DE4417335A1 - Continuously variable hydrostatic/mechanical split-torque transmission - Google Patents

Abstract

Published without abstract.

Description

The invention relates to a continuously variable transmission, preferably a hydrostatic power split transmission and whose control and regulating device according to the preamble of Claim 1 and other independent claims. The gear allows different driving strategies or driving programs that are user-friendly adjustable or available. Furthermore is a hydrostatic bypass at several transmission points switchable and maximum possible braking effect via the stepless hydrostatic converter can be used and easily controlled. In addition, braking energy in a further embodiment can be recovered via the hydrostatic converter. For Switching optimization of the range switches is a targeted one Adjustment correction of the stepless converter provided.

Similar sub-facilities are already known. You require however greater expenditure in terms of cost, weight and installation space.

The object of the invention is to overcome these disadvantages, in particular stepless gears, especially hydrostatical-mechanical power-split transmissions to eliminate. Furthermore should also take advantage of the continuously variable transmission Improvement of the facilities known from EP-A-0280 757 be more exploitable.

This object is achieved by the in the Main claims listed features solved. Further advantageous embodiments of the invention are shown in the Subclaims and the description.

The invention is based on exemplary embodiments with reference to Drawings explained. Show it

Fig. 1 Another embodiment of the control device for a transmission with several shift ranges.

Fig. 2 transmission structure with traction booster.

Fig. 3 system representation of the summing / branching gear.

Fig. 4 to 4c transmission structure with hydrostatic braking device (hydrostatic retarder).

Fig. 4d hydrostatic power split transmission according to the inline design, which can be carried out with the devices according to the invention.

Fig. 4e Noiseless hydrostat storage.

Fig. 5 gear with device for braking energy recovery.

Fig. 6a u. 6b Selector lever with preselection for program preselection and / or stepless translation setting option.

Fig. 6c alternative of the actuator such as 6a and 6b, but on the steering wheel.

Fig. U 6d. 6e Diagrams which show the course of the setting for determining a constant speed or constant ratio depending on the setting time "t" or the setting path "s".

Fig. 6f consumption characteristic.

Fig. 6g diagram of the acceleration characteristic.

Fig. 6h diagram braking components.

Fig. 6i, 6k, 6m diagram of drive control.

Fig. 6l kick-down characteristic.

Fig. 7 u. 7a adjustment, speed, torque, pressure curve during a switching sequence.

Fig. 8 circuit diagram.

As already known from European patent application 0 280 757, a driving program preselection - overdrive area or performance-oriented program - is possible via the accelerator pedal or actuating devices in the area of the accelerator pedal for foot actuation. Similarly to the above-mentioned known control and regulating device, the invention uses the speed of movement of the accelerator pedal 6 as an influencing variable or control impulse for calling up one or more of the programmed driving programs. A short, quick tap on the accelerator gives the control device 5 the command to call up the corresponding performance-oriented program, whereby the engine is raised in its speed, for. B. to prepare for an overtaking. One or more programs or characteristic curves (A1; A2; A3; A4 - Fig. 6f) can be provided in order to meet the different driver types or the different driver demands.

The invention further provides for a stepless shift of a programmed driving program or a characteristic curve A1, which, depending on the accelerator pedal actuating speed, is within the consumption map between a consumption-optimized A1 and a maximum performance-oriented line A4, or in steps or in several individual steps. Characteristic shifts (see Fig. 6f). Thanks to the preferably stepless transmission control, an almost optimal adaptation to the most varied driver requirements can be achieved. The above-mentioned driving program within a lower and an upper limit can also be preselected manually. Also step-by-step programmable individual programs A2; A3; A4 can be implemented sensibly.

The control device in these forms mentioned above allows a largely individual driving style. The driver can here in a simple way according to his wish or according to the driving conditions very quickly Preselect the desired gear ratio, which, as mentioned, a consumption-oriented function or one performance-oriented, sporty function. To the The example of preparation for an overtaking maneuver has Driver the further possibility, first the overdrive area turn off and if necessary with the same aforementioned Actuator via manual operation or by  brief one-time or possibly multiple Accelerator pedaling or tapping - or even a device for lateral foot movement impulses are conceivable - even one further translation provision (towards larger Translation or lower gear) by the Engine speed is raised further, so that at the beginning of Overtaking high to maximum possible engine power quickly is available. To overturn the engine to prevent the above-mentioned further translation provision, according to the invention is an automatic one or the respective one Reset limit programmed for the operating state. In this case, one that is adapted to the operating situation is preferred optimal engine speed set. The definition of this Limit speed points can represent a limit speed line that from aspects of engine speed noise and / or the possible Engine acceleration ability of the respective engine results. The control and regulating device for the transmission itself is here appropriately designed so that after the completion of Overtaking automatically the consumption-oriented program takes effect and the engine returns to the most fuel-efficient Line runs. Accordingly, this function can e.g. B. time or / and depending on load or accelerator pedal dynamics be preprogrammed. If the driver wishes a longer one Persist in the sports program, so it is possible to to call up the corresponding sports program through a separate or common actuator. The alternative or additionally available push button "S" can be used for this purpose be provided with two locking positions, the one locking position for a single acceleration process and the second Rest position is provided for a fixed sports program.

The invention is particularly characterized in that the automatically effective signals for the detection of ascent, Descent, cornering, acceleration, deceleration and Winter operation an automatic, specifically adapted stepless Cause translation change speed.

With regard to a comfortable continuous acceleration process, both with regard to the acceleration performance and the noise behavior, according to the invention an adapted reset damping that is suitable for the different driver types or a delay device for the gear ratio reset in the acceleration process is provided, which, depending on the respective engine acceleration, has an adapted transmission reset allows so that the engine can rev under continuous torque load. This can, on the one hand, via a damping effect programmed in the control unit, adapted to the various accelerator pedal adjustment characteristics or driver characteristics, and / or via a via the hydrostatic pressure signal and / or via a, e.g. B. from the engine load dependent signal size programmed delay signal can be realized. In Fig. 6g and the corresponding adjusting characteristic is Ü1 translation modification; Ü2 shown with slow gas movement and throttle valve adjustment DW1 and faster DW2.

The invention sees - in particular, a tax and Control device before that an automatic stepless Translation adaptation to a wide variety of driving and operating allows situations without additional driver intervention, whereby Driving comfort, driving safety, driving performance, fuel consumption to a high degree. This is in particular the correct translation adjustment and the speed of change stepless translation for the respective driving and Operating conditions are critical. The tax and Control device is influenced by Adjustment speed of the accelerator pedal, by speed difference values of the rear and front wheels and / or signals from the Centrifugal force behavior of the vehicle, e.g. B. when cornering. Further Signals for influencing the translation change can load-dependent signals, e.g. B. the hydrostatic pressure signal d or / and Accelerator pedal or throttle position signal. For The invention sees cornering, depending on the size of the Lateral acceleration, a more or less large damping up Blocking the stepless translation change before, that is If the translation is changed too quickly, this is prevented by the influence of those resulting from the lateral acceleration Signals.

When driving uphill, unpleasant upward and downward rules are caused Detect the uphill from the load signal - hydrostatic  Pressure signal and / or accelerator position signal and the Driving speed or / and from the general Acceleration behavior.

For downhill descent, a gear lock is built in Dependence on the brake pedal and / or from the detection of the Overrun mode is activated. Can be very beneficial for above called functions the signals from the known ABS or / and ASR and others, also known, with braking and relative Drive balancing systems related facilities be used. Use the brake pedal to select the one you want Speed set after releasing the pedal is maintained and acts like a cruise control, primarily the engine brake until reaching a defined engine speed is effective. Can the now selected Driving speed cannot be maintained via the engine brake what is signaled by high engine revs, can by switching on the service brake by renewed Brake actuation another stepless translation Resetting and lowering the driving speed can be effected. When accelerating, the gear lock is dependent on Accelerator pedal actuation speed continuously more or less quickly in the direction of stepless transmission upshifting solved.

The control can also be designed so that when driving downhill without service braking, that is without Brake wear can be driven using a pure motor braking, resulting in automatic speed adjustment or translation adaptation depending on the road profile by appropriate control via the engine speed signal is realized.

For winter operation, the invention provides a driving program that prevents slipping through the fact that the hydrostatic pressure is controlled by a pressure regulator, which is preferably a bypass valve 114 c; 216 ; 233 ; 204 is formed, is modulated automatically, the corresponding control signal 113 ; 217 ; 215 results from one or more of the operating signals such as a load signal, e.g. B. from hydrostatic pressure and / or accelerator pedal position or throttle valve position, speed signal b or / and transmission translation signal and / or manual actuation signal and / and a difference signal from speed signal b and accelerator pedal signal a or / and throttle valve position signal DW. The information for the control is determined and signaled from the tire slip behavior or / and different wheel speeds and speed differences, as a result of which the pressure control automatically changes to an adapted pressure modulation. For this purpose, the signal transmitters already present in the ABS brake system can be used advantageously and inexpensively.

Depending on the driving resistance or grip, the hydrostatic pressure is automatically recognized as a measure of the permissible driving force and modulated accordingly. In a simplified embodiment, a more or less targeted pressure modulation for the hydrostatic pressure can also be generated by a signal from the accelerator pedal movement or position, such that, for. B. the aforementioned pressure control valve or bypass valve, which shorts the two working pressure lines - high pressure, low pressure - with each other with an adapted throttle effect and modulates the working pressure and thus the driving force via the control line 217 by the accelerator pedal movement.

For sensitive, exact adjustability of a constant speed to be selected, the invention provides that the setting speed, until the desired constant speed or constant ratio is reached, causes a rapid change in adjustment in the higher speed or ratio range 1 / i and a slow change in the ratio at low speed. Especially in the lower speed range, a fine adjustment is very important, e.g. B. to be able to maintain a certain creep speed, as is required for tractors. As shown in Fig. 6d, in the high speed range there is a rapid, preferably linear reset until a translation point "Ya" is reached and from point "Ya" to "Za" there is an ever slower adjustment with respect to the adjustment time or the adjustment path . This ensures that the lowest speeds or creep speeds are sensitive and precisely adjustable. The setting according to FIG. 6d corresponds here to a continuously running line 9 a. The line 9 a; 5 a preferably corresponds to a logarithmic curve with increasing limiting or constant speed. According to FIG. 6e, a different course is implemented over three lines 6 a, 7 a, 8 a, which are becoming ever flatter.

These setting characteristics, as shown in Fig. 6d and 6e, can be electronically or via mechanical elements, e.g. B. can be realized via cams or known lever / displacement devices. The adjusting lever can be a separate lever or, analogously, the selector lever 1 a, 2 a. A setting symbol 5 a gives an orientation for the setting variable. Intermediate engagement of the setting or selection lever 1 a, 2 a can be advantageous in some cases for a rough orientation. Also advantageous is a digital display on the instrument panel that can be set manually.

The controls - button 3 a or adjusting lever - can be arranged anywhere in the vehicle. The arrangement of the actuating elements, in a known manner, on the selector lever 1 a, 2 a, such as, for. B. in Fig. 6a and 6b or on the center console. The arrangement of the controls on the steering wheel, FIG. 6c, can also be regarded as user-friendly.

The controls are in any embodiment as Push buttons or rocker switches for preselecting the overdrive Area or for the upper translation area and for the Switch off the overdrive area and at the same time for the Setting a constant speed or a Constant translation can be carried out.

Depending on the type of vehicle and its specific Different driving regulations or Driving programs provided. The type of use of work machines, e.g. B. the tractor, calls for a program consumption - oriented regulation, especially for the Transport company or all types of use in the field without PTO operation with speed limitation makes sense. The engine works by preselecting this program mainly on the best consumption line of the engine. For one Performance-based regulation, on the other hand, is a program provided that primarily on optimal performance utilization  of the drive motor is aligned. It is possible that To equip the vehicle with an additional device that it allows a pre-selectable upper limit of the engine speed to set z. B. unpleasant engine speed noises or also to avoid increased gear motor wear. These The device is also suitable for braking when driving longer downhill gradients, the optimal braking ability of the Engine is exploitable. The engine speed signal is used here expediently adapted the gear ratio accordingly, as described in more detail later.

For PTO operation, there is usually one on the tractor certain constant engine speed required. With area code this PTO operation, according to the invention, automatically with the actuation of the PTO clutch or PTO shift switched to constant engine control (RQV). The driving speed can be according to the driving resistance and within the given at this engine speed Service offers automatically or via a corresponding one Manual adjustment can be adjusted.

For all the driving programs mentioned - consumption-oriented Regulation, performance-oriented regulation, constant motor regulation for PTO operation - is, as mentioned, a separate one Actuator, preferably one for tractors Push button circuit provided. The corresponding signals for the fulfillment of the required functions, such as described in more detail below, preferably in one processed electronic control unit in a known manner. Of the Motor here preferably has a controller that is both a Power control - RQ control - as well Engine speed control or all-speed control - RQV control - has, with z. B. when preselecting the consumption-oriented Operation or transport operation of the well-known RQ controller and Pre-selection of the PTO operation of the well-known RQV controller appeals. Such a motor control is in the magazine "Automobile industry" 5/86 page 653 under the title "EDR electronic diesel control for commercial vehicle engines" closer described. Even when preselecting the defined benefit scheme (RQV) is operating within the certain limits  Best consumption guidelines possible, but with an operating program is provided depending on the respective Operating conditions compliance with the engine speed in predetermined limits, as described in more detail later, prescribes.

Details of the control / regulation are detailed below described and partially lead to improvements in Devices according to European patent application 0 280 757.

