Abstract: A hydraulic circuit for heavy equipment is disclosed, which utilizes a hydraulic fluid supplied from a hydraulic pump for driving a cooling fan, as a pilot signal pressure, without installing a separate constant displacement pilot pump for supplying the pilot signal pressure to a control valve for controlling the hydraulic fluid to be supplied to a working device such as a boom.

Abstract: A pressure control valve for heavy equipment. The pressure control valve can smoothly operate a working device having a high load pressure by limiting a supply of hydraulic fluid to a working device having a low load pressure in the case of simultaneously operating a plurality of working devices in a hydraulic circuit in which a plurality of control valves (e.g., a boom control valve and a bucket control valve) are connected in parallel to a single hydraulic pump.

Abstract: A double check valve having a floating function is disclosed, which can prevent construction equipment from overturning through intercepting of a floating function even if a signal pressure is fed to the double check valve to perform the floating function in a state that an excavator is supported by a working device (e.g. a dozer blade), i.e. in a jack-up state, on a sloping site and so on.

Abstract: An upper frame for an excavator is provided to smoothly transmit the load and shock which is transmitted through a mounting portion of a working device during operation (e.g., a lifting operation mode), to an upper frame by integrally installing a bracket for mounting a fuel tank or the like on an upper plate of the upper frame. The upper frame includes a center frame having a bottom plate and a pair of side plates and vertically welded to the bottom plate, a left side frame welded to the side plate of the center frame, a right side frame welded to the side plate of the center frame, an upper plate placed in the front of the center frame for supporting a bracket for a working device, to which a boom is pivotally secured, and an extended member integrally extended from one end of the upper plate for supporting desired parts.

Abstract: A flow control apparatus for heavy construction equipment is provided, which can prevent overspeed and abrupt operations of an actuator due to an excessive flow rate during an initial operation of the actuator when a composite work is performed by simultaneously operating an option device and another actuator, and can prevent the cut-off of hydraulic fluid supply to the option device due to an operation inability of a flow control valve when leakage of the hydraulic fluid occurs due to the increase of the temperature of the hydraulic fluid.

Abstract: An operator cab for heavy equipment is disclosed to prevent a sliding door mounted on the cab from rocking or rattling in X, Y, and Z-axis directions due to a shock or vibration applied to the cab in a state that the sliding door is fully opened or closed.

Abstract: 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.

Abstract: A disk brake includes a set of brake disks, which includes a set of rotor disks and a set of stator disks, which are arranged so that every other brake disk includes a stator disk and every second disk includes a rotor disk. The brake disks are displaceable in relation to one another along a central axis for engagement and disengagement with one another. There is a layer of coating material on at least one of the sides of the stator disk for engagement with the adjacent rotor disk.

Abstract: An excavator mounted with tanks having side doors. Bend-formed side doors are mounted on outer sides of a hydraulic fluid tank and a fuel tank that are welded structures mounted on an upper frame of the excavator, have the same curved surfaces as an external shape of the equipment, so that no precise tank manufacturing work is required and welded portions of the tanks are prevented from being exposed to an outside.

Abstract: A reinforced upper frame for supporting a cabin of heavy construction equipment using a welding deformation preventing structure and a method of manufacturing the same are disclosed, in which even if a side frame is welded to a machined center frame, there is no thermal deformation around the machined portion. The reinforced upper frame includes a center frame having a lower plate machined to accommodate a swing ring gear, a lateral plate machined to accommodate an operation device, and a welding deformation preventing structure fixed to one side of the lower plate and lateral plate prior to welding, in which a part of the cabin is mounted on the welding deformation preventing structure, and left and right frames each having a side channel disposed in a longitudinal direction of the center frame and a side frame welded to the structure for connecting the side channel and the center frame.

Abstract: An apparatus for collecting condensed water of an air conditioner evaporator in heavy construction equipment is disclosed, which is able to receive condensed water into a receiver from an evaporator and treats the same which comprises a body which is installed at one side of the evaporator and includes a plurality of support frames provided in the interior of the same, with its upper and lower sides being fixed with a vibration resistant member; a water collection pipe which allows the condensed water produced from the evaporator to be supplied to a water inlet valve; a storing tank which is connected with the water inlet valve and stores condensed water inputted via the water inlet valve; a water purification filter which filters dirt, heavy metallic substances and organic chemicals contained in the condensed water supplied from the storing tank; and a water purification tank which stores the filtered condensed water and has a pipe extended to the outside of the body.

