To provide a motor-driven construction machine capable of preventing an overload current of a relay coil at an ON operation of a key switch even when a battery is consumed due to discharging, and reliably starting a low voltage power supply circuit.SOLUTION: A first battery selection switch 23 is switched to a battery A side and a relay coil 26 is excited with electric power from the battery A in response to an ON operation of a key switch 25 to close a power supply switch 19. The voltage is lowered by supplying electric power from a high voltage power source 18 to a low voltage power source 20 via the power supply switch 19, and the electric power after the lowering of the voltage is used for charging of the battery A or driving of a motor 22 in accordance with the switching of operation state switching switches 21, 24. At the time of opening of the power supply switch 19, the power of the battery A is supplied to the motor 22 to drive it by switching of the operation state switching switches 21, 24. When a voltage of the battery A is less than a first determination value, a first battery selection switch 23 is switched to a battery B side by a battery switching control unit 31.SELECTED DRAWING: Figure 2
【課題】放電によりバッテリが消耗した場合でも、キースイッチのON操作時のリレーコイルの過電流を未然に防止でき、確実に低圧電源回路を起動できる電動式建設機械を提供する。【解決手段】第1バッテリ選択スイッチ23をバッテリA側に切り換え、キースイッチ25のON操作に応じてバッテリAからの電力によりリレーコイル26を励磁して電源スイッチ19を閉成する。電源スイッチ19を介して高圧電源18からの電力を低圧電源20に供給して降圧し、降圧後の電力を作動状態切換スイッチ21,24の切換に応じてバッテリAの充電またはモータ22の駆動に利用する。また、電源スイッチ19の開成時には、作動状態切換スイッチ21,24の切換によりバッテリAの電力をモータ22に供給して駆動する。バッテリAの電圧が第1判定値未満になると、バッテリ切換制御部31により第1バッテリ選択スイッチ23をバッテリB側に切り換える。【選択図】図2
MOTOR-DRIVEN CONSTRUCTION MACHINE
電動式建設機械
2021-03-11
Patent
Electronic Resource
Japanese
IPC: | H02J CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER , Schaltungsanordnungen oder Systeme für die Abgabe oder Verteilung elektrischer Leistung / B60R Fahrzeuge, Fahrzeugausstattung oder Fahrzeugteile, soweit nicht anderweitig vorgesehen , VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR |
European Patent Office | 2023
|Engineering Index Backfile | 1903
Engineering Index Backfile | 1904