CN202851491U - Load-sensitive multi-way valve used in loader variable system - Google Patents

Load-sensitive multi-way valve used in loader variable system Download PDF

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Publication number
CN202851491U
CN202851491U CN 201220478690 CN201220478690U CN202851491U CN 202851491 U CN202851491 U CN 202851491U CN 201220478690 CN201220478690 CN 201220478690 CN 201220478690 U CN201220478690 U CN 201220478690U CN 202851491 U CN202851491 U CN 202851491U
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valve
pressure
way valve
variable system
load
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CN 201220478690
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池建伟
蔡铮
潘承乾
蒋俊
陈学才
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ZHEJIANG GAOYU HYDRAULIC MECHANICAL AND ELECTRICAL CO Ltd
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ZHEJIANG GAOYU HYDRAULIC MECHANICAL AND ELECTRICAL CO Ltd
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Abstract

The utility model discloses a load-sensitive multi-way valve used in a loader variable system. The load-sensitive multi-way valve comprises an oil inlet and return part (31), a bucket part (32), a movable arm part (33), and an additional function part (34), wherein the movable arm part (33) or the bucket part (32) comprises a valve body (1), a related oil way, a reversing valve rod (5) and a pressure compensator (19), the reversing valve rod (5) and the pressure compensator (19) are arranged in the valve body (1), a plurality of round throttling grooves (8) are arranged in the reversing valve rod (5), and the reversing valve rod (5) is distributed between cavities of the valve body (1). According to the load-sensitive multi-way valve used in the loader variable system, output flow quantity of the multi-way reversing valve can be matched with a spool stroke, micro control performance is good, the speed of actuators is not related to load pressure, flow quantity pressure does not influence each other when a plurality of the actuators moves in a compound mode, and flow quantity leading to the actuators can still maintain proportional relation even the flow quantity is saturated.

Description

The load sensing multi-way valve that is used for the loader variable system
Technical field
The utility model relates to the hydraulic components of construction machinery technical field, is specifically related to a kind of precompression valve, the regeneration Fill valve, and guide's delivery valve reaches the loader load sensing multi-way valve that multiple directional control valve is integrated in one.
Background technique
Now widely used loader hydraulic system all adopts traditional multiple directional control valve, and is most for blocking special multi-way valve D32.The type multiple directional control valve belongs to the traditional center of opening throttle valve, its control starting point is relevant with the variation of load with speed adjustable range, influence each other between the operation mechanism of working simultaneously, the mechanism speed that has higher load when two above loads are worked simultaneously may diminish even be motionless.The operating rate of actuator and the stroke of multi-way valve change can't form coupling, makes the operator form anticipation to carrying out machine work speed, and manoeuvring performance is not good.Technical ability to the operator during work has certain requirement.Logical throttling road causes power loss in the spool, and particularly loss is larger when the high pressure cutting condition.Use the load sensing multi-way valve of valve precompensation, can address the above problem.But when the selector valve stroke increases, when the traffic demand sum of each actuator surpasses the maximum output flow of pump (saturated hereinafter referred to as flow), the flow of valve precompensation load sensitive system will preferentially satisfy the low-pressure load, and the flow of high capacity actuator will reduce even stop.Cause thus actuator's working stability, harmony and reliability can not ensure.
Loader actuator is comprised of swing arm and scraper bowl, supports the oil hydraulic cylinder of these mechanisms, not only will bear the deadweight of actuating mechanism, also will support scraper bowl institute bringing onto load.In order to prevent stall, traditional method is that the oil return side valve bar at multi-way valve arranges throttling groove.When turning under the scraper bowl or swing arm when descending, it is very high that the load on the scraper bowl will make the back oil cavity pressure of oil cylinder rise to.Converting heat to when like this, the high pressure fluid of oil back chamber formation is by the throttling groove oil sump tank runs off.Simultaneously, transfer meeting fast so that the oil cylinder oil inlet cavity pressure reduces, even negative pressure occurs, cavitation phenomenon occurs, the infringement hydraulic element reduce its working life.
