KR19990082258A - How to improve shift characteristics during gear shift and gear shift control - Google Patents

Abstract

The present invention relates to a gearbox unit (1) comprising at least one gear branch for power transmission via a hydraulic clutch (2) that can be coupled in series with a mechanical gear portion comprising means for implementing at least two types of speeds. The present invention relates to a method for improving gear shift characteristics during gear shift. In the present invention, while the power transmission via the hydraulic clutch during the gear shift operation between the two mechanical speeds, the filling ratio of the hydraulic clutch (2) is changed to at least indirectly rotate the rotational speed of the main bucket wheel of the hydraulic clutch (2) The characterizing variable is characterized in that it is substantially constant in some range of gear shifting operation.

Description

How to improve shift characteristics during gear shift and gear shift control

Hydrodynamic-mechanical gearbox units are known in many embodiments as automatic transmission forms for use in vehicles. Automatic transmissions each include at least one gear branch. The gear branch comprises a hydraulic clutch and a mechanical transmission that can be arranged in line with the hydraulic clutch. The mechanical transmission includes rotational speed / torque converters with suitable gear ratios. The devices are driveable by appropriate control elements. At this time, various speeds are realized by driving or releasing the corresponding control elements in the mechanical transmission. Individual rotational speed / torque converters are preferably implemented in the form of spur gears or planetary gear tanks. To implement the gear shift it is necessary to drive or release the corresponding control element of the mechanical transmission. When shifting to a high gear within an automatic transmission, two stages are started, the so-called torque stage and the inertia stage. Before the high gear shift takes place, the torque input at the transmission clutch only includes the torque generated in the internal combustion engine and operating through the torque converter. During the torque transmission step, a predetermined pressure is applied to the clutch portion to be connected. This torque is distributed between the clutch to be released and the clutch portion to be connected. In the last stage of this torque the torque supported by the clutch to be released is reduced to " 0 " and the total torque is transmitted at the clutch to be connected. After the torque transmission is completed, the gear ratio transmission step, that is, the so-called inertia step begins. At this stage, the rotational speed of the internal combustion engine is quickly reduced to the new gear ratio dimension. This occurs to the extent that the pressure of the clutch to be connected increases. This generates a large moment of inertia, i.e. a large moment of inertia that must be absorbed in the clutch portion in addition to the torque generated by the internal combustion engine. This inertial torque generates a torque external force that is continuously transmitted internally or to the vehicle. A number of methods are known for reducing this torque external force. One of them is published in DE 691 13 193 T2. According to the disclosure, the control of the shift stage is achieved by constantly monitoring the input speed to the transmission input shaft and comparing the change at the end of the torque stage with a predetermined stored dimension. As a preferred method, there is also a method of improving the above-described control method by delaying the ignition timing of the motor by a predetermined time. An adaptive control system is provided for controlling the pressure in the torque generating device through friction of drive heat, the system comprising one combustion motor and one multistage gear. The system also has a torque input shaft provided between the internal combustion engine and the transmission and an initial friction mechanism at least partially securing at least a first transmission path on the drive shaft and the transmission input main part. There is a second friction mechanism for transmitting torque between the drive shaft and the second portion of the transmission. The system also includes first and second servo devices that are pressure driven. The servo drive always drives the first and second friction machines when set below pressure so that the formation of the second transmission path of torque is at a predetermined reduced motor speed. A device for continuously monitoring the speed at the torque input shaft, i.e. the transmission input shaft, and for increasing the pressure of the second servo device in response to a command to change the gear ratio requiring the operation of the first and second friction mechanisms. The device is provided. The system also includes a device for reducing a predetermined pressure in the servo device in response to a change in the rotational speed of the predetermined sensed torque input shaft, wherein the system results in a reduction in the clutch capability of the first friction mechanism during the shifting step. It includes a device for increasing the pressure of the servo device. The disadvantage of this control method is that the cost is very expensive since the adaptation to the pressure progression has to be carried out very sensitively. The application of the pressure dimension is also opposite to that in the transmission input shaft, in particular depending on the rotational speed of the transmission input shaft. Therefore, the change in the rotational speed or the inertia mass moment of the internal combustion engine again affects the application of pressure progression.

