CN204551557U - A kind of hydraulic crawler excavator - Google Patents
A kind of hydraulic crawler excavator Download PDFInfo
- Publication number
- CN204551557U CN204551557U CN201420866062.6U CN201420866062U CN204551557U CN 204551557 U CN204551557 U CN 204551557U CN 201420866062 U CN201420866062 U CN 201420866062U CN 204551557 U CN204551557 U CN 204551557U
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- valve
- control valve
- swing arm
- directional control
- multiple directional
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Abstract
The utility model discloses a kind of hydraulic crawler excavator.This hydraulic crawler excavator is connected with dipper angular transducer by the input port arranging controller, obtain dipper angle [alpha], the delivery outlet of controller respectively with the electromagnetic signal input port of the first proportioning valve, the electromagnetic signal input port of the second proportioning valve is connected with two electromagnetic signal input ports of multiple directional control valve, the oil-out of the first proportioning valve, the oil-out of the second proportioning valve is connected with guide's hydraulic fluid port of swing arm main control valve respectively, the actuator port of multiple directional control valve respectively with the oil-in of the first proportioning valve, the oil-in of the second proportioning valve is connected with guide's hydraulic fluid port of swing arm main control valve, the oil-out of two reducing valve of swing arm pilot handle is connected with two oil-ins of multiple directional control valve respectively.And pass through the valve core opening of control first proportioning valve and the second proportioning valve, and swing arm main control valve valve core opening area, the slow operation of adjustment swing arm, and then improve the smoothening capability of hydraulic crawler excavator.
Description
Technical field
The utility model relates to excavator field, particularly relates to a kind of hydraulic crawler excavator.
Background technology
Mini-excavator application widely, has served multiple fields of national economy.Grading operation is one of common operating mode of mini-excavator, mainly relies on swing arm to promote and the composite move of dipper adduction carries out smooth to ground, and the quality of smoothening capability reflects the level of overall performance to a certain extent, is thus subject to the attention of each main frame producer.
Because mini-excavator needs only to arrange a hydraulic pump fuel feeding according to its own traffic, think and avoid the exercise not harmony that causes of actuator load difference, general employing has the load-sensitive hydraulic system of flow anti-saturation function, that is the flow proportional and each execution load pressure size that flow into actuator have nothing to do, the openings of sizes only controlling spool with main valve is relevant, be exactly relevant with the pilot pressure of control bound core commutation furtherly, finally sum up in the point that in practical operation, depend on the inclination angle of pilot handle during operator operated pilot handle exactly, therefore the combination of grading operation inherently swing arm and dipper two handle change of pitch angles.
When inside level land, swing arm and dipper handle are pulled to inclination maximum simultaneously, and then swing arm handle is slowly pushed back meta, move, thus ensure bucket tooth kiss the earth all the time to slow down the swing arm rate of climb on the scraper bowl compensating dipper arcuate movement curve and cause; In like manner during outside level land, dipper handle is pulled to inclination maximum at the very start, slowly promotes swing arm handle to inclination maximum simultaneously.
In whole grading operation process, dipper handle is in inclination maximum all the time, and swing arm handle is less than in the scope of 90 ° at dipper and ground-angle α and there is slow operation, as shown in Figure 1.Skilled operator is easy to control swing arm and dipper composite move and realizes scraper bowl crown be adjacent to ground all the time in the process of level land, unskilled operator is then difficult to the laminating keeping crown and ground in the process of whole level land, thus causing ground relief, leveling effect is not good.
In prior art, when grading operation, although the method increasing suitable throttle orifice in action faster executing agency loop can improve the performance on level land, efficiency and the harmony of the complete machine under other operating mode can be affected so undoubtedly.
