CN203228771U - Valve group for controlling hydraulic retarder and automatic hydraulic retarder comprising same - Google Patents

Abstract

The utility model provides a valve group for controlling a hydraulic retarder and the automatic hydraulic retarder comprising the same. According to the valve group, seven closure round edges and cylinders of a spool are used for matching with a case, under the control of oil pressure produced by oil ways and actions of a first spring and a second spring, seven oil ways form mutually specific communication modes by the aid of movement of the spool, and whether the hydraulic retarder works or not is achieved. The valve group has multilateral reversing and combination valve functions, and oil flow direction and hydraulic force reducing functions in the reversing process can be achieved by throttling grooves of closure edges of the spool. In the valve group, two independent inner cavities are formed by a cavity formed in the spool, two springs, a guide rod and a piston, and throttling holes are formed in corresponding positions of the two inner cavities in order to prevent hydraulic impact in the moving process of the spool.

Description

The valve group of control hydrodynamic retarder and comprise the hydraulic automatic retarder of this valve group

[technical field]

The utility model relates to automobile technical field, particularly a kind of hydraulic automatic retarder of controlling the valve group of hydrodynamic retarder and comprising this valve group.

[background technology]

Commercial vehicle and engineering truck often work under the different road environments, lifting along with current power system ability, the load-carrying of commercial vehicle is increasing, speed of operation is more and more higher, but the size of existing vehicle and the diameter of brake wheel and tire all do not have change, this brake system to commercial vehicle has been brought higher requirement.Along with the pay attention to day by day of people to safety, the installation of the complemental brake system except service brake is also necessary all the more for commercial vehicles such as passenger vehicles.

Complemental brake system (hydrodynamic retarder) is as the auxiliary braking system parts of vehicle, claim the 3rd brake system again, it is by acting on the load that driving system alleviates former car brake system friction lining, vehicle is evenly slowed down, to improve the reliability of motor vehicle braking system, prolong the service life of brake system, and can reduce the vehicle use cost therefrom significantly.Existing Vehicle Hydraulic Retarder, the effect that relies on liquid stream in the blade wheel is converted into the heat energy of liquid with the kinetic energy of vehicle, and the mode by the cooling vessel heat radiation realizes car brakeing again.According to the shape of hydrodynamic retarder epitrochoidal chamber and shape and the angle of blade, and the situation of whole oil circuit has determined the internal characteristic of hydrodynamic retarder.

Nowadays hydrodynamic retarder adopts the way that integrates with Automatic Transmission mostly, the oil pump that utilizes change speed gear box partially or completely provides retarder required fluid, hydrodynamic retarder can use the lubricating oil of automatic transmission with hydraulic torque converter like this, and can utilize the change-speed box radiator to dispel the heat.Can reach very high integrated effect by such design.Make the design of automatic transmission with hydraulic torque converter can realize modularization, multifunction.Because hydrodynamic retarder also all develops into electronic control technology now, hydrodynamic retarder and turbine transformer all belong to hydraulic transmission component, and its control, valve set of pieces, power element etc. mostly are similar.So it is very little hydrodynamic retarder if can be integrated on the hydraulic automatic speed variator cost of its increase.Hydrodynamic retarder can use or part is used the parts such as oil pump, energy storage, complicated oil duct, pressure sensor, control valve body, controller of hydraulic automatic speed variator.

The existing many employings of the hydrodynamic retarder polygon flow regulating valve similar to the power-transfer clutch in the control hydraulic automatic speed variator that is integrated in hydraulic automatic speed variator controls whether make its work to hydrodynamic retarder epitrochoidal chamber internal-filling liquid, just utilizes the principle of change-over valve to come work.But because the working chamber volume of hydrodynamic retarder is bigger, and its work epitrochoidal chamber internal-filling liquid amount when not working differs greatly, if utilize the oil pump of hydraulic automatic speed variator carry out fuel feeding that oil pump certainly will be done very big.Under the situation of nowadays paying much attention to oil consumption, in general to reduce the volume of oil pump, reduce the oil pump loss, this just is badly in need of big flow operating fluid with hydrodynamic retarder work and charges into epitrochoidal chamber and work fast and disagree.

