NL1028799C2 - Drive for vehicle, has first drive line which can be interrupted by means of disengagement which is present between second and third gearwheels - Google Patents

Abstract

A differential (D) is connected to the outgoing shaft (5) of a transmission (T) via a first drive line (I) having an intermediate shaft (9) with thereon a second gear wheel (t2) interlocked with first and third gearwheels (t1,t3). The first drive line can be interrupted by means of a disengagement (K1) which is present between the second and third gearwheels. Second driveline (II) is provided between the differential and the outgoing shaft. The second drive line has a reverse shaft (11), which is parallel to the intermediate shaft, with a reverse gear wheel (ta) that is interlocked with a gear wheel (7) connected to the differential, and a fourth gear wheel (t4) which can be connected to the reverse gear wheel and is interlocked with the second gear wheel. The second drive line can be interrupted by an additional clutch (K2) which is present between the reverse gear wheel and the fourth gear wheel.

Description

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Drive fitted with a continuously variable transmission and a switchable reverse · axle 5 DESCRIPTION:

FIELD OF THE INVENTION

The invention relates to a drive comprising a drive source, a continuously variable transmission with an input shaft that is coupled to the drive source and an output shaft with a first gear thereon, a coupling present between the drive source and the input shaft of the transmission and a differential coupled via a drive line to the output shaft of the transmission, which drive line comprises an intermediate shaft with a second gear thereon engaging the first gear and a third gear engaging a gear differential with the differential connected gear, which intermediate shaft is present between the first gear on the output shaft and the differential.

More in particular, the invention relates to such a drive for use in a vehicle.

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State of the art.

Such a drive for use in a vehicle is generally known for vehicles which are provided with a continuously variable transmission. In the known drive, a planetary gear set is provided between the drive source and the continuously variable transmission, a rotation body of which can be braked and the two other rotation bodies, which are connected to the drive source and the input shaft of the transmission, can be coupled to each other. By coupling these two rotational bodies with each other, this drive, applied in a vehicle, can be used to drive forwards and by disconnecting them and blocking the brake, they can be driven backwards.

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Summary of the invention.

An object of the invention is to provide a drive of the type described in the preamble, wherein with a simple construction the possibility is created for being able to reverse. To this end, the drive according to the invention is characterized in that the drive line can be interrupted by means of a disconnection present between the second and third gear, and the drive is further provided with a further drive line between the differential and the output shaft of the transmission, which further drive line comprises a reverse shaft 10, which is parallel to the intermediate shaft, with a reverse gear which engages the gear connected to the differential, and a fourth gear which can be coupled to the reverse gear and in engages with the second gear, and which further drive line can be interrupted by a further coupling, which is present between the reverse gear and the fourth gear. The decoupling can here, for example, uncouple the second gear 15 from the intermediate shaft, and the further coupling can, for example, uncouple the reverse gear from the reverse shaft.

Instead of a planetary gear set, with the drive according to the invention, the reversing function is realized by an additional reversing shaft, wherein the differential can be switched with the transmission via the intermediate shaft or the reversing shaft. This is a simpler and cheaper construction than that of the known drive and moreover this construction can suffice with less axial installation space than the known construction due to the lack of the planetary gear set. The uncoupling and the further coupling can be designed as form-locked couplings, for example claw couplings. Moreover, by closing the disconnection and the further coupling, a parking function can be obtained in which the wheels are blocked.

It is noted that from US 4,459,872 a drive is known in which the load can be driven in a direction opposite to the normal direction by a reversing shaft which is parallel to the output shaft of the driving source and on which two gear wheels are present, one of which is mounted in engages with the large gear of the final transmission. However, in this case the other gear wheel engages with a gear wheel present on the output shaft of the drive source and not with a gear wheel present on an intermediate shaft, as is the case with the construction according to the invention. If this construction were applied to the known drive, a drive would be created with two parallel drive lines that both drive the vehicle in the forward direction. In order to ensure that the further drive line drives the vehicle in the reverse direction, the drive must be further adjusted and, moreover, various adjustments are possible.