If the hydraulic pump adopting two flows less replaces single oil pump feed, Dual-pump flow-converging is cancelled during grading operation, two pumps are made to supply swing arm and bucket arm cylinder respectively, although the method avoids the mutual interference of swing arm and dipper flow, improve level land handling, but add the complexity of hydraulic system simultaneously.Putting before this, such as swing arm promotes the action such as the side of getting rid of, the excavation of dipper adduction all needs Dual-pump flow-converging, consider from the reliability of hydraulic system, the increase of series connection link can cause the reduction of system reliability, and above two kinds of methods are all only confined to improving of smoothening capability, can not ensure that unskilled operator also can obtain desirable grading operation effect easily theoretically.
Utility model content
The technical problems to be solved in the utility model is that existing hydraulic crawler excavator control swing arm delays operating difficulties, and then causes grading operation poor performance.
According to the utility model on the one hand, a kind of hydraulic crawler excavator is proposed, comprise: controller (1), the first proportioning valve (2), the second proportioning valve (3), swing arm pilot handle (4), multiple directional control valve (5), swing arm main control valve (6) and dipper angular transducer (7), wherein:
The input port of described controller (1) is connected with the delivery outlet of described dipper angular transducer (7), first delivery outlet of described controller (1) is connected with the electromagnetic signal input port of described first proportioning valve (2), and the second delivery outlet of described controller (1) is connected with the electromagnetic signal input port of described second proportioning valve (3);
The oil-out of described first proportioning valve (2) is connected with the upward leader hydraulic fluid port of described swing arm main control valve (6), and the oil-in of described first proportioning valve (2) is connected with the first actuator port of described multiple directional control valve (5);
The oil-out of described second proportioning valve (3) is connected with the decline guide hydraulic fluid port of described swing arm main control valve (6), and the oil-in of described second proportioning valve (3) is connected with the 4th actuator port of described multiple directional control valve (5);
The oil-out of two reducing valve of described swing arm pilot handle (4) is connected with two oil-ins of described multiple directional control valve (5) respectively;
First electromagnetic signal input port of described multiple directional control valve (5) is connected with the 3rd delivery outlet of described controller (1), and the second electromagnetic signal input port of described multiple directional control valve (5) is connected with the 4th delivery outlet of described controller (1);
The upward leader hydraulic fluid port of described swing arm main control valve (6) is connected with the second actuator port of described multiple directional control valve (5), and the decline guide hydraulic fluid port of described swing arm main control valve (6) is connected with the 3rd actuator port of described multiple directional control valve (5).
Further, described first proportioning valve (2) and the second proportioning valve (3) simultaneously electric or simultaneously dead electricity.
Further, described multiple directional control valve (5) adopts DC electromagnet, from the storage battery power supply of described hydraulic crawler excavator.
Further, described first proportioning valve (2) and the second proportioning valve (3) are identical bi-bit bi-pass electric proportional valve;
Further, described multiple directional control valve (5) is three six electric change valves.
Compared with prior art, the utility model is by arranging controller (1), be connected with dipper angular transducer (7), obtain dipper angle [alpha], and by controlling the valve core opening of described first proportioning valve (2) and the second proportioning valve (3), and control swing arm main control valve (6) valve core opening area, the slow operation of adjustment swing arm, and then improve the smoothening capability of hydraulic crawler excavator.
By referring to the detailed description of accompanying drawing to exemplary embodiment of the present utility model, further feature of the present utility model and advantage thereof will become clear.
Accompanying drawing explanation
What form a part for manual drawings describes embodiment of the present utility model, and together with the description for explaining principle of the present utility model.
With reference to accompanying drawing, according to detailed description below, clearly the utility model can be understood, wherein:
Fig. 1 is the bucket tooth horizontally face straight line digging schematic diagram of scraper bowl.
Fig. 2 is the structural representation of an embodiment of the utility model hydraulic crawler excavator.
Detailed description of the invention
Various exemplary embodiment of the present utility model is described in detail now with reference to accompanying drawing.It should be noted that: unless specifically stated otherwise, otherwise positioned opposite, the numerical expression of the parts of setting forth in these embodiments and step and numerical value do not limit scope of the present utility model.