For the PTO operation of the tractor, constant engine speed is required, as already mentioned. To make this possible, a motor with speed control - RQV controller - is usually used. When preselecting a certain working speed, it must be possible to change the gear ratio if the engine's power limit is exceeded at this speed. According to the invention, an additional control device is provided in combination with the RQV engine control, which enables the above-mentioned translation adaptation. A certain engine speed variable is assigned to each accelerator pedal position. For this purpose, as shown in Fig. 6i, a signal a depending on the accelerator pedal or hand throttle position is given, z. B. runs parallel to the engine speed signal b and a difference delta s is smaller than the engine speed signal. If a load-dependent depression of the engine speed takes place at a preselected gear ratio setting, the engine speed signal b becomes smaller than the accelerator pedal signal a, whereby a signal for increasing the gear ratio is automatically triggered, so that the engine load and the driving speed are reduced accordingly. The gear ratio is automatically adjusted by comparing the engine speed signal b and the accelerator pedal travel signal a. The accelerator pedal signal is therefore always lower than the engine speed signal. Now, e.g. B. in normal driving without a fixed speed and speed limit by accelerating the engine speed signal exceeded, the gearbox automatically tends to a kick-down effect to a gear ratio reset, so that the engine can take its new speed as quickly as possible. With regard to comfortable driving behavior, the accelerator pedal signal is also corrected here, similar to the RQ control, and entered into the control unit in a delayed form. Depending on the dynamics of the accelerator pedal adjustment, the delay effect is programmed in different sizes, that is to say adapted accordingly. The invention provides various functions for the starting behavior with an RQV-controlled motor. When starting off, as is known per se in automatic transmissions, it is expedient to preselect the direction of travel via the selector lever 108 ; 1 a made with the brake 7 depressed. The brake signal f causes the engine speed signal, which is increased for the starting range, to be reduced by a value which corresponds to the transmission state infinite or to a standstill of the vehicle. When the brake is released, the engine speed signal b, which is increased for the starting state, comes into effect, which triggers a change in the gear ratio for the starting process. A further possibility for the start-up function can be provided by a bypass valve 144 c which acts in the start-up area and is connected between the two working pressure lines and also serves for the winter program, which is opened via the brake pedal and the corresponding control line 113 and is gradually closed when the brake is released. It is also possible to actuate the bypass valve 114 c via the accelerator pedal, as a result of which the bypass function is continuously switched off when the accelerator is accelerated. An adjustable or controllable adjustment lock of the hydrostatic adjustment can also fix the final translation position when the vehicle is stationary. With a view to safe starting behavior, it is expedient to program the control and regulating device so that the preselection of the direction of travel is only possible when the brake is depressed, that is to say that the first range clutch can only be switched when the corresponding brake signal f acts.

This type of control is also advantageous for the normal one Driving control suitable, with neither engine speed nor transmission translation are selected. Every accelerator pedal position is here a certain engine speed and an engine torque, according to the full load torque curve. The Full load torque curve also corresponds to that Best consumption curve of the engine, which means at the same time efficient overall operation is achieved. About the Accelerator pedal is indicated by the engine speed signal and the accelerator pedal  Path signal automatically via the control device Gear ratio set, the full load at this Accelerator pedal position and the one specified by the RQV control Corresponds to engine speed. Accelerator pedal travel signal and engine speed Signal keep the scales via the automatic Translation adjustment. With a view to a pleasant one Acceleration behavior must be taken into account that the The accelerator does not change the gear ratio too quickly in the direction Larger translation is done to avoid uncomfortable engine highs prevent. For this purpose is either in the accelerator travel signal or / and in the transmission adjustment device or / and in Engine speed signal a corresponding delay device programmed or provided that a comfortable Noise behavior of the engine in the acceleration phase ensures.

This type of control described above also enables RQV engine control a comfortable automatic driving control.

As can be seen from FIG. 1, the transmission adjustment is via a signal c resulting from two or more operating signals, in particular engine speed signal b and accelerator pedal signal or engine control signal a or throttle valve angle DW and / or via a so-called EP adjustment, according to FIG. 8, possible with two input signals C1 and C2 for adjusting the hydrostatic transmission. C1 and C2 are electrical variables that act on an electrical adjustment with a proportional magnet and are proportional to the adjustment variable of the hydrostatic unit.

The accelerator pedal signal a can be a throttle valve adjustment signal or can also serve as an engine control signal k, which is connected to the engine via the control unit 5 , the signal k being identical to the accelerator pedal signal or a modulated variable, depending on specific operating parameters, represents.

The invention further relates to a motor vehicle transmission, in particular with power split, which consists of a stepless converter 4 c, according to FIG. 2; 3; 4; 5, preferably a hydrostatic converter which consists of a first and a second hydrostatic unit, with both units preferably form a common structural unit, and drive and / or output of the continuously variable converter 4 c, depending on the embodiment, via direct drive or through intermediate drive wheels. The power is divided on the input side into two power branches, one power branch flowing through the stepless converter and, before the transmission output, possibly summed up again in a summing gear 5 c with the other power branch. Power split transmissions consist of one or more shift ranges. Switching from one area to the other is preferably carried out at one end adjustment point of the hydrostatic unit, the adjustment variable remaining unchanged within the switching phase, with the exception of any minor adjustment corrections. For example, in a 4-range transmission, as shown in FIG. 3, the hydrostat is traversed four times over the entire transmission range from one adjustment maximum to the other adjustment maximum. In this transmission according to FIG. 3, the hydrostat is set to its maximum negative adjustment variable when the clutches K5 and KV are closed and after clutch 1 is closed. To start up, the hydrostatic is now pivoted back to "zero" and beyond to its other end of adjustment, positive adjustment maximum, where at the end of the first and at the beginning of the second shift range with synchronous operation of all clutch elements the second range by closing clutch K2 and opening the clutch K1 the second area is switched. Now the hydrostat is regulated back down to "zero" within the second switching range and furthermore up to its negative adjustment maximum in order to switch the third switching range by closing clutch K3 and opening clutch KV. The third area is then in turn controlled by the hydrostatic control by "zero" and further up to its positive adjustment maximum, where at the end of the third switching range the clutch K4 and the clutch KV and K3 disengaging the fourth area is now engaged in synchronous operation. By regulating the hydrostat back to the opposite adjustment maximum, corresponding to the negative adjustment end of the hydrostat, the hydrostat is driven through fully for the last time until the transmission end point of the transmission is reached. The mechanical power component in this transmission is directed through spur gear stages 26 c and the hydrostatic power component via the gear stage 10 b, the hydrostatic converter 4 c and the drive train 7 c with gear stage 228 to the summation gear 5 c. The summation gear is designed here as a multi-shaft planetary gear P1, in which the mechanical and hydraulic power is added up. In the first and in the second shift range, the mechanical and hydraulic power flows via the second planetary gear P2 with the clutch KV closed. For the reverse range, the first and the second shift range are made possible by engaging the clutch KR by reversing the direction of rotation in the planetary gear P2.

The hydrostatic adjustment maximum mentioned in each case is defined the point at which the circuit in the next driving range takes place, which is not necessarily the adjusting end of the hydrostat must be, but can also be something in front, for example compensate for the load-dependent slip of the hydrostatic transmission can. Also under synchronous operation is the one to be closed Coupling elements not absolute synchronous operation but the Defined synchronous running range, the desired or not deliberate synchronism errors can result from the Switching or range clutches bridged or still included can be.

Gearboxes of this type are according to DE 40 27 724, DE 41 06 746 and PCT / DE 89 00 586, which are part of this invention, described in more detail. The invention provides, inter alia, one improved design of this known transmission.

To improve efficiency, noise behavior or / and to create an effective integrated braking system The invention provides, inter alia, one or more hydrostatic powerless operating points, in particular Fixed translation points to be realized. For this purpose the Hydrostat at one or more operating points in particular in main operating areas appropriately trained facilities switched off or bridged to put it in a powerless state. This shutdown or bridging device is in the form of a Hydrostatic locking device KH or / and an area block circuit or / and a stabilizing device KD  with or without direct drive through without hydrostatic power realized.

Furthermore, the transmission is equipped with a braking device which is operatively connected to the hydrostatic bridging device or translation fixed point circuit and the stepless converter 4 c.

In FIG. 4, a power split transmission with a hydrostatic converter 4 c and a summing gear 5 shown c. The summation gear 5 c can also have the function of a branching gear, which is why the term "summing / branching gear" is used below. The hydrostatic converter consists of a first hydrostatic unit A of adjustable volume and a second hydrostatic unit B, preferably of constant volume. Both hydrostatic units A and B preferably form a common structural unit, which is in drive connection directly or via drive wheels with the drive shaft 1 c and on the opposite side directly via further drive wheels with a summation gear 5 c. The summation gear is preferably designed as a planetary gear, depending on the version, a further gear 5 d, with or without switching devices, for. B. for range switching for switching several driving ranges can be assigned. The output of this transmission is divided into a hydrostatic and a mechanical branch. The hydrostatic power component flows via the drive wheels and intermediate links 227 via the stepless converter 4 c and the drive wheels to the summation gear 5 c. The mechanical branch is passed directly or via intermediate elements into the summation gear 5 c by adding up hydraulic and mechanical power flows and jointly reaching the output shaft 2 c. The continuous transducers or the hydrostatic c 4 is in this case equipped with a hydrostatic bridging means as hydrostatic locking means in the form of a brake or clutch KH, which serves the driving shaft 7 c of the second hydrostatic unit B hold or to the housing 19 c to couple the stepless converter or a fixed transmission part so that the supporting torques known in power split transmissions are preferably supported on the transmission or converter housing via the clutch or brake mentioned in order to relieve the hydrostatic transmission or to keep it torque-free and pressure-free. It is also possible for the hydrostatic shaft 7 c of the hydrostatic unit B through a further, not shown coupling to isolate completely.

The hydrostatic locking device KH has the task of keeping the stepless converter 4 c or the hydrostatic transmission in the hydraulically inoperative operating states with hydrostatic adjustment variable "zero" free of torque or load. This is solved in such a way that the torque support force from the summing / branching gear 5 c at hydrostatic zero position, which is generally in the middle of each shift range, not on the hydrostatic elements but on a corresponding intermediate brake or clutch element with respect to a stationary one Housing part or gear part is supported. In transmissions with several shift ranges, the hydrostatic transmission is run through several times within its full adjustment range, with the hydraulically inoperative state in neutral position, ie with adjustment variable "zero" of the hydrostatic transmission, corresponding to hydrostatic neutral position, occurring within each shift range. This operating point is usually in an important operating range of the vehicle, in which particularly good efficiency is required.

In the power split transmissions mentioned at the beginning DE-A-40 27 724, DE-A-41 06 746 and PCT / DE 89 00 586, which, like already mentioned, are part of this invention, the Adjustment characteristics of the hydrostatic transmission described in more detail.

In order to prevent hydrostatic tension in this neutral adjustment position of the hydrostatic transmission, a bypass valve 114 c is provided, which is connected between the two working pressure lines of the two hydrostatic units A and B. This bypass valve can be operated automatically or manually when the hydrostatic locking device is switched, as a result of which both working pressure lines are depressurized or without differential pressure. The hydrostatic locking device or the clutch / brake KH and the bypass valve are expediently controlled via the same control pressure, but the bypass valve is only activated after the clutch / brake KH is closed in such a way that the pressure feedback after the clutch KH closes the signal or triggers the control pressure to activate the bypass valve. The hydrostatic locking device KH is automatically switchable, e.g. B. depending on a defined dwell time of the transmission in the hydrostatic neutral position, a pre-programmed time variable for this dwell time triggers the corresponding control signal for the hydrostatic locking device. For manual switching, it is preferred to indicate this operating state and the switching possibility to the driver via an optical or acoustic signal. The hydrostatic lock can also be released in various ways, e.g. B. by an accelerator or accelerator pedal signal, that is, when changing the accelerator pedal position or by a load-dependent signal or by various signals that are determined by changing operating values. With regard to optimization of fuel consumption, for. B. the driving control can be designed so that the transmission efficiency line and the best fuel consumption of the engine are stored and the vehicle control system decides depending on the respective operating situation whether the closest transmission ratio point with hydrostatic neutral position should be controlled or not. Depending on the type of vehicle, a further parameter can be saved or programmed as a decision factor depending on the load or noise behavior of the transmission. This can be useful, for example, when used in a car.

The invention further provides the hydraulic Service branch also at the translation points of the Switch off area switching points. That means in the end of the old switching area and at the beginning of the new one Switching range the couplings KB for both areas remain closed and the hydrostat in this adjustment size fixed and set without load, e.g. B. by simultaneous Actuation of the above-mentioned bypass valve or / and an exact one Alignment or correction of the hydrostatic adjustment such that the two hydrostatic working pressure lines are depressurized or are without differential pressure. The performance is in this Switching state is transmitted purely mechanically, specifically via the  Couplings or coupling devices of the two adjacent ones or adjacent switching areas. The switching signals for this Switching can be carried out with the same signals as for the hydrostatic Locking device described, can be realized. At a Gear, e.g. B. with four forward driving ranges are on this Kind of seven fixed translation points with no-load hydrostat switchable.

As mentioned, the invention provides for performance branching gear a stabilizing device KD or Hydrostatic bridging device in front of one or fixed translation settings at several translation points stops at which the hydrostatic power flow can be switched off to further improve efficiency.

As shown in Fig. 4, z. B. the output shaft 2 c via a gear stage 10 b with the drive shaft 1 c via an intermediate shaft 227 by closing a clutch KD in drive connection to put the hydrostatic transmission without load after closing this clutch. For other important transmission points, which have a high operating share, further transmission stages, not shown, with a correspondingly assigned clutch can be provided.

An embodiment according to FIG . B. a stabilization or hydrostatic bridging device, in which a direct drive through, without tooth engagement or tooth-rolling power, between the drive shaft 1 c and output shaft 2 c and thus the converter 4 c and the summing-branching gear 5 by means of a clutch KD c is placed in a no-load condition.

The stabilization device or hydrostatic bypass direction KD is also with two or more couplings executable (not shown) to the stepless converter and to decouple the summation branching gear completely. At Combination with a bypass valve already described or / and a corresponding hydrostatic adjustment device with targeted Adjustment control can do without the second clutch become.  

The clutch for the hydrostatic bridging devices KH; KB; KD is variously executable and may, for example of the hydrostat locking means any KH c on one of the intermediate members or drive elements 7 are arranged c between the second hydrostatic unit B and the summing gear. 5 The KH couplings; KB; KD are preferably designed as a positive coupling as in PCT publication DE-A-87/00 324, DE-A-41 26 650 A1 and in European PCT application DE 88/00 563, which are part of this invention described. The clutch is characterized in particular by the fact that it has form-fit switchable clutch elements with a clutch toothing with or without deflection toothing and that by means of a hydraulically actuatable piston which is displaceably arranged on a clutch carrier, the shifting in synchronous operation or in the synchronous operation range is also possible at a certain relative speed. It is also possible, as described in the known publications mentioned above, to provide additional synchronizing devices. This aforementioned positive coupling has the advantage that it is almost free of drag loss since there are no friction elements. But it is also possible to use the clutch as a friction clutch in the form of a cone clutch, such as. B. shown in DE-A-41 26 650 to use. This clutch can also be largely free of drag loss since the conical effect means that the friction surface is relatively small. Under certain circumstances, the use of a multi-plate clutch in a known design can also be designed meaningfully. Another type of positive coupling with mechanical switching elements, e.g. B. by means of shifting claw, shift sleeve and / or with servo-reinforced shifting elements is, depending on the selected gearbox design, usable. In a form not shown, the clutch KH for the hydrostatic locking device is alternatively arranged in the summation gear 5 c. In the embodiment according to FIG. 2, it is advisable to arrange the clutch KH on a shaft 73 c connected to a traction booster 77 c. Here, traction booster 77 c and clutch KH can be combined into a common structural unit in terms of installation space and cost.

