CN111720381B - Balance valve, hydraulic control system and engineering machinery - Google Patents
Balance valve, hydraulic control system and engineering machinery Download PDFInfo
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- CN111720381B CN111720381B CN202010610795.3A CN202010610795A CN111720381B CN 111720381 B CN111720381 B CN 111720381B CN 202010610795 A CN202010610795 A CN 202010610795A CN 111720381 B CN111720381 B CN 111720381B
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- oil
- cavity
- balance valve
- balance
- valve core
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/021—Valves for interconnecting the fluid chambers of an actuator
Abstract
The invention relates to the technical field of hydraulic control, in particular to a balance valve, a hydraulic control system and engineering machinery, wherein the balance valve comprises a valve body, a direction valve core, a balance valve core and a balance valve spring, and the valve body is provided with a pressure oil port, a working oil port and an oil return port; the direction valve core is arranged in the valve body in a sliding mode, the direction valve core is provided with a cavity, and a first oil hole and a second oil hole which are communicated with the cavity are formed in the direction valve core; the balance valve core is arranged in the cavity in a sliding mode, the balance valve core divides the cavity into a first oil cavity and a second oil cavity, and a pressure oil duct which is communicated with the working oil port and the second oil cavity is arranged on the valve body; the balance valve spring is connected between the direction valve core and the balance valve core. The balance valve provided by the invention can realize the control of lifting and lowering of the hydraulic cylinder, and the direction valve core and the balance valve core are integrally arranged, so that the structure is simplified, the number of elements is reduced, the arrangement of oil passages among different elements is avoided, and the processing cost is further reduced.
Description
Technical Field
The invention relates to the technical field of hydraulic control, in particular to a balance valve, a hydraulic control system and engineering machinery.
Background
At present, the main actions of domestic engineering machinery comprise lifting and lowering, front and back inclination and the like so as to complete various actual working processes. Usually, the two very critical and important actions of lifting and lowering are mainly realized by using a hydraulic cylinder, and the two actions are generally controlled by a direction valve and a proportional valve which are arranged in a split manner, because all elements need to work in a mutual cooperation mode, flow-through channels for communicating different elements need to be designed in the design process of a valve body, the structural design of the valve body is relatively complex, and an oil passage is also relatively complex.
Disclosure of Invention
The invention aims to provide a balance valve, a hydraulic control system and engineering machinery, and aims to solve the technical problems that in the prior art, a hydraulic cylinder is controlled to lift, a lower valve body is complex in structure and an oil duct is complex.
In order to achieve the purpose, the invention adopts the following technical scheme:
a balanced valve comprising:
the hydraulic control valve comprises a valve body, a hydraulic pump, a hydraulic cylinder, a first pilot end cover, a second pilot end cover and control oil, wherein a pressure oil port communicated with the hydraulic pump, a working oil port communicated with a rodless cavity of the hydraulic cylinder and an oil return port communicated with an oil tank are formed in the valve body;
the direction valve core is arranged in the valve body in a sliding mode, the direction valve core is provided with a cavity, and a first oil hole and a second oil hole which are communicated with the cavity are formed in the direction valve core;
the balance valve core is arranged in the cavity in a sliding mode, the balance valve core divides the cavity into a first oil cavity close to the first oil hole and the second oil hole and a second oil cavity far away from the first oil hole and the second oil hole, and a pressure oil duct for communicating the working oil hole and the second oil cavity is arranged on the valve body;
and the balance valve spring is connected between the direction valve core and the balance valve core.
As a preferable technical solution of the balance valve, an end surface of one end of the balance valve core close to the first oil hole and the second oil hole is a conical surface.
As a preferable mode of the balance valve, the balance valve body includes a large diameter portion on a side close to the first oil hole and the second oil hole and a small diameter portion on a side far from the first oil hole and the second oil hole, and the balance valve spring is fitted to the small diameter portion.
As a preferable technical scheme of the balance valve, a thread is arranged on the small-diameter portion, a nut is in threaded connection with the small-diameter portion, one end of the balance valve spring is connected with the inner wall of the cavity, and the other end of the balance valve spring is connected with the nut.
As a preferred technical solution of the balance valve, a positioning element is provided on the small diameter portion, the positioning element includes a first flat portion parallel to an axis of the small diameter portion and a second flat portion perpendicular to the axis of the small diameter portion, the first flat portion is slidably connected to the small diameter portion, the second flat portion can abut against an inner wall of the cavity, and one end of the balance valve spring is connected to the second flat portion.