Meanwhile, it should be understood that for convenience of description, the size of the various piece shown in accompanying drawing is not draw according to the proportionate relationship of reality.
Illustrative to the description only actually of at least one exemplary embodiment below, never as any restriction to the utility model and application or use.
May not discuss in detail for the known technology of person of ordinary skill in the relevant, method and apparatus, but in the appropriate case, described technology, method and apparatus should be regarded as a part of authorizing manual.
In all examples with discussing shown here, any occurrence should be construed as merely exemplary, instead of as restriction.Therefore, other example of exemplary embodiment can have different values.
It should be noted that: represent similar terms in similar label and letter accompanying drawing below, therefore, once be defined in an a certain Xiang Yi accompanying drawing, then do not need to be further discussed it in accompanying drawing subsequently.
For making the purpose of this utility model, technical scheme and advantage clearly understand, below in conjunction with specific embodiment, and with reference to accompanying drawing, the utility model is further described.
Fig. 2 is the structural representation of an embodiment of the utility model hydraulic crawler excavator.This structure comprises: controller 1, first proportioning valve 2, second proportioning valve 3, swing arm pilot handle 4, multiple directional control valve 5, swing arm main control valve 6 and dipper angular transducer 7, wherein:
The input port of described controller 1 is connected with the delivery outlet of described dipper angular transducer 7, first delivery outlet of described controller 1 is connected with the electromagnetic signal input port of described first proportioning valve 2, and the second delivery outlet of described controller 1 is connected with the electromagnetic signal input port of described second proportioning valve 3;
The oil-out of described first proportioning valve 2 is connected with the upward leader hydraulic fluid port of described swing arm main control valve 6, and the oil-in of described first proportioning valve 2 is connected with the first actuator port of described multiple directional control valve 5;
The oil-out of described second proportioning valve 3 is connected with the decline guide hydraulic fluid port of described swing arm main control valve 6, and the oil-in of described second proportioning valve 3 is connected with the 4th actuator port of described multiple directional control valve 5;
The oil-out of two reducing valve of described swing arm pilot handle 4 is connected with two oil-ins of described multiple directional control valve 5 respectively;
First electromagnetic signal input port of described multiple directional control valve 5 is connected with the 3rd delivery outlet of described controller 1, and the second electromagnetic signal input port of described multiple directional control valve 5 is connected with the 4th delivery outlet of described controller 1;
The upward leader hydraulic fluid port of described swing arm main control valve 6 is connected with the second actuator port of described multiple directional control valve 5, and the decline guide hydraulic fluid port of described swing arm main control valve 6 is connected with the 3rd actuator port of described multiple directional control valve 5.
Wherein, described first proportioning valve 2 is identical bi-bit bi-pass electric proportional valve with the second proportioning valve 3;
Described multiple directional control valve 5 is three six electric change valves, adopts DC electromagnet, from the storage battery power supply of described hydraulic crawler excavator, without the need to arranging rectifier in addition.
In this embodiment, when hydraulic crawler excavator carries out grading operation, controller 1 is opened, and dipper angular transducer 7 is for sending to controller 1 by the dipper angle [alpha] of collection.The measurement category of described dipper angular transducer 7 is 0 ° to 180 °, and resolution ratio and hysteresis error are all less than 0.1 °.It will be understood by those of skill in the art that grading operation comprises bucket tooth horizontally face straight line digging, also comprise bucket tooth along sloping floor straight line digging, described dipper angular transducer 7 only for citing, should not be construed restriction of the present utility model.
Described controller 1 is for judging whether dipper angle [alpha] diminishes.
If dipper angle [alpha] is diminishing, namely hydraulic crawler excavator is carrying out inside grading operation, the first electromagnetic signal that described controller 1 controls described multiple directional control valve 5 obtains electric second electromagnetic signal dead electricity, described first proportioning valve 2 connecting system loop, guide oil is connected with the upward leader mouth of swing arm main control valve 6 after flowing through described first proportioning valve 2, and the decline guide oil of described swing arm main control valve 6 is communicated with tank drainback through the 3rd actuator port of multiple directional control valve 5 with swing arm pilot handle 4.
