US20090314387A1 - System and method for controlling interaction between surfaces - Google Patents
System and method for controlling interaction between surfaces Download PDFInfo
- Publication number
- US20090314387A1 US20090314387A1 US12/163,715 US16371508A US2009314387A1 US 20090314387 A1 US20090314387 A1 US 20090314387A1 US 16371508 A US16371508 A US 16371508A US 2009314387 A1 US2009314387 A1 US 2009314387A1
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- United States
- Prior art keywords
- repetitive
- asperities
- unit length
- per unit
- set forth
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- Abandoned
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- 238000000034 method Methods 0.000 title claims abstract description 21
- 230000003993 interaction Effects 0.000 title claims abstract description 14
- 230000003252 repetitive effect Effects 0.000 claims abstract description 21
- 239000002245 particle Substances 0.000 claims abstract description 5
- 239000000463 material Substances 0.000 description 7
- 239000007787 solid Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 239000007788 liquid Substances 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- -1 e.g. Substances 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/24—Structurally defined web or sheet [e.g., overall dimension, etc.]
- Y10T428/24355—Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]
Definitions
- the present invention relates to systems and methods for controlling interaction between surfaces. More specifically, the present invention concerns a system and method for controlling interaction, i.e., interpenetration, between first and second surfaces by arranging or designing the surfaces such that the repetitive surface geometries, or “asperities”, of the surfaces are in particular relative ratios.
- the coefficient of friction is a dimensionless scalar vector describing the ratio of the force of friction between two surfaces and the force bringing them together. A lower coefficient of friction corresponds to less interaction between the surfaces. Coefficients of friction must be measured experimentally as they cannot be calculated.
- Interaction between surfaces is often controlled by selecting materials which result in the desired coefficient of friction. However, in many applications, specific materials must be used, and therefore friction cannot be controlled by using different materials. Interaction between surfaces is also often controlled by interposing a lubricating or abrading substance between the surfaces. However, in some applications these additional substances cannot be used, because, for example, they create an unacceptable risk of contamination, and in other applications the substances do not remain consistently interposed between the surfaces.
- the present invention overcomes the above-described and other problems and disadvantages by providing a system and method for reducing interaction between surfaces moving relative to each other.
- the system broadly comprises a first surface having a first number of repetitive surface asperities per unit length of surface; and a second surface having a second number of repetitive surface asperities per unit length of surface, wherein the first and second numbers are in relative prime ratio, i.e., have no common divisor other than 1, and wherein the first and second surfaces move relative to each other.
- the first number is approximately 11 and the second number is approximately 13.
- the method broadly comprises the steps of providing the first surface with a first number of repetitive surface asperities per unit length of surface; and providing the second surface with a second number of repetitive surface asperities per unit length of surface, wherein the first and second numbers are in relative prime ratio.
- the first number may be approximately 11 and the second number may be approximately 13.
- the ratio of asperities may be controlled as a function of component particle or grain size, groove size, or relative angular orientation of the surfaces.
- FIG. 1 is a cross-sectional elevation view of first and second surfaces arranged or designed in accordance with the present invention to minimize interaction;
- FIG. 2 is a plan view of a first surface under a second surface, wherein the surfaces are oriented at 0 degrees relative to one another;
- FIG. 3 is a plan view of the first surface under the second surface of FIG. 3 , wherein the surfaces are oriented angularly relative to one another.
- the present invention provides a system and method for controlling interaction, i.e., interpenetration, between surfaces, and thereby controlling friction, heat, and abrasive wear between the surfaces.
- the system and method are scale independent, and, as such, have potential applications at, e.g., atomic, molecular, nanomachine, conventional mechanical, and geologic scales.
- potential applications include minimizing friction, heat, and abrasive wear in unlubricated bearings and in lubricated bearings where the lubricant fails to fully and continuously support the load.
- the surfaces 10 , 12 are arranged or designed such that the repetitive surface geometries 14 , 16 , or “asperities”, of the surfaces 10 , 12 are in relative prime ratio. More specifically, the number of asperities 14 of the first surface 10 per unit length of surface is a first number, and the number of asperities 16 of the second surface 12 per unit length of surface is a second number, wherein the first and second numbers are in relative prime ratio.
