CN108505579B - Electric control open type throttling hydraulic system of excavator - Google Patents
Electric control open type throttling hydraulic system of excavator Download PDFInfo
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- CN108505579B CN108505579B CN201810379342.7A CN201810379342A CN108505579B CN 108505579 B CN108505579 B CN 108505579B CN 201810379342 A CN201810379342 A CN 201810379342A CN 108505579 B CN108505579 B CN 108505579B
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- excavator
- hydraulic system
- electromagnetic valve
- valve
- valve block
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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
Abstract
The invention discloses an electric control open type throttling hydraulic system of an excavator, and belongs to the technical field of engineering machinery. The hydraulic system of the excavator overcomes the defects of high labor intensity, large risk factors and inconvenient after-sales maintenance of the traditional hydraulic system of the excavator in the prior art. The main structure of the excavator electric control open type throttling hydraulic system comprises a main control valve, a main pump and an executing element, wherein the executing element is connected with the main control valve and the main pump respectively, the excavator electric control open type throttling hydraulic system comprises an electromagnetic valve block assembly, an on-off electromagnetic valve block assembly and a pressure reducing valve, the electromagnetic valve block assembly is connected with the main control valve and the on-off electromagnetic valve block assembly respectively, and the pressure reducing valve is connected with the on-off electromagnetic valve block assembly and the main pump respectively. The invention is mainly used for the excavator.
Description
Technical field:
the invention belongs to the technical field of engineering machinery, and particularly relates to an electric control open type throttling hydraulic system of an excavator.
The background technology is as follows:
an excavator, also called an excavating machine, is an earth moving machine that excavates a material higher or lower than a carrying surface with a bucket and loads the material into a transport vehicle or unloads the material into a stacker, and in recent years, the development of the excavator is relatively fast, and the excavator has become one of the most important engineering machines in engineering construction. In a medium-large excavator, positive flow or negative flow is mainly used; mini-excavators are mainly load sensitive and throttle systems.
In the throttle system, the discharge capacity of the pump mainly depends on negative feedback of the pump, namely, the outlet pressure of the pump acts on a discharge capacity adjusting mechanism of the pump, and the higher the pressure is, the lower the discharge capacity is, the lower the pressure is, and the higher the discharge capacity is, so that the effect of matching the power of the engine is achieved; open throttle systems have been widely accepted in the marketplace for better energy consumption efficiency performance through long term market verification and improvement of system characteristics. The intelligent, energy-saving, comfortable and reliable hydraulic system of the excavator is a development trend all the time; along with the continuous development of the capital construction of China in recent years, the intelligent development is necessary to obtain further development.
The invention comprises the following steps:
in order to solve the defects of high labor intensity, large risk factor and inconvenient after-sales maintenance of the traditional excavator hydraulic system in the prior art, the invention provides an electric control open throttle hydraulic system of an excavator, which is different from the prior art, and has the advantages of reducing the labor intensity, being more intelligent, reducing the research and development period and research and development cost of a main control valve, reducing the risk factor and being more convenient for after-sales service.
In order to achieve the above purpose, the present invention is realized by adopting the following technical scheme:
the utility model provides an electronic control open throttle hydraulic system of excavator, includes master control valve, main pump and executive component, executive component is connected with master control valve and main pump respectively, the electronic control open throttle hydraulic system of excavator includes solenoid valve piece assembly, switch solenoid valve piece assembly and relief pressure valve, solenoid valve piece assembly is connected with master control valve and switch solenoid valve piece assembly respectively, the relief pressure valve is connected with switch solenoid valve piece assembly and main pump respectively.
Further, the actuating element comprises a rotary motor, a bucket rod oil cylinder, a bulldozer oil cylinder, a walking motor, a breaking hammer, a movable arm oil cylinder and a bucket oil cylinder, and the main control valve is respectively connected with the rotary motor, the bucket rod oil cylinder, the bulldozer oil cylinder, the walking motor, the breaking hammer, the movable arm oil cylinder and the bucket oil cylinder.
