CA1044114A - Torque converter with variable stator trailing edge - Google Patents

Abstract

IMPROVED TORQUE CONVERTER WITH VARIABLE STATOR

A B S T R A C T

A torque converter has an auxiliary stator intermediate the main stator and the pump. The auxiliary stator has a plurality of holes therethrough adjacent the periphery thereof.
A plurality of vanes are attached to a plurality of rotable shafts extending through said holes for adjustable directing flow of hydraulic fluid from the main stator through the vanes and to the pump. A handle is attached at a fixed angle to an end of each of the shafts. A sleeve has a plurality of slots and one handle is slidably held in each of the slots. Means is provided for operator ajustment of the position of the sleeve to change the angles of the vanes.

Description

The invention relates to torque converters and more particularly relates to torque converters wherein means are provîded for varying the flow angle of fluid delivered from th-e stator of the torque converter to the pump thereof.
Hydraulic torque converters comprising a stator, a pump and a turbine are, of course, well know. Briefly, and by way of summary, the pump of a torque converter impels hydraulic fluid to the turbine of the torque converter, the pump being generally driven via a mechanical linkage by the flywheel of a motor. The hydraulic fluid impelled by the pump impinges upon the blades of the turbine and causes the turbine to rotate, which rotary motion is translated to the drive shaft of the vehicle. As the hydraulic fluid leaves the ~ ~ -turbine it passes through a stationary member (the stator). -The stator includes blades which direct the hydraulic fluid ba~k to the pump. Stators with variable angling of their `~
blades are known to the prior art. Thus, it is known to change the blade angles of a stator so as to change the fluid momentum into the pump of a torque converter. It is also known, as shown, for example, in United States Patent No.
3,250,08~1 lsshed June 26, 1966, Kugel etal to use a main st~ator with fixed blades in combination with an auxiliary stator with blades whose angle relative to the direction of fluid flow can be changed. ;
As in our copending Canadian Application No. 249,003 filed March 29, 1976, the present invention is concerned with an improvement in a torque converter which includes a main stator, a pump and a turbine, the improvement comprising a 30~ particular auxiliary stator wherein control of the position or ' ~'. "'.

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angle of the blades of the stator is controlled by an operator and wherein the change in torque output of the turbine is gen-erally linearly dependant upon the pressure exerted by the op-erator upon a foot pedal or the like controlling the vane position.
According to the present invention a fluid torque converter which includes a main stator secured to a stationary support mernber, a pump arranged to be driven by an engine and a turbine coupled ko an output drive shaft, additionally comprises an auxiliary stator intermediate the main stator and the pump, .
the auxiliary stator including a carrier having a plurality of holes therethrough adjacent the periphery thereof; a plurality of vanes fixedly mounted on a plurality of shafts rotatably ~ . .
mounted in the holes, the vanes being positioned to direct : .
adjus.tably a flow of hydraulic fluid from the main stator past .
the vanes to the pump; a plurality of handlesg one attached at a fixed angle to an end of each of the shafts remote from the ~ ~
vane thereon; and a sleeve rotatable about its longitudinal : .
central axis and having a plurality of slots at one end, the -number of slots being in one to one relation with the number ~ :
of handles, each of which is held slidably in one of the slots. ~-I'he invention is thus able to provide a design which allows complete vane closing during shifting of an attached ~ :.
change-speed transmission with resultingly less energy dis- :
sipation in a clutch of the transmission and partial vane ~: closing at times other than shifting to permit the vehicle :~
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; engine to be operated at a selected ge~erally constant :~ efficient speed over the entire work cycle through controlling torque to the ground and thus ground speed whereby energy savings result. ;

