Variable speed transmission device

A variable speed transmission device including a torque variator of the type in which a first rotatable element is in rolling friction engagement with a second nutatable element having an axis movable in a biconical path about the axis of the first element. The first element supports a pair of axially movable cone-like members fixed for rotation with the first element and each having exterior surfaces of revolution defined by a curved generatrix to be convex in axial section and converging away from a point of first and second element axes intersection. The rolling friction surfaces of the second element are defined by interior cylindrical surfaces on a tube-like member and means are provided for adjusting the angle of the second element axis with respect to the first to vary the radii at the point of frictional contact on the cone-like members. A third element rotatable on the first axis extends through the tube-like second member and is cut away to enable the frictional engagement of surfaces on the cone-like members with the internal surfaces of the second element. The third element carries adjustably eccentric journals having fluid control means operable in diammetrically opposite directions to vary the angle at which the axis of the second element intersects the axis of the first element. Input torque is preferably provided by a clutch to the third element whereas the variable speed output of the variator is transmitted through a multi-speed shiftable gear train.

CROSS-REFERENCE TO RELATED APPLICATION 
This application is related to U.S. Patent Application Ser. No. 738,472, 
filed Nov. 3, 1976 by the joint inventors named herein and commonly 
assigned with the present invention. 
BACKGROUND OF THE INVENTION 
This invention relates to improvements in variable speed transmission 
devices and more particularly, it concerns an improved transmission of the 
type in which torque is transmitted by rolling frictional engagement at 
two points of contact between a pair of first and second elements having 
surfaces of revolution angularly disposed on intersecting first and second 
axes, the first element being rotatable on the first axis whereas the 
second element nutates so that the second axis revolves in a biconical 
path about the first axis. 
In a co-pending application for U.S. Patent, Ser. No. 706,291, filed July 
19, 1976 by Yves Jean Kemper, there are disclosed several embodiments of a 
transmission or torque variator in which a gyroscopic couple is deployed 
at two points of rolling friction contact between a first element 
rotatable on its own axis and a second element having an axis revolvable 
about the first axis in a biconical path such that the second element 
undergoes nutational movement with respect to the first. In certain 
embodiments, the gyroscopic couple is depolyed to develop the normal force 
necessary to retain the rolling surfaces of the respective first and 
second elements in frictional engagement with each other whereas in other 
embodiments, the normal force required for frictional engagement is 
developed by mechanical means opposed by inertial forces including the 
gyroscopic couple to minimize the load-supporting requirements of bearings 
used in the transmission. While both forms of the transmission, as thus 
characterized, have demonstrated great potential from the standpoint of 
providing an exceedingly well-balanced, variable speed torque transmission 
requiring a small number of easily machined components, the latter form in 
which the inertial forces oppose a mechanically induced normal friction 
force couple has shown particular promise because of the facility it 
provides for reducing both size and friction losses in bearings used to 
support the respective first and second elements. 
Variation in angular velocity between an input shaft and an output shaft of 
such a transmission is effected by providing the rolling friction surfaces 
coupled to one of the shafts on a pair of generally conical members each 
having an apex half-angle approximately the same as the angle between the 
intersecting axes of the first and second elements. The conical surfaces 
converge from the point of first and second element axes intersection and 
are movable in the direction of convergence into engagement with annular 
rings carried by the second elements. The rings also are axially 
adjustable on the second element so as to engage the conical members at 
varying radial distances from the axis of the conical members. Inasmuch as 
the annular rings are of a fixed radius, the speed ratio of input and 
output shafts connected to the respective first and second elements will 
vary with the radius of the conical members at the point of rolling 
friction engagement. 
Although various control devices are disclosed in the aforementioned 
co-pending application for controlling the axial positioning of the 
annular rings carried by one or the other of the first and second 
elements, the annular rings as well as the control mechanism for their 
axial adjustment represent a relatively complicated control organization 
in the overall basically simple transmission. Accordingly, there is room 
for improvement principally in the control mechanism necessary to the 
attainment of the variable transmission speed ratios. 
