CN101535110B

CN101535110B - Continuously variable transmission

Info

Publication number: CN101535110B
Application number: CN200780041297.4A
Authority: CN
Inventors: 克里斯托弗·约翰·格林伍德
Original assignee: Torotrak Development Ltd
Current assignee: Allison Transmission Inc
Priority date: 2006-09-26
Filing date: 2007-09-24
Publication date: 2014-04-09
Anticipated expiration: 2027-09-24
Also published as: GB2455030A; KR101440848B1; GB2455030B; GB0618929D0; JP2018200115A; KR20090064590A; JP2010505074A; JP2015007481A; CN101535110A; WO2008038043A3; JP2017062039A; DE112007002280B4; DE112007002280T5; GB0904809D0; KR20140063777A; WO2008038043A2; JP6926379B2

Abstract

The invention is concerned with control of a continuously variable vehicle transmission. The transmission in question is to have a variator (10) which is coupled between a rotary transmission input (32) and a rotary transmission output (46), to provide continuous variation in a transmission drive ratio, via a launch device such as a clutch (62; 68). The variator and the launch device are constructed and arranged to exert a required torque, defined by an input signal. In accordance with the invention, the same control signal is used to control both the variator torque and the torque capacity of the launch device. In such an arrangement, vehicle launch (i.e. moving away from rest) can be controlled in a straightforward manner by progressively raising the relevant control signal, preferably a hydraulic pressure signal. Further independent claims are including for applying traction load to races (20, 22) of the variator and for a method setting torque of the launch device (62; 68) higher than torque of the variator (10).

Description

Positive infinite variable driving device

Technical field

The present invention relates to positive infinite variable driving device (continuously variabletransmission, toric transmission).One aspect of the present invention relates to the control to the launch device in this driving device (launch device) and change-speed box (variator).

Background technology

In any positive infinite variable driving device, all there is the device of the stepless variation that realizes transmitting ratio.This device is called to " change-speed box " here.

In vehicle transmission gear, be necessary for " starting " (that is, vehicle being accelerated so that the state that its disengaging is halted and set out) ready.About this point, some drivings device depend on " launch device " used such as power-transfer clutch.When stationary vehicle, power-transfer clutch is used for driving engine separated with driven wheel.In order to make vehicle derailing halt the state of setting out, move, driving device is placed in to low gear, set driving engine to produce suitable moment of torsion, and engage gradually launch device, thereby increase the speed of driven wheel.Yet the management of this process may more complicated.

In positive infinite variable driving device technology, a kind of known alternative is that the output of change-speed box is applied to planet mixing gear (epicyclic mixing gear), this makes the state that reaches so-called " geared neutral " become possibility, wherein driving device provides infinite speed effectively, and does not need physically that driving device output is separated with driving device input.In such driving device, do not need such launch device.By transmission ratio (variator ratio) is removed and has been realized and having started simply from " geared neutral " value.Yet this driving device must relate to the structural complexity of gear transmission aspect, and relate to some difficult problem about controlling.

To distinguishing between the change-speed box of " transmitting ratio is controlled (ratio controlled) " and the change-speed box of those " moment of torsion controls ", be useful.The change-speed box that transmitting ratio is controlled have some for the transmitting ratio that regulates himself to reach the physical mechanism of setting value.For example, known " semi-circular " rolling traction type (" half-toroidal " rolling-traction type) change-speed box is typically used a kind of like this valve, a part for this valve (for example, spool)) be operationally attached to variator roller, the position of these rollers is corresponding with transmission ratio, for example, and another part of this valve (, forming the removable sleeve pipe of valve port) moves to the transmission ratio place of setting.The state of valve depends on the relative position of these two parts, and this valve control is applied to the pressure that acts on the piston/cylinder arrangements in variator roller.Result is to obtain a hydro-mechanical feedback loop, and wherein valve constantly compares transmission ratio and expectation value, and then regulates transmission ratio so that it reaches this expectation value.The electronics package being associated is selected the transmission ratio of expectation and the signal that represents this transmission ratio is sent to driving device.

