CN106351898B - Land leveller front wheel driven hydraulic system - Google Patents
Land leveller front wheel driven hydraulic system Download PDFInfo
- Publication number
- CN106351898B CN106351898B CN201610920339.2A CN201610920339A CN106351898B CN 106351898 B CN106351898 B CN 106351898B CN 201610920339 A CN201610920339 A CN 201610920339A CN 106351898 B CN106351898 B CN 106351898B
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- China
- Prior art keywords
- valve
- mouthfuls
- hydraulic
- pilot operated
- operated directional
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- 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.)
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
-
- 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
- E02F3/76—Graders, bulldozers, or the like with scraper plates or ploughshare-like elements; Levelling scarifying devices
- E02F3/80—Component parts
- E02F3/84—Drives or control devices therefor, e.g. hydraulic drive systems
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/2053—Type of pump
- F15B2211/20546—Type of pump variable capacity
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mining & Mineral Resources (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Operation Control Of Excavators (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The present invention relates to land leveller front wheel driven hydraulic systems, and freely being distributed for the existing two front-wheel drive motor flow of land leveller of solution causes to be likely to occur unilateral slippage problems；A kind of land leveller front wheel driven hydraulic system is provided, the control valve connected including left hydraulic motor, right hydraulic motor, hydraulic pump with hydraulic pump, it is characterised in that further include distributing valve, distributing valve includes electromagnetic switch valve, pilot operated directional control valve, impartial distributing valve；The electromagnetic switch valve is connected between the hydraulic control end of the pilot operated directional control valve and T mouthfuls；Electromagnetic switch valve makes pilot operated directional control valve work in the first working position or the second working position, and hydraulic oil enters motor through pilot operated directional control valve, impartial distributing valve equalization or only freely distributed on demand to hydraulic motor through pilot operated directional control valve.
Description
Technical field
The present invention relates to a kind of level land machine hydraulic system, more specifically to a kind of land leveller front wheel driven hydraulic system
System.
Background technology
Front-wheel drive open type hydraulic system of the existing land leveller front-wheel drive mode for pump two motor of band, as shown in Figure 1,
1 pump discharge pressure oil of hydraulic pump is directly accessed two motors 3 in parallel after control valve 2, into the flow of the pressure oil of two motors
For free distribution, when a side drive wheel and ground attachment condition variation, i.e., the ground reaction force that the side drive wheel is subject to becomes
Small, then the side motor, which obtains the flow of pressure oil, to increase, and the side motor rotary speed is caused to be accelerated, and opposite side motor rotary speed is slack-off
Do not turn even, i.e. the unilateral slipping phenomenon of front-wheel.
Because land leveller working condition is more complicated, ground attachment condition is changeable, and unbalance loading operating mode is relatively more, it is easy to make
Into the phenomenon that wheel speed is inconsistent during land leveller straight line operation or so or even will appear above-mentioned unilateral skidding, causing complete machine every
Degradation if power loss increases, hauling ability is deteriorated, while skids and tire wear is caused to aggravate, causes ground to adhere to item
Part becomes worse, greatly reduces the economy and operating efficiency of land leveller.
Invention content
The technical problem to be solved by the present invention is to be directed to existing two front-wheel drive motor flow of land leveller and freely distribute to cause
Unilateral slippage problems are likely to occur, and a kind of land leveller front wheel driven hydraulic system is provided.
The present invention is such for the technical solution for realizing its purpose：It provides a kind of including left hydraulic motor, right hydraulic pressure horse
It reaches, hydraulic pump, control valve, it is characterised in that further include the control circuit that distributing valve is connected with distributing valve, the distributing valve has
Flow freely distributes and two kinds of flow output modes of impartial distribution, the pump of the work oil inlet and the hydraulic pump of the control valve
Mouth connection, B mouthfuls of the work of the control valve connect simultaneously with the first actuator port of the left hydraulic motor and right hydraulic motor；
A mouthfuls of the allocated valves of work of the control valve are connected with the second actuator port of the left hydraulic motor and right hydraulic motor.
In the present invention, hydraulic pressure, which has from the work oil inlet of the control valve, to be flowed into, from work A mouthful output, from work B mouthfuls flow back after again from
The fuel tank circuit interface of control valve enters fuel tank circuit；Or from B mouthfuls of outputs of work, again from control valve after A mouthfuls of reflux of work
Fuel tank circuit interface enters fuel tank circuit；Distributing valve can realize impartial distribution with freely distributing two kinds of assignment of traffic patterns.When
Land leveller control circuit control distributing valve in straight line operation works in impartial allocation model, and front-wheel both sides motor is made to be assigned to phase
Deng flow, the ground attachment condition regardless of front-wheel both sides tire can all make front-wheel both sides motors keep equal rotating speed,
Eliminate unilateral slipping phenomenon.When land leveller turns to, control circuit control distributing valve switches to free allocation model, front-wheel both sides
Motor is turned to and is smoothed out according to the automatic distribution flow of needs, guarantee is turned to.
