CN209925694U - Piezoelectric driving type rotary valve - Google Patents

Abstract

The utility model discloses a piezoelectricity drive formula changes valve. The valve sleeve component is arranged in a cylindrical hole in the center of the valve body component, the valve core component is nested in the cylindrical hole of the valve sleeve component, and the piezoelectric driving component is arranged on the upper end surface of the valve sleeve component and is nested and connected with the upper end of the valve core component; the piezoelectric driving component comprises an eccentric pin shaft and two groups of piezoelectric rotary driving groups. The utility model provides high change the dynamic and static performance of valve has that operating pressure is high, the through-flow capacity is big, control accuracy is high, the response is fast, the antipollution ability is strong and advantages such as high reliability, can greatly widen the range of application of single-stage valve and commentaries on classics valve, uses extensively.

Description

Piezoelectric driving type rotary valve

Technical Field

The utility model relates to a direction, flow control valve in hydraulic drive control field have especially related to a piezoelectricity drive formula changes valve.

Background

With the development of the economic society, modern mechanical equipment is developing towards large-scale and intelligentized directions, and the application of the hydraulic transmission control technology is increasing day by day. However, the conventional hydraulic control valve generally adopts an electromagnetic electromagnet, a force motor or a torque motor to drive a valve core to linearly move along the axial direction of the valve core, so as to control the pressure and the flow.

SUMMERY OF THE UTILITY MODEL

In order to overcome the through-flow ability that electromagnetic drive formula control valve especially single-stage valve has poor, the frequency response is low and shortcoming such as antipollution ability is poor, satisfy requirements such as modern mechanical equipment is to high pressure large-traffic, high accuracy, high frequency response and high reliability of hydraulic control valve, the utility model provides a piezoelectric drive formula rotary valve.

In order to achieve the above object, the utility model provides a following technical scheme:

the utility model discloses a valve body subassembly, valve barrel subassembly, case subassembly and piezoelectricity drive assembly, valve barrel unit mount are downthehole in the cylinder at valve body subassembly center, and the case subassembly is nested to be installed in the cylinder of valve barrel subassembly downthehole, and piezoelectricity drive assembly installs in the up end of valve barrel subassembly to with the nested hookup in case subassembly upper end.

The valve body assembly comprises a valve body, a lower end cover and an upper end cover, wherein the valve body is hollow to form a mounting cylindrical cavity, the lower end cover is mounted on the lower end face of the valve body, and the upper end cover is mounted on the upper end face of the valve body; four valve openings are arranged on the outer wall of the valve body and respectively used as a valve port A, a valve port P, a valve port B and a valve port T.

The valve sleeve assembly comprises a valve sleeve and a spring seat, the valve sleeve is fixedly sleeved in an installation cylindrical cavity of the valve body, the valve sleeve is sequentially provided with five through holes along the axial direction, and the five through holes are respectively a first oil return port, a working oil port A, a high-pressure oil port P, a working oil port B and a second oil return port from top to bottom; the spring seat is coaxially arranged on the upper end face of the valve sleeve and is axially limited and fixed by the upper end cover, and the spring seat is used for supporting the first blocking cover, the second blocking cover and the spring of the valve core assembly.

The valve core assembly comprises a valve core, a spring, a first blocking cover and a second blocking cover, the valve core is movably sleeved on the valve sleeve, the top end of the valve core sequentially penetrates through the valve sleeve, the spring seat and the upper end cover upwards and then is connected with the piezoelectric driving assembly, the first blocking cover, the second blocking cover and the spring are sleeved outside a shaft section extending out between the spring seat and the upper end cover at the top end of the valve core, and two ends of the spring are respectively connected with the first blocking cover and the second blocking cover; a spring cavity is formed in the upper end cover between the first blocking cover and the second blocking cover, and the spring cavity is communicated with the valve port P through a channel in the upper end cover and the valve body.

The piezoelectric driving assembly comprises an eccentric pin shaft and two groups of piezoelectric rotation driving groups, the eccentric pin shaft is sleeved at the top end of the valve core, the top end of the valve core is a square shaft, the eccentric pin shaft is provided with an eccentric square hole, the square shaft of the valve core is sleeved in the square hole, and the two groups of piezoelectric rotation driving groups have the same structure and are symmetrically arranged at two sides of the eccentric pin shaft; the group of piezoelectric rotary driving groups comprises a first support frame, a first piezoelectric actuator, a first shaft sleeve, a first fisheye joint and a first pin shaft, wherein the inner end of the first support frame, which is close to the eccentric pin shaft, is fixed on the upper end cover; the other group of piezoelectric rotation driving groups comprise a second support frame, a second piezoelectric actuator, a second shaft sleeve, a second fisheye joint and a second pin shaft; the inner end of the second support frame, which is close to the eccentric pin shaft, is fixed on the upper end cover, the second pin shaft is installed at the edge of the outer end of the second support frame, which is far away from the eccentric pin shaft, the inner end of the second piezoelectric actuator is hinged with the eccentric pin shaft through a second shaft sleeve, and the outer end of the second piezoelectric actuator is hinged with the second pin shaft through a second fisheye joint.

The inner end of the first piezoelectric actuator is fixedly connected with one end of the first shaft sleeve through a threaded hole and a threaded shaft, the other end of the first shaft sleeve is sleeved outside the eccentric pin shaft, and the other end of the first shaft sleeve is connected with the arc surface of the eccentric pin shaft to form hinge joint; the outer end of the first piezoelectric actuator is fixedly connected with one end of the first fisheye joint through a threaded hole and a threaded shaft, the other end of the first fisheye joint is sleeved on the first pin shaft, and the other end of the first fisheye joint is connected with the first pin shaft through the arc surface to form hinge joint.

The inner end of the second piezoelectric actuator is fixedly connected with one end of the second shaft sleeve through a threaded hole and a threaded shaft, the other end of the second shaft sleeve is sleeved outside the eccentric pin shaft, and the other end of the second shaft sleeve is connected with the arc surface of the eccentric pin shaft to form a hinge joint; the outer end of the second piezoelectric actuator is fixedly connected with one end of a second fisheye joint through a threaded hole and a threaded shaft, the other end of the second fisheye joint is sleeved on a second pin shaft, and the other end of the second fisheye joint is connected with the second pin shaft through an arc surface to form hinge joint.

