CN101111684A

CN101111684A - Hydraulic drive system

Info

Publication number: CN101111684A
Application number: CNA2005800472868A
Authority: CN
Inventors: 乔治·卡德里科
Original assignee: Haldex Hydraulics AB
Current assignee: Concentric Rockford Inc
Priority date: 2004-12-01
Filing date: 2005-12-01
Publication date: 2008-01-23
Anticipated expiration: 2025-12-01
Also published as: ZA200704352B; CN101111684B

Abstract

A hydraulic drive system for an actuator uses a pair of pressure compensated hydraulic machines to control flow to and from the drive chambers of the actuator by varying the controlled pressure of one of the machines. The machines are mechanically coupled to permit energy recovery and charge an accumulator to store supplies energy. The drive system may be combined with other services including a transmission for incorporation in a vehicle. The transmission uses a pressure compensated supply and torque control of the wheels.

Description

Hydraulic driving system

Technical field

The present invention relates to a kind of energy delivery system, and relate more particularly to utilize the system of hydraulic fluid as energy transmission medium.

Background technique

Be well known that, from giving load by the instrumentality of hydraulic driving system with energy transfer such as motor or the such power source of internal-combustion engine.This system typically has by the pump of drive power source and the motor that is connected in the load.By adjusting the hydraulic flow between pump and the motor, can give load with motion, hold it in the fixed position or influence its configuration.

The control that fluid flows realizes by valve mechanism usually, and in the simple form of valve mechanism, valve can open or close flowing and the motion of regulating load thus between pump and the motor simply.Not efficient relatively aspect the energy that this valve system is depleted on whole valve.Under typical installation situation, valve can be closed, and needs pump to resist safety valve in the center and transmits pressure.The pressure that is fed to fluid falls as heat loss thus.In a center configuration form of opening, need carefully make valve, so that obtain the transmission between zero mobile and complete flowing, the retentive control of load simultaneously and the loss that the mobile metering on the whole valve can cause energy.

Thus, it is relatively complicated and with high validity manufacturing, so that obtain the necessary control function to be used to control mobile valve.So, valve is tending towards by specialization and can't be provided at the flexibility of implementing under the different control strategies.Be the most significantly, because by mobile metering that strides across whole aperture realized control, so when the control fluid is mobile, there is significant energy loss inherently.By flowing on the port that is tied that is controlled at the device portal place, control valve can adjustment movement.Because control valve is generally a tubular article, provide similar constraint port, to discharge mobile and to cause significant energy loss.

Utilize servo-valve in order to reduce the required steering force of valve, to be well known that, wherein control fluid and flow with pilot operationp.With this collocation form, the maincenter valve makes a pair of directed flow dynamic balancing and being moved, and flows and reduces another and flow to increase one of them.The change of flowing is used to control valve and operates hydraulic pressure installation.The required power of mobile pilot valve is less than the power that is used for control valve, and the control that can obtain to strengthen thus.Yet, cause significant loss with the continuous-flow of high pressure by pilot valve.Control valve itself also bears owing to striding across the mobile deficiency of measuring the energy loss that causes on the port that is tied, and thus, although the control that strengthens is provided, energy loss is remarkable.

Summary of the invention

Therefore, the objective of the invention is to eliminate or reduce above-mentioned defective.

Under general situation, the invention provides a kind of hydraulic driving, wherein the variable capacity hydraulic machine that flows through of coming from actuator is controlled.This machine is pressure compensated, so that keep the pressure in the actuator.Provide control signal, to adjust the pressure of being kept and to regulate thus from flowing that actuator comes.

Therefore according to an aspect of the present invention, provide hydraulic driving system, comprising: actuator, have a pair of chamber, be set to use the fluid from chamber and the motive force that obtains, with mobile driving component in the opposite direction.Each chamber respectively with a pair of variable capacity hydraulic machine in one be connected, each machine all has pressure compensation control, the capacity that is operable as machine is adjusted into the predetermined pressure of keeping in the chamber.Can at least one machine, operate hypervelocity control, to change its capacity and to allow from the corresponding sports of one of them chamber effluent fluid and permission driver part.

Description of drawings

With reference to the accompanying drawings only the mode by example present invention is described, wherein:

Fig. 1 is the schematic representation that is used for the hydraulic unit driver of linear actuators.

Fig. 2 is the detailed view of assembly that is used for the driver of Fig. 1.

Fig. 3 is the schematic representation that is similar to Fig. 1 that has the linear actuators that improves control.

Fig. 4 is for implementing the further schematic representation of the linear actuators that is similar to Fig. 1 of control function.

Fig. 5 is the schematic representation of rotating driver.

Fig. 6 is the schematic representation that has another embodiment of the driver that strengthens the energy recovery capability.

Fig. 7 is the view in conjunction with hydraulicdriven vehicle.

The hydraulicdriven schematic representation of Fig. 8 in Fig. 7, being utilized.

Fig. 9 is the response curve of the difference response under the different operating condition.

Embodiment

Referring to Fig. 1, hydraulic driving system 10 comprises actuator 11, has cylinder body 12, has the piston 14 that is supported in the cylinder body 12.Piston 14 is connected with piston rod 16, and this piston rod 16 extends from the opposite end of cylinder body 12.Cylinder body 12 is further divided into chamber 18 to

piston

14 and 20, two chambers are connected with

supply line

22,24 by

port

26,28 respectively.Bar 16 is connected with load 30, schematically is shown as the mass of horizontal slip.

Supply line

22,24 is connected with the outlet of a pair of variable-displacement hydraulic machine 32,34.

