Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H37/00—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00
  • F16H37/02—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings
  • F16H37/06—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts
  • F16H37/08—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts with differential gearing
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H37/00—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00
  • F16H37/02—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings
  • F16H37/06—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts
  • F16H37/08—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts with differential gearing
  • F16H37/0833—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts with differential gearing with arrangements for dividing torque between two or more intermediate shafts, i.e. with two or more internal power paths
  • F16H37/084—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts with differential gearing with arrangements for dividing torque between two or more intermediate shafts, i.e. with two or more internal power paths at least one power path being a continuously variable transmission, i.e. CVT
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H37/00—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00
  • F16H37/02—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings
  • F16H37/06—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts
  • F16H37/08—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts with differential gearing
  • F16H37/0833—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts with differential gearing with arrangements for dividing torque between two or more intermediate shafts, i.e. with two or more internal power paths
  • F16H37/084—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts with differential gearing with arrangements for dividing torque between two or more intermediate shafts, i.e. with two or more internal power paths at least one power path being a continuously variable transmission, i.e. CVT
  • F16H37/0846—CVT using endless flexible members
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H37/00—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00
  • F16H37/02—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings
  • F16H37/021—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings toothed gearing combined with continuous variable friction gearing
  • F16H2037/025—CVT's in which the ratio coverage is used more than once to produce the overall transmission ratio coverage, e.g. by shift to end of range, then change ratio in sub-transmission and shift CVT through range once again
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H37/00—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00
  • F16H37/02—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings
  • F16H37/06—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts
  • F16H37/08—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts with differential gearing
  • F16H37/0833—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts with differential gearing with arrangements for dividing torque between two or more intermediate shafts, i.e. with two or more internal power paths
  • F16H37/084—Combinations of mechanical gearings, not provided for in groups F16H1/00 - F16H35/00 comprising essentially only toothed or friction gearings with a plurality of driving or driven shafts; with arrangements for dividing torque between two or more intermediate shafts with differential gearing with arrangements for dividing torque between two or more intermediate shafts, i.e. with two or more internal power paths at least one power path being a continuously variable transmission, i.e. CVT
  • F16H2037/088—Power split variators with summing differentials, with the input of the CVT connected or connectable to the input shaft
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
  • F16H61/66—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing specially adapted for continuously variable gearings
  • F16H2061/6604—Special control features generally applicable to continuously variable gearings
  • F16H2061/6614—Control of ratio during dual or multiple pass shifting for enlarged ration coverage
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
  • F16H61/66—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing specially adapted for continuously variable gearings
  • F16H2061/6604—Special control features generally applicable to continuously variable gearings
  • F16H2061/6615—Imitating a stepped transmissions
  • F16H2061/6616—Imitating a stepped transmissions the shifting of the transmission being manually controlled
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
  • F16H61/66—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing specially adapted for continuously variable gearings
  • F16H61/662—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing specially adapted for continuously variable gearings with endless flexible members
  • F16H61/66254—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing specially adapted for continuously variable gearings with endless flexible members controlling of shifting being influenced by a signal derived from the engine and the main coupling
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
  • F16H61/66—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing specially adapted for continuously variable gearings
  • F16H61/662—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing specially adapted for continuously variable gearings with endless flexible members
  • F16H61/66272—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing specially adapted for continuously variable gearings with endless flexible members characterised by means for controlling the torque transmitting capability of the gearing

Definitions

• the invention relates to a method for regulating the translation of a power-split automatic transmission.
• the invention further relates to a power-split automatic transmission for performing the method according to the invention.
• CVT gearboxes Gearboxes with continuously variable transmission ratios
• CVT transmissions power is transmitted, for example, by means of a belt that rotates between two pairs of conical disks, the effective radius of each pair of conical disks being variable by changing the distance.
• Other continuously variable translations are based on rolling elements that run frictionally between suitable toroid surfaces or other principles.
• CVT transmissions with the largest possible spread are advantageous. Values of up to> 6 are currently achieved.
• Fig. 1 shows a basic structure of a vehicle drive train with a power split transmission.
• a drive motor of a vehicle for example an internal combustion engine 2 is connected via a starting clutch 4 to a drive shaft 6 of a power-split transmission 8, the output shaft of which is designated by 10.
• the power-split transmission 8 contains a variator 12 with continuously variable transmission ratio and at least one gear transmission 14 and at least two control clutches K1 and K2, with which the variator 12 can be coupled to the gear transmission 14 in different ways.
• Inputs of an electronic control or regulating device 16 are provided with an accelerator pedal sensor 18, a power actuator position sensor 20 of the internal combustion engine 2, an engine speed sensor 22, a sensor 24 for an input shaft of the variator 12, which can also be the drive shaft 6, and a sensor 26 Detecting the speed of the output shaft of the variator 12, a sensor 28 for detecting the speed of the drive shaft 10 and possibly other sensors connected.
• an accelerator pedal sensor 18 an accelerator pedal sensor 18, a power actuator position sensor 20 of the internal combustion engine 2, an engine speed sensor 22, a sensor 24 for an input shaft of the variator 12, which can also be the drive shaft 6, and a sensor 26 Detecting the speed of the output shaft of the variator 12, a sensor 28 for detecting the speed of the drive shaft 10 and possibly other sensors connected.
• a sensor 28 for
• output signals are generated in the electronic control or regulating device, with which a power actuator 30 of the internal combustion engine 2, an actuator for the starting clutch 4, the pressure dependent on the torque in pressure cylinders for the conical disk pairs of the variator 12, the pressures in adjusting cylinders of the conical disk pairs 12 for changing its translation and the control clutches K1 and K2 are controlled. Wheelsets or a clutch and / or a brake for reverse travel are not shown.
