JPH0551488B2 - - Google Patents

Description

[Detailed description of the invention]

【0001】

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a four-wheel drive vehicle equipped with a so-called horizontal engine whose crankshaft extends in the left-right direction of the vehicle body.

【0002】

[Prior Art] Generally, as a four-wheel drive vehicle,
The engine is arranged so that its crankshaft extends in the longitudinal direction of the vehicle body, the transmission is arranged so that its input shaft and output shaft extend in the longitudinal direction of the vehicle body, and a transfer is added to the transmission. It is known that a propeller shaft for the front wheels and a propeller shaft for the rear wheels divide the driving force of the engine into two and transmit it to a front differential and a rear differential, thereby driving four wheels on the front, rear, left and right sides.

[0003] However, four-wheel drive vehicles equipped with such vertically mounted engines have the problem of not being able to provide a large interior space.
In recent years, several four-wheel drive vehicles equipped with transverse engines that do not have such problems have been proposed.

[0004] For example, a center differential composed of a planetary gear mechanism is arranged coaxially with a front differential, and the output from the transmission is received by the pinion carrier of the center differential, and the ring gear or sun gear of the center differential is used to drive the rear wheels. The one that outputs to one of a pair of bevel gears that transmit driving force to the shaft (see Japanese Patent Application Laid-Open No. 154328/1983), the output from the transmission is received by the ring gear of the center differential, and one pair is output from the pinion carrier of the center differential. There is one that outputs to one side of the bevel gear (see Japanese Patent Laid-Open No. 57-41216).

【0005】

[Problems to be Solved by the Invention] Incidentally, the transmission, center differential, and front differential in the above-mentioned four-wheel drive vehicle constitute a power transmission path from the engine to each wheel, and it is desirable to place these devices as close to each other as possible. This is preferable because the power transmission path can be simplified and power transmission loss can be reduced. However, in a layout in which the center differential is arranged coaxially with the front differential as in the conventional layout, there are some limitations to the reduction of the power transmission loss.

[0006] Therefore, instead of arranging the center differential coaxially with the front differential, if the center differential is laid out with its axis offset from the front differential, the center differential and front differential can be easily placed closer to the transmission. It can be achieved.

[0007] However, in that case, in the above layout, there is interference in the radial direction between the front differential and the center differential, which are arranged on different axes.
There is a problem that the degree of freedom in layout is reduced.

[0008] The present invention has been made in view of this point, and its purpose is to specify the horizontal layout between the two center differentials when they are laid out with their axes offset, The purpose is to increase the degree of freedom in layout by arranging a front differential and a center differential close to each other while suppressing interference between the two in the radial direction.

【0009】

[Means for Solving the Problems] In order to achieve the above object, the present invention basically arranges a bevel gear for transmitting power from the center differential to the rear wheels coaxially with the center differential, and We decided to place them on the left and right sides relative to the position of the gear that transmits power between both differentials.

[0010] Specifically, in the present invention, a four-wheel drive vehicle includes an engine whose crankshaft is arranged to extend in the left-right direction of the vehicle body, and a transmission whose input shaft and output shaft are arranged in the left-right direction of the vehicle body. a center differential that receives power from the output shaft of the transmission and distributes the power to the front wheels and the rear wheels;
The vehicle is equipped with a front differential that receives power from the center differential and distributes the power to the left and right front wheels.

[0011] The center differential and the front differential are arranged on a separate shaft, and a drive side bevel gear that transmits power to the rear wheels is provided on a shaft that extends coaxially with the center differential to the left and right center of the vehicle body. A driven bevel gear provided at one end of a propeller shaft extending in the longitudinal direction of the vehicle body is meshed with the gear.

[0012] The center differential and front differential are
Both are arranged on the transmission side with respect to the propeller shaft, and are separated in the left and right direction of the vehicle body at the position of the drive gear that transmits power from the center differential to the front differential.

【0013】

[Function] As a result, in the present invention, since the center differential and front differential are arranged on separate axes, these differentials can be brought together closer to the transmission, simplifying the power transmission path and reducing power transmission loss. can be reduced. In addition, the center differential and front differential are arranged separately in the left and right direction of the vehicle, with the position of the drive gear that transmits power from the center differential to the front differential as the boundary, so even if the front differential is brought close to the center differential, both differentials will be radially opposite to each other. There is no directional interference, and both differentials can be compactly assembled, and the degree of freedom in their arrangement layout can be increased.