The present invention relates to a method for improving the shifting characteristic when shifting from one gear to a second gear, in particular when shifting from a high gear, to a method including the gist of the preamble of claim 1 and furthermore to a gear shift. It relates to a control method.

The present invention therefore aims to eliminate the drawbacks mentioned above by developing a method for controlling gear shifting in a hydrodynamic-mechanical gearbox. In particular, there is no moment distortion during the shift due to the rotational speed change or the mass moment of inertia of the internal combustion engine, so that the convenience in shifting is improved. The cost of design and control technology should be kept as low as possible.

The solution according to the invention is as characterized in the summary of claims 1 and 7. Preferred configurations according to the invention are given in the dependent claims.

The present invention relates to a method of gear shifting, i.e. a method of improving shifting characteristics during a change of two speeds in a transmission, comprising means for implementing at least two speeds and powered by a hydraulic clutch that can be connected in line with one mechanical transmission. In a transmission including at least one transmission branch for transmitting a gear shift, that is, a method of improving the shift characteristic when shifting between two speeds. In the hydrodynamic-mechanical power transmission transmission branch, when power is transmitted using the hydraulic clutch when a shift operation between two mechanical speeds is carried out, a variable which at least indirectly characterizes the rotational speed of the pump wheel of the hydraulic clutch is characterized by The charge ratio of the hydraulic clutch is monitored and adjusted in a manner that remains substantially constant over a certain range. As a result, at the beginning of the shift operation, the control of the rotational speed of the pump wheel starts through proper filling control in the hydraulic clutch, whereby the speed step is maintained before the shift. The rotation speed set and firmly defined for each shift operation is set as a comparison value or a set value.

The method according to the invention is carried out as follows: for example during pull-upshifting, in other words when shifting from the first low gear to the second high gear, the shift between the respective speeds is generally primary. By lowering the rotational speed of the bucket wheel and the components connectable thereto, in particular of the drive motor shaft. By adjusting the rotational speed of the pump wheel to a substantially constant value, the hydraulic clutch is flexible and can only allow a slip that is normally occurring in the hydraulic clutch. This results in no change in the rotational speed of the transmission input shaft or the drive motor connectable with the input shaft when the rotational speed / torque ratio of the power transmission and / or mechanical drive gear is changed during the shifting process. The shifting operation can be actively performed without a large pressure structure. Slip reduction is achieved by forcing the hydraulic clutch to harden by changing the vehicle speed or increasing the charge while taking into account the minimum allowable motor speed. The time interval of the adjustment process is preferably set to a predetermined band from the beginning of the shift process until reaching the synchronous rotational speed. However, it may be displaced chronologically by temporarily starting the shifting process and / or ending when a predetermined slip value, ie when the hydraulic clutch reaches a predetermined difference value between the primary bucket wheel and the secondary bucket wheel. Once the adjustment process has been completed, the slip is reduced to a minimum so that the slip values present in conventional hydrodynamic power transfers are recorded between two and three percent. The drive motor is again more accelerated and the hydraulic clutch can be operated with high efficiency.

The solution according to the invention is generally suitable for use in all gear shifting stages in a transmission that is not equipped with warp wings and is responsible for power transmission.

The solution according to the invention in a clutch equipped with an inclined vane arrangement is above all available for improving the characteristics of the shift in pull-up shifting. On the other hand, such adjustments are generally unnecessary at the time of push-up shifting or at pull-reverse shifting and push-reverse gear shifting. In a hydraulic transmission equipped with an inclined vane arrangement, that is to say in a charged hydraulic clutch, the primary bucket wheel of the hydraulic clutch is not released along the transmission input shaft and its associated drive motor. In this case, the hydraulic clutch is operated in a winsing force manner via the transmission output side in driving the secondary bucket wheel. The vehicle stops supplying gas and can roll strongly without brakes. In other words, no load change shock occurs, and when the drive motor moves at an increased idling speed, the operating method of the hydrodynamic component corresponds to a predetermined hydrodynamic rotation speed / torque converter component. The push-up shift has no influence on the drive motor connectable with the transmission input shaft, and thus hardly detects a problem.

