US3235237A

US3235237A - De-popper valve

Info

Publication number: US3235237A
Authority: US
Inventors: Vincent A Goetz; Thomas R Mein
Original assignee: Holley Carburetor Co
Current assignee: Holley Performance Products Inc
Priority date: 1965-02-15
Filing date: 1965-02-15
Publication date: 1966-02-15
Anticipated expiration: 1983-02-15

Description

United States Patent Ofi" 7 3,235,237 Patented Feb. 15, 1966 ICC p 3,235,237 DE-POPPER VALVE Vincent A. Goetz, Detroit, and Thomas R. Mein, Dearborn, Mich, assignors to Holley Carburetor Company,

Warren, Mich, a corporation of Michigan Continuation of application Ser. No. 119,392, June 26,

1961. This application Feb. 15, 1965, Ser. No. 436,410

2 Claims. (Cl. 261-41) This application is a continuation of US. application Serial No. 119,392, now abandoned, filed on June 26, 1961 in the names of Vincent A. Goetz and Thomas R. Mein.

This invention relates to fuel systems for internal combustion engines, and more particularly to means for supplying additional fuel under certain engine operating conditions.

In the past, internal combustion engine fuel systems have usually required the use of a so-called power valve which was responsive to the relatively low manifold vacuum existing at high engine load when the throttle valve is open to supply fuel in addition to the normal fuel supplied through the main fuel system. Also, it was sometimes desirable to have a separate override valve responsive to high manifold vacuum due to a closed throttle on deceleration to supply additional fuel during deceleration so as to prevent backfiring. Although both the power valve and the override valve were desirable, the override valve was very often omitted from the fuel supply system because of its added expense.

Override, which usually occurs during down hill deceler-ation, is the condition where the vehicle drives the engine at a relatively high speed with the throttle closed so that the intake manifold vacuum is high, usually exceeding a value of about 21of mercury.

Backfiring is principally caused by the formation of a mixture in the cylinders that is too lean to be ignited by the spark, and the passing of this lean mixture into the exhaust pipe and mufller where it is ignited by subsequent firing of the engine. The lean mixtures are usually produced by the return of exhaust gases from the manifold to the cylinders when the intake manifold vacuum is high. Backfiring can he eliminated by enriching the mixture during overrun so that it is combustible in the cylinders after it is leaned out by the exhaust gases.

Accordingly, it is an object of this invention to provide a means of controlling the flow of fuel at various engine vacuums in order to meet special engine fuel requirements and to prevent overrun backfiring through the exhaust system. 7

It is a furthefobject of this invention to provide a single device which is relatively simple in construction and inexpensive to manufacture and which will operate both as an override valve and a power valve.

Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawings, wherein:

FIGURE 1 is an elevational view in partial cross-section of a carburetor embodying the invention;

FIGURE 2 is an enlarged cross-sectional view illustrating the invention in greater detail;

FIGURE 3 is a cross-sectional view taken on the plane of line 3-3 of FIGURE 2 and looking in the direction of the arrows.

With the foregoing general description of the inven- Cir tion in mind, reference is now made to the drawings.

housing 26. The usual idle and transfer fuel systems would, of course, be present, but they are not shown.

The control lever 30 actuates throttle plate 18, and it is held in the closed throttle position by spring 32. Passage 34 is themain fuel supply to discharge nozzle 16, and it communicates with passage 36 having the main metering restriction 33 through which fuel from the reservoir 24 is metered. Passage 36 communicates with a branch passage 37 having a restriction 39 and leading to the novel combination power and override valve assembly 23. Passage 40 having a restriction 42 therein connects from assembly 28 to a discharge port 46 disposed downstream of the closed throttle 13. Conduit 48 leads to the manifold vacuum port 50 on the engine side of the throttle valve 18. Gasket 52 seals between assembly 28 and fuel bowl 26.

In FIGURES 2 and 3, which illustrate on an enlarged scale the combination power and override valve assembly 28 contemplated by the invention, main housing 56 is formed to include a recess 58 so as to form a chamber 60 when the diaphragm 62 has the periphery thereof clamped in any suitable manner between the outer edges of housing 56 and cover 64. Housing 56 has formed therein an opening 54 that connects to passage 37 and main

fuel supply passages

36 and 34. A passage 66 connects between cylinder 68 and chamber 60. Cylinder 68 has one end formed as seat 70 for the main valve 72 which, when open, allows cylinder 68 to be in communication with the :fuel reservoir 24. Passages 74 connect cylinder 6% with the fuel conduit 4-0.