SUMMARY OF THE PRESENT INVENTION 
In accordance with the present invention, a transmission is provided in 
which frame supported drive input and output members are interconnected by 
a torque variator including a first element having a first axis fixed 
relative to the supporting frame, a second element having a second axis 
intersecting the first axis at a point of axes intersection, and a third 
element rotatable on the first axis and rotatably engaged with the second 
element to develop a biconical movement or nutation of the second element 
about the point of axes intersection and circumferentially of the first 
axis. The first element has a pair of rolling surfaces disposed about the 
first axis, one to each side of the point of axes intersection. The second 
element also is formed having rolling traction surfaces to engage those on 
the first at two points of rolling frictional engagement. A hydraulic 
control system is provided for adjusting the angle of intersection between 
the first and second axes to shift the two points of rolling frictional 
engagement in opposite axial directions. 
The rolling surfaces on one of the elements are established by an interior 
cylindrical surface positioned about a pair of cone-like members supported 
for rotation as the other of the elements and for axial movement toward 
and away from the point of axes intersection, each of the cone-like 
members having exterior surfaces of revolution converging from the point 
of axes intersection and defined by curved, preferably circular 
generatrices. To enable both of the elements to be supported by simple 
radial bearings such that both elements are directly or positively 
supported on their respective axes in relation to the transmission frame, 
the radii of generatrix curvature is long and related geometrically to 
variations in the surface radius defined by the generatrix and to 
variations in the angle of axes intersection. 
The third element extends within and through the rolling traction surfaces 
of the second element, is cut away to enable frictional contact of the 
rolling surfaces on the first element with those of the second, and 
carries at opposite ends cooperating adjustable bearing assemblies 
operated by hydraulic piston/cylinder units to vary the angle of axes 
intersection between the first and second elements. The nutating second 
element is grounded to the frame in a manner to prevent rotation thereof 
on the second axis by an unique double U-joint system positioned centrally 
and thus symmetrically with respect to the second axis. A fluid control 
system capable of operating the piston/cylinder units to adjust the 
respective angular positions of the second element is effectively provided 
by an externally controlled pump system carried by the third element of 
the transmission. 
For a given input speed, the rotational speed of the transmission output, 
preferably an output shaft, may be varied continuously through the range 
of radii defined by the rolling surfaces on the cone-like members. 
Additionally, a gear-type transmission is connected to the cone-like 
members to provide multiple increments of such continuously variable speed 
ranges as well as a neutral to reverse the direction of output shaft 
rotation. Also, the transmission may be releasably coupled to a source of 
input torque by a clutch. 
Among the objects of the present invention are therefore: the provision of 
an improved variable speed torque transmission; the provision of such a 
transmission in which a variation in transmission speed ratio is effected 
by variation in the angle of axes intersection between a rotatable element 
and a nutating element in frictional engagement with each other at two 
points of contact spaced equally from the point of axes intersection; the 
provision of such a transmission having an improved torque variator; the 
provision of such a torque variator in which all components are positively 
supported and controlled without need for complex supporting or control 
components; the provision of an improved double U-joint system for 
grounding the nutating element of such a torque variator with the frame 
thereof; the provision of a unique control organization for such a double 
U-joint system; the provision of a unique bearing support for the second 
element of such transmissions; the provision of such a transmission which 
may be easily coupled to a source of input torque by a releasable clutch; 
and the provision of such a transmission having an incremental output 
speed variation superimposed on the continuous speed ratio variation 
effected by the torque variator thereof. 
Other objects and further scope of applicability of the present invention 
will become apparent from the detailed description to follow taken in 
conjunction with the accompanying drawings in which like reference 
numerals designate like parts.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
A preferred embodiment of the overall transmission in accordance with the 
present invention is shown in FIG. 1 of the drawings to include an 
enclosed frame or housing 10 having at one end a peripheral mounting 
flange 12 adapted to be secured directly to the frame or block of an 
engine or other suitable source of driving torque represented by the 
phantom line illustration to the left of FIG. 1. At its opposite end, the 
frame 10 is provided with an inwardly directed flange 14 delineating one 
end of a gear box generally designated by the reference numeral 16. An 
intermediate, inwardly directed flange 18 on the housing 10 separates the 
opposite end of the gear box 16 from a torque variator 20. As will be 
described in more detail below, the torque variator is connected in part 
to the frame 10 by way of a further inwardly directed flange 22. 
