JPH04249663A - Power transmission device for four-wheel drive vehicle - Google Patents

Abstract

PURPOSE:To easily carry out the position deflection compensation of a case by holding each one edge side of a main shaft and countershaft and a transfer pinion shaft onto an internal combustion engine side case and holding the other edge side of the main shaft and the countershaft onto a central case. CONSTITUTION:A trans axle 2 is constituted of a speed change gear part 6, rear operation part 10, transfer part 12, and a 4WD selector part 12. A trans axle case 42 is constituted of a right case 44 as internal combustion engine side case, left case 46 as center case, side case 48, side cover 50, etc. Each one edge side of a main shaft 16 and a countershaft 18 and a transfer pinion shaft 28 is held by the right case 44, and the other edge sides of the main shaft 16 and the countershaft 18 are held on the left case 46. Further, an elastically deformable O-ring 126 is interposed at the connection part of an extension case part 52 and a transfer front case part 54.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] This invention relates to a power transmission device for a four-wheel drive vehicle, and in particular reduces the number of oil seal bodies in a transaxle, protects an extension shaft, and simultaneously processes two cases. is not necessary,
Moreover, the present invention relates to a power transmission device for a four-wheel drive vehicle in which case misalignment can be compensated for by an oil seal body.

0002

2. Description of the Related Art A four-wheel drive vehicle (4WD vehicle) is equipped with a power transmission device that transmits driving force input from an internal combustion engine from an output shaft of a transaxle to a propulsion shaft. The transaxle includes a clutch section that connects and disconnects the driving force of the internal combustion engine, a speed change gear section that has a main shaft equipped with a plurality of main gear trains, a counter shaft equipped with a plurality of counter gear trains, and a reduction gear section. a differential section connected to the speed change gear section via a transfer section; and a transfer section including a transfer pinion shaft and an extension shaft that are connected to the reduction gear section and are substantially orthogonal to the main shaft to distribute driving force. Consists of etc.

The clutch section, transmission gear section, differential section, and transfer section are enclosed by a transaxle case that is divided into a plurality of parts.

The structure of such a transaxle is disclosed, for example, in Japanese Utility Model Publication No. 3298/1983. The system described in this publication has a crown gear and a pinion gear meshed with each other by a hypoid gear, the transmission case is divided by a plane connecting the main shaft center of the transmission and the axle center of the differential, and the pinion gear unit is divided into two parts. By housing it in one case part,
This facilitates the work of assembling gears, especially the backlash adjustment work of the crown gear and pinion gear for power extraction.

[0005]

[Problems to be Solved by the Invention] However, in the conventional transaxle structure, an oil seal body must be provided between each of the plurality of divided transaxle cases, which increases the number of oil seal bodies. In addition, the assembly work was troublesome.

Furthermore, since the extension shaft is exposed to the outside, it is necessary to apply anti-rust treatment to the extension shaft or to provide a protective cover.

Furthermore, two parts are attached to one case by bolting.
When attaching two cases, it is necessary to simultaneously process the two cases, and when a case misalignment occurs, it becomes troublesome to compensate for this misalignment.

[0008]

[Means for Solving the Problems] Therefore, in order to eliminate the above-mentioned disadvantages, the present invention provides a transmission system having a main shaft provided with a plurality of main gear trains and a counter shaft provided with a plurality of counter gear trains. A differential section connected to the speed change gear section via a gear section and a reduction gear section, and a transfer pinion shaft and an extension shaft that are connected to the reduction gear section and are substantially perpendicular to the main shaft to distribute driving force. In a power transmission device for a four-wheel drive vehicle having a transaxle comprising a transfer section provided with a transfer section, an internal combustion engine side case is provided that holds one end side of the main shaft and the counter shaft and the transfer pinion shaft, A central case is provided that is attached to the internal combustion engine side case and has an extension case portion that holds the other end sides of the main shaft and the counter shaft and encloses the extension shaft, and one end side of the extension shaft is provided. a transfer front case that holds and attaches to the internal combustion engine side case; a transfer rear case that holds and attaches the long ends of the transfer pinion shaft and the extension shaft to the transfer front case; The invention is characterized in that an elastically deformable oil seal body is interposed at the connecting portion of the transfer front case portion.

