CN104047931B - Three-way pressure compensating device assembly - Google Patents
Three-way pressure compensating device assembly Download PDFInfo
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- CN104047931B CN104047931B CN201410282011.3A CN201410282011A CN104047931B CN 104047931 B CN104047931 B CN 104047931B CN 201410282011 A CN201410282011 A CN 201410282011A CN 104047931 B CN104047931 B CN 104047931B
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Abstract
A kind of three-way pressure compensating device assembly, three-way pressure compensating utensil has two operating positions, and its spring cavity connects with LS mouth, T mouth through damping network, connects with P mouth through dynamic antivibration hole；One end of damping network connects with T mouth, one end connects with LS mouth through filter；The cavity of resorption of three-way pressure compensating device connects with P mouth through damping hole.It is an advantage of the current invention that to use half-bridge damping network, dynamic antivibration hole, oil-feed to fix damping hole and cooperate, be effectively realized three-way pressure compensating device LS feedback pressure stable, it is ensured that its valve core movement is steady, thus realize stable shunting；Effectively eliminate the peak value of load pressure fluctuation, reduce pressure gain, it is ensured that each executor is stable；Quantitative load sensitive system is made to realize the function of " high-pressure low-flow, low pressure and mass flow ".
Description
Technical field
The present invention relates to a kind of three-way pressure compensating device.Particularly to wheel loader, crane, the three-way pressure compensating device assembly of the engineering machinery load sensory system such as mini-excavator.
Background technology
Quantitatively load sensitive system is widely used in loader because of energy-conservation and low cost, the engineering machinery such as autocrane and mini-excavator.Load-sensitive multiple directional control valve is the core parts of such load sensitive system, and quantitatively load sensitive system executive component to be realized flow distribution according to need, three-way pressure compensating device is the requisite element of such hydraulic control system.Three-way pressure compensating device is utilized to cooperate with load sensing multi-way valve, so that load sensitive system realizes the function of " high-pressure low-flow; low pressure and mass flow ", that is: when executive component starts, main pump provides high pressure to load, make executive component overcome frictional force and it needs to low discharge prevents main overflow valve overflow, save energy loss, prevent system heat generation；When executive component overcomes stiction to turn to kinetic force of friction, main pump provides less pressure to overcome kinetic force of friction to load, and provides a system to big flow and forces executor's accelerated motion, improves executor's work efficiency.
The most just all there is pressure shake in various degree at widely used quantitative load sensitive system for current, this, to the strict crane work system of micro-control performance requirement, is not allowed to, it is therefore desirable to take correlation method to solve.Its quantitative load sensitive system produces the reason of pressure shake and is that the P mouth pressure of three-way pressure compensating device feeds back to the lower end of its valve rod through damping hole, and LS mouth pressure feeds back to the spring cavity of three-way pressure compensating device through damping hole.But need mating in view of pilot handle and main control valve owing to quantitative load sensitive system realizes flow, main control valve mates with three-way pressure compensating device, unreasonable three-way pressure compensating device bumpy motion will necessarily be made if mating, and cause system pressure fluctuation bigger, thus cause executive component to be shaken, have a strong impact on the service behaviour of main frame.
Summary of the invention
It is an object of the invention to provide a kind of LS feedback pressure that eliminates to fluctuate so that three-way pressure compensating device stably opens and closes, thus realizes load sensitive system and stably shunt, and eliminates the three-way pressure compensating device assembly of the problems such as executor's shake.
