JPS62255237A - Torque distribution device for four-wheel drive car - Google Patents

Abstract

PURPOSE:To enhance the durability etc. and compact the construction through direct input of the torque into planetary gearing devices by connecting a plurality of differential gearing devices by a plurality of switching means selectively with possibility of torque transmission, and eliminating use of any clutching device. CONSTITUTION:A speed changer 1 is installed across in the front part of a car body, and in-the-cabin ends of a pair of front wheel accelerator shafts 2a, 2b, on the left and right, are coupled with a front differential 3. A drive gear 4 is loosely fitted on the shaft 2a on the left side of the car body and coupled with a rear shaft propeller shaft 7 through a driven gear 5 and a pair of bevel gears 6a, 6b. On said shaft 2a a plurality of planetary gearing devices 10, 11 are installed concentrical with the shaft 2a and in parallel to each their. A gear 17 of No.2 planetary gearing device 11 is coupled with said gear 4 through No.1 switching means 20, while a gear 6 of No.1 planetary gearing device 10 with the gear 4 through No.2 switching means 21.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a torque distribution device for a four-wheel drive vehicle that drives front wheels and rear wheels.

(Prior art) Conventionally, as a torque distribution device for this type of four-wheel drive vehicle,
For example, as disclosed in Japanese Utility Model Application Publication No. 56-122630, an additional clutch device such as a wet clutch or a fluid coupling is disposed on the transmission path of the drive torque transmitted from the transmission to the front and rear wheels. It is known that the clutch device is used to vary the drive l~silk distribution to the front and rear wheels.

(Problems to be Solved by the Invention) However, the above-mentioned clutch device generally transmits torque by the frictional force acting on the friction plate, and this PiIta
Since the drive torque distribution between the front and rear wheels is made variable by adjusting the magnitude of the force, the friction plates are prone to wear, and this wear is particularly severe in the so-called half-clutch state. For this reason, the conventional torque distribution device has a problem of lacking durability. In addition, since the frictional force acting on the friction plate is easily affected by external factors such as temperature, humidity, and vehicle vibration, there is also the problem that the distribution of drive torque between the front and rear wheels deviates from the set value. be.

The present invention has been made in view of the above, and its purpose is to provide an alternative to the above-mentioned clutch device, especially when the transmission is disposed horizontally at the rear of the front area of the vehicle body. The present invention aims to provide a torque distribution device that is compact, has excellent durability, and reliably distributes drive torque to the front and rear wheels according to a set value by using a plurality of planetary gear devices.

(Means for Solving the Problem) In order to achieve the above object, the present invention provides a torque distribution system for a four-wheel drive vehicle that selectively varies the distribution of drive torque from the transmission to the front and rear wheels. The device has the following configuration.

In other words, the above-mentioned transmission is disposed horizontally at the rear of the front area of the vehicle body, and a ring gear that directly meshes with the output gear of the transmission is mounted on the axle shaft of the wheel on the side where the transmission is installed. a plurality of planetary gear devices disposed in parallel, each distributing drive torque from the transmission at a different gear ratio, and a switching means for selectively connecting the plurality of planetary gear devices to enable torque transmission; The configuration is such that it is provided with:

(Function) With the above configuration, in the present invention, a plurality of planetary gear devices are selectively connected to each other so that torque can be transmitted by the switching means,
Gear A7 of the planetary gear device that can be connected to enable this torque transmission
Depending on the ratio, the distribution of drive torque from the transmission to the front and rear wheels is selectively varied.

In this case, since the planetary gear device transmits torque through meshing of gears, there is no problem of wear caused by frictional force as with the friction plates in conventional clutch devices. In addition, since the meshing of the gears mentioned above is hardly affected by external factors such as temperature or body photography, it is possible to reliably distribute the drive torque to the front and rear widths according to the set value. .

Moreover, the plurality of M-star vehicle devices mentioned above are arranged in parallel on the axle shaft of the wheel (front wheel or rear wheel) on the side where the transmission is installed, so that the arrangement space of the axle shaft can be effectively used and they can be integrated together. Therefore, the torque distribution device itself can be made more compact.

Furthermore, since the drive torque from the output gear of the transmission is directly input to the planetary gear device without going through a separate gear, the torque distribution device can be made more compact. .

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows a torque distribution device for a four-wheel drive vehicle according to a first embodiment of the present invention, 1 is a transmission, and the transmission 1 includes:
The engine (not shown) is installed horizontally at the front of the vehicle body. Reference numerals 2aJ3 and 2b denote a pair of left and right front wheel axle shafts located near the transmission 1. The inner end of each axle shaft 28.2b is connected to the front differential 3, and the outer end of each axle shaft 28.2b is connected to the front differential 3. (
(not shown).

