DE102008064291A1 - Vehicle i.e. hybrid vehicle, has electrical machine indirectly connected with transmission, where electrical machine and internal-combustion engine are connected by separation clutch i.e. dosed proportional clutch, in detachable manner - Google Patents

Abstract

The vehicle (1) i.e. hybrid vehicle, has an electrical machine (3) indirectly connected with a transmission (4), where the electrical machine and an internal-combustion engine (2) are connected by a separation clutch (5) i.e. dosed proportional clutch, in a detachable manner. The electrical machine and the transmission are connected by a transducer (6) and a bypass clutch (7). The bypass clutch is arranged parallel to the transducer. Different parameter sets are stored in a control unit. An independent claim is also included for a method for starting an internal-combustion engine while driving a vehicle.

Description

The The invention relates to a vehicle, in particular a hybrid vehicle, the by means of an internal combustion engine and / or an electric machine is drivable, having a gear and a clutch, wherein the electric machine is connected to the transmission and the internal combustion engine and the electric machine by means of the separating clutch separably connected are. The invention further relates to a method for starting the internal combustion engine while driving the vehicle.

A vehicle having an internal combustion engine, an electric machine, a transmission and a disconnect clutch for a vehicle is known from DE 100 08 344 A1 known. This document shows the arrangement of the separating clutch between the engine and electric machine. The electric machine is used in the disclosed vehicle to deliver assistive torque during a shift of the transmission. For this purpose, the electric machine is connected to the transmission side of the separating clutch.

Also the DE 10 2005 016 117 A1 shows a vehicle with an internal combustion engine, an electric machine, a transmission and a disconnect clutch for a vehicle to assist a shift. The electric machine is connected in the disclosed in this document vehicle with the internal combustion engine associated side of the separating clutch.

It is still through the DE 101 45 955 A1 discloses an electric machine of a hybrid drive, which is used to assist a shift operation or for starting an internal combustion engine at the beginning of the drive of the vehicle in a low speed range.

One Hybrid vehicle is a vehicle in which at least two energy converters and two in-vehicle energy storage systems available are to power the vehicle. Energy converters are for example Electric and internal combustion engines, energy storage, for example, batteries or fuel tanks.

The individual energy converters in the hybrid drive can be different work together, either in parallel, then act the drives simultaneously on the part to be moved, or serially, then only one drive works directly on the moving part, while the other only provides power that converts the direct-acting Drive is supplied.

Out Various reasons serve in hybrid vehicles with electric and internal combustion engines latter mainly the propulsion, while the electric machines in selected Situations, for example, for starting the internal combustion engine on Start of the journey of the vehicle or for support a switching operation, are used.

hybrid vehicles with a powertrain running as a single-shaft parallel hybrid is, as a rule, have an electric machine connected to the drive axle on, via a clutch also with an internal combustion engine connected is. Depending on the switching position of the separating clutch can Vehicle by the internal combustion engine, the electric machine or both units are operated. When operated by the internal combustion engine can the electric machine either as a motor as a torque source or be used as a generator for charging the battery.

In front In this background, the invention is based on the object Vehicle and a method of the type mentioned in such a way that when driving, especially in a medium and / or high Speed range, the vehicle with hybrid drive, which only from an electric machine is driven, the start of an internal combustion engine without loss of comfort for the driver of the vehicle possible becomes.

These Task is solved with a vehicle according to the Features of claim 1. The dependent claims relate particularly expedient developments of the invention.

Disconnecting clutches are switchable clutches that allow separation of drive side and driven side. Depending on the application, this may be necessary during standstill or during operation. Due to a grinding operating condition, disconnect couplings with variable slip cause a speed adjustment. According to the invention, a vehicle is provided in which the separating clutch is a metered proportional clutch. This makes it possible to keep constant the torque on the drive wheels during the closing of the separating clutch. Without the devices according to the invention, the drive torque at the drive wheels would only be lower due to the start of the internal combustion engine since part of the torque of the electric machine is required for the start of the internal combustion engine, and then, at the output of the internal combustion engine, abruptly much larger than desired by the driver. This represents a major limitation of comfort and driving safety. By the design of the clutch as a proportional clutch this can be brought into controlled slip during startup, whereby while increasing the torque of the electric machine this process without a loss of comfort for the driver of the vehicle possible is.

While the starting process are preferably vibration damping Links used in the drive train to enter for the driver to avoid noticeable jerking during the changeover. It is advantageous that the electric machine and the transmission means a converter and a lockup clutch are connected. This makes it possible that the propulsion torque of the vehicle can be kept constant. The start of the internal combustion engine is imperceptible to the driver and thus comfortable. It is favorable that the lock-up clutch is arranged parallel to the transducer.