[0009]

[Operation] According to the structure of the present invention, one end side of each of the main shaft and the counter shaft and the transfer pinion shaft are held in the internal combustion engine side case, and the other end sides of the main shaft and the counter shaft are held in the central case. let

[0010] Then, the transfer front case is attached to the internal combustion engine side case, a part of this transfer front case is connected to the extension case with an oil seal interposed therebetween, and the transfer rear case is attached to the transfer front case. .

Therefore, when misalignment occurs in the transfer front case, the misalignment is compensated for by the elastic deformation of the oil seal body. This eliminates the need for simultaneous machining of the central case and transfer front case.

[0012] Furthermore, the oil seal body serves as a seal between the central case and the transfer front case.

Furthermore, since the extension shaft is covered by the extension case portion of the central case, the extension shaft can be protected.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described in detail and specifically below with reference to the drawings.

1 to 9 show embodiments of the present invention. In FIG. 1, 2 is a transaxle connected to an internal combustion engine (not shown) installed horizontally at the rear of the vehicle body of a four-wheel drive vehicle (4WD vehicle).

This transaxle 2 has a clutch section 4
It consists of a transmission gear section 6, a reduction gear section 8, a rear differential section 10, a transfer section 12, and a 4WD switching section 14.

The clutch section 4 connects and connects the driving force from the internal combustion engine to the speed change gear section 6.

The speed change gear unit 6 includes a main shaft 16 provided with a plurality of main gear trains, and a counter shaft 1 provided with a plurality of counter gear trains arranged substantially parallel to the main shaft 16.
8.

The reduction gear section 8 is constructed by a reduction drive gear 20 fixed to the counter shaft 18 meshing with a reduction drive gear 24 fixed to the differential case 22 of the rear differential section 10.

Although not shown in this rear differential section 10,
Left and right drive axles are connected to left and right rear wheels.

The transfer section 12 is connected to the differential case 2.
A transfer bevel pinion gear 30 fixed to a transfer pinion shaft 28 disposed substantially perpendicular to the main shaft 16 is engaged with a transfer drive bevel gear 26 fixed to the main shaft 16, thereby connecting to the rear differential section 10. .

A drive sprocket 32 is fixed to the other end of the transfer pinion shaft 28.

Furthermore, an extension shaft 3 extends toward the front of the vehicle approximately parallel to the transfer pinion shaft 28.
4 are arranged.

A driven sprocket 36 is fixed to the other end of the extension shaft 34.

A drive chain 38 is wound around the drive sprocket 32 and the driven sprocket 36.

The other end of the extension shaft 34 has a 4W
It is connected to the transfer output shaft 40 via the D switching section 14 .

The 4WD switching section 14 connects the extension shaft 34 and the transfer output shaft 40 when driving a four-wheel drive vehicle, and connects the extension shaft 34 and the transfer output shaft 40 during normal two-wheel drive. 4
0.

The transfer output shaft 40 is connected to a front propulsion shaft (not shown).

Each part of the transaxle 2 is covered by a transaxle case 42.

The transaxle case 42 includes a light case 44 that is an internal combustion engine side case, a left case 46 that is a central case that is attached to the light case 44 in the axial direction, and a left case 46 that is attached to the left case 46 in the axial direction. A side case 48, a side cover 50 that covers the side case 48, and a cylindrical transfer front case that is attached to the light case 44 on the rear differential 10 side and connected to one end side of the extension case portion 52 of the left case 46. 54, a transfer rear case 56 that covers the transfer front case 54, and an output side case 58 attached to the other end side of the extension case section 52.

The light case 44 holds one end of each of the main shaft 16 and the counter shaft 18, one side of the differential case 22 of the rear differential 10, and the transfer pinion shaft 28, and also holds the clutch portion 4 and the rear differential. It accommodates the moving part 10.

