CN108505579A - Excavate Electrical Control open type throttling hydraulic system - Google Patents
Excavate Electrical Control open type throttling hydraulic system Download PDFInfo
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- CN108505579A CN108505579A CN201810379342.7A CN201810379342A CN108505579A CN 108505579 A CN108505579 A CN 108505579A CN 201810379342 A CN201810379342 A CN 201810379342A CN 108505579 A CN108505579 A CN 108505579A
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- Prior art keywords
- valve
- hydraulic system
- open type
- block assembly
- electrical control
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- 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
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Operation Control Of Excavators (AREA)
Abstract
The invention discloses a kind of excavation Electrical Control open type throttling hydraulic systems, belong to technical field of engineering machinery.It solves the defect that labor intensity existing for conventional excavators hydraulic system in the prior art is high, risks and assumptions are big, after-sales service is inconvenient.Its agent structure includes main control valve, main pump and executive component, the executive component is connect with main control valve and main pump respectively, the excavation Electrical Control open type throttling hydraulic system includes solenoid valve block assembly, switch electromagnetic valve valve block assembly and pressure reducing valve, the solenoid valve block assembly is connect with main control valve and switch electromagnetic valve valve block assembly respectively, and the pressure reducing valve is connect with switch electromagnetic valve valve block assembly and main pump respectively.Present invention is mainly used on excavator.
Description
Technical field：
The invention belongs to technical field of engineering machinery, specifically, more particularly to a kind of excavation Electrical Control open type throttling liquid
Pressure system.
Background technology：
Excavator, also known as excavating machinery are to be excavated to be higher or lower than the material for holding machine side with scraper bowl, and be packed into haulage vehicle
Or unload to the earthmoving machinery of windrow factory, from the point of view of the development of engineering machinery in recent years, the development of excavator is relatively fast, excavator
Have become one of most important engineering machinery in engineering construction.In medium-and-large-sized excavator, based on positive flow or minus flow；
Mini-excavator, based on load-sensitive and throttle system.
In throttle system, the discharge capacity of pump relies primarily on the negative-feedback of itself, that is, the outlet pressure pumped acts on the discharge capacity of pump
On regulating mechanism, pressure is higher, and discharge capacity is lower, and pressure is lower, and discharge capacity is higher, to achieve the effect that match engine power；It opens
Formula throttle system has passed through the improvement of long market verification and system performance, and market has been obtained with its preferable energy consumption efficiency performance
It is widely recognized as.It is intelligent, energy saving, comfortable, reliable, it is always the development trend of excavator hydraulic system；With China in recent years
The continuous development of capital construction, it is intelligent, further development will be obtained.
Invention content：
In order to solve labor intensity height, risks and assumptions existing for conventional excavators hydraulic system in the prior art greatly, after sale
Safeguard inconvenient disadvantage, the present invention provides a kind of excavation Electrical Control open type throttling hydraulic system being different from the prior art,
Labor intensity is reduced, it is more intelligent, main control valve R＆D cycle and R＆D costs are reduced, risks and assumptions is reduced and takes after sale
Business is more convenient.
To achieve the goals above, realization that the present invention adopts the following technical solutions：
A kind of excavation Electrical Control open type throttling hydraulic system, including main control valve, main pump and executive component, the executive component
It is connect respectively with main control valve and main pump, the excavation Electrical Control open type throttling hydraulic system includes solenoid valve block assembly, switch electricity
Magnet valve valve block assembly and pressure reducing valve, the solenoid valve block assembly are connect with main control valve and switch electromagnetic valve valve block assembly respectively, institute
Pressure reducing valve is stated to connect with switch electromagnetic valve valve block assembly and main pump respectively.
Further, the executive component includes rotary motor, bucket arm cylinder, dozer oil cylinder, running motor, is crushed
Hammer, boom cylinder and bucket cylinder, the main control valve respectively with rotary motor, bucket arm cylinder, dozer oil cylinder, running motor,
Quartering hammer, boom cylinder are connected with bucket cylinder.
Further, the excavation Electrical Control open type throttling hydraulic system includes accumulator one-way valve block, the accumulator
The oil inlet of one-way valve block is connect with pressure reducing valve, and oil outlet is connect with switch electromagnetic valve valve block assembly.
Further, the excavation Electrical Control open type throttling hydraulic system further includes control unit ECU, described control unit
ECU is connect with left operation handle, right operation handle, left threading valve and right threading valve respectively, and control unit ECU also passes through electric signal
It is connect with solenoid valve block assembly.
