US2575384A - Throttle control for motor vehicle engines - Google Patents

Description

Nov. 20, 1951 HORTON 2,575,384

THROTTLE CONTROL FOR MOTOR VEHICLE ENGINES Filed July 1, 1949 'INVENTOR.

[ma/)2 C. Max:012

BY M, @244.

ATTORN EYS.

Patented Nov. 20, 1951 THROTTLE CONTROL FOR MOTOR VEHICLE ENGINES Erwin C. Horton, Hamburg, N. Y., assignor to Trico Products Corporation, Buffalo, N. Y.

Application July 1, 1949, Serial No. 102,597

' 2 Claims.

1. This invention relates to motor vehicle engines of the internal combustion type which utilizes the well known carburetor for providing the desired combustible mixture. Such mixture passes through the intake manifold to the combustion chambers, its passage being controlled by a butterfiy valve disposed in the manifold and, often referred to as the engine throttle.

For engine idling, the throttle is set or given a definite adjustment called its closed position and to which position it returns when releasing the accelerator pedal or otherwise fully throttling the engine. While this idling'position of the throttle is correct and proper for normal operation, yet under certain conditions a different adjustment should be made to avoid the stalling of the engine. Thus, when starting 'a cold engine, or when braking the vehicle and through the inertia. of the fuel in the carburetor, or otherwise, a sudden enrichment of the combustible mixture is caused sufficient to stall the engine, if the throttle is opened a slight degree, or in other words the idlgine acceleration, the starting of the cold engine will be facilitated and the stalling of the idling engine will be avoided.

The present invention has for its object to i provide a control for motor vehicle engines which will automatically prevent the decelerating of a dying engine by immediately opening the intake passage as the engine requires it and thereafter retarding the closing action toinsure the engine acceleration over a definite period.

This invention also has for its object the automatic adjustment of the extent of the opening past the throttle valve in accordance with the value of the suction or low pressure conditions in the intake manifold whereby the throttle valve is given at all times the extent of opening necessary to insure an adequate amount of the explosive mixture of the engine to maintain operation thereof and to compensate for variations in-v the pressure condition pertaining in the intake manifold.

Further the invention has for its object to provide a motor vehicle engine which will be free from stalling and one which will quickly start upon the initial turning over of the engine.

In the drawings:

Fig. 1 is a fragmentary elevation of a motor vehicle internal combustion engine embodying the present invention; and

Fig. 2 is a sectional view of one embodiment of the automatic throttle control of the invention herein.

1 to proceed.

2 Referring more particularly to the accompanying drawings the numeral l designates the internal combustion engine of a motor vehicle, having an intake manifold 2 with a throttle valve 3, the

.idling position of which is determined by the adclosed for proper vehicular manipulation and travel. These parts are herein shown as illustrative only, no emphasis being placed on the structural features of these well known parts.

While the manually set idling position of the throttle, as determined by the stop 4, is proper for a portion of the vehicular and engine operations, still, there are times and conditions as previously mentioned, when it is desired to advance or open the throttle slightly beyond the normal idling set. It is known that during the life of a motor vehicle engine that the initial set of the throttle valve becomes changed due to vibration and wear of parts and also that the initial idling throttle position becomes ineifec tive :or inadequate to maintain the feed of a suflicient amount of fuel to the engine to maintain it in operation due, among other things, to wear of the piston rings and cylinder, to an accumulation, of carbon deposits in the cylinders, resulting in a less efiicient vacuum condition in the intake manifold, thus resulting in the drawing of a smaller volume of the explosive mixture pastthe throttle valve in its initial adjustment for idling operation of the engine. Frequently, the engine willstall when bringing the vehicle to rest at a trafic signal, and if the driver is not alert or acquainted with the fact that his engine has died hewill delay the trafiic when the signals change while the vehicle is traveling at a faster speed. Consequently, when the vehicle is braked or the momentum is checked so as to cause a sudden enrichment of the combustible mixture, not infrequently due to the inertia of the liquid fuel in the system, the engine will stall. Such stalling might be avoided if the motorist would tramp his throttle in time to open the intake manifold. Also if the stop 4 was advanced a little such stalling might be avoided, but such advancing of the stop would cause the engine to race unnecessarily at normal idling.

