Patent US3564442A successfully refreshed from Google Patents.
Patent US3742407A successfully refreshed from Google Patents.
US3742407A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solenoid device
Assignee: National Research Development Corp UK
•
Filing: 1971-10-06
•
Granted: 1973-06-26
•
Expires: 1991-10-06
Abstract
Abstract A solenoid device capable, by variation of coil current, of holding the core at positions intermediate the ends of its working range of movement. A force matching device, for example a resilient pad mounted on the coil and lying in the path of the core, opposes the approach of the core to the coil. The characteristics of this device are chosen to match the increasing electromagnetic force of attraction between coil and core as they approach and as coil current rises. The solenoid device may be used in an electromagnetic control valve in which the valve setting is required to be proportionate to the input signal.
Inventors
- 👤 K Cardew
- 👤 S Petty
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:26
CPC Classifications
H; H01; H01F; H01F7/00; H01F7/06; H01F7/08; H01F7/088; H01F7/13; H01F7/16; H01F7/1607
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
140 words
A solenoid device comprising: a coil and a core, said core being mounted for a working range of movement towards and away from said coil, said coil being adapted to generate a first electromagnetic force to attract said core, said first force gradually increasing according to a first predetermined pattern as coil current increases and the separation of the coil and core decreases, a force matching device, said device being adapted to generate a second force opposing the mutual approach of the coil and core, said second force gradually increasing according to a second predetermined pattern as the separation of the coil and core decreases, and wherein said first and second patterns are matched, whereby said coil may hold said core at positions between the extreme ends of said working range of movement, said positions being dependent upon coil current.
Claim 2
Dependent Claim
140 words
A solenoid device comprising: a coil and a core, said core being mounted for a working range of movement towards and away from said coil, said coil being adapted to generate a first electromagnetic force to attract said core, said first force gradually increasing according to a first predetermined pattern as coil current increases and the separation of the coil and core decreases, a force matching device, said device being adapted to generate a second force opposing the mutual approach of the coil and core, said second force gradually increasing according to a second predetermined pattern as the separation of the coil and core decreases, and wherein said first and second patterns are matched, whereby said coil may hold said core at positions between the extreme ends of said working range of movement, said positions being dependent upon coil current.
Claim 3
Dependent Claim
35 words
A solenoid device according to claim 1 wherein the two said patterns are such that unit incremental change in coil current produces an unvarying unit movement of the core within its working range of movement.
Claim 4
Dependent Claim
48 words
A solenoid device according to claim 1, in which the force matching device is elastic, in which this device is fixed relative to one of said coil and core members, and in which the other of said members distorts the device upon relative movement of the two members.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-25 | 1976-12-25 | 1977-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-25 | 1980-12-25 | 1981-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-25 | 1984-12-25 | 1985-06-26 | $7700.00 | Window Closed / Lapsed |