The hydrostat is in all the devices already described for switching off the hydrostatic operation via the bypass valve 114 c; 216 or / and to be set without load by a suitably trained hydrostatic adjustment control.

Through all of the above facilities for switching off the hydrostatic power flow, the transmission loss performance reduced to improve efficiency.

For further efficiency improvement, the hydrostatic converter 4 c is preferably designed in such a way that it can work in the oil-free housing with low feed pressures without splash loss.

According to the invention, the transmission has an integrated brake system, for which purpose the hydrostatic converter 4 c is in operative connection with the above-described converter bridging devices or switchable translation fixed points (see FIG. 4). The hydrostatic transmission 4 c acts here as a hydrostatic pump, the braking energy being passed via working pressure lines and correspondingly assigned switching and control valves 203 , 204 via a heat exchanger 205 . The size of the braking energy determined by the respective operating situation is controlled via the pressure control valve or pressure limiting valve and the hydrostatic adjustment. The braking function is based on the fact that in the braking process the nearest or cheapest switchable fixed translation point is searched for and controlled via the control and regulating device and that after switching the fixed translation point by changing the hydrostatic adjustment a torque on one or on both drive shafts two hydrostatic units A and B is generated, which support the engine braking torque via the corresponding intermediate members 227 , 228 . The pump power generated by the hydrostatic transmission represents the braking energy which is dissipated via the heat exchanger 205 . One or both of the hydrostatic units A and B can act as hydrostatic pumps, depending on the operating situation, the required braking power and / or the type of hydrostatic bridging device KH; KB; KD. If, for example, the fixed translation point is switched via the hydrostatic locking device KH, the pumping capacity of the first hydrostatic unit A can be used. When the transmission fixed point is switched via the range block circuit KB, both hydrostatic units A and B can take effect, double braking energy being able to be absorbed. This can be used at the end of each shift range by closing two range clutches, as mentioned, and also at the end of the last range by closing a lock-up clutch KD. For example, in a power split transmission with four forward driving ranges, four transmission fixed points with the aforementioned double hydrostatic power via the hydrostatic units A and B and a further four transmission fixed points with a braking energy output of a hydrostatic unit A are possible according to the invention. The pressure medium or oil flow generated via the hydrostatic transmission 4 c is passed through a pressure line 206 or 207 , one serving as a high pressure line and the other as a low pressure line for the reflux. A 69434 00070 552 001000280000000200012000285916932300040 0002004417335 00004 69315 feed pump (not shown) ensures constant compensation of the leakage oil losses within the pressure or hydrostatic system.

The functional sequence is as follows:

When the brake is actuated, the closest or cheapest transmission fixed point is adjusted and switched after the gearbox reverse control has been carried out, the hydrostatic gearbox initially being in a no-load state. For example, with fixed translation point via the range block circuit KB, the hydrostatic unit A is generally swung out fully in this state, as a result of which both hydrostatic units keep the corresponding amount of oil in circulation at the same speed without differential pressure within the converter transmission. Only after adjusting the hydrostatic unit A to a smaller volume is the differential oil quantity fed into the brake pressure circuit 206 or 207 . If the adjustment unit A is regulated to adjustment variable "zero", the entire pumping capacity of the second hydrostatic unit B, which is generally designed as a constant unit, is fed into the brake working pressure circuit 206 ; 207 out. If the hydrostatic adjustment is continued by "zero" and beyond, the adjustment unit A also works as a pump, delivering the same pump output as the constant unit B at the end of its adjustment variable, that is to say with a full adjustment volume. In this state, the highest braking energy can be transmitted at twice the pump output, with both units A and B being driven via their drive shafts 7 c and 6 c and associated drive trains 227 , 228 via the braking torque. Both hydrostatic units A and B can also be designed in different sizes, the respective braking powers being different according to their size and their associated speed. If the second hydrostatic unit B is also designed as an adjustment unit, further variations are possible, for example: B. in such a way that both units are adjusted simultaneously or first the unit B and then the unit A, depending on the operating situations, can be sensibly regulated in their adjustment variables. In the known transmission designs mentioned at the outset, it makes sense to design the second hydrostatic unit B as a constant unit. For the operating state in which the transmission fixed point is fixed by the hydrostatic locking device and the clutch KH being closed, braking energy transmission is only possible via the first hydrostatic unit A, which is driven by the corresponding drive train 227 . In most operating situations this is sufficient. In the event of a higher braking energy requirement, this clutch KH can be opened and another ratio fixed point can be actuated very quickly by automatic interaction of the control device. To achieve a continuous brake transition, the invention provides for this to automatically switch on the service brake briefly, so that a smooth, jerk-free braking behavior is ensured over the entire transmission range. If, for example, a change from a fixed translation point KH to a fixed translation point KB is made during the braking phase, the service brake is first activated via the automatic brake control, so that a largely no-load state in the hydrostatic transmission is carried out with simultaneous automatic resetting of the hydrostatic unit A. In accordance with the automatic brake energy consumption via the hydrostatic transmission, the braking effect of the service brake increases continuously. To find the aforementioned fixed translation point KB by controlling the corresponding range block circuit, the hydrostatic transmission is now in the corresponding end position or

Brought final adjustment, after which immediately after completion of the Circuit of the above-mentioned translation fixed point Service brake with simultaneous readjustment of the Hydrostatic transmission and takeover of the hydrostatic Brake performance the service brake is continuously released. This functional sequence can be coordinated accordingly Signal variables from several operating variables such as brake pressure signal, Hydrostatic pressure signal, adjustment signal of the hydrostatic transmission or / and engine speed signal or / and other signals be realized.

The hydrostatic braking device is adjacent to the hydrostatic converter 4 c of a first non-return valve 209, is that directed the flow of oil to the respective high-pressure line 206 and 207 to a first switching valve 203 and a downstream pressure regulating valve 204th The switching valve 203 is switched via an opening signal 214 to release the hydrostatic braking function. The pressure control valve 204 is controlled via a variable control signal 215 , which is dependent on the magnitude of the braking force and determines the hydrostatic pressure. The heat exchanger 205 is arranged downstream of the pressure control valve 204 , which receives the heated oil flowing from the pressure control valve via a corresponding line 217 and re-introduces the cooled liquid into the working pressure circuit of the brake system via a further line 213 and a corresponding check valve 210 .

The invention further provides, according to FIG. 5, a braking device with an energy store 220 . This energy storage device can be an additional device to the above-described hydrostatic braking device. For this purpose, the device additionally has the aforementioned store 220 , a store switching valve 221 , a store drain valve 222 with a corresponding control signal 223 . The inflow takes place via a line 224 and the outflow from the store 220 via a line 225 . A hydraulic accumulator or pressure accumulator is advantageously used as the energy accumulator.

When the storage system is combined with the above-described hydrostatic braking device, the energy store with the braking energy is advantageously first returned and then, triggered by a corresponding pressure signal, the braking energy is returned via the control unit 204 or the pressure control valve via the heat exchanger 205 . It is also possible to control a mixed function, with the storage device and the device responding simultaneously via the cooling system or the heat exchanger 205 , for example in the event of a spontaneous or / and / or very high brake energy accumulation. A correspondingly coordinated braking function for switching by means of a variable signal 223 is possible via the pressure control valve 204 , its control signal 215 from the cooling system and the accumulator filling or control valve 221 and 222 .

The brake control is designed according to the invention so that in Dependence on the actuation force and the braking force or / and a corresponding engine speed to the size of the braking energy assigned. This means that at low braking power Engine speed only slightly and with high braking power Engine speed is raised accordingly more. This is particularly useful in relation to passenger vehicles the noise behavior. In this context, also to the European patent application 0 280 757 A1 and the German Patent application P 43 15 369.0, the co-components of this Invention are pointed out.

The brake control is influenced according to the invention from information from the ABS brake system (anti-lock braking system) or from one or more signals obtainable therefrom, so that a spontaneously effective automatic continuously variable gear adaptation is guaranteed for a targeted adaptation of the torques or the drive power to the particular driving situation to further increase driving safety and driving comfort. The control of the transmission by the brake pedal can be done directly via the hydraulic brake system and / or by electrical means, for. B. transmitted via a potentiometer in the electronic control unit 5 .

The brake control valve unit 201 can be divided as a common structural unit or in the form of individual components, with at least one of the valves 203 ; 204 ; 209 ; 210 is arranged directly on the hydrostatic transmission 4 c, so that the noise behavior can be optimized in particular by the noise-reducing and vibration-reducing hydrostatic bearing device according to the invention. The hydrostatic transmission 4 c is in this case designed as a compact transmission with a variable displacement pump and preferably a constant motor and rotatably supported in the transmission housing 3 by a corresponding bearing device 4 d, the reaction or torque of the hydrostat being supported by an elastic torque arm 4 e, as in the not yet published DE-A-44 01 509.7 described and illustrated in more detail. The connecting lines to the heat exchanger 205 and / or to the energy store 220 are advantageously, at least partially, formed within the transmission housing 3 as movable or elastic intermediate elements (e.g. hoses, sockets) so that the elastic, noise and vibration-reducing hydrostatic bearing device is not closed hinder. The noise development of the brake valves or the hydrostatic braking device 201 is thus effectively dampened to the outside. In particular, the main pressure valve or brake control valve 204 is advantageously firmly connected or integrated to the hydrostatic transmission 4 c here. In the hydrostatic intermediate housing 216 , at least one of these valves 204 ; 203 ; 209 ; 210 or the entire brake valve control 201 can be accommodated or integrated in a space-saving and cost-effective manner. An external attachment of the brake valves to the hydrostat based on a modular design can also make sense, especially for optional equipment options. The electrical control valves for the brake pressure control valve 204 and / or the valve 203 with their control lines 215 and 214 can be useful as separate units, for. B. in a central control block, which are expediently designed as pilot valves and are connected via elastic or motion-independent control lines to the corresponding valve 204 or 203 .

In the transmission embodiment of Fig. 2 is a braking element, preferably as a hydrodynamic retarder 77 c, is provided which serves as a traction amplifier namely in the form that the torque of the second hydrostatic unit B acting as a support moment is increased for the starting range, and the hydrostatic transmission or the second hydrostatic unit B is relieved accordingly. The device can be used for power split systems in which the first driving range also works with power split and, as mentioned, the starting tractive force is dependent on the size of the support torque against the second hydrostatic unit B. This applies e.g. B. for the aforementioned known transmission systems and the system of FIG .

The brake or retarder element 77 c, 82 c for the traction boost is connected to the intermediate shaft 73 c. It can very advantageously be formed as an alternative structural unit in the front cover 61 c in a space-saving manner and inexpensive to manufacture, preferably as a common structural unit with the front cover 61 c. The retarder 77 c can be connected to any link of the drive train 7 c, 73 c of the second hydrostatic unit B (not shown).

The brake or retarder element 77 c serves, as mentioned, as a traction booster in the start-up area, the retarder being actuated via a pressure fluid which can be modulated as a function of the hydrostatic pressure. It is provided according to the invention that the retarder filling is triggered automatically from a certain hydrostatic pressure via the corresponding pressure signal. An additional signal can form a speed signal, which results from the drive speed of the drive shaft 1 c or the drive motor and / or from the speed of the second hydrostatic unit B. Hydrostatic pressure signal and speed signal can form a common control signal for the retarder 77 c. Another applicable signal can also be an adjustment signal of the first hydrostatic unit A, which is used in addition to or instead of the speed signal of the second hydrostatic unit B. The adjustment signal mentioned in connection with the drive speed signal of the motor also represents a variable for the speed signal of the second hydrostatic unit B. The function preselection is automatically determined when the first forward or first reverse range is switched. It is also possible to use this function only optionally, e.g. B. if a corresponding signal, based on the hydrostatic load or the hydrostatic pressure, the need is indicated to the driver via a light or acoustic signal.

The aim of the traction booster is also to be able to dimension the hydrostatic converter 4 c smaller by substantially reducing the dimension-determining start-up loads for the hydrostats.

Instead of the hydro-dynamic retarder 77 c, a friction brake device, for example as a multi-plate clutch, as already described for the hydrostatic locking clutch KH, can be used. The prerequisite here, however, is that the operating point with very high tractive force only rarely occurs and / or that the brake or clutch KH can be fully closed very quickly in order to minimize the wear behavior. In a power split transmission with z. B. four forward driving ranges is the operating point at which the hydrostatic shaft of unit B can be held at a very low speed, at which the maximum tensile forces of the vehicle are mobile. For this reason, it is quite possible to operate this transmission ratio point, which can be switched as the first ratio fixed point, with a friction clutch. A form-fitting clutch, as described in the introduction, preferably with deflection teeth, can also be usefully used, but the circuit can only be switched when the corresponding hydrostatic shaft is at a standstill. In the approach area up to this fixed translation point, the tractive force is generated via the hydrostatic transmission with the corresponding hydrostatic pressure, which can then be relieved after the clutch KH mentioned has been closed. A combination circuit of the hydro-dynamic retarder 77 c with the hydrostatic lock-up clutch KH can also be used in a sensible manner, particularly in vehicles which have very high operation in the lower speed range with high tractive force. The hydro dynamic retarder 77 c is advantageously activated first and the friction clutch KH is switched on in the subsequent process.

According to the invention, the brake control is designed in such a way that a predetermined braking characteristic comes into effect, in such a way that when the brake is actuated, a defined engine torque is initially generated by resetting the gear ratio and correspondingly increasing the engine speed. The service brake only starts to engage after a defined increase in engine speed. B. depending on a corresponding engine speed signal. At the same time or after using the service brake, the described hydrostatic brake can be used by the hydrostatic converter 4 c if necessary, so that a continuous braking operation is given without overwhelming the service brake. The hydrostatic brake device, which is primarily provided as a continuous brake, can also be used here for short-term service braking to protect the brake pads of the service brake system. With regard to an acoustically acceptable braking operation, the engine braking proportion can be kept relatively low according to the invention by using the hydrostatic converter 4 c as a braking system, whereby, as already described, the hydrostatic brake can be used at each transmission fixed point or can be switched on as well.

The brake pressure valve 203 , 204 is advantageously mounted directly on the hydrostatic converter 4 c, which is preferably elastically and noise and vibration-damping in the transmission mounted. This effectively isolates the brake valve noise from the outside. The hydrostatic converter 4 c here advantageously has a three-point bearing with vibration-damping, partially elastic bearing points as described in more detail in DE-A-42 35 728. This patent application is part of this invention.

The hydrostatic brake system above the hydrostatic converter 4 c has, according to the invention, alternatively a warning signal system in the form of a light or acoustic signal, in order to indicate to the non-automated or partially automated version that the service brake is to be operated manually, so that the engine speed is reduced and the gearbox reset for switching to the next smaller operating range or the nearest fixed gear ratio is made possible.

The control and regulating device can, as follows or partly in more detail in European patent application 0 280 757 described, be trained. The control and regulating device possesses to achieve a continuous and optimal Acceleration behavior and for general increase in Driving performance a device that the adjustment speed dosed essentially depending on the load by the adjustment according to the driving situation and the driver's request the maximum power of the drive motor is adapted.

The invention further provides an improvement in switching quality of the gearbox or its equipment according to DE 41 26 650.

A known transmission of this type according to DE 38 38 767 also takes into account to improve the switching quality Volume correction during the switching process. The correction magnitude ver Ratios are in this known gear at all Range switching is the same size. With the subject matter of the invention however, one is the different mechanical Gear ratios or the different Volume correction adapted to area sizes is provided.

In the case of stepless hydrostatic-mechanical branching transmissions, it is characteristic that after each change of range or after each range shift, the hydrostatic units A and B interchange in their function as pumps and motors. The load-dependent speed slip of the hydrostatic transmission or the shaft 5 connected to the hydrostatic unit B has the reverse effect after each range shift, which must be corrected by the adjusting device within the shift phase in order to ensure a smooth shift.

The object of the invention is a switching device, preferred for automatically switchable transmissions, especially for stepless ones Branching gear above type with positive Couplings with or without deflection teeth or friction clutches with conical friction surfaces, as known from DE 41 62 650, or also  with known multi-plate clutches to create the high Switching quality guaranteed without load interruption.

The leakage oil losses of the hydrostatic transmission cause, as mentioned at the outset, an inevitable speed slip of a hydrostatic shaft 7 c. This speed slip has an effect in conjunction with a continuously variable power split transmission with several driving ranges within the range shift, as shown in Fig. 7, that, for example, during train operation to achieve the synchronous state of the clutch to be switched, the variable V alt by the dimension X am Switching point must be greater than the theoretical value in order to reach the synchronizing point of the clutch elements to be switched at switching point S. The adjustment variable or the maximum adjustment volume is to be dimensioned correspondingly large in the gearbox design. Due to the above-mentioned function reversal from pump to motor and vice versa after switching to the next switching range, the speed slip also has the opposite effect, which corresponds to an adjustment correction quantity by the dimension Y and thus to the adjustment variable V. As a rule, the correction values X and Y have different sizes, due to the respective gearbox design and range sizes corresponding to the different sizes of the hydrostatic pressures Δp1 and Δp2 or Δp old and Δp new at the end of the old and start of the new shift range. During the shift phase, the hydrostatic transmission must be corrected in accordance with the load condition by the correction dimension X + Y = Z. According to a switching example as shown in FIG. 7, where B1 means 1 and B2 means 2, the functional sequence is as follows:

With an upshift under load from B1 to B2 this becomes Switch signal to close the new or second one Range clutch triggered as soon as the second Hydrostat unit B coupling link in drive connection with the coupling elements to be switched at switching point S Has reached synchronous operation. The hydrostatic variable "V old" is larger than the theoretical value V by the dimension X th. Now you switch to the new or second area or the closing of the second range clutch after the  Synchronizing pulse, the old or first range clutch remains closed. The hydrostatic adjustment is now by the measure Z regulated back within both closed clutches Position SK1 is reached, after which the signal to open the old or first range coupling. Only after that will the gear ratio with further hydrostatic adjustment further changed to the new or second area drive through.

The different speed slip sizes of the hydrostat gearbox at the end of the old and at the beginning of the new shift area with the correspondingly different individual Adjustment correction variables X and Y for switching optimization to wear, the invention sees one, the respective interpretation adjusted adjustment regulation before, for which Adjustment variable or the displacement volume V new the adjust baren hydrostatic unit A an adjustment or volume correction is effected in terms of size according to the relationship

The correction factor fz represents a magnification factor in relation to the individual correction variable X or Y of the old switching range, from which the total correction variable Z is calculated. The correction factor fz is a fixed value, which is determined by the respective mechanical transmission ratio and can have different sizes for each of the translation fixed points of the individual range shifts. That means that e.g. B. in a four-range transmission, as shown schematically in Fig. 3, with a certain gear or range gradation, for an upshift from range 1 to range 2 (range shift 1/2), the correction factor fz = 1.85, for the Circuit 2/3 = 3.04 and for circuit 3/4 = 2.75. "fz" is thus determined by the size ratio of the individual shift ranges to each other or, as already mentioned, by the specified mechanical ratios, whereby the different pressure ratios of the hydrostatic transmission are defined at the end of the old and at the beginning of the new shift range with the load state remaining the same. The above-mentioned relationship 1 ) is valid for all switching states, whether pulling or pushing or upshifting and downshifting, but in the case of downshifts the total correction quantity Z is not calculated from X but from Y, which is clear from formula 2). For the downshifts z. B. the above-mentioned four-range transmission according to FIG. 8 with the same above-mentioned translation design fixed correction factors fz for example for the range shift 2/1 = 2.17, for the range shift 3/2 = 1.49 and for the range shift 4/3 = 1.57.

After the correction factors fz for both the upshift as well as a fixed ratio for the downshifts represent number, these can be in the control unit or Processor programmed as constant factors, where on the additional costly facilities for the Pressure signals for Δp old and Δp new for the computing process can be dispensed with. Are used to determine the correction factor fz uses the hydrostatic pressures Δp old and Δp new, see above can these with sufficient accuracy both from the Differential pressures as well as from the absolute hydrostatic pressures can be calculated. The relationship mentioned above for the Switching correction assumes sufficient accuracy that the speed slip of the hydrostatic transmission approximates is proportional to the hydrostatic pressure. Should be here, however There are noteworthy, non-proportional differences this will be taken into account accordingly, e.g. B. by a further adjustment of the factor fz or an adjustment in one another factor fk described later.

Taking into account different operating conditions the invention furthermore a correction factor fk before various influencing factors such as type of clutch, plate, Cone, tooth coupling or general friction clutches or / and Oil temperature or / and adjustment speed or / and others Operating influences are taken into account. The volume or adjustment correction is determined here according to the following relationship:

V new = V old - (V old - V theor.) · Fz · fk  

The total correction quantity Z is thereby fixed by a fixed one constant or variable factor fk according to the pre called influencing factors reduced. This means e.g. B. that Opening signal for the old clutch depending on the type of Clutch is triggered sooner or later.

As a further variant for the adjustment correction, it is provided that the hydrostatic pressure Δp old to determine the new one Calibration variable is used, the new calibration variable V being new is newly limited by a pressure signal Δp according to the relationship

Δp new = Δp old · fzp · fk

or as an approximation

p new = p oldfzpfk

where fzp is a constant, fixed in the gearbox design represents the factor that behaves in terms of size according to the relationship

fzp = Δp new / Δp old

The adjustment variable of the hydrostatic transmission is determined by a electrical quantity, e.g. B. as the current value of the proportional valve the hydrostatic adjustment or / and a direct current quantity that from a potentiometer connected to the hydrostat adjustment is signaled. With regard to particularly accurate Adjustment values for the range switching to achieve best possible switching quality, it makes sense, in addition to that for the Hydrostat adjustment required electrical current of the Proportional valves or the purely hydraulic control for the adjustment it makes sense to use the direct hydrostatic Allow adjustment variable by a potentiometer, whereby the current signal from the potentiometer the exact measurement and Offers switching signals for the hydrostatic adjustment device. A Direct transfer of the adjustment variable or the hydrostatic adjustment angle is also known by mechanical or / and hydraulic or electrical means possible, whereby the Switching correction according to the invention can be implemented.

The switching correction described is particularly suitable for stepless power split transmission such as Tie European patents 0 222 108 or 0 386 214 or 0 238 521, the contents of which are an integral part of this invention, described in more detail.  

The circuit diagram according to FIG. 8 and the transmission diagram in FIG. 3 show the schematic structure of a continuously variable power split transmission with the hydrostatic converter 4 c as well as a representation of the control system with the control valves for the range clutches. The transmission has four hydrostatic-mechanical forward and two hydrostatic-mechanical reverse ranges. The gearbox also has a locking device FH in the form of a brake or form-fitting device to protect switching elements of the gearbox from uncontrolled rotation before the engine is started or before a clutch is actuated when the vehicle is at a standstill. In this case, e.g. B. held a ring gear of a planetary gear, for. B. by a spring-loaded gear member, which is automatically switched off after inserting a switching range or after preselection via the selector 108 via an oil pressure against the pressure of the spring as soon as the first forward or reverse range or the corresponding direction of travel is preselected. After starting the engine and with the selector in neutral position, one of the clutches serving for the range shifts, preferably the KV clutch or the KR clutch, is closed in accordance with the invention for the safe standstill of the transmission-side transmission elements. An additional device is a so-called parking lock, in a known form, or a corresponding braking device as a locking device, which locks the output shaft with respect to the transmission housing when the vehicle is at a standstill.

For the hydrostatic braking device or the hydrostatic retarder according to FIG. 4 or energy storage device according to FIG. 5, the invention further provides a device for reducing the noise behavior of the hydrostatic device 4 c by improving one or both of the control disks to improve the noise behavior or control level of the hydrostatic transmission 4 c is / are rotated by a certain angle β depending on various operating parameters, as already shown in FIG. 7 of the known publication DE 39 01 064. The twist signal can preferably be triggered automatically in overrun or braking mode after twisting function, for. B. as described in the aforementioned known publication.

The invention further provides a device for improving the transmission efficiency and also for improving the pollutant emission values, in that the efficiency values of the engine and the transmission (engine map, transmission efficiency map) are stored in the electronics or the control unit 5 and as a source of information for the transmission control to serve. The control and regulating device 5 or the electronics determines the most favorable engine speed for each operating state, taking into account the most favorable efficiency point of the engine and the efficiency point of the transmission, from which the processor 5 determines the most favorable engine speed or the most favorable gear ratio from a corresponding comparison calculation sets.

The invention also has facilities for improvement pollutant emissions, with additional operating parameters, such as air temperature, air pressure, through appropriate sensors and appropriate information is taken into account. To do this the engine speed depending on the operating and Environmental parameters adjusted accordingly, the parameters to determine the best consumption values and the parameters for Optimization of pollutant emissions in the overall determination or Overall calculation are included, from which the cheapest Engine speed or the cheapest continuously variable ratio fixed and automatically via the control and regulating device is set. Since the best consumption point is not always that corresponds to the lowest pollution operating state, it is according to Invention possible to establish a corresponding compromise line and to program, also taking into account Parameters related to driving performance, especially under the aspects of security, e.g. B. to realize a good one Acceleration behavior for fast overtaking or for Realization of general sporty driving style and Exploitability of optimal driving performance.

For starting the engine, especially in the cold state with a drive combination with a continuously variable hydrostatic power split transmission, e.g. B. in a transmission design as shown in Fig. 3, in which the hydrostatic is set to the delivery volume in the start-up state, the invention has a device according to which the vehicle can be brought ready for operation or to operating temperature in an optimally short time. When starting the engine, the hydrostatic transmission 4 c is adjusted in its adjustment volume to zero or to a small adjustment size, so that little or no oil can be delivered to keep the drive torque of the hydrostatic low. The range couplings K1; K2; K3; K4 are open here. In order to be able to bring the hydrostatic adjustment device into the starting position as quickly as possible, in which the corresponding range clutch can be closed, preferably in the synchronous state, the hydrostatic unit is swiveled out depending on the engine speed or the most favorable engine idling speed, the adjustment speed being dependent on the heating speed of the oil , which determines the drive torque of the idling hydrostatic transmission and the engine torque in this operating state. A correspondingly predetermined engine speed, in particular idling speed, determines the rate of adjustment of the hydrostatic device until the starting position is reached before the corresponding range clutch is closed by its signal size. A too fast hydrostatic adjustment would cause excessive engine pressure due to the excessive hydrostatic drive torque, which is dependent on the oil temperature, which is prevented by the engine speed signal mentioned. The area clutch in question is expediently closed only after preselection of the driver. An even faster operational readiness is through additional manual or automatic accelerating, e.g. B. can be achieved by a corresponding start program. Depending on the temperature, a differently sized or adapted idling speed can be programmed in the starting program, high idling speed being associated with low temperature, preferably oil temperature. The operational readiness, in which the hydrostatic transmission is swung out in the starting position, can be indicated by an acoustic or optical signal, the display being effective within the non-operational state or by a brief signal that responds after operational readiness. The starting position of the hydrostatic device, depending on the gearbox design, can be determined with a certain adjustment variable, preferably at the end point of the adjustment. The signal for issuing the hydrostatic transmission to the starting position after starting the engine can also be triggered automatically as a function of the oil temperature and / or as a function of the engine speed and / and as a function of the hydrostatic pressure or differential pressure or other operating influences. The hydrostatic adjustment at zero or smaller adjustment angle when starting the engine is advantageously fixed by a spring lock known per se.

In view of an optimally short switching time for the range shifts, the hydrostatic adjustment device is reversed in the opposite direction immediately after the new range clutch is closed. These, like all of the previously mentioned functions relating to switching time reduction, can be programmed electronically in the control logic in a known manner. The aforementioned hydrostatic control can also be implemented by a corresponding shuttle valve, not shown, which is reversed, for example, as a function of the control pressure pK2 for the second range clutch (see FIG. 7a).

The range clutch K1 to K4 and KV, KR are preferred as positive couplings with or without deflection teeth, such as known from DE-A-39 03 010 and DE-A-41 04 167, educated.

As shown in FIG. 6k, the sum of the signal quantities a + b can be used to form a control signal c both for the RQV and for the RQ control, c also being referred to as the difference signal for the transmission adjustment. As the accelerator pedal travel increases, the accelerator pedal signal a drops, which means that when the accelerator pedal is connected to a potentiometer, the control current for the signal a decreases as the accelerator pedal travel increases. The difference signal "c-soll" preferably forms a constant variable over the entire engine speed range. Every deviation from the control signal "c-soll" leads to an automatic translation change, a deviation in the direction "+" causes a stepless transmission upshift and with "-" a translation reset. In the starting state, the differential signal c is pressed down (-) by the additional influence of the brake pedal signal f to ensure that the vehicle is at a standstill, the starting process being initiated when the brake is released and the brake signal f is released. This type of control has the advantage that the hydrostat adjustment can be carried out inexpensively and, for. B. with only one solenoid valve or proportional valve or solenoid with proportional amplifier can be controlled.

The driving control is principally designed so that engine speed signal b and engine control signal a strive for equilibrium. This means that every deviation leads to a disturbance of the equilibrium, which triggers a corresponding change in gear ratio until the two signals a and b or k and b are in equilibrium again. Signal a or k thus forms the target value and b the actual value effective for the cruise control. The signal a dependent on the accelerator pedal can in this case be a direct signal or a signal modulated in accordance with the consumption-oriented characteristic of the engine, with the engine control preferably being controlled directly via the drive control or a common control device for the engine and transmission, e.g. B. is connected by a control or engine control signal k (see FIG. 6i or 6m).

Another feature of the invention is that after starting the engine before actuating the preselection or driving lever 108, the brake must be actuated, the synchronous state being established before switching the first range clutch K1 via the brake signal or brake actuation signal f means that the function of the selector lever 108 is only effective after the brake has been actuated. In the interaction of engine speed signal b, engine control signal a and brake signal f, a standstill control is activated, the starting process being initiated after releasing the brake and reducing the brake signal f. The signal size for the brake signal f is preferably dependent on the size of the brake actuation force and / or the actuation path. The brake signal f influences the start-up process in such a way that when this signal is reduced or changed, a gear ratio change for starting takes place, a driving speed which is as great as it sets when the brake is released or the brake signal f is reduced to zero Idle power of the engine allows for given driving resistance or that this "idle speed" is limited to a certain minimum speed by an additional signal, which can also be an idle speed signal. For maneuvering operations or for INCH operation, it is possible to program an additional, preferably pre-selectable engine control function which, if necessary, causes the engine speed to be raised automatically in the event that higher tractive forces or higher engine power are required without having to operate the accelerator pedal. This device saves an additional INCH pedal. It is also possible to "inch" or for reversing the engine speed, eg. B. by the hand throttle lever HG to vary or preselect a higher engine speed using the hand throttle. As a further variant, the selector lever 108 can advantageously also be actuated for the INCH and / or reversing operation.

The brake signal f can depend on the brake actuation force and / or more or less dependent on engine speed, where preferably in the lower speed range and Approach area, e.g. B. when releasing the brake, the braking component can be very low or almost zero via the service brake. The brake signal f can therefore depend on the type of vehicle a fixed or according to a certain braking characteristic variably changeable to different operating parameters Represent characteristic curve.

The brake signals 113 ; 217 ; 215 of the braking, control and regulating device for the retarder braking system, preferably hydrostatic retarder, according to FIG. 2; 4; 4a; 5; 6, or a retarder of a known type, can advantageously be directly or indirectly connected to the brake signal f or act as a brake signal f.

The invention further provides for the kick-down effect kd already described at the outset to be designed differently for acceleration processes depending on different operating parameters, preferably according to a constant or variable kick-down characteristic curve kd, as shown in FIG. 6l. The operating parameters mentioned can be: output speed, accelerator or accelerator pedal travel, rate of change of accelerator or accelerator pedal, load conditions, output ratio, vehicle-specific requirements, etc. At low vehicle speed or in the approach area, there is no kick-down effect, but rather here the accelerator pedal position and increase in engine speed a translation change is provided upwards, so that a high or optimal acceleration behavior is possible from the start. When starting after the brake is released or in the starting process, a spontaneous continuous transmission upshift is triggered as a function of the engine speed signal b, which is dimensioned in its adjustment speed so that, depending on the vehicle-specific requirements, e.g. B. depending on the accelerator pedal adjustment speed and / or travel and depending on the driver's wish, there is an acoustically pleasant speed behavior of the engine, with maximum acceleration being usable within the given engine power even in the starting condition or lower speed range.

In vehicles, in particular with speed-controlled internal combustion engines in the manner of an RQV control (with RQV control all RQV-like engine controls included), the difference signal delta s (see Fig. 6i) is a design variable based on the no-load engine, the different Size above the engine speed. Delta s or the target characteristic curve for the accelerator pedal signal a or engine control signal k is preferably designed such that in normal operation the best consumption condition and / or the full load line or / and predetermined operating line is always controlled by appropriate translation adaptation. The signal quantities a; k and b are congruent or seek the balance by adapting the translation accordingly. This allows largely consumption-oriented operation even with RQV engine control. The difference signal delta s is advantageously relatively small in the lower speed or gear ratio range, since the engine pressure required for driving control is not or hardly effective here. Here, an additional signal effective in the approach area can serve as a limiting signal to a minimum approach speed.

The target characteristic curve a; k is a preprogrammed characteristic curve that assigns each accelerator pedal position or each engine control signal size to a certain engine speed and thus power level. Depending on the requirements, this characteristic can correspond to a top consumption line or a performance-oriented line, corresponding to a sports program or one or more characteristic curves in between. The characteristic curves a; k correspond to the characteristic curves A1, A2, A3, A4 shown in FIG. 6f. As already described and also explained later, depending on the type of vehicle and the specific vehicle requirements, the regulation can be designed so that between the two border lines A1 and A4 there is a continuous or step-wise shift depending on different operating parameters and / or depending on the driver characteristics become.

For speed limitation, the invention provides for RQV- or RQV-like motor control with preselected constant Engine speed the relevant limit speed by a corresponding signal, e.g. B. Gear ratio or output speed Limit signal d. When full load is reached automatically as a result of engine pressure and related Falling below the engine speed signal b compared to that with the Accelerator pedal predetermined accelerator pedal signal a or engine control Signal k reduced the translation, so that automatically within the preselected limit speed Speed sets that of the selected full load power corresponds. The engine speed remains according to the Requirements for PDO or PTO operation of a tractor constant.

For applications without the requirement of constant engine speed, e.g. B. for plow or transport operation, the invention further provides a device that causes a consumption-oriented reduction in engine speed after reaching the preselected limit speed. As shown in FIG. 6m, a control line br is used for this purpose, which is assigned to the accelerator pedal signal a or engine control signal k. The signal br corresponds to an upper engine speed, which determines the upper speed limit and thus the control range delta sr. The engine control function is based on the fact that when the upper speed limit is reached or exceeded due to falling driving resistance, a transmission upshift is triggered so that the engine speed can be reduced on the consumption-oriented target characteristic. The accelerator pedal signal a is replaced by the engine control signal k formed in the control device or the electronic control. The engine control signal k is congruent with the engine speed signal br. In operating states in which the driving resistance exceeds the engine power specified by the speed limitation, this driving control, according to FIG. 6m, automatically brings about a gear ratio reduction by means of the inevitably effective engine pressure, such that the engine speed signal br or the accelerator pedal signal a or Motor control signal falls below k and thereby triggers the transmission reset signal or that in the opposite sequence within the scope of the available engine power the engine control signal k and thus the engine power increases accordingly. The increase in engine power can also be adjusted manually by changing the accelerator pedal or the selection device accordingly.

In normal operation without a PDO or PTO circuit, in which there is therefore no constant engine speed requirement, consumption-oriented operation can be carried out in combination with both RQ and RQV-controlled engines at the speed limitation point in partial power operation. The speed is limited by the control via the output speed signal d. As already described, each engine power is assigned a low-consumption engine speed, ie an automatic speed reduction in the part-load range is triggered at the limit speed of the limit point by a corresponding automatic gear change or gear shift. The corresponding control takes place via the setpoint / actual value comparison of the speed signal b or br and the motor control signal k, the corresponding motor control signal k being formed in the control unit or in the electronic processor and as the output signal Internal combustion engine M is supplied. This control is suitable for both RQ and RQV engine control. The control characteristic curve k corresponds, as mentioned, to the consumption-oriented or also a performance-oriented or an intermediate variable characteristic A1; A2; A3; A4 according to FIG. 6f depending on various operating parameters, depending on the vehicle type and / and driver characteristics. This type of control is also possible via the control function, as shown in FIG. 6k, the difference signal c being the sum of the control signals k; a plus b, ie engine control signal plus engine speed signal is formed.

With both control types according to FIG. 6i or FIG. 6k, RQ and RQV-like engine controls can be used.

The speed limit function can be saved or / and interrupted and / or canceled at will by operating the brake pedal or accelerator pedal or one other actuator and retrieved as desired become.

The control characteristic according to FIG. 6m can be used both for RQV and for RQ, that is to say power-controlled motors, preference being given to using a common control and regulating device which is effective for the motor and transmission.

The selection device is designed so that either one Speed limitation with constant motor control for PDO or PTO operation or the speed limit for consumption-oriented operation or normal operation can be switched, e.g. B. by a common or separate actuator, e.g. B. with the PTO circuit becomes constant at the same time speed function selected.

The hydrostatic components are used to improve efficiency A and B operated in an oil-free housing. Furthermore is one speed and / or load-dependent, especially from  Hydrostatic pressure-dependent pressure modulation of the feed and Supply pressure of the transmission is provided, preferably the Stabilizing forces for the hydrostatic cylinder block of the Adjustment unit A and constant unit B via the modulated hydraulic pressure, that is with speed-dependent pressure on the valve plate or the Tax levels are pressed. Furthermore, there is one form-fitting hold-down of the piston sliding shoes installed, spring-dependent and friction loss-related Avoid deterioration in efficiency. Similar Devices are known from DE-A-39 01 064.

In a further embodiment, the hydrostatic brake system is designed such that the pressure relief valve for the hydrostatic pressure between the two high pressure lines 206 and 207 is designed as a high pressure regulator 217 or working pressure regulator and thus as a controllable pressure valve. In braking operation, the braking power flowing through the hydrostatic transmission 4 c is conducted in the form of hydraulic fluid via this pressure control valve 217 and, if appropriate, a correspondingly designed valve system 218 or 218 a to the low-pressure side of the hydrostatic transmission with or without an oil cooler 205 interposed. In view of the fact that the oil temperature is kept within an acceptable range, the braking power is distributed over a correspondingly large amount of oil, that is to say that the pressure control valve 217 may be dependent on a temperature signal and / or a pressure signal and / or other load signal or corresponding operating signals that can be used for this purpose can be controlled, at the same time the oil quantity or brake oil quantity in question, which is passed through the pressure valve or pressure control valve 217 , being adapted by means of a corresponding adjustment variable of the hydrostatic converter 4 c. This means that the hydrostatic adjustment and the high pressure control determine the oil pressure and the oil quantity. The temperature signal results from the more heated oil after the pressure regulator 217 or 215 .

A feed pressure valve 233 maintains the feed pressure. This valve is advantageously designed as a pressure regulating valve in order to enable a variable feed pressure that can be adapted to different operating situations, in particular with a view to improving efficiency. In part-load operation, the pressure control can be influenced, for example, by means of a speed signal and / or other load-dependent signals in order to keep this feed pressure at the lowest possible level in order to minimize the power losses. The pressure regulating valve 235 according to FIG. 4c also fulfills the function of the regulatable pressure valve 233 , the feed pressure being used simultaneously as a control pressure, e.g. B. for clutches. In the low load state, the supply pressure is reduced accordingly in favor of the efficiency.

To achieve the best possible rinsing and cooling effect, the edible oil fed into the hydrostatic system via the feed pump 231 is realized via a feed device 216 , which enables the full amount of oil fed into the hydrostatic system and the hydrostatic circuit becomes. For this purpose, the inlet and outlet openings are as far as possible, or so far apart, that this effect is achieved. As shown in Fig. 4b, the feed and feed into the kidney-shaped oil guide openings 229 of the hydrostatic transmission 4 c follows such that, for. B. the feed at one end and the exit at the other end of the kidney-shaped bridge 229 . A corresponding valve 218 a is designed for this purpose as a shuttle valve, which is controlled via the respective high pressure in the working pressure lines 206 and 207 . The exit oil or the oil flowing back from the hydrostatic system via the oil line 237 can be used to supply the other transmission elements such as clutches and lubrication, the supply pressure for the transmission and the supply pressure being determined via the pressure valve or pressure control valve 235 . The lubrication of the gear elements is advantageously carried out from this oil flow, the z. B. via a throttle or a quantity valve 238 and its pressure is determined via a lubricating pressure valve 236 . The oil cooler 205 is e.g. B. as shown in Fig. 4c, conveniently downstream of the lubrication pressure relief valve 236 . In this circuit diagram, the full amount of cooking oil minus the leakage oil loss and the relatively small amount of lubricating oil is forced through the cooler 205 , as a result of which a correspondingly large and targeted cooling effect can be achieved.

A lubrication pressure valve 236 maintains the lubrication pressure. A safety valve 234 serves to safeguard a maximum permissible oil pressure in the feed pressure system and the corresponding lines 239 . This valve 234 can also have pressure functions that are adjustable in terms of efficiency, within a limited pressure range, the oil pressure depending on the pressure control valve 235 being higher by a differential pressure than the supply pressure generated in the pressure control valve 235 in the lines 237 , 241 .

The transmission is further characterized in that the Hydrostatic transmission can work in the oil-free housing, whereby Losing oil can be avoided. The stabilizing forces of the Hydrostatic elements or the two cylinder blocks for the Hydrostatic units A and B are, as already mentioned, in Dependence on a speed pressure (speed signal) or / and a load-dependent signal (e.g. hydrostatic pressure, accelerator pedal Position, throttle position, degree of filling or others Operating signals) automatically adjusted to avoid unnecessary friction losses on the sliding surfaces of the hydrostatic elements, such as sliding shoes and Tax levels, to prevent.

The control and regulating device of the vehicle and / or the Transmission according to the invention has a device for Driver type recognition in addition to the facilities already mentioned alternatively or additionally is designed so that one on the Driver program tailored to individual program (1 program) can be preselected manually or automatically. This program preferably includes a device with one or more different driving programs between an extremely economic (eco program) and an extremely sporty one Program (S program) a variety of program options makes it feasible. Depending on the driver type or characteristic This individual program is the driver's driving behavior available or preselectable, e.g. B. by manual adjustment, about in the form that one with a name tag labeled push button is actuated or an automatic  Setting this individual program, e.g. B. by the automatic seat adjustment and / or adjustment of the steering wheel or other, assigned to the driver concerned Related settings.

The driving program also provides, in addition to good acceleration ability in various operating situations, the utilization of the consumption orientation, such that, for. B. for a certain driver type, the consumption-oriented (eco program) or extremely consumption-oriented program is automatically controlled depending on a time behavior of a steady state in a certain operating state, for. B. at a constant speed drive, from which the driving control or control logic concludes that this state should be maintained longer and accordingly leads the engine speed to the best consumption line or as close as possible to the best consumption line. In preparation, e.g. B. for an overtaking, this "Eco program" is briefly left or briefly deviated from it more or less by manual operation, for. B. by accelerating quickly (accelerator pedal signal) via accelerator pedal adjustment speed or other previously mentioned manual actuation or by arbitrarily increasing the engine speed at almost the same driving speed, e.g. B. by an actuation button or a lever on the steering wheel or in another place, such as. B. in Fig. 6a to 6c.

The "Eco program" is dependent on certain Steady states can be switched on quickly or gradually, whereby also an individual driver-dependent one Pre-programming is possible, such as that z. B. the Activation of the "Eco program" in the form of a gradual Transition from "sport to eco state". The The rate of change depends on the size of the Persistence times at constant speed or after Rates of change that may depend on Road or / and load profile.

The continuously variable power split transmission according to the invention further provides that between the two working pressure lines 206 and 207 of the hydrostatic converter, within the range shift from the higher shift range to the next lower shift range, to improve the range shifts, particularly in the lower speed range, preferably in braking and / or overrun mode 4 c switched bypass valve 216 ; 214 ; 215 responds or is controlled in order to prevent a possibly inharmonic interaction of the service brake against the transmission within the shift phase. The bypass function can also respond within a larger speed range even outside a range switch, in order to prevent a possible counteraction by the drive train - engine, transmission - when the vehicle is braked via the service brake. Here, a complete or partial drive shutdown is automatically effected by the bypass function mentioned. The bypass valve mentioned can be designed as a non-controllable or controllable valve or pressure valve. If it is designed in the form of a control valve, there is the possibility of causing a more or less targeted partial shutdown of the drive train - motor and drive wheels - whereby a differential pressure between the two working pressure lines 206 and 207 is preferably maintained or set. The size of the aforementioned differential pressure and its pressure curve determine the remaining drive component via the transmission. With regard to high switching quality in braking operation, the regulation of this bypass pressure valve 216 ; 214 ; 215 for an adapted continuous pressure curve. Subsequent, targeted gear ratio adaptation, in particular after braking operation or / and coasting operation has been completed, is preferably achieved via the speed comparison device, as already mentioned earlier, by having the bypass function performed by the corresponding control or, respectively, the gear ratio after the driving speed has been matched Control signals, preferably with a continuous pressure curve, are switched off. The continuous pressure curve mentioned can also be used as a control signal for the corresponding translation adaptation. A brake signal, which is preferably triggered via the brake pedal, can also serve as a control signal or additional control signal for controlling the bypass valve.

This way it is possible to get one in certain Difficult, targeted tracking of operational situations Balance gear ratio. Also an unnecessarily high one Load on the coupling links due to the interaction of Gearbox and brake are avoided at the same time Maintaining a continuous comfortable and deceleration-free deceleration behavior of the vehicle. These The aforementioned bypass functions may depend on the Vehicle type, especially when braking hard, especially be advantageous in the event of full braking.

Another or additional braking device provides that depending on the size of the required vehicle deceleration or Braking strength in the event of excessive interaction between gearbox and Brake opens the relevant range clutch to the transmission through drive during the braking phase or up to Switch off vehicle standstill. This can be particularly the case with full braking may be necessary.

The bypass valve 216 ; 114 c; 217 ; 233 ; 214 ; 215 can also serve as a brake valve for hydrostatic retarder operation and as a pressure relief valve for the hydrostatic 4 c. The bypass valve described is preferably designed as a pressure valve or pressure control valve, which is not necessarily designed as a bypass valve but also as a pressure valve so that the overflowing oil in the event that only small amounts of oil or differential oil quantities occur, directly into the oil sump with or without an intermediate oil cooler can be directed.

Another improvement in range switching within the Braking and / or pushing operation is achieved by the Combination of the transmission-side braking via the influence of the Brake signal on the gear ratio and the interaction with the bypass valve described. By the influence of the brake the engine speed is raised due to the signals corresponding gear ratio change, whereby the spontaneity of the switching processes and the Adjustment speeds is positively influenced by  higher speed control pressures and control oil quantity, both for the Hydrostat adjustment as well as for the clutch switching elements is improved. By the interaction of the brake signal, Gear ratio signal and / or engine speed signal or / and if necessary, an automatic filling or Throttle valve position signal and other if necessary Operating signals will be a harmonious comfortable Range switching, even in extreme braking and pushing situations achieved. For this, the braking components are automatically via the normal service brake system and the transmission brake like this dosed that a counteraction of gear and operation brake is prevented by an appropriately adapted Dosage of service brake and gearbox or retarder Braking system achieved through active connections of the aforementioned signals becomes. The proportion of engine braking is metered so that the Engine noise remains within an acceptable range. To the For example, at very low speeds, the Engine braking power very low despite relatively high braking force be, where appropriate a corresponding engine speed control depending on the driving speed or / and the gear ratio or / and the brake size can be preprogrammed. This is advantageous because because at low speed the one to be supported by the engine Relative transmission ratio, even at low engine speeds is large due to the correspondingly large gear ratio. The invention provides for an engine speed reduction with preferably continuous with the vehicle deceleration or with falling driving speed within the Pre-program braking operation.

With regard to a comfortable braking behavior, especially in the lowest speed range, it makes sense to design the function of the bypass valve 216 , 114 c, 217 , 216 , 233 , 214 , 215 such that a minimum differential pressure between the two working pressure lines 206 and 207 is maintained in order to enable a translation tracking via the stepless control within the braking phase, such that after the bypass valve or pressure valve responds, a minimum braking portion remains effective via the transmission. This is particularly important when the transmission control has to go through a shift phase from a higher to a lower shift range, whereby the continuous change in gear ratio is briefly interrupted.

Claims (79)

1. Hydrostatic-mechanical power split transmission with preferably several shift ranges consisting of a continuously variable hydrostatic converter ( 4 c) with a first hydrostatic unit (A) adjustable volume and a second hydrostatic unit (B) preferably constant volume and a power split device in which the drive power is divided is divided into a hydraulic and a mechanical branch, which is summed up again in front of the transmission output, the stepless converter being driven by the drive shaft directly or via intermediate links or intermediate gear stages and being in drive connection with a branching / summing transmission ( 5 c), characterized in that one or more hydrostatic bridging devices are provided, such that one or more transmission fixed points can be switched and that the bridging device in the form of a hydrostatic locking device (KH) for the second hydrostatic unit (B ) or / and in the form of a range block circuit (KB) or / and in the form of a stabilization device (KD) with a purely mechanical drive and that the fixed translation point (s) can be switched manually or automatically. 2. Transmission according to one of the preambles of the claims, characterized in that one or more hydrostat bridging devices are provided such that one or more translation fixed points are switchable and that the bridging device in the form of a hydrostatic locking device (KH) for the second hydrostatic unit (B) and / and in the form of an area block circuit (KB) or / and in the form of a stabilization device (KD) with a purely mechanical through-drive and that the fixed translation point (s) can be switched manually or automatically and that the hydrostatic one Converter ( 4 c) is effective and controllable as a hydrostatic brake retarder at a switched transmission fixed point. 3. Transmission according to the preamble of claim 1, characterized in that one or more switchable translation fixed points and an energy storage system is provided, the hydrostatic converter ( 4 c) at a switched translation fixed point (KH; KB; KD) is so controllable that braking energy can be recovered in a suitably designed storage ( 220 ), the energy storage system having a storage as a hydraulic storage or pressure storage ( 220 ) or as a flywheel storage or as an electrical storage, in the braking energy, thrust energy or drive energy is storable. 4. Transmission according to one of the preambles of the claims, characterized in that the automatically effective signals for the detection of ascent, Descent, cornering, acceleration, deceleration and an automatic, specifically adapted winter operation stepless translation change and / or change effect speed. 5. Transmission according to one of claims 1 to 4, characterized in that the hydrostatic power split transmission is designed that within a switching range of the hydrostatic one negative end position to a positive end position in im next subsequent switching range from its positive is brought to the negative end position or vice versa, whereby within the switching phase of closed new and closed old clutch with the hydrostatic adjustment Exception for possible adjustment corrections remains unchanged means that the hydrostatic transmission after the new one is closed Range clutch in the new switching range in the opposite direction is reversed. 6. Transmission according to one or more of claims 1 to 5, characterized in that the braking system is equipped with or without an energy store ( 220 ), the brake control being designed in such a way that the braking energy is optionally provided via the heat exchanger ( 205 ) flows or is supplied to the energy store ( 220 ), or that in a predefined or programmed characteristic the energy store is first filled and then, depending on a certain degree of filling, preferably further braking energy is dissipated via the heat exchanger ( 205 ). 7. Transmission according to one or more of claims 1 to 6, characterized in that the hydrostatic brake system ( 201 ; 201 A) is equipped with a control device ( 214 , 215 , 203 , 204 ), which, when the translation fixed point is switched, via corresponding control signals ( 214 , 215 ) causes a continuous adjustment of the hydrostatic transmission or the stepless converter ( 4 c), such that the drive train ( 227 ) connected to the hydrostatic unit (A) and / or via the drive train connected to the second hydrostatic unit (B) Drivetrain ( 10 b) a torque that supports the engine braking torque is brought about on the input shaft ( 1 c) of the transmission and that braking energy is transmitted to the stepless converter via one or both of the aforementioned drivetrains ( 227 , 228 ) and via the heat exchanger ( 205 ) or / and is passed to the energy store ( 220 ). 8. Transmission according to one or more of the claims, characterized in that the brake control preferably via an electronic control device after brake actuation via hand or foot actuation via various operating signals, such as load-dependent signal (s), engine speed signal (b) and / or filling signal or throttle valves -Position signal (DW) and / or adjustment signal of the converter ( 4 c) or / and translation signal of the transmission or / and brake pressure signal of the service brake (f), can be influenced or regulated. 9. Transmission according to one or more of the claims, characterized in that the following braking functions are effective in the following order:

• a) brake signal (f) causes gear ratio reset so that a predetermined, defined engine braking torque and / or engine speed is built up;
• b) control device controls nearest or cheapest translation fixed point (KH; KB; KD);
• c) after switching the fixed gear ratio, the hydrostatic adjustment is made to support the engine braking torque;
• d) if necessary, engaging the service brake or increasing the service brake share or / and
• e) if necessary, further reduction to lower vehicle speed depending on the driver's request or the brake application.

10. Transmission according to one or more of the claims, characterized in that a control program for the braking operation is provided which makes the change in the transmission ratio dependent on the engine braking torque or a defined engine speed and thrust speed, such that the Engine speed signal (b) determines the braking proportion of the retarder ( 201 ) or / and the service brake or / and the E-storage device ( 201 A). 11. Transmission according to one or more of the claims, characterized in that in the brake operation during a shift change from one to the other Fixed gear ratio, the service brake, automatic or manually operated, the braking operation in whole or in part Transition phase takes over and that with manual switching acoustic or optical signal the changeover time Driver signals. 12. Transmission according to one or more of the claims, characterized in that with permanent Braking operation a constant or variable thrust speed or / and braking performance with or without automatic Speed adjustment is adjustable and that every motor speed in overrun a certain braking power ratio from engine brake, if necessary retarder or / and E-memory and, if necessary, service brake is assigned. 13. Transmission according to one or more of the claims, characterized in that at Berg down a set continuous braking speed without braking  operation is durable and that for slower speed the brake pedal is pressed again and if desired Speed increase via the accelerator pedal a continuous Release the brake system with simultaneous continuous stepless change in gear ratio is connected, especially with integrated hydrostatic retarder the engine speed or the engine torque is reduced and without Hydrostat retarder primarily the service brake share itself decreased. 14. Transmission according to one or more of the claims, characterized in that in Braking a translation lock device in the direction higher speed takes effect with or without dependency to a certain engine speed or to a certain one Engine braking torque, whereby when the accelerator pedal is pressed subsequent speed increase the translation Locking device depending on the accelerator pedal Speed and / or the accelerator pedal position accordingly quickly releases or the translation of the accelerator pedal movement changed accordingly in the direction of higher speed. 15. Transmission according to one or more of the claims, characterized in that a hydrostatic bridging device or fixed point circuit is provided in the form of a range block circuit (KB), such that within a range shift phase at the end and at the beginning of two adjacent shift ranges, both range clutches for the old and the new switching range remains closed and / or that a further hydrostatic bypass device is provided as a stabilizing device (KD) in the form of a direct drive, which is designed such that the hydrostatic converter ( 4 c) and the summation / branching gear ( 5 c) are bridged and set in a torque-free manner, which keeps a translation point stable in one or more transmission points by engaging at least one clutch (KD) as long as no translation change is required. 16. Transmission according to one or more of the claims, characterized in that the hydrostatic converter ( 4 c) for the hydrostatic locking device (KH) and / or area block switching device (KB) and / or stabilizing device (KD) with a bypass valve ( 114 c) is equipped, which is connected between the working pressure lines of the two hydrostatic units A / B and can be switched automatically after closing one of the clutches (KH; KB; KD) and short-circuits both pressure lines. 17. Transmission according to one or more of the claims characterized in that the Switching device for the fixed translation circuit (KH; KB; KD) as a friction clutch, e.g. B. as a multi-plate or cone clutch or as a form-fitting coupling with or without deflection teeth is trained manually or automatically at speed "Zero" or in the synchronous state or at low Differential speeds can be switched, preferably the Hydrostatic bridging device (KH; KB; KD) with one positively switchable clutch is equipped, which means one arranged on a clutch carrier rotatably hydraulically actuated piston is switchable, which Coupling profile is preferably designed as deflection teeth. 18. Transmission according to one or more of the claims characterized in that the Hydrostatic lock device (KH) and / or area block switch device (KB) and / or stabilizing device (KD) is automatically switchable, the switching signal in Dependency of one or more operating signals Translation signal, load signal, motor or hydrostatic, Translation rate of change u. a. - automatically is triggered and that the automatic control of a Fixed translation point (KH; KB; KD) is programmed so that after a defined dwell time of the hydrostatic adjustment near or in the area of one of these switching points or Fixed translation points are triggered automatically. 19. Gearbox according to one or more of the claims, characterized in that the clutch or brake (KH) of the hydrostatic locking device with the hydrostatic shaft ( 7 c) or one of the drive shafts between the hydrostatic unit (B) and the summation gear ( 5 c ) are connected, is in operative connection. 20. Transmission according to one or more of the claims, characterized in that the Control signal for actuating the bypass valve from the Closing process of the corresponding area coupling or from the Closing process of the corresponding hydrostatic bypass furnishing results and a follow-up function from these represents switching operations. 21. Transmission according to one or more of the claims, characterized in that the Fixed translation point circuit (KH; KB; KD) automatically solved is by one or more operating signals, such as. B. Accelerator pedal signal, load signal, hydrostatic pressure signal, speed speed change signal, brake signal, engine speed signal. 22. Transmission according to one or more of the claims, characterized in that a stabilizing device by closing a clutch (KD) produces a direct drive through between the drive shaft ( 1 c) and output shaft ( 2 c), or that the transmission drive shaft ( 1 c) and transmission output shaft ( 2 c) are arranged coaxially to one another and a purely mechanical power flow via gear stages ( 10 b) and an intermediate shaft ( 227 ) takes place via a stabilizing device when a clutch is closed (KD; 110 ). 23. Transmission according to one of the preambles of the claims, characterized in that a tensile force amplifier in the form of a braking element (retarder 77 c; hydrostatic locking device KH) is provided which directly or with the drive shaft ( 7 c) of the second hydrostatic unit (B) is in drive connection via intermediate links ( 73 c) and serves to amplify the support torque on the second hydrostatic unit (B) in the starting area of the vehicle, the traction booster ( 77 c; KH) preferably manually or automatically via a pressure signal from the hydrostatic transmission and / or a speed signal or / and an adjustment signal can be controlled and that the traction force amplifier is designed as a braking element in the form of a hydrodynamic retarder or electrical retarder and / or as a friction brake ( 77 c). 24. Transmission according to one or more of the claims, characterized in that a Dialing device is provided by dialing code automatic switching of the hydrostatic bridging devices (KH; KB; KD) according to a defined characteristic or that the corresponding hydrostat Bridging device at the relevant operating point or Translation point can be controlled manually, the Switching off preferably automatically depending on or several operating parameters or signals such as engine speed signal (b), load signal from engine or hydrostat, accelerator signal (a), Brake signal (f) takes place. 25. Hydrostatic-mechanical power split transmission, in particular for motor vehicles with two or more switching ranges with a first hydrostatic unit (A) adjustable volume and a second hydrostatic unit (B), preferably constant volume, with a summation planetary gear for summing up the hydraulic and mechanical power and two or several shifting clutches for shifting without interrupting the load of the shift ranges mentioned above, the range change taking place at the synchronous speed of the clutch elements to be shifted and the hydrostatic units (A and B) interchanging their functions as pumps and motors with each range change, and an adjustment correction of the hydrostatic transmission taking place during the shifting phase, characterized in that the adjustment correction represents a function of the hydrostatic load at the end of the old and at the beginning of the new switching range and behaves in terms of size according to the relationship V new = V old - (V alt - V theor.) · fz where fz is a fixed correction factor and behaves in terms of size according to the relationship 26. Transmission according to claim 25, characterized in that the size the adjustment correction additionally by a factor fk can be changed depending on various influencing factors such as clutch opening period and / or oil temperature or / and adjustment speed or / and others Operating factors, the following relationship being valid V new = V old - (V old - V theor.) · Fz · fk 27. Transmission according to the preamble of claim 25, characterized in that the adjustment correction is a function of the hydrostatic load at the end of the old and at the beginning of the new shift range and is determined by a pressure signal p alt of the hydrostatic transmission ( 4 c), the new adjustment variable V new is determined by means of a calculated pressure signal p new, according to the relationship p new = p old · fzp · fkals as an approximate value or precisely according to the relationship Δp new = Δp old · fzp · fkw, where fzp defines a constant in the gearbox design
Represents factor that behaves in size according to the relationship 28. Transmission according to one or more of the preambles of the claims, characterized in that for setting a desired constant speed or constant translation, the adjustment speed of the transmission with respect to the response time (t) or the adjustment path (s) at a higher vehicle speed or at a higher gear ratio 1 / i is larger and 1 / i is smaller with a low vehicle speed or with a smaller transmission ratio ( FIGS. 6d, 6e). 29. Transmission according to one or more of the claims, characterized in that the operating device is designed so that either an overdrive area or consumption-oriented program can be switched on and off and after switching off the overdrive area by further actuation a further stepless translation provision is stepless to further increase the engine speed, an automatically or by brake actuation effective engine speed limiting device protects the engine from undesirable high speed or overturns by manual or automatic switching on or on of the braking device, e.g. B. the hydrostatic retarder ( 201 ) and / or the energy storage device ( 201 A) and / or the service brake ( 26 A), z. B. on the engine speed signal (b) and / and the brake actuation signal (f) trigger the aforementioned braking functions. 30. Transmission according to one of the preambles of the claims, characterized in that a Operating device is provided, in which either RQV regulation, e.g. B. for work with activated power take-off or the PTO on the tractor or the RQ control for one consumption-oriented program is switchable or preselectable. 31. Transmission according to one of the preambles of the claims, characterized in that a driving program is provided for different driving situations, which is based on a characteristic curve which can be shifted continuously within a consumption-optimal limit (A1) and a performance-optimal limit (A4) , The stepless shift is dependent on the accelerator pedal actuating speed or on the driver dynamics and the characteristic curve is shifted so that a higher engine speed level in favor of a higher excess torque, i.e. in favor of higher driving power shifts in the sense of a very high adjustment speed of the accelerator pedal sporty, dynamic driving behavior and with slow accelerator pedal adjustment, the characteristic curve shifts in the direction of fuel-efficient operation and that, depending on the accelerator pedal dynamics, a correspondingly adapted more or less large deceleration effect for one or more rere of the operating signals - engine speed signal and / or reset speed translation - comes into effect, so that a comfortable acceleration behavior, in particular with regard to engine noise, is ensured, or that instead of the automatic characteristic shift alternatively a manually operable stepless program setting, e.g. B. via push buttons or rocker buttons ( 3 a) or by special accelerator pedal movement is adjustable or preselectable. 32. Transmission according to one or more of the claims, characterized in that the on-off function for the overdrive or the consumption-oriented program is triggered by briefly tapping the corresponding actuation button ( 3 a) and that the desired translation size by continuous actuation until it is reached of the desired constant value is continuously adjustable. 33. Transmission according to one of claims 1 to 32, in particular according to one of the preambles of claims 1 and 25, characterized in that an effective translation locking device is provided when driving downhill after operating the brake, the gear ratio being changed in the braking process in this way that engine braking comes into effect and that after releasing the brake pedal ( 7 ) a gear lock is activated in the direction of a smaller gear ratio and only after the accelerator pedal ( 6 ) is actuated does the gear lock continuously according to a pre-programmed characteristic and / or the actuation speed and / or the actuation path of the Accelerator or accelerator pedal is released. 34. Transmission according to one or more of the claims, characterized in that the brake control is designed so that the brake actuation force and / or the actuation path is assigned a defined engine speed or a defined engine braking torque and that a brake force distribution on the engine brake, service brake or / and retarder brake is determined according to a predetermined program ( FIG. 6h). 35. Hydrostatic-mechanical power split transmission, especially for motor vehicles with two or more shift ranges with a first hydrostatic unit (A) adjustable volume and a second hydrostatic unit (B) preferably constant volume with a summation planetary gear for summing up the hydraulic and mechanical power with a control and Control device, the control / regulation preferably working via an electronic processor, characterized by the following features:

• a) Engine speed signal (b), accelerator pedal signal or engine control signal (a; k) and possibly brake signal or brake actuation signal (f) determine the transmission ratio.
• b) Direction of travel or driving preselection takes place via the selector device or driving lever ( 8 ; 108 ) when the brake is actuated under the influence of the brake signal (f), whereby or after which synchronous state for the first range clutch and the switching pulse for closing this clutch (K1) is triggered .
• c) Starting by releasing the brake and the associated change in the size of the brake signal (f), the starting control being activated by the interaction of engine speed signal (b), accelerator pedal or engine control signal (a; k) and brake signal (f) becomes.

36. Transmission according to claim 35, characterized in that the brake signal (f) represents a control signal that depending on the brake actuation or separate hand or foot actuation a translation down-regulation or downshift is triggered, preferably one or both of the signal sizes or signal lines of engine speed and accelerator, accelerator or engine control signal (a; k) are overridden or shifted and that the control signal (f) is a dependent variable for the braking actuating force but an independent or dependent variable for the braking force or Service brake can have or that the control signal (f) is an auxiliary signal that can be effective independently of the brake actuation by a separate actuation device and / or that the signal (f) indirectly or directly in operative connection with a bypass valve ( 114 c; 216 ; 233 ; 204 ) which is arranged between the two working pressure lines ( 206 , 207 ) of the hydrostatic transmission ( 4 c) t is and via a corresponding regulating or control signal ( 113 ; 217 ; 215 ) stands. 37. Transmission according to one of the preceding claims, in particular according to claim 35, characterized in that that over the accelerator pedal (F) without the influence of Signal (f) increases the driving speed at the driver's request is, accelerator pedal signal or engine control signal (a; k) and Engine speed signal (b) depending on the driving resistance Gear ratio automatically to a gear ratio adjust one by the accelerator pedal (F) or the throttle (HG) corresponds to predetermined, constant engine power, where the change in gear ratio by the engine speed signal (b) is determined. 38. Transmission according to claim 35, characterized in that a translation change to Change the approach or inch speed so far takes place as the engine power at idle speed allows or that a corresponding start-up / inch characteristic is preprogrammed so that an automatic engine power or / and Speed increase within a predetermined possibly selectable limit, for example for inching the vehicle or for sensitive shunting work without the need to operate the Accelerator pedal (F) is effective, preferably one Engine pressure through automatically effective influence on the Motor control prevents or limits or automatically Speed is raised. 39. Transmission according to one or more of the preceding claims, characterized in that a kick-down effect is provided which, when the accelerator pedal (F) is actuated, causes a stepless step-down ratio control, the feedback control or kick-down effect after a pre-programmed Characteristic (kd; Fig. 6l) is effective, the feedback control or kick-down effect (kd) increases with increasing driving speed and is low or ineffective in the lowest speed range or that in the starting and lower speed range (from v = 0 to PK) the kick-down effect (kd) has the opposite effect and a transmission upshift or upshift is triggered with increasing accelerator pedal travel or accelerator pedal manipulated variable. 40. Transmission according to one or more of claims 1 to 39, characterized in that the kick down or reverse regulation effect through a pre-programmed Delay effect, preferably after a kick-down characteristic (kd) is influenced, so that a too fast Gear back regulation is prevented, so that the respective Continuous tractive force curve adapted to operating conditions is maintained within the acceleration phase, where the size of the delay effect by one or more Operating variables (e.g. output driving speed, load signal, Accelerator pedal actuation speed, engine speed, Throttle valve position signal, translation signal, thrust or Train operation u. a.) can be influenced. 41. Transmission according to one or more of claims 1 to 40, characterized in that the kick-down effect (kd) runs according to a pre-programmed continuously running line of action depending on the driving speed or the respective output speed, this line preferably depending on one or more operating parameters can be changed or preselected automatically or manually ( Fig. 6l). 42. Transmission according to one or more of claims 35 to 41, characterized in that the Driving control is influenced by the brake signal (f), such that that when the brake is applied, the service brake and / or the Engine brake and / or the retarder not or only partially effective the upper limit of the engine braking speed is the proportion the service brake and this upper limit after a preprogrammed characteristics that depend on to one or more operating parameters, such as speed, Braking force, actuating force u. a., exhibits variable behavior. 43. Transmission according to one or more of claims 1 to 42, characterized in that the Difference signal (delta s) represents a controlled variable, which as  Design size or, in the case of RQV-controlled motor, the no-load Motor operation is assigned size, the difference signal (delta s) is such that when the engine is at full load Engine speed signal (b) and accelerator pedal or engine control signal (a; k) congruent, d. H. are in balance or / and that the difference signal (delta s) or the signal quantities (a and b or a; k and b) is / are dimensioned so that each accelerator pedal Position a certain engine power at a certain Engine speed, preferably low fuel consumption, assigned. 44. Transmission according to one or more of claims 1 to 43, characterized in that a Speed limiting device with preselected or Preselectable constant engine speed is switchable with preferred speed-controlled motor, in particular with RQV control, wherein in the driving control device when the full load limit is exceeded of the engine is a target / actual value comparison between an accelerator pedal Signal (a) or engine control signal (k) and an engine speed Signal (b) takes place, with a preselected constant Engine speed or target speed and load-dependent Engine speed pressure below the specified target Engine speed a reduction ratio and thus associated corresponding reduction in driving speed is triggered. 45. Transmission according to one or more of the preambles of the claims, characterized in that a speed limit is switchable, which is controlled via a speed or output speed signal (d), such that when the predetermined full load power is exceeded at the limit point by target - / Actual value comparison of the signal variables (a and b or k and b) an automatic gear ratio downshift and the associated speed deceleration is brought about and that in partial power operation at the speed limitation point a reduction in engine speed to low-consumption characteristic values and Corresponding transmission upshift is triggered by the fact that automatically the engine control signal (k) changes accordingly by changing the engine speed signal (b or br), whereby

• a) in conjunction with a speed-controlled or RQV-like engine, preferably an intermediate control line or a replacement control line (br) is programmed as a control characteristic curve for favorable fuel consumption, which is used to compare the desired value with the engine control signal (k) serves and according to which the motor control signal (k) forms the corresponding control variable between the control device ( 5 ) and the drive motor (M), or
• b) in conjunction with a speed-controlled (RQV) or power-controlled (RQ) engine, each power size is assigned a low-consumption engine speed and the gear ratio control by comparing the target / actual value between the engine speed signal (b) and the engine control signal (k) is activated, the motor control signal (k) representing an automatic output variable of the electronic control device ( 5 ) for the drive motor (M).

