Patent US1914262A successfully refreshed from Google Patents.
US4844007A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for providing glass layers on the inside of a tube
Assignee: US Philips Corp
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Filing: 1987-11-02
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Granted: 1989-07-04
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Expires: 2007-11-02
Abstract
Abstract A device for providing glass layers on the inside of a tube according to the PCVD process. In this process a microwave resonator is reciprocated along a tube. The resonator, on the side facing the tube, is provided partly with a heat-insulating layer. Said layer may consist of SiO 2 , Al 2 O 3 , TiO 2 or MgO.
Inventors
- 👤 Herman W. Eikelboom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 03:52
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/01; C03B37/012; C03B37/014; C03B37/018; C03B37/01807; C03B37/01815; C03B37/01823; C03B37/0183
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
185 words
A device for providing glass layers on the inside of a tube, comprising a gas supply device which is connected to one end of the tube, a furnace for heating the tube, a resonator comprising a resonant cavity for generating a plasma in the tube, said plasma being capable of delivering thermal energy to the tube in a quantity ranging from a maximum to less than 40% of the maximum, and means to move the resonator and the tube relatively with respect to each other, a high-frequency generator which is connected to the resonant cavity, and a vacuum pump which is connected to the opposite end of the tube, characterized in that the resonator comprises a cooled body comprising a duct for receiving the tube, of which body at least the wall of the duct consists of a readily heat-conducting metal and in which the wall of the duct facing the tube comprises a heat-insulating layer over only that part within which during operation of the device less than 40% of the maximum quantity of thermal energy is delivered by the plasma in the tube.
Claim 2
Independent Claim
185 words
A device for providing glass layers on the inside of a tube, comprising a gas supply device which is connected to one end of the tube, a furnace for heating the tube, a resonator comprising a resonant cavity for generating a plasma in the tube, said plasma being capable of delivering thermal energy to the tube in a quantity ranging from a maximum to less than 40% of the maximum, and means to move the resonator and the tube relatively with respect to each other, a high-frequency generator which is connected to the resonant cavity, and a vacuum pump which is connected to the opposite end of the tube, characterized in that the resonator comprises a cooled body comprising a duct for receiving the tube, of which body at least the wall of the duct consists of a readily heat-conducting metal and in which the wall of the duct facing the tube comprises a heat-insulating layer over only that part within which during operation of the device less than 40% of the maximum quantity of thermal energy is delivered by the plasma in the tube.
Claim 3
Dependent Claim
40 words
A device as claimed in claim 1, characterized in that the heat-insulating layer consists of fibres and/or grains of one or more substances from the group consisting of SiO 2 , Al 2 O 3 , TiO 2 and MgO.
References Cited (Backward Citations)
US4714589A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-03 | 1993-01-02 | 1993-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-03 | 1997-01-02 | 1997-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-03 | 2001-01-02 | 2001-07-04 | $7700.00 | Window Closed / Lapsed |