US2952977A

US2952977A - Rotary hydraulic couplings

Info

Publication number: US2952977A
Application number: US628768A
Authority: US
Inventors: Kluge Eneval
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-12-17
Filing date: 1956-12-17
Publication date: 1960-09-20
Anticipated expiration: 1977-09-20

Description

Sept. 20, 1960 E. KLUGE ROTARY HYDRAULIC couRLINGs 4 Sheets-Sheet l Filed Dec. 17, 1956 Sept. 20, 1960 E. KLUGE ROTARY HYDRAULIC COUPLINGS 4 Sheets-Sheet 2 Filed Dec. 17, 1956 Sept- 20, 1960 E. KLUGE 2,952,977

ROTARY HYDRAULIC COUFLINGS Filed Deo. 17, 1956 4 Sheets-Sheet 3 ATTORNEY ROTARY HYDRAULIC COUFLINGS Filed Deo. 17, 1956 4 Sheets-Sheet 4 X09 /07 //7 ZZ/ INVENTOR BY @Mgg/gg ATTORNEY United States, Patent @hice 2,952,977 norARY HYDRAULIC coUPLlNGs Eneval Kluge, 117 9- White Bear Ave., St. Paul, Minn.

Filed Dec. 17, 1956, Ser. No. 628,768

13 Claims. (CIV. 60-54) This invention relates to an improvement in rotary 'hydraulic couplings and deals particularly with a'variable speed coupling which tends to maintain a constant adjusted speed.

An object of the present invention resides in the provision of a rotary hydraulic coupling which includes a drive member to which is secured a rotatable hub. A series of vanes are pivotally supported intermediatetheir ends to this hub. These vanes are so constructed and arranged that in completely retracted position they provide a cylindrical surface. In their other extreme position, the vanes extend outwardly in a generally radial direction from the center of the hub. l The hub and its vanes are rotatably supported in a chamber having internally extending tins. This casing or housing is rotatably supported and is connected to the driven member. When the chamber is filled with hydraulic fluid and the vanes are fully retracted, they pro vide a cylindrical structure which may rotate within the fluid with little tendency to rotate the housing. As the vanes are pivoted to swing outwardly from the hub, they provide an everkincreasing force tending to move the housing with the hub.

A feature of the present invention resides in the provision of a coupling of the type described Vincluding vanes which are pivotally supported on axes which are generally parallel to the axis of rotation of the supporting hub.

The inner end of each vane is heavily weighted. Thus, during the rotation of the hub, centrifugal force tends to swing the vanes toward closed or retracted position. In the event the force against the vanes increases, the centrifugal force acting upon the weighted ends of the vanes is overbalanced, tending to cause the vanes to -project a greater distance from the hub.

A further feature of the present invention resides in the provision of a rotary coupling' of the type described, including a manually operable means for adjusting the position of the vanes Within the housing. This manually operable means includes a lost motion mechanism which permits some adjustment of the vanes independently o'f the manually operable control mechanism. As a result, if the load of the driven member increases, and the speed of rotation of the drive member is decreased to an extent where the centrifugal force upon the vanes decreases to a predetermined extent, the vanes may automatically project outwardly to a greater extent, thus providing a greater tendency to rotate the housing in unison with the hub. In a similar manner if the speed of rotation tends to increase, it also increases the force tending to retract the vanes.

A feature of the present invention resides in the provision of a hydraulic coupling which includes a series of pivotally supported vanes mounted upon a hub and in which the vanes are so shaped to provide a seal between the inner portion of the hub and the vanes at all times. The surface of the vanes is at all times in substantial surface contact with the hub regardless of the .pivotal position thereof.

Patented sepewao, 19,60;

A further feature of the present invention resides in the provision of a novel means for projecting and retracting the vanes. An arm is connected to each vane and to an axially slidable support. By moving the axially slidable support in an axial direction, the arms act to swing the free ends of the vanes from one extreme position to the other. Means Vare also provided for compensating for changes in angularity between the points of connection of the arms with the vanes and the slidable support.

These and other objects and novel features of the present invention will be more clearly and fully setforth in the following specification and claims.

In the drawings forming a part of the specification; p p

Figure l is a longitudinal sectional View through the rotary hydraulic coupling and the control therefore.

