US4726852A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing bowl-like metal article
Assignee: Nissan Motor Co Ltd
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Filing: 1986-07-30
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Granted: 1988-02-23
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Expires: 2006-07-30
Abstract
Abstract The invention relates to a method of producing a bowl-like metal article, e.g. a half of a spherical rocket motor case made of a titanium alloy, by first shaping a flat blank into a bowl-like shape by a press forming operation and subsequently making heat treatment of the bowl-like work. Following the press forming operation, the shape of the bowl-like work is corrected by spinning. At the heat treatment a templet member is used to keep the bowl-like work in a restrained state so as to correct possible irregular straining and distortion of the work. Preferably the templet is a bowl-like member designed and disposed such that its outer surface comes into close contact with the inner surface of the bowl-like work by thermal expansion at the heat treatment. Both the thickness of the blank and the amount of machining on the heat-treated work can be reduced.
Inventors
- 👤 Megumi Nakanose
- 👤 Yutaka Sohara
- 👤 Hiroyuki Tanaka
- 👤 Shinsaku Hamada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:03
CPC Classifications
C; C21; C21D; C21D9/00; C21D9/0006; C21D9/0025; B; B21; B21D; B21D22/00; B21D22/14; B21D51/00; B21D51/16; B21D51/24; B23; B23P; B23P9/00; B23P9/02
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
303 words
A method of producing a bowl-like metal article, comprising the steps of: shaping a metal blank in the form of a circular plate into a bowl-like member having a concave inner surface and an open end by a press forming operation; correcting the shape of said bowl-like member by a spinning operation; after the shape correcting step, securing said bowl-like member in a region near the open end to a transferable annular base support means; securing a templet member, having a convex outer surface shaped to correspond to said concave inner surface of said bowl-like member and formed of material having a coefficient of expansion greater than the coefficient of expansion of the material of said bowl-like member and made such that when said bowl-like member and said templet member are cooled together from an elevated temperature said templet member will cool at a lower rate than said bowl-like member, to said support means so that said convex outer surface of said templet member is initially at such a short distance from said concave inner surface of said bowl-like member that when said bowl-like member and said templet member are heated to a predetermined temperature said convex outer surface comes into contact with said concave inner surface of said bowl-like member by thermal expansion; heating said bowl-like member together with said templet member while they are secured to said support means to a heat treatment temperature which is an elevated temperature not lower than the predetermined temperature, to keep said bowl-like member in a restrained state and correct irregular straining and distortion of said bowl-like member under heat treatment; and rapidly cooling the heated bowl-like member together with said templet member while said convex outer surface of said templet member is still in contact with said concave inner surface of said bowl-like member.
Claim 2
Independent Claim
303 words
A method of producing a bowl-like metal article, comprising the steps of: shaping a metal blank in the form of a circular plate into a bowl-like member having a concave inner surface and an open end by a press forming operation; correcting the shape of said bowl-like member by a spinning operation; after the shape correcting step, securing said bowl-like member in a region near the open end to a transferable annular base support means; securing a templet member, having a convex outer surface shaped to correspond to said concave inner surface of said bowl-like member and formed of material having a coefficient of expansion greater than the coefficient of expansion of the material of said bowl-like member and made such that when said bowl-like member and said templet member are cooled together from an elevated temperature said templet member will cool at a lower rate than said bowl-like member, to said support means so that said convex outer surface of said templet member is initially at such a short distance from said concave inner surface of said bowl-like member that when said bowl-like member and said templet member are heated to a predetermined temperature said convex outer surface comes into contact with said concave inner surface of said bowl-like member by thermal expansion; heating said bowl-like member together with said templet member while they are secured to said support means to a heat treatment temperature which is an elevated temperature not lower than the predetermined temperature, to keep said bowl-like member in a restrained state and correct irregular straining and distortion of said bowl-like member under heat treatment; and rapidly cooling the heated bowl-like member together with said templet member while said convex outer surface of said templet member is still in contact with said concave inner surface of said bowl-like member.
Claim 3
Dependent Claim
16 words
A method according to claim 1, wherein said press forming operation is hot press forming operation.
Claim 4
Dependent Claim
24 words
A method according to claim 1 further comprising the step of grinding the surfaces of said bowl-like member precedent to the shape correcting step.
Claim 5
Dependent Claim
16 words
A method according to claim 1, wherein said press forming operation is cold press forming operation.
Claim 6
Dependent Claim
31 words
A method according to claim 1, wherein an inactive gas is introduced into the space between said outer surface of said templet member and the inner surface of said bowl-like member.
Claim 7
Dependent Claim
21 words
A method according to claim 1, wherein a diffusion bonding inhibitor is applied to said outer surface of said templet member.
Claim 8
Dependent Claim
15 words
A method acccording to claim 1, wherein said metal is titanium or a titanium alloy.
Claim 9
Dependent Claim
19 words
A method according to claim 1, wherein said bowl-like metal article is a part of a rocket motor case.
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) | 1991-02-22 | 1991-08-24 | 1992-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-22 | 1995-08-24 | 1996-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-22 | 1999-08-24 | 2000-02-23 | $7700.00 | Window Closed / Lapsed |