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Furthermore, such a hydrodynamic torque converter will provide infinitely variable torque output between a "maximum" position corresponding tofull prime mover horsepower and a "closed"
position corresponding to complete meridianal flow shut-off.
Another advantage of the invention is that as in the parent application it provides the ability to change from the maximum to the closed position sufficiently fast so that the torque can be changed from maximum to minimum and from minimum to maximum in less than one second.
The design can be economically manufactured such as by investment casting without maching each blade and/or radially indexing to machine pivot bearing bores.
The invention enables use to be made of a standard pump, turbine and stator wheel, whereby if the variable feature is not needed, the variable blade assembly is merely replaced by a spacer. -Advantageously the invention provides a system wherein the turbine torque varles linearly with applied pedal pressure.
A torque converter in accordance with the above-referenced copending application is shown in ~igure 1 to 8 of the accompanying drawings and a torque converter of the present invention in Figures 9 to 12.
Figure l illustrates in side sectional partial elevation a first embodiment of an improved torque converter in accordance with the parent invention;
~igure 2 is a partial view taken along the plane lndicated by II-II of Figure l;
Figure 3 illustrates an alternative embodiment of the structure shown in Figure 2;
Figure 4 is an end view of an auxiliary stator;

' - 4 -' Figure 5 is a view taken along the plane ~-~ of Figure 4;
Figures 6A and 6B illustrate a vane;
Figures 7A and 7B illustrate a handle as attachable to the vane of Figures 6A and 6B;
Figure 8 illustrates speed ratio vz. torque ratio, in percent, graphically over the entire range of vane positions;
Figure 9 illustrates an embodiment of the present invention in a view similar to ~'igure l;
Figure 10 illustrates a view taken along the line X-X
of Figure 9; and :~
Figures 11 and 12 illustrate a vane as is particularly .:
useful in the embodiment of Figures 9 and 10. ~ :
With reference to the Figures 1-8 of the drawings, Figure ~ :
1 illustrates a torque converter 10 and more particularly a fluid torque:converter which includes a pump 12, a turbine 14 and a stator 16. Rotary motion is imparted to the pump :~
12 by the flywheel 18 which is drivingly attached thereto ~ ;.
by the teeth 20 thereof engaging the tee:th 22 of the casing 24 which is rigidly attached to the pump 12 via a plurality of bolts 26, one of which is shown in Figure 1. The arrows in ~:
Figure l:.illustrate the direction of flow of hydraulic fluid through the torque converter 10 as impelled by the pump 12.
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P Xotational~mounting for the casing 24 is provided by the bearings 28 and 29. Hydraulic fluid is retained by the seal The flywheel 18 is driven by, for example~ a conventional int~ernal combustion engine which isnot illustrated. The pump 12, ln~the usual manner, includes a number of pump vanes so arranged as t~o impart fast flow to hydraulic fluid which enters : 30: it while it is rotating. : -:

