47 0 532KB
Introduction into the Mechanical FeedBack (MFB) Servovalves
Assembly of MFB Principle assembly of the a Mechanical FeedBack Valve 1
2
1
Connector
2
Pilotstage - Torque Motor
3
Feedback wire
4
Bushing
5
Spool
6
Orifice
7
Valve body
8
Filterplate (In P for Pilotstage)
9
Mounting manifold
3
4
5
6
6
9 MOOG Training
8
7
Page 2
Assembly / Torque Motor
Electro Mechanical Amplifier
Hydraulic Amplifier Nozzle
Flapper
Feedback Wire
This valve type is also called:
Nozzle Flapper Stage MOOG Training
Page 3
Assembly / Torque Motor Function of Electro-Mechanical Amplifier
Ø Charged permanent magnets polarize the pole pieces Ø DC current in coils causes increased force in diagonally opposite air gaps N
N
N
S
S
MOOG Training
S
coil flux
Ø Magnetic charge level sets magnitude of decentering force gradient on armature
Page 4
Assembly / Torque Motor Function of the Hydraulic Amplifier
FROM SPOOL END
RETURN ORIFICE
Ø
Ø
Armature and flapper rigidly joined and supported by thin-wall flexure sleeve.
Ø
Ø Fluid continuously flows from pressure Ps, through both inlet orifices, via the nozzles into the flapper chamber and finally through the drain orifice to tank T.
MOOG Training
TO SPOOL END
Rotary motion of armature / flapper throttles flow through one nozzle or the other This diverts flow to one end of the spool
Page 5
Function MFB Valve
Null Position: Null current is supplied to the coils of the Torque Motor and the motor stand in his middle position. The gabs between the right-and-left nozzle are the same. Due to the same gabs the pressure on both spool ends is symmetric. The Spool of the main stage is also located in middle position. Port A and B are closed MOOG Training
Page 6
Function MFB Valve
bent feedback wire
Movement of spool
Operating: If an input signal is applied the Torque Motor will pull out, therefore the gab between the right-and-left nozzle will change and a different pressure will arise at both sites of the spool. Due to the Delta P on the spool ends the spool will move. Thus the feedback wire will bent according to the displacement of a spool. The Ports P to A and the Port B to T will open and oil will flow through the BSA of the main stage. MOOG Training
Page 7
Function MFB Valve
Position reached: As feedback torque becomes equal to torque from the magnetic forces, the Flapper moves back to centered position. Then the gab between the Nozzles and the Flapper and the pressure at both spool ends will be the same. The spool stops at the position where the torque of the feedback spring is alike the torque induced by the applied current to the coil. MOOG Training
Page 8
MFB - Advantages ¤ ¤ ¤ ¤ ¤ ¤ ¤ ¤ ¤ ¤ ¤
MOOG Training
2 stage design with dry torque motor Low friction double nozzle pilotstage High spool control forces High dynamics Replaceable pilot stage filter Rugged and long-life design High resolution, low hysterese Completely set up at the factory Optional fifth port for separate pilot supply Low power consumption Precise axis cut Page 9
MFB - Family
77 Series
72 Series
G631 Series
D630 Series
78 Series
G761 Series MOOG Training
0062 Series Page 10
MFB - Comparison Manifold
Max Pressure
Flow Rate
Port P,X,A,B
at 70 bar Delta P
D062
ISO 10372-04-04-0-92
3000 psi / 210 bar
10 l/min -> 40 l/min
G631
ISO 4401-05-05-0-94
4500 psi / 315 bar
5 l/min -> 75 l/min
072
ISO 10372-06-05-0-92
3000 psi / 210 bar
95 l/min -> 230 L/min
D630
ISO 10372-04-04-0-92
4000 psi / 280 bar
05 l/min -> 40 l/min
G773
Moog Norm
3000 psi / 210 bar
57 l/min
G772
ISO 10372-03-03-0-92
3000 psi / 210 bar
19 l/min -> 38 l/min
G771
Moog Norm
3000 psi / 210 bar
4 l/min -> 10 l/min
G761
ISO 10372-04-04-0-92
4500 psi / 315 bar
4 l/min -> 63 l/min Standard katalog values
MOOG Training
Page 11
MFB - Comparison Rated Flow *1 230
072
95 l/min 80
G631*4 G761-S63 G773
40
D062*4
G772
D630-S *3
G761-H38 D630-S *3
G771
5 50
100
*1) Q at 70 bar Delta P. *3) 280 bar and 90° Phaseangle and +/- 40% Sig MOOG Training
150
G761-H19 G761-H10 G761-H04
200 Dynamic Hz *2
*2) 210 bar and 90° Phaseangle and +/- 40% Sig *4) 210 bar and 90° Phaseangle and +/- 25% Sig Page 12
MFB - Comparison Typical dynamic characteristics (standard valves) *2
D062
*2
G631 072G773 G772 G771
*3 D630
G761
100 200 Hz at 90° Phaseangle *1 *1) At 210 bar ; 90° Phaseangle ; +/- 40% Signal *3) At 280 bar ; -3 dBAmplitude ; +/- 40% Signal MOOG Training
200 100 Hz at -3db Amplitude *3
*2) At 210 bar ; 90° Phaseangel ;+/- 25 Signal *4) At 210 bar ; 90° Phaseangel ;+/- 25 Signal Page 13
MFB - Comparison Rated Flow at 70 bar Delta P D062 G631 072G773 G772 G771 D630 G761
15
MOOG Training
30
45
60
75 l/min
90
160
230 l/min
Page 14
MFB - Applications
MOOG Training
62 / D062 D631
Low performance position control ddd
D630
Pilotstage for Proportional valves
G760 / G761 G77X
Material Testing, Turbine, Simulators Turbine
78
Wood, Old flight simulators
72
Steel Mills, Mat. Testing
Page 15
MFB - Interface
Hydraulic Interface 4-Port valve / ISO 10372 / ISO 4401
Standard Manifold
Manifold example
Detailed information see individual catalogs
MOOG Training
Page 16
MFB - Interface
Hydraulic Interface 5-Port valve / ISO 10372 / ISO 4401 External Pilot supply
Manifold example
Detailed information see individual catalogs
MOOG Training
Use of External 5 Port ¤ The Pilotstage (Torque Motor) can be separatly supplied from the mainstage. Advantages of the fifth Port ¤ Increasing the danymic and the spool control force due to a higher pilotspressure. ¤
Additional filtration for Piltostage possible.
¤
For Failsafe condition the Pilotstage can be controlled by an external solinoid valve. Page 17
MFB - Interface
Electrical Interface 4 Pin Valve Connectors e.g.: 4 Pin MIL-C-5015/14S-2S
Coils wire leads are available at the connector allowing for single, series, or parallel connections
Valve
Valve
Valve
Co nnect or
Co nnect or
Co nnect or
Detailed information see individual catalogs MOOG Training
Page 18
MFB - Family
77 Series
72 Series
G631 Series
D630 Series
78 Series
G761 Series MOOG Training
0062 Series Page 19