JPH058645A - Case structure for power train - Google Patents

Abstract

PURPOSE:To provide a power train which is compact and allows a case to be easily assembled in a four-wheeled vehicle wherein an engine and a speed change gear are placed horizontally in parallel. CONSTITUTION:An engine 6, a speed change gear 7, a case 70 for a front differential and power transmission gear devices are integrally constituted. The axis supporting face of a crank shaft 8 and the I/O axis 22 of a speed change gear 7 or the supporting axis portion of a front wheel drive axel 42R are provided on the same mating face F1 and the axis supporting portion of a gear drive shaft 46 in the power transmission gear device is provided on the mating face F2 of the case 70, which is different from the mating face F1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a case structure for a power train, which is mounted on a four-wheel drive vehicle and includes an engine and a transmission.

[0002]

2. Description of the Related Art Conventionally, in a vehicle such as a four-wheel drive vehicle or an FF (front engine / front drive) type vehicle, when arranging an engine and a transmission in an engine room in the front of the vehicle body, these are installed vertically. There are various modes depending on whether the device is mounted horizontally or horizontally. Of these, especially
When both the engine and the transmission are horizontally arranged, if both of them are arranged in series, there is a problem that the axial length of the entire power train becomes considerably long. Therefore, for example, Japanese Patent Laid-Open No. 63-103735 and Japanese Patent Laid-Open No. 1-33
As disclosed in Japanese Patent No. 16560, etc., a transmission has been developed in which a transmission is arranged in parallel in front of or behind an engine, and both of them are connected by a power transmission means such as a gear or a chain so that power transmission is possible. Has been put to practical use.

On the other hand, in an FF type vehicle or an FR (front engine / rear drive) type vehicle, from the viewpoint of downsizing the entire power train, for example
As disclosed in Japanese Unexamined Patent Publication No. 22886, a crankcase of an engine and a case for accommodating a transmission and a front differential are formed into an integral structure, while a shaft support portion of a crankshaft of an engine and a drive axle of a transmission shaft or a front wheel. It is known to provide the same on a mating surface.

[0004]

However, in the case of a four-wheel drive vehicle, in the power train, in addition to the power transmission system that transmits the driving force output from the transmission to the front wheels, the above driving force is transmitted to the propeller shaft. A power transmission gear device for transmission is also provided in the engine room, but there is no one in which the case of the entire power train including this power transmission gear device is integrated. Further, in order to integrally structure the case of the entire power train, it is required from the viewpoint of assembling that the shaft support portion of the gear drive shaft extending in the vehicle width direction of the power transmission gear device is provided on the mating surface. If this mating surface is provided so as to intersect with the mating surface of the shaft support portion of the crankshaft, the three cases must be aligned and coupled to each other, and the assembling work becomes troublesome.

The present invention has been made in view of the above points, and an object of the present invention is particularly excellent in assemblability by appropriately setting the position of the mating surface of the shaft supporting portion of the gear drive shaft. It is intended to provide a powertrain case structure.

[0006]

In order to achieve the above object, the invention according to claim 1 is such that an engine is disposed horizontally in a front room of a vehicle body with its crankshaft oriented in the vehicle width direction. In addition, the transmission is arranged in parallel with the engine behind the engine, and the drive axle of the front wheels and the axial center of the front differential located coaxially with the drive axle are located in the rear of the vehicle body with respect to the crankshaft of the engine. It is arranged, behind this axis,
The target is a four-wheel drive vehicle in which a gear drive shaft of a power transmission gear device that transmits a driving force from a transmission side to a propeller shaft extends in the vehicle width direction. Then, the case of the engine, the transmission, the front differential, and the power transmission gear device is formed as an integral structure, and the shaft support portion of the crankshaft and the support shaft portion of the transmission shaft or the front wheel drive axle with respect to the case are formed. , And the shaft support portion of the gear drive shaft of the power transmission gear device is provided on a mating surface of a case different from the mating surface.

According to a second aspect of the present invention, the engine according to the first aspect is arranged, the engine is arranged horizontally with its upper side inclined rearward, and the shaft support portions of the crankshaft are aligned. The mating surface of the shaft support portion of the gear drive shaft is provided above the rear end position of the surface.

A third aspect of the invention is dependent on the second aspect of the invention, wherein a center differential that allows a rotation difference between the front wheels and the rear wheels is provided coaxially with the shaft of the transmission. To do.

