Samsung Heavy Industries Co., Ltd.

Volvo Construction Equipment Korea Co., Ltd.

Myung Hoon Song

Jeong Yong Seo

In Taek Nam

Si Cheon Lee

Geon Hwang

Disclosed is an apparatus for increasing the operating capability of a construction machine during a fine operation mode and a method for the same. The apparatus being capable of preventing a merged hydraulic fluid from being supplied into a hydraulic actuator and increasing the pressure of the hydraulic fluid being supplied into the hydraulic actuator during the fine operation mode. The apparatus includes a detector that detects the RPM count of the engine of the construction machine and determines whether the engine is switched into the fine operation mode. A first anti-confluence valve and a second anti-confluence valve prevent a first hydraulic fluid supplied into the first actuator and a second hydraulic fluid supplied into the second actuator from merging while either the first actuator or the second actuator is operating. An anti-confluence relay turns the first anti-confluence valve and the second anti-confluence valve on/off. Finally, a controller turns the anti-confluence relay on/off in accordance with a signal generated by the detector.

Apparatus for improving the operating capability of a construction

A method for controlling the operation of a power excavator during a land finishing work is disclosed. In the above method, the bucket, arm and swing unit are controlled in response to output signals from a handling signal input means. Meanwhile, the boom is controlled as follows. That is, when a boom handling signal is output from the handling signal input means, the boom is controlled in response to the boom handling signal. However, when the handling signal input means does not output a boom handling signal, the boom is controlled by a geometrical operation of signals output from the boom, arm and bucket sensors and a land finishing angle for calculating reference boom angle data. The reference boom angle data is control-operated to output an automatic boom control signal, thus controlling the boom in order to move the bucket tip on a land with the land finishing angle in response to an arm handling signal output from the handling signal input means.

Method for controlling the operation of power excavator

A method for controlling the RPM of an engine in a hydraulic construction machine. A reference throttle lever position value and a reference engine RPM value are set to allow the engine to have a target output characteristic. A first control arithmetic operation is performed in response to a present throttle lever position value and the set reference throttle lever position value to allow a difference between the present throttle lever position value and the set reference throttle lever position value to be within the range of a mechanical error of an engine throttle control mechanism. A first control signal is generated as a result of the first control arithmetic operation to control the RPM of the engine. Then, a second control arithmetic operation is performed in response to a present engine RPM value and the set reference engine RPM value to allow the present engine RPM value to be approximated to the set reference engine RPM value under the condition that a difference therebetween is within the range of the mechanical error of the engine throttle control mechanism. A second control signal is generated as a result of the second control arithmetic operation to control the RPM of the engine.

Method for controlling RPM of engine in hydraulic construction machine

An apparatus for and a method of controlling the engine RPM in hydraulic construction equipment, being capable of detecting a neutral valve position corresponding to the idle state of the construction equipment and controlling the engine to drive at a low RPM while the construction equipment is in its idle state, thereby achieving a reduced noise generation and reduced fuel consumption. The apparatus includes an engine RPM detecting unit for detecting the RPM of the engine, an engine RPM control unit for controlling the engine RPM, a pressure detecting unit for detecting the pressure in a fluid line connected between a hydraulic pump driven by the engine and main valves for actuating actuators, and a control unit for determining whether every main valve is in its neutral position, through a functional computation for a pressure value detected by the pressure detecting unit with a predetermined reference value, and controlling the engine RPM controlling unit to decrease the engine RPM when every main valve is determined as being in its neutral position.

Growing community of inventors

Changwon, South Korea

Myung Hoon Song