CN107740462A - Hydraulic control system and there is its excavator - Google Patents
Hydraulic control system and there is its excavator Download PDFInfo
- Publication number
- CN107740462A CN107740462A CN201711171217.9A CN201711171217A CN107740462A CN 107740462 A CN107740462 A CN 107740462A CN 201711171217 A CN201711171217 A CN 201711171217A CN 107740462 A CN107740462 A CN 107740462A
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- CN
- China
- Prior art keywords
- hydraulic
- control
- valve
- pressure
- control system
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000007246 mechanism Effects 0.000 claims abstract description 29
- 230000008520 organization Effects 0.000 claims abstract description 26
- 239000012530 fluid Substances 0.000 claims abstract description 18
- 239000002828 fuel tank Substances 0.000 claims abstract description 15
- 230000007935 neutral effect Effects 0.000 claims abstract description 15
- 230000009471 action Effects 0.000 claims abstract description 5
- 238000007599 discharging Methods 0.000 claims abstract 2
- 230000006837 decompression Effects 0.000 claims description 7
- 230000002950 deficient Effects 0.000 claims description 6
- 239000007788 liquid Substances 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 235000006508 Nelumbo nucifera Nutrition 0.000 description 1
- 240000002853 Nelumbo nucifera Species 0.000 description 1
- 235000006510 Nelumbo pentapetala Nutrition 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002706 hydrostatic effect Effects 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
- E02F9/20—Drives; Control devices
- E02F9/22—Hydraulic or pneumatic drives
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
- E02F9/20—Drives; Control devices
- E02F9/22—Hydraulic or pneumatic drives
- E02F9/2221—Control of flow rate; Load sensing arrangements
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
- E02F9/20—Drives; Control devices
- E02F9/22—Hydraulic or pneumatic drives
- E02F9/2264—Arrangements or adaptations of elements for hydraulic drives
- E02F9/2267—Valves or distributors
Abstract
The present invention provides a kind of hydraulic control system and has its excavator, and hydraulic control system includes：Multiple hydraulic actuators；Hydraulic pump, hydraulic power source of the hydraulic pump as multiple hydraulic actuators；Multiple control valves, multiple control valves are connected with multiple hydraulic actuators individually to control the action of multiple hydraulic actuators respectively；Operating mechanism, operating mechanism are connected with multiple control valves to control opening or closing for multiple control valves；Unloading valve, unloading valve is connected by off-load path with fuel tank to be back in fuel tank with the redundance for the fluid for discharging hydraulic pump, and the aperture area of unloading valve in its axial direction gradually increases or is gradually reduced from one end to the other side；Controlling organization, controlling organization are connected with unloading valve to control the size of the aperture area of unloading valve.Hydraulic control system according to embodiments of the present invention, when all control valves are in neutral position, oil return directly can be carried out by unloading valve, reduce return pressure.
Description
Technical field
The present invention relates to Work machine technical field, more particularly, to a kind of hydraulic control system and has the hydraulic pressure
The excavator of control system.
Background technology
Need to carry out overflow control in the work of hydraulic crawler excavator, ensure that the redundance of the discharge oil of pump may return to
In fuel tank.In general, the control by make the aperture area of overflow passage and the operational ton of operating mechanism correspondingly change and
Carry out, so overflow passage is often located in the control valve of each brake, but due to setting the overflow passage, cause the control
Valve processed is corresponding elongated on valve element direction of principal axis, improves cost and is unfavorable for assembling.
In existing hydraulic control system, when all control valve cores are in neutral position, the flow of pump output needs
Fuel tank is returned to by the centre by-pass oil circuit of the valve element of control valve, when system has multiple control valve elements, by neutrality
The pressure loss of logical oil circuit oil return can be bigger.And due to the electric proportional pressure-reducing valve using inverse proportion control, it is therefore desirable to set
Fail safe position is put to ensure to can continue to operation when hydraulic control system fails, adds the complicated journey of unloading valve design
Degree, and then increase manufacturing cost.
The content of the invention
In view of this, the present invention provides a kind of hydraulic control system.
The present invention also provides a kind of excavator with the hydraulic control system.