- “Relative prime ratio” means that the first and second numbers share no common divisors other than 1.
- the first and second numbers may both be prime numbers, such as 7:11 or 17:19, or one of the numbers may be prime and the other number may be any number which has no common divisors with the first number (other than 1), such as 8:11 or 16:19, or neither of the numbers may be prime so long as there are no common divisors between them (other than 1), such as 9:10 or 15:16.
- a relative prime ratio of 11:13 may provide maximum support with minimum interpenetration.
- unit length of surface corresponds to the distance between the 1st and 11th asperities of the first surface 10 (which is equivalent to the distance between the 1st and 13th asperities of the second surface 12 ).
- there is only one point of contact i.e., one point at which an asperity 14 of the first surface 10 aligns with and contacts an asperity 16 of the second surface 12 , over the unit length of surface.
- the 5th and 6th asperities provide intermediate support during the transition between contacting asperities when the surfaces 10 , 14 are moving relative to one another.
- these relative asperity ratios can be controlled as a function of component particle or grain size, while for other scales or materials, e.g., machined materials, these ratios can be controlled as a function of groove size.
- Potential applications for the present invention include reducing friction in or between piston rings and cylinder walls; gears; linear and non-linear bearings and journals; telescoping mechanisms; scroll compressors; engines; and pumps. Furthermore, the present invention may be used in both unlubricated and lubricated applications.
- At least one of the materials presenting the first and second surfaces 10 , 12 may be non-solid.
- the first surface 10 may be a solid, and the second surface 12 may comprise molecules of a liquid or gas such that they behave substantially as a solid surface adjacent to the first surface 10 .
- the first surface 10 may be a chute, and the second surface 12 may comprise grains of sand flowing down the chute.
- the first surface 10 may be a pipe, and the second surface 12 may comprise a liquid or gas under pressure flowing through the pipe.
Abstract
A system and method for reducing interaction between surfaces (10,12) moving relative to each other. The system includes a first surface (10) having a first number of repetitive surface asperities (14), e.g., 11, per unit length of surface, and a second surface (12) having a second number of repetitive surface asperities (16), e.g., 13, per unit length of surface, with the first and second numbers being in relative prime ratio, i.e., having no common divisor other than 1. The ratio of repetitive surface asperities may be controlled as a function of component particle size, grain size; groove size; or relative angular orientation of the surfaces (110,112).
Description
- The present U.S. non-provisional patent application claims priority of a previously filed and co-pending U.S. provisional patent application having the same title, Ser. No. 61/074,310, filed Jun. 20, 2008. The identified previously filed application is hereby incorporated by reference into the present application.
- The present invention relates to systems and methods for controlling interaction between surfaces. More specifically, the present invention concerns a system and method for controlling interaction, i.e., interpenetration, between first and second surfaces by arranging or designing the surfaces such that the repetitive surface geometries, or “asperities”, of the surfaces are in particular relative ratios.
- When interacting surfaces move relative to each other, friction between the surfaces converts kinetic energy to heat and can abrade one or both of the surfaces. In some applications, it is desirable to minimize such interactions.
- The coefficient of friction is a dimensionless scalar vector describing the ratio of the force of friction between two surfaces and the force bringing them together. A lower coefficient of friction corresponds to less interaction between the surfaces. Coefficients of friction must be measured experimentally as they cannot be calculated.
- Interaction between surfaces is often controlled by selecting materials which result in the desired coefficient of friction. However, in many applications, specific materials must be used, and therefore friction cannot be controlled by using different materials. Interaction between surfaces is also often controlled by interposing a lubricating or abrading substance between the surfaces. However, in some applications these additional substances cannot be used, because, for example, they create an unacceptable risk of contamination, and in other applications the substances do not remain consistently interposed between the surfaces.
- The present invention overcomes the above-described and other problems and disadvantages by providing a system and method for reducing interaction between surfaces moving relative to each other.