It is favorable that the vehicle has a control unit, in which various parameter sets are deposited, whereby the time and duration of the use and / or the adjustment of Disconnect coupling, electric machine, internal combustion engine, lockup clutch and / or transmission is adjustable. This makes it possible that depends on the operating condition of the vehicle and the torque request the driver of the starting process is feasible. The operating condition of the vehicle may preferably be determined by speed, propulsion torque, Desired torque and desired torque gradient, drive ratio, detected road gradient, energy content and efficiency of the electrical system or by detected system errors become. Will a spontaneous torque build-up on the drive wheels demanded, for example when accelerating for a passing process, the mentioned single operations have to be fast in time successively or partially at the same time, which is a lower comfort results.

The Task is further solved by a method according to the Features of claim 6. The dependent claims relate particularly expedient developments of the invention.

According to the invention Thus, a method is provided in which one between an internal combustion engine and an electric machine connected to the transmission Disconnecting clutch is closed, the torque of the electric machine according to the torque transmitted by the separating clutch is increased, the internal combustion engine depending on the required and achievable by the internal combustion engine torque is fired / started and, in particular after the start of the internal combustion engine, the torque of the electric machine according to the increase of the torque the internal combustion engine is reduced, whereby changes the date of commencement of the individual process steps and / or changes the duration of the individual process steps the degree of comfort of the start the internal combustion engine is adjusted.

hereby It is possible that the acting on the output sum torque the electric machine and the internal combustion engine a default torque follows, reducing the drive torque on the drive wheels is not affected by the start of the internal combustion engine. The Duration of the individual processes for starting the internal combustion engine depends on the desired degree of comfort. By the adjustability of the time and the duration of use and / or the adjustment of separating clutch, electric machine, internal combustion engine, lock-up clutch and / or gearbox, it becomes possible, depending on the starting process From the operating condition of the vehicle and the torque request of the driver perform. The operating state of the vehicle may be preferred through speed, propulsion torque, desired torque and desired moment gradient, Drive ratio, detected road gradient, energy content and efficiency of the electrical system or through detected system errors are described.

Becomes called for a spontaneous torque build-up on the drive wheels, for example, when accelerating for an overtaking operation, the mentioned single operations have to be fast in time successively or partially at the same time, which is a lesser Comfort has the consequence. The boot process is therefore between high Comfort, combined with a long-lasting take-off, and sportiness, connected with a fast start process, scalable. disconnect couplings are switchable clutches, which are separating drive side and enable driven side. That may vary depending on the application be necessary at standstill or during operation. By a grinding operating condition cause disconnect couplings with variable slip, a speed adjustment.

Of the Start of the engine in the moving, from the electric machine powered vehicle should be as comfortable as possible, so without noticeable torque difference at the drive wheels take place, with the duration of the starting process on the request of the driver is dependent. A quick startup is only for restrictions in comfort possible. Before starting, the lock-up clutch, depending on the operating condition of the vehicle and the Powertrain, open, in slip or closed be. Therefore, it is favorable that, before closing the clutch is started, the lock-up clutch is pressed. The star process is thereby depending on the driver's request scalable.

With a closed lock-up clutch it is favorable that, before closing the disconnect clutch is started, the lock-up clutch is opened and / or slipped. As a result, disturbances are damped and it is possible to drive the electric machine during the subsequent closing of the separating clutch in speed-controlled operation. After the start of the internal combustion engine and when producing a frictional connection to the separating clutch, the lock-up clutch is closed again. Thus, the initial state can be restored.

Cheap it is that when closing the clutch a suitable and / or desired speed of the electric machine of a Control unit is specified. This will cause errors in the Pilot control of the electric machine with the transmitted torque the separating clutch balanced, and the in-slip lock-up clutch and the transducer act as a damping unit, so that any vibrations occur.

The invention allows numerous embodiments. To further clarify its basic principle, one of them is shown in the drawing and will be described below. This shows the drive train of a vehicle 1 with a hybrid drive. In the illustrated hybrid vehicle, the drive axle 8th and about these the drive wheels 9 from an electric machine 3 and / or an internal combustion engine 2 driven. The internal combustion engine 2 and the electric machine 3 are a gearbox 4 with the drive axle 8th connected. The vehicle 1 is preferred by the electric machine 3 driven. The internal combustion engine 2 is with the electric machine 3 through a separating clutch 5 separably connected. Between the transmission 4 and the electric machine 3 is designed as a torque converter transducer 6 and a lock-up clutch 7 intended.

Will the vehicle 1 exclusively from the electric machine 3 driven, it may be necessary for different reasons while driving the internal combustion engine 2 to start. Possible reasons, for example, a torque requirement on the drive wheels 9 that the electric machine 3 can not provide, or be a nearly exhausted electric energy storage, which by means of a regenerative use of the electric machine 3 should be replenished. Without the devices and methods according to the invention would by the start of the internal combustion engine 2 the drive torque at the drive wheels 9 first lower and then suddenly much larger than desired by the driver. This represents a strong limitation of comfort and driving safety.

