FR2956175A1 - Automated dual clutch gearbox, has hollow shaft guided by bearing supported by clutch casing, where shaft extends until another bearing supported by clutch mechanism housing in part opposite to clutch casing - Google Patents

Abstract

The gearbox (1) has a first hollow shaft, a second hollow shaft (17) and a transfer shaft (18) placed in a clutch mechanism housing. A disjoint clutch (2) is arranged in a clutch casing (5) between a motor and the first shaft. Another disjoint clutch (3) is arranged at an opposite end of the housing. The transfer shaft continuously transmits movement of the motor in a direction of the second clutch. The first shaft is guided by a bearing supported by the clutch casing. The first shaft extends until another bearing is supported by the housing in a part opposite to the clutch casing.

Description

The present invention relates to automated gearboxes with disengaged double clutch.

More specifically, it relates to an automated gearbox concentric primary shafts in a mechanism housing and disjoint two clutches, comprising a first clutch arranged in a clutch housing between the engine and a first primary shaft of the box, a second clutch disposed at the opposite end of the mechanism housing connected to a second primary shaft, and a transfer shaft within the primary shafts, continuously transferring the movement of the motor towards the second clutch.

According to a known provision, some gearboxes with two disjoint clutches comprise hollow primary shafts, and a solid shaft, which transfers the movement of the motor to the opposite end of the box, inside the latter.

The transfer shaft can support all the rotating gears around it. Its function is then not only to transmit the torque from one end to the other of the box, but also to withstand the radial forces the rotating teeth around him during transmission torque. In the arrangement described by the publication EP 0 075 408, the design of the transfer shaft has the following characteristics: • a guide of the transfer shaft by the bearings arranged in each housing through the end gears in conjunction with clutches, and • short and insufficient guidance of these gears.

This stack has the disadvantage of being complex, and to use three needle stops working under pre-load. The invention aims to simplify the transfer shaft by limiting its sheet to the transmission of the engine torque to the clutch arranged at the opposite end of the box. For this purpose, it proposes a particular arrangement of this transfer shaft and torque input elements in the box in connection with the clutches.

It provides in particular that the first primary shaft is a hollow shaft, guided by a first bearing supported by the clutch housing, which extends to a second bearing supported by the mechanism housing in its opposite portion to the housing of clutch.

The gearbox preferably comprises a second hollow primary shaft guided externally by the second bearing, and guided internally by needle bearings around the first hollow primary shaft. According to a particular embodiment of this gearbox, the primary transfer shaft disposed inside the first primary shaft can be guided, motor side, by a needle sleeve interposed between itself and the odd primary shaft. and, opposite the motor, by a roller bushing interposed between itself and the even primary shaft. Thanks to this arrangement of the primary shafts and the transfer shaft, the flexural rigidity is provided by the odd primary shaft, and the role of the transfer shaft is well limited to torque transmission.

Other characteristics and advantages of the present invention will emerge clearly from a reading of the following description of a nonlimiting embodiment thereof, in conjunction with the appended drawings, in which: FIG. FIG. 1 is a partial enlargement of FIG. 1, and FIG. 2 is a sectional view of the primary shafts of the box. The gearbox 1, illustrated by the figures, is an automated gearbox with two disjointed clutches. It comprises two clutches 2, 3. The first clutch 2 is arranged between the motor (not shown) and the gearbox 1. It is connected to a first hollow primary shaft 4, dedicated to odd-order ratios. The first clutch 2 is housed in a clutch housing 5. It belongs to a coupling device, also comprising a damping flywheel 6, fixed on the crankshaft 7 of the engine. The actual clutch 2 is a dry clutch. It is composed of a reception plate 8, guided and carried by means of a bearing 9 by the odd primary shaft 4, a pressure plate 11, and a mechanism comprising mainly a diaphragm 12 and a clutch cover 13. The operation of the clutch 2 is the reverse of the usual operation of the manual transmission input clutches. It is open at rest, in order to ensure a safe situation of refuge in the event of a flight failure. Its closure requires a permanent push on the diaphragm 12. The receiving plate is guided and carried by the odd primary shaft 4, so that the force applied by the clutch abutment 14 on the diaphragm 13 is taken by the bearing 9 of the box, and not by the crankshaft 7. The damping flywheel 6 is fixed and mounted on the crankshaft 7. The clutch 2 is fixed and mounted on the odd primary shaft 4 of the box 1. The transmission of the movement of the damping flywheel 6 to the clutch 2 is ensured for example by a male groove on the receiving plate 8 and a female groove on the output flange 16 of the damping flywheel 6. The gearbox 1 is an automated gearbox with concentric primary shafts 4, 17, 18 in the mechanism housing 22 and two disjointed clutches 2, 3: it comprises a first clutch 2 arranged in the clutch housing 5 between the engine and the first primary shaft 4 of the box, and a second clutch 3 disposed at the opposite end of the mechanism housing 22. The transfer shaft 18 continuously transmits the movement of the motor towards the second clutch 3, placed at the other end of the box. This clutch is connected to a second hollow primary shaft 17, which is the primary shaft of the even ratios.