The center of a square hole of the eccentric pin shaft is away from the central axis of the outer cylindrical surface by an eccentricity e, so that the first piezoelectric actuator, the first shaft sleeve, the eccentric pin shaft, the valve core, the valve sleeve, the first fisheye joint, the first pin shaft and the first support frame form a crank link mechanism, and the first piezoelectric actuator extends to push the eccentric pin shaft to rotate around the center of the square shaft of the valve core so as to drive the valve core to rotate around a first direction; and the second piezoelectric actuator, the second shaft sleeve, the eccentric pin shaft, the valve core, the valve sleeve, the second fisheye joint, the second pin shaft and the second support frame form a crank-link mechanism, and the second piezoelectric actuator extends to push the eccentric pin shaft to rotate around the center of the square shaft of the valve core so as to drive the valve core to rotate around the second direction.

The first direction and the second direction are both clockwise or anticlockwise, but the first direction and the second direction are opposite.

The positions of the first shaft sleeve and the second shaft sleeve in the two piezoelectric rotation driving groups, which are sleeved on the eccentric pin shaft, are staggered, so that the rotation of the first shaft sleeve relative to the eccentric pin shaft and the rotation of the second shaft sleeve relative to the eccentric pin shaft do not interfere.

The outer wall of the bottom of the valve core is provided with a first spiral groove and a second spiral groove, the first spiral groove and the second spiral groove are both grooves which are not communicated with the side wall, and the bottom end face of the valve core is provided with a first oil duct and a second oil duct which are axially arranged; the first spiral groove is communicated with the first oil duct through a channel in the valve core, and the second spiral groove is communicated with the second oil duct through a channel in the valve core; one end of the first oil duct, which is positioned at the bottom end of the valve core, is sealed by a plug, and the other end of the first oil duct is communicated with the annular groove, which is closest to the bottom end, of the three annular grooves of the valve core; the second oil duct is closed at one end at the bottom end of the valve core through a plug, and the second oil duct is communicated with the annular groove in the middle of the three annular grooves of the valve core; three annular grooves are formed in the middle of the valve core, two outer flanges are formed between the three annular grooves, a first step and a second step which are used for being matched with each oil port on the valve sleeve are formed on the outer peripheral surfaces of the two outer flanges respectively, and the periodic interval between the first step and the second step is the same as the periodic interval between every two adjacent oil ports of the valve sleeve; the side wall of the bottom of the valve sleeve is provided with a third spiral groove, the third spiral groove is a through groove penetrating through the side wall, the third spiral groove is communicated with the bottom sensitive cavity, the edge of the side wall of the valve sleeve close to the bottom end is provided with a radial oil hole, and the radial oil hole is a through hole penetrating through the side wall; and a cylindrical cavity is arranged between the bottom end of the valve core and the lower end cover and serves as a sensitive cavity.

The first spiral groove, the second spiral groove and the third spiral groove have the same rotating direction, thread pitch and groove width, and the periodic interval between the first spiral groove and the second spiral groove is half of the thread pitch of the third spiral groove; in any case, only one of the first and second helical grooves communicates with the third helical groove, i.e. the first and second helical grooves do not communicate with the third helical groove at the same time.

A main valve port PA is formed between the upper edge of the first step of the valve core and the working oil port A, a main valve port AT is formed between the lower edge of the first step of the valve core and the working oil port A, a main valve port PB is formed between the lower edge of the second step of the valve core and the working oil port B, and a main valve port BT is formed between the upper edge of the second step of the valve core and the working oil port B; the valve core moves along the axial direction under the action of hydraulic pressure of spring cavity high-pressure oil and sensitive cavity pressure oil and the action of spring force, and the opening and size control of a main valve port PA, a main valve port PB, a main valve port AT and a main valve port BT between the valve core and the valve sleeve are realized.

The utility model discloses a piezoceramics and crank link mechanism drive valve core reciprocating rotation to utilize the pressure in the sensitive chamber of hydraulic control bridge circuit control that two helical flutes on case and the valve barrel constitute, and then drive the valve core along its axial direction reciprocating motion, turn into the linear motion of big stroke with the rotary motion of small angle, control the size of main valve mouth, thereby realize the control to the direction and the size of hydraulic circuit pressure and flow. The piezoelectric driving device has the characteristics of large output force, high control precision, quick response and the like, and can effectively resist the influence of interference factors such as hydrodynamic force, friction force, clamping force and the like on the valve core, so the through-flow capacity and the reliability of the hydraulic control valve, particularly the single-stage valve, can be greatly improved, the piezoelectric driving device has the advantages of simple structure, high working pressure, high through-flow capacity, high control precision, quick response, strong pollution resistance, high reliability and the like, can greatly widen the application range of the single-stage valve and the rotary valve, is widely applied to the fields of automobiles, marine ships, aerospace, metallurgy and the like, and improves the control characteristic of a high-pressure large-flow hydraulic system, particularly a proportional servo system and the intellectualization and reliability level of modern intelligent equipment.

Piezoelectric drive formula rotary valve is applicable to the regulation of high-pressure large-traffic hydraulic system's pressure and flow direction and size to realize that modern intelligence equips the control of output power, displacement and speed (or moment, angle displacement and angular velocity).

The beneficial effects of the utility model reside in that:

the utility model discloses a piezoelectric drive device passes through crank link mechanism and drives case reciprocating rotation, and utilize the hydraulic control bridge circuit that two spiral grooves on case and the valve barrel constitute to carry out power and displacement's amplification, thereby the size of control main valve mouth, can effectively resist hydrodynamic force, interference factors such as frictional force and chucking power are to the influence of case, improve the through-flow capacity and the reliability of hydraulic control valve especially single-stage valve, make it have simple structure, the operating pressure is high, the through-flow capacity is big, control accuracy is high, the response is fast, advantages such as anti-pollution ability reinforce and high reliability, can greatly widen the range of application of single-stage valve and commentaries on classics valve.

The utility model discloses especially, can solve large-scale, heavy equipment fields such as car, ocean vessel, aerospace and metallurgy, improve high pressure, large-traffic hydraulic system especially dynamic and static control characteristics such as proportional servo's control accuracy and frequency response, reduce the maintenance cost, promote the intellectuality and the reliability level that modern intelligence was equipped.

Drawings

Fig. 1 is a schematic view of the overall appearance of the present invention.

Fig. 2 is an exploded view of the main components of the present invention.

Fig. 3 is a schematic overall main sectional view of the present invention.

Fig. 4 is a schematic sectional view of the whole a-a cross section of the present invention.

