DE102007002166A1 - Hydrodynamic driving device operation method for drive train of e.g. car, involves partly carrying fluid for filling hydraulic circuit of driving device from storage device during presence of requirement for starting engine - Google Patents

Abstract

The method involves holding a limiting device and/or a housing device in a direction of their operating condition equivalent to minimum of volume of a storage area by a holding device. Hydraulic fluid stored in a storage device (9) is partly carried for filling a hydraulic circuit of a hydrodynamic driving device (5) from the storage device during presence of a requirement for starting an internal-combustion engine (3) e.g. petrol engine.

Description

The The invention relates to a method for operating a hydrodynamic Starting device of a drive train of a vehicle according to the Preamble of claim 1 further defined type.

Out the practice known vehicles, which with gasoline or diesel fuel engines are executed, are for consumption and pollutant emission reduction executed with different vehicle concepts, by means of in suitable operating conditions of the vehicles whose Internal combustion engines are at least temporarily switched off. Such systems are referred to inter alia as engine-start-automatic systems, the most diverse depending on operating conditions Vehicle components are activated or deactivated and even at short vehicle stoppages an internal combustion engine one Switch off vehicle and if there is a request for connection start the combustion engine again.

Around an impairment of a conventional driving operation by avoiding an engine start-up automatic system is at a Driver side requested continuation of the vehicle, in particular when entering heavily used and rightful roads, a short start of the engine and an immediate Traction structure required in a transmission of the vehicle. In known automatic transmissions or automated manual transmissions, trained with wet-running multi-plate clutches and brakes are executed hydraulically controllable switching elements, the switching elements are essentially via a gear pump only with the internal combustion engine running with the required control pressure provided. When traction in the gearbox is initially to overcome an air play the switching switching elements and then the switching switching elements by raising the control pressure according to predetermined Completely close the connection characteristics. Of the Compensation of the air gap of a hydraulically controllable switching element and their connection in the power flow of a transmission device is achieved by guiding a certain hydraulic fluid volume flow in a piston chamber of a hydraulically controllable and zuschaltenden Switching element achieved by the driven by the started combustion engine Gear pump is to provide.

are before a restart of the vehicle due to the disconnected Internal combustion engine several switching elements of a transmission device open and to close for the return of the vehicle, the time between the start of the startup process is extended the engine and the time at which the adhesion is completely made in the transmission device, possibly such that one with an engine start-up system executed vehicle not in a desired extent can be operated.

Of Furthermore, powershift transmissions are used for starting assistance preferably with hydrodynamic starting devices, such as hydrodynamic torque converters, Föttinger couplings or the like formed. The empty hydraulic circuits of such starting devices However, when the engine is switched off over the Time to about half the filling volume. This emptying process Although by sealing elements, such as rectangular rings, or equivalent Delayed valve devices, however, is the emptying process only with undesirably high costs reducible and basically not completely avoidable.

there is an emptying process of a hydrodynamic starting device in addition to the service life of the hydraulic fluid temperature in the hydraulic Circuit of a starting device at the time of switching off and to Switch-on time of the internal combustion engine and also of Abdichtverhältnissen Be rich in a hydrodynamic starting device with hydraulic fluid supplying hydraulic lines dependent. Based on these varied influencing parameters is a degree of filling a hydraulic circuit of a hydrodynamic starting device only with high measuring effort or by parameterized calculation models estimated. However, such estimates are only conditionally suitable the current transmission capability to determine a hydrodynamic starting device.

Lies a hydrodynamic starting device at the start time of a Internal combustion engine or during commissioning of a vehicle in a partially filled state an output torque at the output of the vehicle compared to a completely filled hydrodynamic starting device delays with a shallow gradient. With increasing Operating time is the hydrodynamic starting device by a assigned hydraulic system sufficiently filled and points then the desired transmission capability on. The reliable construction of the transmission capability in the area of a hydrodynamic starting device is necessary for vehicles for a high level of comfort and for safety reasons operate in a specified manner.

The hydraulic pump device of a hydraulic system or a transmission main pump driven by the internal combustion engine of a hydraulic system of a Getriebeein Direction is usually carried out for economic reasons with a capacity that is insufficient for a sufficient filling of a hydrodynamic starting device within a few seconds.