In above-mentioned land leveller front wheel driven hydraulic system, the distributing valve has P mouthfuls, T mouthfuls, C mouthfuls, D mouthfuls；T mouthfuls and fuel tank
Circuit connects, and is connected with the P mouths of the distributing valve with A mouthfuls of the work of the control valve, the C mouths of the distributing valve are corresponding with D mouthfuls
It is connected with the left hydraulic motor and the second actuator port of right hydraulic motor.The distributing valve and including electromagnetic switch valve, hydraulic control
Reversal valve, impartial distributing valve, the electromagnetic switch valve are connected between the hydraulic control end of the pilot operated directional control valve and T mouthfuls, described equal
Distributing valves is waited to be made of two identical throttle valves, the K mouths company of one end of two throttle valves with the impartial distributing valve
Logical, the other end correspondence of one of throttle valve is connected with described C mouthfuls.The other end of another throttle valve is connected with D mouthfuls；It is described
Pilot operated directional control valve has with the P mouthful E connected mouths, with first hydraulic fluid port that connects of K mouthfuls of distributing valve of equalization and with described C mouthfuls and D
Second hydraulic fluid port of mouth connection；The hydraulic control end of the pilot operated directional control valve is connected with the E mouths of the pilot operated directional control valve, the liquid controlled reversing
It is connected when valve is in the first working position with the first hydraulic fluid port for its E mouthfuls, its E mouthfuls and the when the pilot operated directional control valve is in the second working position
Two hydraulic fluid ports are connected.
In above-mentioned land leveller front wheel driven hydraulic system, third throttle valve is connected between described C mouthfuls and D mouthful.
In above-mentioned land leveller front wheel driven hydraulic system, the hydraulic control end of the pilot operated directional control valve and the E mouths of pilot operated directional control valve
Between oil circuit be equipped with the 4th throttle valve.
In above-mentioned land leveller front wheel driven hydraulic system, control circuit is further included, the electromagnet of the electromagnetic switch valve connects
It is connected in institute's control circuit, the control circuit includes the pressure switch triggered by the land leveller steering pressure, pressure switch
The electromagnetic switch valve, which is on position, during closure makes the pilot operated directional control valve work in the second working position, when pressure switch disconnects
The electromagnetic switch valve, which is in cut-off position, makes the pilot operated directional control valve work in the first working position.
In above-mentioned land leveller front wheel driven hydraulic system, the control circuit further includes forerunner and enables switch, control relay
Device, the forerunner enables switch and the electromagnet of electromagnetic switch valve is connected on the output circuit of the control relay；It is described
Pressure switch is serially connected on the coil of the control relay.
In above-mentioned land leveller front wheel driven hydraulic system, distributing valve work light is further included, the distributing valve work refers to
Show the electromagnet of lamp and the electromagnetic switch valve in parallel or series.
Compared with prior art, the present invention the front-wheel drive that the present invention effectively solves the existing pump of land leveller one two motor of band is opened
The defects of straight trip present in formula hydraulic system unilateral skidding, land leveller are being kept straight on to during turning to and arrive straight trip again, are being distributed
Valve assignment of traffic pattern automatically switches, and realizes automatic control function.
Description of the drawings
Fig. 1 is existing land leveller front wheel driven hydraulic systematic schematic diagram.
Fig. 2 is land leveller front wheel driven hydraulic system of the present invention.
Fig. 3 is the schematic diagram of distributing valve in the present invention.
Fig. 4 is the electric control theory figure of the present invention.
Parts title and serial number in figure：
Hydraulic pump 1, control valve 2, motor 3, distributing valve 4, electromagnetic switch valve 41, pilot operated directional control valve 42, impartial distributing valve 43,
First throttle valve 431, second throttle 432, third throttle valve 44, the 4th throttle valve 45, pressure switch 5, forerunner enable switch
6th, relay 7, electromagnet 8, distributing valve work light 9 are controlled.
Specific embodiment
Illustrate specific embodiment below in conjunction with the accompanying drawings.