• FIG. 2 shows an example of a power-split transmission with a variator 12, one of whose pair of conical disks 30 is non-rotatably connected to the drive shaft 6 and can be coupled to a first gear 32 via a first control clutch K1.
• the other conical disk pair 34 of the variator 12 is connected in a rotationally fixed manner to an output shaft 36, which in turn is connected in a rotationally fixed manner to the sun gear 37 of a gear transmission 14 designed as a planetary gear.
• the output shaft 36 can also be coupled via a control clutch K2 to a second gear 38, which is in rotary engagement with the first gear 32 via an intermediate gear 40.
• the second gear 38 is rotatably connected to the planet carrier 42 of the planetary gear, the planet gears 44 mesh with the inner gear 46, which is rotatably connected to the output shaft 10.
• the entire power-split transmission then acts like a simple CVT transmission, the overall transmission of which is used twice according to FIG. 3.
• the abscissa shows the translation i var of the variator and the ordinate shows the translation i ges of the entire power-split transmission.
• the overall translation along the low branch decreases linearly with increasing translation of the variator until the changeover point U is reached, at which the translation i va r a small, predetermined Has value.
• the control clutches K1 and K2 are switched over, so that the planet carrier 42 now rotates with the transmission shaft 6 corresponding to the transmission ratio between the first gear 32, the intermediate gear 40 and the second gear 38, which is connected in a rotationally fixed manner to the input shaft 6 and the planetary gear 14 takes effect.
• the gear ratios are selected such that the total gear ratio i ges of the power-split transmission is independent of the switching state of the control clutches K1 and K2 at the changeover point U. If the spreading range of the variator 12 is now traversed again, the translation i tot changes along the high branch (high-speed range) shown in FIG. 3.
• the R-branch shows the gear ratios for the reverse driving range.
• FIG. 4 shows another example of a power-split transmission, in which, depending on the actuation position of the control clutches K1 and K2, the gear ratios according to FIG. 5 result.
• FIG. 6 and 7 show a further example of a power-split transmission, in which the variator transmits torque from the lower disk set according to FIG. 6 to the upper disk set while the control clutches K1 and K1 'and open control clutches K2 and K2' are open, while at open control clutches K1 and K1 'and with closed control clutches K2 and K2' transmits torque from top to bottom.
• the torque transmission direction is therefore reversed at the switchover point.
• the gear ratios according to FIG. 7 result.
• Fig. 8 shows the basic structure of a further power-split automatic transmission with a variator 12 and two planetary gears 14 and 14 '.
• the total transmission ratio i tot of the transmission according to FIG. 8 depending on the transmission ratio r of the variator 12 is shown in FIG. 9.
• a common method for determining the gear ratio is to implement a speed controller that sets a target engine speed by changing the gear ratio in such a way that this target engine speed is set.
• the target engine speed is determined by evaluating a characteristic curve depending on the actuation of an accelerator pedal. Due to the behavior of a CVT gearbox, a control loop is required in every case, be it as a transmission controller or as a speed controller.
• the invention has for its object to provide a method for regulating the translation of a power-split automatic transmission with a variator and at least one gear transmission, which enables a comfortable and the friction pairing in the variator not wear out switching.
• the invention is further based on the object of providing a power-split automatic transmission for carrying out the method according to the invention.
• the claim 33 characterizes the basic structure of a power-split automatic transmission for performing the method according to the invention.
• Claims 34 to 42 are directed to advantageous embodiments of power-split transmissions according to the invention.
• Claim 43 is directed to a cascade valve 44, which is advantageously used in a control circuit according to Claim 44.
• the invention can be used for all types of power-split transmissions with a variator, in particular a conical pulley belt transmission.
• the invention is particularly well suited for use on power split transmissions which are used in vehicles.
• FIG. 1 is a block diagram of a vehicle drive train with a power split CVT transmission
• Fig. 2 shows a section through an embodiment of a power split
• FIG. 3 shows a translation diagram of the CVT transmission according to FIG. 2,
• 11 is a translation diagram for explaining a switching strategy
• 13 is a flowchart for explaining an area switching; 14 shows a basic illustration of a further embodiment of a power-split CVT transmission,
• 29 shows a basic illustration of a further power-split transmission
• 30 shows a modification of the transmission according to FIG. 29,
• Fig. 34 shows a cascade valve in two different positions
• 35 shows a hydraulic circuit with cascade valves.
• FIG. 10 shows the basic structure of control and regulating modules, as they can be implemented in hardware and / or software in the electronic control or regulating device 16 according to FIG. 1.
• the individual ovals represent function blocks or modules.
• a ns o ii strategy module 50 determines a target speed ns o ii of the engine or the drive shaft 6 depending on the position of the accelerator pedal 18 and the vehicle speed. This setpoint speed nsoii is fed to an adjustment controller 52, a range strategy module 54 and a starting strategy module 56.
• the area strategy module 54, the adjustment controller 52, the starting strategy module 56 and a contact controller 58 are additionally supplied with the actual speed of the motor or the drive shaft 6. Not all connections are mandatory, for example taking into account the actual speed in the starting strategy module. Additional connections can also be provided.
• the contact pressure regulator 58 to which the torque delivered by the motor 2 is additionally supplied, regulates the contact pressure of the conical pulleys of the CVT transmission or the variator, which is dependent on the torque and, in addition, the speed of the drive shaft 6, in such a way that no undesired slippage between the conical pulleys and the belt means occurs.