- In one embodiment, the system broadly comprises a first surface having a first number of repetitive surface asperities per unit length of surface; and a second surface having a second number of repetitive surface asperities per unit length of surface, wherein the first and second numbers are in relative prime ratio, i.e., have no common divisor other than 1, and wherein the first and second surfaces move relative to each other. In one exemplary implementation, the first number is approximately 11 and the second number is approximately 13.
- In one embodiment, the method broadly comprises the steps of providing the first surface with a first number of repetitive surface asperities per unit length of surface; and providing the second surface with a second number of repetitive surface asperities per unit length of surface, wherein the first and second numbers are in relative prime ratio. In one implementations, the first number may be approximately 11 and the second number may be approximately 13. In various implementations, the ratio of asperities may be controlled as a function of component particle or grain size, groove size, or relative angular orientation of the surfaces.
- These and other features of the present invention are described in greater detail below in the section titled DETAILED DESCRIPTION OF THE INVENTION.
- The present invention is described herein with reference to the following drawing figures:
-
FIG. 1 is a cross-sectional elevation view of first and second surfaces arranged or designed in accordance with the present invention to minimize interaction; -
FIG. 2 is a plan view of a first surface under a second surface, wherein the surfaces are oriented at 0 degrees relative to one another; and -
FIG. 3 is a plan view of the first surface under the second surface ofFIG. 3 , wherein the surfaces are oriented angularly relative to one another. - With reference to the drawing figures, a system and method are herein described, shown, and otherwise disclosed in accordance with various embodiments, including a preferred embodiment, of the present invention.
- More specifically, the present invention provides a system and method for controlling interaction, i.e., interpenetration, between surfaces, and thereby controlling friction, heat, and abrasive wear between the surfaces. The system and method are scale independent, and, as such, have potential applications at, e.g., atomic, molecular, nanomachine, conventional mechanical, and geologic scales. For example, potential applications include minimizing friction, heat, and abrasive wear in unlubricated bearings and in lubricated bearings where the lubricant fails to fully and continuously support the load.
- Broadly, referring to
FIG. 1 , when it is desired to reduce interaction between first andsecond surfaces surfaces repetitive surface geometries surfaces asperities 14 of thefirst surface 10 per unit length of surface is a first number, and the number ofasperities 16 of thesecond surface 12 per unit length of surface is a second number, wherein the first and second numbers are in relative prime ratio. - “Relative prime ratio” means that the first and second numbers share no common divisors other than 1. Thus, for example, the first and second numbers may both be prime numbers, such as 7:11 or 17:19, or one of the numbers may be prime and the other number may be any number which has no common divisors with the first number (other than 1), such as 8:11 or 16:19, or neither of the numbers may be prime so long as there are no common divisors between them (other than 1), such as 9:10 or 15:16.
- For certain applications, a relative prime ratio of 11:13 may provide maximum support with minimum interpenetration. In this example, unit length of surface corresponds to the distance between the 1st and 11th asperities of the first surface 10 (which is equivalent to the distance between the 1st and 13th asperities of the second surface 12). As such, there is only one point of contact, i.e., one point at which an
asperity 14 of thefirst surface 10 aligns with and contacts anasperity 16 of thesecond surface 12, over the unit length of surface. Additionally, the 5th and 6th asperities provide intermediate support during the transition between contacting asperities when thesurfaces - For certain scales or materials, e.g., ceramics and metals, these relative asperity ratios can be controlled as a function of component particle or grain size, while for other scales or materials, e.g., machined materials, these ratios can be controlled as a function of groove size.
- Potential applications for the present invention include reducing friction in or between piston rings and cylinder walls; gears; linear and non-linear bearings and journals; telescoping mechanisms; scroll compressors; engines; and pumps. Furthermore, the present invention may be used in both unlubricated and lubricated applications.