In the change-speed box of controlling at moment of torsion, not for transmission ratio being adjusted to this physical unit of expectation value.The control signal of the moment of torsion that alternatively, representative of change-speed box reception will produce.At the publication number such as Torotrak Development Limited (Torotrak Development Co., Ltd), be that in the situation of the known loopful shape change-speed box described in International Patent Application PCT/GB2005/03098 of WO 2006/027540, this signal is taked the form of hydraulic pressure.In response to this signal, change-speed box produces the moment of torsion needing in its I/O place.Can allow the actual transmission of change-speed box than automatically changing, to adapt to the velocity variations that this torque applications is caused in relevant inertia (relevant inertia).Therefore,, at the pusher side/input side that starts of driving device, the moment of torsion being produced by change-speed box and the summation of engine output torque have determined to act on the clean moment of torsion on the rotor inertia of driving engine and associated components, and have determined thus engine acceleration.At the wheel side/outgoing side of driving device, the moment of torsion being produced by change-speed box has determined can be used to the clean moment of torsion to vehicle acceleration itself with the summation of the moment of torsion applying due to the outside of brake, road gradient etc.In the consequential velocity variations of input and output place, follow the variation of transmission ratio, and change-speed box automatically adapts to these variations.

At known moment of torsion, control in the loopful shape rolling traction change-speed box of type, change-speed box is used for producing " reaction torque (the reaction torque) " corresponding to control signal.Reaction torque is the summation of the moment of torsion of change-speed box input and output place.On a 50-50 basis, reaction torque can be defined as working to prevent to change-speed box mount pad (mounting) moment of torsion of its rotation.

Typically, change-speed box depends on for the traction between the turning unit of transferring power (drive drives).For example, in the situation of ring raceway (toroidal-race) rolling traction change-speed box, the roller variator races recessed with annular frictionally engages, and by this frictional engagement, power is passed to change-speed box output with variable-speed ratio from change-speed box input.For the traction between roller and raceway is provided, must make their bias voltages towards each other.For produce the biasing force of traction at change-speed box, at this, will be called " drawbar load ".In principle, can use fixing drawbar load.Yet this need to be set as drawbar load sufficiently high value to be avoided the excessive slip between all situations lower roller and raceway.Therefore, selected traction load value will be excessive for most applications, thereby causes the too early wearing and tearing of lower energy efficiency and rolling member.Therefore, conventionally make drawbar load along with the moment of torsion applying as one man changes.More specifically, in the change-speed box of controlling at moment of torsion, drawbar load typically changes pro rata with reaction torque.This has advantages of provides constant traction coefficient.Sometimes must regulate very rapidly drawbar load, in the situation of unexpected " transition " event (such as emergency brake), slide preventing.In some existing systems, this realizes by applying drawbar load with hydraulic efficiency gear.Particularly, the hydraulic pressure that is supplied to control plunger (these pistons are attached to variator roller) is also led to the hydraulic actuator for generation of drawbar load, thereby the power and the drawbar load that are applied to variator roller are as one man changed.

In such hydraulic efficiency pressure system, the motion of hydraulic pressure " terminal block (end stop) " with limiting transmission roller is provided conventionally, thereby prevents these variator roller to drive and depart from raceway.For example, this can realize by such layout: during in above-mentioned piston one terminal that arrives its predetermined stroke, fluid egress point on the hydraulic actuating cylinder that comprises this piston is by this piston sealing itself, and the pressure increase producing in hydraulic actuating cylinder is used for stoping the motion of piston.The pressure increasing is also applied to traction load actuator, if coordinating the respective change by drawbar load, the variation of the reaction torque producing due to the effect of terminal block (if do the used time at block, do not produce slip, the respective change of drawbar load is necessary so), the pressure increasing so must be applied to traction load actuator.

Summary of the invention

The object of the present invention is to provide a kind of improved CVT.More specifically (but needing not to be uniquely), the object of the present invention is to provide the simple CVT of a kind of structure and mode.

According to a first aspect of the invention, there is a kind of vehicle positive infinite variable driving device, it comprises the rotation input that can be connected to rotating driver, can be connected to the rotation output of wheel, be connected between rotation input and rotation output so that the change-speed box of variable transmission ratio to be provided, and be arranged to optionally connect/separating rotary and transfer into the launch device with rotation output, change-speed box is constructed and is arranged to apply the moment of torsion needing, and launch device is constructed and is arranged to provide torque peak (the torque capacity needing, torque capacity), this driving device is characterised in that, this driving device comprises control setup, this control setup is sent to change-speed box to set the moment of torsion needing by identical control signal, and be sent to launch device to set its torque peak.