• the area strategy module 54 determines the gear ratio range (low-branch or high-branch) of the power-split transmission depending on the desired target speed and the actual speed and transmits a corresponding signal to a changeover module 60 that controls the control clutches accordingly.
• a parameter of the pressure controller 58 and the switchover module 60 is fed to the inputs of the adjustment controller 52, so that the adjustment controller 52, depending on its input signals, regulates the forces acting on the adjustment cylinders of the conical disk pairs in such a way that the actual speed approximates the target speed ,
• the starting strategy module 56 controls or regulates the actuation of the starting clutch 4 (FIG. 2) when starting depending on the target speed or the speeds.
• the ns o ii strategy module 50 determines the current power requirement in a manner known per se from, for example, the actuation of the accelerator pedal 18 and the current vehicle speed. An acceleration request made by the driver via the pedal is converted into a target speed such that the power calculated from the target speed and the engine torque corresponds to the power requirement. At the same time, the motor is operated in a manner known per se at a speed that is as fuel-efficient as possible. Such strategies and their advantages are known from conventional CVT transmissions. An equivalent strategy is that a target gear ratio is derived directly from the target speed.
• the adjustment controller 52 is responsible for adjusting the speed of the drive shaft 6, which also forms the transmission input shaft, to the desired speed by the forces on the disk sets and thus the translation of the variator and, depending on the activated translation range, so that the translation of the overall transmission is changed.
• the adjustment can be carried out by means of a subordinate gradient controller, which regulates a speed change rate.
• the adjustment controller 52 also contains corresponding differentiators.
• the adjustment controller 52 is advantageously supplemented by precontrols which support directly on the controller output. Such precontrols can be used, for example, to inevitably generate the necessary forces directly from the support profile. In order to take into account the non-constant reaction of a real variator to a change in force, further “decoupling factors" can be used. This allows for the fact that the variator is more or less sensitive depending on the translation.
• a first solution to this problem consists in the fact that at least one controller parameter of the adjustment controller 52 changes its sign when switching between the two transmission ranges.
• the respective effective sign is communicated to the adjustment controller 52 by the switch module 60.
• the controller parameter changed in sign can be a relevant parameter processed within the controller, which changes the output signal of the controller.
• a controller parameter possibly the output signal itself, is changed when switching over such that the sign of the output signal changes when switching over.
• a further development of the aforementioned solution consists in that not only is the sign of the output signal of the adjustment controller 52 changed depending on the translation range, but the output signal is additionally changed in accordance with the current value of dig es / divar, for example multiplied by this gradient.
• the gradient or the slope of the branches of the transmission curves indicates how strongly and in which direction the variator acts on the overall transmission. If a predetermined change in the overall ratio is desired, it is necessary to adjust the variator only slightly (B) or particularly strongly (C).
• the gradient (or its reciprocal) gives a measure for a factor by which the output of the adjustment controller 52 is expediently multiplied.
• the adjustment controller 52 is a PID controller by multiplying the P component of the controller by the current value of di ges / divar.
• the problem of operating two different adjustment directions with a single adjustment controller can be solved by changing an input signal of the adjustment controller corresponding to the deviation between the target speed and the actual speed according to the current value of di ges / divar, for example is multiplied by it.
• FIG. 12 shows the structure of an adjustment controller 52 (FIG. 10) as it can be used for the aforementioned problem solutions.
• a target speed change dn / dt S ⁇ ⁇ is fed to a control element 62, the other input of which is an actual speed change dn / dt
• the output signal corresponding to the difference between the input signals of the control element 62 is fed to a switching element 66, to which a switch module 60 feeds a signal which, depending on the activated area, influences the output signal of the control element 62, for example reversing the polarity.
• the output signal of the switching element 60 is fed to a proportional element 68 and an integral element 70, the output signals of which are in turn processed additively in the control element 72 together with pilot control signals, for example with respect to torque, speed, variator ratio, temporal change in the desired speed.
• the output signal of the control element 72 determines the adjusting force supplied to the variator.
• the influencing element 66 can advantageously also be within a translation branch (see FIG. 3 high branch or, for example, FIG. 5 low branch), the adaptation of which to a special ratio between the overall translation and the variator translation can be used.
• the high branch can be adapted so that a linear characteristic is created.
• the integrating element 70 can be acted upon by performing an adjustment pulse (not shown) when the range is switched.
• the output signal of the integrating element 70 is influenced once, which causes a step change of a predetermined height in the adjusting force effective on the variator.
• This adjustment impulse is always directed in such a way that it causes the variator to be moved away from the variator switchover ratio, ie it acts like a "reflection of the displacement of the moving disk during the switchover".
• the amount of the adjustment pulse depends on how quickly the changeover ratio is adjusted, ie how large dn / dt S ⁇ ⁇ is.
• the left part represents a flowchart of a switchover as it takes place in the switchover module 60 (FIG. 10).
• the right part of FIG. 13 represents a switchover with respect to the part relating to the adjustment controller 52.
• step S1 the area strategy module 54 (FIG. 10) checks whether a change of area is necessary and possible. If this is the case, a control signal for opening a first control clutch is generated in step S2. As will be explained further below, in the case of a downshift or an upshift, it is expedient to delay the closing process of a second control clutch somewhat if a performance criterion is not met. It is therefore checked in step S3 whether the performance criterion is met. If this is not the case, the first clutch remains open. If this is the case, the other clutch is closed in step S4. In step S5, the opening of the first clutch and the closing of the second clutch are carried out completely and the switchover is ended.
