CN102889253A - Hydraulic system and engineering machinery - Google Patents
Hydraulic system and engineering machinery Download PDFInfo
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- CN102889253A CN102889253A CN2012103520564A CN201210352056A CN102889253A CN 102889253 A CN102889253 A CN 102889253A CN 2012103520564 A CN2012103520564 A CN 2012103520564A CN 201210352056 A CN201210352056 A CN 201210352056A CN 102889253 A CN102889253 A CN 102889253A
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- oil
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- hydraulic system
- oil circuit
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Abstract
The invention relates to the field of engineering machinery, and discloses a hydraulic system and engineering machinery. The hydraulic system comprises an oil tank, a variable pump, a differential pressure valve, a proportional reversing valve and a hydraulic execution element, wherein an oil inlet of the variable pump is connected to the oil tank; an oil outlet of the variable pump is connected to a main oil inlet of the proportional reversing valve through a first oil path; a main oil returning port of the proportional reversing valve is connected to the oil tank through a second oil path; a first working oil port and a second working oil port of the proportional reversing valve are respectively connected to an oil inlet and an oil outlet of the hydraulic execution element through a third oil path and a fourth oil path; an oil inlet of the differential pressure valve is connected to the first oil path, and an oil outlet of the differential pressure valve is connected to the oil tank; a control oil port of the differential pressure valve is connected to a control oil path; and pressure oil of the control oil path is from one, which is relatively high in oil pressure, of the third oil path and the fourth oil path. The hydraulic system has the characteristics of a valve control hydraulic system and a pump control hydraulic system; under a working condition of low flow, the hydraulic system is high in dynamic response and high in control precision; and under a working condition of high flow, the system is high in efficiency.
Description
Technical field
The present invention relates to engineering machinery field, particularly a kind of hydraulic system and engineering machinery.
Background technique
At present, medium and small tonnage hoist extensively adopts valve control hydraulic system, then adopts the pump control hydraulic system than hoister in large tonnage.Valve control hydraulic system is also referred to as throttling control hydraulic system, generally formed by metering pump and Flow valve (relief valve, throttle valve etc.), in use, the size that can pass through the circulation area of adjust flux valve flows into or flows out the flow of executive component with change, and then changes the speed of executive component; The pump control hydraulic system is also referred to as volume control hydraulic system, generally formed by variable displacement pump and regular tap valve or selector valve, in use, can realize by changing the variable pump delivery change of the speed of executive component, switch valve and selector valve only have the effect of break-make oil circuit and commutation.
Valve control hydraulic system has advantages of that dynamic response is fast, control accuracy is high, but efficient is lower, generally be applicable to occasion that rapidity, fine motion are had relatively high expectations, and the pump control hydraulic system has advantages of that efficient is high, but dynamic response is slow, control accuracy is lower, generally is applicable to the occasion not high to rapidity requirement, therefore, how designing a kind of hydraulic system that has simultaneously above-mentioned two kinds of advantages, is the technical problem that those skilled in the art need to be resolved hurrily.
Summary of the invention
In view of this, the present invention is intended to propose a kind of hydraulic system, and this hydraulic system has valve control hydraulic system and pump control hydraulic advantage of system simultaneously, and namely dynamic response is fast under the operating mode of small flow, control accuracy is high, and system effectiveness is high under the operating mode of large flow.The invention allows for a kind of engineering machinery.
Particularly, on the one hand, hydraulic system provided by the invention comprises fuel tank, variable displacement pump, pressure difference valve, proportional reversing valve and hydraulic actuator; The filler opening of described variable displacement pump is connected to fuel tank, and the oil outlet of described variable displacement pump is connected to the main filler opening of described proportional reversing valve by the first oil circuit; The main return opening of described proportional reversing valve is connected to fuel tank by the second oil circuit, and the first actuator port of described proportional reversing valve and the second actuator port are connected to respectively the oil inlet and outlet of described hydraulic actuator by the 3rd oil circuit and the 4th oil circuit; The filler opening of described pressure difference valve is connected to described the first oil circuit, the oil outlet of described pressure difference valve is connected to fuel tank, the control port of described pressure difference valve is connected to oil circuit control, and the pressure oil of described oil circuit control comes from oil pressure the grater of described the 3rd oil circuit and described the 4th oil circuit.
Further, described hydraulic system also comprises shuttle valve; Two input ends of described shuttle valve are connected to respectively described the 3rd oil circuit and described the 4th oil circuit, and the output terminal of described shuttle valve is connected to described oil circuit control.
Further, described proportional reversing valve is electro-hydraulic proportion reversing valve.
