| 摘要 |
<p>The impact hammer is driven by pressurised liquid and a double-acting cylinder. The piston rod is connected to the hammer body. The hammer is actuated by multiway valves and a signal system operated by piston rod movements. This hammer is controlled by the operator according to changing operating conditions. The operating pressure, however, is kept almost constant automatically. This ensures efficient utilisation of stored hydraulic fluid. The signal generator (14) for determining the upper position tends to shorten the working stroke length when the supply pressure falls. Conversely when supply pressure increases, so does working stroke length. The movable signal generator is connected to the regulating piston (13) of a double-acting regulating cylinder.</p> |