Further, with the advent of the free wheeling, the engine is permitted to idle I In accordance with the present invention means are provided to automatically increase the volumetric intake of the combustible mixture by the engine, to automatically advance the throttle, or open the same, so as to slightly accelerate the engine; and to prolong the period of open throttle state sufficiently to insure the desired engine accelerationt Thus, a'chamber9, having communicationwitl'f interval during which the throttle remains partway open so as to give the engine a longer period of acceleration and thereby insure the maintenance of proper engine idling operation. Dur- 5 ing the retarded return movement, when the ball valve 22 is seated, there will be a predetermined air leakage about the periphery of the piston.

1ft operation; if the engine is at rest the spring l2willbeaotingthrougli the movable wall and the intake manifold at the engine side of thBJOits-Stiim 13 to hold the throttle in its advance throttle, as by a conduit III, has a movable. wall which is resiliently urged in one directionwf: movement and adapted to be moved in the oii posite direction by suction or a partial vacuum in the chamber. If the movablejwall, herein depicted as a diaphragm, is not inherently resilient, a spring l2 may be provided for producingithe-= resilient urge, such urge being utilized for moving the throttle to its advance setting to thereby accelerate the engine bath to he normal idling,

which isdetermined by the stop 4. Thespring I2 is prefer'ablydisposedwith'in-the chamberj the same acting to advance-the throttle? The"'cham ber may be conveniently" arranged with respect to -themanifold or carburetor; and -its movable" wall i l "may'b'e'connected' 'to'th'e throttle"'as"-by means of arod "or stem-i3. Becausea pl'ay connection is desired the rod has a shoulder It upon whichan arm ofthe bell-crank 5"rests-=soidling position. Thus, the throttle will be opened a certair'i de'gfee'lsufficient to facilitate the starting of' the engine. Immediately upon starting and the -formation of a vacuous condition in the isuntareimamroidme movable wall will be moved away fr'om'the throttle and the latter will be returned to itsnormal throttling position as retarded bythe dashpot, such return being efiected by'm'eans of the usual throttle spring 25. Should the cold engine begin to" die or slow down sunlpendntly of 'the movable wall I l. The movement of the wall under 'the action of the-spring l2; and consequently theextent of advance given the throttleymay bevaiiedby-anadj unable-stew dashpot means acting to retard the'closingbf the valve following its operation by" said second meansi I v 2. Engine flier intake" means; a" carburetor" II:- This stop *is hei'eindepictd inthe formof *th'rott1e=-- valve-1 pressure" differential operateda sleevethreaded *in a I spideror bracket- I 5 and serves to guide the *stem i 3 in its reciprocations.

Themovement of" the Wall--l l "in responseto' the manifold suction; maybe governed-byadjustablemeans controlled" by the diifrence' irr pressure' betweenthe interiorand exteriorbf the 'fuel. in= takemeans for opening th'e throttle valve iftlie engine' tendsto' stall while idling; said pressure tensioningmeans for thespring l2: Thusfby'a-d 40""difierentialoperated means comprising" mechajusting the screwi 6 "-inor "out,--thecup 1 E oarried 1; thereby and supporting the lower end of the" spring will correspondingly increase: ordeer-ease the spring -'ten'sion so that-the movable v'rall-Will' respond to moreorless-manifold-suction As the engine beg-ins '-todie, the manifold suc tion will decrease andwhen" the automatic throttling auxiliary or" accelerator functionsthrough the spring=acti0n of thew-all l toopenthe intakepassage the engine-becomes slightly accelerated and restored to the idling' speedf To in'sure this acceleration a'dashpot- I 8 is provided to retard the response of J the wall I I to the restored idling suctione The dashpot illustrated,

byway 'ofexample; comprises a chamber Wandapiston 21); the latter being connected to thestem .1 3 by an integral extension 2] of-thelatter; Acne-way check valve 22 ir'eelyopens a tra nsfer port-23against the urgeof aspring fl when thespring 12 functions but closes u-pori reverse-ineve=- ment of thepiston 20 th retard the 'rnovement of wall ll when-the -idlingsuctionis -restored by. the engine acceleration.- This prolongs the nism-"ior moving thethrottlewalveto a" partially open positionsaidmovem'entactingindependent 1y of the conventional thrott1'e""- opening means" and intake suction' responsive means i for over= 45" coming said mechanism and a daslipot device" mechanically connected to the'suction responsive niean's'f for delaying its operatiom and actin therethrou'gh -toretard theclosingof the throttlevalvei ERWIN'C; HORTON;

REFERENCES I CITED flhe following"references"are of "record in the" fileof this "patent? UNITED STATES 1 PATENTS

Images