The solution of the present invention is such that
A kind of three-way pressure compensating device assembly, this assembly includes T mouth, LS mouth and P mouth, it is connected between T mouth with LS mouth and has LS overflow valve, it is connected between T mouth with LS mouth and has constant flow valve, being connected between P mouth with T mouth and have three-way pressure compensating device, described three-way pressure compensating utensil has two operating positions, when three-way pressure compensating device is operated in right position, the working hole direct T mouth oil sump tank of three-way pressure compensating device, the whole oil sump tank of fluid of hydraulic system；When three-way pressure compensating device is operated in left position, three-way pressure compensating device oil return opening is closed, and P mouth disconnects with T mouth, and hydraulic system is to executive component fuel feeding；The spring cavity of described three-way pressure compensating device connects with T mouth through damping network, and the spring cavity of three-way pressure compensating device connects with LS mouth with filter through damping network, described damping network includes check valve, the first damping hole, the second damping hole, the 3rd damping hole；Described damping network connects with spring cavity, LS mouth and the T mouth of three-way pressure compensating device simultaneously.
Further: described check valve has three junction points, it may be assumed that the first junction point is connected with LS mouth through the first damping hole, filter；Second junction point connects with T mouth through the second damping hole；3rd junction point connects with the spring cavity of three-way pressure compensating device.
Further: described check valve is composed in parallel one-way damper valve by check valve and the 3rd damping hole；
Further: described 3rd damping hole is the damping hole including using the series connection of at least two damping hole to be formed；
Further: the control chamber of described three-way pressure compensating device is connected with oil-feed damping hole and is followed by P mouth；The spring cavity of described three-way pressure compensating device connects with P mouth through dynamic antivibration hole, and the function of dynamic antivibration is played in dynamic antivibration hole.
The invention have the advantage that
1, use fixing damping hole to form half-bridge damping network, effectively the control cavity pressure of three-way pressure compensating device is filtered, it is ensured that LS pressure controling signal is steady, without bigger pressure fluctuation；
2, use half-bridge damping network, dynamic antivibration hole, oil-feed to fix damping hole and cooperate, be effectively realized three-way pressure compensating device LS feedback pressure stable, it is ensured that its valve core movement is steady, thus realize stable shunting；
3, effectively eliminate the peak value of load pressure fluctuation, reduce pressure gain, reduce dosing pump import and executive component input pressure and flow pulsation, it is ensured that each executor is stable；
4, quantitative load sensitive system is made to realize the function of " high-pressure low-flow, low pressure and mass flow ".
Accompanying drawing explanation
Fig. 1 is the hydraulic schematic that the three-way pressure compensating device assembly of the present invention is applied to the quantitative load sensitive system that downstream pressure compensates.
Fig. 2 is the hydraulic schematic that the three-way pressure compensating device assembly of the present invention is applied to the quantitative load sensitive system that upstream pressure compensates.
Fig. 3 is the hydraulic schematic diagram of the embodiment of the present invention one.
Fig. 4 is the hydraulic schematic diagram of the embodiment of the present invention two.
In figure: 1, hydraulic oil container；2, dosing pump；3, three-way pressure compensating device assembly；4-1, there is the load sensing multi-way valve of valve post-compensation；4-2, there is the load sensing multi-way valve of valve precompensation；5, executive component；31, LS overflow valve；32, filter；33, damping network；34, dynamic antivibration hole；35, oil-feed damping hole；36, three-way pressure compensating device；37, constant flow valve.
Detailed description of the invention
The hydraulic schematic diagram of the present invention is as shown in Figure 3, in three-way pressure compensating device assembly hydraulic system shown in Fig. 3, including LS overflow valve 31, filter 32, damping network 33, dynamic antivibration hole 34, oil-feed damping hole 35, three-way pressure compensating device 36 and constant flow valve 37, the hydraulic schematic diagram connection as shown in Figure 3 of above-mentioned hydraulic unit collectively forms three-way pressure compensating device assembly.
T mouth, LS mouth and P mouth is included according to the three-way pressure compensating device assembly that hydraulic schematic diagram shown in Fig. 3 is made, it is connected between T mouth with LS mouth and has LS overflow valve 31, it is connected between T mouth with LS mouth and has constant flow valve 37, it is connected between P mouth with T mouth and has three-way pressure compensating device 36, described three-way pressure compensating device 36 has two operating positions, when three-way pressure compensating device is operated in right position, the working hole direct T mouth oil sump tank of three-way pressure compensating device 36, the whole oil sump tank of fluid of hydraulic system；When three-way pressure compensating device 36 is operated in left position, three-way pressure compensating device oil return opening is closed, and P mouth disconnects with T mouth, and hydraulic system is to executive component fuel feeding；
The spring cavity of described three-way pressure compensating device connects with LS, T mouth through damping network 33, filter 32.