Figure 2 is taken on the irregular section line 2- -2 of Figure l. Y

Figure 3 is a view similar to Figure 2 on a somewhat reduced scale showing the vanes in a different rotative position. Y

Figure 4 is a diagrammatic View of the hub and, lthe vanes, the view showing the vanes in contracted position in full lines and in projected position in dotted outline. Figure 5 is a View of one of the vanes removed from the remaining structure, the View indicating the Vmanner in which the vane operating rods are connected to the vanes. Y Figure 6 is an elevation View of a detail portion of the apparatus removed from the remaining structure.

Figure 7 is a sectional View on the line 7 7 of Figure 6. Y

Figure 8 is a sectional view through a portion of the control mechanism, the position of the section being indicated by the line 8 8 of Figure l. v

Figure 9 is a detail portion of the control mechanism removed from the remainder of the construction.

Figure lO is an end View of the control mechanism. Figure 11 is another detail portion of the control mechanism.

Figure l2 is a perspective view of one of the vanes detached from the remainder of the construction.

Figure 13 is a side elevational View of the coupling mounted for a typical use.

Figure 14 is an end elevation view of the arrangement shown in Figure 13.

The rotary hydraulic coupling is indicated in general by the letter A. The coupling includes two main sections, one of which comprises the hydraulic coupling body and which is indicated in general by the numeral 16. The other main part or section of the apparatus includes'the control apparatus and this is indicated in general, by the numeral 11.

The coupling body The coupling body 10 includes a drive shaft 12 having a slightly tapered socket 13 in its extremity. A sleeve 14 having a keyway 15 therein is provided with a tapered outer surface engaged in the socket 13 and includes an enlarged diameter externally threaded end portion 16. The outer end of the shaft 12 is also externally threaded with a left hand thread and a sleeve or collar 17 is threaded onto the sleeve portion 16 and the shaft 12 to hold these parts together. The sleeve is right hand threaded and left hand threaded, so that rotation ofthe sleeve is one direction draws the sleeve farther into the socket. As the keyway 15 forms a split in this sleeve, the sleeve may be wedged against a drive shaft inserted into the sleeve, to center this inserted shaft -in the shaft 112.

A disc like body portion 19 is attached tothe shaft 12, this disc actually forming a part of the hub. The

the hub 20 actually forming an extension of the shaft 3 s 12. 'Ihe hub or shaft portion20 is internally socketed asindicated at 21, the socket 21 extending axially into Y Ythe shaft portion 20 from the opposite end thereof from olmeans of the coupling. Obviously, a gear, sprocket or other take-olf means can be substituted for the pul- Y ley 26.V

The hub 22 is connected by a laterally offset portion 27 to a disc-like plate 29 which forms one side of the fluid housing, the housing being indicated in general by the numeral 30. The offset portion 27 is preferably stepped as indicated at 31 to fit with a running t about the disc portion 19 on the drive shaft 12. Cooling ribs such as 32 are preferably provided on the outer surface of the disc member 29, these cooling ribs preferably extending radially outwardly from the offset portion 27. The disc-like portion 29 supports an integral hollow cylindrical sleeve 33 which extends in concentric rela- 4 limit rotation. When the vanes are in fully projected position, the curved surfaces 55 of the vanes engage against the surface of the hub 20. Thus, these

surfaces

54 and 55 limit the pivotal movement of the vanes about their respective pivots 49.

As indicated in Figure 12 of the drawings, one end 56 of each vane 46 is ilat and from Figures 3 and 4 of the drawings it will be noted that the at ends 56 extend on substantially radial planes through the axis of the shaft when in fully projected position. As is also eviden-t from Figure 4 ofthe drawings, the dat ends 56 of the blades 46 engage in surface contact with the opposite end 57 of an adjoiningblade vwhen the vanes are in fully retractedposition. .The-outer surface S9 of each vane between the

ends

56 and 57 thereof lies on a cylindrical surface concentric with the hub 20 when the vanes are in fully retracted position. Stated otherwise, the vanes 46 are designed to engage in end to end relation when the vanes are retracted to provide a cylindrical continuous outer surface in this position of the vanes. Y Y