In order to Vehicles with conventionally designed transmission devices as well as with hydrodynamic starting devices and implemented Motor start-automatic systems still in the desired Way are operable, are known vehicles in addition a transmission main pump with another electric motor operated Hydraulic pump formed whose volume of the Speed of the internal combustion engine is independent and the in the absence of pressure supply via the transmission main pump the transmission device in the hydraulic system at least one pressure generated by means of which the air play of each for the production of Traction in the transmission zuzuschaltenden switching elements compensated is and / or a sufficient filling of a hydrodynamic Starting device is feasible.

In others, for example, from the DE 10 2006 014 756.1 and the DE 10 2006 026 980.2 Known vehicle systems, the gear means each instead of another electric motor operated hydraulic pump so-called devices for storing hydraulic fluid of a hydraulic system of a transmission device of a vehicle with at least one limited by a housing device and a limiting device and can be brought into operative connection with a hydraulic system of a transmission device for the exchange of hydraulic fluid storage space, the volume of which is variable between a minimum and a maximum depending on an operating state of the limiting device and / or the housing device.

The Limiting device and / or the housing device be from a valve device and / or a holding device at least in the maximum of the volume of the storage space equivalent Operating state against a Rückstellbestrebens the Housing device and / or the limiting device starting from one of the minimum of the volume of the storage space equivalent Operating state different operating state in the direction of Minimum of volume storage space equivalent operating state held.

In order to is a for controlling switching elements of a transmission device provided defined hydraulic fluid volume in the storage space cacheable and operating state dependent by valve device side or holder-side release of the limiting device and / or the housing device due to the Rückstellbestrebens the housing device and / or the limiting device in the hydraulic system of a transmission device with a defined pressure introduced.

By the one additional memory of a hydraulic system of a transmission device constituting device for storing hydraulic fluid in a simple way the possibility of one of a kind Internal combustion engine of a vehicle driven hydraulic transmission pump during a starting process of the internal combustion engine to the effect to assist that hydraulic system during a startup process of the internal combustion engine a total of a hydraulic fluid volume is fed, which for a positive connection in the field of transmission device within a predefined Joining time is required.

Of the present invention, the object is a method for operating a hydrodynamic starting device of a drive train a vehicle with one with hydraulically operated Switching elements running gear device with a preferably operable via an engine-start-automatic system Internal combustion engine and with a memory device to the memory to provide hydraulic fluid, by means of which a hydrodynamic starting device during a starting process an internal combustion engine having a transmission capability can be displayed within short control times.

According to the invention this task with a method according to the features of claim 1.

In the method according to the invention for operating a hydrodynamic starting device of a drive train of a vehicle having a preferably with hydraulically actuated shift elements transmission device, preferably with an engine start-automatic system operable internal combustion engine and with a memory device for storing hydraulic fluid, with at least one formed by a housing means and a limiting means limited storage space whose volume is variable depending on an operating condition of the limiting means and / or the housing means between a minimum and a maximum, wherein the limiting means and / or the housing means of a holding device at least in the maximum the volume of the storage space equivalent operating state against a restoring tendency of the housing device and / or the limiting device starting from a m operating state, from that to the minimum of the volume of the Memory storage equivalent operating state is durable in the direction of their to the minimum of the volume of the storage space equivalent operating state, stored in the presence of a request for starting the internal combustion engine in the storage device stored hydraulic fluid at least partially for filling a hydraulic circuit of the starting device from the storage device.

In order to becomes the hydraulic circuit of a hydrodynamic starting device by means of a hydraulic attachment or the Storage device for storing hydraulic fluid at the time a start of the internal combustion engine filled to the drive torque the switched-on internal combustion engine in each operating state of the Drivetrain in one to avoid safety-critical Transmitted to the operating conditions of the vehicle required extent to be able to.

through of the method according to the invention, during a hydrodynamic starting device via a pulse charging is filled, is a hydrodynamic starting device during a starting process of an internal combustion engine as possible supplied high hydraulic fluid flow rate. It will a filling of a hydrodynamic starting device in synchronous operating states in which a primary and secondary side or a pump and a turbine wheel rotate at the same speed, supported. In the synchronization point a hydrodynamic starting device is a particularly good Air separation in the interior at the inner radius in front and the air is then particularly easy from the area in which hydraulic lines into the interior, from the interior of a hydrodynamic Starting device executable.

at Differential speeds between the primary and secondary side or between the pump and turbine of the starting device Flow turbulence, which is the air separation influence negatively. Synchronous operating states of a starting device occur in particular when a traction in one of the starting device in relation to the internal combustion engine downstream transmission device is interrupted and the turbine wheel of the starter by the stationary output of a vehicle is not braked, wherein Such operating conditions of a transmission device or a Automatic transmission in selector lever positions P (parking) or N (neutral state) are given.

