A rotary working vehicle is provided with: a lower traveling body; an upper rotating body; a rotating frame constituting the bottom of the upper rotating body; a boom bracket supported by the rotating frame so as to be capable pivoting horizontally; a first vertical plate and a second vertical plate, which are raised from the bottom plate of the rotating frame; a swing cylinder provided on the opposite side of the second vertical plate from the first vertical plate and connecting the rotating frame and the boom bracket; a protrusion piece protruding toward the swing cylinder from a side wall of the second vertical plate above the swing cylinder; a hose guide provided to the protrusion piece; and first and second hydraulic hoses which pass above the first vertical plate and the second vertical plate, extend downward from above through the hose guide, and reach the swing cylinder.

A swing motion control system for an earth-moving machine may include a closed loop hydraulic circuit including a hydrostatic swing pump fluidly coupled to at least one hydraulic swing motor configured to control a swing mechanism of the earth-moving machine, a pressure control device configured to control the pressure of fluid supplied to the hydrostatic swing pump for control of the pressure output by the pump, and a controller. The controller may be configured to monitor and process signals received from sensors and operator input, wherein the signals received from the sensors are indicative of machine position and pose, and inertia mass of swing components and a payload being moved by the swing mechanism of the machine, and control at least one of an offset amount for desired pump displacement by the hydrostatic swing pump or an offset amount for pump output pressure from the hydrostatic swing pump based on at least one of an amount of slope on which the machine is operating or the inertia mass of the swing components and payload.

To provide a working machine including a lower travelling body and an upper slewing body disposed in a slewable manner with respect to the lower travelling body, the working machine being capable of more reliably preventing the upper slewing body from coming into contact with an obstacle existing around the working machine. The working machine includes a detection device, a position identification device, and a movement control device. The position identification device includes a calculation section, a conversion section, and an identification section. The movement control device controls the movement of the upper slewing body in such a way as to prevent the upper slewing body from coming into contact with the obstacle based on the position of the obstacle relative to the virtual boundary surface, the position being identified by the identification section.

It is determined whether a velocity estimation model is established from an actual operating velocity Vr and a target operating velocity Vt of each of actuators 20A, 21A, and 22A; in a case in which the velocity estimation model is established, a dynamic center-of-gravity position of a hydraulic excavator 1 in a case in which each of the actuators 20A, 21A, and 22A is suddenly stopped from a driven state is predicted from an estimated operating velocity Ve; in a case in which the velocity estimation model is not established, the dynamic center-of-gravity position is predicted from the actual operating velocity Vr and it is determined whether to execute control intervention using the predicted dynamic center-of-gravity position; and in a case in which it is determined to execute the control intervention, the target operating velocity Vt is corrected in such a manner that each of the actuators 20A, 21A, and 22A slowly decelerate. It is thereby possible to appropriately carry out operating velocity limiting on a front work implement 2 and slow deceleration of the front work implement 2 and to suppress reductions in workability and operability, a deterioration in a ride quality, and the like even in a case of work involving an abrupt change in disturbance or a change in the lever operation amount within minute time.

To provide a small hydraulic excavator, which even may have an upperstructure formed such that at least its rear end swings within a body width range and having a limited installation space for devices, that allows an accumulator to be disposed and allows the accumulator to be protected from external force generated during work. The present invention relates to a rear small-swing type mini excavator that includes an accumulator 30 accommodating and recovering potential energy and hydraulic energy used by at least one of drives of an undercarriage 1, an upperstructure 2 formed such that its rear end swings within the body width range of the undercarriage 1, and a working device 3. In the rear small-swing type mini excavator, the accumulator 30 is disposed between a valve block 26 and a front longitudinal board 41 of a longitudinal board member included in a main frame 10 along the front longitudinal board 41, and a pipe connected to the accumulator 30 and the valve block 26 is disposed closer to the accumulator 30 and the valve block 26.

Work efficiency is improved while necessary and sufficient monitoring on the surroundings of a working machine is performed. A working machine includes an undercarriage 132 on which an upperstructure 131 including a front working device is mounted in a swingable manner, and includes a surrounding monitoring device 200 that monitors surroundings. The surrounding monitoring device 200 has an information controller 161 that: sets a working region by use of terrain data and work states received from sensors detecting work states of the front working device of the working machine; calculates proximity for each of the obstacles around the working machine by use of the working regions and relative positions of each of obstacles and the working machine, the obstacles being detected by an obstacle sensor that detects obstacles around the working machine; and outputs a control instruction in accordance with the proximity.

A hydraulic system is capable of improving the acceleration performance of a slewing motor and suppressing an increase in the flow rate of hydraulic fluid supplied to the slewing motor. The hydraulic system includes a slewing speed sensor that detects a slewing speed of a slewing body and a controller that controls a slewing motor capacity, which is a capacity of the slewing motor. The controller controls the slewing motor capacity so as to make the slewing motor capacity when the slewing speed is in a low speed range be greater than the slewing motor capacity when the slewing speed is in a high speed range.

A rotary working vehicle is provided with: a lower traveling body; an upper rotating body; a rotating frame constituting the bottom of the upper rotating body; a boom bracket supported by the rotating frame so as to be capable pivoting horizontally; a first vertical plate and a second vertical plate, which are raised from the bottom plate of the rotating frame; a swing cylinder provided on the opposite side of the second vertical plate from the first vertical plate and connecting the rotating frame and the boom bracket; a protrusion piece protruding toward the swing cylinder from a side wall of the second vertical plate above the swing cylinder; a hose guide provided to the protrusion piece; and first and second hydraulic hoses which pass above the first vertical plate and the second vertical plate, extend downward from above through the hose guide, and reach the swing cylinder.

A hydraulic excavator includes: a revolving frame; a work implement including a first actuator and a second actuator; a control valve; and a first pipe through which hydraulic oil flows between the control valve and each of the first actuator and the second actuator. The first pipe includes: a first conduit connected to the control valve; a second conduit and a third conduit that are connected to the first actuator and the second actuator, respectively; and a first branch portion at which the first conduit branches into the second conduit and the third conduit. A first region and a second region are on one side and the other side respectively with respect to the virtual straight line passing through a center of swing of the revolving frame. In the first region, a work implement is disposed. In the second region, the control valve and the first branch portion are disposed.

A process for execution by a processor of an electronic control unit (ECU), comprising: (a) detecting an operator command to align an upper structure of a tracked vehicle relative to a lower structure of the tracked vehicle; (b) in response to detection of the operator command, applying controlled rotation of the upper structure relative to the lower structure about an axis to align the upper structure relative to the lower structure at a predetermined relative angle; (c) in response to the upper structure having been aligned relative to the lower structure at the predetermined relative angle, signaling that alignment has been achieved; and (d) causing rotation of the upper structure to stop when alignment has been achieved and being non-responsive to further detection of the operator command during and for a predetermined period of time after said signaling. Also, a tracked vehicle comprising an ECU that executes the above process.