JPS5975836A - Four-wheel-drive vehicle - Google Patents

Abstract

PURPOSE:To reduce size of a transmission unit in the lateral direction of a vehicular body, by arranging an interaxle differential gear for a laterally arranged engine on a longitudinal axis of the vehicular body, and to improve comfortability in a compartment, by accommodating the unit in a tunnel provided at the center of a floor surface of the vehicular body. CONSTITUTION:An axis of an interaxle differential gear 15 for dividing a power output to a front and a rear axle extends along the longitudinal direction of a vehicular body, and is arranged on an axis different from that of an interfrontwheel differential gear 23 having an axis in the lateral direction of the vehicular body. Both the differential gears 15 and 23 are juxtaposed in the logitudinal direction of the vehicular body. Accordingly, it is possible to form a longitudinally extending transmission unit 12 integrally mounted to a power plant 1 and constituted of the interaxle differential gear 15 and the interfrontwheel differential gear 23, and accommodate the unit 12 in a tunnel provided at the center of a floor surface of the vehicular body. Particularly, as the differential gear 15 is a planetary gear mechanism, the longitudinal size of the transmission unit 12 may be made relatively short in spite of its longitudinally extended shape. As a result, it is possible to secure a space for a compartment, and improve comfortability and driveability of an automobile.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a four-wheel drive vehicle, and more particularly to a four-wheel drive vehicle with a transversely mounted engine.

In four-wheel drive vehicles, an inter-axle differential is installed at the drive force splitting section from the power plant to the front and rear axles in order to absorb the difference in rotational speed between the front and rear axles that occurs when turning. It will be done. Further, the front axle and the rear axle are respectively provided with a front wheel differential device and a rear wheel differential device that absorb the rotational speed difference between the left and right wheels that occurs during turning.

However, in conventional four-wheel drive vehicles, for example,
-154328 and JP-A-57-41216, the inter-axle differential (planetary gear in @'s publication, intermediate differential in the latter's publication) and the power plant. The closer inter-wheel differential device If (the final reduction gear on the front wheel side in the former publication, and the front differential device in the latter publication) is arranged on the same axis in the vehicle width direction. As a result, the dimensions of the transmission unit in the vehicle width direction, which consists of the inter-axle differential installed integrally with the power plant and the inter-wheel differential on the power plant side, become large, especially in the engine compartment of small cars. If there is not enough space in the longitudinal direction, the engine compartment must protrude wide toward the passenger compartment in order to accommodate the transmission unit, and in automobiles with a power plant located at the front of the vehicle body, The space under the driver's seat becomes narrower, making maneuverability worse.

The present invention solves the above-mentioned problems in conventional four-wheel drive vehicles with a horizontal engine. By locating it on the longitudinal axis, the dimensions in the vehicle body width direction of the transmission unit consisting of the inter-axle differential device provided integrally with the power plant and the inter-wheel differential device on the power plant side can be reduced. As a result, the unit can be housed in a tunnel provided in the center of the floor of the vehicle body, or the width of the engine room protruding into the vehicle interior can be set to an extremely narrow range in the center, so that the unit can be placed inside the vehicle interior for driving or other purposes. Ensure sufficient space for living.

That is, the present invention provides a power plant arranged such that the crankshaft of the engine and the input/output shaft of the transmission extend in the width direction of the vehicle; a first bevel gear provided at the output end of the transmission; a second bevel gear disposed in the longitudinal direction of the vehicle body and constantly meshed with the first bevel gear, and a planetary gear mechanism;
an inter-axle differential whose + wire is arranged in the longitudinal direction of the vehicle body and whose input portion is connected to the second bevel gear; and a third bevel gear connected to one output member of the inter-axle differential. a fourth bevel gear whose axis is disposed in the vehicle width direction and is always meshed with the third bevel gear; an input section is connected to the fourth bevel gear; and two output members are connected to the power plant side. An inter-wheel differential device connected to the axles of a pair of left and right wheels, respectively, and another inter-wheel differential device connected to the other output member of the inter-axle differential device and extending in the longitudinal direction of the vehicle body. and a drive shaft that drives a pair of left and right wheels on the side opposite to the power plant. As a result, the dimension in the vehicle body width direction of the transmission unit consisting of the inter-axle differential device provided integrally with the power platform and the inter-wheel differential device on the power plant side is reduced, and the above object is achieved.