, E A drive gear 4 is loosely fitted onto the axle shaft 2a on the left side of the vehicle body, and the drive gear 4 connects to the propeller shaft for the rear wheels via a driven gear 5 and a pair of bevel gears 6a and 6b. 7 is drivingly connected to the front end of 7. Although not shown, the rear end of the propeller shaft 7 is drivingly connected to left and right rear wheels via a rear differential, an axle shaft, or the like.

Furthermore, on the axle shaft 2a on the left side of the vehicle body, between the drive gear 4 and the front differential 3, a first M star gear device 10 and a second planetary gear device 11 are coaxial with the axle shaft 2a and parallel to each other. It is located in The first and second planetary gear systems aio, 1
i is a pair of inner and outer planetary gears 14a, 14b or 1, both of which are double planetary gears, and which are connected to the front differential 3 via carriers 12 or 13, respectively;
5a, 15b, and the inner planetary gear 14a or 1
5a, and a ring gear 1 that meshes with the outer planetary gear 14b or 15b.
8.19. The above two-way star gear device 10.1
The No. 1 ring gears '18 and 19 are integrally molded together, and a gear portion 18a that directly meshes with the output gear 8 of the speed change Ia1 is formed on the outer periphery of the ring gear 18 of the No. 11i star gear device 10.

Furthermore, 20 is the sun gear 1 of the second planetary gear device 11.
7 and drive gear 4; ! The first and second switching means 20 and 21 are both comprised of wet clutches, and are connected to the axle shaft 2a on the left side of the vehicle body.
They are arranged in parallel at a position on the outer side of the vehicle (closer to the left front wheel) than the upper drive gear 4, and can selectively transmit torque to the first and second planetary gear units 10 and 11 to the drive gear 4 respectively. It is supposed to connect.

Next, to explain the operation of the first embodiment, the first
In the selected state, when the first switching means 20 is connected and the second switching means 21 is disconnected, two planetary gear devices 10.
11, only the second planetary gear unit 2?11 transmits the driving torque and operates the torque distribution, and the first planetary gear unit 1
0 is a free state (idle rotation state). That is, the driving torque output from the output key V8 of the transmission 1 is directly transmitted to the ring gear 19 side of the second planetary gear unit 11 which is integrated with the ring gear 18 at the gear portion 18a of the ring gear 18 of the first planetary gear unit 10. Enter the corresponding 2nd M star tooth! Xi device 11
The rotation angle is distributed according to the ratio of the rotation angle of the sun gear 17 and the rotation angle of the carrier 13 per rotation of the ring gear 19. The drive torque distributed to the ring gear 17 is transmitted from the drive gear 4 to the rear wheel side via the propeller shaft 7 via the first switching means 20, while the drive torque distributed to the brake gears 15a, 15b or the carrier 13 is transmitted to the rear wheels via the propeller shaft 7. Torque is transmitted to the front wheels via the front differential 3 and axle shafts 2a, 2b.

Also, as a second selection state, the first switching means 20 is disconnected,
When the second disconnection means 21 is connected, only the first planetary gear set 10 operates to transmit the driving torque and distribute the torque, contrary to the case of the first selection state described above, and the second planetary gear set 11 becomes free. That is, the driving torque from the output gear 8 of the transmission 1 is directly input to the ring gear 18 side of the first planetary gear device 10, and
0, the rotation angle is distributed in accordance with the ratio of the rotation angle of the ring gear 16 to the rotation angle of the carrier 12 per rotation of the ring gear 18. The drive torque distributed to the sun gear 16 is transmitted from the drive gear 4 to the rear wheel side via the propeller shaft 7 via the second switching means 21.
The driving torque distributed to the planetary gears 14a, 14b or the carrier 12 is transmitted to the front differential 3.
and is transmitted to the front wheels via axle shafts 2a, 2b.

Further, as a third selection state, the first and second switching means 2
If 0.21 are connected together, the first and second ¥1
Since the star gear units io and ii are locked together and do not perform torque distribution, the drive torque from the output gear 8 of the transmission 1 is normally distributed equally to the front and rear wheels. communicated. Further, when either the front wheel or the rear wheel is no longer generating driving resistance due to derailment or the like, the driving torque is transmitted only to the other wheel.

