TORSIONAL DAMPING DEVICE
20170227080 · 2017-08-10
Inventors
Cpc classification
International classification
Abstract
A torsional damping device and methods are disclosed. The device has an inertial body, a housing, a biasing mechanism, and a damping element. The housing has a mounting surface for mounting to a structure experiencing a rotational force, the inertial body rotatably and removably coupled to the housing. The biasing mechanism is configured to bias the inertial body towards the neutral position. The damping element is configured to damp motion of the inertial body relative to the housing. The second position of the inertial body comprises a position wherein the inertial body is at least one of (a) in motion relative to the housing and (b) experiencing a net rotational force from at least one of (a) the biasing mechanism and (b) the damping element. The inertial body is configured to effectuate a counter-rotational force on the structure when the inertial body is in the second position.
Claims
1. A torsional damping device, comprising a first inertial body having a rotational axis and a moment of inertia relative to the rotational axis, the first inertial body rotatable about the rotational axis between a neutral position and a second position; a housing configured to house the inertial body, the housing having a mounting surface for mounting to a structure experiencing a rotational force, the first inertial body rotatably and removably coupled to the housing; a biasing mechanism configured to bias the first inertial body towards the neutral position; a damping element configured to damp motion of the first inertial body relative to the housing; wherein the neutral position of the first inertial body comprises a position wherein the first inertial body is not in motion relative to the housing and is not experiencing a net rotational force; the second position of the first inertial body comprises a position wherein the first inertial body is experiencing a net rotational force from at least one of (a) the biasing mechanism and (b) the damping element; and the first inertial body is configured to effectuate a counter-rotational force on the structure when the first inertial body is in the second position.
2. The torsional damping device of claim 1, wherein the structure is a solar panel system having a resonant frequency; and the torsional damping device is configured to damp motion of the structure at the resonant frequency.
3. The torsional damping device of claim 1, wherein the first inertial body is removable from the housing; and the housing is configured to house a second inertial body having a moment of inertia that is different from the moment of inertia of the first inertial body.
4. The torsional damping device of claim 1, further comprising: the torsional damping device is configured to receive at least one of a replacement inertial body and a replacement damping element, whereby the torsional damping device is adjustable to damp motion of a structure having a resonant frequency.
5. The torsional damping device of claim 1, wherein the biasing mechanism comprises a spring.
6. The torsional damping device of claim 1, wherein the damping element comprises a viscous fluid.
7. The torsional damping device of claim 6, wherein the housing further comprises: a port configured to enable an operator to at least one of (a) introduce the viscous fluid into the housing and (b) remove the viscous fluid from the housing.
8. The torsional damping device of claim 1, wherein the damping element comprises a brake.
9. The torsional damping device of claim 1, wherein the mounting structure comprises a passage through at least a portion of the housing and the first inertial body whereby the torsional damping device is mountable on a shaft.
10. The torsional damping device of claim 9, wherein the housing comprises a first housing portion and a second housing portion, the first housing portion detachably coupled to the second housing portion, the housing configured to fit around the shaft; and the first inertial body comprises a first body portion and a second body portion, the first body portion detachably coupled to the second body portion, the first inertial body configured to fit around the shaft.
11. The torsional damping device of claim 1, wherein the housing comprises a longitudinal axle; and the first inertial body comprises a cylindrical outer circumference and a bearing for mounting to the axle.
12. The torsional damping device of claim 1, wherein the mounting surface comprises a flange for attaching the torsional damping device to an end of a shaft.
13. The torsional damping device of claim 1, wherein the housing further comprises: a detachable cover configured to enable an operator to access an interior region of the housing without damaging the torsional damping device.