In order to solve the above technical problems, the present invention uses following technical scheme：
The hydraulic control system of embodiment according to a first aspect of the present invention, including：
Multiple hydraulic actuators；
Hydraulic pump, hydraulic power source of the hydraulic pump as multiple hydraulic actuators；
Multiple control valves, multiple control valves are connected more individually to control with multiple hydraulic actuators respectively
The action of the individual hydraulic actuator；
Operating mechanism, the operating mechanism be connected with multiple control valves with control the opening of multiple control valves or
Close；
Unloading valve, the fluid that the unloading valve is connected to discharge the hydraulic pump by off-load path with fuel tank it is unnecessary
Part is back in fuel tank, and the aperture area of the unloading valve in its axial direction gradually increases or gradually subtracted from one end to the other side
It is small；
Controlling organization, the controlling organization are connected with the unloading valve to control the big of the aperture area of the unloading valve
It is small.
Further, the hydraulic control system also includes：
Multiple pressure sensors, multiple pressure sensors are connected with multiple control valves respectively, each pressure
After force snesor measures the pressure of the corresponding control valve, pressure signal is transmitted to controller and exported according to controller
Control signal is inputted in the controlling organization and opened or closed by controlling organization control unloading valve.
Further, the controlling organization is formed as multiple pressure-reducing valves, and multiple pressure-reducing valves work in the control valve
When, according to the control pressure of the aperture area of the control valve regulation pressure-reducing valve.
Further, the pressure-reducing valve is electric proportional pressure-reducing valve.
Further, the pressure-reducing valve is direct proportion pressure-reducing valve.
Further, the unloading valve is opened when multiple control valves are in neutral position carries out oil return to reduce
The pressure loss of oil return.
Further, the hydraulic control system also includes：
Fail-safe mechanism, the fail-safe mechanism are connected with the control valve with the decompression defective valve time control system
The unloading valve in fail-safe condition and maintains the normal operation of the fluid of the hydraulic control system automatically.
Further, the hydraulic pump is formed as variable capacity type hydraulic pump, the hydraulic pump be connected with pump control mechanism with
The discharge rate of the fluid of the hydraulic pump is controlled by the pump control mechanism.
The excavator of embodiment according to a second aspect of the present invention, including the hydraulic control system according to above-described embodiment
System.
The above-mentioned technical proposal of the present invention has the beneficial effect that：
Hydraulic control system according to embodiments of the present invention, when all control valves are in neutral position, can directly it lead to
Cross unloading valve and carry out oil return, reduce return pressure, and the input letter that the hydraulic control system obtains for different hydraulics
Number, controlling organization and unloading valve can export corresponding control pressure, realize control to unloading valve aperture area and to liquid
The control of pump displacement, meet the flow needed for the hydraulic control system, in addition, the hydraulic control system is provided with fail safe machine
Structure, in fail-safe condition and the fluid of the hydraulic control system is maintained just automatically in decompression defective valve time control unloading valve
Often operation.
Brief description of the drawings
Fig. 1 is the circuit structure figure of the hydraulic control system of the embodiment of the present invention.
Reference：
Hydraulic control system 100；
Hydraulic actuator 10；
Hydraulic pump 20；Pump control mechanism 21；
Control valve 30；Neutral path 31；
Operating mechanism 40；Pressure sensor 41；
Unloading valve 50；Off-load path 51；
Controlling organization 60；
Fail-safe mechanism 70；
Controller 80；
Fuel tank 90.
Embodiment
To make the purpose, technical scheme and advantage of the embodiment of the present invention clearer, below in conjunction with the embodiment of the present invention
Accompanying drawing, the technical scheme of the embodiment of the present invention is clearly and completely described.Obviously, described embodiment is this hair
Bright part of the embodiment, rather than whole embodiments.Based on described embodiments of the invention, ordinary skill
The every other embodiment that personnel are obtained, belongs to the scope of protection of the invention.
Hydraulic control system 100 according to embodiments of the present invention is specifically described with reference to accompanying drawing first below.
As shown in figure 1, hydraulic control system 100 according to embodiments of the present invention includes multiple hydraulic actuators 10, hydraulic pressure
Pump 20, multiple control valves 30, operating mechanism 40, unloading valve 50 and controlling organization 60.
