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 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.

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).

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 hydraulic excavator (1) includes a wireless authentication device (42) performing wireless authentication with a portable key device (41) and a vehicle body controller (39) allowing or prohibiting start of the engine (15) on the basis of authentication by the wireless authentication device (42) and an operation of a power switch (12). The wireless authentication device (42) transmits a request signal within an authenticable range and performs authentication when it receives an ID code for authentication replied from the portable key device (41) on the basis of the transmitted request signal. The vehicle body controller (39) allows start of the engine (15) by the power switch (12) when a gate lock lever (13) is switched to a lock position and the wireless authentication device (42) performs authentication by the portable key device (41).

A hydraulic excavator (1) includes a wireless authentication device (52) performing wireless authentication with a portable key device (51) and a vehicle body controller (48) for starting an engine (15) based on authentication by the wireless authentication device (52) and an operation of a start switch (12). The wireless authentication device (52) transmits a request signal within an authenticable range and performs authentication when it receives an ID code for authentication replied from the portable key device (51) based on the transmitted request signal. The vehicle body controller (48) prohibits driving of a hydraulic actuator (5E, 5F, 5G, 5H, 2E, 2F, 3A) when the portable key device (51) is outside of the authenticable range even if a gate lock lever (13) has been switched to an unlock position.

A hydraulic excavator (1) includes a wireless authentication device (52) performing wireless authentication with a portable key device (51) and a vehicle body controller (48) for starting an engine (15) based on authentication by the wireless authentication device (52) and an operation of a start switch (12). The wireless authentication device (52) transmits a request signal within an authenticable range and performs authentication when it receives an ID code for authentication replied from the portable key device (51) based on the transmitted request signal. The vehicle body controller (48) prohibits driving of a hydraulic actuator (5E, 5F, 5G, 5H, 2E, 2F, 3A) when the portable key device (51) is outside of the authenticable range even if a gate lock lever (13) has been switched to an unlock position.

Power machines, control systems and methods that adjust engine speed based upon actuation of user input controls that control other power machine functions such as travel functions and lift arm functions. By controlling engine speed at least partially in response to the user input devices controlling other machine functions, more optimal engine speeds can be achieved.

Power machines, control systems and methods that adjust engine speed based upon actuation of user input controls that control other power machine functions such as travel functions and lift arm functions. By controlling engine speed at least partially in response to the user input devices controlling other machine functions, more optimal engine speeds can be achieved.

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 a plurality of working chambers, a hydraulic circuit extending between a group of one or more working chambers of the hydraulic machine and one or more of the hydraulic actuators, each working chamber of the hydraulic machine comprising a low-pressure valve which regulates the flow of hydraulic fluid between the working chamber and a low-pressure manifold and a high-pressure valve which regulates the flow of hydraulic fluid between the working chamber and a high-pressure manifold. The hydraulic machine being configured to actively control at least the low-pressure valves of the group of one or more 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 one or more 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 one or more actuators.