CN203548397U - Pilot high-flow load control valve based on displacement-force feedback principle - Google Patents
Pilot high-flow load control valve based on displacement-force feedback principle Download PDFInfo
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- CN203548397U CN203548397U CN201320716257.8U CN201320716257U CN203548397U CN 203548397 U CN203548397 U CN 203548397U CN 201320716257 U CN201320716257 U CN 201320716257U CN 203548397 U CN203548397 U CN 203548397U
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Abstract
The utility model discloses a pilot high-flow load control valve based on the displacement-force feedback principle. The pilot high-flow load control valve based on the displacement-force feedback principle comprises a main valve body, a main valve sleeve, a main valve element, a feedback spring, a loading pressure compensation damper, a pilot valve element, a pilot valve sleeve, a control spring, a control piston, a pilot valve body and an end cap. An oil return cavity, a load cavity, a control sensitive cavity, a high-pressure cavity, an inner containing cavity of the pilot valve element, an oil discharge cavity and a channel enabling the load cavity to be communicated with the high-pressure cavity are formed in the load control valve. For a hydraulic system with a negative load, the load control valve can control the load distributing speed and effectively restrain the problem that the loading speed of a traditional load control valve fluctuates. A vibration damping tail arranged on the head portion of the main valve element counteracts the influence of flow force borne by the main valve element. The main valve element integrates the function of control over the load distribution speed and the load increase one-way valve function, so that the load control valve is compact in overall structure. The pilot valve element is matched with the pilot valve sleeve in design, so that the load control valve has the rapid-closing function.
Description
Technical field
The utility model relates to hydraulic control component, especially relates to a kind of guide's heavy traffic load control valve of applying displacement-force feedback principle.
Background technique
In the hydraulic system applications such as such as the machinery that hoists, hydraulic wireline winch and engineering machinery, can often there is the situation that load force direction is consistent with load movement direction, this kind of load is called as and surmounts load (negative load).Bear the hydraulic system that surmounts load, need to have special control valve to control from the flow of the hydraulic oil in load flow oil return source, when load flow is larger, this kind of control valve is commonly referred to as load control valve or equilibrium valve.
But, because induced pressure is higher, loading condition complexity, the metering characteristics of load control valve directly determine speed control characteristic and the speed stability of hydraulic system.Conventional load control valve has that pilot pressure is high, the shortcoming of poor stability conventionally, load control valve becomes the bottleneck that restriction existence surmounts the hydraulic system performance of load, especially in heavy traffic load control valve field, the performance of load control valve directly affects a whole set of hydraulic system and then affects overall performance.
In view of this, application new principle, new method, the novel load control valve that development is applicable to exist large flow to surmount the hydraulic system of load has important practical meaning in engineering.
Summary of the invention
In order to overcome in background technique the deficiency that has load control valve or equilibrium valve loading speed control weak effect in the hydraulic system that surmounts load, loading speed shake easily occurs, the purpose of this utility model is to provide a kind of guide's heavy traffic load control valve of applying displacement-force feedback principle, this valve not only has good speed control characteristic, and main valve plug stability margin is large, effectively suppress the shake of loading speed, be applicable to exist the hydraulic system that surmounts load.
The technical solution adopted in the utility model is:
The utility model comprises main valve body, main valve housing, main valve plug, feedback spring, load pressure compensation damping, guide's spool, guide's valve pocket, control spring, control piston and guide valve blocks and end cap.
Main valve housing is installed in the cylindrical hole of main valve body, between main valve housing bottom and main valve body opening, form oil back chamber, main valve plug small end is through main valve housing and be positioned at oil back chamber, the large end of main valve plug and main valve housing endoporus are for being slidably matched, one end of guide's valve pocket is installed in main valve body cylindrical hole, the other end of guide's valve pocket is installed in guide valve blocks cylindrical hole, the large end of guide's spool is placed in guide's valve pocket and forms and be slidably matched, load pressure compensation damping is installed in the hole near guide's spool of the large end of main valve plug one side, one end of feedback spring is placed in the bottom, hole of main valve plug, the other end of feedback spring is set on the large end shoulder of guide's spool, between guide valve blocks and main valve body, be bolted, control piston is placed in the cylindrical hole of guide valve blocks and with guide valve blocks and forms and be slidably matched, and the small end of control piston withstands on the small end through guide's spool of first guide pin bushing, one end of control spring withstands on the cylindrical hole bottom of guide valve blocks, and the other end of control spring withstands on control piston shoulder, and end cap is arranged on guide valve blocks by bolt, and pushes down the large end of control piston, control piston, guide valve blocks and end cap coordinate formation control chamber jointly, and the center of end cap is provided with control port X, and control port X is communicated with control chamber.