Further, described proportional reversing valve is three-position four-way valve, in the first job position, described main filler opening is communicated in described the second actuator port, and described main return opening is communicated in described the first actuator port, in the second working position, described main filler opening disconnects, and described main return opening is communicated in described the first actuator port and described the second actuator port, in the 3rd working position, described main filler opening is communicated in described the first actuator port, and described main return opening is communicated in described the second actuator port.
Further, described hydraulic actuator is oil hydraulic motor or hydraulic jack.
On the other hand, a kind of engineering machinery provided by the invention is provided with above-mentioned each described hydraulic system.
Hydraulic system provided by the invention can work under the low flow rate condition and large flow rate working conditions under, when being in low flow rate condition, the controlled variable pump delivery is constant, guarantee that its flow that provides satisfies hydraulic actuator required, because proportional reversing valve has the ratio characteristic, but the passing ratio selector valve is regulated the input and output flow of hydraulic actuator, and pressure difference valve can guarantee that proportional reversing valve front and back pressure reduction is constant, make like this system have fast response time (fretting performance of hydraulic actuator is good), the characteristics that control accuracy is high, when being in large flow rate working conditions lower time, the spool aperture of control ratio selector valve is excessively to all-round switch, make proportional reversing valve not have the ratio characteristic, at this moment, pressure reduction will be less than the adjusting pressure of pressure difference valve before and after the proportional reversing valve, be not output flow of pressure difference valve, can realize adjusting to the hydraulic actuator input flow rate making system have the high characteristics of efficient by the controlled variable pump like this.
Engineering machinery provided by the invention is provided with above-mentioned hydraulic system, because above-mentioned hydraulic system has above-mentioned technique effect, therefore, this project machinery also has corresponding technique effect.
Description of drawings
The accompanying drawing that consists of a part of the present invention is used to provide a further understanding of the present invention, and illustrative examples of the present invention and explanation thereof are used for explaining the present invention, do not consist of improper restriction of the present invention.In the accompanying drawings:
The principle schematic of a kind of hydraulic system that Fig. 1 provides for the embodiment of the invention.
Label declaration:
1 fuel tank
2 variable displacement pumps
3 pressure difference valve
4 proportional reversing valves
5 shuttle valves
6 hydraulic actuators
01 first oil circuit
02 second oil circuit
03 the 3rd oil circuit
04 the 4th oil circuit
05 oil circuit control
P master's filler opening
T master's return opening
A the first actuator port
B the second actuator port
Embodiment
Should be pointed out that in this part that to the description of concrete structure and description order only be explanation to specific embodiment, should not be considered as that protection scope of the present invention is had any restriction.In addition, under the situation of not conflicting, embodiment and the feature among the embodiment in this part can make up mutually.
Please refer to Fig. 1, below with reference to the accompanying drawings the embodiment of the invention is elaborated.
As shown in the figure, this embodiment's hydraulic system mainly comprises fuel tank 1, variable displacement pump 2, pressure difference valve 3, proportional reversing valve 4, shuttle valve 5 and hydraulic actuator 6.
Wherein, proportional reversing valve 4 has main oil inlet P, main oil return inlet T, the first actuator port A and the second actuator port B; The filler opening of variable displacement pump 2 is connected to fuel tank 1, the oil outlet of variable displacement pump 2 is connected to the main oil inlet P of proportional reversing valve 4 by the first oil circuit 01, the main oil return inlet T of proportional reversing valve 4 is connected to (leading to) fuel tank 1 by the second oil circuit 02, and the first actuator port A of proportional reversing valve 4 and the second actuator port B are connected to respectively the oil inlet and outlet of hydraulic actuator 6 by the 3rd oil circuit 03 and the 4th oil circuit 04; The filler opening of pressure difference valve 3 is connected to the first oil circuit 01, and the oil outlet of pressure difference valve 3 is connected to shown in the fuel tank 1(figure as leading to fuel tank 1 by the second oil circuit 02); Two input ends of shuttle valve 5 are connected to respectively the 3rd oil circuit 03 and the 4th oil circuit 04, and the output terminal of shuttle valve 5 is connected to the oil-inlet end of oil circuit control 05, and the oil outlet end of oil circuit control 05 is connected to the control port of pressure difference valve 3.
Preferably, proportional reversing valve 4 is electro-hydraulic proportion reversing valve, more preferably, proportional reversing valve 4 is the three-position four-way valve of Y type for Median Function, (namely work in left position) in the first working position, the P mouth communicates with the B mouth, and the A mouth communicates with the T mouth, (namely work in meta) in the second working position, the P mouth disconnects, and A mouth and B mouth all communicate with the T mouth, (namely works in right position) in the 3rd working position, the P mouth communicates with the A mouth, and the B mouth communicates with the T mouth; In addition, the corresponding voltage signal of inputting by the ratio electromagnetic coil on proportional reversing valve can make spool produce displacement, and then obtains circulation area proportional to this voltage signal.
