Hitachi Construction Machinery Co., Ltd.

Hitachi Automotive Systems, Ltd.

Itaru Naya

Ken Takeuchi

Seiji Ishida

Shinya Imura

Masafumi Hita

Mutsumi Kikuchi

Hiroaki Amano

Shigeyuki Yoshihara

Akira Watanabe

Chiaki Takahashi

Shinichiro Yoshida

A management server receives a maximum value and a minimum value of the respective voltages in a plurality of battery cells configuring an electricity storage device of a hydraulic excavator from the hydraulic excavator, and stores the values in a storage device. Discharge characteristics of the electricity storage device are stored in the storage device in the management server. A battery state estimation calculating unit in the management server calculates an estimation maximum value and an estimation minimum value of cell voltages in the present or in the future by adding the discharge characteristics stored in the storage device to the latest maximum value and the latest minimum value of the cell voltages stored in the storage device. A management information producing unit outputs information based upon the estimation maximum value and the estimation minimum value of the cell voltages calculated in the battery state estimation calculating unit.

Electricity storage device management computer for a construction machine

A relay () connects and disconnects an electrical circuit to which an inverter () and an electricity storage device () are connected. A BCU () controls the electricity storage device (). An HC () controls an electric motor (), the inverter () and the BCU (). The HC () and the BCU () respectively have FET switches () for controlling supply and stop of the excitation current in the relay (). When the electricity storage device () is determined to be in an abnormal state, the BCU () transmits an abnormal signal to the HC (), and when a predetermined time has elapsed, turns off (opens) the first FET switch () of the BCU (). The HC () executes stop processing based upon the abnormal signal received from the BCU () and then turns off (opens) the second FET switch () of the HC ().

Electricity storage device controller, electric system and construction machine

A main controller and a hybrid controller control an engine, an assist generator motor, a hydraulic pump and an electricity storage device. In this case, the hybrid controller is provided with a performance state recovery part that performs performance state recovery of the electricity storage device. In a case where a performance state amount varying with repetition of a discharge and a charge of the electricity storage device, specifically, a current integrated value ratio of the electricity storage device goes beyond a predetermined threshold value (L1%), the performance state recovery part limits power of the hydraulic pump. Thereby, the performance state recovery part performs the performance state recovery of the electricity storage device.

Construction machine

A hybrid work machine includes a controller and a temperature sensor that detects an electric storage device temperature. In a case where (Tp+Tc)&#x2265;Te_min, the controller carries out a first comparison in which the controller compares a value of [(Tp+Tc)&#x2212;Te_min] with a value of Ta_SOC, and the controller then selects a lower value of the first comparison. The controller then carries out a second comparison in which the controller compares the selected lower value of the first comparison with a value of [(Tp+Tc)&#x2212;Te_max)]. The controller then sets a higher value of the second comparison as the torque of the assist motor Ta, wherein Tc is an accessory torque, Ta_SOC is an adjustment assist motor torque based on a current state of charge of the electric storage device, Ta is the torque of the assist motor, and Te_max is an engine maximum torque.

Hybrid work machine

An electric power storage device () disposed on a revolving frame () located closer to an upstream side in a flow direction of cooling air (F) than a heat exchanger () is provided on an upper revolving structure (). The electric power storage device () has a box-shaped casing () forming an outer wall and a battery module () provided in the casing () and accommodating an electrolyte. An electrolyte discharge pipe () for discharging an electrolyte mist and/or electrolyte injected out of the battery module () at abnormality of the battery module () to an outside of the upper revolving structure () is provided on the casing ().

Growing community of inventors

Tsuchiura, Japan

Itaru Naya