Main valve body is provided with return opening A and is communicated with oil back chamber, and main valve body is provided with load hydraulic fluid port B and is communicated with load cavity; Main valve body cylindrical hole middle part coordinates and forms load cavity with main valve plug large end outside and main valve housing, and oil back chamber can be communicated with load cavity by main valve plug middle part valve port; Guide's valve pocket central groove coordinates formation hyperbaric chamber with main valve body cylindrical hole; Formation control sensitive cavity between main valve plug cylindrical hole, main valve housing, guide's valve pocket and the large end of guide's spool, controlling sensitive cavity can be communicated with load cavity by the large end rectangle groove of main valve plug, controlling sensitive cavity can be communicated with hyperbaric chamber by the large end valve mouth of guide's spool, and controlling sensitive cavity can be communicated with pilot valve core inner cavity volume by load pressure compensation damping internal holes; Guide's spool cylindrical hole, load pressure compensation damping and guide's valve pocket coordinate formation pilot valve core inner cavity volume, and pilot valve core inner cavity volume can be communicated with draining chamber by guide's spool small end valve port; Guide valve blocks coordinates formation draining chamber with control piston, guide valve blocks radially drain tap L is communicated with draining chamber.
Described guide's spool, main valve plug and control piston are coaxial, and guide's spool small end and main valve plug small end are for arranging in opposite directions.
Described main valve plug small end end is the boss structure with fillet.
The beneficial effect the utlity model has is:
For existence, surmount in the hydraulic system of load, this load control valve can carry out to load lowering velocity the control of efficiently and accurately; Owing to having applied displacement-force feedback principle, this load control valve has higher stability margin, and stable loading speed control can be provided, and has effectively suppressed the loading speed jitter problem of conventional load control valve.At main valve plug head design vibration damping stern construction, thereby effectively offset the impact of the suffered hydraulic power of main valve plug, further improved the stability of main valve plug.The non-return valve function that the speed controlling function that load is transferred and load are risen is integrated on main valve plug and completes, and makes load control valve compact overall structure.The matching design of guide's spool and guide's valve pocket, when guide's spool is closed, hyperbaric chamber is directly linked up with controlling sensitive cavity, raises rapidly, thereby promote main valve plug quick closedown thereby make to control sensitive cavity pressure, makes load control valve have quick closedown function.
Accompanying drawing explanation
Fig. 1 is structural principle schematic diagram of the present utility model.
Fig. 2 is the sectional drawing of A-A in Fig. 1.
Fig. 3 is the structural drawing of main valve plug and vibration damping tail thereof in Fig. 1.
Fig. 4 is the partial enlarged view at B place in Fig. 1.
Phase diagram when Fig. 5 is unidirectional the opening of load rising load control valve.
Fig. 6 is the phase diagram of load decline load control valve guide while opening.
In figure: 1, main valve body, 2, main valve housing, 3, main valve plug, 4, feedback spring, 5, load pressure compensation damping, 6, guide's spool, 7, guide's valve pocket, 8, control spring, 9, control piston, 10, guide valve blocks, 11, end cap, 12, oil back chamber, 13, load cavity, 14, control sensitive cavity, 15, passage, 16, hyperbaric chamber, 17, pilot valve core inner cavity volume, 18, draining chamber, 19, control chamber, 20, vibration damping tail.
Embodiment
Below in conjunction with drawings and Examples, the utility model is described in further detail.
As shown in Figure 1, the utility model comprises main valve body 1, main valve housing 2, main valve plug 3, feedback spring 4, load pressure compensation damping 5, guide's spool 6, guide's valve pocket 7, control spring 8, control piston 9 and guide valve blocks 10 and end cap 11.
