GB372809A - Improvements in or relating to permanent magnets - Google Patents
Improvements in or relating to permanent magnetsInfo
- Publication number
- GB372809A GB372809A GB357231A GB357231A GB372809A GB 372809 A GB372809 A GB 372809A GB 357231 A GB357231 A GB 357231A GB 357231 A GB357231 A GB 357231A GB 372809 A GB372809 A GB 372809A
- Authority
- GB
- United Kingdom
- Prior art keywords
- block
- cobalt
- per cent
- openings
- polepiece
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23K—FEEDING FUEL TO COMBUSTION APPARATUS
- F23K3/00—Feeding or distributing of lump or pulverulent fuel to combustion apparatus
- F23K3/04—Feeding or distributing of lump or pulverulent fuel to combustion apparatus for locomotive boiler furnaces
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R9/00—Transducers of moving-coil, moving-strip, or moving-wire type
- H04R9/02—Details
- H04R9/025—Magnetic circuit
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Magnetic Treatment Devices (AREA)
Abstract
372,809. Loud-speakers &c. ALLEN & CO., Ltd., E. and KERSHAW, H. E., Imperial Steel Works, Sheffield. Feb. 4, 1931, No. 3572. [Class 40 (iv).] A permanent magnet, particularly for moving- coil telephone instruments, comprises a hollow block of cast metal of low permeability (such as cobalt-steel having 1 per cent to 35 per cent cobalt), having an integral wall a and inturned flanges b, d around openings c, e at the ends of the block. An annular polepiece f and a central polepiece g are tightly fitted into the openings c, e, the polepieces being preferably made of metal, such as soft iron, having higher permeability than the magnet body. The ring f forms an air gap around the upper end of the pole g, which gap may be closed at its inner end by an insert k of brass, as shown in Fig. 5. Attachment holes j may be formed in the block.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB357231A GB372809A (en) | 1931-02-04 | 1931-02-04 | Improvements in or relating to permanent magnets |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB357231A GB372809A (en) | 1931-02-04 | 1931-02-04 | Improvements in or relating to permanent magnets |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB372809A true GB372809A (en) | 1932-05-04 |
Family
ID=9760861
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB357231A Expired GB372809A (en) | 1931-02-04 | 1931-02-04 | Improvements in or relating to permanent magnets |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB372809A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2501032A (en) * | 1945-11-30 | 1950-03-21 | Rca Corp | Permanent magnet assembly for electrodynamic loud-speakers |
-
1931
- 1931-02-04 GB GB357231A patent/GB372809A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2501032A (en) * | 1945-11-30 | 1950-03-21 | Rca Corp | Permanent magnet assembly for electrodynamic loud-speakers |
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