Drive control system of operating machine, operating machine including drive control system, and drive control method of operating machine

Patent metadata

Field	Value
Publication number	US-10435866-B2
Application number	US-201515541460-A
Country	US
Kind code	B2
Filing date	Dec 24, 2015
Priority date	Jan 6, 2015
Publication date	Oct 8, 2019
Grant date	Oct 8, 2019

Abstract

A drive control system includes an electric motor, a capacitor, a revolution sensor, a driving device, and a control device. The driving device causes the capacitor to supply electric power to the electric motor to operate the electric motor and causes the capacitor to store the electric power, generated by the electric motor, to brake a turning body. The driving device configured as above is driven by driving electric power supplied from the capacitor. When a charging stop condition is satisfied, the control device stops the driving electric power supplied from the capacitor to the driving device. The charging stop condition is a condition that a turning speed detected by the revolution sensor is a predetermined speed or less while the turning body is decelerating.

First claim

The invention claimed is:

1. A drive control system of an operating machine,
the drive control system comprising:
an electric motor configured to receive supply of electric power to turn a turning body of the operating machine and configured to generate the electric power to brake the turning body;
a power storage device configured to charge and discharge the electric power;
a driving device driven by driving electric power supplied from the power storage device, configured to cause the power storage device to supply the electric power to the electric motor to operate the electric motor, and configured to cause the power storage device to store the electric power, generated by the electric motor, to brake the turning body;
a speed detector configured to detect a turning speed of the turning body; and
a control device configured to stop the supply of the driving electric power from the power storage device to the driving device when the turning body decelerates, and a charging stop condition is satisfied, the charging stop condition being where the turning speed detected by the speed detector is a predetermined speed or less, and the predetermined speed is a value greater than zero.

2. The drive control system according to claim 1 , wherein the predetermined speed is a speed immediately before an electric power state of the power storage device changes from charging to discharging.

3. The drive control system according to claim 1 , wherein the predetermined speed is a speed at which steady loss energy consumed by the electric motor and the driving device when braking the turning body becomes larger than charging electric power generated by the electric motor.

4. The drive control system according to claim 1 , further comprising:
a liquid pressure motor configured to receive supply of a pressure liquid to turn the turning body in cooperation with the electric motor; and
a liquid pressure supply device configured to supply the pressure liquid to the liquid pressure motor, wherein:
the liquid pressure motor brakes the turning body in such a manner that discharge pressure discharged from the liquid pressure motor is made higher than supply pressure supplied to the liquid pressure motor;
the liquid pressure supply device adjusts the discharge pressure of the liquid pressure motor; and
when the charging stop condition is satisfied, the control device controls an operation of the liquid pressure supply device to increase the discharge pressure of the liquid pressure motor.

5. The drive control system according to claim 4 , further comprising a rotation braking unit configured to brake rotation of an output shaft shared by the liquid pressure motor and the electric motor, wherein
when the charging stop condition is satisfied, the control device controls an operation of the rotation braking unit to brake the rotation of the output shaft.

6. The drive control system according to claim 4 , further comprising an input device to which an adjustment value regarding the turning speed of the turning body is input, wherein:
the control device controls operations of the driving device and the liquid pressure supply device such that the turning speed of the turning body becomes a turning speed corresponding to the adjustment value output from the input device; and
the charging stop condition includes a condition that the adjustment value output from the input device is a predetermined value or less.

7. A drive control system of an operating machine,
the drive control system comprising:
a liquid pressure motor configured to receive supply of a pressure liquid to turn a turning body;
a liquid pressure supply device configured to supply the pressure liquid to the liquid pressure motor;
an electric motor configured to receive supply of electric power to turn the turning body in cooperation with the liquid pressure motor and configured to generate the electric power to brake the turning body;
a power storage device configured to charge and discharge the electric power;
a driving device driven by driving electric power supplied from the power storage device, configured to cause the power storage device to supply the electric power to the electric motor to operate the electric motor, and configured to cause the power storage device to store the electric power, generated by the electric motor, to brake the turning body;
a speed detector configured to detect a turning speed of the turning body; and
a control device configured to stop the supply of the driving electric power from the power storage device to the driving device when the turning body accelerates or turns at a constant speed, and an assist stop condition is satisfied, the assist stop condition including a condition that an amount of electric power stored in the power storage device is a predetermined value or less.

8. An operating machine comprising:
the drive control system according to claim 1 ; and
the turning body, wherein
the electric motor turns the turning body via a reducer.

9. A drive control method of a drive control system of an operating machine,
the drive control method comprising:
a speed detecting step of detecting a turning speed of a turning body of the operating machine, the turning body being turned by an electric motor driven by electric power supplied from a power storage device;
a determining step of determining whether or not a charging stop condition is satisfied when the turning body is decelerated in such a manner that the driving device stores the electric power, generated by the electric motor, in the power storage device to brake the turning body, the charging stop condition being where the turning speed detected in the speed detecting step is a predetermined speed or less, and the predetermined speed is a value greater than zero, or a determining step of determining whether or not an assist stop condition is satisfied when the turning body accelerates or turns at a constant speed, the assist stop condition including a condition that an amount of electric power stored in the power storage device is a predetermined value or less; and
a stopping step of stopping the supply of the electric power from the power storage device to the driving device when it is determined in the determining step that the charging stop condition or the assist stop condition is satisfied.

Assignees

• Kawasaki Heavy Ind Ltd

Inventors

• Yudate yoji
• Iwabe Kazuya
• Muraoka Hideyasu

Classifications

• E02F9/2091

  Control of energy storage means for electrical energy, e.g. battery or capacitors (energy recovery arrangements in hydraulic or pneumatic drives E02F9/2217) · CPC title

• F15B2015/206

  Combined actuation, e.g. electric and fluid actuated · CPC title

• E02F9/2217 Primary

  with energy recovery arrangements, e.g. using accumulators, flywheels · CPC title

• B66C23/84

  Slewing gear (anti-friction bearings F16C) · CPC title

• E02F9/123 Primary

  Drives or control devices specially adapted therefor (E02F9/125 and E02F9/128 take precedence) · CPC title