CN108179781A - Loader hydraulic control system - Google Patents
Loader hydraulic control system Download PDFInfo
- Publication number
- CN108179781A CN108179781A CN201810096196.7A CN201810096196A CN108179781A CN 108179781 A CN108179781 A CN 108179781A CN 201810096196 A CN201810096196 A CN 201810096196A CN 108179781 A CN108179781 A CN 108179781A
- Authority
- CN
- China
- Prior art keywords
- valve
- connect
- fluid port
- hydraulic fluid
- oil outlet
- 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.)
- Withdrawn
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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
- E02F9/2264—Arrangements or adaptations of elements for hydraulic drives
- E02F9/2267—Valves or distributors
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F3/00—Dredgers; Soil-shifting machines
- E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
- E02F3/28—Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets
- E02F3/36—Component parts
- E02F3/42—Drives for dippers, buckets, dipper-arms or bucket-arms
-
- 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
Abstract
The invention discloses a kind of loader hydraulic control systems, belong to engineering machinery hydraulic control technology field.It solves the defects of larger wasted power existing for conventional load machine hydraulic system in the prior art, production and the of high cost and complete machine equipment settling amount of later maintenance reduce.Its agent structure includes working barrel, fuel tank, pilot valve, duplex pump, work system and steering, work system is connect respectively with working barrel and pilot valve, duplex pump is connect with steering, working barrel is respectively connected to duplex pump in fuel tank, the loader hydraulic control system includes shuttle valve, guide's pressure reducing valve and accumulator, the hydraulic fluid port P1 of shuttle valve and the oil outlet pipeline of working barrel connect, and the oil outlet pipeline of hydraulic fluid port P2 and duplex pump connects, and hydraulic fluid port P3 is connect with the oil inlet of guide's pressure reducing valve；The oil outlet of guide's pressure reducing valve is connect respectively with pilot valve and accumulator.Present invention is mainly used in loader hydraulic system.
Description
Technical field：
The invention belongs to engineering machinery hydraulic control technology field, specifically, more particularly to a kind of loader hydraulic control
System processed.
Background technology：
In engineering machinery, loading machine generally carries out spading operation and loading operation, and complete machine is frequently completed left and right turn, received
The actions such as bucket, lifting, discharging, these are required for hydraulic system and are realized to control；It is general in existing loader hydraulic system
It is made of machining device hydraulic system, steering hydraulic system.
Under normal circumstances, the working barrel in machining device hydraulic system is supplied separately to the rotary ink tank in equipment and act
Oil-lifting jar, steering pump are supplied separately to steering cylinder, this to be independently supplied system to be easy to cause the working barrel in emergence operating mode defeated
Go out most of flow and be in overflow situation, wasted power is larger；Using when not turning to, steering pump is collaborated into supply work system
Converging system, in emergence operating mode, also can there are power loss it is excessive the phenomenon that (in emergence operating mode, system needs pressure,
Flow demand is relatively fewer, at this point, the rotating speed of engine is in highest state, the output flow of working barrel and steering pump is very big),
And need especially to optimize hydraulic pressure heat dissipation, otherwise hydraulic oil temperature can not ensure, and can increase hydraulic oil and dissipate
Back pressure, the damage failure risk that hydraulic oil is caused to dissipate.If using pilot control system, the guide oil of pilot control hydraulic system
Source derives from pioneer pump, and the presence of pioneer pump increases the loss of power, and the maintenance cost in later stage can increase.It is selected using pressure
The pilot system of valve arrangement although realizing after complete machine is stopped working, can still make boom cylinder drop back into ground, due to pressure
Selector valve is connected with boom cylinder rodless cavity, can lead to the internal leakage of boom cylinder, reduces and is settled about complete machine equipment
The requirement of amount.
Invention content：
In order to solve larger power loss existing for conventional load machine hydraulic system in the prior art, production and later maintenance
Of high cost and complete machine equipment settling amount the shortcomings that reducing, the present invention provides a kind of loadings for being different from the prior art
Machine hydraulic control system, production is low with the cost of later maintenance, reduces power loss, increases the tractive force of engine, and protect
The settling amount of equipment is demonstrate,proved.