14. A method of damping wind effects on a solar panel system, the method comprising: providing a torsional damping device, the torsional damping device having: a first inertial body having a rotational axis and a moment of inertia relative to the rotational axis, the first inertial body rotatable about the rotational axis between a neutral position and a second position; a housing configured to house the inertial body, the housing having a removable cover and a mounting surface for mounting to a structure experiencing a rotational force, the first inertial body rotatably and removably coupled to the housing; a biasing mechanism configured to bias the first inertial body towards the neutral position; a first damping element configured to damp motion of the first inertial body relative to the housing; wherein the neutral position of the first inertial body comprises a position wherein the first inertial body is not in motion relative to the housing and is not experiencing a net rotational force; the second position of the first inertial body comprises a position wherein the first inertial body is experiencing a net rotational force from at least one of (a) the biasing mechanism and (b) the first damping element; and the first inertial body is configured to effectuate a counter-rotational force on the structure when the first inertial body is in the second position; affixing the torsional damping device to a mounting shaft of the solar panel system; subjecting the solar panel system to wind tending to cause the solar panel system to oscillate; and allowing the first inertial body to rotate relative to the housing.
15. The method of claim 14, further comprising: introducing the first damping element to the housing by filling the housing with a first viscous fluid.
16. The method of claim 14, wherein: the solar panel system has a resonant frequency; and the method comprises damping motion of the solar panel system at the resonant frequency.
17. The method of claim 16, further comprising: selecting the first inertial body to be configured to damp motion of the solar panel system at the resonant frequency.
18. The method of claim 14, further comprising: replacing the first inertial body with a second inertial body having a moment of inertia that is different from the moment of inertia of the first inertial body.
19. The method of claim 14, further comprising: adjusting the torsional damping device to damp motion of the solar panel system having a first resonant frequency or a second resonant frequency different from the first resonant frequency; wherein adjusting comprises at least one of (a) replacing the first inertial body with a second inertial body having a moment of inertia that is different from the moment of inertial of the first inertial body and (b) replacing the first damping element with a second damping element, the second damping element having a coefficient of resistance that is different from a coefficient of resistance of the first damping element.
20. The method of claim 19, further comprising providing a torsional damping device comprising a first viscous fluid; and wherein adjusting comprises replacing the first viscous fluid with a second viscous fluid having a viscosity that is different from a viscosity of the first viscous fluid.
21. The method of claim 14, further comprising: sliding the torsional damping device onto a shaft in the solar panel system; clamping the torsional damping device onto a shaft in the solar panel system; or fastening the torsional damping device onto an end of a shaft in the solar panel system.
22. The method of claim 14, further comprising: accessing an interior region of the housing after affixing the torsional damping device to the mounting shaft.
23. A method of retrofitting a solar panel system, the method comprising: providing a torsional damping device, the torsional damping device having: a first inertial body having a rotational axis and a moment of inertia relative to the rotational axis, the first inertial body rotatable about the rotational axis between a neutral position and a second position; a housing configured to house the inertial body, the housing having a mounting surface for mounting to a structure experiencing a rotational force, the first inertial body rotatably and removably coupled to the housing; a biasing mechanism configured to bias the first inertial body towards the neutral position; a damping element configured to damp motion of the first inertial body relative to the housing; wherein the neutral position of the first inertial body comprises a position wherein the first inertial body is not in motion relative to the housing and is not experiencing a net rotational force; the second position of the first inertial body comprises a position wherein the first inertial body is experiencing a net rotational force from at least one of (a) the biasing mechanism and (b) the damping element; and the first inertial body is configured to effectuate a counter-rotational force on the structure when the first inertial body is in the second position; and affixing the torsional damping device to a mounting shaft of the solar panel system.
24. The method of claim 23, wherein: the solar panel system has a resonant frequency; and the method comprises selecting the first inertial body to be configured to damp motion of the solar panel system at the resonant frequency.
25. The method of claim 23, further comprising: replacing the first inertial body with a second inertial body having a moment of inertia that is different from the moment of inertia of the first inertial body.
26. The method of claim 23, further comprising: adjusting the torsional damping device to damp motion of the solar panel system having a first resonant frequency or a second resonant frequency different from the first resonant frequency; wherein adjusting comprises at least one of (a) replacing the first inertial body with a second inertial body having a moment of inertia that is different from the moment of inertial of the first inertial body and (b) replacing a first viscous fluid with a second viscous fluid, the second viscous fluid having a viscosity that is different from a viscosity of the first viscous fluid.
