摘要:
Provided are a raisable-lowerable member capable of shortening a time required for assembling and disassembling of a crane, and a crane comprising the raisable-lowerable member. The raisable-lowerable member comprises: a boom attachable to an upper slewing body of the crane turnably about a boom-pivot-turn-axis in a raising-lowering direction; and a mast to be driven so as to be turned about a mast pivot-turn-axis parallel to the boom-pivot-turn-axis. The boom includes a boom body, a boom foot joined to a basal end of the boom body and adapted to be attached to the upper slewing body turnably about the boom-pivot-turn-axis, and a mast mounting portion joined to the basal end of the boom body. The mast has a basal end which includes a mast foot to be attached to the mast mounting portion turnably about the mast pivot-turn-axis.
摘要:
Provided is an apparatus to lower a load, comprising a hydraulic pump, a hydraulic actuator having first and second ports, a manipulation device, a hydraulic circuit including meter-in and meter-out flow passages for the first and second ports respectively and a regeneration flow passage with a check valve, a control valve, a meter-out flow controller adjusting a meter-out flow rate according to the manipulation device, a back pressure valve, and a non-regeneration operation relief valve whose set pressure is not less than a sum of a minimum set pressure of the back pressure valve, an inlet-outlet pressure difference of the meter-out flow controller when the meter-out flow rate is maximum and a discharge flow rate of the hydraulic pump is maximum, and an actuator pressure difference for driving the hydraulic actuator with no load, and not less than a maximum set pressure of the back pressure valve.
摘要:
Disclosed is a raisable-lowerable member which comprises a boom and a jib. The boom comprises a first supporting portion configured to rotatably support a jib foot when the jib is set in a protruding posture; and a second supporting portion configured to rotatably support a supportable portion of the jib when the jib is set in an enfolded posture. A position adjusting and holding unit of the jib is configured to couple, to the frame, a specific site of the second link in such a manner that a relative position of the second link with respect to the frame in a rotational direction of the second link is adjustably changed to allow the rotational axis of the second joint portion to become coincident with the rotational axis of the jib foot, and to hold the second link at the changed relative position.
摘要:
A crane operation evaluation device for evaluating an operation status of an operator of a crane performing a crane work by using drive power of an engine. The crane operation evaluation device includes: a display device provided at a position of the crane that is visible to the operator and serving to display predetermined data; a detector for detecting a state of a given part of the crane; and a data control unit that, after a stopping operation of the engine, derives a first fuel consumption index for analyzing a fuel consumption efficiency of the crane work performed between the most recent start of the engine and the stop of the engine by the stopping operation and a first work index for analyzing content of such crane work, on the basis of detection data of the detector, and causes the display device to display the derived first fuel consumption index and first work index.
摘要:
A slewing stop control apparatus and method, capable of executing, while performing the control of determining the target slewing velocity based on a remaining slewing angle from the actual slewing motion position up to the slewing stop angular position, an automatic control of re-slewing the slewing structure having been stopped before the slewing stop angular position. The apparatus executes slewing angular velocity control for deciding the slewing braking start timing to stop the stewing structure at a slewing stop angular position in accordance with a predetermined slewing deceleration and the subsequent target slewing angular velocity, based on the remaining slewing angle of the slewing structure. When the slewing structure stops before the slewing stop angular position due to disturbance despite the foregoing control, the target slewing angular velocity is corrected to be increased for generating slewing torque to restart the slewing.
摘要:
An engine control apparatus includes a governor and a controller which derives a lever operation-related rotational speed control target value derives an accelerator operation-related rotational speed control target value-corresponding to a detected operation amount of the accelerator member, based on an accelerator operation/rotational speed correlation function defining a relationship between the rotational speed control target value and the operation amount of the accelerator member; performs a lower value selection for selecting a lower one of the derived lever operation-related rotational speed control target value and accelerator operation-related rotational speed control target value; and causes the governor to control the rotational speed of the engine such that the rotational speed of the engine is set to the rotational speed control target value selected by the lower value selection.
摘要:
In a crawler crane of the present invention, a plurality of winches 11-14 for winding wire ropes are disposed on a rotating frame 6 of an upper rotating body 3 in a row in a plane view. A cabin 17 and a power unit 18 are disposed on the front and rear portions of either a right side or a left side of the rotating frame 6 of the upper rotating body 3. A working oil tank 36 of the power unit 18 is disposed between the cabin 17 and a driving section 31-34 of the power unit and in close proximity to a rear surface of the cabin 17. The working oil tank 36 is formed in a size which covers the substantially whole area of the rear surface of the cabin 17. In the crawler crane of the present invention, it is possible to take an anti-sound measure for the cabin to a satisfactory extent without causing cost increase. In the crawler crane of the present invention, moreover, it is possible to improve the transportability because the width of the upper rotating body can be shortened.
摘要:
In a crawler vehicle according to the present invention, at the time of crane operation at a place where a grounding space of crawlers is limited, a land leveling preparation is suppressed as less as possible so as to improve efficiency of the operation. The crawler vehicle according to the present invention has a high performance. The crawler vehicle according to the present invention is provided with a pair of left and right crawler frames on the both left and right sides of a track frame. The crawler frames can be moved between an expansion position for maximizing a distance between centers of the crawlers and a contraction position for minimizing the distance. Further, the crawler vehicle according to the present invention can position the crawler frames to the track frame at an intermediate position in the middle of the expansion position and the contraction position.
摘要:
A construction machine includes a vertical separating/connecting device interposed between a lower traveling body and a swing bearing that supports an upper rotating body. The device includes an externally toothed ring member fixed to the swing bearing with a first attaching unit, a rotating unit that rotates the externally toothed ring member, an internally toothed ring member fixed to the lower traveling body with a second attaching unit positioned on an attachment pitch circle having the same diameter and center as an attachment pitch circle of the first attaching unit, and a fixing unit that fixes the externally toothed ring member or the internally toothed ring member. Internal teeth of the internally toothed ring member and external teeth of the externally toothed ring member are positioned so as to allow the movement of the external teeth or to engage with each other when the externally toothed ring member is rotated.
摘要:
A traveling crane according to the present invention includes a hook hoisting guide sheave for guiding a hook hoisting rope from the top of a boom toward the end of a jib, and the hook hoisting guide sheave is arranged on the top of the boom in a state that the guide sheave can guide the hook hoisting rope along the upper surface of the boom by folding the rope toward an upper spreader placed at a position adjacent to a boom anchor during assembling/disassembling of the crane. Thereby, the upper spreader can be moved between the boom anchor and a far end of the boom without providing a guide sheave dedicated for moving the upper spreader. Pairs of support legs are downward provided on both sides and in front and in rear of the upper spreader and a roller is provided for each support leg, so that interference between the upper spreader during movement and obstacles on the boom upper surface can be prevented even in a horizontal movement system excellent in operating efficiency.