JPH0116687B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a four-wheel drive system in which a horizontal engine is disposed at the front of a vehicle body.

(Prior Art) An example of a power transmission device for a horizontal front engine is disclosed in Japanese Utility Model Application No. 55-83119. In this disclosed device, a rear wheel power transmission system such as a bevel gear mechanism is added to a two-wheel drive system for front-wheel drive including a front differential of the engine, etc. to create a four-wheel drive system. .

(Problems to be Solved by the Present Invention) As described above, it is desirable to use common components between two-wheel drive and four-wheel drive.

For this purpose, the rear wheel drive parts necessary to configure the four-wheel drive system were made into a unit.
It is reasonable to add this to the two-wheel drive system and assemble it.

In order to meet this requirement, for example, components of the rear wheel drive system are housed in a transfer case to form a unit, and this transfer case is also integrated into a transmission case and a clutch housing that house two-wheel drive components. Among these, it has been proposed that the clutch housing be attached to the engine-side side adjacent to the clutch housing in the lateral direction of the vehicle body.

With such a configuration, the transmission case of a vehicle having at least a two-wheel drive power transmission system,
The clutch housing can be shared, but in this case the transfer case is placed at the rear of the engine, so interference between the two becomes a problem.

In other words, a bevel gear will be housed inside the transfer case, but since this bevel gear has the role of transmitting torque for driving the rear wheels, it is made to have a large diameter due to tooth width etc. There is a need. On the other hand, as mentioned above, from the viewpoint of common parts, the amount of longitudinal offset between the engine and the front differential is small, and if the bevel gear is placed coaxially with the front differential, interference with the engine may be a problem. becomes.

Further, there are also restrictions on the installation of the propeller shaft, particularly in the vertical position.

In other words, the positions of both axes of bevel gears are uniquely determined due to their meshing relationship, so once the axis position (height direction) of the input bevel gear (first bevel gear) is determined, the position of the axis of the input side bevel gear (first bevel gear) is determined. Since the axis position of the bevel gear (second bevel gear) is determined,
In a structure in which a bevel gear is arranged on the output shaft of the front differential, the position of the bevel gear is determined by the position of the front differential, and the degree of freedom in setting the output output portion of the transfer is reduced.

Therefore, in order to effectively standardize parts for two-wheel drive and four-wheel drive, it is necessary to fully consider the above circumstances.

(Means for solving the problem) The present invention was constructed in view of the above circumstances, and
In a drive system configured to share parts for 4-wheel drive and 2-wheel drive, the power transmission system should be free from interference with the engine, and there should be sufficient freedom in arranging the mechanism for extracting rear-wheel drive output. An object of the present invention is to provide a four-wheel drive device that can ensure high speed.

The features of the present invention that solve the above-mentioned problems include a horizontally mounted engine disposed at the front of the vehicle body, and a torque of the horizontally mounted engine is inputted through a clutch means,
A transmission mechanism arranged with its axial direction facing the lateral direction of the vehicle body, a front differential for driving the front wheels driven by the output gear of the transmission mechanism, and a front differential arranged coaxially with the front differential. a bevel gear mechanism driven by the output gear via a rear wheel drive gear mechanism;
and a rear wheel drive propeller shaft drivingly connected to the bevel gear mechanism, the rear wheel gear being disposed on the engine side of the clutch housing housing the clutch means and the front differential. A transfer case for accommodating the mechanism and the bevel gear mechanism is disposed, and at least a portion of the transfer case is attached to an end surface extending in the longitudinal direction of the vehicle body at the engine side side of the housing portion of the front differential of the clutch housing. A first axis coaxial with the front differential, a second axis parallel to the first axis, and a second axis perpendicular to these axes are provided in the transfer case. A rear wheel drive intermediate gear that has three axes, and has a rear wheel drive gear driven by the output gear on the first axis and meshes with the rear wheel drive gear on the second axis, and the intermediate gear. A first bevel gear driven by a gear is arranged, and a second bevel gear that meshes with the first bevel gear is arranged on the third axis, and at least the rear wheel drive gear and the rear wheel drive intermediate gear are arranged for the rear wheel drive. The gear mechanism is constructed by the first and second bevel gears.

According to the structure of the invention, the engine torque introduced into the transmission mechanism via the clutch means is transmitted on the one hand from the output gear of the transmission mechanism to the front differential.

Moreover, the above engine torque is, on the other hand,
The power is transmitted to the rear wheel drive gear located on the first axis extending in the lateral direction of the vehicle body, that is, coaxially with the front differential and the front wheel drive shaft, and is transmitted rearward via this rear wheel drive gear. be done.

In this case, preferably the rear wheel drive gear is
It is connected to the input gear of the differential through a cylindrical member that rotatably supports the front axle or the drive shaft of the front differential connected to the front axle. The engine power input to the rear wheel is transmitted to the rear wheel drive gear while being offset in the lateral direction of the vehicle body.

Furthermore, in the structure of the present invention, a rear wheel drive intermediate gear and a first bevel gear that mesh with the rear wheel drive gear are coaxially parallel to the first axis, that is, on a second axis extending in the lateral direction of the vehicle body. provided above.

