A cushion mechanism for decelerating a piston rod includes a holder fastened to an end surface of a cylinder portion fitted with an inner peripheral surface of a cylinder tube, a plurality of fastening bolts for fastening the holder to the cylinder portion, an annular entry portion provided on the piston rod and advancing into the holder and the cylinder portion in the vicinity of the stroke end, a cushion passage formed by penetrating at least one of the plurality of fastening bolts and allowing a working chamber and a discharge port to communicate with each other and leading a working fluid in the working chamber to a discharge port, and an orifice portion provided on the cushion passage and applying resistance to a flow of the working fluid.

A fluid pressure cylinder which has a head cover and a rod cover provided on both ends of a cylinder tube, wherein the head cover and the rod cover are formed by casting such as die-casting. A first connecting channel which recesses in a groove shape in the outward radial direction is formed in the outer-circumferential surface of a first concave section of the head cover. A ring-shaped first holder is pressed into the first concave section, causing the formation of a cross-sectionally rectangular first connecting channel, the opening region of which is sealed. In addition, the first connecting channel connects a cylinder chamber of the cylinder tube and a first cushion chamber of the head cover.

A steering system for an articulated truck. The articulated truck is formed of a tractor and a trailer and an articulation joint. The steering system includes a hydraulic cylinder, with a cylinder barrel and a piston. The steering system provides for changes in angle between the tractor and the trailer. The hydraulic cylinder includes a snubbing tube projecting into the cylinder barrel. A hydraulic fluid passage opens into the cylinder barrel within the snubbing tube. The snubbing tube includes a main slot and a plurality of channels each extending between an interior and an exterior of the snubbing tube. The plurality of channels have a cross sectional area smaller than a cross sectional area of the main slot. When the articulated truck is steered, the piston moves in the cylinder barrel and the snubbing tube dampens the movement to prevent forces generated by the piston damaging the articulated truck.

The vibration damper including a hydraulic end stop that has a sealing ring which is arranged between the end stop ring and the closure element, is supported axially on one side at the end stop ring, engages radially around the piston rod, is mounted in a sliding manner at the piston rod, and with its outer circumferential surface radially contacts the inner wall of the control space, wherein the sealing ring has at least one radial throttle groove which takes effect when the end stop with the sealing ring moves into the control space and ensures a defined flow of damping medium between the control chamber and the first working space, and wherein the sealing ring has a plurality of spring tongues which are supported at a supporting surface on the piston rod side.

A cushion mechanism for decelerating a piston rod includes a holder fastened to an end surface of a cylinder portion fitted with an inner peripheral surface of a cylinder tube, an annular entry portion provided on the piston rod and advancing into the holder and the cylinder portion in the vicinity of the stroke end, a cushion passage leading a working fluid of the working chamber to a supply/discharge port, and an orifice plug fastened to the cushion passage, and the cushion passage includes an internal passage extending in a radial direction of the holder and to which the orifice plug is fastened, and the orifice plug is replaceable through a replacement port formed by penetrating the cylinder tube and communicating with the internal passage.

One or more components of a high pressure pump include a hydraulic surge dampener. The hydraulic surge dampener mitigates or prevents damage that results from a sudden pressure surge that results from impact of components, for example a hydraulic piston and a hydraulic head, of the high pressure pump. The hydraulic surge dampener may include one or more grooves, one or more through holes, or a combination thereof. The hydraulic surge dampener may be carried by or be part of one or more components of the high pressure pump, such as the hydraulic piston, the hydraulic head, or both.

A hydraulic cylinder may have a tube extending from a tube first end to a tube second end, and a piston in the tube. The hydraulic cylinder may also have a piston rod attached to the piston and a cushion stem extending from the piston. The hydraulic cylinder may have a head end cavity disposed adjacent to the tube first end. The hydraulic cylinder may have a cushion sleeve disposed on the cushion stem. The cushion sleeve may be received in the head end cavity. The cushion sleeve may have an inner sleeve including an opening that receives the cushion stem. Further, the cushion sleeve may have a circumferential projection extending from an outer surface of the inner sleeve. The cushion sleeve may also have an outer sleeve surrounding the inner sleeve. An inner surface of the outer sleeve may have a circumferential recess that receives the circumferential projection.

A hydraulic actuator (200) for a work machine (100) includes a rod member (206) defining an annular shoulder (208), a piston (230) coupled to the rod member (206), and a collar (500) engaging with the rod member (206) and the piston (230). The collar (500) includes a body (502) defining a first end (504) and a second end (506). The body (502) includes a cylindrical portion (508) extending from the first end (504) of the body (502) towards the second end (506) of the body (502) and defining a first inner diameter (D1). The cylindrical portion (508) extends along a longitudinal axis (A1) of the hydraulic actuator (200). The body (502) also includes a flange (510) disposed at the second end (506) of the body (502) and radially extending from the cylindrical portion (508). The flange (510) defines a second inner diameter (D2). The first inner diameter (D1) of the cylindrical portion (508) is greater than the second inner diameter (D2) of the flange (510). The flange (510) is axially disposed between the piston (230) and the annular shoulder (208) defined by the rod member (206).

The disclosure herein relates to a single acting hydraulic cylinder (100) configured to provide a smooth extension stroke of a piston (102). The cylinder (100) includes a piston rod (108) connected to the piston (102), wherein the piston rod (108) has a plurality of orifices (110) defined at pre-determined positions, and the piston (102) has a groove (106) defined in fluid communication with the orifices (110) and a fluid gallery (104) defined in the piston (102). The orifices allow fluid to flow from an annular side chamber (124) to a full-bore side chamber (125) via the fluid gallery at end of extension stroke, to gradually dampen impact of the piston (102) with a cylinder head end cover (130). The cylinder prevents jolts and jerks in a hydraulic system, provides better control, and ease in operation.

In a fluid pressure cylinder, a joint portion is formed to have a larger thickness in a radial direction than a main body portion and a connecting portion, an inclination angle of the connecting portion relative to the main body portion is formed so as to be smaller than an inclination angle of a boundary portion between the main body portion and the connecting portion and an inclination angle of a boundary portion between the connecting portion and the joint portion, and the thickness of the connecting portion in the radial direction at an end portion on the joint portion side is formed so as to be larger than the thickness of the main body portion and equal to or smaller than twice the thickness of the main body portion.