Patent US3110614A successfully refreshed from Google Patents.
US3564328A
Expired / Lapsed
US
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Ceramic articles and method of fabrication
Assignee: Corning Glass Works
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Filing: 1968-07-29
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Granted: 1971-02-16
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Expires: 1988-07-29
Abstract
Abstract Method of forming gas tight seals between polycrystalline ceramic bodies without a sealant material. Method, which is useful for joining sections of ceramic tubing in gastight relationship and for providing gastight seals for tubular bodies, depends on differing degrees of firing shrinkage of the components being joined, their ability to sinter together, and on the fact that the components, when fired, have substantially the same coefficient of thermal expansion. Various means of providing for differential firing shrinkages, such as a polycrystalline ceramic tube fired to near theoretical density is inserted in closely fitted relationship into a green tubular body of the same composition and the assembly is fired until both components are of maximum density. Sintering and shrinkage of the outer tubular body onto the inner body produces a monolithic structure with a completely continuous crystal structure across and replacing the former physical contact boundary. Ceramic articles, such as gas discharge lamp structures, embodying tubular ceramic bodies having end closures made by described method.
Inventors
- 👤 Rodney D Bagley
- 👤 Edwin J Force
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:18
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/111; C04B35/115; C04B37/00; C04B37/001; H; H01; H01J; H01J61/00; H01J61/02; H01J61/30; H01J61/302; H01J9/00; H01J9/24; H01J9/26; H01J9/265; H01J9/266; C04B2235/00; C04B2235/02; C04B2235/30; C04B2235/32; C04B2235/3217; C04B2235/322; C04B2235/50; C04B2235/54; C04B2235/5418; C04B2235/5445; C04B2235/5454; C04B2235/5463; C04B2235/65; C04B2235/66; C04B2235/661; C04B2235/70; C04B2235/96; C04B2235/9607; C04B2235/9615; C04B2237/00; C04B2237/30; C04B2237/32; C04B2237/34; C04B2237/343; C04B2237/50; C04B2237/70; C04B2237/704; C04B2237/76; C04B2237/765; C04B2237/80; C04B2237/84
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
190 words
The method of producing a monolithic polycrystalline ceramic body from at least two component members formed of sinterable polycrystalline ceramic material, at least one of said members being a tubular body, said method comprising: providing at least another one of said members having; essentially the same coefficient of thermal expansion when sintered as that of said tubular body when sintered, an external circumferential surface portion that closely fits an internal circumferential surface portion of said tubular body, and a firing shrinkage substantially less than that of said tubular body to cause said surfaces to firmly and intimately contact each other with pressure developed therebetween when assembled in circumferentially contiguous telescoped relationship and when the so assembled members are fired to the sintering temperature of said material, assembling directly together said members with said surfaces in said relationship; and firing said assembled members to said temperature to effect sintering thereof with development of said shrinkage and of said resulting contact of said surfaces, and to contemporaneously effect sintering together of said contacting surfaces with development of a completely continuous crystal structure across and that replaces the former physical contact boundary therebetween.
Claim 2
Independent Claim
190 words
The method of producing a monolithic polycrystalline ceramic body from at least two component members formed of sinterable polycrystalline ceramic material, at least one of said members being a tubular body, said method comprising: providing at least another one of said members having; essentially the same coefficient of thermal expansion when sintered as that of said tubular body when sintered, an external circumferential surface portion that closely fits an internal circumferential surface portion of said tubular body, and a firing shrinkage substantially less than that of said tubular body to cause said surfaces to firmly and intimately contact each other with pressure developed therebetween when assembled in circumferentially contiguous telescoped relationship and when the so assembled members are fired to the sintering temperature of said material, assembling directly together said members with said surfaces in said relationship; and firing said assembled members to said temperature to effect sintering thereof with development of said shrinkage and of said resulting contact of said surfaces, and to contemporaneously effect sintering together of said contacting surfaces with development of a completely continuous crystal structure across and that replaces the former physical contact boundary therebetween.
Claim 3
Dependent Claim
54 words
The method of claim 1 wherein said lesser shrinkage of said another one member is sufficient to effect a restraining action by said another one member on the shrinkage of said portion of said tubular body during said firing accompanied by the development of a bulged-out configuration in said portion of said tubular body.