Further, the electric control open type throttling hydraulic system of the excavator comprises an energy accumulator one-way valve block, an oil inlet of the energy accumulator one-way valve block is connected with a pressure reducing valve, and an oil outlet of the energy accumulator one-way valve block is connected with a switch electromagnetic valve block assembly.
Further, the electric control open throttle hydraulic system of the excavator further comprises a control unit ECU, wherein the control unit ECU is respectively connected with the left operating handle, the right operating handle, the left foot valve and the right foot valve, and the control unit ECU is further connected with the electromagnetic valve block assembly through electric signals.
Further, the on-off electromagnetic valve block assembly comprises an on-off electromagnetic valve VA1 and an on-off electromagnetic valve VA2, and the on-off electromagnetic valve VA1 is connected with the on-off electromagnetic valve VA2 in parallel and then is connected with an oil outlet of the one-way valve block of the energy accumulator.
Further, the main pump includes a plunger pump P1, a plunger pump P2, and a gear pump P3.
Further, the main control valve is a sheet type throttling main control valve.
Further, the left operating handle and the right operating handle are both electric control handles.
Compared with the prior art, the invention has the beneficial effects that:
1. the labor intensity is reduced: compared with a pilot handle, the electric handle operating force is greatly reduced, and the labor intensity is effectively reduced;
2. intelligent: the whole set of electromagnetic valves in the electromagnetic valve block assembly are applied, so that the output of the hydraulic system of the whole machine is faster and more accurate;
3. reducing risk factors: in the traditional hydraulic system, if the linear walking function is required, the signal oil duct is small in diameter and is connected through small holes of all the pieces, so that the processing of the signal oil duct has very high requirements, and once the concentricity of the signal oil duct is poor, the performance of the whole machine is affected;
4. convenient after-market service: the invention further simplifies the hydraulic system of the whole machine, and if after-sale problems occur, the factors to be checked by service personnel are reduced, so that after-sale market service is more convenient.
Description of the drawings:
FIG. 1 is a schematic diagram of the present invention;
FIG. 2 is an enlarged view of a portion at K in the present invention;
FIG. 3 is a partial enlarged view of the invention at G;
FIG. 4 is a schematic diagram of a master control valve according to the present invention;
FIG. 5 is a schematic diagram of a solenoid valve block assembly according to the present invention;
FIG. 6 is a schematic diagram of a master control valve swing joint structure in the present invention;
FIG. 7 is a schematic diagram of the logical relationship between output pressure and handle angle in the present invention.
In the figure: 1. a main control valve; 2. switching the electromagnetic valve block assembly; 3. a main pump; 4. a rotary motor; 5. a bucket rod oil cylinder; 6. a dozer blade cylinder; 7. a walking motor; 9. a breaking hammer; 10. a boom cylinder; 11. a bucket cylinder; 12. a solenoid valve block assembly; 13. a left operating handle; 14. a right operating handle; 15. a left foot valve; 16. a right foot valve; 17. a control unit ECU; 18. a pressure reducing valve; 19. an accumulator check valve block; 20. an oil return passage; 21. an oil inlet duct; 22. and a valve body.
The specific embodiment is as follows:
the invention will now be further illustrated by means of specific examples in connection with the accompanying drawings.
Example 1:
as shown in fig. 1, the electric control open-type throttling hydraulic system of the excavator comprises a main control valve 1, a main pump 3 and an executing element, wherein the executing element is respectively connected with the main control valve 1 and the main pump 3, the electric control open-type throttling hydraulic system of the excavator comprises an electromagnetic valve block assembly 12, an on-off electromagnetic valve block assembly 2 and a pressure reducing valve 18, the electromagnetic valve block assembly 12 is respectively connected with the main control valve 1 and the on-off electromagnetic valve block assembly 2, and the pressure reducing valve 18 is respectively connected with the on-off electromagnetic valve block assembly 2 and the main pump 3.
