WO2010016314A1 - サーボ弁 - Google Patents
サーボ弁 Download PDFInfo
- Publication number
- WO2010016314A1 WO2010016314A1 PCT/JP2009/059859 JP2009059859W WO2010016314A1 WO 2010016314 A1 WO2010016314 A1 WO 2010016314A1 JP 2009059859 W JP2009059859 W JP 2009059859W WO 2010016314 A1 WO2010016314 A1 WO 2010016314A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- pressure
- flapper
- chamber
- fluid
- nozzle
- Prior art date
Links
- 239000012530 fluid Substances 0.000 claims abstract description 80
- 238000003825 pressing Methods 0.000 claims description 80
- 239000003921 oil Substances 0.000 description 53
- 239000000853 adhesive Substances 0.000 description 11
- 230000001070 adhesive effect Effects 0.000 description 11
- 239000002184 metal Substances 0.000 description 8
- 238000010586 diagram Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 7
- 230000002093 peripheral effect Effects 0.000 description 7
- 238000006073 displacement reaction Methods 0.000 description 3
- 238000009434 installation Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000011144 upstream manufacturing Methods 0.000 description 3
- 230000001276 controlling effect Effects 0.000 description 2
- 239000010720 hydraulic oil Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229910000679 solder Inorganic materials 0.000 description 1
Images
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
- 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
-
- 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
- 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
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/08—Characterised by the construction of the motor unit
- F15B15/14—Characterised by the construction of the motor unit of the straight-cylinder type
-
- 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
- Y10T137/8593—Systems
- Y10T137/86493—Multi-way valve unit
- Y10T137/86574—Supply and exhaust
- Y10T137/86582—Pilot-actuated
- Y10T137/86614—Electric
-
- 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
- Y10T137/8593—Systems
- Y10T137/86493—Multi-way valve unit
- Y10T137/86574—Supply and exhaust
- Y10T137/8667—Reciprocating valve
- Y10T137/86694—Piston valve
- Y10T137/8671—With annular passage [e.g., spool]
Definitions
- the present invention relates to a servo valve.
- Servo valves are widely used to control the driving of hydraulic or pneumatic actuators.
- Some servo valves use a spool that is reciprocated as a valve element.
- a nozzle flapper mechanism as shown in Patent Document 1 has been proposed. This is because a variable orifice is formed by a pair of nozzles and a flapper installed between the two nozzles, the back pressure of both nozzles varying according to the position of the flapper is derived, and the pressure difference between the derived back pressures Thus, the spool is operated.
- the position displacement of the flapper is performed by an electromagnetic coil.
- the servo valve is required to be smaller and higher in performance.
- a device using a multilayer piezoelectric element or a bimorph piezoelectric element has been proposed.
- an object of the present invention is to provide a servo valve that can be manufactured at low cost by simplifying the relative position adjustment between a nozzle and a flapper and simplifying the configuration of a valve body drive circuit.
- a valve body attached so as to be capable of reciprocating, a first pressing portion and a second pressing portion that press the valve body in opposite directions by fluid pressure, and the first pressing portion
- a servo valve provided with a valve body drive circuit for supplying fluid to the second pressing portion and reciprocating the valve body by adjusting the pressure of the supplied fluid, wherein the valve body drive circuit is And a servo provided with a nozzle flapper mechanism for maintaining the fluid pressure of the first pressing portion at a substantially constant magnitude and adjusting the fluid pressure of the second pressing portion at a fluid outlet portion from the second pressing portion. It is a valve.
- the valve body attached so as to be able to reciprocate is pressed in the opposite direction by the fluid pressure of the first pressing portion and the second pressing portion, the pressure difference between the fluid pressure of the first pressing portion and the second pressing portion It will reciprocate. That is, the valve element moves in a direction in which the fluid pressure of the pressing portion having the larger fluid pressure acts among the fluid pressures of the first pressing portion and the second pressing portion.
- the fluid pressure of the first pressing portion is maintained at a substantially constant magnitude, the fluid pressure of the second pressing portion is adjusted to be larger or smaller than the fluid pressure of the first pressing portion. The body reciprocates.
- the fluid pressure of the second pressing portion is adjusted by adjusting the distance between the tip of the nozzle provided at the fluid outlet portion and the flapper. Can be adjusted. If the fluid pressure of the second pressing part can be adjusted, the fluid pressure of the second pressing part can be adjusted. Therefore, the fluid pressure of the second pressing part is larger than the fluid pressure of the first pressing part having a constant size. Can be made smaller.
- the nozzle flapper mechanism is installed only at the outlet of the second pressing portion, that is, the flapper is only installed facing one nozzle, the position of the flapper with respect to the nozzle is easily adjusted. be able to. Thereby, the flapper can be installed accurately and in a short time.
- the circuit configuration of the valve body driving circuit is simplified, the processing cost of the valve body can be reduced. Accordingly, the servo valve can be manufactured at a low cost.
- a fluid passage to the first pressing portion is provided with a throttle having an appropriate area so that the fluid pressure is maintained substantially constant. do it.
- the first pressure receiving area where the fluid of the first pressing portion in the valve body acts on the valve body and the second pressure receiving area where the fluid of the second pressing portion acts on the valve body are approximately. It may be the same area.
- the fluid force of the first pressing portion is obtained by multiplying the first pressure receiving area by the fluid pressure of the first pressing portion.
- the fluid force of the second pressing part is obtained by multiplying the second pressure receiving area by the fluid pressure of the second pressing part. Since the first pressure receiving area and the second pressure receiving area are substantially the same area, the relative magnitudes of the fluid pressures of the first pressing part and the second pressing part are determined by the pressures of the respective fluids.
- the pressure of the liquid in the first pressing part is selected so as to be equal to the intermediate pressure in the intermediate part in the fluid pressure range of the second pressing part adjusted by the nozzle flapper mechanism.
- the pressure of the fluid of the second pressing part in other words, the fluid pressure of the second pressing part is made larger or smaller than the pressure of the fluid of the first pressing part that is kept constant, in other words, the fluid pressure of the first pressing part. Therefore, the valve body can be reciprocated.
- the pressure of the fluid in the first pressing portion is the pressure of the fluid in the second pressing portion when no voltage is applied to the nozzle flapper mechanism and the second pressure in the state where the maximum voltage is applied to the nozzle flapper mechanism.
- it is selected to be approximately equal to the middle fluid pressure.
- the 1st pressure receiving area where the fluid of the said 1st press part in the said valve body acts on the said valve body differs from the 2nd pressure receiving area where the fluid of the said 2nd pressing part acts on the said valve body. It may be an area.
- the fluid force of the first pressing portion is obtained by multiplying the first pressure receiving area by the fluid pressure of the first pressing portion.
- the fluid force of the second pressing part is obtained by multiplying the second pressure receiving area by the fluid pressure of the second pressing part.
- the pressure of the fluid of the first pressing portion is such that the intermediate pressure in the intermediate portion in the fluid pressure range of the second pressing portion adjusted by the nozzle flapper mechanism is multiplied by the second pressure receiving area / first pressure receiving area. Selected.
- the pressure of the fluid of the first pressing portion is selected to be a magnitude obtained by multiplying the intermediate pressure of the fluid of the second pressing portion by the second pressure receiving area / first pressure receiving area.