The torque peak of launch device (this device can adopt the form of power-transfer clutch) is the torque peak that can be passed to change-speed box and be determined by the degree of engagement of power-transfer clutch, for example, in hydraulic-driven power-transfer clutch, by the fluid pressure applying, determined.By using single signal co-controlling power-transfer clutch and transmission torque, not only for driving device, control needed equipment and simplified significantly, and the control of launch process is more prone to.

According to a second aspect of the invention, have a kind of change-speed box, it comprises: the raceway that at least one pair of part annular is recessed, and these raceways are common to be limited one the variator cavities of annular and they is installed in a common variator axis and rotates substantially, and at least two rollers, these rollers are arranged between raceway with running on the recessed surface of the part annular at raceway and thus with transmission ratio transferring power between raceway, these rollers are installed by this way, allow them to tilt to change raceway axis with respect to the degree of dip of variator axis, thereby and the stepless change of permission transmission ratio, this change-speed box is characterised in that, one of them raceway of change-speed box is attached to an adapter shaft by mechanical traction force-input device, this mechanical traction force-input device had both been used for transmitting torque between adapter shaft and variator races, also be used for applying drawbar load power (this power is the function of the moment of torsion that is passed) on raceway, drawbar load power is ordered about variator races and is engaged with roller, to provide transferring power needed traction, and it is characterized in that, this change-speed box comprises the mechanical meeting device (mechanical abutment) that restriction roller tilts.

The combination of mechanical traction force-input device (replacement hydraulic efficiency gear) and mechanical end block (replacing hydraulic pressure terminal block) is highly beneficial.The drawbar load that machinery produces can change along with the speed of needs.Because this drawbar load produces in response to acting on the moment of torsion on associated transmissions raceway, rather than produce in response to being applied to the power of roller, so the variation of the transmission torque being produced by the effect of terminal block automatically causes the suitable variation of drawbar load, and does not need terminal block itself to be operatively attached to traction force-input device.

According to a third aspect of the invention we, there is a kind of method of controlling vehicle positive infinite variable driving device, this driving device comprises: can be connected to the rotation input of rotating driver, can be connected to the rotation output of wheel, be connected between rotation input and rotation output so that the change-speed box of variable transmission ratio to be provided, and optionally connection/separating rotary transfer into and the launch device of rotation output, this control method comprises: control this change-speed box so that the reaction torque of expectation to be provided, and as one man control the torque peak of launch device with exercised over variator reaction torque, so that the moment of torsion that is applied to launch device by change-speed box is always less than the torque peak of launch device.

Therefore the coordination of, having simplified the torque peak of reaction torque and launch device is controlled.In addition, by little by little increasing the torque peak of exercised over variator reaction torque and launch device, the very favorable method that this method is started management is more convenient, the torque peak of launch device always surpasses the moment of torsion that is applied to this launch device by change-speed box, till stopping at least to the slip of launch device, thereby until then, driving device one keeps its fastest ratio straight through be passed to (refer to) its moment of torsion by launch device.

Accompanying drawing explanation

Referring now to accompanying drawing, only in the mode of example, specific embodiments of the invention are described, in the accompanying drawings:

Fig. 1 is the schematic diagram of positive infinite variable driving device (" CVT ") constructed according to the invention;

Fig. 2 a is the more detailed view of the traction force-input device using in CVT seen along radial direction;

Fig. 2 b is the transparent view of variator races, wherein shows the back side of this raceway;

Fig. 3 is the schematic diagram of the hydraulic control device of CVT; And

Fig. 4 shows some parts of the change-speed box using in CVT of seeing along axial direction.

The specific embodiment

Fig. 1 shows the CVT of the change-speed box 10 that uses ring raceway rolling traction type.More specifically, this is the loopful shape change-speed box of a two-chamber.This change-speed box has the first input raceway 12 and the second input raceway 14, and these two raceways have the recessed surface 16,18 of semi-circular separately.Is the first output raceway 20 and the second output raceway 22 between these input raceways, and these two raceways also have the

recessed surface

24,26 of semi-circular separately, thereby between the first input raceway 12 and the first output raceway 20, be formed with the first annular chamber 28, and be formed with the second annular chamber 30 between the second input raceway 14 and the second output raceway 22.These raceways have the common axis of rotation line being limited by main shaft (by 32 schematically indications), and these raceways rotate around above-mentioned main shaft.