To achieve these goals, realization that the present invention adopts the following technical solutions：
A kind of loader hydraulic control system, including working barrel, fuel tank, pilot valve, duplex pump, work system and steering system
System, work system are connect respectively with working barrel and pilot valve, and duplex pump is connect with steering, and working barrel connects respectively with duplex pump
Enter in fuel tank, the loader hydraulic control system includes shuttle valve, guide's pressure reducing valve and accumulator, hydraulic fluid port P1 and the work of shuttle valve
The oil outlet pipeline of the oil outlet pipeline connection of pump, hydraulic fluid port P2 and duplex pump connects, the oil inlet of hydraulic fluid port P3 and guide's pressure reducing valve
Connection；The oil outlet of guide's pressure reducing valve is connect respectively with pilot valve and accumulator.
Further, the loader hydraulic control system includes flow signal valve, flow conversion control valve and unloading valve,
The oil outlet of the hydraulic fluid port P6 of flow signal valve and the right side pump of duplex pump connects, the hydraulic fluid port P2 connections of hydraulic fluid port Pr and shuttle valve, hydraulic fluid port
Po is connect with steering；The hydraulic fluid port P4 of unloading valve and the oil outlet pipeline of working barrel connect, hydraulic fluid port P5 and flow conversion and control
The hydraulic fluid port Pw connections of valve；The hydraulic fluid port P7 of flow conversion control valve and the oil outlet of the left pump of duplex pump connect, hydraulic fluid port Ps accesses
In the pipeline that flow signal valve is connect with steering.
Further, the work system includes multi-way valve, boom cylinder and rotary ink tank, and multi-way valve is oily with swing arm respectively
Cylinder is connected with rotary ink tank, and pilot valve sends pressure signal to each connection valve of multi-way valve.
Further, the steering includes pressure-gradient control valve, steering gear and steering cylinder, the oil inlet of pressure-gradient control valve respectively with
Flow conversion control valve is connected with flow signal valve, and oil outlet is connect with steering gear, and steering gear is also connect with steering cylinder.
Further, the loader hydraulic control system include radiator and oil return filter core, the oil inlet of radiator with
Pressure-gradient control valve connects, and oil outlet is connect with the oil inlet of oil return filter core, and the oil outlet of oil return filter core is connect with fuel tank.
Further, the loader hydraulic control system further includes filter, and oil inlet and the guide of filter are depressurized
The oil outlet connection of valve, oil outlet are connect with pilot valve.
Compared with prior art, the beneficial effects of the invention are as follows：
1st, using shuttle valve, the output flow that guide's energy source comes from working barrel and duplex pump is realized, pressure is big
As pilot control, make design, production and the cost reduction of later maintenance；
2nd, it is realized by unloading valve and declines low power loss in emergence working condition, increase the work of the tractive force of engine
With, and its power loss can reduce 25KW；
3rd, using flow conversion control valve and flow signal valve, the power loss of hydraulic system is reduced, power loss can
Reduce 5KW；
4th, using guide's pressure reducing valve and accumulator, it ensure that the settling amount of equipment.
Description of the drawings：
Fig. 1 is the structural diagram of the present invention；
Fig. 2 is the partial enlarged view at H in Fig. 1；
Fig. 3 is the partial enlarged view at K in Fig. 1.
In figure：1st, working barrel；2nd, hydraulic oil container；3rd, unloading valve；4th, filter；5th, shuttle valve；6th, guide's pressure reducing valve；7th, accumulation of energy
Device；8th, pilot valve；9th, flow conversion control valve；10th, flow signal valve；11st, duplex pump；12nd, radiator；13rd, pressure-gradient control valve；14、
Steering gear；15th, steering cylinder；16th, multi-way valve；17th, boom cylinder；18th, rotary ink tank；19th, oil return filter core；20th, damping hole；
21st, check valve.
Specific embodiment：
Below by specific embodiment and with reference to attached drawing, the invention will be further described.
Embodiment 1：
As shown in Figure 1, a kind of loader hydraulic control system, including working barrel 1, fuel tank 2, pilot valve 8, duplex pump 11,
Work system and steering, work system are connect by pipeline with working barrel 1 and pilot valve 8 respectively, and duplex pump 11 is with turning to
System connects, and working barrel 1 is respectively connected to duplex pump 11 in fuel tank 2, and the loader hydraulic control system includes shuttle valve 5, elder generation
Pressure reducing valve 6 and accumulator 7 are led, the hydraulic fluid port P1 of shuttle valve 5 is connect with the oil outlet pipeline of working barrel 1, hydraulic fluid port P2 and duplex pump 11
Oil outlet pipeline connects, and hydraulic fluid port P3 is connect with the oil inlet of guide's pressure reducing valve 6；The oil outlet of guide's pressure reducing valve 6 respectively with guide
Valve 8 and accumulator 7 connect.