Machine

32,34 is generally the wobbler device, and wherein the angle of inclination of wobbler has determined the capacity of machine.Alternatively, described device is a radial piston pump, and wherein the variation of the control ring degree of eccentricity has determined the capacity of machine.Machine the 32, the 34th, reversible, all under pump pattern and motoring mode, operate to allow each.The details of these machines is known, and need not further describe.The certain preferred embodiment of this machine is disclosed in copending application PCT/US2005/004723, and its full content merges with for referencial use at this.

Machine

32,34 is connected to prime mover 38 by common drive shaft 36, normally motor or internal-

combustion engine.Machine

32,34 returns hopper 40 from hopper 40 receptions and with fluid.Each machine all has

capacity regulating mechanism

42,44, and its configuration can be adjusted

motor

46,48 by wobbler and adjust.

Motor

46,48 can be operated independently and control by each control unit 47,49.As can seeing in more detail from Fig. 2, each

control unit

47,49 receives from control module 50 and the control signal of coming, as the result of manipulation of manual control 51.Control module 50 is communicated by letter with

control unit

47,49 by

signaling line

52,54 respectively.Each of

signaling line

52,54 all comprises reference pressure signal 61 and wobbler position feed back signal 57.Input to control module is provided by controller 51, and this control is shown as manual control, although clearly this can control that function automatically produces or as the part of program sequencing by other.

Control unit

47,49 is similar and therefore only one of them is described in detail.The pressure feedback signal that

control unit

47,49 comes from

supply line

22,24 by internal signal wire 56 receptions respectively.Also can obtain to be used for the feedback signal of wobbler dislocation and the feedback signal that obtains machine rotational speed by signaling line 58 by signaling line 57.

Pressure reference signal 61 and pressure feedback signal 56 compare at pressure control driver 63 places, and this driver is connected to wobbler driver 67 by guide line 65.Wobbler driver 67 produces output error signal 68.This error signal 68 is applied to valve driver 69, and this valve driver is output as drive signal 62.

Drive signal 62 is applied to the actuation coil 64 of the center valve 66 of closing, the motion of this centre valve gate control motor 46 and therefore control the capacity of each machine 32.Valve 66 has valve position feedback signal 70, and this signal 70 is fed to valve driver 69, thereby drive signal 62 is the difference between error signal 68 and the valve position signal 70.

In operation, load 30 is static at first and

capacity adjustment member

42,44 is orientated the zero capacity in fact that has maximum system pressure as with respect to

machine

32,34 at first, is the grade of 5000psi at each

port

26,28 place usually.

Machine

32,34 obtains this state when reference signal 61 is applied on the pressure control driver 63, and any pressure loss all can be come accommodating fluid with mobile wobbler 67 for wobbler 67 provides signal.This can cause the increase of sensed pressure in the feedback line 56 and produce net value at driver 67 places is 0 summation.Under this state, live axle 36 is rotating

machinery

32,34 simply, can not produce output at

supply line

22,24 places.Fluid be locked in the

chamber

18,20 in fact and thus piston 14 be suppressed with respect to the motion of cylinder body 12.The leakage part of any system can cause the pressure of each

pipeline

22,24 to reduce, and produces from pressure control driver 63 and the corresponding error signal of coming, and will adjusting each

member

42,44, thereby keeps pressure.

For travelling load 30, manually to control 51 and on the direction that load will be moved, move, this direction is indicated by the arrow X among Fig. 1.For initial purpose of description, suppose that control 51 provides the step function of simple fixed value, promptly " opens " or " closing " control module 50.Embodiment subsequently will describe alternative control strategy.When manually control 51 was moved, signal 33 was provided to control module 50, and it produces corresponding signal in

guide line

53,54, under 52 situation, to influence the motion on the required direction.

Pressure reference signal 61 need to be set to nominal minimum pressure, be 100psi at port 26 places for example, thereby the signal on the guide line 65 is also indicated the increase of machine 32 capacity under motoring mode, to reduce the pressure at port 26 places.Wobbler 67 provides output error signal to valve driver 69 thus, has indicated required valve location, and this position can make machine 32 place motoring mode, to reduce the pressure in the port 26 and to allow fluid to flow from chamber 18.Valve position feedback signal 70 has been indicated the neutral position of valve 66, so valve driving signal 62 is applied to stopper 64, to reduce error and to open valve 66 thus.

At first, the capacity of machine 32 will increase, and enough be used for the decline of the pressure at port 26 places, and signal 57 corresponding slave controllers 50 and the reference signal 61 of coming.Control signal 65 is reduced to zero thus.Valve position feedback signal 70 works by valve driver 69 thus, with throttle down 66 and suppress the further motion of wobbler 42.The increase of any machine capacity all will reduce the pressure at port 26 places, make it to be lower than the pressure that is provided with by reference pressure 61, and control signal 65 will play the reduction capacity and make pressure recovery arrive the effect of reference pressure 61.

Because the pressure at port 26 places reduces, when the reference signal 61 that is associated with control unit 49 was not modified, the pressure in the chamber 20 maintained the maximum value of setting.The pressure difference of effect causes the initial movement of piston 14 on whole piston 14, and this has reduced the pressure at port 28 places again.The pressure control of control unit 49 drives 63 and produces control signal 65 thus, and this control signal can produce output error and cause machine 34 increase capacity under the pump pattern wobbler driver 67, to keep reference pressure.The pressure mobile and port 26 that the motion initiation of piston 14 comes from port 26 will be increased to name at this and be provided with more than the pressure.Pressure controling signal 65 can to increase the capacity of machine 32 under motoring mode, be kept required nominal pressure simultaneously by 67 operations of wobbler driver subsequently.Pressure difference on the whole piston 14 will make mass 30 quicken thus.Because mass 30 is quickened, thereby the capacity of the machine 34 under the pump pattern continues to increase providing fluid to keep reference pressure, and the capacity of the machine under motoring mode 32 will similarly increase and keep name pressure is set.Mass 30 is quickened can continue to quicken, and the capacity of

machine

32,34 adjusts under pressure compensation control, thus keep at

port

26,28 places they separately pressure is set.When machine 34 obtained maximum capacity, mass was no longer quickened but is obtained stable speed, and the pressure that the pressure at its middle port 28 places is maintained maximum reference pressure and port 26 places is maintained nominal low-pressure.