Each

chamber

28,30 all comprises set of

rollers

34,36 separately.Each roller is all mounted to around roller axis such as 38 and rotates, and each roller all moves on the annular surface of input raceway associated with it and output raceway, so that power is transmitted to another raceway from a raceway.The mount pad of these rollers (not shown in Fig. 1, but will briefly describe) also allow roller to change its degree of dip according to the variation of transmission ratio, the angle between roller axis 38 and main shaft 32 changed.Main shaft 32 is as the rotation input of change-speed box, and connect and (directly to connect or by intermediate gear driving coupling, not shown) to the rotating driver such as driving engine, in this specific embodiment, it takes the form of combustion engine (schematically illustrated by 40).The dissimilar rotating driver of use such as electrical motor, external combustion engine etc. also can be realized equally well the present invention.The

input raceway

12,14 of change-speed box is fixed to main shaft 32, thereby along with main shaft rotates together, and therefore by driving engine 40, driven.

Output raceway

20,22 can rotate with respect to main shaft 40.In the illustrated embodiment, this is realized by

cylindrical bearing

42,44, and these output raceways are arranged on respectively on main shaft 32 by cylindrical bearing.By

roller

34,36, power is passed to output raceway 20,22 (or vice versa, under " hypervelocity (over-run) " state) with variable-speed ratio from input raceway 12,14.

Output raceway

20,22 can operationally be attached to the final transmission 46 of leading to wheel, and this will be described briefly.

In the change-speed box 10 illustrating, by machinery (non-hydraulic pressure) traction force-input device 48, provide drawbar load, this traction force-input device is used for the proportional power of the output torque to change-speed box (" drawbar load ") bias

voltage variator races

12,14,16,18 so that these raceways engage with variator roller 34,36.This realizes away from each other by ordering about two innermost raceways (in the illustrated embodiment, these two raceways are

output raceways

20,22).By

roller

34,36, drawbar load is passed to outmost raceway (in the present embodiment, these outmost raceways are input raceways 12,14), and these raceways guide power into again main shaft 32, main shaft is in tension state thus.By by this way drawbar load being guided into main shaft 32, without any need for the thrust baring of opposing drawbar load.

Traction force-input device 48 is used simple slope apparatus (ramp arrangement) to transmit output torque, and this slope apparatus produces the drawbar load along axial direction, this drawbar load be passed moment of torsion function (and more specifically, in the present embodiment, with to be passed moment of torsion proportional).

Fig. 2 a and Fig. 2 b have illustrated the structure of traction force-input device 48.Output driven gear 50 is mounted to the back side of output raceway 22 regularly.On surface at it away from output raceway 22, this output driven gear 50 has one group of ramp-like recesses, as shown in dotted line (phantom) 52 in Fig. 2 a.Output raceway 20 has corresponding one group of ramp-like recesses 54 on the back side of himself, in Fig. 2 b, illustrates best.When the circumferential direction in Fig. 1 is seen, these recesses 52,54 have the cross section of part circular, and to hold roller 56, these rollers form ball in this embodiment.When seeing along radial direction, these grooves 52,54 seem to have the shape of shallow " V " shape.As shown in Figure 2 a, when the darkest regional alignment of groove 52,54, output driven gear 50 is minimum with the interval of output raceway 20, thereby these balls 56 will himself be positioned in these regions.Yet, when the output of needs change-speed box maintains a moment of torsion, consider what's going on.It should be noted, output raceway 20 can rotate with respect to output driven gear 50 by bearing 42,44.Because output torque causes the relative rotation of these parts, so the darkest region of recess 52,54 is no longer aimed at, and these balls 56 are advanced (ride on) on " V " shape recess thus, thereby thereby force output raceway 20 away from output driven gear 50 and produce the drawbar load needing.When the drawbar load producing by be passed equilibrium of torques time, this relatively rotates and stops.Therefore, as previously mentioned, drawbar load is the function of output torque.The exact nature of this function depends on the structure of recess 52,54, but in the illustrated embodiment, drawbar load and output torque are proportional.