Embodiment 2：
A kind of loader hydraulic control system, including flow signal valve 10, flow conversion control valve 9 and unloading valve 3, flow
The hydraulic fluid port P6 of signal valve 10 is connect with the oil outlet that the right side of duplex pump 11 pumps, and hydraulic fluid port Pr is connect with the hydraulic fluid port P2 of shuttle valve 5, hydraulic fluid port
Po is connect with steering；The hydraulic fluid port P4 of unloading valve 3 is connect with the oil outlet pipeline of working barrel 1, and hydraulic fluid port P5 is controlled with flow conversion
The hydraulic fluid port Pw connections of valve 9 processed；The hydraulic fluid port P7 of flow conversion control valve 9 is connect with the oil outlet of the left pump of duplex pump 11, hydraulic fluid port
In the pipeline that Ps access flows signal valve 10 is connect with steering.Other parts are same as Example 1.
Embodiment 3：
A kind of loader hydraulic control system, work system includes multi-way valve 16, boom cylinder 17 and rotary ink tank 18, more
Road valve 16 is connect respectively with boom cylinder 17 and rotary ink tank 18, and pilot valve 8 sends pressure signal to each connection valve of multi-way valve 16.
The steering includes pressure-gradient control valve 13, steering gear 14 and steering cylinder 15, and the oil inlet of pressure-gradient control valve 13 is converted respectively with flow
Control valve 9 and flow signal valve 10 connect, and oil outlet is connect with steering gear 14, and steering gear 14 is also connect with steering cylinder 15；Institute
It states loader hydraulic control system and includes radiator 12 and oil return filter core 19, the oil inlet of radiator 12 is connect with pressure-gradient control valve 13,
Oil outlet is connect with the oil inlet of oil return filter core 19, and the oil outlet of oil return filter core 19 is connect with fuel tank 2；The loader hydraulic control
System processed further includes filter 4, and the oil inlet of filter 4 is connect with the oil outlet of guide's pressure reducing valve 6, oil outlet and pilot valve 8
Connection.Other parts are same as Example 2.
Action process and principle at work of the invention is as follows：
When complete machine just starts, work system does not establish pressure, at this time steering wheel rotation, is driven and turned to by steering wheel
Device 14, steering establishes pressure for entire hydraulic control system, and by the pressure comparison of shuttle valve 5, the big conduct of pressure power is first
Oil Guide source provides pressure for guide's pressure reducing valve 6, the work pressure needed for pressure reduction to pilot system is made by guide's pressure reducing valve 6
Power range supplies pilot valve 8 using filter 4 and works, in order to ensure the reliability and stability of pilot system, depressurized through guide
After valve 6, accumulator 7 of connecting, accumulator 7 provides stable oil sources for pilot valve 8.It is equipped between accumulator 7 and guide's pressure reducing valve 6
Check valve 21 when can prevent the work system of 5 front end of shuttle valve or steering no pressure, ensures that pilot valve 8 has reservoir pressure.Cause
This, when complete machine is stopped, accumulator 7 provides oil sources for pilot valve 8, ensures that swing arm can drop back into safely ground, the liquid of pilot valve 8
Pressure oil liquid pushes the main valve plug of multi-way valve 16 that equipment is made to generate corresponding action.
Signified pilot system includes pilot valve 8, filter 4, guide's pressure reducing valve 6 and shuttle valve 5 in text.
Restart after shutdown, the pressure supply pilot valve 8 laid in accumulator 7 is so as to push the main valve plug of multi-way valve 16 to transport
It is dynamic so that equipment generates corresponding action.At this point, working barrel 1 produces pressure, by the pressure comparison of shuttle valve 5, hydraulic pressure
Fluid supplies accumulator 7 after the decompression of guide's pressure reducing valve 6, and resupplying pilot valve 8 by accumulator 7 is used as pilot control, entirely
Hydraulic control system constantly recycles the above process.
Due to eliminating pressure selection valve, so there is no the fluid in boom cylinder 17 from pressure selection valve internal leakage
Problem, therefore the settling amount of swing arm is more secure；Pioneer pump is eliminated simultaneously, reduces the power loss of hydraulic system.
