| 摘要 |
1,116,452. Hydraulic apparatus. NATIONAL RESEARCH DEVELOPMENT CORPORATION. Oct. 26,1965 [Nov. 2, 1964], No. 44656/64. Heading F1P. Longitudinal waves of variable amplitude are transmitted through a duct 11, Fig. 1, charged with liquid by means of first and second pulse generators each comprising first and second stators 13,14 having groups of radial cylinders 15,16 opening into duct 11 and surrounded by a common driven rotor assembly 22 including cam tracks 25, 26 bearing against spherical pistons 19, 20; the second stator 14 being angularly adjustable relative to the first stator 13 whereby the generators operate in differing phases and the resultant amplitude in duct 11 may be adjusted between maximum and minimum values. Said angular adjustment of stator 14 is effected by a sleeve 30 driven through worm gears 28, 29 and splined to a tubular extension 31 of stator 14. The gear 28 carries a control lever 41, Fig. 3, which is rocked by a ram 50 biased by a spring 50a to the position of maximum pulse amplitude and opposed by hydraulic pressure in an output duct 42 when it opens a non- return valve 44 in a branch duct 45 connected by a duct 47 to the ram 50 and through a variable restriction 48 to a reservoir 46. Make-up liquid is withdrawn from reservoir 46 by a backing pump 53 which delivers past a non-return valve 52 when pressure in duct 42 falls below a predetermined value. |