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The turbine 14 is conventional and includes a plurality of vanes adapted to transfer the energy of the fluid impelled into the turbine into energy of rotation of the turbine and then to direct the fluid, now moving at a slower velocity, to the stator 16. The turbine 14 is attached to the drive shaft :
32 via a plurality of bolts 34, one of which is shown. in ~:
Figure 1, and which attach the turbine 14 to a rlanged collar 36 which is splined to the drive shaft 32 along the interior 38 of the flanged collar 36.
The stator 16 comprises a main stator 40 with fixed :
vanes for directing fluid flow from the turbine 14 therethrough in combination with an auxiliary stator 42. The bearings 44 and 46 allow the turbine 14 and the drive shaft 32 to rotate ,' "-'~- ' -:
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about and within the stationar~ support member 50. Seal ring ~ 48 serves to retain hydraulic fluid ; The auxiliary stator 42 is f'astened to the main statOr l~o via the locator pins 52 and a plurality of bolts 530 The auxiliary sitator 42 is shown more clei~rly in Figures 4 and 5. It includes a central opening 5~, which as shown in F;gure 3., allows mnunting about the drive sha~t 32 through use of the bores 56 for bolts 53 and the holes 57 for the plns 52 through the plate portion 58 o~ the auxil:Lary stator 42~ At the periphery of the plate portion 58 and set at an obtuse angle~
' A~ to said plate portion 58 is a collar 60 having a plurality o~ -j holes 62 therethroughO The number of holes 62 on the collar 60 : is precisely equal ~o the number of vanes 64 of the auxiliary ~:
stator 420 ~anes 64 direct fluid between pump vanes of the pump 120 Referring to Figures 1, 6A, 6B, 7A and 7Bg there are , lllustrated one o~ a pl~ lity of vanes 64 which are integral :1' with a shaft 66, sald shaft 66 passing in rota~ing relation through one o~ ~he holes 62 and extending therebeyond at an end 68 o~
.20 said sha~t 660 Each o~ said shafts 66 includes a ~lange 69 ;:;~
,l ad~acent the vane 64 thereo~ to position said vane 64 relative to said holes 62. Also illustrated is a handle 70 which includes a lever portion 72 and a collar portion 74 having a bore 76 .
therethrough, said bore 76 being adapted to fit over the shaft 66 ;~
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~25 adjacent the end 68 thereof and being held in place bg a pin 78 which passes through a croæs bore 80 and a vane shaft bore 81~ . :
.l The lever portion 72 leaves the collar portion 74 at the . i :
circumference thereof to provide ian effective lever i~rm length :~
ln a pliane generally pari~lIel to said cross bore 80 and at the obtusie angle~ A, ~rom a plane perpendicular to the axis of said ~: bore 76 so as to depend generally toward the drive shaft 32~
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The direction of rotation of the vane 64 relative to the al;uciliary stator 42 is then determined by the rotation of the handle 70 relative to the auxiliary stator 420 An undercut 83 in the sta~ionary support member 50 provides room Ior a sl ight advance o* the lever portion 72 towards the drive shc~t 32 as said lever portion 72 slides within one of a pluralit~ oe slots 8l~o The atlxiliary stator 42, the vanes 64 and the handles 70 can each be inexpensively made as b~ investment casting or llke techniques.
Control o~ the rota-tion of` the handle 70 is providsd by the sleeve 82 and more particu:Larly by the plurali~y o~ slots 84~, one for each o~ the handles 70, sa~d slots 84 belng equally spaced peripherall~ about the one end 86 o~ the sleeve 820 As will be most apparent from Figure 2, the slots 84 are at an ; i.
angle, Bj to the axis 88 o:~ the sleeve 82 (and of the drive sha~t 32)~ Since the sleeve 82 is prevented from rotating about its axis by a pluralil;y of rollers 90 in a plurality o~ bearings 92, motion o~ the sleeve 82 towards the stator 16 necessarily leads to rotation o~ the lever portion 72 o~ the handle 70 and thereby leads to rotation of thereto attached sha~t 66 and the ;
~20 integral vanes 64 o* the a~uciliary stator 420 The lever portion ~ -72 oE the handle 70 is generally so arranged that the vanes 64 are closed when the sleeve 82 is at its rightward-most position~
Because of the direct action o~ the sleeve 82 upon the handle .;
~, 703 the vanes 64 are very quickly shiItable ~rom a "maximum"
25 position corresponding to ~ull output horsapower to a "closed"
position corresponding to meridianal ~low shut-o~E, Generall~, such shi~ting is accomplishable in less than one second.
-, The sleeve 82 has a washer 94 thereabout intermediate the ends thereof~, The sleeve 82 ends in a piston 96" said ~3 piston 96 having a sleeve 98 extending ~rom the side o~ said ~, pisl;on 96 opposite the sleeve 82 side thereof~, Sleeve 98 `'''' .`, ~ .