Further, the switch electromagnetic valve valve block assembly includes switch electromagnetic valve VA1 and switch electromagnetic valve VA2, described
Switch electromagnetic valve VA1 is connected in parallel with switch electromagnetic valve VA2 and is connect afterwards with the oil outlet of accumulator one-way valve block.
Further, the main pump includes plunger pump P1, plunger pump P2 and gear pump P3.
Further, the main control valve is chip throttling main control valve.
Further, the left operation handle and right operation handle are electric control handle.
Compared with prior art, the beneficial effects of the invention are as follows：
1, labor intensity is reduced：Electric hand handle steering force is greatly reduced compared with pilot handle, effectively reduces labor intensity；
2, intelligent：The application of a whole set of solenoid valve in solenoid valve block assembly so that the output of complete machine hydraulic system is faster, more
It is accurate；
3, risks and assumptions are reduced：In conventional hydraulic, to realize straight line moving function, signal oil duct, signal are needed
Oil duct diameter is small, is connected by each aperture, this is machined with very high requirement to signal oil duct, once signal oil duct
Concentricity is bad, then can influence overall performance, in the present invention, can cancel signal oil road, eliminate associated risk factor；
4, facilitate after market service：The invention enables complete machine hydraulic systems to be further simplified, if after sale when something goes wrong,
Attendant needs the factor investigated to reduce, therefore after market service is more convenient.
Description of the drawings：
Fig. 1 is the principle of the present invention figure；
Fig. 2 is the partial enlarged view at K in the present invention；
Fig. 3 is the partial enlarged view at G in the present invention；
Fig. 4 is the schematic diagram of main control valve in the present invention；
Fig. 5 is the structural schematic diagram of solenoid valve block assembly in the present invention；
Fig. 6 is the structural schematic diagram of main control valve revolution connection in the present invention；
Fig. 7 is the logical relation schematic diagram between output pressure, handle angle in the present invention.
In figure：1, main control valve；2, switch electromagnetic valve valve block assembly；3, main pump；4, rotary motor；5, bucket arm cylinder；6, it pushes away
Mamoty oil cylinder；7, running motor；9, quartering hammer；10, boom cylinder；11, bucket cylinder；12, solenoid valve block assembly；13, left behaviour
Make handle；14, right operation handle；15, left threading valve；16, right threading valve；17, control unit ECU；18, pressure reducing valve；19, accumulation of energy
Device one-way valve block；20, back oil road；21, oil input channel；22, valve body.
Specific implementation mode：
Below by specific embodiment and in conjunction with attached drawing, the invention will be further described.
Embodiment 1：
As shown in Figure 1, a kind of excavation Electrical Control open type throttling hydraulic system, including main control valve 1, main pump 3 and executive component,
The executive component is connect with main control valve 1 and main pump 3 respectively, and the excavation Electrical Control open type throttling hydraulic system includes solenoid valve
Block assembly 12, switch electromagnetic valve valve block assembly 2 and pressure reducing valve 18, the solenoid valve block assembly 12 respectively with main control valve 1 and switch
Solenoid valve valve block assembly 2 connects, and the pressure reducing valve 18 is connect with switch electromagnetic valve valve block assembly 2 and main pump 3 respectively.
Embodiment 2：
A kind of excavation Electrical Control open type throttling hydraulic system, including accumulator one-way valve block 19, the accumulator check valve
The oil inlet of block 19 is connect with pressure reducing valve 18, and oil outlet is connect with switch electromagnetic valve valve block assembly 2；The executive component includes back
Turn motor 4, bucket arm cylinder 5, dozer oil cylinder 6, running motor 7, quartering hammer 9, boom cylinder 10 and bucket cylinder 11, the master
Control valve 1 respectively with rotary motor 4, bucket arm cylinder 5, dozer oil cylinder 6, running motor 7, quartering hammer 9, boom cylinder 10 and scraper bowl
Oil cylinder 11 connects；The excavation Electrical Control open type throttling hydraulic system further includes control unit ECU17, described control unit
ECU17 is connect with left operation handle 13, right operation handle 14, left threading valve 15 and right threading valve 16 respectively, control unit ECU17
Also it is connect with solenoid valve block assembly 12 by electric signal；The switch electromagnetic valve valve block assembly 2 includes switch electromagnetic valve VA1 and opens
Powered-down magnet valve VA2, the switch electromagnetic valve VA1 and switch electromagnetic valve VA2 are connected in parallel to be gone out with accumulator one-way valve block 19 afterwards
Hydraulic fluid port connects；The main pump 3 includes plunger pump P1, plunger pump P2 and gear pump P3；The main control valve 1 is chip throttling master control
Valve；The left operation handle 13 and right operation handle 14 are electric control handle.Other parts are same as Example 1.
