US2397392A - Heat transfer resisting means for carburetors - Google Patents

Description

March 26, 1946. w, WEBER I 2,397,392

HEAT .TRANSFER RESISTING MEANS FOR CARBURETORS Fi led Jan. 24, 1944 INVENTOR.

Jvlv ATTORNEY Patented Mar. 26, 1946 UNITED STATES PATENT F FICE HEAT TRANSFER'RESISTING' MEANS FOR CARBURETQRS Walt'enH. Weber, Detroit, Michl assi'gnori tmDetroit -'Lubricator: Company; Detroit, Mich,

\ corporation.- of -Michiganv Application January 24, 1944', Seriai'No." 5193115 3 Claims.

This. invention relates to new andlusefuli improvements. in carburetors for supplying; fuel to an internal combustion engine.

In the operation of carburetors usinggasoline or other radially vaporizabl'e fuels, it may occur that the heat of the engine conducted to the carburetor float chamber will causethe fuel therein to boil,,and thus upset the. uniformrate. of supply of fuel to the mixing chamber. In some cases, this will even cause a vapor lock preventing operation of the engine. It is, accordingly, the object of this invention to providelmeansto reducethe rate of. heat transfer from the engine. to thecarburetor fuel container or reservoirsufficiently so that vapor locking andboiling. will not occur.

The invention consists i'ntheimproved. construction and combination of parts. to be more fully described hereinafter and. the novelty of which will be particularly pointed out. anddiS- tinctly claimed.

In the accompanying drawing, to be taken. as. a part of this specification, there is fully and. clearly illustrated a preferred embodimentbi theinvention, in which drawing:

. Figure 1 is a view in vertical central section of a carburetor attached to an engine and having the heat transfer blocking means of the invention;

Fig. 2 is a plan view of the outlet end portion of the carburetor;

Fig. 3 is a view in side elevation of the outlet end portion of the carburetor, and

Fig. 4 is a view in section of the outlet end portion of the carburetor, taken on the line 4-4 oi Fig. 2.

Referring to the drawing by characters of reference, l designates generally the body member of a carburetor having a mixture passageway 2 with an air inlet 3 and an outlet 4. The member I is preferably a die casting having integrally cast therewith a constant level fuel reservoir 5 which, by reason of its rigid connection to the body member I, is in intimate heat exchange relation therewith. The reservoir 5 has the usual liquid inlet 6 for liquid fuel, such as gasoline. The liquid level in the reservoir 5 is controlled by a float member 1 which is operatively connected to a valve 8 controlling flow into the reservoir 5 from the inlet 6. The reservoir 5 is connected to the mixture passageway 2 by a fuel conduit 9 having a calibrated inlet port I0 below the reservoir liquid level. The conduit 9 has a portion H above the reservoir liquid level and has an outlet or nozzle l2 discharging into the passageway 2 within the throat of a Venturi tube l3 positioned within the passageway 2. The usual butterfly type throttle valve lllisprovided; to control the discharge of fuel mixture. from" the carburetor outlet 4.

The outlet end, portion ofthe' passageway 2 is ,f-ormedjby a thin wall'tubul'ar conduit member 15 of. low heat, conducting'material, such for example .as stainless steel". The member l5 'flt'swithin an internalv annular. end recess in the body membar I, and. has its inner endedge abutting. ashoulder, to. limit its inward. movement; The conduit member I5 extend beyond or projects externally from the body'member l and has its exterior end provided, an out-turned lateral flange Hi. The

.body, member I may, beprovidedwith legs or fins ll which, extend longitudinally of the exterior portion of the memberl5 and back Or reinforce the. flange. l6. Surrounding the member l5 and projecting laterally, from the outlet end portion block. l9 bya peripheral wall 2| which, together with; the plate, memb'er20}. provides an inverted I cup like member having its rim, i. e. the edge of the wall 2| seating on the block I9. Through the plate member20 there are air outlet apertures 22 for discharge of air from the interior of the hollow flange. The wall 2! is provided with a plurality of apertures or slot openings 23 for the inflow of air to the interior of the 'hollow flange. The openings or apertures 22 and 23 cooperate to provide for cooling air flow through the hollow flange and in heat abstracting relation to the exterior surface of the projecting portion ofthe conduit member I5. The plate member 20 also has openings 24 therethrough positioned adjacent the flange wall l8 and in which are positioned bushings 25 of a length to extend flush with the flange I6 and also flush with, or slightly beyond, the rim of the Wall 2|. The bushings 25 are also each preferably provided with anend flange 26 which seats against and is backed by portions of the wall 2!. The bushings 25 are preferably of low heat conducting material, such as stainless steel, and receive bolts or studs 21 which serve to clamp and secure the carburetor to the block l9.

It will be apparent from the foregoing description that the reservoir 5 is protected against the conduction of engine heat through the walls of the body member I. Not only does the heat flow resisting member 15 cut down the rate of heat conduction from the block l9, but in addition this member I5 is cooled by air flow entering the hollow flange through the openings 23 and discharging through the openings 22. This air flow, I

, 1. In a carburetor, a body member to 'be secured to an engine and having a mixturepassageway with an outlet for supplying a combustible mixture to the engine, a liquid fuel reservoir carried an engine engaging edge, said flange Wall member surrounding and being spaced from said con-v duit member and extending from the outer marginal edge of said plate member and terminating in an engine engagin edge such that said wall member, said plate member and said conduit 7 member provide a channel surroundin said conby and in heat exchange relation with said body member, a tubular thin wall conduit member of member and forming the outlet portion of said passageway, a hollow flange extending from said low heat conductivity extending from said body body member and surrounding said conduit member, said flange comprising an apertured lateral a carried by said passageway portion and communiplate member and a peripheral apertured wall member spaced laterally from and surroundin said conduit member and for abutting ehgagement with the engine to support said body member on the engine, the'apertures in said apertured members providing inlets and outlets forair flow in cooling. relation to the exterior of said conduit member, said plate member Lhaving'bolt receiving openings adjacent said wall member, a bushing jmember in each opening and having a flange seatin again'stsaid wall member, said conduit member having a flange in the plane of said bushing member flanges, and reinforcing means extending from said plate member and backing said conduit member flange.

2. In a carburetor, a body member having a passageway portion with a mixture passageway and the outlet end of said passageway portion, and a thin wall conduit member of relatively low heat conductivity fitting within said passageway and projecting from the outlet end of said passageway portion and beyond said plate member, said conduit member having its outlet end'terminating in duitfmem'ben'said plate inemberf and said wall member each-having apertures therethrough for flow, of cooling air through said channel to abistract heat from said flange and conduit member so as to resist conduction of engine heat to said reservoir. 7

3. In a carburetor, a body member having a passageway portion with armixture passageway and having ahollow flange for connection of the body member to an engine, a liquid fuel reservoir 'catively connected to said passageway, said flange including a lateral plate member and a peripheral wallmember, said plate member extendin around the outlet end'of said passageway portion, a thin wall conduit member of relatively low heat conductivity fitting within said passageway and projecting from the outlet endof saidppassageway portion and beyond said plate member, said conduit member having its outlet end terminating in an annular surrounding flange for engagement with the engine, said flange wall member sur- 'member and projecting from said flange plate member into abutting engagement With said conduit member flange,

WALTER I-I. WEBER.

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