US4035751A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for inducing an electrical voltage
Assignee: Individual
•
Filing: 1975-05-27
•
Granted: 1977-07-12
•
Expires: 1995-05-27
Abstract
Abstract A device for inducing an electrical voltage comprises primary and secondary windings wound round a core. The core has a first part responsive to high frequencies and a second part responsive to low frequencies. The axial length of the first part does not exceed the axial length of the second part, but exceeds the axial length of primary and secondary windings.
Inventors
- 👤 Ainslie Walthew
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:04
CPC Classifications
H; H01; H01F; H01F27/00; H01F27/24; H01F38/00; H01F38/12; H01F2038/122; H01F2038/125
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
122 words
An ignition coil for a spark ignition internal combustion engine comprising a housing, an open linear core disposed in said housing, primary and secondary inductance windings wound round said core, said core having a first part responsive to higher frequencies and a second part responsive to very low frequencies, said second part of said core having an axial length not exceeding the axial length of the first part of said core but exceeding the axial length of the primary and secondary inductance windings wound round the core, at least one of said parts of said core being a ferrite, and a body of oil in said housing in which said core and windings are immersed, said housing having a vacuum maintained therein.
Claim 2
Dependent Claim
122 words
An ignition coil for a spark ignition internal combustion engine comprising a housing, an open linear core disposed in said housing, primary and secondary inductance windings wound round said core, said core having a first part responsive to higher frequencies and a second part responsive to very low frequencies, said second part of said core having an axial length not exceeding the axial length of the first part of said core but exceeding the axial length of the primary and secondary inductance windings wound round the core, at least one of said parts of said core being a ferrite, and a body of oil in said housing in which said core and windings are immersed, said housing having a vacuum maintained therein.
Claim 3
Dependent Claim
24 words
A coil as claimed in claim 1, in which the core comprises a ferrite matrix tube filled with a plurality of malleable iron rods.
Claim 4
Dependent Claim
26 words
A coil as claimed in claim 1, in which the core comprises a solid ferrite matrix rod with a plurality of malleable iron rods surrounding it.
Claim 5
Dependent Claim
30 words
A coil as claimed in claim 1, in which the core comprises a solid ferrite matrix rod disposed in a solid tube of a ferrite matrix of a different type.
Claim 6
Dependent Claim
24 words
A coil as claimed in claim 1, in which the core comprises two ferrite matrix rods surrounded by a plurality of malleable iron rods.
Claim 7
Dependent Claim
52 words
A coil as claimed in claim 1, in which the core comprises a ferrite rod, a plurality of iron rods surrounding the ferrite rod, a ferrite tube surrounding the iron rods and a further ferrite tube surrounding the first ferrite tube, the ferrite of the rod and tubes being of different types.
Claim 8
Dependent Claim
21 words
A coil as claimed in claim 1, in which the core is housed in a tube forming part of a former.
Claim 9
Dependent Claim
17 words
A coil as claimed in claim 7, in which the tube is made of synthetic plastics material.
Claim 10
Dependent Claim
24 words
A coil as claimed in claim 7, in which the tube is externally splined to provide axially extending channels for the passage of coolant.
Claim 11
Dependent Claim
29 words
A coil as claimed in claim 7, in which the secondary inductance winding is wound on the former and the primary inductance is wound over the secondary inductance winding.
Claim 12
Dependent Claim
37 words
A coil as claimed in claim 1, in which adjacent layers of the primary inductance winding are separated by circumferentially extending layers of ribbed flexible synthetic plastics material, the ribs defining channels for the circulating of coolant.
Claim 13
Dependent Claim
23 words
A coil as claimed in claim 9, in which the channels are such as to enable the coolant to circulate by capillary action.
Claim 14
Dependent Claim
21 words
A coil as claimed in claim 7, in which the former comprises end cheeks disposed at opposite axial ends respectively thereof.
Claim 15
Dependent Claim
21 words
A coil as claimed in claim 13, in which the end cheeks are separate from the tubular part of the former.
Claim 16
Dependent Claim
59 words
A coil device as claimed in claim 14, in which each end cheek comprises two substantially semi-circular metal plates encapsulated in synthetic plastics material and each plate comprises one or more lugs extending from the periphery out of the synthetic plastics material, and defines a substantially semi-circular recess which receives one end of the tubular part of the former.
Claim 17
Dependent Claim
39 words
A device as claimed in claim 15, in which two half shells surround the primary and secondary inductance windings, each half shell having one or more axial slits to receive respective lugs off corresponding plates of the end cheeks.
Claim 18
Dependent Claim
27 words
A coil as claimed in claim 16, in which the end plates are made of a material selected from a group consisting of Stalloy and malleable iron.
Claim 19
Dependent Claim
27 words
A coil as claimed in claim 16, in which the half shells are made of a material selected from a group consisting of Stalloy and malleable iron.
Claim 20
Dependent Claim
33 words
A coil as claimed in claim 1, in which the connectors to the primary inductance winding are disposed at the opposite axial end of the core to the connector for the secondary inductance.
Claim 21
Dependent Claim
25 words
A coil as claimed in claim 1, in which the connector to the secondary winding is phosphor bronze spring connected to a onepiece brass insert.
Claim 22
Dependent Claim
29 words
A coil as claimed in claim 1, in which the connector to the secondary winding is a beryllium-copper spring connected to a plated brass oil and vacuum securing screw.
Claim 23
Dependent Claim
34 words
A coil as claimed in claim 1, in which the secondary inductance winding comprises an insulated conductor interleaved with two layers of varnish impregnated glass fibre craft paper between adjacent layers of the winding.
Claim 24
Dependent Claim
18 words
A coil as claimed in claim 1, in which said housing for the inductance windings synthetic plastics material.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-11 | 1981-01-10 | 1981-07-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-11 | 1985-01-10 | 1985-07-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-11 | 1989-01-10 | 1989-07-12 | $7700.00 | Window Closed / Lapsed |