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US4610263A Expired / Lapsed US ⏱️ 0.0 years remaining

Pneumatic servo assembly for an electro pneumatic converter

Assignee: Elsag International BV
•
Filing: 1985-07-02
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Granted: 1986-09-09
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Expires: 2005-07-02
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Abstract

Abstract A pneumatic servo assembly (20) is provided for an electro-pneumatic control system (10) having closed loop control of a D.C. motor (12) operated from an error signal (56) developed from an electrical set point signal (4) and a pneumatic feedback signal (44). The feedback signal (44) is made compatible by a pressure transducer (26) monitoring the pressure output signal (22) of the pneumatic servo assembly (20) and establishing an electrical signal indicative thereof which is scaled, zeroed, and amplified by an amplifier unit (46).

Inventors

  • 👤 Christine B. Barnes

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 17:17
CPC Classifications
F; F15; F15C; F15C3/00; F15C3/10; F15C3/14; G; G05; G05D; G05D16/00; G05D16/20; G05D16/2006; G05D16/2013; G05D16/202; Y; Y10; Y10T; Y10T137/00; Y10T137/2278; Y10T137/2409

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 154 words
A pneumatic servo assembly for an electropneumatic control system comprising: a pneumatic backpressure nozzle for providing a pneumatic output signal; a cam shaped movable input restriction for variably blocking the output of said nozzle at substantially the same linear distance therefrom; electric motor means coupled by a shaft to said cam shaped movable input restriction for rotating said cam shaped movable restriction with respect to said nozzle to variable block said nozzle thereby including a nozzle clamp for eliminating end play in the shaft to maintain a substantially constant distance between said nozzle and said cam shaped restriction; a bellows assembly connected to said nozzle to expand and contract in response to the pressure from said nozzle; and said backpressure nozzle and said bellows assembly being attached as a unit to a single pivot point allowing the rotation of both as a unit around said pivot point in response to bellows expansion or contraction.
Claim 2
Dependent Claim 154 words
A pneumatic servo assembly for an electropneumatic control system comprising: a pneumatic backpressure nozzle for providing a pneumatic output signal; a cam shaped movable input restriction for variably blocking the output of said nozzle at substantially the same linear distance therefrom; electric motor means coupled by a shaft to said cam shaped movable input restriction for rotating said cam shaped movable restriction with respect to said nozzle to variable block said nozzle thereby including a nozzle clamp for eliminating end play in the shaft to maintain a substantially constant distance between said nozzle and said cam shaped restriction; a bellows assembly connected to said nozzle to expand and contract in response to the pressure from said nozzle; and said backpressure nozzle and said bellows assembly being attached as a unit to a single pivot point allowing the rotation of both as a unit around said pivot point in response to bellows expansion or contraction.
Claim 3
Dependent Claim 61 words
A pneumatic servo assembly as set forth in claim 1 wherein said nozzle clamp is formed as a single member having one end mounted to said backpressure nozzle with the opposite end in contact with said cam shaped movable restriction on the side opposite said backpressure nozzle thereby taking up any end play in the shaft of said electric motor means.
Claim 4
Dependent Claim 32 words
A pneumatic servo assembly as set forth in claim 1 wherein said bellows assembly includes an adjustable spring connected in parallel with the bellows to adjust the output from the bellows assembly.
Claim 5
Dependent Claim 28 words
A pneumatic servo assembly as set forth in claim 3 wherein said backpressure nozzle is rigidly attached to said bellows assembly to move simultaneously with said bellows assembly.
Claim 6
Dependent Claim 38 words
A pneumatic servo assembly as set forth in claim 3 wherein said motor means is a D.C. motor having a cam assembly connected thereto for variably restricting the pneumatic servo assembly depending upon the position of said cam.
Claim 7
Dependent Claim 36 words
A pneumatic servo assembly as set forth in claim 5 wherein said cam assembly is a flat, substantially spiral-generated plane having a spiral generating center mounted hub for mounting the cam assembly to said motor means.

References Cited (Backward Citations)

US2776669A Cited
US4112960A Cited
US4172464A Cited
US4388942A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-09-08 1990-03-10 1990-09-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-09-08 1994-03-10 1994-09-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-09-08 1998-03-10 1998-09-09 $7700.00 Window Closed / Lapsed

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