Hybrid Construction Machinery

Abstract

To provide a hybrid type construction machine which has rotational operation operability without discomfort compared with conventional construction machines, and which can control the storage amount of the power storage device without increasing the capacity of the power storage device. Within an appropriate range considering the service life. It has: an electric motor and a hydraulic motor for driving the rotating body; an electric storage device; and a controller for controlling the charge and discharge of the electric storage device, and the controller has: a storage unit that stores information related to the storage amount of the electric storage device and according to the electric storage capacity of the rotating body. a discharge command area set according to the rotational speed; and a calculation unit for adjusting the power of the electric motor according to the storage capacity of the power storage device when the storage capacity of the power storage device reaches the discharge command range stored in the storage unit. The additional drive torque command value of the electric motor whose operating amount is increased is calculated, and the additional drive torque command value is output to the electric motor side to drive the rotating body.

Description

technical field [0001] The present invention relates to a hybrid construction machine having a revolving body such as a hydraulic excavator, and more particularly to a hybrid construction machine having a revolving body including an electric motor for driving the revolving body and an electric storage device. Background technique [0002] In the past, the mainstream of construction machines with rotating bodies such as hydraulic excavators was to drive the hydraulic pump with the engine, and the hydraulic motor was rotated by the hydraulic pressure discharged from the hydraulic pump to drive the rotating body, which is an inertial body. However, in recent years, In order to improve the fuel efficiency of the engine, reduce the noise level, and reduce the amount of exhaust gas, etc., a hybrid system is proposed to drive the rotating body using both the electric motor and the hydraulic motor that are driven by receiving electric energy from the power storage device. machine (f...

AI Technical Summary

Problems solved by technology

[0010] In addition, if there is a large-capacity power storage device, although the above-mentioned energy management can be unnecessary, there is a disadvantage that as the capacity of the power storage device increases, the installation space of the power storage device in the construction machine increases, And the cost of construction machinery becomes high

[0011] In addition, even if energy management is implemented so that the storage capacity of the power storage device is within an appropriate range of use in consideration of the service life, since the mechanical operation mode is not specified, the energy consumed by the electric motor during acceleration driving The difference between the electric energy and the electric energy generated by the electric motor during deceleration driving, and the storage capacity of the electric storage device may exceed the appropriate range

In order to prevent this situation, it is considered to increase the capacity of the power storage device, but as mentioned above, it is not desirable to increase the capacity of the power storage device from the viewpoint of installation space and cost.

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