JPH01114527A - Torque split type four-wheel-drive vehicle - Google Patents

Abstract

PURPOSE:To obtain the compact constitution of a whole device by installing an extension part case in the rear part of a transmission and installing a center diff on the front side of a center partitioning wall and installing a hydraulic clutch for a torque split device in the rear part of the center partitioning wall and introducing the hydraulic oil in the transmission into the inside of the hydraulic clutch. CONSTITUTION:An automatic transmission case 2 is installed behind a torque converter 10 equipped with a lock-up device, and an extension part case 4 is installed at the rear part, and a center diff 30 is arranged on the front side of a center partitioning wall, and the hydraulic clutch 50 of a torque split device is arranged on the rear side. A rear drive shaft 31 arranged behind the center diff, and a front drive shaft 22 is installed in front of the center diff through reduction gears 36 and 37, and each shaft is connected with the clutch 50 through reduction gears 46 and 47 and a bypass shaft 41. The lubricating oil in the automatic transmission case is introduced into the extension part case 4. Therefore, the torque split device can be assembled in compact form into the transmission case part of a 4WD vehicle.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a full-time four-wheel drive vehicle equipped with a center differential device capable of torque splitting, and more particularly to a torque splitting device and its lubrication structure.

[Conventional technology]

Conventionally, regarding a torque split four-wheel drive vehicle, there is one disclosed in Japanese Patent Application Laid-Open No. 62-203825 by the applicant of the present invention. Here, a center differential device and a torque split device are arranged at the rear of the transmission, and the center differential device distributes the transmission output to the front and rear wheels. The torque split device connects a bypass shaft with a hydraulic clutch to the center differential device using two sets of gears, and transfers the torque transmitted by the hydraulic clutch from one of the front and rear wheels to the other, thereby increasing the torque of the front and rear wheels. Active split control is shown.

[Problems to be solved by the invention]

By the way, in the conventional prior art described above, the drive system is only shown in a skeleton manner, and it is necessary to devise a structure when realizing it. Furthermore, since the center differential device and the hydraulic clutch are arranged adjacent to each other, it is necessary to clarify the lubrication and hydraulic control system for the hydraulic clutch. In view of these points, it is an object of the present invention to provide a torque split four-wheel drive vehicle in which the connection structure between the center differential device and the torque split device is strengthened and sufficient lubrication is achieved.

[Means to solve the problem]

In order to achieve the above object, the present invention provides an extension case connected to the rear part of a transmission via a torque split case, a center differential device on one side of the partition wall inside the torque split case, and a torque split device on the other side. A hydraulic clutch of the device is disposed, and the center differential device is arranged between a transmission output shaft and a rear drive shaft coaxial therewith, and configured to transmit power to the front drive shaft via the rear drive shaft and a reduction gear. However, in the above torque split device, one inner shaft of the bypass shaft is directly connected to the front drive shaft, the other outer shaft is separated and placed on the same axis, and a hydraulic clutch is provided between the two, and the outer shaft is connected to the front drive shaft. is connected to the rear drive shaft via a reduction gear, and is configured to provide a forced lubrication system from the transmission output shaft to the bearing section of the center differential device, and from the bypass shaft to the hydraulic clutch and bearing section. .

[For production]

Based on the above configuration, the center differential device and the torque split device are compactly housed and arranged inside the torque split case, and each part is reliably lubricated by the oil inside the case and the forced lubrication system, thereby performing torque split control.

