CN209212677U - A kind of combination counterbalance valve and back pressure apparatus - Google Patents
A kind of combination counterbalance valve and back pressure apparatus Download PDFInfo
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- CN209212677U CN209212677U CN201821842411.5U CN201821842411U CN209212677U CN 209212677 U CN209212677 U CN 209212677U CN 201821842411 U CN201821842411 U CN 201821842411U CN 209212677 U CN209212677 U CN 209212677U
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Abstract
The utility model discloses a kind of combination counterbalance valve and back pressure apparatus, are related to technical field of hydraulic pressure.Combining counterbalance valve includes valve body, which is provided with entrance and exit, and valve inner is equipped with the main oil gallery of connection entrance and exit;Valve inner, which is equipped with, passes through the pressure valve module of main oil gallery parallel connection, control valve group and direction valve module, wherein, by the first control oil communication between the oil inlet of control valve group and the control mouth of pressure valve module, and the first damping structure is equipped between the oil inlet and entrance of control valve group;The cracking pressure P of direction valve moduleaThe cracking pressure P of≤control valve groupc, work as P-P2≥PbWhen, pressure valve module is opened, wherein P is the oil pressure of entrance, P2For the control mouth pressure of pressure valve module, PbFor pressure threshold.The utility model is capable of the return oil pressure of stable hydraulic system, guarantees the stability of hydraulic system when the return flow of hydraulic system changes in a big way.
Description
Technical field
The utility model relates to the return oil pressure technical field in hydraulic system, be specifically related to a kind of combination counterbalance valve and
Back pressure apparatus.
Background technique
The executing agency that industrial hydraulic system usually has multiple groups parallel, different executing agencies are required in movement
Hydraulic fluid flow rate is usually different from, therefore the return flow of hydraulic system usually changes in a big way.In conventional hydraulic
In the use process of system, when the return flow of hydraulic system differs larger with the nominal operation flow for combining counterbalance valve, liquid
The back pressure of pressure system can be increased with the increase of return flow, can also be reduced with the reduction of return flow, so as to cause
Larger fluctuation occurs for the return oil pressure of hydraulic system, reduces the stability of hydraulic system, generates vibration and noise, or even damage liquid
Press element and equipment.
Utility model content
In view of the deficiencies in the prior art, the purpose of this utility model is to provide a kind of combination counterbalance valve and back pressures
Device is capable of the return oil pressure of stable hydraulic system when the return flow of hydraulic system changes in a big way, guarantees liquid
The stability of pressure system.
The utility model provides a kind of combination counterbalance valve comprising:
Valve body, which is provided with entrance and exit, and valve inner is equipped with the main oil gallery for being connected to the entrance and exit;
The valve inner is equipped with through the pressure valve module of main oil gallery parallel connection, control valve group and direction valve module,
In, oil communication, and control valve group are controlled by first between the oil inlet of control valve group and the control mouth of pressure valve module
The first damping structure is equipped between the oil inlet of part and the entrance;
The cracking pressure P of the direction valve moduleaThe cracking pressure P of≤control valve groupc, work as P-P2≥PbWhen, institute
State the unlatching of pressure valve module, wherein P is the oil pressure of the entrance, P2For the control mouth pressure of the pressure valve module, PbFor pressure
Force threshold.
Based on the above technical solution, the pressure valve module and direction valve module are inserted valve.
Based on the above technical solution, the valve body includes connected valve block and the first lid, the entrance and is gone out
Mouth is set in valve block;
The pressure valve module and direction valve module are inserted into valve block;
First lid is mounted on above the pressure valve module, and the control valve group and the first control oil circuit are set to the
One lid portion inside.
Based on the above technical solution, the pressure valve module and direction valve module are located at the opposite of the valve block
Both ends.
Based on the above technical solution, the valve body further includes the second lid being mounted on above the direction valve module
Second control oil circuit of body, the interior oil outlet being equipped with for being connected to the direction valve module of the second lid and control mouth, the second control
Liquefaction road is equipped with third damping structure.