27. The method of claim 23, further comprising: sliding the torsional damping device onto a shaft in the solar panel system; clamping the torsional damping device onto a shaft in the solar panel system; or fastening the torsional damping device onto an end of a shaft in the solar panel system.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
[0030] Before providing a detailed description of various embodiments described herein, it is noted that all absolute terms, particularly those describing relative features such as “round”, “horizontal”, etc., are to be understood as meaning within a reasonable manufacturing or industry tolerance. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments. Claims reciting “at least one of A and B” shall be construed to recite “A and/or B”. Likewise, where the description recites “A and/or B”, support should be found for claim language reciting “at least one of A and B.”
[0031] Turning now to
[0032] In some embodiments, the device has a detachable cover 206. As illustrated in
[0033] Although not illustrated, those skilled in the art will understand that the detachable cover 206 may be detachable using any means now known or as yet to be developed, including, without limitation, a hinge mechanism, a cam mechanism, and/or a screw mechanism. In some embodiments, the cover is not detachable, and instead may be unitary with the body 232.
[0034] Returning to
[0035] Continuing with
[0036] When the device 200 is mounted to a structure such as a horizontal shaft 104 in a solar panel system 100, torsional motion of the solar panel system 100 will tend to cause the inertial body 202 to rotate relative to the housing 204. The biasing mechanism 210 may be selected so as to bias the inertial body 202 towards a first position that is fixed relative to the housing 204. That is, the biasing mechanism 210 may bias the inertial body 202 towards a particular degree of rotation wherein the inertial body 202 does not experience a net rotational force in either direction relative to the housing 204. Relatedly, the viscous fluid 208 may be selected so as to bias the inertial body 202 towards a position that is fixed relative to the housing 204. That is, the viscous fluid 208 may tend to bias the inertial body 202 to come to a stop if the inertial body 202 is rotating relative to the housing 204.
[0037] Together, the inertial body 202, the viscous fluid 208, and the biasing mechanism 210 may be configured to dampen motion of a structure such as a solar panel system 100 that is moving, such as galloping at or near a resonant frequency of the solar panel system. In some embodiments, the inertial body 202 and the biasing mechanism 210 may be selected to create a natural frequency of rotational vibration that matches or nearly matches a rotational vibration frequency of the solar panel system 100.
[0038] In some embodiments, the torsional damping device 200 is configured to be field-installable and/or adjustable.
[0039] For example, a detachable cover 206 may allow an operator to transport the device 200 in an unassembled state, and then assemble the device 200 to a shaft 104 in the field. A port 230 in the housing 204, such as the cover 206 and/or the body 232, may allow an operator to fill the housing 204 with the viscous fluid 208 before or after assembly to the shaft 104.
[0040] In some embodiments, the device 200 is adjustable. In some adjustable embodiments, the housing 204 may be configured or sized to accept different sizes or styles of inertial bodies 202 and/or biasing mechanisms 210. The operator may, for example, wish to remove a first inertial body 202 having a first moment of inertia and replace it with a second inertial body 202 having a moment of inertia that is different from the first inertial body 202. This adjustability may be particularly suitable where the solar panel system 100 is, for example, upgraded to hold a differently sized solar panel 102 or other structure, which would affect the resonant frequency of the solar panel system 100 and hence demand a change in the device 200 to account for the changed resonant frequency. In some embodiments, a mass of the inertial body 202 is selected based on the mass distribution of the solar panel system 100 and the degree of damping desired. In some embodiments, the biasing mechanism 210 is selected or configured to match or nearly match the natural frequency of the torsional mode to be damped.
[0041] In some adjustable embodiments, device 200 is configured such that an operator may remove and replace a first viscous fluid 208 with a first viscosity with a second viscous fluid 208 with a second viscosity that is different from the first viscosity.