The model utility content
The novel purpose of this example is the above-mentioned technical problem that exists in the loader hydraulic system for prior art, a kind of multiple directional control valve is provided, multiple directional control valve output flow and spool stroke are complementary, has good micro-control performance, actuator's speed and induced pressure are irrelevant, and during a plurality of actuators composite moves, flow pressure is independent of each other, even when flow is saturated, still can allows and keep proportionate relationship towards the flow of each actuator.Under the specific operation, oil cylinder oil back chamber hydraulic oil can be realized oil return regeneration for being back to the oil cylinder oil inlet chamber, saves energy, and prevents cavitation erosion.
For achieving the above object, the utility model provides a kind of load sensing multi-way valve for the loader variable system, comprise: oil inlet and oil return section, scraper bowl section, swing arm section, additional function section, described swing arm section or scraper bowl section comprise valve body and relevant oil duct and are positioned at commutation valve rod, the pressure compensator of described valve body.
Further, on the described commutation valve rod a plurality of circular throttling grooves are arranged.
Further, described commutation valve rod is arranged between each cavity of described valve body.
Further, described pressure compensator is inserted on the middle mounting hole of described valve body, between the pressure compensator ante-chamber and first, second cavity of valve body.
Further, described pressure compensator has compensating spool, selects spring, Returnning spring and selection spool, and the part of described selection spool is positioned at compensating spool.
Further, on the described pressure compensator mouthful is the LS hydraulic fluid port, communicates with LS chamber on the valve body plug-in opening.
Further, also comprise regeneration function section, comprising: precompression valve and regeneration Fill valve.
Further, described swing arm section or scraper bowl section also comprise overload valve and regeneration Fill valve.
Further, described additional function section comprises: LS relief valve, LS unloading valve and guide's delivery valve
Oil inlet P is communicated to the oil suction chamber (selector valve throttling groove ante-chamber) of scraper bowl and swing arm section by inner oil duct.Be provided with the pressure compensator with pressure compensation and load maintenance effect behind the inherent commutation of each the commutation connection valve rod throttling groove.The LS pressure port is arranged at this pressure compensator top, communicate with the LS passage on the valve body plug-in opening, the LS chamber passing hole channel of two commutation valve bodies is connected, and extend to LS relief valve and the LS unloading valve of additional valve section, with the LS valve seat, by the road LS pressure is received again on the LS pressure feedback mouth of load sensitive pump.The effect of variable displacement pump is that to make the difference of the oil liquid pressure of output and LS feedback port pressure be definite value.Thereby so that the definite value of the output flow of valve for being directly proportional with the throttling groove opening area.
Pressure compensator has induced pressure and selects and compensate function, actuator's highest load pressure that it will be worked is simultaneously chosen the LS oil duct, simultaneously this LS pressure is delivered to pressure compensator spring sensitive cavity, this pressure pilot pressure compensator opening is so that cavity pressure equals LS pressure before the compensator.So that cavity pressure all equals LS pressure behind the valve rod throttling groove of all Reversing valve plates.And cavity pressure equals pump intake pressure P before all valve rods.Aforementioned variable displacement pump can make the difference of P and LS constant.So all valve rod pressure reduction equate, flow only is directly proportional with area separately.The flow of each plate valve and its separately opening area are proportional.When induced pressure was higher than pump intake pressure, the pressure compensator autoshutdown realized that load keeps function.
Be provided with precompression valve between the back oil road T1 of the B actuator port of each commutation connection and the back oil road T of multi-way valve, make the working hole oil return keep fixing back pressure.When scraper bowl and swing arm are transferred, the oil-feed of A mouth, the oil return of B mouth is pushed precompression valve open to the T1 mouth and is got back to the T mouth and flow back to fuel tank.When because load weight, so that upper cavity pressure is when being lower than precompression valve pressure, the oil of T1 will be opened one-way valve for being back to the A chamber, realize oil return regeneration.