As shown in Figure 4: damping network includes check valve, the first damping hole d1, the second damping hole d2, the 3rd damping hole d3；And connect with spring cavity, LS mouth and the T mouth of three-way pressure compensating device simultaneously；
Check valve has three junction points, it may be assumed that the first junction point is connected with LS mouth through the first damping hole d1, filter；Second junction point connects through the second damping hole d2 and T mouth；3rd junction point connects with the spring cavity of three-way pressure compensating device.
As shown in Figure 4, check valve and the 3rd damping hole d3 one-way damper valve is composed in parallel；Wherein the 3rd damping hole d3 is the structure that the damping hole using two damping hole d3-1 and d3-2 series connection to be formed realizes, and such as the structure of Fig. 3, certainly, the 3rd damping hole d3 can also use three, four or more damping hole series connection to realize.；
Such as Fig. 3, the cavity of resorption of three-way pressure compensating device connects with P mouth through oil-feed damping hole 35, and the spring cavity of three-way pressure compensating device connects with P mouth through dynamic antivibration hole 34.
When the present invention is applied to Fig. 1, system shown in 2, LS overflow valve 31, the drainback passage of the outlet of three-way pressure compensating device 36 and constant flow valve 37 and the load sensing multi-way valve 4-1 with valve post-compensation or the load sensing multi-way valve 4-2 with valve precompensation connects, and returns hydraulic oil container through oil return inlet T mouth；The LS pressure feedback channel of LS overflow valve 31, the import of constant flow valve 37 and filter 32 and the load sensing multi-way valve 4-1 with valve post-compensation or the load sensing multi-way valve 4-2 with valve precompensation connects；The oil-in of the oil inlet P of three-way pressure compensating device 36 and the load sensing multi-way valve 4-1 with valve post-compensation or the load sensing multi-way valve 4-2 with valve precompensation connects, and forms bypass speed control loop；The oil-in of three-way pressure compensating device 36 spring cavity through dynamic antivibration hole 34 with three-way pressure compensating device 36 connects, the effect of dynamic antivibration is played in dynamic antivibration hole 34, the LS pressure feedback signal of the load sensing multi-way valve 4-1 with valve the post-compensation as shown in Figure 1, 2 or load sensing multi-way valve 4-2 with valve precompensation is applied to the spring cavity of three-way pressure compensating device through filter 32, damping network 33；It is filtered processing with dynamic antivibration hole 34 also LS pressure signal or load signal by damping network 33, efficiently solve the problem causing executive component to shake relatively greatly because of the pressure oscillation that load movement impacts or reversal valve area of passage variable gradient causes more greatly that quantitative load sensitive system exists, thus improve the service behaviour of quantitative load sensitive system.
Damping network 33 described above is as it is shown on figure 3, include one-way damper valve, damping hole d1, damping hole d2, and damping network connects with spring cavity, T mouth and the LS mouth of three-way pressure compensating device simultaneously.
First damping hole d1 is that the import of damping network, the second damping hole d2 and T mouth connect, the half-bridge damping network formed by the first damping hole d1, the second damping hole d2, effectively LS pressure is filtered, thus ensure that the LS pressure signal entering three-way pressure compensating device spring cavity is stable, fluctuate less.