According to a fourth aspect of the present invention, the engine according to the first aspect is arranged, the engine is horizontally arranged with its upper side inclined forward, and the crankshaft shaft support is aligned. The mating surface of the shaft support portion of the gear drive shaft is provided below the rear end position of the surface.

A fifth aspect of the invention is dependent on the fourth aspect of the invention, and is configured such that a center differential that allows a rotation difference between the front wheels and the rear wheels is provided on the front wheel drive axle.

A sixth aspect of the present invention is directed to the same four-wheel drive vehicle as the first aspect of the invention, and the case of the engine, the transmission, the front differential, and the power transmission gear device is formed as an integrated structure, The shaft supporting portion of the crankshaft and the shaft supporting portion of the transmission or the front wheel drive axle for the case are provided on the same mating surface, and the shaft supporting portion of the gear drive shaft of the power transmission gear device is also on the same mating surface. It is configured to be installed in.

The invention according to claim 7 is dependent on the invention according to claim 6, wherein the engine is horizontally arranged with its upper side inclined rearward, and the axis of the propeller shaft is arranged as described above. The power transmission gear device is configured to be offset above the center of the gear drive shaft.

The invention according to claim 8 is dependent on the invention according to claim 7, wherein a center differential for allowing a rotation difference between the front wheels and the rear wheels is provided on the front wheel drive axle.

The invention as claimed in claim 9 is as follows.
According to the invention described in 3, 4, 5, 6, 7 or 8, the mating surface of the shaft supporting portion of the crankshaft is orthogonal to the cylinder axis of the engine.

[0015]

With the above construction, in the inventions according to any one of claims 1 to 5, when the case of the power train is assembled, the crank shaft and the shaft of the transmission or the shaft of the front wheel drive axle are passed through when the case is assembled. By assembling the cases at the mating surfaces and at the mating surfaces passing through the shaft support portion of the gear drive shaft provided separately from the mating surfaces, the cases of the powertrain can be assembled. The troublesome work of aligning and assembling the three cases with each other as in the case where the two mating surfaces cross each other is not necessary.

Further, in any of the sixth to eighth aspects of the invention, the crankshaft shaft support, the shaft of the transmission or the shaft support of the front wheel drive axle, and the shaft support of the gear drive shaft of the power transmission gear device are provided. Since they are all provided on the same mating surface, the cases can be easily assembled only by joining the cases to each other on this mating surface.

[0017]

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

1 to 3 show a power train of a four-wheel drive vehicle having a case structure according to a first embodiment of the present invention. In these drawings, 1 is a vehicle body, 2 is an engine room provided in the front part of the vehicle body 1, and the engine room 2 is separated from a vehicle compartment 4 by a dash panel 3. Inside the engine room 2, a radiator 5 is arranged on the front side thereof, and an engine 6 and a transmission 7 are arranged behind the radiator 5. The engine 6 is a four-cylinder reciprocating engine, and a crankshaft 8 is horizontally arranged in the vehicle width direction. The transmission 7 is horizontally arranged behind the engine 6 and in parallel with the crankshaft 11. It is located in.

Reference numeral 11 denotes a clutch provided at one end of the crankshaft 8 of the engine 6, and reference numeral 12 denotes the driving force (rotational force of the crankshaft 8) of the engine 6 output through the clutch 11. Input shaft 21
It is a power transmission means for transmitting to. The clutch 11 is
A support disc 13 is connected to the crankshaft 8 so as to rotate integrally with it, a clutch disc 14 is arranged to face the support disc 13, and a pressure plate 15 for pressing the clutch disc 14 against the support disc 13. ing. The power transmission means 12 is the clutch disc 1 of the clutch 11.
Drive sprocket 16 connected to 4 in a rotationally integrated manner
And a driven sprocket 17 rotatably and integrally provided on the input shaft 21 of the transmission 7, and the both sprockets 16 and 1
It is composed of a chain 18 wound between seven. Thus, when the clutch 11 is engaged (that is, when the clutch disc 14 is pressed by the support disc 13), the driving force of the engine 6 is applied to the power transmission means 1.
It is transmitted to the input shaft 21 of the transmission 7 via 2 and the input shaft 21 rotates.