In the inside level land stage, if described controller 1 judges that dipper angle [alpha] is less than or equal to 90 °, first proportioning valve 2 obtains electric, pilot pressure is through the throttling of the first proportioning valve 2, pressure drop, swing arm main control valve 6 valve core opening area diminishes, and swing arm speed declines to coordinate dipper to realize scraper bucket tooth rectilinear motion.
If described controller 1 judges that dipper angle [alpha] is greater than 90 °, the first proportioning valve 2 dead electricity, described first proportioning valve 2 valve core opening standard-sized sheet, pilot pressure acts on swing arm main control valve 6 spool with maximum value.
If dipper angle [alpha] is large in change, namely hydraulic crawler excavator is carrying out outside grading operation, the first electromagnetic signal dead electricity second electromagnetic signal that described controller 1 controls described multiple directional control valve 5 obtains electric, described second proportioning valve 3 connecting system loop, guide oil is connected with the decline pilot port of swing arm main control valve 6 after flowing through described second proportioning valve 3, and the upward leader oil of described swing arm main control valve 6 is communicated with tank drainback through the second actuator port of multiple directional control valve 5 with swing arm pilot handle 4.
In the outside level land stage, if described controller 1 judges that dipper angle [alpha] is less than or equal to 90 °, second proportioning valve 3 obtains electric, pilot pressure is through the throttling of the second proportioning valve 3, pressure drop, swing arm main control valve 6 valve core opening area diminishes, and swing arm speed declines to coordinate dipper to realize scraper bucket tooth rectilinear motion.
If described controller 1 judges that dipper angle [alpha] is greater than 90 °, the second proportioning valve 3 dead electricity, described second proportioning valve 3 valve core opening standard-sized sheet, pilot pressure acts on swing arm main control valve 6 spool with maximum value.
Described controller 1, according to the size of dipper angle [alpha] determination electric current, is adjusted the valve core opening of described first proportioning valve 2 and the second proportioning valve 3, carries out throttling to guide oil by the size of given electric current, and then controls swing arm main control valve 6 valve core opening area.
Wherein, the size of electric current determines the pressure of swing arm guide, the pressure of swing arm guide determines swing arm main control valve 6 spool displacement, swing arm main control valve 6 spool displacement determines swing arm main control valve 6 valve core opening area, swing arm main control valve 6 valve core opening area determines boom cylinder flow, and boom cylinder flow determines swing arm speed, according to the movement locus of swing arm during level land and bucket rod structure part, swing arm speed and dipper angle [alpha] have one-to-one relationship, therefore dipper angle [alpha] and electric current also one_to_one corresponding.The corresponding relation of dipper angle and size of current, can calculate according to following formula:
Wherein α is dipper angle; I is electric current; η
1for the ratio of swing arm main control valve 6 valve core opening area and spool displacement; η
2for the ratio of spool displacement and swing arm pilot pressure; E is the swing arm pilot force of electric proportional valve output and the ratio of current i, and dissimilar electric proportional valve e value is different; Δ p is valve port chock pressure difference; S
1for the large cavity area of boom cylinder; S
2for the large cavity area of bucket arm cylinder; A
1for dipper spool maximum open area; Because swing arm and horizontal plane angle change less, ignore its change, can unify to substitute into formula by 50 °.
Due to the area discrepancy of swing arm and the large loculus of bucket arm cylinder, under equal angular α prerequisite, during inside level land the first proportioning valve 2 electric current value must electric current value be different with the second proportioning valve 3 during outside level land.
If dipper angle [alpha] is constant, described controller 1 controls the first electromagnetic signal and the second electromagnetic signal dead electricity simultaneously of described multiple directional control valve 5.