As shown in Fig. 2, the land leveller front wheel driven hydraulic system in the present embodiment includes motor 3, hydraulic pump 1, control valve
2nd, distributing valve 3 etc..Wherein hydraulic pump 1 is Variable plunger pump, and motor 3 includes two hydraulic motors with left and right front-wheel.Control valve 2
It is connect with hydraulic pump 1, the first work of the B mouths in actuator port, that is, A mouthfuls and B mouthfuls of two of control valve 2 and two hydraulic motors 3
Hydraulic fluid port connects, and A mouths of control valve 2 connect with the P mouths of distributing valve 4, the C mouths of distributing valve 4 and D mouthfuls of correspondences and two hydraulic motors 3
The second actuator port connection.By manipulating control valve 2, it can be achieved that the A mouths of control valve 2 flow direction different with B oral fluid pressure oils, from
And realize positive and negative rotation of motor.
As shown in figure 3, distributing valve 4 have P mouthfuls, T mouthfuls, C mouthfuls, D mouthfuls and including electromagnetic switch valve 41, pilot operated directional control valve 42,
Impartial distributing valve 43；Wherein：Pilot operated directional control valve 42 has E mouthfuls, the first hydraulic fluid port, that is, G mouthfuls, the second hydraulic fluid port, that is, F mouthfuls and H mouthfuls, wherein F
Mouthful connected with C mouthfuls, H mouthfuls connected with D mouthfuls, E mouthfuls connected with P mouthfuls.Electromagnetic switch valve 41 is connected to the hydraulic control end of pilot operated directional control valve 42,
The hydraulic control end of pilot operated directional control valve 42 connects simultaneously through the 4th throttle valve 45 with E mouthfuls, and the spring cavity of pilot operated directional control valve 42 connects with T mouthfuls
It is logical, T mouthfuls and fuel tank circuit communication.When pilot operated directional control valve 42 is in the first working position, E mouthfuls are connected with G mouthfuls, at pilot operated directional control valve 42
When the second working position, E mouthfuls are connected with F mouthfuls and H mouthfuls.
As shown in figure 3, impartial distributing valve 42 is made of two identical throttle valves, which is respectively first segment
Wherein one end of stream valve 431 and second throttle 432, first throttle valve 431 and second throttle 432 is distributed after being connected with equalization
The K mouths connection of valve, the other end port of first throttle valve 431 are connected with C mouthfuls, and the another port of second throttle 432 connects with D mouthfuls
It is logical.Third throttle valve 44 is connected between C mouthfuls and D mouthfuls.The K mouths of impartial distributing valve are connected with the G mouths of pilot operated directional control valve.
As shown in Fig. 2 Fig. 4, control circuit includes forerunner and enables switch 6, control relay 7, pressure switch 5, distributing valve work
Make indicator light 9.Increase pressure sensor at steering gear feedback port, pressure switch 5 is triggered by land leveller steering pressure, works as level land
When machine is kept straight on, pressure sensor no signal, pressure switch 5 is off-state；When land leveller turns to, pressure sensor has letter
Number, triggering pressure switch 5 is at closed state.Forerunner enables switch 6 and the electromagnet 8 of electromagnetic switch valve 41 is connected on control
On outputting circuit for relay processed, i.e., the contact series with controlling relay；Pressure switch 5 is serially connected in the coil of control relay
On.Distributing valve work light 9 is in parallel with the electromagnet 8 of electromagnetic switch valve.The K1 termination power anodes of control circuit, K2 terminations
Power cathode.
In the present embodiment, when forerunner's function, which enables switch 6, to be disconnected, i.e., when vehicle does not use front-wheel drive, distributing valve
Work light 9 does not work, and electromagnet 8 must not be electric, and the assignment of traffic pattern of distributing valve 4 is free allocation model.
When forerunner's function, which enables switch 6, to be closed, distributing valve work light 9 is bright, meanwhile, electromagnet 8 obtains electric, Ye Ji electricity
The electromagnetic coil of magnetic switch valve 41 obtain it is electric, electromagnetic switch valve be in by state, pilot operated directional control valve works in the first working position,
I.e. upper, the E mouths of pilot operated directional control valve and G mouthfuls of conductings at this time, E mouthfuls with F mouthfuls and H mouthfuls by front wheel driven hydraulic oil is through equalization
Distributing valve is equally distributed on two hydraulic motors from C mouthfuls and D mouthfuls outputs, ensures front-wheel both sides motor during land leveller straight trip
Rotating speed is equal.At this point, when land leveller turns to, pressure switch 5 is closed, and control relay 7 obtains electric, distributing valve work light 9
Go out, meanwhile, 8 dead electricity of electromagnet namely electromagnetic switch valve are on position, pilot operated directional control valve work in the second working position namely
Bottom, E mouths and F mouthfuls and H mouthfuls of pilot operated directional control valve are both turned on, and front wheel driven hydraulic oil is freely distributed to C mouthfuls and D mouthfuls outputs, is protected
Card land leveller steering is smoothed out；When land leveller restores to keep straight on, pressure switch 5 disconnects, and controls 7 dead electricity of relay, distributing valve
Work light 9 is bright, meanwhile, electromagnet 8 must be electric, and pilot operated directional control valve works with upper again, and the assignment of traffic pattern of distributing valve 4 is certainly
It is dynamic to be switched to impartial allocation model.