The transmission 7 has an input shaft 21 and an output shaft 22 located on the coaxial line, and a counter shaft 23 parallel to these. The input shaft 21 and the counter shaft 23 are drivingly connected via a pair of reduction gears 24, while a gear train 25 for shifting is arranged between the output shaft 22 and the counter shaft 23. . Therefore, the engine driving force input to the input shaft 21 is transmitted from the input shaft 21 via the reduction gear 24 to the counter shaft 23.
Is transmitted to the output shaft 22 from the counter shaft 23 via any one gear of the speed-changing gear train 25, and is appropriately decelerated during this period.

A center differential 31 for dividing the driving force output from the transmission 7 into the front wheel side and the rear wheel side is arranged on the extension line of the output shaft 22 of the transmission 7, and the center differential 31 is arranged. Reference numeral 31 denotes a planetary gear type, which is provided with a ring gear 32 as an input portion that is connected to the output shaft 22 so as to rotate integrally therewith, and is provided concentrically with the ring gear 32 so as to rotate integrally with the rear wheel output gear 33. The connected sun gear 34 and the ring gear 32
And the planetary gear 35 that meshes with both the sun gear 34
And a carrier 37 that supports the planetary gear 35 and that is rotatably connected to the front-wheel output gear 36. A differential limiting device 38 including a viscous coupling that limits the differential rotation of the center differential 31 by limiting the relative rotation between the sun gear 34 and the carrier 37 is disposed on the side of the center differential 31.

Then, the center differential 3
The driving force on the front wheel side divided by 1 is the front wheel side output gear 36.
Is transmitted to a front bevel gear type front differential 41, divided into left and right by the front differential 41, and then transmitted to the left and right front wheels 9 via drive axles 42L and 42R, respectively. On the other hand, the driving force on the rear wheel side is transmitted from the rear wheel side output gear 33 to the rear differential (not shown) at the rear part of the vehicle body through the idle gear 43, the power transmission gear device 44 and the propeller shaft 45. The power transmission gear device 44 includes a gear drive shaft 46 extending in the vehicle width direction, a gear 47 provided at one end of the gear drive shaft 46 and meshing with the idle gear 43, and the other end of the gear drive shaft 46. And a pair of hypoid gears 48, 48 respectively provided at the front end of a shaft 49 connected to the propeller shaft 45.

Here, in order to describe in detail the positional relationship between the engine 6, the transmission 7, and other parts and members of the power train, as shown in FIG. 2, the engine 6 is located on the upper side (cylinder head side). ) Is tilted backward by about 45 degrees and is placed horizontally. The input / output shafts 21 and 22 of the transmission 7 and the shaft center P2 of the center differential 31 are set at a position rearward of the shaft center P1 of the crankshaft 8 of the engine 6, and the countershaft 23 of the transmission 7 is The axis P3 is set at a position in front of and below the axis P2 of the input / output shafts 21, 22.
Further, the shaft center P4 of the drive axles 42L, 42R of the front differential 41 and the front wheels 9 is set to
22 and the center differential is set to a position substantially directly below the axis P2 of the center differential. Further, the axis P5 of the idle gear 43 and the power transmission gear device 44 are arranged on a straight line extending rearward from the axis P2 of the center differential 31 and the like.
The shaft center P6 of the (gear drive shaft 46) is provided, and the shaft 49 or the propeller shaft 45 extends rearward in a substantially straight line from a position slightly below the shaft center P6 of the power transmission gear device 44. .

As shown in FIGS. 2 and 3, the transmission 7
And front differential 4 integrated with this
A cross member 51 having a closed cross-section structure is arranged near the rear of the vehicle 1 in the vehicle width direction, and a steering rack 52 extending in the longitudinal direction, that is, the vehicle width direction is arranged in the closed cross section of the cross member 51. The housing 52a of the steering rack 52 is fixed to the upper surface of the cross member 51. The cross member 51 has rising portions 51a rising and extending at both left and right ends thereof, and is connected and supported by a frame 53 extending in the vehicle front-rear direction at the rising portions 51a. The steering rack 52 is provided so as to be movable in the axial direction (vehicle width direction) by receiving a steering force through the pinion 54, and the left and right ends of the steering rack 52 are
Each of the cross members 51 extends from each rising portion 51a to the outside of the cross member 51, and is steerably connected to the front wheels 9 via a tie rod 55. The cross member 51
The steering rack 52 and the steering rack 52 are set at a position lower than the axial center P4 of the drive axles 42L and 42R of the front differential 41 and the front wheels 9, and the cross member 51.
Above the shaft, the hypoid gear 48, which is the power take-out portion of the propeller shaft 45, or the shaft center P of the power transmission gear device 44.
Six are provided.

