US3976342A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for reducing fretting wear between relatively moving parts
Assignee: Robert Bosch GmbH
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Filing: 1975-05-20
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Granted: 1976-08-24
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Expires: 1995-05-20
Abstract
Abstract Machine parts subject to relative vibration motion, in particular a metal spindle fitting with some play in the socket of another member as in the case of an ignition distributor arm joint, are provided, on at least one of the relatively moving surfaces, with closely spaced cavities in which wear products may accumulate, leaving a web-like engagement surface. The cavities do not permit displacement of materials in the direction of vibration, which has the advantage, if the engagement is greased, of holding the grease in the engagement area. Instead of providing the cavities by pits or grooves on one or both of the relatively vibrating surfaces, a perforated or woven and rolled insert of metal or tough synthetic material may be used.
Inventors
- 👤 Ralf Leyendecker
- 👤 Gunter Heinke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:38
CPC Classifications
F; F16; F16C; F16C33/00; F16C33/02; F16C33/04; F16C33/06; F16C33/10; F16C33/102; F16C17/00; F16C17/12; F16C17/24
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
135 words
The method of improving the friction and wear properties of two surfaces moving against each other with vibratory slip motion, at least one of which surfaces is metallic, which comprises interrupting the continuity of frictional surface engagement by the provision in the friction zone of a multiplicity of individual cavities each of a mouth area of at least 0.02 mm 2 in such number as to be close to each other and to leave a network of narrow strips to form thereby a web-like bearing surface, whereby the products of wear are taken up by said cavities, said cavities being substantially empty and being provided in such a manner that they have openings facing at least one of said moving surfaces which is free to move in vibratory motion across said opening of said cavities.
Claim 2
Independent Claim
135 words
The method of improving the friction and wear properties of two surfaces moving against each other with vibratory slip motion, at least one of which surfaces is metallic, which comprises interrupting the continuity of frictional surface engagement by the provision in the friction zone of a multiplicity of individual cavities each of a mouth area of at least 0.02 mm 2 in such number as to be close to each other and to leave a network of narrow strips to form thereby a web-like bearing surface, whereby the products of wear are taken up by said cavities, said cavities being substantially empty and being provided in such a manner that they have openings facing at least one of said moving surfaces which is free to move in vibratory motion across said opening of said cavities.
Claim 3
Dependent Claim
39 words
A method as defined in claim 1 in which, in the region of said cavities, the ratio of bearing surface area A b to the aggregate mouth area of said cavities is between the limits of 0.05 and 6.0.
Claim 4
Dependent Claim
21 words
A method as defined in claim 2 in which said ratio A b / A c lies between 0.1 and 1.0.
Claim 5
Dependent Claim
46 words
A method as defined in claim 2 in which said cavities are provided in said friction zone by the provision of a perforated separator sheet between said relatively moving surfaces containing said cavities and providing a web-like bearing surface to each of said relatively moving surfaces.
Claim 6
Dependent Claim
30 words
A method as defined in claim 4 in which said perforated separator sheet consists of a material selected from the group consisting of metal, synthetic resin material and self-lubricating materials.
Claim 7
Dependent Claim
21 words
A method as defined in claim 4 in which said perforated separator sheet has a thickness between 0.02 and 2 mm.
Claim 8
Dependent Claim
42 words
A method as defined in claim 6 in which said perforated separator sheet has circular holes, such that the smallest distance between two neighboring hole edges lies between 0.1 and 2.0 mm and the hole diameter is between 0.2 and 10 mm.
Claim 9
Dependent Claim
46 words
A method as defined in claim 6 in which said perforated separator sheet has noncircular holes, such that the distance between edges of adjacent holes lies between 0.1 and 2.0 mm and the area of the individual holes lies between 0.02 and 100 mm 2 .
Claim 10
Dependent Claim
34 words
A method as defined in claim 2 in which said cavities are provided by the insertion between said relatively moving surfaces of a separator sheet with a pitted surface on at least one side.
Claim 11
Dependent Claim
58 words
A method as defined in claim 9 in which said interposed separator sheet has pitted surfaces on both sides and provides a web-like bearing surface to each of said relatively moving surfaces, the pits of the two sides of said separator piece being interlocked, with a pit on one side generally corresponding to a web on the other.
Claim 12
Dependent Claim
18 words
A method as defined in claim 10 in which said separator sheet is of metal or synthetic material.
Claim 13
Dependent Claim
74 words
A method as defined in claim 11 in which said separator sheet has a thickness between 0.05 and 5 mm, the distance between the edge of adjacent pits on the same surface is between 0.1 and 2 mm the cross sectional area of individual pits at the mouth thereof is between 0.02 and 100 mm 2 and the depth of said pits is between 5 and 90% of the thickness of said separator sheet.
Claim 14
Dependent Claim
40 words
A method as defined in claim 2 in which said cavities are provided by the provision between said relatively moving surfaces of a wire or synthetic fiber fabric sheet, which prior to insertion has been flatened by rolling or pressing.
