US4244994A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laminated aramid fiber friction members
Assignee: Raymark Industries Inc
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Filing: 1979-06-21
•
Granted: 1981-01-13
•
Expires: 1999-06-21
Abstract
Abstract A laminated friction member, such as a clutch facing comprising a friction element comprising aramid fibers and a reinforcing element formed of non-aramid fibers, the elements being impregnated with and bonded together by means of heat-curable cement.
Inventors
- 👤 James T. Trainor
- 👤 Stanley F. Covaleski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:54
CPC Classifications
B; B32; B32B; B32B5/00; B32B5/22; B32B5/24; B32B5/26; D; D04; D04H; D04H3/00; D04H3/02; B32B5/02; B32B5/024; F; F16; F16D; F16D69/00; F16D69/02; F16D69/025; F16D69/026; B32B2260/00; B32B2260/02; B32B2260/021; B32B2260/04; B32B2260/044; B32B2262/00; B32B2262/02; B32B2262/0261; B32B2262/0269; B32B2305/00; B32B2305/72; B32B2475/00; F16D13/00; F16D13/58; F16D13/60; Y; Y10; Y10S; Y10S428/00; Y10S428/902; Y10T; Y10T428/00; Y10T428/21; Y10T428/213; Y10T428/24; Y10T428/24273; Y10T428/24322; Y10T428/24331; Y10T442/00; Y10T442/60; Y10T442/659; Y10T442/668
Claims Analysis
Total Claims: 58
Claim 1
Independent Claim
115 words
A friction member comprising a friction element formed of aramid fibers having a decomposition temperature of at least 850° F. impregnated with a heat-curable cement and disposed in a configuration to form a first preform, and a reinforcing element comprising non-aramid fibers impregnated with a heat-curable cement and disposed in a configuration to form a second preform, said cement with which said non-aramid fibers are impregnated being compatible with that with which said aramid fibers are impregnated, said first and second preforms having been superimposed one upon the other and subjected to heat and pressure to compress said preforms, to cure said cement and to bond said preforms together to form a unitary friction member.
Claim 2
Dependent Claim
115 words
A friction member comprising a friction element formed of aramid fibers having a decomposition temperature of at least 850° F. impregnated with a heat-curable cement and disposed in a configuration to form a first preform, and a reinforcing element comprising non-aramid fibers impregnated with a heat-curable cement and disposed in a configuration to form a second preform, said cement with which said non-aramid fibers are impregnated being compatible with that with which said aramid fibers are impregnated, said first and second preforms having been superimposed one upon the other and subjected to heat and pressure to compress said preforms, to cure said cement and to bond said preforms together to form a unitary friction member.
Claim 3
Dependent Claim
16 words
A friction member according to claim 1 in which said aramid fibers are substantially continuous filaments.
Claim 4
Dependent Claim
15 words
A friction facing according to claim 1 in which said aramid fibers are staple fibers.
Claim 5
Dependent Claim
23 words
A friction member according to claim 1 in which said first preform contains up to about 30 percent, by weight, of non-aramid fibers.
Claim 6
Dependent Claim
49 words
A friction member according to claim 1 in which the cement with which the fibers of said first and second preforms are impregnated comprises from about 20 to about 80 percent, by weight, of a thermosetting resin and from about 80 to about 20 percent of a heat-curable elastomer.
Claim 7
Dependent Claim
38 words
A friction member according to claim 5 in which said thermosetting resin is a phenol formaldehyde resin, said heat-curable elastomer is a natural rubber, and said resin and elastomer are present in substantially equal quantities in said cement.
Claim 8
Dependent Claim
22 words
A friction member according to claim 1 in which said aramid fibers have a decomposition temperature of at least about 900° F.
Claim 9
Dependent Claim
32 words
A friction member according to claim 1 in which said aramid fibers are formed of the condensation product of terephthalic acid and p-phenylenediamine, and have a decomposition temperature of about 930° F.
Claim 10
Dependent Claim
45 words
A friction member according to claim 1 having molded therein a plurality of holes extending from the exposed surface of said friction element into said reinforcing element, the exposed surface of said reinforcing element having been removed to a depth sufficient to expose said holes.
Claim 11
Dependent Claim
15 words
A friction member according to claim 1 in the form of a disc brake pad.
Claim 12
Dependent Claim
14 words
A friction member according to claim 1 in the form of a brake lining.