Fig. 5(a) is a sectional view of a piezoelectric driving unit B-B according to the present invention.

Fig. 5(b) is a partially enlarged schematic view of fig. 5 (a).

Fig. 6 is a schematic view of the valve core structure of the present invention.

Fig. 6(a) is a sectional view of the valve element of the present invention.

Fig. 6(b) is a side view of the valve cartridge of the present invention.

Fig. 6(c) is a schematic view of the bottom end surface of the valve core of the present invention.

Fig. 7 is a schematic sectional view of the valve sleeve of the present invention.

Fig. 7(a) is a sectional view of the valve sleeve of the present invention.

Fig. 7(b) is a side view of the valve sleeve of the present invention.

Fig. 7(c) is a schematic view of the bottom end surface of the valve sleeve of the present invention.

Fig. 8 is a schematic view of the valve core and the valve sleeve of the present invention in different working states.

Fig. 8(a1) is a cross-sectional view of the closed valve state of the present invention.

Fig. 8(a2) is a side view of the exterior of the valve housing in the closed valve position of the present invention.

Fig. 8(b1) is a sectional view showing the PA communication state and the BT communication state according to the present invention.

Fig. 8(b2) is an external side view of the valve sleeve in the PA communication state and the BT communication state according to the present invention.

Fig. 8(c1) is a sectional view showing the PB communication and the AT communication according to the present invention.

Fig. 8(c2) is a side view of the outside of the valve sleeve with the PB and AT open positions.

Fig. 9 is a schematic diagram of the motion of the crank link mechanism of the present invention.

FIG. 10 is a schematic diagram of the hydraulic control bridge of the present invention.

In the drawings: 1. a piezoelectric drive assembly; 2. a valve body assembly; 3. a valve core assembly; 4. a valve housing assembly; 5. a first pin shaft; 6. a first fisheye joint; 7. a first support frame; 8. a first piezoelectric actuator; 9. a first bushing; 10. an eccentric pin shaft; 11. a second shaft sleeve; 12. a second support frame; 13. a second piezoelectric actuator; 14. a second fisheye joint; 15. a second pin shaft; 16. a spring seat; 17. a valve core; 18. a valve housing; 19. a valve body; 20. a lower end cover; 21. a first shield cover; 22. an upper end cover; 23. a spring; 24. a second shield cover; 25. a first helical groove; 26. a second helical groove; 27. a first oil passage; 28. a second oil passage; 29. a first step; 30. a second step; 31. a radial oil hole; 32. a third helical groove; 33. a first oil return port; 34. a working oil port A; 35. a high-pressure oil port P; 36. a working oil port B; 37. a second oil return port; 38. a control valve port PC; 39. a main valve port PA; 40. a main valve port BT; 41. controlling a valve port CT; 42. a main valve port AT; 43. a main valve port PB; 44. a spring cavity; 45. a sensitive cavity; 46. a valve port T; 47. a valve port A; 48. a valve port P; 49. and a valve port B.

Detailed Description

The present invention will be further described with reference to fig. 1 to 8.

As shown in fig. 1, the utility model discloses the implementation includes valve body subassembly 2, valve barrel subassembly 4, case subassembly 3 and piezoelectricity drive assembly 1, and valve barrel subassembly 4 is installed in the cylinder hole at valve body subassembly 2 center, and the nested installation of case subassembly 3 is in the cylinder hole of valve barrel subassembly 4, and piezoelectricity drive assembly 1 installs in the up end of valve barrel subassembly 4 to with the nested hookup in case subassembly 3 upper end. After the assembly, the whole appearance schematic diagram of the piezoelectric driving rotary valve of the utility model is shown in figure 2.

As shown in fig. 3 and 4, the valve body assembly 2 includes a valve body 19, a lower end cap 20 and an upper end cap 22, the valve body 19 is hollow to form a mounting cylindrical cavity, the lower end cap 20 is mounted on the lower end surface of the valve body 19, and the upper end cap 22 is mounted on the upper end surface of the valve body 19 for sealing and supporting other components; the outer wall of the valve body 19 is provided with four valve holes which are respectively used as a valve port A47, a valve port P48, a valve port B49 and a valve port T46;

the valve sleeve assembly 4 comprises a valve sleeve 18 and a spring seat 16, the valve sleeve 18 is fixedly sleeved in an installation cylindrical cavity of the valve body 19, the outer wall of the valve sleeve 18 is in sealing contact connection with the inner wall of the valve body 19 through a sealing ring, the valve sleeve 18 is sequentially provided with five through holes along the axial direction, the valve sleeve 18 is respectively provided with a first oil return hole 33, a working oil hole A34, a high-pressure oil hole P35, a working oil hole B36 and a second oil return hole 37 from top to bottom, the inner cylindrical surface of the installation cylindrical cavity of the valve body 19 is provided with five annular grooves, and the five annular grooves are; the valve port T46 of the valve body 19 is communicated with the first oil return port 33 and the second oil return port 37 through the internal channel and the annular groove of the valve body 19, the valve port P48 of the valve body 19 is communicated with the high-pressure oil port P35 through the internal channel and the annular groove of the valve body 19, the valve port A47 of the valve body 19 is communicated with the working oil port A34 through the internal channel and the annular groove of the valve body 19, and the valve port B49 of the valve body 19 is communicated with the working oil port B36 through the internal channel and the annular groove of the valve body 19; the spring seat 16 is coaxially installed on the upper end surface of the valve sleeve 18 and axially limited and fixed by the upper end cover 22, the spring seat 16 is fixed relative to the valve sleeve 18, the spring seat 16 is used for supporting the first blocking cover 21, the second blocking cover 24 and the spring 23 of the valve core assembly 3, and the spring seat 16 is respectively in sealing contact connection with the valve body 19 and the upper end cover 22 through sealing rings.