In the simple form of the control that provides by manual control 51, actuator 10 will continue moving mass body 30 on the direction that controller 50 sets.When having obtained the desired location of mass 30, as the observation by the operator, manual actuator 51 returns the central position, makes reference pressure 61 be increased to pressure maximum.In order to obtain by the indicated pressure of reference signal 61, the capacity of machine 32 will reduce so that the pressure in the port 28 is increased to the value of setting.Pressure difference on the whole piston 14 is removed and mass 30 is slowed down.The capacity of machine 34 also is lowered thus, pressure is maintained the value of setting and when the mass decelerates,

machine

32,34 all little by little is reduced to minimum capacity.Pressure at

port

26,28 places is identical subsequently and keep load 30 static.It should be noted that during movement the modulation of reference pressure 61 only is applied on the machine 32 and machine 34 is operated to follow the motion of piston 14 simply under the pressure compensation pattern.

The motion of manual control 51 in the opposite direction produces drive signal equally by signaling line 54 application controls signals with valve 66 places at control unit 49, and the reduction of required pressure has increased the capacity of machine 34 and produced responsive movement in the opposite direction.

Between the moving period of load 30, wobbler position feed back signal 57 is applied to control module 50, so that the indication to mode of machine operation to be provided, i.e. and pump or motoring mode, and be provided in the anticipation control of revising aspect the reference pressure signal 61.

In order to regulate the different operating condition, as shown in Figure 9, the optimal response that rotation feedback signal 58 is used to change the initial conditions of ramp function and obtains the pressure control aspect.When the pressure supply of the increase that responds reference signal 61 increased, as institute's sensing in the pressure sensing line 56, slope initial point T arrived controller 63, changed pressure signals at this some place controller 50.Controller 50 is inbound pacing feedback signal 58 and change initial value also, the T that is inversely proportional to as the speed with the institute sensing ₁And T ₂Shown in.With low rotational speed, Pressure gain (pressure increase speed) is very low, because since the relatively low speed of pump and motoring mode in the machine, the time lengthening of system responses.Yet under higher rotational, pressure gain rate is higher.Thereby, under higher RPM, initial value T ₁Be the lower pressure value, and under low RPM, initial value T ₂Be the elevated pressures value.By this way, system responses can be complementary with the change operational condition of system.

Provide the rotational speed of machine by feeding back 58, thereby can be used for changing the response change reference pressure signal 61 of machine.For optimum response is provided, promptly suppress overshoot and make down to dash to minimize, revise by ramp function to the control signal of valve 66.

Alternatively, the angle configurations of

wobbler

42,44 can be used to change the beginning of modification.In this case, when improving the pressure of being supplied when the increase that responds reference signal 61, as in 56 sensings of pressure sensing line, slope initial point T arrives controller 63, changes pressure signals at this some place controller 50.Controller 50 also receives wobbler feedback signal 57 and changes initial point, as with as described in shown in the detection position T1 and T2 that are inversely proportional to.Under low wobbler angle, Pressure gain (pressure is advanced the speed) is low, because since the relatively low speed of pump and motoring mode in the

machine

34,32, the time lengthening of system responses.Yet under higher wobbler angle, pressure gain rate is higher.Thereby, under higher wobbler angle, initial value T ₁Be the lower pressure value, and under low wobbler angle, initial value T ₂Be the elevated pressures value.By this way, system responses can be complementary with the change operational condition of system.

By feeding back 58 rotational speeies that machine is provided, the response that can be used for changing machine changes reference pressure signal 61.For optimum response is provided, promptly suppress overshoot and make down to dash to minimize, revise by ramp function to the control signal of valve 66.

It should be understood that by utilizing the variable capacity of

machine

32,34 on public driver can be directed to initiatively son again by axle 36 from flattening chamber fluid discharged energy, machine or other machines under the pump condition will be described in more detail below.

Fluid produces moment of torsion when the fluid that flattens chamber (being 18) above example is flowing in it and flows through each machine 32.The moment of torsion that is produced partly depends on the capacity of machine and is applied to live axle 36 to replenish by initiatively sub 38 moments of torsion that applied.In some cases, for example be subjected to the motion of the auxiliary load 30 of gravity, be enough to maintain the pressure that is provided with the other machines, and in other cases,, also need the energy that comes from son 38 initiatively except the moment of torsion that recovers from a moment of torsion that machine obtained.In needs additional torque part, initiatively son control increases perception needs (for example, underspeeding) and makes corresponding response under the situation of compression-ignition engine.

The deceleration of mass 30 also provides energy source, and it can recover by the mechanical linkage of machine 32,34.As mentioned above, when neutral position was got back in control 51, the condition of machine 32 can be kept maximum reference pressure.Because the persistent movement of the mass 30 of its kinetic energy must be resisted pressure maximum by machine 32 thus and work, this machine still is in motoring mode.Machine 32 is driven by the fluid of discharging from chamber 18 thus, and significant moment of torsion is applied on the live axle 36.Apply moment of torsion up to mass with to get back to the wobbler of zero capacity in fact all static.

