GB936153A - Improvements relating to hydraulic transmission of power - Google Patents

Abstract

936,153. Hydraulic apparatus. J. C. BAMFORD (EXCAVATORS) Ltd. Sept. 7, 1961 [June 9, 19601, No. 20234/60. Class 69 (2). Apparatus for the hydraulic transmission of power comprises a motor 13 for driving means for reciprocating the plunger of a transmitter 11 which imparts pulses to a column of fluid 18 between the transmitter and a receiver 15 for operating a percussion tool 17, such as a road drill, hammer, tamper or riveter, the natural period of vibration of the column being in resonance with the period of the impulses given by the transmitter, a clutch 14 between the motor and the means for reciprocating the plunger, and a control lever 19 or the like on, or in association with, the tool for controlling the operation of the clutch. The control lever may be connected hydraulically, electrically or by a flexible cable 21, which may be clipped to the pipe 18 containing the column of fluid or pass through the pipe, to a bell-crank lever 22 controlling the clutch 14 between the motor 13 and means, such as a cam on a shaft 12, for reciprocating the plunger. The transmitter may have a plurality of plungers each connected to a separate receiver. The plungers may be reciprocated by a common cam or separate cams; in the latter case, a separate clutch may be provided for each cam to enable the tools to be operated independently. Specification 934,942 is referred to.