- the first pressing portion is supplied from the supply source. Even if the supplied fluid is introduced as it is, the same pressure as the intermediate pressure can be obtained. In other words, by setting the intermediate pressure of the fluid supplied to the second pressing portion to a magnitude obtained by multiplying the pressure of the supplied fluid by the first pressure receiving area / the second pressure receiving area, the fluid pressure of the first pressing portion is reduced.
- the member which adjusts the pressure of the fluid supplied to the 1st press part can be made unnecessary.
- the circuit configuration of the valve body drive circuit is further simplified, so that the processing cost of the valve body can be further reduced, and the servo valve can be manufactured at a lower cost.
- the flapper of the nozzle flapper mechanism may be operated by a bimorph piezoelectric element.
- a bimorph piezoelectric element that has a relatively large displacement and can be driven at a low voltage is used, a small nozzle flapper mechanism including the power supply portion can be configured.
- the bimorph piezoelectric element is relatively inexpensive, and the servo valve can be manufactured at a lower cost.
- the flapper of the nozzle flapper mechanism may be operated by a stacked piezoelectric element. Since the flapper adjusts the distance with respect to one nozzle, only one laminated piezoelectric element that moves the flapper may be used. For this reason, since it can comprise small compared with what has a large laminated type piezoelectric element on both sides of a flapper, a servovalve can be reduced in size comparatively. In addition, control of the control system for moving the flapper is relatively easy. Thus, a servo valve that can be used practically can be provided.
- the flapper of the nozzle flapper mechanism may be operated by a torque motor.
- a torque motor By using a proven torque motor, a servo valve capable of stable adjustment can be configured.
- the servo valve according to the present invention includes a nozzle flapper mechanism that maintains the pressure of the first pressing portion at a substantially constant magnitude and adjusts the pressure of the second pressing portion at the fluid outlet portion from the second pressing portion. Therefore, the position of the flapper with respect to the nozzle in the nozzle flapper mechanism can be easily adjusted. Thereby, the flapper can be installed accurately and in a short time. In addition, since the circuit configuration of the valve body driving circuit is simplified, the processing cost of the valve body can be reduced. Accordingly, the servo valve can be manufactured at a low cost.
- FIG. 10 is a sectional view taken along line XX in FIG. 9.
- FIG. 10 is a YY sectional view of FIG. 9.
- FIG. 1 is a circuit diagram showing a spool drive circuit (valve drive circuit) 3 of the servo valve 1.
- FIG. 2 is a partial cross-sectional view showing a part of the nozzle flapper mechanism.
- a spool (valve element) 5 that controls driving of a hydraulic actuator (not shown) is movable in the axial direction.
- the spool 5 has a function of switching the supply direction of hydraulic oil to the hydraulic actuator according to the position in the axial direction.
- the axial position of the spool 5 is detected by a position detector (not shown).
- Both ends of the spool 5 are provided with a first chamber (first pressing portion) 7 and a second chamber (second pressing portion) 9 which are spaces in which the spool 5 side is open.
- the spool drive circuit 3 is provided with a pump 11 for supplying oil (fluid). Oil from the pump 11 is branched into a first passage 13 and a second passage 15. Oil passing through the first passage 13 is supplied to the first chamber 7 and returned to the tank 17. The oil passing through the second passage 15 is supplied to the second chamber 9 and then discharged to the pipe 19. The oil discharged to the pipe 19 is returned to the tank 17.
- the pressure receiving area of the spool 5 on which the oil in the first chamber 7 and the second chamber 9 acts is substantially the same area.
- the fluid pressure differential pressure at which the oil in the first chamber 7 and the second chamber 9 acts on the spool 5 is proportional to the oil pressure differential pressure.
- the first passage 13 is provided with a first throttle 21 on the upstream side of the first chamber 7 and a pressure adjusting throttle 23 on the downstream side of the first chamber 7.
- the first throttle 21 is, for example, an orifice, and regulates the pressure of oil supplied to the first chamber 7.
- the pressure P 1 of the oil supplied to the first chamber 7, for example, has a substantially half of the pressure Ps of the oil ejected from the pump 11.
- the pressure adjusting throttle 23 has a variable opening area and adjusts the pressure of the oil in the first chamber 7.
- the second passage 15 is provided with a second throttle 25 on the upstream side of the second chamber 9 and a nozzle flapper mechanism 27 on the downstream end.
- the second diaphragm 25 is, for example, an orifice, and the opening area thereof is the same as that of the first diaphragm 21.
- the nozzle flapper mechanism 27 includes a nozzle 29 attached to the downstream end of the second passage 15, and a flapper portion 31 that is installed to face the opening 33 of the nozzle 29 and forms a diaphragm.
- the nozzle 29 is a throttle mechanism, the opening area of the opening 33 is equal to the opening area of the pressure adjusting throttle 23 at the origin position (a state where no voltage is applied to the flapper 35).
- the pressure is equal to the oil pressure in the first chamber 7.
- the pressure of the oil in the second chamber 9 at the origin position is an intermediate pressure located at an intermediate portion of the range adjusted by the nozzle flapper mechanism 27.
- FIG. 3 is a cross-sectional view illustrating a schematic configuration of the flapper unit 31.
- the flapper 31 is provided with a flapper 35 and a case 37 that holds the flapper 35.
- the case 37 is made of metal and has a hollow rectangular parallelepiped shape with one surface open.
- the flapper 35 is configured by bonding two plate-like piezoelectric elements 41 and 43 to both surfaces of a metal plate 39, that is, a bimorph piezoelectric element.
- An electric wire 45 is attached to one end of the metal plate 39 and the piezoelectric elements 41 and 43.
- the metal plate 39 is grounded, and a positive voltage is applied to the piezoelectric element 41 and a negative voltage is applied to the piezoelectric element 43.
- One end of the flapper 35 is inserted into the internal space of the case 37, and is fixed to the case 37 by an adhesive 47 together with the electric wires 45.
- the adhesive material 47 is a resin having electrical insulation, and for example, a molding agent such as an epoxy resin is used.
- the side area of the cylinder formed by the flapper 35 and the tip outer peripheral end 49 of the nozzle 29 is the amount of restriction of the nozzle flapper mechanism 27.
- the position where the side area becomes equal to the opening area of the opening 33 is a limit position where the nozzle flapper mechanism 27 has a diaphragm function. That is, when the flapper 35 is further away from the nozzle 29 than this position, the throttle effect becomes smaller than the throttle effect of the nozzle 29, so the nozzle flapper mechanism 27 does not perform the throttle function.
- the flapper 35 is installed so as to be positioned between the limit position and the position where the flapper 35 and the nozzle 29 are in contact, and the position between the limit position and the position where the flapper 35 and the nozzle 29 are in contact with each other is the center. To be displaced.
- plate-like piezoelectric elements 41 and 43 are attached to both surfaces of the metal plate 39.
- the electric wire 45 is joined to one end of the metal plate 39 and the piezoelectric elements 41 and 43 by, for example, solder.
- the metal plate 39 and the peripheral portion of the contact point between the piezoelectric elements 41 and 43 and the electric wire 45 are fixed by the adhesive 47 to form the flapper 35.
- the amount of the adhesive 47 is small, it does not cause a situation such as deformation of the electric wire 45. That is, the contact is not separated and the electric wire 45 is not deformed into contact with the case.