In embodiment of the present utility model, from the angle of anxious operation gentle operation, grading operation operating mode is divided into two processes, when namely dipper angle [alpha] is greater than 90 °, dipper, swing arm are all the processes of anxious operation, when dipper angle [alpha] is less than or equal to 90 °, dipper suddenly operates and the slow operation of swing arm.Manageable swing arm slow operation operating mode is not allowed for operator, the utility model gathers the angle of dipper, real time coordination controls swing arm speed and dipper speeds match, the bucket tooth of scraper bowl is made to keep rectilinear motion in the horizontal plane, and operator only need carry out simple anxious operation in the process of whole level land, namely to maximum position only need be moved dipper and swing arm handle in inside level land simultaneously, onto maximum position only need be shifted dipper and swing arm handle in outside level land simultaneously, this shirtsleeve operation not only makes unskilled operator can obtain desirable grading operation effect easily, also reduce the labour intensity of energy high concentration when operator carries out delaying operation simultaneously.
In addition, because the utility model still adopts single oil pump feed, and only gather dipper angle-data, which avoid and adopt double pump respectively to the Dual-pump flow-converging hydraulic series link that swing arm bucket arm cylinder fuel feeding brings to the technical scheme improving level land handling, therefore there is higher reliability.
Another embodiment of the present utility model, described first proportioning valve 2 and the second proportioning valve 3 simultaneously electric or simultaneously dead electricity.Multiple directional control valve 5 in the first electromagnetic signal and the second electromagnetic signal any one work time, always there is the work of a proportioning valve connecting system, and another proportioning valve not connecting system, why control in this case two proportioning valves simultaneously electric and dead electricity, the harmony of swing arm and dipper action when object is to guarantee that inside and outside level land operating mode switches fast.When such as inside level land completes and enters outside level land, this Time Controller 1 is experienced dipper angle [alpha] and is become increase from reduction, multiple directional control valve 5 first electromagnetic signal dead electricity immediately, second electromagnetic signal immediately electric, second proportioning valve 3 connecting system, now the second proportioning valve 3 is adjusted opening by controller 1 according to the current value that dipper angle [alpha] sends and is carried out throttling to guide oil, thus controls swing arm main control valve 6 spool and move to default desired open area, systems linking.If not simultaneously electric, although do not affect system theoretically, in fact will inevitably cause the inharmonious of swing arm and dipper action the time lag of hydraulic system.
In embodiment of the present utility model, by described first proportioning valve 2 and the second proportioning valve 3 simultaneously electric or dead electricity simultaneously.The harmony of swing arm and dipper action when guaranteeing that inside and outside level land operating mode switches fast, improves grading operation efficiency.
Another embodiment of the utility model, controller (1) cuts out, guide oil is communicated with decline pilot port with the upward leader mouth of the 3rd actuator port with described swing arm main control valve (6) through multiple directional control valve (5) second actuator port by the oil-out of described swing arm pilot handle (4), control the commutation of swing arm main control valve (6) spool, complete swing arm lifting action.
In embodiment of the present utility model, described controller 1 is only opened in grading operation, and rest working conditions is all closed.Therefore grading operation has very strong independence, is independent of each other with other working conditions, avoids swing arm speed and declines and the reduction of the overall efficiency that causes and harmony.
So far, the utility model is described in detail.In order to avoid covering design of the present utility model, details more known in the field are not described.Those skilled in the art, according to description above, can understand how to implement technical scheme disclosed herein completely.
Although be described in detail specific embodiments more of the present utility model by example, it should be appreciated by those skilled in the art, above example is only to be described, instead of in order to limit scope of the present utility model.It should be appreciated by those skilled in the art, when not departing from scope and spirit of the present utility model, above embodiment can be modified.Scope of the present utility model is limited by claims.
