Volvo Construction Equipment Ab

Jae Hoon Lee

Dong Soo Kim

Jae Hong Kim

Chun Seung Lee

Eun Tae Jeung

Joong Seon Joh

Dong Soo 103-1306 Kyunghwa The Sharp Apt Kim

A traveling system for construction equipment is provided, which can secure an initial traveling manipulability regardless of a low-speed traveling or a high-speed traveling. If the high-speed traveling is selected and the traveling is manipulated, the inclination angle of a swash plate of a hydraulic pump is variably controlled, so that the discharge flow rate of the hydraulic pump exceeds a predetermined flow rate in comparison to the low-speed traveling.

Traveling system for construction equipment

A traveling device for crawler type heavy equipment is provided, which can improve manipulability by preventing an abrupt decrease/increase of a traveling speed of the equipment when a combined operation, in which a left/right traveling device and a working device are simultaneously driven, is performed. The traveling device for crawler type heavy equipment includes a variable orifice shifted to intercept the supply of the hydraulic fluid toward the traveling device in response to the signal pressure in the combined working mode if a load pressure of the working device is relatively higher than that of the traveling device.

Traveling device for crawler type heavy equipment

An apparatus for easing an impact on a boom of an excavator and a method of controlling the same are disclosed, which can minimize the vibration occurring in the boom due to the impact on a boom cylinder by actively controlling an amount of hydraulic fluid being supplied to the boom cylinder when the operation of the boom cylinder is suddenly stopped due to an operator's sudden manipulation of an operation lever for a working device. The apparatus includes first and second hydraulic pumps; a boom cylinder; a main control valve; an operation lever for supplying pilot signal pressure to a spool of the main control valve when an operator manipulates the operation lever; operation lever detection means for detecting boom up and boom down signal pressures according to an amount of manipulation of the operation lever; boom cylinder pressure detection means for detecting pressures generated in a large chamber and a small chamber of the boom cylinder; a controller for calculating and outputting a control signal of the main control valve if the boom cylinder has been suddenly stopped; and boom vibration preventing means for controlling the pilot signal pressure being supplied from the second hydraulic pump to the main control valve.

Apparatus for easing impact on boom of excavator and method of controlling the same

In the present invention, it is possible to supply hydraulic fluid by the amount needed in an option tool even when a combined work is performed by engaging an option tool having a different operation pressure to a work apparatus. The hydraulic circuit for an option tool of heavy equipment comprises a poppet valve which is openably and closably installed in a flow path of a supply side of the option tool spool, a first spool which is installed in a flow path between the poppet valve and the option tool spool and has an opening portion adapted to maintain a constant pressure difference when the first spool is switched by pilot pressure discharged from the pilot pump, and a second spool which is installed in a down stream side of the poppet valve and is switched when an over load occurs due to an over pressure exceeding the degree set in the option tool for thereby closing the poppet valve.

Hydraulic circuit for option tool of heavy equipment

There is provided a hydraulic circuit for an option apparatus of heavy equipment using a boom confluence spool, comprising a poppet valve installed at a flow path of a supply side of a spool for the option apparatus, a boom confluence spool that controls the flow rate supplied to the option apparatus and work apparatus and is installed at a direct upstream of the spool of the option apparatus, a second electromagnetic proportion reducing valve that is installed at a flow path between the pilot pump and the boom confluence spool and outputs a secondary pressure in response to an electric signal from the controller and controls the boom confluence spool, and a first spool that is installed at a downstream of the poppet valve and is switched when a pressure difference between upstream and downstream of the boom confluence spool is larger than a set value.

Growing community of inventors

Changwon-si, South Korea

Jae Hoon Lee