Specifically, hydraulic power source of the hydraulic pump 20 as multiple hydraulic actuators 10, multiple control valves 30 respectively with it is multiple
Hydraulic actuator 10 is connected individually to control the action of multiple hydraulic actuators 10, operating mechanism 40 and multiple control valves 30
It is connected to control opening or closing for multiple control valves 30, unloading valve 50 is connected by off-load path 51 with fuel tank 90 with by hydraulic pressure
The redundance of fluid that pump 20 is discharged is back in fuel tank 90, and the aperture area of unloading valve 50 in its axial direction is from one end to another
One end gradually increases or is gradually reduced, and controlling organization 60 is connected with unloading valve 50 to control the big of the aperture area of unloading valve 50
It is small.
In other words, hydraulic control system 100 according to embodiments of the present invention is mainly by multiple hydraulic actuators 10, hydraulic pump
20th, multiple control valves 30, operating mechanism 40, unloading valve 50 and controlling organization 60 form.Hydraulic pump 20 can be used as multiple hydraulic pressure
The hydraulic power source of actuator 10, multiple control valves 30 can be connected with multiple hydraulic actuators 10 respectively, and each control valve 30 can be with
Individually hydraulic actuator 10 corresponding to control works, and each control valve 30 can be connected in series in fuel tank 90 by neutral path 31
On.Control valve 30 can be connected with operating mechanism 40, and operating mechanism 40 can be formed as corresponding with each control valve 30 and be remotely controlled
Valve, opening or closing for corresponding control valve 30 is controlled by remote-controlled valve.
Unloading valve 50 can be connected on fuel tank 90 by off-load path 51, and the opening of unloading valve 50 can be from one end to another
One end gradually increases or is gradually reduced, and controlling organization 60 can be connected with unloading valve 50, and controlling organization 60 can control unloading valve
The size of 50 aperture area.When all control valves 30 of hydraulic control system 100 are in neutral position, hydraulic pump 20 exports
Fluid fuel tank 90 no longer can be returned to by the neutral path 31 in control valve 30, but unloading on unloading valve 50 can be passed through
Lotus path 51 is returned directly in fuel tank 90, effectively reduces the pressure loss of the neutral position oil return of control valve 30.
Thus, hydraulic control system 100 according to embodiments of the present invention, when all control valves 30 are in neutral position,
Oil return directly can be carried out by unloading valve 50, reduce return pressure.
According to one embodiment of present invention, hydraulic control system 100 also includes multiple pressure sensors 41.
Specifically, multiple pressure sensors 41 are connected with multiple control valves 30 respectively, and each pressure sensor 41 measures phase
After the pressure for the control valve 30 answered, the control signal that pressure signal is transmitted to controller 80 and exported according to controller 80 is inputted
Unloading valve 50 is controlled to open or close in controlling organization 60 and by controlling organization 60.
That is, hydraulic control system 100 can also include multiple pressure sensors 41.Multiple pressure sensors 41 can
To be connected respectively with multiple control valves 30, when hydraulic control system 100 works, each hydrostatic sensor can cut pressure signal
Change in corresponding control valve 30, after the pressure for measuring corresponding control valve 30, pressure signal can be passed on controller 80,
Controller 80 can carry out calculating analysis to the pressure signal received, ensure that controller 80 can fast and accurately judge liquid
Working condition residing for pressure control system 100.The control signal exported after analysis is calculated according to controller 80 and inputs controlling organization
In 60, the corresponding control signal control unloading valve 50 received finally by controlling organization 60 opens or closes, and realizes to off-load
Required fluid amount when the control of valve 50 is to obtain the work of hydraulic control system 100.
In certain specific embodiments of the invention, controlling organization 60 is formed as multiple pressure-reducing valves, and multiple pressure-reducing valves exist
When control valve 30 works, the control pressure of pressure-reducing valve is adjusted according to the aperture area of control valve 30.
In other words, controlling organization 60 can be formed as multiple pressure-reducing valves, and each pressure-reducing valve, can when control valve 30 works
To adjust the control pressure of pressure-reducing valve according to the aperture area of control valve 30, the control to unloading valve 50 is realized to obtain hydraulic pressure control
System 100 processed fluid amount required when working.
According to one embodiment of present invention, pressure-reducing valve is electric proportional pressure-reducing valve.