Claims (9)
1. a hydraulic crawler excavator, comprise: controller (1), the first proportioning valve (2), the second proportioning valve (3), swing arm pilot handle (4), multiple directional control valve (5), swing arm main control valve (6) and dipper angular transducer (7), wherein:
The input port of described controller (1) is connected with the delivery outlet of described dipper angular transducer (7), first delivery outlet of described controller (1) is connected with the electromagnetic signal input port of described first proportioning valve (2), and the second delivery outlet of described controller (1) is connected with the electromagnetic signal input port of described second proportioning valve (3);
The oil-out of described first proportioning valve (2) is connected with the upward leader hydraulic fluid port of described swing arm main control valve (6), and the oil-in of described first proportioning valve (2) is connected with the first actuator port of described multiple directional control valve (5);
The oil-out of described second proportioning valve (3) is connected with the decline guide hydraulic fluid port of described swing arm main control valve (6), and the oil-in of described second proportioning valve (3) is connected with the 4th actuator port of described multiple directional control valve (5);
The oil-out of two reducing valve of described swing arm pilot handle (4) is connected with two oil-ins of described multiple directional control valve (5) respectively;
First electromagnetic signal input port of described multiple directional control valve (5) is connected with the 3rd delivery outlet of described controller (1), and the second electromagnetic signal input port of described multiple directional control valve (5) is connected with the 4th delivery outlet of described controller (1);
The upward leader hydraulic fluid port of described swing arm main control valve (6) is connected with the second actuator port of described multiple directional control valve (5), and the decline guide hydraulic fluid port of described swing arm main control valve (6) is connected with the 3rd actuator port of described multiple directional control valve (5).
2. hydraulic crawler excavator according to claim 1, comprising:
Described first proportioning valve (2) and the second proportioning valve (3) simultaneously electric or simultaneously dead electricity.
3. hydraulic crawler excavator according to claim 1 and 2, comprising:
Described multiple directional control valve (5) adopts DC electromagnet, from the storage battery power supply of described hydraulic crawler excavator.
4. hydraulic crawler excavator according to claim 1 and 2, comprising:
Described first proportioning valve (2) and the second proportioning valve (3) are identical bi-bit bi-pass electric proportional valve.
5. hydraulic crawler excavator according to claim 1 and 2, comprising:
Described multiple directional control valve (5) is three six electric change valves.
6. hydraulic crawler excavator according to claim 3, comprising:
Described first proportioning valve (2) and the second proportioning valve (3) are identical bi-bit bi-pass electric proportional valve.
7. hydraulic crawler excavator according to claim 3, comprising:
Described multiple directional control valve (5) is three six electric change valves.
8. hydraulic crawler excavator according to claim 4, comprising:
Described multiple directional control valve (5) is three six electric change valves.
9. hydraulic crawler excavator according to claim 6, comprising:
Described multiple directional control valve (5) is three six electric change valves.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420866062.6U CN204551557U (en) | 2014-12-31 | 2014-12-31 | A kind of hydraulic crawler excavator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420866062.6U CN204551557U (en) | 2014-12-31 | 2014-12-31 | A kind of hydraulic crawler excavator |
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| Publication Number | Publication Date |
|---|---|
| CN204551557U true CN204551557U (en) | 2015-08-12 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420866062.6U Withdrawn - After Issue CN204551557U (en) | 2014-12-31 | 2014-12-31 | A kind of hydraulic crawler excavator |
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| Country | Link |
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| CN (1) | CN204551557U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105804137A (en) * | 2014-12-31 | 2016-07-27 | 徐工集团工程机械股份有限公司 | Hydraulic excavator and land leveling control method of hydraulic excavator |
-
2014
- 2014-12-31 CN CN201420866062.6U patent/CN204551557U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105804137A (en) * | 2014-12-31 | 2016-07-27 | 徐工集团工程机械股份有限公司 | Hydraulic excavator and land leveling control method of hydraulic excavator |
| CN105804137B (en) * | 2014-12-31 | 2018-03-09 | 徐工集团工程机械股份有限公司 | A kind of hydraulic crawler excavator and its method for carrying out level land control |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20150812 Effective date of abandoning: 20180309 |
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| AV01 | Patent right actively abandoned |