| 摘要 |
<p>1,259,860. Tensioning endless tracks, etc. W. BRAUN. 3 July, 1969 [3 July, 1968], No. 33592/69. Heading F2G. A device for bringing together two free ends of a band or a track 5 comprises a tensioning unit to draw the two free ends together through the intermediary of a flexible pull member 36, e.g., a wire rope, running over tensioning pulleys 38 movable relatively to the unit to tension the rope, etc. The tensioning unit may be power or manually operated. As shown, the tensioning unit is manually operated and is secured to a plate 5 of an endless track by base plate and hooks 3. The tensioning unit comprises a ram with an outer cylinder 11 and an inner cylinder 12 acting as a piston. A spring 17 extends through the inner cylinder 12 and pulls it to its retracted position when the pressure in the outer cylinder 11 is released by operating a valve under the control of a knob 47. Pressure liquid from a vacuum-free reservoir constituted by a plastics bellows 20 is pumped into the outer cylinder 11 by means of a pump block 23 through non-return valves 27, 28 by operating a hand lever 30 which can be arrested by a catch 35. The axial movement of the inner cylinder 12 caused by pressure liquid moves the tensioning pulleys 38 away from the unit, and pulls the free end of the track through the wire rope 36 engaging eye hooks 39, 40, which are temporarily secured to the free end. The device can be used to assist in opening an endless track by relieving the pressure on a coupling pin which can be pulled out to disengage the free ends of the track.</p> |
