US2799486A - Fuel mixing valve for internal combustion engine - Google Patents

Fuel mixing valve for internal combustion engine Download PDF

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US2799486A
US2799486A US471693A US47169354A US2799486A US 2799486 A US2799486 A US 2799486A US 471693 A US471693 A US 471693A US 47169354 A US47169354 A US 47169354A US 2799486 A US2799486 A US 2799486A
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fuel
tube
port
passage
valve
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US471693A
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Gerald P Teschendorf
Daniel L Donovan
Henry O Pohrt
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Continental Motors Corp
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Continental Motors Corp
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02MSUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M17/00Carburettors having pertinent characteristics not provided for in, or of interest apart from, the apparatus of preceding main groups F02M1/00 - F02M15/00
    • F02M17/44Carburettors characterised by draught direction and not otherwise provided for, e.g. for model aeroplanes
    • F02M17/48Carburettors characterised by draught direction and not otherwise provided for, e.g. for model aeroplanes with up- draught and float draught, e.g. for lawnmower and chain saw motors
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02MSUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M7/00Carburettors with means for influencing, e.g. enriching or keeping constant, fuel/air ratio of charge under varying conditions
    • F02M7/02Carburettors having aerated fuel spray nozzles
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S261/00Gas and liquid contact apparatus
    • Y10S261/68Diaphragm-controlled inlet valve