As is indicated in Figure l2 of the drawings, the body of each vane 46 is hollowon one side of the pivot aperture 47 so that this end of each'vane is extremely tion to the hub or shaft portion 20 forming a part of the drive shaft 12 and encircling this hub 20.' The fluid chamber is completed by a disc-like closure plate k34 which is connected to a generally conical portion 35 vwhich terminates in a hub 36 encircling the extended end 37 of the hub or shaft portion 20. An anti-friction bearing 39 encircles the shaft portion 37 to provideV a means of permitting relative rotation between the shaft and the fluid chamber. A seal 40 is also provided in the groove 41 in the inner surface of the hub 36 to preven the leakage of fluid from the uid chamber. f

.The closure plate V34V is connected to the disc-like closure 29 by means of bolts 42 or other suitable means.

VThese bolts 42 are arranged in angularly spaced relation about the periphery of the fluid chamber as is indicated in Figure 2 of the drawings. Y V

Angularly spaced fins 43 are provided on the inner surface of the disc-like closure member V29 and extend in a generally radial direction.Y Fins 44 are alsoY provided on the inner surface of thersleeve 33, the fins 44 forming an extension of the iins 43. VFins 4S are also provided on the inner surface of the closure plate 34, the fins-45 being arranged to extend in-a generally radial direction. These fins are designed to act somewhat in the capacity of the blades of la turbine and cause the fluid chamber to rotate with the hub 20 in the operation of the coupling in a manner which will be later described in detail.

A series of angularly spaced vanes indicated in general by the numeral 46 `are pivotally connected to the disc 19 to encircle the hub 20. These vanes are shaped as is best illustrated in Figure 12 of the drawings. The

vanes 46 include a pivot opening 47 designed to accommodate pivot bolts 49 which extend through angularly spaced apertures 50 in the disc 19. The pivot-bolts 49 extend in a direction parallel to'the axis of the shaft portion 20 and include a head 51 which engages the vanes to hold the same in place. 'I'he bolts 49 are held in place by suitable nuts 52 which are located in recesses `in the disc 19. Y

'I'he vanes 46 are provided with arcuate portions 53 having the axis of the pivot aperture 47 as their center of arcuation. Oppositely

curved surfaces

54 and 55 are provided on opposite sides of the curved portion 53, these oppositely curved portions being of substantially the same radius of curvature as the hub 20. With reference to Figure 4'of Y.the drawings, it will be seen vthat when the vanes 46 are4 in fully .retracted position, thecrved surface 54 'engages .against .thel 1ub-20 Vto 'relation to the shaft portion 37 light in Weight. Theportion 60 of each vane adjoining the end 57 thereof is formed Yof a material substantially heavier than the remainder of the vane. In other words, if the vanes 46 Yare made of a lightweight vmaterial such as magnesium or the like the other end 60 of each vane may be formed by a relatively heavy metal such as lead or the like. As'is indicated in Figure l of the drawings, semispherical sockets 58 are cast into the hollow interior of each vane. As is indicated in Figure 5 of the drawings, an internally'threaded cylindrical passage 62 leads into the socket 58. VAn operating arm 63 having a ball head 64 is engaged in each socket 58 and a threaded plug 65 is threaded into the passage 62 to engage' against the ball 64 and to hold the4 ball in place in the socket. Preferably the inner end of the plug 62 s concave to t the curvature of the ball 64 to provide the operating arm 63 with a suitable socket so that it canY change angularity relative to the connected vane.

The control mechanism The control mechanism "11 includes a sleeve 66 which encircles the drive shaft portion 37. Anti-friction bearings 67 and 69 are provided within the sleeve 66 and encircling the shaft portion 37 to provide relative rotation between these parts. A'seal 70 is preferably provided outwardly of the hub 36. A spacing sleeve 71 is provided between thebearings 67 and'69. A nut 72 is provided on the externally threaded end of the shaft portion 37 to hold the bearings 67 and 69 in proper The outer race of the bearings 69 engages against an internally projecting ange 73 integral with the sleeve 66 and a spacing sleeve 74 is provided between the'outer races ofthe bearings 67 Vand 69. A radially extending lubrication passage 75 closed by a plug 76 or other suitable means provides a way of lubricating the bearings when it is desired.

