JPS635293B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a four-wheel drive vehicle equipped with a so-called horizontal engine whose crankshaft extends in the left-right direction of the vehicle body.

Generally, in a four-wheel drive vehicle, the engine is arranged so that its crankshaft extends in the longitudinal direction of the vehicle body, and the transmission is arranged so that its input shaft and output shaft extend in the longitudinal direction of the vehicle body. A transfer is added to the front wheel propeller shaft and the rear wheel propeller shaft divides the engine's driving force into two and transmits it to the front differential and rear differential, driving the four wheels on the front, rear, left and right sides. It has been known.

Four-wheel drive vehicles equipped with such vertically mounted engines have the problem of not being able to provide a large cabin space, so in recent years, four-wheel drive vehicles equipped with horizontally mounted engines that do not have this problem have been introduced. Some suggestions have been made. For example, JP-A-57-
As shown in Publication No. 41216, the drive system can be constructed with a relatively simple structure by arranging a center differential consisting of a group of planetary gears with a differential function coaxially with the front differential on the output side of the transmission. There is a compact 4-wheel drive vehicle.

However, in the device disclosed in JP-A No. 57-41216, one of the pair of bevel gears for transmitting power to the rear wheels is provided coaxially with the center differential and also located close to the center differential. Therefore, the position of this bevel gear in the left-right direction of the car body is limited by the installation position of the center differential, and the degree of freedom is low.
It becomes a hindrance to the layout. Further, since the center differential and the input gear to the center differential are arranged in parallel in the axial direction, the length in the axial direction becomes longer, which is disadvantageous in terms of compactness.

By the way, in order to increase the degree of freedom in the layout, it is conceivable to arrange the bevel gear on a different axis from the center differential, as shown in, for example, Japanese Unexamined Patent Publication No. 56-154328. however,
In order to make the above-mentioned bevel gear a separate shaft from the center differential, another gear is required, and when this other gear is added to a four-wheel drive vehicle such as the one disclosed in Japanese Patent Application Laid-open No. 57-41216, it becomes the input gear mentioned above. In addition, the axial length becomes longer due to this additional gear, which is extremely disadvantageous in terms of compactness.

The present invention has been made in view of the above points, and includes 4
In a wheel drive vehicle, it is an object of the present invention to increase the degree of freedom in selecting the positional relationship between a pair of bevel gears that transmit driving force to the rear wheels while suppressing the increase in the length in the axial direction.

The present invention includes an engine arranged such that a crankshaft extends in the left-right direction of the vehicle body, a transmission in which an input shaft and an output shaft having a drive gear are arranged in the left-right direction of the vehicle body, and a planetary gear group. The center differential includes a center differential and a front differential composed of a group of bevel gears disposed close to the side of the center differential on the engine side, the center differential and the front differential are coaxially arranged side by side, and the center differential is arranged side by side on the engine side. The planetary gear group includes a ring gear on the outer periphery of which is formed an input gear that meshes with and drives the drive gear of the output shaft of the transmission, and a planetary pinion that is supported by a pinion carrier and meshes with the ring gear. and a sun gear that meshes with the planetary pinion, and these ring gear, planetary pinion, and sun gear are arranged so that their meshing points are on the same plane as the meshing points of the drive gear and input gear, and the pinion carrier is The driving force is transmitted to the front differential case, and the sun gear is connected to a pair of gears via a gear disposed close to the side opposite to the front differential of the sun gear and a gear fixed to an offset shaft that meshes with this gear. It is characterized by transmitting driving force to the rear wheel drive shaft using a bevel gear.

That is, in the present invention, the center differential composed of a group of planetary gears is arranged such that the meshing points of the ring gear, planetary pinion, and sun gear are on the same plane as the meshing points of the drive gear and the input gear, In addition to eliminating the increase in the axial length of the input gear to the center differential, the above-mentioned objective is achieved by providing the gear for driving the offset shaft in the free space.

Embodiments of the present invention will be described below with reference to the drawings.

Embodiment 1 In FIGS. 1 and 2, reference numeral 1 denotes an engine, which is arranged at the front of the vehicle body so that a crankshaft 2 extends in the left-right direction of the vehicle body. Reference numeral 3 denotes a transmission, which is disposed within a casing 4 and has an input shaft 6 connected to the crankshaft 2 via a clutch means 5, and an output shaft 8 linked to a center differential 7, which are arranged in the left-right direction of the vehicle body. It is located.

The input shaft 6 is provided with a first speed gear 9, a reverse gear 10, and a second speed gear 1 from the clutch means 5 side.
1, a third speed gear 12 and a fourth speed gear 13 are fixedly installed in this order. On the other hand, the output shaft 8 includes gears 14, 15, 16, 17, 18 that mesh with the gears 9, 10, 11, 12, 13, and a drive gear 1.
9 is fixedly installed, and gears 14, 15, 17
Synchronizing mechanisms 20 and 21 are arranged between and 18.

The center differential 7 includes a ring gear 22 on the outer periphery of which is formed an input gear 22a that meshes with and drives the drive gear 19 of the output shaft 8 of the transmission 3, and a planetary gear that is supported by a pinion carrier 23 and meshes with the ring gear 22. pinion 24
and a sun gear 25 that meshes with the planetary pinion 24. The planetary pinion 24 is a double pinion type composed of a pair of pinions 26 and 27 that mesh with each other, and one pinion 26 is connected to the ring gear 22.
The other pinion 27 is in mesh with the sun gear 25, respectively. The ring gear 22, planetary pinion 24, and sun gear 25 have respective meshing points that are similar to the drive gear 19 and the input gear 2.
It is arranged so as to be on the same plane as the engagement point of 2a.

The front differential 28 is disposed close to the side of the center differential 7 on the engine 1 side, and within the front differential case 29 of the front differential 28, a pair of bevel gears 31 are disposed opposite to each other by a short axis 30 in the longitudinal direction of the vehicle body. 32, and the pair of bevel gears 31, 32
It is constituted by a bevel gear group consisting of another pair of bevel gears 33 and 34 which are disposed opposite to each other on the left and right so as to mesh with each other.

Shafts 35, 36 of a pair of left and right bevel gears 33, 34
One ends of front wheel drive shafts 39 and 40 are connected to the outer ends of the drive shafts 39 and 40 via joints 37 and 38, respectively.
The other ends of the wheels 9 and 40 are connected to left and right front wheels 43 and 44 via other joints 41 and 42, respectively.

The front differential case 29 is the center differential case 7.
A supporting member is configured integrally with the pinion carrier 23 so that the driving force is transmitted thereto, and is connected and fixed to the ring gear 22 of the center differential 7 via bearings 45 and 46 at both ends of the outer periphery, and covers the front differential case 29. 47 so as to be rotatable.

A differential sleeve 48 is spline-fitted to the end of the front differential case 29 on the opposite side from the center differential 7. This differential sleeve 48 is connected to a gear 49 fixed to the shaft 36 of the bevel gear 34.
It is designed to be moved in the axial direction between an engaged position in which it meshes with the gear 49 and a non-engaged position in which it does not mesh with the gear 49 but only engages with the front differential case 29 by an operating means (not shown). When set to the engagement position, the center differential 7 is fixed and immobile, and for example, when one wheel is idling on rough ground such as a muddy road, driving force is prevented from escaping through the idling wheel. As a result, appropriate driving force can be distributed to all wheels.

50 is the shaft 35 of the left and right bevel gears 33, 34;
36, and one end thereof is a transmission gear that is meshed and driven by a drive gear 51 that is disposed close to the opposite side of the front differential 28 of the sun gear 25 of the center differential 7 and is connected to the sun gear 25. 52 is integrally molded, while a bevel gear 53 is provided at the other end.
is fitted and fixed.

This bevel gear 53 is connected to another bevel gear 5 provided at the front end of the propeller shaft 54 via a joint 55.
6 is engaged. These pair of bevel gears 53,
At 56, driving force is transmitted to rear wheel drive shafts 57 and 58.

A bevel gear 61 of a rear differential 60 is connected to the rear end of the propeller shaft 54 via a joint 59. A large bevel gear 64 that supports a pair of bevel gears 62 and 63 meshes with this bevel gear 61, and another pair of bevel gears 65 and 66 on the left and right sides mesh with the bevel gears 62 and 63. They are placed opposite each other.

The left and right bevel gears 65 and 66 have joints 6
One ends of rear wheel drive shafts 57, 58 are connected via joints 69, 70, and left and right rear wheels 71, 72 are connected to the other ends of the drive shafts 57, 58 via joints 69, 70, respectively.

With the above configuration, the driving force output from the engine 1 is inputted to the input shaft 6 of the transmission 3 via the clutch means 5, and the gear is changed as appropriate, and the driving force is transferred to the center differential from the drive gear 19 of the output shaft 8. It is output to the ring gear 22 of No. 7.

The driving force input to the ring gear 22 is divided between a pinion carrier 23 that supports a planetary pinion 24 and a sun gear 25. Center differential 7 functions as a differential device, and front differential 2
Pinion carrier 23 and rear differential 6 that drive 8
The rotational speed difference between the rotational speed and the sun gear 25 that drives 0 can be absorbed and alleviated.

Therefore, the driving force dividedly transmitted to the pinion carrier 23 is transmitted to the short shaft 3 of the front differential case 29.
0, and is distributed to the left and right by a pair of bevel gears 31 and 32 supported by the short shaft 30 and another pair of bevel gears 33 and 34 meshing with these, thereby causing left and right front wheels 43, 44 is driven.