Reference numeral 61 is an intake pipe connected to the intake port of each cylinder of the engine 6 and 62 is an exhaust pipe connected to the exhaust port of each cylinder of the engine 6 Reference numeral 62 designates four first exhaust pipes 63, 63, ... Independently communicating with the exhaust ports of the respective cylinders of the engine 6, and the first exhaust pipes 63, 63 ,. The second exhaust pipe 65 is connected. The four first exhaust pipes 63, 63, ... Are set to have substantially equal lengths, and are inclined downward from the rear of the upper portion on the cylinder head side of the engine 6 toward the rear of the transmission 7. Through which it is connected to the second exhaust pipe 65, and the second exhaust pipe 65 is
The central portion of the vehicle body in the vehicle width direction is arranged to extend rearward of the vehicle body.

FIG. 4 shows a case structure of a power train including the engine 6 and the transmission 7. In the case structure, the case 70 of the engine 6 is composed of a head cover 71, a cylinder head 72, an upper crankcase 73, a lower crankcase 74 and an oil pan 75 from the upper side, and the upper crankcase 73 and the lower part. The mating surface F1 with the crankcase 74 is a plane that passes through the axis P1 of the crankshaft 8 and is provided substantially orthogonal to the cylinder axis L1. The transmission 7 and the center differential 31 are mainly housed in the upper crankcase 73 of the engine 6, and these three parts
Cases 7 and 31 are integrated.

Further, the front differential 4 mentioned above
1 is stored so as to straddle the inside of the upper crankcase 73 and the lower crankcase 74 of the engine 6, and this differential case is integrally formed with the case of the engine 6. Case 74
The mating surface F1 with the front differential 41
And through the axis P4 of the drive axles 42L and 42R.
The power transmission gear device 44 is accommodated in the upper crankcase 73 and the gear case 76 in a straddled manner. The mating surface F2 between the upper crankcase 73 and the gear case 76 has a gear drive of the power transmission gear 44. It is a substantially vertical plane that passes through the axis P5 of the shaft 46 and is located above the rear end of the mating face F1 between the upper crankcase 73 and the lower crankcase 74. By the above, the engine 6, the transmission 7, which constitute the power train,
The case of the center differential 31, the front differential 41, and the power transmission gear device 44 are all integrally formed.

Therefore, in the case of the powertrain case of the first embodiment, the engine 6, the transmission 7, and the center differential 3 which constitute the powertrain.
1. Since the cases of 1, the front differential 41 and the power transmission gear device 44 are integrally structured, the devices can be brought close to each other, so that the power train can be made compact.

When assembling the powertrain case, the upper crankcase 73 and the lower crankcase 7 are assembled.
The crankshaft 8 and the front wheel drive axles 42L and 42R are fitted on the mating face F1 with the gear No. 4 and the gear drive shaft 46 is sandwiched on the mating face F2 between the upper crankcase 73 and the gear case 76 so as to pivotally support each other. By coupling, the above three types of shafts 8, 42
L, 42R, 46 can be assembled at the same time,
The assembling work can be simplified.

Moreover, since all the mating surfaces of the cases 71 to 76 of the power train including both mating surfaces F1 and F2 are provided so as not to cross each other, the cases can be relatively easily coupled. Therefore, the assembling work can be further simplified.

Further, in the case of the present embodiment, the engine 6 is arranged horizontally with the upper part of the engine 6 tilted backward,
The mating surface of the shaft support of the gear drive shaft 46 (the mating surface of the upper crankcase 73 and the gearcase 76) F2
Is provided above the rear end of the mating surface (the mating surface between the upper crankcase 73 and the lower crankcase 74) F1 of the crankshaft 8 and the shaft support portions of the drive axles 42L and 42R, so that the mating surface F2 is substantially vertical. As the surface, the cases can be easily connected to each other. Further, together with the gear drive shaft 46, the propeller shaft 45
Since the tip of the propeller shaft can be provided at a high position, the propeller shaft 45 can be linearly extended to the rear differential of the rear wheel side without bending up and down while securing the ground clearance of the propeller shaft 45. It is possible to reduce power transmission loss in the propeller shaft 45 and prevent vehicle vibration.