A shaft 77 is slideably supported in the socket 21 extending into the shaft portion 37 and the hub 20. An

annular groove 79 in the shaft 77 supports a seal 78 between the shaft 77 and the shaft portion 37 The portion Vwhich Vencircles a portion of the shaft portion 37 and the hub 20. As a result of this arrangement, the flange 84 on the sleeve 85 mayy slide longitudinally of the hub 20 and may rotate to some extent relative to the hub 20 fo a purpose which will be later described. The limits of this relative rotation is defined by the longitudinal edges of the apertures 80 on opposite sides of the shaft portion 37.

As shown in Figure 1 of the drawings, the connecting or operating arms 63 are provided with enlarged ends 89 having pivot apertures 90 extending therethrough. These enlraged ends 89 are provided with parallel sides which engage between the flat sides of the radial grooves 92 arranged in angularly spaced relation in the flange 84. Pivots 93 (Figure 2) pivotally support the `arms 63 and connect these arms for movement withA the ange 84 and slideable sleeve 85. A `piston 94 is slideably supported within the sleeve 66 and includes a ring shaped body 95 having an inwardly extending ange 96 which engages against a shoulder 9 7 on the shaft portion 77. A bearing 99 is interposed between the ange 96 Aand spacing washers 100, these washers being held in place by a nut 101. 'Ihus the piston may rotate relative to the shaft 77 but moves longitudinally in unison therewith.

As is best illustrated in Figure 11 of the drawings, the piston 94 is provided with a groove 102 which extends along a chord of the cylindrical outer surface of the piston, the groove having its side edges parallel with the

ends

103 and 104 of the piston. A slide 105 is provided in the groove 102, the slide 105 having a cylindrical pivot opening 106 therein extending normal to the base of the groove 102. This aperture 106 is designed to accommodate an eccentric pin 107 mounted on the cam 109 which is shown in Figure 8 as being pinned at 110 to a shaft 111. Rotation of the cam 109 thus acts to reciprocate the piston 94 axially, the slide 105 moving in the groove 102.

As is indicated in Figure 8 of the drawings, the shaft 111 extends through the plug 112 mounted in a tubular portion 113 of the casting 114 forming the enclosure for the control mechanism. As is indicated in Figure l of the drawings, the casting 114 includes two right angularly extending

tubular portions

66 and 113 the axes of which intersect. The casting also includes a pair of lugs or

brackets

115 and 116 through which the operating shaft 117 extends for support.

The shaft 111 is supported by bearings `119 and 119. The end portion of the plug 112 includes a reduced-diameter sleeve element 120 which serves as a bearing for the hub 121 of a gear 122. 'Ihe shaft 117 vis parallel `to the shaft 111 and a gear 123 has its hub 124 mounted upon the shaft 117 for rotation in unison therewith. Rotation of the operating shaft 117 thus acts through the gear 123 to rotate the meshing gear 122.

As is indicated in Figure of the drawings, taken in conjunction with Figure 8, a disc 124 has its hub 125 keyed to the shaft 11 as indicated at I126. The disc 124 is provided with a pair of diametrically :opposed notches 127. Pins 129 are mounted in the gear 122 and project into the notches 127. As the notches are substantially wider than the diameter of the pins 129, the disc 124 may rotate angularly for some distance relative to the gear 122. This provides a lost motion arrangement which assists in the operation of the construction as will be described.

Operation of the coupling The coupling is mounted in a suitable position. A power shaft is inserted Within the sleeve 14 and the sleeve wedged between this power shaft and the drive shaft 12. The pulley 26 is attached to a driven member which is to be driven at a variable speed.

By rotation of the control operating shaft 117, rotation may be transmitted through the gears ,-123 and 122 to the parallel shaft 111 through the disc 124. Rotation of the gear 122 brings the pin or pins 129 to one end of the slot 127 and further rotative movement of the gear in the same direction will act through the disc to rotate 6 the shaft 111 and the eccentric disc 109 attached thereto.

Rotation of the eccentric disc 109 acts through the pin 107 and its bearing 105 to move the piston 94 longitudinally of the cylinder in which it is positioned. Longitudinal movement `of the piston 94 moves the driven shaft 77 longitudinally within the axial socket of .the hub 20 and its driven shaft extension 37.