That is, pressure-reducing valve can use electric proportional pressure-reducing valve, it is easy to the control of pressure-reducing valve to install, electric proportional pressure-reducing valve
Service life is grown, and production cost is relatively low, and control performance is sensitive.
In certain specific embodiments of the invention, pressure-reducing valve is direct proportion pressure-reducing valve.
In other words, pressure-reducing valve can use direct proportion pressure-reducing valve, and direct proportion pressure-reducing valve can be in each control valve 30
When valve element is in neutral position, the control electric current of control valve 30 is maximum, the control pressure of output is maximum, while unloading valve 50 is opened
Open area is maximum, and when the valve element action of control valve 30, the control electric current of control valve 30 is reduced, and the control pressure of output reduces,
The aperture area of unloading valve 50 is also gradually reduced simultaneously.The complexity of the design of unloading valve 50 is reduced by using direct proportion pressure-reducing valve
Degree, reduce manufacturing cost.
According to one embodiment of present invention, unloading valve 50 can be opened when multiple control valves 30 are in neutral position
Oil return is carried out to reduce the pressure loss of oil return.
In certain specific embodiments of the invention, hydraulic control system 100 also includes abating protection device.
Specifically, fail-safe mechanism 70 is connected with control valve 30 to locate automatically in decompression defective valve time control unloading valve 50
In fail-safe condition and maintain the normal operation of the fluid of hydraulic control system 100.
That is, hydraulic control system 100 can also include abating protection device.Fail-safe mechanism 70 can and be controlled
Valve 30 processed is connected, and abating protection device can be in fail-safe condition automatically in decompression defective valve time control unloading valve 50, tie up
Hold the normal operation of the fluid of hydraulic control system 100.
According to one embodiment of present invention, hydraulic pump 20 is formed as variable capacity type hydraulic pump, and hydraulic pump 20 is adjusted with pump
Section device 21 is connected to control the discharge rate of the fluid of hydraulic pump 20 by pump control mechanism 21.
In other words, hydraulic pump 20 can use variable capacity type hydraulic pump, and hydraulic pump 20 can be with the phase of pump control mechanism 21
Even, the discharge rate of the fluid of hydraulic pump 20 is controlled by pump control mechanism 21, saves the discharge of fluid in hydraulic control system 100
Amount, job costs are reduced, save the energy.
Sum it up, hydraulic control system 100 according to embodiments of the present invention, neutral position is in all control valves 30
When, oil return directly can be carried out by unloading valve 50, reduce return pressure, and the hydraulic control system 100 is directed to different liquid
The input signal that press strip part obtains, controlling organization 60 and unloading valve 50 can export corresponding control pressure, realize to unloading valve
The control of 50 aperture areas and the control to the discharge capacity of hydraulic pump 20, meet the flow needed for the hydraulic control system 100, this
Outside, the hydraulic control system 100 is provided with fail-safe mechanism 70, in decompression defective valve time control unloading valve 50 automatically in failure
Guard mode and the normal operation for maintaining the fluid of the hydraulic control system 100.
Excavator according to a second aspect of the present invention includes the hydraulic control system 100 in above-described embodiment, due to basis
The hydraulic control system 100 of the embodiment of the present invention has above-mentioned technique effect, therefore excavator according to embodiments of the present invention
With corresponding technique effect, i.e., when all control valves 30 are in neutral position, directly can be returned by unloading valve 50
Oil, reduce return pressure.
The other structures of excavator according to embodiments of the present invention and operation are all to those skilled in the art can
With what is understood and easily realize, therefore it is not described in detail.
Described above is the preferred embodiment of the present invention, it is noted that for those skilled in the art
For, on the premise of principle of the present invention is not departed from, some improvements and modifications can also be made, these improvements and modifications
It should be regarded as protection scope of the present invention.
Claims (9)
- A kind of 1. hydraulic control system, it is characterised in that including：Multiple hydraulic actuators；Hydraulic pump, hydraulic power source of the hydraulic pump as multiple hydraulic actuators；Multiple control valves, multiple control valves are connected with multiple hydraulic actuators individually to control multiple institutes respectively State the action of hydraulic actuator；Operating mechanism, what the operating mechanism was connected to control multiple control valves with multiple control valves plays on or off Close；Unloading valve, the unloading valve are connected with the redundance for the fluid for discharging the hydraulic pump by off-load path with fuel tank It is back in fuel tank, the aperture area of the unloading valve in its axial direction gradually increases or is gradually reduced from one end to the other side；Controlling organization, the controlling organization are connected with the unloading valve to control the size of the aperture area of the unloading valve.