Fixed to the center of diaphragm 62 in any suitable manner is one end of diaphragm rod 76 which has fixed thereto or formed therewith a piston valve 78, which is located in cylinder 68 and which has passages 80 formed therethrough so that the chamber 67 communicates with chamber 69. Flange portion 82 of rod 76 has fixed thereto a rubber or other suitable valve 84 which normally closes the passage 86 formed in main valve 72 through which additional fuel fromreservoir 24 may flow.

Rod 76 extends through passage 86 and into recess 88 of valve 72 which contains a resilient member, such as spring 99, compressed between the bottom wall of recess 88 and spring retainer 1% secured at the free end of rod 76. The function of spring 90' is to keep valve 84 normally seated to close passage 86. 1

Main valve 72 may have a flanged portion 102 which provides an abutment for one end of the relatively weak resilient member, such as spring 104, having its other end abutting the end 105 of main housing 56 threaded into the bottom part of fuel bowl 26. The force of spring 104 tends to keep the valve 72 away from its seat 70 so that fuel may fiow through the openings 106, valve 72, chamber 69, passages 80, chamber 67, passage 66, chamber 60, opening 54 and into

conduits

37, 36 and 34,

Cover 64 has a recess 108 which becomes chamber 110 when it is fixed to the housing 56 with diaphragm 62 clamped therebetween so that one side 112 of diaphragm 62 becomes a wall of chamber 110. Boss 114 of cover 64 is formed with a passage 116 which connects the chamber 110 with pipe 48 leading to manifold vacuum port 50.

The operation of the invention is such that when the engine is operating normally at a manifold vacuum of approximately 8 to 20 inches of mercury, the elements of the assembly 28 are in the position shown in FIGURE 2. That is, chamber 110 of which the diaphragm 62 forms one wall is partially evacuated, causing rod 76 to move downwardly and position valve 78 so that it blocks off the passages 74; at the same time, the force of spring 90 causes valve 72 to engage seat 70 so as to prevent added fuel from flowing to the main fuel system 34 and nozzle 16.

When the vacuum drops below some predetermined value (for example, 8 inches of mercury) as it does when the throttle 18 is opened wide upon an increase in engine load, the force of spring 99 overcomes the force of the vacuum acting on diaphragm 62 and causes rod 76 to move upwardly. This permits spring 104 to unseat valve 72 and allows fuel to fiow through chamber 6?, passages 80, chamber 67, passage 66, chamber 60, opening 54,

conduits

36 and 34 and out nozzle 16. The upward movement of rod 76 does not, however, open passages 74 because of stops 118 limiting the upward travel of diaphragm 62; that is, passages 74 are still closed by piston valve 78 when the diaphragm travel is stopped.

During the override condition, the engine manifold vacuum acting on diaphragm 62 reaches a value of approximately 21 to 25 inches of mercury, which overcomes the force of spring 90 and causes rod 76 to move downwardly. When rod 76 moves downwardly, valve 73 is engaged with the rubber seat 120 so as to prevent fuel flow through passages 80. However, passages 74 are opened when valve 78 is seated upon seat 120. The downward movement of rod 76 also causes valve 84 to move downwardly and open passage 86 so that additional fuel from reservoir 24 may flow through chamber 69, passages 74, annular chamber 122, and conduit 40 leading to the discharge port 46.

It is apparent that the valve construction disclosed herein is very inexpensive and that it is constructed so as to perform the same functions as previously used separate power and override valves; that is, when the engine vacuum is relatively low at wide open throttle, the combination valve assembly of this invention supplies the additional fuel required by the engine. During normal engine operation at intermediate engine vacuums, the combination valve cuts off all extra fuel, and the engine operates on the normal idle, transfer and main fuel metering systems. 011 down hill deceleration or overrun, the engine vacuum is abnormally high, and engine backfiring is likely to result due to a leaned out mixture being supplied to the engine; at this time, the combination valve again supplies the additional fuel required to enrich the mixture and prevent backfiring.

It is also apparent that the amounts of extra fuel supplied and the vacuums required to operate the combination valve are dependent upon the specific design of the various elements thereof. Furthermore, such a valve could be employed to control the air, rather than the fuel,

' first and second chambers, respectively, having said movable member as a common wall, said first housing member having a conduit through which pressure may be transmitted to said first chamber, said second housing member including an outlet opening formed therein and an outwardly-extending element, a passage extending outwardly through the wall of said element, a stem having one end thereof secured to said diaphragm and extending with clearance axially through said element, the surface of said element adjacent said second housing member being formed as a first valve seat, a portion of said stem positioned within said element being formed with an annular valve member thereon adapted to at times engage said first seat and to at times close said passage extending outwardly through said wall of said element, said stem being formed adjacent said annular valve member to provide a second valve member, the inner surface of said element being formed at the free end thereof to provide a second valve seat, a separate valve member positioned over said stem member with clearance, said separate member being held against said second valve member on said stem by a resilient means positioned within said separate member and retained by a shoulder formed on the free end of said stem, and said separate member being urged away from said second seat by a second resilient means disposed between said free end of said element and a shoulder formed on the outside of said separate member.

