US3769954A

US3769954A - Heat deflector shield for fuel metering device or the like

Info

Publication number: US3769954A
Application number: US00270207A
Authority: US
Inventors: H Morgenroth
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-07-10
Filing date: 1972-07-10
Publication date: 1973-11-06
Anticipated expiration: 1990-11-06

Abstract

A generally cup-shaped resilient heat deflector shield is secured to an engine and related carburetor; the shield has at least two positions one of which deflects the flow of hot air away from the carburetor while a second position, determined by the resilient deformation of the shield, enables ready excess to externally accessible adjustment means carried by the carburetor.

Description

I United States Patent 1 [111 3,769,954 Morgenroth Nov.r6, 1973 [54] HEAT DEFLECTOR SHIELD FOR FUEL 1,283,302 10/1918 Reid 123/195 A METERING DEVICE OR THE LIKE 1,761,221 6/1930 Marx 123/142 3,612,022 10/1971 Von Bombard et al..... 123/198 E X [76] lnventor: Henri Morgenroth, 3090 Hidden Valley Ln., Santa Barbara, Calif. 93108 [22] Filed: July 10, 1972 [21] Appl. No.: 270,207

[52] 1.1.8. Cl. 123/198 E, 261/1, 261/65, 123/142 [51] Int. Cl. F02m 15/06, F02rn 17/30 [58] Field of Search 123/142, 195 C, 198 A, 123/198 E; 261/1, 65

[56] References Cited UNlTED STATES PATENTS 930,596 8/1909 Hanks 123/142 UX Primary ExaminerAl Lawrence Smith Attorney-Walter Potoroka, Sr.

[57] ABSTRACT A generally cup-shaped resilient heat deflector shield is secured to an engine and related carburetor; the shield has at least two positions one of which deflects the flow of hot air away from the carburetor while a second position, determined by the resilient deformation of the shield, enables ready excess to externally accessible adjustment means carried by the carburetor.

10 Claims, 3 Drawing Figures BACKGROUND OF THE INVENTION In many engines, as for example those employed in snowmobiles or the like, there is a considerable flow of hot air (the heat being generated by the engine) the path of which, of necessity, is more often than not directed against and past the associatd fuel control device which may be a carburetor. The temperature of such hot air impinging on, for example, the carburetor and the relatively high volume rate of flow thereof frequently causes the fuel within, for example, the associated carburetor fuel reservoir, nd possibly the various fuel metering passages therein, to at least partially vaporize. This, in turn, may result in severely altered fuel metering characteristics causing unstable engine operation, or, it may actually result in a total vapor lock condition causing a total engine shut-down.-

Attempts to re-direct the path of flow of such hot air in order to eliminate the deleterious effects on the carburetor have not proven to be successful in that the compartment housing the engine is usually quite confining and fans driven by the engine for purposes of cooling the engine are usually positioned so as to inherently cause the flow of hot air to be directed against the carburetor. t

Accordingly, the invention herein disclosed and claimed is primarily directed to the solution of the aboveas well as other related problems.

SUMMARY OF THE INVENTION According to the invention, a heat deflector shield for use in combination with an internal combustion engine and an associated fuel metering device, comprises a generally resilient member operatively connected to said fuel metering device, said resilient membercomprising a wall adapted to pass generally around said associated fuel metering device when said resilient member is operatively connected to said fuel metering device, and said wall being resiliently deflectablefrom a first position wherein said wall serves to deflect away from said fuel metering device the flow of hot air generated by said engine to a-second position wherein said wall exposes at least a greater portion of said fuel metering device .than that which was exposed when said wall was in'said first position thereby enabling greater external accessibility to said fuel metering device.

Various general and specific objects and advantages of the invention will become apparent when reference is made to the following detailed description considered in conjuction with the accompanying drawings.

DESCRIPTION vOF THE DRAWINGS In the drawings, wherein for purposes of clarity certain elements and details may be omitted from one or more views:

FIG. 1 is a fragmentary elevational view of a snowmobile having an internal combustion engine equipped with a heat deflector shield constructed in accordance with the teachings of the invention;

FIG. 2 is an enlarged elevational view of the heat shield of FIG. 1 taken generally on the plane of line 2-2 of FIG. 1 and looking in the direction of the arrows; and

2 FIG. 3 is a cross-sectional view, taken generally on the plane of line 3--3 of FIG. 2, with certain positions thereof shown in elevation.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now in greater detail to the drawings, FIG. 1, fragmentarily, typically illustrates a smowmobile 10 having a forward compartment 12 generally housing a suitable internal combustion engine 14, which, in turn, is operatively connected, as by power transmission means 16, to a power drive belt or track 18 disposed under a major portion of the snowmobile body 20 and adapted for engagement with the particular surface being traversed by the snowmobile.

