Patent US4253245A successfully refreshed from Google Patents.
US4253245A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for controlling the flow of steam in paper machine dryers
Assignee: Union Camp Corp
•
Filing: 1979-09-19
•
Granted: 1981-03-03
•
Expires: 1999-09-19
Abstract
Abstract This disclosure is of a device for controlling the flow of steam in paper machine dryers wherein a positive displacement pump is used to create differential and condensate evacuation from the paper machine dryers. This invention is applicable to a single steam heated drum or a plurality of such drums. It can be used in either a recirculating or cascading system.
Inventors
- 👤 Robert D. Perrault
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 22:20
CPC Classifications
D; D21; D21F; D21F5/00; D21F5/02; D21F5/022; D21F5/028
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
147 words
In a dryer and drainage system including at least one dryer section, each section having at least one dryer drum, a device for controlling the flow of steam through each section comprising: means for feeding steam into the dryer section; a device for controlling the pressure of steam into the dryer section; a separator connected to the dryer section for drawing off steam and condensate therefrom; said separator maintaining a condensate level therein; a pipe connected to said separator above the condensate level for drawing off blowthru steam therefrom; and a gas pump to which the said pipe is connected, said pump being positioned between the said separator and the dryer section and being set to a predetermined speed to control the desired rate of flow of steam from the said separator into the dryer section; whereby the required pressure differential for all conditions is automatically controlled.
Claim 2
Dependent Claim
147 words
In a dryer and drainage system including at least one dryer section, each section having at least one dryer drum, a device for controlling the flow of steam through each section comprising: means for feeding steam into the dryer section; a device for controlling the pressure of steam into the dryer section; a separator connected to the dryer section for drawing off steam and condensate therefrom; said separator maintaining a condensate level therein; a pipe connected to said separator above the condensate level for drawing off blowthru steam therefrom; and a gas pump to which the said pipe is connected, said pump being positioned between the said separator and the dryer section and being set to a predetermined speed to control the desired rate of flow of steam from the said separator into the dryer section; whereby the required pressure differential for all conditions is automatically controlled.
Claim 3
Dependent Claim
21 words
The device of claim 1 wherein there are a plurality of sections with each section having at least one dryer drum.
Claim 4
Dependent Claim
25 words
The device of claim 1 wherein the gas pump has a variable speed drive whereby the desired rate of flow of steam can be varied.
Claim 5
Dependent Claim
37 words
The device of claim 1 wherein the steam from the separator is fed by the gas pump back to the means for feeding steam into the dryer section whereby the steam is recirculated through the dryer section.
Claim 6
Dependent Claim
45 words
The device of claim 2 wherein the steam from the separator of the first dryer section is fed by the gas pump to the means for feeding steam into the second dryer section whereby the steam is cascaded from one section to the next section.
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) | 1984-03-02 | 1984-09-01 | 1985-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-02 | 1988-09-01 | 1989-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-02 | 1992-09-01 | 1993-03-03 | $7700.00 | Window Closed / Lapsed |