The utility model additional valve section comprises the delivery valve that pilot pressure oil is provided, and limits the overload valve of LS pressure and keeps the LS unloading valve of pressure compensator flexible motion.
Description of drawings
Fig. 1 is hydraulic principle schematic representation of the present utility model.
Fig. 2 is swing arm valve block sectional view of the present utility model.
Fig. 3, Fig. 4 are the utility model pressure compensator sectional view.
Fig. 5 is regeneration function of the present utility model section sectional view.
Fig. 6 is the hydraulic system schematic representation that the utility model is implemented.
Embodiment
Below in conjunction with accompanying drawing the utility model is further described.
See also Fig. 1-Fig. 5 its implementation process be described:
As shown in Figure 1, the load sensing multi-way valve for the loader variable system of the present utility model comprises oil inlet and oil return section 31, scraper bowl section 32, swing arm section 33, additional function section 34 and each actuator port.The valve arrangement of scraper bowl section 32 and swing arm section 33 is basically identical.
Oil-feed section is provided with precompression valve 1.1 and safety valve 1.2.
Swing arm section 33 comprises valve rod 3.4, pressure compensator 3.5, regeneration one-way valve 3.2, overload valve 3.3.
Additional function section comprises LS relief valve 4.1, LS unloading valve 4.2, LS pressure valve seat 4.3, guide's hydraulic fluid port 4.4, guide's delivery valve 4.5.LS relief valve 4.1 restriction LS oil circuit pressure, protective system prevents overload.LS unloading valve 4.2 makes LS channel pressure oil unload oil sump tank with constant flow, and it can make the off-load of LS oil duct when meta, when commutation work, can play the effect of pilot pressure compensating spool motion.Guide's delivery valve can make equipment such as saving a pioneer pump and associated pipe in the loader hydraulic system for the hydraulic control handle of multi-way valve provides pressure source.
Each actuator port is that flange connects, and each additional valve is threaded connection and is inserted on the valve body.
As shown in Figure 2, the swing arm connection comprises valve body 1 and relevant oil duct, actuator port, moving arm valve pole 5, control end cover 13 and 22, pressure compensator 19, and overload valve and plug.The A active chamber is provided with the regeneration Fill valve, will be in aftermentioned.As shown in Figure 2, a lot of circular throttling grooves 8 are arranged on the moving arm valve pole 5, be arranged between valve body 1 each cavity.Valve body 1 upper cavity 9 is pump oil suction chamber (throttling groove 8 ante-chambers), cavity 7 is pressure compensator ante-chamber (throttling groove 8 back cavities), cavity 6 logical oil back chambers, and moving arm valve pole 5 is when meta, the pressure compensator cavity of resorption communicates with cavity 6, and pressure compensator can be resetted under action of reset spring.Pressure compensator 19 is inserted on the middle mounting hole of commutation valve body, is arranged between cavity 7 and the cavity 15,20.When the pressure compensation spool was opened, cavity 7 fluid were communicated with cavity 15,20 by hole 16.Mouth 18 on the pressure compensator communicates with LS chamber 17 on the valve body plug-in opening for the LS hydraulic fluid port, and the commutate LS chamber of valve body of LS chamber 17 and another sheet communicates and leads on the LS valve seat of appendix, feeds back to variable displacement pump.Be provided with moving arm valve pole oil sealing shoulder between cavity 15 and the working hole (B) 14, be separated with moving arm valve pole oil sealing shoulder between cavity 20 and the working hole (A) 21.Cavity (T1) 14, oil back chamber 12 is provided with the moving arm valve pole shoulder between cavity 21 and the oil back chamber (T) 3.
