Abstract: A hydraulic system includes: a boom cylinder; a working tool cylinder; a boom control valve; a working tool control valve; first and second fluid tubes through which operation fluid is supplied to the boom cylinder; third and fourth fluid tubes through which operation fluid is supplied to the working tool cylinder; a first relief valve provided in a first bypass fluid tube and configured to allow the operation fluid to flow from the fourth fluid tube toward the first fluid tube and to block the operation fluid flowing from the first fluid tube toward the fourth fluid tube; and a second relief valve provided in a second bypass fluid tube and configured to allow the operation fluid to flow from the third fluid tube toward the second fluid tube and to block the operation fluid flowing from the second fluid tube toward the third fluid tube.

Abstract: A hydraulic system includes: a boom cylinder; a working tool cylinder; a boom control valve; a working tool control valve; first and second fluid tubes through which operation fluid is supplied to the boom cylinder; third and fourth fluid tubes through which operation fluid is supplied to the working tool cylinder; a first relief valve provided in a first bypass fluid tube and configured to allow the operation fluid to flow from the fourth fluid tube toward the first fluid tube and to block the operation fluid flowing from the first fluid tube toward the fourth fluid tube; and a second relief valve provided in a second bypass fluid tube and configured to allow the operation fluid to flow from the third fluid tube toward the second fluid tube and to block the operation fluid flowing from the second fluid tube toward the third fluid tube.

Abstract: A front loader includes a mechanical posture maintaining mechanism for maintaining the posture of an implement, regardless of swing displacement of a boom. The boom is formed in a curved shape in which a longitudinal central side thereof is located above. The posture maintaining mechanism includes a swing link member having an inner free-end part and an outer free-end part and disposed at a longitudinal center location of the boom so as to be swingable about a third horizontal pivot as a fulcrum. A base-end link member extends between a fixed bracket and the inner free-end part and a free-end link member links the outer free-end part to the implement.

Abstract: The front loader includes a boom actuator configured to pivotally drive a boom along a vertical direction relative to a traveling vehicle body about a first pivot axis which is oriented along a right/left direction, a bucket actuator configured to pivotally drive a bucket along the vertical direction relative to the boom about a second pivot axis which is oriented along the right/left direction, a manual controlling section for controlling operations of the boom actuator and the bucket actuator based on a manual operation of an operational tool, a boom angle detector for detecting a vertical pivot angle of the boom, a bucket angle detector for detecting a vertical pivot angle of the bucket relative to the boom, a calculating section for calculating a ground pivot angle of the bucket based on an output from the boom angle detector and an output from the bucket angle detector.

Abstract: The front loader includes a boom actuator configured to pivotally drive a boom along a vertical direction relative to a traveling vehicle body about a first pivot axis which is oriented along a right/left direction, a bucket actuator configured to pivotally drive a bucket along the vertical direction relative to the boom about a second pivot axis which is oriented along the right/left direction, a manual controlling section for controlling operations of the boom actuator and the bucket actuator based on a manual operation of an operational tool, a boom angle detector for detecting a vertical pivot angle of the boom, a bucket angle detector for detecting a vertical pivot angle of the bucket relative to the boom, a calculating section for calculating a ground pivot angle of the bucket based on an output from the boom angle detector and an output from the bucket angle detector.

Abstract: A front loader is provided with an indicator device. The indicator device is configured to indicate that the work implement is in an identical posture irrespective of a height position of the work implement, by aligning a rear end of the indicator rod with a rear end of the guide tube.

Abstract: A front loader includes a mechanical posture maintaining mechanism for maintaining the posture of an implement, regardless of swing displacement of a boom. The boom is formed in a curved shape in which a longitudinal central side thereof is located above. The posture maintaining mechanism includes a swing link member having an inner free-end part and an outer free-end part and disposed at a longitudinal center location of the boom so as to be swingable about a third horizontal pivot as a fulcrum. A base-end link member extends between a fixed bracket and the inner free-end part and a free-end link member links the outer free-end part to the implement.

Abstract: A loading work apparatus includes booms, attachment tools, an implement tool removably attached to the attachment tools, and implement tool cylinders. The implement tool includes an engaged member on a back surface thereof. The attachment tools include an attachment unit having an engaging member engaged with the engaged member, coupling members supporting the transverse shaft, and lock members locking/unlocking engagement between the engaging member and engaged member. Each coupling member includes brackets on lateral opposite sides of the lock member. The transverse shaft is supported at opposite ends thereof by lower portions of the right and left brackets. The support shaft is supported at opposite ends thereof by intermediate portions of the right and left brackets. The transverse shaft and the support shaft bridge across the lock member.

Abstract: A detection link of a spill guard link mechanism is pivoted and connected to a bucket bracket in a position proximate to a bucket pivot support axis rotatably supporting a bucket and above a lower surface of a boom.

Abstract: A front loader 3 is connected to a front portion of a tractor 1 having a tractor body. The front loader 3 includes mounting frames 7 arranged at right and left sides of the tractor body, booms 8 pivotally supported by upper ends of the mounting frames 7 to be vertically swingable, and a working implement 9 swingably connected to distal ends of the booms 8. A control valve 45 is disposed outside the tractor body 2 and rearwardly of one of the mounting frames 7 for controlling hydraulic cylinders 17, 29.