Handle-bar steering gear means 22 are disposed forwardly of a seat or cushion 24 permitting the vehicle operator to steer the vehicle through an associated ski 26.

The engine 14 is provided with a suitable fuel control device 28, such as, for example, a carburetor, and an associated heat shield 30 constructed in accordance with the teachings of the invention.

FIGS. 2 and 3, respectively end elevational and crosssectional views taken on lines 2-2 and 3-3 of FIGS. land 2, illustrate the preferred embodiment of the heat shield 30 as being comprised of a generally annular cup-shaped configuration having a base portion 32 with an aperture 34 formed therethrough. A generally annular wall 36 formed integrally with base 32 preferably progressively flares radially outwardly from its juncture with base 32 to its open inlet end 38. As best depicted in FIG. 3, an annular bead 40 is formed integrally at and with the terminal end of annular wall 36 so as to thereby provide a degree of rigidity to the annular wall, in case such added rigidity is deemed necessary or desired. Further, as also best shown in FIG. 3, the preferred embodiment of the heat shield 30 has the general area comprising the juncture 42 between the base portion 32 and wall v36 of a cross-sectional thickness greater than the cross-sectional thickness of the wall 36.

An-adapter-like mounting member 44, of relatively low heat. conductivity, is formed as by a generally medially situated main body portion 46 having a groove 48 formed generally peripherally therein thereby defining oppositely disposed radially extending abutment-like flange surfaces 50 and 52. The cup-like deflector shield 30 is preferably molded of neoprene (an oil-resistant synthetic rubber made by polymerizing chloroprene); however, any suitable relatively resilient material may be used. Accordingly the natural resilience of the material forming the shield 30 permits the base portion 32 to be resiliently stretched thereby enabling the aperture 34 to pass over the comparatively larger body 46 and to be received within groove 48 as to be axially confined between opposed surfaces 50 and 52.

Preferably, end face 54 of body 46 has a first raised portion 56 formed thereon, of a peripheral configuration best seen in FIG. 2, which serves as a mounting surface against which the mounting flange 58 of the carburetor 28' is situated. Similarly, opposite end face 60 has a second raised portion 62, of a configuration like that of portion 56, which is intended for mounting against a cooperating mounting surface 64 of the engine 14.

Spacer-like retainer member 44, which may be of any suitable material such as, for example, molded fiber or phenolic, has

clearance apertures

66 and 68 formed therethrough which accommodate mounting screws 70 and 72 (shown in transverse cross-section). That is, when the carburetor 28 is placed onto raised mounting portion 56,

screws

70 and 72 are inserted in the flange 58 of carburetor 28 as to extend therebeyond, through aligned apertures in mounting member 44 and into additional aligned internally threaded apertures formed generally in engine mounting surface 64 for threadable engagement therewith. When the carburetor 28 is thusly mounted and secured to engine 14, the induction passage of the carburetor is placed in axial alignment with aperture 74 formed in mounting member 44 (which then forms a continuation of the induction passage) and the intake passage 76 of engine 14.

Additionally, mounting member 44 may be provided with a plurality of apertures or

passages

78 and 80 formed therethrough as to complete communication between respective first respective conduit portions formed in the carburetor 28 and second respective conduits formed in the engine leading to a source of engine or intake vacuum. Such vacuum communicated from the engine may be employed for actuation of appropriate mechanism associated with the carburetor and effective for pumping fuel from a related source of fuel to a fuel reservoir 82 carried, for example, by the carburetor.

As was previously stated, in many engines, as for example those employed in snowmobiles or the like, there is a considerable flow of hot air (the heat being generated by the engine) the path of which, of necessity, is more often than not directed against and past the associated fuel control device which may be a carburetor. The temperature of such hot air impinging on, for example, the carburetor and the relatively high volume rate of flow thereof frequently causes the fuel within, for example, the associated carburetor fuel reservoir, and possibly the various fuel metering passages therein, to at least partially vaporize. This, in turn, may result in severely altered fuel metering characteristics causing unstable or rough" engine operation or, it may actually result in a total vapor lock condition causing a total engine shut-down.