As shown in Figure 3, pressure compensator comprises the duct of valve pocket 42 and upper processing thereof, and spool 44 and upper duct thereof are selected in the duct of compensating spool 43 and upper processing thereof, select spring 47, the spring seat on the compensating spool and plug screw, Returnning spring 48, feedback valve plug screw.Auxiliary hole on the compensating spool 43 is with rise formula plug sealing of ball.Compensating spool 43 can in valve pocket 42 interior motions, controlled the opening area of throttling groove 54 according to the front and back cavity pressure.Select spool 44 in compensating spool 43 interior motions, controlling the selection of LS pressure.
As shown in Figure 5, regeneration function section comprises back oil road (T1) 61, precompression valve 65, and back oil road (T) 64, regeneration Fill valve 67 and oil duct 70, oil duct 70 communicates with working hole (A) chamber.
Working principle of the present utility model is:
The neutral position: the P mouth links to each other with the variable displacement pump oil outlet, when each commutation valve rod is in the neutral position, and fluid passive arm valve rod 5 blocking-up between each chamber on the selector valve.At this moment, pressure compensator is not selected pressure to the LS road, and under the effect of LS unloading valve, the LS channel pressure is 0.At this moment the pressure that feeds back to pump is 0.The variable displacement pump delivery pressure is that this pressure of the following supposition of setting pressure reduction △ P(of pump is 1.6MPa), only output remedies a small amount of flow of leakage.
Commutation position:
As shown in Figure 2, when moving arm valve pole 5 moved to left, throttling groove 8 was opened, and fluid flows into cavity 7 from cavity 9 through throttling groove 8, arrives the ante-chamber 41 of the described compensating spool 43 of Fig. 3.Simultaneously, between the active chamber 14 and 15 on the moving arm valve pole 5 throttling groove open, working hole (B) 14 communicates with cavity (15), there is load in working hole (B) chamber, pressure is delivered to the cavity 53 of pressure compensator shown in Figure 3,52 pass to selection spool 44 cavity of resorptions through the hole, promote to select spool 44 to be in upper, and induced pressure passed to compensating spool 43 epicoeles by hole 50, the hole 56 of cavity 7 pressure pressure compensator in pressure compensator hole 55 and Fig. 4 of selector valve is delivered to the LS passage of cavity 17 simultaneously, feed back to variable displacement pump, variable displacement pump pressure is raise.When system pressure was lower than load cavity B pressure, compensating spool 43 failed to open, and this moment, compensating spool 43 played the one-way valve effect.When variable displacement pump boosts to system to be higher than load B cavity pressure, move to the maximum open position on the compensating spool 43, open throttling groove 54, fluid enters cavity 15 through throttling groove 54, enter again the cavity of working hole (B) 14, arrive operation mechanism through working hole (B) 14, drive loaded work piece.The pressure that feeds back to pump LS mouth is the pressure of throttling groove 8 back cavities 7, and variable displacement pump is so that the high fixedly difference △ P(supposition of throttling groove ante-chamber 9 pressure ratio LS pressure 1.6MPa), that is to say that throttling groove 8 front and back pressure reduction are definite value.Also just so that the flow that passes through only with throttling groove area of passage ratio.Also just so that flow and induced pressure are irrelevant, only be directly proportional with the valve core opening area.And spool is once manufacturing and designing, and area and stroke characteristic just are fixed up.That is to say that flow and stroke obtain one-to-one relationship, namely operation has anticipation.
Composite move:
Aforementioned when only having the commutation of swing arm connection valve situation, the situation when the below discusses multi-joint composite move.Described swing arm connection load and commutation valve rod invariant position above keeping.Suppose that scraper bowl connection induced pressure is lower than the swing arm connection.When scraper bowl connection valve rod moves to left, same as above, the fuel-displaced actuator that leads to of the working hole (B) of scraper bowl connection, actuator's oil return is through working hole (A) oil sump tank.This moment, the selection spool cavity of resorption pressure of scraper bowl connection pressure compensator was the scraper bowl load, was lower than LS channel pressure (swing arm load), selected spool to be in initial position and failed to open.Feeding back to compensating spool spring chamber pressure is LS pressure The pressure compensation spool exists Under the pressure-acting, compensating spool is in throttle, so that cavity pressure is increased to LS pressure under the compensating spool, compensating spool is in the equilibrium position.It is swing arm connection induced pressure that the pressure that is to say throttling groove 8 back cavities 7 on the scraper bowl valve rod equals LS pressure.That is to say that swing arm and scraper bowl valve rod throttling groove 8 front and back cavity pressures equate.Thereby the flow that passes through is only proportional with the opening area of throttling groove separately.
