A hydraulic energy regeneration system for a work machine for boosting a pressure of a return hydraulic fluid of a hydraulic cylinder and regenerating the hydraulic fluid, prevents a bottom pressure from reaching an overload relief set pressure and suppresses a changeover shock to ensure favorable operability.

The hydraulic energy regeneration system for the work machine, includes: a communication pressure boost passage that can boost a pressure of a discharge-side hydraulic fluid by communicating a discharge side and a suction side of the hydraulic cylinder with each other during an own weight fall of a driven body; a communication pressure boost valve that is disposed in the communication pressure boost passage and that can regulate one of or both of a pressure and a flow rate of the communication pressure boost passage; a reuse-side line and a reuse control valve or a regeneration-side line and a regeneration control valve that can regenerate a hydraulic fluid discharged from the hydraulic cylinder during the own weight fall of the driven body; and a controller. The controller is configured to reduce an opening degree of the communication pressure boost valve in response to an increase of the discharge-side pressure of the hydraulic cylinder right after the discharge-side pressure reaches a preset high load set pressure, and gradually reduces the opening degree of the communication pressure boost valve with passage of time.

At the time of starting up an engine (9) using an assist motor generator (10), a main controller (28) lowers a lower limit value in a charge/discharge range of an electricity storage device (19) from a first lower limit value (min1) to a second lower limit value (min2) through an energy management control part (28B). The main controller (28) heightens the lower limit value in the charge/discharge range of an electricity storage device (19) from the second lower limit value (min2) to the first lower limit value (min1) when the start of the engine (9) is completed. Further, the main controller (28) displays engine stop prohibition information on a display device (30) when the start of the engine (9) is completed and when an SOC of the electricity storage device (19) falls below the first lower limit value (min1).

A shovel is provided that includes a lower running body, an upper turning body pivotally mounted on the lower running body, an engine mounted on the upper turning body, a motor generator driven by the engine, a power storage device for storing electric power generated by the motor generator, an electric motor for supplying regenerative electric power to the power storage device, a selective reduction catalyst system for purifying exhaust gas by injecting a reducing agent stored in a reducing agent storage tank into an exhaust pipe of the engine, an abnormality detection unit for detecting an abnormality of the selective reduction catalyst system, and a control device that performs abnormality determination on the selective reduction catalyst system based on a detection result of the abnormality detection unit. The control device continues to control the electric motor before and after the abnormality determination.

To achieve saving of fuel consumption and noise reduction by adopting a hybrid type and miniaturizing an engine and to ensure safe and reliable battery charging in a case in which a charge amount of a battery is quite insufficient, a hydraulic work machine includes: a gate lock sensor (28); a forced charging switch (41); a work machine monitor (43) that notifies an operator that a charging rate of a battery (33) falls to be lower than a critical charging rate; and a machine controller (46). The machine controller (46) actuates a generator motor (31) as a generator to forcedly charge the battery (33) when a gate lock lever (26) is operated to a lock position (D), an engine control dial (12) designates a low idle engine speed, and the forced charging switch (41) is operated.

A pump that supplies hydraulic oil to a boom cylinder and a turning hydraulic motor; a regenerative hydraulic motor is coupled to the pump and to which the hydraulic oil discharged from the boom cylinder at a time of boom lowering and/or the hydraulic oil discharged from the turning hydraulic motor at a time of turning deceleration is/are led; an engine drives the pump; an alternator mounted to the engine and operable to rotate an output shaft of the engine when electric power is supplied to the alternator; an electrical storage device connected to the alternator; a power converter interposed between the alternator and the electrical storage device; and a controller that switches the power converter to either a servo-on state or a servo-off state and that controls the power converter either in a charging mode or in a discharging mode when switching the power converter to the servo-on state.

Provided is a hydraulic fluid energy recovery system for a work machine equipped with a hydraulic pump, a hydraulic actuator for driving the work machine, an operating device for operating the hydraulic actuator, and a regenerating device for recovering a return fluid flowing back from the hydraulic actuator. The hydraulic fluid energy recovery system includes: a fluid line for allowing the return fluid from the hydraulic actuator to flow through the line; a section for branching the fluid line into a plurality of fluid lines; a recovery circuit that serves as one of the branch fluid lines and includes the regenerating device; a discharge circuit that serves as the other of the branch fluid lines and discharges the return fluid to a tank; a flow control device disposed in the discharge circuit so as to be able to control a flow rate of the return fluid; an operation amount detector for detecting the operation amount on the operating device; and a control device configured to acquire the operation amount detected by the operation amount detector, calculate a target discharge flow rate of the return fluid flowing through the discharge circuit, and calculate a target regeneration flow rate of the return fluid flowing through the recovery circuit, the control device thereby controlling the flow control device according to the target discharge flow rate and also controlling the regenerating device according to the target regeneration flow rate.

Embodiments herein relate to a working machine that may include one or more batteries. The working machine may further include logic that is configured to: identify an operation plan to be performed by the working machine in a work area; identify an amount of power required to complete the operation plan; identify an amount of power remaining in the one or more batteries; alter, based on a comparison of the amount of power required to complete the operation plan to the amount of power remaining in the one or more batteries, the operation plan to generate a revised operation plan; and facilitate implementation, by the working machine, of the revised operation plan. Other embodiments may be described and/or claimed.

Provided is a work machine control method, a work machine control program, a work machine control system, and a work machine that allow an operator to easily grasp the state of a secondary battery. The work machine control method includes executing relevant control regarding at least one of charging and discharging of the secondary battery of the work machine in accordance with a temperature of the secondary battery; and displaying relevant control information (first information G41 and second information Im3) on the relevant control.

An intelligent work vehicle preheating system includes an electric drive subsystem containing a battery pack, a hydraulic subsystem containing a first hydraulic fluid (HF) heating device, and a first HF temperature sensor. A memory stores a first minimum target temperature at or above which a first hydraulic fluid body contained in the hydraulic subsystem is desirably maintained. A controller architecture selectively places the intelligent work vehicle preheating system in an off-duty preheat mode when a the electric drive subsystem is connected to an external power supply utilized to charge the battery pack. The controller architecture further controls the HF heating device to heat the first hydraulic fluid body when (i) the intelligent work vehicle preheating system is placed in the off-duty preheat mode, and (ii) the current temperature of the first hydraulic fluid body is less than the first minimum target temperature.

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.