【Example】

Hereinafter, an actual example of the present invention will be explained based on the drawings. Referring to FIG. 1, when the present invention is applied to a vertical type in combination with an automatic transmission, a transmission case 2 is connected to the rear of a differential box case 1 on the engine side via a partition wall 3. A torque split case 4 and an extension case 5 are further connected to the rear of the transmission case 2 housing the automatic transmission. A lock-up torque converter 10 is disposed at the front inside the differential box case 1, a front differential device 25 is disposed at the lower part between the automatic transmission and the torque converter, and an automatic transmission 1 is disposed inside the transmission case 2.
120, and a control valve body 26 is provided below it. Furthermore, a center differential device 30 and a torque split device 40 are housed inside the torque split case 4. Reference numeral 11 indicates a crankshaft of the engine, and this crankshaft 11 is connected to a converter cover 13 via a drive plate 12, and a pump impeller 10a of the torque converter 10 is integrally provided to this converter cover 13. A stator 10c of the torque converter 10 is supported by a one-way clutch 14, and a turbine runner 10b is connected to an input shaft 16 via a turbine hub 15. An oil pump 17 is attached to the partition wall 3, and the oil pump 17 is connected to the converter cover 13 via a pump drive shaft 18, so that the oil pump 17 is constantly driven. Further, a piston 19a of a lock-up clutch 19 is attached to the turbine hub 15, and the piston 19a can be mechanically inserted into the converter cover 13. Automatic transmission [12G is a planetary gear (not shown). It consists of a clutch, a brake, etc., and automatically shifts the power of the input shaft 16 to an output shaft 21 installed at the rear on the same axis.
Outputs shifting power to. A front drive shaft 22 from a center differential device 30 is arranged in parallel directly below the automatic transmission 20, and a drive pinion gear 23 at the front end of this front drive shaft 22 is connected to a crown gear 24 of a front differential device 25 inside the differential box case 1. The transmission is configured to mesh with the left and right rear and front wheels. As detailed in FIG. 2, the center differential device 30 is of a planetary gear type in order to unequal initial torque distribution between the front and rear wheels, and includes a sun gear 30a, a ring gear 30b, a pinion 30c, and a carrier 30d. Here, the end 21a of the output shaft 21 is connected to the torque split case 4.
A rear drive shaft 31 is disposed coaxially with the rear drive shaft 31, and a sun gear 30a is formed at an end flange 31a of the rear drive shaft 31. Further, a gear member 32 is rotatably attached to the output shaft end portion 21a and is rotatably supported by a needle 33, and a ring gear 301) is formed inside the stepped cylindrical portion 32a of the gear member 32. The carrier 30d is spline-coupled to the output shaft 21 between the gear member 32 and the flange 31a, and is secured to the output shaft 21 with a nut 34 to prevent the gear member 32. The carrier 30d and the 7 langes 31a are positioned close to each other via the thrust bearing 35. A reduction drive gear 36 is formed on the gear member 32, and this reduction drive gear 36 meshes with a driven gear 37 integral with the front drive shaft 22 to form a transmission structure, and a parking gear 38 is attached to a portion of this driven gear 37. In the torque split device 40, a clutch inner shaft 41a of a bypass shaft 41 is connected coaxially with a drive shaft 22 by spline connection and fixed with a bolt 42, and the middle of the clutch inner shaft 41a is connected to a partition of the torque split case 4. It is supported by a bearing 43 on the wall 4a. In addition, one end of the clutch outer shaft 41b is fitted into the inner shaft 41a via the needle 44, and the other end is supported by the bearing 45 of the extension case 5, so that the clutch outer shaft 41b is further arranged coaxially, and these inch shafts 41a and 7 A hydraulic clutch 50 is provided between the outer shaft 41b and the outer shaft 41b. On the other hand, a reduction drive gear 46 is spline-coupled to the rear drive shaft 31 and fixed to the rear drive shaft 31 so that it cannot be removed, and this reduction drive gear 46 meshes with a driven gear 47 spline-coupled to the outer shaft 41b. The drive shaft 31 forms a power transmission line bypassing the device 30, and the drive shaft 31 is supported by a bearing 49 at the partition wall 4a and the reduction drive gear 46. The hydraulic clutch 50 includes a hub 5 integral with the inner shaft 41a.
1. It has a large number of plates 53 between both the outer shaft 41b and an integral drum 522, and a piston 54 presses the plates 53 with clutch oil pressure in a piston chamber 55 to variably control clutch torque. Next, the center differential device! f30. Regarding the lubrication of the torque split device 40, the torque split case 4 communicates with the transmission case 2 and contains the same ATF (automatic transmission fluid) oil as the automatic transmission 1fi 20, and the torque split case 4 communicates with the transmission case 2 and contains the same ATF (automatic transmission fluid) oil as the automatic transmission 1fi 20. Reduction gear 36.37,4
6.47, hydraulic clutch 50. Most of the bearings are immersed in this oil or are lubricated by the oil droplets. In addition, the hydraulic clutch 50. Regarding the needle 44, oil from the oil cooler flows from the passage 60 of the extension case 5 into the hole 61 of the inner shaft 41a and the outer shaft 41b, enters the inside of the hub 51 through the needle 44 from the gap between the two, and then flows into the hub 51. 51 holes 62. The plates 53 are forced to lubricate between each other by passing through holes 63 in the drum 52. The lubrication hole 64 of the output shaft 21 passes through the needle 33 of the gear member 32 through small holes 65 and 66, and communicates with the outside through the small hole 68 of the end cap 67.
3, thrust bearing 35, etc., forcibly lubricate. Further, as a hydraulic control system of the hydraulic clutch 50, the side wall surface 5 of the torque split case 4 of the extension case 5
A pulp body 70 is attached to the valve body 70, and an oil passage 71 from the valve body 70 is formed in the outer shaft 41b so that oil can be supplied to the piston chamber 55. Next, the operation of the torque split four-wheel drive vehicle configured as described above will be described. First, when the vehicle is running, the automatic transmission V & 20 is in Drive (D).
When the vehicle is shifted to a driving range such as the above, engine power is input to the automatic transmission 20 via the torque converter 10, and shifting power is output, and this power is transmitted to the carrier 30d of the center differential device 30. Then, the torque is distributed to the front and rear wheels at a torque distribution ratio of, for example, 60:4G by the ring gear 30b and the sangya 30a in accordance with the static load distribution to the wheels of the vehicle. Power beam from ring gear 30b.Dduction gear 36. Driven gear 37. Front drive shaft 22. The power from the sun gear 30a is transmitted to the front wheels via the front differential device 25, etc., and the power from the sun gear 30a is transmitted to the rear wheels via the rear drive shaft 31, etc., resulting in full-time 411a drive running with a seven-way differential. At this time, the hydraulic clutch 50 of the torque split device 40
rotates with a difference in rotation due to the gear ratio between reduction gears 36.37 and 46.47, allowing torque to be transferred to the rear wheels. Therefore, the torque distribution ratio is set in the electronic control system according to the running conditions, and based on this, the torque distribution ratio is set from the pulp body 70 to the oil path 71.
Clutch hydraulic pressure is supplied to the piston chamber 55 of the hydraulic clutch 50 through the piston chamber 55 to transmit torque. Then, this clutch torque transmission is transmitted to the rear drive shaft 3.
1, and thus active torque split control is performed. At this time, the center differential device 30. Each part of the torque split device 40 uses the same ATF as the automatic transmission 5120.
Lubricated with oil. Although one embodiment of the present invention has been described above, the center differential device 730 may be of a bevel gear type, or the inside of the torque split case 4 may be partitioned to lubricate the center differential device 30 with a defoil. Furthermore, it is also possible to apply it to a manual transmission.