• step S6 The adjustment controller 52 (FIG. 13) can be used in both transmission ranges (branched and unbranched operation) if its input gear continuously detects the current section, for example by means of the signal di- g e s / di Va r- In step S6, the normal is performed, with reference to FIG. 12 described adjustment regulation or Variatorregelung. If it is determined in step S7 that a range change is taking place, then in step S8 a pulse is applied to the integrating element 70, which leads to the step-wise change of the adjusting force on the transmission described.
• the gear ratio of the variator i var When driving through the overall gear ratio i tot , the gear ratio of the variator i var must be adjusted close to the switchover point U and then regulated away from the switchover point U. If this reversal is not carried out exactly, the vehicle will jerk uncomfortably. This jerk also means increasing wear on the belt means of the variator or the friction pairings contained in it.
• a first solution to the aforementioned problem is that the controller input signals are reduced during the changeover of the control clutches K1 and K2, for example by multiplying them by a factor which is ⁇ 1 during the changeover or even switches digitally to zero. In this way, the effective soli-actual deviation communicated to the adjustment controller 52 is reduced during the switchover. It is thereby achieved that the potentially disturbed signals, which influence the adjusting controller 52 during the switching of the control clutches K1 and K2, are harmless.
• a further solution to the aforementioned problem which can be taken as an alternative or in addition to the aforementioned measures, consists in changing existing I components in the adjustment controller 52 when switching between the translation ranges, in particular reducing or particularly advantageously jumping be properly set to zero.
• a further embodiment of the method for solving the above-mentioned problem 2 consists in allowing the part of the I component that caused the switchover point U to move at a speed divar / dt to continue to exist. In the ideal case of a perfect feedforward control, this is the entire I component, which can then continue to exist as an I component after multiplication in accordance with the solution to problem 1 and can make a contribution to the readjustment of the variator.
• Fig. 14 shows a further example of a power-split transmission with a variator 12, a first planetary gear 14 ⁇ , a second planetary gear 14 2 and a downstream transmission stage FD, the torsionally soft connection with the other elements of the vehicle is symbolized with 62.
• a starting clutch (not shown) is advantageously provided between the engine 2 and the transmission.
• a clutch for reverse travel is not shown.
• the wiring of the planetary gear 14 ⁇ and 14 2 z. B. be the following:
• the sun gear of 14 ⁇ is rigidly connected to the output shaft of the variator 12; the planet carrier of 14-j is rigidly connected to the ring gear of 14 2 , which is rigidly connected to the output of the control clutch K2; the ring gear of 14- ⁇ is rigidly connected to the planet carrier of 14 2 , which is rigidly connected to the input of the transmission stage FD; the sun gear of 14 2 is rigidly connected to the control clutch K1.
• the division strategy comprises the following steps:
• the overall gear ratio and the variator gear ratio are different depending on the gear ratio range.
• An obvious calculation of the overall gear ratio would be to measure the transmission input and output speed and divide them by each other.
• the variator translation could then be calculated from the above-mentioned translation formulas.
• the former variant has the disadvantage that the gear ratio of the variator cannot be determined if one of the clutches or brakes slips. With that special control control algorithms are not feasible without additional sensors, such as a control in the neutral state explained below.
• Vibration decoupling is possible in the same way as conventional CVT transmissions.
• the translation at the changeover point is fixed by the structure of the gearbox.
• the area strategy can be represented in the form of a state machine, as will be explained below with reference to FIG. 16.
• the low state shown in the left circle causes the opening of a power path parallel to the variator 12 (in the example of FIG. 12 opening K2) and the closing of another power path (closing the clutch K1).
• the high state shown in the right circle closes the power path parallel to the variator and opens another power path.
• the neutral state shown in the middle circle opens both the power path parallel to the variator and a further power path, so that the transmission has no frictional connection.
• the switchover from low range 1 to high range 2 is advantageously carried out if the following conditions exist:
• Switching not just at the exact switchover point U, but just before it, increases comfort.
• the changeover is thus carried out with a small step-up in gear ratio and speed, which can be conveniently designed by suitable actuation of the clutches.
• the switchover before the actual switchover point is achieved in that the term c is present in the aforementioned conditions. With the term bx dn ⁇ st , the switchover also takes place somewhat earlier in order to take account of dead times in the actuators.
• the state zero is used at standstill or z. B. for braking with ABS intervention or more generally with blocking wheels to facilitate the adjustment of the variator for starting translation.
• the condition for activating the neutral quick adjustment according to UD means that there is a blockage braking that requires a translation adjustment beyond the range change that was not implemented sufficiently quickly.
• 17a shows the overall gear ratio i g ⁇ S of the power- split transmission depending on the gear ratio i va r of the variator.
• the low curve corresponds to high gear ratios.
• the high range corresponds to lower translations.
• the overall transmission ratio is independent of whether the low range or the high range is activated.
• the low range is switched to the high range before the switchover point.
• the high range is switched to the low range before the changeover point.
• the changeover point is passed over in the low range, then switched over to the high range, in that the changeover point U is then again passed over.
• the switchover point U is passed in the high range and then switched to the low range.
• the hatched area at d) and e) each represents a performance criterion that must be met in order for the gear to be switched over or the initially open clutch to be closed. The criterion means that acceleration power is released in pull circuits and deceleration power in push circuits. In d) and e) two trajectories of possible comfortable switching are drawn.
• Fig. 19 shows a traction upshift as shown in FIG. Y When pulling downshift at the time i var 18. However, due to the application of y in Fig. 17 shown strategy less than iv a r in the case of Fig. 18 at the time. Vehicle acceleration and engine speed show significantly lower vibrations, which indicates improved comfort.
• the cause of the aforementioned problems are internal gear masses, in particular the mass of the variator disc pair on the output side, which require a large acceleration power when adjusting the gear ratio. This power is lost to the tractive force and changes, for example at the switchover point U, cause a jerk.