The valve core assembly 3 comprises a valve core 17, a spring 23, a first stop cover 21 and a second stop cover 24, the valve core 17 is movably sleeved in the valve sleeve 18, a gap is formed between the valve core 17 and the valve sleeve 18, so that the valve core 17 axially moves and rotates relative to the valve sleeve 18, the top end of the valve core 17 sequentially penetrates through the valve sleeve 18 and the spring seat 16 upwards, the back of the upper end cover 22 is connected with the eccentric pin shaft 10 of the piezoelectric driving component 1, the valve core 17 is in clearance fit with the valve sleeve 18 and the inner hole of the spring seat 16, a first blocking cover 21, a second blocking cover 24 and a spring 23 are sleeved outside a shaft section extending between the spring seat 16 and the upper end cover 22 at the top end of the valve core 17, two ends of the spring 23 are respectively connected with the first blocking cover 21 and the second blocking cover 24, the first blocking cover 21 and the second blocking cover 24 are respectively installed at two ends of the spring 23, in the specific implementation, the first blocking cover 21 is positioned at the lower side of the spring 23 and connected to the spring seat 16, and the second blocking cover 24 is positioned at the upper side of the; a spring chamber 44 is formed inside the upper end cover 22 between the first blocking cover 21 and the second blocking cover 24, and the spring chamber 44 is communicated with the valve port P48 through the passage inside the upper end cover 22 and the valve body 19;

as shown in fig. 5, the piezoelectric driving assembly 1 includes an eccentric pin shaft 10 and two piezoelectric rotation driving sets, the eccentric pin shaft 10 is sleeved on the top end of the valve core 17, the top end of the valve core 17 is a square shaft, the eccentric pin shaft 10 is provided with an eccentric square hole, the square shaft of the valve core 17 is sleeved in the square hole, so that the eccentric pin shaft 10 is sleeved on the valve core 17 as a similar cam structure, and the two piezoelectric rotation driving sets have the same structure and are symmetrically arranged on two sides of the eccentric pin shaft 10; the group of piezoelectric rotation driving groups comprises a first support frame 7, a first piezoelectric actuator 8, a first shaft sleeve 9, a first fisheye joint 6 and a first pin shaft 5, wherein the inner end, close to the eccentric pin shaft 10, of the first support frame 7 is fixed on an upper end cover 22, the first pin shaft 5 is installed at the edge of the outer end, far away from the eccentric pin shaft 10, of the first support frame 7, the first pin shaft 5 is parallel to the valve core 17, the inner end of the first piezoelectric actuator 8 is hinged with the eccentric pin shaft 10 through the first shaft sleeve 9, the outer end of the first piezoelectric actuator 8 is hinged with the first pin shaft 5 through the first fisheye joint 6, and the first piezoelectric actuator 8 extends to push the eccentric pin shaft 10 to rotate around the square shaft center of the valve core 17 so as to drive the; the other group of piezoelectric rotation driving groups comprises a second support frame 12, a second piezoelectric actuator 13, a second shaft sleeve 11, a second fisheye joint 14 and a second pin shaft 15; the inner end of the second support frame 12 close to the eccentric pin shaft 10 is fixed on the upper end cover 22, the second pin shaft 15 is installed at the edge of the outer end of the second support frame 12 far away from the eccentric pin shaft 10, the second pin shaft 15 is parallel to the valve core 17, the inner end of the second piezoelectric actuator 13 is hinged with the eccentric pin shaft 10 through the second shaft sleeve 11, the outer end of the second piezoelectric actuator 13 is hinged with the second pin shaft 15 through the second fisheye joint 14, and the second piezoelectric actuator 13 extends to push the eccentric pin shaft 10 to rotate around the square shaft center of the valve core 17 so as to drive the valve core 17 to rotate around the second direction.

The inner end of the first piezoelectric actuator 8 is fixedly connected with one end of the first shaft sleeve 9 through a threaded hole and a threaded shaft, the other end of the first shaft sleeve 9 is sleeved outside the eccentric pin shaft 10, and the other end of the first shaft sleeve 9 is connected with the arc surface of the eccentric pin shaft 10 to form hinge joint; the outer end of the first piezoelectric actuator 8 is fixedly connected with one end of the first fisheye joint 6 through a threaded hole and a threaded shaft, the other end of the first fisheye joint 6 is sleeved on the first pin shaft 5, and the other end of the first fisheye joint 6 is connected with the first pin shaft 5 through the arc surface to form hinge joint.

The inner end of the second piezoelectric actuator 13 is fixedly connected with one end of the second shaft sleeve 11 through a threaded hole and a threaded shaft, the other end of the second shaft sleeve 11 is sleeved outside the eccentric pin shaft 10, and the other end of the second shaft sleeve 11 is connected with the eccentric pin shaft 10 through an arc surface to form hinge joint; the outer end of the second piezoelectric actuator 13 is fixedly connected with one end of a second fisheye joint 14 through a threaded hole and a threaded shaft, the other end of the second fisheye joint 14 is sleeved on a second pin shaft 15, and the other end of the second fisheye joint 14 is connected with the second pin shaft 15 through an arc surface to form hinge joint.

The center of a square hole of the eccentric pin shaft 10 is away from the central axis of the outer cylindrical surface by an eccentricity e, so that the first piezoelectric actuator 8, the first shaft sleeve 9, the eccentric pin shaft 10, the valve core 17, the valve sleeve 18, the first fisheye joint 6, the first pin shaft 5 and the first support frame 7 form a crank link mechanism, and the first piezoelectric actuator 8 extends to push the eccentric pin shaft 10 to rotate around the center of the square shaft of the valve core 17 so as to drive the valve core 17 to rotate around a first direction; the second piezoelectric actuator 13, the second shaft sleeve 11, the eccentric pin shaft 10, the valve core 17, the valve sleeve 18, the second fisheye joint 14, the second pin shaft 15 and the second support frame 12 form a crank link mechanism, and the second piezoelectric actuator 13 extends to push the eccentric pin shaft 10 to rotate around the square shaft center of the valve core 17 so as to drive the valve core 17 to rotate around the second direction.

The motion diagram of the crank-link mechanism is shown in fig. 9, and the degree of freedom is F-3 n-2P_L+P _H3 × 5-2 × 7 ═ 1, where F is the number of degrees of freedom of the mechanism, n is the book of the movable members of the mechanism, P_LFor a low number of pairs of mechanisms, P_HIs a high number of pairs of mechanisms.

Both the first piezoelectric actuator 8 and the second piezoelectric actuator 13 operate using piezoelectric ceramics.

The first direction and the second direction are both clockwise or counterclockwise, but the first direction and the second direction are opposite.

The positions of the first shaft sleeve 9 and the second shaft sleeve 11 in the two piezoelectric rotary driving groups, which are sleeved on the eccentric pin shaft 10, are staggered with each other, so that the rotation of the first shaft sleeve 9 relative to the eccentric pin shaft 10 and the rotation of the second shaft sleeve 11 relative to the eccentric pin shaft 10 do not interfere with each other. In a specific implementation, a groove may be formed in the middle of the first sleeve 9, and the second sleeve 11 is located in the groove.