5 to 9 show a powertrain structure of a four-wheel drive vehicle and a case structure of the powertrain according to the second embodiment of the present invention. In the case of the second embodiment, the basic configuration of the power train such as the engine 6 and the transmission 7 is as follows.
Although it is the same as that of the first embodiment, the first configuration is that the driving force output from the transmission 7 is transmitted to the front wheels and the rear wheels.
This is different from that of the embodiment.

That is, as shown in detail in FIG. 8, an output gear 26 for outputting a driving force from the transmission 7 is attached to the end portion of the output shaft 22 of the transmission 7 by a spline coupling 27, and the output gear 26 is provided. 26 is rotatably supported on both sides thereof by bearings 28a and 28b as bearing portions. The driving force output from the output gear 26 is transmitted to the center differential 31 and is split into the front wheel side and the rear wheel side by the center differential 31. Then, the driving force on the front wheel side is transmitted to the front differential 41, which is a front wheel-to-wheel differential, is divided into left and right by the front differential 41, and is then transmitted to the left and right front wheels 9 via the drive axles 42L and 42R, respectively. Transmitted. On the other hand, the driving force on the rear wheel side is transmitted via the power transmission gear device 44 and the propeller shaft 45 to a rear differential (not shown) which is a rear wheel differential on the rear wheel side of the vehicle body.

The center differential 31 and the front differential 41 are arranged in parallel on the drive axles 42L and 42R, which are separate from the output shaft 22 of the transmission 7, and are connected to the front differential 4.
1 is a position on the drive axles 42L, 42R close to the vehicle body front-rear center line near the transmission 7 (this position corresponds to a position in the vehicle width direction corresponding to the transmission 28 side bearing 28b of the output gear 26). The center differential 31 is arranged at a position opposite to the transmission 7 with the front differential 41 interposed therebetween. Further, the center differential 31 is of a planetary gear type, and has a ring gear 32 as an input portion having a gear portion meshing with the output gear 26 on the outer periphery, a ring gear 32 provided concentrically with the ring gear 32, and a rear wheel. The sun gear 34, which is rotationally integrally connected to the side output gear 33, the planetary gear 35, which meshes with both the ring gear 32 and the sun gear 34, supports the planetary gear 35, and is rotationally integrally connected to the differential case 41a of the front differential 41. And the carrier 37 formed. On the other hand, the front differential 41 is of a bevel gear type, and one end of the differential case 41a of the front differential 41 (an end opposite to the transmission 7) has a sun gear 34 of the center differential 31.
An output gear 33, which is formed integrally with the sun gear 34 and meshes with a gear 47 of the power transmission gear device 44, is rotatably mounted, and a differential limiting device 38 including a hydraulic clutch is provided. The differential limiting device 38 limits the relative rotation between the output gear 33 and the differential case 41a, and thus the relative rotation between the sun gear 34 of the center differential 31 and the carrier 36, and limits the differential of the center differential 31. ing. The power transmission gear device 44 includes a gear drive shaft 46 extending in the vehicle width direction and the gear drive shaft 4
6, a pair of hypoid gears 48 provided at one end of a shaft 47 connected to the other end of the gear drive shaft 46 and the propeller shaft 45, respectively. And 48.

Also, the positional relationship among the engine 6, the transmission 7, and other parts and members of the power train are slightly different from those in the case of the first embodiment. That is, as shown in FIG. 6, the engine 6 has its upper side (cylinder head side).
Is placed horizontally with the front tilted slightly. The input / output shafts 21 of the transmission 7 are located at a position slightly rearward of and slightly above the axis P1 of the crankshaft 8 of the engine 6.
The shaft center P2 of 22 is set, and the shaft center P3 of the counter shaft 23 of the transmission 7 is set rearward and below the shaft center P2 of the input / output shafts 21, 22. Further, the center P31 of the center differential 31, the front differential 41, and the drive axles 42L, 42R of the front wheels 9 are set to a position substantially below the center P2 of the input / output shafts 21, 22. Further, the power transmission gear device 44 (the gear drive shaft 4 is provided at a position rearward and below the axis P4 of the center differential 31 and the like.
The shaft center P6 of 6) is provided, and the shaft 49 and the propeller shaft 45 extend rearward from a position slightly below the shaft center P6 of the power transmission gear device 44, that is, a position close to the bottom surface of the power train.