【Effect of the invention】

As described above, according to the present invention, in a torque split four-wheel drive vehicle, the center differential device and the torque split device are compactly and firmly assembled inside the torque split case. The shaft and rotating members are reliably supported by needles and bearings, and the rotating members are accurately positioned relative to each other by thrust bearings. The center differential device and torque split device are easily lubricated using the same ATF oil as the automatic transmission.

[Brief explanation of the drawing]

FIG. 1 is an overall sectional view showing an embodiment of the torque split four-wheel drive vehicle of the present invention, and FIG. 2 is an enlarged sectional view of the main parts. 4...torque split case, 4a...partition wall,
20... automatic transmission, 21... output shaft, 22...
Front drive shaft, 30... Center differential device, 3
1...Rear drive shaft, 36.37, 46.47...
- Reduction gear, 40... Torque split device, 41... Bypass shaft, 41a... Inner shaft, 41
b...Outer shaft, 50...Hydraulic clutch, 61°6
4...Forcible lubrication hole patent applicant: Fuji Heavy Industries Co., Ltd. agent, patent attorney: Makoto Kobashi, patent attorney: Susumu Murai, patent attorney

Claims (1)

[Claims] An extension case is connected to the rear of the transmission via a torque split case, a center differential device is installed on one side of the partition wall inside the torque split case, and a hydraulic clutch of the torque split device is installed on the other side. The center differential device is arranged between a transmission output shaft and a rear drive shaft coaxial therewith, and is configured to transmit power to the front drive shaft via the rear drive shaft and a reduction gear, The device directly connects one inner shaft of the bypass shaft to the front drive shaft, and separates the other outer shaft and arranges it coaxially.
A hydraulic clutch is provided between the two, and the outer shaft is connected to the rear drive shaft via a reduction gear, from the transmission output shaft to the bearing part of the center differential device, and from the bypass shaft to the hydraulic clutch and bearing part. A torque split four-wheel drive vehicle characterized by providing a forced lubrication system.