US2434726A

US2434726A - Sudercharger for automotive vehicles

Info

Publication number: US2434726A
Application number: US510842A
Authority: US
Inventors: Stanley M Udale
Original assignee: Individual
Current assignee: Individual
Priority date: 1943-11-17
Filing date: 1943-11-17
Publication date: 1948-01-20
Anticipated expiration: 1965-01-20

Description

Jan. 20, 1948. s. M. UDALE A 2,434,726

SUPERCHARGER FOR AUTOMOTIVE VEHICLES Filed Nov. 17, 1945 Patented Jan. 20, 1948 OFFICE SUPERCHARGER FOR AUTOMOTIVE VEHICLES Stanley M. dale, Detroit, Mich., assignor to v George M. Holley and Earl Holley Application November 17, 1943, Serial No. 510,842

The object of this invention is to apply a supercharger to an internal combustion engine mounted on an automotive vehicle. The problem is to devise a supercharger that is suclently cheap so that the automotive industry can afford to buy it as an engine accessory. Such an accessory should not raise the power too much at sea levelotherwise the engine will burn up and--for example, at Denver it should enable the engine to develop maximum horsepower.

Heretofore, superchargers have been tried out and have always been found to be too expensive or they caused the engine to wear out too rapidly and the result has been that to date superchargers have not come into general use. In fact, they are hardly used at all in the automotive field.

The drawing shows diagrammatically the preferred form of my invention.

II) is the air entrance. blower. I2 is the inlet air cleaner and silencer. I3 is the choke valve. I4 is the plain tube carburetor in general use. I5 is the throttle valve. I6 is the inlet manifold. I'I is'the hot spot. I8 is the thermostatically controlledexhaust valve controlled by a thermostat I9. This valve is designed so that the flow of exhaust gas blows it into the open position. is the exhaust manifold from which the stream of exhaust gases flows against the valve I8. 2| is the exhaust outlet to a muffler (not shown).

When the exhaust controlled valve I8 moves to the position shown in broken lines, there is a bypass 22 which provides an alternative outlet for the exhaust gases. When the exhaust gases flow along this bypass 22 they strike the lmpeller of the turbine 23 which drives the blower II and supercharges the engine.

A throttle valve 24 is connected to the valve I5 so that whenever the throttle I5 is shut the valve 24 is open so that whether the engine is hot or cold the exhaust gases alway: escape through the exhaust outlet 2l when the turbine 23 is not operating.

A valve 25 operated by the diaphragm 26,

` which is subjected to the depression in the inlet manifold I6, controls a fuel passage 2l which provides additional fuel when the throttle I5 is wide open. The spring 28 is not strong enough to keep the valve 25 open whenever the throttle I5 moves out of the wide open position. The addition of this vacuum operated valve is no part of this invention and such devices have been in use for the last ten years.

The spiral thermostatic element I9 may be re- II is an impeller or 7 Claims. (Cl. 60-13) placed .by a spiral steel spring I9 made of nonthermostatic material, in which case the valve I3 will be opened only by the flow of exhaust gases impinging on the right leg which is longer than the left leg, the valve I8 being eccentrically mounted in the exhaust manifold.

In automotive practice, it is customary to mount a fan 29 driven by a pulley 30 and a belt 3|, which belt is driven by the engine. This ian blows air over the exhaust manifold and also over the thermostat I9 which is arranged to be in the path of the air blown by the fan 29. As the water in the radiator takes some time to become warm there is a definite period of time before the fan blows warm air over the thermostat I9. 'I'he thermostat I9 is located adjacent to the wall of the exhaust manifold outlet. The thermostat is thus subjected to the temperature of the air drawn through the radiator and also to the heat radiated by the exhaust manifold.