- In some applications, at least one of the materials presenting the first and
second surfaces first surface 10 may be a solid, and thesecond surface 12 may comprise molecules of a liquid or gas such that they behave substantially as a solid surface adjacent to thefirst surface 10. In one such application, thefirst surface 10 may be a chute, and thesecond surface 12 may comprise grains of sand flowing down the chute. In another of such applications, thefirst surface 10 may be a pipe, and thesecond surface 12 may comprise a liquid or gas under pressure flowing through the pipe. - Although the present invention has been disclosed with reference to particular embodiments, implementations, versions, and features it is understood that equivalents may be employed and substitutions made herein without departing from the contemplated scope of protection.
- Having thus described the preferred embodiment of the invention, what is claimed as new and desired to be protected by Letters Patent includes the following:
Claims (14)
1. A system comprising:
a first surface having a first number of repetitive surface asperities per unit length of surface; and
a second surface having a second number of repetitive surface asperities per unit length of surface,
wherein the first and second numbers are in relative prime ratio, and
wherein the first and second surfaces move relative to each other.
2. The system as set forth in claim 1 , wherein the first number is approximately 11 and the second number is approximately 13.
3. A system comprising:
a first surface having a first number of repetitive surface asperities per unit length of surface; and
a second surface having a second number of repetitive surface asperities per unit length of surface,
wherein the first and second numbers have no common divisors other than 1, and
wherein the first and second surfaces move relative to each other.
4. The system as set forth in claim 3 , wherein the first number is approximately 11 and the second number is approximately 13.
5. A method of reducing interaction between first and second surfaces, the method comprising the steps of:
providing the first surface with a first number of repetitive surface asperities per unit length of surface; and
providing the second surface with a second number of repetitive surface asperities per unit length of surface,
wherein the first and second numbers are in relative prime ratio.
6. The method as set forth in claim 5 , wherein the first number is approximately 11 and the second number is approximately 13.
7. The method as set forth in claim 5 , wherein the number of repetitive surface asperities is controlled as a function of component particle or grain size.
8. The method as set forth in claim 5 , wherein the number of repetitive surface asperities is controlled as a function of groove size.
9. The method as set forth in claim 5 , wherein the ratio of the first number to the second number is controlled as a function of the angular orientation of the first surface relative to the second surface.
10. A method of reducing interaction between first and second surfaces, the method comprising the steps of:
providing the first surface with a first number of repetitive surface asperities per unit length of surface; and
providing the second surface with a second number of repetitive surface asperities per unit length of surface,
wherein the first and second numbers have no common divisors other than 1.
11. The method as set forth in claim 10 , wherein the first number is approximately 11 and the second number is approximately 13.
12. The method as set forth in claim 10 , wherein the number of repetitive surface asperities is controlled as a function of component particle or grain size.
13. The method as set forth in claim 10 , wherein the number of repetitive surface asperities is controlled as a function of groove size.
14. The method as set forth in claim 10 , wherein the ratio of the first number to the second number is controlled as a function of the angular orientation of the first surface relative to the second surface.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US12/163,715 US20090314387A1 (en) | 2008-06-20 | 2008-06-27 | System and method for controlling interaction between surfaces |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US7431008P | 2008-06-20 | 2008-06-20 | |
US12/163,715 US20090314387A1 (en) | 2008-06-20 | 2008-06-27 | System and method for controlling interaction between surfaces |
