US2351517A

US2351517A - Turbotransmission

Info

Publication number: US2351517A
Application number: US366949A
Authority: US
Inventors: Jandasek Joseph
Original assignee: Bendix Aviation Corp
Current assignee: Bendix Aviation Corp
Priority date: 1940-11-25
Filing date: 1940-11-25
Publication date: 1944-06-13
Anticipated expiration: 1961-06-13

Description

June 13, 1944. JANDASEK 2,351,517

TURBO TRANSMISSION Filed Nov. 25, 1940 J INVENTOR 053 JZWJQJe/f BY M, 6M4 9 ATTORNEYS.

Patented June'13, 19 44? I UNITED STATES PATENT orrlce rurmo'rmnsmssron Application November 25, 1940, Serial No.366,949 v 8 Claims (.Cl. 103-115) This invention'relates to transmissions and more particularly to fluid transmissions which transmit power! i'romone shaft to another through a circulating liquid;

An-obiect of this invention resides in the provislon of fluid directing blades or vanes designed and proportioned in such a manner as to impart to or absorb maximum energy from a circulating liquid by rotatable impeller or turbine members.

imparted to the circulating liquid as. the liquid leaves the impeller blades thereby equalizingg Otlrer objects and advantages of this invention will be apparent from the following detailed description considered in connection with the accompanying drawing, submitteddor purposes of illustration only, and not intended to define the Another object of the invention is to provide w scope of the invention, reference being had for fluid directing vanes of eflicient fluid foil shape which accurately conform to the contour of the fluid circulating passages of the device,

A further object of the invention resides in the provision of fluid directing vanes of efflcient fluid l foil shape designed in such a manner that their center lines correspond with the theoretical that purpose to the subjoined claims.

In the drawing wherein similar reference characters refer to similar parts throughout the sevthe impeller blade and turbine vanes.

Fig. 2 is a sectional View taken substantially on the line we, of Fig. 1, showing the first stage A still further objectis to provide a. turbine turbine vane it having a straight centerline bladedesign for a fluid transmission wherein a fluid foil shaped blade of efllcient design is contoured in such a manner that its theoretical center line accurately corresponds to the theoretibefore it is bent.

' Fig. 3 is a view similar to Fig. 2 takensubstantially on the line stir of-Fig. l. of the same vane after its center line 38 has beenbent to form a.

cal maximum efliciency flow curves of-the turbo- 5 001110811 c e 3% vf'two-dimensional formdevice operating with substantially predetermined entrance and discharge angles.

Yet, a still further object is to form a turbine vane from an efllcient fluid-foil shaped-member Fig. 4 is a section through the second stage turbine vanes it taken on the line dllc of'Fig. 1

. illustrating the vane in the two-dimensional form as if the center line a of Fig. 1 were a straight wrapped around a conical curve such for example so line.

as a parabola or hyperbole. to provide an emcient turbine energy absorbing vane.

Still another object 01 the invention resides, in the provision 01' emcient impeller blades generated Fig. 5 is a side view of the vanlB looking axially from the discharge end. Fig. 6 is a view similar to Fig. 1 looking; in the opposite direction representing the vane [8 as if by wrapping 'the theoretical axis of fluid fo il as all po s of the vane were turned in one p a impeller blades shaped to transmit energy to liquid in the most efllcient manner.

Another object of theinvention resides injthe provision of impeller bla des ofeflicient fluid foil 40 to the direction of rotation throughout except.

shape having theoretically substantially straight center lines for a major portion oftl eir length and curved center lines to varythe fluid energiz- A further object or this invention-is to provide Thisview represents one step in laying out the vane.

