EP 1797338 B1 20080820 - TWO-STAGE SERVO-VALVE
Title (en)
TWO-STAGE SERVO-VALVE
Title (de)
ZWEISTUFIGES SERVOVENTIL
Title (fr)
SERVOVALVE A DEUX ETAGES
Publication
Application
Priority
- EP 2005055030 W 20051005
- DE 102004048689 A 20041006
Abstract (en)
[origin: WO2006037793A1] A two-stage servo-valve (1) has a first stage (2) in which four flow resistances (3-6) are arranged in a bridge circuit. At least one of the flow resistances (5, 6) is variable, and two opposite switching points (8, 9) of the bridge circuit are connected to an air inlet (P2) and to an air outlet (E), respectively. A differential pressure of variable size and sign is provided between the two other switching points (10, 11). The servo-valve (1) also has a second stage (12) in which a control piston (13) which can be actuated by the differential pressure is arranged and controls a three-way valve (16). In order to enable the current position of a process valve driven by the servo-valve to be maintained by the most simple means in the event of a power failure, the switching points (10, 11) which provide the differential pressure are interconnected by a magnetic valve (17) which is closed in the driven state and open in the unconnected state, thus pneumatically interconnecting the switching points (10, 11).
IPC 8 full level
F15B 11/00 (2006.01); F15B 13/02 (2006.01); F15B 13/042 (2006.01); F15B 21/00 (2006.01); F15C 3/00 (2006.01); F16K 31/02 (2006.01)
CPC (source: EP US)
F15B 11/006 (2013.01 - EP US); F15B 13/042 (2013.01 - EP US); F15B 2211/30525 (2013.01 - EP US); F15B 2211/3111 (2013.01 - EP US); F15B 2211/3144 (2013.01 - EP US); F15B 2211/31576 (2013.01 - EP US); F15B 2211/329 (2013.01 - EP US); F15B 2211/355 (2013.01 - EP US); F15B 2211/40507 (2013.01 - EP US); F15B 2211/40515 (2013.01 - EP US); F15B 2211/50563 (2013.01 - EP US); F15B 2211/5151 (2013.01 - EP US); F15B 2211/526 (2013.01 - EP US); F15B 2211/575 (2013.01 - EP US); F15B 2211/8633 (2013.01 - EP US); Y10T 137/86582 (2015.04 - EP US); Y10T 137/8659 (2015.04 - EP US); Y10T 137/86614 (2015.04 - EP US)
Designated contracting state (EPC)
DE FR GB
DOCDB simple family (publication)
DE 102004048689 B3 20051020; CN 100526659 C 20090812; CN 101035990 A 20070912; DE 502005005145 D1 20081002; EP 1797338 A1 20070620; EP 1797338 B1 20080820; US 2008066814 A1 20080320; US 7757714 B2 20100720; WO 2006037793 A1 20060413
DOCDB simple family (application)
DE 102004048689 A 20041006; CN 200580033764 A 20051005; DE 502005005145 T 20051005; EP 05797287 A 20051005; EP 2005055030 W 20051005; US 66474005 A 20051005