It is further noted that a drive is known from JP 61294247, wherein the drive line for the forward direction comprises an intermediate shaft and wherein the further drive line for the reverse direction comprises a reverse axle with two gear wheels thereon.

However, in this case the two gears are in engagement with the respective one of the gears present on the reverse axle and a further gear on the output shaft of the transmission. Thus, none of the gears on the reversing shaft engage the gear connected to the differential as is the case with the drive according to the invention. If the construction of the drive known from US 5,085,302 were to be applied to this drive, a drive would be obtained in which one of the gear wheels on the reversing shaft is engaged with the gear connected to the differential and the other on the reversing shaft gear present in engagement with the further gear on the output shaft of the transmission. Also in this way two drive lines are obtained which drive the vehicle in the same direction and a further adjustment must be made in order to be able to drive the vehicle in the opposite direction with one of the drive lines, whereby again various adjustments are possible.

An embodiment of the drive according to the invention is characterized in that the drive further comprises a coupling mechanism which couples the differential via the drive line to the output shaft of the transmission by closing the disconnection and / or couples the differential via the further drive line to the closing the output shaft of the transmission by the further coupling.

Preferably, the disconnection couples the second and third gear wheels on the intermediate shaft directly with each other. The drive torque then passes through the disconnection 30 and not through the intermediate shaft. As a result, the intermediate shaft does not have to be provided with splines, so that the intermediate shaft and the gear wheels can be made simpler.

Preferably, the reverse gear and the fourth gear are mounted on the reverse axle and can be directly coupled to each other. If the further clutch is open (when driving forward), the reverse gear and the fourth gear turn in the opposite direction. If the reverse gear and the fourth gear were mounted with respect to each other, the maximum difference speed becomes too great. To prevent this, the reverse gear and the fourth gear are separately relative to. mounted in the fixed world, each with a radial and an axial bearing. The very small forces can be absorbed by small pivot bearings or plain bearings.

If the uncoupling and the further coupling are designed as form-locked couplings, the two coupling halves can only be brought into engagement with each other during the standstill of the vehicle. This can be done by activating wheel brakes. To do this, the driver must press the brake pedal with his foot while switching the reverse gear on or off. An embodiment of the drive according to the invention in which this is not necessary is characterized in that the coupling is present between the drive source and the transmission, and a brake is present between the coupling 15 and the gear wheel coupled to the differential. This brake can be activated when moving the control lever of the automatic transmission in a vehicle to the reverse position. The brake can only brake the vehicle here and not like the known drive in which the brake also has a drive-off function. As a result, the brake can be made lighter and simpler than the brake with the known drive. The brake is preferably present between the clutch and the transmission.

A further embodiment of the drive provided with a brake is characterized in that the transmission can only be coupled via the coupling to the drive source. By this is meant that the transmission cannot, for example, be coupled to the drive source via a bypass transmission parallel to the coupling between the transmission and the drive source.

Brief description of the drawings.

The invention will be explained in more detail below with reference to exemplary embodiments of the drive according to the invention shown in the drawings.

Hereby shows:

Figure 1 is a schematic representation of a first embodiment of the. Drive according to the invention;

Figure 2 shows the drive shown in Figure 1 in side view;

Figure 3 shows a practical layout of the drive shown in Figure 1;

Figure 4 shows a slightly different practical layout of the drive shown in Figure 1;

Figure 5 shows a schematic representation of a second embodiment of the drive according to the invention;

Figure 6 shows the drive shown in Figure 5 in side view;

Figure 7 shows a practical layout of the drive shown in Figure 5; Figure 8 shows in detail the intermediate shaft 9 with the gear wheels \ and ^ on it and the disconnection K; and

Figure 9 shows in detail the reversing shaft 11 with the sharing gears t1 and t4 and the further coupling K2 thereon.

1S Detailed description of the drawings.

Figures 1,2 and 3 show a first embodiment of the drive 1 according to the invention. Figure 1 shows a schematic representation of the drive 1 shown in Figure 2 in side view. Figure 3 shows a practical layout of the drive 1. This drive 1 is present in a vehicle and has a drive source E, a continuously variable transmission T with an input shaft 3 which is coupled to the drive source E and an output shaft 5. with a first gear wheel t thereon, and a clutch C present between the drive source E and the input shaft 3 of the transmission T, for moving away from standstill, both forwards and backwards.