Definitions

  • This invention relates to a fuel mixing valve for an internal combustion engine and has for its objectthe provision of a mixing valve operable to providefor improved engine performance, and more particularly to provide for quick throttle response to insure positive operation of the engine when the throttle is advanced after idling.
  • the fuel mixing valves as presently employed are mostly deficient in this respect with the result that many of the better type power plants employ a float carburetor, which is relatively more complex and expensive than a fuel mixing valve.
  • the present invention provides a fuel mixing valve capable of giving satisfactory performance equal in most respects to the better constructed carbureted engines.
  • Fig. l is a plan view of the improved fuel mixing valve embodying the principles of the invention
  • The'body 11 is provided with an air passage 15 having an air intake 16 through which air is drawn intothe fuel mixing valve from a suitable air cleaner 17.
  • a butterfly valve '18 is associated with the'outlet '19 preferably immediately upstream of the outlet Where same is joined to the engine intake manifold duct 14. This butterfly valve is suitably actuated through a lever 20, which is in turn normally adjustable by the operator in the customary manner to control engine operation.
  • a fuel intake device 25 which comprises an e1on-.
  • gated tube or pipe 26 extending normal to the passage 15, and bridging said passage as best illustrated in Figs. 2 and 3.
  • Said tube 26 extends below the fuel mixing valve assembly and projects into the fuel tank 13 (see Fig. 3). Midway of the tube, the internal bore is reduced in diam- Patented July re, 1957 eter and provides a seat 27 in which a manually adjustable needle valve 28 is seated to regulate or meter the fuel which may be drawn by said valve into the internal fuel passage portion 29 in said tube 26, where same traverses the air passage 15.
  • the body 10 is provided with an auxiliary drilled passage 30 lying preferably immediately below the passage 15 and open to the bore 31 through which tube 26 extends and opens to the enlarged bore 32 downstream of the butterfly valve 18 (see Fig. 2).
  • the internal bore 29 of the tube 26, above the needle valve seat 27 is open to this passage 30 by a small hole or port 35. Opening into passage 15 is a hole or port 36 facing downstream of said valve assembly.
  • hole or port 36 is another hole 37 facing partially upstream of the valve assembly, whereby to admit a relatively small amount of air into the internal bore 29 of tube 26 where same is mixed with the fuel and conducted as a relatively fuel and air mixture through passage 33 directly into bore 32 beyond or downstream of said butterfly valve 18, serving to provide an adequate fuel and air mix to the engine for idling operation, when the butterfly valve or throttle valve 18 is closed.
  • a fuel and air mixing valve assembly comprising a valve body having a main passage therethrough openly connecting said air intake system with said intake manifold, a throttle valve in said passage at the end nearest said intake manifold, and a single hollow fuel induction tube in said passage and upstream of said throttle valve, said hollow tube comprising a mixing chamber and adapted to open at one end into a fuel supply contained in said fuel tank, the interior of said tube comprising a single auxiliary fuel induction pump, a port in said tube opening into said valve body passage and facing substantially upstream thereof, a second port in said tube opening into said valve body passage and facing'substantially downstream thereof, and a third port in said tube intermediate said tube open end and said first two ports, a fuel passage in said valve body open at one end into said intake manifold and openly connected at the other end to the third port aforesaid, said second port being located in intermediate said first and third ports, and .
  • a fuel and air mixing valve assembly comprising a valve body having a main passage therethrough openly connecting said air intake system with said intake manifold, a throttle valve in said passage at the end nearest said intake manifold, and a single hollow fuel induction tube in said passage and upstream of said throttle valve, said tube comprising a mixing chamber and adapted to open at one end into a fuel supply contained in said fuel tank, the interior of said tube comprising a single auxiliary fuel induction pump, a port in said tube opening into said valve body passage and facing substantially upstream thereof, a second port in said tube opening into said valve body passage and facing substantially downstream thereof, and a third port in said tube intermediate said tube open end and said first two ports, a fuel passage in said valve body open at one end into said intake manifold and openly connected at the other end to the third port aforesaid, said second port being located intermediate said first and third ports, and a manually adjusted needle valve in said
  • a fuel and air mixing valve assembly comprising a valve body having a main passage therethrough openly connecting said air intake system with said intake manifold, a throttle valve in said passage at the end nearest said intake manifold, and a single hollow fuel induction tube in said passage and upstream of said throttle valve, said hollow tube comprising a mixing chamber and adapted to open at one end into a fuel supply contained in said fuel tank, the interior of said tube comprising a single auxiliary fuel induction pump, a port in said tube opening into said valve body passage and facing substantially upstream thereof, a second port in said tube opening into said passage and facing substantially downstream thereof, and a third port in said tube intermediate said tube open end and said first two ports, a fuel passage in said valve body open at one end into said intake manifold and openly connected at the other end to the third port aforesaid, said second port being located intermediate said first and third ports, and a manually adjusted needle valve in said fuel
  • a fuel and air mixing valve assembly comprising a valve body having a main passage therethrough openly connecting said air intake system with said intake manifold, a throttle valve in said passage at the end nearest said intake manifold, and a single hollow fuel induction tube in said passage and upstream of said throttle valve, said hollow tube comprising a mixing chamber and adapted to open at one end into a fuel supply contained in said fuel tank, the interior of said tube comprising a single auxiliary fuel induction pump, a port in said tube opening into said valve body passage and facing substantially upstream thereof, a second port in said tube opening into said passage and facing substantially downstream thereof, and a third port in said tube intermediate said tube open end and said first two ports, a fuel passage in said Valve body open at one end into said intake manifold and openly connected at the other end to the third port aforesaid, and a manually adjusted needle valve in said fuel induction tube intermediate said third port and said tube open
  • a fuel and air mixing valve assembly comprising a valve body having a main passage therethrough openly connecting said air intake system with said intake manifold, a throttle valve in said passage at the end nearest said intake manifold, and a single hollow fuel induction tube in said passage and upstream of said throttle valve, said hollow tube comprising a mixing chamber and adapted to open at one end into a fuel supply contained in said fuel tank, the interior of said tube comprising a single auxiliary fuel induction pump, a port in said tube opening into said valve body passage and facing substantially upstream thereof, a second port in said tube opening into said passage and facing substantially downstream thereof, and a third port in said tube intermediate said tube open end and said first two ports, a fuel passage in said valve body open at one end into said intake manifold and openly connected at the other end to the third port aforesaid, said second port being located intermediate said first and third ports, and a manually adjusted needle valve in said fuel