In the case of the second embodiment, the cross member 51 having the closed cross-section structure containing the steering rack 52 is provided between the exhaust pipe 62 above the power transmission gear device 44 which is the power take-out portion of the propeller shaft 45. Is arranged so as to extend in the front-rear direction of the vehicle body. The other configurations of the steering rack 52, the cross member 51, the exhaust pipe 62 and the like are the same as those in the first embodiment, and the same members are designated by the same reference numerals and the description thereof is omitted.

On the other hand, the case structure of the power train is basically the same as that of the case of the first embodiment, as shown in FIG. 9, and includes the engine 6, the transmission 7, the center differential 31, the front differential 41 and the power. All cases of the transmission gear device 44 are configured as an integral structure.

That is, the case 70 of the engine 6
Is composed of a head cover 71, a cylinder bed 72, an upper crankcase 73 and a lower crankcase 74 from the upper side, and the oil pan in the case of the first embodiment is integrally formed with the lower crankcase 74.
The upper crankcase 73 and the lower crankcase 74
The mating face F1 with the crankshaft 8 is a plane that passes through the axis P1 of the crankshaft 8 and the axes P1 of the input / output shafts 21 and 22 of the transmission 7, and is substantially orthogonal to the cylinder axis L1. 7 is accommodated in the upper crankcase 73 and the lower crankcase 74.

Further, the center differential 31
The front differential 41 and the front differential 41 are housed in the lower crankcase 74, and the drive axles 42L and 42R of the front wheels, which are coaxial with the differentials 31 and 41, are provided so as to penetrate the lower crankcase 74. . The power transmission gear device 44 is accommodated so as to extend across the inside of the lower crankcase 74 and the gear case 76, and the mating face F2 between the lower crankcase 74 and the gear case 76 is the gear drive of the power transmission gear 44. It is a plane that extends substantially vertically through the axis P5 of the shaft 46 and is located below the rear end of the mating face F1 between the upper crankcase 73 and the lower crankcase 74.

In the powertrain case structure of the second embodiment as well, the engine 6, the transmission 7, the center differential 31, the front differential 41 and the power transmission gear device 44 are all integrally structured, while the engine 6, the mating surface F1 between the upper crankcase 73 and the lower crankcase 74, which serve as the shaft support of the crankshaft 8 and the shaft support of the input / output shafts 21, 22 of the transmission 7, and the gear drive shaft of the power transmission gear device 44. Since the mating surface F2 of the lower crankcase 74 and the gear case 76, which serves as the shaft support of 46, is provided without crossing, the power train can be made compact as in the case of the first embodiment. The case assembling work can be simplified.

In addition, in the case of the second embodiment, the engine 6 is arranged horizontally with the upper part of the engine 6 tilted forward, and the mating surfaces (the lower crankcase 74 and the gear case 76) of the shaft support of the gear drive shaft 46 are arranged. (Mating surface with)
F2 is crankshaft 8 and input / output shaft 2 of transmission 7.
The mating surfaces of the shaft support portions of the 1 and 22 (the upper crankcase 73
By disposing the mating surface F2 below the rear end of the mating surface F1 between the lower crankcase 74 and the lower crankcase 74, the mating surfaces F2 can be made substantially vertical to facilitate coupling between the cases, and the power transmission gear device 44 can be used. Can be provided at a low position and the lubrication can be performed easily and satisfactorily.