The output shaft 5 of the transmission T is coupled via a drive line I to a gearwheel 7 connected to a differential. The drive line I is for driving the vehicle during forward driving and has an intermediate shaft 9 which is present between the first gearwheel t, on the output shaft 5 and the gearwheel 7 connected to the differential. On the intermediate shaft 9 there is a second gearwheel which engages the first gearwheel t, and a third gearwheel t3 which engages with the gearwheel 7.

In order to be able to reverse, the drive line I can be interrupted by means of a disconnection K, and the drive is provided with a further drive line Π between the gearwheel 7 connected to the differential and the output shaft 5 of the transmission T. This further drive line II has a reverse shaft 11 present parallel to the intermediate shaft 9, with a reverse gear ζ, which engages with the gear 7 connected to the differential, and a fourth gear t4, which engages with the gear second gear t2. The further drive line Π can be interrupted by a further coupling K2.

Because the disconnection K1 and the further coupling K2 are form-locked, they can only be coupled to each other while the vehicle is stationary. This can be achieved by applying the wheel brake and opening the clutch C. For this purpose, the driver of the vehicle has to depress the brake pedal between shifting from reverse to forward or vice versa. Another possibility to operate the decoupling and further coupling is by including a brake B in the drive 1 which is energized during the shifting of the gear selector lever to the forward or reverse position. The brake B is preferably located between the clutch C and IS the transmission T, but can also be present between the transmission T on the one hand and the disconnection K, and the further clutch K2 on the other hand (shown in broken lines).

Figure 4 shows a slightly different practical layout of the drive shown in Figure 1. This figure speaks for itself again.

5,6 and 7 show a second embodiment of the drive 21 according to the invention. Figure 5 again shows a schematic representation of the drive 21 which is shown in Figure 6 in side view. Figure 7 again shows a practical layout of the drive 21. All parts that are the same as those of the first embodiment or that have the same function are indicated by the same reference numerals.

This drive 21 is very similar to that according to the first embodiment.

In this case, however, the second sprocket and the third sprocket tj can be directly coupled to each other by the uncoupling K instead of via the intermediate shaft 9 to interrupt drive line I for forward travel. The same applies to the reverse gear t1 and the fourth gear t4 which can be directly coupled to each other via the further coupling K2. In addition, the reverse gear wheel ta and the fourth gear wheel t4 are different in size in this embodiment. The brake B can be made very small so that it can be constructed within the clutch C.

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The operation of the first and second embodiments of the drive is as follows. In the neutral and parking position of the gear selector, K, closed and K2 are open (both not activated). When the gear selector is moved from the neutral or the parking position to the forward position, the crawl function is driven away via clutch C. At 5 accelerator pedal position zero, the crawl function is activated. When the gear selector is moved from the neutral or parking position to the reverse position, the brake B will first be applied to ensure that the vehicle is stationary. At standstill, K1 and K2 are activated and the brake B is released. As a result, the torque in the drive train will become zero, so that K, opens and K2 closes. Subsequently, reverse 10 can be driven away via coupling C. When the gear selector is moved from the reverse position to the forward position, the brake B will be activated under a certain vehicle speed (7.5 km / h) until the vehicle is stationary. At standstill, K1 and K2 are deactivated and the brake B is released. As a result, the torque in the drive train will become zero, so that K, closes and K2 opens. The C linkage can then be used to drive ahead. When the selector lever is moved from the forward position to the reverse position, the brake B will be applied under a certain vehicle speed (7.5 km / h) until the vehicle is stationary. At standstill, K1 and K2 are activated and the brake B is released. As a result, the torque in the drive train will become zero, so that K, opens and K2 closes. Subsequently, the C link can be used to drive backwards.

In Figures 8 and 9, the intermediate shaft 9, with the gears ^ and tj on it and the disconnection K, and the reverse shaft 11, with the reverse gear t, and the fourth gear t4 and the further clutch K2 on it the drive 21 in detail.