- the insulation resistance of the electric circuit is measured to confirm that it is reliably insulated.
- the flapper 35 is incorporated into a predetermined position of the case 37, and an adhesive 47 is injected into the internal space of the case 37.
- a large force acts on the flapper 35 by the injection of the adhesive material 47, the contact between the metal plate 39 and the piezoelectric elements 41 and 43 and the electric wire 45 is protected by the previously cured adhesive material 47. Will never leave.
- the movable part of the electric wire 45 is not long, it does not deform
- the first jig 53 has a through hole 57 having a rectangular cross section. One end of the through hole 57 is provided with an enlarged portion that can be installed so that the front end surface 51 of the case 37 is orthogonal to the through hole.
- the second jig 55 is formed so that one end side is inserted into the through hole 57.
- the second jig 55 is provided with a through hole 59 into which the flapper 35 is inserted.
- the through hole 57 and the through hole 59 have the same vertical center position.
- the case 37 is inserted into the through hole 57 from the flapper 35 side, and is fitted into the enlarged portion.
- the second jig 55 is inserted from the opposite side of the through hole 57 and the tip of the flapper 35 is inserted into the through hole 59. In this way, the front end surface 51 of the case 37 and the surface of the flapper 35 are orthogonal to each other.
- the adhesive 47 is cured, and the flapper 35 is fixed to the case 37 such that the tip surface 51 of the case 37 and the surface of the flapper 35 are orthogonal to each other.
- the adhesive 47 may be injected while the flapper 31 is held by the first jig 53 and the second jig 55.
- the operation of the spool drive circuit 3 configured as described above will be described.
- the pump 11 When the pump 11 is operated and oil is supplied, the supplied oil is branched and flows into the first passage 13 and the second passage 15.
- the oil flowing into the first passage 13 is depressurized by the first throttle 21, flows into the first chamber 7, and returns to the tank 17 through the pressure adjustment throttle 23.
- the oil that has flowed into the second passage 15 is depressurized by the second throttle 25 and flows into the second chamber 9.
- the oil is discharged from the second chamber 9 through the nozzle flapper mechanism 27 to the pipe 19 and returned from the pipe 19 to the tank 17.
- the opening area of the opening 33 is equal to the opening area of the pressure adjusting throttle 23, so the pressure in the second chamber 9 is the same as the pressure in the first chamber 7, The differential pressure between the first chamber 7 and the second chamber 9 is zero.
- the spool 5 is stopped.
- the flapper 35 When a voltage of ⁇ (+) is applied to the flapper 35, the flapper 35 is displaced in a direction away from the nozzle 29, and the side area of the cylinder formed by the flapper 35 and the tip outer peripheral end 49 of the nozzle 29, that is, the nozzle flapper mechanism 27.
- the amount of throttle is larger than that of the pressure adjusting throttle 23.
- the throttle amount of the nozzle flapper mechanism 27 is larger than that of the pressure adjustment throttle 23, the pressure in the second chamber 9 becomes smaller than that in the first chamber 7, and a differential pressure is generated between the first chamber 7 and the second chamber 9. Due to this differential pressure, the spool 5 moves to the second chamber 9 side.
- the pressure in the second chamber 9 is made larger than the pressure in the first chamber 7 using the nozzle flapper mechanism 27 or The spool 5 reciprocates by adjusting it to a small value.
- this nozzle flapper mechanism 27 is installed only at the end of the second passage 15, that is, at the outlet of the second chamber 9, the flapper 35 is only installed facing one nozzle 29. Therefore, since the position of the flapper 35 can be easily adjusted with respect to the nozzle 29, the installation of the flapper unit 31 can be performed accurately and in a short time. Further, since the circuit configuration of the spool driving circuit 3 is simplified, the processing cost of the valve body can be reduced. Accordingly, the servo valve 1 can be manufactured at low cost.
- the bimorph type piezoelectric element that has a relatively large displacement and can be driven at a low voltage is used as the flapper 35, the small nozzle flapper mechanism 27 including the power supply portion can be configured.
- the bimorph piezoelectric element is relatively inexpensive, and the servo valve 1 can be manufactured at a lower cost.
- the flapper 35 of the nozzle flapper mechanism 27 may be operated by a laminated piezoelectric element 61 as shown in FIG. Since the flapper 35 adjusts the distance with respect to one nozzle 29, the number of the laminated piezoelectric elements 61 that move it is sufficient. For this reason, the servo valve 1 can be made relatively small because it can be made smaller than the one provided with the large laminated piezoelectric elements 61 on both sides of the flapper 35. Further, the control of the control system for moving the flapper 35 is relatively easy. Accordingly, it is possible to provide the servo valve 1 that can be put into practical use even when the laminated piezoelectric element 61 is used.
- the flapper 35 of the nozzle flapper mechanism 27 may be operated by a torque motor 63 that performs a linear operation as shown in FIG. If it does in this way, the servo valve 1 which can perform the stable adjustment can be comprised by using the torque motor 63 with a track record.
- FIG. 9 is a circuit diagram showing a spool drive circuit (valve drive circuit) 73 of the servo valve 71.
- FIG. 10 is a partial cross-sectional view showing a part of the nozzle flapper mechanism.
- 11 is a cross-sectional view taken along the line XX of FIG. 12 is a YY cross-sectional view of FIG.
- the servo valve 71 is provided with a body 75 having a space inside, and a spool (valve element) 77 disposed in the internal space of the body 75 so as to be movable in the axial direction.
- the spool 77 is provided with a plurality of land portions 79 having substantially the same diameter as a sliding surface. As the spool 77 moves in the axial direction, the positions of these land portions 79 in the axial direction move. These land portions 79 have a function of switching the supply direction of hydraulic oil to a hydraulic actuator (not shown) according to the position in the axial direction.
- a land portion 79 a provided at one end portion of the spool 77 is provided with a first rod 81 projecting outward. The first rod 81 transmits the operation to the differential transformer 83.
- the differential transformer 83 detects the position of the spool 77 in the axial direction.
- a first chamber (first pressing portion) 85 is formed outside the land portion 79a so as to surround the first rod 81.
- a land portion 79 b provided at the other end portion of the spool 77 is provided with a second rod body 87 projecting outward.
- a second chamber (second pressing portion) 89 is formed outside the land portion 79b so as to surround the second rod 87.
- the spool drive circuit 73 is provided with a pump 91 that supplies oil through the main passage 93.
- the main passage 93 is provided with a pressure regulating valve 95 to supply oil having a substantially constant pressure.
- the main passage 93 is branched into a first passage 97 and a second passage 99.
- the oil passing through the first passage 97 is supplied to the first chamber 85 and returned to the tank 105 through the pipe 101 and the return passage 103.
- the oil supplied through the main passage 93 is supplied to the first chamber 85 as it is.
- the pressure of the supplied oil is the pressure Ps ejected by the pump 91.
- the oil passing through the second passage 99 is supplied to the second chamber 89 and then returned to the tank 105 through the return passage 103 via the pipe 107.
- the first pressure receiving area A1 where the land portion 79a receives pressure from the oil supplied to the first chamber 85 is the land portion as shown in FIG.