blade 20 having approximately a. pitch angle Y thetail end of-the blade. I Fig.8 is a three-dimensional view of the blade 20 wrapped. around an i'nvolute curve. Profile 54 represents the same blade as in Fi 7 having a 45 pitch angle of approximately 45? in the portion adjacent the web, and a profile 53 adjacent the shroud of a pitch angle of approximately 30. Fig. 9 is a view similar to Fig. 8 showing a com- I .plete impeller vane having suitable means for an impeller fluid-energizingblade-having a con-' '50 attaching it in the impeller Shroud and web memtoured form soproportioned that energy may be transmitted to a circulating medium throughout the ,n iajor length of the blade and wherein the trailing edge of the blade is contoured angularly; in such a manner that substantially no-energy is bers. H

v Before explaining in. detail the'present invention it is to be understood that the invention is notlimited in itsapiifitzation-to the details oi: cori- ,struction and arran ement of parts illustrated in Fig. 7 illustrates a two-dimensional impeller" the accompanying drawing, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also it is to be understood that the phraseology or terminology employed herein is for the purpose of descrip- The driven shaft I4 is provided with a turbine hub l5 which carries a second stage turbine web 16 separated from a turbine shroud member I 1 by means of second stage turbine vanes 18. The turbine shroud I I is also provided with first stage turbine vanes I9. e

The impeller housing ll is provided with a plurality of spaced fluid energizing blades 20 interposed between the housing II and an impeller shroud 2|.

In the operation of the device liquidis transmitted from the second stage turbine vanes It to the impeller vanes 20 where it is energized by centrifugal force due to rotation of the impeller housing ll and theimpellerblades 20. The energized liquid is then transmitted to the first stage turbine vanes l9 and is thereafter directed to the second stage turbine vanes II to transmit energy through the turbine hub shaft ll.

A stationary member 22 is concentrically mounted relative to the driven shaft H. A hub member having external helical threads 24 formed thereon is mounted on the stationary l5 to the driven sleeve 22 and is separated therefrom by one-way brake means 25 whereby the hub 23 may-rotate freely in one direction but is restrained from rotation in the opposite direction.

position a guide Wheefchannel 29 in the power transmitting fluid circuit preferably between the first and second stage-turbine vanes I! and II respectively.

. Referring now to Fig. 2, attention is called to the fact that in the formation of the first stage.

turbine vanes I 9 a fluid foil shape of suitable contour is selected. The fluid foil has a center line 30 extending therethrough, and contoured front and rear surfaces 3| and 32 proportioned to absorb energy from'a circulating liquid. The shape of the fluid foil section is selected to vary dependent on the speed of the-flow of liquid over the vanes and the viscosity of the liquid utilized.

Referring to Fig. 3, it will be observed that the center line 30 of the vanel9 is wrapped around a conical curve such for. example as a parabola or hyperbola wherebyit has a. center line 30b which in onedimension follows the theoretical center line 30a in .the first stage. turbine. .Thevane illustrated in Fig. 3 is a two-diof the second stage turbine vanes 18 which may beof relatively thin cross section. Referring to Fi 4, it will be noted that the blades I8 have center lines 40 corresponding generally with the center line 40a of the second stage turbine vanes 18 as illustrated in Fig. 1. These vanes are substantially axial inform and are designed to have working surfacesat the discharge jend corresponding generally to the surface of a screw; This working surface may be generated by extending an axis BB to-cut the axis O0.of the turbine. The axis -B- ,-B then curves around the axisO-O and moves longitudinally of the device Towards the end of the vane the turnin and moving of the axis BB is substantially uniform and generates a true screw formas illustrated by the axial positions .aa, bb' and the distance 0-42 of Figs. 4 and 5. As the movement progresses the turning and movement of the axis increases and the generated surface approaches that of a screw with non-uniform pitch as illustrated by the positions of the axes c-c d-d', e--e', etc. which lie on the curve 40a which represents the center of the fluid channel.

i 4' is a two-dimensional view as if the center line 40a of the'vane I8 were a'straight line, the vanes having inlet and dis'charge angles as illustrated. Fig. 5 is a side view of the actual three-dimensional vane, and Fig. 6 is a hypothetical view (not a. true geometrical view) illustrating the vane as if all the points 'of the vane were turned in one plane.

