Photovoltaic system bearing assembly
A photovoltaic (PV) system having a bearing assembly to support PV modules is described. In an example, the bearing assembly includes a pair of bearing supports having respective sub-rims. The sub-rims may have complementary arcuate seat surfaces, which when combined, define a curved seat rim to receive a bearing sleeve. Accordingly, the bearing supports may be mounted symmetrically about a pile such that the sub-rims combine to support the bearing sleeve, and a torque tube holding the PV modules may be mounted on the bearing sleeve. More particularly, the torque tube may be in sliding contact with the bearing sleeve, and a weight of the PV modules and torque tube may be evenly transmitted through the pair of bearing supports to a shear center of the pile.
1. A photovoltaic (PV) system, comprising:
a pile having a web portion extending along a vertical plane to a pile end;
a pair of bottom bearing supports bilaterally disposed about the web portion, each bottom bearing support including
a shank portion apposed to the web portion,
a fork portion having a lower end coupled to the shank portion and an upper edge having a first fork end and a second fork end above the pile end, and
a sub-rim coupled to the upper edge of the fork portion, wherein the sub-rim includes a bottom seat surface having an arcuate cross-sectional profile revolved around a shaft axis extending orthogonal to the vertical plane, and wherein the bottom seat surfaces of the sub-rims define a bottom seat rim;
a bottom bearing sleeve mounted on the bottom seat rim;
a torque tube mounted on the bottom bearing sleeve, wherein the torque tube extends along the shaft axis and is pivotable about the shaft axis;
a top bearing support having a top seat rim including a top seat surface having an arcuate cross-sectional profile revolved around the shaft axis;
a top bearing sleeve mounted on the top seat rim, wherein the top bearing sleeve and the bottom bearing sleeve include respective supportive surfaces combining to define a circumferential supportive surface around the torque tube;
a plurality of lower fastener tabs, wherein each lower fastener tab extends from one of the fork ends of the pair of bottom bearing supports, wherein the lower fastener tabs include respective friction surfaces parallel to the vertical plane, and respective fastener holes aligned along a first fastener axis extending orthogonal to the vertical plane;
at least two upper fastener tabs coupled to the top seat rim, wherein the at least two upper fastener tabs include friction surfaces parallel to the vertical plane and facing respective friction surfaces of the lower fastener tabs, and respective fastener holes aligned with the respective fastener holes of the lower fastener tabs along the first fastener axis;
a fastener extending through the fastener holes of the upper fastener tabs and the lower fastener tabs to press the friction surfaces together; and
a PV module mounted on the torque tube to track a solar source when the torque tube pivots about the shaft axis.
2. The PV system of claim 1 , wherein the top seat rim and the bottom seat rim have U-shaped cross-sectional profiles.
3. The PV system of claim 1 , wherein at least one of the fastener holes includes a non-circular slot.
4. The PV system of claim 1 , wherein one or more of the bottom bearing supports includes a pair of retention prongs, each retention prong extending radially inward from a respective fastener tab at the fork ends toward the shaft axis, and wherein a distance between each retention prong and the shaft axis is less than a distance between the shaft axis and the bottom seat surface.
5. The PV system of claim 1 , wherein the web portion and the shank portion have respective fastener holes aligned along a fastener axis extending orthogonal to the vertical plane.
6. A system, comprising:
a pile having a web portion extending along a vertical plane to a pile end;
a pair of bottom bearing supports bilaterally disposed about the web portion, each bottom bearing support including
a shank portion apposed to the web portion,
a fork portion having a lower end coupled to the shank portion and an upper edge having a first fork end and a second fork end above the pile end, and
a sub-rim coupled to the upper edge of the fork portion, wherein the sub-rim includes a bottom seat surface having an arcuate cross-sectional profile revolved around a shaft axis extending orthogonal to the vertical plane, and wherein the bottom seat surfaces of the sub-rims define a bottom seat rim;
a bottom bearing sleeve mounted on the bottom seat rim;
a torque tube mounted on the bottom bearing sleeve, wherein the torque tube extends along the shaft axis and is pivotable about the shaft axis;
a top bearing support having a top seat rim including a top seat surface having an arcuate cross-sectional profile revolved around the shaft axis;
a top bearing sleeve mounted on the top seat rim, wherein the top bearing sleeve and the bottom bearing sleeve include respective supportive surfaces combining to define a circumferential supportive surface around the torque tube;
a plurality of lower fastener tabs, wherein each lower fastener tab extends from one of the fork ends of the pair of bottom bearing supports, wherein the lower fastener tabs include respective friction surfaces parallel to the vertical plane, and respective fastener holes aligned along a first fastener axis extending orthogonal to the vertical plane;
at least two upper fastener tabs coupled to the top seat rim, wherein the at least two upper fastener tabs include friction surfaces parallel to the vertical plane and facing respective friction surfaces of the lower fastener tabs, and respective fastener holes aligned with the respective fastener holes of the lower fastener tabs along the first fastener axis; and
a fastener extending through the fastener holes of the upper fastener tabs and the lower fastener tabs to press the friction surfaces together.
7. The system of claim 6 , wherein the top seat rim and the bottom seat rim have U-shaped cross-sectional profiles.
8. The system of claim 6 , wherein at least one of the fastener holes includes a non-circular slot.
9. The system of claim 6 , wherein one or more of the bottom bearing supports includes a pair of retention prongs, each retention prong extending radially inward from a respective fastener tab at the fork ends toward the shaft axis, and wherein a distance between each retention prong and the shaft axis is less than a distance between the shaft axis and the bottom seat surface.
10. The system of claim 6 , wherein the web portion and the shank portion have respective fastener holes aligned along a fastener axis extending orthogonal to the vertical plane.
11. The system of claim 10 , wherein the shank portion and the fork portion include respective inward surfaces facing the vertical plane, and wherein the inward surface of the fork portion is laterally farther from the vertical plane than the inward surface of the shank portion.