Claim 4
Dependent Claim
15 words
The method of claim 1 wherein said polycrystalline ceramic consists essentially of polycrystalline ceramic oxide.
Claim 5
Dependent Claim
11 words
The method of claim 3 wherein said oxide is alpha alumina.
Claim 6
Dependent Claim
28 words
The method of claim 1 wherein said another one member is a barrel-shaped plug and said portion of said tubular body is axially adjacent to an end thereof.
Claim 7
Dependent Claim
83 words
The method of claim 1 wherein: said polycrystalline ceramic consists essentially of alpha alumina; said another one member is a barrel-shaped plug and said portion of said tubular body is axially adjacent to an end thereof; and said lesser shrinkage of said another one member is sufficient to effect a restraining action by said plug on the shrinkage of said portion of said tubular body during said firing accompanied by the development of a bulged-out configuration in said portion of said tubular body.
Claim 8
Independent Claim
198 words
The method of hermetically sealing directly together at least two polycrystalline ceramic bodies to form a monolithic structure wherein said bodies are formed of sinterable polycrystalline ceramic material and at least one of said bodies is a tubular body, said method comprising: providing at least another one of said bodies having; essentially the same coefficient of thermal expansion when sintered as that of said tubular body when sintered, an external circumferential surface portion that closely fits an internal circumferential surface portion of said tubular body, and a firing shrinkage substantially less than that of said tubular body to cause said surfaces to firmly and intimately contact each other with pressure developed therebetween when assembled in circumferentially contiguous telescoped relationship and when the so assembled members are fired to the sintering temperature of said material, assembling directly together said members with said surfaces in said relationship; and firing said assembled members to said temperature to effect sintering thereof with development of said shrinkage and of said resulting contact of said surfaces, and to contemporaneously effect sintering together of said contacting surfaces with development of a completely continuous crystal structure across and that replaces the former physical contact boundary therebetween.
Claim 9
Independent Claim
198 words
The method of hermetically sealing directly together at least two polycrystalline ceramic bodies to form a monolithic structure wherein said bodies are formed of sinterable polycrystalline ceramic material and at least one of said bodies is a tubular body, said method comprising: providing at least another one of said bodies having; essentially the same coefficient of thermal expansion when sintered as that of said tubular body when sintered, an external circumferential surface portion that closely fits an internal circumferential surface portion of said tubular body, and a firing shrinkage substantially less than that of said tubular body to cause said surfaces to firmly and intimately contact each other with pressure developed therebetween when assembled in circumferentially contiguous telescoped relationship and when the so assembled members are fired to the sintering temperature of said material, assembling directly together said members with said surfaces in said relationship; and firing said assembled members to said temperature to effect sintering thereof with development of said shrinkage and of said resulting contact of said surfaces, and to contemporaneously effect sintering together of said contacting surfaces with development of a completely continuous crystal structure across and that replaces the former physical contact boundary therebetween.
Claim 10
Dependent Claim
92 words
An article of manufacture having a monolithic structure and comprising at least two polycrystalline ceramic members hermetically sinter-sealed directly together at an apparent circumferential boundary therebetween, all of said members having essentially the same coefficient of thermal expansion, at least one of said members being tubular, circumferential portion of said tubular member being embracive in circumferentially contiguous telescoped relationship of and constituting said boundary with at least a circumferential portion of at least one other of said members, and wherein said monolithic structure includes a completely continuous crystal structure across said boundary.
Claim 11
Dependent Claim
92 words
An article of manufacture having a monolithic structure and comprising at least two polycrystalline ceramic members hermetically sinter-sealed directly together at an apparent circumferential boundary therebetween, all of said members having essentially the same coefficient of thermal expansion, at least one of said members being tubular, circumferential portion of said tubular member being embracive in circumferentially contiguous telescoped relationship of and constituting said boundary with at least a circumferential portion of at least one other of said members, and wherein said monolithic structure includes a completely continuous crystal structure across said boundary.
Claim 12
Dependent Claim
15 words
The article of claim 8 wherein said polycrystalline ceramic consists essentially of polycrystalline ceramic oxide.
