US3805843A - Electro-hydraulic transducer - Google Patents

Electro-hydraulic transducer Download PDF

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Publication number
US3805843A
US3805843A US13952371A US3805843A US 3805843 A US3805843 A US 3805843A US 13952371 A US13952371 A US 13952371A US 3805843 A US3805843 A US 3805843A
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US
United States
Prior art keywords
conduit
wall
arrangement
bore
liquid
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
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English (en)
Inventor
I Cyphelly
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Moog GAT GmbH
Original Assignee
Cyphelly Ivan J
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from CH682270A external-priority patent/CH523433A/de
Application filed by Cyphelly Ivan J filed Critical Cyphelly Ivan J
Application granted granted Critical
Publication of US3805843A publication Critical patent/US3805843A/en
Assigned to GLYCO-ANTRIEBSTECHNIK GMBH reassignment GLYCO-ANTRIEBSTECHNIK GMBH ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: CYPHELLY, IVAN J.
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/08—Servomotor systems incorporating electrically operated control means
    • 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
    • F15B13/0433—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 pressure control valves
    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/042—Controlling the temperature of the fluid
    • 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
    • F15B5/00—Transducers converting variations of physical quantities, e.g. expressed by variations in positions of members, into fluid-pressure variations or vice versa; Varying fluid pressure as a function of variations of a plurality of fluid pressures or variations of other quantities
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15C—FLUID-CIRCUIT ELEMENTS PREDOMINANTLY USED FOR COMPUTING OR CONTROL PURPOSES
    • F15C1/00—Circuit elements having no moving parts
    • F15C1/02—Details, e.g. special constructional devices for circuits with fluid elements, such as resistances, capacitive circuit elements; devices preventing reaction coupling in composite elements ; Switch boards; Programme devices
    • F15C1/04—Means for controlling fluid streams to fluid devices, e.g. by electric signals or other signals, no mixing taking place between the signal and the flow to be controlled
    • 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
    • Y10T137/0318—Processes
    • Y10T137/0391—Affecting flow by the addition of material or energy
    • 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
    • Y10T137/206—Flow affected by fluid contact, energy field or coanda effect [e.g., pure fluid device or system]
    • Y10T137/218—Means to regulate or vary operation of device
    • Y10T137/2191—By non-fluid energy field affecting input [e.g., transducer]
    • Y10T137/2196—Acoustical or thermal energy