As a preferable technical solution of the balance valve, the cavity is a stepped hole, and includes a first hole having a smaller diameter and a second hole having a larger diameter, the large-diameter portion of the balance valve element is slidably disposed in the first hole, the small-diameter portion of the balance valve element is disposed in the second hole, and the second straight portion abuts against a connection surface between the first hole and the second hole.
As a preferable technical solution of the balance valve, a first spring connected to a first end of the direction spool is provided in the first pilot end cap.
As a preferable technical solution of the balance valve, a second spring connected to the second end of the direction spool is provided in the second pilot end cap.
A hydraulic control system comprising a balancing valve as described in any one of the preceding claims.
A construction machine comprises the hydraulic control system in the scheme.
The invention has the beneficial effects that:
the invention provides a balance valve which comprises a valve body, a direction valve core, a balance valve core and a balance valve spring. The valve body is provided with a pressure oil port communicated with the hydraulic pump, a working oil port communicated with a rodless cavity of the hydraulic cylinder and an oil return port communicated with the oil tank, openings on two sides of the valve body are respectively provided with a first pilot end cover and a second pilot end cover, and the first pilot end cover and the second pilot end cover are both communicated with control oil; the direction valve core is arranged in the valve body in a sliding mode, the direction valve core is provided with a cavity, and a first oil hole and a second oil hole which are communicated with the cavity are formed in the direction valve core; the balance valve core is arranged in the cavity in a sliding mode, the balance valve core divides the cavity into a first oil cavity close to the first oil hole and the second oil hole and a second oil cavity far away from the first oil hole and the second oil hole, and a pressure oil duct communicated with the working oil hole and the second oil cavity is arranged on the valve body; the balance valve spring is connected between the direction valve core and the balance valve core. The balance valve provided by the invention can realize the control of lifting and lowering of the hydraulic cylinder, and the direction valve core and the balance valve core are integrally arranged, so that the structure is simplified, the number of elements is reduced, the arrangement of oil passages among different elements is avoided, and the processing cost is further reduced; and the cavity is formed in the direction valve core, and the balance valve core is arranged in the cavity of the direction valve core, so that the whole structure is more compact.
Drawings
Fig. 1 is a schematic structural diagram of a balance valve provided in an embodiment of the present invention.
In the figure:
10. a valve body; 11. a pressure oil port; 12. a working oil port; 13. an oil return port; 14. a pressure channel; 20. a first pilot end cap; 30. a second pilot end cap; 40. a directional valve core; 41. a first oil chamber; 42. a second oil chamber; 43. a first oil hole; 44. a second oil hole; 50. a balanced valve core; 51. a large diameter portion; 52. a small diameter part; 60. a balance valve spring; 70. a first spring; 80. a second spring; 90. a positioning member; 91. a first straight portion; 92. a second straight portion; 100. and a nut.
Detailed Description
The technical scheme of the invention is further explained by combining the attached drawings and the embodiment. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some but not all of the features relevant to the present invention are shown in the drawings.
In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.
In the description of the present embodiment, the terms "upper", "lower", "left", "right", and the like are used based on the orientations and positional relationships shown in the drawings only for convenience of description and simplification of operation, and do not indicate or imply that the referred device or element must have a specific orientation, be configured and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.
As shown in fig. 1, the present invention provides a balance valve including a valve body 10, a direction valve spool 40, a balance valve spool 50, and a balance valve spring 60. A pressure oil port 11 communicated with a hydraulic pump, a working oil port 12 communicated with a rodless cavity of a hydraulic cylinder and an oil return port 13 communicated with an oil tank are formed in the valve body 10, a first pilot end cover 20 and a second pilot end cover 30 are respectively arranged at openings on two sides of the valve body 10, and the first pilot end cover 20 and the second pilot end cover 30 are both communicated with control oil; the direction valve core 40 is arranged in the valve body 10 in a sliding mode, the direction valve core 40 is provided with a cavity, and a first oil hole 43 and a second oil hole 44 which are communicated with the cavity are formed in the direction valve core 40; the balance valve core 50 is slidably arranged in the cavity, the balance valve core 50 divides the cavity into a first oil chamber 41 close to the first oil hole 43 and the second oil hole 44 and a second oil chamber 42 far away from the first oil hole 43 and the second oil hole 44, and a pressure oil passage for communicating the working oil port 12 and the second oil chamber 42 is arranged on the valve body 10; the balance valve spring 60 is connected between the direction valve spool 40 and the balance valve spool 50.