In some cases, by moving control 51 in the opposite direction, load 30 can be slowed down with the speed of maximum, promptly passes through neutral position.This athletic meeting causes signal to be used by signaling line 54, with required nominal low-pressure of indication port 28 and the pressure maximum in the port 26.Machine 32 reduces its capacity thus, and keeping pressure maximum, and machine 34 reduces its capacity similarly but speed only can be kept the nominal low pressure in the port 28.Maximum pressure differential is employed subsequently, so that mass decelerates and make it static.Wobbler moves to zero displaced position gradually, controls 51 this moment and can be released and the equal pressure balance is applied to each chamber.Maintain reversed position if control 51, then machine 34 can move to motoring mode and machine 32 moves to the pump pattern, and load begins to move in the opposite direction.

As mentioned above, manually control 51 or " opening " or " pass ", but scaling signal can incorporate in the manual control 51 into, obtaining evolution reaction, thus the ratio that moves into that the movement rate of load and control 51 begin from neutral position.In this case, the magnitude of control signal 53 and the ratio that moves into of controlling 51.Signal 52 is used for pressure compensated reference pressure signal with foundation, and the dislocation of itself and controller 50 is proportional.Need to suppose the motion of mass on the arrow directions X, then the capacity of machine 32 will be adjusted, thereby the pressure at port 26 places obtains this value.The pressure at port 28 places maintains reference levels, thereby the pressure difference on the whole piston 14 can be modulated thus and be quickened to be controlled.

The form that is provided with as shown in fig. 1 provides a kind of simple manual feedback, but control signal can be modified to the piston control that actuator 18 is provided, and as shown in Figure 3, wherein is " a " similar assembly in order to know that reference character is used in reference to for suffix.In the embodiments of figure 3, manually control 51a and provide ratio control signal to control module 50a.Obtain position feed back signal 72a and also be fed to controller 50a from the piston rod 16a of actuator 11a, to obtain indication by the desired location of manual control 51a representative with by the error signal between the actual location of signal 70a representative.Control module 50a produces pressure reference signal 61a on control signal line 52a, this pressure reference signal is applied to each control unit 47a of motor 46a, to regulate machine 32a and mobile piston 14a on required direction.Assumed load 30a moves along the direction of as shown in Figure 3 arrow X, and machine 32a increases capacity, with the pressure in the acquisition reduction of port 26a place, be equivalent to the pressure that set by reference signal 61a, and fluid flows out from chamber 18a.Machine 34a use maximum reference pressure with travelling load 30a and change capacity to keep this pressure.When obtaining desired location, position signal 72a changes and manually controls difference between 51a and the position signal 72a and is reduced to and is roughly zero.Wobbler turns back to zero displaced position gradually, and all can produce error signal at control module 50a from any motion of this desired location, to regulate suitable pressure reference signal 61a and to make load get back to desired location.The capacity of machine 32a reduces with boost pressure thus gradually, and the corresponding capacity reduction of machine 34a, is still in required orientation up to load 30a.

The control configuration of Fig. 1 also is changed, thereby speed controlling is provided, and has wherein limited top speed.For clear, identical assembly refers to the same reference numerals of band suffix " b ".In the embodiment of Fig. 4, be not the position of monitors load as shown in Figure 3, the capacity of

machine

32b, 34b is monitored and as the indication of speed.With reference to figure 4, the manual control at the 51b place provides and the proportional output signal of speed that is obtained, and this output signal generation control signal 52b causes machine 32b to move to motoring mode and reference pressure is reduced to nominal low value.The capacity of machine 32b increases under motoring mode, to reduce the pressure at port 26b place, load is quickened.

Machine 34b, the increase of 32b capacity are equivalent to by controlling the pressure that 51b sets up to the capacity by feedback signal 57b indication.Error signal is removed thus, and the capacity of machine 32b reduces to set up reference pressure.The reference pressure of machine 34b is in maximum value, thereby load is quickened capacity and the output signal coupling of coming from control 51b up to the machine 32b that is indicated by feedback signal 57b once more.Because machine reduces capacity gradually, so wobbler position feedback 57b introduces error signal once more, this error signal can make machine 32b increase capacity, so that reduce pressure.Thereby, obtain stable speed, the intermediate value that it is limited for the machine maximum capacity.This control is very useful for the automated procedure as machine tool drive etc.

With the bilateral actuator above-mentioned linear actuators is described, can be used for one-sided actuator equally but should understand them, promptly piston rod has different areas from a side-prominent and chamber of actuator.Corresponding reference signal 61 can and bar side cavity and piston side chamber between regional difference adjust pro rata, thereby control the motion of cylinder body to be similar to the similar mode of aforesaid way among Fig. 1.

The similar control structure can be used for rotation and drives, as being used for capstan winch or similarly using.This collocation form is presented among Fig. 5, and wherein identical reference character is used in reference to identical assembly of generation, but in order to describe the clear prefix " 1 " that has.A pair of variable capacity hydraulic machine 132,134 hydraulic transmissions ground is connected to fixed capacity rotating machinery 180 by hydraulic line 122,124.Initiatively son 138 is mechanically connected on each machine 132,134, and capstan winch assembly 130 is connected to machine 180.Machine 132,134 is by motor 146,148 controls, and control signal 152,154 is used by control module 150.Mass is static, and each is adjusted member 142,144 and is set at roughly zero capacity, and hydraulic lock is in supply line 122,124.The pressure compensation of machine has guaranteed that the pressure in the system keeps, with the motor locking and suppress the rotation of capstan winch.