Shown driving device can provide D Drive gear (forward gear) and reverse gearwheel (reverse gear) (in other words, its can reverse the hand of rotation of final transmission 46).This provides two paths to realize by the power output for from output raceway 20,22.First path is through being formed on first group of tooth 58 on output driven gear 50, output driven gear is by messenger chain driving chain gear (chain gear) 60, for the sake of clarity, in Fig. 1, omitted messenger chain, but messenger chain moves in tooth 58 and sprocket gear 60.And sprocket gear 60 is operationally attached to a side of forward gear clutch 62, the opposite side of forward gear clutch is operationally attached to final transmission 46.The second path that is used for obtaining power output is through being formed on second group of tooth 64 on output driven gear 50.These teeth 64 and gear 66 engagements, this gear 66 is operationally attached to a side of reverse clutch 68, and the opposite side of reverse clutch is operationally attached to final transmission 46.It should be noted, for the

first path

58,60,62 of obtaining power output because it uses chain transmission, so the reversing of hand of rotation is not provided.The

second path

64,66,68 that is used for obtaining power output is because it uses a pair of gear, so produce the reversing of direction.Thus, the joint of forward gear clutch 62 makes final transmission produce rotation along a direction, and the joint of power-transfer clutch 68 makes final transmission produce rotation along contrary direction.It should be noted, in this specific embodiment, forward gear clutch 62 and reverse clutch 68 are constructed to prevent the mode that they engage simultaneously.

Final transmission 46 comprises the wheel word 70 that finally leads to wheel (not shown).

As noted above, in Fig. 1, omitted the mount pad for roller 34,36.A kind of suitable form of mount pad has been shown in Fig. 4.In this figure, in

variator races

12,14,20 or 22 can be seen, two

rollers

34 or 36 can also be seen.Their position changes by controlling lever 72, and this control lever is pivotably mounted on fulcrum 74, and fulcrum is contained in the groove 76 of controlling lever.Control lever and have a radially-protruding throw of lever 78 substantially, this throw of lever and crossbeam 80 are integrally formed to form inverse-T-shaped.Spherical coupling (the ball coupling) 82,84 that is positioned at the relative end of crossbeam 80 connects crossbeam with corresponding roller bracket (roller-bearer) 86,88, roller bracket carries and be rotatably mounted corresponding roller.Should also be noted that two

spherical couplings

82,84 not in common sagittal plane (although can't see) in Fig. 4.In Fig. 1, the sagittal plane of annular chamber 30 centers is indicated by dotted line 90.Two

spherical couplings

86,88 leave separately this centre plane 90 and arrange and the opposite side in this centre plane on so that the line from the center of each spherical coupling to each

roller

34,36 center tilts towards this sagittal plane.This degree of dip is known as " kingpin caster angle (castor angle) ".When control lever 72 moves, from accompanying drawing, it is evident that, two rollers all correspondingly deasil or widdershins move around the axis of main shaft 32.When roller moves like this, it is subject to the domination (in mode known to those skilled in the art) of the steering-effecting of variator races.Thereby, two rollers all relatively aforesaid, through the line/axis of spherical coupling center and roller centre, tilt.The steering-effecting acting on roller always trends towards making it to form a leaning angle, wherein the axes intersect of the axis of roller and main shaft 32.Due to kingpin caster angle, they always can find provides this crossing leaning angle.Result is that the inclination of roller (and transmission ratio thus) is the function of controlling the position of lever 72.

Importantly, the load being produced by each roller equates, and in the device of Fig. 4, controls lever 72 and along moving of the cardinal principle being limited by groove 76 direction radially, allowed the equilibrium of roller load.

Use actuator 92 that controlled bias power is applied to throw of lever 78.In the present embodiment, actuator 92 is double-acting hydraulic apparatus.In other words, actuator receives two relative hydraulic pressures, and its power applying is determined by the poor of these two pressure, thereby it can shift to left side or shift to right side in Fig. 4.It is also noted that, with single actuator, control two

variator cavities

28,30 lever 72 separately in the present embodiment.Although can't see the second control lever in Fig. 4, it should be understood that bar 94 leads to another lever from a control lever 72, and the piston 96 of actuator 92 connect the so far mid point of bar pivotly.Therefore, the position of piston 96 is corresponding to the position of the mid point of bar, but two relative positions of controlling lever can change a little, because need the roller between two chambeies of balance to load.

The hydraulic efficiency gear that is used for controlling CVT is described referring now to Fig. 3.In this figure, frame 98 schematically shows for the device of the hydraulic fluid of adjustable pressure is provided.For those skilled in the art, the suitable means that realize this object are known.This pressure leads to change-speed box change-over valve 100, and by this change-over valve, pressure can be applied to the either side of piston 96, to promote to control lever 72 in a direction or another direction.In Fig. 3, show a tapping equipment (exhaust) that leads to fuel tank 102 from piston low pressure side, although all become in practice emptyly for fear of relevant chamber, alternately, tapping equipment also can lead to low pressure source.Actuator 92 is controlled lever 72 to two and is applied power, and the size of this power is determined by pressure source of supply 98, and the direction of power is controlled by change-speed box change-over valve 100.By regulating this power, can control exercised over variator reaction torque.