Based on the above technical solution, in the valve block, the main oil gallery includes the import for being connected to the entrance
Main oil gallery, and the outlet main oil gallery of the connection outlet, import main oil gallery are respectively communicated with the pressure valve module and the side
To the oil inlet of valve module, the oil outlet that main oil gallery is respectively communicated with the pressure valve module and the direction valve module is exported.
Based on the above technical solution, the first control oil circuit is equipped with the second damping structure.
Based on the above technical solution, the control valve group is spill valve.
Based on the above technical solution, the cracking pressure P of the direction valve moduleaWith the unlatching pressure of control valve group
Power PcIt is adjustable.
The utility model also provides a kind of back pressure apparatus comprising:
Oil inlet pipe and oil outlet pipe;
Pressure valve, control valve and direction valve in parallel between oil inlet pipe and oil outlet pipe, the oil inlet of control valve with
By the first control oil communication between the control mouth of pressure valve, the is equipped between the oil inlet of control valve and the oil inlet pipe
One damping structure;
The cracking pressure P of the direction valveaThe cracking pressure P of≤control valvec, work as P-P2≥PbWhen, the pressure valve
It opens, wherein P is the oil pressure of the oil inlet pipe, P2For the pressure of the control mouth of the pressure valve, PbFor pressure threshold.
Compared with prior art, combination counterbalance valve provided by the embodiment of the utility model includes valve body, and is mounted on valve
Internal portion and by the pressure valve module of main oil gallery parallel connection, control valve group and direction valve module, valve body be equipped with entrance with out
Mouthful, valve inner is equipped with the main oil gallery of connection entrance and exit;The oil inlet of control valve group and the control mouth of pressure valve module
Between by first control oil communication, and between the oil inlet and entrance of control valve group be equipped with the first damping structure;Direction
The cracking pressure P of valve moduleaThe cracking pressure P of≤control valve groupc, work as P-P2≥PbWhen, pressure valve module is opened, and P is entrance
Oil pressure, P2For the control mouth pressure of pressure valve module, PbFor pressure threshold.
When the pressure of entrance increases to the cracking pressure P of direction valve moduleaWhen, oil return passes through the direction valve module stream opened
To outlet;When return pressure P continues to increase to control valve group unlatching, oil return mainly passes through pressure valve module and direction valve group
The outlet of part flow direction, and then return oil pressure is kept to and is stablized the pressure limit P in settinga(Pc+ Δ P) between, Δ P is first
Pressure drop caused by damping structure.When return flow changes in a big way, return oil pressure can be stablized, guarantee hydraulic system
Stability, and structure is simple, and use, installation and maintenance are more convenient.
Detailed description of the invention
Fig. 1 is the schematic diagram of the utility model embodiment combination counterbalance valve;
Fig. 2 is the enlarged diagram for the pressure valve module closed;
Fig. 3 is the schematic diagram of oil circuit in Fig. 1.
In figure:
1- valve body, 11- entrance, the outlet 12-, 13- main oil gallery, 131- import main oil gallery, 132- export main oil gallery, 133- the
One lid main oil gallery, 134- first control main oil gallery, and 135- second controls main oil gallery, 14- valve block, the first lid of 15-, 16- the
Two lids, 161- second control oil circuit, 162- third damping structure, 2- pressure valve module, 24- spool, 25- spring, 21- oil inlet
Chamber, 22- oil outlet chamber, 23- control chamber, 2A- oil inlet, 2B- oil outlet, 2C- control mouth, 3- control valve group, 31- first are damped
Structure, the direction 4- valve module, 5- first control oil circuit, and pressure oil road, the fuel-displaced survey pressure oil road 9- are surveyed in 8- oil inlet, and crimping is surveyed in 10- oil inlet
Head, the fuel-displaced pressure measuring tie-in of 20-.
Specific embodiment
With reference to the accompanying drawing and specific embodiment is described in further detail the utility model.
