US3844027A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Copper brazing of matrix structures
Assignee: Old Carco LLC
•
Filing: 1973-06-25
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Granted: 1974-10-29
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Expires: 1993-06-25
Abstract
Abstract A method of applying copper brazing material to matrix structures, such as turbine engine regenerator cores, for copper brazing them.
Inventors
- 👤 F Hagen
- 👤 R Davis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:18
CPC Classifications
B; B23; B23K; B23K1/00; B23K1/20; B23K1/0008; B23K1/0014; B23K35/00; B23K35/02; B23K35/0222; B23K35/0244; B23K35/025; B23K35/22; B23K35/34; B23K2101/00; B23K2101/02; B23K2103/00; B23K2103/08; B23K2103/12
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
81 words
A METHOD OF UNIFORMLY APPLYING COPPER BRACING MATERIAL TO MATRIX ASSEMBLIES FOR THE SUBSEQUENT COPPER BRAZING THEREOF, COMPRISING THE STEPS: A. PREPARING A SLURRY OF COPPER BRAZING PASTE TO FORM A BRAZING MATERIAL, B. PLACING THE SLURRY ON ONE FACE OF THE MATRIX ASSEMBLY SO AS TO INTRODUCE IT TO THE PASSAGEWAYS THEREOF, AND C. ESTABLISHING A PRESSURE DIFFERENTIAL BETWEEN THE FACES OF THE MATRIX ASSEMBLY WHEREBY THE SLURRY IS CAUSED TO FLOW THROUGH THE PASSAGEWAYS AND COAT THE INTERIOR THEREOF.
Claim 2
Independent Claim
81 words
A METHOD OF UNIFORMLY APPLYING COPPER BRACING MATERIAL TO MATRIX ASSEMBLIES FOR THE SUBSEQUENT COPPER BRAZING THEREOF, COMPRISING THE STEPS: A. PREPARING A SLURRY OF COPPER BRAZING PASTE TO FORM A BRAZING MATERIAL, B. PLACING THE SLURRY ON ONE FACE OF THE MATRIX ASSEMBLY SO AS TO INTRODUCE IT TO THE PASSAGEWAYS THEREOF, AND C. ESTABLISHING A PRESSURE DIFFERENTIAL BETWEEN THE FACES OF THE MATRIX ASSEMBLY WHEREBY THE SLURRY IS CAUSED TO FLOW THROUGH THE PASSAGEWAYS AND COAT THE INTERIOR THEREOF.
Claim 3
Dependent Claim
13 words
The method of claim 1 including the additional step of drying the assembly.
Claim 4
Dependent Claim
20 words
The method of claim 2 including the additional steps of heating and cooling the assembly to cause the brazing thereof.
Claim 5
Dependent Claim
12 words
The method of claim 1 wherein the brazing paste contains Cu2O particles.
Claim 6
Dependent Claim
13 words
The method of claim 1 wherein the brazing paste contains metallic copper particles.
Claim 7
Dependent Claim
15 words
The method of claim 1 wherein the slurry vehicle for the brazing paste is water.
Claim 8
Dependent Claim
24 words
The method of claim 5 wherein the viscosity (No. 4 Ford cup) of the slurry is adjusted to between about 55 to 60 seconds.
Claim 9
Dependent Claim
20 words
The method of claim 1 wherein a positive pressure is established and maintained above the slurry through the passageways thereof.
Claim 10
Dependent Claim
30 words
The method of claim 8 wherein the pressure is established by enclosing the face and providing air pump means to pump air into the enclosure thus establishing the positive pressure.
Claim 11
Dependent Claim
32 words
The method according to claim 9 wherein air is blown through the passageways following the passage of the slurry therethrough, maintaining the passage of air until the slurry coating is substantially dry.
Claim 12
Dependent Claim
24 words
The method according to claim 9 including the additional step of removing any slurry drip edge formed on the second face of the matrix.
Claim 13
Dependent Claim
34 words
The method according to claim 1 wherein slurry is applied until the matrix shows a dry weight increase of at least about 8 percent but less than about 10 percent over its original weight.
Claim 14
Dependent Claim
16 words
The method of claim 1 wherein the slurry is formed by diluting a copper brazing paste.
Claim 15
Dependent Claim
10 words
The method of claim 13 wherein the diluent is water.
References Cited (Backward Citations)
US2962811A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-28 | 1978-04-29 | 1978-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-28 | 1982-04-29 | 1982-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-28 | 1986-04-29 | 1986-10-29 | $7700.00 | Window Closed / Lapsed |