Patent US3704770A successfully refreshed from Google Patents.
US3704770A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Adjustable time delay electromagnetic clutch
Assignee: Bendix Corp
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Filing: 1971-09-21
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Granted: 1972-12-05
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Expires: 1991-09-21
Abstract
Abstract An electromagnetic clutch or brake including means for retarding or slowing the engagement and/or release of the armature is shown herein. An additional coil comprising one or more turns of high current capacity wire is included within the magnet body forming an electromagnetic coupling with the main coil in order to impede the generation and/or collapse of the main coil-induced electromagnetic field. A variable resistor or equivalent means is connected in series circuit relationship with the additional coil in order to selectively vary the amount of eddy current permitted to be induced in the additional coil, therefore providing means for regulating the response time of the armature to energization and deenergization of the primary coil. Control means connected in series circuit relationship with the additional coil and variable resistor comprising at least one diode and a switch may also be included so that application of the magnetically retarding coil can be selective and/or unidirectional.
Inventors
- 👤 Glenn S Spencer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:53
CPC Classifications
F; F16; F16D; F16D27/00; F16D27/02; F16D27/04; F16D27/06; F16D48/00; F16D48/06; F16D48/064; F16D2027/002; F16D2027/005; F16D2500/00; F16D2500/10; F16D2500/102; F16D2500/1021; F16D2500/1022; F16D2500/30; F16D2500/316; F16D2500/3166; F16D2500/50; F16D2500/502; F16D2500/50239; F16D2500/52; F16D2500/525; F16D2500/70; F16D2500/704; F16D2500/70402; F16D2500/70418; F16D2500/7042
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
186 words
In combination with an electromagnetic friction device of the type having a plurality of torque transmitting members, a magnet body operatively associated with at least one of said torque transmitting members, an armature operatively associated with at least one other of said torque transmitting members, said armature adapted to move toward and away from said magnet body, first electromagnetic coil means having an electrical power lead operative to generate magnetic flux attracting said armature into clutch engagement when energized and operative to release said armature from engagement when deenergized, and second coil means being in electromagnetic flux circuit relationship with said first electromagnetic coil means such that said first coil means causes an eddy current to be induced in said second coil means whenever energized and whenever deenergized, which eddy currents generate magnetomotive opposition to change in flux levels thereby retarding the magnetic response of the armature both upon engagement and disengagement, wherein the improvement comprises: adjusting means for selectively varying the amount of eddy current permitted to flow in the second coil means, said adjusting means being in circuit relationship with the second coil means.
Claim 2
Dependent Claim
186 words
In combination with an electromagnetic friction device of the type having a plurality of torque transmitting members, a magnet body operatively associated with at least one of said torque transmitting members, an armature operatively associated with at least one other of said torque transmitting members, said armature adapted to move toward and away from said magnet body, first electromagnetic coil means having an electrical power lead operative to generate magnetic flux attracting said armature into clutch engagement when energized and operative to release said armature from engagement when deenergized, and second coil means being in electromagnetic flux circuit relationship with said first electromagnetic coil means such that said first coil means causes an eddy current to be induced in said second coil means whenever energized and whenever deenergized, which eddy currents generate magnetomotive opposition to change in flux levels thereby retarding the magnetic response of the armature both upon engagement and disengagement, wherein the improvement comprises: adjusting means for selectively varying the amount of eddy current permitted to flow in the second coil means, said adjusting means being in circuit relationship with the second coil means.
Claim 3
Dependent Claim
25 words
The combination as claimed in claim 1 wherein said adjusting means comprises variable resistance means connected in series circuit relationship with the second coil means.
Claim 4
Dependent Claim
37 words
The combination as claimed in claim 1 including further switching means in series circuit relationship with the second coil means and the adjusting means, said switching means having an open circuit position, and a closed circuit position.
Claim 5
Dependent Claim
37 words
The combination as claimed in claim 1 including further means for establishing substantially unidirectional eddy current flow in the second coil means, said means being in circuit relationship with the second coil means and the adjusting means.
Claim 6
Dependent Claim
39 words
The combination as claimed in claim 4 wherein said means for establishing substantially unidirectional eddy current flow in the second coil means comprises diode means connected in series circuit relationship with the second coil means and the adjusting means.
Claim 7
Dependent Claim
31 words
The combination as claimed in claim 4 including further switching means connected in series circuit relationship with the means for establishing substantially unidirectional eddy current flow having an open circuit position.
Claim 8
Dependent Claim
42 words
The combination as claimed in claim 4 including further switching means connected in parallel circuit relationship with the means for establishing substantially unidirectional eddy current flow having a closed circuit position which bypasses the means for establishing substantially unidirectional eddy current flow.
Claim 9
Dependent Claim
50 words
The combination as claimed in claim 4 including further switching means connected in series circuit relationship with the means for establishing substantially unidirectional eddy current flow having a position for selectively varying the amount of eddy current flow in the second coil means when the first coil means is energized.
Claim 10
Dependent Claim
50 words
The combination as claimed in claim 4 including further switching means connected in series circuit relationship with the means for establishing substantially unidirectional eddy current flow having a position for selectively varying the amount of eddy current flow in the second coil means when the first coil means is deenergized.
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) | 1975-12-05 | 1976-06-05 | 1976-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-12-05 | 1980-06-05 | 1980-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-12-05 | 1984-06-05 | 1984-12-05 | $7700.00 | Window Closed / Lapsed |