US3078863A - Electro hydraulic servo device - Google Patents

Electro hydraulic servo device Download PDF

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Publication number
US3078863A
US3078863A US65260857A US3078863A US 3078863 A US3078863 A US 3078863A US 65260857 A US65260857 A US 65260857A US 3078863 A US3078863 A US 3078863A
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Prior art keywords
armature
valve
fluid
collar
nozzles
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Martin P Wolpin
Johannes G Goerner
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Bell Aerospace Corp
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Bell Aerospace Corp
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/042—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure
    • F15B13/043—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure with electrically-controlled pilot valves
    • F15B13/0438—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure with electrically-controlled pilot valves the pilot valves being of the nozzle-flapper type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K31/00—Actuating devices; Operating means; Releasing devices
    • F16K31/12—Actuating devices; Operating means; Releasing devices actuated by fluid
    • F16K31/42—Actuating devices; Operating means; Releasing devices actuated by fluid by means of electrically-actuated members in the supply or discharge conduits of the fluid motor
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/2278—Pressure modulating relays or followers

Definitions

  • This invention relates in generalto servo mechanisms, and-in 'particular to electro hydraulic servo valves, such as shown in copending application, Serial No. 511,088 tiled May V25,- 1955, by MartinP. Wolpin,fet al. Furthermore, this invention comprises improvements over mechanisms as shown for example in U.S. Patents 2,655,939; 2,655,940; 2,625,136; 2,767,689; Vand British Patent 712,329'of 1954.
  • An object lof the present invention is to provide ⁇ a valve of the aforesaid vtype in which the electrical parts of the valve are sealed ot in improved manner from the fluid containing chambers thereof.
  • Another object is to provide ⁇ an improved valve as aforesaid wherein the armature is mounted and stabilized in its fulcruming operation in improved manner.
  • Another object is to provide an improved device as aforesaid wherein the armature element is stabilized against acceleration forces.
  • Another object of the invention is to provide an improvide valve as aforesaid which may be economically made by standard type production methods.
  • Another object is to provide a valve as aforesaid having relatively few parts.
  • FIG. l is a vertical sectional view, somewhat in diagram, of one form of the device of the invention.
  • FIG. 2 is a sectional view taken on line II--II of FIG. 1.
  • one form of the device of the invention may be employed in conjunction with an hydraulic valve mechanism shown to comprise a body having therewithin a valve spool 25 and oil passageways (not shown) as disclosed for example in FIG. l of copending U.S. patent application Serial No. 511,088 tiled May 25, 1955, by Martin P. Wolpin et al.; the fluid passageways exiting from the Valve body 15 as indicated at 16, 18, 20, 22, 30, 32 and 34.
  • an actuator comprising cylinder 24, piston 26, and connecting rod 28, or the like, may be operatively coupled to the fluid conduits 20, 22 so that the latter open into the cylinder 24 at opposite sides of the piston.
  • the port 16 constitutes the pressured fluid inlet of the valve mechanism, while the port 18 constitutes the return line; and thus it will be understood that shifting of the valve spool 25 within the body 15, as controlled by the electroc-magnetic component of the device as will be explained hereinafter, will cause the actuator 2S to be displaced in accord with the purpose of the mechanism.
  • the fluid passageways 30, 32 normally supply oil under equal pressures from chambers at opposite ends of the valve spool 25, to corresponding opposed nozzles 40, 42 mounted as in a body block 44 and arranged to jet oil against opposite sides of a flattened end portion 46 of the armature S0 of the electromagnetic component of the device.
  • the armature end portion 46 is disposed within an oil chamber 52 formed in body block 44, and chamber 5.2 communicates with port 34 which leads to the oil return conduit 13.
  • armatureend-portion46- is normally centered between the nozzles 4t), 42 and isslightly spaced equally inv relation therefrom'whereby constant ows ofoil may pass through the-nozzles4tl,-4 ⁇ 2 from the chambersl at opposite ends of the'valve spool against thev armaturel part 46 and thence throughthe return conduit.
  • any displacement of the armature part relative to the -noz'zles 40, 42 will differentially throttle the latter, and thereby upset the previous pressure equilibrium at opposite ends of the valve spool '25.