Claim 13
Dependent Claim
118 words
An annular friction facing comprising a friction element comprising aramid fibers having a decomposition temperature of at least 850° F. impregnated with a heat-curable cement and disposed so as to form a first annular preform, and a reinforcing element formed of non-aramid fibers impregnated with a heat-curable cement and disposed so as to form a second annular preform, said cement with which said non-aramid fibers are impregnated being compatible with that with which said tape of aramid fibers is impregnated, said first and second preforms having been superimposed one upon the other and subjected to heat and pressure to compress said preforms and to cure said cement to bond said preforms together to form an annular friction facing.
Claim 14
Dependent Claim
118 words
An annular friction facing comprising a friction element comprising aramid fibers having a decomposition temperature of at least 850° F. impregnated with a heat-curable cement and disposed so as to form a first annular preform, and a reinforcing element formed of non-aramid fibers impregnated with a heat-curable cement and disposed so as to form a second annular preform, said cement with which said non-aramid fibers are impregnated being compatible with that with which said tape of aramid fibers is impregnated, said first and second preforms having been superimposed one upon the other and subjected to heat and pressure to compress said preforms and to cure said cement to bond said preforms together to form an annular friction facing.
Claim 15
Dependent Claim
24 words
A friction facing according to claim 12 in which said aramid fibers are in the form of a tape comprising a plurality of yarns.
Claim 16
Dependent Claim
20 words
A friction facing according to claim 12 in which said aramid fibers are in the form of a knitted tape.
Claim 17
Dependent Claim
16 words
A friction facing according to claim 13 in which said aramid fibers are substantially continuous filaments.
Claim 18
Dependent Claim
15 words
A friction facing according to claim 13 in which said aramid fibers are staple fibers.
Claim 19
Dependent Claim
49 words
A friction facing according to claim 12 in which the cement with which the fibers of said first and second preforms are impregnated comprises from about 20 to about 80 percent, by weight, of a thermosetting resin and from about 80 to about 20 percent of a heat-curable elastomer.
Claim 20
Dependent Claim
38 words
A friction facing according to claim 17 in which said thermosetting resin is a phenol formaldehyde resin, said heat-curable elastomer is a natural rubber, and said resin and elastomer are present in said cement in substantially equal proportions.
Claim 21
Dependent Claim
22 words
A friction element according to claim 12 in which said aramid fibers have a decomposition temperature of at least about 900° F.
Claim 22
Dependent Claim
32 words
A friction facing according to claim 12 in which said aramid fibers are formed of the condensation product of terephthalic acid and p-phenylenediamine, and have a decomposition temperature of about 930° F.
Claim 23
Dependent Claim
45 words
A friction facing according to claim 12 having molded therein a plurality of holes extending from the exposed surface of said friction element into said reinforcing element, the exposed surface of said reinforcing element having been removed to a depth sufficient to expose said holes.
Claim 24
Dependent Claim
133 words
An annular friction facing comprising a friction element formed of a first tape comprising aramid fibers having a decomposition temperature of at least 850° F. impregnated with a heat-curable cement and disposed in an undulating annular fashion to form a first annular preform, and a reinforcing element formed of a second tape comprising substantially continuous glass filaments impregnated with a heat-curable cement and disposed in an undulating annular fashion to form a second annular preform, said cement with which said second tape is impregnated being compatible with that with which said first tape is impregnated, said first and second preforms having been superimposed one upon the other and subjected to heat and pressure to compress said tapes and to cure said cement to bond said preforms together to form an annular friction facing.
Claim 25
Dependent Claim
133 words
An annular friction facing comprising a friction element formed of a first tape comprising aramid fibers having a decomposition temperature of at least 850° F. impregnated with a heat-curable cement and disposed in an undulating annular fashion to form a first annular preform, and a reinforcing element formed of a second tape comprising substantially continuous glass filaments impregnated with a heat-curable cement and disposed in an undulating annular fashion to form a second annular preform, said cement with which said second tape is impregnated being compatible with that with which said first tape is impregnated, said first and second preforms having been superimposed one upon the other and subjected to heat and pressure to compress said tapes and to cure said cement to bond said preforms together to form an annular friction facing.
Claim 26
Dependent Claim
25 words
A friction facing according to claim 22 in which said first tape comprises a plurality of yarns and second tape comprises a plurality of rovings.