Pressure from source of supply 98 also leads to power-transfer clutch selector valve 104.This valve is used for above-mentioned hydraulic pressure to be optionally applied to forward gear clutch 62, or is applied to reverse clutch 68.Inactive clutch is discharged to fuel tank 102 by identical valve.Thus, power-transfer clutch selector valve 104 determines that driving device is running or turn round under reverse gear state under D Drive state, and the power that pressure source of supply 98 is determined when effective power-transfer clutch engages, and determines thus the torque peak of effective power-transfer clutch.When vehicle is during in neutral gear, pressure source of supply 98 and disconnecting valve 105 between power-transfer clutch selector valve 104 are used for optionally separated these parts.

As noted above, some are set conventionally and install to limit minimum and maximum transmission ratio.There is no these whens device, will have

roller

34,36 over-tiltings to such an extent as to leave the danger of

variator races

12,14,20,22, thereby there is potential catastrophic consequence.As noted above, in the prior art this " terminal block " typically the mode with hydraulic pressure realize.Yet, of the present invention, illustrate in embodiment, when roller moves, can place simple electromechanical stop.Particularly, these stop limits are used for controlling the motion of the

single actuator

92,96 of all rollers.In principle, block can be taked many multi-form, but it is shown as the energy disperser 106,108 in actuator 92 in Fig. 3, and when piston 96 arrives the terminal of its strokes, this energy disperser is butt piston simply.

The area of the piston in the area of piston 96 and forward gear clutch 62 and reverse clutch 68 (be can't see to latter two piston in accompanying drawing, and the structure of suitable power-transfer clutch is known for a person skilled in the art) be selected to and guarantee that the torque peak of effective power-

transfer clutch

62,68 surpasses the output torque of change-speed box, the two all receives the identical hydraulic pressure from source of supply 98 certainly.Therefore, consider to have occurred any situation in vehicle startup process.Before starting, the pressure that is supplied to power-transfer clutch selector valve 104 is isolated valve 105 and discharges.Neither one power-transfer clutch engages, and therefore wheel is separated with change-speed box.In order to start to start, setpoint clutch selector valve 104 is to realize D Drive or reverse gear, and pressure source of supply 98 is set as suitable low value, then makes the state of disconnecting valve 105 change over this pressure is applied to relevant power-transfer clutch.Because the torque peak of power-transfer clutch always surpasses the output torque of change-speed box, so initial change-speed box will be forced to adopt its fastest ratio, this fastest ratio is determined by end stop buffer 106.No matter change-speed box change-over valve 100 is in what state, this all will occur, but any " the vexed sound " in fact producing in order to avoid, due to clutch moment of torque, change-speed box is urged to the terminal of its gear range, change-over valve 100 is also set as at first and orders about change-speed box and reach its fastest ratio.

Effectively the joint of power-transfer clutch is applied to driven wheel by moment of torsion, and vehicle starts to accelerate thus.In launch process, sometime, the state of change-speed box change-over valve 100 changes, thereby the hydraulic pressure applying trends towards ordering about piston 96 away from its energy disperser 106, to increase transmission ratio.The time selection of this variation is inessential, as long as there is this when effective clutch slip, changes, because at this moment, under any circumstance change-speed box all remains on its fastest ratio place by the moment of torsion being applied by effective power-transfer clutch 62 or 68.When vehicle accelerates, from the pressure of source of supply 98, increase gradually, and sometime effectively the slip of power-transfer clutch stop.After this, increasing continuously of hydraulic pressure can make piston 96 move away its end buffer 106, thereby transmission ratio can accelerate and increase along with vehicle.

In acceleration and brake process afterwards, because being less than the torque peak of effective power-transfer clutch for be applied to the load of effective power-transfer clutch by change-speed box, so do not expect that effective power-transfer clutch slides.

Effect has been to provide a kind of like this driving device, wherein can to the management of starting, control in very direct mode, and this driving device is showing the remarkable simplification that is better than known CVT aspect its hydraulic efficiency gear.

