US2903847A

US2903847A - Supercharger system for internal combustion engines

Info

Publication number: US2903847A
Application number: US389557A
Authority: US
Inventors: Boyd John Robert
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-11-02
Filing date: 1953-11-02
Publication date: 1959-09-15
Anticipated expiration: 1976-09-15

Description

Sept. 15, 1959 J. R. BOYD 2,903,847

SUPERCHARGER SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed Nov. 2, 1955 Air Cleaner rbo- 5U perc ho rger O 67 ln+rnol Combusiion 71 66 Engine 22 a i? L Info e manifold 2b 9 INVENTOR.

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United StatesPatent Q SUPERCHARGER SYSTEM FOR INTERNAL CONDBUSTION ENGINES John Robert Boyd, Venice, Calif.

Application November 2, 1953, Serial No. 389,557

9 Claims. (Cl. 60-13) This invention relates to superchargers for internal combustion engines and especially to superchargers of the type comprising a centrifugal compressor driven by a turbine operated by the exhaust gases from the engine being supercharged.

The prime object of the invention is to provide a supercharger of the above type which is sufficiently compact to enable same to be accommodated in the existent clearance space within the engine compartment of standard automobiles.

Another object of the invention is to provide an improved supercharger of the above type which is of simple construction to enable same to be manufactured inexpensively and installed on an automobile easily.

Another object of the invention is to provide a simplified turbo-supercharger having a single compressor wheel which will operate more efliciently than heretofore possible.

Still another object of the invention is to provide a turbo-supercharger system of the above type which in cludes simplified means whereby its effectiveness for a given engine exhaust pressure may be regulated according to the load on the engine being supercharged.

Still another object of the invention is to provide a turbo-supercharger system which will operate efficiently at low engine speeds without inducing a high engine exhaust pressure at the engine exhaust valves.

Other objects and advantages of the invention will become apparent from the following description thereof taken in connection with the drawing, in which, Fig. 1 isa side elevation view showing a turbo-supercharger installed on an internal combustion engine; Fig. 2 is an exposed elevation view, partly in outline and partly in section, showing the structural details of my novel turbosupercharger; Fig. 3 is a view, partly in outline and partly in section, taken along the lines 33 in Fig. 2 to show details of my turbo-supercharger not disclosed in Fig. 2; Fig. 4 is a side elevation view, partly in outline and partly in section, showing my manual novel supercharger as installed on an internal combustion engine and including means in the form of an ejector for assuring maximum pressure drop across the turbine portion of such supercharger at low engine speeds without inducing high mean exhaust pressure at the engine exhaust ports; and

Fig. 5 shows in schematic form the shape of the path of flow of exhaust gases through the turbine portion of my turbo-supercharger. i

Referring particularly to Fig. 2 in the drawing, according to one feature of my novel turbo-supercharger, the casing 1 containing the turbine wheel 2 is itself contained within the casing 5 for the compressor impeller 6 driven by said turbine wheel, thereby affording, as shown in Fig. 1, an extremely compact arrangement of no greater height than that of the usual intake air cleaner included on internal combustion engines, thus enabling said turbosupercharger to be interposed directly between the carburetor of said engine and the intake manifold on the 2,903,847 7 Patented Sept. 15, 1959 engine without interference with the engine hood; the usual air cleaner being suitably mounted at one side of the turbo-supercharger and carburetor assemblage and connected to the latter through the medium of the usual flexible duct tubing. i

Referring to Figs. 2 and 3, the casing 1 is provided with the usual cylindrical chamber 7 in which is disposed the turbine wheel 2; said wheel having a plurality of the usual circumferentially spaced-apart blades 8 integrally attached to the usual disk-shaped rotary hub 9 and projecting from said hub in an axial direction for slight clearance between same and the peripheral Wall 11) of said chamber. The casing 1 is further provided with an inlet or nozzle 11 opening into the wall 10 to allow for admittance of engine exhaust gases into chamher 7 via the blades 8 of the turbine wheel; an outlet opening 12 through said wall being provided in casing 1 to allow for exit of the engine exhaust gases from chamber 7 via passage through the turbine wheel blades 3 a second time.

