Power distributing apparatus for vehicles

A power distributing apparatus for vehicles includes an input shaft, first and second output shafts, a simple planetary gear set having a carrier operatively connected to the input shaft, a ring gear cooperating with the first output shaft, and a sun gear selectively engaged with the second output shaft, and means for selectively engaging the carrier and the sun gear and for integrally rotating the sun gear and the carrier in the engaging state of the sun gear and the carrier, and for more slowly rotating the sun gear than the carrier in the disengaging state of the sun gear and the carrier.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates generally to a power distributing apparatus 
and more particularly to such an apparatus for vehicles. 
2. Description of the Prior Art 
A conventional power distributing apparatus, such as that employing a 
differential apparatus of first and second output shafts, is constituted 
by a simple planetary gear which is also utilized for an over-drive 
apparatus of first output shaft so as to improve a high speed running 
efficiency, a silent efficiency and a fuel expenses efficiency for 
vehicles, an input shaft and a carrier of simple planetary gear, a ring 
gear of simple planetary gear and the first output shaft, and a sun gear 
of simple planetary gear and the second output shaft are capable of 
selectively cooperating with each other, and when only the first output 
shaft is driven the sun gear of simple planetary gear is fixed to a case. 
When there is no changing between the input shaft and the carrier, the 
ring gear and the first output shaft, and the sun gear and the second 
output shaft by various factors in this apparatus, both of torque 
distributing ratio and over-drive ratio are determined by a ratio of gear 
number. For example, supposing that the gear number of ring gear is 65 and 
the gear number of sun gear is 35, the torque distributing ratio (torque 
of the second output shaft/torque of the first output shaft) becomes 35/65 
and the over-drive ratio (rotational number of the input shaft/rotational 
number of the first output shaft) becomes 0.65. However, it is desirous 
that the torque distributing ratio responds to a load distributing ratio 
of each vehicle shaft and it is generally 30-50/70-50 while the over-drive 
ratio is determined on the basis of the relation between engine output and 
load and is generally 0.8. Accordingly, both the torque distributing ratio 
and the over-drive ratio are not capable of adjusting to an appropriate 
value. 
SUMMARY OF THE INVENTION 
The present invention provides an improved power distributing apparatus for 
vehicles which obviates the drawback of the above-mentioned conventional 
power distributing apparatus. 
The power distributing apparatus for vehicles according to the present 
invention provides a unique and highly simplified power distributing 
apparatus for vehicles. It is capable of adjusting both as to torque 
distributing ratio and as to over-drive ratio to an appropriate value at 
the above-mentioned limiting state, and a sun gear and a carrier are 
voluntarily cooperated to each other and a connecting means for 
integerally rotating the sun gear and the carrier in the engaging state of 
the sun gear and the carrier and for more slowly rotating the sun gear 
than the carrier in the disengaging state of the sun gear and the carrier.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
As best seen in FIG. 1, 10 is a speed changer case to which a case 11 is 
fixed. An extention housing 12 and case covers 13, 14 are fixedly attached 
to case 11. An input shaft 15 is rotatably supported by a bearing 16 fixed 
to case 11, this input shaft 15 serves also as an output shaft of speed 
changer and integrally connects to a hub 17. Hub 17 is provided with a 
flange portion 18 and a shaft portion 19. A gear 20 is rotatably supported 
by shaft portion 19 of hub 17 through a bearing 21, and is meshed with a 
gear 22 formed on an intermediate shaft 23 which is provided in parallel 
with input shaft 15. Intermediate shaft 23 is rotatably supported by 
bearings 24, 25 fixed to case 11 and is further formed with a gear 26. The 
gear 26 of intermediate shaft 23 is meshed with a gear 27 which is 
coaxially provided with input shaft 15 and is meshed with a gear 28 which 
is provided in parallel with input shaft 15. 
Gear 27 is rotatably supported by a bearing 29 fixed to case 11, and is 
formed on a sun gear 30 of a simple planetary gear 31 within extension 
housing 12. A shaft 32 is rotatably supported by gear 27 through a bearing 
33, and is integrally connected to a carrier 34 of simple planetary gear 
31. A plurality of pinion shafts 35 are fixedly attached to the carrier 
and a pinion 36 meshed with the sun gear 30 and a ring gear 37 is 
rotatably supported by the plurality of pinion shafts 35 through a bearing 
38. 
The ring gear 37 is formed on a first output shaft 39 which is rotatably 
supported by a bearing 40 fixed to the extension housing 12. A bearing 41 
is fixed to an aperture 42 of first output shaft 39 and rotatably supports 
carrier 34. The first output shaft 39 is further provided with a flange 
member 43 for connecting to a propeller shaft (not shown) for a rear wheel 
side. 
Gear 28 is rotatably supported by a bearing 44 fixed to case 11, and a 
second output shaft 45, which is coaxially provided with the gear 28, is 
rotatably supported by a bearing 46. Gear 28 is rotatably supported within 
an aperture 47 of second output shaft 45. Second output shaft 45 is 
provided with a flange member 48 for connecting to a propeller shaft (not 
shown) for a front wheel side. 
In FIGS. 1 to 7 inclusive, an outer spline 49 is formed on an outer 
circumference of flange portion 18 of hub 17, and an outer spline 50 is 
formed on gear 20 and an outer spline 51 is formed on shaft 32; also, an 
outer spline 52 is formed on gear 27. These outer splines 49, 50, 51, 52 
have the same radii. 