- the size is obtained by subtracting the cross-sectional area of the first rod 81 from the area of 79a. Since the second rod body 87 penetrates the second chamber 89, the second pressure receiving area A2 where the land portion 79b receives pressure from the oil supplied to the second chamber 89 is the land portion as shown in FIG. It becomes the magnitude
- the sizes of the first rod 81 and the second rod 87 are set so that the first pressure receiving area A1 is approximately half the size of the second pressure receiving area A2.
- the area ratio between the first pressure receiving area A1 and the second pressure receiving area A2 is not limited to this.
- the second passage 99 is provided with an inlet throttle 109 made of, for example, an orifice on the upstream side of the second chamber 89.
- the pipe 107 is provided with a nozzle flapper mechanism 111.
- the nozzle flapper mechanism 111 is provided with a nozzle 113 attached to the pipe 107 and a flapper portion 117 which is installed opposite to the opening 115 of the nozzle 113 and forms a diaphragm.
- the flapper unit 117 includes a flapper 119 and a stacked piezoelectric element 121 in which a plurality of piezoelectric elements that operate the flapper 35 are stacked.
- the side area of the cylinder formed by the flapper 119 and the outer peripheral end 123 of the tip of the nozzle 113 is the aperture amount of the nozzle flapper mechanism 111.
- the position where the side area becomes equal to the opening area of the opening 115 is a limit position where the nozzle flapper mechanism 111 has a diaphragm function. That is, when the flapper 119 is further away from the nozzle 113 than this position, the throttle effect becomes smaller than the throttle effect of the nozzle 113, so that the nozzle flapper mechanism 111 does not perform the throttle function.
- the flapper 119 is installed so as to be located between the limit position and the position where the flapper 119 and the nozzle 113 are in contact, and the position where the limiter and the flapper 119 and the nozzle 113 are in contact with each other is the center (origin). , That is, between the adjustment range C.
- the specifications of the nozzle flapper 111 are set so that when the flapper 119 is at the origin position, the pressure P1 of the oil in the first chamber 85 is substantially the same as the pressure Ps supplied by the pump 91. Yes.
- the operation of the spool drive circuit 73 configured as described above will be described.
- oil is supplied from the tank 105 through the main passage 93.
- the pressure Ps of the supplied oil is maintained substantially constant by the pressure adjustment valve 95.
- the oil flowing through the main flow path 93 is branched and flows into the first passage 97 and the second passage 99.
- the oil that has flowed into the first passage 97 flows into the first chamber 85 as it is, and is returned to the tank 105 through the pipe 101 and the return passage 103.
- the oil that has flowed into the second passage 99 is depressurized by the inlet throttle 109 and flows into the second chamber 89.
- the oil is discharged from the second chamber 89 to the pipe 107 and returns to the tank 105 from the return passage 103 through the nozzle flapper mechanism 111.
- the side area of the cylinder formed by the flapper 119 and the tip outer peripheral end 123 of the nozzle 113, that is, the aperture amount of the nozzle flapper mechanism 111 is It becomes smaller than when it is at the origin position.
- the throttle amount of the nozzle flapper mechanism 111 is reduced, the throttle effect of the nozzle flapper mechanism 111 is increased, so that the oil pressure P2 in the second chamber 89 is greater than Ps / 2.
- the aperture amount of the nozzle flapper mechanism 111 is larger than that at the origin position.
- the throttle amount of the nozzle flapper mechanism 111 increases, the throttle effect of the nozzle flapper mechanism 111 decreases, so the oil pressure P2 in the second chamber 89 becomes smaller than Ps / 2.
- the nozzle flapper mechanism 111 is used to The spool 77 reciprocates by adjusting the oil pressure.
- the nozzle flapper mechanism 111 is installed only at the piping 107, that is, at the outlet of the second chamber 89, the flapper 119 is only installed facing one nozzle 113. Therefore, since the position adjustment of the flapper 119 with respect to the nozzle 113 can be easily performed, the installation of the flapper unit 117 can be performed accurately and in a short time. Further, since the circuit configuration of the spool drive circuit 73 is simplified, the processing cost of the valve body can be reduced. Accordingly, the servo valve 71 can be manufactured at low cost.
- the oil supplied from the pump 91 to the first chamber 85 is supplied as it is.
- the first throttle 21 and the pressure adjustment throttle 23 of the first embodiment are omitted, so that the valve body is driven.
- the circuit configuration of the circuit 73 can be further simplified. Since adjustment of the pressure adjustment throttle 23 or the like is not necessary, the adjustment cost can be suppressed. Thereby, the processing cost of the servo valve 71 main body can be further reduced, and the servo valve 71 can be manufactured at a lower cost.
- the first throttle 21 and the pressure adjustment throttle 23 are used as in the first embodiment, the first throttle 21 and the pressure adjustment throttle 23 are isolated from each other.
- the space up to this constitutes a large volume chamber. For this reason, since the spring constant of the oil in this space becomes large, resonance easily occurs.
- the first throttle 21 and the pressure adjustment throttle 23 are not used, resonance can be avoided and the accuracy in driving at a high frequency can be improved.
- the flapper 119 of the nozzle flapper mechanism 111 is operated by the stacked piezoelectric element 121, but is not limited to this.
- a bimorph piezoelectric element that can be driven with a low voltage used in the first embodiment may be used. In this way, a small nozzle flapper mechanism 111 including the power supply portion can be configured.
- the servo valve 71 can be manufactured at a lower cost. For example, it may be operated by a torque motor that performs a linear operation. If it does in this way, the servo valve 71 which can perform the stable adjustment can be comprised by using a torque motor with a track record.
- the first pressure receiving area A1 and the second pressure receiving area A2 are adjusted by the sizes of the cross-sectional areas of the first rod 81 and the second rod 87, but the present invention is not limited to this. .
- the cross-sectional areas of the first rod 81 and the second rod 87 may be the same, and the areas of the land portion 79a and the land portion 79b may be adjusted. Good.