Rotation capstan winch 130 has been indicated the reduction pressure that needs to increase capacity under motoring mode to the signal of motor 132 when the signal that has from actuator.When fluid was carried in supply line 122, the control of the pressure compensation of machine 134 was adjusted, pressure is maintained the setting pressure that is controlled that causes 130 rotations of capstan winch assembly.Position as implied above and speed controlling can be used for the motion of control load and it is maintained desired location.In case obtain this position, then error signal removes by the feedback that discharges manual control 151 or release position or speed controlling, wobbler 144,142 turns back to roughly zero position gradually, does not wherein have energy to pass through systems communicate, but load is kept via the pressure of motor both sides.

Therefore as seen, in each of the foregoing description, a pair of pressure compensation variable capacity machines can be used for controlling the operation of actuator.

Pressure compensation allow to utilize minimum energy to keep actuator and by not considering that setting pressure on the actuator floss hole obtains the control that actuator is moved.Need only a machine to be modulated, another machine is then kept setting pressure and is used motive force.The mechanical connection of machine can be used for making energy always to flow out and recover from the fluid of actuator, and may be used on the machine, and motive force is provided.

As mentioned above, the mechanical linkage of

machine

32,34 allows energy under certain conditions to recover.Energy recovers and can strengthen by adopting collocation form as shown in Figure 6.Identical reference character can be used for representing identical assembly, for the clear prefix " 2 " that increases.In the embodiment of Fig. 6, a pair of variable capacity machines 232,234 is connected on the actuator 211, and this actuator 211 is connected with load 230.Each machine 232,234 comprises pressure compensation control and operated by manual control 251 by controlling 250, as mentioned above.Machine 232,234 mechanically links by pair of engaged gears 236, thereby they as one man rotate.Driving to machine is provided by active 236 by train of gearings 280, and train of gearings 280 comprises gear 282,283.

Auxiliary hydraulic pressure driver 284 is connected with gear 283 and provides fluid to auxiliary servo device 276.Driver 284 can be fixing or variable capacity, and if suitable can control by machine 232,234.Train of gearings 280 also comprises the gear 285 that drives extra variable capacity hydraulic machine 286.Machine 286 is connected with hydraulic pressure hydraulic accumulator 288, and this hydraulic accumulator is operable as by the energy that machine 286 stores and exhaust fluid and absorbing is thus come from train of gearings 280 or to train of gearings 280 distribute energy.Provide velocity transducer 290 to be connected with the speed of monitoring train of gearings 280 and with control module 250 interfaces.

In operation, hydraulic accumulator is empty and supposition auxiliary actuator 284 provides stable fluid to flow to servomechanism 276 at first.Mass 230 moves with constant speed under the effect of machine 232,234, and initiatively son 238 provides sufficient energy to satisfy the demands to train of gearings 280.If mass 230 is slowed down with maximum rate, as mentioned above, machine 232 is adjusted into pressure maximum under motoring mode, and produces significant moment of torsion so that driving is 280 acceleration.Originally initiatively son is removed fuel, supposes that it is a compression-ignition engine, and is used for drive machines 284 and is provided fluid to auxiliary servo device 276 by the moment of torsion that machine 232 provides.If moment of torsion can not be absorbed under this mode, then train of gearings will speed up and velocity transducer 290 provides signal to controller 250, to increase the capacity of additional machine 286 under the pump pattern.Therefore machine 286 provides fluid to hydraulic accumulator 288 under the situation that has pressure to exist, its speed is the required speed that can absorb existing moment of torsion and keep train of gearings 280.

Because mass 230 is static, the moment of torsion of train of gearings reduces and speed descends so be provided to.Owing to lack via machine 232 caused energy, control 250 makes machine 286 reduce the action of pump and turn back to and is roughly zero capacity, and energy storage is in hydraulic accumulator 288.Similarly, if between deceleration period, auxiliary servo device 276 needs more energy, and then the speed of train of gearings 280 will reduce and machine 286 is adjusted.The available energy that comes from machine 232 is directed to auxiliary servo device 276 and energy remaining thus again, if present, can be used for hydraulic accumulator 288 is played pump.

If the load that applies by servomechanism 276 continues to increase, then be stored in the required speed that energy in the hydraulic accumulator 288 can be kept train of gearings 280.The load that continues to increase will cause the speed of train of gearings 280 to reduce once more and make controller 250 that extra machine 286 is moved to motoring mode.Available compression fluid is applied to machine 286 in the hydraulic accumulator, to produce pressure and keep required speed thus in train of gearings.The wobbler of machine 286 is modulated, all consumes speed is maintained desired level all energy (or low threshold value) in hydraulic accumulator 288.At this moment, by sub 238 filling fuels of active are satisfied further energy demand.The mechanical connection of the hydraulic accumulator 288 by the machine 286 and modulation that the speed of train of gearings 280 maintains in the required restriction increased the utilization that recovers energy.

Aforesaid system can be incorporated in the control strategy of complex machines more, and shown in Fig. 7 and 8, wherein identical reference character has prefix " 4 " and is used to represent identical assembly.Therefore referring to Fig. 7, vehicle V comprises the chassis structure C that is bearing on the driving wheel W.Superstructure S is positioned at the vertical axis that chassis structure C goes up and can center on the rotating disk T and rotates.Component truss B is pivotally mounted on the superstructure S, is used for the motion of vertical plane.Boom actuator 411 is connected between superstructure S and the component truss B and can operates, and is used for promoting and reducing truss.

