US 6,199,307 B1 · Battery-powered working machine

Abstract

It is intended to keep low the moment of inertia of a boom, etc. and maintain the whole of a working machine in good weight balance. At the same time, a highly efficient recovery of energy is to be attained to increase a continuous working time of a battery. A battery-powered working machine using a battery as a power source is provided. Rotation of a rotatable superstructure 12 and rising and falling motions of a boom 28 are performed directly by electric motors 22 and 34. The recovery of energy is attained by utilizing the electric motors 22 and 34. An arm 30 and a bucket 32 both located remote from a centroid position of the machine are actuated by an arm cylinder 38 and a bucket cylinder 40, which are hydraulic actuators less heavy than electric motors. Further, a hydraulic pump 18 for supplying those hydraulic actuators with a hydraulic oil is actuated by a hydraulic pump actuating electric motor 20 which utilizes the battery 14 as a power source.

Claims7

Dependent claims

A battery-powered working machine including a boom attached to a body of the working machine so as to be capable of rising and falling, a working portion attached to said boom, and a battery as a drive source, said battery-powered working machine comprising:

a boom actuating electric motor which is supplied with electric power from said battery and which actuates said boom directly;
a hydraulic pump;
a hydraulic pump actuating electric motor which is supplied with electric power from said battery and which actuates said hydraulic pump;
and
a hydraulic actuator which is supplied with hydraulic oil discharged from said hydraulic pump and which actuates said working portion attached to said boom.

2 more elements

A battery-powered working machine including a rotatable superstructure carried rotatably on a lower carriage, a boom attached to said rotatable superstructure so as to be capable of rising and falling, a working portion attached to said boom, and a battery as a drive source, said battery-powered working machine comprising:

a rotating electric motor which is supplied with electric power from said battery and which directly causes said rotatable superstructure to rotate;
a hydraulic pump;
a hydraulic pump actuating electric motor which is supplied with electric power from said battery and which actuates said hydraulic pump;
and
a hydraulic actuator which is supplied with hydraulic oil discharged from said hydraulic pump and which actuates said working portion attached to said boom.

2 more elements

A battery-powered working machine including a rotatable superstructure carried on a lower carriage rotatably, a boom attached to said rotatable superstructure so as to be capable of rising and falling, a working portion attached to said boom, and a battery as a drive source, said battery-powered working machine further including:

a boom actuating electric motor which is supplied with electric power from said battery and which actuates said boom directly;
a rotating electric motor which is supplied with electric power from said battery and which directly causes said rotatable superstructure to rotate;
a hydraulic pump;
a hydraulic pump actuating electric motor which is supplied with electric power from said battery and which actuates said hydraulic pump;
and
a hydraulic actuator which is supplied with hydraulic oil discharged from said hydraulic pump and which actuates said working portion attached to said boom.

3 more elements

Dependencies are inferred from the claim text.

Battery-powered working machine

Life of this patent

Battery-powered working machine

Life of this patent

Abstract

Claims7