[0042] Those skilled in the art will understand that, although a viscous fluid 208 is primarily described in this document, any damping element tending to bias the inertial body 202 towards a resting position may be implemented. For example, a brake, braking interface, viscous damping device, restraint, or other mechanical, electrical, or magnetic blocking or retarding device between the inertial body 202 and the housing 204 may be provided. In some embodiments, one or more ball bearings or a ball bearing interface may be placed between the inertial body 202 and the housing 204. In some embodiments, the ball bearings may be configured to provide a resistance force to damp rotation of the inertial body 202 via friction or any suitable manner of resistance.
[0043] Continuing with
[0044] In some embodiments, and as illustrated in
[0045] Turning now to
[0046] In some embodiments, the passage 750 need not extend through the entirety of the device 700. For example, the device 200, 700 may include a recess (not illustrated) that only extends into a portion of the first end 224 or second end 228 of the device 200, 700 such as, for example through a portion of the housing 704, to facilitate attachment to the shaft 104. The recess may include other means for assisting in affixing the device 200, 700 to the shaft 104, such as, for example, cams, hinges, locks, screws, etc.
[0047] The embodiments described in the preceding two paragraphs may facilitate the ease of assembling or affixing the device 200, 700 to an end 110 of a shaft 104 that is already installed in the field without dismantling the solar panel system 100.
[0048] Turning now to
[0049] Likewise, the inertial body 902 may have a first inertial body portion 902a and a second inertial body portion 902b; the cover 906, where provided, may also have a first cover portion 906a and a second cover portion 906b. The biasing mechanism 910 may include a torsional spring that is wound about the shaft 104 in the field, or may include a plurality of torsional spring portions that are coupled together. Taken together, the device 900 may have a first portion 900a and a second portion 900b that fit about the shaft 104. If a viscous fluid 208 is used, the portions 900a, 900b should be provided with a seal to prevent leakage.
[0050] Turning now to
[0051] A damping element 1209 may be provided to effectuate a net rotational force F on the inertial body 1202. The damping element 1209 may be a combination of a viscous fluid 208 and a spring or biasing element or mechanism, such as the spring 210 illustrated in
[0052] As illustrated in
[0053] Turning now to
[0054] Turning now to
[0055] By combining resistance forces and biasing forces in this manner, the device 200 may be configured to effectuate a counter-rotational force on the solar panel assembly 100 or structure to which the device 200 is attached when the first inertial body 202, 1202 is in the second position B, C. Put succinctly, in some embodiments, the device 200 may be configured to damp motion of a solar panel system 100 experiencing winds tending to cause the system 100 to oscillate at a resonant frequency of the solar panel system 100. The device 200 may damp motion of the system 100 by changing the resonant frequency of the system 100 to one that does not respond to the particular winds being applied to the solar panel system 100, or by applying counter-rotational forces on the solar panel system 100, such as wherein the counter-rotational forces are intentionally not tuned to the resonant frequency of the system. In some embodiments, the device 200 is configured to excite the solar panel system 100 at a frequency that is different from the resonant frequency of the solar panel system 100.
[0056] In some embodiments, the device 200 is configured to effectuate a rotational force or torque that counters the rotational inertia of the system 100. For example, the countering rotational force may have a phase and may be configured to be 90 degrees out of phase with a phase of the primary structure, thereby reducing net forces on the primary structure. The greatest countering forces may occur when the rotational speed of the secondary mass, relative to the primary mass, is maximized Depending on the phase, this may occur when the primary mass reaches maximum deflection.
[0057] Turning now to
[0058] Turning now to
[0059] The method 1400 includes providing 1402 a torsional damping device, affixing 1404 the device to a shaft of the structure or solar panel system, subjecting 1406 the structure or solar panel system to wind tending to cause the solar panel system to oscillate, and allowing 1408 the device to damp motion of the structure or solar panel system, such as by allowing the first inertial body to rotate relative to the housing. In some embodiments, the method 1400 includes damping motion of a solar panel system experiencing winds tending to cause the system to oscillate at a resonant frequency of the solar panel system.