Further Advantages and advantageous developments of the invention result from the claims and the reference to the drawing principle described embodiments.

It shows:

1 a simplistic representation of a vehicle and

2 a greatly simplified flowchart of the method according to the invention.

1 shows a highly schematic representation of a vehicle 1 that a powertrain 2 with an internal combustion engine 3 and a transmission device 4 having. Between the internal combustion engine 3 and the transmission device 4 is present a hydrodynamic starting device 5 arranged at the in 1 illustrated embodiment of the vehicle 1 is designed as a hydrodynamic torque converter with associated converter lockup clutch.

The transmission device 4 is with several hydraulically operated switching elements 6 which executed by a not shown hydraulic system of the transmission device 4 that a transmission main pump 7 that is from the internal combustion engine 3 is driven by a gear shaft, is acted upon by hydraulic fluid. The hydraulic fluid is supplied by the transmission main pump 7 from a transmission oil sump 8th sucked and conveyed in hydraulic lines of the hydraulic system, wherein a system pressure and the driving pressures for the switching elements 6 be set operating state dependent on an electric transmission control unit and electrically or electro-hydraulically actuated actuators.

The transmission device 4 is presently designed as an automatic transmission and can in further embodiments of the vehicle 1 or the drive train 2 also be designed as an automated manual transmission or the like.

In addition, there is a storage device 9 provided for storing hydraulic fluid, as in principle from the DE 10 2006 014 756.1 or the DE 10 2006 026 980.2 is known.

The storage device 9 is formed with at least one of a housing device and a limiting device limited storage space, the volume of which is variable depending on an operating state of the loading and / or the housing device between a minimum and a maximum. The limiting device and / or the housing device are of a holding device at least in that to the maximum of the volume of the memory Room equivalent operating state against a restoring tendency of the housing device and / or the limiting device, starting from an operating condition which is different from the operating state equivalent to the minimum of the volume of the storage space, durable in the direction of their operating to the minimum of the volume of the storage space equivalent operating condition.

The internal combustion engine 3 In the present case, an engine-start-automatic system is assigned to the internal combustion engine in a manner known per se for reducing fuel consumption and for reducing pollutant emissions in predefined operating states of the drive train 2 automatically switch off and on again.

The method according to the invention for operating the hydrodynamic starting device will be described below 5 according to the illustration according to 2 , which is a schematic flow diagram of a preferred variant of the method according to the invention, described in more detail.

During the step S1, the procedure at a restart of the internal combustion engine 3 started by activating the ignition of the vehicle. That means the internal combustion engine 3 not started by the engine start-automation system. Subsequently, during a checking step S2, it is checked whether a selector lever over which a driver has different operating states in the transmission device 4 is in a selector lever position P (park), R (reverse), N (neutral), or D (forward). If the query result is negative, a branch back is made before step S2, whereas if the result of the query is positive, a further checking step S3 is run through.

In the checking step S3, a timer, which in principle both in a driver-side shutdown of the internal combustion engine by deactivating the ignition as well as in an engine start-automatic system-side shutdown of the internal combustion engine 3 is started, compared to a predefined threshold. If it is determined during the checking step S3 that the value of the timer is greater than the threshold value, a step S4 is executed. If the query result of step S3 is negative, the system branches back before step S2.

In advantageous variants of the method, it is provided that during the checking step S3, in addition to or as an alternative to the evaluation of the timer, it is checked whether there is a difference between a hydraulic fluid temperature and the switching-off time of the internal combustion engine 3 and a hydraulic fluid temperature at the time of request for starting the internal combustion engine 3 is larger than a predefined threshold value, step S4 being called in the case of a positive query result, and branching back to the checking step S2 if the query result is negative.

In further variants of the method, in addition to or as an alternative to the two above-described conditions, it is provided that the at the time of request for starting the internal combustion engine 3 present hydraulic fluid temperature is compared with a predefined threshold value and it is checked whether it is smaller than the threshold value, step S4 being called if the result of the query is positive and of the step of checking if the result of the query is negative 2 is branched back.

During the step S4, a switching valve 10 transferred to a switching position in which the memory device 9 with the hydraulic circuit de hydrodynamic starting device 5 directly connected. This will do this in the storage device 9 stored hydraulic fluid volume during a release of the storage device at least partially in the hydrodynamic starting device 5 introduced and used for pulse filling.

