US 12,331,486 B2
Working machine
Daiki Tamba, Osaka (JP); Yukifumi Yamanaka, Osaka (JP); and Yuki Shimoike, Osaka (JP)
Assigned to KUBOTA CORPORATION, Osaka (JP)
Filed by KUBOTA CORPORATION, Osaka (JP)
Filed on Jun. 15, 2021, as Appl. No. 17/347,693.
Application 17/347,693 is a continuation of application No. PCT/JP2020/024730, filed on Jun. 24, 2020.
Claims priority of application No. 2019-122511 (JP), filed on Jun. 28, 2019; application No. 2019-122515 (JP), filed on Jun. 28, 2019; and application No. 2019-122516 (JP), filed on Jun. 28, 2019.
Prior Publication US 2021/0310214 A1, Oct. 7, 2021
Int. Cl. E02F 9/20 (2006.01); E02F 3/84 (2006.01)
CPC E02F 9/2075 (2013.01) [E02F 3/84 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A working machine comprising:
a machine body;
an engine provided on the machine body;
a sensor to detect a revolving speed of the engine;
a motor generator to be operated as a motor to assist driving of the engine in an assisting operation and to be operated as a generator by power of the engine to generate electricity in a generating operation;
a battery to store the electricity generated by the motor generator;
an acceleration sensor to measure acceleration of the machine body; and
a controller, including a processor and an inverter, configured or programmed to cause the inverter to operate the motor generator as the motor to perform the assisting operation and cause the inverter to operate the motor generator as the generator to perform the generating operation, wherein
the controller estimates what kind of traveling state the machine body is in based on the acceleration of the machine body measured by the acceleration sensor, and the controller is configured by electrical or electronic circuits or programmed to include a powering torque setting unit, a regenerating torque setting unit, and an operation control unit and to function so that:
the powering torque setting unit determines a value of a powering torque of the motor generator in the assisting operation based on the traveling state and the revolving speed of the engine;
the regenerating torque setting unit determines a value of a regenerating torque of the motor generator in the generating operation based on the traveling state and the revolving speed of the engine; and
the operation control unit causes the inverter to
operate the motor generator to perform the assisting operation at the value of the powering torque determined by the powering torque setting unit when the revolving speed of the engine is not higher than a first revolving speed, and
operate the motor generator to perform the generating operation at the value of the regenerating torque determined by the regenerating torque setting unit when the revolving speed of the engine is not lower than a second revolving speed that is higher than the first revolving speed.