[0060] The method 1400 may also include filling 1410 the housing with a first viscous fluid.
[0061] The method 1400 may also include selecting a first inertial body to be configured to damp motion of the solar panel system at the resonant frequency and/or replacing a first inertial body with a second inertial body having a moment of inertia that is different from the moment of inertia of the first inertial body.
[0062] The method 1400 may also include adjusting 1412 the torsional damping device. Adjusting 1412 may include at least one of (a) replacing a first inertial body with a second inertial body having a moment of inertia that is different from the moment of inertial of the first inertial body and (b) replacing a first viscous fluid with a second viscous fluid, the second viscous fluid having a viscosity that is different from a viscosity of the first viscous fluid.
[0063] The method 1400 may also include sliding the torsional damping device onto a shaft in the solar panel system, clamping the torsional damping device onto a shaft in the solar panel system, and/or fastening the torsional damping device onto an end of a shaft in the solar panel system.
[0064] The method 1400 may also include accessing an interior region of the housing after affixing the torsional damping device to the mounting shaft.
[0065] With reference now to
[0066] In some embodiments, the method 1400 may include measuring the motion of the solar panel using motion sensors, such as accelerometers, to determine natural frequencies and mode shapes. In some embodiments, the method 1400 includes calculating an expected natural frequency based on the design parameters of the solar panel system. In some embodiments, the method 1400 includes adjusting or tuning the device to match the natural frequency of interest.
[0067] The method 1500 may also include filling 1506 the housing with a first viscous fluid.
[0068] The method 1500 may also include selecting a first inertial body to be configured to damp motion of the solar panel system at the resonant frequency and/or replacing a first inertial body with a second inertial body having a moment of inertia that is different from the moment of inertia of the first inertial body.
[0069] The method 1500 may also include adjusting the torsional damping device. Adjusting may include at least one of (a) replacing a first inertial body with a second inertial body having a moment of inertia that is different from the moment of inertial of the first inertial body and (b) replacing a first viscous fluid with a second viscous fluid, the second viscous fluid having a viscosity that is different from a viscosity of the first viscous fluid.
[0070] The method 1500 may also include sliding the torsional damping device onto a shaft in the solar panel system, clamping the torsional damping device onto a shaft in the solar panel system, and/or fastening the torsional damping device onto an end of a shaft in the solar panel system.
[0071] The method 1500 may also include accessing an interior region of the housing after affixing the torsional damping device to the mounting shaft.
[0072] The method 1500 may have all steps described with reference to method 1400 and vice versa. Likewise, either method 1400, 1500 may be achieved using the devices 200, 500, 700, 900, 1100 previously described herein.
[0073] The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
[0074] Each of the various elements disclosed herein may be achieved in a variety of manners. This disclosure should be understood to encompass each such variation, be it a variation of an embodiment of any apparatus embodiment, a method or process embodiment, or even merely a variation of any element of these. Particularly, it should be understood that the words for each element may be expressed by equivalent apparatus terms or method terms—even if only the function or result is the same. Such equivalent, broader, or even more generic terms should be considered to be encompassed in the description of each element or action. Such terms can be substituted where desired to make explicit the implicitly broad coverage to which this invention is entitled.
[0075] As but one example, it should be understood that all action may be expressed as a means for taking that action or as an element which causes that action. Similarly, each physical element disclosed should be understood to encompass a disclosure of the action which that physical element facilitates. Regarding this last aspect, by way of example only, the disclosure of a “fastener” should be understood to encompass disclosure of the act of “fastening” —whether explicitly discussed or not—and, conversely, were there only disclosure of the act of “fastening”, such a disclosure should be understood to encompass disclosure of a “fastening mechanism”. Such changes and alternative terms are to be understood to be explicitly included in the description.
[0076] The previous description of the disclosed embodiments and examples is provided to enable any person skilled in the art to make or use the present invention as defined by the claims. Thus, the present invention is not intended to be limited to the examples disclosed herein. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention as claimed.