As shown in fig. 6, the outer wall of the bottom of the valve core 17 is provided with a first spiral groove 25 and a second spiral groove 26, both the first spiral groove 25 and the second spiral groove 26 are grooves which do not penetrate through the side wall, and the bottom end surface of the valve core 17 is provided with a first oil passage 27 and a second oil passage 28 which are axially arranged; the first spiral groove 25 is communicated with a first oil channel 27 through a channel in the valve core 17, and the second spiral groove 26 is communicated with a second oil channel 28 through a channel in the valve core 17; one end of the first oil passage 27 at the bottom end of the valve core 17 is sealed by a plug, and the other end of the first oil passage 27 is communicated with the annular groove closest to the bottom end of the three annular grooves of the valve core 17, and in specific implementation, two first oil passages 27 may be provided, as shown in fig. 6 (c); one end of the second oil duct 28, which is positioned at the bottom end of the valve core 17, is closed by a plug, and the second oil duct 28 is communicated with the middle annular groove of the three annular grooves of the valve core 17; three annular grooves are formed in the middle of the valve core 17, an outer flange is formed between every two adjacent annular grooves, two outer flanges are formed between the three annular grooves, a first step 29 and a second step 30 which are matched with oil ports on the valve sleeve 18 are formed on the outer peripheral surfaces of the two outer flanges, and the periodic interval between the first step 29 and the second step 30 is the same as the periodic interval between every two adjacent oil ports of the valve sleeve 18;

as shown in fig. 7, a third spiral groove 32 is formed in the side wall of the bottom of the valve sleeve 18, the third spiral groove 32 is a through groove penetrating through the side wall, the third spiral groove 32 is communicated with the bottom sensitive cavity 45, a radial oil hole 31 is formed in the edge of the side wall of the valve sleeve 18 near the bottom end, and the radial oil hole 31 is a through hole penetrating through the side wall; the cylindrical cavity between the bottom end of the valve core 17 and the lower end cap 20 is used as a sensitive cavity 45.

The first helical groove 25 and the second helical groove 26 are alternately arranged to form a double helix structure. The rotation directions, the screw pitches and the groove widths of the first spiral groove 25, the second spiral groove 26 and the third spiral groove 32 are the same, the periodic interval between the first spiral groove 25 and the second spiral groove 26 is half of the screw pitch of the third spiral groove 32, and the adjacent interval between the first spiral groove 25 and the second spiral groove 26 is the same as the groove width of the third spiral groove 32; in any case, only one of the first helical groove 25 and the second helical groove 26 communicates with the third helical groove 32, i.e. the first helical groove 25 and the second helical groove 26 do not communicate with the third helical groove 32 at the same time.

A main valve port PA39 is formed between the upper side edge of the first step 29 of the valve core 17 and the working oil port A34, a main valve port AT42 is formed between the lower side edge of the first step 29 of the valve core 17 and the working oil port A34, a main valve port PB43 is formed between the lower side edge of the second step 30 of the valve core 17 and the working oil port B36, and a main valve port BT40 is formed between the upper side edge of the second step 30 of the valve core 17 and the working oil port B36; the main valve port PA39, the main valve port PB43, the main valve port AT42 and the main valve port BT40 between the valve core 17 and the valve sleeve 18 are opened and controlled in size by the hydraulic pressure of the high-pressure oil in the spring cavity 44 and the pressure oil in the sensitive cavity 45 and the spring force, as shown in FIG. 8.

In the initial state of closing the piezoelectric driving type rotary valve, the first step 29 and the second step 30 are respectively located at the working oil port A34 and the working oil port B36 and are blocked, the positions of the first spiral groove 25 and the second spiral groove 26 are not radially overlapped with the position of the third spiral groove 32, namely, the first spiral groove 25 and the second spiral groove 26 are not communicated with the third spiral groove 32.

When in work, the valve core is respectively communicated with the first spiral groove 25 and the third spiral groove 32 of the valve core 17 to form a control valve port CT41, the second spiral groove 26 is communicated with the third spiral groove 32 to form a control valve port PC38, a hydraulic control bridge circuit (as shown in figure 10) is formed, the pressure of the sensitive cavity 45 at the large end of the valve core 17 is controlled, and the relative displacement between the valve core 17 and the valve sleeve 18 is further adjusted.

The second oil passage 28 introduces high-pressure oil into the second spiral groove 26, and the high-pressure oil flows into the sensitive cavity 45 at the large end of the valve core 17 through the third spiral groove 32 of the valve sleeve 18; the first oil passage 27 communicates with the third spiral groove 32 of the valve sleeve 18 through the first spiral groove 25, and communicates the sensing chamber 45 of the large end of the valve spool 17 with the first oil return port 33.

In a specific implementation, the rotation direction of the first direction and the rotation direction of the first spiral groove (25) can be the same or opposite, and the rotation direction of the second direction and the rotation direction of the first spiral groove (25) can be opposite or the same.

The utility model discloses the specific implementation working process is:

1. closed valve state

When neither the first piezoelectric actuator 8 nor the second piezoelectric actuator 13 is energized or the polarity and magnitude of the applied voltage are the same, the state is in the initial state. The piezoelectric driving assembly 1, the valve core assembly 3 and the valve sleeve assembly 4 are all in zero positions.

For the piezoelectric drive assembly 1, the crank-link mechanism composed of the first piezoelectric actuator 8, the second piezoelectric actuator 13, the eccentric pin shaft 10, the valve core 17, the valve sleeve 18, and the like is in a middle zero position state, and the rotation angle θ of the valve core 17 at this time is set to be 0.

Neither the first helical groove 25 nor the second helical groove 26 communicates with the third helical groove 32, and the high-pressure oil flowing into the valve port P48 of the valve body 19 is not communicated with the sensitive chamber 45.

For the valve core assembly 3 and the valve sleeve assembly 4, the valve core 17 is in a balanced state under the hydraulic pressure of high-pressure oil in the spring cavity 44 and pressure oil in the large-end sensitive cavity 45 and the action of the spring force, and the main valve port PA39, the main valve port PB43, the main valve port AT42 and the main valve port BT40 between the valve core 17 and the valve sleeve 18 are in a closed state, as shown in fig. 8 a.