This first bevel gear meshes with a second bevel gear disposed on a third axis perpendicular to the first and second axes.

The second bevel gear is connected to or integrated with the rear wheel propeller shaft.

Preferably, the meshing between the rear wheel drive gear and the rear wheel drive intermediate gear can be engaged/disconnected by an appropriate switching mechanism, thereby allowing switching between two-wheel drive and four-wheel drive. Can be done.

(Example) Hereinafter, an example of the present invention will be described based on the drawings. As shown in FIG. 1, a transmission 3 is connected to a horizontal engine 1 disposed at the front of a vehicle body (not shown) via a clutch 2 serving as a clutch means for controlling the transmission of torque from the engine 1. It is attached.

The clutch 2 includes a clutch accommodation chamber 8 for accommodating a clutch device 6 in a clutch housing 4, and a differential accommodation chamber 12 for accommodating a differential 10. The transmission 3 includes a transmission gear mechanism 16 and a transmission output gear 18 housed in a transmission case 14.

A differential drive gear 22 that is attached to the differential gear case 20 and meshes with the transmission output gear 18 is arranged in the differential housing chamber 12 . In this differential storage chamber 12, a first axis _l1 extending in the lateral direction of the vehicle body is set, and on this first axis _l1 , a differential 10 is disposed.
left and right differential output shafts 24,
26 and differential drive gear 22,
These rotation axes are arranged to coincide with the first axis _l1 . These differential output shafts 24 and 26 are connected to the left and right universal joints 2, respectively.
8, 30 to the left and right front wheel drive shafts 32, 3
4.

In the structure of this example, the differential 10 is
The differential output shafts 26 are located laterally offset a certain distance from the longitudinal center of the vehicle body, so that one differential output shaft 26 is longer than the other shaft.

A transfer case 38 that accommodates a bevel gear mechanism 40 for driving the rear wheels is disposed on the side of the differential housing chamber 12 of the clutch housing 4 on the vehicle body center axis 36 side, very close to the rear of the transverse engine 1. .

The transfer case 38 is provided with left and right through holes 52 and 54 in the side wall portion 48 through which the right differential output shaft 26 and a cylindrical member 50 that rotatably receives the right differential output shaft 26 are inserted, and in the rear wall portion 58. A rear through hole 60 is provided through which the wheel drive propeller shaft 56 is inserted. On the other hand, an output shaft through hole 59 through which the right differential output shaft 26 passes is provided on the engine side of the front differential 10 accommodating portion of the clutch housing 4, that is, on the vehicle body center axis 36 side. The peripheral edge of the output shaft through hole 59 of the clutch housing 4 and the peripheral edge of the left through hole 52 of the transfer case 38 are configured to have end surfaces 59a and 52a, respectively, extending in the longitudinal direction of the vehicle body.

The transfer case 38 has its left through hole 52.
is the output shaft through hole 5 of the clutch housing 4.
9, and both end surfaces 59a
and 52a are adapted to be combined.

In this assembled state, the transfer case is attached to the clutch housing 4 by tightening the bolts 105. Therefore, unlike the above-mentioned conventional example, the rear half of the differential housing chamber of the clutch housing 4 does not have to undergo a major structural change in order to attach the transfer housing.

The rotational axis of the cylindrical member 50 coincides with the first axis _l1 . The differential drive gear 22 is fixed to the cylindrical member 50, and is inserted through the output shaft insertion hole 59 of the clutch housing 4, and a rear wheel drive gear 61 is attached within the transfer case 38.

In this example, the second axis parallel to the first axis _l1 is
An axis l ₂ is set, and on this second axis l ₂ ,
The rear wheel drive gear shaft 62 is connected to its rotation shaft and the second
It is arranged so that the axis line _l2 coincides with that of the other.

A rear wheel drive gear shaft 62 is arranged to extend along the second axis _l2 , and the rear wheel drive gear 61 is attached to the rear wheel drive gear shaft 62 via a clutch mechanism 64. The rear wheel drive intermediate gear 66 is adapted to mesh with the rear wheel drive intermediate gear 66.

Further, in this example, a third axis l3 is set which is orthogonal to the first axis _l1 and the second axis _l2 , and on this third axis _l3 , the propeller shaft ₅₆ is arranged such that its rotation axis corresponds to the third axis l3. It is arranged to coincide with the third axis _l3 .

A first bevel gear 68 for rear wheel drive is further fixed to the gear shaft 62 for rear wheel drive, and the first bevel gear 68 for rear wheel drive is connected to the propeller shaft 56 for rear wheel drive.
The rear wheel drive second bevel gear 70 is integrated with the rear wheel drive second bevel gear 70.

As shown in FIG. 2, the clutch mechanism 64 can slide on a clutch gear 80, a synchronizer ring 82, a clutch output shaft gear 84, and the above three gears and rings provided on the rear wheel drive intermediate gear 66. It consists of a sleeve 86. sleeve 8
As shown in FIG. It is made to have a rocking motion in the center.