Claims (5)
1. a kind of land leveller front wheel driven hydraulic system, special including left hydraulic motor, right hydraulic motor, hydraulic pump, control valve
Sign is the control circuit for further including distributing valve and being connect with distributing valve, and there is the distributing valve flow freely to distribute and equal decile
With two kinds of flow output modes, the work oil inlet of the control valve is connect with the pumping hole of the hydraulic pump, the control valve
B mouthfuls of work connects simultaneously with the first actuator port of the left hydraulic motor and right hydraulic motor；A mouthfuls of the work of the control valve
The allocated valve is connected with the second actuator port of the left hydraulic motor and right hydraulic motor；
The distributing valve has P mouthfuls, T mouthfuls, C mouthfuls, D mouthfuls；T mouthfuls connect with fuel tank circuit, P mouths and the control of the distributing valve
A mouthfuls of connections of work of valve, the C mouths of the distributing valve are connected with the second actuator port of the left hydraulic motor, the distributing valve
D mouths connected with right second actuator port of hydraulic motor；
The distributing valve includes electromagnetic switch valve, pilot operated directional control valve, impartial distributing valve, and the electromagnetic switch valve is connected to the liquid
It controls between the hydraulic control end of reversal valve and T mouthfuls, the equalization distributing valve is made of two identical throttle valves, two throttle valves
K mouth of the one end with the impartial distributing valve connect, the other end of one of throttle valve is connected with described C mouthfuls, another
The other end of throttle valve is connected with D mouthfuls；The pilot operated directional control valve has and the P mouthfuls of E connected mouths and impartial K mouthfuls of the distributing valve
Connection the first hydraulic fluid port and with C mouthfuls and D mouthful of second hydraulic fluid port connected；The hydraulic control end of the pilot operated directional control valve and the hydraulic control
The E mouths connection of reversal valve, is connected for its E mouthfuls, the hydraulic control is changed when the pilot operated directional control valve is in the first working position with the first hydraulic fluid port
It is connected when being in the second working position to valve with the second hydraulic fluid port for its E mouthfuls；The electromagnet of the electromagnetic switch valve is connected to the control
On circuit, the control circuit includes the pressure switch triggered by the land leveller steering pressure, described in when pressure switch is closed
Electromagnetic switch valve, which is on position, makes the pilot operated directional control valve work in the second working position, and the electromagnetism is opened when pressure switch disconnects
Close valve makes the pilot operated directional control valve work in the first working position in cut-off position.
2. land leveller front wheel driven hydraulic system according to claim 1, it is characterised in that connect between described C mouthfuls and D mouthful
It is connected to third throttle valve.
3. land leveller front wheel driven hydraulic system according to claim 1, it is characterised in that the liquid of the pilot operated directional control valve
The oil circuit controlled between end and the E mouths of pilot operated directional control valve is equipped with the 4th throttle valve.
4. land leveller front wheel driven hydraulic system according to claim 1, it is characterised in that the control circuit further includes
Forerunner enables switch, control relay, the forerunner enable switch and electromagnetic switch valve electromagnet be connected on the control after
On the output circuit of electric appliance；The pressure switch is serially connected on the coil of the control relay.
5. land leveller front wheel driven hydraulic system according to claim 1, it is characterised in that further include distributing valve work and refer to
Show lamp, the electromagnet of the distributing valve work light and the electromagnetic switch valve is in parallel or series.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610920339.2A CN106351898B (en) | 2016-10-21 | 2016-10-21 | Land leveller front wheel driven hydraulic system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610920339.2A CN106351898B (en) | 2016-10-21 | 2016-10-21 | Land leveller front wheel driven hydraulic system |
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| Publication Number | Publication Date |
|---|---|
| CN106351898A CN106351898A (en) | 2017-01-25 |
| CN106351898B true CN106351898B (en) | 2018-06-26 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610920339.2A Active CN106351898B (en) | 2016-10-21 | 2016-10-21 | Land leveller front wheel driven hydraulic system |
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| Country | Link |
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| CN (1) | CN106351898B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107448425A (en) * | 2017-07-21 | 2017-12-08 | 广西柳工机械股份有限公司 | Control valve and land leveller front wheel driven hydraulic system |
| CN109356895A (en) * | 2018-10-31 | 2019-02-19 | 广西柳工机械股份有限公司 | Land leveller front-wheel drive control system |
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| CN106351898A (en) | 2017-01-25 |
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