nullSteady in order to further ensure the LS pressure signal entering three-way pressure compensating device spring cavity，Therefore at three-way pressure compensating device spring cavity series connection one-way damper valve，Wherein one-way damper valve is by check valve (check)、3rd damping hole d3 composition，And the 3rd Buddhist nun hole d3 is by two damping hole damping hole d3-1、D3-2 is in series，Have an advantage in that building pressure so that three-way pressure compensating device 36 spring cavity damps different with release，I.e. build and press through journey only one of which the first damping hole d1 and be connected on loop，Damping action is little，Pressure leak process is through the first damping hole d1、Form two damping hole d3-1 of the 3rd damping hole、d3-2，Damping action is bigger，Effectively reduce three-way pressure compensating device 36 two ends pressure reduction change amplitude，Make three-way pressure compensating device 36 valve core movement mild，Eliminate the peak value of load pressure fluctuation further，Reduce pressure gain，Reduce dosing pump import and executive component input pressure、Flow pulsation，Thus the problem solving the pressure shake that quantitative load sensitive system occurs when minute opening opens and closes.
In Fig. 1, system shown in 2, being quantitative load sensitive system, difference is the difference of load sensing multi-way valve, and the load-sensitive valve of Fig. 1 is the load-sensitive valve that downstream pressure compensates, and the load-sensitive valve of Fig. 2 is the load-sensitive valve that upstream pressure compensates.
In Fig. 1, the quantitative load sensitive system shown in 2, including hydraulic oil container, dosing pump 2, three-way pressure compensating device assembly 3, there is the load sensing multi-way valve 4-1 of valve post-compensation or there is the load sensing multi-way valve 4-2 of valve precompensation, executive component 5 main functional component such as grade.The wherein P mouth of dosing pump 2 and three-way pressure compensating device assembly 3, the oil inlet P mouth connection of the load sensing multi-way valve 4-1 with valve post-compensation or the load sensing multi-way valve 4-2 with valve precompensation；The T mouth of the load sensing multi-way valve 4-1 with valve post-compensation or the load sensing multi-way valve 4-2 with valve precompensation connects with hydraulic oil container with the drain tap of dosing pump；This has the load sensing multi-way valve 4-1 of valve post-compensation or has each connection hydraulic fluid port A1 and B1, A2 and the B2 of load sensing multi-way valve 4-2 of valve precompensation, A3 and B3 connects with corresponding executive component respectively, such as hydraulic jack and hydraulic motor；Pilot control oil circuit is a1 and b1, a2 and b2, a3 and b3.Load sensing multi-way valve and the connection of each executive component, the load-sensitive valve that downstream pressure compensates, the load-sensitive valve that upstream pressure compensates is same as the prior art, therefore the hydraulic schematic diagram of Fig. 1 and Fig. 2 is shown specifically, to simplify accompanying drawing.Accordingly it is also possible to understand, those skilled in the art can be fully achieved based on prior art, therefore the most no longer describe in detail.
The load sensing multi-way valve 4-1 with valve post-compensation or the load sensing multi-way valve 4-2 with valve precompensation has LS load pressure feedback ports, LS pressure is each executor's maximum load, LS pressure feedback mouth connects with the LS mouth of three-way pressure compensating device assembly 3, in real time load signal is fed back to the spring cavity of three-way pressure compensating device 36, to control the aperture of three-way pressure compensating device 36, realize dosing pump by load necessary flow fuel feeding, to reduce the pressure flow loss of executor to greatest extent, reach the effect of Energy Saving Control.
Load-sensitive valve valve connection quantity described above more than the most described 3, the valve connection quantity of load sensing multi-way valve can be as desired to determine.
The above is only the preferred embodiment of the present invention; it should be pointed out that, for those skilled in the art, under the premise without departing from the principles of the invention; can also make some improvements and modifications, these improvements and modifications also should be regarded as protection scope of the present invention.