Directly to carry out work oil-filled for hydrodynamic retarder if utilize existing oil pump, and oil pressure moment of whole hydraulic automatic speed variator is reduced, and all power-transfer clutchs of hydraulic automatic speed variator will lose pressure, and the startup work of hydrodynamic retarder will be very slow also.Again in conjunction with bringing very big impact, this decompression is not to be subjected to electric control system controls, will certainly cause very big impact after the power-transfer clutch decompression.Car load ride comfort in influence gearshift and the use hydrodynamic retarder.

For addressing the above problem, prior art all is to install an energy storage (petrol storage tank) additional at hydrodynamic retarder oil-feed oil duct, this energy storage stores fluid at ordinary times, and it utilizes air pressure or other form energies that the fluid moment that stores is squeezed in the epitrochoidal chamber when retarder needs work.Hydrodynamic retarder just can form working cycle at once like this, and can not form the cavity of moment, influence the oil hydraulic system of whole hydraulic automatic speed variator, can enough guarantee the pulsation-free operation pressure, prevent from causing the situation of moment clutch pressure reduction, confusion.

But this mode need install an energy storage and power pipeline and the master cock of controlling it additional to the fluid power automatic transmission with hydraulic torque converter, and this has also increased the trouble point for having increased difficulty with regard to very complicated hydraulic automatic speed variator originally.

In order to overcome above-described problem, the utility model is wished can be under the situation that does not install energy storage and control power pipeline and switch additional, only rely on the appropriate design to commutation spool and each oil circuit to realize to form the quick topping up of hydrodynamic retarder, can realize the function of hydrodynamic retarder work whether change-over valve again.

The utility model just is intended to solve above one or more problems.

[utility model content]

The utility model provides a kind of hydraulic automatic retarder of controlling the valve group of hydrodynamic retarder and comprising this valve group, realize to form the quick topping up of hydrodynamic retarder by the appropriate design to commutation spool and each oil circuit, can realize the function of hydrodynamic retarder work whether change-over valve again.

For achieving the above object, the utility model is by the following technical solutions:

A kind of hydraulic valve bank of controlling hydrodynamic retarder comprises housing, spool, piston, first spring, second spring, and guide rod; Described spool places in the housing, and second spring housing is on guide rod, and an end of second spring and the afterbody of guide rod join, and the other end of second spring and the inner hole surface of spool are joined; Described first spring places between guide rod and the piston; Described spool by spring elastic force and the balance between the pressure that produces of oil pressure locate, be used for regulating the internal characteristic of oil mass size and hydrodynamic retarder.

As preferred embodiment of the present utility model, the modulus of elasticity of described first spring is more than 3 times of modulus of elasticity of second spring.

As preferred embodiment of the present utility model, the inwall of described shell offers many oil circuits, is respectively channel for oiling Y7, the hydrodynamic retarder control oil circuit Y8 of pressure release oil circuit Y1, hydrodynamic retarder vent line Y2, Oil cooler oil-feed oil circuit Y3, the fuel-displaced oil circuit Y4 of oil pump, hydrodynamic retarder oil-feed oil circuit Y5, the fuel-displaced oil circuit Y6 of Oil cooler, hydraulic automatic speed variator; The periphery of described spool offers a plurality of conduits, each conduit arranged at interval around one week of spool and conduit, described conduit guarantees A＜D1＜B, wherein, D1: when electromagnetic valve is exported initial oil pressure P to the control oil circuit, the pressure that this initial oil pressure P produces overcomes the power of second spring but can't overcome the power of first spring time, the amount of compression of second spring; A: the minimum seal distance of the fuel-displaced oil circuit Y2 of Oil cooler in-line Y3 and hydrodynamic retarder; B: the minimum clearance of the fuel-displaced oil circuit Y4 of oil pump and the fuel-displaced oil circuit Y3 of hydrodynamic retarder.

As preferred embodiment of the present utility model, an end of described piston connects first spring, and the other end seals by screw plug, and the one side that described piston contacts with screw plug is cambered surface, and piston is that point contacts with screw plug.