Therefore, as shown in FIG. 3, the light case 44 has a first main bearing hole 68 for holding a first main bearing 66 that rotatably supports one end of the main shaft 16.
and a first rotatably supporting one end side of the counter shaft 18.
First counter bearing hole 72 that holds the counter bearing 70
and a first differential case bearing hole 7 that holds a first differential case bearing 74 that rotatably supports one side of the differential case 22.
6, and a clutch part housing space 78 that accommodates the clutch part 4.
and a differential housing space 80 that accommodates the rear differential unit 10.

A bearing hole 84 is formed in the light case 44 to hold a pinion tapered roller bearing 82 that rotatably supports the transfer pinion shaft 28. This pinion tapered roller bearing 82 is fixed to the light case 44 with a bearing mounting bolt 86.

The left case 46 is connected to the main shaft 1.
6 and the other end side of the counter shaft 18, and the other side of the differential case 22 of the rear differential section 10, and also accommodate the transmission gear section 6 and attach a mounting bolt (not shown) to the light case 44. (2).

Therefore, as shown in FIG. 5, the left case 46 has a second main bearing hole 90 that holds a second main bearing 88 that rotatably supports the other end of the main shaft 16.
and a second rotatably supporting the other end of the counter shaft 18.
A second counter bearing 94 that holds the counter bearing 92 and a second differential case bearing that holds the second differential case bearing 96 that rotatably supports the other end side of the differential case 22 of the rear differential section 10. A use hole 98 is formed, and a gear housing space 100 for housing each gear train of the main shaft 16 and the counter shaft 18 is formed.

A side case 48 is fixed to the left case 46 in the axial direction by side case bolts 102.

This side case 48 has an extremely low speed gear portion 1 extending to the other end side of the main shaft 16 and the counter shaft 18.
04 and is covered by a side cover 50.

Further, the left case 46 is integrally provided with the extension case portion 52 that encloses the extension shaft 34.

The extension case section 52 is arranged substantially perpendicular to the main shaft 16, with one end extending to the vicinity of the light case 44 on the transfer pinion shaft 28 side, and the other end extending near the light case 44 on the clutch section 4 side. It extends slightly protruding from the light case 44.

The transfer front case 54 includes:
As shown in FIGS. 8 and 9, it is formed into a cylindrical shape and is attached to the light case 44 with a front case bolt 106 and a second rear case bolt 108.

As shown in FIG. 9, the transfer front case 54 includes a first extension bearing 1 that rotatably supports a portion of one end of the extension shaft 34.
10, a chain housing space 104 for housing the drive chain 38, etc., a rear case bolt threaded hole 118 for screwing the first rear case bolt 116, and a second rear case bolt 116.
A front bolt insertion hole 120 into which the bolt 08 is inserted is formed.

[0042] Also, this transfer front case 5
4 is connected with a connecting protrusion 122 that protrudes toward the extension case portion 52 side.

[0043] This connecting protrusion 122 is fitted into a connecting case end portion 124 formed to widen the extension case portion 52.

An elastically deformable oil seal body is provided on the outer surface of the connecting protrusion 122 to provide a seal between the connecting case end 124 and the connecting protrusion 122 and to compensate for misalignment of the transfer front case 54. A seal groove 128 into which an O-ring 126 is fitted is formed.

A shaft insertion hole 130 through which the extension shaft 34 is inserted is formed in the connecting protrusion 122 .

The transfer rear case 56 holds the other end of the transfer pinion shaft 28 and one end of the extension shaft 34, and covers the drive chain 38 and the like.

Therefore, the transfer case 56 has a pinion bearing hole 134 that holds a pinion bearing 132 that rotatably supports the end of the transfer pinion shaft 28. and a second extension bearing hole 138 that holds a second extension bearing 136 that rotatably supports the most end portion of the extension shaft 34.

A second extension bearing hole 142 is formed at the other end of the extension case portion 52 to hold a third extension bearing 140 that rotatably supports the other end of the extension shaft 34 .

Next, the operation of this embodiment will be explained.

One end of the main shaft 16, one end of the counter shaft 18, one end of the differential case 22, and the transfer pinion shaft 28 are held by a light case 44.

Further, the other end of the main shaft 16, the other end of the counter shaft 18, and the other end of the differential case 22 are held by a left case 46.

At this time, the other end of the extension shaft 34, that is, the end on the output side, is held by the other end of the extension case portion 52.

