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US3902402A Expired / Lapsed US ⏱️ 0.0 years remaining

Electro-hydraulic actuator

Assignee: Vickers Inc
•
Filing: 1974-02-20
•
Granted: 1975-09-02
•
Expires: 1994-02-20
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Abstract

Abstract An actuator comprising a body having a bore, a piston in said bore and having a piston rod. A system pressure gallery or passage is arranged in the body for the application of system pressure to the annular area between the piston and the piston rod, and a chamber is provided in the body for applying pressure to the other end of the piston. The chamber communicates with the system pressure passage through a fixed orifice, and with an exhaust outlet through a variable orifice controlled by a flapper disc arranged to close the end of an outlet tube. The flapper disc has on its opposite face a pressure balancing tube of the same diameter as the outlet tube and working in a bore in the piston. The pressure in this bore is equalized to the exhaust pressure and the flapper disc is controlled by the spring centered armature of a solenoid or force motor.

Inventors

  • 👤 Ronald Bernard Walters

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 21:13
CPC Classifications
F; F15; F15B; F15B9/00; F15B9/02; F15B9/03

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 165 words
An actuator comprising a body having a bore, a piston in said bore and having a piston rod, said body including a system pressure passage arranged for the application of system pressure to the annular area between said piston and said piston rod, and a chamber for applying pressure to the other end of said piston, a fixed orifice through which said chamber communicates with said system pressure passage through said fixed orifice, and a flapper disc arranged to close the end of an outlet tube and provide an exhaust outlet through a variable orifice controlled by said flapper disc, a pressure balancing tube of the same diameter as the outlet tube on the opposite face of said flapper disc, said piston rod having a bore, the pressure balancing tube working in said bore in said piston rod, passageway means for maintaining the pressure in said last mentioned bore equal to the exhaust pressure, a solenoid having a spring centered armature controlling said flapper disc.
Claim 2
Dependent Claim 165 words
An actuator comprising a body having a bore, a piston in said bore and having a piston rod, said body including a system pressure passage arranged for the application of system pressure to the annular area between said piston and said piston rod, and a chamber for applying pressure to the other end of said piston, a fixed orifice through which said chamber communicates with said system pressure passage through said fixed orifice, and a flapper disc arranged to close the end of an outlet tube and provide an exhaust outlet through a variable orifice controlled by said flapper disc, a pressure balancing tube of the same diameter as the outlet tube on the opposite face of said flapper disc, said piston rod having a bore, the pressure balancing tube working in said bore in said piston rod, passageway means for maintaining the pressure in said last mentioned bore equal to the exhaust pressure, a solenoid having a spring centered armature controlling said flapper disc.
Claim 3
Dependent Claim 29 words
An actuator according to claim 1 in which the outlet tube has a sharp edge and the pressure balancing tube has the same outside diameter as said outlet tube.
Claim 4
Dependent Claim 12 words
An actuator according to claim 1 designed for operation with hydraulic fluid.
Claim 5
Dependent Claim 36 words
An actuator according to claim 1 in combination with an electric feed-back circuit whereby the current to the actuator solenoid is controlled in dependence on the position of the piston rod and an external demand signal.

References Cited (Backward Citations)

US1496136A Cited
US3516331A Cited
US3720118A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-09-01 1979-03-03 1979-09-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-09-01 1983-03-03 1983-09-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-09-01 1987-03-03 1987-09-02 $7700.00 Window Closed / Lapsed

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