[0014] Furthermore, a drive-side bevel gear that transmits power to the rear wheels is provided on a shaft that extends coaxially with the center differential to the left-right center of the vehicle body, and a driven-side bevel gear that transmits power to the rear wheels is provided on the drive-side bevel gear. Since the gears are meshed, the propeller shaft will be located in the center of the left and right sides of the vehicle. Since the center differential and front differential are both located on the transmission side of the propeller shaft, the transmission, center differential, and front differential are closer to each other, reducing power transmission loss by shortening the power transmission path. can be achieved more effectively.

【0015】

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

Embodiment 1 FIGS. 1 and 2 show Embodiment 1 of the present invention, in which 1 is an engine, and a crankshaft 2 is connected to the front right side of the vehicle body.
are arranged so as to extend in the left and right direction of the vehicle body.
Reference numeral 3 denotes a transmission arranged on the left side of the front of the vehicle body so as to be lined up on the left and right with the engine 1 at approximately the left and right center position of the vehicle body. An input shaft 6 connected to the crankshaft 2 via a clutch means 5, and an output shaft 8 connected to a center differential 7.
are located on the left and right sides of the vehicle.

[0017] The input shaft 6 includes, from the clutch means 5 side, a first speed gear 9, a reverse gear 10, a second speed gear 11, a third speed gear 12, and a fourth speed gear 1.
3 are fixed in order. On the other hand, the output shaft 8 has
Gears 14, 15, 16, 17, 18 and a drive gear 19 that mesh with the gears 9, 10, 11, 12, 13, respectively, and a drive gear 19 are fixedly installed, and are synchronized between the gear 14, the gears 15, 17, and the gear 18. Mechanism 2
0 and 21 are arranged.

[0018] The center differential 7 includes a ring gear 22 as an input gear that directly meshes with the drive gear 19 of the output shaft 8 of the transmission 3 and is driven while decelerating the power from the output shaft 8, and a pinion carrier 23. The planetary gear mechanism includes a planetary pinion 24 as one of the output gears that is supported and meshes with the ring gear 22, and a sun gear 25 as one of the output gears that meshes with the planetary pinion 24. The planetary pinion 24 is a double pinion type consisting of a pair of pinions 26 and 27 that mesh with each other, one pinion 26 is connected to the ring gear 22, and the other pinion 27 is connected to the sun gear 2.
5 are interlocked with each other.

[0019] Reference numeral 28 denotes a front differential consisting of a bevel gear mechanism, and its axis is offset from the center differential 7. This front differential 2
A transmission gear 30 is integrally provided on the right end of the outer periphery of the front differential case 29 of No. 8, and the transmission gear 30 is
It meshes with a drive gear 31 that is coaxial with the sun gear 25 of the center differential 7 and integrally connected to the left side thereof. Therefore, center differential 7 and front differential 2
8 are arranged so as to be separated from each other in the left and right direction of the vehicle body, with the position a of the drive gear 31 transmitting power from the center differential 7 to the front differential 28 as the boundary. Also, inside the differential case 29 of the front differential 28, a pair of bevel gears 33 are disposed opposite to each other by a short axis 32 in the longitudinal direction of the vehicle body.
34, and another pair of bevel gears 3 disposed opposite to each other on the left and right so as to mesh with the pair of bevel gears 33, 34.
A bevel gear group consisting of 5 and 36 is provided.

[0020] Joints 39, 40 are provided at the outer ends of the linking mechanisms 37, 38 of the pair of left and right bevel gears 35, 36.
One end of the front wheel drive shafts 41, 42 is connected via another joint 43, 44 to the other end of the front wheel drive shaft 41, 42.
are connected.

[0021] Pinion carrier 23 of center differential 7
The first shaft 47 formed integrally with the center differential 7
At the opposite end of the drive gear 31 with respect to
It is connected to a second shaft 49 via a connecting portion 48 so as to be able to rotate independently. A 2-4 switching sleeve 50 is spline-fitted to the connecting portion between the shafts 47 and 49 so as to be movable in the axial direction. This 2-4 switching sleeve 50 is operated by an operation means (not shown).
It is designed to move between a four-wheel drive position where both shafts 47 and 49 are connected and rotated synchronously, and a two-wheel drive position where only the first shaft 47 is spline-fitted. In the two-wheel drive position, the connection between the rear differential 51 and both rear wheels 52 and 53 is released, and the first shaft 4
7 and both rear wheels 52, 53 are designed not to move.

[0022] Further, the second shaft 49 extends to the left and right center of the vehicle body, and a drive side bevel gear 54 which is coaxial with the center differential 7 is fitted and fixed to this shaft 49. A driven bevel gear 57 provided at the front end of the shaft 55 via a joint 56
are interlocking. These pair of bevel gears 54,
57, driving force is transmitted to rear wheel drive shafts 58, 59. Therefore, the propeller shaft 55 is located at the left-right center of the vehicle body, and the center differential 7 and the front differential 28 are both located on the transmission 3 side (left side of the vehicle body) with respect to the propeller shaft 55.

[0023] The rear end of the propeller shaft 55 is connected to the bevel gear 6 of the rear differential 51 via a joint 60.
1 are connected. A large bevel gear 64 that supports a pair of bevel gears 62 and 63 meshes with this bevel gear 61, and another pair of bevel gears 65 and 66 are arranged oppositely on the left and right so as to mesh with the bevel gears 62 and 63. ing. One end of rear wheel drive shafts 58, 59 is connected to the left and right bevel gears 65, 66 via joints 67, 68, and the left and right rear wheels are connected to the other end of the drive shafts 58, 59 via joints 69, 70. 52, 53
are connected.

[0024] A differential sleeve 71 is movably spline-fitted to the first shaft 47 formed integrally with the pinion carrier 23 on the side opposite to the 2-4 switching sleeve 50 with respect to the center differential 7. This differential sleeve 71 is moved by an operation means (not shown) into an engagement position where it engages with an engagement portion 72 formed integrally with the sun gear 25 to fix the sun gear 25, and an engagement position where it does not engage with the engagement portion 72. 1st to
It is adapted to move in the axial direction between a non-engaging position in which it engages only with the shaft 47. Therefore, if the differential sleeve 71 is set to the above-mentioned engagement position,
The center differential 7 is fixed and cannot be differentially operated. For example, when one wheel is idling on rough terrain such as a muddy road, it prevents the driving force from escaping through this idling wheel and maintains a proper balance between all wheels. This means that the driving force can be distributed.

[0025] With the above configuration, engine 1
The driving force output from the clutch is inputted to the input shaft 6 of the transmission 3 via the clutch means 5.
The gear is changed as appropriate and output from the drive gear 31 of the output shaft 8 to the ring gear 22 of the center differential 7.

[0026] The driving force input to the ring gear 22 is distributed to the pinion carrier 23 that supports the planetary pinion 24 and the sun gear 25. The center differential 7 functions as a differential device and is capable of absorbing and alleviating the rotational speed difference between the pinion carrier 23 that drives the front differential 28 and the sun gear 25 that drives the rear differential 51.

[0027] Thus, the driving force distributed and transmitted to the sun gear 25 is transmitted to the short shaft 32 of the front differential case 29 via the drive gear 31 that is integrated with the sun gear 25.
The transmission is distributed to the left and right by a pair of bevel gears 33, 34 supported by the short shaft 32, and another pair of bevel gears 35, 36 meshing with these gears, whereby the left and right front wheels 45, 46 is driven.

[0028] On the other hand, when the 2-4 switching sleeve 50 connects the first shaft 47 and the second shaft 49 in the engagement position, the driving force distributed and transmitted to the pinion carrier 23 is 47 and the 2-4 switching sleeve 50, the second shaft 49 is rotationally driven. As a result, the drive side bevel gear 54 fixed to the second shaft 49 rotates and engages with the driven side bevel gear 57, passing through the propeller shaft 55 to the rear differential 51.
It is then distributed to the left and right to drive the left and right rear wheels 52, 53.

[0029] In this embodiment, the center differential 7 and the front differential 28 have their axes offset and are arranged on different axes, so that both the center differential 7 and the front differential 28
8 can be laid out together close to the transmission 3, the power transmission path from the engine 1 to the wheels can be simplified, and power transmission loss can be reduced.

[0030] Furthermore, the center differential 7 and the front differential 28 are arranged separately in the left-right direction of the vehicle body with the position a of the drive gear 31 transmitting power from the center differential 7 to the front differential 28 as a boundary, so the front differential 28 is Even if the differentials 7 and 28 are laid out close to each other, the differentials 7 and 28 will not interfere with each other in the radial direction. Therefore, both the differentials 7 and 28 can be compactly arranged, and the degree of freedom in their arrangement layout can be increased.

[0031] Furthermore, first and second shafts 47, 49 extend coaxially with the center differential 7 to the left and right center portions of the vehicle body.
A drive side bevel gear 54 that transmits power to the rear wheels 52 and 53 is provided, and a driven side bevel gear 57 connected to the front end of the propeller shaft 55 is provided to the drive side bevel gear 54.
Since the two are in mesh with each other, the propeller shaft 55 can be placed in the center of the left and right sides of the vehicle body. Since both the center differential 7 and the front differential 28 are located closer to the transmission 3 (on the left side of the vehicle body) than the propeller shaft 55 located in the left and right center of the vehicle body, the center differential 7 and the front differential 28 are Proximity to the transmission 3 can be reliably achieved, and the effect of shortening the power transmission path and reducing power transmission loss can be effectively achieved.