- the first pressure receiving area A1 is set to be approximately half of the second pressure receiving area A2, but the ratio between the first pressure receiving area A1 and the second pressure receiving area A2 is not limited to this. That is, the pressure of the oil in the first chamber 85 is obtained by multiplying the pressure of the oil in the second chamber 89 when the flapper 119 is located at the origin by the second pressure receiving area A2 / the first pressure receiving area A1. What is necessary is just to select the magnitude
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Servomotors (AREA)
- Fuel-Injection Apparatus (AREA)
Abstract
Description
サーボ弁には、弁体として往復作動されるスプ-ルを用いるものがある。このサーボ弁では、スプールを作動させる機構として、たとえば、特許文献1に示されるような、ノズルフラッパ機構が提案されている。
これは、一対のノズルと、この両ノズルの間に設置したフラッパとにより可変オリフィスを形成し、フラッパの位置に応じて変化する両ノズルの背圧を導出し、この導出した背圧の圧力差により、スプールを作動させるものである。
このフラッパの位置変位は、電磁コイルによって行なわれるものが用いられているが、最近では、サーボ弁の小型化および高性能化が求められるので、小型で高速、かつ、発生力が大きい圧電素子(積層型圧電素子、バイモルフ型圧電素子)を用いるものが提案されている。
また、フラッパの両側への移動を正確に行うことが必要であるので、たとえば、積層型圧電素子の場合、フラッパの両側に大きな積層型圧電素子を設けることになる。このため、サーボ弁が大型化するし、フラッパを移動させる制御系のコントロールが難しくなるので、実用に供することが難しい。
さらに、フラッパの位置調整に圧電素子を用いる場合、電極とボディ(弁本体)とが接触すると、過電流が流れてフラッパを作動できなくなるので、確実にそういう事態が発生しないようにすることが求められている。
すなわち、本発明の一態様は、往復動可能に取り付けられた弁体と、該弁体を流体圧によって相互に反対方向に押圧する第一押圧部および第二押圧部と、前記第一押圧部および前記第二押圧部に流体を供給し、かつ、供給する流体の圧力を調節して前記弁体を往復動させる弁体駆動回路を備えているサーボ弁であって、前記弁体駆動回路は、前記第一押圧部の前記流体圧を略一定の大きさに維持するとともに前記第二押圧部からの流体出口部に前記第二押圧部の前記流体圧を調節するノズルフラッパ機構を備えているサーボ弁である。
本態様によれば、第一押圧部の流体圧は略一定の大きさに維持されているので、第二押圧部の流体圧を第一押圧部の流体圧より大きくあるいは小さく調整することによって弁体は往復動する。
第二押圧部からの流体出口部にノズルフラッパ機構が備えられているので、流体出口部に設けられたノズルの先端とフラッパとの間の距離を調整することによって第二押圧部の流体の圧力を調節することができる。第二押圧部の流体の圧力が調整できると、第二押圧部の流体圧が調節できるので、第二押圧部の流体圧は、大きさが一定の第一押圧部の流体圧に対して大きくされたり小さくされたりすることができる。
また、弁体駆動回路の回路構成が単純化されるので、弁本体の加工費を削減することができる。
これらにより、サ-ボ弁を安価に製造することができる。
なお、第一押圧部を略一定の圧力に維持するためには、たとえば、第一押圧部への流体通路に適当な面積を持つ絞りを備える等により流体の圧力を略一定に維持するようにすればよい。
第一受圧面積および第二受圧面積は略同一面積とされているので、第一押圧部および第二押圧部の流体圧の相対的な大きさは、それぞれの流体の圧力によって決定される。
第一押圧部の液体の圧力は、ノズルフラッパ機構によって調整される第二押圧部の流体の圧力範囲における中間部分の中間圧力の大きさになるように選択される。第二押圧部の流体の圧力、言い換えると、第二押圧部の流体圧は、一定に維持される第一押圧部の流体の圧力、言い換えると第一押圧部の流体圧よりも大きくあるいは小さくすることができるので、弁体を往復動することができる。
なお、調節の容易さの観点から第一押圧部の流体の圧力は、ノズルフラッパ機構に電圧をかけない状態における第二押圧部の流体の圧力とノズルフラッパ機構に最大電圧をかけた状態における第二押圧部の流体の圧力の略中間に等しくなるように選択されるのが望ましい。
第一押圧部の流体の圧力は、ノズルフラッパ機構によって調整される第二押圧部の流体の圧力範囲における中間部分の中間圧力に対して第二受圧面積/第一受圧面積を乗じた大きさとなるように選択される。第二押圧部の流体の圧力が中間圧力よりも大きくされると、第二押圧部の流体圧が第一押圧部の流体圧よりも大きくなるので、弁体は第一押圧部の方向に移動される。第二押圧部の流体の圧力が中間圧力よりも小さくされると、第二押圧部の流体圧が第一押圧部の流体圧よりも小さくなるので、弁体は第二押圧部の方向に移動される。
言い換えると、第二押圧部へ供給される流体の中間圧力を供給される流体の圧力に第一受圧面積/第二受圧面積に乗じた大きさとすることによって、第一押圧部の流体の圧力を供給される流体の圧力とすることができるので、第一押圧部へ供給される流体の圧力を調整する部材が不要とできる。
これにより、弁体駆動回路の回路構成が一層単純化されるので、弁本体の加工費を一層削減することができ、サ-ボ弁を一層安価に製造することができる。
このように、変位量が比較的大きく、低電圧で駆動できるバイモルフ型圧電素子を用いるので、電源部分を含めて小さなノズルフラッパ機構を構成することができる。また、バイモルフ型圧電素子は比較的安価であることも相俟って、サーボ弁を一層安価に製造することができる。
フラッパは、1個のノズルに対して距離を調整するので、それを移動させる積層型圧電素子は1個でよい。このため、フラッパの両側にそれぞれ大きな積層型圧電素子を備えるものに比べて小さく構成できるので、サーボ弁を比較的小型化することができる。また、フラッパを移動させる制御系のコントロールも比較的容易となる。
これらにより、実用に供し得るサーボ弁を提供することができる。
実績のあるトルクモータを用いることによって、安定した調整を行えるサーボ弁を構成することができる。
また、弁体駆動回路の回路構成が単純化されるので、弁本体の加工費を削減することができる。
これらにより、サ-ボ弁を安価に製造することができる。
[第一実施形態]
以下、本発明の第一実施形態にかかる油圧アクチュエータの駆動を制御するサーボ弁1について図1~図6を用いて説明する。
図1は、サーボ弁1のスプール駆動回路(弁体駆動回路)3を示す回路図である。図2は、ノズルフラッパ機構の一部を示す部分断面図である。
スプール5は、その軸線方向における位置によって油圧アクチュエータへの作動油の供給方向を切り替える機能を有している。
スプール5の軸線方向位置は、図示しない位置検出器によって検出されるようにされている。
スプール駆動回路3には、油(流体)を供給するポンプ11が備えられている。ポンプ11からの油は、第一通路13と第二通路15とに分岐される。第一通路13を通る油は、第一室7へ供給されるとともにタンク17へ戻される。
第二通路15を通る油は、第二室9に供給された後、配管19に排出される。配管19に排出された油はタンク17に戻される。
第一室7および第二室9の油が作用するスプール5の受圧面積は略同一面積とされている。第一室7および第二室9の油がスプール5に作用する流体圧の差圧は、油の圧力の差圧に比例する。
第一絞り21は、たとえば、オリフィスとされ、第一室7に供給される油の圧力を規定するものである。第一室7に供給される油の圧力P1は、たとえば、ポンプ11から噴出される油の圧力Psの略半分とされている。
圧力調整絞り23は、開口面積が可変とされ、第一室7の油の圧力の大きさを調整する。
第二絞り25は、たとえば、オリフィスとされ、その開口面積は第一絞り21のそれと同じ大きさである。ノズルフラッパ機構27には、第二通路15の下流端に取り付けられたノズル29と、ノズル29の開口部33に対向して設置され、絞りを構成するフラッパ部31とが備えられている。ノズル29は絞り機構であるが、その開口部33の開口面積は、原点位置(フラッパ35に電圧をかけない状態)では、圧力調整絞り23の開口面積と等しくなるため第二室9の油の圧力は、第一室7の油の圧力と等しくなる。
したがって、原点位置における第二室9の油の圧力は、ノズルフラッパ機構27によって調整される範囲の中間部分に位置する中間圧力である。
フラッパ31部には、フラッパ35と、フラッパ35を保持するケース37とが備えられている。ケース37は、金属製で、一面が開放された中空の直方体形状をしている。
