GB311858A - Improvements in or relating to apparatus for delivering measured volumes of fluids - Google Patents

Abstract

311,858. Morrison, A. E., and Morrison, A. C. March 7, 1928. Fixed-chamber apparatus. -Liquid under pressure is measured from a cylinder 1 containing a piston 4. Ports 2, 3 communicate with adjoining cylinders 9, 10 having openings 11, 13 leading to the supply and discharge pipes, respectively; while a further port 12 connects the cylinders 9, 10. A spring- pressed hollow valve-piston 14 covers the opening 13 during the filling operation but leaves free the port 12 whereby the liquid has access to both sides of the piston by the passages 11, 9, 12, 15, 3 and 11, 9, 2. Owing to the differing areas exposed above and below the piston 4 the latter rises. On the completion of the filling stroke, the valve 14 is lifted by a lever 20, thus uncovering the discharge 13 and covering the port 12. The liquid pressure is now operative by way of the port 2 only. Discharge proceeds until a tappet 35 on the piston-stem 5 presses on one of a number of projections 34 adjustably fixed to the rod 32, To the lower end of the rod 32 is connected a bell-crank lever 28 having forked' arms embracing a cross-pin from a spring-pressed catch 24 for retaining the valve 14 in the position to which it has been lifted by the lever 20. Depression of the rod 32 therefore releases the valve 14 and stops delivery. The rod 32 is supported vertically in a bracket 25, and the arms 34 are adjusted so that a predetermined quantity is delivered when one of the arms is depressed by the tappet 35. A radial arm 36 with a depending spring-pressed pin for entering cavities in the calibrated head 39 of the bracket 35 facilitates and guides adjustment. In a modified construction, Fig. 5, a two-way valve 60 replaces the sliding piston-valve. The upper side of piston 4 is continuously in communication with the supply pipe 59 by way of pipe 64. Depression of the handle 20a puts the port 3<a> in alignment with the delivery pipe 63; this position is maintained by the engagement of a lug 20b with the end of a lever 24<a>. Release occurs, and delivery ceases, when the falling arm 35 depresses rod 32<a> and trips the lever 24<a>. Refilling then occurs through the pipe 61. According to the Provisional Specification the chamber 1 may contain any desired minimum quantity of liquid, and means may be provided for control by the piston to cause the latter to operate repeatedly until the desired number of unit quantities has been delivered; further delivery is then automatically stopped.