Example 2:
the electric control open type throttling hydraulic system of the excavator comprises an energy accumulator one-way valve block 19, wherein an oil inlet of the energy accumulator one-way valve block 19 is connected with a pressure reducing valve 18, and an oil outlet of the energy accumulator one-way valve block 19 is connected with an on-off electromagnetic valve block assembly 2; the actuating element comprises a rotary motor 4, a bucket rod oil cylinder 5, a bulldozer oil cylinder 6, a traveling motor 7, a breaking hammer 9, a movable arm oil cylinder 10 and a bucket oil cylinder 11, wherein the main control valve 1 is respectively connected with the rotary motor 4, the bucket rod oil cylinder 5, the bulldozer oil cylinder 6, the traveling motor 7, the breaking hammer 9, the movable arm oil cylinder 10 and the bucket oil cylinder 11; the electric control open throttle hydraulic system of the excavator further comprises a control unit ECU17, wherein the control unit ECU17 is respectively connected with the left operating handle 13, the right operating handle 14, the left foot valve 15 and the right foot valve 16, and the control unit ECU17 is also connected with the electromagnetic valve block assembly 12 through electric signals; the switch electromagnetic valve block assembly 2 comprises a switch electromagnetic valve VA1 and a switch electromagnetic valve VA2, wherein the switch electromagnetic valve VA1 is connected with the switch electromagnetic valve VA2 in parallel and then is connected with an oil outlet of the energy accumulator one-way valve block 19; the main pump 3 comprises a plunger pump P1, a plunger pump P2 and a gear pump P3; the main control valve 1 is a sheet type throttling main control valve; the left operating handle 13 and the right operating handle 14 are both electric control handles. The other parts are the same as in example 1.
The main pump 3 comprises a plunger pump P1, a plunger pump P2 and a gear pump P3, which correspond to three oil ports, namely an oil port A1, an oil port A2 and an oil port A3, respectively, wherein the oil port A1 and the oil port A2 are two linked oil outlets, namely the displacement of the two oil outlets is always equal, the displacement of the plunger pump P1 and the displacement of the plunger pump P2 are adjustable, the larger the pressure of the oil outlet, the smaller the displacement, the smaller the pressure, and the larger the flow to match the power of an engine; the displacement of the gear pump P3 is not adjustable.
The main control valve 1 is a sheet type throttling main control valve, namely the main control valve 1 is formed by connecting a plurality of valve bodies through bolts, and except end covers on two sides, as shown in fig. 4, each sheet is sequentially provided with a rotary joint, a bulldozer blade joint, a P3 oil inlet joint, a bucket rod joint, a movable arm joint, a left walking joint, P1 and P2 oil inlet joints, a right walking joint, a movable arm joint, a bucket rod joint and a bucket joint from left to right. The executing elements comprise a rotary motor 4, a bucket rod oil cylinder 5, a bulldozer oil cylinder 6, a walking motor 7, a breaking hammer 9, a movable arm oil cylinder 10 and a bucket oil cylinder 11, and the auxiliary elements comprise pipelines, joints and the like.
As shown in fig. 2, an oil port A3 of the gear pump P3 is connected to the main control valve 1, a path is connected to the pressure reducing valve 18, the pressure reducing valve 18 reduces the outlet pressure of the gear pump P3 to 4MPa, an oil outlet of the pressure reducing valve 18 is connected to the on-off solenoid valve block assembly 2, the on-off solenoid valve VA1 and the on-off solenoid valve VA2 are mounted on the on-off solenoid valve block assembly 2, the on-off solenoid valve VA1 is a pressure cut-off valve of the on-off solenoid valve block assembly 2, the oil inlet of the solenoid valve block assembly 12 is connected to high-pressure pilot oil, and the oil inlet of the solenoid valve block assembly 12 is connected to return oil when the pressure is cut-off.