フラッパ35は、金属板39の両面に、2枚の板状の圧電素子41,43を貼り合わせた構成、すなわち、バイモルフ型圧電素子で構成されている。
フラッパ35の一端部は、ケース37の内部空間に挿入され、電線45とともに接着材47によってケース37に固定されている。接着材47は、電気絶縁性を有する樹脂で、たとえば、エポキシ樹脂等のモールド剤が用いられる。
フラッパ35は、この限界位置とフラッパ35およびノズル29が接触する位置との中間に位置するように設置され、その位置を中心にして、限界位置とフラッパ35およびノズル29が接触する位置との間を変位するようにされている。
まず、金属板39の両面に、板状の圧電素子41,43を貼り付ける。
次いで、金属板39および圧電素子41,43の一端に電線45を、たとえば、ハンダによって接合する。
次に、図4に示されるように、金属板39および圧電素子41,43と電線45との接点の周辺部分を接着材47によって固定し、フラッパ35を形成する。
このとき、接着材47は量が少ないので、電線45を変形させる等の事態を引き起こすことはない。すなわち、接点が離脱する、電線45がケースに接触するような形に変形することがない。
次いで、図5に示されるように、このフラッパ35をケース37の所定位置に組み込み、ケース37の内部空間に接着材47を注入する。
この接着材47の注入によってフラッパ35には大きな力が作用するが、金属板39および圧電素子41,43と電線45との接点は、先の硬化した接着材47によって保護されているので、それらが離脱することはない。また、電線45の可動部分も長くないので、ケース37に接触するほど大きく変形することはない。
このとき、ケース37の先端面51とフラッパ35の面とが直交することが重要であるので、図6に示されるように直交状態を保持する第一治具53および第二治具55に設置して養生を行うようにしてもよい。
第一治具53は、断面が矩形状をした貫通孔57を有している。貫通孔57の一端部には、ケース37の先端面51が貫通孔と直交するように設置できる拡大部が設けられている。
貫通孔57と、貫通孔59とは、上下方向の中心位置が一致している。
ケース37をフラッパ35側から貫通孔57に挿入し、拡大部にはめ込む。次いで、第二治具55を貫通孔57の反対側から挿入し、フラッパ35の先端部を貫通孔59に挿入させる。このようにすると、ケース37の先端面51とフラッパ35の面とが直交することになる。
この状態で、養生すると、接着材47が硬化し、フラッパ35は、ケース37の先端面51とフラッパ35の面とが直交する形でケース37に固定される。
ポンプ11が作動され、油が供給されると、供給された油は分岐されて第一通路13および第二通路15に流れ込む。第一通路13に流れ込んだ油は、第一絞り21で減圧され、第一室7に流入するとともに圧力調整絞り23を通ってタンク17に戻される。
第二通路15に流入した油は、第二絞り25で減圧され、第二室9に流入する。油は第二室9からノズルフラッパ機構27を通って配管19に排出され、配管19からタンク17に戻される。
ノズルフラッパ機構27の絞り量が小さくなると、ノズルフラッパ機構27の絞り効果がノズル29のそれよりも大きくなるので、第一室7よりも第二室9の圧力が大きくなり、第一室7と第二室9との間に差圧が生じる。この差圧によってスプール5は第一室7側に移動する。
ノズルフラッパ機構27の絞り量が圧力調整絞り23よりも大きくなると、第一室7よりも第二室9の圧力が小さくなり、第一室7と第二室9との間に差圧が生じる。この差圧によってスプール5は第二室9側に移動する。
このように、第一室7に供給される油の圧力は略一定の大きさに維持されているので、ノズルフラッパ機構27を用いて第二室9の圧力を第一室7の圧力より大きくあるいは小さく調整することによってスプール5は往復動する。
また、スプール駆動回路3の回路構成が単純化されるので、弁本体の加工費を削減することができる。
これらにより、サ-ボ弁1を安価に製造することができる。
フラッパ35は、1個のノズル29に対して距離を調整するので、それを移動させる積層型圧電素子61は1個でよい。
このため、フラッパ35の両側にそれぞれ大きな積層型圧電素子61を備えるものに比べて小さく構成できるので、サーボ弁1を比較的小型化することができる。
また、フラッパ35を移動させる制御系のコントロールも比較的容易となる。
これらにより、積層型圧電素子61を用いても実用に供し得るサーボ弁1を提供することができる。
このようにすると、実績のあるトルクモータ63を用いることによって、安定した調整を行えるサーボ弁1を構成することができる。
本発明の第二実施形態にかかる油圧アクチュエータ(図示省略)の駆動を制御するサーボ弁71について図9~図12を用いて説明する。
図9は、サーボ弁71のスプール駆動回路(弁体駆動回路)73を示す回路図である。図10は、ノズルフラッパ機構の一部を示す部分断面図である。図11は、図9のX-X断面図である。図12は、図9のY-Y断面図である。
スプール77には、滑り面となる略同一の径を有する複数のランド部79が備えられている。スプール77が軸線方向に移動することによってこれらのランド部79の軸線方向における位置が移動する。これらのランド部79は、軸線方向の位置によって図示しない油圧アクチュエータへの作動油の供給方向を切り替える機能を有している。
スプール77の一端部分に設けられたランド部79aには、外側に向けて突設された第一棒体81が設けられている。第一棒体81はその動作を差動変圧器83に伝達する。差動変圧器83は、スプール77の軸線方向位置を検出する。
スプール77の他端部分に設けられたランド部79bには、外側に向けて突設された第二棒体87が設けられている。ランド部79bの外側に、第二棒体87を包囲するように第二室(第二押圧部)89が形成されている。
主通路93は、第一通路97と第二通路99とに分岐される。第一通路97を通る油は、第一室85へ供給され、配管101を経由して戻り通路103を通ってタンク105へ戻される。第一室85には、主通路93で供給される油がそのまま供給されている。この供給される油の圧力は、ポンプ91が噴出する圧力Psである。
第二通路99を通る油は、第二室89に供給された後、配管107を経由して戻り通路103を通ってタンク105へ戻される。
第二棒体87は第二室89を貫通しているので、ランド部79bが第二室89に供給された油から圧力を受ける第二受圧面積A2は、図12に示されるようにランド部79bの面積から第二棒体87の断面積を減じた大きさとなる。
本実施形態では、第一受圧面積A1が第二受圧面積A2の略半分の大きさとなるように第一棒体81および第二棒体87の大きさが設定されている。
なお、第一受圧面積A1および第二受圧面積A2の面積比は、これに限定されるものではない。
ノズルフラッパ機構111には、配管107に取り付けられたノズル113と、ノズル113の開口部115に対向して設置され、絞りを構成するフラッパ部117とが備えられている。
フラッパ部117には、フラッパ119と、フラッパ35を作動させる複数の圧電素子が積層された積層型圧電素子121とが備えられている。
この側面積が開口部115の開口面積と等しくなる位置(図10の状態)はノズルフラッパ機構111が絞り機能を奏する限界位置である。すなわち、フラッパ119がこの位置よりもノズル113から離れると絞り効果がノズル113の絞り効果よりも小さくなるので、ノズルフラッパ機構111は絞り機能を奏さないことになる。
本実施形態では、フラッパ119が原点位置にあるとき、第一室85の油の圧力P1は、ポンプ91が供給する圧力Psと略同一の大きさとなるようにノズルフラッパ111の諸元が設定されている。
ポンプ91が作動されると、タンク105から主通路93を通って油が供給される。この供給される油の圧力Psは、圧力調整弁95によって略一定に維持されている。
主流路93を流れる油は分岐されて第一通路97および第二通路99に流れ込む。
第一通路97に流れ込んだ油は、そのまま第一室85に流入し、配管101および戻り通路103を通ってタンク105に戻される。
第二通路99に流入した油は、入口絞り109で減圧され、第二室89に流入する。油は第二室89から配管107に排出され、ノズルフラッパ機構111を通って戻り通路103からタンク105に戻される。
一方、第二室89の油の圧力P2は、ポンプ91が供給する圧力Psの略半分、すなわち、P2=Ps/2である。第二室89の油がランド部79bに作用する力(流体圧)F2は、F2=A2×Ps/2となる。
A2=2×A1であるので、力F2は、F2=2×A1×Ps/2=A1×Psとなる。力F1と力F2とは同じ大きさとなるので、両者の差圧は0になる。この差圧0の状態ではスプール77は停止状態となる。
ノズルフラッパ機構111の絞り量が小さくなると、ノズルフラッパ機構111の絞り効果が大きくなるので、第二室89の油の圧力P2は、Ps/2よりも大きくなる。
圧力P2が大きくなると、第二室89の油がランド部79bに作用する力F2が大きくなるので、力F2は大きさ一定の第一室85の力F1よりも大きくなる。
この差圧によってスプール77は第一室85側に移動する。
ノズルフラッパ機構111の絞り量が大きくなると、ノズルフラッパ機構111の絞り効果が小さくなるので、第二室89の油の圧力P2は、Ps/2よりも小さくなる。
圧力P2が小さくなると、第二室89の油がランド部79bに作用する力F2が小さくなるので、力F2は大きさ一定の第一室85の力F1よりも小さくなる。
この差圧によってスプール77は第二室89側に移動する。
したがって、ノズル113に対するフラッパ119の位置調整を容易に行うことができるので、フラッパ部117の設置が正確に、かつ、短時間に行うことができる。
