A compact utility loader compact utility loader comprising a frame, a first track and a second track positioned on either side of the frame, and a pair of loader arms. The loader arms are configured to couple with an attachment via a hitch plate and a hitch pin. The compact utility loader is configured such that as the loader arms are raised and lowered, the hitch pin follows a path approximately defined by a curve f(x)=4.641e.sup.0.34x. The value x represents a horizontal direction and the function f(x) represents a vertical direction.

A controller of a wheeled hydraulic excavator executes control of a vibration suppression function to control the flow of a hydraulic fluid from a hydraulic cylinder that drives a work implement, thereby suppressing vibration of the hydraulic cylinder when the rotation speed of wheels reaches a predetermined speed or higher. Furthermore, the controller disables the control of the vibration suppression function when the vehicle body is jacked up by the work implement, even when a vibration suppression instructing device has given an instruction for enabling the control of the vibration suppression function.

A grapple hydraulic cylinder may comprise a barrel body, a piston-rod assembly, a cap operably connected to the barrel body, and a pressure relief system. The pressure relief system may be operably connected to a rod side chamber and a cap side chamber. The pressure relief system may comprise a first valve and a second valve. The second valve may be a relief valve configured to open upon the cap side chamber reaching a determined pressure and moving hydraulic fluid from the cap side chamber to the rod side chamber while the first valve simultaneously maintains the locked position. Pressure in the cap side chamber is reduced, and pressure in the rod side chamber increases. A similar configuration may be utilized to move hydraulic fluid from the rod side chamber to the cap side chamber to reduce pressure in the rod side chamber.

A grapple hydraulic cylinder may comprise a barrel body, a piston-rod assembly, a cap operably connected to the barrel body, and a pressure relief system. The pressure relief system may be operably connected to a rod side chamber and a cap side chamber. The pressure relief system may comprise a first valve and a second valve. The second valve may be a relief valve configured to open upon the cap side chamber reaching a determined pressure and moving hydraulic fluid from the cap side chamber to the rod side chamber while the first valve simultaneously maintains the locked position. Pressure in the cap side chamber is reduced, and pressure in the rod side chamber increases. A similar configuration may be utilized to move hydraulic fluid from the rod side chamber to the cap side chamber to reduce pressure in the rod side chamber.

A work machine includes a work device having a boom, an arm, and work equipment and a controller that sets a target surface, and calculates a work equipment-to-target surface distance on the basis of signals from a position sensor and a posture sensor, and carries out control to decelerate the arm to keep the work equipment from excavating ground beyond the target surface when the work equipment-target surface distance has become shorter than a predetermined distance. The controller determines whether there is a possibility that the work equipment enters the target surface when operation of the arm is carried out based on the set target surface and the position sensor and posture sensor signals, and does not carry out the deceleration control when the work equipment-to-target surface distance is shorter than the predetermined distance and it is determined there is no possibility that the work equipment enters the target surface.

A system for monitoring a hydraulic cylinder in a work machine is disclosed. The system calculates a normalized seal damage for the hydraulic cylinder based on a normalized wear coefficient. An estimated degradation rate is determined from normalized seal damage calculations performed over a timestep during operation of the work machine, and the estimated degradation rate is compared to a degradation model formed from population hydraulic cylinder data. A service life estimate of a seal of the hydraulic cylinder is identified based on the alignment of the estimated degradation rate within the degradation model.

A hydraulic filter securing device includes an oil pipe including a first thread to engage with a second thread of a hexagonal section of a return filter. An external flange is provided on an outer side surface of the oil pipe between the first end and the second end along a central axis. The external flange has a slot elongated in a circumferential direction with respect to the central axis. The retention bolt includes a shaft and a head. At least part of the shaft has a third thread, and the shaft passes through the slot. The head is provided at a position along the slot such that either the head or the shaft contacts with the hexagonal section when the second thread engages with the first thread. The head is restrained from sliding on the external flange along the slot.

A slew apparatus of a working machine includes a slew frame, an electric motor mounting element mounted to the slew frame and an electric motor mounted to the electric motor mounting element for driving the slew apparatus, the electric motor having a drive axis defining an axial direction and a radial direction normal to the axis, and a drive output shaft, the electric motor mounting element including: a body configured to receive the electric motor; and at least three mounting legs, each leg projecting radially from the body and each leg defining a mounting portion and configured to effect fastening of the electric motor mounting element to the slew frame so as to mount the electric motor to the slew frame, whereby each mounting portion is spaced radially outwardly from the perimeter of the electric motor when viewed in the axial direction thereof.

A compact utility loader compact utility loader comprising a frame, a first track and a second track positioned on either side of the frame, and a pair of loader arms. The loader arms are configured to couple with an attachment via a hitch plate and a hitch pin. The compact utility loader is configured such that as the loader arms are raised and lowered, the hitch pin follows a path approximately defined by a curve (x)=4.641e.sup.0.34x. The value x represents a horizontal direction and the function (x) represents a vertical direction.