US 2570768 A
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ROTARY TURBINE-TYPE HYDROKINETIC COUPLING- Filed Feb, '3, 1947 v 2 sheets-sheet 1 ltorney ROTARY TURBINE-TYPE HYDROKINETIC COUPLING Filed Feb. 3, 1947 2 sheets-sheet 2 Inventor Attorney Patented Oct. 9, 19,51
ROTARY TURBINE-TYPE HYDROKINETIC COUPLING Robert Cecil Clerk, Richmond, England Application February 3, 1947, Serial No. 726,012
In Great Britain November 12, 1945 section 1,'Pub1ic Law 69o, August s, 1946 Patent expires November 12, 1965 `This invention relates to hydraulic couplings, and has reference to a power transmitting appliance in the form of a coupling, brake or gear` of the so-called hydro kinetic type, that-vis, one in which power is transmitted by the kinetic energy of a liquid discharged by an impeller on a drive shaft against the vanes of a turbine runner on a driven shaft. The invention is concerned in particular with a hydro-kinetic couplingof the kind in which a reservoir chamber for the operating liquid, e. g. oil, is provided within the compass or conines of the rotating casing of the coupling. In prior proposals the reservoir chamber has been disposed at the rear ofthe runner or driven part or at the rear of the impellerl or driving part, and has been connected with the Working circuit of the coupling to permit of the vpassage of liquid from the working circuit vto the reservoir, and vice versa. This interconnection has been effected hitherto by means of a number of tubes which extend between the reservoir chamber and the vortex core ring of the coupling. The uses and advantages of such a reservoir chamber are, of course, well known, the objects of the chamber being briefly to remove part of the oil from the working circuit under starting conditions thus assisting the engine to pick up the load more readily by reason of the reduction in drag torque or tendency to creep, and then/ when a certain speed ris reached', to return the oil into the-working circuitautomatically, which results in a low slip value under normal running conditions. The reservoir serves also to separate air from the oil in vthe working circuit and` to prevent undue Y pressure rise in the coupling by acting as an expansion chamber. 1
It is an object of the present invention to provide a simple and sturdy construction of hydrau lic coupling of the hydro-kinetic type which possesses all the advantages which accrue from the provision of a reservoir chamber within the rotating casing thereof without having to incorporate tubes specially provided on either the impeller or the runner for engaging the operating liquid contained within apart of the cou,- pling which is rotatable with the complemental member (i. e. the runner or the impeller as the case may be) for the purpose of withdrawing said liquid from the working circuit of the coupling.
Another object of the present invention is to provide a hydro-kinetic coupling having the characteristics already referred to without the necessity of using a vortex core-ring, which has 2 Y hitherto been the part of the Working circuit of the coupling between which and the reservoir chamber the liquid withdrawing means has eX- tended.
A further object of the invention Yis to provide a 'hydro-kinetic coupling constructed so as to permit the operating liquid to move freely into the reservoir under starting conditions and to return automatically to the vortex chamber when the coupling is rotating at or above a predetermined regulatable speed.
The foregoing and other objects of the invenlf tion and a fuller understanding thereof may be had by referring to the following description and the accompanying drawings in which Figures 1 and 2 are similar longitudinal cross sections, partly in elevation, showing two suitable constructional forms of the coupling. f k
In the constructionillustrated in Figure 1, the impeller I has a peripheral flange 2 by means of which it is clamped between the joint faces of the two halves 3, Il of a transversely split l casing, one side of the casing half 3 being bolted` to an end flange 5 of a drive shaft 6. Adjacent to the peripheral flange 2' of the impeller I a trough I of approximately semi-elliptical'form is provided, and opposed to this is arranged the outer approximately semi-elliptical trough 8 of a runner 9. The runner 9 is anchored by means of a centrally apertured plate portion I0 to a driven shaft II, which extends centrally through the casing and is rotatably supported coaxially withfthe driving shaft 6 by an extension I2 running in an anti-friction bearing I3 mounted in casing half 3, i. e. on the driving shaft side of the casing, and by a journal I4 running in an anti-friction bearing I5 mounted in the casing half L An oil retaining seal 'I6 is provided around a collar I'I on the runner shaft II on the outside of the bearing I5. Thel impeller I is provided with a centrally apertured flange I8 somewhat similar to the plate I0 of the runner B and the flange I8 and plateportion I0 of theimpeller I and the runner B respectively are spaced apart to'form a duct I9. The general direction of the duct i9 is disposed so as to be substantially or approximately tangential to the' cross section of the vortex, vso that oil may freely leave the circulating vortex without setting up any disturbance in the vortex flow. The inner edge 20 of the impeller flange I8 forms a weir over which oil flows directly into the reservoir chamber 2l. The edge 20 of the impeller I is curled back toward the duct I9 and thus provides behind the flange I8 an annulus within which turbulence of the oil is set up. This turbulence has the effect of opposing the low of oil between the vortex chamber and the reservoir. The outer part of the casing lies in proximity to the outer part of the clamped impeller Il, the reservoir '2l being; provided. in. the region of the inner part of7 said impeller. One or more centrifugally operating valves 22 of any suitable construction may be carried in bosses 23 formed on the rearside of.' the impeller I, each valve 22 serving to control a passage 24 which opens into the vortex space between the opposed impeller I and runner 8; each passage 24 is formed and disposed so; as; to. ensure thatany oil passing from the reservoir. ZIx through. the valve 22 When it is opened. by centrifugal action at a predetermined speed enters smoothly by a tangential inflow movement into the circulating vortex. These control valves:v 2'2 are; optional.