Attempts to re-direct the path of flow of such hot air in order to eliminate the deleterious effects on the carburetor have not proven to be successful in that the compartment housing the engine is usually quite confining and fans driven by the engine for purposes of cooling the engine are usually positioned so as to inherently cause the flow of hot air to be directed against the carburetor.

Accordingly, the invention herein disclosed provides means forming a deflector type heat shield, situated generally about the carburetor, as well as the solution of problems attendant the provision of such a heat shield. That is, since any fuel metering device, especially a carburetor, has many externally accessible adjustment means (in the form of screw-like metering restrictions and the like) for adjusting the fuel metering device to attain optimum performance, the placement of a heat deflector shield about, for example, a carburetor raises the problem of rendering such previously externally accessible adjustment means no longer accessible.

However, the invention as herein disclosed and claimed overcomes all of such problems; that is, not only does the shield deflect the hot air, depicted generally by the broad arrows in FIG. 3, but it is also capable of being resiliently deformed, or bent backward to assume, for example, a position fragmentarily illustrated in phantom line at 36a. The shield 30, when thusly resiliently deformed effectively uncovers the fuel metering device or carburetor 28 exposing all of the related adjustment means and thereby making such again readily externally adjustable.

Among other embodiments and modifications of the invention which are contemplated is the formation of a heat shield of a configuration other than annular as specifically disclosed. Further it should be apparent that the heat shield need not be secured to either the engine or carburetor as specifically shown.

Although only one preferred embodiment of the invention has been disclosed and described, it is apparent that other embodiments and modifications of the invention are possible within the scope of the appended claims.

I claim:

1. A heat deflector shield in combination with an internal combustion engine and an associated fuel metering device, comprising a generally resilient member operatively connected to said fuel metering device, said resilient member comprising a wall adapted to pass generally around said associated fuel metering device when said resilient member is operatively connected to said fuel metering device, and said wall being resiliently deflectable from a first position wherein said wall serves to deflect away from said fuel metering device the flow of hot air generated by said engine to a second position wherein said wall exposes at least a greater portion of said fuel metering device than that which was exposed when said wall was in said first position thereby enabling greater external accessibility to said fuel metering device.

2. A heat deflector shield according to claim 1, wherein said wall is of an annular configuration circumscribing said fuel metering device.

3. A heat deflector shield according to claim 2 wherein said annular wall is generally tapered as to form a segment of a cone thereby defining at opposite ends thereof a first axial and diametrically larger than a second axial end thereof.

4. A heat deflector shield according to claim 3, wherein the larger end of said tapered annular wall includes a cross-sectionally enlarged reinforcing bead formed generally peripherally about said larger end.

5. A heat deflector shield according to claim 1, wherein said resilient member is ofa generally cup-like configuration having an end wall portion and an annular wall formed integrally therewith, said annular wall being so arranged with respect to said end wall as to have the axis of said annular generally normal to said end wall.

6. A heat deflector shield according to claim 5, wherein said end wall has an aperture formed therethrough, said aperture being effective for operatively engaging associated mounting means for thereby operatively connecting said resilient cup-like member to said fuel metering device.

7. A heat deflector shield according to claim 6, wherein a spacer member having a second aperture formed therethrough and defining a passageway comgenerally defining the juncture of said annular wall and said end wall is of a cross-sectional thickness greater than the cross-sectional thickness of said annular wall.

9. A heat deflector shield according to claim 5, wherein that portion of said cup-like resilient member generally defining the juncture of said annular wall and said end wall is of a cross-sectional thickness greater than the respective cross-sectional thicknesses of either said annular wall or said end wall.

10. A heat deflector shield according to claim 1, wherein said resilient member is comprised of neoprene.

Claims

5. A heat deflector shield according to claim 1, wherein said resilient member is of a generally cup-like configuration having an end wall portion and an annular wall formed integrally therewith, said annular wall being so arranged with respect to said end wall as to have the axis of said annular generally normal to said end wall.

7. A heat deflector shield according to claim 6, wherein a spacer member having a second aperture formed therethrough and defining a passageway communicating between said engine and said fuel metering device comprises said mounting means.

8. A heat deflector shield according to claim 5, wherein that portion of said cup-like resilient member generally defining the juncture of said annular wall and said end wall is of a cross-sectional thickness greater than the cross-sectional thickness of said annular wall.