  • valve spool This will cause the valve spool to shift with consequent adjustment of thevalve action controlling iiow of oil from the inlet 16 throughactuator parts 20, 22; thereby energizing the actuator 28 consonant with the degree of detiection of the armature part 46 from -its normalcentralized position.
  • such resilient mounting may beV providediby means of a hat-shaped housing 56'forme ⁇ d of spring material mounted in liuid sealed relation to and embracing themidportion of the armature bar 50; the bottom skirt portion of the housing 5.6 being welded or other-wiselsuitably fixed in fluid-sealed relation as indicated at 53 to a base plate 66 which is bolted as indicated at 62 to the body block 44.
  • the joints between the housing 56 and the armature 50 and the base plate 60 are of iluid-pressure-sealed type, and a pressure seal as indicated at 64 is preferably employed to seal the joint between the plate 60 and the body member 44.
  • the armature device is conveniently constructed of an upper section 50 and a lower section 65 carrying the llat end portion 46; the sections 50, 65 being telescopically interttted to provide the unitary assembly.
  • electro-magnet coils 68 are mounted within an enclosing housing 72 at opposite sides of the armature, and are arranged to be differentially energized in response to any control or error or other input signal, as is well understood in the art.
  • Permanent magnets as indicated at 74, 76 may also be employed at opposite sides of the armature for normally biasing the armature to centralized position.
  • rocking of the armature for differential throttling of the nozzles 40, 42 will be accomplished in response to a signal and to a degree commensurate with the strength of the signal to the coils 68, 70, as they may overcome the balanced forces of the permanent magnets and as controlled by the spring rate of the resilient housing 56.
  • the housing 56 functions simultaneously to normally spring-bias the armature towards nozzle-centered position and controls oscillations thereof and returns it to central position upon lapse of any biasing signal; while at the same time it fluid seals the coils 68, 76 from contamination by oil from the nozzle chamber of the mechanism.
  • the upper end of the support tube 56 is stabilized in a novel manner, such as by straps Sii-S0 extending diametrically from the upper end of the tube 56 into fixed connections with opposite sides of the base member 82 which may be either integral with the base member 44 or rigidly connected thereto to assist in mounting the components of the mechanism.
  • the straps 80-86 extend in the plane of oscillation of the armature 50i-65, and thus they lirmly maintain the center of oscillation of the armature always at the same elevation; that is, in line with the straps 862-66.
  • the armature in spite of varying net magnetic and hydraulic forces on the armature, the armature always pivots about the same center; and thus it is practicable to construct the device to accept lateral forces with uniformly predictable results. None the less, because the straps 80--86 are flexible they provide no interference with oscillation of the armature.
  • a pilot valve for control of a pair of oppositely arranged fluid pressure nozzles said valve comprising a body, a resilient collar carried by said body in uid-sealed relation therewith, a llapper valve assembly comprising an armature extending through and carried by said collar in fluid-sealed relation therewith and formed with a tip portion disposed between said nozzles for oscillating movement relative thereto, restraint means extending from said body to said collar to stabilize the latter against lateral displacement and thereby maintain a xed level of fulcruming of said armature relative to said body, and motor means operable to impose biasing forces upon said armature whereby operation of said motor means will cause the dapper valve assembly to rock while elastically deforming said collar.
  • a pilot valve for control of a servo valve comprising a body, oppositely arranged tluid pressure nozzles carried by said body, a resilient collar carried by said body in duid-sealed relation therewith adjacent one end of said collar, an armature assembly formed of magnetio-responsive material extending through and carried by the opposite end of said collar in duid-sealed relation therewith and formed with a flat tip portion disposed between said nozzles for oscillating movement relative thereto, flexible strap means extending from said body in the plane of oscillation of said armature and connected to said collar at a point spaced from said one end thereof to stabilize a portion thereof against lateral displacement and to thereby establish a fixed level of fulcruming of said armature relative to said body, said armature extending outwardly from said collar and disposed between the poles of an electromagnet, whereby variable signals received by said electromagnet will cause the armature assembly to rock within said collar for corresponding variable throttling of said nozzles.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Servomotors (AREA)