FIG. 10 shows a case structure of a power train according to the third embodiment of the present invention. In the case of the third embodiment, the mechanical structure of the power train is not shown, but it is the same as that of the second embodiment, and the layout of the constituent members and parts of the power train is the engine 6
Is almost the same as the case of the second embodiment except that it is horizontally arranged with its upper part tilted rearward. In the following description, the member reference numerals in the drawings showing the second embodiment will be referred to. And in the case structure of the powertrain,
Engine 6, transmission 7, center differential 3
1, the front differential 41 and the case of the power transmission gear device 44 are all integrally configured. That is, the case 70 of the engine 6 is composed of a head cover 71, a cylinder bed 72, an upper crankcase 73, a lower crankcase 74, and an oil pan 75 from the upper side. The mating face F1 between the upper crankcase 73 and the lower crankcase 74 is located at the center P1 of the crankshaft 8 and the center differential 3.
1, front differential 41 and drive axle 42
It is provided substantially orthogonal to the cylinder axis L1 on a plane inclined rearward and downward, passing through the axis P4 of L and 42R and the axis P6 of the gear drive shaft 46 of the power transmission gear device 44. The transmission 7 is mainly housed in the upper crankcase 73, and the center differential 31, the front differential 41 and the power transmission gear device 44 are arranged in the upper crankcase 73 and the lower crankcase 74. It is stored across and. The axis L2 of the shaft 49 of the power transmission gear device 44 or the propeller shaft 45 is offset above the axis P6 of the gear drive shaft 46.

In such a case structure, in particular,
A mating surface F1 between the upper crankcase 73 and the lower crankcase 74 is provided through the axis P1 of the crankshaft 8, the axis P4 of the drive axles 42L and 42R, and the axis P6 of the gear drive shaft 46. The above three types of shafts 8, 42L, 42R, on one mating face F1
Since 46 is pivotally supported together, it is possible to reduce the number of divisions into which the case is divided in order to facilitate the assembling of the shaft, so that the cost can be reduced and the assemblability can be improved.

When the axis L2 of the propeller shaft 45 is offset above the axis P6 of the gear drive shaft 46 as in the third embodiment, the propeller shaft 45 is vertically moved while ensuring the ground clearance of the propeller shaft 45. Since it can be linearly extended to the rear differential on the rear wheel side without being bent, the power transmission loss at the propeller shaft 45 can be reduced and vibration of the vehicle body can be prevented.

In each of the above-mentioned first to third embodiments, the present invention is applied to the power train of the four-wheel drive vehicle provided with the center differential 31 which allows the rotation difference between the front wheels and the rear wheels. Although the case has been described, it is needless to say that the same can be applied to a power train of a four-wheel drive vehicle that does not have the center differential 31.

[0046]

As described above, according to the first to fifth aspects of the present invention, in the four-wheel drive vehicle of the type in which the engine and the transmission are installed horizontally and in parallel, the engine, the transmission, the front differential and the power transmission gear are provided. While the case of the device is integrally structured, the shaft support of the crankshaft and the support shaft of the transmission shaft or the front wheel drive axle are provided on the same mating surface with respect to the case, and the gear of the power transmission gear device is provided. By providing the shaft support of the drive shaft on the mating surface of the case other than the mating surface, the power train can be made compact and the case assembling work can be simplified.

In particular, according to the second aspect of the invention, the engine is arranged horizontally with the upper part of the engine tilted backward,
By providing the mating surface of the shaft support part of the gear drive shaft above the rear end of the mating surface of the crankshaft shaft support part, it is possible to secure the ground clearance of the propeller shaft without bending the propeller shaft up and down. Since it can be linearly extended to the rear differential on the rear wheel side, it is possible to contribute to reduction of power transmission loss and prevention of vehicle body vibration.

Further, in the invention according to claim 4, the engine is arranged horizontally with the upper part of the engine tilted forward,
By providing the mating surface of the shaft supporting portion of the gear drive shaft below the rear end of the mating surface of the shaft supporting portion of the crankshaft, the power transmission gear device can be lubricated easily and satisfactorily.

In any of the inventions described in claims 6 to 8,
In a four-wheel drive vehicle of a type in which an engine and a transmission are mounted horizontally and in parallel, the case of the engine, the transmission, the front differential, and the power transmission gear device is integrally structured, and the shaft support portion of the crankshaft with respect to the case. And the shaft portion of the transmission or the front-wheel drive axle and the shaft support portion of the gear drive shaft of the power transmission gear device are provided on the same mating surface, thereby reducing the number of divisions of the case while reducing the number of cases. It is possible to reduce the size and simplify the case assembling work.

In particular, according to the invention of claim 7, the axis of the propeller shaft is offset upward from the center of the gear drive shaft so that the propeller shaft can be straightened while ensuring the ground clearance. It is also possible to contribute to reduction of power transmission loss and prevention of vehicle body vibration.

[Brief description of drawings]

FIG. 1 is a skeleton diagram showing an overall configuration of a power train of a vehicle according to a first embodiment of the present invention.

