Torque converter device with lubricating washer on turbine hub

Discloses a torque converter device with a light stator and turbine. The torque converter device comprises a converter cover, a turbine hub, a washer provided between the cover and the hub, and an oil flow passage provided between the washer and the turbine hub to lighten the stator.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to light weight torque converter devices, and in 
particular to a hydraulic fluid torque converter with a light weight 
stator and turbine. 
2. Description of the Prior Art 
The usual hydraulic torque converter used as a power input device of an 
automatic transmission for vehicles, includes a turbine hub member 
extending in the axial direction, the outer circumference of the turbine 
hub provided as the guide surface for sliding in the axial direction of 
the lock up clutch piston and as the supporting surface for the torque 
converter for supporting the thrust load received at the front side by the 
turbine runner. 
The automatic transmission for a vehicle should be compact, light, and of 
high density because it is desirable to provide a multi-speed automatic 
transmission which simplifies installation in a vehicle, a decrease of a 
fuel consumption, and drivability. Therefore, the usual torque converter 
used as the power input for an automatic transmission should also improve 
the same things. 
The usual torque converter, however, is difficult to lighten because of the 
axial length of the steel turbine hub. 
For attaining the above objective it is proposed that the one-way clutch be 
shorter in axial length and lighter and that the turbine hub be shorter in 
axial length and lighter. However, this causes the turbine hub to be 
unsupported through the thrust bearing by the torque converter because 
such shortening creates a space between the torque converter and the 
turbine hub. The object of the present invention is to provide a light 
torque converter which has a converter cover, a turbine hub, a non-steel 
light washer provided between the cover and the turbine hub for supporting 
the turbine hub in the axial direction, allowing the turbine hub to be 
shortened in axial length. To accomplish the above, the torque converter 
device of the present invention has a converter cover, a turbine hub, a 
washer provided between the converter cover and the turbine hub, and oil 
flow passages extending axially and radially between the inner 
circumference of the washer and the contacting portion of the turbine hub. 
Accordingly, a non-steel washer functions as a spacer between the thrust 
bearing and the turbine hub. The oil flow passages extending in the axial 
and radial directions include a flow passage through the washer to lead 
the oil supplied from the shaft center portion to the outer circumference 
of the torque converter for disengaging the lock up clutch and for 
supplying the oil to the surface between the washer and the turbine hub 
and forming an oil film for preventing the washer from wearing. 
Therefore, according to the present invention, since it is possible to 
provide a non-steel washer which is lighter than the turbine hub and can 
be installed in the space formed by shortening the turbine hub, the 
shorter turbine hub can be connected to the torque converter in the axial 
direction without a weight increase, to provide a lighter weight torque 
converter. These and other objects and advantages of the present invention 
will become clear from the following description with reference to the 
accompanying drawings, wherein:

DESCRIPTION OF PREFERRED EMBODIMENT 
An embodiment of the present invention will now be described with reference 
to the drawings. 
This torque converter, as in the prior art, includes a converter cover 3 
connected to an engine crank shaft 101 by engaging a boss 1 axially to the 
shaft and connecting a drive plate 102 to the boss via a spacer 2, a pump 
impeller 4 connected to the torque converter cover by welding, a turbine 
hub 8 slidably supporting a lock-up clutch piston 7 connected to a 
torsional damper 6 and a turbine runner 5 by rivets. The turbine hub 8 is 
spline engaged to an input shaft 103 of a transmission 100. A stator 9 is 
disposed between the pump impeller 4 and the turbine runner 5, and a 
one-way clutch 10 rotatably supporting the stator is mounted on a fixed 
hollow shaft 104 of the transmission 100. 
In FIG. 1, 61 is a first damper, 62 is a second damper, 63 is a drive 
plate, 64 is a rivet, 65 is a driven plate, 71 is a frictional member, 83 
is an orifice, 90 is a plug, 91 is a snap ring, 92 is a bearing, 93 is a 
passage conduit, 94 is an end bearing, 95 is an outer race, 96 is a 
passage, 97 is an inner race, 98 is a bearing, 99 is a race, 105 is a lip 
type seal and 106 is a bushing. 