• Constructive remedial measures consist in a favorable choice of the translations of the planetary gears with otherwise the same gear properties. It is advantageous if it is small and i 2 is large. It is also advantageous to work with countershaft instead of countershaft, ie countershaft transmissions in front of the pair of disks on the input side. The pair of disks on the output side should be coaxial with the sun gear of the planetary gear. drive 14 ⁇ be arranged. It is also advantageous to have a low rotating mass in the
• the driving strategy must dynamically reduce the speed gradients based on traction.
• the two translation ranges are implemented as two states of an automaton (FIG. 16).
• the switching process is part of the respective state of the area and is carried out by counting up or down a variable u.
• the decision to carry out a switchover is made on the basis of a speed criterion.
• a switchover speed is calculated. If the current speed (plus D components) and the target speed (plus D components) are on the other side of this changeover speed, the status is changed and the changeover is triggered.
• the switchover variable u (which can assume values between 0 (unbranched operation) and 1000 (branched operation), for example) specifies the area in which driving is to take place and represents an interface variable for other modules.
• the switchover is performed by counting up or down of the variable u in the state machine.
• the variable u is continuously taken into account in several places:
• the respective clutch torques are calculated from the engine torque with the aid of transmission-dependent kme factors.
• the first control clutch K1 (FIG. 14) acting as a brake must be closed in the UD with a multiple of the engine torque, but at the switchover point U only with the engine torque itself.
• the engine torque is a dynamic engine torque that takes speed changes into account.
• the dynamics of the switchover are achieved by a dependency of the value of the variable u, ie the switchover is tuned on the basis of a characteristic curve dependent on u for each clutch and on the basis of the logic for up / down counting of u. Opening a clutch is quicker than closing.
• the motor intervention is taken into account in the state machine.
• the jump in inertia is proportional to the speed gradient.
• a translation-dependent function is added in the branched area and, in the unbranched area, a temporally limited (e.g. on two half-waves) active bucking damper can advantageously be used after a switchover.
• Another way of solving the problem of the inertia of the power-split transmission is to consciously change the speed gradient in branched operation in such a way that the acceleration power for internal gear masses changes less or in branched operation to change the speed gradient in such a way that the acceleration power at the output of the gearbox changes monotonously or continuously (i.e. increases linearly with a train downshift).
• a train downshift this leads, for example, to a non-linear, but thereby jerk-minimized increase in the engine speed; before switching slowly, then faster.
• the branched operation In the area of the switchover or in the vicinity thereof, it can be quite relevant for damage to the belt, for example a metal chain, whether driving in the low translation range or in the high translation range (unbranched or branched operation).
• the branched operation In a power split transmission with a transmission behavior according to FIG. 20, the branched operation generally has a higher chain damage than the unbranched operation.
• the approached operating point in the wear-resistant area must provide the same traction or wheel power as the originally selected area with high chain damage.
• the new operating point can be started by the engine management system.
• the chain damage can also be taken into account in gearboxes with tiptronic switching (manual switching of gear ratios), so that areas with power split close to the area switchover are avoided.
• the present strategy is advantageous for all types of variators with friction pairings.
• the target gear ratio or the target speed is in the range of the range switchover U, small changes in the target speed or target gear ratio can result in oscillating circuits, which should also be avoided under chain damage aspects.
• a first solution to the above problem lies in the fact that a switch back to a previous operating range is only carried out when the desired target gear ratio is clearly removed from the switchover point U, i. H. a defined hysteresis area is left. This is shown in Fig. 21.
• the hysteresis range can be specified as a differential ratio or as a differential speed.
• the target ratio is limited to the ratio of the variator at its stop. Depending on the operating point, higher speeds can then be set; a change of division is avoided.
• the target gear ratio should be approached in a suitable manner, for example by linearly reducing the gear ratio difference ⁇ i ges .
• An alternative or additional solution to the problem can be that an area change only takes place after a predetermined period of time has elapsed since the last area change.
• a still different or additional solution can be that a switch back to the old operating range only takes place if the driver expresses the wish by means of a corresponding signal, for example the accelerator pedal has been actuated since the last range change, the service brake has been activated since the last range change, operated the gear selector lever, etc.
• the build-up as well as the dismantling of the overpressure can be realized by a wide variety of functions, such as a jump, a ramp, a PT1 function etc.
• Fig. 22 illustrates the situation.
• the abscissa represents the time, which is labeled MK
• the vehicle drive train reacts to sudden torque changes with a jerk, i.e. H. even with an overshoot of the moment.
• the transmission range is switched over by opening a clutch or brake K1 and closing a clutch or brake K2.
• the torque scale MK is shown relatively, ie 100% denotes the respective torque that would be required under stationary conditions so that the control clutch K1 or K2 does not begin to slip.
• the moment marked M var on the variator changes its sign when switching over and clearly overshoots.
• the negative peak value is approximately 200% of the moment that existed before the switchover. Such high moments can lead to premature failure of load-critical components such as shafts, gears, the chain, etc.
• control clutches K1 and K2 are closed so strongly that sufficient security against slipping of the clutch is achieved even in dynamic situations.
• a changeover of the clutches is advantageous according to the invention, in which for a short period of time (marked with * *) after the changeover, the clutch (in the example shown K2) only slightly beyond the required amount (for example 120 to 130 %) is closed.
• the negative peak Zen torque can be significantly reduced, in the example shown to about 130% of
• a high target speed ns o ii is started up, typically 5,800 rpm for gasoline engines, in order to achieve maximum engine power and thus maximum acceleration.