Description

July 16, 1957 G. P. TESCHENDQRF E'I'AL 2,7 ,4
FUEL MIXING VALVE FOR INTERNAL COMBUSTION ENGINE Filed Nov. 29, 1954 Danie? Lpanovan BY 71ency O. 7%]7ri ATTORNEYS United States Patent FUEL lVIlXlNG VALVE FOR INTERNAL COMBUSTION'ENGINE Gerald P. Teschendorf, St. Clair Shores, Daniel L. Donovan, Hazel Park, and Henry 0. Pohrt, Ferndale, Mich, assignors to Continental Motors Corporation, Detroit and Muskegon, Mich., a corporation of Virginia Application November 29, 1954, Serial No. 471,693
5 Claims. (Cl. 261-41) This invention relates to a fuel mixing valve for an internal combustion engine and has for its objectthe provision of a mixing valve operable to providefor improved engine performance, and more particularly to provide for quick throttle response to insure positive operation of the engine when the throttle is advanced after idling.
In the small engine field, particularly with engines employedfor powering lawnmowers and other types of manually controlled cultivating equipment, such machines are often operated at idling speeds and then quickly advanced. It is quite desirable in the operation of such machines or equipment to have a power plant immediately responsive to a sudden throttle advance, and such power plants are only operable under such conditions with proper and efiicient carburetion.
The fuel mixing valves as presently employed are mostly deficient in this respect with the result that many of the better type power plants employ a float carburetor, which is relatively more complex and expensive than a fuel mixing valve. The present invention provides a fuel mixing valve capable of giving satisfactory performance equal in most respects to the better constructed carbureted engines.
For a more detailed understanding of this invention, reference may be made to the accompanying drawing, illustrating a preferred embodiment of the invention, in which like characters refer to like parts through the several views, and in which Fig. l is a plan view of the improved fuel mixing valve embodying the principles of the invention,
- directly on afuel tank 13, and arranged to deliver a fuel and air mixture to the intake manifold or duct 14 of an internal combustion engine (not shown).
The'body 11 is provided with an air passage 15 having an air intake 16 through which air is drawn intothe fuel mixing valve from a suitable air cleaner 17. A butterfly valve '18 is associated with the'outlet '19 preferably immediately upstream of the outlet Where same is joined to the engine intake manifold duct 14. This butterfly valve is suitably actuated through a lever 20, which is in turn normally adjustable by the operator in the customary manner to control engine operation.
Medially of the air inlet 16 and outlet 19, there is provided a fuel intake device 25, which comprises an e1on-.
gated tube or pipe 26 extending normal to the passage 15, and bridging said passage as best illustrated in Figs. 2 and 3. Said tube 26 extends below the fuel mixing valve assembly and projects into the fuel tank 13 (see Fig. 3). Midway of the tube, the internal bore is reduced in diam- Patented July re, 1957 eter and provides a seat 27 in which a manually adjustable needle valve 28 is seated to regulate or meter the fuel which may be drawn by said valve into the internal fuel passage portion 29 in said tube 26, where same traverses the air passage 15.
The body 10 is provided with an auxiliary drilled passage 30 lying preferably immediately below the passage 15 and open to the bore 31 through which tube 26 extends and opens to the enlarged bore 32 downstream of the butterfly valve 18 (see Fig. 2). The internal bore 29 of the tube 26, above the needle valve seat 27 is open to this passage 30 by a small hole or port 35. Opening into passage 15 is a hole or port 36 facing downstream of said valve assembly. Preferably just above the hole or port 36 is another hole 37 facing partially upstream of the valve assembly, whereby to admit a relatively small amount of air into the internal bore 29 of tube 26 where same is mixed with the fuel and conducted as a relatively fuel and air mixture through passage 33 directly into bore 32 beyond or downstream of said butterfly valve 18, serving to provide an adequate fuel and air mix to the engine for idling operation, when the butterfly valve or throttle valve 18 is closed.
On opening of the valve 18 fuel is drawn through port 36 for direct mixture with the air in passage 15 and at this time any air fiow from port 37 to port 35 is substantially reversed and any air admitted through port 37 is mixed with the fuel in bore 29 and exhausted through port 36, since the suction effect at port 36 is greater than the suction effect at port 35.
Although but one form of the invention is illustrated and described in the foregoing specification, it is apparent to those skilled in the art to which this invention pertains that various changes and modifications may be made without departing from the spirit of said invention or from the scope of the appended claims.