Shown in Figure 1, the utility model embodiment provides a kind of combination counterbalance valve, and combination counterbalance valve includes valve body 1, pressure
Power valve module 2, control valve group 3 and direction valve module 4, wherein valve body 1 is equipped with entrance 11 and outlet 12, sets inside valve body 1
There is the main oil gallery 13 of connection entrance 11 and outlet 12, pressure valve module 2, control valve group 3 and direction valve module 4 are installed in valve
It is inside body 1 and in parallel by main oil gallery 13.
It is connected between the oil inlet of control valve group 3 and the control mouth of pressure valve module 2 by the first control oil circuit 5, and
The first damping structure 31 is equipped between the oil inlet and entrance 11 of control valve group 3.
The cracking pressure P of direction valve module 4aThe cracking pressure P of≤control valve group 3c, work as P-P2≥PbWhen, pressure valve group
Part 2 is opened, wherein P is the oil pressure of entrance 11, P2For the control mouth pressure of pressure valve module 2, PbFor pressure threshold.
Preferably, valve body 1 includes valve block 14, the first lid 15 and the second lid 16, the first lid 15 and the second lid 16
It is installed in 14 surface of valve block, entrance 11 and outlet 12 are set in valve block 14.
Pressure valve module 2 and direction valve module 4 are inserted valve, are set in valve block 14 there are two plug-in opening, pressure valve module 2
It is inserted into the plug-in opening in valve block 14 respectively with direction valve module 4.Preferably, two plug-in openings are respectively arranged on the phase of valve block 14
Pair both ends, pressure valve module 2 and direction valve module 4 are located at the opposite both ends of valve block 14, guarantee the work of combination counterbalance valve
Stability.
Inserted valve mainly controls the on-off of oil circuit or the size of flow by the open amount between spool and valve pocket, inserting
The through-current capacity of valve is big, and valve core structure is simple, sensitive, good airproof performance.Pressure valve module 2 and direction valve module 4 are inserting
When valve, the through-current capacity for combining counterbalance valve is big, the hydraulic system big suitable for return flow.
Fig. 2 is the enlarged diagram for the pressure valve module 2 that do not open in Fig. 1, and pressure valve module 2 includes spool 24 and spring
25,24 both ends of spool have oil suction chamber 21 and control chamber 23 and the oil outlet chamber of spool side 22, wherein oil suction chamber 21 is located at
Spool bottom, control chamber 23 are located at the top of spool.Oil suction chamber 21 has oil inlet 2A, and oil outlet chamber 22 has oil outlet 2B, control
Chamber 23 has control mouth 2C.
Direction valve module 4 is similar to the structure of pressure valve module 2, and structure is simple, and simplification designs and manufactures, use, installation
It is more convenient with repairing, reduce cost.
Preferably, the first lid 15 is mounted on 2 top of pressure valve module, and control valve group 3 and the first control oil circuit 5 are all provided with
Inside the first lid 15, control valve group 3 is spill valve.
Shown in Figure 3, main oil gallery 13 is process on valve body 1.In valve block 14, main oil gallery 13 include be connected into
The import main oil gallery 131 of mouth 11, and the outlet main oil gallery 132 of connection outlet 12, import main oil gallery 131 are respectively communicated with pressure valve
The oil inlet A of the spool bottom of component 2 and direction valve module 4, outlet main oil gallery 132 are respectively communicated with pressure valve module 2 and direction
The oil outlet B of the spool side of valve module 4.I.e. entrance 11 by the outlet main oil gallery 131 inside valve block 14 with pressure valve group
The spool bottom of part 2 and the spool bottom of direction valve module 4 communicate, the spool side of pressure valve module 2 and direction valve module 4
Spool side passes through the outlet main oil gallery 132 inside valve block 14 and communicates with outlet 12.
Main oil gallery 13 further includes the first lid main oil gallery 133 in valve block 14 and the first lid 15, and is set to valve
The first control main oil gallery 134 and the second control main oil gallery 135 in block 14, the first damping structure 31 and control valve group 3 are all provided with
In on the first lid main oil gallery 133.There is first lid main oil gallery 133 import X1 and outlet Y1, import X1 to pass through the first control
Main oil gallery 134 is connected to import main oil gallery 131, and outlet Y1 passes through the second control connection of main oil gallery 135 outlet main oil gallery 132.