• This is shown in Fig. 24.
• the two curves represent a speed curve and a speed curve over time.
• the actual speed n is adjusted to the target speed ns o ii by the variator adjustment control while the vehicle is accelerating.
• the range is switched at 5800 rpm and the greatest possible torque.
• the target speed before the range changeover is limited to an advantageously speed-dependent value of, for example, between 5000 and 5400 rpm.
• This limitation is lifted after the switchover, so that the initially limited speed ns o approaches the value nsoii.
• the changeover therefore takes place at a speed of only 5400 rpm in the example shown.
• the loss of engine power at low speeds is accepted.
• the lower engine speed is not only associated with less chain wear, but also with better noise comfort (Fig. 25).
• an engine intervention takes place preferably before and after the switchover.
• the power required, for example, by a hydraulic pump to generate the pressing and adjusting forces of the variator changes in general when switching over.
• the torque acting on the variator jumps when switching.
• the jump in torque is accompanied by a jump in the full contact pressure and thus the pump torque.
• losses (when the torque increases) can increase, which additionally costs engine power.
• Motor intervention which is possible in a simple manner on motors with a power actuator actuated by an actuator, can be used to slowly reduce the engine power shortly before the switchover, in order then to jump suddenly to the original level during the switchover. Additionally or alternatively, the engine power can be increased suddenly in order to slowly return to the original level after the changeover.
• the engine power changes can be coupled with the current gear ratio.
• the level of the maximum engine intervention depends on the power jump effective on the engine, which can generally be applied approximately in proportion to the current engine torque.
• the proportionality constant can generally be predetermined and is generally a maximum of up to 5%.
• Another reason for an electronic motor intervention is the combination of the jump in dynamic moments of the variator. Because the gear ratio of the variator changes in opposite directions before and after the changeover, moments that the vehicle acceleration is released due to acceleration changes in the output shaft of the variator, which are associated with the gear ratio range changeover. change. For example, if the output shaft of the variator was accelerated before the switchover, while it is braked after the switchover, the released moments cause the vehicle to accelerate.
• the motor intervention that occurs when switching over takes this jump of dynamic moments into account by having an amount in the example described that is smaller in the new gear ratio range than in the old one.
• the component is proportional to the amount of the adjustment speed of the variator, the proportionality constant resulting from the rotating mass at the output of the variator.
• the dynamic moment described has an accelerating effect on the vehicle, regardless of the direction in which the switchover point is passed. It goes without saying that there are also transmission designs in which the dynamic change in torque associated with the changeover has a braking effect on the vehicle, so that the engine power must be increased for compensation.
• curve I represents the time course of the translation of the variator of a power-split transmission, U being the changeover point.
• the curve Ha denotes the vehicle acceleration before the switchover point and curve 11b indicates the vehicle acceleration after the switchover point.
• Curve III shows the engine power. A process is shown in which acceleration takes place with medium engine power.
• a characteristic of the transmission control of power-split transmissions in the area of the switchover point is that the translation is first quickly moved to an end position of the variator and then away from it.
• the adjustment control In order to make the switch between the power-split and the unbranched area as little as possible noticeable for the driver, the adjustment control must contain a stable and precise adjustment of the translation in addition to high dynamics. The two requirements are usually contradicting each other.
• the pulse is advantageously applied in the I component of the adjustment controller, the pulse being able to be triggered by the switch module 60 (FIG. 10).
• the pulse or the precontrol achieved thereby is increased when a large target gradient is required. It is further advantageous if the applied pulse or the applied pilot control is greater than the desired adjustment gradient. It is also advantageous if the pulse height or the precontrol is from the value of the I component of the adjustment controller before the switchover. Furthermore, it is advantageous to increase the pulse or the pilot control when the input torque acting on the variator increases.
• the pulse can be proportional to the input torque, for example.
• the design criteria of a variator that is used in a power-split transmission differ from that of a CVT transmission that is used alone in that the variator in a power-split transmission can be operated with very high torques both in the train and in the overrun ,
• the shift between these gears can be made crisper by not actuating the clutches only at the changeover point, but rather directly outside the changeover point by actuating the clutches jumping from one branch to the other branch, so that a shock is deliberately introduced into the transmission.
• the switching of the control clutches can be connected in various ways with the adjustment of the gear ratio of the variator, so that the shift shock receives a preselectable amplitude.
• Power-split gearboxes that contain a variator make it possible to decouple the variator from the output by opening certain control clutches. In this state, a standstill adjustment can be carried out when the output is at a standstill because the conical disk pairs continue to rotate. This is for example at 2 possible when the control clutches K1 and K2 are open.
• Power-split transmissions with a variator generally require a lot of installation space. 29 shows an advantageous embodiment of a power-split transmission.
• a drive shaft 80 driven by an internal combustion engine can be brought into rotary engagement with the input shaft 82 of a variator 12 via a starting clutch AK.
• the output shaft 84 of the variator 12 meshes with an input sun gear 86 of a planetary gear 88 designed as a summing gear.
• the input sun gear 86 is in rotary engagement with a first ring gear 92 via the planet gears of a first planet carrier 90, which simultaneously forms a second planet carrier 92a for associated planet gears.
• the planet gears of the second planet carrier 92a mesh on the one hand with a second sun gear 94 and on the other hand with a second ring gear 96, which is non-rotatably or rigidly connected to the first planet carrier 90.
• the first ring gear is rotatably connected to an output shaft 98, which in the example shown is connected to the rear wheels of a vehicle via a differential and is connected to the front wheels of a vehicle via further shafts and a differential. It goes without saying that the four-wheel drive is optimal.
