Patent US4438804A successfully refreshed from Google Patents.
US4438804A
Expired / Lapsed
US
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Water soluble cores and method for manufacturing cast rotor provided with ventilation ducts utilizing the core
Assignee: Toshiba Corp
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Filing: 1981-11-13
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Granted: 1984-03-27
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Expires: 2001-11-13
Abstract
Abstract A water soluble core comprises a mold product prepared by a mixture of sand, potassium carbonate as a first binder and at least one of barium carbonate and alkali silicate as a second binder. This water soluble core is utilized for a method of manufacturing a cast rotor for forming ventilation ducts of an induction motor.
Inventors
- 👤 Toshiro Aiga
- 👤 Toshiaki Maeda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:52
CPC Classifications
B; B22; B22C; B22C9/00; B22C9/10; B22C9/105
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
119 words
A water soluble core comprising a mold product prepared from a mixture consisting essentially of a sand in an amount of 100 parts by weight, a first binding agent of potassium carbonate in an amount of 10-50 parts by weight, and a second binding agent selected from the group consisting of at least one of barium carbonate in an amount of 1-50 parts by weight and 1-15 parts by weight of alkali silicate, and wherein said water soluble core is prepared by kneading a mixture of said sand, said first and second binding agents, and 5-20 parts by weight of water based on 100 parts by weight of said sand and said water soluble core is dried after molding.
Claim 2
Dependent Claim
119 words
A water soluble core comprising a mold product prepared from a mixture consisting essentially of a sand in an amount of 100 parts by weight, a first binding agent of potassium carbonate in an amount of 10-50 parts by weight, and a second binding agent selected from the group consisting of at least one of barium carbonate in an amount of 1-50 parts by weight and 1-15 parts by weight of alkali silicate, and wherein said water soluble core is prepared by kneading a mixture of said sand, said first and second binding agents, and 5-20 parts by weight of water based on 100 parts by weight of said sand and said water soluble core is dried after molding.
Claim 3
Dependent Claim
23 words
A water soluble core as claimed in claim 1, wherein said second binding agent includes both said barium carbonate and said alkali silicate.
Claim 4
Dependent Claim
22 words
The water soluble core according to claim 1, which further comprises an agent for preventing formation of shrinkage cavities in said casting.
Claim 5
Dependent Claim
14 words
The water soluble core according to claim 3 wherein said agent comprises metallic powder.
Claim 6
Dependent Claim
15 words
The water soluble core according to claim 3 wherein said agent comprises iron oxide red.
Claim 7
Independent Claim
203 words
A method of manufacturing a cast rotor of an induction motor comprising the steps of preparing a plurality of water soluble cores each comprising a mixture consisting essentially of sand in an amount of 100 parts by weight, a first binding agent of potassium carbonate in an amount of 10-50 parts by weight, and a second binding agent selected from the group consisting of barium carbonate in an amount of 1-50 parts by weight and alkali silicate in an amount of 1-15 parts by weight, each of said water soluble cores being provided with a shaft hole and a plurality of conductor slots, interposing said water soluble cores between adjacent laminated core blocks each having a shaft hole and a plurality of slots corresponding to those of said water soluble cores so as to align said water soluble cores and said laminated core blocks to form a laminated assembly, positioning said laminated assembly in a casting mold, pouring electrically conductive molten metal into said casting mold to form conductors, circuit rings, and cooling fins of said cast rotor, and treating with, by water, a cast product taken out from said cast mold thereby to disintegrate said water soluble cores to form ventilation ducts.
Claim 8
Independent Claim
203 words
A method of manufacturing a cast rotor of an induction motor comprising the steps of preparing a plurality of water soluble cores each comprising a mixture consisting essentially of sand in an amount of 100 parts by weight, a first binding agent of potassium carbonate in an amount of 10-50 parts by weight, and a second binding agent selected from the group consisting of barium carbonate in an amount of 1-50 parts by weight and alkali silicate in an amount of 1-15 parts by weight, each of said water soluble cores being provided with a shaft hole and a plurality of conductor slots, interposing said water soluble cores between adjacent laminated core blocks each having a shaft hole and a plurality of slots corresponding to those of said water soluble cores so as to align said water soluble cores and said laminated core blocks to form a laminated assembly, positioning said laminated assembly in a casting mold, pouring electrically conductive molten metal into said casting mold to form conductors, circuit rings, and cooling fins of said cast rotor, and treating with, by water, a cast product taken out from said cast mold thereby to disintegrate said water soluble cores to form ventilation ducts.
Claim 9
Dependent Claim
19 words
The method of claim 6, wherein said second binding agent includes both said barium carbonate and said alkali silicate.
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) | 1987-03-27 | 1987-09-26 | 1988-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-03-27 | 1991-09-26 | 1992-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-03-27 | 1995-09-26 | 1996-03-27 | $7700.00 | Window Closed / Lapsed |