First control oil circuit 5 is equipped with the second damping structure 51, and the a1 mouth of the first control oil circuit 5 is connected to pressure valve module 2
Control mouth 2C.Preferably, control chamber 23 is opened on the connection surface of valve block 14 and the first lid 15, the first lid 15 and valve block
14 surround control chamber 23 jointly, simplify designing and manufacturing for pressure valve module 2, and use, installation and maintenance are more convenient, reduce
Cost.
Preferably, the second lid 16 is mounted on 4 top of direction valve module, is equipped with the side of connection in valve block 14 and the second lid 16
To the oil outlet of valve module 4 and the second control oil circuit 161 of control mouth, the second control oil circuit 161 is equipped with third damping structure
162.Specifically, the both ends of the second control oil circuit 161 in the second lid 16 are respectively X2 mouthfuls and a2 mouthfuls, third damping structure
162 are set between X2 mouthfuls and a2 mouthfuls, the oil outlet of X2 mouthfuls of communication direction valve modules 4, the control of a2 mouthfuls of communication direction valve modules 4
Mouthful.
Pressure of second damping structure 51 for the control chamber of steady pressure valve module 2, puts down so that pressure valve module 2 is opened
Surely, pressure of the third damping structure 162 for the control chamber of stabilising direction valve module 4, opens direction valve module 4 steadily.
First damping structure 31, the second damping structure 51 and third damping structure 162 are damping hole, specifically, first
Damping structure 31, the second damping structure 51 and third damping structure 162 are throttle hole.
Preferably, the cracking pressure P of direction valve module 4aWith the cracking pressure P of control valve group 3cIt is adjustable.
The fuel-displaced survey pressure oil road in pressure oil road 8 and connection outlet 12 is surveyed in the oil inlet that connection entrance 11 is additionally provided with inside valve block 14
9, oil inlet pressure measuring tie-in 10 is mounted on oil inlet and surveys in the threaded mounting hole in pressure oil road 8, and fuel-displaced pressure measuring tie-in 20 is mounted on fuel-displaced survey
In the threaded mounting hole in pressure oil road 9, it is preferred that oil inlet surveys pressure oil road 8 and is connected to import main oil gallery 131, and fuel-displaced survey pressure oil road 9 is connected to
Export main oil gallery 132.The oil pressure for measuring entrance 11 and outlet 12 aids in determining whether the working condition and pressure of combination counterbalance valve
Adjustment.
Combine the working principle of counterbalance valve are as follows:
The cracking pressure of direction valve module 4 is Pa, the cracking pressure of control valve group 3 is Pc, Pa≤Pc, it is preferred that PcSlightly
Greater than Pa.Work as P2=Pc, and P-P2≥PbWhen, pressure valve module 2 is opened, wherein P is the oil pressure of entrance 11, P2For pressure valve group
The control mouth pressure of part 2, pressure threshold PbAccording to maximum return flow, the direction valve of hydraulic system applied by combination counterbalance valve
The discharge characteristic of the flow and pressure valve module 2 of component 4 and control valve group 3 itself carries out matching selection.
When being much larger than control valve group 3 as the pressure valve module 2 of inserted valve and the latus rectum flow of direction valve module 4
When flow, the main function of control valve group 3 is the pilot control valve as pressure valve module 2, combines the max-flow of counterbalance valve
Amount is mainly determined according to the latus rectum flow of pressure valve module 2 and direction valve module 4, it may be assumed that latus rectum flow >=group of direction valve module 4
Maximum stream flow-direction valve module 4 latus rectum the flow for closing the entrance 11 of counterbalance valve, according to the latus rectum flow of direction valve module 4 and
The pressure-flow characteristic of its own can determine pressure threshold Pb。
In practical applications, the oil return of hydraulic system enters the entrance 11 of combination counterbalance valve, combines the entrance 11 of counterbalance valve
The maximum return flow of maximum stream flow, that is, hydraulic system.