• the drive shaft 80 is sufficient. through the starting clutch AK, the variator 12 and the first sun gear and is connected to the drive disk of a second control clutch K2, which is received in the first ring gear 92 and the second planet carrier 92a and whose output side is connected to the first planet carrier 90.
• the rotation of the second sun gear 94 can be fixed via a first control clutch K1.
• the rotation of the first planet carrier 90 and of the second ring gear 96 rigidly connected to it can be fixed by means of a further clutch KR, which forms the clutch for reverse travel.
• a compact design is achieved by arranging the second control clutch K2 within the planetary gear 88. It goes without saying that numerous modifications of the transmission are possible.
• the drive shaft 80 can be directly the input shaft of the variator, gear ratios can be arranged differently, etc.
• FIG. 30 shows a modification of the transmission according to FIG. 29, in which the starting clutch AK is missing and the drive shaft 80 permanently meshes with the input shaft 82. Clutches K1 and KR are used together for starting. In this way, starting clutch AK according to FIG. 29 can be saved.
• FIG. 31 shows four types of power-split transmissions, each with two coupled planetary transmissions with unique solutions for the respective speeds, such that the transmission range of the variator, not shown in FIG. 31, is similar to that of the transmissions according to FIG. 29 and 30 can be used twice by operating the gearbox in unbranched and power-split operation by appropriately controlling clutches which are also not shown in FIG. 31.
• Ani describes the drive shaft for unbranched and power-split operation; Denoted at 2 is the drive shaft for power-split operation, which is achieved by engaging the clutch designated K in each case. Ab denotes the output.
• Bi and B 2 are the brakes for reverse and forward travel.
• the two planetary gears are each indicated by circles (Wolf's symbol) and their standard translations and i 2 symbolized therein.
• the four types differ by the coupling of the drive shafts to the planetary gear, the coupling of the output shaft. the planetary gears and the arrangement of the brakes, which each result directly from the figures.
• the coupled planetary gears shown can be connected together with the variators (not shown) to form power-split gears, which are preferably controlled or regulated according to the above-described methods. Protection is claimed for the structure of the gear types shown, regardless of their control.
• the task of pressing-erstell / creation systems is to generate the pressure forces of the conical pulley pairs required for the variator so that the belt does not slip and, if desired, a gear ratio adjustment.
• the pressure requirement is dependent on the torque transmitted.
• adjusters for translation changes are also possible.
• Pressure chambers of the two sets of discs are hydraulically connected.
• the hydraulic pressure is dependent on a torque sensor that controls a corresponding valve.
• the adjustment forces are generated in an adjustment unit with a corresponding adjustment chamber, the pressurization of which takes place via one or two controllable valves.
• a smaller pump can be used with this arrangement.
• the disadvantage is that the dependency of the pressure requirement on the translation can only be represented with relatively great effort.
• the torque sensor is replaced by a controllable proportional valve.
• the dependency of the contact pressure on the moment and the translation is stored in a control.
• the aforementioned disadvantages can be avoided.
• a pair of conical disks 30 is shown with a fixed disk 30a and an adjusting disk 30b.
• the adjusting disk is pressurized by a pressure chamber 100 and an adjusting chamber 102.
• the pressure in the pressure chamber 100 of the pair of conical disks shown and the pressure in the pressure chamber 100 of the pair of conical disks not shown is controlled by means of a valve 104, preferably a proportional valve.
• the pressure in the pressure chamber 102 is controlled by means of a valve 106 and the pressure in the pressure chamber, not shown, of the other disk pair is controlled by a valve 108.
• the valves are pressurized by a pump 110.
• a control device 112 is used to control the valves and the pump 110, the inputs of which are suitably Neten sensors and / or other control devices are connected and the outputs thereof control the valves and, if necessary, the pump 110.
• the structure and function of the units described are known per se and are therefore not explained. It is understood that the control device 112 can be connected to a bus system.
• the pressure forces of the disk sets are calculated in a manner known per se. This can be done either by determining the target forces stored in a memory, the respective target force being determined depending on the transmitted torque, the instantaneous gear ratio and the desired adjustment, or also in the form of the actual forces, which are detected by sensors, or by a combination both options.
• a third step the pressures pm and pv required in the pressure chamber and the adjustment chamber of the pair of disks to be applied with the greater force F are determined in such a way that there is approximately equal pressure. In this step it is calculated z.
• a fourth step the contact pressure pv of the other disk set pair to be applied with the small force is then calculated. In this step it is calculated z.
• B. pv (F-pm * Am) Av, where pm is the already known contact pressure and Av and Am are now the surfaces of the contact and adjustment space on the set of discs on which the smaller force F is required.
• the situation may arise that the variator can be operated at very low pressures because only very small moments are transmitted by it. Nevertheless, high hydraulic pressure may be required for other components of the transmission, which are not shown in FIG. 32, for example for a starting clutch or on other shifting elements.
• Another application of deliberately increased pressures can be motivated by, for example, spray oiling or oil cooling to be improved. It may also be advantageous to maintain a slight minimum pressure in order to e.g. B. to prevent "draining" of hydraulic lines or chambers, which improves the reproducibility of the control of these chambers or also maintains lubrication of moving parts. In the case of a cold transmission, it would even be desirable to temporarily reduce the efficiency by increasing the pressure, so that the gearbox and possibly also the internal combustion engine reach a favorable working temperature more quickly.
• the minimum pressure logic is implemented in that, after the aforementioned third step, the calculated contact pressure is modified by increasing it (at the same time the adjusting pressure required to maintain the greater contact pressure is correspondingly reduced) until either the contact pressure reaches the required minimum pressure or until In the fourth step, the adjustment pressure for the other set of disks reaches the minimum pressure.
