US4532462A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric actuators
Assignee: Siemens Mobility Ltd
•
Filing: 1984-05-07
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Granted: 1985-07-30
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Expires: 2004-05-07
Abstract
Abstract An electric actuator having an electric motor operable to control the output force generated by a spring system of the actuator on an output member of the actuator; measuring means responsive to a characteristic of the spring system which is indicative of the value of the output force; and an electrical circuit by which operation of the electric motor can be initiated and can be terminated when the measuring means detects the characteristic as being indicative of the output force of a required value.
Inventors
- 👤 Jack Washbourn
- 👤 Howard F. Cogan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:13
CPC Classifications
F; F16; F16D; F16D65/00; F16D65/38; F16D65/40; F16D65/52; F16D65/54; B; B60; B60T; B60T13/00; B60T13/74; B60T13/741; B60T13/743; B60T13/746; B60T17/00; B60T17/08; B60T17/16; B60T8/00; B60T8/18; B60T8/1893; B61; B61H; B61H1/00; F16D55/00; F16D55/02; F16D55/22; F16D55/224; F16D55/2245; F16D65/14; F16D65/28; F16D2065/386; F16D66/00; F16D2066/005; F16D2121/00; F16D2121/18; F16D2121/24; F16D2121/26; F16D2125/00; F16D2125/18; F16D2125/20; F16D2125/34; F16D2125/40; F16D2125/44; F16D2125/46; F16D2125/48; F16D2125/58; F16D2125/582; F16D2127/00; F16D2127/06
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
123 words
An electric actuator comprising an electric motor for controlling the output force generated by a spring system of the actuator on an output member of the actuator; measuring means responsive to the length of a spring of the spring system and comprising two parts, one of said parts carrying a series of switches for controlling the operation of the electric motor, and the other of said parts carrying a cam for sequentially operating said switches; and an electrical circuit for initiating the operation of the electric motor and for, responsive to said measuring means, terminating the operation of said electric motor when the measuring means detects a length of said spring as being indicative of the output force being of a required value.
Claim 2
Dependent Claim
123 words
An electric actuator comprising an electric motor for controlling the output force generated by a spring system of the actuator on an output member of the actuator; measuring means responsive to the length of a spring of the spring system and comprising two parts, one of said parts carrying a series of switches for controlling the operation of the electric motor, and the other of said parts carrying a cam for sequentially operating said switches; and an electrical circuit for initiating the operation of the electric motor and for, responsive to said measuring means, terminating the operation of said electric motor when the measuring means detects a length of said spring as being indicative of the output force being of a required value.
Claim 3
Dependent Claim
31 words
An electric actuator as claimed in claim 1, wherein the electric motor controls the output force generated by the spring system by controlling the length of a spring of the system.
Claim 4
Dependent Claim
52 words
An actuator as claimed in claim 2, wherein the length of the spring is controlled by the electric motor through a pair of threadedly-engaged relatively-rotatable members rotation of one of which is effected by operation of the electric motor and consequential axial movement of the other determines the length of the spring.
Claim 5
Dependent Claim
43 words
An actuator as claimed in claim 2 wherein the spring which is controlled by said electric motor and to which said measuring means is responsive is a power spring which generates the output force and is the sole spring of the spring system.
Claim 6
Dependent Claim
77 words
An actuator as claimed in claim 2 wherein the spring which is controlled by said electric motor is a control spring and the spring to which said measuring means is responsive is a power spring, the control spring being arranged with respect to the power spring such that the force exerted by the control spring is subtracted from the force exerted by the power spring, the residual force exerted by the power spring being the output force.
Claim 7
Dependent Claim
48 words
An actuator as claimed in claim 1, wherein one of the parts is fixed in relation to one end of the spring and the other is adjustable in a direction towards and away from the one of the parts in relation to the other end of the spring.
Claim 8
Dependent Claim
42 words
An actuator as claimed in claim 6, wherein the actuator is a brake actuator of a vehicle and the said other of the parts of the measuring means may be adjustable in said direction in accordance with the load of the vehicle.
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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) | 1988-07-29 | 1989-01-28 | 1989-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-29 | 1993-01-28 | 1993-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-29 | 1997-01-28 | 1997-07-30 | $7700.00 | Window Closed / Lapsed |