The first hollow primary shaft 4 is guided by a first bearing 36 supported by the clutch housing 22. It extends to the second bearing 37 supported by the mechanism housing 22 in its portion opposite to the clutch housing 5.

The second hollow primary shaft 17 is guided externally by the second bearing 37, and guided internally by needle bearings 46 (see FIG. 2) around the first hollow primary shaft 4. The shaft 17 is linked to the motor by the clutch 3 and by a transfer shaft 18, concentric and placed inside the two hollow primary shafts 4, 17. A splined sleeve 19 is fixed on a flange 21, fixed on the receiving plate 8 of the first clutch 2, he The latter thus ensures the filtering of the torsional vibrations of the engine, for the two clutches 2, 3. The second clutch 3 is for example of wet multi-disc type lubricated and cooled by the oil sparge. It is arranged in a dedicated compartment 22a of the mechanism housing 22, so as to adjust the oil level required for its proper operation regardless of the level required in the compartment 22b of the gears. It has an outer bell 23, welded to a splined sleeve 24, which is mounted on the even primary shaft 17. It also has an inner bell 26, welded to another grooved sleeve 27, mounted on the transfer shaft 18. Between the two bells 23, 26, is disposed a set of discs 28, alternately connected by splines, to one or other of the bells 23, 26. Half of the faces of the discs are coated with a material friction. They are framed by two pressure plates 29, 31. The plate 31 is actuated by a diaphragm 32 acting as a force multiplier lever. The diaphragm 32 is biased by a control fork 33, whose thrust is applied to it by a thrust bearing 34. In the embodiment described, the odd ratios are obtained from the first hollow primary shaft 4, and the even ratios are obtained from the second hollow primary shaft 17.

The odd gear fixed teeth are grouped on the motor side on the first hollow shaft 4, while the fixed teeth of the even ratios are grouped on the second hollow shaft 17, in the part of the box farthest from the engine. The arrangement of the fixed teeth between the bearing 36 of the clutch housing and the bearing of the mechanism housing 37 is highlighted in Figure 2. On the first hollow shaft 4, there is from the right to the left, the common teeth first and reverse gear 39, the third set of teeth 41, the fifth set of teeth 42. This makes it possible to benefit from the dry clutch described above, for first and reverse take-offs, to which it is well suited. On the second hollow shaft 17, from the right to the left are the fourth teeth 43 and the second teeth 44. The transfer shaft 18 is mounted in guide pins 46 inside the first hollow shaft 4 , itself mounted in other guide pins 46, inside the second hollow shaft 17. The transfer shaft 18 is guided, motor side, by a needle sleeve 46 interposed between itself and the first hollow primary shaft 4, and, opposite the motor, by a roller bushing 48, interposed between itself and the second hollow primary shaft 17. Are also shown, the axial bearing abutment 47 between the two hollow shafts, guide rollers 48 of the transfer shaft 18 and, on the right of the diagram, a seal 51 between the first hollow shaft 4 and the transfer shaft 18. The box 1 has two secondary shafts 52, 53, respectively in the upper part and in the lower part. The two drive gears 54, 56 of the bridge crown 57 are identical. The movement is transmitted by these two drive gears to the ring 57, fixed on a differential housing. The distance between the shafts of the box is determined by the diameters of the players in vis-à-vis. This constraint imposes a greater distance between the axis of the primary shafts 4, 17 18 and the axis of the secondary shaft 52 up between the axis of the primary shafts 4, 17 18 and the axis of the shaft. secondary low 53.