Embodiment 2 FIG. 3 shows Embodiment 2 of the present invention, and is an example in which the transmission is equipped with an auxiliary transmission.

[0033] In FIG. 3, the ring gear 22 of the center differential 7 meshes with a gear 83 integrally molded on a shaft 82 constituting an auxiliary transmission 81, and a low speed gear 84 and a high speed gear are connected to the shaft 82 from the gear 83 side. 8
5 are fitted and fixed in order, and a synchronizing mechanism 86 is interposed between the two gears 84 and 85. Gears 87 and 88 that mesh with the low speed gear 84 and high speed gear 85
is formed integrally with the output shaft 8 of the transmission 3.

[0034] With this, the main transmission side is shifted in four stages, 1st speed, 2nd speed, 3rd speed, and 4th speed, while the auxiliary transmission side is shifted in 2 stages of high speed and low speed, respectively. , the overall speed will be changed in eight steps. This embodiment also provides the same effects as those of the first embodiment.

[0035] In the above embodiment, the front differential 28 is disposed on the opposite side of the propeller shaft 55 with respect to the center differential 7, but in the present invention, both the differentials 7,
This also includes a layout embodiment in which the position of the front differential 28 is reversed and the front differential 28 is placed closer to the propeller shaft 5 than the center differential 7. Also, of course, engine 1 and transmission 3
It can also be applied to a layout in which the left and right arrangement is reversed from that of each of the above embodiments.

[0036] Further, in the above embodiment, the transmission gear 30 provided on the outer periphery of the front differential case 29 and the sun gear 25 of the center differential 7 mesh with each other, while the drive side bevel gear 54 for driving the rear wheels is integrated with the pinion carrier 23 of the center differential 7. However, it is also possible to mesh the transmission gear 30 and the pinion carrier 23 of the center differential 7 to integrally fix the drive side bevel gear 54 to the sun gear 25 of the center differential 7. good.

[0037] Further, in the above embodiment, a case has been described in which the engine 1 is disposed at the front of the vehicle body, but it goes without saying that the present invention can also be applied to a case where the engine is disposed at the rear of the vehicle body.

【0038】

[Effects of the Invention] As described above, the present invention offsets the center differential and front differential in a four-wheel drive vehicle on separate axes, and distributes them in the left-right direction of the vehicle body using the position of the gear between the two differentials as a boundary. In addition, by placing both differentials on the transmission side with respect to the propeller shaft located in the left and right center of the vehicle body, the center differential and front differential can be placed closer to the transmission, simplifying the power transmission path and improving power transmission. In addition to reducing loss, it is possible to eliminate interference in the radial direction when bringing the front differential and the center differential closer together, thereby making it possible to make the layout more compact and improve its degree of freedom.

[Brief explanation of drawings]

FIG. 1 is a diagram schematically showing, in skeleton form, a drive system of a four-wheel drive vehicle according to a first embodiment of the present invention.

FIG. 2 is a sectional view specifically showing the main parts of the drive system.

3 is a diagram corresponding to FIG. 2 showing Example 2. FIG.

[Explanation of symbols]

1...Engine 2...Crankshaft 3...Transmission 6...Input shaft 7...Center differential 8...Output shaft 22...Ring gear 23...Pinion carrier 24...Planetary pinion 25...Sun gear 28...Front differential 29...Front differential case 30...Transmission gear 31... Drive gear 41, 42...Front wheel drive shaft 47...First axis 49...Second axis 50...2-4 switching sleeve 54... Drive side bevel gear 55...propeller shaft 57...Driven bevel gear 58, 59...Rear wheel drive shaft 71...Defroc sleeve 81...Sub-transmission.

Claims (1)

[Claims] Claim 1: An engine arranged so that a crankshaft extends in the left-right direction of the vehicle body, a transmission in which an input shaft and an output shaft are arranged in the left-right direction of the vehicle body, and power is output from the output shaft of the transmission. The vehicle is equipped with a center differential that receives power from the center differential and distributes power to the front wheels and rear wheels, and a front differential that receives power from the center differential and distributes the power to the left and right front wheels, and the center differential and front differential are on separate shafts. A drive-side bevel gear that transmits power to the rear wheels is provided on a shaft that extends coaxially with the center differential to the left-right center of the vehicle body, and the drive-side bevel gear has one end of a propeller shaft extending in the longitudinal direction of the vehicle body. The driven side bevel gear provided on the front differential is meshed with the center differential and the front differential, and the center differential and the front differential are both arranged on the transmission side with respect to the propeller shaft, and the center differential and the front differential are arranged on the transmission side with respect to the propeller shaft. A four-wheel drive vehicle that is characterized by being arranged in left and right directions.