2. PA open state and BT open state

When the applied voltage of the first piezoelectric actuator 8 increases in the positive direction and the applied voltage of the second piezoelectric actuator 13 decreases in the negative direction, that is, the first piezoelectric actuator 8 extends and the second piezoelectric actuator 13 shortens, the crank-link mechanism composed of the first piezoelectric actuator 8, the second piezoelectric actuator 13, the eccentric pin shaft 10, the valve core 17, the valve sleeve 18 and the like rotates the drive valve core 17 in the first direction, and at this time, the valve core 17 is located at a rotation angle theta > 0, the rotation angle theta is small, and the rotation angle theta is proportional to the difference between the applied voltages of the first piezoelectric actuator 8 and the second piezoelectric actuator 13.

Due to the rotation angle θ, the spool 17 is driven to rotate in the first direction, so that the first spiral groove 25 and the third spiral groove 32 are communicated. For the valve core assembly 3 and the valve sleeve assembly 4, the second spiral groove 26 on the valve core 17 is not communicated with and closed by the control valve port PC38 formed by the third spiral groove 32 on the valve sleeve 18, and the first spiral groove 25 on the valve core 17 is communicated with and opened by the control valve port CT41 formed by the third spiral groove 32 on the valve sleeve 18. And the larger the rotation angle theta, the larger the control valve port CT 41.

The high-pressure oil flows in from the valve port P48 of the valve body 19 and enters the high-pressure oil port P35 of the valve sleeve 18, the high-pressure oil port P35 enters the second spiral groove 26 through the second oil passage 28, and the high-pressure oil does not enter the sensitive cavity 45 because the second spiral groove 26 is not communicated with the third spiral groove 32. Since the spring chamber 44 is always supplied with high-pressure oil, the valve element 17 is driven to move axially toward the sensitive chamber 45.

Under the action of the hydraulic control bridge circuit, the pressure oil in the sensing cavity 45 enters the first spiral groove 25 through the third spiral groove 32, enters the first oil passage 27 from the first spiral groove 25, enters the annular groove closest to the bottom end of the valve core 17 from the first oil passage 27, flows from the first oil return port to the oil return port T46, and finally returns from the valve port T46 and flows out. The pressure of the sensing cavity 45 at the large end of the valve core 17 is small, the pressure of the spring cavity 44 is large, the valve core 17 is pushed to move towards the sensing cavity 45 along the axial direction relative to the valve sleeve 18, and the control valve port CT41 is continuously reduced in the meantime until the hydraulic pressure and the spring force of the high-pressure oil in the spring cavity 44 and the pressure oil in the sensing cavity 45 are balanced, so that the valve core 17 is static relative to the valve sleeve 18.

AT this time, because the valve core 17 has been displaced relative to the valve housing 18 along the axial direction, the main valve port PB43 and the main valve port AT42 between the valve core 17 and the valve housing 18 are in the closed state, and the main valve port PA39 and the main valve port BT40 are in the open state, so that the working port a34 and the high-pressure port P35 are communicated, and the working port B36 and the second oil return port 37 are communicated, that is, the working state of "the valve port a47 and the valve port P48 are communicated, and the valve port B49 and the valve port T46 are communicated" is presented. And the opening amount is proportional to the rotation angle theta, so that the flow direction and the flow amount of the main oil passage hydraulic oil are controlled, as shown in fig. 8(c1) and fig. 8(c 2).

3. PB communication and AT communication state

When the applied voltage of the first piezoelectric actuator 8 is decreased in the negative direction and the applied voltage of the second piezoelectric actuator 13 is increased in the positive direction, that is, the first piezoelectric actuator 8 is shortened and the second piezoelectric actuator 13 is lengthened, the crank-link mechanism composed of the first piezoelectric actuator 8, the second piezoelectric actuator 13, the eccentric pin shaft 10, the valve core 17, the valve sleeve 18 and the like rotates the drive valve core 17 in the second direction, and at this time, the valve core 17 is located at a rotation angle theta > 0, the rotation angle theta is small, and the rotation angle theta is proportional to the difference between the applied voltages of the second piezoelectric actuator 13 and the first piezoelectric actuator 8.

Due to the rotation angle theta, the valve core 17 is driven to rotate around the second direction, so that the second spiral groove 26 and the third spiral groove 32 are communicated. For the valve core assembly 3 and the valve sleeve assembly 4, the second spiral groove 26 on the valve core 17 is communicated with and opened from the control valve port PC38 formed by the third spiral groove 32 on the valve sleeve 18, and the first spiral groove 25 on the valve core 17 is not communicated with and closed from the control valve port CT41 formed by the third spiral groove 32 on the valve sleeve 18. And the larger the angle of rotation theta, the larger the control valve port PC 38.

The high-pressure oil flows in from the valve port P48 of the valve body 19 and enters the high-pressure oil port P35 of the valve sleeve 18, the high-pressure oil port P35 enters the second spiral groove 26 through the second oil passage 28, and the high-pressure oil enters the sensitive cavity 45 because the second spiral groove 26 is communicated with the third spiral groove 32. Although the spring chamber 44 is constantly supplied with high-pressure oil, the active area of the sensitive chamber 45 is larger than the active area of the spring chamber 44, so that the valve slide 17 is moved axially toward the spring chamber 44.

Under the action of the hydraulic control bridge circuit, the pressure oil in the sensing cavity 45 sequentially enters the second spiral groove 26 through the third spiral groove 32, enters the second oil passage 28 through the second spiral groove 26, and is communicated to the high-pressure oil at the valve port P48 through the second oil passage 28.

The annular recess of the spool 17 nearest the bottom end does not communicate with the sensing chamber 45. Because the action area of the sensitive cavity 45 is larger than that of the spring cavity 44, the hydraulic pressure of the sensitive cavity 45 at the large end of the valve core 17 is large, the hydraulic pressure of the spring cavity 44 is small, the valve core 17 is pushed to move relatively to the valve sleeve 18 along the axial direction of the spring cavity 44, and the control valve port PC38 is continuously reduced at the same time until the hydraulic pressure and the spring force of the high-pressure oil in the spring cavity 44 and the pressure oil in the sensitive cavity 45 are balanced to make the valve core 17 static relative to the valve sleeve 18.