In traction operation the drive motor is typically supported on the secondary bucket wheel during power transfer in a hydrodynamic-mechanical power transfer branch. This applies to the reverse gear shifting while the rotational speed of the secondary bucket wheel is increased. The motor speed cannot be increased by the selected gear. The hydraulic clutch again operates in a centrifugal force, whereby the mass of the motor has no negative effect on the shifting process.

Similar to the above push-up shift may be applied to the push-reverse gear shift on a transmission arrangement including a hydraulic clutch equipped with a tilting wing arrangement. In this case, the rotational speed of the drive motor is not affected by the gear shifting process.

The solution according to the invention has the advantage that the drive motor can be driven with a lower motor rotation speed because the output of the drive motor is adapted to the required running performance. Overall operating efficiency is maintained under driving conditions. Since the slippage is compensated for by the hydraulic clutch during gear shifting, the individual shifting elements required to achieve the respective speeds are less capable. Since the moment distortion due to the rotational speed change or the inertia mass moment does not occur in the gear shifting process in the drive motor connected to the transmission, the gear shifting process described above shows an increased convenience in shifting and is almost smooth. Since the drive motor is not changed in terms of its rotational speed at the time of shifting, the shifting rotational speed can be selected very small. When the hydraulic clutch is shifted, the rotational speed of the drive motor is constant.

The device constitutes a toroidal operating space and can be operated by a hydraulic clutch, comprising: a first hydrodynamic transmission comprising at least one primary and secondary bucket wheel; and means for implementing at least two different speeds. It consists of a gear box unit having a second mechanical transmission including one control or regulating device. The control or regulating device comprises at least two inputs and one output for implementing the driving scheme according to the invention. The first input is connected to a device for measuring and setting a signal indicative of the shifting process, while the second input measures at least one value at least indirectly characterizing the average rotational speed of the primary bucket wheel of the hydraulic clutch. Can be connected with the device. The value indicative of at least indirectly the average rotational speed of the hydraulic clutch of the primary bucket wheel is compared with a setting value corresponding to a value recognizable at the beginning of the shift or indirectly characterized by the rotational speed of the primary bucket wheel. do. According to the deviation between the set value and the actual value, a variable Y is configured which serves to trigger the device for changing the degree of fill of the hydraulic clutch. The change of the hydraulic clutch filling degree is again performed through a control or adjusting device. The control or regulating device is subordinate to the rotational speed control of the primary bucket wheel.

Options for adjusting the filling degree are as follows.

a) the degree of filling control within the speed control category or

b) Charge control in the charge control category belonging to the lower speed control.

For control of rotational speed, see "Voice-Fluid Engineering in Drive Technology", Krauskov Engineering Digest, 1987, "Control and Control Systems" ("Voith-Hydronamic in der Antriebtechnik", Krauskopf Ingenier Digest, 1987, Kapitel "Steuer- und Regelungen" is disclosed in the embodiments therefor. The above publication is fully disclosed in the disclosure of the present application. However, the adjustment of the filling ratio to the implementation of the rotational speed adjustment operation is not limited to the specific embodiment, and the decisive fact is that only a value at least indirectly characterizing the rotational speed of the pump wheel is set to a predetermined value in the initial speed step, This value is kept constant.

The transmission also has excellent operating efficiency over the entire area and is not disadvantageous compared to conventional transmissions in terms of shifting convenience and driving characteristics. Under the operating conditions "run", the hydraulic clutch member is operated at the highest state of charge, and there is almost no slip at this time, thereby achieving very excellent operating efficiency. At this time, the operating efficiency according to the load and rotational speed corresponds to 90 to 99%. This value is not available from any hydraulic transducer. The hydrodynamic component, ie the hydrodynamic component acting as a clutch in the starting phase, is tightly connected. In addition, the hydrodynamic component has all the advantages of fluid power transmission elements such as vibration dampening and noise reduction. When the slippage of the hydrodynamic component is increased in all subsequent shifting steps, the shifting motion becomes more flexible, at least reaching the dimensions of the slippage of the hydrodynamic transducer. In the first driving stage, the shift of the individual speed is made faster. As the unavoidable slip is transferred into the hydrodynamic component, the slip is again reduced by increasing the degree of filling. This allows for individual speeds, simultaneous load reduction, and more flexible transitions.

The slippage of the hydrodynamic components can also increase in a short time in the event of sudden load changes. Thus a fluidly flexible connection is achieved. In addition, there is little support during the push operation. The load change shocks that have previously been a concern are no longer a problem. In addition, the characteristic curve of the elastic shock absorbing member used has more improved characteristics when the load changes. The hydrodynamic component bridges during the "run" -drive phase if it does not harm the comfort of the shift in shifting between the individual gears. The above-described functions are guaranteed through control operations suitable for charging and discharging processes.

The hydraulic clutch can also fulfill other purposes, as an example of which the hydraulic clutch can also be used as a retarder in braking operation.

The method according to the invention will now be described with reference to the drawings.

1 schematically shows an axial sectional view of the transmission unit 1 shown, for example. The transmission unit comprises a first fluid transmission 2 in the form of a hydraulic clutch and a second mechanical transmission 3 which is operated according to the operating mode of the method of the present invention. The first fluid transmission 2 comprises at least two bucket wheels—a first bucket wheel and a second bucket wheel. The first bucket wheel is then shown as primary bucket wheel PR4 and the second bucket wheel as secondary bucket wheel SR5. The primary bucket wheel 4 and the secondary bucket wheel 5 form at least one toroidal working space 6 with each other. The operating space may be charged with the operating medium. For this purpose, the toroidal operating space 6 is provided with one drive medium supply unit, which is not shown in detail here. The gearbox unit 1 may be connected in series from the transmission input shaft E to the transmission output shaft A when the hydraulic transmission part 2 and the mechanical transmission part 3 are viewed from the power transmission surface. A possible connection method for connecting the hydraulic transmission unit 2 and the mechanical transmission unit 3 in series for power transmission between the transmission input shaft E and the transmission output shaft A is the transmission input shaft E and the transmission output shaft A. One gear branch for power transmission between At this time, another second gear branch is formed to transmit power to the transmission output shaft A away from the transmission input shaft E while the hydraulic transmission unit 2 is bypassed. Regarding the above method, the following description will be given of a driving method which mechanically enables power transmission between the transmission input shaft and the transmission output shaft, that is, from the first gear branch to the mechanical transmission 3 via the hydraulic clutch 2. I will. The structural embodiment of the transmission unit described for example is as follows: The secondary bucket wheel 5 is permanently connected to the mechanical transmission 3 by means of a connecting shaft 7. The connecting shaft 7 is connectable to the transmission input shaft E by means of so-called thorugh coupling, ie through coupling, also referred to as bridging coupling UK. By this connection, the secondary bucket wheel 5 can also be connected to the transmission input shaft E. FIG. The primary bucket wheel 4 is connectable to the transmission input shaft E via a so-called primary bucket wheel coupling PK. The primary bucket wheel 4 is installed on the connecting shaft 8, which is connectable to the transmission input shaft E and the primary bucket wheel coupling PK. In this case, a braking member, which can be described as the primary bucket wheel brake PB, is provided on the connecting shaft 8. The primary bucket wheel brake PB is securely fixed to the gearbox 9 as shown, preferably at a stationary transmission.

