Outer pin seal
View Patent ↗A seal ( 200 ) of substantially wedge shaped cross section self adjusts and seals pivot joints ( 100 ) over a range of gap widths to be sealed.
1. A seal for a pivot joint, the pivot joint including a pivot pin and a bushing, the pivot joint rotationally connecting a first member and a second member, the first member having a longitudinal axis and a first external surface substantially conical in shape and substantially symmetrical about a first plane orthogonal to the longitudinal axis, the first external surface having a cross section that is substantially circular on the first plane orthogonal to the longitudinal axis, the second member having a circular external surface that is substantially flat and substantially orthogonal to the longitudinal axis, a gap being defined axially between the first external surface and the circular external surface, the seal comprising:
a first portion forming a circle in a second plane orthogonal to the longitudinal axis, the first portion having a cross sectional shape generally conforming to that of a triangle, an outer diameter of the circle formed by a first corner and a second corner of the triangle, a first lip at the first corner, a second lip at the second corner, an inner diameter of the circle formed by a third corner of the triangle, a first seal surface extending between the third corner and the first corner, a second seal surface extending between the third corner and the second corner, a majority of the first portion of the seal being positioned in the gap;
a second portion along an arc of the circle and positioned along the outer diameter, the second portion having the effect of thickening the seal along the arc, the second portion and the first portion being integral, the first and second portions being split in a plane parallel to the longitudinal axis such that the first portion has a first portion first end and a first portion second end and the second portion has a second portion first end and a second portion second end, a length of the second portion along the arc being greater than a width of the first portion; and
a fastener for connecting the first portion first end and the first portion second end and for connecting the second portion first end and the second portion second end.
2. The seal of claim 1 , wherein the seal is connected over the gap between the first external surface and the circular external surface such that the gap is sealed, the seal fitting around a circumference of the first member external surface.
3. The seal of claim 2 , wherein the first seal surface contacts the first external surface.
4. The seal of claim 3 , wherein the second lip contacts the circular external surface.
5. The seal of claim 4 , wherein the first lip contacts a second external surface of the first member.
6. A method of using a seal to seal a pivot joint, the pivot joint including a pivot pin and a bushing, the pivot joint rotationally connecting a first member and a second member, the first member having a longitudinal axis and a first external surface substantially conical in shape and substantially symmetrical about a first plane orthogonal to the longitudinal axis, the first external surface having a cross section that is substantially circular about the first plane orthogonal to the longitudinal axis, the second member having a circular external surface that is substantially flat and substantially orthogonal to the longitudinal axis, a gap being defined axially between the first external surface and the circular external surface,
the seal including:
a first portion forming a circle in a second plane orthogonal to the longitudinal axis, the first portion having a cross sectional shape generally conforming to that of a triangle, an outer diameter of the circle formed by a first corner and a second corner of the triangle, a first lip at the first corner, a second lip at the second corner, an inner diameter of the circle formed by a third corner of the triangle, a first seal surface extending between the third corner and the first corner, a second seal surface extending between the third corner and the second corner, and
a second portion along an arc of the circle and positioned along the outer diameter, the second portion having the effect of thickening the seal along the arc, a length of the second portion along the arc being greater than a width of the first portion,
the method comprising:
placing the seal of cross-sectional triangular shape across the gap between the first external surface and the circular external surface such that the first external surface contacts the first seal surface and the circular external surface contacts the second corner and such that a majority of the first portion of the seal is positioned in the gap.
7. The method of claim 6 , wherein an outer surface of the seal extends between the first and second corners of the triangle and is substantially parallel to the longitudinal axis.
8. The method of claim 6 , wherein the first member of the pivot joint includes a second external surface adjacent to the first external surface, and an outer surface of the seal is substantially parallel to the second external surface.
9. The seal of claim 1 , wherein an outer surface of the seal extends between the first and second corners of the triangle and is substantially parallel to the longitudinal axis.
10. The seal of claim 1 , wherein the first member of the pivot joint includes a second external surface adjacent the first external surface, and an outer surface of the seal is substantially parallel to the second external surface of the first member.