JPS59145627A - Four-wheel-drive car - Google Patents

Abstract

PURPOSE:To facilitate to pull out a car from the sands and the like by providing a lock means on a differential mechanism for left and right wheels to accord the numbers of revolutions of left and right wheels connected thereto for according the numbers of revolutions of left and right wheels by the operation of the lock means when four wheels are driven. CONSTITUTION:In a front wheel differential mechanism 39 to which the power of an engine is transmitted via a 2/4 wheel switching mechanism and an input shaft 40 at the time of 4-wheel driving, clutch teeth 56 and 57 are respectively provided on the first shaft 52 and the second shaft 53 constructing a drive shaft 50 on one side. Besides, a clutch tooth 58 is provided on a DIF-case 44 near to the clutch tooth 56, and the clutch teeth 56 and 57; 56 and 58 can be connected by coupling seeves 59 and 60 respectively. When four wheels are driven, both teeth 56 and 57 are connected by the sleeve 59 to give the differential function to left and right front wheels 54 and 55. When one front wheel is caught in the sands and the like at the time of four-wheel driving, both teeth 56 and 58 are connected by the above-mentioned sleeve 60 constructing a lock means 62 for stopping the differential function.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a differential mechanism for left and right wheels of a four-wheel drive vehicle, particularly a part-time four-wheel drive vehicle.

In general, in part-time four-wheel drive vehicles, in order to improve fuel efficiency when driving two-wheel drive, it is desirable to install a free-running machine (Jilt), which separates the wheels to which no driving force is applied from the drive shaft. A four-wheel drive vehicle having such a free running function is known as described in US Pat. No. 4.34L281.

Fig. 1 is a diagram showing a front wheel differential mechanism 1 of a four-wheel drive vehicle described in the above-mentioned US patent specification. The driving force of the engine is applied to the rear wheels by a rear wheel propeller shaft, a rear wheel differential mechanism, etc., and is also transmitted through a front wheel propeller shaft, a front wheel differential mechanism 1, and a pair of drive shafts 2.3. The power is also transmitted to a pair of front wheels 4.5. Here, the drive shaft 3 includes a first shaft 8 spline-coupled to the side gear 6 and protruding from the differential case 7, and a second shaft 9 rotatably inserted into the first shaft 8 via a needle bearing and connected to the front wheels 6. Clutch teeth 10.11 are formed close to each other on the first and second shafts 8.9. The coupling sleeve 12 is in the state shown in FIG. 1 during two-wheel drive, and the first shaft 8 and the second
Since they are separated from the shaft 9, the rotation of the front wheels 4 and drive shaft 2 is transmitted only to the side gear 6 and first shaft 8 via the side gear 13 and pinion gear 14, and the differential case 7, pinion mate shaft 15, etc. do not rotate. . Therefore, the free running function is exhibited, and it is possible to improve fuel efficiency and the like. however,
During four-wheel drive, the coupling sleeve 12 connects the clutch teeth 10.11, so the rotational speed of the side gear 13.6 differs depending on the difference in the load applied to the left and right front wheels 4.5, and the front wheel differential mechanism 1 changes accordingly. Demonstrates dynamic functions at all times.

Generally, four-wheel drive vehicles are intended for driving on rough terrain.
On rough terrain, there is a high possibility that either the left or right front wheels 4 or 5 will run into sand or mud. In such a case, in order to make it easier for a four-wheel drive vehicle to escape from a sandy area, the differential function of the front wheel differential mechanism 1 is suppressed or stopped, and the front wheels other than front wheels 4 or 5 that have entered the sandy area are It is desirable to apply a driving force to 5 or 4.

A limited slip differential 16 shown in FIG. 2 is generally known as a mechanism for suppressing the differential function of a differential mechanism.

This limited slip differential 16 is the second
It is constructed as shown in the figure, and is capable of transmitting 1-lux, which is several times the torque transmitted to the wheel that is spinning, to the wheel that is not spinning. That is, when one pressure ring 17 tries to rotate in a certain direction, the pinion mate shaft 19 supported by the ■-shaped groove 18 moves along the slope 20 defining the V-shaped groove 18 and the pinion no. - the shaft 19 is partially omitted), and the pressure rings 17, 21 move away from each other. Therefore, the friction disc 22 and the friction plate 23 are pressed together, and torque can be transmitted to the wheels that do not spin.