On the other hand, the driving force dividedly transmitted to the sun gear 25 rotationally drives the transmission gear 52 and therefore the shaft 50 via the driving gear 51 which is integrated with the sun gear 25. Due to the meshing of the bevel gear 53 fixed to the shaft 50 and another bevel gear 56, the signal is transmitted to the rear differential 60 via the propeller shaft 54, and is distributed to the left and right to drive the left and right rear wheels 71, 72.

Embodiment 2 This example is a case in which a transmission which is a main transmission is equipped with an auxiliary transmission.

In Fig. 3, the ring gear 2 of the center differential 7
2 meshes with a gear 83 formed integrally with a shaft 82 constituting a sub-transmission 81;
A low speed gear 84 and a high speed gear 85 are fitted and fixed in order from the 3 side, and a synchronization mechanism 86 is interposed between the two gears 84 and 85.

Gears 87 and 88 that mesh with the low speed gear 84 and high speed gear 85 are integrally formed on the output shaft 8a of the transmission 3. As a result, the main transmission changes the speed into four stages in each of the two stages of high speed and low speed, resulting in a total of eight stages.

Further, the shaft 50 having the transmission gear 52 and the bevel gear 53 is divided into a first shaft 50a having the transmission gear 52 and a second shaft 50b having the bevel gear 53,
Both shafts 50a and 50b are rotatably connected by a bearing 89. A 2-4 switching sleeve 90 is movably spline-fitted to the connecting portion between the first shaft 50a and the second shaft 50b, and the two shafts 50a and 50b are connected and rotated synchronously in a four-wheel drive position and in a first position. Axis 5
It moves between the two-wheel drive position where the spline is fitted only to 0a. Note that in the two-wheel drive position, the rear differential 60 and both rear wheels 71, 72 are disconnected.

Since the other components are the same as those in Example 1, the same reference numerals are used for the similar components, and detailed explanation thereof will be omitted.

In the above embodiment, the case where the engine 1 is disposed at the front of the vehicle body has been described, but it goes without saying that the present invention can also be applied to a case where the engine is disposed at the rear of the vehicle body.

As described above, in the present invention, the center differential is configured with a planetary gear group, and the meshing points of the ring gear, planetary pinion, and sun gear are formed on the outer periphery of the drive gear and the ring gear of the output shaft of the transmission. At the same time, the sun gear of the center differential is arranged so as to be flush with the meshing point with the input gear, and the sun gear of the center differential is meshed with and offset from a gear located close to the side opposite to the front differential of the sun gear. Drive power is transmitted to the rear wheel drive shaft by a pair of bevel gears via a gear fixed to the shaft, which suppresses the increase in length in the left-right direction (axial direction) of the vehicle and increases drive power to the rear wheels. It is possible to increase the degree of freedom in selecting the positional relationship between the pair of bevel gears that transmit force.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is a diagram schematically showing the drive system of Embodiment 1 in skeleton form, and FIG. 2 is a diagram specifically showing the main parts of Embodiment 1. , FIG. 3 is a diagram similar to FIG. 2 of the second embodiment. DESCRIPTION OF SYMBOLS 1... Engine, 2... Crankshaft, 3... Transmission, 6... Input shaft, 7... Center differential, 8, 8a... Output shaft, 22... Ring gear, 22a... Input gear, 23... ...Pinion carrier, 24...Planetary pinion, 25...Sun gear, 28...Front differential, 29...Front differential case, 39, 40...Front wheel drive shaft, 48
...Defroc sleeve, 50...Shaft, 52...
Transmission gear, 57, 58... Rear wheel drive shaft, 81...
Sub-transmission, 90...2-4 switching sleeve.

Claims (1)

[Claims] 1. An engine arranged so that the crankshaft extends in the left-right direction of the vehicle body, a transmission in which an input shaft and an output shaft having a drive gear are arranged in the left-right direction of the vehicle body, and a planetary gear group. and a front differential made up of a group of bevel gears disposed close to the side of the center differential on the engine side, the center differential and the front differential being coaxially arranged side by side, The planetary gear group that constitutes the center differential includes a ring gear on the outer periphery of which is formed an input gear that meshes with and drives the drive gear of the output shaft of the transmission, and a planetary gear that is supported by a pinion carrier and meshes with the ring gear. It consists of a pinion and a sun gear that meshes with the planetary pinion, and these ring gears,
The planetary pinion and the sun gear are arranged such that their meshing points are flush with the meshing points of the drive gear and the input gear, the pinion carrier transmits driving force to the front differential case, and the sun gear transmits the driving force to the front differential case. A pair of bevel gears transmits driving force to the rear wheel drive shaft through a gear disposed close to the side opposite to the front differential of the sun gear and a gear fixed to an offset shaft meshing with this gear. A four-wheel drive vehicle featuring 2. The four-wheel drive vehicle according to claim 1, wherein the ring gear is rotatably supported at both ends of the outer periphery of the front differential case. 3. The four-wheel drive vehicle according to claim 1 or 2, wherein the planetary pinion is a double pinion type composed of a pair of pinions.