Claim 13
Dependent Claim
11 words
The article of claim 9 wherein said oxide is alpha alumina.
Claim 14
Dependent Claim
42 words
The article of claim 8 wherein said one other member is a second tubular member with said portion thereof being axially adjacent to an end thereof and said portion of said first named tubular member is axially adjacent to an end thereof.
Claim 15
Dependent Claim
22 words
The article of claim 11 wherein said first named tubular member is a cap with said portion thereof being a tubular skirt.
Claim 16
Dependent Claim
27 words
The article of claim 8 wherein said one other member is a plug and said portion of said tubular member is axially adjacent to an end thereof.
Claim 17
Dependent Claim
181 words
An electric arc discharge lamp comprising a. an envelope comprising: i. a tubular light-transmissive polycrystalline ceramic member, ii. a pair of apertured polycrystalline ceramic closure members closing opposite ends of said tubular member and being monolithically hermetically sinter-sealed directly thereto at an apparent circumferential boundary between said tubular member and each of said closure members, iii. all of said members having essentially the same coefficient of thermal expansion, iv. at each end of said tubular member, one of said tubular and closure members having a circumferential portion embracive in circumferentially contiguous telescoped relationship of and constituting said boundary with at least a circumferential portion of the other of said tubular and closure members, and v. a monolithic structure that includes a completely continuous crystal structure across said boundary, b. at least a pair of electrodes contained within saId envelope and mounted on hermetically sealed electrode support members; c. said electrode support members positioned through each of said apertured closure members and hermetically sealed thereto d. a charge of an inert ionizable starting gas and a vaporizable light-emitting substance within said envelope.
Claim 18
Dependent Claim
181 words
An electric arc discharge lamp comprising a. an envelope comprising: i. a tubular light-transmissive polycrystalline ceramic member, ii. a pair of apertured polycrystalline ceramic closure members closing opposite ends of said tubular member and being monolithically hermetically sinter-sealed directly thereto at an apparent circumferential boundary between said tubular member and each of said closure members, iii. all of said members having essentially the same coefficient of thermal expansion, iv. at each end of said tubular member, one of said tubular and closure members having a circumferential portion embracive in circumferentially contiguous telescoped relationship of and constituting said boundary with at least a circumferential portion of the other of said tubular and closure members, and v. a monolithic structure that includes a completely continuous crystal structure across said boundary, b. at least a pair of electrodes contained within saId envelope and mounted on hermetically sealed electrode support members; c. said electrode support members positioned through each of said apertured closure members and hermetically sealed thereto d. a charge of an inert ionizable starting gas and a vaporizable light-emitting substance within said envelope.
Claim 19
Dependent Claim
45 words
The electric arc discharge lamp of claim 14 in which the apertures of the apertured closure members are outwardly tapering in configuration and those portions of the electrode support members which are hermetically sealed to said apertured closure members are complementarily inwardly tapering in configuration.
Claim 20
Dependent Claim
19 words
The electric arc discharge lamp of claim 14 in which the polycrystalline ceramic consists essentially of polycrystalline ceramic oxide.
Claim 21
Dependent Claim
17 words
The electric arc discharge lamp of claim 14 in which the polycrystalline ceramic consists essentially of alumina.
Claim 22
Dependent Claim
34 words
The electrical arc discharge lamp of claim 14 in which the apertured closure members are in the form of caps having skirt members embracive of the ends of the tubular light-transmissive polycrystalline ceramic member.
Claim 23
Dependent Claim
29 words
The electrical arc discharge lamp of claim 14 in which the aperture apertured closure members are in the form of plugs positioned within the tubular light-transmissive polycrystalline ceramic member.
References Cited (Backward Citations)
US1456960A
Cited
US3184370A
Cited
US3192086A
Cited
US3239322A
Cited
US3239323A
Cited
US3346357A
Cited
US3416980A
Cited
US3363134A
Cited
US3363133A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-02-15 | 1974-08-17 | 1975-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-15 | 1978-08-17 | 1979-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-15 | 1982-08-17 | 1983-02-16 | $7700.00 | Window Closed / Lapsed |