FR2882002A1 - Drive train transmission for motor vehicle, has input shafts connected alternatively to heat engine of vehicle, output shafts connected to wheels of vehicle, and electrical motor connected to end of additional shaft arranged near engine - Google Patents

Abstract

The transmission has two concentric input shafts (1, 2) connected alternatively to a heat engine of a vehicle by concentric clutches (E1, E2) receiving a torque of the engine. Two output shafts (3, 4) are connected to the wheels of the vehicle by a differential (7), where the shaft (3) is shorter than the shaft (4). An electrical motor (26) is connected to an end of an additional shaft (5) arranged near the engine.

Description

DOUBLE CLUTCH GEARBOX FOR GROUP

MOTOPROPULSEUR_HYBRIDE

  The present invention relates to automobile vehicle gearboxes comprising a plurality of parallel shafts, each provided with a plurality of pinions.

  More particularly, it relates to a parallel shaft motor vehicle gearbox provided with a plurality of gears, comprising two concentric primary shafts alternately connected to the vehicle engine by a first and a second clutch, and two secondary shafts connected to the vehicle wheels by a differential.

  This invention has a preferred application, but not limited to, the gearboxes robotized concentric primary shafts, and double input clutch By publication DE 198 21 164, a gearbox of the type indicated above is known, called double clutch.

  A general problem of dual clutch gearboxes as described in this publication is their overall height, especially because of the large volume occupied by the double clutch close to the engine.

  A particular architecture and congestion problem also arises when one seeks to integrate such transmissions into a hybrid powertrain grouping a heat engine and an electric motor.

  The present invention aims to achieve a compact hybrid transmission from a gearbox dual input clutch.

  For this purpose, the gearbox has an additional shaft connected to an electric hybridization motor.

  This electric motor is preferably connected to the end of the additional shaft closest to the engine.

  According to a first embodiment, the electric motor is connected to the additional shaft by a drive member such as a metal chain.

  According to a second embodiment, it is connected to the additional shaft by a gear.

  The proposed measures are compatible with the constraints of space related to robotized gearboxes with double clutch.

  Thus, to clear an available space at the top of the box, opposite the engine, the first secondary shaft may be shorter than the second secondary shaft.

  Other features and advantages of the invention will become clear from reading the following description of a particular embodiment thereof, in conjunction with the accompanying drawings, in which: - Figure 1 is a schematic representation of In a first embodiment of the invention, FIG. 2 is a simplified cross section of FIG. 1, and FIG. 3 is a cross section of a second embodiment.

  The gearbox illustrated by FIG. 1 comprises two concentric primary shafts 1, 2 connected to the motor M. The primary shaft 1 passes inside the primary shaft 2, and protrudes from it on the side opposite to the motor. .

  Two secondary shafts 3, 4, and an additional shaft 5 are parallel to the primary shafts 1, 2. A double clutch system 6 and a differential 7 are shown schematically. The double clutch 6 comprises two concentric clutches El, E2, connected to the motor M. The first clutch El is also connected to the first primary shaft 1, while the clutch E2 is connected to the second primary shaft 2. Each of the clutches El , E2 can be placed in the disengaged or open position, where the corresponding primary shaft 1, 2 is independent of the motor M, or in the engaged or closed position, where the motor torque is transmitted to the corresponding primary shaft.

  Each of the secondary shafts 3, 4 is equipped, on the engine side, with a differential drive pinion referenced respectively 8 and 9. The two drive gears 8, 9 mesh with the same gear of the differential, so that the engine torque can be transmitted to the vehicle wheels by one or the other of the two secondary trees 3, 4. Note that Figure 1 is a schematic representation flat, trees, which in reality are not coplanar. The rotational link between the pinion gear 8 and the differential 7 is represented by dotted lines in FIG.

  Each secondary shaft 3, 4 carries several idle gears and jaw systems for securing the different idle gears of their secondary shaft.

  Starting from the end opposite the motor, the first primary shaft 1 carries three fixed gears 10, 11, 12, integral with it, while the second primary shaft 2, also carries three fixed gears 13, 14, 15.

  The second secondary shaft 4 carries the opposite side to the engine, two idle gears 16, 17, connected to the same double clutch 101. When the clutch 101 is in position a in the figure, the secondary shaft 4 is rotationally fixed to the pinion 16 When it is in position b, the same shaft 4 is rotatably connected to the pinion 17. The shaft 4 also carries, closer to the engine, another double clutch 102, thanks to which the idle gears 18, 19 can be selectively connected to the primary shaft 4, depending on whether the clutch is in position c or d in the figure.

  the same, the first secondary shaft 3 is equipped, in its remote part of the engine, a single clutch 103, with which its idler gear 20 can be secured to it in position e. The first secondary shaft 3 carries, on the motor side, an idle gear 21 and a double clutch 104, integral in rotation thereof. The first secondary shaft 3 also carries a pinion 23, rotating freely around the assembly comprising the pinion 21 and the 1 O double clutch 104.