When hydraulic system oil return, when 11 pressure P of entrance reaches the cracking pressure P of direction valve module 4a, direction valve module 4
Spool is opened, and hydraulic system oil return returns to the fuel tank of hydraulic system by entrance 11, direction valve module 4 and outlet 12, i.e., just
The return oil pressure for controlling hydraulic system to valve module 4 is Pa。
When the return flow of hydraulic system increases, the spool of direction valve module 4 is gradually opened into maximum open, therefore liquid
The return pressure P of pressure system will be also gradually increased with the increase of return flow, when return pressure P increases, so that control valve
When component 3 is opened, the part return flow of hydraulic system passes through the first control main oil gallery 134, the X1 mouth of the first lid 15, control
Valve module 3, Y1 mouthfuls and second control main oil gallery 135 be circulated to outlet 12.Due to the flowing of hydraulic oil, the X1 mouth of the first lid 15
Certain pressure drop Δ P will be generated to the first damping structure 31 between the oil inlet of control valve group 3, this will lead to pressure valve group
The pressure P of the oil suction chamber 21 of 2 spool bottom of part is greater than the pressure P of the control chamber 23 of pressure valve module 22P at this time2=Pc, when this two
A pressure difference value P-P2Meet and exceed PbWhen, i.e. P-P2≥Pb, the spool of pressure valve module 2 will open, the oil return of hydraulic system
The fuel tank of hydraulic system will be then flowed into mainly simultaneously by direction valve module 4 and the flow direction of pressure valve module 2 outlet 12.At this point,
The return oil pressure of hydraulic system is (Pc+ Δ P), PcFor the cracking pressure of control valve group 3, Δ P is that the first damping structure 31 causes
Pressure drop.
Therefore, above-mentioned plug-in combination counterbalance valve is able to solve the return flow due to hydraulic system in a wide range of interior variation
Brought return oil pressure fluctuates larger problem, and the return oil pressure of stable hydraulic system guarantees the stability of hydraulic system, and
And the structure for combining counterbalance valve is simple, use, installation and maintenance are more convenient.
Combine the above-mentioned pressure P of counterbalance valvea、PbAnd PcIt can be according to return flow variation range, the pressure of hydraulic system
The pressure flow characteristics auto of valve module 2, direction valve module 4 and control valve group 3 carries out matching selection, to adapt to different hydraulic pressure systems
The return flow variation range of system.
The utility model embodiment also provides a kind of back pressure apparatus, and back pressure apparatus includes oil inlet pipe, oil outlet pipe, and
Pressure valve, control valve and direction valve in parallel between oil inlet pipe and oil outlet pipe, the oil inlet of control valve and pressure valve
By the first control oil communication between control mouth, and the first damping structure is equipped between the oil inlet and oil inlet pipe of control valve
31′。
The cracking pressure P of direction valveaThe cracking pressure P of≤control valvec, work as P-P2≥PbWhen, pressure valve is opened, wherein P
For the oil pressure of oil inlet pipe, P2For the pressure of the control mouth of pressure valve, PbFor pressure threshold.
Back pressure apparatus can use existing pressure valve, pilot control valve and direction valve, it is preferred that pilot control valve is excessive
Flow valve.After pressure valve, pilot control valve are connected with direction valve by pipeline, when the return flow of hydraulic system is in scope of design
When variation, it is capable of the return oil pressure of stable hydraulic system, guarantees the stability of hydraulic system, and the structure letter of back pressure apparatus
Single, use, installation and maintenance are more convenient.
The utility model is not limited to above embodiment, for those skilled in the art, not
Under the premise of being detached from the utility model principle, several improvements and modifications can also be made, these improvements and modifications are also considered as this reality
Within novel protection scope.The content being not described in detail in this specification belongs to well known to professional and technical personnel in the field
The prior art.
