Device capable of quickly increasing rotating speed of engine

Abstract

The invention provides a device capable of quickly increasing the rotating speed of an engine. The device comprises the engine provided with a booster, a variable-capacity hydraulic pump driven by the engine, a hydraulic brake driven by working oil sprayed out from the hydraulic pump, a boosting pressure detector for detecting the boosting pressure of the booster and a controller used for controlling the absorption torque, namely the pump torque of the hydraulic pump. During the period that the rotating speed of the engine reaches a target rotating speed from a rotating speed lower than the target rotating speed, the controller is used for solving the target pump torque through a preset relation between the no-load rotating speed of the engine and the target pump torque and correcting the target pump torque to limit the actual pump torque as the corrected target pump torque on the basis of boosting pressure detected by the boosting pressure detector in the mode that the lower the boosting pressure is, the smaller the target pump torque gets.

Description

technical field [0001] The invention relates to a device that can rapidly increase the engine speed, belonging to the technical field of machinery. Background technique [0002] The rotation speed of the engine mounted on the excavator at the time of no load is usually determined by the operation of the engine rotation speed setter called an acceleration potentiometer, and the selection of the work mode (if there are multiple determinants, a lower value is selected ) and so on to decide. The excavator uses the determined rotational speed as a target engine rotational speed, and controls the fuel injection amount in the engine. On the other hand, an excavator equipped with an auto-deceleration function performs deceleration by reducing the engine speed to the set speed when a preset deceleration condition (for example, a state without lever operation continues for a specified time) is satisfied. The automatic deceleration control of the rotational speed is performed, and wh...

AI Technical Summary

Problems solved by technology

However, the countermeasure of suppressing the pump torque to the minimum in this way leads to the problem that the brake operation, that is, the excavator operation cannot be substantially performed until the engine speed is completely increased.

This problem is not limited to deceleration and reset, but may also occur when the engine is raised from a low speed to the target speed, including when the engine is started.

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