The main pump 3 includes plunger pump P1, plunger pump P2 and gear pump P3, corresponds to three hydraulic fluid ports, respectively hydraulic fluid port respectively
A1, hydraulic fluid port A2 and hydraulic fluid port A3, hydraulic fluid port A1 and hydraulic fluid port A2 are the oil outlets of two linkages, i.e. the discharge capacity of two oil outlets is forever equal,
The discharge capacity of plunger pump P1 and plunger pump P2 are adjustable, and oil outlet pressure is bigger, and discharge capacity is smaller, conversely, pressure is smaller, flow is bigger,
To match the power of engine；The discharge capacity of gear pump P3 is non-adjustable.
Main control valve 1 is chip throttling main control valve, i.e. main control valve 1 is bolted by multi-piece valve bodies, and both sides are removed
Outside end cap, as shown in figure 4, each is from left to right revolution connection, dozer connection, P3 oil inlets connection, dipper one, swing arm two successively
Connection, left lateral walk connection, P1, P2 oil inlet connection, right lateral and walk connection, swing arm one, dipper bigeminy and scraper bowl connection.Executive component includes revolution horse
Up to 4, bucket arm cylinder 5, dozer oil cylinder 6, running motor 7, quartering hammer 9, boom cylinder 10 and bucket cylinder 11, auxiliary includes pipe
Road, connector etc..
As shown in Fig. 2, mono- tunnels hydraulic fluid port A3 of gear pump P3 are connected on main control valve 1, pressure reducing valve 18 is connect all the way, and pressure reducing valve 18 will
The outlet pressure of gear pump P3 is reduced to 4MPa, the oil outlet connecting valve solenoid valve valve block assembly 2 of pressure reducing valve 18, switch electromagnetic valve
Valve block assembly 2 is equipped with switch electromagnetic valve VA1 and switch electromagnetic valve VA2, and switch electromagnetic valve VA1 is switch electromagnetic valve valve block assembly
2 pressure shut-off valve is powered, then the oil inlet of solenoid valve block assembly 12 connects high pressure guide oil, power-off, then solenoid valve block assembly 12
Oil inlet take back oil.
The present invention is depressurized by main pump 3 and is obtained without individual pioneer pump, pilot pressure；The hydraulic fluid port A3 of main pump 3 is through pressure reducing valve
18 with after accumulator one-way valve block 19, and the pressure of hydraulic fluid port A3 is reduced to a basicly stable value, is for pilot pressure；Pilot pressure is being opened
It is divided into two-way on powered-down magnet valve valve block assembly 2, passes through switch electromagnetic valve VA2, the high low speed of control walking all the way；Switch electromagnetic valve
VA1 provides pressure oil for solenoid valve block assembly 12.
As shown in figure 3, solenoid valve block assembly 12 is the integrated solenoid valve block individually arranged, it is installed above to have
VB1~VB8, VC1~VC8 totally 16 solenoid valves；VB6 is switch electromagnetic valve, remaining is proportion magnetic valve.Solenoid valve block assembly 12
It is upper there are one or Pp mouthful multiple, T mouthfuls of one or more, and correspond to the C mouths of correlation main valve stem.As shown in figure 5, electromagnetism valve block is total
At having two class oil ducts inside 12, first, back oil road 20, is connected with T mouthfuls, the fluid of the inside is low pressure fluid；Second is that oil input channel 21,
It is connected with Pp mouthfuls, the fluid of the inside is high-voltage oil liquid, and Pp pressure oils are provided by switch electromagnetic valve VA1.Solenoid valve (VB1~VB8 or
Any one in VC1~VC8) C mouthfuls of outlet be connected with the pilot port of the valve rod of main control valve 1, it is high when fluid is high pressure oil
Pressure oil directly acts on valve rod end face, and hydraulic coupling overcomes the spring force on valve rod, pushes valve rod action, corresponding dynamic to realize
Make.