The changeover valve 10 is mechanically, hydraulically, pneumatically or electrically actuated and in other versions of the drive train 2 of the vehicle 1 also executable with multiple switch positions, in addition to the above-described alternative connections between the memory device 9 and the starting device 5 or the storage device 9 and the switching elements 6 the storage device in a further switching position simultaneously with the hydrodynamic starting device 5 and the switching elements 6 to be able to connect. In the latter switching position is a parallel supply of several hydraulic components by the storage device 9 possible. In this case, an optional volume control, for example by diaphragms or the like, is possible in order to obtain the different ones from the storage device 9 to be supplied to supply hydraulic components operating state-dependent with the respective required hydraulic fluid volume.

In addition to the supply of the hydrodynamic starting device 5 and the hydraulically actuated switching elements 6 the transmission device 4 can the system described above in a simple and cost-effective manner for the supply of additional hydraulic components of the drive train 2 of the vehicle 1 according to 1 be extended to these to avoid driving comfort affecting operating conditions in the presence of a request for starting an internal combustion engine with a defined hydraulic fluid volume to supply.

The storage device 9 is triggered during a subsequent to the step S4 step S5 and in the memory device 9 stored hydraulic fluid is in the hydraulic circuit of the torque converter of the starting device 5 spontaneously injected or initiated.

Subsequently, the storage device is refilled and verified during a checking step S6, whether the engine start-automatic system of the internal combustion engine 3 is activated. If the result of the query is negative, the method is ended during step S7, whereas if the result of the query is positive, the process returns to step S8, during which the changeover valve 10 is switched to a second switching position, is branched. In the second switching position of the switching valve 10 is the storage device with a hydraulically actuated switching elements 6 the transmission device 4 supplying hydraulic system connected, allowing further triggering of the storage device 9 now to supply the switching elements 6 the transmission device 4 is provided. Before the storage device 9 is triggered again in a step S9, additional triggering conditions S10, S11 and S12 further trigger conditions for the memory device 9 checked.

Thus, in the checking step S10, which directly follows the step S8, it is checked whether an ignition of the vehicle 1 switched on or off. If the query result is negative, a branch is made to step S7 and the method is ended. Will during the verification step 10 determines that the ignition is turned on, is branched to the verification step S11 and checks whether the selector lever is in position D or R, and is checked in a positive query result in the verification step S12, with the engine off 3 a request of the engine start-automatic system for switching on the internal combustion engine 3 is present. If the result of the verification step S12 is positive, the program branches to step S9 and the storage device 9 to supply the switching elements 6 the transmission device 4 triggered, branched back from step S9 before the verification step S10 and the memory device is refilled. Likewise, in the case of a negative query result, the checking steps S11 and S12 are branched back before the checking step S10.

In a further variant of the method according to the invention that is in the memory device 9 stored hydraulic fluid volume basically after each restart, which means a triggered by pressing the ignition of the vehicle starting process of the internal combustion engine 3 , at least partially for filling the hydrodynamic starting device 5 used.

Basically, the volume of the storage device 9 less than half the filling volume of the hydrodynamic starting device 5 executable, since in principle a small amount of underfilling the starter usually hardly measurable on the transmission capacity of the hydrodynamic starting device 5 effect. In addition, one of the internal combustion engine 3 drivable pump device of a starting device 5 supplying hydraulic system during a starting operation of the internal combustion engine parallel to the storage device, a hydraulic fluid volume flow available. This is the storage device 9 space-saving executable, which is particularly advantageous in an arrangement of the memory device in a transmission housing of a transmission device.

The above-described threshold values can be varied as a function of various operating state parameters of the assembly as well as the temperature of the hydraulic fluid and / or can be adapted to the storage device as a function of various adaptation routines during operation of the vehicle 9 to be able to control operating state-dependent.

