US3729292A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Anti-friction bearing pad
Assignee: NAW NUTZFAHRZEUGGESELLSCHAFT ARBON & WETZIKON AG ARBON SWITZERLAND A SWITZERLAND CORP
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Filing: 1970-07-02
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Granted: 1973-04-24
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Expires: 1990-07-02
Abstract
Abstract An anti-friction bearing pad which is intended for use, for example, between the leaves of a leaf spring comprises a metal backing disc with a porous layer of sintered bronze or other metal applied to one surface. The porous sintered layer has, at least in its surface part a high proportion of a metal or metals which are more electro-positive than iron and the porous sintered layer is also impregnated with polytetrafluorethylene. The polytetrafluorethylene provides the necessary anti-friction properties and the content of metal which is more electropositive than iron and which is in metal-to-metal contact with the metal of the porous sintered layer acts as a sacrificial anode in preventing corrosion of the spring leaves or other ironcontaining parts with which the surface of the pad is, in use, in contact.
Inventors
- 👤 F Heck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:27
CPC Classifications
F; F16; F16F; F16F1/00; F16F1/02; F16F1/18; F16F1/20; C; C10; C10M; C10M7/00; F16C; F16C33/00; F16C33/02; F16C33/04; F16C33/06; F16C33/12; F16C33/121; F16C33/122; C10M2201/00; C10M2201/04; C10M2201/041; C10M2201/042; C10M2201/05; C10M2201/06; C10M2201/065; C10M2201/066; C10M2201/10; C10M2201/102; C10M2211/00; C10M2211/06; C10M2213/00; C10M2213/02; C10M2213/06; C10M2213/062; C10N; C10N2040/00; C10N2040/02; C10N2050/00; C10N2050/08; C10N2050/10; F16C17/00; F16C17/04; F16C17/12; F16C17/24; F16C2204/00; F16C2204/10; F16C2204/12; F16C2204/50; F16C2240/00; F16C2240/40; F16C2240/60; F16C2300/00; F16C2300/40; F16C2300/42; F16C2326/00; F16C2326/01; F16C2326/05; F16C2361/00; F16C2361/53; F16C33/10; F16C33/1095; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/923; Y10S428/924; Y10S428/926; Y10S428/9265; Y10S428/933; Y10S428/9335; Y10S428/936; Y10S428/938; Y10T; Y10T428/00; Y10T428/12; Y10T428/12007; Y10T428/12014; Y10T428/12028; Y10T428/12063; Y10T428/12069; Y10T428/1209; Y10T428/12229; Y10T428/12236; Y10T428/12243; Y10T428/12264; Y10T428/12389; Y10T428/12451; Y10T428/12493; Y10T428/12771; Y10T428/12785; Y10T428/12792
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
39 words
A pad as claimed in claim 1, wherein said metal which is more electrO-positive than iron is selected from the group consisting of zinc, magnesium and aluminium, said electro-positive metal being in metal-to-metal contact with said porous metal layer.
Claim 2
Dependent Claim
41 words
A pad as claimed in claim 1, further comprising a coating of said metal which is more electro-positive than iron on the surface of said porous layer, said coating having a thickness of from about 30 to about 40 Mu .
Claim 3
Dependent Claim
20 words
A pad as claimed in claim 1, wherein the metal from which said porous layer is made is sintered bronze.
Claim 4
Dependent Claim
20 words
A pad as claimed in claim 1, wherein the metal from which said porous layer is made is sintered iron.
Claim 5
Dependent Claim
17 words
A pad as claimed in claim 1, wherein said porous layer is made from woven metal wire.
Claim 6
Dependent Claim
30 words
A pad as claimed in claim 1, further comprising at least one material selected from the group consisting of graphite, mica, molybdenum sulphide, tin and lead in said porous layer.
Claim 7
Dependent Claim
18 words
A pad as claimed in claim 1, wherein recesses are provided in the surface of said porous layer.
Claim 8
Dependent Claim
27 words
A pad as claimed in claim 8, wherein said recesses define up to about 50 percent of the total area of the surface of said porous layer.
Claim 9
Dependent Claim
34 words
A pad as claimed in claim 8, wherein said recesses are in the form of a series of grooves, grooves in said series extending at right angles to each other to form a grid.
Claim 10
Dependent Claim
21 words
A pad as claimed in claim 1, further comprising a steel support plate to which said porous metal layer is bonded.
Claim 11
Dependent Claim
21 words
A pad as claimed in claim 11, further comprising a coating of said one metal which is more electro-positive than iron.
Claim 12
Dependent Claim
19 words
A pad as claimed in claim 1, wherein the porosity of said porous metal layer is about 25 percent.
Claim 13
Dependent Claim
36 words
A pad as claimed in claim 11, wherein said porous metal layer is a sintered metal having the following composition in parts by weight: copper 84, tin 8, lead 8, graphite 4 and molybdenum sulphide 5.
Claim 14
Dependent Claim
78 words
A process for making an anti-friction bearing pad including the steps of sprinkling a powder mixture onto a steel support plate to form a layer thereon, said powder mixture including bronze, graphite, molybdenum sulphide, tin and lead, sintering said powder mixture to produce a porous layer adhering to said steel support plate, incorporating at least one metal which is more electro-positive than iron in the pores of said porous layer and thereafter impregnating said porous layer with polytetrafluorethylene.
Claim 15
Dependent Claim
29 words
A process as claimed in claim 15, comprising the further step of compressing said sintered powder mixture before said electro-positive metal is incorporated in said porous layer formed thereby.
Claim 16
Dependent Claim
22 words
A process as claimed in claim 16, wherein recesses are formed in the surface of said porous layer during said compressing step.
Claim 17
Dependent Claim
34 words
A process as claimed in claim 15, wherein said step of incorporating said metal which is more electro-positive than iron is carried out by diffusing said at least one metal in said porous layer.
Claim 18
Dependent Claim
28 words
A process as claimed in claim 15, wherein said step of incorporating said metal which is more electro-positive than iron in said porous layer is carried out galvanically.
Claim 19
Dependent Claim
43 words
A process as claimed in claim 15, wherein said step of incorporating said metal which is more electro-positive than iron in said porous layer consists in tumbling said pad with said porous layer thereon in said at least one metal in powdered form.
Claim 20
Dependent Claim
22 words
A process as claimed in claim 15, wherein said porous layer is impregnated with said polytetrafluorethylene in the form of a suspension.
Claim 21
Dependent Claim
21 words
A process as claimed in claim 15, comprising the further step of compressing said porous layer after said impregnation with polytetrafluorethylene.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-23 | 1976-10-23 | 1977-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-23 | 1980-10-23 | 1981-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-23 | 1984-10-23 | 1985-04-24 | $7700.00 | Window Closed / Lapsed |