The invention has no independent pilot pump, and the pilot pressure is obtained by the decompression of the main pump 3; after the oil port A3 of the main pump 3 passes through the pressure reducing valve 18 and the accumulator check valve block 19, the pressure of the oil port A3 is reduced to a basic stable value, and is the pilot pressure; the pilot pressure is divided into two paths on the switch electromagnetic valve block assembly 2, and one path passes through the switch electromagnetic valve VA2 to control the travelling speed; solenoid valve VA1 is switched to provide pressurized oil to solenoid valve block assembly 12.
As shown in fig. 3, the electromagnetic valve block assembly 12 is an integrated electromagnetic valve group which is arranged independently, and is provided with 16 electromagnetic valves VB1 to VB8 and VC1 to VC 8; VB6 is an on-off electromagnetic valve, and the balance is a proportional electromagnetic valve. The solenoid valve block assembly 12 has one or more Pp ports, one or more T ports, and a C port corresponding to the associated main valve stem. As shown in fig. 5, two types of oil channels are arranged in the electromagnetic valve block assembly 12, namely an oil return channel 20 which is connected with a T-port, and oil in the electromagnetic valve block assembly is low-pressure oil; and secondly, an oil inlet duct 21 is connected with a Pp port, oil in the oil inlet duct is high-pressure oil, and Pp pressure oil is provided by a switching electromagnetic valve VA 1. The outlet C of the electromagnetic valve (VB 1-VB 8 or any one of VC 1-VC 8) is connected with the pilot port of the valve rod of the main control valve 1, when the oil is high-pressure oil, the high-pressure oil directly acts on the end surface of the valve rod, and the hydraulic force overcomes the spring force on the valve rod to push the valve rod to act, so that corresponding action is realized.
The switch electromagnetic valve VB6 controls the transposition of the P3 oil inlet joint in the main control valve 1, when the left and right walking are performed simultaneously, and one or more of the movable arm oil cylinder 10, the bucket rod oil cylinder 5 or the bucket oil cylinder 11 are performed simultaneously, the switch electromagnetic valve VB6 is electrified, the oil outlet of the switch electromagnetic valve VB6 outputs high pressure which is not more than the pressure Pp, the P3 oil inlet joint transposition is realized, and the straight walking function of the excavator is realized, namely the walking motors 7 on the left side and the right side obtain the same flow input. The other 15 proportional solenoid valves respectively control corresponding valve rods, so as to control corresponding actions.
When the excavator is in operation, an operator transmits willingness to the handle, the handle receives an angle given by the operator and transmits signals such As voltage, current and the like to the control unit ECU17, the control unit ECU17 processes the received signals and outputs corresponding currents, the proportional solenoid valves (VB 1-VB 5, VB 7-VB 8, VC 1-VC 8) can output different pressure outputs Px with the relation between Px and the handle angle a which is not greater than the pressure Pp according to the obtained current inputs of different magnitudes, the relation between Px and the handle angle a is shown in fig. 7, the operator needs to enable the excavator to perform left turning action by taking the excavator As an example, the handle is operated to input the handle at a certain angle, the input finally electrifies the proportional solenoid valve 8 for controlling the left turning, the output port C of the proportional solenoid valve VB8 outputs certain pilot oil with pressure, the port C of the pilot oil with pressure acts on the xAs port on the turning link on the main control valve 1 and pushes the turning link valve core to move left, and the As port of the valve body 22 outputs pressure to enable the turning motor 4 to act, and the excavator to turn left; after the handle is reset, the input current of the proportional electromagnetic valve VB8 is zero, the output pressure of the outlet C of the proportional electromagnetic valve VB8 is zero, the xAs pressure on the rotary connecting valve is zero, the valve rod is recovered to the middle position, the As pressure output of the valve body 22 is interrupted, and the excavator stops turning left. Other actions are as described above.
