Drive device

The present invention relates to a drive device with an electric A machine according to the preamble of claim 1. In particular, the present relates to Invention, a drive apparatus for a motor vehicle, which in a having the form of a starter / generator unit configured electric machine.

Starter / generator systems are widely known and one hand enable a faster and quieter start of coupled thereto drive motor and on the other hand high generator power to provide energy for some consumers of the motor vehicle provide.

For designing such starter / generator systems are different known variants.

A first variant provides the use of a parallel to the drive shaft of Drive motor arranged generator or alternator before, the generator coupled or the alternator via a belt to the drive motor is. According to another variant, the starter / generator unit, a sweeping-use Dual clutch machine with mechanical energy storage used.

The two variants mentioned above have in common that the starter / generator unit is provided separately from the drive shaft of the drive motor. At a third variant of a drive device according to the preamble of claim 1 corresponds, however, is the (as crankshaft starter generator designated) Starter / generator unit is provided on the drive shaft.

The basic structure of such a drive device with an on Drive shaft arranged starter / generator unit, for example, the Publications WO 98/05882, DE 196 16 504 A1, DE 19645 943 A1, DE 197 05 610 A1 are taken or DE 197 45 995 A1. these known drive devices will drive the vehicle, an engine used serving its crankshaft with a starter / generator unit connected electric machine. The electric machine comprises a rotor and a stator surrounding the rotor, wherein the stator windings with the Motor vehicle battery are connected. The rotor of the electric machine is the output side via a transmission clutch with a gear connected.

Serving as the starter / generator unit electrical machine is different in two Modes operated. In an engine operating accepts the electrical Machine upon actuation of the starter key, the function of a starter or motor for starting the internal combustion engine. For this purpose, the stator windings supplied from the vehicle battery corresponding currents such that the Rotor is subjected to a start-up torque of the starting Engine allows. After starting the engine works the electrical machine in generator mode, in which the rotor on the crankshaft offset of the engine in rotation, and thus in the stator windings a voltage is induced, which, for example, to power the Board network and the connected consumer of the motor vehicle is used.

As has been described above, in this known generic The drive devices located on the crankshaft starter / generator unit on the output side of the engine between the combustion engine and the transmission disposed. Such an arrangement has an axial extension the entire drive device result. In addition to the Assembling apparatus used for assembling the gear and the motor serve, due to the arrangement of the starter / generator unit between the engine be and changed and adapted to the gearbox, giving rise to corresponding costs in the has serial production of the engine-transmission unit result.

The present invention is therefore based on the object, a driving device arranged with one on a drive shaft of a drive unit provide electrical machine, which is as simple and cheap and realized without a substantial axial extension of the drive device leaves.

This object is according to the present invention by a drive device solved with the features of claim 1. The subclaims define preferred and advantageous embodiments of the present invention.

According to the invention, in particular in the form of a starter / generator unit with a rotor and a stator electric machine configured on the Gear side facing away from the drive shaft, that on the opposite side of the output Side of the motor is disposed. When using an internal combustion engine therefore this between the one end of the drive or crank shaft coupled with the electrical machine and the other end of Crankshaft coupled manual or automatic transmission arranged.

The present invention enables the arrangement of the electrical machine the drive shaft without substantial changes to the engine, the gearbox or to the Mounters. The invention can be without substantial axial extension the arrangement realized. The additionally required axial space is on the maximum diameter of the starter / generator unit is limited. Considering all aspects is therefore the most cost-effective Variant to arrange the electrical machine to the drive shaft.

Furthermore, the inventive arrangement is extremely friendly customer service, Since the electric machine is easily accessible from the outside.

The direct connection of the electric machine to the crankshaft has in the Rule oversizing of the required electronics and dimensioning the electric machine to the starter operating result. This disadvantage can be avoided if the electric machine via mechanical Between elements is connected to the crankshaft, wherein a significantly lower Starting performance of the system is made possible. As mechanical intermediate elements are in particular an auxiliary gearbox or a clutch in question.

By using a between the electric machine and the crankshaft arranged coupling can in a conventional and a belt driven air compressor also a stationary climate control are achieved when when motor is configured as the starter / generator unit electrical Machine is uncoupled from the motor while the starter / generator unit in the Electric motor operation mode is operated to the air compressor mechanically to operate on the rotor. With the engine running, however, the air conditioning compressor still mechanically driven by the crankshaft.

Another advantage is the embodiment of the electrical machine of the external rotor variant wherein, for example, the air conditioning compressor directly via a gear can be mechanically driven with the outside of the rotor. Also in this case is a stationary climate possible.

The invention is described with reference with reference to the drawing preferred embodiments described.<dl tsize="7"><dt>Fig. 1</dt><dd>shows the use of a driving apparatus according to a first embodiment of the present invention in a motor vehicle,</dd><dt>FIG. 2</dt><dd>shows the construction of a driving apparatus according to a second embodiment, of the present invention, and</dd><dt>Fig. 3</dt><dd>shows the construction of a driving apparatus according to a third embodiment of the present invention.</dd></dl>

In Fig. 1, an engine 1 of a motor vehicle is shown, via whose driven by the piston of the internal combustion engine 1, a crankshaft 2 Torque through a transmission clutch (or in an automatic transmission over a transducer) to the transmission input shaft of a manual or automatic 3 transferred to the drive of the mounted on the chassis 4 of the motor vehicle wheels becomes.

On the opposite side of the transmission 3 of the engine 1 is a electric machine arranged. This electric machine serves as Starter / generator unit and permits an easy start of the engine 1 and on the other hand a high power generator, to enable the Starting the engine 1 energy for some consumers of the motor vehicle provide. To this end, comprises the electric machine a with the crankshaft 2 is coupled to the rotor 8, which within one or more Stator windings 7 is rotatably arranged.