In the nonlimiting exemplary embodiment illustrated by FIGS. 1 and 1A, the first idle gear 58 is placed on the high secondary shaft 52 to allow short ratios, despite the fact that the odd primary shaft 4 is hollow. The first idle gear 58 has a second toothing 59 which meshes with the reverse idle gear 61, arranged on the lower sub-shaft 53. The first idle gear 58 also performs the reverse idler function, while the secondary high shaft 52 performs the reverse countershaft function.

Continuing to the left, the secondary high shaft 52 carries the third idler gear 62, then the fourth idler gear 63. A first dual synchronizer 64 can engage the first and third gear. A first simple synchronizer 65 makes it possible to engage the fourth gear. The low secondary shaft 53 carries, from right to left, the reverse idler gear 61, the fifth idler gear 66, then the second idler gear 67.

The commitment of the fifth and reverse gear is provided by a second double synchronizer 69, and that of the second gear, by a second simple synchronizer 71. In conclusion, the following points must be emphasized: • the odd primary shaft hollow, guided by the bearing supported by the clutch housing, extends as far as under the bearing supported by the mechanism housing, • the odd primary shaft is hollow to accommodate the transfer shaft, • the primary shaft pair, also hollow, is guided externally by the bearing supported by the casing of mechanisms; it is guided internally by needle bushings, inserted between itself and the odd primary shaft, • the transfer shaft, placed inside the odd primary shaft, is guided on the motor side by an interposed needle bush between itself and the odd primary shaft and side opposite the motor, by a roller sleeve interposed between itself and the even primary shaft.

Claims (10)

REVENDICATIONS1. Automated gearbox with concentric primary shafts (4, 17, 18) in a mechanism housing (22) and two disjoint clutches (2, 3) having a first clutch (2) arranged in a clutch housing (5) between the engine and a first primary shaft (4) of the gearbox, and a second clutch (3) disposed at the opposite end of the gear housing (22), a transfer shaft (18) continuously transmitting the motor movement towards the second clutch (3), characterized in that the first primary shaft (4) is a hollow shaft, guided by a first bearing (36) supported by the clutch housing (22), which extends to a second bearing (37) supported by the mechanism housing (22) in its opposite portion to the clutch housing (5). 2. Automated transmission according to claim 1, characterized in that it comprises a second hollow primary shaft (17) externally guided by the second bearing (37), and guided internally by needle bearings (46) around the first shaft hollow primary (4). Automated transmission according to Claim 1 or 2, characterized in that the transfer shaft (18) is arranged inside the first primary shaft (4). 4. Automated transmission according to claim 3, characterized in that the transfer shaft (18) is guided by a needle sleeve (46) interposed between itself and the first hollow primary shaft (4) on the side of the motor and by a roller bushing (48) interposed between itself and the second hollow primary shaft (17), on the opposite side to the motor. 5. Automatic gearbox according to one of the 35 preceding claims, characterized in that the first primary hollow (4) carries the fixed teeth (39, 41, 42) odd rank reports. 6. Automated transmission according to one of the preceding claims, characterized in that the second hollow primer carries fixed teeth (42, 44) of even rank ratios. 7. Automatic gearbox according to one of the preceding claims, characterized in that the fixed teeth fixed odd ratio ratios (39, 41, 42) are grouped on the motor side. 8. Automatic gearbox according to one of the preceding claims, characterized in that the fixed teeth of even rank ratios (42, 44) are grouped on the opposite side to the motor. 9. Automated transmission according to one of the preceding claims, characterized in that it comprises a first secondary shaft (52) carrying the first, third, fourth (58, 62, 63) idle gears. 10. Automated transmission according to claim 9, characterized in that it comprises a second secondary shaft (53) carrying the idler gears, fifth and second (61, 66, 67).