| 摘要 |
Electrically operated hammering machine comprising a drive piston 103 and a hammering piston 104 which forms part of the striking mechanism of the machine and is driven by the drive piston through the use of a compressed-gas cushion 106. A brushless alternating- current motor 101 drives the drive piston through the use of a crank mechanism 105. A semiconductor inverter 107 feeds power of variable amplitude and frequency to the motor 101. A handle-assigned starter 109,131 comprises a number of magnetically controlled changeover switches 144,145,146 which, for collaring-realization purposes, transmits a direct-current signal, which is variable from zero to maximum value, to a control unit 19,10 for the semiconductor inverter 107. In relation to this signal, the amplitude and frequency of electrical energy supplied to the motor 101 is controlled during collaring. <IMAGE> |