2. A pressure responsive valve assembly comprising first and second dish-shaped housing members secured together with a movable member therebetween so as to form adjacent first and second chambers, respectively, having said movable member as a common wall, said first housing member having a conduit through which pressure may be transmitted to said first chamber, said second housing member having an outlet opening formed therein and an axially-disposed outwardly-extending cylindrical portion, the free end of which is externally threaded, a plurality of passages extending outwardly through the wall of said cylindrical portion, a stem having one end thereof secured to the center of said diaphragm and extending with clearance axially through said cylindrical portion, the inner surface of said cylindrical portion adjacent said second housing member being formed as a first valve seat, a portion of said stem positioned within said cylindrical portion being formed with an annular valve member thereon adapted to at times engage said first seat and to at times close said passages extending outwardly through said wall of said cylindrical portion, said stern being formed adjacent said annular valve member to provide a second valve member, the inner surface of said cylindrical portion being formed at the free end thereof to provide a second valve seat, a separate hollow valve member positioned over said stem member with clearance, said hollow valve member being held against said second valve member on said stem by a spring positioned within said hollow valve member and retained by a shoulder on the free end of said stem, and said hollow .valve member being urged away from said second seat by a spring disposed between said free end of said cylindrical portion and a shoulder formed on the outside of said hollow valve member.

References Cited by the Examiner UNITED STATES PATENTS 2,345,547 3/1944 Roth et al. 137-4936 X 2,621,911 12/1952 Lindsteadt. 2,623,535 12/1952 Morgan 251 -322 2,631,832 3/1953 Heiger.

FOREIGN PATENTS 855,182 11/1952 Germany.

HARRY B. THORNTON, Primary Examiner.

Claims

1. A PRESSURE RESPONSIVE VALVE ASSEMBLY COMPRISING FIRST AND SECOND HOUSING MEMBERS SECURED TOGETHER WITH A MOVABLE MEMBER THEREBETWEEN SO AS TO FORM ADJACENT FIRST AND SECOND CHAMBERS, RESPECTIVELY, HAVING SAID MOVABLE MEMBER AS A COMMON WALL, SAID FIRST HOUSING MEMBER HAVING A CONDUIT THROUGH WHICH PRESSURE MAY BE TRASMITTED TO SAID FIRST CHAMBER, SAID SECOND HOUSING MEMBER INCLUDING AN OUTLET OPENING FORMED THEREIN AND AN OUTWARDLY-EXTENDING ELEMENT, A PASSAGE EXTENDING OUTWARDLY THROUGH THE WALL OF SAID ELEMENT, A STEM HAVING ONE END THEREOF SECURED TO SAID DIAPHRAGM AND EXTENDING WITH CLEARANCE AXIALLY THROUGH SAID ELEMENT, THE SURFACE OF SAID ELEMENT ADJACENT SAID SECOND HOUSING MEMBER BEING FORMED AS A FIRST VALVE SEAT, A PORTION OF SAID STEM POSITIONED WITHIN SAID ELEMENT BEING FORMED WITH AN ANNULAR VALVE MEMBER THEREON ADAPTED TO AT TIMES ENGAGE SAID FIRST SEAT AND TO AT TIMES CLOSE SAID PASSAGE EXTENDING OUTWARDLY THROUGH SAID WALL OF SAID ELEMENT, SAID STEM BEING FORMED ADJACENT SAID ANNULAR VALVE MEMBER TO PROVIDE A SECOND VALVE MEMBER, THE INNER SURFACE OF SAID ELEMENT BEING FORMED AT THE FREE END THEREOF TO PROVIDE A SECOND VALVE SEAT, A SEPARATE VALVE MEMBER POSITIONED OVER SAID STEM MEMBER WITH CLEARANCE, SAID SEPARATE MEMBER BEING HELD AGAINST SAID SECOND VALVE MEMBER ON SAID STEM BY A RESILIENT MEANS POSITIONED WITHIN SAID SEPARATE MEMBER AND RETAINED BY A SHOULDER FORMED ON THE FREE END OF SAID STEM, AND SAID SEPARATE MEMBER BEING URGED AWAY FROM SAID SECOND SEAT BY A SECOND RESILIENT MEANS DISPOSED BETWEEN SAID FREE END OF SAID ELEMENT AND A SHOULDER FORMED ON THE OUTSIDE OF SAID SEPARATE MEMBER.