When scraper bowl connection pressure is elevated to above swing arm connection induced pressure, this moment, the cavity of resorption active force was selected to move on the spool greater than the epicoele active force for the selection spool of scraper bowl connection compensator, make its load cavity 15 pressure lead to its pressure compensation spool spring chamber, cavity 41 pressure selections enter the LS passage simultaneously.Select spool then just opposite for the swing arm connection, the swing arm connection selects spool to move down into initial position, closes the passage of LS and cavity 1, opens the passage that LS pressure is delivered to spring chamber, make new LS pressure (scraper bowl induced pressure) act on spring chamber, make cavity 41 pressure equal LS pressure.So LS pressure has been finished replacement, LS pressure equals the maximum load pressure of any time.
During the flow undersaturation:
Two when working simultaneously, and as distributing by setting pressure reduction △ P, the required flow sum of load surpasses the peak rate of flow that pump can provide.It is saturated that be called flow this moment.This moment, variable displacement pump was in maximum pump discharge, but can't keep valve rod throttling groove front and back △ P.And for the selector valve pressure compensator no matter whether saturated its managed LS pressure to flow all the time is highest load pressure, keep a few plate valve throttling grooves of working simultaneously before and after pressure reduction equate.Thereby the flow proportional of each sheet relation still be the ratio of opening area, and just throttling groove pressure reduction will be less than setting △ P this moment.That is to say that the utility model valve group has anti-current amount saturated characteristic, even when flow system flow is not enough, still can keep the ratio characteristic.
Regeneration function:
As shown in Figure 2, commutator segment A mouth communicates with one-way valve back cavity oil duct 70 shown in Figure 5, and selector valve 12 chamber T1 oil back chambers link to each other with oil duct 61 shown in Figure 5.Be provided with precompression valve (setting pressure 0.65-0.8MPa) between T1 mouth and the T mouth, the oil return of T1 mouth has constant backpressure when the oil return of T mouth.When load weight was lighter, the A cavity pressure was higher than precompression valve pressure, and namely the chamber pressure of oil duct 70 is greater than the chamber pressure of oil duct 61, and one-way valve oppositely ends.When load is heavier, under load and above-mentioned factor effect, A cavity pressure step-down is in the B cavity pressure, until be lower than precompression valve pressure, this moment, oil duct cavity 70 pressure were lower than oil duct cavity 61 pressure, one-way valve opens, oil duct cavity 61 fluid are pushed one-way valve open and are entered the A chamber, realize regeneration, accelerate cylinder movement speed, make oil return utilized.
The utility model is compared with original loader valve, has the following advantages:
Proportional control: flow is corresponding with the spool stroke relation, and operation mechanism's speed is not subjected to load effect, and speed adjustable range is wide, and the worker handles simply, and is comfortable.
Energy-conservation: POF distribution according to need, pressure and adaptive load.And traditional quantitative system pump full flow output, unnecessary fluid flows back to fuel tank with safety valve pressure during overflow, and energy loss is large, and especially in the little opening throttling of spool, during high-pressure low-flow, loss is maximum.And this model utility hydraulic system, the pump delivery pressure is only than the high △ P value of load, and output flow only determines according to guiding valve throttling groove opening, without unnecessary output.Have the oil return regeneration function, when oil cylinder is transferred, the oil return recycling is saved energy consumption.Integrated pilot control is saved cost, and system is simplified.