Torque input to the transmission is preferably through a centrifugal clutch 
generally designated by the reference numeral 24 and located adjacent the 
peripheral mounting boss 12 on the frame. The clutch 24 is, in itself, 
conventional and as such includes a drive plate 26 having a central recess 
28 through which torque transmitting pins 30 project for engagement with 
and support by an input shaft (not shown) appropriately journalled in the 
power source to which the transmission is connected in practice. The drive 
plate 26 carries a fixed annular friction pad 32 on one side of a driven 
disc 34. The disc 34 is adapted to be seized between the fixed friction 
pad 32 and an annular clamping pad 36 by an annular piston 38 movable by 
hydraulic fluid or oil supplied from an annular chamber 40, outwardly 
through a port 42 and under the control of a sensor 44. Thus, with no 
rotation of the drive plate 26, oil is fed past the sensor 44 and the disc 
34 of the clutch is in a disengaged condition. As the drive plate 26 
undergoes rotation, the oil in the port 42 will be moved outwardly by 
centrifugal force, fed against the annular piston 38 until the output disc 
34 is engaged by the friction pads 32 and 36. 
Extending longitudinally of the transmission on a first or primary 
transmission axis 46 are a pair of concentric torque transmitting shafts 
48 and 50. The central shaft 50 is keyed directly to the clutch drive 
plate 26 and may be coupled at its end opposite from the clutch to 
auxiliary engine components (not shown) or other means to be connected in 
a direct drive relationship with the input torque to the transmission by 
way of the drive plate 26. The hollow shaft 48 is rotatable independently 
of the central shaft 50 and supported in the frame 10 on the axis 46 by 
bearings 52, 54 and 56. As will be seen from the description to follow 
below, the hollow shaft 48 in the disclosed embodiment is the output of 
the torque variator 20 and the input to the gear box 16. Torque output 
from the overall transmission is by way of a countershaft 58 coupled to 
the hollow shaft 48 through the gear box 16. 
As shown in FIG. 1, the gear box 16 includes a pair of pinion gears 59 and 
60 keyed for rotation with the hollow shaft 48 and in engagement at all 
times with pinion gears 62 and 64 which are freely rotatable on the output 
counter shaft 58. It will be noted that although the teeth of the 
respective gear sets 59, 62 and 60, 64 are shown out of engagement, these 
gears are engaged by reversing idler pinions (not shown) so that both 
gears of each set rotate in the same direction. A coupling gear 66 is 
splined for rotation with the counter shaft 58 and is slidable axially 
thereon. The gears 62, 66 and 64 are provided with interengaging axial 
sets of teeth 68 and 70 so that the gear 66 may be maintained in an 
intermediate position as shown in FIG. 1 or in positions of coupled 
engagement with either of the gears 62 and 64. Since the gears 62 and 64 
will be driven by the gears 59 and 60 in the same direction as the hollow 
shaft 48, a first forward gear ratio may be effected by engagement of the 
coupling gear 66 with the gear 62. In this gear ratio, torque transmission 
from the shaft 48 will be from the gear 59 through an idler gear (not 
shown) to the gear 62 and the coupling gear 66 to the output counter shaft 
58. A second forward gear ratio involves merely shifting the coupling gear 
66 into engagement with the gear 64 so that the train will be through the 
gear 60 and another idler gear (not shown) to the gear 64, through the 
coupling gear 66 to the shaft 58. A reversal of the counter shaft 58 with 
respect to the hollow shaft 48 is effected by the intermediate position 
shown. In this condition, the coupling gear 66 is driven directly by a 
gear 72, normally rotatable freely on the shaft 48, but driven by 
engagement by axial teeth 74 with the gear 59. 
In accordance with the invention, input torque operable to drive the clutch 
24 at an angular velocity .alpha. is transmitted to the gear box 16 by 
rotation of the hollow shaft 48 at an angular velocity .omega. as a result 
of the operation of the torque variator 20 through an infinite variation 
of speed ratios .omega./.alpha.. Although the several structural 
components of the torque variator which contribute to this operation will 
be described in detail below, an understanding of this basic operation may 
be gained by noting that the torque variator 20 is comprised of three 
assemblies which are movable as units or elements; namely, a first 
rotational element 78 concentric with the first axis 46, a second 
nutatable element 80 symmetrically disposed about a second axis 82 
inclined with respect to the first axis 46 by an angle a and intersecting 
the first axis at a point of axes intersection S, and a third element 84 
concentric with and rotatable on the first axis 46. The third element 84 
functions in the manner of a support by which the angular disposition of 
the second axis 82 relative to the first axis 46 is maintained. 