Claim 15
Dependent Claim
52 words
A method as defined in claim 13 in which the mesh width of said fabric is between 0.02 and 10 mm and the wire or fiber thickness between0.01 and 1.5 mm and in which the fabric thickness is reduced by not less than 5% of its original thickness by rolling or pressing.
Claim 16
Dependent Claim
53 words
A method as defined in claim 2 in which at least one of said relatively moving surfaces is provided with fine pits or grooves by the successive steps of roughening the profile of the surface and then superficially smoothing the surface to provide a smoothness of web-like bearing surface within a required tolerance.
Claim 17
Dependent Claim
158 words
A rotary force transmitting coupling comprising a spindle end and a member having a socket loosely mating said spindle end with a clearance space between the spindle periphery and the walls of said socket sufficient to provide play in the relative position of said spindle and said socket and thereby to allow vibratory relative slip movement between said spindle end and said socket in response to vibratory forces, said spindle being mounted for rotary motion about a longitudinal axis thereof and at least one of said spindle and the socket portion of said member being made of metal, wherein the improvement is provided that: frictional engagement of said spindle end and said socket is limited to a network of narrow strip areas by the provision of a multiplicity of substantially empty cavities in the surface of one of said spindle end and said socket, and said cavities have a minimum mouth cross-sectional area of 0.02 mm 2 .
Claim 18
Dependent Claim
158 words
A rotary force transmitting coupling comprising a spindle end and a member having a socket loosely mating said spindle end with a clearance space between the spindle periphery and the walls of said socket sufficient to provide play in the relative position of said spindle and said socket and thereby to allow vibratory relative slip movement between said spindle end and said socket in response to vibratory forces, said spindle being mounted for rotary motion about a longitudinal axis thereof and at least one of said spindle and the socket portion of said member being made of metal, wherein the improvement is provided that: frictional engagement of said spindle end and said socket is limited to a network of narrow strip areas by the provision of a multiplicity of substantially empty cavities in the surface of one of said spindle end and said socket, and said cavities have a minimum mouth cross-sectional area of 0.02 mm 2 .
Claim 19
Dependent Claim
176 words
A rotary force transmitting coupling comprising a spindle end and a member having a cup-shaped hollow socket loosely mating said spindle end with a clearance space between the spindle periphery and the walls of said socket sufficient to provide play in the relative position of said spindle and said socket and thereby to allow vibratory relative slip movement between said spindle end and said socket in response to vibratory forces, said spindle being mounted for rotary motion about a longitudinal axis thereof, at least one of said spindle and the socket portion of said member being made of metal, wherein the improvement is provided that: a thin insert is provided between said spindle end and the socket portion of said member separating them and consisting of a sheet of firm tough material having substantially empty cavities opening to at least one side of said sheet, said sheet being equally free to slip relative to the said parts on both sides of it, and said cavities have a minimum mouth cross-sectional area of 0.02 mm 2 .
Claim 20
Dependent Claim
176 words
A rotary force transmitting coupling comprising a spindle end and a member having a cup-shaped hollow socket loosely mating said spindle end with a clearance space between the spindle periphery and the walls of said socket sufficient to provide play in the relative position of said spindle and said socket and thereby to allow vibratory relative slip movement between said spindle end and said socket in response to vibratory forces, said spindle being mounted for rotary motion about a longitudinal axis thereof, at least one of said spindle and the socket portion of said member being made of metal, wherein the improvement is provided that: a thin insert is provided between said spindle end and the socket portion of said member separating them and consisting of a sheet of firm tough material having substantially empty cavities opening to at least one side of said sheet, said sheet being equally free to slip relative to the said parts on both sides of it, and said cavities have a minimum mouth cross-sectional area of 0.02 mm 2 .
Claim 21
Dependent Claim
19 words
A rotary force transmitting coupling as defined in claim 17 in which said cylindrical sleeve is made of metal.
Claim 22
Dependent Claim
22 words
A rotary force transmitting coupling as defined in claim 18 in which said sleeve is made of a pressure flattened wire fabric.
Claim 23
Dependent Claim
19 words
A rotary force transmitting coupling as defined in claim 18 in which said sleeve is made of perforated metal.
Claim 24
Dependent Claim
44 words
A rotary force transmitting coupling as defined in claim 18 in which said sleeve is made of a thin metal sheet pitted on both sides in an interlocking pattern in which a pit on one side is backed by a web on the other.
Claim 25
Dependent Claim
25 words
A rotary force transmitting coupling as defined in claim 17 in which said cavities are provided at least in part by perforations in said insert.
Claim 26
Dependent Claim
58 words
A rotary force transmitting coupling as defined in claim 17 in which said cavities are provided on both sides of said insert in the form of pits, said pits being provided in an interlocking pattern in which pits on one side of said insert are backed by a web between pits on the other side of said insert.
Claim 27
Dependent Claim
26 words
A rotary force transmitting coupling as defined in claim 17 in which said insert is a pressure flattened fabric of filaments of a firm tough material.
References Cited (Backward Citations)
US2905511A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-24 | 1980-02-23 | 1980-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-24 | 1984-02-23 | 1984-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-24 | 1988-02-23 | 1988-08-24 | $7700.00 | Window Closed / Lapsed |