GB1435499A - Vibratory impact generators - Google Patents

Abstract

1435499 Vibrators INDUSTRY SECRETARY OF STATE FOR 10 Aug 1973 [23 June 1972] 29445/72 Heading F2X A vibratory impact generator comprises a vibrator block 10 provided on its underside with an impact face 12, at least one pair of outof-balance rotors 24, 26, and means for rotating each pair of rotors in a synchronized manner in opposite directions so that the net vibratory force produced lies in a pre-determined direction non-parallel to the impact face 12, the rotors 24, 26 being mounted in fluid pressure lubricatable bearings in the vibrator block 10 so that vibratory force is transmitted from the rotors to the block through a fluid film. In the embodiment shown, the vibrator block 10 is connected by restraining columns 14 with an impact member 16, the top ends of the columns 14 being located by a top plate 18, and when at rest is held mid-way between the impact member 16 and the top plate 18 by helical springs 70, 72 on each column 14. The vibrator block 10 is provided with two parallel bores 20, 22, each of which houses an out-of-balance rotor 24, 26. The rotors 24, 26 are driven by turbines 36, 38, both of which are supplied through a pipe 40 arranged to slide in a bearing 42 in the top plate 18. When the fluid supplied through pipe 40 has given up energy in the turbines 36, 38 it escapes through channels 44 along the axes of the rotors 24, 26 and out through a pipe 46 which can slide in a bearing 42 in the top plate 18. The rotors 24, 26 have a clearance of the order of 0À025 mm. with the bores 20, 22 and fluid under pressure is supplied to the clearance space through axially spaced rings of apertures (not shown). Thus the rotors 24, 26 are supported in hydrostatic bearings. The rotating outof-balance rotors 24, 26 are synchronized so that the vibrator block 10 vibrates in the direction of the columns 14 and this synchronism is maintained by two pulleys (64, 66) (Figs. 2 and 3, not shown) coaxial with the rotors and connected through a crossed belt 68. A suitable fluid for use with the generator is a solution of soluble oil in water. The impact member 16 may be provided with fixing holes or integral lugs which allow the attachment of, e.g. a chiselshaped tool for earth or rock cutting, or a cap member which can fit over the head of a pile which is required to be driven.