In a torque converter of this type the one-way clutch 10 is shorter in 
axial length with an increased number of sprags 90 for maintaining the 
durability of the sprags without increasing the axial length of the 
sprags. The front portion of the turbine hub 8 is made lighter by removing 
its body portion except for the outer cylinder 82 slidably supporting the 
lock up clutch piston 7 and the inner cylinder 81 engaged with the spline 
66 of the input shaft 103. Accordingly, a space is formed between the rear 
surface of the converter cover 3 and the removed portion of the turbine 
hub 8. A washer of resin or light alloy such as aluminum is provided 
between this converter cover 3 and the spaced turbine hub via a thrust 
bearing 11. 
FIG. 2 is a three dimensional view of a non-steel light washer 12. The 
washer 12, as shown in FIG. 2, has an inner diameter which corresponds to 
the outer diameter of the inner cylinder 81 of the turbine hub to engage 
together and an outer diameter such that a sufficient gap is formed 
between the inner circumference of the outer cylinder 82 of the turbine 
hub and the outer circumference of the washer. The washer 12 has one flat 
surface supporting the rear race of the thrust bearing 11 and contacting 
it at the front side thereof (behind the figure) and the other flat 
surface contacting the front surface of the turbine hub at the rear side 
thereof (front side of the figure). The four flow passages 12c and 12d are 
continuously formed, in the embodiment, to extend from the inner 
circumferential portion 12a of the washer 12 to the contact portion 12b of 
the turbine hub 8 in axial and radial directions. The circumference 
passage 12e, extending from the inner circumference side to the rear 
surface side, breaks up the oil fluid lead from the oil conduit 12c in 
axial direction, leaking in the circumferential direction. 
Referring to the FIG. 1, in such a torque converter as this, the oil 
supplied from the shaft 103 via the oil passage of the input shaft 103 is 
supplied to the outer circumference by flowing to the thrust bearing 11 
during lock-up clutch disengagement. Simultaneously, oil is supplied to 
the circumferential conduit 12e through the oil flow passage 12c of the 
washer 12 in the axial direction, supplied to the gap between the outer 
circumference of the washer 12 and the inner circumference of the outer 
cylinder 82 in the turbine hub oil is also supplied to the outer 
circumference side between the converter cover 3 and the clutch piston 7 
provided by oil passing through the thrust bearing for disengaging the 
clutch piston. It is unnecessary here to describe the oil fluid control 
because it is conventional. Since the space formed between the outer 
circumference of the washer 12 and the inner circumference of the outer 
cylinder 82 in the turbine hub is ring-shaped space with a certain axial 
dimension, the oil flow in this space is restricted during pumping oil 
near the washer to maintain pressure in the circumferential conduit 12e of 
the washer 12 to supply sufficient oil to form an oil skin on the 
contacting portion between the washer 12 and the turbine hub 8. Therefore, 
the wear from the sliding contact during lock-up clutch disengagement is 
prevented by forming an oil skin on the surfaces in sliding contact. 
On the other hand, no oil flow is required during lock-up clutch engagement 
because there is no relative rotation between the contacting portions. 
Therefore, it is possible to provide oil flow to it by supplying the oil 
from the orifice 8 disposed in the turbine hub. 
Accordingly, in this embodiment, it is possible to provide a structure in 
which a non-steel washer, which is lighter than the turbine hub, is 
mounted in the space formed by shortening the turbine hub. Now the 
shortened turbine hub can be supported in the axial direction by the 
torque converter without a weight increase, providing a lighter torque 
converter. Compared with the usual oil supply method wherein the thrust 
bearing is lubricated by forming a passage in the thrust bearing race for 
providing the lock-up clutch disengagement pressure, the present invention 
provides for flexible passage design because the oil passage may be 
connected to the washer 12 instead of the above. 
Furthermore, since the cross-section of the washer 12 is a distinctive 
shape, assembly errors such as reverse assembly can be prevented. Since 
the washer 12 has a circumferential conduit 12e at its inner circumference 
side, the temperature in the converter compartment is prevented from 
increasing by using the conduit as a passage for supplying the oil from 
the converter compartment to the control compartment. In this case, the 
orifice 83 has only to be provided on the inner circumference of the 
turbine hub. It is possible to make a circuit for providing oil during 
lock-up clutch engagement without decreasing the lock-up clutch torque 
capacity in accordance with the oil supply from the converter compartment 
to the control compartment via an orifice, same as in the case of 
connecting the converter compartment directly to the control compartment 
and providing the orifice in the lock-up piston 7 for attaining the above 
described object. 
Though only one embodiment of the present invention has been explained, it 
goes without saying that various other embodiments, which include 
different components from those of the above embodiment, can be provided 
within the scope of the claims.