{
  "$type": "site.standard.document",
  "description": "An electromotive drive device for a construction machine, which is capable of lengthening its operating time, is provided. The electromotive drive device of an electric motor-driven mini-excavator includes an electric power storage device 7, a motor-generator 27 which performs the transfer of power…",
  "path": "/patents/978040",
  "publishedAt": "2014-02-26T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "B60L15/2009",
    "HITACHI CONSTRUCTION MACHINERY [JP]"
  ],
  "textContent": "An electromotive drive device for a construction machine, which is capable of lengthening its operating time, is provided. The electromotive drive device of an electric motor-driven mini-excavator includes an electric power storage device 7, a motor-generator 27 which performs the transfer of power to and from the electric power storage device 7, a hydraulic pump 29 driven by the motor-generator 27, a plurality of directional control valves 32, 34 which respectively control the flow of pressurized fluid from the hydraulic pump 29 to a plurality of hydraulic actuators 13A, 19, and a plurality of operating devices 31, 33 which respectively operate the plurality of directional control valves 32, 34. The electromotive drive device is provided with a bidirectional converter 28 which decelerates the motor-generator 27 to an idle revolution speed when X seconds have elapsed in a state in which the plurality of directional control valves 32, 34 are all not operated. The bidirectional converter 28 performs regenerative control to convert an inertial force of a rotor of the motor-generator 27 to power and charge the electric power storage device 7 when it decelerates the motor-generator 27 from a standard revolution speed to the idle revolution speed.",
  "title": "ELECTROMOTIVE DRIVE DEVICE OF CONSTRUCTION MACHINE"
}