1

vehicle

2

powertrain

3

Internal combustion engine

4

transmission device

5

hydrodynamic launch device

6

switching element

7

Main transmission pump

8th

Transmission oil sump

9

memory device

10

switching valve

S1-S12

step

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 102006014756 [0010, 0027]
• - DE 102006026980 [0010, 0027]

Claims (12)

Method for operating a hydrodynamic starting device ( 5 ) of a drive train ( 2 ) of a vehicle ( 1 ) with a preferably hydraulically actuated switching elements ( 6 ) running gear device ( 4 ), preferably with an engine-start-automatic system operable internal combustion engine ( 3 ) and with a memory device ( 9 ) for storing hydraulic fluid which is formed with at least one of a housing device and a limiting means limited storage space whose volume is variable depending on an operating condition of the limiting means and / or the housing means between a minimum and a maximum, wherein the limiting means and / or the Housing device of a holding device at least in the operating state equivalent to the maximum of the volume of the storage space against Rückstellbestrebens the housing device and / or the limiting device starting from an operating condition which is different from the to the minimum of the volume of the storage space equivalent operating state, in the direction of their the minimum of the volume of the storage space equivalent operating state are durable, characterized in that in the presence of a request for starting the internal combustion engine ( 3 ) in the storage device ( 9 ) stored hydraulic fluid at least partially for filling a hydraulic circuit of the starting device ( 5 ) from the storage device ( 9 ) is performed. A method according to claim 1, characterized in that the hydraulic circuit of the starting device ( 5 ) with the engine start-automatic system deactivated by the memory device ( 9 ) is acted upon with hydraulic fluid. A method according to claim 1 or 2, characterized in that the hydraulic circuit of the starting device ( 5 ) at a restart of the internal combustion engine ( 3 ) from the storage device ( 9 ) is acted upon with hydraulic fluid. Method according to one of claims 1 to 3, characterized in that when switching off the internal combustion engine ( 3 ) a timer is started, wherein the hydraulic circuit of the starting device ( 5 ) at a request for starting the internal combustion engine ( 3 ) from the storage device ( 9 ) is pressurized with hydraulic fluid when the timer is greater than a threshold value. Method according to one of claims 1 to 4, characterized in that the hydraulic circuit of the starting device ( 5 ) at a request for starting the internal combustion engine ( 3 ) from the storage device ( 9 ) is applied with hydraulic fluid when a difference between a hydraulic fluid temperature at the switching-off of the internal combustion engine ( 3 ) and a hydraulic fluid temperature at the time of request for starting the internal combustion engine ( 3 ) is greater than a threshold. Method according to one of claims 1 to 5, characterized in that the hydraulic circuit of the starting device ( 5 ) at a request for starting the internal combustion engine ( 3 ) from the storage device ( 9 ) is applied with hydraulic fluid when the hydraulic fluid temperature at the time of request for starting the internal combustion engine ( 3 ) is less than a threshold. Method according to one of claims 1 to 6, characterized in that the hydraulic circuit of the starting device ( 5 ) at a request for starting the internal combustion engine ( 3 ) from the storage device ( 9 ) is applied with hydraulic fluid when a selector lever for selecting an operating state of the transmission device ( 4 ) in a selector lever position for the operating state parking, engaged reverse gear, engaged forward gear or neutral state, in which in the transmission device ( 4 ) a power flow is interrupted, is located. Method according to one of claims 1 to 7, characterized in that in the memory device ( 9 ) stored hydraulic fluid volume at a request for starting the internal combustion engine ( 3 ) at least partially for driving the hydraulically operable switching elements ( 6 ) of the transmission device ( 4 ) is used when the engine start-up system is activated. Method according to one of claims 1 to 8, characterized in that in the memory device ( 9 ) stored hydraulic fluid volume at a request for starting the internal combustion engine ( 3 ) at least partially for driving the hydraulically operable switching elements ( 6 ) of the transmission device ( 4 ) is used when an ignition of the vehicle is turned on. Method according to one of claims 1 to 9, characterized in that in the memory device ( 9 ) stored hydraulic fluid volume at a request for starting the internal combustion engine ( 3 ) at least partially for driving the hydraulically operable switching elements ( 6 ) of the transmission device ( 4 ) is used when the selector lever in a selector lever position for the operating state engaged reverse gear or engaged forward gear of the transmission device ( 4 ) is located. Method according to one of claims 1 to 10, characterized in that the memory device ( 9 ) a valve control device ( 10 ) is associated with at least two switching positions, wherein in a first switching position of the hydraulic circuit of the starting device ( 5 ) and in a second switching position, the switching elements ( 6 ) of the transmission device ( 4 ) at a request for starting the internal combustion engine ( 3 ) is acted upon by hydraulic fluid of the memory device. Method according to one of claims 1 to 11, characterized in that in the memory device ( 9 ) stored hydraulic fluid at least partially in the hydraulic circuit of the hydrodynamic starting device ( 5 ) and at least partially for driving the switching elements ( 6 ) of the transmission device ( 4 ) is used.