An end fitting for a sucker rod, the end fitting comprising: a body having an interior, a closed end, an open end, and a wedge system formed in the interior, wherein the wedge system comprises: an outer wedge portion formed in the interior proximate to the open end, wherein the outer wedge portion comprises a first leading edge, a first trailing edge, and a first angle between the first leading edge and the first trailing edge, wherein the first leading edge faces the open end and the first trailing edge faces the closed end, and wherein the length of the first leading edge, the length of the first trailing edge, and the size of the first angle define a first distribution of force in the outer wedge portion; an intermediate wedge portion formed in the interior between the outer wedge portion and the closed end, wherein the intermediate wedge portion comprises a second leading edge, a second trailing edge, and a second angle between the second leading edge and the second trailing edge, wherein the second leading edge faces the open end and the second trailing edge faces the closed end, and wherein the length of the second leading edge, the length of the second trailing edge, and the size of the second angle define a second distribution of force in the intermediate wedge portion; and an inner wedge portion formed in the interior between the intermediate wedge portion and the closed end, proximate to the closed end, wherein the inner wedge portion comprises a third leading edge, a third trailing edge, and a third angle first angle between the third leading edge and the third trailing edge, wherein the third leading edge faces the open end and the third trailing edge faces the closed end, and wherein the length of the third leading edge, the length of the third trailing edge, and the size of the third angle define a third distribution of force in the inner wedge portion, wherein the first trailing edge, the second trailing edge, and the third trailing edge differ in length such that during use a compressive load applied to the sucker rod at the inner wedge portion is greater than a compressive load applied to the sucker rod at the intermediate wedge portion, and the compressive load applied to the sucker rod at the intermediate wedge portion is greater than a compressive load applied to the sucker rod at the outer wedge portion, such that compressive forces applied to the sucker rod at the closed end of the body exceed compressive forces at the open end of the body. view more

The end fitting of claim 7, wherein the first trailing edge is longer than the second trailing edge, and wherein the second trailing edge is longer than the third trailing edge.

An end fitting for a sucker rod, the end fitting comprising: a body having an interior, a closed end, an open end, and a wedge system formed in the interior, wherein the wedge system comprises: an outer wedge portion formed in the interior proximate to the open end, wherein the outer wedge portion comprises a first leading edge, a first trailing edge, and a first angle between the first leading edge and the first trailing edge, wherein the first leading edge faces the open end and the first trailing edge faces the closed end, and wherein the length of the first leading edge, the length of the first trailing edge, and the size of the first angle define a first distribution of force in the outer wedge portion; an intermediate wedge portion formed in the interior between the outer wedge portion and the closed end, wherein the intermediate wedge portion comprises a second leading edge, a second trailing edge, and a second angle between the second leading edge and the second trailing edge, wherein the second leading edge faces the open end and the second trailing edge faces the closed end, and wherein the length of the second leading edge, the length of the second trailing edge, and the size of the second angle define a second distribution of force in the intermediate wedge portion; and an inner wedge portion formed in the interior between the intermediate wedge portion and the closed end, proximate to the closed end, wherein the inner wedge portion comprises a third leading edge, a third trailing edge, and a third angle first angle between the third leading edge and the second third edge, wherein the third leading edge faces the open end and the third trailing edge faces the closed end, and wherein the length of the third leading edge, the length of the third trailing edge, and the size of the third angle define a third distribution of force in the inner wedge portion, wherein the length of at least two of the first trailing edge, the second trailing edge, and the third trailing edge vary, and wherein the first distribution of force, the second distribution of force, and the third distribution of force vary such that during use a compressive load applied to the sucker rod at the inner wedge portion is greater than a compressive load applied to the sucker rod at the intermediate wedge portion, and the compressive load applied to the sucker rod at the intermediate wedge portion is greater than a compressive load applied to the sucker rod at the outer wedge portion, such that compressive forces applied to the sucker rod at the closed end of the body exceed compressive forces at the open end of the body. view more

The end fitting of claim 21, wherein the first leading edge is longer than the second leading edge, and wherein the second leading edge is longer than the third leading edge.

The end fitting of claim 21, wherein the first trailing edge is longer than the second trailing edge, and wherein the second trailing edge is longer than the third trailing edge.

An end fitting for a sucker rod comprising: an exterior surface, a closed end, an open end, and an interior surface, wherein the interior surface comprises a wedge system defining a cavity, wherein the wedge system comprises three wedge shaped portions each having a leading edge nearest the open end and a trailing edge nearest the closed end, wherein the leading edge is longer than the trailing edge, wherein the three wedge shaped portions comprise a first wedge shaped portion proximate the closed end, a second wedge shaped portion proximate the first wedge shaped portion, and a third wedge shaped portion proximate the open end, wherein the leading edge is shortest in the first wedge portion and increases progressively from the closed end to the open end thereby compensating for the compression of the sucker rod in the end fitting, and wherein the first wedge shaped portion receives compressive forces that are greater than the compressive forces which the second wedge shaped portion receives, and the second wedge shaped portion receives compressive forces that are greater than the compressive forces which the third wedge shaped portion receives, such that the compressive forces create a force differential along the wedge system greater at the closed end of the fitting and decreasing toward the open end of the fitting, and wherein the angle between the leading edge and the trailing edge of each concaved surface is obtuse. view more

The end fitting of claim 32, wherein the wedge system creates different compressive forces on each respective wedge shaped portion thereof with the compressive force being inversely proportional to a length of each leading edge.

The end fitting of claim 32, further comprising a fiber composite rod having an end engaged centrally within the end fitting.

A sucker rod comprising: a fiber composite rod having a first end and a second end; and end fittings on each end of the fiber composite rod for coupling together a plurality of fiber composite rods, at least one of the end fittings comprising: an exterior surface, a closed end, an open end, and an interior surface, wherein the interior surface comprises a wedge system defining a cavity, wherein the wedge system comprises a first wedge shaped portion having an arcuate apogee, a perigee, a first leading edge, a first trailing edge, and a first wedge length, wherein the first leading edge is longer than the first trailing edge, and wherein the first leading edge faces the open end and the first trailing edge faces the closed end; a second wedge shaped portion between the first wedge shaped portion and a third wedge shaped portion, wherein the second wedge shaped portion comprises a second leading edge, a second trailing edge, and a second wedge length, wherein the second leading edge is longer than the second trailing edge, and wherein the second leading edge faces the open end and the second trailing edge faces the closed end; and a third wedge shaped portion between the second wedge shaped portion and the open end, wherein the third wedge shaped portion comprises a third leading edge, a third trailing edge, and a third wedge length, wherein the third leading edge is longer than the third trailing edge, and wherein the third leading edge faces the open end and the third trailing edge faces the closed end, wherein the first leading edge is shorter than the second leading edge and the second leading edge is shorter than the third leading edge, thereby compensating for the compression of the sucker rod in the end fitting, wherein the first trailing edge is shorter than the second trailing edge and the second trailing edge is shorter than the third trailing edge, thereby compensating for the back pressure associated with the sucker rod in the end fitting, wherein the ratio of the first trailing edge to the first leading edge of the first wedge shaped portion is larger than the ratio of the second trailing edge to the second leading edge of the second wedge shaped portion, and the ratio of the second trailing edge to the second leading edge of the second wedge shaped portion is larger than the ratio of the third trailing edge to the third leading edge of the third wedge shaped portion, and wherein the second wedge length is greater than the first wedge length and the third wedge length is greater than the second wedge length, such that a force differential along the wedge system is created having compressive forces greater at the closed end of the fitting and decreasing toward the open end of the fitting. view more