The transposition that P3 oil inlets join in switch electromagnetic valve VB6 control main control valves 1, when left and right walking while acting, and swing arm
Oil cylinder 10, bucket arm cylinder 5 or 11 thrin of bucket cylinder or multiple actions are simultaneously when acting, switch electromagnetic valve VB6 energizations,
The oil outlet output of switch electromagnetic valve VB6 is no more than the high pressure of Pp pressure, P3 oil inlets connection transposition, realization excavator straight line moving work(
Can, i.e., the running motor 7 of left and right side obtains same traffic input.Remaining 15 proportion magnetic valve controls corresponding valve respectively
Bar, to the corresponding action of control.
Wish is passed to handle by operator when work, and handle receives the angle that operator gives, and passes through voltage, electric current etc.
Signal passes to control unit ECU17, and control unit ECU17 handles the signal received, the output phase induced current, ratio
Solenoid valve (VB1~VB5, VB7~VB8, VC1~VC8) according to obtain different size of electric current input, C mouthfuls it is exportable not
Relationship more than different pressure output Px, the Px and handle angle a of Pp pressure as shown in fig. 7, be to operate excavator revolution
Example, operator will allow excavator to carry out left revolution action, and operation handle gives handle certain angle input, this input is final
The proportion magnetic valve VB8 of the left revolution of control is set to be powered, C mouthfuls of the delivery outlet of proportion magnetic valve VB8 exports certain guide oil with pressure
Liquid as shown in fig. 6, guide's fluid with pressure acts on the xAs mouths on the revolution connection on main control valve 1, and pushes revolution connection spool left
It moves, the As mouth output pressures of valve body 22, rotary motor 4 is made to act, excavator turns left；After handle resets, proportion magnetic valve VB8's
Input current is zero, and the output pressure of C mouthfuls of the delivery outlet of proportion magnetic valve VB8 is zero, and the xAs mouth pressure on revolution connection valve is
Zero, the As mouth pressure outputs of position during valve rod restores, valve body 22 are interrupted, and excavator stops turning left.Other action process are the same as above-mentioned.
As shown in fig. 7, being a kind of controlling curve of proportion magnetic valve (such as VB1), abscissa is with the angle of handle or foot valve
It is input to spend a, and ordinate indicates the output pilot pressure Px of proportion magnetic valve, for example, proportional solenoid valve control bucket cylinder 11
Big chamber oil inlet, handle is failure to actuate, proportion magnetic valve no power, and the pilot pressure of proportion magnetic valve output is zero, and valve rod is motionless
Make, therefore the big chamber of bucket cylinder 11 also attonity；Handle acts, and control unit ECU17 starts to capture the intermediate conversion of handle
Signal (such as voltage U or resistance R), then by processing, it is more than sky to give proportion magnetic valve input current signal I, handle angle a
After stroke a1, under current signal I effects, proportion magnetic valve starts output pressure Px1, and handle angle continues to increase, and reaches a2
Afterwards, proportion magnetic valve is opened completely, and output pressure reaches maximum value Px2, under the action of pressure Px, the scraper bowl of bucket cylinder 11
Valve rod acts, and to the big chamber fuel feeding of bucket cylinder 11, scraper bowl starts to act main control valve 1.
Wherein a1 indicates the idle stroke of handle or foot valve, and the handle is left operation handle 13 or right operation handle 14,
Foot valve is left threading valve 15 or right threading valve 16.
Claims (8)
1. a kind of excavation Electrical Control open type throttling hydraulic system, including main control valve (1), main pump (3) and executive component, the execution
Element is connect with main control valve (1) and main pump (3) respectively, it is characterised in that：The excavation Electrical Control open type throttling hydraulic system packet
Solenoid valve block assembly (12), switch electromagnetic valve valve block assembly (2) and pressure reducing valve (18) are included, the solenoid valve block assembly (12) is respectively
Connect with main control valve (1) and switch electromagnetic valve valve block assembly (2), the pressure reducing valve (18) respectively with switch electromagnetic valve valve block assembly
(2) it is connected with main pump (3).
2. excavation Electrical Control open type throttling hydraulic system according to claim 1, it is characterised in that：The executive component packet
Include rotary motor (4), bucket arm cylinder (5), dozer oil cylinder (6), running motor (7), quartering hammer (9), boom cylinder (10) and
Bucket cylinder (11), the main control valve (1) respectively with rotary motor (4), bucket arm cylinder (5), dozer oil cylinder (6), walking horse
It is connected up to (7), quartering hammer (9), boom cylinder (10) and bucket cylinder (11).