Here, the gear ratio of the first planetary gear device 10 (the ratio of the rotation angle of the sun gear 16 to the rotation angle of the carrier 12 per one rotation of the ring gear 18) and the gear ratio of the second planetary gear device 11 (the ratio of the rotation angle of the sun gear 16 per one rotation of the ring gear 18) The ratio of the rotation angle of the sun gear 17 to the rotation angle of the carrier 13 per rotation is different from each other. For example, if the gear ratio of the first planetary gear device 10 is 60
The gear ratio of the second planetary gear unit 11 is set to 50 to 40.
If the ratio is set to 50:50, the distribution of drive torque to the front and rear wheels will be 50:50 in the first selection state, 40:60 in the second selection state, and 40:60 in the third selection state. In the case of the state, the ratio is 50:50 in the locked state.

Therefore, in the torque distribution device as described above, the first and second planetary gears Mfi10 that operate the torque distribution
．． 11 transmits torque through the meshing of gears, so there is no problem of wear caused by frictional force as with friction plates in conventional clutch devices. In addition, since the meshing of the gears described above is not affected by external factors such as temperature and vehicle body vibration, the distribution of drive torque to the front and rear wheels is adjusted to the set value (each M star gear unit 10
．． 11 gear ratio). still,
A wet clutch is used as the first and second switching means 20.21, but this switching means 20.21 simply switches connection/disconnection of torque transmission, and does not enter a so-called clutch state. Since there is no friction plate, wear on the friction plate does not pose a particular problem.

Moreover, the first and second freewheel gear units 10 and 11 are disposed coaxially and in parallel on the front wheel axle shaft 2a, so that the arrangement space of the axle shaft 2a can be effectively utilized and consolidated. Therefore, it is possible to effectively downsize the torque distribution device itself. Furthermore, since the driving torque from the output gear 8 of the transmission 1 is directly input to the planetary gear devices io and i1 without going through a separate gear, the torque distribution device can be made even more compact. be able to.

FIG. 2 shows a torque distribution device for a four-wheel drive vehicle according to a second embodiment of the present invention. In this torque distribution device, two ! ! The first planetary gear unit 31 of the two-star gear unit
is a pair of inner and outer planetary gears 33 which are made of double planetary gears and are connected to the drive gear 4 via a carrier 32.
a, 33b, a sun gear 34 that meshes with the inner platenelli gear 33a, and the outer platenelli gear 33b.
The ring gear 35 has a gear portion 35a formed on its outer periphery to directly mesh with the output gear 8 of the transmission 1. On the other hand, the 2 mm star gear device 36 is composed of a simple planetary gear, and includes a planetary gear 37 connected to the ring gear 35 of the first planetary gear device 35, a sun gear 738 that meshes with the planetary gear 37, and a planetary gear 738 that meshes with the planetary gear 37 and drives the planetary gear 37. The ring gear 39 is connected to the gear 4.

The sun gear 38 of the second planetary gear unit 36 is connected to the sun gear 34 of the eleventh planetary gear unit 31 via the first switching means 20.
are respectively connected to the front differential 3 via second switching means 21, and the first and second switching means 20.21 are connected to the 2'f1 star gear device 36 on the axle shaft 2a and the front differential 3. are arranged in parallel between. The rest of the configuration of the torque distribution device is the same as in the first embodiment, and the same members are given the same reference numerals and their explanations will be omitted.

Also in the case of the second embodiment, as in the case of the first embodiment, the first and second exchange means 20.2
By switching the connection/disconnection in step 1, the distribution of drive torque to the front and rear wheels can be selectively switched to three stages, and a similar effect can be obtained.

In this case, the distribution of the driving torque in the second planetary FG wheel device 36 is determined in accordance with the ratio of the number of teeth (gear ratio) between the sun gear 38 and the ring gear 39.

Further, FIG. 3 shows a torque distribution device for a four-wheel drive vehicle according to a third embodiment of the present invention, and in this torque distribution device, the 1T1 star gear device 4 is
1 is constituted by a simple planetary gear, and a second planetary gear device 4
5 is composed of a double planetary gear. That is, the second planetary gear device 45 has a pair of inner and outer planetary gears 47a and 47b connected to the front differential 3 via a carrier 46, a sun gear 48 that meshes with the inner planetary gear 47a, and a sun gear 48 that meshes with the outer planetary gear 47b. , and a ring gear 49 in which a gear portion 49a that directly meshes with the output gear 8 of the transmission 1 is formed on the outer periphery.

