Abstract: Provided is a crane including a boom. The crane hoists a suspended load through a hook from a tip of the boom, and position adjustment control for causing a position of the hook and a position of the tip of the boom to be close to each other as viewed in a vertical direction is performed until the suspended load is separated from a ground surface from a start of a hoisting motion.

Abstract: Provided is a monitoring device for a winch drum of a crane, the device including: a monitoring unit that monitors whether or not an abrasion generation condition is satisfied for the winch drum; and a notification unit that performs notification based on satisfaction of the abrasion generation condition.

Abstract: Provided is a construction machine including a hydraulic system having a hydraulic pump, and a first hydraulic actuator and a second hydraulic actuator which are driven by hydraulic oil supplied from the hydraulic pump. The construction machine includes a first flow rate detector that detects a flow rate of drain hydraulic oil discharged from the first hydraulic actuator, a second flow rate detector that detects a flow rate of drain hydraulic oil discharged from the second hydraulic actuator, and an abnormality determination unit that determines abnormality of the first hydraulic actuator, based on a detection signal from the first flow rate detector, and determines abnormality of the second hydraulic actuator, based on a detection signal from the second flow rate detector. The first flow rate detector and the second flow rate detector each have a moving body.

Abstract: There is provided a periphery display device for a work machine, which displays a bird's-eye view image around the work machine. A display magnification of a region between a peripheral line having a turning radius of the work machine and an offset peripheral line surrounding the peripheral line is different from a display magnification of a region inside the peripheral line.

Abstract: A suspended load calculation device includes a detection unit configured to detect information for specifying a load suspended by a crane, a calculation unit configured to calculate the suspended load based on a value detected by the detection unit, and an acquisition unit configured to acquire a boom length, in which the calculation unit corrects the suspended load by a correction value corresponding to the boom length acquired by the acquisition unit.

Abstract: There is provided a crane including a main body, a tower derrickably supported by the main body, a jib derrickably supported by the tower, an assist member that assist the jib to move along a ground, and a determination unit that determines whether or not the jib is stopped when the tower is lowered in a lowering work state where the jib is assisted by the assist member.

Abstract: There is provided a crane winch device allowing a suspended load to freely fall due to a load thereof. The crane winch device includes a winch drum around which a rope for suspending the suspended load is wound, braking brake unit that brakes the winch drum, speed-increasing unit that performs speed-increasing assist of the winch drum in a direction of free fall acceleration when a braking force of the brake unit is smaller than a first threshold, and an adjustment unit that adjusts the first threshold.

Abstract: A crane includes a crane body, a boom, a hoisting winch, and a rope holding device pressing a rope wound around a drum of the hoisting winch against the drum. The rope holding device includes an oscillating arm whose proximal end is attached to a base of the hoisting winch using a support shaft and distal end oscillates in a direction close to or away from the drum, and a rope presser which is attached to a distal end of the oscillating arm, extends in an axial direction of the drum between a pair of flanges, and abuts against the rope wound around the drum. A weight member, which biases a distal end side of the oscillating arm in a direction close to the drum by the gravity with the support shaft as a fulcrum, is provided at the proximal end of the oscillating arm.

Abstract: There is provided a crane including a front member capable of derricking, a backstop disposed on a rear surface side of the front member so as to limit a standing operation of the front member, an angle sensor that detects an angle of the front member, an operation detection unit that detects whether or not the backstop is operated, and a controller that controls a derricking operation of the front member. In a case where the controller determines that the angle of the front member is equal to or larger than a predetermined angle, based on a detection signal output from the angle sensor, and determines that the backstop is not operated, based on a detection signal output from the operation detection unit, the controller stops the standing operation of the front member.

Abstract: A counterweight device including a base plate having a mounted counterweight, a hydraulic cylinder that raises/lowers the counterweight mounted on the base plate, a detachable frame connecting the base plate and a cylinder rod of the hydraulic cylinder, a first pin pivotably supporting the detachable frame with respect to the cylinder rod, a guide coupling portion guiding a free end side of the detachable frame to the rear end portion side of a turning frame in response to a stretching/shrinking state of the cylinder rod, and coupled to the turning frame below an upper end of the rear end portion, and a rail (guide member) guiding the free end side of the detachable frame in a direction parallel to a stretching/shrinking direction of the cylinder rod. The mounting table and the hydraulic cylinder may be supported by a rear end portion of a machine body frame of a construction machine.

Abstract: A counterweight device installed in a rear end portion of a machine body frame includes amounting table having amounted counterweight, a hydraulic cylinder that raises/lowers the mounting table, a connection structure that connects the mounting table and a cylinder rod of the hydraulic cylinder, a support member that supports the hydraulic cylinder on the mounting table via an oscillating spindle, a first coupling mechanism that couples the connection structure and the rear end portion of the machine body frame to each other at a position where an upper end of the rear end portion is lower than an upper end of the connection structure, a second coupling mechanism that couples the support member and the rear end portion of the machine body frame to each other, a first operation unit that operates the first coupling mechanism, and a second operation unit that operates the second coupling mechanism.

Abstract: In a work machine including an engine; a hydraulic pump; an actuator; an operating member that operates an actuator; an exhaust gas purifying device; a load application device that applies a load to an engine to raise the temperature of exhaust gas; and a control device, the load application device includes a load application valve that is provided in series between the hydraulic pump and the actuator and performs switching as to whether a hydraulic oil flow channel between the hydraulic pump and the actuator is brought into a communication state or a non-communication state in accordance with a control pressure, and if a load application request is input, the control device changes the control pressure exerted on the load application valve on the basis of the presence or absence of input of an operation signal of the operating member.