As preferred embodiment of the present utility model, described spool and piston are formed with the first damping cavity Q1 in the enclosure, described spool and guide rod are formed with the second damping cavity Q2 in the enclosure, first spring and second spring are contained in respectively in first damping cavity and second damping cavity, and described spool is provided with cutoff port respectively to reduce the impact in the valve core movement process in the relevant position of first damping cavity and second damping cavity.

As preferred embodiment of the present utility model, the surface of described spool and housing contacts is provided with a plurality of grooves, and this groove is around one week of spool.

Described spool is provided with the guide groove that throttling is used between adjacent oil circuit, the impact that fluid produces when moving to reduce spool makes commutation steadily.

A kind of hydraulic automatic retarder that comprises described valve group, described hydrodynamic retarder comprises the epitrochoidal chamber that is formed by stator ring and rotor wheel and the valve group of controlling the work of epitrochoidal chamber inner fluid, fluid forms the fluid power circulate circle in epitrochoidal chamber, the working process of described hydrodynamic retarder comprises reverse topping up stage and normal work stage, in the reverse topping up stage, described fluid carries out oil-filled from the outer shroud of circulate circle; In normal work stage, described fluid carries out oil-feed from the interior ring of circulate circle, carries out fuel-displaced from outer shroud.

Compared with prior art, the utility model has the following advantages at least: the spool of the utility model valve group is to locate by equilibrium of forces, so, can be so that hydrodynamic retarder be earlier oil-filled by the hydrodynamic retarder oil outlet in the process of commutation, form circulate circle and pressure field, conversion oil inlet then, by the hydrodynamic retarder oil inlet to the epitrochoidal chamber filled with oil that forms fluid power circulation, by the outside oil extraction of the oil outlet of hydrodynamic retarder, so, utilize the fluid power cyclical field continuous working that forms previous stage.Therefore, relating to of the utility model valve group, can be removed generally equipped quick oil-filled system.

[description of drawings]

Fig. 1 is the perspective exploded view after the utility model valve group is removed shell.

Fig. 2 is the part assembling scheme drawing after the utility model valve group is removed shell.

Fig. 3 is the cutaway view after the utility model valve group is removed shell.

Fig. 4 is the cutaway view of the utility model valve group.

Fig. 5 is the cutaway view after the spool in Fig. 4 view moves the D1 distance.

Fig. 6 is the cutaway view of spool under normal mode of operation.

Fig. 7 is the cutaway view after the spool in Fig. 4 view moves the D distance.

Fig. 8 is the structural representation of the utility model spool.

Be labeled as among the figure:

[specific embodiment]

See also Fig. 1 to shown in Figure 4, the utility model valve group comprises: a valve group housing 7 that utilizes case of transmission to do, it plays to cooperate and forms the effect that each isolates oil circuit, control cavity and sealing, location.A spool 6 that is arranged in housing 7 endoporus, it is multistage column reversing valve core, and internal bore forms the feedback force assembly with piston 2, first spring 3, second spring 5 and guide rod 4, and described spool is located according to the feedback force of this assembly formation and the balance between the control-oil pressure.Cover plate 8 plays sealing oil circuit conducting effect, and will control the left side that oil pressure is formed at spool 6.Piston 2 plays spring perch, the effect of locating piece and damper.Screw plug 1 plays the effect of sealing and stopper ring group.

Please consult shown in Figure 4 especially, the inwall of described housing 7 offers 8 oil circuits, is respectively channel for oiling Y7, the hydrodynamic retarder control oil circuit Y8 of pressure release oil circuit Y1, hydrodynamic retarder vent line Y2, Oil cooler oil-feed oil circuit Y3, the fuel-displaced oil circuit Y4 of oil pump, hydrodynamic retarder oil-feed oil circuit Y5, the fuel-displaced oil circuit Y6 of Oil cooler, hydraulic automatic speed variator.