Referring particularly to Fig. 3, the inner turbine casing 1 is joined with the outer compressor casing 5 in the region of the turbine inlet and

outlet openings

11 and 12, otherwise the two

casings

1 and 5 are separated one from the other to provide a segmental annular clearance space 15 for permitting flow of fluid under pressure there-past.

Referring now particularly to Fig. 2, as shown in the drawing, the upper end of the casing 5 serves as an inlet to the compressor impeller 6 and is adapted for registry with the outlet 16 of the carburetor which is to be mounted directly thereon. The impeller 6 disposed within the upper portion of the casing 5 comprises the usual blades 17 which operate in cooperation with said casing portion to withdraw the carbureted mixture of air and fuel from the carburetor and discharge same via the clearance 15 and the lower portion of casing 5 into the intake manifold of the engine by way of registering openings 20 and =21 in such portion and manifold, respectively. Spaced-apart diffuser vanes 18 extending between

casings

1 and 5 are disposed in the segmental clearance spaces 15 to properly direct such discharge from the impeller wheel 6.

According to the feature of compactness of my novel turbo-charger, the blades 17 of the impeller 6 are disposed about the outer periphery of a tapered central hub portion 19 having its apex disposed at the inlet to the upper portion of casing 5 and its base portion in proximity of and in coincidence with an end Wall 26 of the turbine casing 1; such hub portion thereby acting as a diffuser directing flow from said inlet to the clearance spaces 15 during operation of the impeller. The blades 17 are spaced-apart circumferentially of the hub 19 to which they are suitably attached and extend in an axial direction from the apex of said hub to the base portion in alignment with the bottom face thereof. The inner peripheral surface of the upper portion of casing 5 follows, in general, the contour of the hub 19 of the impeller, and the outer edges of the blades 17 of said impeller follow the contour of said inner surface and are in close proximity thereto.

For sake of illustration, the impeller 6 of the compressor portion of the turbo-supercharger may be operably connected to the turbine wheel 2 of the turbine por tion through the medium of such as a shaft 22 suitably journaled at the inlet end of the compressor as by means of a journal 23 supported by a spider 24- in said inlet and at the opposite end by means of a journal 25 suitably mounted in the respective end wall 26 of the turbine casing 1.

Referring to Figs. 2 and 3, according to another feature of the invention, the turbine portion of my novel turbosupercharger is provided with an element 30 disposed within chamber 7 and within the circular area therein defined by the inner peripheral edges of the blades 8 of the turbine wheel 2. The upper peripheral surface of element 30 defines the inner contour of the area available for flow of exhaust gases from the engine through the turbine, and which element 30 may be made adjustable to' different angular positions relative to the turbine inlet nozzle 11, as indicated in Fig. 3 by the dash outlines, to regulate admittance of exhaust gas from the engine via inlet nozzle 11 to and through the turbine. Element 30, as viewed in Fig. 2, is of sufficient thickness as will substantially fill the axial space between the hub portion 9 of the turbine wheel 2 at the upper side of said element 30 and the end wall 31 of turbine casing 1 at the lower side of said element, thereby to assure that the engine exhaust gases admitted via nozzle 11 to the chamber 7 will not by-pass the element, 30 en route to turbine outlet 12. The profile of element 30 radialwise of a shaft 33 on which it is mounted, is in the form of a modified elipse having a round bottom surface 34 corresponding to the curvature of; the inner peripheral surface of the turbine blades 8 and formed on a radius of curvature centering at the axis of shaft 33 so as not to interfere with the movement of the turbine blades 8 about said surface 34 regardless of the angular position of element 30 relative to shaft 33. The surface 34 of control element 30 merges with a gently rounded surface 35 at the upper side of said control element 30, as viewed in the drawing, via a rouuded surface of a portion 36 of element 30 projectiug from the shaft 33 at one side in the direction of the inlet nozzle 11, and with said surface 35 on the opposite side of said shaft 33, by way of a rounded surface of a portion 37 extending from said shaft in the direction of the outlet opening 12. The surface 35 of element 30 defines the inner peripheral surface for the direction of flow of engine exhaust gases through he c n Referring to Figs. 3 and 5, according to a feature of my invention, by virtue of the disposition, arrangement and configuration of the inlet nozzle 11, element 30, and outlet 12 relative to the turbine wheel 2, the engine exhaust gases admitted to the turbine are conducted en route to outlet 12 first through a convergent conduit the form of the inlet nozzle 11, then through a divergent-convergent conduit defined by the inner surface of casing 1 and the surface 35 of element 30 in which substantially more than half of the turbine wheel 2 disposed. By virtue of the convergent, divergent, convergent flow path above, the exhaust gases passing through the turbine can be made to attain a substantially constant. supersonic velocity in the divergent-convergent region, in which the turbine wheel is disposed, at substantially all turbine inlet, or engine exhaust, pressures for any given position of element 30. The divergentconvergent region extends along a curvilinear path between inlet and outlet of the turbine to direct the high velocity gases along a circumferential path, a path in the direction in which the turbine wheel 2 rotates, to extract from such high velocity gases a maximum amount of work in the form of rotation of such wheel at high velocity.