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contains a plurality of slots 99 wherein lie rollers 90 which linearly guide sleeves 82 and 98 and piston 96 parallel to the axis 88 of the drive shaft 32. Between the washer 94 and a stationary lip 100, a first plurality of conical compression washer type springs 102 are positioned. Between the washer 94 and the piston 96 a second plurality of conical . compression washer type springs 104 are located. The combination of compression springs 102 and lOLI and washer 94 .. bias the piston 96 against the stationary support 112. Extend-ing from the stationary support member 50 is a stop 108 against which the washer 94 abuts as the piston 96 and sleeves 82 and ; 98 are motivated leftwardly towards the stator 16. Thus, once the washer 94 has traveled up to and against the stop 108, the :.
piston 96 must be pushed against the full strength of the second .
, ~ ., ~ 15 and generally stronger plurality of compression springs 104 -;. rather than against the lesser resultant strength of the first . plurality of compression springs 102 and the second plurality -~:- of compression springs 104. If the first plurality of compres~
sion springs 102 is weaker than the second plurality of ,., - ~ ,.
;` 20 compression springs 104, as in the preferred embodiment of the ~ .
`I invention, it becomes necessary to supply added force to moti- :
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vate the sleeves 82 and 98 and the piston 96 towards the .~ stator 16 when the washer 94 abuts the stop 108. This results in a unique control in the responsiveness of the direction of ,: l ~ 25 :the. vanes 64 to the amount of force being exerted to push the , ~ : : sleeves 82 and 98 and piston 96 towards the stator 16. In ,. " ,,, ~ ~
~ practice, the strength of the first plurality of compression s~ .s .- ~1 springs 102 and the second plurality of compression springs ; : 104 are adjusted so as to provide as linear as possible a change in output torque with the force applied to propel the ~ sleeves 82 and 98 and the piston 96 towards the stator ; .
~ 16. Also in practice, the piston 96 and the associated parts ~ . - .
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~: therewi-th are controlled by pressure on a foot pedal lO9 of a ~ vehicle which controls hydraulic pressure against the piston 96, '~ and the vehicle operator gets a relatively uniform change in torque as he relatively unirormly pushes upon the foot pedal lO9 thereby controlling the position o~ the piston 960 The leftwardly movement of the sleeves 82 and 98 and the piston 96 ultimately abuts the sleeve 82 against piston stop llO and controls the maxlm~n opening o~ the vanes 64 and~ hence, the maximum tor~ue :. .. .
capacity of the torque converter lOo When the control pressure ;~
;lO on piston 96 îs minimum3 as when the f`oot pedal lO9 is not being depressed or during a transmission shift;, the vanes 64 ~ :
are closedO
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The vanes 64 are of suffi~ient size and may be rotated --suf~iciently through action of sleeve 82 upon the handle 70 so as to completely shut off ~low from the stator 40 to the pump 12. This is especially useful since it allows complete .:
I closing of the vanes of the auxillary stator during shi~ting ;~ whereby less energy is dissipated in the transmission clutcho I The capabilit~ of partially closing the vanes 64 at times other l20 than during a shift is also advantageous in that this permits `, the vehicIe engine to be operated at a selected e~ficient speed over the entire work cycle through controlling torque to the ~ .
.~ ground and th~s ground speed by opening and closing the vanes 640 ~: With the engine at a selected ef~icient speed an energy saving ~:
~ 25 results since the engine is not accelerated or decelerated : continuously during an entire work cycleO ~:
~igure 8 illustrates torque ratios, in percentJ
available at dif~erent speed ratios, in percentJ as the vanes 64 vary from fully open to ~ully closed responsive to applied .
- 30 pressure on the foot pedal lO9o ~:
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. In the alternate embodiment of the copending application .
illustrated in Figure 3, the slot 84 is somewhat curved or - arcuate rather than linear, although it still generally forms approximately an angle, B, with the axis 88 of the sleeve 82.
The use Or a curved slot 84, as shown in the embodiment of ~ Figure 3, can advantageously be used to make the change in : torque delivered by the turbine 14 be even more linearly dependent upon the position of the foot pedal 109 whlch controls . :
the position of the piston 96.
Adverting now to Figllre 9, there is illustrated therein . an embodiment of the present invention wherein the sleeve 82 `. instead of being movable linearly is movable rotatably under , the impetus of a lever 114 which passes through an opening 116 in the stationary support member 50. The lever 114, as .
will be seen most clearly from Figure 10, is impelled by a ' , ! ., .
~:~ hydraulically activated cylinder 118. Flow to and from the head .~ , . .
and piston ends of the cylinder 118 is controlled by the foot pedal 109. The hydrau~ic cylinder 118 ge~erally has spring ~:
means 120 therein which generally bias the cylinder 118 to propel the lever 114 into a position whereby a plurality of vanes 64' are closed, thus preventing flow through the torque converter 10. As pressure is applied under the command of the foot pedal 109 to the rod end of the hydraulic cylinder 118 and away from the head end thereof, the lever 114 is moved upwardly against the biasing of the spring means 120 whereby the vanes 64' are controllably opened. The slots 84 of the sleeve 82 in the Embodlments illustrated in Figures 9 and 10, are equally spaced peripherally about the one end 86 of the sleeve 82. ~ :~
~ ~, As will be apparent from Figure 9, the slots 84 in the embodi-ments of Figures 9 and 10, are at a zero angle to the axis 88 ~,:, i ~ :