Definitions

  • the invention provides a restricted throttling zone with electrically operated heating means which respond to the electric signal to be converted for varying the temperature, and thereby the viscosity or fluidity of a liquid supplied to the throttling zone under pressure.
  • the liquid is guided through the zone in a predominantly laminar flow pattern.
  • the change in viscosity produces a corresponding change in the flow rate of the liquid through the throttling zone, and the change in the flow rate provides the desired hydraulic signal.
  • the invention resides in a method of converting an electric signal to a hydraulic signal inwhich a liquid is supplied under pressure to a restricted throttling zone.
  • Theenergy of the electric signal is converted in the zone to thermal energy, and the latter is transmitted to the liquid in the zone, whereby the temperature and viscosity of the liquid are changed, and its flow rate through the throttling zone is increased, the increase in flow rate constituting the desired hydraulic signal.
  • FIG. 1 shows a first transducer arrangement of the invention in elevational section
  • FIG. 2 illustrates the device of FIG. I'in section on the line II II; p g
  • FIG. 3 shows another transducer arrangement of the invention in elevational section
  • FIGS. 4,5, and 6 respectively illustrate the device of FIG. 3 in section on the lines lV-IY, V-V, and VI- -VI;
  • FIGS. 7 and 8 illustrate a modified transducer in views corresponding to those of FIGS. 1 and 2 respec-, tively;
  • FIGS. 9 and 10 illustrate two additional transducer FIG. l4is a view of the device of FIG. 13 in fragmentary section on the line XIV-XIV;
  • FIG. 15 is a sectional elevation of a valve operated by a transducer of the invention.
  • FIG. 16 shows a portion of the apparatus of FIG. 15 in an exploded perspective view on a larger scale
  • FIG. 17 shows yet another transducer arrangement of the invention in fragmentary elevational section on the lineXVII-XVII in FIG. 18;
  • FIG. 18 illustrates the apparatus of FIG. 17 in section on the line XVIII-XVIII;
  • FIG. 19 is a diagram of a modification of the device of FIG. 17.
  • FIG. 20 shows a modification of the devices of FIGS. 17 to 19 on a larger scale.
  • FIGS. 1 and 2 there is seen a particularly simple transducer arrangement of the invention.
  • a cylindrical metal tube 1 of limited electrical conductivity is secured at one end by a solder joint 2 in a relatively heavy mounting flange 3.
  • the other end of the tube 1 is soldered to a lug 4 attached to a cable 5.
  • the tube 1 may consist of nickel-chromium or nickel-chromium-iron alloy of the type commonly employed in electric heating elements, but preferably consists of a titanium alloy containing at least 80% titanium or a zirconium alloy containing at least 50 percent zirconium, the titanium and zirconium alloys combining high electrical resistance with low heat capacity.
  • the steel flange 3 is normally fastened to a grounded metal object, and the liquid whose flow velocity is to be controlled is supplied to an orifice of the'tube 1- at a I longitudinally through the wall .of the tube 1 from the cable 5 to ground, the lug 4 being supported in the air by the tube 1, and thereby electrically insulated.
  • the current passing through the tube 1 heats the latter and the liquid in' the tube.
  • the resulting temperature increase of the liquid typically hydraulic fluid or oil, decreases the viscosity of the liquid, and the flow ratethrough the throttling zone provided by the tube 1 is increased.
  • the hydraulic signal constituted by the increase in flow rate may be used for controlling suitable devices as will presently become apparent.
  • FIGS. 3 to 6 show a modification of the transducer arrangement of FIGS. 1 and 2 in which the cross section of atube 1', otherwise closely similar to the tube 1, gradually varies from a circle at the tube end soldered to a flange 3' to a flattened loop at the end soldered to a lug 4'.
  • the device of FIGS. 3 and 4 produces a greater change in the flow velocityor flow rate of a liquidthan that described above.
  • the change arrangements of the invention in views corresponding to thatof FIG. 2;
  • FIG. 1 1 shows yet another transducer arrangement in elevational section
  • FIG. 12 shows the device of FIG. 11 in fragmentary section on the line XII-XII; i
  • FIG. 13 illustrates a further transducer arrangemen of the invention in elevational section
  • the transducer arrangement illustrated in FIGS. 7 and 8 differs from that illustrated in FIGS. 1 and 2 by a tube 1". of uniform cross section similar to that shown in FIG. 6. Liquid flows through the tubefl'fas a relatively thin ribbon
  • the flattened tube offers relatively little resistance .to internal liquid pressure and is therefore reinforced by circular discs 6 perpendicular to the tube axis and soldered to the tube 1'' in axially' spaced relationship.
  • the discs 6 also constitute cooling ribs on the tube 1" which hasten return of the liquid temperature in the tube to ambient temperature as soon as the electric heating signal is interrupted.
  • FIG. 9 shows only the tube 1 of the first-described embodiment spacedly enclosed in a jacket 7 through which a cooling fluid may be passed as indicated by curved arrows.
  • the starting temperature of the liquid in the throttling tube may thus be selected at will and is independent of the ambient temperature.
  • FIG. 10 shows an arrangement, identical with that of FIGS. 1 and 2, as far as not explicitly shown otherwise, in which the liquid flow rate responds with only a minimal delay to the application of an electric heating signal.
  • the tube 1 is mounted coaxiallyin a glass tube 8, and the annular space between the tubes 1, 8 is evacuated! Thermal losses from the tube 1 are essentially limited in this arrangement to insignificant radiation losses,
  • the tube which guides the liquid through the throttling zone consists of electrically conductive material and alsofunctions as a heating elementr
  • This arrangement is structurally relatively simple, and heat transfer through the relatively large tube wall is effective.
  • the response of the transducer- is inherently somewhat slow because the heating element also performs'structural functions and must be made heavy enough to withstand the internal hydraulic pressure, normally much higher than atmospheric 'pressure. Even with the use of materials'of constructions having low heat capacity, a lag in response is unavoidable. It is also difficult to produce sufficiently uniform tubing in the capillary dimensions (1 mm flow section or less) in which the throttling tubes of the invention are most useful.
  • the response of the transducer arrangement to the electric input signal can be'hastenedby assigning the guiding and heating functions to separate structuralelements, that is, by installing a heating element coaxially in the conduit which guides the liquid flow in a predominantly-laminar pattern.
  • Theithermal capacity of the heating element canbe reducedto'an insignificant value in such an arrangement.
  • Nickel-chromium, nickelchromium iro'n, titanium alloys, zirconium alloys, and the like, may be employed for the heating elements as discussed above. '1.
  • the throttling passage is partlyconstitutedby a bore 11in aheavy glass .plate:.l 2 which thermally insulates. the liquid flowin'g through thegbore 11.