Movement of the rod or shaft 77 in one direction acts to move the sleeve which is connected by the arms 63 to the various vanes 46. Thus, movement of the member 77 in one direction acts to swing the vanes 46 toward retracted position so that the outline of the vanes forms a cylindrical surface. Accordingly, when the shaft or rod 7 7 is in its outermost position, the vanes are fully retracted and rotation of the hub 20 and the vanes will cause insuthcient movement of the fluid within the fluid chamber' to move the housing 30 in unison with the vanes.

Rotation of the control rod 117 in the opposite direc* tion acts through the lost motion mechanism described to move the sleeve 85 inwardly. 'Ihis motion acts through the rod 63 to urge the hollow ends of the vanes outwardly. As the vanes move outwardly, they create a force against the liquid within the housing 30 tending to rotate this body of liquid with the vanes, The moving liquid acts against the internal ribs in the casing 30 to rotate the housing or casing. If the vanes are but slightly projected, the housing will rotate at a relatively low speed. As the ends of the vanes are projected a greater amount, the tendency for the liquid in the casing to rotate the casing increases, until when the vanes are virtually fully projected, the casing will rotate at almost the same speed as the drive shaft.

From the foregoing description it will be seen that a variable speed drive is provided which can rotate the driven member at a desired speed, and this speed may be regulated by operation of the control mechanism. If the load upon the driven member remains substantially constant, the lost motion mechanism which has been described has little effect upon the operation.

It will be seen that as the vanes rotate, the force of liquid against the operating or outer ends of these vanes tends to swing the vanes toward fully projected position. At the same time, centrifugal force acting upon the weighted opposite or inner ends of the vanes tends to swing the vanes toward a closed or retracted position.

In the event the driven member is operating at a predetermined desired rate of speed and a heavy load is suddenly applied -to the driven member, this load tends to hold the driven member Vand casing from rotation. The reduction in speed-of the outer casing imposes a greater force upon the outer or projecting ends of the vanes. When this force is sufficient, the vanes are permitted to move outwardly by the lost motion mechanism previously described. In Vother words this pressure acts upon the connecting rods 63 to move the shaft or rod 77 inwardly, this motion acting through the eccentric to rotate `the shaft 111 through the angular distance necessary to move the pin 129 from one end of the slot 127 to the opposite end thereof. By increasing the extent of projection of the vanes, these vanes will exert a greater force against the liquid in the housing 30 until the housing again rotates at the desired speed. When the pulley attains the proper speed, the force upon the vanes decreases and the centrifugal -force on the weighted ends of the vanes tends to retract these vanes. In other words, when the driven member is adjusted to rotate at a desired speed, the vanes are not rigidly held at a predetermined degree of projection from their hub and there is at all times a balance between the lcentrifugal force acting on one end of each vane and the uid pressure acting upon the other end thereof. When the load upon the driven member lessens,-the effect of centrfiugal force overbalances the force acting upon the vanes, acting to retract the vanes within the limits of the lost motion mechanism. As a result, during operation, the pin 129 of the lost motion mechanism merely oats between its two extreme positions moving in one direction when the load fon the driven member'increases and moving in the opposite direction when the load on the driven member decreases.

In accomplishing the result described, a careful balance between the weighted ends of the vanes and the hollow outer or projecting ends of the vanes is necessary.

However, in actual practice it has been found that when a load is applied to the driven member, the lost motion mechanism will quickly correct any variation in speed of the driven member by projecting the vanes to a greater extent. As theY load eases oi, the lost motion mechanism acts to retract the blades to some extent due to the counterbalancing effect of the weighted ends of the vanes thereby providing a variable speed mechanism which functions effectively for its intended purposes. g

Manner ofrmozmling The manner of mounting the clutch mayA be varied Within'substantial limits. In Figures-713 and 14 is a typical mounting arrangement is shown. A ring 132 having holes 133 in angularly spaced relation therethrough is supportedV by arms 134 to a fixed platform V135 forming a part of the frame 136. The coupling A is driven by a motor 131 on the frame 136. The coupling is connected by belts 139 to a counter shaft 130, to drive this shaft.V Y