However, such a mitenodorisop differential 16 has a complex structure and has the function of suppressing its differential function even during normal driving, which reduces the tendency of understeer when a vehicle equipped with it turns. It has a strengthening feature.

Therefore, as the front wheel differential mechanism 1 of a four-wheel drive vehicle,
If either front wheel 4 or 5 enters a sandy area, etc., the differential function of the front wheel differential mechanism 1 is suppressed or stopped, and the differential function is fully activated during normal driving, especially when turning. It is desirable to be able to demonstrate this.

This invention has been made in view of the above-mentioned needs, and is designed to match the rotational speeds of the left and right wheels connected to the left and right wheel differential mechanism connected to the output shaft that is separated from the input shaft during two-wheel running. By providing a locking means and switching the locking means to the locking position when the four axes are stopped, the number of rotations of the left and right wheels can be matched, resulting in a simple and compact structure that meets the above requirements.
The purpose is to provide wheel drive vehicles.

Hereinafter, this invention will be explained based on the drawings.

FIG. 3 shows a first embodiment of the present invention, and the configuration will be explained first. Reference numeral 25 is a transfer having a shallow structure for switching from two wheels to four wheels inside, and this transfer 25 can be operated manually after the rotation of the crankshaft of the engine 26 is changed by a 1-transmission transmission 27.Transfer 2
5 has a pair of output shafts 28 and 29, and one output shaft 28 is connected to a rear wheel differential mechanism 32 via a universal joint 30 and a rear propeller shaft 31. Since the output shaft 28 is always connected to the crankshaft via the transmission 27, the drive shaft 33.3
Rear wheel 35.3 connected to differential mechanism 32 via 4
6 is constantly provided with driving force. On the other hand, the other output shaft 2
9 is the input shaft 4 of the front wheel differential mechanism 39 via the universal join i.37 and the front wheel propeller shaft 38.
0, and when the two-wheel to four-wheel switching mechanism in the transfer 25 is switched to the two-wheel drive position by a switching lever (not shown), the rotation of the crankshaft is not transmitted to the output shaft 29.

On the other hand, when the two-wheel to four-wheel switching mechanism is switched to the four-wheel drive position, the rotation of the crankshaft is transmitted to the output shaft 29. As shown in detail in FIG. 4, the front wheel differential mechanism 39 includes an input shaft 40 extending in the longitudinal direction of the vehicle and rotatably supported by a case 41, and a pinion gear 4 fixed to the input shaft 40.
2 and a differential case 44 connected to the input shaft 40 via a ring gear 43, and a pinion mate shaft 45 fixed to the differential case 44.
It has a pinion gear 46 rotatably supported by the pinion gear 46, a pair of side gears 47.48 meshing with the pinion gear 46, and a pair of drive shafts 49.50 connected to the side gears 4 and 47.48, respectively. . These pinion mate shaft 45, pinion gear 46 and side gear 47.
48 constitutes a differential gear set 51 as a whole. The drive shafts 49 and 50 are rotatably supported by the case 41 and extend in one direction of the vehicle, and the drive shaft 50 is connected to the side gear 48.
The first shaft 52 is spline-coupled to the first shaft 52, and the second shaft 53 is rotatably supported by the first shaft 52 via a needle hair ring. Furthermore, front wheels 54.55 are connected to the drive shafts 49.50, respectively. First axis 52
and the second shaft 53 have clutch teeth 56.5 adjacent to each other.
7 is formed, and the clutch teeth 56 are also close to clutch teeth 58 formed on the differential case 44. The clutch teeth 56 , 57 can be connected by a coupling sleeve 59 and the clutch teeth 56 , 58 can be connected by a cambling sleeve 60 . The compression sleeves 59, 60 can be switched into a connected position and a disconnected position, respectively, by means of a separate switching mechanism (not shown). The clutch teeth 56,57 and the coupling sleeve 59 together constitute a free-running means 6I, and the clutch teeth 56,58 and the coupling sleeve 60 together constitute a locking means 62.