Please consult Fig. 1 and shown in Figure 3 especially, the periphery of described spool 6 offers a plurality of conduits, and in the present embodiment, conduit is 3, and each conduit caves inward around spool one week and from the periphery of spool and forms.See also Fig. 4 to shown in Figure 7, the conduit position of described spool guarantees following situation: when (1) hydrodynamic retarder was not worked, the fluid of the fuel-displaced oil circuit Y4 of oil pump entered in the Oil cooler oil-feed oil circuit Y3 by the interior endless belt between the spool oil circuit; The fluid of Oil cooler cooling is entered the channel for oiling Y7 of hydraulic automatic speed variator by the interior endless belt between the spool oil circuit by the fuel-displaced oil circuit Y6 of Oil cooler; Simultaneously, retarder vent line Y2 is communicated with electromagnetic valve that the fluid that guarantees epitrochoidal chamber in time discharges the work of (2) control hydrodynamic retarder by the pressure release oil circuit to control oil circuit Y8 output initial control oil pressure and pressure hour with the pressure release oil circuit, hydrodynamic retarder oil road Y2 and Oil cooler oil-feed oil circuit Y3 are with very little channel connection, and Oil cooler oil-feed oil circuit Y3 continues to communicate with the fuel-displaced oil circuit Y4 of oil pump, that is to say, hydrodynamic retarder oil road Y2 and Oil cooler oil-feed oil circuit Y3 and three oil circuits of the fuel-displaced oil circuit Y4 of oil pump communicate, like this, fluid can enter hydrodynamic retarder via hydrodynamic retarder oil road Y2, be that the fuel-displaced oil circuit Y4 of oil pump oil circuit is always to Oil cooler oil-feed oil circuit Y3 fuel feeding, and the connection fuel-displaced oil circuit Y4 of oil pump and hydrodynamic retarder oil road Y2, simultaneously, the fluid of the fuel-displaced oil circuit Y6 of Oil cooler continues to enter by the interior endless belt between the spool oil circuit channel for oiling Y7 of hydraulic automatic speed variator; When (3) controller of hydraulic automatic speed variator acts on the control presssure in spool 6 left sides by the electromagnetic valve increasing, this control presssure makes spool move, the movement of spool makes the fuel-displaced oil circuit Y2 of hydrodynamic retarder be communicated with Oil cooler oil-feed oil circuit Y3, simultaneously, the fuel-displaced oil circuit Y6 of Oil cooler is communicated with the oil-feed oil circuit Y5 of hydrodynamic retarder, be that the fuel-displaced oil circuit Y2 of hydrodynamic retarder is communicated with Oil cooler oil-feed oil circuit Y3, simultaneously, the fuel-displaced oil circuit Y6 of Oil cooler is communicated with the oil-feed oil circuit Y5 of hydrodynamic retarder, the hydrodynamic retarder oil-feed oil circuit Y5 of the fuel-displaced oil circuit Y4 of oil pump UNICOM, be that hydrodynamic retarder enters normal mode of operation, at this moment, fluid is guided Oil cooler via the fuel-displaced oil circuit Y2 of hydrodynamic retarder into by Oil cooler oil-feed oil circuit Y3, cooled fluid enters the oil-feed oil circuit Y5 of hydrodynamic retarder via the fuel-displaced oil circuit Y6 of Oil cooler, meanwhile, the fuel-displaced oil circuit Y4 of oil pump constantly provides fluid to hydrodynamic retarder oil-feed oil circuit Y5, so finishes a circulation.

Generally all be oil-filled in the epitrochoidal chamber of being formed by stator ring and rotor wheel in the hydrodynamic retarder working process, fluid is because the centrifugal effect of rotor wheel blade, throw away along rotor inner wall, impact stator ring blade and inner chamber wall, and then be back to rotor wheel, so just form the fluid power circulate circle, and formed the pressure reduction at the different circulate circle diameter of epitrochoidal chamber place, and then made the fluid power circulation to go on.