The working principle of above-mentioned hydraulic system once is described and controls process below in conjunction with concrete scene:
When system works in low flow rate condition lower time, for example, when hydraulic actuator 6 required flows during less than 40L/min, the discharge capacity of controlled variable pump 2 is constant, guarantee that its flow that provides is about 40L/min, because proportional reversing valve 4 has the ratio characteristic, but passing ratio selector valve 4 is regulated the input and output flow of hydraulic actuator, as shown in the figure, when proportional reversing valve 4 works in left position, the pressure oil of B mouth is by shuttle valve 5, oil circuit control 05 feeds back to the control port of bi-bit bi-pass pressure difference valve 3, and under the adjusting of pressure difference valve 3, proportional reversing valve 4 front and back are that the pressure reduction between P mouth and the B mouth is constant; When proportional reversing valve 4 works in right position, the pressure oil of A mouth feeds back to the control port of bi-bit bi-pass pressure difference valve 3 by shuttle valve 5, oil circuit control 05, under the adjusting of pressure valve 3, the front and back of proportional reversing valve 4 be P mouth and A mouth between pressure reduction constant, make like this system have fast response time (fretting performance of hydraulic actuator is good), characteristics that control accuracy is high.
When system works in large flow rate working conditions lower time, for example, the required flow of hydraulic actuator is during greater than 40L/min, the spool aperture of control ratio selector valve 4 is excessively to all-round switch, make proportional reversing valve 4 not have the ratio characteristic, at this moment, proportional reversing valve 4 front and back are that pressure reduction will be less than the adjusting pressure of pressure difference valve between P mouth and B mouth or P mouth and the A mouth, it is not output flow of pressure difference valve, can realize adjusting to the hydraulic actuator input flow rate making like this system have the high characteristics of efficient by the controlled variable pump like this.
In above-described embodiment, hydraulic actuator 6 can be the parts that oil hydraulic motor (as shown in the figure) or hydraulic jack etc. are converted into pressure energy mechanical energy.
In above-described embodiment, the separation of flow depends on ratio characteristic and the traffic demand of hydraulic actuator under different operating modes of proportional reversing valve 4, might not be restricted to 40L/min, can also be other values.
In above-described embodiment, proportional reversing valve 4 is three-position four-way valve, in other embodiments, also can adopt as required the selector valve of other types, such as two position two-way valve etc.
In above-described embodiment, by shuttle valve 5 being set with the 3rd oil circuit 03(A mouth) and the 4th oil circuit 04(B mouth) in oil pressure the grater feed back to the control port of pressure difference valve 3 by oil circuit control 05, in other embodiments, also can adopt other modes, if can realize the general wherein oil pressure the grater be introduced into the control port of pressure difference valve 3.
The embodiment of the invention also provides a kind of engineering machinery, such as hoist etc., this project machinery is provided with the hydraulic system of above-described embodiment, because above-mentioned hydraulic system has above-mentioned technique effect, therefore, this project machinery also should possess corresponding technique effect, and the specific implementation process of its appropriate section is similar to the above embodiments, does not hereby give unnecessary details.
The above only is preferred embodiment of the present invention, and is in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of doing, is equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (7)
1. hydraulic system is characterized in that:
Described hydraulic system comprises fuel tank (1), variable displacement pump (2), pressure difference valve (3), proportional reversing valve (4) and hydraulic actuator (6);
The filler opening of described variable displacement pump (2) is connected to fuel tank (1), and the oil outlet of described variable displacement pump (2) is connected to the main filler opening (P) of described proportional reversing valve (4) by the first oil circuit (01);
The main return opening (T) of described proportional reversing valve (4) is connected to fuel tank (1) by the second oil circuit (02), and first actuator port (A) of described proportional reversing valve (4) and the second actuator port (B) are connected to respectively the oil inlet and outlet of described hydraulic actuator (6) by the 3rd oil circuit (03) and the 4th oil circuit (04);
The filler opening of described pressure difference valve (3) is connected to described the first oil circuit (01), the oil outlet of described pressure difference valve (3) is connected to fuel tank (1), the control port of described pressure difference valve (3) is connected to oil circuit control (05), and the pressure oil of described oil circuit control (05) comes from oil pressure the grater of described the 3rd oil circuit (03) and described the 4th oil circuit (04).
2. hydraulic system as claimed in claim 1 is characterized in that:
Described hydraulic system also comprises shuttle valve (5);
Two input ends of described shuttle valve (5) are connected to respectively described the 3rd oil circuit (03) and described the 4th oil circuit (04), and the output terminal of described shuttle valve (4) is connected to described oil circuit control (05).