As may be observed in FIG. 1, the first element 78 of the torque variator 
20 is established by a pair of cone-like members 86 and 88, splined for 
direct rotation with the hollow shaft 48 and slidable axially thereon in 
symmetry toward and away from the point S. The members 86 and 88 are 
biased away from each other in the disclosed embodiment by compression 
springs 90 though other suitable means such as a hydraulic system or a 
system of opposed helical splines may be employed to this end. Each of the 
cone-like members 86 and 88 is identically shaped to define an outer 
rolling traction surface 92 having a variable radius R.sub.w with respect 
to the first axis 46. Also, it will be noted that the generatrix of each 
of the surfaces 92 is a curve having a long radius R.sub.c which is 
related to minimum (.dwnarw.) and maximum (.uparw.) values the radius 
R.sub.w and the angle a under the equation: 
##STR1## 
The second or nutating element 80 of the torque variator is essentially a 
tube-like structure having concentric journal and rolling or traction 
surfaces of revolution about the second axis 82, such surfaces being 
designated respectively by the reference numerals 94 and 95 in FIG. 1. 
These surfaces are duplicated on opposite sides of the point of axes 
intersection S. Also it is to be noted that the rolling or traction 
surfaces of revolution 95 are of the same radius R.sub.b with respect to 
the axis 82 and that the surfaces 95 engage the surfaces 92 on the 
cone-like members 86 and 88 at two points of contact P1 and P2 spaced 
equally and oppositely from the point S. 
The journal surfaces 94 on the second element 80 are rotatably engaged by 
bearing assemblies 96 and 98 carried as a unit with the third or support 
element 84 in a manner which will be described below. Also, a system of 
U-joints generally designated by the reference numeral 100, extend from 
the flange 22 on the frame 10 to the second element 80 to restrain the 
latter against rotation on the second axis 82 without in any way 
inhibiting nutation of the member 80 in a manner such that the second axis 
82 may travel in a biconical orbit or path about the first axis 46 in 
symmetry with the point of axes intersection S. 
In the disclosed embodiment, the third element 84 serves to drive the 
torque variator 20 and as such is coupled for rotation with the output 
disc 34 of the clutch 24 by exterior splines 102. Also, it will seen in 
FIG. 1 that the element 84 is supported for rotation at the one end 
thereof in the vicinity of the splines 102 independently of the shaft 48 
by the previously mentioned bearing 56 and also independently of the drive 
plate 26 of the clutch by bearing 104. At its opposite end, the member 84 
is journalled for rotation on the shaft 48 by a bearing 106. Also, a 
central bearing sleeve 108 is provided between the shaft 48 and a 
connecting ring or collar 110 forming a part of the element 84. An 
understanding of the manner in which torque is transmitted from the third 
element 84 to the nutating second element 80 may be gained by reference to 
FIGS. 2-6 of the drawings in which the structure of the element 84 is 
fully illustrated. 
As shown in FIG. 2, the element 84 is constituted by a pair of generally 
similar longitudinal half-sections 112 and 114 secured in an end-for-end 
relationship against opposite faces of the connecting ring or collar 110 
by a series of axial screw bolts 116 or other equivalent means. Each of 
the sections extends from the collar 110 as a sleeve-like structure to 
journal bosses 118. An intermediate portion of each section 112 and 114 is 
cut away to provide diammetrically opposite openings 120 and 122 in the 
assembled element. It will be appreciated that the openings 120 and 122 
expose the cone-like members 86 and 88 so that the rolling 
tractionsurfaces 92 thereon are presented through the member 84. 
Each of the journal bosses 118 is similarly shaped to define an integral 
yoke portion 124 shown most clearly in FIGS. 5 and 6 to include a pair of 
outwardly spaced longitudinally extending leg plates 126 each having an 
inclined bolting surface 128. A cylinder head bracket 130 is secured by 
bolts 132 to both leg plates 126 of each yoke 124. Each of the brackets 
130 defines an inwardly facing cylinder 134 to which oil or other suitable 
hydraulic fluid may be fed by a passageway 136 formed in the bracket 130 
and communicating with passageways 138 and 140 in each yoke 124 (FIG. 3). 