Claims (10)
1. a kind of combination counterbalance valve, characterized in that it comprises:
Valve body (1) which is provided with entrance (11) and outlet (12), be equipped with inside valve body (1) and be connected to the entrance (11) and outlet
(12) main oil gallery (13);
Equipped with pressure valve module (2), control valve group (3) and the direction by main oil gallery (13) parallel connection inside the valve body (1)
Valve module (4), wherein pass through the first control oil between the oil inlet of control valve group (3) and the control mouth of pressure valve module (2)
Road (5) connection, and the first damping structure (31) are equipped between the oil inlet of control valve group (3) and the entrance (11);
The cracking pressure P of the direction valve module (4)aThe cracking pressure P of≤control valve group (3)c, work as P-P2≥PbWhen,
The pressure valve module (2) is opened, wherein P is the oil pressure of the entrance (11), P2For the control of the pressure valve module (2)
Mouth pressure, PbFor pressure threshold.
2. combination counterbalance valve as described in claim 1, it is characterised in that: the pressure valve module (2) and direction valve module (4)
It is inserted valve.
3. combination counterbalance valve as claimed in claim 2, it is characterised in that:
The valve body (1) includes connected valve block (14) and the first lid (15), and the entrance (11) and outlet (12) are set to
In valve block (14);
The pressure valve module (2) and direction valve module (4) are inserted on valve block (14);
First lid (15) is mounted on above the pressure valve module (2), the control valve group (3) and the first control oil circuit
(5) it is internal that the first lid (15) are set to.
4. combination counterbalance valve as claimed in claim 3, it is characterised in that: the pressure valve module (2) and direction valve module (4)
Positioned at the opposite both ends of the valve block (14).
5. combination counterbalance valve as claimed in claim 3, it is characterised in that: the valve body (1) further includes being mounted on the direction
The second lid (16) above valve module (4), the second lid (16) is interior to be equipped with for being connected to the fuel-displaced of the direction valve module (4)
Second control oil circuit (161) of mouth and control mouth, the second control oil circuit (161) are equipped with third damping structure (162).
6. combination counterbalance valve as claimed in claim 3, it is characterised in that: in the valve block (14), the main oil gallery (13)
Import main oil gallery (131) including being connected to the entrance (11), and the outlet main oil gallery (132) of the connection outlet (12),
Import main oil gallery (131) is respectively communicated with the oil inlet of the pressure valve module (2) and the direction valve module (4), exports main oil
Road (132) is respectively communicated with the oil outlet of the pressure valve module (2) and the direction valve module (4).
7. combination counterbalance valve as described in claim 1, it is characterised in that: first control oil circuit (5) is equipped with the second resistance
Buddhist nun's structure (51).
8. combination counterbalance valve as described in claim 1, it is characterised in that: the control valve group (3) is spill valve.
9. combination counterbalance valve as described in claim 1, it is characterised in that: the cracking pressure P of the direction valve module (4)aAnd control
The cracking pressure P of valve module (3) processedcIt is adjustable.
10. a kind of back pressure apparatus characterized by comprising
Oil inlet pipe and oil outlet pipe;
Pressure valve, control valve and direction valve in parallel between oil inlet pipe and oil outlet pipe, the oil inlet and pressure of control valve
By the first control oil communication between the control mouth of valve, the first resistance is equipped between the oil inlet of control valve and the oil inlet pipe
Buddhist nun's structure;
The cracking pressure P of the direction valveaThe cracking pressure P of≤control valvec, work as P-P2≥PbWhen, the pressure valve is opened,
Wherein, P is the oil pressure of the oil inlet pipe, P2For the pressure of the control mouth of the pressure valve, PbFor pressure threshold.
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CN201821842411.5U CN209212677U (en) | 2018-11-09 | 2018-11-09 | A kind of combination counterbalance valve and back pressure apparatus |
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CN201821842411.5U CN209212677U (en) | 2018-11-09 | 2018-11-09 | A kind of combination counterbalance valve and back pressure apparatus |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN109268331A (en) * | 2018-11-09 | 2019-01-25 | 中国船舶重工集团公司第七〇九研究所 | A kind of combination counterbalance valve and back pressure apparatus |
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2018
- 2018-11-09 CN CN201821842411.5U patent/CN209212677U/en active Active
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN109268331A (en) * | 2018-11-09 | 2019-01-25 | 中国船舶重工集团公司第七〇九研究所 | A kind of combination counterbalance valve and back pressure apparatus |
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