FIG. 2 is a side view showing an arrangement state of a power train in a front portion of a vehicle body.

FIG. 3 is a plan view showing a disposition state of the power train, which is partially cut out.

FIG. 4 is a sectional view showing a case structure of a power train.

FIG. 5 is a view, corresponding to FIG. 1, showing a second embodiment of the present invention.

FIG. 6 is a view equivalent to FIG.

FIG. 7 is a view equivalent to FIG.

FIG. 8 is a cross-sectional view showing a configuration of a main part of a power train.

9 is a view corresponding to FIG. 4. FIG.

FIG. 10 is a view corresponding to FIG. 4, showing a third embodiment of the present invention.

[Explanation of symbols]

2 engine room 6 engine 7 transmission 8 crankshaft 31 Center differential 41 front differential 42L, 42R front wheel drive axle 44 power transmission gear device 45 propeller shaft 46 gear drive shaft 70 cases F1, F2 mating surface

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Ichiro Hirose             3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda             Within the corporation (72) Inventor Akutagawa et al.             3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda             Within the corporation

Claims (9)

[Claims] 1. An engine is arranged horizontally in the engine room at the front of the vehicle body with its crankshaft oriented in the vehicle width direction, and a transmission is arranged in parallel with the engine behind the engine. The drive axle of the front wheels and the axle of the front differential located coaxially with the axle are located rearward of the crankshaft of the engine, and the drive force is transmitted from the transmission to the rear of the axle. In a four-wheel drive vehicle in which a gear drive shaft of a power transmission gear device for transmitting to the vehicle is provided so as to extend in the vehicle width direction, the engine, the transmission, the front differential, and the case of the power transmission gear device are integrally structured. , The crankshaft shaft support portion and the transmission shaft or front wheel drive axle shaft support portion for the case are the same. A case structure of a power train, which is provided on a mating surface, and a shaft support portion of a gear drive shaft of the power transmission gear device is provided on a mating surface of a case different from the mating surface. . 2. The engine is horizontally arranged with its upper portion inclined rearward, and the engine of the gear drive shaft is arranged above a rear end position of a mating surface of a shaft support portion of the crankshaft. The case structure for a power train according to claim 1, wherein a mating surface of the shaft support portion is provided. 3. The powertrain case structure according to claim 2, wherein a center differential that allows a rotation difference between the front wheels and the rear wheels is provided coaxially with the shaft of the transmission. 4. The engine is horizontally arranged with its upper part inclined forward, and the engine of the gear drive shaft is arranged below a rear end position of a mating surface of a shaft support portion of the crankshaft. The case structure for a power train according to claim 1, wherein a mating surface of the shaft support portion is provided. 5. The powertrain case structure according to claim 4, wherein a center differential that allows a rotation difference between the front wheels and the rear wheels is provided on the front-wheel drive axle. 6. The engine is arranged horizontally in the engine room at the front of the vehicle body with its crankshaft oriented in the vehicle width direction, and a transmission is arranged in parallel with the engine behind the engine. The front axle of the front wheel and the axle of the front differential located on the same axis as the front axle are located rearward of the crankshaft of the engine, and the drive force is transmitted from the transmission side to the rear of the axle. In a four-wheel drive vehicle in which a gear drive shaft of a power transmission gear device for transmitting to a shaft is provided extending in the vehicle width direction, the engine, the transmission, the front differential, and the case of the power transmission gear device are configured integrally. And the shaft supporting part of the crankshaft and the shaft supporting part of the transmission or the front wheel drive axle for the case are the same. Provided on the mating surfaces, powertrain case structure, characterized in that provided in the shaft support same mating surface on the gear drive shaft of the power transmission gear apparatus. 7. The engine is horizontally arranged with its upper part inclined rearward, and the axis of the propeller shaft is located above the center of the gear drive shaft of the power transmission gear device. The case structure of the power train according to claim 6, wherein the case structure is offset. 8. The powertrain case structure according to claim 7, wherein a center differential that allows a rotation difference between the front wheels and the rear wheels is provided on the front wheel drive axle. 9. The powertrain of claim 1, 2, 3, 4, 5, 6, 7 or 8, wherein a mating surface of the shaft supporting portion of the crankshaft is substantially orthogonal to a cylinder axis of the engine. Case structure.