Torque limiter devices, systems and methods and solar trackers incorporating torque limiters

Patent metadata

Field	Value
Publication number	US-2018348331-A1
Application number	US-201816055663-A
Country	US
Kind code	A1
Filing date	Aug 6, 2018
Priority date	Feb 19, 2014
Publication date	Dec 6, 2018
Grant date	—

Abstract

A solar tracker assembly comprises a support column, a torsion beam connected to the support column, a mounting mechanism attached to the torsion beam, a drive system connected to the torsion beam, and a torsion limiter connected to an output of the drive system. When an external force causes a level of torsion on the drive system to exceed a pre-set limit the torsion limiter facilitates rotational movement of the solar tracker assembly in the direction of the torsion, thereby allowing the external force to rotate about a pivot axis extending through the torsion beam. Exemplary embodiments also include methods of aligning a plurality of rows of solar trackers.

First claim

What is claimed is:

1 . A solar tracker assembly comprising:
a support column; a torsion beam connected to the support column; a mounting mechanism attached to the torsion beam; a drive system connected to the torsion beam; and a torsion limiter connected to an output of the drive system; wherein when an external force causes a level of torsion on the drive system to exceed a pre-set limit the torsion limiter facilitates rotational movement of the solar tracker assembly in the direction of the torsion, thereby allowing the external force to rotate about a pivot axis extending through the torsion beam.

2 . The solar tracker assembly of claim 1 wherein the movement in the direction of the torsion de-couples excess torsion such that the external force is released and the level of torsion on the solar tracker assembly is reduced.

3 . The solar tracker assembly of claim 2 wherein the movement in the direction of the torsion comprises movement of the solar tracker assembly from a first rotational position to at least one second rotational position.

4 . The solar tracker assembly of claim 3 wherein the solar tracker assembly hits a maximum position stop in the at least one second rotational position.

5 . The solar tracker assembly of claim 3 wherein the solar tracker assembly is constrained in its maximum rotational positions at multiple distributed locations along a torsional resisting structure of the solar tracker assembly.

6 . The solar tracker assembly of claim 5 wherein the solar tracker assembly includes a plurality of support columns and further comprises a stop at each support column.

7 . The solar tracker assembly of claim 1 wherein the torsion limiter limits a hinge moment about the pivot axis extending through the torsion beam.

8 . The solar tracker assembly of claim 1 wherein the drive system comprises a gear assembly including at least one gear wheel.

9 . The solar tracker assembly of claim 8 wherein the gear assembly includes a one-way gearbox and the torsion limiter is a torsion limiting clutch.

10 . The solar tracker assembly of claim 8 wherein the gear assembly includes a friction coupling engaging the gear wheel and the torsion limiter is located at the friction coupling.

11 . The solar tracker assembly of claim 8 wherein the torsion limiter is located at the output of a first gear stage of the gear assembly.

12 . The solar tracker assembly of claim 1 wherein the solar tracker assembly is a push/pull linked tracker and the torsion limiter is a linear slip device.

13 . The solar tracker assembly of claim 1 wherein the solar tracker assembly includes a hydraulic system and the torsion limiter is a pressure relief valve.

14 . The solar tracker assembly of claim 1 further comprising a damper incorporated at or near the gear rack to control release of torsional force and slow motion of the solar tracker assembly.

15 . The solar tracker assembly of claim 1 wherein the torsion beam is configured with a balanced center of gravity such that it rotates about the balanced center of gravity.

16 . A method of aligning a solar array, comprising:
providing a plurality of rows of solar trackers including multiple rows of linked solar trackers; providing a torsion limiter connected to each row of solar trackers; receiving a level of torsion on at least one row of solar trackers such that the level of torsion on the at least one row of solar trackers exceeds a pre-set torsion limit; using the torsion limiter to stop rotational movement of the at least one row of the multiple rows of solar trackers when the at least one row reaches its maximum limit position; and driving the other multiple rows of solar trackers such that each row reaches its maximum limit position until all of the plurality of rows of solar trackers are aligned.

17 . The method of claim 16 wherein when each row reaches its maximum limit position it stops rotational movement while the other multiple rows of solar trackers rotate and reach their maximum limit positions.

18 . The method of claim 16 wherein each row of solar trackers includes a plurality of support columns and further comprising providing a stop at each support column.

19 . A solar tracker assembly comprising:
a support column; a torsion beam connected to the support column; a mounting mechanism attached to the torsion beam; a drive system connected to the torsion beam, the drive system comprising a bi-directional gearbox having an input and an output; and a motor brake located at the input of the bi-directional gearbox; wherein when an external force causes a level of torsion on the drive system to exceed a pre-set threshold the motor brake slips to facilitate back-driving of the drive system.

Assignees

• Array Tech Inc

Inventors

• Corio Ronald P

Classifications

• F24S40/00

  Safety or protection arrangements of solar heat collectors; Preventing malfunction of solar heat collectors (control arrangements F24S50/00) · CPC title

• F16D43/2024

  the axially moving part being coaxial with the rotation, e.g. a gear with face teeth · CPC title

• F24S2030/136

  for moving several solar collectors by common transmission elements · CPC title

• F24S2030/134

  in the form of gearings or rack-and-pinion transmissions · CPC title

• F24S2030/15

  Bearings · CPC title