The control shaft 1'17 extends through an arm 140 having an internally threadedA axial socket to accommodate a thumb screw 141. This thumb screw may hold the shaft 117 in any angular position, so'that the adjustment may vary through 360 degrees.Y In this way the operating 'handle may be positioned to suit the convenience of the Jperator. Y l Y i The clutch is enclosed within an outer shell 143 includ- 'ing a disc 1,44 secured to the sleeve 66 by bolts 145 and also including a cylindrical sleeve 146V connected at one end to said disc and encircling the housing. The disc 144 is provided with angularly spaced yapertures 147- therethrough spaced from the periphery thereof. The other end of the sleeve 146 is open. Rotation of the housing withinthe shell acts to draw air through the apertures 147 and force Vair through Vthe open end of the shell sleeve 146. Y f

Due to the fact that theV sleeve 66 is rotatable relative to the driven shaft and the driven housing, some means must be provided for holding the sleeve 66 from rotation. By providing the ringY 132 adjacent the contro1 Y shaft Y117, and connecting the arm 140 encircling the control shaft to the ring, the shaft 117 may be secured to trifugal force acting upon the weighted ends of said vanes tending to counter balance the force of hydraulic fluid against therprojectable ends of thevanes, means for simultaneously pivoting said vanes toward projected or retracted position, fand lostV motion means in said vane pivoting means, said lost motion means permitting some variationV in the projection of said vanesrat a predetermined position of a portion of said Yva'ne pivoting means whereby an increase in the load resisting rotationof said housing tends to project said vanes and a reduction in load resisting rotationY of said 'housing tends Yto retract said extend in any direction. The entire control, including the Y Y sleeve 66 and shell 143 may be pivoted about the axes of the drive shaft and housing when these elements are not in operation. l

In accordance with the patent statutes,` I have described the principles of construction and operation of my improvement in rotary hydraulic couplings, and while I have endeavored to set forth the best embodiment thereof, I desire to have it understood that changes V.may be made within the scope of the following claims without departing from the spirit of my invention.

I claim: Y

1. A rotary hydraulic coupling including a drive shaft, a housing encircling a portion of said drive shaft and o being relatively rotatable with respect thereto, a series of vanes within said housing, pivot means pivotally con-Y may be'forcedV against Vsaid fins by jsaidyaneathe .Ceu- P vanes.

2. The construction described in claim 1 and in which said vanes are angularly spaced about said drive shaft and arershaped to provide a cylindrical outer surface in fully retracted position. i i i i .v

3. A variable speed device including a rotatable drive member, a coaxial relatively rotatable driven member, one of said members including an outer rotatable housing havingspaced sides and a connecting peripheral sleeve connectingsaid sides, theV other of said members including Ya hub extending within said housing, vanes supported on said hub to extend koutwardly therefrom vwithin said housing, means pivotally supporting said vanes,rmeans connecting said vanes for pivoting the same in unison, a control connected to said connecting means to Iactuate the same, said control being pivotal relative'to said drive member and said driven member about the axis thereof when said drive member and driven member are Vstationary, an outer shell spaced from and encircling said housing and connected to said control'and pivotal in unison therewith, said shell including a disc having angularly spaced apertures therethrough Vspaced from the periphery thereof and, said shell also includinga cylindrical sleeve connected atone end to said disc and encircling said housing, said sleeve having Van open end opposite the end thereof connected to said disc, whereby rotation of said housing within said shell will act to draw air through said apertures and force air through said open end of said shell sleeve. i i

4. The structure of claim 3 and in which said means connecting said vanesris movable in a directionaxially of said drive and driven members. i

5. A rotary hydraulic coupling including ardrive shaft, a rotary housing encircling said drive shaft, internal ribs on the interior of said housing, a series of vanes pivotally Vconnected to said drive shaft on axes substantially parallel to the axis of said drive shaft, ksaid vanes being pivoted intermediate their ends and having inner ends substantially sealed relative to said drive shaft, said vanes, in one extreme position, forming `a rotor having a substantially continuous cylindrical .outer surface, an arm pivotally connected to each vane for controlling the pivotal position thereof, an axiallyY movable control member to which each said arm is connected for movement, means externally of said housing connected to said axially movable member for moving the same, lthe innerV ends of said vanes being weighted, whilerthe outer vane ends are relatively light, wherebythe action of centrifugal force tends to urge the vanes toward retracted position.