The secondary bucket wheel 5 is connectable to the second machine transmission 3 by means of a connecting shaft 7. The second mechanical transmission part 3 includes three planetary gear units, namely a first planetary gear group PRI, a second planetary gear group PRII, and a third planetary gear group PRIII in the case shown. The individual planetary gear tanks each include at least one first sun gear—Ia in the first planetary gear unit (PRI), IIa in the second planetary gear group (PRII), IIIa— in the third planetary gear group (PRIII), and one ring. Gears, planetary gears, and fixed links. The ring gears of the individual planetary gear units are shown here as Ib for the first planetary gear device PRI, IIb for the second planetary gear device PRII, and IIIb for the third planetary gear device. When using such a transmission unit, for example, six speeds may be realized in the driving mode. At this time, the bridge coupling does not operate at at least two speeds. In the first gear of the first operating step, the primary bucket wheel coupling PK is driven in the so-called start gear, whereby the transmission input shaft E is connected to the primary bucket wheel 4 by the connecting shaft 8. Connected. The connection between the hydraulic transmission part 2 and the mechanical transmission part 3 is realized by a first coupling member K1. The second and third braking members B2 and B3 are also operated. The fluid constituent unit 2, in particular the toroidal operating space 6, is filled with a working medium at this stage. The flow of energy, or power, is transmitted here via a drive motor and transmission input shaft (E), primary bucket wheel coupling (PK), primary bucket wheel (4), secondary bucket wheel (5), not shown here. Indirectly coupled to the fixed link (IIId) of the third planetary gear group via the secondary bucket wheel (5) through the member (K1), the first planetary gear group (PRI), in particular through the ring gear (Ib) of the first planetary gear group It is thereby indirectly connected to the transmission output side A, for example a unit driven like a wheel of a vehicle.

The hydraulic transmission portion 2 operates as a hydraulic clutch in the starting process. When switching to the second gear, the third braking member B3 together with the first clutch member K1 is in an operating state. It also works like the primary bucket wheel coupling PK. The second braking member B2 is released and the first braking member B1 is operated. Since the bridge coupling UK does not operate at least in the second gear, the hydraulic transmission member 2 is responsible for the function of the hydraulic clutch in the second gear. The bridge coupling UK also does not work in the third gear. However, the primary clutch wheel coupling PK, the first clutch member K1, and the second clutch member K2 and the third braking member K3 operate. All other load change members are not engaged. Energy flows through the transmission input shaft (E) to the first planetary gear tank (PRI) via the hydraulic transmission unit (2), the connecting shaft (7), and the first clutch member (K1), in particular the first planetary gear tank ( PRI) ring gear (Ib). The other tributary of the power is transmitted to the sun gear Ia of the first planetary gear tank PRI via the second clutch member K2. In addition, the power feeders combined with the fixed link Id of the first planetary gear group PRI are transmitted to the transmission output shaft A via the fixed link IIId of the third planetary gear group PRIII.

In the fourth gear, the first clutch member K1, the third clutch member K3, the bridge coupling UK, the primary bucket wheel coupling PK, and the secondary braking member B2 are driven. All other load changing members are in an unengaged state. By means of the second braking member B2 a fixed link IId of the second planetary gear set PRII is constructed. The ring gear IIId of the third planetary gear group PRIII is connected to the fixed link of the third planetary gear group IIId. The power transmission is via the bridge input (UK) by the transmission input shaft (E), through the connecting shaft (7), the first clutch member (K1) to the ring gear (Ib) of the first planetary gear group (PRI), Planetary gears IIIc of the third planetary gear group PRIII connected to the ring gear IIIb for driving the fixed link of the third planetary gear group PRIII via the second planetary gear group PRII and the connecting shaft 10. To the transmission output shaft A.

In the fifth gear, only the second braking member B2 is released and the first braking member B1 is driven, which is between the first planetary gear group PRI and the second planetary gear group PRII, in particular the This means that the connection between the connecting shafts 11 is established. The sun gears Ia and IIa of the two planetary gear tanks (PRI and PRII) are also stationary. The power transmission again passes through the input shaft E, the bridge coupling UK, the connecting shaft 7, the first clutch member K1, and the ring gear Ib of the first planetary gear group PRI. By the fixed link Id of PRI, it is performed in order of the transmission output shaft A via the fixed link IId of the 3rd planetary gear group PRIII.

The sixth gear is different from the fifth gear in that all the clutch members K1, K2, K3 are driven and the braking members are in a released state.

The shift characteristic at the time of changing the speed to the next speed actually depends on the driving of the individual control members K1 to K3 and B1 to B3 in the mechanical transmission. In particular, the magnitude of the driving force is important as well as the continuous operation of driving the "coming control element" and releasing of the so-called "leaving control element". "Coming control member" is a control member or element that meshes between two different gears, ie, the control member driven in the next gear selected upon gear change. The "thin control materials" are control materials that are engaged with the previous speed or are released when the gear is shifted even at the desired gear shift.

FIG. 2 shows the rotational speed / torque flow in relation to the drawings schematically illustrated by way of example in various diagrams. The traveling curve is for the transmission described in FIG. 1 and can be used in the environment without following the method according to the invention. There are correlations between the pressures over time that are individually set to the control material. These correlations tell the relationship between the adjusted torque change and the rotational speed change of the drive side, that is to say the transmission input shaft and the output side. From the above correlation, it can be seen that a large amount of torque distortion occurs in the band (I). This phenomenon can be reduced by adapting the pressure corresponding to the coming and / or fine control material according to the prior art accordingly.

In order to solve the above object of the present invention and to eliminate the above-mentioned disadvantages of the prior art, the gearbox unit 1 of the present invention is provided with a control device or an adjusting device 15. The devices comprise at least two inputs, namely a first input 16 and a second input 17 and a first output 18. The control and adjustment device 15 is responsible for compensating for the slip generated in the mechanical transmission 3 during gear shifting. This may be regarded as related to the slippage between the respective clutch member portions or brake member portions. These members are all connected to the drive side or the driven gear side and are interconnected for torque transfer. In this case, it can be seen that the driving side is the gearbox unit 1 region. Within this region it is shown that power transmission during the traction operation is carried out from the transmission input shaft to the first member of the control member "coming" upon gear shifting in the direction of the transmission output shaft. The second member of the " coming " control member connected at least indirectly to the transmission output shaft A is on the output side. Particularly in a drive that is connectable to the transmission input shaft E and to the input shaft when shifting from the first gear to the next gear, for example from the first gear to the second gear during a full-shift operation. For example, a decrease in the rotational speed of the internal combustion engine begins. This reduction in rotation speed is compensated by the hydraulic clutch 2 in the present invention. However, this only applies to the gear shifting movement from the low gear of the first stage to the high gear of the second stage. Power transmission during this speed increase movement is at least partly achieved by the hydraulic clutch 2. Slip compensation is performed by changing the filling ratio in the operating space (6) of the hydraulic clutch. The practical purpose of the charge ratio change is to achieve a substantially constant rotational speed of the drive motor connectable with the transmission unit 1 at least indirectly with the rotational speed of the pump wheel 4. The hydraulic clutch 2 is also used for rotational speed control. The charge ratio change is made at the time of adjustment belonging to the control and / or rotation speed control itself. In order to change the rotational speed control, an actual value of a value at least indirectly showing the rotational speed of the primary bucket wheel 4 of the hydraulic clutch 2 is recognized and the actual value is determined by the control or regulating device 15. It is input by 1 input. The first input 17 is at least indirectly connectable with a predetermined device for recognizing the value seen at the rotational speed of the pump wheel 4. Since the rotation speed control operation according to the method of the present invention takes the role of a slip compensation during gear shifting, the second input 16 of the control or regulating device 15 receives a signal indicating that the gear shifting (SW) is in progress. It is connected to a predetermined device for setting and / or recognizing. In this case, the rotation speed of the transmission input shaft E is examined as a value used to indicate the rotation speed of the pump wheel. The actual value N _EIST is a value taken by the control or regulating device 15 in comparison with the set value n _SOLL . Here, the set value n _SOLL is a preset value set in order to display a value which may be indirectly characterized by the rotational speed of the pump wheel 4, and a value and / or use firmly defined for different driving conditions. Possible setting. In the case mentioned at the end, the set value is for example the transmission input shaft E and / or the hydraulic clutch 2 pump wheel when the shifting process has been started or when a signal for a desired desired gear shifting process has been input. It is used as a value that characterizes the rotational speed or the rotational speed input to the pump wheel shaft (8). The comparison operation is carried out in the comparator 19, where at least it is determined that the difference between the set value and the actual value is "0" or not equal to "0" in view of the two cases. Only in the case mentioned at the end, the correction to the output 18 is output to the control or regulating device 15. The correction value is effective at least indirectly for the device for influencing the filling ratio inside the operating space 6 of the hydraulic clutch 2. This device is indicated here by reference numeral 20 and serves as a so-called actuator.