Abstract: Provided is a construction equipment cab having a protective structure capable of protecting an operator from injury due to deformation of a cab in the event of a rollover accident. The construction equipment cab is mounted on an upper swivel body, and the protective structure is mounted on the cab and the upper swivel body and protects an operator from the cab in a rollover accident. The construction equipment cab includes a lower panel provided at a rear lower portion of the cab to be sunk in a forward direction in order to secure a space in which the protective structure is held, and a unit for fixing the protective structure held in the space to the upper swivel body and the cab.

Abstract: A hydraulic circuit for construction equipment is disclosed, which can prevent an abrupt rotation of a swing device when a switching valve for the swing device is shifted in a state that switching valves for a traveling device and a working device have been shifted.

Abstract: A leveling apparatus for excavator and forestry machine equipment. The leveling apparatus is mounted between an upper swing structure and a lower frame formed on a lower driving structure including a swing bearing, left and right track chassis, and a front arm and a rear arm connected to upper parts of the track chassis. The leveling apparatus can keep a horizontal level of the upper swing structure against an inclined ground.

Abstract: A console box for heavy equipment having a safety bar with a function sound device is provided, which generates a function sound when an operator rotates a safety bar to be in a horizontal/vertical direction, so that the operator can accurately recognize the rotation state of the safety bar.

Abstract: A method for preventing overturning a dump vehicle, the vehicle including a forward vehicle section with a forward frame and a wheel axle supported by the frame. The dump vehicle further includes a rear vehicle section with a rear frame and at least one wheel axle supported by the frame. The dump vehicle further includes an articulation joint, which connects the forward frame and the rear frame and allows the forward frame and the rear frame to pivot in relation to each other about an axis extending in a longitudinal direction of the vehicle. During a tilting procedure for unloading material from a container of the dump vehicle, the method includes determining if there is a risk for a pair of wheels of the wheel axle of the forward vehicle section to lose ground contact or if the pair of wheels have already lost ground contact.

Abstract: Heavy equipment having a tool box opening in forward direction of the equipment is provided, in which a tool box door mounted on an upper frame of an excavator can be simply opened and closed through pressing of a button, an auxiliary structure, such as a handrail that is used when an operator ascent toward an engine room, is not required, and the shape of the tool box door can be freely designed to sufficiently secure storage space.

Abstract: The invention relates to a drive system for a vehicle driveline comprising a pair of interconnected first transverse drive shafts (31a, 31b) extending in opposite directions, each of which supports a ground engaging member, and a first arrangement (101) allowing said pair of first transverse drive shafts to rotate at different speeds. Said arrangement (101) comprises a pair of individually selectively engagable clutches (37a, 37b), one clutch for each transverse drive shaft, and each of said clutches (37a, 37b) is configured for engaging and disengaging, respectively, the associated transverse drive shaft (31a, 31b) to a driving connection with a source of motive power.

Abstract: An apparatus for cooling overheated gas generated from a diesel particulate filter which is connected between a diesel engine and an exhaust pipe of the diesel engine is disclosed. The apparatus includes a tail pipe for discharging outwardly the overheated gas discharged from the diesel particulate filter, a cooling fan, provided at one side of an engine room, for generating an air stream by sucking ambient air, and a diffuser enclosing an outer circumference of the tail pipe in such a way a space is formed between the diffuser and the tail pipe to prevent the diffuser from directly contacting the tail pipe. The engine room is provided with a through-hole penetrating one side of the engine room, and the tail pipe has one end connected to the diesel particulate filter, and the other end extended outwardly from the engine room through the through-hole.

Abstract: An engine revolution speed control system for a construction machine is disclosed. The engine revolution speed control system includes an input unit that sets an engine revolution speed by a user, outputs a setting process as a set signal, and determines whether or not an engine is driven at a set engine revolution speed; a control unit that receives the set signal and stores the set engine revolution speed, receives the set signal and an ON/OFF signal to output an output signal corresponding to the received set signal and the ON/OFF signal, and controls operation of the engine at the set engine revolution speed in accordance with the ON/OFF signal; and a display that receives the output signal to visually output the setting process or whether or not the engine is driven at the set engine revolution speed.