Claims (9)

1. load sensing multi-way valve that is used for the loader variable system, comprise: oil inlet and oil return section (31), scraper bowl section (32), swing arm section (33), additional function section (34) is characterized in that: described swing arm section (33) or scraper bowl section (32) comprise valve body (1) and relevant oil duct and are positioned at commutation valve rod (5), the pressure compensator (19) of described valve body (1).
2. the load sensing multi-way valve for the loader variable system as claimed in claim 1 is characterized in that: a plurality of circular throttling grooves (8) are arranged on the described commutation valve rod (5).
3. the load sensing multi-way valve for the loader variable system as claimed in claim 1 or 2, it is characterized in that: described commutation valve rod (5) is arranged between each cavity of described valve body (1).
4. the load sensing multi-way valve for the loader variable system as claimed in claim 1 or 2, it is characterized in that: described pressure compensator (19) is inserted on the middle mounting hole of described valve body (1), between the pressure compensator ante-chamber (7) and first, second cavity (15,20) of valve body (1).
5. the load sensing multi-way valve for the loader variable system as claimed in claim 1 or 2, it is characterized in that: described pressure compensator (19) has compensating spool (43), selection spring (47), Returnning spring (48) and selects spool (44), and the part of described selection spool (44) is positioned at compensating spool (43).
6. the load sensing multi-way valve for the loader variable system as claimed in claim 1 or 2, it is characterized in that: the mouth (18) on the described pressure compensator (19) is the LS hydraulic fluid port, communicates with LS chamber (17) on valve body (1) plug-in opening.
7. the load sensing multi-way valve for the loader variable system as claimed in claim 1 or 2 is characterized in that: also comprise regeneration function section, comprising: precompression valve (65) and regeneration Fill valve (67).
8. the load sensing multi-way valve for the loader variable system as claimed in claim 1 is characterized in that: described swing arm section (33) or scraper bowl section (32) also comprise overload valve and regeneration Fill valve.
9. the load sensing multi-way valve for the loader variable system as claimed in claim 1 is characterized in that: described additional function section comprises: LS relief valve (4.1), LS unloading valve (4.2) and guide's delivery valve (4.5).
CN 201220478690 2012-09-19 2012-09-19 Load-sensitive multi-way valve used in loader variable system Active CN202851491U (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103807245A (en) * 2014-01-21 2014-05-21 广西柳工机械股份有限公司 Electric proportional overflow cushion valve for engineering machines
CN103807243A (en) * 2014-01-21 2014-05-21 广西柳工机械股份有限公司 Electric proportional decompression cushion valve for engineering machines
CN104006184A (en) * 2014-05-15 2014-08-27 安徽博一流体传动股份有限公司 Signal acquisition valve block assembly
CN104776077A (en) * 2015-02-06 2015-07-15 湘潭大学 Load-sensitive multiway valve with micromotion valve element
CN107269612A (en) * 2016-09-13 2017-10-20 江苏恒立液压科技有限公司 Load sensing multi-way valve system

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103807245A (en) * 2014-01-21 2014-05-21 广西柳工机械股份有限公司 Electric proportional overflow cushion valve for engineering machines
CN103807243A (en) * 2014-01-21 2014-05-21 广西柳工机械股份有限公司 Electric proportional decompression cushion valve for engineering machines
CN104006184A (en) * 2014-05-15 2014-08-27 安徽博一流体传动股份有限公司 Signal acquisition valve block assembly
CN104776077A (en) * 2015-02-06 2015-07-15 湘潭大学 Load-sensitive multiway valve with micromotion valve element
CN104776077B (en) * 2015-02-06 2017-02-22 湘潭大学 Load-sensitive multiway valve with micromotion valve element
CN107269612A (en) * 2016-09-13 2017-10-20 江苏恒立液压科技有限公司 Load sensing multi-way valve system

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