Claims (4)
1. a three-way pressure compensating device assembly, this assembly includes T mouth, LS mouth and P mouth, it is connected between T mouth with LS mouth and has LS overflow valve (31), it is connected between T mouth with LS mouth and has constant flow valve (37), it is connected between P mouth with T mouth and has three-way pressure compensating device (36), described three-way pressure compensating device (36) has two operating positions, when three-way pressure compensating device is operated in right position, the working hole direct T mouth oil sump tank of three-way pressure compensating device (36), the whole oil sump tank of fluid of hydraulic system；When three-way pressure compensating device (36) is operated in left position, three-way pressure compensating device oil return opening is closed, and P mouth disconnects with T mouth, and hydraulic system is to executive component fuel feeding；The spring cavity of described three-way pressure compensating device connects with T mouth through damping network (33), and the spring cavity of three-way pressure compensating device connects with LS mouth with filter (32) through damping network (33), it is characterised in that: described damping network is made up of check valve (check), the first damping hole (d1), the second damping hole (d2) and the 3rd damping hole (d3)；And damping network connects with spring cavity, LS mouth and the T mouth of three-way pressure compensating device simultaneously.
Three-way pressure compensating device assembly the most according to claim 1, it is characterised in that: described check valve has three junction points, it may be assumed that the first junction point is connected with LS mouth through the first damping hole (d1), filter；Second junction point connects with T mouth through the second damping hole (d2)；3rd junction point connects with the spring cavity of three-way pressure compensating device.
Three-way pressure compensating device assembly the most according to claim 1 and 2, it is characterised in that: described check valve (check) and the 3rd damping hole (d3) compose in parallel one-way damper valve.
Three-way pressure compensating device assembly the most according to claim 1, it is characterised in that: described 3rd damping hole (d3) includes the damping hole using the series connection of at least two damping hole to be formed.
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| CN201410282011.3A CN104047931B (en) | 2014-06-23 | 2014-06-23 | Three-way pressure compensating device assembly |
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| CN201410282011.3A CN104047931B (en) | 2014-06-23 | 2014-06-23 | Three-way pressure compensating device assembly |
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| CN104047931B true CN104047931B (en) | 2017-01-04 |
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| CN104728196B (en) * | 2015-03-18 | 2017-08-25 | 北京航空航天大学 | The Electrical hydrostatic actuator of load-sensitive |
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| CN104819176B (en) * | 2015-03-18 | 2017-06-20 | 北京航空航天大学 | The Electrical hydrostatic actuator of the load-sensitive based on switch valve and hydraulic control one-way valve |
| CN107781251B (en) * | 2016-08-26 | 2023-12-22 | 徐州徐工筑路机械有限公司 | Multi-way valve, hydraulic system and land leveler |
| CN107725523B (en) * | 2017-11-14 | 2023-12-15 | 江苏恒立液压科技有限公司 | Load-sensitive multiway valve and engineering machinery with same |
| CN107762999B (en) * | 2017-11-23 | 2019-05-24 | 李群 | Three-way pressure compensating valve and pressure compensating system |
| CN108240366B (en) * | 2018-01-25 | 2019-07-26 | 凯文斯流体控制(江苏)有限公司 | A kind of flow divider valve for the hydraulic accessory of excavator |
| CN109630504B (en) * | 2018-12-26 | 2021-01-26 | 太原理工大学 | Oil inlet and outlet independent control system with pressure compensation function |
| CN109899329B (en) * | 2019-03-29 | 2021-05-18 | 潍柴动力股份有限公司 | Load sensitive control mechanism and hydraulic system |
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Effective date of registration: 20230424 Address after: 545000 No. 6, Yangtai Road, Yanghe industrial new area, Liuzhou City, Guangxi Zhuang Autonomous Region Patentee after: Guangxi Zhongyuan Machinery Co.,Ltd. Patentee after: ANHUI LIUGONG CRANE Co.,Ltd. Patentee after: GUANGXI LIUGONG MACHINERY Co.,Ltd. Address before: 545006 Yanghe North Road, Yanghe Industrial Zone, Liuzhou, the Guangxi Zhuang Autonomous Region, B-14-1 Patentee before: LIUZHOU LIUGONG HYDRAULIC COMPONENTS Co.,Ltd. Patentee before: ANHUI LIUGONG CRANE Co.,Ltd. Patentee before: GUANGXI LIUGONG MACHINERY Co.,Ltd. |