Abstract: A control device of a hydraulic winch includes an engine, a hydraulic pump, a hydraulic motor driving a winch drum, a winch manipulating member, an engine control unit controlling a rotation speed of the engine, a winch load detector detecting a load applied to the winch drum, and a motor capacity control unit controlling a motor capacity of the hydraulic motor so as to decrease a motor capacity of the hydraulic motor in a fuel-saving operation mode to a motor capacity which is smaller than a motor capacity of the hydraulic motor in a normal operation mode. The engine control unit sets an upper limit value of the rotation speed of the engine in the fuel-saving operation mode to a value which is lower than a maximum rotation speed of the engine in the normal operation mode and corresponds to the load detected by the winch load detector.

Abstract: A working machine includes a lower body, a turning body, a turning manipulating member which turns the turning body, a hydraulic motor which rotationally drives the turning body, a brake device which brakes the hydraulic motor, a main hydraulic source which supplies hydraulic oil to the hydraulic motor, and a direction control valve which controls a flow direction of the hydraulic oil according to the manipulated variable of the turning manipulating member, in which in a state where the hydraulic motor is braked by the brake device based on a manipulation of a brake manipulating member, when the turning manipulation is performed by the turning manipulating member, a brake applied to the hydraulic motor by the brake device is released with respect to turning in an indication direction indicated by the turning manipulation such that the turning body turns in the indication direction.

Abstract: A working machine with a crawler includes a lower traveling body having a pair of crawlers, an upper turning body, an extension beam installed rotatably to be parallel in a longitudinal direction of the crawler, a fitting portion opened in a side frame of the crawler, a fixing pin fixing the extension beam to the side frame, a fixing pin insertion hole, a fixing pin fitting hole, and a reinforcement rib, in which the extension beam extends to be inserted into the fitting portion, and the reinforcement rib is provided at a center portion of an opening of the fitting portion, and the fixing pin fitting hole is disposed at a position which is deviated from an imaginary center line extending along a longitudinal direction of the fitting portion from the center portion and does not interfere with the reinforcement rib.

Abstract: The crane includes a swing brake device installed between a hydraulic motor and a control valve and having a flow restrictor; a first backpressure detector detecting a motor backpressure between the flow restrictor and one of ports of the hydraulic motor; a second backpressure detector detecting a motor backpressure between the flow restrictor and the other port of the hydraulic motor; and a control device. The control device has an external-force direction estimation unit that estimates a swing direction of an upperstructure under an external force acting on the upperstructure on the basis of a motor backpressure detected by the first backpuressure detector and a motor backpressure detected by the second backpressure during an operating state of the swing brake device. The control device has a notification control unit that causes the notification device to provide notification of the estimated swing direction of the upperstructure.

Abstract: A crane includes: a boom; a jib; a front post that is swingably attached to a tip end side of the boom; a rear post that is swingably attached to the tip end side of the boom; a post-side pendant member, with one end of the post-side pendant member being attached to a tip end of the rear post; a boom-side pendant member, with one end of the boom-side pendant member being attached to another end of the post-side pendant member, and another end of the boom-side pendant member being attached to the boom; and a post driving device having a link mechanism that rotates the rear post in a range including a position at which the rear post is swung down to the front post side and a position at which the rear post is swung down to the boom side, while the boom is held down in a horizontal position.

Abstract: A cylinder retraction system causes a crawler side frame hoisting hydraulic cylinder, swingably suspended on a ventral surface side of a lower boom, to swing between a retracted attitude, in which the hydraulic cylinder is set along a ventral surface of the lower boom, and an operating attitude, in which the hydraulic cylinder is oriented along a vertical direction. As the rod of the hydraulic cylinder, currently having the operating attitude, is contracted by a predetermined extent, the rod front end of the hydraulic cylinder is guided by the guiding portion until the hydraulic cylinder takes on the retracted attitude. As the hydraulic cylinder, currently having the retracted attitude, is extended by a predetermined extent, engagement between the rod front end of the hydraulic cylinder and the guiding portion is released so as to allow the hydraulic cylinder to take on the operating attitude.

Abstract: A winch braking device includes: a brake; a brake pedal; a reaction force-imparting element that imparts a reaction force to the brake pedal; a rotation link that rotates by interlocking with the foot operation at the brake pedal; a brake valve linked to the rotation link, that applies a secondary pressure to the brake in response to the foot operation at the brake pedal; and a tension spring, with one end thereof attached to the vehicle body at a predetermined position and another end thereof attached to the rotation link, that applies a force to the brake pedal along a direction opposite a direction of the foot operation. As the foot operation is performed at the brake pedal, the tension spring extends and a shortest distance between a rotational center of the rotation link and a central axis of the tension spring becomes smaller.

Abstract: A control device for a hydraulic winch includes: a hydraulic source; a variable-displacement hydraulic motor; a winch operation member; an accelerator operation quantity detection unit; an engine control unit; a rotation speed detection unit; a line pull detection unit; a condition decision unit; and a motor displacement control unit, wherein: once the condition decision unit decides that the fuel-efficient, high-speed operation condition has been established, the engine control unit sets an upper limit to the engine rotation speed at a predetermined rotation speed, lower than the maximum rotation speed.