Description

Feb. 26, 1963 M. P. woLPlN ETAL 3,078,863
ELECTRO HYDRAULIC sERvo DEvIcE Filed April 12, 1957 INVENTORS MARTIN P. WOLPIN JOHANNES G. GOERNER BY @244g M M4 TTH/VEYS 3,078,863 Patented Feb. 26, 1963 ,3,678,863 ELECTRO yHYDRAULIC SERV() DEVICE Martin P. Wolpin, Tonawanda, and Johannes G.Goer
ner, Snyder, N.Y., assignors, by mesne assignments, to
Bell Aerospace Corporation, Wheattield, N.Y., a co1'- pnration of Delaware Filed Apr. 12, 1957, Ser. No. 652,608 -2Claims. v(Cl. 137-82) This invention relates in generalto servo mechanisms, and-in 'particular to electro hydraulic servo valves, such as shown in copending application, Serial No. 511,088 tiled May V25,- 1955, by MartinP. Wolpin,fet al. Furthermore, this invention comprises improvements over mechanisms as shown for example in U.S. Patents 2,655,939; 2,655,940; 2,625,136; 2,767,689; Vand British Patent 712,329'of 1954.
An object lof the present invention is to provide `a valve of the aforesaid vtype in which the electrical parts of the valve are sealed ot in improved manner from the fluid containing chambers thereof.
Another object is to provide `an improved valve as aforesaid wherein the armature is mounted and stabilized in its fulcruming operation in improved manner.
Another object is to provide an improved device as aforesaid wherein the armature element is stabilized against acceleration forces.
Another object of the invention is to provide an improvide valve as aforesaid which may be economically made by standard type production methods.
Another object is to provide a valve as aforesaid having relatively few parts.
Other objects and advantages of the invention will be apparent from the following specification wherein one form of the invention is shown in the accompanying drawings, of which:
FIG. l is a vertical sectional view, somewhat in diagram, of one form of the device of the invention; and
FIG. 2 is a sectional view taken on line II--II of FIG. 1.
As shown in the drawing, one form of the device of the invention may be employed in conjunction with an hydraulic valve mechanism shown to comprise a body having therewithin a valve spool 25 and oil passageways (not shown) as disclosed for example in FIG. l of copending U.S. patent application Serial No. 511,088 tiled May 25, 1955, by Martin P. Wolpin et al.; the fluid passageways exiting from the Valve body 15 as indicated at 16, 18, 20, 22, 30, 32 and 34. As in the prior application referred to, an actuator comprising cylinder 24, piston 26, and connecting rod 28, or the like, may be operatively coupled to the fluid conduits 20, 22 so that the latter open into the cylinder 24 at opposite sides of the piston. The port 16 constitutes the pressured fluid inlet of the valve mechanism, while the port 18 constitutes the return line; and thus it will be understood that shifting of the valve spool 25 within the body 15, as controlled by the electroc-magnetic component of the device as will be explained hereinafter, will cause the actuator 2S to be displaced in accord with the purpose of the mechanism.
As in the case of the copending patent application, the fluid passageways 30, 32 normally supply oil under equal pressures from chambers at opposite ends of the valve spool 25, to corresponding opposed nozzles 40, 42 mounted as in a body block 44 and arranged to jet oil against opposite sides of a flattened end portion 46 of the armature S0 of the electromagnetic component of the device. The armature end portion 46 is disposed within an oil chamber 52 formed in body block 44, and chamber 5.2 communicates with port 34 which leads to the oil return conduit 13. The
armatureend-portion46-is normally centered between the nozzles 4t), 42 and isslightly spaced equally inv relation therefrom'whereby constant ows ofoil may pass through the-nozzles4tl,-4`2 from the chambersl at opposite ends of the'valve spool against thev armaturel part 46 and thence throughthe return conduit. However, any displacement of the armature part relative to the - noz'zles 40, 42 will differentially throttle the latter, and thereby upset the previous pressure equilibrium at opposite ends of the valve spool '25. This will cause the valve spool to shift with consequent adjustment of thevalve action controlling iiow of oil from the inlet 16 throughactuator parts 20, 22; thereby energizing the actuator 28 consonant with the degree of detiection of the armature part 46 from -its normalcentralized position.