- 2. hydraulic control system according to claim 1, it is characterised in that also include：Multiple pressure sensors, multiple pressure sensors are connected with multiple control valves respectively, and each pressure passes After sensor measures the pressure of the corresponding control valve, pressure signal is transmitted to controller and according to the control of controller output Signal is inputted in the controlling organization and opened or closed by controlling organization control unloading valve.
- 3. hydraulic control system according to claim 2, it is characterised in that the controlling organization is formed as multiple decompressions Valve, multiple pressure-reducing valves adjust the pressure-reducing valve when the control valve works, according to the aperture area of the control valve Control pressure.
- 4. hydraulic control system according to claim 3, it is characterised in that the pressure-reducing valve is electric proportional pressure-reducing valve.
- 5. hydraulic control system according to claim 4, it is characterised in that the pressure-reducing valve is direct proportion pressure-reducing valve.
- 6. hydraulic control system according to claim 3, it is characterised in that the unloading valve is equal in multiple control valves Opened during in neutral position and carry out oil return to reduce the pressure loss of oil return.
- 7. hydraulic control system according to claim 3, it is characterised in that also include：Fail-safe mechanism, the fail-safe mechanism are connected with the control valve with described in the decompression defective valve time control system Unloading valve in fail-safe condition and maintains the normal operation of the fluid of the hydraulic control system automatically.
- 8. hydraulic control system according to claim 1, it is characterised in that the hydraulic pump is formed as variable capacity type liquid Press pump, the hydraulic pump are connected with pump control mechanism to control the discharge rate of the fluid of the hydraulic pump by the pump control mechanism.
- 9. a kind of excavator, it is characterised in that including the hydraulic control system any one of claim 1-8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711171217.9A CN107740462A (en) | 2017-11-22 | 2017-11-22 | Hydraulic control system and there is its excavator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711171217.9A CN107740462A (en) | 2017-11-22 | 2017-11-22 | Hydraulic control system and there is its excavator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107740462A true CN107740462A (en) | 2018-02-27 |
Family
ID=61239119
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711171217.9A Pending CN107740462A (en) | 2017-11-22 | 2017-11-22 | Hydraulic control system and there is its excavator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107740462A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109695599A (en) * | 2019-01-31 | 2019-04-30 | 广西柳工机械股份有限公司 | Variable delivery hydraulic system, pump output flow control method, engineering machinery |
| CN114207293A (en) * | 2019-08-23 | 2022-03-18 | 川崎重工业株式会社 | Hydraulic system for construction machine |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1550617A (en) * | 2003-05-15 | 2004-12-01 | ��ֽ����е��ʽ���� | Hydraulic controller for working machine |
| CN1676785A (en) * | 2004-03-31 | 2005-10-05 | 神钢建设机械株式会社 | Hydraulic control device and construction machine |
| CN101230869A (en) * | 2007-01-24 | 2008-07-30 | 神钢建设机械株式会社 | Hydraulic control device of construction machine |
-
2017
- 2017-11-22 CN CN201711171217.9A patent/CN107740462A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1550617A (en) * | 2003-05-15 | 2004-12-01 | ��ֽ����е��ʽ���� | Hydraulic controller for working machine |
| CN1676785A (en) * | 2004-03-31 | 2005-10-05 | 神钢建设机械株式会社 | Hydraulic control device and construction machine |
| CN101230869A (en) * | 2007-01-24 | 2008-07-30 | 神钢建设机械株式会社 | Hydraulic control device of construction machine |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109695599A (en) * | 2019-01-31 | 2019-04-30 | 广西柳工机械股份有限公司 | Variable delivery hydraulic system, pump output flow control method, engineering machinery |
| CN114207293A (en) * | 2019-08-23 | 2022-03-18 | 川崎重工业株式会社 | Hydraulic system for construction machine |
| CN114207293B (en) * | 2019-08-23 | 2023-07-18 | 川崎重工业株式会社 | Hydraulic system for construction machine |
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Application publication date: 20180227 |
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