In a construction machine where an arm, a working attachment, and a distal end portion of an extensible cylinder are coupled via a power link and an idler link, to achieve protection of a grease feeding piping when the grease feeding piping is arranged in the idler link, and to ensure that the structure of the idler link is not complicated. In an idler link, there is formed a protruding part which protrudes in a direction opposite to a bucket from a link body part of the idler link; there is provided a grease feeding piping arrangement space which extends in a link length direction, toward right and left inside of right and left outer side faces of the protruding part, with at least either one side of the side opposite to the bucket or right and left inward sides open; and a grease feeding piping is arranged in the grease feeding piping arrangement space, in a state of not protruding in a direction opposite to the bucket beyond a protruding distal end portion face of the protruding part and not protruding toward right and left inside beyond right and left inner side link faces of the link body part.

A hydraulic system for a work machine includes a tank to store an operation fluid, a hydraulic device to be operated by the operation fluid, a control valve to control the hydraulic device, a first fluid tube connecting the hydraulic device and the control valve, the first fluid tube being to supply the operation fluid from the control valve to the hydraulic device, a second fluid tube branching from the first fluid tube and connected to the tank, a switch valve provided to the second fluid tube, the switch valve being to control a flow rate of the operation fluid, and an oil cooler provided to the second fluid tube between the switch valve and the tank.

An amphibious platform vehicle-vessel to support and to move hydraulically operated and controlled earth-moving and lifting equipment, such as excavators and cranes, on solid ground, semi-solid or marshy ground, shallow water, and deeper water. The modular units can be transported to a worksite on separate trailers and assembled and reconfigured on site. Two compartmented pontoon units are mounted to an adaptive cross member that can accommodate different types of moving-lifting equipment through different mounting flanges, and to auxiliary cross members. Propulsion is provided through amphibious cleats on drive chains in chain tracks driven by dual-motor driving drums and over a tension-adjusting passive chain roller, surrounding a sealed pontoon shell internally reinforced with bulkhead partitions, beam shell-bottom stiffeners, and pressed-angle shell-bottom stiffeners. An extendable auxiliary float can be extended outward from each compartmented pontoon for increased stability in floating operations.

A working machine includes a ground engaging structure, and an undercarriage supported on the ground engaging structure. The undercarriage has a drive arrangement for moving the ground engaging structure to propel the working machine, the drive arrangement comprising a prime mover and a transmission comprising a hydraulic pump arrangement configured to be driven by the prime mover. A superstructure rotatably mounted to the undercarriage and a working arm is connected to the superstructure. A first implement mount connected the undercarriage for operably mounting a working implement to the undercarriage. The undercarriage has a first actuator for raising and lowering a working implement when mounted to the first implement mount and comprises a hydraulic connector for supplying hydraulic fluid to the first actuator to actuate the first actuator, and a first auxiliary hydraulic connector is provided that is configured for supplying hydraulic fluid to an implement connected thereto.

An amphibious platform vehicle-vessel to support and to move hydraulically operated and controlled earth-moving and lifting equipment, such as excavators and cranes, on solid ground, semi-solid or marshy ground, shallow water, and deeper water. The modular units can be transported to a worksite on separate trailers and assembled and reconfigured on site. Two compartmented pontoon units are mounted to an adaptive cross member that can accommodate different types of moving-lifting equipment through different mounting flanges, and to auxiliary cross members. Propulsion is provided through amphibious cleats on drive chains in chain tracks driven by dual-motor driving drums and over a tension-adjusting passive chain roller, surrounding a sealed pontoon shell internally reinforced with bulkhead partitions, beam shell-bottom stiffeners, and pressed-angle shell-bottom stiffeners. An extendable auxiliary float can be extended outward from each compartmented pontoon for increased stability in floating operations.

Provided is a construction machine with which it is possible to shorten a duct for an air conditioning device disposed in a driver's cab, and to secure space for disposing a hydraulic hose, a control valve and the like under the floor of the driver's cab. A hydraulic excavator 1 is provided with a cabin 6 covering an maneuvering unit 5, a turning frame 7 on which the cabin 6 is mounted, and an air conditioning device 8 for air conditioning the inside of the cabin 6, wherein: the turning frame 7 includes a cabin installation portion 7a in which the cabin 6 is installed; the cabin installation portion 7a includes a box-shaped right frame 72d having a first opening portion 731 and a second opening portion 732 that communicate with one another, and an air conditioned air discharge opening of the air conditioning device 8 communicates with the first opening portion 731.

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 swivel joint for a construction machine can detect a slewing angle of an upper slewing body and has a high maintainability. The swivel joint includes a body, a stem, a lower cover, and a sensor unit. The sensor unit includes: a rotation angle sensor fixedly attached to an upper end of the stem; and a rod having a distal end provided with a detection target to be detected by the rotation angle sensor and a proximal end fastened to the lower cover. The stem is formed with: a rod insertion hole for receiving the rod to be inserted therethrough; and a stem-side drain oil passage for allowing a drain oil to pass therethrough.

A hose retention system for a negative-angle-capable blasthole drilling machine is disclosed. The hose retention system may include an upper cage to extend longitudinally along a mast structure. The upper cage may have a secured end to couple the upper cage to the mast structure, a free end to extend toward the mast structure, and a first longitudinally-extending channel. The hose retention system may include a lower cage separate from the upper cage to extend longitudinally along the mast structure. The lower cage may have a secured end to couple the lower cage to the mast structure, a free end to extend toward the mast structure, and a second longitudinally-extending channel.

A working machine is provided, which includes a prime mover, a first traveling pump driven by power of the prime mover to supply operation fluid through a connector fluid tube, a traveling motor including first and second ports connected to the connector fluid tube, the traveling motor configured to be switched in a first speed and a second speed higher than the first speed, a first pressure detector to detect first traveling-pump pressure near the first port, a second pressure detector to detect second traveling-pump pressure near the second port, and a controller configured, with the traveling motor switched in the second speed, to automatically shift down the traveling motor from the second speed to the first speed, when a differential pressure between the first traveling-pump pressure and the second traveling-pump is equal to or more than a deceleration threshold.