It, can using duplex pump 11 by increasing flow conversion control valve 9, flow signal valve 10, duplex pump 11 and unloading valve 3
Reduce the discharge capacity of working barrel 1 and duplex pump 11；Flow signal valve 10 is obtained pressure difference signal, is used by in-between damping hole 20
The spool of flow conversion control valve 9 to be controlled to move.When low engine speeds, since 10 both ends pressure difference of flow signal valve is small
(pressure of Pr and Pro are of substantially equal), the right end of flow conversion control valve 9 are more than the power of left end plus spring force, so, flow
Switchover control valve 9 is in right end, right position work, at this point, left pump in duplex pump 11, is arrived by the interflow of flow conversion control valve 9
In steering, when needing to turn to, while steering is supplied, for meeting the flow demand of steering；Work as engine
When running at high speed, due to that can meet the needs of steering is to flow using the right side pump in duplex pump 11, so, it will be left
Side pump is for collaborating to arrive work system, so as to reduce the discharge capacity of working barrel 1, due to the big (Pr- of 10 both ends pressure difference of flow signal valve
Pro >=0), the right end of flow conversion control valve 9 is less than the power of left end plus spring force, so, flow conversion control valve 9 is in
Left end, left position work, at this point, the left pump in duplex pump 11 collaborates in work system (to lead to by flow conversion control valve 9
It crosses in hydraulic fluid port P5, hydraulic fluid port the P4 interflow to the oil outlet pipeline of working barrel 1 of unloading valve 3).
When emergence operating mode (work system pressure is more than the pressure of unloading valve 3), work system does not need to big flow, off-load
Left pump in duplex pump 11 is returned to hydraulic oil container 2 by valve 3 by hydraulic fluid port P5 and the direct pressure releases of hydraulic fluid port T, reduces hydraulic control system
The power loss of system reduces energy loss, and it is the torque that gearbox provides to increase engine, and in emergence operating mode, increase is led
The effect of gravitation.
In emergence operating mode, the rotating speed highest of engine, at this point, the right side pump in duplex pump 11 can meet steering
Demand to flow, so not needing to go supply steering with the left pump in duplex pump 11；If in addition, in emergence operating mode
Left pump is supplied into steering, then remove radiator 12 by pressure-gradient control valve 13 simultaneously, since flow is big, the back of the body that hydraulic oil can be caused to dissipate
Pressure is especially high, increases hydraulic oil and scatters the risk split.
During non-emergence operating mode (system pressure does not reach the pressure of unloading valve 3), the left pump interflow in duplex pump 11 is arrived
(collaborated in work system by the hydraulic fluid port P5 of unloading valve 3, hydraulic fluid port P4 into the oil outlet pipeline of working barrel 1).
Claims (6)
1. a kind of loader hydraulic control system, including working barrel (1), fuel tank (2), pilot valve (8), duplex pump (11), work
System and steering, work system are connect respectively with working barrel (1) and pilot valve (8), and duplex pump (11) connects with steering
It connects, working barrel (1) is respectively connected to duplex pump (11) in fuel tank (2), it is characterised in that：The loader hydraulic control system packet
Shuttle valve (5), guide's pressure reducing valve (6) and accumulator (7) are included, the hydraulic fluid port P1 of shuttle valve (5) connects with the oil outlet pipeline of working barrel (1)
It connects, hydraulic fluid port P2 is connect with the oil outlet pipeline of duplex pump (11), and hydraulic fluid port P3 is connect with the oil inlet of guide's pressure reducing valve (6)；Guide
The oil outlet of pressure reducing valve (6) is connect respectively with pilot valve (8) and accumulator (7).
2. loader hydraulic control system according to claim 1, it is characterised in that：The loader hydraulic control system
Including flow signal valve (10), flow conversion control valve (9) and unloading valve (3), the hydraulic fluid port P6 and duplex of flow signal valve (10)
The oil outlet connection of the right side pump of (11) is pumped, hydraulic fluid port Pr is connect with the hydraulic fluid port P2 of shuttle valve (5), and hydraulic fluid port Po is connect with steering；
The hydraulic fluid port P4 of unloading valve (3) is connect with the oil outlet pipeline of working barrel (1), the hydraulic fluid port of hydraulic fluid port P5 and flow conversion control valve (9)
Pw connections；The hydraulic fluid port P7 of flow conversion control valve (9) is connect with the oil outlet of the left pump of duplex pump (11), hydraulic fluid port Ps incoming streams
In the pipeline that amount signal valve (10) is connect with steering.
3. loader hydraulic control system according to claim 2, it is characterised in that：The work system includes multi-way valve
(16), boom cylinder (17) and rotary ink tank (18), multi-way valve (16) connect respectively with boom cylinder (17) and rotary ink tank (18)
It connects, pilot valve (8) sends pressure signal to each connection valve of multi-way valve (16).