AT this time, because the valve core 17 has been displaced along the axial direction relative to the valve housing 18, the main valve port PB43 and the main valve port AT42 between the valve core 17 and the valve housing 18 are in the open state, and the main valve port PA39 and the main valve port BT40 are in the closed state, so that the first oil return port 33 and the working port a34 are communicated, the high-pressure port P35 and the working port B36 are communicated, and the second oil return port 37 is not communicated, that is, the working state of "the valve port B49 is communicated with the valve port P48, and the valve port a47 is communicated with the valve port T46" is presented. And the opening amount is proportional to the rotation angle theta, so that the flow direction and the flow amount of the main oil passage hydraulic oil are controlled, as shown in fig. 8(b1) and fig. 8(b 2).

In the working process of the piezoelectric driving type rotary valve, the piezoelectric driving device has the characteristics of large output force, high control precision, quick response and the like, and can effectively resist the influence of interference factors such as hydraulic force, friction force, clamping force and the like on the control precision and stability of the valve core, so that the through-flow capacity and the reliability of the hydraulic control valve, particularly the single-stage valve, can be greatly improved.

From this implementation process is visible, the utility model provides high change dynamic and static performance of valve has that operating pressure is high, the through-flow capacity is big, control accuracy is high, the response is fast, the anti-pollution ability is strong and advantages such as high reliability, can greatly widen the range of application of single-stage valve and change valve, and the wide application is in fields such as car, ocean boats and ships, aerospace and metallurgy, improves the intelligent and reliability level that high-pressure large-traffic hydraulic system especially proportional servo system's control characteristic and modern intelligence were equipped.

It should be noted that the foregoing is only a preferred embodiment of the present invention and the technical principles applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Any reference sign in a claim should not be construed as limiting the claim concerned. Therefore, although the present invention has been described in greater detail with reference to the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the scope of the present invention.

Claims (10)

1. A piezo-electrically driven rotary valve characterized by: the valve sleeve component (4) is arranged in a cylindrical hole in the center of the valve body component (2), the valve core component (3) is arranged in the cylindrical hole of the valve sleeve component (4) in a nested mode, and the piezoelectric driving component (1) is arranged on the upper end face of the valve sleeve component (4) and connected with the upper end of the valve core component (3) in a nested mode.

2. A piezo-actuated rotary valve according to claim 1, wherein: the valve body assembly (2) comprises a valve body (19), a lower end cover (20) and an upper end cover (22), wherein the valve body (19) is hollow to form a mounting cylindrical cavity, the lower end cover (20) is mounted on the lower end face of the valve body (19), and the upper end cover (22) is mounted on the upper end face of the valve body (19); the outer wall of the valve body (19) is provided with four valve holes which are respectively used as a valve port A (47), a valve port P (48), a valve port B (49) and a valve port T (46);

the valve sleeve component (4) comprises a valve sleeve (18) and a spring seat (16), the valve sleeve (18) is fixedly sleeved in an installation cylindrical cavity of the valve body (19), the valve sleeve (18) is sequentially provided with five through holes along the axial direction, a first oil return port (33), a working oil port A (34), a high-pressure oil port P (35), a working oil port B (36) and a second oil return port (37) are respectively arranged from top to bottom, a valve port T (46) of the valve body (19) is communicated with the first oil return port (33) and the second oil return port (37) through an internal channel of the valve body (19), a valve port P (48) of the valve body (19) is communicated with the high-pressure oil port P (35) through an internal channel of the valve body (19), a valve port A (47) of the valve body (19) is communicated with the working oil port A (34) through an internal channel of the valve body (19), and a valve port B (49) of the valve body (19) is communicated with the working oil port B (36) through; the spring seat (16) is coaxially arranged on the upper end surface of the valve sleeve (18) and is axially limited and fixed by the upper end cover (22), and the spring seat (16) is used for supporting a first blocking cover (21), a second blocking cover (24) and a spring (23) of the valve core assembly (3);

the valve core assembly (3) comprises a valve core (17), a spring (23), a first blocking cover (21) and a second blocking cover (24), the valve core (17) is movably sleeved on the valve sleeve (18), the top end of the valve core (17) sequentially penetrates through the valve sleeve (18), the spring seat (16) and the upper end cover (22) upwards and then is connected with the piezoelectric driving assembly (1), the first blocking cover (21), the second blocking cover (24) and the spring (23) are sleeved outside a shaft section, extending out between the spring seat (16) and the upper end cover (22), of the top end of the valve core (17), and two ends of the spring (23) are respectively connected with the first blocking cover (21) and the second blocking cover (24); a spring cavity (44) is formed inside the upper end cover (22) between the first blocking cover (21) and the second blocking cover (24), and the spring cavity (44) is communicated with the valve port P (48) through a channel inside the upper end cover (22) and the valve body (19);

the piezoelectric driving assembly (1) comprises an eccentric pin shaft (10) and two groups of piezoelectric rotary driving assemblies, wherein the eccentric pin shaft (10) is sleeved at the top end of a valve core (17), the top end of the valve core (17) is a square shaft, the eccentric pin shaft (10) is provided with an eccentric square hole, the square shaft of the valve core (17) is sleeved in the square hole, and the two groups of piezoelectric rotary driving assemblies are identical in structure and symmetrically arranged on two sides of the eccentric pin shaft (10); the group of piezoelectric rotary driving groups comprises a first support frame (7), a first piezoelectric actuator (8), a first shaft sleeve (9), a first fisheye joint (6) and a first pin shaft (5), wherein the inner end, close to the eccentric pin shaft (10), of the first support frame (7) is fixed on an upper end cover (22), the first pin shaft (5) is installed at the edge of the outer end, far away from the eccentric pin shaft (10), of the first support frame (7), the inner end of the first piezoelectric actuator (8) is hinged with the eccentric pin shaft (10) through the first shaft sleeve (9), and the outer end of the first piezoelectric actuator (8) is hinged with the first pin shaft (5) through the first fisheye joint (6); the other group of piezoelectric rotation driving groups comprises a second support frame (12), a second piezoelectric actuator (13), a second shaft sleeve (11), a second fisheye joint (14) and a second pin shaft (15); the inner end of the second support frame (12) close to the eccentric pin shaft (10) is fixed on the upper end cover (22), the second pin shaft (15) is installed at the edge of the outer end of the second support frame (12) far away from the eccentric pin shaft (10), the inner end of the second piezoelectric actuator (13) is hinged with the eccentric pin shaft (10) through the second shaft sleeve (11), and the outer end of the second piezoelectric actuator (13) is hinged with the second pin shaft (15) through the second fisheye joint (14).