• overpressure can be accepted if an adjustment pressure has to be reduced to zero.
• the aforementioned methods can be implemented using software alone, so that they are extremely inexpensive.
• a cascade valve as will be described below with reference to FIGS. 33 and 34, is particularly suitable for carrying out the above-described method.
• a cascade valve has a valve member 120 which works in a cylindrical housing 122, which is only drawn in its inner contour and which has a cylinder bore 126 stepped at 124.
• the cylinder bore is closed on the left side, so that on the left side of a collar 128 of the valve member 120 which is guided in the section of the cylinder bore 126 with an enlarged diameter, a chamber 130 is delimited which is supplied with pilot pressure.
• the valve member is formed with a smaller diameter, so that a first annular space 134 is formed which, in the position of the valve member according to FIG. 32, has a first outlet 136 on the left side, which can be connected to a consumer.
• the annular space 134 has a first inlet 138 which can be connected to an oil pump.
• valve member On the right side of collar 132, the valve member has a shaft with a reduced diameter and then another collar 140, so that a second annular space 142 is formed.
• the second annular space 142 is connected to a second inlet 144, also connected to a hydraulic pump, and an outlet 146 is arranged such that it flows from the second annular space by means of a control edge formed at the right-hand end of the collar 132 142 is separated.
• a return is also arranged in the area of the federal government 128.
• the position according to FIG. 33 corresponds to a pressure limiter position of the cascade valve; the entire hydraulic fluid flow coming from the hydraulic pump is through through the first annular space 134 to the outlet 136, the pressure acting in the first annular space 134 counteracting the pilot pressure in the chamber 130 because of the stepped cylinder bore 126 and thus the unequal diameter of the collars 128 and 132. If the pressure in the first annular space 134 becomes too high, the valve member 120 moves to the left, as a result of which the inlet into the first annular space 134 is increasingly closed by the control edge of the collar 132 and the second outlet 146 is increasingly opened. The volume flow coming from the pump is thus biased in the cascade valve by the pressure limiting function and a pressure determined by the pilot pressure for the consumer downstream of the first outlet 136 is set.
• valve member 120 moves increasingly to the left and assumes the pressure reduction position according to FIG. 34, in which the first annular space 134 is separated from the first inlet by the left-hand control edge of the collar 132 is and is increasingly connected to a return 148 via the right-hand control edge of the federal government 124.
• the right or second annular space 142 connects the second inlet 144 to the second outlet 146.
• FIG. 35 A hydraulic diagram for controlling the pressure chambers 160 of two conical disk pairs of a variator and the adjustment chambers 162 and 164 of each conical disk pair is shown.
• a hydraulic pump 166 generates a volume flow that is limited in a volume flow limiting valve VQP and then flows through a pilot pressure valve (not designated) and is fed to the inlets of a first cascade valve KV1.
• the first outlet of the cascade valve KV 1 is connected to the pressure chambers 160.
• the second outlet leads to the inlets of a second cascade valve KV2, the first outlet of which is connected to the adjustment chamber 162 and the second outlet of which is connected to the inlet of a third cascade valve KV3.
• the first outlet of the third cascade valve KV3 is connected to the adjustment chamber 164 and the second outlet advantageously leads to at least one unit of the variator operated in flow mode, for example an opening for cooling the conical disks and / or for feeding a centrifugal oil hood with hydraulic fluid etc.
• the pilot pressure of the cascade valves are controlled via valves which are shown on the left-hand side and are electronically controlled by a control unit (not shown), via which valves are also controlled which control the individual clutches K1, K2, KA and KR of a transmission, as shown in FIG. 35.
• the pressure in the pressure chambers 160 is considered to be the most important, so that these chambers are connected to the cascade valve KV1.
• Another advantage of the cascade valves described is that, in their pressure-limiting position, they return hydraulic medium flowing back from the consumer into the control system, so that the hydraulic medium is available to other consumers. This has a positive influence on the volume flow balance of the control and allows the use of smaller pumps.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Control Of Transmission Device (AREA)
• Transmission Devices (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=27674581

Family Applications (1)

Country Status (9)

Families Citing this family (93)

Family Cites Families (49)

• 2003
  • 2003-01-27 KR KR10-2004-7012261A patent/KR20040096556A/ko not_active Application Discontinuation
  • 2003-01-27 EP EP03704248A patent/EP1474623A2/de not_active Withdrawn
  • 2003-01-27 AU AU2003206639A patent/AU2003206639A1/en not_active Abandoned
  • 2003-01-27 CN CN2008101767157A patent/CN101398068B/zh not_active Expired - Fee Related
  • 2003-01-27 WO PCT/DE2003/000203 patent/WO2003067127A2/de active Application Filing
  • 2003-01-27 CN CNB038035839A patent/CN100432494C/zh not_active Expired - Fee Related
  • 2003-01-27 US US10/503,170 patent/US7493203B2/en not_active Expired - Fee Related
  • 2003-01-27 DE DE10302992A patent/DE10302992A1/de not_active Withdrawn
  • 2003-01-27 JP JP2003566445A patent/JP2005517140A/ja active Pending
  • 2003-02-05 NL NL1022590A patent/NL1022590C2/nl not_active IP Right Cessation
• 2005
  • 2005-10-04 NL NL1030106A patent/NL1030106C2/nl not_active IP Right Cessation
• 2006
  • 2006-04-21 NL NL1031664A patent/NL1031664C2/nl not_active IP Right Cessation
• 2009
  • 2009-04-24 JP JP2009105968A patent/JP5023383B2/ja not_active Expired - Fee Related

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events