GB519670A - Variable speed gearing for superchargers, fans, pumps and compressors of turbo and centrifugal types - Google Patents

Abstract

519,670. Hydraulic brakes. PARAVICINI, T. P. DE. May 31, 1938, No. 16209. [Class 103 (i)] [Also in Group XXIV] Variable-speed epicyclic gearing for driving turbo or centrifugal superchargers, compressors, pumps, or fans has one element, for instance a planet carrier, connected to the driving shaft, a second element, for instance an annulus, connected to the driven member, and a third or reaction member, for instance a sun gear, driving a liquid pump which comprises a fixed casing m, Fig. 5, containing a central gear k meshing with a number of secondary gears l to form a number of gear pump units, the highpressure region p of each unit communicating with the low-pressure region n of the adjacent unit through a passage q<1> provided with a control valve. Each gear l may mesh with one or more further gears so as to increase the number of pump units. Each control valve in the pump P includes a spring-loaded relief valve, so that the maximum speed of the driven member is limited to a predetermined value. As shown in Figs. 5, 6 and 8, each passage q<1> in the pump is controlled by a rotary sleeve valve q which also houses a spring-loaded relief valve t controlling a passage r leading from the associated high-pressure region p into the interior of the valve q, which latter is always open to the low-pressure region. The valves q are operated in unison by a ring B having slots engaging cranks u on the valves, the ring B being turned by a link c operated by a piston H in a cylinder E. The piston H is urged upwards by a spring G bearing against an adjustable abutment J and the two ends of the cylinder are connected to the mouth and throat of a Venturi tube F in the compressor and delivery pipe, whereby a constant delivery, depending on the setting of the abutment J, is obtained. The ends or one end only of the cylinder E may be connected to other selected parts in the circuit of the compressor &c. so as to obtain desired delivery characteristics. Cooled liquid is fed to the regions n by a pump, which may be the engine lubricating pump, through a pipe I with branches L, while liquid is discharged from one or more of these regions through a pipe O. Alternatively, liquid may be bled from the region p into a pipe leading through a cooler into a tank from which it returns by gravity to the regions n.