Vehicle V comprises active 438 that is connected with hydraulic driving system 410 by train of gearings 480, as showing in more detail in Fig. 8.As can be seen from Fig. 8, can be active 438 of electric notor or internal-combustion engine form input is provided to mechanical gear is 480, this train of gearings 480 transmits drive to a plurality of variable-displacement hydraulic machines 432,432a, 434,434a, 484 and 486.Each hydraulic machine 432,432a, 434,434a, 484 and 486 are variable-displacements and have capacity adjustment member 442,443,444,445 respectively.Machine 432,432a, 434,434a, 484 and 486 are generally adjustable wobbler machine, have tiltable wobbler, and this wobbler acts on the interior pistons of rotary barrel, as top described with reference to previous embodiment.

Driving to boom actuator 411 is provided by manual control 451a by a pair of machine 432,434, and this is flowing of control energy control piston 414 either sides manually, as top described with reference to figure 1 and 2.Similarly, rotating disk T can be rotated motor 480 by manual control 451b and drive, this manual control can with as control a pair of

machine

432a, 434a about the described mode of Fig. 5.Extra machine 486 transmits energy between hydraulic accumulator 488 and train of gearings 480, as described about Fig. 6.

Hydraulic machine 484 is pressure compensated, and as described about Fig. 2, and auxiliary servo device 476 is connected to wheel-drive 502,504,506 and 508 by supply line 500.It all is variable-displacement reversible hydraulic machine device that each wheel-drive 502,504,506 and 508 all drives wheel W and each respectively, has as with reference to figure 2 described control units 547.Each has the accent parts 510,512,514 and 516 by respective valves control.Hydraulic machine 510-516 has and is similar to the such structure of

machine

32,34, and does not need to be described in detail.

The capacity of each driver 502-508 is all controlled by wobbler position signal 461, and this signal produces by control module 450.Each driver 502-508 also provides rotational speed signal 458 on signaling line 452, be used to monitor the operation of each machine.

The operator is provided to control module 450 to the control of transmitting via

manual control

451c, 451d, 451e.Manually the direction and the speed of the propelling force of control 451c control vehicle V are controlled the brake of 451d control vehicle V, control 451e steering vehicle V.These all are typical control and should understand and also can adopt other shared interfaces.

Suppose that initial vehicle is in static and truss is locked in lower position, the operation to hydraulic driving system is described in this case.Stationary vehicle, the capacity of each machine 432,432a, 434,434a is essentially zero capacity, and keeps maximum set pressure.Wheel-drive 502-508 is arranged on minimum capacity similarly, and carrying zero moment of torsion, and machine 484 is essentially zero capacity, keeps the pressure maximum in the pipeline 500.In fact, this setting is enough to be used in any leakage in the replenishment system simply, but can not produce vehicle movement.

Actuator 488 discharges fully and the capacity of extra machine 486 is minimum.Each machine 432,432a, 434,434a, 484 and 486 are minimum, and active 30 is rotating machinery simply, can not produce any output, and therefore is in the minimum power demand.

In order to start the motion of vehicle V, the operator moves control 451c and provides appropriate control signals 453c to control module 450 on required moving direction.Usually, this is a scaling signal, has not only indicated direction to also have at the moment of torsion at wheel place and has imported, and moment of torsion will determine the movement velocity of vehicle.Control module 450 provides control signal 452 to wheel-drive 502-508, obtaining torque setting (dislocation), corresponding to from controlling 450 and the input signal that comes.This will be the ratio torque setting, indicate corresponding proportional machine capacity.Quicken for maximum, this is with corresponding maximum dislocation.When the capacity of wheel-drive 502-508 under the control of each wobbler 510-516 increased, the pressure in the supply line 500 reduced, and the pressure compensation that causes machine 484 is to increase the capacity of this machine.Make wheel W rotation and propelled vehicles by the mobile final moment of torsion that causes of the fluid of pipeline 500 from driver 502-508.

The capacity of wheel-drive 502-508 continues to increase, and has obtained and required torque is sent to each and takes turns up to the required capacity of wobbler position feedback 457 indications.In this time, the pressure in the pipeline 500 will be kept by the capacity that increases machine 484 under pressure compensation control.Unless be interrupted, by adjusting control 451c or increase the load of vehicle, vehicle V will speed up up to machine 484 when external load and available torque are mated and reaches balance.

When vehicle obtained required speed, the operator discharged control 451c with the capacity that reduces wheel-drive 502-508 and reduce moment of torsion subsequently, to suppress further to quicken and keep required speed.Machine 484 reduces the device capacity, keeps flowing by wheel motor simultaneously pressure is maintained maximum value.Reach such steady state: be fed to the moment of torsion of wheel W and the load on the vehicle V and be complementary.Under certain conditions, for example descending is advanced, and does not need moment of torsion to keep required speed and wheel-drive 502-508 and machine 484 and returns substantial zero capacity.Under this condition, vehicle is advanced simply and is not had net power to be fed to wheel 14.

In order to make vehicle V brake, brake control 451d is started (if suitable its can be incorporated among the control 451c).The application of brake control 451d produces and control 450 proportional signal 453d, and this signal can be adjusted to each wheel-drive the pump pattern with selected capacity.Wobbler 510-516 moves the increase that focuses on the pump pattern and cause the pressure the pipeline 500 from motoring mode thus.Machine 484 initial its capacity of reduction are also concentrated under pressure controlled effect subsequently and are entered motoring mode, to keep maximum set value.Wobbler feedback signal 457 remains on wheel-drive by the indicated capacity of brake control 451d also passes through machine 484 pumping fluid under pressure maximum.Carry out the required moment of torsion of this operation and carry and therefore make vehicle V brake by the momentum of vehicle.Machine 484 is adjusted to motoring mode will cause energy to be fed to train of gearings 480 from machine 484.

