as to initiate the subsequent discharge stroke. The valve mechanism is locked until the respective strokes are completed. Each of the measuring cylinders, 20, Fig. 3, contains a piston 21 having an air passage 22 controlled by a float 23. The upper limit of the piston stroke is controlled by the impact of an abutment 32 on an adjustable abutment in the cylinder head, and this, with the elastic connection, enables the desired quantity to be measured at each stroke. Each of the distributing valves comprises a ported disc 28, Fig. 14, in the base of the cylinder, having two diametrically opposite ports 41, and two similar discharge ports 42 communicate with a discharge passage 43. An inlet port is also formed in the base of each cylinder, the two inlet ports being connected to a common inlet passage. Each valve stem 46 carries an arm 47 connected together by a link 48 having a recess 49 to receive a roller 50, Fig. 10, on an arm 51 on a valve-operating shaft 39. Each valve is held on its seating by means which compensate for wear, comprising nuts 54, 55 which press the arm 47 against a ball bearing 57 below a sleeve 58 which bears against the casting 25. Packing 61 is compressed by a spring 59. The inlet passage passes through casting 53 and pipe 66 to a connection for the supply of liquid under pressure. The lower end of the pipe 66 carries a pair of arms 68 providing guides for the piston-rods 24. Each rod 24, Fig. 9, carries an arm 71 which receives a sliding rod 72 pressed upwards by a spring 27 until a head 74 abuts the arm 71. The two rods 72 are connected by a chain 26 passing over rollers 75. The pistons are therefore connected by chain 26, but when one piston is at the lower end of its stroke the other may continue to rise by yielding of the springs 27. The valve gear is locked by either of a pair of latches 34 released when the rising piston reaches the end of its stroke. The free end of each latch rests on top of a head 77 on a rod 78 carrying an adjustable abutment 83 in the path of the arm 84 which is integral with the arm 71, whereby the latch is lifted by the rising piston simultaneously with the engagement of the piston abutment 32 on the fixed abutment. The time of movement of the shaft 39 and thus the time of operation of the valves is also controlled by a locking-pin 36 Fig. 10, on the upper end of a sliding rod 85, which engages notches in the disc 38. The rod 85 carries a cross-bar 92 free to move between guide stops, 91, and pressed upwards with the rod by a spring 93. The ends of the bar 92 are engaged near the lower end of the piston stroke, by an arm 95 on the piston-rod. The valve lever 35 is moved when released, by a spring 29 coiled on a rod 96 which is free to slide in a collar 98 swivelled in the lever 35. Rod 96 is also pivoted, at its end, to the end of a lever 99 which is pivoted at 100, and the lever 99 is held stationary while the lever 35 is moved by the spring 29. As the piston moves upwards, the spring 103 is carried up and lifts a member 104 connected by a link 105 to a lever 106 mounted at its centre on a shaft coaxial with the shaft 177, which also carries a bifurcated lever 110. The latter engages at one end in a fork 112 of the lever 99, so that as the piston rises the lever 99 is swung and the spring 29 compressed. At one point of the movement of the lever 99 the parts are in such relative positions that the compressed spring 29 suddenly moves the lever 35 to its opposite position. During this movement, the lever 99 is held stationary by the engagement of one of its bifurcated ends 113 with a stop 114. After the parts have moved as above, the piston-rods may still move to the end of the stroke by compression of the springs 103 to release latch 34. The piston 21, Fig. 3, is provided with a cup leather 136 secured by a ring 137 and pressed outwards by a coil spring 140. The piston carries a baffle-plate 142 and is secured to the rod by a nut 32. The float 23 slides freely on the piston-rod and allows air to escape through port 22. Liquid is supplied to the pipe 66 by a hand-operated pump supported on the framing. The discharge is directed through an air-separating tank having a float-operated air-release valve. Means are preferably provided to drain the measuring cylinders when pumping ceases, through a pipe 168 connected to the inlet pipe 66, and thence to the supply tank. The quantity delivered is indicated by the number of operations of the lever 35, the register being operated from the shaft 177, Fig. 9. A Y-shaped lever 179 is pivoted at 180, and one arm carries a pawl 181 to actuate the ratchet 178. A holding pawl 182 is connected to the pawl 181 by a spring 183. The other arm is connected by a link 185 to a rod 187 extending into the path of the end of the lever 35, so that the shaft 177 is actuated at each movement of the lever 35. In normal operations when a piston reaches the lower end of its stroke the lock 36 is withdrawn and the valve mechanism released at this point, but its operation is not permitted until the rising piston has completed its upward stroke and released latch 34. The discharge stroke is initiated suddenly when the valves operate, by the springs 27. If, due to rapid pumping or other cause, the discharging piston lags behind the other, . and the latch 34 is prematurely released, the valve mechanism is still locked by the member 36.