Hereinafter, the present invention will be explained based on embodiments shown in the drawings.

As shown in FIG. 1, the power plant 1 is arranged at the front of the vehicle body. The engine 2 and transmission 3 that constitute this power plant 1 are connected to a crankshaft 4 in the engine 2, an input shaft 6 connected to the crankshaft 4 in the transmission 3 via a clutch 5, and a link between the input shaft 6 and and an output shaft 8 on which a speed change gear mechanism 7 is interposed, are both arranged laterally so as to extend in the width direction of the vehicle body. The output section of the transmission 3 is equipped with a second output shaft 11 parallel to the output shaft 8 and connected to the shaft 8 through a gear 9 and 10, and at its output end,
A first bevel gear 14 that introduces power from the power plant 1 to the transmission unit 12 that is integrally provided in the plant 1!
' is provided.

As shown in an enlarged view in FIG. 2, the input portion of the transmission unit 12 is equipped with a second bevel gear 14 having an axis in the longitudinal direction of the vehicle body, and is constantly meshed with the first bevel gear 13. A small-to-small differential gear 15 is disposed on the same line 111 as the second bevel gear 14.

This inter-axle differential device 5 carries a ring gear 16, a sun gear 17, a plurality of planetary pinions 18...18 that mesh with the pushing gear 16 and the sun gear 17, and the pinion offs 18...18. pinion carrier 19
The second bevel gear 1 is composed of a planetary gear mechanism consisting of
4 is connected to the glue/gear 16 as an input member of the inter-axle differential device 15. A third bevel gear 21 repositioned coaxially with the second bevel gear 14 is connected to the sun gear 17, which is one output part of the inter-axle differential device 15, via a hollow shaft 20. A fourth bevel gear 22 having an axis in the vehicle width direction is always meshed with the third bevel gear 21.

The fourth bevel gear 22 is connected to an input member 24 of a front wheel differential 23 whose axis coincides with that of the fourth bevel gear 22 . Here, in the illustrated embodiment, the front wheel differential device 23
The input member is a differential case 24, a pin 25 installed in the case 24 in a direction perpendicular to its axis, and a pair of pinions 26 made of bevel gears rotatably supported by the pin 25. .27 and both vinyl spears 26, 2
A pair of side gears 28, also made of bevel gears, mesh with gear 7.
．． A bevel gear type differential device consisting of 29 is used. The two output parts of the front wheel differential 23, that is, the pair of side gears 28 and 29 are connected to the power platform 1 side shown in FIG. The left and right front wheels 32 and 33 are connected.

On the other hand, the pinion carrier 19, which is the other output part of the inter-axle differential device 15, has a pinion carrier 19 that extends in the longitudinal direction of the vehicle body and passes through a hollow shaft 20 that connects the sun gear 17 and the third bevel gear 2. A wheel drive shaft 34 is connected. As shown in FIG. 1, the drive shaft 34 is connected to a propulsion shaft 35 that also extends in the longitudinal direction of the vehicle body, and furthermore, left and right rear axles 37 that extend in the width direction of the vehicle body via a rear wheel differential 36. .38 or left and right rear wheels 3 on the side opposite to the power plant 1
Painted at 9.40.

Since the power transmission unit 12 is configured by a planetary gear mechanism that can reduce the modulus, even if the transmission unit 12 is vertically long, its longitudinal dimension can be made relatively short.

Although the planetary gear mechanism shortens the axial dimension, it tends to increase the radial dimension (vehicle width direction). 5 is located in the power plan (M) of the transmission unit 12 between the interwheel differential 23 and the power plant 1, making it easier to push the unit 12 into a tunnel, for example.