In the embodiment of FIGS. 1-6, the bearing assemblies 96 and 98 each 
include a series of rollers to engage the journal surfaces 94 on the 
nutatable second element 80 and which are supported by an outer race 
member 142. The outer race member 142 is formed with a piston 144 adapted 
to be received in the cylinder 134 and is further provided with external 
flats 146 slidable on the inner surfaces of the leg plates 126 of each 
yoke 124. It will be noted that the pistons 144 of the outer races 142 in 
the respective bearing assemblies 96 and 98 at opposite ends of the member 
84 are diammetrically opposed. In light of this arrangement, the pistons 
144 and cylinders 130 function as diametrically opposed extensible means 
by which the tube-like nutating member 80 may be adjustably tilted about 
the point of axes intersection S by simultaneous introduction of oil to or 
discharge of oil from the cylinders 134 of each of the bearing assemblies 
96 and 98. Such a tilting adjustment will, of course, result in an 
adjustment of the second axis 82 to vary the angle a between minimum 
(a.dwnarw.) and maximum (a.uparw.) values. The effect of such a variation 
in the angle a results in simultaneous shifting of the contact points P1 
and P2 toward or away from the point of axes intersection S. As a result 
of this movement of the contact points, the radius R.sub. w of the 
surfaces 92 on the cone-like members 86 and 88 will vary from a minimum 
value for a.uparw. to a maximum value for a.dwnarw.. Since the radius 
R.sub.b of the rolling traction surfaces 95 on the nutating member 80 
remains constant, the ratio R.sub.b /R.sub.w or .rho. will vary directly 
with the angle a. 
The operation of the torque variator 20 to transmit torque rotatably 
driving the third element 84 at a velocity .alpha., to output torque at 
infinitely varying speed ratios in the hollow shaft 48 at velocities 
.omega. may now be appreciated. In particular, rotation of the member 84 
and correspondingly, coordinated orbital movement of the outer races 142 
of the two bearing assemblies 96 and 98, will cause the member 80 to move 
in a nutational manner so that the axis 82 thereof is carried in a 
biconical path about the first axis 46 with the surfaces 95 and 92 in 
friction transmitting engagement with each other at the two points P1 and 
P2. Since the member 80 is prevented from rotation on the axis 82 by the 
U-joint system 100, the cone-like members 86 and 88 as well as the shaft 
48 to which they are splined will be driven at the velocity .omega. in 
accordance with the equation .omega. = .alpha.(1 - .rho.). Since the 
radius R.sub.b is always greater than the radius R.sub.w, the function 
.rho. will always be in excess of 1. As a result, .omega. is a directional 
reversal of .alpha.. 
With reference again to FIGS. 2-6 of the drawings, it will be noted that 
the bolting surfaces 128 on the leg plates 126 of each of the yokes 124 is 
inclined so that the axis of each cylinder 134 is at an angle with respect 
to the axis 46 of the element 84. This angle is selected to be 
approximately one-half the value of variation in the angle a or midway 
between a.uparw. and a.dwnarw.. Also, the pistons 144 are constructed to 
facilitate a degree of axial misalignment with the axis of the cylinders 
134 to accomodate variations in the angle a. 
In FIGS. 7 and 8 of the drawings, an alternative form of the bearing 
assemblies 96 and 98 is shown with parts corresponding to those of the 
assemblies 96 and 98 being designated by like reference numerals but 
primed. Hence, in the alternative embodiment of FIGS. 7 and 8, the piston 
144' is provided on a bearing body 142' having external flats 146' for 
sliding movement with respect to the yoke 124 in the same manner as the 
outer race 142 of the bearing assemblies 96 and 98 previously described. 
In this instance, however, the inner surface of the body 142' is provided 
with a semi-cylindrical bearing surface 148 engagable directly with the 
journal surfaces 94 on the tube-like nutating member 80. The surface 148 
is provided with oil slots 150 to provide a hydrostatic bearing between 
the body 142' and the journal surfaces 94 on the nutating member. The 
piston 144' is modified to include a sliding seal nipple 152 receivable in 
a central chamber 154 to which oil is supplied in the same manner as it is 
to the cylinder 134' for actuating the piston 144'. The oil slots 150 are 
in communication with the nipple 152 by ports 156. 