As shown in Figure 1, main valve housing 2 is installed in the cylindrical hole of main valve body 1, between main valve housing 2 bottoms and main valve body 1 hole, form oil back chamber 12, main valve plug 3 small ends are through main valve housing 2 and be positioned at oil back chamber 12, the large end of main valve plug 3 and main valve housing 2 endoporus are for being slidably matched, one end of guide's valve pocket 7 is installed in main valve body 1 cylindrical hole, the other end of guide's valve pocket 7 is installed in guide valve blocks 10 cylindrical holes, played the effect that connects guiding, the large end of guide's spool 6 is placed in the interior formation of guide's valve pocket 7 and is slidably matched, load pressure compensation damping 5 is installed in the hole near guide's spool 6 of the large end of main valve plug one side, one end of feedback spring 4 is placed in the bottom, hole of main valve plug 3, the other end of feedback spring 4 is set on the large end shoulder of guide's spool 6, feedback spring 4 has certain initial compression amount, between guide valve blocks 10 and main valve body 1, by four interior hexagonal cylindrical hook bolts, be connected, to guarantee that guide's valve pocket 7 and main valve housing 2 are pressed in main valve body 1 with main valve body 1 without relative movement, control piston 9 is placed in the cylindrical hole of guide valve blocks 10 and with guide valve blocks 10 and forms and be slidably matched, and the small end of control piston 9 withstands on the small end through guide's spool 6 of first guide pin bushing 7, one end of control spring 8 withstands on the cylindrical hole bottom of guide valve blocks 10, and the other end of control spring 8 withstands on control piston 9 shoulders, and control spring 8 has certain initial compression amount, end cap 11 is arranged on guide valve blocks 10 by four interior hexagonal cylindrical hook bolts, and pushes down the large end of control piston 9, the common formation control chamber 19 that coordinates of control piston 9, guide valve blocks 10 and end cap 11, end cap 11 center is provided with control port X, and control port X is communicated with control chamber 19.
Described guide's spool 6, main valve plug 3 and control piston 9 are coaxial, and guide's spool 6 small ends and main valve plug 3 small ends are for arranging in opposite directions.
Described main valve plug 3 small end ends are the boss structure with fillet, are called vibration damping tail.Thereby effectively offset the impact of the suffered hydraulic power of main valve plug, improved the stability of main valve plug.
Between main valve plug 3 and guide's spool 6, by feedback spring 4, connect, the aperture displacement of main valve plug 3 is fed back on guide's spool 6 with the form of spring force, increased the stability margin of main valve plug 3, obtained good speed control characteristic and effectively suppress loading speed shake.
Load pressure compensation damping 5 is housed on guide's spool 6, when having realized induced pressure and exceeding certain value, along with induced pressure increases, by the hydraulic fluid flow rate of load control valve, reduces the effect of the safety of proof load and hydraulic system.
The vibration damping tail 20 of main valve plug 3 heads designs, and the effectively hydraulic power of negative function on main valve plug 3 further increases the stability of main valve plug 3.
By on integrated non-return valve function and main valve plug 3, changed the load of conventional load control valve transfer throttling function with the non-return valve function of load rising by two unaided designs of spool.
The matching design of guide's spool 6 and guide's valve pocket 7, when guide's spool 6 is closed, hyperbaric chamber 16 is directly linked up with controlling sensitive cavity 14, thereby make to control sensitive cavity 14 pressure, raises rapidly, thereby promote main valve plug 3 quick closedowns, make load control valve there is quick closedown function.
As shown in Figure 1, guide's heavy traffic load control valve of the utility model application displacement-feedback principle mainly comprises main valve plug assembly, pilot valve core assembly, control piston assembly and valve component.Main valve plug assembly comprises main valve plug 3, main valve housing 2 and feedback spring 4, main valve plug is placed in main valve housing, and can in main valve housing, move vertically, feedback spring 4 one end withstand on the bottom of main valve plug endoporus, wherein main valve plug left end cavity volume 12 communicates with load control valve return opening A, main valve plug middle part ring-shaped chamber 13 communicates with load control valve load hydraulic fluid port B, and main valve plug right-hand member cavity volume is for controlling sensitive cavity 14; Pilot valve core assembly consists of guide's spool 6, guide's valve pocket 7, load pressure compensation damping 5 and feedback spring 4, guide's spool is placed in guide's valve pocket, and formerly in guide valve bushing, move vertically, load pressure compensation damping is installed on guide's spool afterbody by screw thread, feedback spring one end is enclosed within guide's spool afterbody ladder place, and withstand its convex shoulder, wherein load pressure compensation damping left end cavity volume is for controlling sensitive cavity 14, and load pressure compensation damping right-hand member cavity volume is pilot valve core inner cavity volume 17; Control piston assembly consists of control piston 9 and control spring 8, control piston is placed in guide valve blocks cylindrical hole and can moves vertically therein, guide valve blocks cylindrical hole bottom is withstood in control spring one end, the other end is enclosed within on control piston and withstands control piston, wherein control piston left end cavity volume 18 communicates with load control valve drain tap L, and control piston right-hand member cavity volume communicates with load control valve control port X; Valve component consists of main valve body 1, guide valve blocks 10 and end cap 11, and main valve body is connected by 4 interior hexagonal cylindrical hook bolts with guide valve blocks, and end cap is connected by 4 interior hexagonal cylindrical hook bolts with guide valve blocks.