According to another feature of the invention, the

portion 36 of element 30 projecting in the direction of inlet nozzle 11 from one side of the shaft 33 may be made longer than the portion 37 of element 30 projecting in the direction of outlet 12 from the opposite side of shaft 33, and the latter portion 37 'may be made more blunt with respect to portion 36 for reasons which hereinafter will become apparent.

The inlet nozzle 11 is so disposed in the casing of the turbine as to open to the interior thereof substantially tangentially of the turbine wheel 2. and in efiective alignment with the blades 8, while being so disposed relative to the control element 30 that angular movement of said element 30 to such as the position indicated by the dash line 40 will advance portion 36 of said element 30 to a position in which flow of engine exhaust gases from nozzle 11 to the divergent-convergent region in interior of the casing 1 by way of the blades 8 of the turbine wheel will be more restricted than otherwise attained in the position of portion 36 in which it is shown in the drawing in solid outline, and less restricted when the portion 36 of element 30 is caused to assume the position in which it is shown in dash outline 41 in the drawing. The outlet opening 12 is so adapted and arranged relative to the turbine wheel 2 as to allow for facile egress of exhaust gases from the turbine, and so disposed relative to the portion 37 of the control element 30 that such facile egress will be relatively unaffected by movement of such portion 37 to the different angular positions of the element 30 as aforedescribed.

The shaft 33 to which the control element 30 is attached may be suitably journaled in an accommodating opening provided in the end wall 31 of casing 1, and may be adapted for rotary movement to cause the element 30 to assume its different angular positions through the medium of such as a worm driven gear arrangement 45 contained within a suitable housing 46 attached to the casing 1 of the turbine and disposed within the lower portion of the compressor casing 5; the gear portion of the worm and gear drive being attached to the shaft 33 and the worm portion extending outwardly to the exterior of the supercharger by way of a suitable opening (not shown).

According to another feature of the invention, the modification as shown in Fig. 4 includes an ejector nozzle 60 suitably housed and arranged to receive exhaust gases from the engine in by-pass of the turbine portion of the turbo-supercharger to cause a suction to be generated at the outlet 12 of the turbine portion of the supercharger by virtue of flow of engine exhaust gases through such ejector. The turbine inlet nozzle 11 of the turbo-supercharger may receive engine exhaust gases or exhaust gases from the engine by way of a fluid conyeying meanssuch as a manifold 64 and a branch of said manifold 64. may form the inlet to the ejector nozzle 60. A manifold 65 may serve as the connection from the outlet 12 of the turbine portion of the supercharger to the usual ejector housing 61 encircling the outlet of the ejector nozzle 60 suitably arranged relative to a reduced section 66; of an ejector diffuser section 67 as to cause the aforementioned suction at the turbine outlet by virtue of flow of engine exhaust gases through the ejector nozzle 60 according to well-known principles of fluid flow.