- Referring now to Figs. 7 to 9 inclusive, it will be observed that the impeller blades 20 are formed by selecting a-suitable air foil shapeset at a suitable pitch angle 5| relative to the di-' rection of rotation 5Ia as illustrated in Fig. 7 with a theoretical center line positioned at a suitable angle 5| to the direction of rotation 5la. It will be observed that the center line 50 is substantially straight throughout the major portion of the length of the blade 20 and that it tapers oif as illustrated at 52 to reduce the fluid energizing characteristics of the vane and to equalize the fluid pressures in the fluid circuit adjacent the. impeller outlet.

Referring to Fig. ,8, it will be observed that' the air foil shaped impeller blade 20 of Fig. 7

mensional vane whereas the vaneillustrated in is illustrated in a three-dimensional view in axial perspective as being wrapped around involute curves whereby the shorter portion 53 may be attached to the impeller shroud 2| and the longer portion 54 may be attached to the impeller housing ll. of the impeller blade at the web and shroud As illustrated, the varying angles members blend together. I

Fig. 9 illustrates the impeller blade 20 of Fig. 8 wherein pins 55 interconnecting the impeller housing H and shroud 2! may be provided to secure the blade against displacement. Stub pins 55 and 51 carried by the blades 20 extend into the shroud 2| and'into the impeller housing I I to additionally anchor-the blade.

This is .a continuation-in-part of my co-pending application Serial No. 588,163, filed January a2, 1932.

I claimr i 1. A blade wheel for afluid transmission having spaced web and shroud members defining a fluid channel having fluid inlet and exit portions therebetween. fluid energizing three-dimensional blades carried by the blade wheel and having a high pitch anglesection adjacent the'web and a lower pitch angle section adjacent the shroud, the high and lower pitch angle sections convergshroud being of substantially constant pitch angle section to maintain its efficiency at the exit of the fluid channel.

2. Impeller blades having the character of a fluid foil bent into conformity with a curved center line with larger pitch angle at the W and smaller pitch angle at the shroud, the pitch angle of the blade at the shroud being substantially constant throughout and the pitch angle at the web being relieved, adjacent the discharge end of the blade to unify the flow of fluid from radially spaced points or the impeller.

3. Turbine vanes having the character of a fluid foil bent into conformity with a' curved center line with larger pitch angle at the web and smaller pitch angle at the shroud, and a small portioniof helicalform adjacent the trailing edge to reduce the fluid deflecting character;- istics of the vanes at the web adjacent the trailing edge of the vanes.

4. A blade wheel for a fluid transmission comprising spaced Web and shroud members, a plurality of spaced fluid deflecting vanes interposed between the web and shroud members and defining inlet and outlet portions, each of the vanes being contouredto embody a higher angle pitch section adjacent the web and a lower angle pitch section adjacent the shroud, the pitch angle'ot the vanes adjacent the web being relieved at.

the trailing edges of the vanes to reduce the fluid deflecting characteristics at the exit portion to unify the fluid flow and reduce-fluid turbulence.

5. In afluid transmission a fluid deflecting blade wheel having a web, spaced vanes on the web, each of the vanes embodying a high angle pitch section adjacent the weband a lower angle pitch section spaced from the web, the pitch angle of the vanes being relieved at their trailing edges to decrease the fluid deflecting characteristics of the vanes to reduce fluid turbulence.

6. A blade wheel comprising a web, vanes on the web, 'each vane having an outer edge or greater arc and higher pitch angle than the arc and pitch angle of the inner edge, and a portion of each vane being contoured adjacent the trailing edge to equalize pressure on the face ,and back of the vane adjacent the trailing edge thereof. l

7. A blade wheel comprising a web, spaced vanes on the web, each vane having an outer edge of greater are and higher pitch angle than the arc and pitch angle of its inner edge, and a trailing edge of lower pitch angle. providing an under-bend for the fluid flow whereby fluidturbulence is avoided.

8. A blade wheel comprising a web, vanes on the web, each vane having a body portion so contoured as to provide for a constant rate of energizationof the fluid, and a portion adjacent