In the above embodiment, as shown in FIG. 3, the ring gear 16 and the sun gear 1 in the interaxle differential 15
A plurality of pinions 18 . . . 18 between the pinion 1
8a and a pinion 18b meshing with the sun gear 17, the input from the ring gear 16 is divided approximately equally between the sun gear 17 and the pinion carrier 19.

Next, a second embodiment of the present invention shown in FIG. 4 will be described.

In this second embodiment, an auxiliary transmission mechanism 102 is provided at the output section of a transmission 101 constituting a power plant, and a four-wheel drive/two-wheel drive switching mechanism 123 and a differential lock mechanism 114 are provided in a transmission unit 112. The auxiliary transmission mechanism 102 includes two gears 164 and 105 for high and low speeds fixedly attached to the output shaft 103, and loosely fitted to a second output shaft 106 parallel to the output shaft 10.3. Gear 104
Two gears 107 and 108 for high and low speeds are always meshed with the gears 105, respectively, and the two gears 107 and 108 are slidably provided on the second output shaft 106, and the two gears 107 and 108 are selectively connected to the second output shaft. High/low speed switching member 10 coupled to output shaft 106
It consists of 9.

Assuming that, for example, a gear ratio of four forward speeds and one reverse speed can be obtained between the input and output shafts of the transmission 1o1, the output of the second output shaft 106, that is, the first bevel gear 110
The power input to the transmission unit 112 via the second bevel gear 111 is switched to eight forward speeds and two reverse speeds.

Still, the differential lock mechanism 114 of the vehicle I differential RJ'I3 in the upper Nt' (jy movement unit 112 is
The ring gear 115 in the inter-axle differential 1σ113 is extended to the hollow shaft 118 connecting the sun gear 116 and the third bevel gear 117, and splines 119, 120 of the same diameter are placed adjacent to the extended portion and the hollow shaft 118. At the same time, as shown in the figure, the two splines 119, 12 are slid in the entry direction from the state where they are fitted onto one spline 1]9.
Sleeve 121 that can be switched to a fitted state across 0
It is composed of: According to such a configuration, the sleeve 121 is connected to one spline 119.
In the state where it is fitted only to the axle differential device
The power input to the ring gear 115 of the sun gear 1]6
and the pinion carrier 122, i.e., the front axle and the rear axle,
It is divided and transmitted according to the load acting on each,
When the sleeve 121 is fitted across both splines 119 and 120, the ring gear 115 and sun gear 116 of the inter-axle differential 113 are coupled. The dynamic function is eliminated, and power is transmitted equally to the front and rear axles regardless of their respective loads.

Further, the four-wheel drive/two-wheel drive switching mechanism 123 includes a second drive shaft 125 on an extension of the rear wheel drive shaft 124 connected to the pinion carrier 122 in the inter-axle differential device 113.
Splines 126, 127 having the same diameter are provided adjacent to the opposite ends of both moving shafts 124, 125, and both splines 126, 127 are provided as shown in the figure.
2. From the fitted state across 7, one spline 12
6 (or 127), which is slid into the fitted state.

Therefore, the sleeve 128 has both splines 126.12
7, the drive shaft 124 and the second drive shaft 125 are connected, and the pinion carrier 122 of the inter-axle differential 113 is connected to the rear wheel side via both drive shafts 124, 125. Power is transmitted to the sleeve 128.
When the spline 126 (or 127) is slid to fit only one spline 126 (or 127), the drive shaft 124 and the second drive shaft 125 are disconnected, and the power to the rear wheels is cut off and only the MiJ wheels are connected. The vehicle is in two-wheel drive mode.