  • Metal washers 14a, l4baxially aligned wiht the bore 11 are fastened to the opposite surfacesrof theplate 12 and carry respective metal'bra'ckets 13a, 13b which have free ends axially'offset from the orifices of the throttling passage in the washers 1"4a,.14b.
  • FIGS. 15 and 16 illustrate the application of the aforedescribed transducer arrangements to the control of a hydraulic valve.
  • an externally heated throttling conduit is being shown by way of Example as in FIGS. 1 to 10. It will be understood, however, that an internally heated throttling passage may be provided in the device shown in FIGS. 15 and 16 without significantly affecting the. operation of the apparatus.
  • FIG. 15 there is seen a valve casing 26 which receivesa slidelvalve 15 in a stepped cylindrical bore-The valve'contr'olsflow of hydraulic fluid betwen a supply'conduit 25,.
  • two operating conduits22, 23 and a return conduit-24.,A pump not shown, withdraws returned fluid from a .sump 'connected to the conduit 24 and delivers it tothe conduit 25 at an'elevated pressure P;
  • both operating conduits 22, 23 are blocked.
  • the operating conduit 22 is connected to the supply conduit 25, and the operating conduit 23 is vented to the non-illustratedsump-through the return conduit24.
  • the flow in'the operating conduits 22, 23 is reversed when the valve moves toward the right from-theillustrated position.
  • the narrow end of the stepped cylindrical bore in the valve casing 26 is permanently connected with theconduit 25, and the full pressureof the hydraulic fluid acts on the smaller end face 16 of the valve 15.
  • the fluid pressure on a piston 17 of the valve 15 in the larger end of the stepped bore must assume a smaller value P P v mounted on the casing 26 and projectinglinto thelorifice ofan axial bore of the valve ⁇ 15.
  • the tepped bore in the c'asin'giZG isconnected with the return conduit 24' by a'throttling tube 18 of theinven; tionandaninsulating'tubefl8f
  • the flow rate through the tube l8 may'be changedsby increasin'g or 'decrea s'r ing the output currentof a signal amplifier 21 to the in-- sulated end and to the grounded-end of the tube 18,.
  • the trimmer 19 iss et in such a manner that no fluid flows through the needle valve 20 as.long 'as,the'-. tube I8.is heatedzto aninterrnediate'value.
  • the pressure Pcan be maintained only by increasedflow of fluid through the needle valve 20, nd the valve 15 moves; from the illustrated position toward the right to providean adequate flow section at the needle valve '20.
  • the oppositeeffect is" achievedibyl reducing the heating "current. i
  • the trimmer valve 19 is shown in more detail in FIG. 16. Its base plate 30 is normally bolted to the valve casing 26. A capillary tube 27 is sealed by soldering in two passages 28, 29 of the base plate 30 which communicate with the supply conduit 25 and the large end of the stepped valve bore in the installed throttle 19. The tube 27 is coiled in more than one turn about a threaded stud upwardly extending from the base plate 30. A washer 33 may be lowered on the tube 27 by means of a nut 32 engaging the stud 31 elastically to deform the tube 27 and thereby to reduce the effective flow section of the same.
  • the transducer arrangements of the invention are provided with throttling tubes whose electrical resistance converts the electrical energy of an applied signal to thermal energy, it has been found advisable to protect the sensitive tubes against an electrical, and thus also a thermal overload.
  • FIGS. 17 and 18 A suitable protection arrangement is shown in FIGS. 17 and 18.
  • the tube 41 expands mainly longitudinally when heated. It is fixedly attached by one longitudinal end to a grounded, conductive support 42 formed with a supply bore 42a and a discharge bore 42b of substantially greater flow section than the throttling tube 41 with which the communicate.
  • the other longitudinal end is soldered to a lug 43 held in a fixed position on the support 42 by an interposed wafer 44 of insulating material.
  • Heating current is supplied to the tube 41 by a cable 45 on the lug 43 and the ground connection of the support 42. Liquid flows through the tube between the bores of the support 42 and of the lug 43.
  • the center of the tube 41 is laterally offset from a straight line through the two ends by a small amount.
  • the tube 41 buckles as shown in broken lines at 41 to cut the beam 46 of a light source 47 which is directed toward a photo-electric cell 47.
  • the cell is arranged in circuit with a relay, not shown, which interrupts the electric heating'signal fed to the tube 41 in a conventional manner evident from FIG. 19.
  • FIG. 19 diagrammatically illustrates a mechanical equivalent of the photoelectric safety switch arrangement described with reference to FIGS. 17 and 18. buckled, buckles, the tube 41 engages the actuating element 52 of a switch 53 and thereby interrupts the output circuit of an amplifier 51 which supplies heating current.
  • the arrangement of FIG. 19 is somewhat less reliable'than that of FIGS. 17 and 18 because of the use of moving mechanical elements, and the aforedescribed safety arrangement is preferred.
  • the distance between the two fastened ends of the tube 41 must be maintained constant for a reproducible buckling effect. It is necessary, therefore, to prevent or at least to minimize heating ofthe supporting structure. This can be achieved in a simple manner as shown in FIG. 20.
  • a terminal portiona of the tube 41 iscoated with a thin layer 54 of highly conductive metal, such as copper or silver, which provides a shunt across the terminal tube portion and prevents heating of the same and of the associated supporting structure by the passing electric current.
  • the tube 41 is thin enough and made of material of sufiiciently poor thermal conductivity to prevent the flow of significant amounts of thermal energy through the terminal portion a.
  • Heating of the support 42 by. the hydraulic fluid can be held to an insignificant value by making the support- 42 of alumiby attaching it to a heat sink, such as the valve casing 26 (FIG. 17).
  • An electro-hydraulic transducer arrangement for converting an electric signal to a hydraulic signal, the arrangement comprising:
  • an elongated conduit having a longitudinal wall of electrically conductive material, said wall defining a longitudinal throttling bore in said conduit;
  • discharge means for discharging said liquid :fro
  • said wall being shaped to guide said liquid through said bore in a predominantly laminar 2. the heating of said wall by said electric signal being sufficient to increase the'temperature of the flowing liquid and thereby decrease the viscosity thereof;
  • said switch means including a light source and a photoelectric cell arranged in the beam of said light source, said conduit. interrupting said beam when buckled.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Theoretical Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Control Of Resistance Heating (AREA)
  • Servomotors (AREA)
  • Instantaneous Water Boilers, Portable Hot-Water Supply Apparatuses, And Control Of Portable Hot-Water Supply Apparatuses (AREA)
US13952371 1970-05-06 1971-05-03 Electro-hydraulic transducer Expired - Lifetime US3805843A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH682270A CH523433A (de) 1970-05-06 1970-05-06 Elektro-hydraulischer Wandler
CH459371A CH535898A (de) 1970-05-06 1971-03-30 Elektro-hydraulischer Wandler