For convenience of description, the operation of the balance valve according to the present invention is as follows, and the pilot cap on the side far from the balance valve body 50 is defined as a first pilot cap 20, and the pilot cap on the side near the balance valve body 50 is defined as a second pilot cap 30. When the hydraulic cylinder needs to be lifted, control oil is introduced into the second pilot end cover 30, the direction control valve core 40 moves towards the direction close to the first pilot end cover 20, the first oil hole 43 is communicated with the pressure oil port 11 and the first oil chamber 41, and the second oil hole 44 is communicated with the first oil chamber 41 and the working oil port 12, so that the oil flows into a rodless cavity of the hydraulic cylinder, and the hydraulic cylinder is driven to realize the lifting action. When the hydraulic cylinder needs to be lowered, hydraulic oil is introduced into the first pilot end cover 20, the direction valve core 40 is controlled to move towards the direction close to the second pilot end cover 30, the first oil hole 43 is communicated with the working oil port 12 and the first oil chamber 41, the second oil hole 44 is communicated with the oil return port 13 and the first oil chamber 41, oil in the rodless chamber of the hydraulic cylinder can be returned through the oil return port 13, meanwhile, pressure oil in the rodless chamber of the hydraulic cylinder flows into the second oil chamber 42 through the pressure oil duct, when the load gravity of the hydraulic cylinder is small, the pressure oil in the second oil chamber 42 cannot overcome the elastic force of the balance valve spring 60, so that the balance valve core 50 cannot be pushed to move, at the moment, the balance valve core 50 does not work, when the load gravity of the hydraulic cylinder is large, the pressure oil in the second oil chamber 42 can overcome the elastic force of the balance valve spring 60, so that the balance valve core 50 can be pushed to move, and the second oil hole 44 can be slowly closed when the balance valve core 50 moves, that is, the balance valve body 50 can control the flow area of the second oil hole 44 to control the oil pressure in the first oil chamber 41, and when the pressures on both sides of the balance valve body 50 reach a balanced state, the balance valve body 50 stops moving, and at this time, the hydraulic cylinder can be smoothly lowered.
The balance valve provided by the invention can realize the control of lifting and lowering of the hydraulic cylinder, and the direction valve core 40 and the balance valve core 50 are integrated, so that the structure is simplified, the number of elements is reduced, the arrangement of oil passages among different elements is avoided, and the processing cost is further reduced; and the cavity is arranged on the direction valve core 40, and the balance valve core 50 is arranged in the cavity of the direction valve core 40, so that the whole structure is more compact.
Furthermore, the end surfaces of the balanced valve core 50 close to one ends of the first oil hole 43 and the second oil hole 44 are conical surfaces, so that when the balanced valve core 50 partially blocks the oil return opening 13, the oil in the first oil chamber 41 can flow to the oil return opening 13 along the conical surfaces, the flow resistance of the oil can be reduced, and the smoothness of the oil flow can be improved.
The balanced valve core 50 includes a large diameter portion 51 near the first and second oil holes 43 and 44 and a small diameter portion 52 far from the first and second oil holes 43 and 44, and a balanced valve spring 60 is sleeved on the small diameter portion 52 to facilitate the arrangement of the spring. Furthermore, a thread is arranged on the small diameter part 52, a nut is in threaded connection with the small diameter part 52, one end of the balance valve spring 60 is connected with the inner wall of the cavity, the other end of the balance valve spring 60 is connected with the nut 100, the elasticity of the balance valve spring 60 can be adjusted through the nut 100, and the application range of the balance valve is widened. Furthermore, the small diameter portion 52 is provided with a retainer 90, the retainer 90 includes a first straight portion 91 parallel to the axis of the small diameter portion 52 and a second straight portion 92 perpendicular to the axis of the small diameter portion 52, the first straight portion 91 is connected to the small diameter portion 52, the second straight portion 92 can abut against the inner wall of the cavity, and one end of the balanced valve spring 60 is connected to the second straight portion 92. Through such an arrangement, the connection of the balance valve spring 60 can be facilitated, and the processing of an excessively thick positioning surface on the inner wall of the direction valve core 40 can be avoided. In this embodiment, the cavity is a stepped hole, and includes a first hole with a smaller diameter and a second hole with a larger diameter, the large diameter portion 51 of the balance valve core 50 is slidably disposed in the first hole, the small diameter portion 52 of the balance valve core 50 is disposed in the second hole, and the second straight portion 92 abuts against a connection surface of the first hole and the second hole. Alternatively, a convex structure is directly provided on the inner wall of the cavity, and an end surface of the convex structure facing the small diameter portion 52 is a positioning surface for abutting against the second flat portion 92 of the positioning member 90.