In addition, the above 1. In the second embodiment, a double pinion type planetary gear mechanism is used as the planetary gear mechanism constituting the inter-axle differential, but a single pinion type may be used. In this case, the carrier is the input member, and the sun gear and ring gear are both output parts. Front wheel differential device 23
．． A bevel gear type differential device is used as the 129, but instead of this, a planetary gear type consisting of a Sankia, a ring gear, a planetary pinion that meshes with both, and a pinion carrier that supports the pinion is used. A differential device may also be used. In this case, the sun gear, ring gear,
One of the pinion carriers serves as an input member into which power is input from the inter-axle differential, and the other two serve as output members that drive the pair of left and right axles, respectively.

Although the above description is about an embodiment in which the power plant is disposed at the front of the vehicle body, the same configuration can be implemented even when the power plant is disposed at the rear of the vehicle body.

In this case, the transmission units 12, 112 that are integrally provided in the power plant are constituted by an inter-axle differential device and a rear-wheel differential device.

As described above, according to the present invention, a transmission unit consisting of an inter-axle differential device provided integrally with a power plant in a four-wheel drive vehicle and one inter-wheel differential device on the power plant side is It is configured in a vertically elongated shape with a small directional dimension.

Therefore, when the transmission unit can be inserted into a tunnel provided in the center of the vehicle body floor surface, or when the engine/gin room is protruded into the vehicle interior to accommodate the unit, the width of the protrusion can be reduced. An extremely narrow area in the center of the vehicle compartment is sufficient.

This prevents the interior space from being significantly sacrificed, and improves the comfort of the vehicle and the maneuverability when the power plant is located at the front of the vehicle body.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a first embodiment of the present invention, FIG. 2 is an enlarged plan view of essential parts of the embodiment, and FIG. 3 is a diagram showing FIG.
FIG. 4 is a sectional view taken along the line II, and an enlarged plan view of essential parts showing a second embodiment 11 of the present invention. 1... Power plant, 2... Engine, 3,101
... Transmission, 13,110... First bevel gear, 14,111... Second bevel gear, 15.113.
・Differential device between cars 1h11, 16,115...Ring gear, 17,116...Sun gear, 19.122...
Pinion carrier, 21,117...Third bevel gear, 2
2... Fourth bevel gear, 23°] 29... Inter-wheel differential device (front wheel differential device), 24... Input member (differential case), 28° 29... Output member (side gear ), 3
0.31... Axle (front axle), 32.33... Wheel (front wheel), 34.124.125... Drive shaft, 36
... Wheel differential device (rear wheel differential device), 37.3
8... Axle (rear axle), 39.40... Wheel (rear wheel).

Claims (4)

[Claims] (1) A power plant arranged such that the engine's crankshaft and the transmission's input/output shaft extend in the width direction of the vehicle; a first bevel gear provided at the output end of the transmission; A planetary gear type consisting of a second bevel gear disposed vertically and always meshing with the first bevel gear, a sun gear, a ring gear, a planetary pinion meshing with both, and a pinion carrier supporting the pinion. A differential between wheels, the axis of which is arranged in the longitudinal direction of the vehicle body and whose input section is connected to the second bevel gear, and one output section of this differential between wheels. a fourth bevel gear whose axis is disposed in the width direction of the vehicle body and is constantly meshed with the third bevel gear; and an input member is connected to the fourth bevel gear.
an inter-wheel differential connected to the axles of the pair of left and right wheels on the power plant side, and an inter-wheel differential connected to the other output member of the inter-wheel differential and extending in the longitudinal direction of the vehicle body. 1. A four-wheel drive vehicle, comprising: a drive shaft that drives a pair of left and right wheels on the side opposite to the power plant via an inter-wheel differential device. (2) The four-wheel drive vehicle according to claim 1, wherein the power plant is disposed at the front of the vehicle body. (3) The four-wheel drive vehicle according to claim 1 or 2, wherein the inter-wheel differential device is disposed between the power plant and the inter-wheel differential device on the power plant side. (4) A patent claim in which the inter-wheel differential on the power plant side is a differential consisting of a group of bevel gears and a differential case, and the fourth bevel gear is fixed to the differential case of the inter-wheel differential. A four-wheel drive vehicle according to item 1, item 2, or item 3.