Usually will be through the whipping of rotor wheel by the epitrochoidal chamber filled with oil, be in order to form epitrochoidal chamber circulate circle center pressure minimum after the working cycle like this, outer ring compression is the highest, oil-feed is located in the circulate circle encircles like this, and the fuel-displaced outer shroud that is located at circulate circle is the most favourable to carry out continuously with circulation.But this has caused certain delay time with regard to the formation for incipient working cycle circle.If can carry out oil-filledly from the epitrochoidal chamber outer shroud, the blade that the liquid that has so just entered epitrochoidal chamber is subjected to the maximum line velocity of the outer shroud of rotor wheel at once stirs, and directly rushes at the stator wall, forms circulate circle with the fastest speed and the minimum distance that charges into.The time that forms working cycle will reduce greatly like this.If formed working cycle circle, then the turnover oil duct of hydrodynamic retarder all has certain pressure, like this oil circuit of hydrodynamic retarder is connected on the oil circuit of hydraulic automatic speed variator just not cause the pressure of hydraulic automatic speed variator oil circuit to change excessive.

At above theory, the utility model is fully recognized that this point: whether hydrodynamic retarder work is to realize with a polygon change-over valve, but for the influence of little minimizing to the oil piping system pressure of hydraulic automatic speed variator of trying one's best, hydrodynamic retarder must form pressure field at its fuel-displaced oil circuit as early as possible, in order to realize this purpose, the utility model designed in the process of commutation earlier oil-filled by the hydrodynamic retarder oil outlet, the mode of stopping up the hydrodynamic retarder oil inlet makes it form circulate circle and pressure field at once, then carry out the conversion oil inlet, by the hydrodynamic retarder oil inlet to the epitrochoidal chamber filled with oil that forms fluid power circulation, by the outside oil extraction of the oil outlet of hydrodynamic retarder, so just can utilize the fluid power cyclical field continuous working that forms previous stage.Can remove generally equipped quick oil-filled system based on above theory.

For realizing above-mentioned theory, the work of spool must have a control oil pressure to realize by control oil circuit Y8.First spring 3 corresponding with the control oil pressure and the modulus of elasticity between second spring 5 differ greatly, and the modulus of elasticity of first spring 3 is more than 3 times of second spring 5.Purpose is that first spring 3 is almost motionless when making 5 compressions of second spring, so just can form two movement travels in succession.Utilize this stroke to design the dam phase mutual edge distance on limit of each oil circuit and spool 6 just, form the quick oil-filled stage of direction before the commutation.

Please extremely shown in Figure 4 in conjunction with Fig. 1, valve group intraware is, second spring 5 is enclosed within on the guide rod 4, guide rod 4 insert spool 6 endoporus and with its formation annular seal space, first spring 3 is positioned at guide rod 4 rear portions, the other end of first spring is enclosed within on the piston 2, the piston 2 formation annular seal space that matches with the endoporus of spool 6 afterbodys.

Specific implementation process is as follows:

(1) hydrodynamic retarder service condition (as shown in Figure 4) not, control oil circuit Y8 is inner not to have the control oil pressure, and spool 6 is positioned at the high order end of the endoporus of shell 7 under the effect of first spring 3 and second spring 5.At this moment the fluid of the fuel-displaced oil circuit Y4 of oil pump enters Oil cooler oil-feed oil circuit Y3 through the interior endless belt of spool, enter the channel for oiling Y7 of hydraulic automatic speed variator through the fluid of Oil cooler cooling by the fuel-displaced oil circuit Y6 of Oil cooler, each rotating part of hydraulic automatic speed variator is cooled off.So just realized isolating hydrodynamic retarder and not influencing the effect that hydraulic automatic speed variator fluid circulates.