Publications (1)

Publication Number Publication Date
US3805843A true US3805843A (en) 1974-04-23

Family

ID=25695835

Family Applications (1)

Application Number Title Priority Date Filing Date
US13952371 Expired - Lifetime US3805843A (en) 1970-05-06 1971-05-03 Electro-hydraulic transducer

Country Status (9)

Country Link
US (1) US3805843A (xx)
JP (1) JPS5426731B1 (xx)
BE (1) BE766726A (xx)
CH (1) CH535898A (xx)
FR (1) FR2088372B1 (xx)
GB (1) GB1347317A (xx)
NL (1) NL7106109A (xx)
NO (1) NO138260C (xx)
SE (1) SE371258B (xx)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105546164A (zh) * 2016-01-07 2016-05-04 上海宝冶工程技术有限公司 一种高温耐腐蚀介质制备纯化设备的冷冻阀门

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1911066A (en) * 1930-05-05 1933-05-23 Doble Abner Thermostat construction
US3334641A (en) * 1964-06-26 1967-08-08 Johnson Service Co Fluid stream control apparatus
US3678243A (en) * 1969-12-27 1972-07-18 Chisso Corp Method for levelling the temperature of an electrically heated pipeline

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1911066A (en) * 1930-05-05 1933-05-23 Doble Abner Thermostat construction
US3334641A (en) * 1964-06-26 1967-08-08 Johnson Service Co Fluid stream control apparatus
US3678243A (en) * 1969-12-27 1972-07-18 Chisso Corp Method for levelling the temperature of an electrically heated pipeline

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105546164A (zh) * 2016-01-07 2016-05-04 上海宝冶工程技术有限公司 一种高温耐腐蚀介质制备纯化设备的冷冻阀门
CN105546164B (zh) * 2016-01-07 2017-11-14 上海宝冶工程技术有限公司 一种高温耐腐蚀介质制备纯化设备的冷冻阀门

Also Published As

Publication number Publication date
FR2088372A1 (xx) 1972-01-07
FR2088372B1 (xx) 1974-04-26
SE371258B (xx) 1974-11-11
CH535898A (de) 1973-04-15
NO138260B (no) 1978-04-24
DE2119957B2 (de) 1976-12-09
NL7106109A (xx) 1971-11-09
JPS5426731B1 (xx) 1979-09-05
DE2119957A1 (de) 1971-11-25
GB1347317A (en) 1974-02-27
BE766726A (fr) 1971-10-01
NO138260C (no) 1978-08-02

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AS Assignment

Owner name: GLYCO-ANTRIEBSTECHNIK GMBH, STIELSTRASSE 18, D-62

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:CYPHELLY, IVAN J.;REEL/FRAME:004224/0085

Effective date: 19840124