また、スプール駆動回路73の回路構成が単純化されるので、弁本体の加工費を削減することができる。
これらにより、サ-ボ弁71を安価に製造することができる。
これにより、サーボ弁71本体の加工費を一層削減することができ、サ-ボ弁71を一層安価に製造することができる。
たとえば、第一実施形態で用いた低電圧で駆動できるバイモルフ型圧電素子を用いてもよい。このようにすると、電源部分を含めて小さなノズルフラッパ機構111を構成することができる。バイモルフ型圧電素子は比較的安価であることも相俟って、サーボ弁71を一層安価に製造することができる。
たとえば、リニア動作を行うトルクモータによって作動されるようにしてもよい。
このようにすると、実績のあるトルクモータを用いることによって、安定した調整を行えるサーボ弁71を構成することができる。
たとえば、図13および図14に示されるように、第一棒体81および第二棒体87の断面積の大きさを同じとし、ランド部79aおよびランド部79bの面積を調整するようにしてもよい。
すなわち、第一室85の油の圧力が、フラッパ119が原点に位置しているときの第二室89の油の圧力に対して第二受圧面積A2/第一受圧面積A1を乗じた大きさとなるように各圧力ならびに第一受圧面積A1および第二受圧面積A2の大きさを選定すればよい。
3 スプール駆動回路
5 スプール
7 第一室
9 第二室
35 フラッパ
61 積層型圧電素子
63 トルクモータ
71 サーボ弁
73 スプール駆動回路
77 スプール
85 第一室
89 第二室
119 フラッパ
121 積層型圧電素子
Claims (6)
- 往復動可能に取り付けられた弁体と、該弁体を流体圧によって相互に反対方向に押圧する第一押圧部および第二押圧部と、前記第一押圧部および前記第二押圧部に流体を供給し、かつ、供給する流体の圧力を調節して前記弁体を往復動させる弁体駆動回路と、を備えているサーボ弁であって、
前記弁体駆動回路は、前記第一押圧部の前記流体圧を略一定の大きさに維持するとともに前記第二押圧部の流体出口部に前記第二押圧部の前記流体圧を調節するノズルフラッパ機構を備えているサーボ弁。 - 前記弁体における前記第一押圧部の流体が前記弁体に作用する第一受圧面積と、前記第二押圧部の流体が前記弁体に作用する第二受圧面積と、が略同一面積とされている請求項1に記載のサーボ弁。
- 前記弁体における前記第一押圧部の流体が前記弁体に作用する第一受圧面積と、前記第二押圧部の流体が前記弁体に作用する第二受圧面積と、が異なる面積とされている請求項1に記載のサーボ弁。
- 前記ノズルフラッパ機構のフラッパは、バイモルフ型圧電素子によって作動される請求項1から請求項3のいずれか1項に記載のサーボ弁。
- 前記ノズルフラッパ機構のフラッパは、積層型圧電素子によって作動される請求項1から請求項3のいずれか1項に記載のサーボ弁。
- 前記ノズルフラッパ機構のフラッパは、トルクモータによって作動される請求項1から請求項3のいずれか1項に記載のサーボ弁。
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN2009801301588A CN102112754A (zh) | 2008-08-08 | 2009-05-29 | 伺服阀 |
EP09804801.0A EP2309135A4 (en) | 2008-08-08 | 2009-05-29 | SERVO-VALVE |
KR1020137016509A KR101335213B1 (ko) | 2008-08-08 | 2009-05-29 | 서보 밸브 |
US13/057,615 US20120216896A1 (en) | 2008-08-08 | 2009-05-29 | Servo valve |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2008-206370 | 2008-08-08 | ||
JP2008206370 | 2008-08-08 | ||
JP2009-105444 | 2009-04-23 | ||
JP2009105444A JP5232714B2 (ja) | 2008-08-08 | 2009-04-23 | サーボ弁 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2010016314A1 true WO2010016314A1 (ja) | 2010-02-11 |
Family
ID=41663539
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2009/059859 WO2010016314A1 (ja) | 2008-08-08 | 2009-05-29 | サーボ弁 |
Country Status (6)
Country | Link |
---|---|
US (1) | US20120216896A1 (ja) |
EP (1) | EP2309135A4 (ja) |
JP (1) | JP5232714B2 (ja) |
KR (2) | KR20110020949A (ja) |
CN (1) | CN102112754A (ja) |
WO (1) | WO2010016314A1 (ja) |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5781330B2 (ja) * | 2011-02-28 | 2015-09-24 | 三菱重工業株式会社 | 内燃機関の動弁装置 |
US9739393B2 (en) | 2014-02-05 | 2017-08-22 | Pentair Flow Control Ag | Valve controller with flapper nozzle pilot valve |
JP6278558B2 (ja) * | 2014-02-27 | 2018-02-14 | 三菱重工機械システム株式会社 | パイロット圧調整装置、サーボ弁、および、アクチュエータ |
FR3063279B1 (fr) * | 2017-02-24 | 2019-04-19 | Safran Landing Systems | Servovalve de regulation de pression a debit de fuite reduit |
EP3502486B1 (en) | 2017-12-22 | 2020-10-28 | Hamilton Sundstrand Corporation | Servo valve |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS483270B1 (ja) * | 1969-07-12 | 1973-01-30 | ||
JPS6139111A (ja) * | 1984-07-31 | 1986-02-25 | Tokyo Keiki Co Ltd | 位置追従式比例ソレノイド形スプ−ル弁 |
JPH06109158A (ja) * | 1991-02-14 | 1994-04-19 | Mannesmann Rexroth Gmbh | 流体機械用のノズル装置 |
JPH0754672A (ja) * | 1993-08-11 | 1995-02-28 | Ishikawajima Harima Heavy Ind Co Ltd | タービンの燃料流量制御装置 |
JP2001082411A (ja) * | 1999-09-17 | 2001-03-27 | Japan Science & Technology Corp | ディジタル弁 |
Family Cites Families (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2972999A (en) * | 1955-11-01 | 1961-02-28 | Sanders Associates Inc | Two-stage, differential, hydraulic servo valve |
US2962002A (en) * | 1956-04-10 | 1960-11-29 | Sanders Associates Inc | Two-stage hydraulic servo valve |
US3152612A (en) * | 1956-09-28 | 1964-10-13 | Gen Electric | Piezoelectric crystal transducer for controlling fluid flow |
DE1069972B (ja) * | 1957-01-30 | 1959-11-26 | ||
US3447555A (en) * | 1965-05-24 | 1969-06-03 | Bell Aerospace Corp | Hydraeric position monitoring apparatus |
US3555970A (en) * | 1968-08-08 | 1971-01-19 | Bell Aerospace Corp | Pressure regulator for servo valve having dynamic load adaptive response |
