Patent US4427742A successfully refreshed from Google Patents.
US4427742A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Core or core part for use in the lost wax casting process
Assignee: Rolls Royce PLC
•
Filing: 1981-10-29
•
Granted: 1984-01-24
•
Expires: 2001-10-29
Abstract
Abstract A core or core part for use in the lost wax casting process is strengthened by admixture to its material of a proportion of short reinforcing fibres.
Inventors
- 👤 Kenneth Willgoose
- 👤 Rondald Brien
- 👤 Peter E. Rose
- 👤 Clifford G. Hannah
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:49
CPC Classifications
B; B22; B22C; B22C9/00; B22C9/02; B22C9/04; B22C9/10; Y; Y10; Y10T; Y10T428/00; Y10T428/26; Y10T428/268; Y10T428/30
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
83 words
A core or core part shaped to define a cavity in a subsequent core or cast article adapted for use in the lost wax casting process, said core or core part comprising an admixture of distributed short reinforcing fibers dispersed but devoid of deliberate orientation in a ceramic or disposable material, the core or core part including the short reinforcing fibers distributed therein adapted for removal from the core or article into which it is at least partially embedded to define the cavity.
Claim 2
Dependent Claim
83 words
A core or core part shaped to define a cavity in a subsequent core or cast article adapted for use in the lost wax casting process, said core or core part comprising an admixture of distributed short reinforcing fibers dispersed but devoid of deliberate orientation in a ceramic or disposable material, the core or core part including the short reinforcing fibers distributed therein adapted for removal from the core or article into which it is at least partially embedded to define the cavity.
Claim 3
Dependent Claim
78 words
A core or core part shaped to define a cavity in a subsequent core or cast article and adapted for use in the lost wax casting process, said core or core part consisting essentially of a ceramic or disposable material having therein short length non-reactive fibers dispersed throughout the ceramic or disposable material and adapted for removal from the remainder of the core or from the finally cast object while enhancing the core's handling strength at low temperature.
Claim 4
Dependent Claim
78 words
A core or core part shaped to define a cavity in a subsequent core or cast article and adapted for use in the lost wax casting process, said core or core part consisting essentially of a ceramic or disposable material having therein short length non-reactive fibers dispersed throughout the ceramic or disposable material and adapted for removal from the remainder of the core or from the finally cast object while enhancing the core's handling strength at low temperature.
Claim 5
Dependent Claim
21 words
A core or core part as claimed in claim 1 or 2 in which chopped carbon fibers are the reinforcing fibers.
Claim 6
Dependent Claim
74 words
A core part adapted to be placed at least partially within the core of claim 2 for use in the lost wax casing process, said core part consisting essentially of a disposable material that is removable from the ceramic material without damage to the core in which it is at least partially contained, and having short carbon reinforcing fibres distributed throughout the disposable material, the fibre-reinforced core part exhibiting improved resistance to hydraulic force.
Claim 7
Dependent Claim
30 words
The core or core part as claimed in claim 4 wherein the short carbon fibres are readily removed from the remainder of the core or from the finally cast object.
Claim 8
Dependent Claim
31 words
A core or core part as claimed in claim 3 and in which the carbon fibre comprises about 10-15% of the material of which the core or core part is made.
Claim 9
Dependent Claim
29 words
A core or core part as claimed in claim 3 and in which said carbon fibre comprises fibres of about 7-10 microns diameter and of about 0.010" in length.
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) | 1987-01-23 | 1987-07-25 | 1988-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-23 | 1991-07-25 | 1992-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-23 | 1995-07-25 | 1996-01-24 | $7700.00 | Window Closed / Lapsed |