A first spring 70 connected to a first end of the direction valve body 40 is provided in the first pilot end cap 20, and a second spring 80 connected to a second end of the direction valve body 40 is provided in the second pilot end cap 30 to damp movement of the direction valve body 40.
The invention also provides a hydraulic control system which comprises the balance valve in the scheme, so that the structure of the hydraulic control system and the arrangement of oil passages are simplified.
The invention further provides engineering machinery which comprises the hydraulic control system in the scheme, and the structure and the oil channel arrangement of the engineering machinery are simplified.
It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. This need not be, nor should it be exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.
Claims (10)
1. A balanced valve, comprising:
the hydraulic control valve comprises a valve body (10), a hydraulic pump, a hydraulic cylinder, a first pilot end cover (20) and a second pilot end cover (30), wherein a pressure oil port (11) communicated with the hydraulic pump, a working oil port (12) communicated with a rodless cavity of the hydraulic cylinder and an oil return port (13) communicated with an oil tank are formed in the valve body (10), openings on two sides of the valve body (10) are respectively provided with the first pilot end cover (20) and the second pilot end cover (30), and the first pilot end cover (20) and the second pilot end cover (30) are both communicated with control oil;
the direction valve core (40) is arranged in the valve body (10) in a sliding mode, the direction valve core (40) is provided with a cavity, and a first oil hole (43) and a second oil hole (44) which are communicated with the cavity are formed in the direction valve core (40);
the balance valve core (50) is arranged in the cavity in a sliding mode, the balance valve core (50) divides the cavity into a first oil cavity (41) close to the first oil hole (43) and the second oil hole (44) and a second oil cavity (42) far away from the first oil hole (43) and the second oil hole (44), and a pressure oil passage for communicating the working oil port (12) and the second oil cavity (42) is arranged on the valve body (10);
a balance valve spring (60) connected between the direction spool (40) and the balance spool (50);
when the hydraulic cylinder needs to be lifted, control oil is introduced into the second pilot end cover (30), the direction valve core (40) is controlled to move towards the direction close to the first pilot end cover (20), the first oil hole (43) is communicated with the pressure oil port (11) and the first oil cavity (41), and meanwhile the second oil hole (44) is communicated with the first oil cavity (41) and the working oil port (12), so that the oil flows into a rodless cavity of the hydraulic cylinder;
when the hydraulic cylinder needs to be lowered, hydraulic oil is introduced into the first pilot end cover (20), the direction valve core (40) is controlled to move towards the direction close to the second pilot end cover (30), the first oil hole (43) is communicated with the working oil port (12) and the first oil cavity (41), meanwhile, the second oil hole (44) is communicated with the oil return port (13) and the first oil cavity (41), oil in the rodless cavity of the hydraulic cylinder can return through the oil return port (13), and meanwhile pressure oil in the rodless cavity of the hydraulic cylinder flows into the second oil cavity (42) through the pressure oil channel.
2. The balance valve according to claim 1, wherein end surfaces of the balance valve body (50) at ends close to the first oil hole (43) and the second oil hole (44) are tapered surfaces.
3. The balance valve according to claim 1, wherein the balance valve spool (50) includes a large diameter portion (51) near the first and second oil holes (43, 44) side and a small diameter portion (52) far from the first and second oil holes (43, 44) side, and the balance valve spring (60) is fitted to the small diameter portion (52).
4. The balance valve according to claim 3, wherein a thread is provided on the small diameter portion (52), a nut (100) is threadedly coupled to the small diameter portion (52), one end of the balance valve spring (60) is coupled to an inner wall of the cavity, and the other end of the balance valve spring (60) is coupled to the nut (100).