Although the alternative embodiment of the bearings illustrated in FIGS. 7 
and 8 functions in all respects like the bearing assemblies 96 and 98 in 
the embodiment of FIGS. 1-6, the alternative embodiment provides improved 
operation in at least some applications of the overall transmission by 
reducing friction between the bearings and the tube-like nutating member 
80. In particular, and assuming friction losses of a hydrostatic bearing 
to be comparable with that of a roller bearing, friction is reduced as a 
result of minimizing the surface contact in the bearing. 
In FIGS. 9-11 of the drawings, the U-joint system 100 by which the nutating 
member 80 is interconnected with the frame 10 to prevent rotation of the 
member 80 about the axis 82 is more clearly shown to include an exterior 
mounting flange or ring 158 having a plurality of bolt holes 160 for 
securement to the inwardly directed flange 22 of the frame 10 as shown in 
FIG. 1 of the drawings. In FIG. 9, a pair of mutually perpendicular 
transverse pivot axes X--X and Y--Y are shown and lie in a plane 161 
intersecting the point of axes intersection S. The system disclosed may be 
characterized as a double U-joint and as such includes a first outer ring 
162 pivoted on the axis Y--Y by trunnion journals 163 in the mounting ring 
158 and a second inner ring 164 pivoted from the outer ring 162 on the 
axis X--X by a pair of trunnion sleeves 166. The nutating member 80 is 
pivotally supported from the inner ring 164 on the axis Y--Y by trunnions 
168. 
Although the use of a single U-joint (a system in which only one of the 
rings 162, or 164 is used with trunnion support of the member 80 from a 
single ring on one of the perpendicular transverse axes and the ring 
pivotted from the mounting ring 158 on the other of such axes) would 
effect a universal grounding of the member 80 with the frame, the angular 
disposition of the tube 80 in the context of rotation about the axis 82 
would not be constant as will be appreciated by those familiar with the 
art relating to U-joints. While this condition is corrected by the use of 
a double U-joint, the common pivot point S of both rings 162 and 164 is 
best practiced where the relative movement of both rings 162 and 164 is 
controlled. To this end, a pair of swivel arms 170 are disposed on the 
axis X--X. As shown most clearly in FIG. 10 of the drawings, the arm 170 
is provided with spherical bearing surfaces 172, 174 and 176 intermediate 
its length and at opposite ends respectively. The spherical bearing 174 is 
received in a socket 178 carried by an externally circular sleeve 180 to 
establish one of a pair of end fulcrums for the arms 170. The sleeve 180, 
in turn, is received in an oblong slot 182 in the nutating member 80. The 
sleeve 180 is, therefore, capable of sliding movement in the slot 182 and 
also with a measure of freedom in a plane perpendicular to the axis 82 of 
the member 80 or the plane 161. The intermediate spherical bearing 172 is 
pivoted in a socket 184 carried directly by the trunnion sleeve 166 to 
establish an intermediate fulcrum at which the inner and outer rings 162 
and 164 are pivotally interconnected on the axis X-X. The socket 184 is 
fixed against axial movement in the trunnion sleeve 166. The spherical 
bearing 176 is pivoted in a socket 186 to establish the other of the pair 
of end fulcrums afore-mentioned. The socket 186 is carried by a sleeve 188 
for axial movement relative to the mounting ring 158. 
As a result of this organization of the control arms 170, the member 80 is 
free to undergo nutating movement relative to the frame 10 and maintain a 
truly constant non-rotatable orientation on the axis 82 while the relative 
angular orientation of the rings 162 and 164 is controlled. The U-joint 
system is, therefore, prevented from locking as might occur if both rings 
were completely free to pivot on the respective trunnion axes X--X and 
Y--Y. 