Is a start request for the internal combustion engine 2 before and is the lock-up clutch 7 closed, so the lock-up clutch 7 on the gearbox 4 put into slippage and the speed of the electric machine 3 rises. The acceleration-adjusted torque of the electric machine 3 shares in lockup clutch 7 and transducers 6 on. The speed of the electric machine 3 is now continuously controlled to a predetermined value by a controller, which is suitable for the implementation of the driver's request, at the same time is the disconnect clutch 5 closed. About the closing separating clutch 5 becomes the internal combustion engine 2 pulled up by the electric machine and, if the filling of the cylinder allows the representation of a desired torque, by releasing the injection, the ignition started. The torque of the electric machine 3 is doing according to the currently of the separating clutch 5 transferred torque during the towing process piloted. After the start of the internal combustion engine 2 the speed specification is suspended and the sum torque of the electric machine 3 and internal combustion engine 2 is set according to the driver's request. In this way, the transmission input torque and thus the drive torque at the drive wheel 9 held at the setpoint desired by the driver. Is at the separating clutch 5 the traction adjusted, so the lock-up clutch 7 closed again.

1

vehicle

2

Internal combustion engine

3

electric machine

4

transmission

5

separating clutch

6

converter

7

lock-up clutch

8th

drive axle

9

drive wheel

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 10008344 A1 [0002]
• DE 102005016117 A1 [0003]
• - DE 10145955 A1 [0004]

Claims (10)

Vehicle ( 1 ), in particular hybrid vehicle, which by means of an internal combustion engine ( 2 ) and / or an electric machine ( 3 ) is drivable, a transmission ( 4 ) and a separating clutch ( 5 ), wherein the electric machine ( 3 ) indirectly with the gearbox ( 4 ) and the internal combustion engine ( 2 ) and the electric machine ( 3 ) by means of the separating clutch ( 5 ) are separably connected, characterized in that the separating clutch ( 5 ) is a metered proportional clutch. Vehicle ( 1 ) according to claim 1, characterized in that the electric machine ( 3 ) and the transmission ( 4 ) by means of a transducer ( 6 ) and a lock-up clutch ( 7 ) are connected. Vehicle ( 1 ) according to claim 2, characterized in that the lock-up clutch ( 7 ) parallel to the transducer ( 6 ) is arranged. Vehicle ( 1 ) according to one of claims 1 to 3, characterized in that the starting sequence for the start of the internal combustion engine ( 2 ) at one of the electric machine ( 3 ) driven, moving vehicle ( 1 ) is scalable. Vehicle ( 1 ) according to one of the preceding claims, characterized in that the vehicle ( 1 ) has a control unit in which various parameter sets are stored, whereby the time and the duration of the insert and / or the adjustment of separating clutch ( 5 ), Electric machine ( 3 ), Internal combustion engine ( 2 ), Lock-up clutch ( 7 ) and / or transmission ( 4 ) is adjustable. Method for starting the internal combustion engine ( 2 ) while driving a vehicle ( 1 ), in which one between an internal combustion engine ( 2 ) and one with the transmission ( 4 ) connected electric machine ( 3 ) arranged separating clutch ( 5 ) closed, the torque of the electric machine ( 3 ) corresponding to that of the separating clutch ( 5 ) transmitted torque increases, the internal combustion engine ( 2 ) depending on that of the internal combustion engine ( 2 ) requested and achievable torque started and, in particular after the start of the internal combustion engine ( 2 ), the sum moment of the electric machine ( 3 ) and the internal combustion engine ( 2 ) is adjusted according to the driver's default torque, wherein by changing the timing of the beginning of the individual proceedings rensschritte and / or by changing the duration of the individual process steps of the degree of comfort of the start of the internal combustion engine ( 2 ) is set. Method according to claim 6, characterized in that before the closing of the separating clutch ( 5 ), a lock-up clutch ( 7 ), in particular is brought into slippage. A method according to claim 7, characterized in that after the start of the internal combustion engine ( 2 ) and when producing a required frictional connection on the separating clutch ( 5 ) the lock-up clutch ( 7 ) is closed. Method according to at least one of the preceding claims 6 to 8, characterized in that during the grinding of the separating clutch ( 5 ) the speed of the electric machine ( 3 ) from a control unit of the vehicle ( 1 ) is given. Method according to at least one of the preceding claims 6 to 9, characterized in that the specification of the rotational speed of the electric machine ( 3 ) from the control unit based on the torque at the converter ( 6 ) and / or the lock-up clutch ( 7 ) and a default torque, for example, a desired torque of the driver, is determined.