(2) when the electromagnetic valve of control hydrodynamic retarder work is controlled oil pressure P to control oil circuit Y8 output is initial, the pressure that this oil pressure P produces is less, only can be with 5 compressions of second spring, second spring, 5 amount of compressions are D1, at this moment the endoporus plane of spool 6 contacts with the top of guide rod 4, second spring 5 will no longer act on spring force, and then be transmitted the spring force of first spring 3 by guide rod.Because the modulus of elasticity of first spring 3 is very big, initial control presssure is less, can't overcome the power of first spring 3, causes under the initial control presssure situation, and spool 6 can only mobile D1 displacement.See also shown in Figure 5ly, and the minimum seal distance of the Oil cooler oil input channel Y3 of spool 6 and the fuel-displaced oil circuit Y2 of hydrodynamic retarder is A, and the minimum clearance of the fuel-displaced oil circuit Y4 of oil pump and the fuel-displaced oil circuit Y3 of hydrodynamic retarder is B.Its three's magnitude relationship is A＜D1＜B.Therefore, when spool moves (modulus of elasticity of second spring 5 is very little) little displacement D1 rapidly under the effect of control oil pressure, the endless belt that then seals the fuel-displaced oil circuit Y2 of hydrodynamic retarder and Oil cooler oil input channel Y3 disappears, there is a very little passage between the two, at this moment, the fuel-displaced oil circuit Y2 of hydrodynamic retarder and Oil cooler oil input channel Y3 and the fuel-displaced oil circuit Y4 of oil pump communicate with each other, like this, the fluid of the fuel-displaced oil circuit of oil pump can enter hydrodynamic retarder via the fuel-displaced oil circuit Y2 of hydrodynamic retarder, move when spool under the situation of D1, the fuel-displaced oil circuit Y4 of oil pump is then always to Oil cooler oil input channel Y3 fuel feeding, and the connection fuel-displaced oil circuit Y4 of oil pump and the fuel-displaced oil circuit Y2 of hydrodynamic retarder oil circuit.Like this, the high-voltage oil liquid that is come out by oil pump is charged into the outer shroud of hydrodynamic retarder circulate circle with very fast speed by the fuel-displaced oil circuit Y2 of hydrodynamic retarder, drive in the linear velocity that enters epitrochoidal chamber and be subjected to the rotor wheel maximum, form at once and carry out the conversion of kinetic energy and pressure energy, form pressure field, and set up the working cycle circle rapidly, prevent that the pressure of the fuel-displaced oil circuit Y4 of oil pump from reducing rapidly.

At this moment by the dam reasonable matched position on limit of design spool 6 and retarder oil-feed oil circuit Y5, make when displacement is D1 that the oil-feed oil circuit Y5 of hydrodynamic retarder also under the closed state of spool 6, can not form hydrodynamic retarder by the situation of oil-feed oil circuit Y5 oil extraction.

(3) after the quick oil-filled stage finished, hydrodynamic retarder had formed working cycle.The controller of hydraulic automatic speed variator strengthens the control presssure that acts on spool 6 left sides by electromagnetic valve.Make spool will overcome the spring force that overcomes first spring 3 behind the compressive force of second spring 5 again, at this moment, the scope that spool moves is D2～D, D2=D-B, D is the displacement that spool moves to extreme position, this process will be carried out the conversion of liquid stream, and the left side excursion that realizes spool 6 is pressed onto screw plug 1 the most at last is D.The fuel-displaced oil circuit Y2 of oil circuit hydrodynamic retarder this moment is communicated with Oil cooler oil-feed oil circuit Y3 fully by spool 6, and the fuel-displaced oil circuit Y6 of Oil cooler is communicated with the oil-feed oil circuit Y5 of hydrodynamic retarder.Make hydrodynamic retarder can enter normal steady-working state, the fluid of high pressure-temperature is guided Oil cooler via the fuel-displaced oil circuit Y2 of hydrodynamic retarder into by Oil cooler oil-feed oil circuit Y3, is entering the oil-feed oil circuit Y5 of hydrodynamic retarder through cooled fluid via the fuel-displaced oil circuit Y6 of Oil cooler.At this moment the fuel-displaced oil circuit Y4 of oil pump also is communicated with hydrodynamic retarder oil-feed oil circuit Y5.When distance that spool moves was within D2～D scope, described spool can remain on the optional position, so, change the open area of fluid by the variation of position, to change the size of turnover fluid, finally change the performance size of retarder work, change the lock torque of retarder exactly.