Next, the effect will be explained. When a four-wheel drive vehicle runs on a paved road, etc. with two-wheel drive, the free running means 6
1 and the locking means 62 are both switched to the disconnected position shown in FIG. The rotation of the shaft is transmitted only to the rear wheels 35, 36, and the output shaft 29 does not rotate. On the other hand, since the free running means 61 also separates the first shaft 52 and the second shaft 53, the rotation of the front wheel 55 is not transmitted to the first shaft 52, and the rotation of the front wheel 54 is transmitted from the drive shaft 49 to the side gear 47 and pinion gear 46. through the side gear 48 and the first shaft 5
2 and the differential case 44 does not rotate. Therefore, the input shaft 40 etc. connected to the differential case 44 do not rotate, and a so-called free running function is achieved, so the power required to rotate the differential case 44 etc. is not required, and the fuel efficiency of the engine 26 improves. .

Next, when the four-wheel drive vehicle travels in four-wheel drive on rough terrain, not only the two-wheel-to-four-wheel switching mechanism of the transfer 25 is switched to the four-wheel drive position, but also the free running means 61 is moved to the connected position. can be switched to Note that the locking means 62
is still switched to the disconnection position. Therefore, the rotation of the crankshaft of the engine 26 is transmitted to the output shaft 28.2 via the transmission 27 and the transfer 25.
9, the front wheel is 54.5 instead of the rear wheel 35.36
5 is also provided with driving force. Here, when the four-wheel T% vehicle turns, not only the rear wheel differential mechanism 3 but also the front wheel differential mechanism 39 exhibits a sufficient differential function in response to the load applied to the front wheels 54,55. Therefore, the front wheel differential mechanism 39 will not cause the understeer to expand or expand.

Next, if one of the front wheels 54 or 55 enters sand or the like while driving in four-wheel drive, the coupling sleeve 60 connects the clutches #35G and 58, and the locking means 62 is moved to the connected position ( (lock position). As a result, the differential function of the front wheel differential mechanism 39 is stopped. Therefore, the rotation of the output shaft 29 is transmitted to the first shaft 52 via the input shaft 40, pinion gear 42, ring gear 43, and differential case 44, and is also transmitted to the site gear 4 via the sight gear 48 and pinion gear 46.
7, and is transmitted to the front wheels 54.7 via the drive shaft 49.50.
55 rotates at a constant speed. In this way, the front wheel differential mechanism 3
9 stops the differential function, the four-wheel drive vehicle can continue to run even if one of the front wheels 54 or 55 runs into sand or the like. Furthermore, the locking means 62 can have a simpler structure than the limited slip differential 16 by forming the clutch teeth 58 on the differential case 44 and connecting the clutch teeth 56, 58 with the coupling sleeve 60.

FIG. 5 is a diagram showing a second embodiment of the present invention, and the same components as those in the first embodiment are designated by the same reference numerals and explanations thereof will be omitted. 64 is a compling sleeve that engages with the clutch teeth 57, and when the compling sleeve 64 engages only with the clutch teeth 57 as shown in FIG. 5, a free running function is exhibited. On the other hand, the compulsory sleeve 64 is slid by a common switching mechanism (not shown), and the clutch teeth 5 are moved as shown in FIG.
When 6.57 is connected, the rotation of the first shaft 52 can be transmitted to the second shaft 53, and four-wheel drive is possible. When the compression sleeve 64 is further slid to connect the clutch teeth 56, 57, 58 with each other as shown in FIG.
Since the front wheel differential mechanism 39 stops the differential function, even if any of the front wheels 54, 55 enters a sandy area, it can easily escape. The coupling sleeve 64 has clutch teeth 56.5
7 constitutes a free running means 65, and together with the clutch teeth 56, 58 constitutes a locking means 66.

As described above, in the second embodiment, by switching one coupling sleeve 64 using a common switching mechanism, the free running function and the differential function can be stopped, making the structure even simpler than the first embodiment. be able to.