For the purposes of controlling the effectiveness of the ejector nozzle 60, as shown in Fig. 4, such as a conical-shaped, element 70 may be provided for graduated movement into, and out of the outlet end of the ejector nozzle to control or regulate flow of engine exhaust gases therethrough. The element 70 may be attached to the usual linkage 71 suitably arranged for actuation from a station exterior of the housing 61 containing the ejector no le Operation Assume that the internal combustion engine with whichmy. novel turbo-supercharger system is associated is operating at a, normal load and speed; that the control element 30; of the turbine portion of my turbo-supercharger is in theposition in which it is shown in solid outline in Fig. 3 of the drawing; and that the element 70 associated with the ejector nozzle shown in Fig. 4 is in a position relative to the outlet end of the ejector nozzle 60 to close or partially close same. Under the assumed conditions, referring to the various figures of the drawing, the exhaust gases from the engine will flow byway of a branch of the manifold 64 into the inlet nozzle 11 of the turbine portion of the turbo-supercharger and to the blades 8 of the turbine wheel through which such gases will expand for the first time interior of the casing 1 to attain super-sonic velocity in the divergent-convergent region, and thence pass through said blades for the second time to the manifold 65 via outlet 12.

Such passage of engine exhaust gases through the turbine wheel 2 will occur at a normal rate commensurate with the normal load conditions of the engine and as determined by the normal position of the control element 30 and will cause said turbine wheel to rotate at a particular speed and in turn to drive the compressor impeller 6 at a rate also commensurate with the load and speed conditions of the engine to cause combustion air for the engine to be drawn in by way of the air cleaner into the carburetor, where same is mixed in the usual fashion with fuel, to pass through said carburetor, through the blades 17 of the impeller 6 within casing 5 and around the casing 1 of the turbine by way of the clearance space and guide vanes 18, into and through the lower portion of the casing 5 of the compressor, into and through the registering

openings

20 and 21 of the casing 5 and engine intake manifold, respectively, for distribution in the usual fashion to the various cylinders of the engine to maintain operation of same in an eflEicient manner and at the assumed normal load and speed conditions thereof.

Referring to Fig. 4, at the same time, a portion of the gases being exhausted from the engine will flow by way of the respective branch of the manifold 64, in by-pass of the exhaust gases passing through the turbine, to the ejector nozzle 60 where same will cause a suction to be generated in the manifold 65 in aid of withdrawal and passage of exhaust gas through the turbine via the exhaust opening 12 and eventual dispensation of such gases to the atmosphere by way of the ejector diffuser manifold 67 and such as the usual muffler and exhaust pipe (not shown) associated with an internal combustion engine. The efiect of the ejector nozzle on the turbosupercharger will be such as to increase its efiectiveness by encouraging the passage of exhaust gases through the turbine without increasing the back pressure at the engine exhaust. The effectiveness of the ejector nozzle 60 under normal load and speed conditions of the engine may more or less be arbitrarily determined according to selective positioning of the control element 70.