4. loader hydraulic control system according to claim 3, it is characterised in that：The steering includes pressure-gradient control valve
(13), steering gear (14) and steering cylinder (15), the oil inlet of pressure-gradient control valve (13) respectively with flow conversion control valve (9) and flow
Signal valve (10) connects, and oil outlet is connect with steering gear (14), and steering gear (14) is also connect with steering cylinder (15).
5. loader hydraulic control system according to claim 4, it is characterised in that：The loader hydraulic control system
Including radiator (12) and oil return filter core (19), the oil inlet of radiator (12) is connect with pressure-gradient control valve (13), oil outlet and oil return
The oil inlet connection of filter core (19), the oil outlet of oil return filter core (19) are connect with fuel tank (2).
6. loader hydraulic control system according to claim 5, it is characterised in that：The loader hydraulic control system
Filter (4) is further included, the oil inlet of filter (4) is connect with the oil outlet of guide's pressure reducing valve (6), oil outlet and pilot valve
(8) it connects.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810096196.7A CN108179781A (en) | 2018-01-31 | 2018-01-31 | Loader hydraulic control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810096196.7A CN108179781A (en) | 2018-01-31 | 2018-01-31 | Loader hydraulic control system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108179781A true CN108179781A (en) | 2018-06-19 |
Family
ID=62551805
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810096196.7A Withdrawn CN108179781A (en) | 2018-01-31 | 2018-01-31 | Loader hydraulic control system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108179781A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110714957A (en) * | 2019-08-26 | 2020-01-21 | 宁波江北宇洲液压设备厂 | High-integration pilot multi-way valve bank and crane |
| CN111720369A (en) * | 2020-06-30 | 2020-09-29 | 潍柴动力股份有限公司 | Liquid filling system and engineering machinery |
| CN112334669A (en) * | 2019-03-28 | 2021-02-05 | 日立建机株式会社 | Construction machine |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3796336A (en) * | 1969-06-25 | 1974-03-12 | F Ratliff | Hydraulic system for a loader |
| CN201679783U (en) * | 2010-01-26 | 2010-12-22 | 徐工集团工程机械股份有限公司科技分公司 | Pilot oil supply system of loader |
| CN205975777U (en) * | 2016-08-31 | 2017-02-22 | 雷沃重工股份有限公司 | Loader hydraulic system |
| CN106836363A (en) * | 2016-12-30 | 2017-06-13 | 山东临工工程机械有限公司 | Loader hydraulic system |
| CN107268703A (en) * | 2017-07-06 | 2017-10-20 | 山东临工工程机械有限公司 | Loader hydraulic system |
| CN207905007U (en) * | 2018-01-31 | 2018-09-25 | 山东临工工程机械有限公司 | Loader hydraulic control system |
-
2018
- 2018-01-31 CN CN201810096196.7A patent/CN108179781A/en not_active Withdrawn
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3796336A (en) * | 1969-06-25 | 1974-03-12 | F Ratliff | Hydraulic system for a loader |
| CN201679783U (en) * | 2010-01-26 | 2010-12-22 | 徐工集团工程机械股份有限公司科技分公司 | Pilot oil supply system of loader |
| CN205975777U (en) * | 2016-08-31 | 2017-02-22 | 雷沃重工股份有限公司 | Loader hydraulic system |
| CN106836363A (en) * | 2016-12-30 | 2017-06-13 | 山东临工工程机械有限公司 | Loader hydraulic system |
| CN107268703A (en) * | 2017-07-06 | 2017-10-20 | 山东临工工程机械有限公司 | Loader hydraulic system |
| CN207905007U (en) * | 2018-01-31 | 2018-09-25 | 山东临工工程机械有限公司 | Loader hydraulic control system |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112334669A (en) * | 2019-03-28 | 2021-02-05 | 日立建机株式会社 | Construction machine |
| CN110714957A (en) * | 2019-08-26 | 2020-01-21 | 宁波江北宇洲液压设备厂 | High-integration pilot multi-way valve bank and crane |
| CN111720369A (en) * | 2020-06-30 | 2020-09-29 | 潍柴动力股份有限公司 | Liquid filling system and engineering machinery |
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| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WW01 | Invention patent application withdrawn after publication | ||
| WW01 | Invention patent application withdrawn after publication |
Application publication date: 20180619 |