5. The balance valve according to claim 4, wherein a positioning member (90) is provided on the small diameter portion (52), the positioning member (90) comprises a first straight portion (91) parallel to an axis of the small diameter portion (52) and a second straight portion (92) perpendicular to the axis of the small diameter portion (52), the first straight portion (91) is slidably connected with the small diameter portion (52), the second straight portion (92) can abut against an inner wall of the cavity, and one end of the balance valve spring (60) is connected with the second straight portion (92).
6. The balance valve of claim 5, wherein the cavity is a stepped bore comprising a first bore having a smaller diameter and a second bore having a larger diameter, the large diameter portion (51) of the balance spool (50) is slidably disposed in the first bore, the small diameter portion (52) of the balance spool (50) is disposed in the second bore, and the second flat portion (92) abuts against a connecting surface of the first bore and the second bore.
7. A balancing valve according to any of claims 1-6, characterized in that a first spring (70) is arranged in the first pilot end cap (20) in connection with the first end of the direction spool (40).
8. The balancing valve of claim 7, characterized in that a second spring (80) is provided in the second pilot end cap (30) in connection with the second end of the direction spool (40).
9. A hydraulic control system comprising a balancing valve according to any of claims 1-8.
10. A working machine, characterized by comprising a hydraulic control system according to claim 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010610795.3A CN111720381B (en) | 2020-06-29 | 2020-06-29 | Balance valve, hydraulic control system and engineering machinery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010610795.3A CN111720381B (en) | 2020-06-29 | 2020-06-29 | Balance valve, hydraulic control system and engineering machinery |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111720381A CN111720381A (en) | 2020-09-29 |
| CN111720381B true CN111720381B (en) | 2022-07-15 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010610795.3A Active CN111720381B (en) | 2020-06-29 | 2020-06-29 | Balance valve, hydraulic control system and engineering machinery |
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| CN (1) | CN111720381B (en) |
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| JPH1130351A (en) * | 1997-07-10 | 1999-02-02 | Ebara Corp | Hydraulic relief valve |
| CN201407244Y (en) * | 2009-05-18 | 2010-02-17 | 中国第一冶金建设有限责任公司 | Novel hydraulic control system with balance valve |
| CN204739299U (en) * | 2015-05-21 | 2015-11-04 | 佛山市高明安华陶瓷洁具有限公司 | Scald preventing constant temperature tap structure with balanced case |
| CN105952705A (en) * | 2016-06-29 | 2016-09-21 | 宁波文泽机电技术开发有限公司 | Balance valve |
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| DE3912779C2 (en) * | 1989-04-19 | 1997-09-11 | Linde Ag | Pressure relief valve |
| DE4335086C1 (en) * | 1993-10-14 | 1995-03-23 | Linde Ag | Valve with a safety device for releasing the valve spool |
| US5875811A (en) * | 1997-04-17 | 1999-03-02 | Dana Corporation | Counterbalance valve with improved relief pressure setting arrangement |
| JP2002357276A (en) * | 2001-06-01 | 2002-12-13 | Yuken Kogyo Co Ltd | Counter balance valve |
| CN203702216U (en) * | 2013-12-09 | 2014-07-09 | 四川航天电液控制有限公司 | Soft-start valve |
| CN203641148U (en) * | 2013-12-26 | 2014-06-11 | 中联重科股份有限公司 | Balance valve and hydraulic cylinder telescopic control loop |
| CN107725820B (en) * | 2017-10-18 | 2019-05-21 | 立信阀门集团有限公司 | No leakage Solenoid ball valve |
| CN207648178U (en) * | 2017-12-29 | 2018-07-24 | 湖南鸿辉科技有限公司 | A kind of balanced valve |
| CN210423209U (en) * | 2019-07-27 | 2020-04-28 | 蚌埠液力机械有限公司 | Integrated variable control valve |
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- 2020-06-29 CN CN202010610795.3A patent/CN111720381B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1130351A (en) * | 1997-07-10 | 1999-02-02 | Ebara Corp | Hydraulic relief valve |
| CN201407244Y (en) * | 2009-05-18 | 2010-02-17 | 中国第一冶金建设有限责任公司 | Novel hydraulic control system with balance valve |
| CN204739299U (en) * | 2015-05-21 | 2015-11-04 | 佛山市高明安华陶瓷洁具有限公司 | Scald preventing constant temperature tap structure with balanced case |
| CN105952705A (en) * | 2016-06-29 | 2016-09-21 | 宁波文泽机电技术开发有限公司 | Balance valve |
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| CN111720381A (en) | 2020-09-29 |
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