Abstract: Disclosed is a front loader provided with an indicator device. The indicator device is configured to indicate that the work implement is in an identical posture irrespective of a height position of the work implement, by aligning a rear end of the indicator rod with a rear end of the guide tube.

Abstract: A loading work apparatus includes booms, attachment tools, an implement tool removably attached to the attachment tools, and implement tool cylinders. The implement tool includes an engaged member on a back surface thereof. The attachment tools include an attachment unit having an engaging member engaged with the engaged member, coupling members supporting the transverse shaft, and lock members locking/unlocking engagement between the engaging member and engaged member. Each coupling member includes brackets on lateral opposite sides of the lock member. The transverse shaft is supported at opposite ends thereof by lower portions of the right and left brackets. The support shaft is supported at opposite ends thereof by intermediate portions of the right and left brackets. The transverse shaft and the support shaft bridge across the lock member.

Abstract: A front loader 3 is connected to a front portion of a tractor 1 having a tractor body. The front loader 3 includes mounting frames 7 arranged at right and left sides of the tractor body, booms 8 pivotally supported by upper ends of the mounting frames 7 to be vertically swingable, and a working implement 9 swingably connected to distal ends of the booms 8. A control valve 45 is disposed outside the tractor body 2 and rearwardly of one of the mounting frames 7 for controlling hydraulic cylinders 17, 29.

Abstract: A detection link of a spill guard link mechanism is pivoted and connected to a bucket bracket in a position proximate to a bucket pivot support axis rotatably supporting a bucket and above a lower surface of a boom.

Abstract: The invention provides a loader work machine with improved front visibility and improved aesthetic appearance. The loader work machine includes a self-propelled machine body, a work device having a boom, a boom cylinder, and a side frame for vertically pivotally supporting base portions of the boom and the boom cylinder, and a frame unit for attaching the work device to the self-propelled machine body. The frame unit has a support platform projecting laterally outward from the self-propelled machine body and a main frame mounted erect on the support platform for supporting and connecting a lower portion of the side frame. An accumulator is connected to the boom cylinder for absorbing shock occurring during a vertical pivotal movement of the work device and this accumulator is attached to the frame unit.

Abstract: There is provided a boom assembly bent at the center in a longitudinal direction so as to form a round shape protruding upward when seen from the side, comprising; a front boom sub assembly (47), the front boom sub assembly constituting the front of the center in the longitudinal direction of said boom assembly; and a rear boom sub assembly (48), the rear boom sub assembly constituting the rear of the center in the longitudinal direction of the boom assembly, wherein the front boom sub assembly (47) and the rear boom sub assembly (48) are symmetric when seen from the side, and portions from the midway positions in the longitudinal direction of the front boom sub assembly (47) and the rear boom sub assembly (48) to the center in the longitudinal direction of the boom assembly (12) have upper surfaces of arc shape protruding upward when seen from the side, and portions from the middles in the longitudinal direction of the front boom sub assembly (47) and the rear boom sub assembly (48) to ends in the longitudin

Abstract: A loader control device for controlling a loader implement attached to a tractor is disposed in a position adjacent a driver's seat and does not obstruct the driver boarding or alighting from the tractor. For this purpose, the tractor includes a vehicle body; a loader implement detachably attached to a front part of the vehicle body; a driver's seat mounted on the vehicle body; a steering device disposed forwardly of the driver's seat; a step laid between the driver's seat and the steering device; rear wheel fenders at opposite lateral positions of the driver's seat; and a shifting unit disposed between the driver's seat and one of the rear wheel fenders; wherein a mounting unit for mounting a loader control device for controlling the loader implement is provided in a forward position of an upper surface of the one of the rear wheel fenders.

Abstract: A loader work machine including a vehicle body, and a working implement having booms and boom cylinders and mounting frame units for attaching the working implement to a front portion of the vehicle body. Each of the mounting frame units includes a mounting plate fixed to the vehicle body, a support base projecting laterally outward from the mounting plate, a main frame erected on the support base, and a side frame for pivotally supporting proximal ends of one of the booms and one of the boom cylinders. The side frame includes right and left side plates and a connecting element for interconnecting the right and left side plates. The side frame is detachably attached to the main frame by engaging an engaging member disposed in a lower portion of the side frame with an engageable member of the main frame, and connecting a connecting member formed on the side frame to a connectable member formed on the main frame. The main frame is formed as a one-piece plate insertable between the right and left side plates.

Abstract: A front loader 3 is connected to a front portion of a tractor 1 having a tractor body. The front loader 3 includes mounting frames 7 arranged at right and left sides of the tractor body, booms 8 pivotally supported by upper ends of the mounting frames 7 to be vertically swingable, and a working implement 9 swingably connected to distal ends of the booms 8. A control valve 45 is disposed outside the tractor body 2 and rearwardly of one of the mounting frames 7 for controlling hydraulic cylinders 17, 29.