To provide Yfor such operation of the armature it is resiliently'mounted relative to the body portions'44, 54; as shown inFlG. l such resilient mounting may beV providediby means of a hat-shaped housing 56'forme`d of spring material mounted in liuid sealed relation to and embracing themidportion of the armature bar 50; the bottom skirt portion of the housing 5.6 being welded or other-wiselsuitably fixed in fluid-sealed relation as indicated at 53 to a base plate 66 which is bolted as indicated at 62 to the body block 44. Thus, the joints between the housing 56 and the armature 50 and the base plate 60 are of iluid-pressure-sealed type, and a pressure seal as indicated at 64 is preferably employed to seal the joint between the plate 60 and the body member 44. As shown in FIG. 1, the armature device is conveniently constructed of an upper section 50 and a lower section 65 carrying the llat end portion 46; the sections 50, 65 being telescopically interttted to provide the unitary assembly.
To cause the armature to rock upon the housing 56 as its fulcrum, electro-magnet coils 68, are mounted within an enclosing housing 72 at opposite sides of the armature, and are arranged to be differentially energized in response to any control or error or other input signal, as is well understood in the art. Permanent magnets as indicated at 74, 76 may also be employed at opposite sides of the armature for normally biasing the armature to centralized position. Thus, rocking of the armature for differential throttling of the nozzles 40, 42 will be accomplished in response to a signal and to a degree commensurate with the strength of the signal to the coils 68, 70, as they may overcome the balanced forces of the permanent magnets and as controlled by the spring rate of the resilient housing 56. Thus, the housing 56 functions simultaneously to normally spring-bias the armature towards nozzle-centered position and controls oscillations thereof and returns it to central position upon lapse of any biasing signal; while at the same time it fluid seals the coils 68, 76 from contamination by oil from the nozzle chamber of the mechanism.
It is another particular feature of the present invention that the upper end of the support tube 56 is stabilized in a novel manner, such as by straps Sii-S0 extending diametrically from the upper end of the tube 56 into fixed connections with opposite sides of the base member 82 which may be either integral with the base member 44 or rigidly connected thereto to assist in mounting the components of the mechanism. The straps 80-86 extend in the plane of oscillation of the armature 50i-65, and thus they lirmly maintain the center of oscillation of the armature always at the same elevation; that is, in line with the straps 862-66. Hence, in spite of varying net magnetic and hydraulic forces on the armature, the armature always pivots about the same center; and thus it is practicable to construct the device to accept lateral forces with uniformly predictable results. None the less, because the straps 80--86 are flexible they provide no interference with oscillation of the armature.
What is claimed is:
1. A pilot valve for control of a pair of oppositely arranged fluid pressure nozzles, said valve comprising a body, a resilient collar carried by said body in uid-sealed relation therewith, a llapper valve assembly comprising an armature extending through and carried by said collar in fluid-sealed relation therewith and formed with a tip portion disposed between said nozzles for oscillating movement relative thereto, restraint means extending from said body to said collar to stabilize the latter against lateral displacement and thereby maintain a xed level of fulcruming of said armature relative to said body, and motor means operable to impose biasing forces upon said armature whereby operation of said motor means will cause the dapper valve assembly to rock while elastically deforming said collar.
2. A pilot valve for control of a servo valve comprising a body, oppositely arranged tluid pressure nozzles carried by said body, a resilient collar carried by said body in duid-sealed relation therewith adjacent one end of said collar, an armature assembly formed of magnetio-responsive material extending through and carried by the opposite end of said collar in duid-sealed relation therewith and formed with a flat tip portion disposed between said nozzles for oscillating movement relative thereto, flexible strap means extending from said body in the plane of oscillation of said armature and connected to said collar at a point spaced from said one end thereof to stabilize a portion thereof against lateral displacement and to thereby establish a fixed level of fulcruming of said armature relative to said body, said armature extending outwardly from said collar and disposed between the poles of an electromagnet, whereby variable signals received by said electromagnet will cause the armature assembly to rock within said collar for corresponding variable throttling of said nozzles.
References Cited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES Control Engineering, McGraw-Hill Publication, N.Y.C., May 1955, page 21, Moog Advertisement.