  When the double clutch 104 is in the neutral position, the pinion 23, pinion assembly 21 and double clutch 104, as well as the primary shaft 3, are all three free in rotation, and independent of each other. When the dog 104 is in position f, the toothed wheel 22 is rotationally fixed to the pinion 21. When the dog 104 is in position g, the pinion 23 is rotationally fixed to the pinion 21.

  Finally, the additional shaft 5 carries, opposite the motor, a pinion 24, integral in rotation with it, and, on the motor side, a second fixed pinion 25.

  The pinion furthest from the motor on the primary shaft 1, is the pinion 10. It meshes with the pinion 16 of the second secondary shaft 4. The second secondary shaft 4 is as long as the sum of the lengths of the two primary shafts because it is also connected in its front part to the differential 7, by the pinion 9. Thus, the first secondary shaft 3 is shorter than the second secondary shaft 4.

  The pinion 11 meshes with the pinion 17, the pinion 13 meshes with the pinion 18, and the pinion 14 meshes with the pinion 19. Similarly, on the first secondary shaft 3, the pinion 12 meshes with the pinion 20, and the pinion 15 meshes with the pinion 21.

  The pinion 20, located farthest from the engine on the first secondary shaft 3, meshes with the pinion 12, which is the pinion mounted closest to the motor on the first primary shaft 1. The same pinion 12 meshes, in another direction space, with the pinion 24, which is the pinion mounted furthest from the engine on the additional shaft 5. The other pinion 25 of the additional shaft 5, meshes with the pinion 23 of the first secondary shaft 3. As indicated on the diagram, the pinion 24 of the additional shaft 5 which is farthest away from the engine, is therefore closer to or at the same axial distance as the pinion furthest from a first secondary shaft 3.

  The first secondary shaft 3 and the additional shaft 5, leave free the top of the box opposite the engine. The distance thus released corresponds to the sum of the thicknesses of the gears 16, 17, and the double clutch 101, arranged between them. As indicated in FIG. 1, the additional shaft 5 is connected at its other end to an electric motor 26, occupying in the power unit the location usually reserved for the starter. The electric motor is thus connected to the end of the additional shaft 5, the closest to the engine.

  According to the embodiment of Figure 1, which corresponds to Figure 2, the motor 26 is connected to the shaft 5 by a flexible member 27 (chain, belt or other), ensuring the transmission of torque between a pinion 28 of the 5 and a pinion 29 of the input shaft 31 of the motor 26. The implantation of an electric motor coupled to the box instead of a starter is authorized by the judicious arrangement of the shaft additional 5 on the top thereof, on the side of the heat engine M. This implementation allows a hybridization of the transmission, by arranging on the gearbox two movement inputs, respectively from the engine 'thermal engine and electric.

  In FIG. 2, the shafts of the box have not been shown, but the outside profiles of the corresponding pinion lines have simply been shown in a casing profile 30a. Thus the primary line la, 2a, meshes with the two secondary lines 3a, 4a, themselves in engagement with the differential line 7a. In accordance with FIG. 1, the primary line and the first secondary line 3a are linked to the additional line 5a. The latter is connected by the flexible drive member 27 to the electric motor 26.

  in the embodiment illustrated in FIG. 3, the transmission member 27 is replaced by an intermediate gear 32, 33 providing under the same conditions as this, the transmission of the movement between the pinion 28 (not shown) of the additional line 5a, and the input gear 31 of the electric motor 26.

  In conclusion, the invention makes it particularly advantageous to obtain a hybrid transmission from a gearbox with concentric primary shafts and double input clutch, exactly in the same size as this one. This arrangement is achieved in particular by the provision of an additional short shaft on the top of the box, close to the heat engine, which allows to integrate into the transmission an electric hybridization engine and instead of the starter, all leaving a space available at its other end.

Claims (7)

-7-CLAIMS   A parallel shaft motor vehicle gearbox having a plurality of torque gear gears, comprising two concentric primary shafts (1, 2) alternately connected to the vehicle engine by a first and a second clutch (E1, E2). ) receiving the torque of the engine, and two secondary shafts 3, 4, connected to the vehicle wheels by a differential (7), characterized in that it has an additional shaft (5) connected to an electric motor (26).   2. Gearbox according to claim 1, characterized in that the electric motor is connected to the end of the additional shaft (5) closest to the engine.   3. Gearbox according to one of the preceding claims, characterized in that the pinion (24) of the additional shaft (5) which is farthest from the engine is closer or the same axial distance as the pinion the most away from a first secondary shaft (3).   Gearbox according to Claim 1, 2 or 3, characterized in that the electric motor (26) is connected to the additional shaft by a flexible drive member (27).   Transmission according to claim 1, 2 or 3, characterized in that the electric motor (26) is connected to the additional shaft by a gear (32, 33).   Gearbox according to one of the preceding claims, characterized in that the first secondary shaft (3) is shorter than the second secondary shaft (4).   7. Gearbox according to one of the preceding claims, characterized in that the pinion (20) farthest from the engine, a first secondary shaft (3) meshes with the pinion closest to the engine of a first primary shaft (1).