Publications (1)
Publication Number | Publication Date |
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US20090314387A1 true US20090314387A1 (en) | 2009-12-24 |
Family
ID=41430028
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/163,715 Abandoned US20090314387A1 (en) | 2008-06-20 | 2008-06-27 | System and method for controlling interaction between surfaces |
US13/000,307 Abandoned US20110170811A1 (en) | 2008-06-20 | 2009-06-19 | System and method for controlling interaction between surfaces |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
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US13/000,307 Abandoned US20110170811A1 (en) | 2008-06-20 | 2009-06-19 | System and method for controlling interaction between surfaces |
Country Status (2)
Country | Link |
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US (2) | US20090314387A1 (en) |
WO (1) | WO2009155552A1 (en) |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2617751A (en) * | 1950-07-10 | 1952-11-11 | Le Roy M Bickett | Rubber pad |
US3525417A (en) * | 1966-11-28 | 1970-08-25 | Isolants Francais Sa | Composite sound insulating boards |
US4351868A (en) * | 1981-04-15 | 1982-09-28 | Toyoda Gosei Co., Ltd. | Molding |
US5060944A (en) * | 1990-10-26 | 1991-10-29 | Spalding & Evenflo Companies, Inc. | Tennis racket with split frame |
US5762631A (en) * | 1995-07-14 | 1998-06-09 | Localmed, Inc. | Method and system for reduced friction introduction of coaxial catheters |
US5860779A (en) * | 1997-11-26 | 1999-01-19 | Mcdonnell Douglas Corporation | Locking nut |
US5947462A (en) * | 1996-10-02 | 1999-09-07 | Jacuzzi, Inc. | Latching mechanism for fluid containment assembly |
US6830793B2 (en) * | 1999-09-27 | 2004-12-14 | The Aerospace Corporation | Composite damping material |
US20050054276A1 (en) * | 2003-09-05 | 2005-03-10 | Boris Shamshidov | Method for reducing wear of mechanically interacting surfaces |
US20070123377A1 (en) * | 2005-11-29 | 2007-05-31 | Roberto Gazzara | Sports racquet with insert members for anchoring strings |
US20080274843A1 (en) * | 2006-10-20 | 2008-11-06 | Prince Sports, Inc. | Method for Manufacturing a Racquet Frame for Sports Racquet and a Racquet Frame Thereof |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CA2463804A1 (en) * | 2003-04-08 | 2004-10-08 | Fort James Corporation | Set of nestable containers, as for waste |
US8758092B2 (en) * | 2005-11-16 | 2014-06-24 | Seagate Technology Llc | Sweeper burnish head |
-
2008
- 2008-06-27 US US12/163,715 patent/US20090314387A1/en not_active Abandoned
-
2009
- 2009-06-19 WO PCT/US2009/048019 patent/WO2009155552A1/en active Application Filing
- 2009-06-19 US US13/000,307 patent/US20110170811A1/en not_active Abandoned
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2617751A (en) * | 1950-07-10 | 1952-11-11 | Le Roy M Bickett | Rubber pad |
US3525417A (en) * | 1966-11-28 | 1970-08-25 | Isolants Francais Sa | Composite sound insulating boards |
US4351868A (en) * | 1981-04-15 | 1982-09-28 | Toyoda Gosei Co., Ltd. | Molding |
US5060944A (en) * | 1990-10-26 | 1991-10-29 | Spalding & Evenflo Companies, Inc. | Tennis racket with split frame |
US5762631A (en) * | 1995-07-14 | 1998-06-09 | Localmed, Inc. | Method and system for reduced friction introduction of coaxial catheters |
US5947462A (en) * | 1996-10-02 | 1999-09-07 | Jacuzzi, Inc. | Latching mechanism for fluid containment assembly |
US5860779A (en) * | 1997-11-26 | 1999-01-19 | Mcdonnell Douglas Corporation | Locking nut |
US6830793B2 (en) * | 1999-09-27 | 2004-12-14 | The Aerospace Corporation | Composite damping material |
US20050054276A1 (en) * | 2003-09-05 | 2005-03-10 | Boris Shamshidov | Method for reducing wear of mechanically interacting surfaces |
US20070123377A1 (en) * | 2005-11-29 | 2007-05-31 | Roberto Gazzara | Sports racquet with insert members for anchoring strings |
US20080274843A1 (en) * | 2006-10-20 | 2008-11-06 | Prince Sports, Inc. | Method for Manufacturing a Racquet Frame for Sports Racquet and a Racquet Frame Thereof |
Also Published As
Publication number | Publication date |
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US20110170811A1 (en) | 2011-07-14 |
WO2009155552A1 (en) | 2009-12-23 |
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Owner name: BABOLAT VS, FRANCE Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:BABOLAT, ERIC;REEL/FRAME:021257/0208 Effective date: 20080610 |
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