The electric machine 8, for example, in the form of a 42-volt asynchronous be configured. Likewise is the embodiment in the form of a synchronous machine possible. During engine operation, the electric motor takes over when pressing of the starter key, the function of a starter for starting the internal combustion engine 1. For this purpose, the stator windings 7 a performance and Steuerelektromkeinheit 11 a corresponding energy from the vehicle battery 12 supplied so that the rotor 8 is subjected to a starting torque, which enables the starting of the engine first After starting the Internal combustion engine 1 is the electric machine in generator mode, wherein the rotor 8 on the crankshaft 2 of the engine 1 in rotation is added, and thus induces a voltage in the stator windings 7, which used for supplying power to various consumers of the motor vehicle. Thus, the voltage supplied from the stator 7 and the corresponding rotation current is inter alia of the unit 11 in a DC supply voltage of the electrical system or the connected consumer of the motor vehicle and the vehicle battery 12 converted.

The vehicle battery 12, for a 42V vehicle electrical system in lead technology, lithium-ion technology, Nickel-metal hydride or ultracap technology be designed.

In the embodiment shown in FIG. 1, the rotor 7 of the electrical Machine connected via a coupling 9 to the crankshaft second Furthermore, a running over a pulley 5 poly-V-belt 6 is provided, wherein running internal combustion engine 1 via the crankshaft 2 to the mechanical drive For example, an air compressor can be used 10th By using the additional coupling 9 on the opposite side of the transmission 3 Crankshaft 2, it is independent of the embodiment of the transmission the third

For cold start, the clutch can 9 from the control electronics unit 11 first be opened and supplied to the starter / generator unit energy to it in the operate motor operation. Has the rotor 8 reaches a sufficiently high rotational speed, can be closed 9 the clutch, which is a mechanical coupling has between the rotor 7 and the crankshaft 2 to the sequence, so that the crankshaft 2 'Pulled up' to the speed of the rotor 8 is. Soft reset may analogous to carried out a cold start or with the clutch engaged from the beginning 9 will.

A further advantage with use of the clutch 9 shown in Fig. 1, that, even at standstill of the engine 1, a stationary air conditioning is possible. For this purpose, the clutch 9 is at standstill of the combustion engine 1 is released, the electric machine and the rotor 8 from the internal combustion engine 1 and the crankshaft 2 to uncouple. Subsequently, the electric machine operated in motor mode, ie the stator 7 is supplied 11 electric power from the power and control electronics unit around the rotor 8 in rotation. The one with the air compressor 10 associated belt 6 is an additional belt shaft 18 to the clutch 9 such a manner that the belt shaft 18 in this case continues from the rotor 8 can be driven, so that the operation of the air compressor 10 even at A standstill of the vehicle is possible. During running of the engine 1 is Air compressor 10 then driven by the crankshaft. 2

In FIG. 2, a variant of the embodiment shown in Fig. 1 is shown, wherein the electric machine designed in accordance with the so-called external rotor variant , that is, the rotor 8 of the electric machine is externally around the stator 7 rotatably mounted. In this case, the air compressor 10 directly over the rotor 8 by means of a gear rim 14, which via a gearing (13) with the outside is coupled to the rotor 8, are driven. The Poly-V belt shown in Fig. 1 6 can then be omitted. Also in this embodiment is a Stationary climate control possible when at standstill of the engine 11, the Coupling dissolved 9 and the electric machine is operated in the motor mode.

Instead of a clutch between the electric machine may be 7, 8 and the crankshaft Be provided 2, a transmission, especially a shiftable transmission. Such a transmission may vary according to design of the electrical machine and the Electronics either by reversing torque of the electric machine and Switching the translation after starting as a start or support by switching the translation in the generator mode to increase the regenerative matic serve power in the lower speed range. The transmission would in this serve case as high drive. It is also a controllable change provide. In FIG. 3, such an embodiment is shown, wherein the Crankshaft 2 of the internal combustion engine 1 coupled with a planetary gear train is, which is on the other hand coupled to the rotor 8 of the electric machine. Here, a shown in FIG. 3, ring gear 16 via a helical gearing of a Planet gear 15 is switched, so that it dependent on the torque direction for booting the block of the engine 1 is braked. In this case, the Translation example 4: 1. For generator operation, the ring gear 16 however, blocked by a sun gear 17, the gear ratio 1: 1. A switchover of the translations is also freewheels or electromechanical conceivable.

In the embodiments shown in Figs. 1-3, the coupling should 9 or the Transmission include 15-17 damper and / or vibration absorber to of the electric machine and the rotor of which 8 may be on the crankshaft suppress 2 transmitted vibration and quiet operation of the Generator enable.

<b>LIST OF REFERENCE NUMBERS</b>

<dl tsize="3" compact="compact"><dt>1</dt><dd>internal combustion engine</dd><dt>2</dt><dd>crankshaft</dd><dt>3</dt><dd>gear</dd><dt>4</dt><dd>landing gear</dd><dt>5</dt><dd>pulley</dd><dt>6</dt><dd>belt</dd><dt>7</dt><dd>stator</dd><dt>8th</dt><dd>rotor</dd><dt>9</dt><dd>coupling</dd><dt>10</dt><dd>air compressor</dd><dt>11</dt><dd>Power and control electronics</dd><dt>12</dt><dd>battery</dd><dt>13</dt><dd>gearing</dd><dt>14</dt><dd>gear</dd><dt>15</dt><dd>planet</dd><dt>16</dt><dd>Hoblrad</dd><dt>17</dt><dd>sun</dd><dt>18</dt><dd>belt shaft</dd></dl>