The energy that is fed to train of gearings 480 causes comprising that initiatively the train of gearings of son is quickened.The rotational speed of train of gearings is monitored by velocity transducer 490 and the increase of this speed detects by control module 450.This can regulate moving to the pump pattern the machine 486 that is associated with hydraulic accumulator 488, and under pressure to hydraulic accumulator 488 accommodating fluids.The dislocation of machine 486 is controlled, maintains setting speed with the speed with train of gearings 480.Hydraulic accumulator recovers to hold power by the energy that brings owing to vehicle brake thus.

The effect of brake is depended in the storage of energy, and machine 486 modulation capabilities maintain desired level with the speed with train of gearings 480.

When having removed brake control 451d and having used speed controlling 451c again, wheel drive 502-508 is adjusted to motoring mode again and machine 484 is returned to the pump pattern, to keep the pressure in the pipeline 500.

When machine 484 moved and supplies energy into pipeline 500, the perceived and machine 486 of the reduction of the rotational speed that train of gearings 480 is initial was adjusted to motoring mode, so that energy is fed to train of gearings 480 from hydraulic accumulator 488.Therefore during braking, be stored into energy in the hydraulic accumulator 488 and be used in system of vehicle transmission in the further acceleration cycle process.When having exhausted hydraulic accumulator 488, it is modulated that the reduction of engine speed will be noted and be fed to the fuel of engine, constant so that speed is maintained.

Truss B operates by the modulation of machine 432,434.In order to extend boom actuator 411, control signal is sent to control 450, indicated pressure and direction from operator 451a.The reference signal 461 that is applied to the pressure control 463 that is associated with machine 432 is adjusted in control 450 subsequently.This has caused machine 432 increase capacity and therefore described pressure is reduced to low reference pressure under motoring mode.Machine 434 is made response by its pressure control, thus increase it under the pump pattern capacity and extend cylinder body 411, as mentioned above.The speed of motion can be adjusted by the modulation of adjusting member 451a, to obtain required movement rate.

When reducing truss B, also there is opposite operation, wherein increase the capacity of machine 434 under the motoring mode.When truss B reduces, also exist positive energy to recover, can obtain from fluid, and this is passed to train of gearings 480 by discharge the machine 434.Again, if energy transfer is enough to increase the rotational speed of train of gearings, then hydraulic accumulator 488 can be supplied by the operation of machine 486, and on the contrary, promoting cycle period, the fluid that is stored in the hydraulic accumulator 486 can be fed to train of gearings 480 by machine 486, with the rotation of auxiliary machinery 434 or machine 484.

Similarly energy transfer can obtain from the rotation of superstructure S, and wherein the inertia of superstructure can be used for storing energy in the hydraulic accumulator, for follow-up use.Therefore in its basic operation, should notice that hydraulic transmission 410 is operable as energy from different exhaustion point transmission, and when needed by using hydraulic accumulator 488 to preserve energy.Although for rotating disk T has shown rotating driver 480, being similar to 502 driver can use under identical mode.

Indivedual controls of wheel W also allow the control by the rotational speed of monitoring individual wheels 14, the individual wheels of being undertaken by signaling line 458.Wheel W is when engaging such as ice or the such following friction surface of mud therein, and during acceleration or braking, its speed will be different from other wheel W.Speed difference is noted and the capacity of this machine correspondingly reduces by controlling 450, is applied to moment of torsion on the particular wheel with reduction.Under extreme conditions, the capacity of machine is reduced to zero, advances thereby specific wheel can be considered to be under the situation that does not have torsional interaction.Yet, under this condition,, the pressure in the pipeline 500 realizes the wheel balance thereby being maintained, maintain these traction of taking turns or braking effects thus.In case wheel slows down, application of torque again then.This allows to implement traction control and ABS.

Be applied to the moment of torsion of each wheel on the same axle by adjustment, also can be incorporated in the driving to vehicle indivedual drivings of wheel.The rotation of control 451e produces a signal, and this signal is to need a pair of speed of taking turns to differ from one another to be rotated.Thus, need the capacity and the moment of torsion of the outboard wheel of higher rotational to increase, provide by corresponding reduction to nearside wheel.Because the pressure compensation of machine 484, be applied to each pressure of taking turns keep constant and thereby the acceleration of outboard wheel takes place, cause the driver behavior of vehicle under not via machine 484 energy-producing situations.

Claims

1. hydraulic driving system, comprise: actuator, has a pair of chamber, this is driven member to chamber and separates and be set to motive force to be applied on the described driving component in the opposite direction, each member all with a pair of variable capacity machines in separately one be connected, one of them variable capacity machines can be operated under the pump pattern to supply fluid in the chamber, and another variable capacity machines can be operated under motoring mode to consume from the fluid of another discharge of described chamber at least, each described machine has pressure compensation control, keep in the described chamber separately predetermined pressure to regulate described machine, and be operable as described predetermined pressure at least one that is modulated at described machine, and change the motive external control that acts on the described driving component thus.

2. hydraulic driving system as claimed in claim 1, wherein each described machine all is reversible, so that operating under the pump pattern or under motoring mode, and, another of described machine be operable as one of them of under the pump pattern, regulating described machine when being in motoring mode described control of following time.

3. hydraulic driving system as claimed in claim 2, wherein by being reduced in the pressure at the described machine place that is conditioned under the described motoring mode, described predetermined pressure is modulated in described control.

4. hydraulic driving system as claimed in claim 3, wherein during the pressure of the machine of living under being reduced in described motoring mode, described control maintains the predetermined pressure in the described machine of regulating under the described pump pattern.

