Abstract: A hydraulic system of a work machine includes a first hydraulic actuator, a first control valve, a first oil passage, a second hydraulic actuator, a second control valve, a second oil passage, and a bypass oil passage. The first control valve is connected to the first hydraulic actuator to control the first hydraulic actuator. The first oil passage is connected to the first control valve to supply hydraulic oil to the first control valve. The second control valve connected to the second hydraulic actuator to control the second hydraulic actuator. The second oil passage connects the second control valve and the first hydraulic actuator via the first control valve. Hydraulic oil returning from the first hydraulic actuator to the first control valve is to be supplied to the second control valve through the second oil passage. The bypass oil passage connects the first oil passage and the second oil passage.

Abstract: A hydraulic system of a work machine includes a first hydraulic device to operate in a first operation mode while pressure of hydraulic oil supplied from a hydraulic pump via a first oil passage is equal to or higher than a first pressure threshold. The hydraulic oil in the first oil passage is to be discharged via a second oil passage. A pilot check valve is provided in the second oil passage and has a pilot port to receive a pilot pressure of the hydraulic oil. The pilot check valve is closed to stop discharging the hydraulic oil in the first oil passage through the second oil passage while the pilot pressure is higher than or equal to the second pressure threshold. The pilot check valve is opened while the pilot pressure is less than the second pressure threshold.

Abstract: A work machine includes a machine body, a motor provided in a rear portion of the machine body, a bonnet which covers a rear of the motor and which is openable, a tank disposed between the motor and the bonnet, and a support member. The support member includes a bracket supporting the tank on the bonnet such that the tank is separated from the bonnet.

Abstract: A hydraulic system for a work machine includes a hydraulic pump to supply a pilot fluid, and a hydraulic switch valve to be switched to a plurality of switching positions based on a pilot pressure. The pilot pressure is a pressure of the pilot fluid supplied from the hydraulic pump. The hydraulic system includes a direction switch valve to apply a first pilot pressure to the hydraulic switch valve to switch the hydraulic switch valve into one of the plurality of switching positions. The hydraulic system includes a pressure applying device to apply a second pilot pressure to the hydraulic switch valve. The second pilot pressure is lower than the first pilot pressure.

Abstract: A hydraulic system of a work machine includes a first oil path which is connected to a hydraulic pump and though which hydraulic oil is to flow from the hydraulic pump. An operation valve is connected to the first oil path. An operation lever is to control the operation valve to control pressure of the hydraulic oil in accordance with an operation of the operation member. A hydraulic instrument is to be actuated by the hydraulic oil output from the operation valve. A second oil path connects the operation valve and the hydraulic instrument. The hydraulic oil in the second oil path is discharged through a discharge oil path. An actuation valve is provided in the discharge oil path. An actuation valve controller is to control the actuation valve to be opened and closed according to a temperature of hydraulic oil detected by a first sensor.

Abstract: The present invention intends to allow a good layout of and an easy maintenance of parts disposed around a rear portion of the motor. A working machine includes a machine body; a motor mounted on the machine body; an output shaft protruding from a rear portion of the motor; a rear attachment portion disposed on the rear portion of the motor, the rear attachment portion facing backward; and a mount member configured to support the motor to suppress vibration of the motor, the mount member including: a first support member having an opposite attachment portion, the opposite attachment portion being attached opposite to the rear attachment portion; an elastic member attached to the first support member; and a second support member disposed on the machine body, the second support member being configured to support the elastic member.

Abstract: A working machine includes a travel device, a motive power transmission device configured to transmit a motive power to the travel device, a transmission case configured to house the motive power transmission device, and a hydraulic operation fluid tank disposed on an upper surface of the transmission case.

Abstract: The present invention intends to allow a good layout of and an easy maintenance of parts disposed around a rear portion of the motor. A working machine includes a machine body; a motor mounted on the machine body; an output shaft protruding from a rear portion of the motor; a rear attachment portion disposed on the rear portion of the motor, the rear attachment portion facing backward; and a mount member configured to support the motor to suppress vibration of the motor, the mount member including: a first support member having an opposite attachment portion, the opposite attachment portion being attached opposite to the rear attachment portion; an elastic member attached to the first support member; and a second support member disposed on the machine body, the second support member being configured to support the elastic member.

Abstract: The present invention intends to provide a working machine capable of improving the heat exchange efficiency of the radiator and of suppressing degradation of performance of the radiator even when the oil cooler is clogged up, in the working machine arranging the radiator and the oil cooler above the engine. A working machine includes: a motor; a fan arranged above the motor, the fan being configured to generate an air flow downward; a radiator arranged above the fan; and an oil cooler arranged adjacent to the radiator. In addition, the working machine includes: a shroud disposed around fan, the shroud including: a rim portion forming an air vent hole, the air vent hole being for passage of the air flow generated by the fan; and a support member attached to an upper portion of the shroud, the support member being configured to support the radiator and the oil cooler.

Abstract: A loader work machine is disclosed in which a base portion of each of right/left arms (77) is received by an arm support portion (164) of a first lift link (81) and pivotally supported by a first arm shaft (88), and a hydraulic pipe arrangement (167) connected to a hydraulic actuator (98) extend through an support frame (11) from inside to outside of its inner wall (12), and toward an arm (77). The base portion of the arm (77) is supported to the arm support portion (164) at a position adjacent a link outer wall (157) in a transverse direction so that a hose accommodation space (165) is formed between a link inner wall (156) and an internal side face of the base portion of the arm (77). The hydraulic pipe arrangement (167) runs frontward of the first arm shaft (88) and a first link shaft (85), and is disposed in the hose accommodation space (165).

Abstract: Positional relationship among the first link support shaft (85), the second link support shaft (86), the first arm support shaft (88) and the second arm support shaft (89) is set such that an upper portion of the first lift link (81) comes into substantial agreement with a rear end of the machine body (1), when the upper free end of the first lift link (81) is pivoted maximally rearward in the course of transition of the arm (77) from a lowermost state realized lifting down the arm (77) to an uppermost state realized by lifting up the arm (77).

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 hood for a loader work machine 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. The transverse connecting member includes a front wall plate and an upper wall plate projecting rearward from an upper end of the front wall plate. The upper wall plate of the transverse connecting member is disposed more downwardly than the vertical center of the cabin. A rear portion of the upper wall plate is inclined downwardly rearward. A hood upper wall is provided for covering a rear upper side between the pair of right/left support frame members. A front end portion of the hood upper wall is connected to the rear portion of the upper wall plate of the transverse connecting member. The hood upper wall is inclined downwardly rearward in correspondence with the rear portion of the upper wall plate.

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 loader work machine is disclosed in which a base portion of each of right/left arms (77) is received by an arm support portion (164) of a first lift link (81) and pivotally supported by a first arm shaft (88), and a hydraulic pipe arrangement (167) connected to a hydraulic actuator (98) extend through an support frame (11) from inside to outside of its inner wall (12), and toward an arm (77). The base portion of the arm (77) is supported to the arm support portion (164) at a position adjacent a link outer wall (157) in a transverse direction so that a hose accommodation space (165) is formed between a link inner wall (156) and an internal side face of the base portion of the arm (77). The hydraulic pipe arrangement (167) runs frontward of the first arm shaft (88) and a first link shaft (85), and is disposed in the hose accommodation space (165).