Each possible method for adjusting the filling ratio is as follows.

a) filling rate adjustment within the rotational speed control range or

b) Filling ratio adjustment within the filling ratio control range belonging to the lower speed control

Details on the performance of rotational speed control can be found in "Voice-Fluid Engineering in Drive Technology", Krauskov Engineering Digest, 1997, "Control- and Control Systems" ("Voith-Hydronamic in der Antriebtechnik", Krauskopf Ingenier Digest, 1987, Kapitel Examples are disclosed in "Steuer- und Regelungen". The above publication is fully disclosed in the disclosure of the present application. However, the adjustment of the filling ratio to the implementation of the rotational speed adjustment operation is not limited to the specific embodiment, and the decisive fact is that only a value at least indirectly characterizing the rotational speed of the pump wheel is set to a predetermined value in the initial speed step, This value is kept constant. Embodiments of the transmission unit corresponding to FIG. 1 will only be described with respect to the implementation variants.

The control or regulating device 15, which serves to implement the filling ratio change, is also configurable so that a separate member, in particular a shifting member, is triggered in the mechanical transmission 3. It is preferred to make the control or regulating device 15 a component of the higher control or regulation system. In particular, when the device is used in an upper control or regulation system of the vehicle, it plays a role of triggering different components in the central travel control device, that is, the drive train.

According to each input value to the control or adjustment device 15, it is preferable to start the shifting process and to adjust the rotational speed of the gear and to control the filling ratio of the hydraulic clutch. At this time, the speed level existing before the shift should be maintained. The speed change is generally performed at a low rotational speed of a pump wheel and a motor connectable to the transmission input shaft. However, by using the control method, the hydraulic clutch becomes flexible and can generate only the slip required in the hydraulic clutch. Individually, for example, pull-upshifting is carried out in the direction of lowering the charging ratio for slip reduction or compensation. The charge ratio change is determined through the slip value in the above manner.

3 shows the correlation between the filling ratio and the slip. This may also be referred to as the rotational speed ratio relationship between the pump wheel and the turbine wheel or the primary bucket wheel and the secondary bucket wheel of the hydraulic clutch. This shifting process does not cause any change in the motor rotation speed. Speed shifts are active without much pressure buildup. Slip reduction utilizes a method of forcibly hardening the hydraulic clutch in consideration of vehicle speed or minimum allowable motor rotational speed. When the slip is reduced to the minimum size, the rotational speed control becomes inoperable and the drive motor connectable with the transmission input shaft E can be further accelerated. In other words, the hydraulic clutch is again operated at maximum efficiency.

The method according to the invention is of primary importance mainly in the implementation of pull-up shifts because of the hydraulic clutch with inclined vanes in the machine-hydrodynamic hybrid transmission. In a push or pull-reverse gear shift, such a scheme typically does not require the characteristics of this type of hydraulic clutch. Separately, the solution according to the present invention in a clutch having a wing arrangement without inclination may be considered important in all shifting processes.