In` Figure 2 of the drawings an alternative construction is illustrated in which an adjustable Weir ring 25 is employed instead of. the static curled-edge flange I8 shown in Figure l. rLhe Weir ring 25- is normally held by spring-loaded bolts 2liv against a web 2'! formedonthe inside periphery of the impeller1 trough 'I and. ismain-l tained thus during the low speeds which; prevail under starting conditions. As the.- speed of rotation. increases during operation of the coupling the Weir ring 25 slides over the seating rim. 2S against the resistance of the spring-loaded. bolts 26 and thus reduces the- Width of the duet I9, thereby producing substantially the same throt.- tling eiect as the turbulence' created by the curled-edge ange I8 in` the construction shown in Figure. 1. This sliding movement. of the Weir ring 25 is brought about by the: influence of centrifugal force of the oil. trapped behind it and of forces dueto the convergentFdivergen-t ovv of: oilpast the ringY face and runner flange.
With this Weir ring 25 the same forma of. centrifugally operating valve. 22 may be used as illustrated diagrammatically in Figure 1,. or a1.-
ternatively as shown in Figure. 2, a ring. valve may be employed. This ring valve 29 comprises a ring 29 which is.v rotatable on. a seating 30 inthe casing half 4, in close or rubbing contact with a ported face 3| on theback. of the impeller I. The ring 29 is provided Witha series of spaced apart arcuate slots- 32 or equivalentl openings arranged concentric to the axis of rotation of the impeller I and adapted on rotation; of the ring. 29 to.- align or register with the tangential passages 24 which open out on the ported face. 3l.
A rotary movement is imparted. to the valve ring` 29v at and above a predetermined operating speed by connecting it to one arm. of at least one bell` crank, lever 33, each mounted for free pivotal. movement on a pivot 34 on. the back of the. impeller trough l., the in-uence of centrifugal: force on a weight 35 on the other armof said'v lever 33 being utilised to swing said lever about its pivot 34- and. thus impart rotation to the valve ring 29. This form of centrifugally operated ring valve could be employed with a coupling of the construction shown in. Figure l, in lieu of the valves 22.
1. A hydro-kinetic coupling comprising adrive shaft, a` closed casing secured to said drive shaft, a driven. shaft coaxial with the drive shaft and journalled Within said closed casing for rotation independently thereof, a substantially semielliptical shaped troughed runner secured to said driven shaft and disposed with its back adjacent to the Wall of one side of the closed casing, a sullstantiallyA semi-elliptical shaped'. troughed impeller secured partition-Wise within' the closed casing and having a central aperture for the passage therethrough of said driven shaft, said impeller' being' disposed so as to form an oil reser- Voir between the back thereof and the other side of the. closed casing, and said troughed runner and troughed impeller facing one another to form therebetween. a substantially elliptical shaped vortex chamber and being constructed to constitute between them a duct which is disposed substantially tangential to the cross-section of the vortex and Which forms, a continuous uninterrupted flow-restricting Weir around the Adriven shaft, over which Weir operating liquid directly passes fromfsaid vortex: chamber to: said` oilreservoir and. the back of the outer peripheral portionx of said impeller having a. plurality of' centrifu-l gally operable ports disposed substanti'ally` tane gentia-l tol the cross-section. of the Vortex chaine ber for providing asmooth tangential inflow movement of oil from said. reservoir. intothe; circulating; vortex under the effect of centrifugal action..
2.. A` hydro-kinetic. coupling as claimed in. claim 1, wherein. the impeller is. provided with an in-V y wardly directed. ange. having an incurled. edge forming an. annulus around the-lip: of the aper ture, through. which the operating. liquid iievvsv directly into. the reservoir from thefvortex cham* ber. formed between .the opposedimpeller and runner, saidannulus setting up turbulence-which opposesl the flow of the liquid into said. reservoir. in. excessy of predetermined flow velocities.
3. A coupling according to.- claim- 1.,. wherein a Weir ring is mounted for axial displacement inthe central aperture of. thefimpeller.
4.. Av coupling according to claim` 3, in which the Weir ring is slidably mounted. in. the central aperture of. the impeller,` for axial- .displacement under the influence of centrifugally imparted hydraulic forces, to restrict. said impeller aper.- ture, for the purpose of throttling the. flow of operating liquid from the` vortex chamber into the reservoir.
5.v AI coupling according to claim 1-,v in which the porting provided. in. the backof the impeller is controlled by valvel means constructed; for ad.- mitting liquidv fromv the reservoir into the vortex chamber, said. valve means. operating automatically to pass liquid therethrough when. the impeller is rotating above a predetermined speed..
ROBERT CECIL' CLERK.
REFERENCES CITED The following references are of record` in. the. file. of this patent:
UNITED' STATES PATENTS Number Name Date 1,963,720 Sinclair June 19., 1934. 2,127,738 Kugel Aug. 231938 2,128,828 Klepper Aug. 30, 1938v 2,181,711 Sinclair Nov. 28, 1939 2,280,042 Duiield Apr. 14, 1942' 2,384,282. Peterson et. al. Nov. 16,1948