We claim:
1. In an internal combustion engine having a fuel tank, an air intake system, and an intake manifold, a fuel and air mixing valve assembly comprising a valve body having a main passage therethrough openly connecting said air intake system with said intake manifold, a throttle valve in said passage at the end nearest said intake manifold, and a single hollow fuel induction tube in said passage and upstream of said throttle valve, said hollow tube comprising a mixing chamber and adapted to open at one end into a fuel supply contained in said fuel tank, the interior of said tube comprising a single auxiliary fuel induction pump, a port in said tube opening into said valve body passage and facing substantially upstream thereof, a second port in said tube opening into said valve body passage and facing'substantially downstream thereof, and a third port in said tube intermediate said tube open end and said first two ports, a fuel passage in said valve body open at one end into said intake manifold and openly connected at the other end to the third port aforesaid, said second port being located in intermediate said first and third ports, and .a manually adjusted needle valve in said fuel induction tube intermediate said third port and said tube open end, all of said ports at all times openly communicating with said mixing chamber whereby said second and third ports discharge a fuel and air mixture into said manifold.
2. In an internal combustion engine having a fuel tank, an air intake system, and an intake manifold, a fuel and air mixing valve assembly comprising a valve body having a main passage therethrough openly connecting said air intake system with said intake manifold, a throttle valve in said passage at the end nearest said intake manifold, and a single hollow fuel induction tube in said passage and upstream of said throttle valve, said tube comprising a mixing chamber and adapted to open at one end into a fuel supply contained in said fuel tank, the interior of said tube comprising a single auxiliary fuel induction pump, a port in said tube opening into said valve body passage and facing substantially upstream thereof, a second port in said tube opening into said valve body passage and facing substantially downstream thereof, and a third port in said tube intermediate said tube open end and said first two ports, a fuel passage in said valve body open at one end into said intake manifold and openly connected at the other end to the third port aforesaid, said second port being located intermediate said first and third ports, and a manually adjusted needle valve in said fuel induction tube intermediate said third port and said tube open end, said fuel induction tube positioned substantially normal to the longitudinal axis of said valve main passage and substantially vertical therein, all of said ports at all times openly communicating with said mixing chamber whereby said second and third ports discharge a fuel and air mixture into said manifold.
3. In an internal combustion engine having a fuel tank, an air intake system, and an intake manifold, a fuel and air mixing valve assembly comprising a valve body having a main passage therethrough openly connecting said air intake system with said intake manifold, a throttle valve in said passage at the end nearest said intake manifold, and a single hollow fuel induction tube in said passage and upstream of said throttle valve, said hollow tube comprising a mixing chamber and adapted to open at one end into a fuel supply contained in said fuel tank, the interior of said tube comprising a single auxiliary fuel induction pump, a port in said tube opening into said valve body passage and facing substantially upstream thereof, a second port in said tube opening into said passage and facing substantially downstream thereof, and a third port in said tube intermediate said tube open end and said first two ports, a fuel passage in said valve body open at one end into said intake manifold and openly connected at the other end to the third port aforesaid, said second port being located intermediate said first and third ports, and a manually adjusted needle valve in said fuel induction tube intermediate said third port and said tube open end, said fuel induction tube positioned substantially normal to the longitudinal axis of said valve main passage and substantially vertical therein, said first upstreamfacing port relatively offset from the longitudinal axis of said main passage and in a substantially horizontal plane containing said main passage longitudinal axis, all of said ports at all times openly communicating with said mixing chamber whereby said second and third ports discharge a fuel and air mixture into said manifold.
