A work machine includes an engine power management system. The work machine includes an engine, a hydraulic temperature sensor, and a coolant temperature sensor. The hydraulic temperature sensor is configured to monitor and transmit a hydraulic fluid temperature, and the coolant temperature sensor is configured to monitor and transmit a coolant fluid temperature. The work machine also includes an engine controller and a machine controller. The engine controller includes a processor, and is operatively associated with the engine and the coolant fluid temperature sensor. The machine controller includes a processor, and is operatively associated with the hydraulic fluid temperature sensor and the engine controller. The machine controller is configured to transmit a torque limit command to the engine controller when the hydraulic fluid temperature or the coolant fluid temperature exceeds a predetermined temperature threshold.

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.

A control device for a hydraulic machine such as a revolving excavator work machine in which a load-sensing pump control system is adopted The control device prevents variation in pump control characteristics among a plurality of hydraulic machines and also prevents variation in the operating speed of individual drive units in the hydraulic machines The control device; and it is configured to perform, by using a storage unit and a calculation unit outside the hydraulic machine, a process of causing an engine rotation state and a hydraulic actuator operation state to be specific states and calculating a correction rate for a control output value of an electromagnetic proportional valve for generating a control pressure, based on detection of an error in the flow rate of a hydraulic pump or its substitute numerical value such as the rotational speed and the like of a traveling motor which is easily detectable from outside.

The working machine includes a machine body, an engine provided on the machine body, 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 to selectively set either one of the assisting operation and the generating operation based on the acceleration of the machine body measured by the acceleration sensor.

A working machine having a base assembly including a ground engaging structure; an undercarriage connected to the ground engaging structure; a superstructure connected to the undercarriage; a working arm mounted to the superstructure; a connector connecting the undercarriage to the superstructure; and a drive arrangement located in the base assembly for moving the ground engaging structure to propel, in use, the working machine.

Provided is a construction machine configured so as to prevent wasteful fuel consumption by preventing an engine stall by means of the injection of an appropriate amount of fuel. A backhoe which is a construction machine in which a hydraulic pump is driven by power from an engine is configured so that the output torque characteristics of the engine is set on the basis of the atmospheric pressure detected by an atmospheric pressure sensor which is an atmospheric pressure detection means, and so that a rotational speed is set so that the maximum torque of the engine at a low idle rotational speed is greater than the maximum absorption torque of the hydraulic pump.

A carrier comprising at least one hydraulic cylinder having a piston, a controller and a piston position sensor, wherein the carrier is arranged to carry a tool through the use of the hydraulic cylinder and wherein the controller is configured to: receive control input for moving the tool; receive piston position information for at least one piston of the at least one cylinders; determine a current angle for the tool based on the piston position information; and determine that the current angle approximates a desired angle, and in response thereto halt the tool at the desired angle. According to an aspect the controller may be configured to detect and determine the position of a subject relative the carrier based on hydraulic pressure information and tool operational information. Further, the application concerns methods applied with the embodiments of said carrier.

A cost required to perform the diagnosis of the degradation such as a reduction in output power of an engine while engine degradation diagnosis accuracy is improved. To this end, a controller 37 (engine diagnosing device) determines whether a hydraulic pump 12 is in a preset loaded state (an operation scene where a load torque of the hydraulic pump 12 is in a stable state) for acquiring diagnosis data of an engine 10, and validates a controlled variable related to a torque command value Ta of speed sensing control as the diagnosis data of the engine 10 when it is determined that the hydraulic pump 12 is in the present loaded state, generates time history data using this validated controlled variable as a current feature variable, and enables this time history data to be displayed as trend data for engine diagnosis on a display device 38.

To increase frequency of use of auto idle, an engine is accelerated even more quickly than before and work involving a heavy load can be performed within a short period of time when an operator resumes work and recovers a speed of the engine. When an operation lever device is operated and the speed is low because of auto idle control, a pilot pump is unloaded to thereby reduce load torque on the engine. Operation of a compressor is also suspended while an air conditioner is operating. Furthermore, for a target speed of the engine, a speed at which work can be performed is set and the engine is accelerated. When the engine thereafter reaches a predetermined speed or a predetermined period of time thereafter elapses, the pilot pump is loaded and the operation of the compressor for the air conditioner is resumed.

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.