US3838495A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming closed sheet metal structures with an internal corrosion-resistant coating
Assignee: Bayerische Motoren Werke AG
•
Filing: 1972-03-24
•
Granted: 1974-10-01
•
Expires: 1992-03-24
Abstract
Abstract This invention provides a method of forming partially or completely closed sheet metal structures having a corrosionresistant coating on the internal surface thereof by welding together shaped sheet metal parts to join the structure. In the method, the parts are formed from unshaped sheet metal stock having on at least one side thereof a coating of a coating material having a high content of one or more metals and/or graphite. The coating material is resistant to deep-drawing, is electrically conductive and is suitable for welding. The parts are formed in such a manner that the coated side will form the internal surface of the part in the assembled structure.
Inventors
- 👤 A Kuhnert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:17
CPC Classifications
B; B05; B05D; B05D3/00; B05D3/12; B62; B62D; B62D25/00; B62D25/02; B62D25/025; B62D25/20; B62D25/2009; B62D25/2036; B62D25/2072; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49826; Y10T29/49885; Y10T29/4998; Y10T29/49982
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
79 words
IN A PROCESS FOR PRODUCING PARTIALLY OR COMPLETELY CLOSED SHEET STEEL STRUCTURES HAVING A CORRISION-RESISTANT COATING ON THE INNER SURFACE THEREOF BY A FIRST APPLYING A COATING WHICH IS ELECTRICALLY CONDUCTIVE, CAPABLE OF BEING DEEP DRAWN WITHOUT DAMAGING THE COATING AND SUITABLE FOR WELDING ON AT LEAST ONE SURFACE OF UNSHAPED SHEETS OF STEEL,DEEP DRAWING THE COATED SHEETS TO FORM PAETS OF THE DESIRED SHAPE AND WELDING THE DEEP DRAWN COATED PARTS TOGETHER TO FORM A SHEET STEEL STRUCTURE
Claim 2
Dependent Claim
79 words
IN A PROCESS FOR PRODUCING PARTIALLY OR COMPLETELY CLOSED SHEET STEEL STRUCTURES HAVING A CORRISION-RESISTANT COATING ON THE INNER SURFACE THEREOF BY A FIRST APPLYING A COATING WHICH IS ELECTRICALLY CONDUCTIVE, CAPABLE OF BEING DEEP DRAWN WITHOUT DAMAGING THE COATING AND SUITABLE FOR WELDING ON AT LEAST ONE SURFACE OF UNSHAPED SHEETS OF STEEL,DEEP DRAWING THE COATED SHEETS TO FORM PAETS OF THE DESIRED SHAPE AND WELDING THE DEEP DRAWN COATED PARTS TOGETHER TO FORM A SHEET STEEL STRUCTURE
Claim 3
Dependent Claim
22 words
A method according to claim 1 wherein the coating material is selected from the group consisting of synthetic resin paints and varnishes.
Claim 4
Dependent Claim
34 words
A method according to claim 2 wherein the coating material contains at least 50 percent by weight of at least one material selected from the group comprising aluminium powder, zinc powder and graphite powder.
Claim 5
Dependent Claim
19 words
A method according to claim 2 wherein the sheet metal structure is subsequently subjected to an electrophoretic primer dip-coating.
Claim 6
Dependent Claim
12 words
A method according to claim 1 wherein the metal is zinc powder.
Claim 7
Dependent Claim
12 words
A method according to claim 1 wherein the metal is aluminium powder.
Claim 8
Dependent Claim
65 words
A method according to claim 1 wherein the hardenable bonding agent comprises from 60 to 95 percent by weight of an epoxy resin having free hydroxyl groups and having an OH number of from 0.35 to 0.50 mol OH/100 g resin and of from 40 to 5 per cent by weight of polyfunctional compound selected from the group comprising poly-isocyanates, thioplasts and fully blocked aminoplasts.
Claim 9
Dependent Claim
128 words
In a process for producing partially or completely clolsed sheet steel structures having a corrosion-resistant coating on the inner surface thereof by first applying a coating which is electrically conductive, capable of resisting high forming stresses and is suitable for welding, on at least one surface of unshaped sheets of steel deforming the sheets steel parts of the desired shape and welding the deformed parts together to form a steel metal structure having a coated surface on the inside, the improvements wherein the coating is applied to the unshaped sheets of steel by means of a coating material having a high metal and/or graphite content and comprising metal powder and/or graphite powder and a synthetic resin hardenable bonding agent and the welding is accomplished by electrical resistance welding.
Claim 10
Dependent Claim
128 words
In a process for producing partially or completely clolsed sheet steel structures having a corrosion-resistant coating on the inner surface thereof by first applying a coating which is electrically conductive, capable of resisting high forming stresses and is suitable for welding, on at least one surface of unshaped sheets of steel deforming the sheets steel parts of the desired shape and welding the deformed parts together to form a steel metal structure having a coated surface on the inside, the improvements wherein the coating is applied to the unshaped sheets of steel by means of a coating material having a high metal and/or graphite content and comprising metal powder and/or graphite powder and a synthetic resin hardenable bonding agent and the welding is accomplished by electrical resistance welding.
Claim 11
Dependent Claim
19 words
A method according to claim 8 wherein the coated side has been phosphatized prior to application of the coating.
Claim 12
Dependent Claim
32 words
A method according to claim 8 wherein the coating material contains at least 50 per cent by weight of at least one material selected from the group consisting of metals and graphite.
References Cited (Backward Citations)
US181356A
Cited
US1548514A
Cited
US2140131A
Cited
US3252215A
Cited
US3153990A
Cited
US3293896A
Cited
US3689941A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-30 | 1978-04-01 | 1978-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-30 | 1982-04-01 | 1982-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-30 | 1986-04-01 | 1986-10-01 | $7700.00 | Window Closed / Lapsed |