A diaphragm pump 32 operated by an engine driven eccentric 33 pumps fuel from a tank 34 through an inlet pipe 35 and an outlet pipe 36 to the float chamber 31. Check valves 38 and 39 perform the usual functions of check valves in a fuel pump. The pump diaphragm 32 is operated by a compression spring 4t! in a well known manner. A pipe 4I connects the air entrance 42 located above the venturi I4 with a chamber 43 located above the diaphragm 32. The passage 44 connects the upper part of the float chamber 31 with the air entrance to the carburetor on the atmospheric side of the choke I3.

Operation When the throttle is in the position shown and the engine has just been started, the exhaust valve 24 and the temperature responsive valve I8 are also in the positions in which they are shown. When the throttle I5 is open the temperature responsive valve I8 remainsl in the position shown if the weather is very cold. In such weather the thermostat I9 holds the temperature-responsive valve I8 in the position shown. However, when the engine warms up the ther-. mostat I9 permits the valve I8 to open under the influence of the exhaust gases flowing out of the exhaust manifold 20. When this happens, exhaust gases impinge on the turbine 23 and thc blower II rotates and supercharges the air to the engine.. When the throttle I5 is closed, the valve 24 opens and the supercharger quits.

When an engine is started cold, the lubrication is imperfect and during the warming up period the oil circulates and the walls of the cylinders become lubricated. The eneet of a supercharger is to increase the power of an engine. Therefore, the tendency oi an engine to seize or burn out increases with the power. With the thermostat it operating, the valve is is held in the position shown despite the fact that the throttle i is open and the valve 24 is closed.

Therefore, under such conditions and until the engine warms up, the exhaust gases escape through li without rotating the turbine 23. Hence it is impossible to get extra power from this supercharger setup until the engine has been run an appreciable number of minutes and the oil is free to circulate, after which time it is safe to impose upon the engine the added load due to the supercharger of the engine.

When operating at Denver it will be desirable to place the valve 2d in the closed position at all times, that is, in the position shown by the broken lines. rThe reason for this is that when operating at Denver it is desirable to have the supercharger operating all the time except, of course,

during the warming up period. The reason why it is desirable to run the supercharger all the time at Denver is that otherwise the mixture ratio becomes rich at part throttle and, of course, it is at part throttle that the mixture ratio determines mileage. f

The carburetors are designed forsea level and when they get to 'Denver the mixture becomes too rich for good mileage. When operating at sea level, however, if the supercharger runs all the time the mixture ratio would become too lean at' part throttle for the same reason. The mixture ration at wide open throttle ig alwaysfon the rich side.

in order to provide the extra fuel that is needed at wide open throttle with the supercharger operating at its maximum capacity, the restricted :fuel passage 2l would be changed so that the only departure from standard production necessitated by the addition of a supercharger is to enlarge the fuel passage @l to permit a greater amount of fuel to be taken into the engine at wide open throttle to provide fuel for the air added by the supercharger. The compression ratie would be unchanged, for the reason given. in operating a supercharged engine, it is very necessary to be sure that at maximum power the mixture ratio is sufficiently rich t prevent the exhaust valves burning. Obviously, ii maximum power is accompanied by a lean mixture, the engine will, be in the garage being serviced so much of? the time that the idea of using a super-charger will be discredited. It is therefore extremely important that the flow of fuel through the passage 2li be suiiciently great to maintain, when the throttle is wide open and the supercharger is in operation, a sufficiently rich mixture so that the engine exhaust valves, etc., will not burn out.

The element lil has two functions.

(a) it acts as a thermostat to delay the operation ci' the supercharger until the engine has warmed up.

(o) After the engine has warmed up, it acts as spring load on the valve i@ to permit exhaust gases to open the valve and to close the valve and to reiease the exhaust into the bypass 2i whenever the engine runs slowly or idles, when the exhaust gases are no longer powerful enough to open the valve.

The time interval is determined by the act that the thermostat ill responds partly to the exhaust temperature, partly to the temperature of the exhaust passing through the outlet 2li, partly the hood, which temperature is largely controlled by the temperature of the air drawn through the radiator by the fan 28, which temperature is determined by the time the engine has been running, the speed and load under which the engine has been running, and the atmospheric temperature.