3. hydraulic system as claimed in claim 1 or 2, it is characterized in that: described proportional reversing valve (4) is electro-hydraulic proportion reversing valve.
4. hydraulic system as claimed in claim 1 or 2, it is characterized in that: described proportional reversing valve (4) is three-position four-way valve, in the first job position, described main filler opening (P) is communicated in described the second actuator port (B), described main return opening (T) is communicated in described the first actuator port (A), in the second working position, described main filler opening (P) disconnects, described main return opening (T) is communicated in described the first actuator port (A) and described the second actuator port (B), in the 3rd working position, described main filler opening (P) is communicated in described the first actuator port (A), and described main return opening (T) is communicated in described the second actuator port (B).
5. hydraulic system as claimed in claim 1 or 2, it is characterized in that: described hydraulic actuator (6) is oil hydraulic motor or hydraulic jack.
6. engineering machinery, it is characterized in that: described engineering machinery is provided with each described hydraulic system of claim 1 to 5.
7. engineering machinery as claimed in claim 6, it is characterized in that: described engineering machinery is hoist.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012103520564A CN102889253A (en) | 2012-09-20 | 2012-09-20 | Hydraulic system and engineering machinery |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012103520564A CN102889253A (en) | 2012-09-20 | 2012-09-20 | Hydraulic system and engineering machinery |
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| CN102889253A true CN102889253A (en) | 2013-01-23 |
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| CN2012103520564A Pending CN102889253A (en) | 2012-09-20 | 2012-09-20 | Hydraulic system and engineering machinery |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105692509A (en) * | 2015-11-10 | 2016-06-22 | 林德（中国）叉车有限公司 | Forklift hydraulic system with dynamic throttling speed governing circuit |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3812728B2 (en) * | 2001-12-13 | 2006-08-23 | 株式会社小松製作所 | Upper revolving work vehicle |
| CN101255879A (en) * | 2007-12-10 | 2008-09-03 | 兰州理工大学 | Steering preference type flux amplification valve |
| CN101260789A (en) * | 2008-04-17 | 2008-09-10 | 中国石油天然气集团公司 | Speed matching control device between continuous tube apparatus infusion head and drum |
| CN201560706U (en) * | 2009-12-23 | 2010-08-25 | 三一重型装备有限公司 | Hydraulic control circuit for rock drill and control system thereof |
| CN102538246A (en) * | 2012-01-10 | 2012-07-04 | 天津市欧曼液压装备系统工程有限公司 | Proportional hydraulic control tracking system for butterfly type solar thermal generating set |
| CN202316710U (en) * | 2011-12-08 | 2012-07-11 | 东莞大同数控机械有限公司 | Servo hydraulic hybrid bender hydraulic system |
| US20120199765A1 (en) * | 2009-10-16 | 2012-08-09 | Philipp Hilzendegen | Valve assembly |
| CN102661296A (en) * | 2012-05-10 | 2012-09-12 | 中联重科股份有限公司 | Hydraulic system and engineering machinery vehicle |
-
2012
- 2012-09-20 CN CN2012103520564A patent/CN102889253A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3812728B2 (en) * | 2001-12-13 | 2006-08-23 | 株式会社小松製作所 | Upper revolving work vehicle |
| CN101255879A (en) * | 2007-12-10 | 2008-09-03 | 兰州理工大学 | Steering preference type flux amplification valve |
| CN101260789A (en) * | 2008-04-17 | 2008-09-10 | 中国石油天然气集团公司 | Speed matching control device between continuous tube apparatus infusion head and drum |
| US20120199765A1 (en) * | 2009-10-16 | 2012-08-09 | Philipp Hilzendegen | Valve assembly |
| CN201560706U (en) * | 2009-12-23 | 2010-08-25 | 三一重型装备有限公司 | Hydraulic control circuit for rock drill and control system thereof |
| CN202316710U (en) * | 2011-12-08 | 2012-07-11 | 东莞大同数控机械有限公司 | Servo hydraulic hybrid bender hydraulic system |
| CN102538246A (en) * | 2012-01-10 | 2012-07-04 | 天津市欧曼液压装备系统工程有限公司 | Proportional hydraulic control tracking system for butterfly type solar thermal generating set |
| CN102661296A (en) * | 2012-05-10 | 2012-09-12 | 中联重科股份有限公司 | Hydraulic system and engineering machinery vehicle |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105692509A (en) * | 2015-11-10 | 2016-06-22 | 林德（中国）叉车有限公司 | Forklift hydraulic system with dynamic throttling speed governing circuit |
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Application publication date: 20130123 |