Patent DE2803757C3 successfully refreshed from Google Patents.
US4549933A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Doctor blade with non-homogeneous stiffness properties
Assignee: Thermo Web Systems Inc
•
Filing: 1983-07-05
•
Granted: 1985-10-29
•
Expires: 2003-07-05
Abstract
Abstract A composite doctor blade with non-homogeneous stiffness properties and having a plurality of juxtaposed fibrous layers which are encapsulated in an epoxy resin. The composite blade has a fibrous core, intermediate uni-directional graphite fiber layers and outer fibrous layers. The uni-directional graphite fibers in the intermediate layers are oriented in the machine direction.
Inventors
- 👤 Michael Judd
- 👤 Joseph S. Cooper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:07
CPC Classifications
D; D21; D21G; D21G3/00; D21G3/005; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24058; Y10T428/24124
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
93 words
An elongated doctor blade having a side edge structured for application to a roll surface in a paper making machine, said blade comprising: an inner first layer of fibrous material lying on a neutral axis of said blade, and a plurality of second layers juxtaposed on opposite sides of said inner first layer, said second layers having uni-directional graphite fibers oriented so as to provide said blade with a stiffness in the direction perpendicular to said edge which is greater than the stiffness of said blade in the direction parallel to said edge.
Claim 2
Dependent Claim
93 words
An elongated doctor blade having a side edge structured for application to a roll surface in a paper making machine, said blade comprising: an inner first layer of fibrous material lying on a neutral axis of said blade, and a plurality of second layers juxtaposed on opposite sides of said inner first layer, said second layers having uni-directional graphite fibers oriented so as to provide said blade with a stiffness in the direction perpendicular to said edge which is greater than the stiffness of said blade in the direction parallel to said edge.
Claim 3
Dependent Claim
15 words
The doctor blade of claim 1 wherein said uni-directional fibers are perpendicular to said edge.
Claim 4
Dependent Claim
14 words
The doctor blade of claim 1 further comprising third layers overlying said second layers.
Claim 5
Dependent Claim
26 words
The doctor blade of claim 3 wherein said first and third layers include multi-directional fibers, at least some of which are not perpendicular to said edge.
Claim 6
Dependent Claim
16 words
The doctor blade of claim 3 wherein said third layers have a thickness of about 0.005".
Claim 7
Dependent Claim
21 words
The doctor blade of claim 1 wherein said second layers each have a thickness in the range of 0.005" to 0.025".
Claim 8
Dependent Claim
24 words
The doctor blade of either claims 1 or 6 wherein the thickness of said first layer is in the range of 0.005" to 0.025".
Claim 9
Dependent Claim
16 words
The doctor blade of claim 1 wherein said second layers are encapsulated in an epoxy resin.
Claim 10
Dependent Claim
23 words
The doctor blade of claim 1 wherein the combined thickness of said first and second layers in the range of 0.025" to 0.070".
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) | 1988-10-28 | 1989-04-29 | 1989-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-28 | 1993-04-29 | 1993-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-28 | 1997-04-29 | 1997-10-29 | $7700.00 | Window Closed / Lapsed |