Further, a portion of one end of the extension shaft 34 is held by the transfer front case 54,
Transfer front case 54 is fixed to light case 44 with front case bolts 106.

At this time, the extension case portion 52
A connecting protrusion 122 fitted with an O-ring 126 is inserted into the connecting case end 124 of the connecting case. Therefore, misalignment of the transfer front case 54 is compensated for by elastic deformation of the O-ring 126.

Then, the drive chain 38 and the like are accommodated, and the transfer rear case 56 is attached to the transfer front case 54 using first rear case bolts 108 and second rear case bolts 116.

As a result, the extension shaft 34 is covered by the extension case 52 and the transfer case 56, which are integrated with the left case 46, so that the extension shaft 34 is not exposed to the outside and is not subjected to rust-proofing treatment or a cover. The extension shaft 34 can be protected without providing any.

Furthermore, even though the left case 46 and the transfer front case 54 are not processed at the same time, even if the transfer front case 54 is misaligned, the O-ring 126, which is an oil seal body, absorbs this misalignment. , there is no problem, and this O-ring 126
also serves to seal this connection.

Further, according to the configuration of the present invention, it is possible to simplify the configuration by eliminating the need for an oil seal body for each case and reducing the number of oil seal bodies.

[0059]

As is clear from the above detailed description, according to the present invention, an internal combustion engine side case that holds one end side of the main shaft and the counter shaft and the transfer pinion shaft is provided, and the other side of the main shaft and the counter shaft are A transfer front case is provided with a central case that is attached to the internal combustion engine side case and has an extension case portion that holds the end side and encloses the extension shaft, and that is attached to the internal combustion engine side case while holding one end side of the extension shaft. A transfer rear case is provided which is attached to the transfer front case while holding the ends of the transfer pinion shaft and the extension shaft, and an elastically deformable oil seal body is provided at the connection portion between the extension case part and the transfer front case. This design reduces the number of oil seal bodies on the transaxle, making assembly work easier, and also effectively protects the extension shaft. Compensation is made by the body, the structure is simplified, and simultaneous machining of two cases is not required.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a transaxle of a four-wheel drive vehicle.

FIG. 2 is a right side view of the light case.

FIG. 3 is a cross-sectional view of the light case taken along the line ⓓ-ⓓ of FIG. 2;

FIG. 4 is a right side view of the left case.

FIG. 5 is a sectional view of the left case taken along the line ⓓ-ⓓ of FIG. 4;

FIG. 6 is a right side view of the left case.

7 is a plan view of the left case in FIG. 6. FIG.

FIG. 8 is a side view of the transfer front case.

9 is a sectional view of the transfer front case taken along the line ⓓ-ⓓ of FIG. 8;

[Explanation of symbols]

2 Transaxle 10 Rear differential part 12 Transfer section 28 Transpinion shaft 34 Extension shaft 42 Transaxle case 44 Light case 46 Left case 52 Extension case part 54 Transfer front case 56 Transfer case 122 Connecting protrusion 124 Connection case end 126 O-ring

Claims (1)

[Claims] Claims: 1. A differential gear connected to the speed change gear section through a speed change gear section and a reduction gear section having a main shaft provided with a plurality of main gear trains and a counter shaft provided with a plurality of counter gear trains. and a transfer part that is connected to the reduction gear part and is provided with a transfer pinion shaft and an extension shaft that are substantially perpendicular to the main shaft to distribute driving force. In the force transmission device, an internal combustion engine side case is provided that holds one end side of the main shaft and the counter shaft and the transfer pinion shaft, and holds the other end side of the main shaft and the counter shaft, and the extension shaft. a central case that is attached to the internal combustion engine side case and has an extension case portion enclosing the transfer shaft; a transfer front case that holds one end of the extension shaft and is attached to the internal combustion engine side case; A transfer rear case is provided that is attached to the transfer front case while holding the long end portions of the pinion shaft and the extension shaft, and an elastically deformable oil seal body is provided at the connection portion between the extension case portion and the transfer front case portion. A power transmission device for a four-wheel drive vehicle characterized by the following: