Systems and methods to activate one or more indicators, positioned on heavy hydraulic-based equipment to provide indication that the heavy hydraulic-based equipment is in an operation are described herein. The system may include a hydraulic initiation lever positioned proximate an operator's seat of the equipment and configured to be actuatable to an inactive position and an active position, the hydraulic initiation lever when in the active position configured to generate an unlock signal to thereby enable hydraulic operation of the heavy hydraulic-based equipment. The system may include one or more indicators configured to receive the unlock signal, the one or more indicators configured to activate in response to reception of the unlock signal and to deactivate in response to no reception of the unlock signal.

On detection of a difference between the operation amount detected by a first sensor and the operation amount received by a first communication unit from a slave, a master side controller executes at least one of stop control to automatically stop a construction machine and alarm control to cause a warning device to issue an alarm. On detection of a difference between the operation amount detected by a second sensor and the operation amount received by a communication unit from the master, a slave side controller executes at least one of the stop control to automatically stop the construction machine and the alarm control to cause the warning device to issue the alarm.

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 prime mover and hydraulic actuators, a hydraulic machine having a rotatable shaft engaged with the prime mover and having a plurality of working chambers, a hydraulic circuit extending between a group of working chambers of the hydraulic machine and the hydraulic actuators, each working chamber of the hydraulic machine having a low-pressure and a high-pressure valve regulating the flow of hydraulic fluid between the working chamber and a corresponding low-pressure manifold and a high-pressure manifold. The hydraulic machine controlling the low-pressure valves of the group of working chambers to select the net displacement of hydraulic fluid by each working chamber on each cycle of working chamber volume, and thereby the net displacement of hydraulic fluid by the group of working chambers, responsive to a demand signal, the apparatus further having a controller calculating the demand signal responsive to a measured property of the hydraulic circuit or an actuator.

A prime mover and a plurality of hydraulic actuators, a hydraulic machine having a rotatable shaft in driven engagement with the prime mover and comprising working chambers, a hydraulic circuit between working chambers of the hydraulic machine and the hydraulic actuators, each working chamber of the hydraulic machine comprising a low-pressure and high-pressure valves regulating the flow of hydraulic fluid between the working chamber and a corresponding low-pressure manifold and a high-pressure manifold. The hydraulic machine being configured to actively control the low-pressure valves of the working chambers to select the net displacement of hydraulic fluid by each working chamber on each cycle of working chamber volume, and thereby the net displacement of hydraulic fluid by the working chambers, responsive to a demand signal, wherein the apparatus further comprises a controller configured to calculate the demand signal in response to a measured property of the hydraulic circuit or actuators.

An energy recovery system for a machine having a movable work tool, a swing motor to swing the work tool about a vertical axis, a pump providing pressurized fluid to the swing motor, a power source outputting power to drive the pump, and a controller. The energy recovery system may include a first accumulator, a swing charge valve selectively connecting the swing motor to the first accumulator, an assist motor operatively connected to the power source, and a discharge selectively connecting the first accumulator to the assist motor. The swing charge valve may fluidly connect the swing motor to the first accumulator when fluid pressure from the swing motor is greater than a charge set pressure. The controller may cause the discharge valve to fluidly connect the first accumulator with the assist motor when the power demand on the power source is greater than a minimum assisted power demand.

An hydraulic system for a working machine, the system comprising an engine, and an engine speed sensor configured to detect the engine speed; a travel pump configured to actuate a travel actuator, and a travel pump pressure sensor configured to detect the travel pump pressure; a service pump configured to actuate a service actuator, and a service pump pressure sensor configured to detect the service pump pressure; and a micro-controller unit configured to receive input values from each sensor, and configured to determine whether each input value is within a predetermined range where the engine will not stall. The micro-controller unit is configured to provide an output when at least one input value is outside the predetermined range.

A control system for a work vehicle includes an acceleration detection device and a controller. The acceleration detection device detects an acceleration of the work vehicle. The controller determines whether the acceleration is greater than a first threshold and reduces the a vehicle speed when the acceleration continues to be equal to or greater than the first threshold over a predetermined first determination time period.

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.