On the other hand, the first planetary gear device 41 includes a planetary gear 42 connected to the ring gear 1749 of the second planetary gear device 45, and a sun gear A243 that meshes with the planetary gear 42 and is connected to the front differential 3.
and a ring gear 44 that meshes with the planetary gear 42.
It is equipped with

The sun gear 48 of the second 't1 star gear unit 45 is connected to the drive gear 4 via the first switching gear 20, and the ring gear 44 of the first planetary gear unit 41 is connected to the drive gear 4 via the second switching means 21. , the first and second switch #3
120.21 are arranged on both sides of the axle shirt 1-2a with the drive gear 4 in between. In addition, the first
And the second planetary gear set? ff41.45 are mutually locked by a lock clutch 50.

In the case of the third embodiment, the lock clutch 5 locks the first and second planetary gear units 41, 45 to each other.
0 are provided separately, the drive torque distribution by switching the first and second switching means 20.21 on and off can be switched to only two stages. That is, when the first switching means 20 is connected and the second switching means 21 is disconnected, the second switching means 20 is connected and the second switching means 21 is disconnected.
The distribution of drive torque to the front and rear wheels is determined by the gear ratio of the one-star gear device 45 (the ratio of the rotation angle of the sun gear 48 to the rotation angle of the carrier 46 per one rotation of the ring gear 49). When disconnected and the second switching means 21 is connected, the gear ratio of the first planetary gear device 41 (single A
143 and ring gear A744)
-The distribution of the cost is determined.

It should be noted that the present invention is not limited to the first to third embodiments described above, but includes various other modifications. For example, in each of the above embodiments, two planetary gear devices 10 (31 or 41), 1
1 (36 or 45) are arranged in parallel, and the distribution of drive torque to the front and rear wheels is selectively switched between three stages.
Three or more yli star gear devices are arranged in parallel on the top, and the front and
The configuration may be such that the distribution of the drive torque to the rear wheels can be selectively switched to a plurality of stages.

In addition, as a switching means for selectively connecting the differential gear device to enable torque transmission, in addition to using the 0-type clutch as in the embodiment, various other devices for switching between connecting and disconnecting, such as a dog clutch and an electromagnetic clutch, are used. It's okay.

Further, in each of the above embodiments, the present invention is applied to the case where the transmission 1 is placed horizontally at the front of the vehicle body, but it is also applicable to the case where the transmission is placed horizontally at the rear of the vehicle body. can. In this case, multiple planetary teeth? T! The @ positions may be arranged in parallel on the rear wheel axle shaft.

(Effects of the Invention) As described above, according to the torque distribution device for a four-wheel drive vehicle according to the present invention, the plurality of planetary teeth *tii are selectively connected to enable torque transmission by the switching means, and the plurality of planetary teeth *tii are connected to enable torque transmission. Since the configuration is such that the distribution of drive torque from the transmission to the front and rear wheels can be selectively varied by the gear ratio of the planetary gear system, the I! ! Wear caused by friction does not become a problem, and durability can be improved.Also, it is hardly affected by external factors, and torque distribution can be accurately performed according to the set value. .

Moreover, the plurality of planetary gear devices described above are arranged in parallel on the front wheel or rear wheel axle shaft on the side where the transmission is installed, and are configured to directly receive the driving torque from the output gear of the transmission. Therefore, it is possible to effectively downsize the torque distribution device itself.

[Brief explanation of drawings]

The drawings relate to embodiments of the present invention, and FIG. 1 is a schematic diagram showing the overall configuration of a torque distribution device for a four-wheel drive vehicle according to the first embodiment, and FIGS. 2 and 3 are diagrams, respectively. FIG. 1 is a diagram corresponding to FIG. 1 according to a second embodiment and a third embodiment. 1...Shift line, 2a...Axle shaft, 8...
・Output gear, 10.31.41...First planetary gear II device, 11.36.45...Second planetary gear IA position, 18
, 35.49... Ring gear, 20... First switching means, 21... Second switching means. + (-f-1 Patent Applicant: Mazda Motor Corporation (nee. 1,.°“ Agent 1)
Hiroshi, -1. Figure 1 Figure 2

Claims (1)

[Claims] (1) A torque distribution device for a four-wheel drive vehicle that selectively varies the distribution of drive torque from a transmission to front and rear wheels, wherein the transmission is disposed horizontally in the front area of the vehicle body and in the rear. On the axle shaft of the wheel on the side where the transmission is installed, there is a ring gear that directly meshes with the output gear of the transmission, and a plurality of planetary planets that distribute the drive torque from the transmission at different gear ratios. 4. Gear devices are arranged in parallel, and switching means is provided for selectively connecting the plurality of planetary gear devices so that torque can be transmitted.
Torque distribution device for wheel drive vehicles.