As shown in fig. 7, a control curve of a proportional solenoid valve (e.g., VB 1) is shown, the abscissa takes the angle a of a handle or a foot valve as an input, and the ordinate represents the output pilot pressure Px of the proportional solenoid valve, for example, the proportional solenoid valve controls the large chamber oil feed of the bucket cylinder 11, the handle does not operate, the proportional solenoid valve is not energized, the pilot pressure output by the proportional solenoid valve is zero, and the valve rod does not operate, so the large chamber of the bucket cylinder 11 does not operate; the handle acts, the control unit ECU17 starts to capture an intermediate conversion signal (such as a voltage U or a resistor R) of the handle, then inputs a current signal I to the proportional solenoid valve after the handle angle a exceeds the idle stroke a1, under the action of the current signal I, the proportional solenoid valve starts to output a pressure Px1, the handle angle continues to increase, after the handle angle a2 is reached, the proportional solenoid valve is fully opened, the output pressure reaches a maximum value Px2, under the action of the pressure Px, the bucket valve rod of the bucket cylinder 11 acts, the main control valve 1 supplies oil to a large cavity of the bucket cylinder 11, and the bucket starts to act.
Wherein a1 represents the idle stroke of a handle or a pedal valve, the handle is a left operating handle 13 or a right operating handle 14, and the pedal valve is a left pedal valve 15 or a right pedal valve 16.
Claims (8)
1. The utility model provides an electronic accuse open throttle hydraulic system of excavator, includes master control valve (1), main pump (3) and executive component, executive component is connected its characterized in that with master control valve (1) and main pump (3) respectively: the electric control open type throttling hydraulic system of the excavator comprises an electromagnetic valve block assembly (12), an on-off electromagnetic valve block assembly (2), a pressure reducing valve (18) and an energy accumulator one-way valve block (19), wherein the electromagnetic valve block assembly (12) is respectively connected with a main control valve (1) and the on-off electromagnetic valve block assembly (2), and the pressure reducing valve (18) is respectively connected with the on-off electromagnetic valve block assembly (2) and a main pump (3); after the oil port A3 of the main pump (3) passes through the pressure reducing valve (18) and the accumulator check valve block (19), the pressure of the oil port A3 is reduced to a basic stable value, and is the pilot pressure.
2. The electronically controlled open throttle hydraulic system of an excavator of claim 1, wherein: the main control valve (1) is connected with the rotary motor (4), the bucket rod oil cylinder (5), the bulldozer oil cylinder (6), the walking motor (7), the breaking hammer (9), the movable arm oil cylinder (10) and the bucket oil cylinder (11) respectively.
3. The excavator controlled open throttle hydraulic system of claim 2 wherein: an oil inlet of the energy accumulator one-way valve block (19) is connected with the pressure reducing valve (18), and an oil outlet is connected with the switch electromagnetic valve block assembly (2).
4. The electronically controlled open throttle hydraulic system of an excavator of claim 3, wherein: the electric control open throttle hydraulic system of the excavator further comprises a control unit ECU (17), the control unit ECU (17) is respectively connected with the left operating handle (13), the right operating handle (14), the left foot valve (15) and the right foot valve (16), and the control unit ECU (17) is further connected with the electromagnetic valve block assembly (12) through electric signals.
5. The electronically controlled open throttle hydraulic system of an excavator of claim 4, wherein: the on-off electromagnetic valve block assembly (2) comprises an on-off electromagnetic valve VA1 and an on-off electromagnetic valve VA2, and the on-off electromagnetic valve VA1 is connected with the on-off electromagnetic valve VA2 in parallel and then is connected with an oil outlet of the energy accumulator one-way valve block (19).
6. The electronically controlled open throttle hydraulic system of an excavator of claim 5, wherein: the main pump (3) includes a plunger pump P1, a plunger pump P2, and a gear pump P3.
7. The electronically controlled open throttle hydraulic system of an excavator of claim 6, wherein: the main control valve (1) is a sheet type throttling main control valve.
8. The excavator controlled open throttle hydraulic system of claim 7 wherein: the left operating handle (13) and the right operating handle (14) are both electric control handles.
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 |
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| 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 |
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| CN108505579A CN108505579A (en) | 2018-09-07 |
| CN108505579B true CN108505579B (en) | 2023-08-18 |
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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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