There is a recess 96 in the upper part of the yoke support shaft 94 and a spring 10 inserted into the clutch body 98.
0, the check ball 102 pressed against the yoke support shaft 94 falls into the recess 96.

The clutch mechanism 64 having the above configuration has the sleeve 8
6 is on the outer periphery of only the clutch output shaft gear 84, the rear wheel drive intermediate gear 66 and the rear wheel drive gear shaft 62 are not linked, and the rear wheels are not driven. On the other hand, when the operating arm 92 is operated manually or electrically, the switching yoke 90 swings, and the sleeve 8
6 is the clutch output shaft gear 84 and the clutch gear 80
When moving to the circumference of the rear wheel drive intermediate gear 6
6 and the rear wheel drive gear shaft 62 are rotated together to drive the rear wheels, resulting in four-wheel drive. Further, this state of the switching yoke 90 is maintained with a predetermined force by the action of the check ball 104.

(Effects of the Invention) According to the present invention, the transfer case is arranged on the side of the clutch housing on the engine side. Therefore, a power transmission device for four-wheel drive can be configured by using the drive device configured for two-wheel drive as is or by making simple changes. That is, parts other than the transfer case, which is a unitized part dedicated to driving the rear wheels, can be easily made common.

In addition, if a bevel gear is provided on the first shaft extending in the lateral direction of the vehicle body, and power is transmitted from this bevel gear to a propeller shaft extending in the longitudinal direction of the vehicle body, in order to achieve the desired power transmission function, the gear I have no choice but to increase the diameter.

However, the positional relationship between the first shaft and the engine is determined by the differential drive gear and the transmission output gear, so if the diameter of the bevel gear used for power transmission is increased, it will interfere with the engine. A problem arises.

In the structure of the present invention, since the second shaft is arranged parallel to the first shaft, the rear wheel drive gear provided on the first shaft for power transmission from the first shaft to the second shaft is a bevel gear. However, it is possible to configure the diameter to be relatively small.

Therefore, the above interference problem can be solved.

Further, by adopting a two-axis system, the second axis for extracting power for driving the rear wheels can be placed at any position around the first axis. Therefore,
Even if the positional relationship between the second and third axes is specified, the second
Since it is possible to obtain a degree of freedom in the arrangement of the entire combination of the shaft and the third shaft, the third shaft can be arranged freely as a result. In other words, the position from which the driving force for the rear wheels is taken out by the propeller shaft can be configured with sufficient consideration given to the layout within the engine room, which is advantageous in terms of freedom.

Furthermore, in the present invention, since the transfer case is placed on the side of the clutch housing so as to wrap with the clutch housing in the longitudinal direction of the vehicle body, the transfer case protrudes to the rear of the vehicle body by a small amount, making the entire device compact. can be obtained.

[Brief explanation of drawings]

FIG. 1 is a plan view including a partial cross section of a drive device according to an embodiment of the present invention, FIG. 2 is an enlarged view of a clutch mechanism,
Figure 3 is a sectional view taken along the line - in Figure 2;
The figure is a perspective view of the portion shown in FIG. 3. 1...Horizontal engine, 2...Clutch, 3...
...Transmission, 4...Clutch housing, 6...Clutch device, 8...Clutch accommodation chamber, 10...Differential, 12...Differential accommodation chamber, 14...Mission case, 16...Transformer Transmission gear mechanism, 18... Transmission output gear, 20... Differential gear case, 24, 26... Differential output shaft, 38... Transfer case, 4
0... Bevel gear mechanism, 52, 54... Side wall through hole, 64... Clutch mechanism.

Claims (1)

[Claims] 1. A transverse engine disposed at the front of the vehicle; a transmission mechanism to which the torque of the transverse engine is input via a clutch means; A front differential for front wheel drive driven by an output gear; a bevel gear mechanism driven by the output gear via a rear wheel drive gear mechanism coaxially arranged with the front differential; and the bevel gear mechanism. and a rear wheel drive propeller shaft drivingly connected to the rear wheel drive propeller shaft, wherein the rear wheel gear mechanism and bevel gear are provided on the engine side side of the clutch housing that accommodates the clutch means and the front differential. A transfer case for accommodating the mechanism is disposed, and at least a portion of the transfer case is aligned with an end surface extending in the longitudinal direction of the vehicle body at the engine side side of the housing portion of the front differential of the clutch housing. A first axis coaxial with the front differential, a second axis parallel to the first axis, and a third axis perpendicular to these axes are provided within the transfer case by bolts to the clutch housing. and set a rear wheel drive gear driven by the output gear on the first axis, and a rear wheel drive gear driven by the output gear on the first axis.
A rear wheel drive intermediate gear that meshes with the rear wheel drive gear and a first bevel gear driven by the intermediate gear are arranged on the axis, and a second bevel gear that meshes with the first bevel gear is arranged on the third axis. A four-wheel drive device characterized in that the rear wheel drive gear mechanism is configured by at least the rear wheel drive gear and the rear wheel drive intermediate gear, and the bevel gear mechanism is configured by the first and second bevel gears.