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of the sleeve 82 (and of the drive shaft 32). As the sleeve 82 is rotated about its axis under the impetus of the movement of the lever 114, the lever portion 72 of the handle 70 is moved in or out of the plane of Figure 9 under the impetus of contact with the slot 84, which slot 84 is, of course, parallel 'co the axis 88. Because of the direct action of the sleeve 82 upon the handle 70, the vanes 64', as in the embodiment described previously, are very quickly shiftable from a "maximum" position corresponding to full output horsepower to a "closed" position corresponding to merdiana] flow shut-off. Generall~, such shifting is accomplishable in less than one second.
; Turning to Figures 11 and 12, there is illustrated therein the vane 64' wherein the geometry thereof has been -changed from that of the vanes 64 in Figures 6A and 6B so as to provide for more linear dependence of the torque output of the turbine 14 upon the pressure exerted by the operator upon the foot pedal 109. The vanes 64' differ from the vanes 64 by having --a shaft 66' thereof adJacent a leading edge 122 thereof. This helps to assure that a linear relationship e~ists between ,~ 20 control pressure as exerted by the pedal 109 and vane position (degree of opening).
While the present invention has been described in ~ -~connection with a specific embodiment thereof, it will be ;~ ~ unders~tood that it is capable of further modificatian, and ~ this application is intended to cover any variations, uses : ` :
or ad~aptations of the invention following the principles of the invention as fall within the scope of the appended claims.
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Claims (7)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A fluid torque converter which indludes a main stator secured to a stationary support member, a pump arranged to be driven by an engine and a turbine coupled to an output drive shaft, the torque converter further comprising an auxiliary stator intermediate the main stator and the pump, the auxiliary stator including a carrier having a plurality of holes therethrough adjacent the periphery thereof; a plurality of vanes fixedly mounted on a plurality of shafts rotatably mounted in the holes, the vanes being positioned to direct adjustably a flow of hydraulic fluid from the main stator past the vanes to the pump; a plurality of handles, one attached at a fixed angle to an end of each of the shafts remote from the vane thereon; and a sleeve being rotatable about its longitudinal central axis and having a plurality of slots at one end, the number of slots being in one to one relation with the number of handles, each of which is held slidably in one of the slots.

2. A torque converter according to claim 1, wherein the auxiliary stator carrier includes a plate portion with a collar attached peripherally at an obtuse angle 'A' thereto, and wherein the holes are formed through the collar and are generally equally spaced about the periphery thereof.

3. A torque converter according to claim 1 or claim 2 wherein the handles extend from the ends of the shafts remote from the vanes generally towards the drive shaft.

4. A torque converter according to claim 1, including means for operator adjustment of the position of the sleeve comprising a lever extending substantially radially outwardly from the sleeve and means for adjusting the position of the lever to cause rotation of the sleeve.

5. A torque converter according to claim 4, wherein the lever adjustment means comprises a pedal which controls hydraulic pressure to a hydraulic cylinder which acts against the lever at a position remote from the sleeve whereby shifting of the vanes from a completely open position to a completely closed position is quickly accomplishable.

6. A torque converter according to any of claims 1, 2, or 5, wherein the shafts of the vanes are connected to the vanes adjacent a leading edge thereof whereby turbine output torque varies substantially linearly with applied pedal pressure.

7. A torque converter according to claim 2, wherein the handles each comprise a collar portion having an axis and a lever portion, the collar portions each being attached about an end of each of the shafts remote from the respective vane, the lever portion extending away from the collar portion at the same obtuse angle 'A' from a plane generally perpendicular to the axis of the bore of the collar portion.