Hydraulic cylinder buffer seal backup ring

A seal for a hydraulic cylinder piston rod of a hydraulic cylinder, comprising:

• an annular buffer seal including:
• a first axial pressure side configured to face a rod end chamber of the hydraulic cylinder and fit adjacent a first axial side surface of an annular groove defined in a rod end of the hydraulic cylinder through which the piston rod passes, and
• a second axial seal side opposite from the first axial pressure side, the second axial seal side including a radially outer annular seal surface and a radially inner annular seal surface, wherein the radially outer annular seal surface is spaced farther from the first axial pressure side of the annular buffer seal than the radially inner annular seal surface of the buffer seal such that an annular notch is formed around an inner diameter of the annular buffer seal on the second axial seal side of the annular buffer seal;
• and
• an annular backup ring including:
• a radially extending leg portion extending along and in direct contact with a portion of a radial extent of the radially outer annular seal surface of the annular buffer seal, and
• an axially extending leg portion contiguous with the radially extending leg portion, and extending axially into the annular notch formed around the inner diameter of the annular buffer seal on the second axial seal side of the annular buffer seal,
• wherein the first axial pressure side of the annular buffer seal includes a radially outer annular pressure surface joined to a radially inner annular pressure surface by two contiguous pressure surfaces that together define an annular, concave recess in the first axial pressure side of the buffer seal,
• wherein the radially outer annular pressure surface is configured to contact the first axial side surface of the annular groove,
• wherein the two contiguous and converging tapered pressure surfaces are converging and tapered,
• wherein the annular backup ring covers an entirety of the radial extent of the radially outer annular seal surface of the annular buffer seal,
• wherein the radially extending leg portion of the backup ring terminates in an outer circumferential surface with a radiused chamfer at a radially outer edge of the side of the backup ring facing away from the buffer seal, and
• wherein the annular, concave recess is defined between a radially outer annular leg portion of the buffer seal and a radially inner annular leg portion of the buffer seal, and the radially outer annular leg portion extends farther in an axial direction from the second axial seal side of the buffer seal than the radially inner annular leg portion.