Reference is now made to FIGS. 1-4 and 12-14 of the drawings which 
illustrate a fluid system for both lubricating the transmission and 
controlling the actuation of the pistons 144 to change the angle a at 
which the axes 46 and 82 intersect. As shown in FIG. 1, the inwardly 
directed flange 18 on the frame 10 supports a hub 188 which supports the 
bearing 54 and in addition, defines an annular chamber 190 to which oil is 
fed by a passageway 192 communicating with an external supply of oil 
represented by a hose fitting 194. The chamber 190 communicates through 
the hollow shaft 48 by ports 196 so that oil may pass from the chamber 190 
through the annulus extending along the complete length of the concentric 
shafts 48 and 50. The shaft 48 is further provided with radial ports such 
as a port 198 through which oil passing between the shafts 50 and 48 will 
be thrown outwardly by centrifugal force alone or combined with system 
pressure under which the oil is passed to the annular chamber 190. 
Although various additional lubrication passages are illustrated in FIG. 1 
of the drawings, it is believed that further description of these passages 
is unnecessary to a complete understanding of the present invention. 
The bearing boss 118 on the half-section 112 is provided with an internal 
oil collection groove 200 which serves as a reservoir for the supply of 
oil to an oil pump 202 supported directly by the member 84. Although the 
details of the pump 202 will be described in more detail below with 
reference to FIGS. 12-14, it will be observed in FIGS. 1-4 that a 
passageway 204 extends from the pump 202 and communicates with an annular 
passageway 206 in the connecting ring 110. The annular passageway 206 
further communicates with an axial passageway 208 extending to the bearing 
boss 118 and yoke 124 of the other half-section 114. Communication with 
each of the cylinders 134 at opposite ends of the member 84 is as 
described above with respect to FIGS. 3 and 4 and including the 
passageways 136, 138 and 140. 
As shown most clearly in FIG. 12, the pump 202 is provided with a 
reciprocal pumping plunger 210 operable in a cylindrical bore 212 having 
an inlet check valve 214 and a one-way outlet valve or ball check 216. The 
valve 214 communicates with the annular track 200 by way of a port 218 and 
a slot 220 which serves as a small storage reservoir of oil for the pump. 
The outlet check valve 216 is in communication with the port 204 such that 
upon reciprocation of the plunger 210, oil will be fed under pressure to 
the passageway 204 and ultimately to the piston cylinders 134 in a manner 
to increase the inclination of the nutating member 80 with respect to the 
axis 46 or to increase the angle a. 
A dumping valve arrangement is positioned adjacent the pump and as shown in 
FIG. 12 includes a plunger 222 adapted to moved against a ball check 224 
to open communication of the port 204 with a dump valve 226. Thus, it will 
be appreciated that when the ball check 224 is moved to an unseated 
position, both discharge from the chamber 212 and oil from the passage way 
204 may be passed directly through the dump valve 226. 
The manner in which the pump and dump valve arrangement illustrated in FIG. 
12 are actuated and controlled may be seen by reference to FIGS. 1, 13 and 
14 of the drawings. Both the dump valve rod 222 and the plunger 210 
support rollers in a position to engage an annular track 230 pivotally 
supported from the hub 188 by pintels 232. An arm 234 extends from the 
ring defining the track 230 on the side thereof opposite from the pintels 
232 and is engaged by a control linkage 236 for pivotal movement between 
three positions depicted in FIG. 14 of the drawings. Thus, when the track 
230 is maintained in a plane truly perpendicular to the axis 46, no 
pumping action will occur nor will the dump valve 224 be opened. 
Accordingly, the condition of the pistons 144 will be stable in this 
position of the track 230. Pivotal inclination of the track 230 to the 
position represented by the line A in FIG. 14 will result in reciprocation 
of the plunger to pump oil into the cylinders 134. The dump plunger 222 
will be retracted away from the dump valve 224 in this position of the 
track 230. If the track is pivoted to the position B, however, the plunger 
222 will unseat the dump valve 224 causing fluid to be exhausted from the 
cylinders 134 and correspondingly bring about movement of the pistons in 
the other direction. 
Thus it will be appreciated that as a result of the present invention a 
highly effective torque transmitting system is provided by which the 
aforementioned objectives are completely fulfilled. It will also be 
appreciated by those skilled in the art that various modifications and/or 
changes may be made in the disclosed embodiment without departures from 
the inventive concepts mainfested thereby. Accordingly, it is expressly 
intended that the foregoing description is illustrative of a preferred 
embodiment only, not limiting, and that the true spirit and scope of the 
present invention be determined by reference to the appended claims.