Assume now, for the sake of illustration, that the internal combustion engine is being employed in such as an automobile and that same is coasting down hill, in which case the load on the engine will be nil, while the engine will be turning over at average speed. Under such circumstances, it is desired to render the turbo-supercharger less effective in order that the amount of air drawn into the carburetor will not cause an exceptional amount of fuel to be admitted to the engine which cannot be utilized under the assumed no-load condition. According to a feature of the invention, the control element 30 associated with the turbine will be caused to assume some position such as the position in which it is shown in the dash outline 40 in Fig. 3 by adjustment in position of the shaft 33 through the medium of the worm and gear arrangement 45. By virtue of such movement of the control element 30 toward or to its position 40, flow of exhaust gases from the respective branch of the manifold 64 will be relatively more restricted than in the normal position of said element 30 and the mass flow of such gases through the turbine will be reduced, with the result that the speed of the turbine wheel 2 will be correspondingly reduced as well as will be the speed of the compressor impeller 6 driven by said turbine wheel so that less air will pass through the carburetor and fuel consumption will be reduced. At the same time, a greater portion of the exhaust gases from the engine will pass via respective branch of the manifold 64 through the used to advantage.

6 ejector nozzle 60 to the atmosphere by way of the ejector diffuser manifold 67. It will be understood that with the reduced admission of fuel to the engine as a consequence of the throttle position and the reduced effectiveness of the turbo-supercharger, the pressure and effectiveness of any exhaust gases leaving the engine will be greatly reduced so that flow through nozzle 60 will not materially affect the effectiveness of the turbine.

Assume now that the engine is operating at an increased load and/ or speed, such as would correspond with travel of an automobile on the level at high speeds or at average speeds going up grade. Under such circumstances, it will be desired to increase the effectiveness of the turbosupercharger and the control element 30 will be caused to assume the position in which it is shown in the dash outline 41 in Fig. 3 and in which position its portion 36 is retracted further away from the outlet of the inlet nozzle 11 to allow for facile admittance of engine exhaust gases through the turbine, which in turn will result in an increased flow of such gases therethrough and a consequent increase in speed of the turbine wheel 2 and hence of the compressor impeller 6, as well as an increase in the volume of air admitted from the atmosphere to the engine intake manifold by way of the carburetor of my novel turbo-supercharger to cause the engine to more completely burn the fuel mixed with such air and therefore generate increased power commensurate with the assumed load and/or speed conditions of the automobile employing such system. Under such operating conditions of my turbo-supercharger, the adjusting element 70 associated with the ejector nozzle 60 may arbitrarily be positioned relative to the output of said nozzle 60 to render same more or less effective to assist operation of the turbine according to desires.

Assume now that the engine is operating at low speed under average or high load conditions. Under such assumed conditions, it will be desired to render the turbine portion of my turbo-supercharger maximally efiective by movement of the control element 30 to the position indicated by the dash line 41 to allow for facile admission of exhaust gases through the turbine by way of the respective branch of the exhaust manifold 64, while at the same time it is desired that the back pressure imposed by flow of such exhaust gases through the turbine will not impose an undue restraint at the engine exhaust ports which will act on the engine in opposition to the effect of supercharging same. Under these conditions, the ejector nozzle 60 shown in Fig. 4, will be The control element 70 will be moved to an open position to allow for maximum bypass flow of exhaust gases through the ejector which flow will create a minimal amount of back pressure on the engine exhaust ports while at the same time greatly increase the effectiveness of the exhaust gases passing through the turbo-supercharger by virtue of increasing the diflerential in pressure between the input and output side of the turbine portion of said turbo-supercharger and thereby increase the work available from said gases and realized by said turbo-supercharger in the form of an increased output.

Having now described the invention, what I claim as new and desire to secure by Letter Patent is:

1. In combination: an internal combustion engine having an air-fuel intake manifold and an exhaust gas manifold; a turbo-supercharger having an inlet and outlet communicating with said exhaust gas manifold; said turbo-supercharger defining between said inlet and outlet a relatively convergent, divergent and convergent flow path for exhaust gas passing therethrough; and, a camlike control element mounted within said turbo-supercharger for changing the area and curvature of said flow path.

