The working machine includes a traveling device, a traveling motor, a hydraulic pump including a swashplate, a prime mover to drive the hydraulic pump, a first servo-cylinder to set an angle of the swashplate, a charge pump to supply pilot fluid to the first servo-cylinder, a switching valve shiftable between a traveling position to supply the pilot fluid from the charge pump to the first servo-cylinder and a neutral position to stop the pilot fluid supply to the first servo-cylinder, a switching operation member operable to select either a traveling mode or a neutral mode, and a controller to shift the switching valve between the traveling position and the neutral position. The controller holds the switching valve at the neutral position after the switching operation member is operated to select the traveling mode until a rotation speed of the prime mover becomes not less than a first predetermined rotation speed.

A shovel enabled to set an engine revolution speed to revolution speeds including a revolution speed for a running operation and a revolution speed for an idling running operation that is lower than the revolution speed for the running operation includes an engine provided as a driving source of the shovel, an operating part configured to be driven by a driving force of the engine, an operation component configured to operate the operating part, a detecting device configured to detect a position of a movable portion of an operator and a position of the operation component, an operation determining part configured to determine a positional relationship between the movable portion and the operation component, and a control part configured to set the engine revolution speed of the engine based on the positional relationship between the movable portion and the operation component that is determined by the operation determining part.

A shovel enabled to set an engine revolution speed to revolution speeds including a revolution speed for a running operation and a revolution speed for an idling running operation that is lower than the revolution speed for the running operation includes an engine provided as a driving source of the shovel, an operating part configured to be driven by a driving force of the engine, an operation component configured to operate the operating part, a detecting device configured to detect a position of a movable portion of an operator and a position of the operation component, an operation determining part configured to determine a positional relationship between the movable portion and the operation component, and a control part configured to set the engine revolution speed of the engine based on the positional relationship between the movable portion and the operation component that is determined by the operation determining part.

A control device for an automatic transmission includes: a failure diagnosis section for diagnosing whether or not a failure has occurred in a shift control system of the automatic transmission; a fail-safe control section for fixing the automatic transmission into a predetermined gear position in response to confirmation of the failure of the shift control system of the automatic transmission; and an oil temperature rise regulation torque reduction control section for outputting a torque reduction request to suppress torque of a vehicle driving source, based on temperature of transmission operating oil of the automatic transmission, and outputting the torque reduction request in response to satisfaction of an oil temperature condition that is set lower in oil temperature when the automatic transmission is fixed in a first gear position by the fail-safe control section than when the automatic transmission is not fixed in the first gear position.

A construction machine management system in which a failure analysis or a failure-omen diagnosis of a machine body can be performed with a high degree accuracy and at a low cost is provided. In a machine body group of construction machines including at least one representative machine body having an engine control unit that detects a cumulative stress value of a diesel engine of the construction machine and a crankcase pressure sensor that detects a crankcase pressure, and at least one general machine body that has an engine control unit but does not have a crankcase pressure sensor, a center server performs a diagnosis of an omen of a failure state regarding the crankcase pressure of the general machine body based on correlation information between the cumulative stress value and the crankcase pressure obtained from the representative machine body and the cumulative stress value of the general machine body.

A shovel includes an attachment including a working assembly, a diesel engine provided with a supercharger, an oil hydraulic pump connected to the diesel engine provided with the supercharger, and a controller that executes a preload boost function, wherein the preload boost function is for increasing boost pressure of the supercharger prior to increasing a hydraulic pressure load on the oil hydraulic pump, wherein a range accessible by a predetermined part of the attachment includes a partial range at which, upon the working assembly being operated, the preload boost function is to be executed and a partial range at which, upon the working assembly being operated, the preload boost function is not to be executed.

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).

Provided is a hybrid work machine in which a hybrid system and a downsized engine are used. The hybrid work machine improves fuel consumption, improves exhaust characteristics, and reduces noise. The hybrid work machine also performs rapid charging of a power storage device while preventing decreases in the output power of a hydraulic pump if the charge amount of the power storage device is extremely insufficient. A vehicle body controller 46 performs engine revolution speed decreasing control in which, if the charge rate of a battery 33 becomes equal to or less than a minimum charge rate, the target revolution speed of an engine 11 is reduced. The vehicle body controller also performs torque reducing control in which the maximum absorption torque of a hydraulic pump 21 is reduced. By performing these control operations, the vehicle body controller coercively generates surplus torque for the engine and operates a generator-motor 31 as a generator with the use of the surplus torque, thereby rapidly charging the battery.

A balance assembly for an engine is provided. The balance assembly includes a first electric motor coupled to the engine and configured to rotate a first eccentric mass relative to the engine, the first eccentric mass being coupled to a first shaft of the first electric motor, and a second electric motor coupled to the engine and configured to rotate a second eccentric mass relative to the engine, the second eccentric mass being coupled to a second shaft of the second electric motor. The first and second electric motors are configured to rotate the first and second eccentric masses in order to balance a vibration characteristic of the engine.

A balance assembly for an engine is provided. The balance assembly includes a first electric motor coupled to the engine and configured to rotate a first eccentric mass relative to the engine, the first eccentric mass being coupled to a first shaft of the first electric motor, and a second electric motor coupled to the engine and configured to rotate a second eccentric mass relative to the engine, the second eccentric mass being coupled to a second shaft of the second electric motor. The first and second electric motors are configured to rotate the first and second eccentric masses in order to balance a vibration characteristic of the engine.