GB1027802A - Method of tamping railway-track ballast and devices for implementing the method - Google Patents

Abstract

1,027,802. Railway track-packing machines. MATISA MATERIAL INDUSTRIEL S.A., and CONSTRUCTIONS MECANIQUES S.A., RENENS. Feb. 6, 1963 [Feb. 8, 1962], No. 4918/63. Heading E1G. In a method of tamping railway track ballast wherein at least one pair of co-operating tamping tools D, D<SP>1</SP> (Fig. 1) embedded in the ballast is moved from a spaced-apart starting position towards one another whilst vibrating them, the amplitude of the vibrations applied to the tools D, D<SP>1</SP>, as distinct from the frequency thereof is so modulated as to be less as the tools approach the end of their travel than at the start. Controlled modulation for the or each pair of tools D, D<SP>1</SP> is got by applying vibrations to the pivotal axis of a joint of the toggle bars AB, AB<SP>1</SP> along the bisecting axis (through A, A<SP>11</SP>) of the angle between them, so that when they are set at 80‹, the amplitude of the vibrations received at B, B<SP>1</SP> is virtually zero but increases as they are set at lesser angles, connecting the ends B, B<SP>1</SP> symmetrically to the respective tools D, D<SP>1</SP> of the or each associated pair and selectively adjusting the pivotal axis at A along the bisecting axis to vary the angle L at which the vibrations are applied thereat. A device V supplies vibrations at A and a jack X moves the joints and device V in bisecting the angle L and is on the mobile chassis of a ballast-tamping machine embodying the tools D, D<SP>1</SP> and the modulating mechanism. The jack X simultaneously moves the tools D, D<SP>1</SP> inwards, the toggle-bar ends B, B<SP>1</SP> transmitting vibrations and motive force to the tools. Another form shown utilises a common drive by having the jack between the levers BCD and B<SP>1</SP>C<SP>1</SP>D<SP>1</SP> and adjacent the line BB<SP>1</SP>, both previous forms being used with sleepers of a single width. A further form embodying a machine used with sleepers of more than one width has a device on the chassis to vary the distance between them and devices to adjust consequentially the lengths of the bars AB, AB<SP>1</SP>. Fig. 4 shows a form employing diserete independently operable jacks S and Q, the former acting on the levers BCE, B<SP>1</SP>CE<SP>1</SP> and the latter acting on the joint A along the bisecting axis. In a modification the roof used with sleepers of different width there are devices to adjust the lengths of the bars AC, AC<SP>1</SP> to vary the position of the points C and C<SP>1</SP>.