5. hydraulic driving system as claimed in claim 3, each of wherein said machine all are variable-displacement wobbler machines.

6. hydraulic driving system as claimed in claim 1, wherein said machine mechanically connects, to transmit energy between them.

7. hydraulic driving system as claimed in claim 1, described another machine that wherein can operate under motoring mode is mechanically connected on the extra hydraulic machine, with to the hydraulic accumulator accommodating fluid.

8. hydraulic driving system as claimed in claim 7, wherein said extra hydraulic machine is a variable capacity machines.

9. hydraulic driving system as claimed in claim 8, the capacity of wherein said extra hydraulic machine can be adjusted to absorption from described another machine and the energy that comes and keep the scheduled operation condition of described another machine.

10. hydraulic driving system as claimed in claim 9, the capacity of wherein said extra machine is adjustable, with will be from described hydraulic accumulator and the energy transport of coming to described mechanical connection to keep described operational condition.

11. hydraulic driving system as claimed in claim 10, a wherein said machine, described another machine all mechanically is connected with described extra machine, transmits between them to allow energy.

12. hydraulic driving system as claimed in claim 11, wherein each described machine all is reversible variable capacity machines.

13. hydraulic driving system as claimed in claim 12, wherein auxiliary machinery is mechanically connected to described machine, so that auxiliary servo to be provided.

14. hydraulic driving system as claimed in claim 12, wherein said auxiliary servo are transmission.

15. hydraulic driving system as claimed in claim 10, wherein said transmission comprise the hydraulic drive unit that is mechanically connected to the reversible variable capacity machines on the described extra machine and hydraulically is connected to described machine.

16. hydraulic driving system as claimed in claim 15, wherein said reversible variable capacity machines is pressure compensated, to maintain the pressure in the hydraulic pressure connection between described machine and the described hydraulic drive unit.

17. hydraulic driving system as claimed in claim 16, wherein said driver element are variable capacity, changing the moment of torsion under described predetermined pressure, carry, and its capacity of described control break.

18. hydraulic driving system as claimed in claim 17, wherein said driver element is reversible.

19. hydraulic driving system as claimed in claim 18, wherein a plurality of driver elements are connected to described reversible variable capacity machines.

20. hydraulic driving system as claimed in claim 19, wherein each described driver element provides rotation output, monitor the relative rotational of described output and adjust described capacity with described control, maintain defined ratio with described speed with described output.

21. hydraulic driving system as claimed in claim 20 wherein reduces output speed by the capacity that reduces the respective drive unit, to reduce the moment of torsion that is produced.

22. hydraulic driving system as claimed in claim 20, wherein said ratio changes by described control.

23. hydraulic driving system as claimed in claim 22, wherein said ratio changes by importing to the outside of described control.

24. hydraulic driving system as claimed in claim 18, wherein said driver element is reversible by use outside output to described control.

25. hydraulic driving system as claimed in claim 1, wherein oil hydraulic motor is used to change the capacity of described machine, and the valve of the signal by the difference between the pressure in described predetermined pressure of response representative and the described chamber is controlled described motor.

26. hydraulic driving system as claimed in claim 25, wherein said valve applications is represented the feedback of the condition of described valve, to revise described signal.

27. hydraulic driving system as claimed in claim 25, during wherein in described pressure increase and near described predetermined pressure, described signal is revised in described control.

28. hydraulic driving system as claimed in claim 27, described signal is revised in wherein said control, to reduce the response of described valve.

Monitor the position of described wobbler and thereby adjust the modification of described signal 29. hydraulic driving system as claimed in claim 28, wherein said machine are rotating machinery and described control.

30. hydraulic driving system as claimed in claim 29, the beginning of wherein said modification occur in when described speed increases than the big difference place.

31. hydraulic driving system as claimed in claim 28, wherein said machine are wobbler rotating machinery and described control monitoring wobbler position and thereby adjust the modification of described signal.

32. hydraulic driving system as claimed in claim 31, wherein said modification begin to occur in when described wobbler position increases than the big difference place.

33. hydraulic transmission, comprise first variable capacity hydraulic machine that is driven by active, at least one variable capacity hydraulic drive unit, the hydraulic tubing that is connected with described driver element with described first machine, pressure compensation control, can on described first machine, operate changing its capacity and in described pipeline, to keep predetermined pressure, and external control, its capacity can be operated and change to this external control to change the moment of torsion that produces by described driver element on described driver element.

34. hydraulic driving system as claimed in claim 33, wherein said first machine and driver element are reversible, and thereby described external control can be operated the capacity that changes described unit: from consuming the condition changing of fluid to the condition to described line transportation fluid described pipeline, described pressure compensation control causes the described first machine turning operation pattern thus, to keep described predetermined pressure.

35. hydraulic driving system as claimed in claim 34, first machine is mechanically connected to extra variable capacity machines shown in it, thereby provides fluid to hydraulic accumulator.

36. hydraulic driving system as claimed in claim 35, the capacity of wherein said extra hydraulic machine can be adjusted to absorption from described another machine and the energy that comes, and keep the scheduled operation condition of described another machine.

37. hydraulic driving system as claimed in claim 36, the capacity of wherein said extra machine can be adjusted to from described hydraulic accumulator and the energy transport of coming to described mechanical connection, to keep described operational condition.

38. hydraulic driving system as claimed in claim 34, wherein a plurality of driver elements are connected to described pipeline, and wherein each described driver element provides rotation output and described control to monitor the relative rotational of described output and adjust described capacity, maintains defined ratio with the described speed with described output.