Claim 27
Dependent Claim
16 words
A friction facing according to claim 22 in which said first tape comprises a knitted tape.
Claim 28
Dependent Claim
18 words
A friction facing according to claim 22 in which said second tape comprises a strip of woven fabric.
Claim 29
Dependent Claim
16 words
A friction facing according to claim 23 in which said aramid fibers are substantially continuous filaments.
Claim 30
Dependent Claim
15 words
A friction facing according to claim 23 in which said aramid fibers are staple fibers.
Claim 31
Dependent Claim
29 words
A friction facing according to claim 22 in which said tape of which said first preform is composed contains up to about 30 percent, by weight, of non-aramid fibers.
Claim 32
Dependent Claim
46 words
A friction facing according to claim 22 in which said cement with which said first and second tapes are impregnated comprises from about 20 to about 80 percent, by weight, of a thermosetting resin and from about 80 to about 20 percent of a heat-curable elastomer.
Claim 33
Dependent Claim
38 words
A friction facing according to claim 8 in which said thermosetting resin is a phenol formaldehyde resin, said heat-curable elastomer is a natural rubber, and said resin and elastomer are present in said cement in substantially equal proportions.
Claim 34
Dependent Claim
22 words
A friction facing according to claim 22 in which said aramid fibers have a decomposition temperature of at least about 900° F.
Claim 35
Dependent Claim
32 words
A friction facing according to claim 22 in which said aramid fibers are formed of the condensation product of terephthalic acid and p-phenylenediamine, and have a decomposition temperature of about 930° F.
Claim 36
Dependent Claim
45 words
A friction facing according to claim 22 having molded therein a plurality of holes extending from the exposed surface of said friction element into said reinforcing element, the exposed surface of said reinforcing element having been removed to a depth sufficient to expose said holes.
Claim 37
Independent Claim
139 words
The method of forming an annular friction facing comprising: (A) forming a first tape comprising aramid fibers having a decomposition temperature of at least 850° F. impregnated with a heat-curable cement and disposing said tape in spiral or undulating annular fashion to form a first disc-shaped preform, (B) forming a second tape comprising substantially continuous glass filaments impregnated with a heat-curable cement and disposing said tape in spiral or undulating annular fashion to form a second disc-shaped preform, said cement with which said second tape is impregnated being compatible with that with which said first tape is impregnated, (C) superimposing said first and second preforms one upon the other and subjecting said superimposed preforms to heat and pressure to compress said tapes and to cure said cement to bond said preforms together to form a unitary disc-shaped friction facing.
Claim 38
Independent Claim
139 words
The method of forming an annular friction facing comprising: (A) forming a first tape comprising aramid fibers having a decomposition temperature of at least 850° F. impregnated with a heat-curable cement and disposing said tape in spiral or undulating annular fashion to form a first disc-shaped preform, (B) forming a second tape comprising substantially continuous glass filaments impregnated with a heat-curable cement and disposing said tape in spiral or undulating annular fashion to form a second disc-shaped preform, said cement with which said second tape is impregnated being compatible with that with which said first tape is impregnated, (C) superimposing said first and second preforms one upon the other and subjecting said superimposed preforms to heat and pressure to compress said tapes and to cure said cement to bond said preforms together to form a unitary disc-shaped friction facing.
Claim 39
Dependent Claim
29 words
The method according to claim 34 in which said first tape comprises a plurality of yarns and second tape comprises a plurality of rovings each impregnated with heat-curable cement.
Claim 40
Dependent Claim
15 words
The method according to claim 34 in which said first tape comprises a knitted tape.
Claim 41
Dependent Claim
17 words
The method according to claim 34 in which said second tape comprises a strip of woven fabric.
Claim 42
Dependent Claim
15 words
The method according to claim 35 in which said aramid fibers are substantially continuous filaments.
Claim 43
Dependent Claim
14 words
The method according to claim 35 in which said aramid fibers are staple fibers.
Claim 44
Dependent Claim
28 words
The method according to claim 34 in which said tape of which said first preform is composed contains up to about 30 percent, by weight, of non-aramid fibers.
Claim 45
Dependent Claim
45 words
The method according to claim 34 in which said cement with which said first and second tapes are impregnated comprises from about 20 to about 80 percent, by weight, of a thermosetting resin and from about 80 to about 20 percent of a heat-curable elastomer.