46. Transmission according to one of claims 44 or 45, characterized in that a election device is provided, in which either PDO or PTO operation with the required constant engine speed or consumption-oriented operation (E-operation) can be selected, whereby a speed limit during PDO operation preselected constant engine speed within a certain Control range (delta s; delta sr) at full load and part load maintained and in normal or economic operation or E-circuit the engine speed at the vehicle speed Limit point variable at part load and preferred to one consumption-friendly characteristic curve or characteristic values is adaptable. 47. Transmission according to one or more of claims 1 to 46, characterized in that the Speed limitation functions by pressing the Brake pedals are interrupted or overridden or canceled be or that these functions by appropriate prefix saved and, if necessary, can be called up again. 48. Transmission according to one or more of claims 1 to 47  characterized in that the regular Characteristic curve (a; k) a constant or one of different Operating or / and variable dependent on driver characteristics Characteristic can be, this line of consumption oriented operating values or performance-oriented Operating values or a variable or gradually selectable or automatically adjustable (A1, A2, A3, A4) between one upper (A1) and a lower characteristic curve (A4) can be effective the corresponding setting signals are arbitrary preselectable or automatically depending on different Operating signals or actuation signals can. 49. Transmission according to one or more of claims 1 to 48, characterized in that a Motor control is provided, the optional one Power control or speed control allowed, whereby preferably when preselecting a consumption-oriented regulation the power control (RQ) and if a constant Speed operation, such as B. PTO operation at one Tractor, speed control (RQV) is activated. 50. Transmission according to one or more of the preambles of the claims, characterized in that the control and regulating device is designed so that the engine control works in the manner of an RQV control or constant speed control, each accelerator pedal position (accelerator pedal signal a) or more firmly Throttle setting (z. B. hand throttle) is assigned a certain engine speed (engine speed signal b), wherein an automatic driving or speed control is effective such that z. B. at a fixed gas setting with load-dependent speed depression by a predetermined difference size (s) automatically a translation reset, that is, a translation change in the direction of lower speed is effected, preferably a delay signal to avoid undesirable engine high-speed is effective, or that without fixed Throttle setting for normal driving operation accelerator pedal signal and engine speed signal are compared with each other, whereby after exceeding the engine speed signal (b) the gear pedal signal (a) triggers a gear ratio reset, with delay signals preventing undesired engine high speed ( Fig. 6i). 51. Transmission according to claim 50, characterized in that a Device for the continuous adjustment of a constant Engine speed and a stepless adjustment of a constant Speed is provided, when reaching the Motor power limit at this set Engine speed an automatic, adjusted speed reduction in accordance with the full load condition at the preselected The throttle is adjusted and the engine speed is pressed Signal for the corresponding translation reset triggered becomes. 52. Transmission, in particular according to claim 50 and 51, characterized in that the brake signal (f) by actuating the brake pedal ( 7 ) causes a translation reset of the transmission and that the starting control is designed so that only when the brake pedal ( 7 ) is depressed the first range clutch or starting clutch can be switched after the corresponding preselection via the selector lever ( 108 ) and that after releasing the brake, the starting process is initiated by removing the brake signal (f) ( Fig. 6i) that is operatively connected to the engine speed signal (b), or that a bypass valve ( 114 c) is actuated for the starting device, which connects the two working pressure lines of the hydrostatic units (A, B) to one another and switches off the bypass function via a control line ( 113 ) after releasing the brake. 53. Device according to one or more of the claims, characterized in that the Control device is designed so that after manual or automatic switch-off of the consumption-oriented program and after the acceleration phase, e.g. B. at one Overtaking process, automatically on the consumption-oriented  Driving program is switched, said switching with or without a time delay. 54. Transmission according to one or more of the claims, characterized in that the stepless control device is influenced by the adjustment accelerator pedal speed, through speed difference values, Front and / or rear wheels or / and from a signal of Centrifugal force behavior of the vehicle, for example when cornering drives, the adjustment speed of the stepless Translation change due to the aforementioned influencing factors in adapted dimensions with regard to driving comfort, driving safety, Mileage and / or fuel consumption adjusted accordingly or accelerated or decelerated. 55. Transmission according to one or more of claims 1 to 54, characterized in that the stepless transmission control from information or one or several of the signals from the ABS braking system is affected, so that depending on the operating situation, a targeted, continuous reduction the driving forces or the driving power to increase the Driving safety and also to improve driving comfort is achieved. 56. Transmission according to one or more of the claims, characterized in that the entire Overdrive area is divided into individual areas or is infinitely adjustable, with a small one for normal operation Overdrive area switched on and the large one in special operation Overdrive area manually or automatically depending on one or more signals, e.g. B. a time signal or / and Speed signal or by detection from continuous operation Behavior is switchable. 57. Transmission according to one of the preambles of the preceding claims, characterized in that a control and regulating device is provided which allows a smooth driving behavior in the lower speed range for winter operation, such that the working pressure of the hydrostatic transmission ( 4 c) by a pressure regulator or a bypass valve ( 114 c; 216 ) can be modulated automatically or manually, the corresponding control signal ( 113 ) resulting from one or more of the operating signals, speed signal (b) or / and transmission ratio signal and / or manual actuation signal or / and a difference -Signal from speed signal (b) and accelerator signal (a) or / and throttle valve position and / or from one or more information from the ABS system or elements of the ABS system. 58. Transmission according to one of the preambles of the claims, characterized in that in the control and regulating device or the electronics ( 5 ) the consumption and efficiency values of the engine (engine map) and transmission efficiency values (efficiency map) are stored and the electronics are the most economical and / or operating mode with the lowest pollutants and subsequently determines and automatically adjusts the corresponding gear ratio or engine speed. 59. Transmission according to claim 58, characterized in that one or several sensors are provided which provide information, after which the control and regulating device a correction of Gear ratio or / and the engine speed causes such that a reduction in pollutant emissions is achieved the key parameters being the consumption parameters of the Engine depending on the parameters - accelerator pedal position, Engine speed, air temperature, air pressure and others therefor suitable factors in their combination as a starting point for the serve control signal to be formed. 60. Transmission according to one or more of the preambles of the claims, characterized in that in the case of a drive combination with a continuously variable hydrostatic power split transmission (for example as shown in the embodiment according to FIG. 3), in which the hydrostat ( 4 c ) is set to the delivery volume, which, depending on the gearbox design, can correspond to the end point of the hydrostatic adjustment, when the engine is started, especially when cold, with the range clutches open or open (K1, K2; K3; K4), the hydrostatic set to zero or to a small delivery volume that the hydrostat ( 4 c) before the start of the relevant range clutch (K1) is issued after a signal to the start position, and that the signal for issuing the hydrostatic transmission to the start position is dependent on the oil temperature and / or in relation to the engine or Idling speed and / or depending for hydrostatic pressure or other operational influences is triggered automatically, after which the hydrostatic ( 4 c) is turned to the start position. 61. Transmission according to one or more of the preambles of the claims, characterized in that in the case of a drive combination with a continuously variable hydrostatic power split transmission (e.g. a transmission according to the embodiment according to FIG. 3), in which the hydrostat ( 4 c ) is set to the delivery volume, when the engine is started, especially in the cold state with the range clutches open (K1; K2; K3; K4), the hydrostat is set to zero or to a low delivery volume, whereby before the relevant range clutch (K1) is closed, the Hydrostat ( 4 c) is issued as a function of a predetermined engine speed signal to the starting position, the hydrostatic adjustment speed being regulated via the engine speed signal. 62. Transmission according to one of claims 60 and 61, characterized in that one for the Range switching clutch (KV; KR) and / or one Locking device (FH) to prevent uncontrolled Rotational movements of gear links before closing the corresponding area clutch (K1) closed before driving is. 63. Transmission according to one or more of claims 60 to 62, characterized in that a acoustic or / and optical signal is provided, according to Starting the engine is ready for operation after sufficient Oil temperature signals, preferably such that the above  Display signal until the oil temperature or / and Approach position of the hydrostatic is effective. 64. Transmission according to one or more of claims 1 to 63, characterized in that the hydrostatic brake system ( 201 ) is designed such that at least one of the brake valves, preferably the pressure control valve (brake control valve 204) on or in the hydrostatic transmission ( 4 c) is arranged or integrated, preferably the hydrostatic transmission ( 4 c) is noise and vibration damped, for. B. via a three-point bearing with elastic torque arm. 65. Transmission according to claim 64, characterized in that elastic or movable oil guide members between the hydrostatic transmission ( 4 c) and the transmission housing ( 3 ) as an oil guide within the transmission for the oil to the heat exchanger ( 205 ) and / or optionally to the energy store ( 220 ) to serve. 66. Transmission according to one or more of the preambles of the claims, characterized in that the hydrostatic brake system is designed such that the high-pressure limiting valve of the hydrostatic converter ( 4 c) is designed as a controllable pressure valve ( 217 ) and is preferably connected between the two working pressure lines, wherein the pressure control is influenced as a function of the oil temperature or a pressure signal and / or temperature signal and / and a hydrostatic adjustment signal and / or a load-dependent signal. 67. Transmission according to one or more of claims 1 to 66, characterized in that the brake control is designed so that the amount of brake oil or variable of the hydrotatic converter ( 4 c) is controlled via the oil temperature or a temperature signal. 68. Transmission according to one or more of claims 1 to 67, characterized in that a feed and flushing device ( 218 ) for the hydrostatic converter ( 4 c) is provided, which is designed such that the full amount of feed oil into the hydrostat -Oil circuit can be introduced and the feed pressure is determined by an adjustable pressure relief valve ( 235 ; 233 ) and that preferably the exit oil is used for the control pressure of the clutches and / or other consumers of the motor vehicle. 69. Transmission according to one or more of claims 1 to 68, characterized in that the feed and rinsing device ( 218 ) is designed so that feed and discharge openings at different, preferably outside the same flow line, points of the hydrostatic working Circulation, in particular the kidney-shaped recess ( 229 ) of the hydrostatic converter ( 4 c) are arranged in order to force the full inflow of the amount of cooking oil into the hydrostatic circuit. 70. Transmission according to one or more of claims 1 to 69, characterized in that the tax and Control device of the transmission is designed so that a Individual program depending on the driver type is programmable, this program being manually preselectable is, e.g. B. by pressing one with a name labeled push button or combined with one that automatic seat adjustment assigned to a specific person or / and steering wheel adjustment or other personal Settings. 71. Transmission according to one or more of claims 1 to 70, characterized in that a Automatic consumption and / or pollutant-friendly program or is optionally available, or that there is an eco program automatically adjusts the gas pedal Speed of movement or / and the accelerator pedal Movement characteristics or / and depending on one Speed profile or / and road or / and load profile. 72. Transmission according to one or more of claims 1 to 71, characterized in that to improve the shift quality for the range shifts of the hydrostatic converter with an automatically controllable and / or adjustable bypass valve arranged between high and low pressure line of the hydrostatic converter ( 114 c; 216 ; 214 ; 215 ; 218 ; 233 ) is provided, which automatically responds when switching back from one to the other switching range, in particular during braking and / or overrun operation, preferably when a defined by one or more operating signals when switching on the bypass function Differential pressure between the two working pressure lines ( 206 and 207 ) is effective. 73. Transmission according to one or more of claims 1 to 72, characterized in that between the two working pressure lines ( 206 and 207 ) of the hydrostatic converter ( 4 c) switched pressure or bypass valve ( 214 ; 215 ; 233 ; 217 ) simultaneously serves as a brake control valve for the hydrostatic retarder function. 74. Transmission according to one or more of claims 1 to 73, characterized in that a manual Actuatable device is provided, which is a stepless Changing the gear ratio while changing the Engine speed allows, e.g. B. for the preparation of engine and transmission for an overtaking, the actuation any direction, e.g. B. in the form of a push button on the steering wheel or elsewhere, is designed or via an accelerator pedal signal, e.g. B. by one or, if necessary, multiple times brief tap. 75. Transmission according to one or more of claims 1 to 74, characterized in that at Braking operation, especially when braking hard and too strong interaction between gear and brake, through a corresponding signal, e.g. B. Pressure signal in the hydrostatic system or / and engine speed signal, the relevant range clutch opens. 76. Transmission according to one or more of claims 1 to 75, characterized in that in braking operation the pressure valve or bypass pressure valve ( 114 c; 214 ; 215 ; 233 ; 216 ) in operative connection with the brake signal (f) and / or one Speed signal of the engine and / or a throttle valve position signal or fill signal of the engine and / and a transmission ratio signal and / or a synchronization signal is available. 77. Transmission according to one or more of claims 1 to 76, characterized in that the pressure valve or bypass pressure valve ( 114 c; 214 ; 215 ; 233 ; 216 ) comes into effect by a corresponding signal in braking operation, a minimum Differential pressure between the two working pressure lines ( 206 and 207 ) is maintained, in particular for the purpose that a translation adjustment can take place within the braking phase via the transmission control. 78. Transmission according to one or more of claims 1 to 77, characterized in that the service brake and transmission brake and / or hydrostatic retarder brake system are matched to one another in such a way that an interaction of the service brake and hydrostatic brake is avoided by using a bypass function the bypass pressure valve ( 114 c; 214 ; 215 ; 233 ; 216 ) a division of the respective brake components via the service and transmission brakes are dosed accordingly differently, different operating signals, such as brake pedal signal, speed signals, pressure signals, Switching and / or synchronous signals are brought into a corresponding operative connection. 79. Transmission according to one or more of claims 1 to 78, characterized in that when braking operation of the transmission-side braking component is such that with decreasing driving speed or vehicle deceleration Engine speed a speed reduction, preferably with continuous course, experiences.