As described above, according to the present invention, the rotation of the input shaft of a four-wheel drive vehicle is selectively transmitted to one or both of a pair of output shafts each connected to a differential mechanism for left and right wheels. The differential mechanism for the left and right axes is connected to the output shaft, which is separated from the input shaft when the two axes are stopped, and the free running means and the rotation of the left and right wheels connected thereto are equipped with a two-wheel to four-wheel switching mechanism. It has a locking means that matches the number of wheels, and when the vehicle is in four-wheel drive, the locking means can be switched to the locked position so that the rotational speed of the left and right wheels can be matched, making it easy to escape even if one of the left or right wheels falls into sand, etc. In addition, a simple and compact four-wheel drive device is obtained in which the understeer does not increase due to the differential mechanism for left and right wheels.

[Brief explanation of the drawing]

Fig. 1 is a partial cross-sectional plan view of a conventional differential mechanism for four-wheel drive vehicles, Fig. 2 is a front cross-sectional view of a limited slip differential, and Fig. 3 is a plan view showing a first embodiment of the present invention. , FIG. 4 is an enlarged sectional view of the front wheel differential mechanism shown in FIG. 3,
FIGS. 5, 6 and 7 are plan sectional views showing a second embodiment of the invention. 28.29---1 pair of output shafts, 32.39---Differential mechanism for left and right wheels, 4]---One case, 49.50---1-=drive shaft, 51--- m-differential gear set, 52--11 first shaft, 53--12nd shaft, 5G, 57.58--Clutch teeth, 59--
--Second coupling sleeve, 60--1--First coupling sleeve, 61.65.--11 Free-running means, 62.6G--Lock means, 64--1 Kanobringue leaf. Figure 5 39 Figure 6 9

Claims (3)

[Claims] (1) Equipped with a 2-wheel-4-wheel switching mechanism that can selectively transmit the rotation of the input shaft to either or both of a pair of output shafts each connected to a differential mechanism for left and right wheels. In a four-wheel drive vehicle, the differential mechanism for left and right wheels connected to an output shaft that is disconnected from the input shaft when the two wheels are driven has a free running means, and the left and right wheels that are connected to the output shaft that are disconnected from the input shaft when the two wheels are driven. A locking means is provided in the differential mechanism to match the rotational speeds of the left and right wheels connected to the vehicle, and the locking means can be switched to the lock position during four-wheel drive so that the rotational speeds of the left and right wheels can be matched. Features 4 wheel drive army. (2) The differential mechanism for left and right wheels connected to the output shaft that is separated from the input shaft when two wheels are running has a case connected to the output shaft and formed with clutch teeth, and a case that connects one end to the left and right wheels and the other end to the left and right wheels. A pair of drive shafts each connected to a differential gear set that produces a difference in rotational speed between the left and right wheels according to the load on the left and right wheels,
One of the pair of drive shafts has a first shaft connected to a differential gear set and formed with clutch teeth, and a second shaft connected to one of the left and right wheels and formed with clutch teeth. It is characterized by comprising a first campling sleeve capable of connecting the clutch teeth and the clutch teeth of the case, and a second compling sleeve capable of connecting the clutch teeth of the first shaft and the clutch teeth of the second shaft. A four-wheel drive vehicle according to claim 1. (3) The differential mechanism for left and right wheels connected to the output shaft that is separated from the input shaft when the two wheels are running has a case connected to the output shaft and formed with clutch teeth, and a case that connects one end to the left and right wheels and the other end to the left and right wheels. a pair of drive shafts each connected to a differential gear set that produces a difference in rotational speed between the left and right wheels in response to a load on the left and right wheels; one of the pair of drive shafts is connected to the differential gear set; It has a first shaft on which clutch teeth are formed, and a second shaft connected to one of the left and right wheels and on which clutch teeth are formed, and the clutch teeth on the second shaft are connected to the clutch teeth on the first shaft or the first shaft. The four-wheel drive vehicle according to claim 1, further comprising a compression sleeve connectable to the clutch teeth and the clutch teeth of the gate.