3. A piezo-actuated rotary valve according to claim 2, wherein: the inner end of the first piezoelectric actuator (8) is fixedly connected with one end of the first shaft sleeve (9) through a threaded hole and a threaded shaft, the other end of the first shaft sleeve (9) is sleeved outside the eccentric pin shaft (10), and the other end of the first shaft sleeve (9) is connected with the eccentric pin shaft (10) through an arc surface to form hinge joint; the outer end of the first piezoelectric actuator (8) is fixedly connected with one end of the first fisheye joint (6) through a threaded hole and a threaded shaft, the other end of the first fisheye joint (6) is sleeved on the first pin shaft (5), and the other end of the first fisheye joint (6) is connected with the first pin shaft (5) through the arc surface to form hinge joint.

4. A piezo-actuated rotary valve according to claim 2, wherein: the inner end of the second piezoelectric actuator (13) is fixedly connected with one end of the second shaft sleeve (11) through a threaded hole and a threaded shaft, the other end of the second shaft sleeve (11) is sleeved outside the eccentric pin shaft (10), and the other end of the second shaft sleeve (11) is connected with the arc surface of the eccentric pin shaft (10) to form hinge joint; the outer end of the second piezoelectric actuator (13) is fixedly connected with one end of a second fisheye joint (14) through a threaded hole and a threaded shaft, the other end of the second fisheye joint (14) is sleeved on a second pin shaft (15), and the other end of the second fisheye joint (14) is connected with the second pin shaft (15) through an arc surface to form hinge joint.

5. A piezo-actuated rotary valve according to claim 2, wherein: the center of a square hole of the eccentric pin shaft (10) is away from the central axis of the outer cylindrical surface by an eccentricity e, so that a first piezoelectric actuator (8), a first shaft sleeve (9), the eccentric pin shaft (10), a valve core (17), a valve sleeve (18), a first fisheye joint (6), a first pin shaft (5) and a first support frame (7) form a crank link mechanism, and the first piezoelectric actuator (8) extends to push the eccentric pin shaft (10) to rotate around the center of the square shaft of the valve core (17) so as to drive the valve core (17) to rotate around a first direction; the second piezoelectric actuator (13), the second shaft sleeve (11), the eccentric pin shaft (10), the valve core (17), the valve sleeve (18), the second fisheye joint (14), the second pin shaft (15) and the second support frame (12) form a crank link mechanism, and the second piezoelectric actuator (13) extends to push the eccentric pin shaft (10) to rotate around the center of the square shaft of the valve core (17) so as to drive the valve core (17) to rotate around the second direction.

6. A piezo-actuated rotary valve according to claim 5, wherein:

the first direction and the second direction are both clockwise or anticlockwise, but the first direction and the second direction are opposite.

7. A piezo-actuated rotary valve according to claim 2, wherein: the positions of the first shaft sleeve (9) and the second shaft sleeve (11) in the two piezoelectric rotary driving groups, which are sleeved on the eccentric pin shaft (10), are staggered with each other, so that the rotation of the first shaft sleeve (9) relative to the eccentric pin shaft (10) and the rotation of the second shaft sleeve (11) relative to the eccentric pin shaft (10) do not interfere.

8. A piezo-actuated rotary valve according to claim 1, wherein: the outer wall of the bottom of the valve core (17) is provided with a first spiral groove (25) and a second spiral groove (26), the first spiral groove (25) and the second spiral groove (26) are both grooves which are not communicated with the side wall, and the bottom end face of the valve core (17) is provided with a first oil duct (27) and a second oil duct (28) which are axially arranged; the first spiral groove (25) is communicated with the first oil duct (27) through a channel in the valve core (17), and the second spiral groove (26) is communicated with the second oil duct (28) through a channel in the valve core (17); one end of the first oil duct (27) at the bottom end of the valve core (17) is sealed by a plug, and the other end of the first oil duct (27) is communicated with the annular groove closest to the bottom end of the three annular grooves of the valve core (17); one end of the second oil duct (28) at the bottom end of the valve core (17) is sealed by a plug, and the second oil duct (28) is communicated with the middle annular groove in the three annular grooves of the valve core (17); three annular grooves are formed in the middle of the valve core (17), two outer flanges are formed between the three annular grooves, the outer peripheral surfaces of the two outer flanges respectively form a first step (29) and a second step (30) which are used for being matched with each oil port on the valve sleeve (18), and the periodic interval between the first step (29) and the second step (30) is the same as the periodic interval between every two adjacent oil ports of the valve sleeve (18);

the side wall of the bottom of the valve sleeve (18) is provided with a third spiral groove (32), the third spiral groove (32) is a through groove penetrating through the side wall, the third spiral groove (32) is communicated with the bottom sensitive cavity (45), the edge of the side wall of the valve sleeve (18) close to the bottom end is provided with a radial oil hole (31), and the radial oil hole (31) is a through hole penetrating through the side wall; and a cylindrical installation cavity between the bottom end of the valve core (17) and the lower end cover (20) is used as a sensitive cavity (45).

9. A piezo-actuated rotary valve according to claim 8, wherein: the rotating directions, the screw pitches and the groove widths of the first spiral groove (25), the second spiral groove (26) and the third spiral groove (32) are the same, and the periodic interval between the first spiral groove (25) and the second spiral groove (26) is half of the screw pitch of the third spiral groove (32); in any case, only one of the first helical groove (25) and the second helical groove (26) communicates with the third helical groove (32), i.e. the first helical groove (25) and the second helical groove (26) do not communicate with the third helical groove (32) at the same time.

10. A piezo-actuated rotary valve according to claim 8, wherein: a main valve port PA (39) is formed between the upper side edge of the first step (29) of the valve core (17) and the working oil port A (34), a main valve port AT (42) is formed between the lower side edge of the first step (29) of the valve core (17) and the working oil port A (34), a main valve port PB (43) is formed between the lower side edge of the second step (30) of the valve core (17) and the working oil port B (36), and a main valve port BT (40) is formed between the upper side edge of the second step (30) of the valve core (17) and the working oil port B (36); the valve moves along the axial direction under the action of the hydraulic pressure of high-pressure oil in a spring cavity (44), pressure oil in a sensitive cavity (45) and spring force, and the opening and size control of a main valve port PA (39), a main valve port PB (43), a main valve port AT (42) and a main valve port BT (40) between a valve core (17) and a valve sleeve (18) are realized.

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