(4) if hydrodynamic retarder need quit work, act on the control oil pressure pressure release in spool 6 left sides so, spool 6 moves to left rapidly under the combined action of first spring 3 and second spring 5, the oil-feed oil circuit Y5 that cuts off hydrodynamic retarder and the fuel-displaced oil circuit Y6 of Oil cooler are communicated with the fuel-displaced oil circuit Y4's of oil pump, and hydrodynamic retarder oil-feed oil circuit Y5 is sealed.The fuel-displaced oil circuit Y2 of cut-out hydrodynamic retarder is communicated with Oil cooler oil-feed oil circuit Y3's, and it is connected with draining oil circuit Y1, makes fluid can discharge the hydrodynamic retarder epitrochoidal chamber fast.Simultaneously, when retarder was not worked, the fuel-displaced oil circuit Y2 of hydrodynamic retarder was communicated with draining oil circuit Y1, can also guarantee that the fluid in the retarder epitrochoidal chamber is in time discharged from the draining oil circuit, can reduce unnecessary resistance like this, and then reduce oil consumption.

In order to realize the throttling and the effect that reduces the power of surging in the above-mentioned commutation process, made corresponding throttling channel on the multistage ladder type face of cylinder of spool 6.In order to reduce displacement and the impact excessively in the valve core movement process, the first damping cavity Q1 and the spool 6 that forms at spool 6 and piston 2 done first and second cutoff ports with the relevant position of the second damping cavity Q2 of guide rod 4 formation especially, play to reduce and impact, smooth-going effect commutates.

Like this, when spool 6 moved, two adjacent oil circuit fluid just can utilize the such guide groove of F1-F6 to play throttling when being communicated with, and reduce and impact, and smooth-going effect commutates.

In order to make the movement of carrying out two displacements that spool 6 can be smooth-going, special with piston 2 and guide rod 4 inner chamber of spool 6 is divided into two relatively independent spaces, namely the first damping cavity Q1 and the second damping cavity Q2 hold first spring 3 and second spring 5 respectively in these two spaces.When commutation work is carried out, the liquid in the cavity need be discharged, so impact and the power of surging in order to reduce, designed the first segment discharge orifice K1 that is arranged in the first damping cavity Q1 and the second cutoff port K2 that is arranged in the second damping cavity Q2.

The spool 6 of this design, each of piston 2 participates in sealing the relief groove that all has varying number with the outer ring surface of commutation, utilize relief groove to realize blocking the inner effect of leaking mutually of two adjacent oil ducts, and realize the smooth-going and effect that prevents spool and piston clamping stagnation in the commutation process by relief groove.

Because piston 2 plays the effect of spring perch, locating dowel pin and a seal ring at this valve group place, but because spool 6 is understood along with temperature the conversion in the power of surging and the moving process and axial inclination takes place.So in order to prevent the spool clamping stagnation, an end of piston 2 contact screw plugs 1 is made cambered surface, piston 2 just can adapt to spool 6 and favours and carry out adaptive adjustment like this, and the energy actv. play the effect that prevents the spool clamping stagnation.

Based on above-mentioned design, the displacement of change-over valve is arranged to two sections, first section realization is to the oppositely topping up fast of hydrodynamic retarder, and second displacement realizes normal working cycle.Utilize the valve core inside structure cleverly, two different springs of modulus of elasticity are set offset the fluid control power that configures.

Inner chamber at spool is provided with two cavitys, in order to hold spring and the effect that plays the damping oil extraction.

In order to make in the commutation process can smooth-going carrying out, prevent the hydraulic pressure abrupt change, made along the circumferential direction uniform guide groove at each place, throttling limit of spool, the form of each guide groove and size all are fit to the smooth-going demand that commutates.Utilize that the mode of the throttling of guide groove and the through-flow diameter of conversion power realizes that liquid levelling in the commutation process is suitable, the flowing of gradual change.Prevent from using in the process of hydrodynamic retarder and impact.

Utilize the housing of hydraulic automatic speed variator as the outer wall of this combine valve, utilize the controller of hydraulic automatic speed variator to set corresponding control program, come control action in pressure size and the speed of spool 6 control ends, and then the speed of whether controlling hydrodynamic retarder work, working and carry out, and the size of the brake torque that produces.