Claim 46
Dependent Claim
37 words
The method according to claim 41 in which said thermosetting resin is a phenol formaldehyde resin, said heat-curable elastomer is a natural rubber, and said resin and elastomer are present in said cement in substantially equal proportions.
Claim 47
Dependent Claim
20 words
The method of claim 34 in which said aramid fibers have a decomposition temperature of at least about 900° F.
Claim 48
Dependent Claim
31 words
The method according to claim 34 in which said aramid fibers are formed of the condensation product of terephthalic acid and p-phenylenediamine, and have a decomposition temperature of about 930° F.
Claim 49
Independent Claim
195 words
The method of forming a disc-shaped friction facing having an inner diameter and an outer diameter for use in a clutch assembly or the like comprising the steps of: (A) (1) impregnating a plurality of yarns comprising aramid fibers having a decomposition temperature of at least about 850° F. with a heat-curable cement; (2) drying said cement; (3) combining a plurality of said dry, cement-impregnated aramid fiber yarns to form a first tape; and (4) winding said first tape in undulating fashion to form a first disc-shaped preform; (B) (1) impregnating a plurality of rovings of substantially continuous glass filaments with a heat-curable cement which is compatible with the cement with which said first tape is impregnated; (2) drying said cement; (3) combining a plurality of said dry cement-impregnated glass fiber rovings to form a second tape; and (4) winding said second tape in undulating fashion to form a second disc-shaped preform; (C) (1) superimposing said first and second preforms one upon the other, and (2) subjecting said superimposed preforms to heat and pressure to compress said tapes and to cure said cement to bond said preforms together to form a unitary disc-shaped friction facing.
Claim 50
Independent Claim
195 words
The method of forming a disc-shaped friction facing having an inner diameter and an outer diameter for use in a clutch assembly or the like comprising the steps of: (A) (1) impregnating a plurality of yarns comprising aramid fibers having a decomposition temperature of at least about 850° F. with a heat-curable cement; (2) drying said cement; (3) combining a plurality of said dry, cement-impregnated aramid fiber yarns to form a first tape; and (4) winding said first tape in undulating fashion to form a first disc-shaped preform; (B) (1) impregnating a plurality of rovings of substantially continuous glass filaments with a heat-curable cement which is compatible with the cement with which said first tape is impregnated; (2) drying said cement; (3) combining a plurality of said dry cement-impregnated glass fiber rovings to form a second tape; and (4) winding said second tape in undulating fashion to form a second disc-shaped preform; (C) (1) superimposing said first and second preforms one upon the other, and (2) subjecting said superimposed preforms to heat and pressure to compress said tapes and to cure said cement to bond said preforms together to form a unitary disc-shaped friction facing.
Claim 51
Dependent Claim
15 words
The method according to claim 45 in which said aramid fibers are substantially continuous filaments.
Claim 52
Dependent Claim
14 words
The method according to claim 45 in which said aramid fibers are staple fibers.
Claim 53
Dependent Claim
28 words
The method according to claim 45 in which said tape of which said first preform is composed contains up to about 30 percent, by weight, of non-aramid fibers.
Claim 54
Dependent Claim
45 words
The method according to claim 22 in which said cement with which said first and second tapes are impregnated comprises from about 20 to about 80 percent, by weight, of a thermosetting resin and from about 80 to about 20 percent of a heat-curable elastomer.
Claim 55
Dependent Claim
37 words
The method according to claim 49 in which said thermosetting resin is a phenol formaldehyde resin, said heat-curable elastomer is a natural rubber, and said resin and elastomer are present in said cement in substantially equal properties.
Claim 56
Dependent Claim
20 words
The method of claim 45 in which said aramid fibers have a decomposition temperature of at least about 900° F.
Claim 57
Dependent Claim
31 words
The method according to claim 22 in which said aramid fibers are formed of the condensation product of terephthalic acid and p-phenylenediamine, and have a decomposition temperature of about 930° F.
Claim 58
Dependent Claim
73 words
The method according to claim 45 in which said preforms are subjected to heat and pressure in a mold having a plurality of pins which extend through said first preform and into said second preform during the molding operation, and in which the surface of the molded disc-shaped friction facing comprising glass fibers is ground to a sufficient depth to expose the holes molded into said friction facing by means of said pins.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-01-13 | 1984-07-14 | 1985-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-13 | 1988-07-14 | 1989-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-13 | 1992-07-14 | 1993-01-13 | $7700.00 | Window Closed / Lapsed |