A shovel according to embodiments of the present invention includes a lower travelling body, an upper swivel body, an operation attachment, an engine, a motor generator which is connected to the engine, a hydraulic pump which is connected to the motor generator and supplies hydraulic oil to the operation attachment, a swiveling electric motor which is mounted on the upper swivel body, a power storage device, a DC bus which electrically connects the power storage device and the swiveling electric motor to each other, and a control device, in which the control device decreases a charging/discharging limit value of the power storage device and changes a discharging requirement value which is the maximum value of power which is supplied from the power storage device to the swiveling electric motor, according to a decrease of temperature.

A hybrid or battery type working machine including a hydraulic pump, an electric motor, an electric storage device, and a control device which controls a pump absorption horsepower maximum value in accordance with an amount of electricity stored in the electric storage device. The control device reduces the pump absorption horsepower maximum value by dividing the pump absorption horsepower maximum value into a plurality of regions having different target flow rates, and reduces the pump absorption horsepower maximum value from an old pump absorption horsepower maximum value corresponding to the pump absorption horsepower maximum value which has not yet been reduced to a new pump absorption horsepower maximum value corresponding to the pump absorption horsepower maximum value which has been reduced, so that temporal differences among the regions can increase in a descending order of a target flow rate.

A control device of construction machine that performs tasks by driving a hydraulic pump by means of an electric motor that is driven by electric power of a battery device that is capable to charge and discharge and an engine that is mechanically coupled to the electric motor, includes: a charging/discharging control unit that controls the charging/discharging of the battery device in such a manner that, in case that a heavy load task where an output of the hydraulic pump is large and a light load task where the output of the hydraulic pump is small are alternately performed, when the output of the hydraulic pump during the heavy load task is increased or a time proportion of the heavy load task in the unit period is increased, an average value of charging current of the battery device per the unit period increases, and when the output of the hydraulic pump during the heavy load task is further increased or the time proportion of the heavy load task in the unit period is further increased, then the average value of the charging current of the battery device per the unit period decreases.

A controller sets a target flow rate of a regenerative hydraulic motor at zero or a low flow rate within an extent in which hydraulic pressure in a regeneration hydraulic line does not become negative pressure when a detected pressure PS detected by a pressure sensor is lower than a first set value previously set by overload relief valves, sets the target flow rate of the regenerative hydraulic motor at a value corresponding to the detected pressure when the detected pressure is higher than or equal to the first set value, and controls the revolution speed of a generator/motor in such a manner that a flow rate through the regenerative hydraulic motor equals the target flow rate. With such features, excellent operability equivalent to that in the conventional technology can be secured.

A hybrid work machine has an engine, an assist motor, a hydraulic pump which is driven by the total torque of the engine and the assist motor, and an electric storage device which accumulates electric power generated by the assist motor and supplies the electric power when the assist motor performs electric discharge. The continuous electric discharge from the electric storage device due to continuous operation at high load pressure can be suppressed without an operator experiencing an unusual operational characteristic. To this end, a pump flow rate correction control unit judges whether each hydraulic pump is in a high load operation state or not based on the output horsepower and/or the delivery pressure of each hydraulic pump and performs control such that the delivery flow rate gradually decreases when the hydraulic pump is in the high load operation state and this state continues beyond a predetermined time.

Systems and methods are disclosed for managing task assignments for a plurality of work machines at a site. An assignment engine may: receive first state data for a work machine including historical data, operating condition, and location data, and second state data for the site including characteristic data for materials and a plurality of available tasks; predict performance data and energy consumption data of the work machine for a task; select a task for the work machine by inputting first state data and second state data into a trained reinforcement-learning model, wherein: the model has been trained to learn an assignment policy that optimizes a reward function such that the learned policy selects a task for at least one work machine from the plurality of tasks available at the site; and cause the at least one work machine to be operated according to the at least one task assignment.

A shovel includes a lower traveling body; an upper swivel body that is mounted on the lower traveling body; an electric motor for swiveling that drives the upper swivel body in a swiveling manner; a mechanical brake that holds a swiveling stopped state of the upper swivel body; an engine; a hydraulic pump that discharges hydraulic oil with the power of the engine; a hydraulic actuator that is driven by the hydraulic oil discharged by the hydraulic pump; a pressure detecting unit that detects the discharge pressure of the hydraulic pump; and a control device that controls the mechanical brake on the basis of information on the discharge pressure detected by the pressure detecting unit.

A work machine is provided. The work machine may include a power module configured to provide power including a battery and an engine coupled to a folding heat exchange device. The work machine may also include a drive module configured over a track roller frame with one or more motors. The work machine may also include a hydraulic module including one or more devices in a front region and one or more devices in a rear region to cut or rip encountered material.

An electric drive machine includes a power module configured to provide power including a battery and an engine coupled to a folding heat exchange device. The electric drive machine may also include a drive module configured with one or more motors and positioned over a track roller frame. The electric drive machine may also include a ripping module configured with one or more ripping devices to rip encountered material. The electric drive machine may also include a hydraulic module with one or more devices in a region to cut or rip the encountered material.

A control system of a hybrid construction machine includes a regeneration passage switching valve having a normal position where flow of working fluid is blocked, and a regeneration position allowing for the working fluid to flow from main passages to a regeneration motor when a working fluid pressure of the main passages reaches a set pressure during operation of the actuators, and an assist switching valve having a normal position proportionally dividing the working fluid of an assist passage into a regeneration passages, a first switching position supplying more working fluid of the assist passage to one of the main passages when that the one has a higher working fluid pressure, and a second switching position supplying more working fluid of the assist passage to the other one of the main passages when that the other one has a higher working fluid pressure.