Patent GB-104389-A (GB)
Title: Improvements in and relating to Hydraulic Power Transmitters.
Inventor: FORD EUGENE AMZI
IPC: F16H39/06
Filed: 1916-03-03
Abstract: 104,389. Ford, E. A. March 3, 1916. Fixed - abutment t y p e ; balancing moving parts; regulating pumps and motors; reversing.-Relates to hydraulic transmission gear of the type in which a pump consisting of a rotary member with radially sliding vanes and having a variable and reversible delivery is connected with one or more hydraulic motors of the same general type. Fig. 1 represents in sectional plan the application of the apparatus to a motor-vehicle. The driving-shaft 2 of the engine is connected by an Oldham coupling 8 to the rotary pump body 6, Figs. 1 and 3. A thrust bearing 2<a> and thrustrod 4 are provided as shown in Fig. 2, which is a sectional elevation of the gear. Radial slots 9 in the rotary piston carry blades 10, which are normally held outwards by centrifugal force. A liquiddistributing sleeve 12 surrounds the piston 6, and is provided with ports 19. The sleeve is spring-tempered and provided with lugs 15, 15 bearing against cams 16, 16, so that it may be distorted from its naturally oval shape with long axis in the line 15-15 to a circular shape or to an oval shape with its long axis at right-angles to the line 15-15. The lugs 15 and spring-pressed packing-members 17, 17 ensure liquid-tightness at four points of the circumference. Each cam carries a pinion which gears with the toothed ring 21 which is operated by the pinion 28 on the spindle 27. The two opposed passages 25 act as suction conduits and the two passages 26 as delivery conduits so that the piston is balanced against side thrust. The delivery of the pump may be varied from a maximum through zero to a reverse maximum by turning the cams 16 to change the shape of the sleeve 12. The driven motors are mounted on the shafts 35 by means of Oldham couplings, end thrust being taken by flanges and by the thrust-rod 36. The motor casing is composed of a cylinder 40, two end plates 41 and an intermediate plate 42. The cylinder 40 has an elliptical bore and is provided with two opposite ports 44 communicating with passages 50 in the casing. Two other passages 51 are also provided, the four passages acting as supply and delivery ports in similar manner to those of the pump. When the pressure of the liquid delivered by the pump is abnormal, a by-pass valve is operated so as to return the liquid to the suction side of the pump. A valve-rod 60 carries two piston valves 61, 62, Fig. 2, and also a grooved nut 66 engaging with the lever 67 controlled by the spring 68, which keeps the valves closed against any desired pressure. The areas of the valve faces and the valve-rods are so arranged that the valves open whatever may be the direction of the delivery of the pump. The bypass valves may be operated manually by the rod 70 acting against the inclined face 69 of the lever 67. To remove air from the system a float valve 76 is provided, together with a ball valve 79. Reservoir spaces 80, 81, 82 are provided for a reserve supply of liquid which is admitted to the system by a valve 83. The liquid-controlling sleeve 12 may be modified as shown at 12<a>, Fig. 8, the outer surface being cylindrical and the inner elliptical. The variation in delivery is secured by rotating the sleeve. In an alternative form, the delivery of the pump may be fixed and the capacity of the motors variable.