A shift fork 53 is engaged with a clutch sleeve 54 connected to the outer 
splines 52, 49 by spline engagement in FIG. 1. Shift fork 53 is fixedly 
attached by a pin 55 to a fork shaft 56 slidably supported by case 11, as 
best seen from FIG. 3. The clutch sleeve 54 is axially moved by operating 
a shift lever (not shown) through fork shaft 56 and shift fork 53. A 
clutch sleeve 57 which is engaged with the outer spline 50 by spline 
engagement is rightwardly depressed toward the clutch sleeve 54 by a 
spring 58 interposed between an aperture 59 provided in the clutch sleeve 
57 and an aperture 60 provided in the gear 20, and is followed to the 
axial movement of clutch sleeve 54. It can be easily understood that the 
engaging portion of shift fork 53 is channel-shaped in cross-section and 
projecting portions are formed on the outer cicumference of clutch sleeves 
54, 57 thereby engaging the engaging portion of shift fork 53 with said 
projecting portions. 
A shift fork 61 is engaged with a clutch sleeve 62 engaged with an outer 
spline 63 formed on the second output shaft 45, and an outer spline 64 
formed on the gear 28 by spline engagement and is fixed to the fork shaft 
56 by pin 65. 
The shift lever (not shown) has three shifting positions, that is, a first 
shifting position, a second shifting position and a third shifting 
position. The clutch sleeves 54, 57 are moved into the state illustrated 
in FIG. 5 in the first shifting position of shift lever (not shown), and 
the clutch sleeve 62 is moved into the state of FIG. 7, the clutch sleeves 
54, 57, 62 are moved into the state of FIG. 1 in the second shifting 
position thereof, and the clutch sleeves 54, 57 are moved into the state 
of FIG. 4 and the clutch 62 is moved into the state of FIG. 6 in the third 
shifting position thereof. These three shifting positions are maintained 
by a lock-ball apparatus 66 disposed between fork shaft 56 and case 11. 
Gears 27, 28 have the same number of gear teeth, while the number of gear 
teeth on gear 26 is fewer than that of gear 27, and the number of gear 
teeth of gear 22 is greater than that of gear 20. 
The operation according to the invention will now be described hereinbelow 
in detail. 
When the shift lever (not shown) is shifted to the second shifting position 
so as to run by front and rear wheel drive on a road, clutch sleeve 54 is 
engaged with outer spline 49 of hub 17 and outer spline 52 of shaft 32 by 
spline engagement, and clutch sleeve 62 is engaged with outer spline 63 of 
second output shaft 45 and outer spline 64 of gear 28 by a spline 
engagement thereby engaging second output shaft 45 with gear 28. In this 
state, the power supplied to input shaft 15 is transmitted to carrier 34 
of simple planetary gear 31 via shaft 32, and is distributed by the simple 
planetary gear 31 in two directions of which one is transmitted from ring 
gear 37 to first output shaft 39 and of which the other is transmitted 
from sun gear 30 to second output shaft 45 via gears 27, 26, 28. And at 
this state, the simple planetary gear 31 activates a differential 
operation. As the gears 27, 28 have the same gear numbers, the torque 
distributing ratio to both output shafts 39, 45 is gear number of sun 
gear/gear number of ring gear. Supposing that the gear number of sun gear 
is 35 and the gear number of ring gear is 65, the above ratio becomes 
35/65. 
When the shift lever (not shown) is shifted to the third shifting position 
so as to run on a rough road, the clutch sleeve 54 is engaged with outer 
spline 52 of shaft 32 and outer spline 51 of gear 27 thereby integrating 
the shaft 32 and the gear 27, and clutch sleeve 57 is engaged with outer 
spline 50 of gear 20 and outer spline 49 of hub 17 thereby engaging gear 
20 with input shaft 15, while clutch sleeve 62 retains the engaging state 
of second output shaft 45 and gear 28. In this state, the simple planetary 
gear 31 is in a locking state by integration of shaft 32 and gear 27, and 
the power applied to the input shaft 15 is transmitted to the gear 26 via 
gears 20, 22, intermediate shaft 23 and is further transmitted from gear 
26 to first output shaft 39 via gear 27 and simple planetary gear 31, and 
also from gear 26 to second output shaft 45 via gear 28. At this time, 
there is no differential movement between front and rear propeller shafts 
(not shown), that is, there is a direct driving operation. 
When the shift lever (not shown) is shifted to the first shifting position 
so as to run rear wheel drive on a highway, clutch sleeve 54 is engaged 
with outer spline 50 of gear 20 and outer spline 49 of hub 17, thereby 
engaging shaft 32 and gear 20 with input shaft 15, and clutch sleeve 62 is 
disengaged from gear 28 thereby disengaging second output shaft 45 from 
gear 28. In this state, the power supplied to input shaft 15 is 
distributed to shaft 32 and gear 20. The power supplied to shaft 32 is 
transmitted to carrier 34 of simple planetary gear 31, and the power 
supplied to gear 20 is transmitted to sun gear 30 of simple planetary gear 
31 via gear 22, intermediate shaft 23 and gears 26, 27, and these 
components of power are transmitted from ring gear 37 of simple planetary 
gear 31 to first output shaft 39. Under these conditions, the gear number 
of gear 22 is more than that of gear 20 and the gear number of gear 27 is 
more than that of gear 26, so that the rotational number of sun gear 30 is 
less than that of carrier 34 thereby operating as over-drive by simple 
planetary gear 31. Supposing that the reduction speed ratio from gear 20 
to gear 27 is 1.8, the over-drive ratio becomes about 0.807. 
Obviously, many modifications and variations of the present invention are 
possible in the light of the above teachings. It is to be understood 
therefore, that within the scope of the appended claims, the present 
invention may be practiced otherwise than as specifically described 
herein.