4 is a schematic diagram of a motor output versus acceleration diagrammatically. The dashed line shows the behavior in a conventional transmission unit with a hydraulic clutch and a mechanical transmission. The area I indicated by hatching indicates the operation of the hydraulic clutch using the hydrodynamic transmission member, that is, charging and power transmission operation, as an operating region. The dashed line represents the characteristic curve of the transmission unit as adjusted in the method constructed in accordance with the invention. This makes it clear that the hydraulic clutch operates at a constant rotational speed while being driven and the difference between the two characteristic curves represents the amount of efficiency loss, which can be adjusted when using the method according to the invention.

The figure shows the configuration of a transmission in which the hydraulic clutch is responsible for power transmission in one and two gears. However, other embodiments are conceivable as well.

The solution according to the invention can be used for a transmission unit having one hydrodynamic transmission and one mechanical transmission. Here, the hydrodynamic transmission portion is composed of a hydraulic clutch and can be used to shift the gear from the desired first gear to the other two gear when shifting the gear through the hydraulic clutch during power transmission. In this case, there are other purposes on the individual transmission parts, ie the hydrodynamic rita as well as the function of the hydraulic clutch, as not specifically described in German patent publication 297 00 605 in the hydrodynamic transmission. It doesn't matter whether or not Arthur is a function.

Claims (11)

A shifting characteristic during gear shifting in one gearbox unit comprising means for implementing at least two speeds and comprising at least one gear branch for transmitting power by a hydraulic clutch connectable in series with the mechanical transmission. In a method for improvement, While power is transmitted using the hydraulic clutch when a shift operation is performed between two mechanical speeds, the filling ratio of the hydraulic clutch is at least indirectly a variable that characterizes the rotational speed of the primary bucket wheel of the hydraulic clutch. A shift characteristic improvement method, characterized in that it is changed in a manner that remains substantially constant over a certain range. The method of claim 1, wherein the range at which the variable characteristic of the rotational speed of the primary bucket wheel is maintained at least indirectly can be represented by a time interval between when the shift operation is started and when the synchronous rotational speed is reached. The shift characteristic improvement method. The method according to claim 1, wherein the range in which the variable which at least indirectly characterizes the rotational speed of the primary bucket wheel is kept constant can be represented by the time interval between the start of the shifting process and the time before reaching the synchronous rotational speed. The shift characteristic improvement method characterized in that. 2. The method of claim 1, wherein the control of the variable indicative of the rotational speed of the primary bucket wheel is at least indirectly taken when there is a slip. 5. Method according to any one of the preceding claims, characterized in that the filling ratio used to adjust at least indirectly a parameter representing the rotational speed of the primary bucket wheel is controlled. 6. A method according to any one of the preceding claims, wherein the filling ratio used to control a variable indicative of the rotational speed of the primary bucket wheel is adjusted at least indirectly. A mechanical transmission having at least one hydraulic transmission comprising a hydraulic clutch and at least one gear branch for transmitting power by a hydraulic clutch having means for implementing at least two speeds and connectable in series with the mechanical transmission. In the control for the improvement of the transmission characteristics in a hydrodynamic-mechanical hybrid transmission having a portion, And a means for controlling the rotational speed of the pump bucket wheel of the hydraulic clutch during the gear shifting operation. The method of claim 7, wherein The means comprising a control device having a control device having at least one first input and at least one second input and one output; The first input is connectable with a signal measuring device for gear shifting; The second input is connectable with a signal that determines or provides at least one variable indicative of at least indirectly the rotational speed of the pump bucket wheel; The output is connectable with one device for influencing the filling ratio of the hydraulic clutch; And at least indirectly comparing an actual value of a variable representing the rotational speed of the primary bucket wheel with a set value and outputting an adjustment value if there is a deviation. 9. The control method according to claim 8, wherein the apparatus includes a control element for matching the supply to the operating space of the hydraulic clutch when the discharge opening of the hydraulic clutch is constant. 9. The control method according to claim 8, wherein the device comprises a control element for driving medium to remove working fluid from the actuating circuit of the hydraulic clutch. 11. The apparatus of any one of claims 8 to 10, wherein the device comprises one control device whose input value represents at least indirectly the charge ratio change and the output value is a set value for triggering the actuator of the hydraulic clutch. The control method, characterized in that.