4. In an internal combustion engine having a fuel tank, an air intake system, and an intake manifold, a fuel and air mixing valve assembly comprising a valve body having a main passage therethrough openly connecting said air intake system with said intake manifold, a throttle valve in said passage at the end nearest said intake manifold, and a single hollow fuel induction tube in said passage and upstream of said throttle valve, said hollow tube comprising a mixing chamber and adapted to open at one end into a fuel supply contained in said fuel tank, the interior of said tube comprising a single auxiliary fuel induction pump, a port in said tube opening into said valve body passage and facing substantially upstream thereof, a second port in said tube opening into said passage and facing substantially downstream thereof, and a third port in said tube intermediate said tube open end and said first two ports, a fuel passage in said Valve body open at one end into said intake manifold and openly connected at the other end to the third port aforesaid, and a manually adjusted needle valve in said fuel induction tube intermediate said third port and said tube open end, said fuel induction tube positioned substantially normal to the longitudinal axis of said valve main passage and substantially vertical therein, said first upstream-facing port relatively offset from the longitudinal axis of said main passage and in a substantially horizontal plane containing said main passage longitudinal axis, said second downstream-facing port contained in a horizontal plane below and parallel to the horizontal plane containing the main passage longitudinal axis aforesaid, all of said ports at all times openly communicating with said mixing chamber whereby said second and third ports discharge a fuel and air mixture into said manifold.
5. In an internal combustion engine having a fuel tank, an air intake system, and an intake manifold, a fuel and air mixing valve assembly comprising a valve body having a main passage therethrough openly connecting said air intake system with said intake manifold, a throttle valve in said passage at the end nearest said intake manifold, and a single hollow fuel induction tube in said passage and upstream of said throttle valve, said hollow tube comprising a mixing chamber and adapted to open at one end into a fuel supply contained in said fuel tank, the interior of said tube comprising a single auxiliary fuel induction pump, a port in said tube opening into said valve body passage and facing substantially upstream thereof, a second port in said tube opening into said passage and facing substantially downstream thereof, and a third port in said tube intermediate said tube open end and said first two ports, a fuel passage in said valve body open at one end into said intake manifold and openly connected at the other end to the third port aforesaid, said second port being located intermediate said first and third ports, and a manually adjusted needle valve in said fuel induction tube intermediate said third port and said tube open end, said fuel passage substantially parallel to the longitudinal axis of said main passage, and said third port facing in a substantially downstream direction relative to said main passage, all of said ports at all times openly communieating with said mixing chamber whereby said second and third ports discharge a fuel and air mixture into said manifold.
References Cited in the file of this patent UNITED STATES PATENTS 1,523,095 Zarracina Jan. 13, 1925 1,607,830 Kessel Nov. 23, 1926 1,672,923 Zarracina Jan. 12, 1928 1,752,551 Ensign et a1. Apr. 1, 1930 2,529,242 Brown et al. Nov. 7, 1950
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3093699A (en) * 1961-01-30 1963-06-11 Acf Ind Inc Carburetor
US3231250A (en) * 1962-08-30 1966-01-25 Acf Ind Inc Carburetor
US3342465A (en) * 1966-06-17 1967-09-19 Acf Ind Inc Carburetor

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1523095A (en) * 1919-06-21 1925-01-13 Zarracina Isidro Rodriguez Carburetor
US1607830A (en) * 1926-11-23 Carburetor
US1672923A (en) * 1922-05-12 1928-06-12 Zarracina Isidro Rodriguez Carburetor
US1752551A (en) * 1921-05-19 1930-04-01 Ensign Carburetor Company Carburetor
US2529242A (en) * 1949-09-10 1950-11-07 Brlggs & Stratton Corp Carburetor

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1607830A (en) * 1926-11-23 Carburetor
US1523095A (en) * 1919-06-21 1925-01-13 Zarracina Isidro Rodriguez Carburetor
US1752551A (en) * 1921-05-19 1930-04-01 Ensign Carburetor Company Carburetor
US1672923A (en) * 1922-05-12 1928-06-12 Zarracina Isidro Rodriguez Carburetor
US2529242A (en) * 1949-09-10 1950-11-07 Brlggs & Stratton Corp Carburetor

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3093699A (en) * 1961-01-30 1963-06-11 Acf Ind Inc Carburetor
US3231250A (en) * 1962-08-30 1966-01-25 Acf Ind Inc Carburetor
US3342465A (en) * 1966-06-17 1967-09-19 Acf Ind Inc Carburetor

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