US4617952A (en) * | 1984-07-31 | 1986-10-21 | Yamatake-Honeywell Co. Limited | Switching valve and an electro-pneumatic pressure converter utilizing the same |
FR2583115B1 (fr) * | 1985-06-10 | 1989-03-10 | Centre Techn Ind Mecanique | Transducteur electrofluidique du type buse/palette et servovalve hydraulique equipee d'un tel transducteur |
GB8717637D0 (en) * | 1987-07-24 | 1987-09-03 | Lucas Ind Plc | Fluid metering valve |
JPH0366988A (ja) * | 1989-08-04 | 1991-03-22 | Nippon Muugu Kk | プレッシャー・スイッチ・マニホールド |
US6755205B1 (en) * | 2002-09-12 | 2004-06-29 | Woodward Governor Company | Method to stabilize a nozzle flapper valve |
DE102004023553B3 (de) * | 2004-05-13 | 2006-01-26 | Danfoss A/S | Hydraulik-Ventilanordnung, insbesondere Wasserhydraulik-Ventilanordnung |
FR2873828B1 (fr) * | 2004-07-27 | 2006-10-20 | In Lhc Soc Par Actions Simplif | Servovalve de regulation de pression a debit de fuite reduit |
US20060232166A1 (en) * | 2005-04-13 | 2006-10-19 | Par Technologies Llc | Stacked piezoelectric diaphragm members |
US8082952B2 (en) * | 2008-08-22 | 2011-12-27 | Hamilton Sundstrand Corporation | Piezoelectric bending element actuator for servo valve |
-
2009
- 2009-04-23 JP JP2009105444A patent/JP5232714B2/ja active Active
- 2009-05-29 EP EP09804801.0A patent/EP2309135A4/en not_active Withdrawn
- 2009-05-29 KR KR1020117002314A patent/KR20110020949A/ko active Application Filing
- 2009-05-29 CN CN2009801301588A patent/CN102112754A/zh active Pending
- 2009-05-29 WO PCT/JP2009/059859 patent/WO2010016314A1/ja active Application Filing
- 2009-05-29 KR KR1020137016509A patent/KR101335213B1/ko active IP Right Grant
- 2009-05-29 US US13/057,615 patent/US20120216896A1/en not_active Abandoned
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS483270B1 (ja) * | 1969-07-12 | 1973-01-30 | ||
JPS6139111A (ja) * | 1984-07-31 | 1986-02-25 | Tokyo Keiki Co Ltd | 位置追従式比例ソレノイド形スプ−ル弁 |
JPH06109158A (ja) * | 1991-02-14 | 1994-04-19 | Mannesmann Rexroth Gmbh | 流体機械用のノズル装置 |
JPH0754672A (ja) * | 1993-08-11 | 1995-02-28 | Ishikawajima Harima Heavy Ind Co Ltd | タービンの燃料流量制御装置 |
JP2001082411A (ja) * | 1999-09-17 | 2001-03-27 | Japan Science & Technology Corp | ディジタル弁 |
Also Published As
Publication number | Publication date |
---|---|
JP5232714B2 (ja) | 2013-07-10 |
JP2010060128A (ja) | 2010-03-18 |
KR101335213B1 (ko) | 2013-11-29 |
EP2309135A1 (en) | 2011-04-13 |
US20120216896A1 (en) | 2012-08-30 |
CN102112754A (zh) | 2011-06-29 |
KR20130100188A (ko) | 2013-09-09 |
KR20110020949A (ko) | 2011-03-03 |
EP2309135A4 (en) | 2013-12-11 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5232714B2 (ja) | サーボ弁 | |
KR101328280B1 (ko) | 유압 조정 밸브 | |
KR102332033B1 (ko) | 연료 분사기 | |
US20030213523A1 (en) | Directly operated pneumatic valve having an air assist return | |
JP4697043B2 (ja) | 流体圧制御装置 | |
CN1776214B (zh) | 带有柱塞电磁激励的燃料喷射器 | |
WO2009158632A1 (en) | Distributed stiffness biasing spring for actuator system and fuel injector using same | |
US20100007224A1 (en) | Precision ground stator assembly for solenoid actuator and fuel injector using same | |
US20160160886A1 (en) | Improvements in hydraulic servovalves | |
CN102405344A (zh) | 用于喷射阀的阀组件和喷射阀 | |
JP2012229812A (ja) | サーボ弁 | |
KR20140022457A (ko) | 밸브 조립체 및 이를 포함하는 연료 펌프 | |
CA2829146C (en) | Improvements in servovalve actuation | |
JP2000277327A (ja) | リニアソレノイド及びそれを用いた電磁弁 | |
JP4492649B2 (ja) | ブリード式バルブ装置 | |
US20070075283A1 (en) | Valve apparatus | |
JP4301318B2 (ja) | ブリード式バルブ装置 | |
KR100698894B1 (ko) | 압전밸브 | |
JP6038661B2 (ja) | ソレノイドバルブ | |
JP5955763B2 (ja) | 弁構造 | |
JP4537157B2 (ja) | アキュムレータ燃料噴射系用の調圧弁 | |
KR20120001036U (ko) | 3포트 압전 밸브 | |
US20080156383A1 (en) | Fluid-transfer system | |
WO2015097870A1 (ja) | 電磁弁 | |
WO2020136025A1 (en) | A fuel flow path for a valve group of a fuel injector |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 200980130158.8 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 09804801 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 20117002314 Country of ref document: KR Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 13057615 Country of ref document: US |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2009804801 Country of ref document: EP |
|
NENP | Non-entry into the national phase |
Ref country code: DE |