Oct. 11, 1927. A. HALLBROWN 1,645,178,

SUPERCHARGING OF- INTERNAL COMBUSTION ENGINES Filed 001;. 25, 1926 Patented Oct. 11, 1927. 1,645,178 UNITED STATES PATENT OFF-ICE. :ABGHIBALD HALL-BROWN, 01"‘ SURREY, ENGLAND. SUPEBGEABGING _OF INTERNAL-COMBUSTION -ENGINES. Application ?led October 25, 1926,-Seria1 No. 143,951, and in Great Britain October 24, 1925.‘ This invention relates to improvements in change eed'drive for a superheater, ‘so as and connected with the supercharging of in to prov1 e high pressure and large volume . ternal combustion engines. 7 at low engine speeds and by suitable gear Broadly considered the invention consists ing to provide smaller pressure and volume’ in utilizing the suction in the induction pipe at higher engine speeds. to initiate and interrupt or to control super The invention is illustrated diagrammati charging automatically. In the preferred cally , in the accompanying drawings in form of the invention such suction is utilized which ,. to initiate supercharging when increased ex Fig. 1 is a section through a supercharger 10 ternal load has been applied to the engine, ?tted with means in accordance with the m- ' and to interrupt supercharging when the ex vention so arranged as to bring'the super ' ternal load has been reduced. charger into driving engagement with the It is known that in the normal operation engine and thus into operation when the of an internal combustion engine, which negative pressure falls in the induction pipe 70 15 draws in the fuel by suction of the piston,‘ of the engine, and to interrupt the drive to there will be-—-under normal conditions—a the supercharger when the negative pressure suction measurable in a considerable number rises in the induction pipe; of inches of water inhthe induction pipe. Fig. 2 is a diagram showing a super As the work done by the engines is increased charger vand its connection with the'induc 75 and the throttle more fully opened the nega tion pipe of an engine and ?tted with means tive pressure in the induction pipe is de in accordance ‘with the invention for ini creased until, when the engine is operating tiating and interrupting supercharging, the at maximum load, the negative’pressure in means in this instance controlling the supply the induction pipe tends to approximate to of air, while ~ 25 nil, i. e., to become equal to atmospheric Fig. 3 is a diagrammatic illustration of a pressure. ' supercharger installation in which the means For example, “with a motor vehicle driven for controlling the supercharging operation by an internal combustion, engine, when is adapted to operate gearing for driving travelling on a level road with the throttle the‘ supercharger at higher or lower speed. . 30 one quarter open, the negative pressure in In the embodiment illustrated in Fig. 1, _ the induction pipe is considerable; as the in which the supercharger and ordinary ra- ‘ engine is required to do increased work in diator fanlrunner are located on the same mounting a gradient and’ the throttle is axis, 1 denotes the supercharger, 2 the radi ‘more fully opened, the negative pressure de ator fan runner and 3 the fan driving pulley. 90 35 creases until, if gear change is not e?'ected, 4 is a‘ cylindrical recess formed in the the engine stalls‘ due to the severity of the bracket all supporting the fan spindle and5 gradient. An object of the invention in its a‘ piston movable in the c lindrical recess 4:. preferred form is to cause the supercharger Rearward of the piston t e cylinder is con3 .to be brought into action at some point be nected by a pipe 6 with the induction pipe 95 49 fore the-pressure in the induction pipe be (not shown) of the engine. The piston 5 1s comes equal to atmospheric pressure, and urged by a spring 7 designed to balance the also to provide for interruption of super pressure applied to, it‘ by the piston 5 .when I charging when the engine speed is increased, the cylinder 4 is under a negative pressure _ due to reduction of load. ' ‘ existing in the induction pipe‘ with the. en 100 The means provided for realizing the last gine running at normal ‘speed under hght named object may be used either to operate load. The piston 5 is connected with the valves, permitting the air supplied by a fan driving pulley 3, in such manner that, supercharger of any type to be delivered as the negative pressure in the lnductlon through the carburettor, or to atmosphere pipe falls due to increased load on the en 105 (in which circumstances the engine would gine, necessitating increased throttle open be working under ordinary atmospheric con ing, and the spring 7 moves‘ the piston 5 . ditions), or to bring into driving engage outwardly, the piston moves the_ driving ment with the engine a supercharger of any pulley 3 in a direction to brlng frlctlon or known type, and to interrupt'the drive at other surfaces 33 on an extension of the fan Ht 55 predetermined points, or the said‘ means may driving ‘pulley 3 into engagement w1th cor be employed to operate a double drive or responding lsurfaces on the hub 1“ of__ the 1,645,178

supercharger 1, so. as to drive the super ‘with the induction pipe, 22 the piston and charger. It will be appreciated that‘should 23 ‘the balancing spring. a the pressure in the induction pipe be again ‘In this construction the piston 22 is used increased, consequent upon decreased load to operate a change speed gear driving the 45 being applied to the engine, the piston would supercharger and so arranged that the su tend to move in the opposite direction percharger will be driven at a higher s eed against the action of the spring 7 and the when the carburettor throttle valve is ully supercharger 1 would no longer be in driv open, i. e., when the engine is working under ing relation with the fan and with the en its maximum load. I 50 ne. - . The piston 22 is connected by means of g1It is assumed in the above description that levers 24 to the sliding dog 25, which en ages the carburettor is disposed between the su the high or low ‘gear pinions 251, 252. hen percharger and the engine. the throttle valve 26 is fully open as shown In the embodiment illustrated in Fig. 2, in Fig. 3, the vacuum in the induction pipe 55 15 a suction-responsive spring~balanced piston will ‘be low and the spring 23 will move the 8 is ?tted in a cylinder 9 which is connected piston 22 forward, thus enga ing the higher _ by a pipe 10 with the induction pipe. 11 of gear and driving the superc arger at high the engine. This piston 8 is connected by speed. As the throttle valve is closed and a means of the links 12 with a two-way valve Vacuum created in the induction pipe, the 60 13 located at the junction of the atmospheric piston 22 is moved against the action of the ‘inlet and the supercharger outlet with the spring 23, thereby engaging the lower gear in’duction pipe 11, and with a pressure re and driving the supercharger at a lower lease valve 14 ?tted .to the discharge pipe of speed. - the supercharger 15. Fig. 2 shows the posi I claim : 65 25 , tion w1th the throttle valve 16 fully open and In a supercharging device for internal the supercharger delivering air to the engine. combustion engines,'an induction pipe, a su-' As the throttle valve 16 is closed, a higher percharger for deliverin air to said induc vacuum is created in the induction pi e 11 tion ' pipe, means for riving said super andghence in the cylinder 9. This higher charger, said means being automatically 70 so vacuum causes the piston 8 to move against controlled by a system com rising a cylinder the spring 17, taking. with it the links 12 having a connection to sai induction 'pipe, a which operate the two-way valve 13 and piston movable in said cylinder and a ring the pressure release valve 14, the two-way acting on said piston in the opposite irec valve 13 opening the atmospheric intake to tion to suction from said induction ipe, to 76 the induction pipe and closing the discharge cause said driving means to bring sai super from the supercharger, and also opening the charger into operation upon increase of pressure release valve 14-. ‘ , manifold pressure above a predetermined In the embodiment illustrated in Fig‘. 3 value. ' ' the numeral 18 indicates the supercharger, In testimony whereof I have signed my so 19 the induction ‘pipe, 20 the pipe connecting ' name to this speci?cation. the supercharging controlling icylinder 21 A. HALL-BROVVN.