Fig. 2 has shown the be communicated with situation of load control valve load hydraulic fluid port B with load cavity 13.
Fig. 3 has shown the design of main valve plug head vibration damping tail, as shown in Figure 3, vibration damping tail is the band fillet boss structure of main valve plug head, when hydraulic oil flows out from main valve plug middle part valve port, this vibration damping stern construction can effectively be offset the suffered hydraulic power of main valve plug, thereby has increased the stability of main valve plug.
Fig. 4 has shown hyperbaric chamber 16 and the situation that is communicated with of controlling sensitive cavity 14, when guide valve core 6 is moved to the left in the ban, hyperbaric chamber 16 is blocked with control being communicated with of sensitive cavity 14, when guide valve core 6 sets back in the ban, hyperbaric chamber 16 is communicated with again with control sensitive cavity 14, and now the pressure oil in hyperbaric chamber enters and controls sensitive cavity 14, and the pressure of controlling sensitive cavity 14 raises, thereby promote main valve plug 3 to moving away from the direction of guide's spool 6, and then load control valve is closed.
Figure 5 shows that when load is risen, the state of load control valve during as one-way valve opens, now hydraulic oil enters load control valve from A mouth, promoting main valve plug 3 compressed feedback springs 4 moves to guide's spool 6 directions, valve port is opened, and hydraulic oil enters load cavity 13 through valve port, and then flows out from B mouth, load control valve is during as one-way valve opens, and guide's spool 6, control piston 9 are motionless in original position.
Figure 6 shows that when load declines, state when load control valve guide opens, first, pilot control oil enters control chamber 19 from control port X, promoting control piston 9 compression control springs 8 moves to main valve plug 3 directions, under the promotion of control piston 9, guide's spool 6 also moves to main valve plug 3 directions, poppet port between guide's spool 6 and guide's valve pocket 7 is opened, link up pilot valve core inner cavity volume 17 and draining chamber 18, pilot valve core inner cavity volume 17 pressure decreaseds, owing to controlling sensitive cavity 14, be connected by load pressure compensation damping 5 with pilot valve core inner cavity volume 17, so control sensitive cavity 14 pressure decreaseds, main valve plug 3 stress balances are broken, main valve plug 3 moves to guide's spool 6 directions, primary valve is opened, the pressure oil of B mouth is by load cavity 13, primary valve enters oil back chamber 12, and then flow out from load control valve A mouth, the movement of main valve plug 3 increases feedback spring 4 decrements, spring force increases, the stressed of guide's spool 6 is broken again, guide's spool 6 is to moving away from main valve plug 3 directions, poppet port turns down, the pressure of pilot valve core inner cavity volume 17 and control sensitive cavity 14 raises, main valve plug 3 stop motions, until main valve plug 3 and guide's spool 6 all reach stress balance, thereby the displacement that has reached main valve plug 3 feeds back to the effect of guide's spool 6 with the form of spring force.
Claims (3)
1. guide's heavy traffic load control valve of applying displacement-force feedback principle, is characterized in that: comprise main valve body (1), main valve housing (2), main valve plug (3), feedback spring (4), load pressure compensation damping (5), guide's spool (6), guide's valve pocket (7), control spring (8), control piston (9) and guide valve blocks (10) and end cap (11), main valve housing (2) is installed in the cylindrical hole of main valve body (1), between main valve housing (2) bottom and main valve body (1) hole, form oil back chamber (12), main valve plug (3) small end is through main valve housing (2) and be positioned at oil back chamber (12), the large end of main valve plug (3) and main valve housing (2) endoporus are for being slidably matched, one end of guide's valve pocket (7) is installed in main valve body (1) cylindrical hole, the other end of guide's valve pocket (7) is installed in guide valve blocks (10) cylindrical hole, the large end of guide's spool (6) is placed in guide's valve pocket (7) and forms and be slidably matched, load pressure compensation damping (5) is installed in the hole near guide's spool (6) of the large end of main valve plug (3) one side, one end of feedback spring (4) is placed in the bottom, hole of main valve plug (3), the other end of feedback spring (4) is set on the large end shoulder of guide's spool (6), between guide valve blocks (10) and main valve body (1), be bolted, control piston (9) is placed in the cylindrical hole of guide valve blocks (10) and with guide valve blocks (10) and forms and be slidably matched, and the small end of control piston (9) withstands on the small end through guide's spool (6) of guide's valve pocket (7), one end of control spring (8) withstands on the cylindrical hole bottom of guide valve blocks (10), the other end of control spring (8) withstands on control piston (9) shoulder, it is upper that end cap (11) is arranged on guide valve blocks (10) by bolt, and push down the large end of control piston (9), control piston (9), guide valve blocks (10) and end cap (11) coordinate formation control chamber (19) jointly, and the center of end cap (11) is provided with control port X, and control port X is communicated with control chamber (19),