6.V A rotary hydraulic coupling-including a drive shaft, a rotary housing encircling said Vdrive shaft, internal ribs on the interior of said housing, a series of vanes Ypivotally connected tol said drive shaft on axes substantially parallel to the axis of saidrdrive shaft, said vanes being pivoted intermediate their ends and ha'yingy inner ends substantially sealed relative to said` driveV shaft, said are relatively light, so that the action of centrifugal force .tends to urge the vanes toward retracted position, and including a lost motion mechanism between said arms and said means externally of said housing.

7. A rotary hydraulic coupling including a drive shaft having a cylindrical outer surface, a fluid containing rotary housing encircling said drive shaft, internal ribs on the interior of said housing, a series of vanes pivotally connected to said drive shaft on axes substantially parallel to the axis of said drive shaft, said vanes being pivoted intermediate their ends and having inner ends including arcuate portions substantially sealed relative to the cylindrical outer surface of said drive shaft regardless of the pivotal position thereof, said vanes each having an arcuate side, the center of arcuation of said sides being at a common point when said vanes are in one extreme position to provide a continuous substantially cylindrical outer surface, a at portion of the inner end of each vane abutting against a flat portion of the outer end of the next adjacent Vane in said one extreme position, said vanes having substantially at ends extending in substantially radial planes through the shaft axis in their other extreme positions and means connecting said vanes for operation in unison.

8. The structure of claim 7 and in which said vanes are so shaped and supported that reaction of iiuid against the vanes caused by rotation of the vanes tends to pivot the vanes toward the other extreme position, and in which the inner ends of said vanes are weighted, whereby centrifugal force tends to urge said vanes toward said one extreme position.

9. A rotary hydraulic coupling including a drive shaft, a uid containing housing encircling said drive shaft, internal ribs on the interior of said housing, a series of vanes, means pivotally connecting said vanes to said drive shaft on angularly spaced axes about, and parallel to said drive shaft, said vanes being pivotal between two extreme positions, said vanes being substantially sealed relative to said shaft in all positions, means for pivoting said vanes in unison, said vanes having one substantially at end projecting on a substantially radial plane through the shaft axis outwardly from said shaft in one extreme position, the ends of said vanes abutting in the other extreme position thereof, said vanes having an arcuate outer surface forming a substantially continuous cylindrical surface in said other extreme position of said vanes, said other ends engaging said shaft in said one extreme position to limit pivotal movement thereof.

10. The structure of claim 9 and in which each said vane includes an inner arcuate surface in tangential relation to said shaft and forming the seal between each vane and said shaft.

ll. A rotary hydraulic coupling including a drive shaft, a housing encircling a portion of said drive shaft and being relatively rotatable with respect thereto, a series of vanes Within said housing, pivot means pivotally connecting said vanes to said shaft for rotation in unison therewith, the axes of said pivots extending substantially parallel to the axis of said drive shaft, said pivots extending through said vanes intermediate the ends thereof, said vanes having outer projectable ends and inner weighted ends, said weighted ends being substantially heavier than said outer projectable ends, said housing having internal tins and including hydraulic fluid which may be forced against said tins by said vanes, the centrifugal force acting upon the weighted ends of said vanes tending to counter balance the force of hydraulic iluid against the projectable ends of the vanes, means for simultaneously pivoting said vanes toward projected or retracted position, whereby an increase in the load resisting rotation of said housing tends to project said vanes and a reduction in load resisting rotation of said housing tends to retract said vanes.

12. The structure of claim 11 and in which the inner weighted ends are substantially sealed relative to said drive shaft.

13. The structure of claim 11 and in which said outer projectable ends on said vanes are provided with surfaces on planes substantially through the axis of the drive shaft in projected position.

References Cited in the le of this patent UNITED STATES PATENTS 895,491 Nash Aug. 11, 1908 1,192,233 Severy July 25, 1916 1,258,468 Rounds Mar. 5, 1918 1,901,988 Rudqvist M-ar. 21, 1933 1,940,918 Petroni et al. Dec. 26, 1933 2,292,482 Roche Aug. 11, 1942 2,333,674 Powell Nov. 9, 1943 2,382,034 Wemp Aug. 14, 1945 2,409,374 McGill Oct. 15, 1946 2,587,154 Hartz Feb. 26, 1952