2. In combination: a fluid conduit connected to a variable source of fluid under pressure, said fluid conduit dividing at a first junction point into a first fluid passage a and'a second fluid passage downstream of said source, said first fluid passage and said second fluid passage being joined together to re-establish said fluid conduit at a second junction point further downstream from said source; a turbine having an inlet and outlet communicating with said first fluid passage, said turbine defining between said inlet and outlet a relatively convergent, divergent, and convergent flow path for fluid passing therethrough; a cam-like control element within said turbine for changing the area and curvature of said flow path; and, ejector nozzle means embodied in said second fluid passage at said second junction point, said ejector nozzle means acting to create a pressure differential urging flow through said first fluid passage towards said second junction point.

3. The combination of: an internal combustion engine having a carburetor, an air-fuel intake manifold and an exhaust manifold; a turbo-supercharger associated with said engine, said turbo-supercharger comprising a hollow casing containing both air compressing means and turbine means; said turbo-supercharger having an air-fuel inlet for pressure sealed mounting on an outlet end of said carburetor and an air-fuel outlet for pressure sealed mounting on an air-fuel inlet portion of said air-fuel intake manifold, a portion of said exhaust manifold I being divided at a first given junction point to form a first fluid passage and a second fluid passage, said first fluid passage and said second fluid passage being joined together at a second given junction point downstream of said first given junction point to re-establish said exhaust manifold, said turbo-supercharger being interposed in and having an inlet and outlet communicating with said first fluid passage whereby said turbine means is driven by gas flowing through said first fluid passage, said turbo-supercharger defining between said inlet and said outlet a relatively convergent, divergent, and convergent flow path for exhaust gas passing therethrough; and, a cam-like control element within said casing for changing the area and curvature of said flow path.

4. The combination according to claim 3, and ejector nozzle means embodied in said second fluid passage at said second junction point, said ejector nozzle means acting to create a pressure differential urging flow through said first fluid passage towards said second junction point.

5. The combination according to claim 4, and adjustable means for varying the effective area of said ejector nozzle means relative to a given quantity and pressure of exhaust gas admitted thereto through said second fluid passage.

6. In combination: a fluid conduit connected to a variable source of fluid under pressure, said fluid conduit dividing at a first junction point into a first fluid passage and a second fluid passage downstream of said source, said first fluid passage and said second fluid passage being joined together to re-establish said fluid conduit at a second junction point further downstream from said source; a turbine having an inlet and outlet communicating with said first fluid passage, said turbine defining between said inlet and outlet a relatively convergent, divergent, and convergent flow path for fluid passing therethrough; a cam-like control element within said turbine for changing the area and curvature of said flow path;

and, ejector nozzle means embodied in said second fluid passage at said second junction point, said ejector nozzle means acting to. create a pressure difierential urging flow through said first fluid passage towards said second junction point.'

7. The combination of: an internal combustion engine having a carburetor, an air-fuel intake manifold and an exhaust manifold; a turbo-supercharger associated with said engine, said turbo-supercharger comprising a hollow casing containing both air compressing means. and turbine means; said turbo-supercharger having an air-fuel inlet for pressure sealed mounting on an outlet end of said carburetor and an air-fuel outlet for pressure seal mounting on an air-fuel inlet portion of said air-fuel intake manifold, a portion of said exhaust manifold being divided at a first given junction point to form a first fluid passage and a second fluid passage, said first fluid passage and said second fluid passage being joined together at a second given junction point downstream of said first given junction point to re-establish said exhaust manifold, said turbo-supercharger being interposed in and having an inlet and outlet communicating with said first fluid passage whereby said turbine means is driven by gas flowing through said first fluid passage, said turbosupercharger defining between said inlet and said outlet a relatively convergent, divergent, and convergent flow path for exhausting gas passing therethrough; and, a camlike control element within said casing for changing the area and curvature of said flow path.

8. The combination according to claim 7, and ejector nozzle means embodied in said second fluid passage at said second junction point, said ejector nozzle means acting to create a pressure differential urging flow through said first fluid passage towards said second junction point.

9. The combination according to claim 8, and adjust,- able means for varying the effective area of said ejector nozzle means relative to a given quantity and pressure of exhaust gas admitted thereto through said second fluid passage.

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