Main valve body (1) is provided with return opening A and is communicated with oil back chamber (12), and main valve body (1) is provided with load hydraulic fluid port B and is communicated with load cavity (13); Main valve body (1) cylindrical hole middle part coordinates and forms load cavity (13) with main valve plug (3) large end outside and main valve housing (2), and oil back chamber (12) can pass through main valve plug (3) middle part valve port and be communicated with load cavity (13); Guide's valve pocket (7) central groove coordinates formation hyperbaric chamber (16) with main valve body (1) cylindrical hole; Formation control sensitive cavity (14) between the large end of main valve plug (3) cylindrical hole, main valve housing (2), guide's valve pocket (7) and guide's spool (6), controlling sensitive cavity (14) holds greatly rectangle groove to be communicated with load cavity (13) by main valve plug (3), controlling sensitive cavity (14) can be communicated with hyperbaric chamber (16) by the valve port of the large end of guide's spool (6), and controlling sensitive cavity (14) can be communicated with pilot valve core inner cavity volume (17) by load pressure compensation damping (5) internal holes; Guide's spool (6) cylindrical hole, load pressure compensation damping (5) and guide's valve pocket (7) coordinate formation pilot valve core inner cavity volume (17), and pilot valve core inner cavity volume (17) can be communicated with draining chamber (18) by guide's spool (6) small end valve port; Guide valve blocks (10) coordinates formation draining chamber (18) with control piston (9), guide valve blocks (10) radially drain tap L is communicated with draining chamber (18).
2. a kind of guide's heavy traffic load control valve of applying displacement-force feedback principle according to claim 1, it is characterized in that: described guide's spool (6), main valve plug (3) and control piston (9) are coaxial, guide's spool (6) small end and main valve plug (3) small end are for arranging in opposite directions.
3. a kind of guide's heavy traffic load control valve of applying displacement-force feedback principle according to claim 1, is characterized in that: described main valve plug (3) small end end is the boss structure with fillet.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320716257.8U CN203548397U (en) | 2013-11-14 | 2013-11-14 | Pilot high-flow load control valve based on displacement-force feedback principle |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320716257.8U CN203548397U (en) | 2013-11-14 | 2013-11-14 | Pilot high-flow load control valve based on displacement-force feedback principle |
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| CN203548397U true CN203548397U (en) | 2014-04-16 |
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| CN201320716257.8U Expired - Fee Related CN203548397U (en) | 2013-11-14 | 2013-11-14 | Pilot high-flow load control valve based on displacement-force feedback principle |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103573735A (en) * | 2013-11-14 | 2014-02-12 | 浙江大学 | Pilot large-flow load control valve using displacement and force feedback principle |
| CN106015149A (en) * | 2016-08-08 | 2016-10-12 | 浙江大学 | Vibration-reduction tail structure for eliminating reverse hydraulic power of valve core of one-way slide valve |
| CN106050775A (en) * | 2016-06-11 | 2016-10-26 | 宁波文泽机电技术开发有限公司 | Pilot control valve of improved structure |
| CN112431806A (en) * | 2020-10-20 | 2021-03-02 | 浙江大学 | Pilot high-flow load control valve with back pressure compensation function |
-
2013
- 2013-11-14 CN CN201320716257.8U patent/CN203548397U/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103573735A (en) * | 2013-11-14 | 2014-02-12 | 浙江大学 | Pilot large-flow load control valve using displacement and force feedback principle |
| CN106050775A (en) * | 2016-06-11 | 2016-10-26 | 宁波文泽机电技术开发有限公司 | Pilot control valve of improved structure |
| CN106015149A (en) * | 2016-08-08 | 2016-10-12 | 浙江大学 | Vibration-reduction tail structure for eliminating reverse hydraulic power of valve core of one-way slide valve |
| CN106015149B (en) * | 2016-08-08 | 2017-09-29 | 浙江大学 | The vibration damping stern construction eliminated for the reverse hydraulic power of unilateral valve core of the spool valve |
| CN112431806A (en) * | 2020-10-20 | 2021-03-02 | 浙江大学 | Pilot high-flow load control valve with back pressure compensation function |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140416 Termination date: 20151114 |
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| EXPY | Termination of patent right or utility model |