When the engine is in operation, a pressure is created in the float chamber 31 through the passage which pressure is equal to the supercharger pressure. This pressure` is transmitted through the pipe 4l to the chamber 43 so that the pressure acting on the diaphragm 32 is the sum of the spring 40 plus the pressure in the air entrance l2. Hence, when the supercharger is operating the pressure of the fuel in the outlet pipe 3B increases so that the fuel will iiow into the float chamber 31 under all conditions.

What I claim is:

1. The combination with an internal combustion engine having an air entrance, a carburetor. a throttle valve therefor, an inlet manifold, a hot spot therefor, an exhaust manifold in heat conducting relationship with said hot spot, an exhaust valve located in said exhaust manifold and adapted to direct the flow of exhaustv gases against and away from said hot spot, a. relatively free outlet from said hot spot, a second outlet means responsive to the flow of exhaust gases inside said exhaust manifold adapted to move said exhaust valve so as to divert the flow of rexhaust gases away from said hot spot and said outlet to a second outlet for .said exhaust gases, a turbof supercharger adapted to be operated by said exhaust gases owlng through said second outlet, said turbo-supercharger being connected to the air inlet to said engine and adapted to supply air under pressure thereto.

2. A device as set forth in claim 1 in which a mechanically operated exhaust valve is located in said iirst exhaust outlet and in series with 'and on the downstream side of said exhaust operated valve, means interconnecting said mechanically operated exhaust valve with said carburetor throttle valve whereby these two valves are operated simultaneously and the mechanically operated exhaust valve is moved towards its open position whenever the carburetor throttle is moved towardsits closed position so as to permit the exhaust gases to escape through said ilrst outlet.

3. A device as set forth in claim 1 in which there is a temperature responsive means located outside of and adjacent to said exhaust manifold and in which the exhaust valve is also controlled by said temperature responsive means.

4. The combination with an internal combustion engine having an air entrance, a carburetor, a throttle valve therefor, an inlet manifold, a hot spot therefor, an exhaust manifold in heat conducting relationship with said hot spot, an exhaust valve located in said exhaust manifold and adapted to direct the flow of exhaust gases against and away from said hot spot, a relatively free outlet from said hot spot, a second exhaust outlet, temperature responsive means located outside of and adjacent to said exhaust manifold and adapted to control said exhaust valve so as to divert the iiow of exhaust gases from said outlet to said second outlet for said exhaust gases, a turbo-supercharger adapted to be operated by said exhaust gases flowing through said second outlet, said supercharger being connected to the air inlet to said engine.

5. A device as set forth in claim 4 in which a mechanically operated exhaust valve is located in said first exhaust outlet and in series with and onvthe downstream side of said exhaust operated valve, means interconnecting said mechanically operated exhaust valve with said carburetor throttle valve whereby these two valves are operated simultaneously and the mechanically operated exhaust valve is moved towards its open position whenever the carburetor throttle is moved towards its closed position so as to permit the exhaust gases to escape through said rst outlet.

6. In combination with an internal combustion engine having a turbo-supercharger, a carburetor and an exhaust manifold connected to said supercharger, an exhaust outlet from said manifold which permits the exhaust gases to bypass said turbo-supercharger, a spring loaded eccentrically mounted valve responsive to exhaust ow located in said exhaust manifold and adapted at low ex- 6 haust ow to divert the ilow of exhaust gases into said bypass and at high exhaust ow to direct the flow of exhaust gases into said turbine so as to drive said turbo-supercharger and to supercharge the engine.

7. A device as set forth in claim 6 in which there are means for heating the incoming air adapted to be heated by the exhaust gases diverted into said bypass.

STANLEY M. UDALE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,881,860 Muzzy Oct. 11, 1932 2,297,235 Mller Sept.I 29, 1942