The valve group of this design is hydrodynamic retarder, hydraulic automatic speed variator, and the oil circuit of the Oil cooler of hydraulic automatic speed variator is designed into together cleverly.Make Oil cooler when retarder is not worked, can cool off the fluid of automatic transmission with hydraulic torque converter, when hydrodynamic retarder is worked, can cool off hydraulic automatic speed variator and hydrodynamic retarder simultaneously by the commutation of oil circuit.Brought the advantage of modular design for hydraulic automatic speed variator.Reduce the parts that install additional.And cost-cutting.

Claims (8)

1. valve group of controlling hydrodynamic retarder is characterized in that: comprise housing (7), spool (6), piston (2), first spring (3), second spring (5), and guide rod (4); Described spool places in the housing, and second spring housing is on guide rod, and an end of second spring and the afterbody of guide rod join, and the other end of second spring and the inner hole surface of spool are joined; Described first spring places between guide rod and the piston; Described spool by spring elastic force and the balance between the pressure that produces of oil pressure locate, be used for regulating the internal characteristic of oil mass size and hydrodynamic retarder.

2. valve group as claimed in claim 1, it is characterized in that: the modulus of elasticity of described first spring is more than 3 times of modulus of elasticity of second spring.

3. valve group as claimed in claim 2, it is characterized in that: the inwall of described housing offers many oil circuits, be respectively the channel for oiling (Y7) of pressure release oil circuit (Y1), hydrodynamic retarder vent line (Y2), Oil cooler oil-feed oil circuit (Y3), the fuel-displaced oil circuit of oil pump (Y4), hydrodynamic retarder oil-feed oil circuit (Y5), the fuel-displaced oil circuit of Oil cooler (Y6), hydraulic automatic speed variator, and hydrodynamic retarder control oil circuit (Y8); The periphery of described spool offers a plurality of conduits, each conduit arranged at interval around one week of spool and conduit, described conduit guarantees A＜D1＜B, wherein, D1: when electromagnetic valve is exported initial oil pressure P to the control oil circuit, the pressure that this initial oil pressure P produces overcomes the power of second spring but can't overcome the power of first spring time, the amount of compression of second spring; A: the minimum seal distance of Oil cooler in-line (Y3) and the fuel-displaced oil circuit of hydrodynamic retarder (Y2); B: the minimum clearance of the fuel-displaced oil circuit of oil pump (Y4) and the fuel-displaced oil circuit of hydrodynamic retarder (Y3).

4. valve group as claimed in claim 1, it is characterized in that: an end of described piston connects first spring, and the other end seals by screw plug, and the one side that described piston contacts with screw plug is cambered surface, and piston contacts for point with screw plug.

5. as claim 1 or 3 described valve groups, it is characterized in that: described spool and piston are formed with first damping cavity (Q1) in housing, described spool and guide rod are formed with second damping cavity (Q2) in housing, first spring and second spring are contained in respectively in first damping cavity and second damping cavity, and described spool is provided with cutoff port respectively to reduce the impact in the valve core movement process in the relevant position of first damping cavity and second damping cavity.

6. as claim 1 or 3 described valve groups, it is characterized in that: the face that described spool contacts with housing is provided with a plurality of grooves, and this groove is around one week of spool.

7. valve group as claimed in claim 3, it is characterized in that: described spool is provided with the guide groove that throttling is used between adjacent oil circuit, and the impact that fluid produces when moving to reduce spool makes commutation steadily.

8. hydraulic automatic retarder that comprises the described valve group of claim 1, it is characterized in that: described hydraulic automatic retarder comprises the epitrochoidal chamber that is formed by stator ring and rotor wheel and the valve group of controlling the work of epitrochoidal chamber inner fluid, fluid forms the fluid power circulate circle in epitrochoidal chamber, the working process of described hydrodynamic retarder comprises reverse topping up stage and normal work stage, in the reverse topping up stage, described fluid is from the outer shroud oil-feed of circulate circle; In normal work stage, described fluid carries out oil-feed from the interior ring of circulate circle, and is fuel-displaced from outer shroud.

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