Claims (1)

1. A PILOT VALVE FOR CONTROL OF A PAIR OF OPPOSITELY ARRANGED FLUID PRESSURE NOZZLES, SAID VALVE COMPRISING A BODY, A RESILIENT COLLAR CARRIED BY SAID BODY IN FLUID-SEALED RELATION THEREWITH, A FLAPPER VALVE ASSEMBLY COMPRISING AN ARMATURE EXTENDING THROUGH AND CARRIED BY SAID COLLAR IN FLUID-SEALED RELATION THEREWITH AND FORMED WITH A TIP PORTION DISPOSED BETWEEN SAID NOZZLES FOR OSCILLATING MOVEMENT RELATIVE THERETO, RESTRAINT MEANS EXTENDING FROM SAID
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3137309A (en) * 1962-04-30 1964-06-16 Link Division General Prec Inc Frictionless zero spring rate seal
US3233623A (en) * 1962-12-04 1966-02-08 Bell Aerospace Corp Multi-input control mechanism for hydraulic servo valve
FR2586870A1 (en) * 1985-09-04 1987-03-06 Applic Mach Motrices TORQUE MOTOR WITH HYDRAULIC POTENTIOMETER FOR SERVO-DISTRIBUTOR.
US5197516A (en) * 1992-05-01 1993-03-30 Moog Controls, Inc. Hydraulic servo valve with controlled disengagement feature

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1702056A (en) * 1926-05-14 1929-02-12 Thomas E Murray Pump for refrigerants
US1719825A (en) * 1926-05-13 1929-07-09 Thomas E Murray Pump for refrigerants and the like
DE670218C (en) * 1936-11-27 1939-01-14 Otto Wagner Bellows seal of pendulum rods
FR1031957A (en) * 1951-02-01 1953-06-29 Sealed transmission device
US2790427A (en) * 1955-09-23 1957-04-30 Ex Cell O Corp Flow control servo valve
US2797666A (en) * 1955-06-29 1957-07-02 John G Chubbuck Pulse proportioning dual integrating servomechanism
US2806480A (en) * 1954-09-01 1957-09-17 Foxboro Co Differential pressure responsive apparatus
US2835265A (en) * 1955-11-16 1958-05-20 Bendix Aviat Corp Transfer valve

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1719825A (en) * 1926-05-13 1929-07-09 Thomas E Murray Pump for refrigerants and the like
US1702056A (en) * 1926-05-14 1929-02-12 Thomas E Murray Pump for refrigerants
DE670218C (en) * 1936-11-27 1939-01-14 Otto Wagner Bellows seal of pendulum rods
FR1031957A (en) * 1951-02-01 1953-06-29 Sealed transmission device
US2806480A (en) * 1954-09-01 1957-09-17 Foxboro Co Differential pressure responsive apparatus
US2797666A (en) * 1955-06-29 1957-07-02 John G Chubbuck Pulse proportioning dual integrating servomechanism
US2790427A (en) * 1955-09-23 1957-04-30 Ex Cell O Corp Flow control servo valve
US2835265A (en) * 1955-11-16 1958-05-20 Bendix Aviat Corp Transfer valve

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3137309A (en) * 1962-04-30 1964-06-16 Link Division General Prec Inc Frictionless zero spring rate seal
US3233623A (en) * 1962-12-04 1966-02-08 Bell Aerospace Corp Multi-input control mechanism for hydraulic servo valve
FR2586870A1 (en) * 1985-09-04 1987-03-06 Applic Mach Motrices TORQUE MOTOR WITH HYDRAULIC POTENTIOMETER FOR SERVO-DISTRIBUTOR.
EP0214911A1 (en) * 1985-09-04 1987-03-18 S.A.M.M.- Société d'Applications des Machines Motrices Torque motor with a hydraulic potentiometer for a servo distributor
US5197516A (en) * 1992-05-01 1993-03-30 Moog Controls, Inc. Hydraulic servo valve with controlled disengagement feature

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