Abstract: Disclosed is a work machine having a traveling apparatus and a work implement driven by an engine. A hydraulic system mounted on the work machine includes an HST pump comprising a swash plate, variable displacement pump driven by the engine, an HST motor connected in a closed circuit to the HST pump and a pair of speed-changing oil passageways, the HST motor being driven by an amount of oil supplied by the HST pump, thereby to drive the traveling apparatus, a main pump driven by the engine, the main pump supplying pressure oil to the work implement, a pilot pump driven by the engine, a swash plate positioning circuit configured to effect positioning of a swash plate of the HST pump with pilot oil supplied from the pilot pump, and a bleed circuit configured to drain, via a throttle, a portion of the pilot oil supplied to the swash plate positioning circuit.

Abstract: A wheeled work machine in which the center of gravity of a machine body is positioned low and the stability of the machine in a working position is secured without regard to the movement of the center of gravity caused by the rotation of a rotation table during work. An operation body (111) integrally rocking with a front axle case (96) is provided at the center in the left-right direction of the front axle case (96), and a rocking lock mechanism (112) for limiting the rocking of the operation body (111) is provided at a machine body frame (6). The rocking lock mechanism (112) has a lock cylinder (115) in which a piston rod (120) is horizontally fixed to the machine frame (6) and a switchover valve (118) for switching two oil chambers (124A, 124B) of the lock cylinder (115) between a communicated state and a closed state. A cylinder tube (116) of the lock cylinder (115) is operably connected to the operation body (111).

Abstract: An improvement of a loader work machine is disclosed. A machine body frame includes a frame body having a bottom wall and a pair or right/left side walls, and a pair of right/left support frame members connected to a rear end of the frame body. A cabin is mounted on the machine body frame. A transverse connecting member is disposed rearwardly of the cabin for connecting the pair of right/left support frame members to right/left sides thereof, respectively. A pair of right/left arms are disposed on right/left sides of the machine body frame, with base portions thereof being vertically pivotally supported to the pair of right/left support frame members, respectively. A pair of right/left arm cylinders are provided between the base portions of the arms and the rear portions of the machine body frame for lifting up/down the arms. A hood is provided at the rear end of the frame body and downwardly of the transverse connecting member between the pair of right/left support frame members, for housing an engine.

Abstract: A loader work machine includes: a first lift link (81) and a second lift links (82) disposed forwardly of the first lift link (81) for vertically pivotally supporting a base portion of an arm (77) at a rear upper portion of a machine body frame (1); an arm cylinder (79) provided between the base portion of the arm (77) and a rear lower portion of the machine body frame for lifting up/down the arm (77); a first link support shaft (85) for pivotally supporting a lower base portion of the first lift link (81) to the machine body frame (1); a second link support shaft (86) for pivotally connecting a base portion of the second lift link (82) to the machine body frame (1), at a position forwardly of the first link support shaft; a first arm support shaft (88) for pivotally supporting a base portion of the arm (77) to an upper free end of the first lift link (81); a second arm support shaft (89) for pivotally connecting a base portion of the arm (77) to a free end of the second lift link (82), at a position forwardl

Abstract: A wheel loader having good operability. The wheel loader has a machine body travelably supported on wheels; a working device supported on the machine body, the working device having a boom swingably supported at its base end side on the machine body, an arm swingably supported at and connected to the forward end side of the boom, and a working tool swingably provided on the forward end side of the arm; travel operation means for performing travel operation of the machine body; and a brake for braking, when the travel operation means is not operated and the arm is swung, the wheels in operative association with the swing of the arm.

Abstract: A wheel type work machine having improved ease of assembly and a compact-sized traveling system power transmission mechanism. The wheeled work machine comprises a traveling body (2) having an engine (7) mounted at the rear of a machine frame (6) supported by front and rear wheels (4, 5) and the traveling system power transmission mechanism (8) for transmitting power from the engine (7) to the rear wheels (5). The traveling system power transmission mechanism (8) comprises a rear wheel differential device (38) disposed on the front side of the engine (7), a hydrostatic transmission (35) disposed on the front side and the rear wheel differential device and receiving the power from the engine (7), and a mechanical transmission device (37) disposed between the hydrostatic transmission (35) and the rear wheel differential device (38) and transmitting the power from the hydrostatic transmission (35) to the rear wheel differential device (38).

Abstract: A wheeled work machine in which the center of gravity of a machine body is positioned low and the stability of the machine in a working position is secured without regard to the movement of the center of gravity caused by the rotation of a rotation table during work. An operation body (111) integrally rocking with a front axle case (96) is provided at the center in the left-right direction of the front axle case (96), and a rocking lock mechanism (112) for limiting the rocking of the operation body (111) is provided at a machine body frame (6). The rocking lock mechanism (112) has a lock cylinder (115) in which a piston rod (120) is horizontally fixed to the machine frame (6) and a switchover valve (118) for switching two oil chambers (124A, 124B) of the lock cylinder (115) between a communicated state and a closed state. A cylinder tube (116) of the lock cylinder (115) is operably connected to the operation body (111).

Abstract: A wheeled work vehicle includes a traveling body including front and rear wheels, a traveling drive unit having an engine and a power transmission mechanism, a fuel tank, a work oil tank, and a vehicle frame mounting the front and rear wheels, the traveling drive unit, the fuel tank and the work oil tank. The vehicle includes a swivel base disposed upwardly of the traveling body and mounted via a swivel bearing on the traveling body, a driver's seat mounted on a rear portion of the swivel base, a steering unit disposed forwardly of the driver's seat and a ground-work implement supported on an implement support unit. The vehicle frame includes a front region mounting a front-wheel suspension unit for the front wheels, a rear region mounting a rear-wheel suspension unit for the rear wheels and an intermediate region supporting the swivel bearing.

Abstract: A wheeled work vehicle includes a traveling body including front and rear wheels, a traveling drive unit having an engine and a power transmission mechanism, a dozer unit disposed at least at a front portion of front and rear portions of the body, a fuel tank, a work oil tank, and a vehicle frame mounting said members of the traveling body, a swivel base disposed upwardly of the traveling body and mounted via a swivel bearing on the traveling body to be swivelable for full-angle swiveling movement relative thereto, a driver's seat mounted at a rear portion of the swivel base, a steering unit disposed forwardly of the driver's seat, and a ground-work implement supported on an implement support unit disposed erect on a front portion of the swivel base to be pivotable in the right/left direction.

Abstract: A steering apparatus for a working vehicle is provided which is capable of steering dirigible wheels by increased steering angles while checking sideways sliding of the wheels on the ground. For this purpose, a pair of right and left intermediate cases are supported by right and left wheel supports of a vehicle body, each to be pivotable about a first steering axis extending substantially vertically. Each intermediate case supports an axle case in a position thereof opposed to the associated dirigible wheel, to be pivotable about a second steering axis extending substantially vertically. The axle case supports the associated dirigible wheel to be rotatable on an axle.

Abstract: A steering apparatus for a working vehicle is provided which is capable of steering dirigible wheels by increased steering angles while checking sideways sliding of the wheels on the ground. For this purpose, a pair of right and left intermediate cases are supported by right and left wheel supports of a vehicle body, each to be pivotable about a first steering axis extending substantially vertically. Each intermediate case supports an axle case in a position thereof opposed to the associated dirigible wheel, to be pivotable about a second steering axis extending substantially vertically. The axle case supports the associated dirigible wheel to be rotatable on an axle.