In figure 8 it is clear that the drive torque now passes through the decoupling K, and no longer through the intermediate shaft 9. As a result, the intermediate shaft 9 does not have to be provided with splines, as a result of which the intermediate shaft and the gears 1 and 3 can be made simpler. The axial forces act inwards with a right tooth with the gear 7 connected to the differential.

With the reversing shaft 11 shown in Figure 9, during forward travel (K2 open), the axial forces to the left act as a result of the occurring (lower) friction experienced by the reversing gear wheel ta and the fourth gear wheel t4. These gears then rotate in the opposite direction. If these gears were mounted in relation to each other, the maximum difference speed would be too large (15,000 rpm). To prevent this, the gear wheels are mounted separately from the fixed world, each having a radial and an axial bearing. The very small forces can be absorbed by small pivot bearings or plain bearings. When reversing (K2 closed), the axial forces also work to the left through the driving forces. Now, however, the occurring radial and axial forces 5 are much greater. By designing the axial bearing of the reverse gear wheel with a spring-loaded design (with a wave ring) and by incorporating a small axial play between the gear wheels, this axial bearing can be made much smaller. When reversing, the large axial force will cause the reversing sprocket ta and the fourth sprocket t4 to lie against each other, so that the greater part of this force comes on the left (large) axial bearing. With K2 closed, the reverse gear t4 and the fourth gear t4 turn in the same direction.

Although in the foregoing the invention has been elucidated with reference to the drawings, it should be noted that the invention is by no means limited to the embodiments shown in the drawings. The invention also extends to all embodiments deviating from the embodiments shown in the drawings within the scope defined by the claims.

1028799

Claims (7)

A drive (1; 21) comprising: - a drive source (E), - a continuously variable transmission (T) with an input shaft (3) coupled to the drive source and an output shaft (5) with a first thereon gear (t), - a clutch (C) between the drive source and the input shaft of the transmission or between the transmission and the first gear, and - a differential (D) which is connected to the output shaft via a drive line (I) of the transmission, which drive line comprises an intermediate shaft (9) with a second gear (tj) 10 in engagement with the first gear (t1) and a third gear (t3) in engagement with a differential gear (7), which intermediate shaft is present between the first gear on the output shaft and the differential, characterized in that - the drive line (I) can be interrupted by means of a disconnection (K1) which is present is between the second and third gear (t2, t3), and the drive for rts is provided with a further drive line (Π) between the differential and the output shaft of the transmission, which further drive line comprises a reverse shaft (11) parallel to the intermediate shaft with a reverse gear (tj, which engages with the gear (7) connected to the differential, and a fourth gear (t4), which can be coupled to the reverse gear (tj and engages the second gear (^), and which further drive line through a further coupling (K ^) can be interrupted, which is present between the reverse gear (tj and the fourth gear (t4). Drive (1; 21) according to claim 1, characterized in that the drive 25 further comprises a coupling mechanism which couples the differential (D) via the drive line (I) to the output shaft (5) of the transmission through the disconnection (K1) and / or connect the differential (D) via the further drive line (II) to the output shaft (5) of the transmission by closing the further coupling (K2). 3. Drive (I; 21) according to claim 1 or 2, characterized in that the disconnection (K1) directly couples the second and third gear (t ^ t3) on the intermediate shaft (9). Drive (1; 21) according to claim 1,2 or 3, characterized in that the 1028799 reversing gear (ta) and the fourth gear (t4) are mounted on the reversing shaft (11) and are directly connected to each other be linkable. Drive (1; 21) according to one of the preceding claims, characterized in that the coupling (C) is present between the drive source (E) and the transmission (T), 5 and between the coupling (C) and the the brake (B) is present in the differential gear (7). Drive (1; 21) according to claim 5, characterized in that the brake (B) is present between the clutch (C) and the transmission (T). 7. Drive (1; 21) according to claim 5 or 6, characterized in that the transmission (T) can only be coupled to the drive source (E) via the coupling (C). 1028799