Modern power actuated vehicle typically realizes with electronics package the coordination strategy that change-speed box and driving engine are controlled.Here, consider CVT to control by this way.In this example, two amounts the most basic will controlling are exercised over variator reaction torque (being set by pressure source of supply 98) and engine output torque (being set by the torque demand that is supplied to engine controller).

Above-described embodiment only provides in the mode of example, and it is evident that for technical personnel, and the present invention can implement with multitude of different ways in practice.For example, the embodiment illustrating limits the stroke of roller, the thus transmitting ratio of limiting transmission with mechanical meeting device.Yet, known in the art be alternatively to use hydraulic efficiency gear, wherein the outlet on actuator 92 is formed in the side of its hydraulic actuating cylinder, thereby piston excessively advancing in either direction all will be closed this outlet, thereby and provides the function of terminal block.The device of same-type also can be used to realize the present invention.Similarly, although the embodiment illustrating adopts mechanical ball and slope apparatus that drawbar load is provided, this function also can utilize hydraulic efficiency gear to realize in other embodiments.Well-known, for example, to actuator 92 with act in one of them variator races to provide the hydraulic piston/hydraulic cylinder device of end load to supply identical pressure, can realize same function in an embodiment of the present invention.

Claims

1. a vehicle positive infinite variable driving device, comprise the rotation input that can be connected to rotating driver, can be connected to the rotation output of wheel, be connected between described rotation input and described rotation output so that the change-speed box of variable transmission ratio to be provided, and the launch device of being arranged to optionally connect/separated described rotation input and described rotation output, described change-speed box is constructed and is arranged to apply the moment of torsion needing, and described launch device is constructed and is arranged to provide the torque peak needing, described driving device is characterised in that, described driving device comprises control setup, described control setup is sent to described change-speed box to set the moment of torsion of described needs by identical control signal, and be sent to described launch device to set the torque peak of described launch device.

2. positive infinite variable driving device according to claim 1, wherein, the structure of described change-speed box and described launch device makes the torque peak of described launch device always surpass the output torque being applied by described change-speed box.

3. vehicle positive infinite variable driving device according to claim 1 and 2, wherein, described control signal is hydraulic pressure.

4. positive infinite variable driving device according to claim 1 and 2, wherein, described launch device comprises power-transfer clutch or drg.

5. positive infinite variable driving device according to claim 3, wherein, described hydraulic pressure is applied to the hydraulic actuator of described change-speed box, and has determined the power of the removable torque transfer member that is applied to described change-speed box.

6. positive infinite variable driving device according to claim 3, wherein, described change-speed box have on a pair of raceway running with by moment of torsion from a raceway be passed to another raceway removable roller, be attached to described roller power is applied to the hydraulic actuator of these rollers, and described hydraulic pressure is applied to described hydraulic actuator to determine described power.

7. positive infinite variable driving device according to claim 6, wherein, described change-speed box further comprises that of being attached in described raceway is to transfer a torque to the traction force-input device of this raceway/pass out from this raceway, and described traction force-input device is constructed and is arranged to the determined drawbar load of the moment of torsion by its transmission is applied to described raceway.

8. positive infinite variable driving device according to claim 7, wherein, described traction force-input device comprises first component and second component, and described first component and second component are installed into around a common axis rotation and are so shaped that parts cause that with respect to the rotation of another parts parts are with respect to the longitudinal travel of another parts.

9. a method of controlling vehicle positive infinite variable driving device, described positive infinite variable driving device comprises the rotation input that can be connected to rotating driver, can be connected to the rotation output of wheel, be connected between described rotation input and described rotation output so that the change-speed box of variable transmission ratio to be provided, and the launch device of being arranged to optionally connect/separated described rotation input and described rotation output, described method comprises: control described change-speed box so that the reaction torque of expectation to be provided, and as one man control the torque peak of described launch device with described exercised over variator reaction torque, so that the moment of torsion that is applied to described launch device by described change-speed box is always less than the described torque peak of described launch device.

10. method according to claim 9, the method comprises identical control signal is sent to described change-speed box and described launch device.

11. according to the method described in claim 9 or 10, comprise by little by little increasing the torque peak of exercised over variator reaction torque and described launch device and carry out starting of management vehicle, the described torque peak of described launch device always surpasses the moment of torsion that is applied to described launch device by described change-speed box, at least until the slip of described launch device stop, thereby until then, described driving device one keeps its fastest ratio straight through the moment of torsion that is passed to described driving device by described launch device.