3. excavation Electrical Control open type throttling hydraulic system according to claim 2, it is characterised in that：The excavation Electrical Control
Open type throttling hydraulic system includes accumulator one-way valve block (19), the oil inlet and pressure reducing valve of the accumulator one-way valve block (19)
(18) it connects, oil outlet is connect with switch electromagnetic valve valve block assembly (2).
4. excavation Electrical Control open type throttling hydraulic system according to claim 3, it is characterised in that：The excavation Electrical Control
Open type throttling hydraulic system further includes (17) control unit ECU, described control unit ECU (17) respectively with left operation handle
(13), right operation handle (14), left threading valve (15) and right threading valve (16) connection, control unit ECU (17) also pass through telecommunications
It number is connect with solenoid valve block assembly (12).
5. excavation Electrical Control open type throttling hydraulic system according to claim 4, it is characterised in that：The switch electromagnetic valve
Valve block assembly (2) includes switch electromagnetic valve VA1 and switch electromagnetic valve VA2, the switch electromagnetic valve VA1 and switch electromagnetic valve VA2
It is connect with the oil outlet of accumulator one-way valve block (19) after being connected in parallel.
6. excavation Electrical Control open type throttling hydraulic system according to claim 5, it is characterised in that：Main pump (3) packet
Include plunger pump P1, plunger pump P2 and gear pump P3.
7. excavation Electrical Control open type throttling hydraulic system according to claim 6, it is characterised in that：The main control valve (1)
For chip throttling main control valve.
8. excavation Electrical Control open type throttling hydraulic system according to claim 7, it is characterised in that：The left operation handle
(13) and right operation handle (14) is electric control handle.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810379342.7A CN108505579B (en) | 2018-04-25 | 2018-04-25 | Electric control open type throttling hydraulic system of excavator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810379342.7A CN108505579B (en) | 2018-04-25 | 2018-04-25 | Electric control open type throttling hydraulic system of excavator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108505579A true CN108505579A (en) | 2018-09-07 |
| CN108505579B CN108505579B (en) | 2023-08-18 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810379342.7A Active CN108505579B (en) | 2018-04-25 | 2018-04-25 | Electric control open type throttling hydraulic system of excavator |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW567288B (en) * | 2003-01-23 | 2003-12-21 | Taiwan Semiconductor Mfg | Throttle valve having multi-servo regions |
| JP2009167618A (en) * | 2008-01-11 | 2009-07-30 | Caterpillar Japan Ltd | Hydraulic circuit of hydraulic excavator |
| CN102086939A (en) * | 2009-12-07 | 2011-06-08 | 鸿富锦精密工业（深圳）有限公司 | Vane type throttle valve |
| CN106661858A (en) * | 2015-03-25 | 2017-05-10 | 株式会社小松制作所 | Wheel loader |
| CN107190799A (en) * | 2017-07-19 | 2017-09-22 | 徐州徐工挖掘机械有限公司 | A kind of many equipment flow limit systems of hydraulic crawler excavator and method |
| CN208219743U (en) * | 2018-04-25 | 2018-12-11 | 山东临工工程机械有限公司 | Excavate Electrical Control open type throttling hydraulic system |
-
2018
- 2018-04-25 CN CN201810379342.7A patent/CN108505579B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW567288B (en) * | 2003-01-23 | 2003-12-21 | Taiwan Semiconductor Mfg | Throttle valve having multi-servo regions |
| JP2009167618A (en) * | 2008-01-11 | 2009-07-30 | Caterpillar Japan Ltd | Hydraulic circuit of hydraulic excavator |
| CN102086939A (en) * | 2009-12-07 | 2011-06-08 | 鸿富锦精密工业（深圳）有限公司 | Vane type throttle valve |
| CN106661858A (en) * | 2015-03-25 | 2017-05-10 | 株式会社小松制作所 | Wheel loader |
| CN107190799A (en) * | 2017-07-19 | 2017-09-22 | 徐州徐工挖掘机械有限公司 | A kind of many equipment flow limit systems of hydraulic crawler excavator and method |
| CN208219743U (en) * | 2018-04-25 | 2018-12-11 | 山东临工工程机械有限公司 | Excavate Electrical Control open type throttling hydraulic system |
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| Publication number | Publication date |
|---|---|
| CN108505579B (en) | 2023-08-18 |
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