US2473761A - Speed control for internalcombustion engines - Google Patents

Description

June 21, 1949. M. MALLORY SPEED CONTROL FQR INTERNAL-COMBUSTION ENGINES Filed Sept. 25, 1947 2 Sheets-Sheet l INVEN rofi. Mar/0r) Maflory By June 21, 1949. MALLORY SPEED CONTROL FOR INTERNAL-COMBUSTION ENGINES 2 Sheets-Shet 2 Fil ed Sept. 25, 1947 FILE. 2.

INVENTOR. Man 0/7 Mafia/'51 Patented June 21, 1949 SPEED CONTROL FOR INTERNAL COBBUSTHON ENGHNES Marion Mallory, Detroit, Mich, 'assignor to The Mallory Research Com corporation of Michigan parry, Detroit, Mich, a

Application September 25, 1947, Serial No. 776,113

11 Claims.

This invention relates to means for stopping the running of an internal combustion engine when a predetermined speed has been attained.

It has heretofore been the practice to control the speed of internal combustion engines by speed governors which actuate the carburetor throttle or a supplemental throttle to reduce the fuel supply to the engine when a predetermined speed has been reached. This form of control is objected to by automobile fleet owners for the reason that the horsepower of the engine is reprovision of means in connection with the car buretor that is automatically actuated to stop the flow of fuel to the carburetor throat or fuel supply passageway to the engine when,"and not until, a predetermined engine speed has been reached so that full engine horsepower is maintained right up to the engine speed limit desired.

The invention is fully described in the following specification and two embodiments thereof illustrated in the accompanying drawings in which I Fig. 1 is a central longitudinal section of an apparatus embodying the invention with parts in full and with the air relief valve of the centrifugal control means'closed; and Fig. 2 is a similar section of a form of the invention in which the centrifugal means is eliminated.

Referring to the drawings, l designates a carburetor casing forming a fuel feed throat or passageway 2 to an associated engine (not shown) and having the customary Venturi restriction 3 therein. Inward from this restriction is the customary throttle valve 4. A fuel feed nozzle 5 isdisposed centrally in the throat 2 adjacent to the inlet end of the restriction 3 and, in the present instance, is provided lengthwise of the throat passageway with an elongated passage 8 open at both ends of the passage 2. The outer end of the passage 6 is shown as abruptly flared, while its inner end portion or that adjacent to the engineis more gradually flared so as to form the nozzle with a Venturi-like passage.

The nozzle 5, in the present instance, .is provided on a wall enlargement of the casing l, and extending into such enlargement from the restricted portion of the nozzle passage- 8 is a fuel feed supply orifice I. This orifice has come munication through a channel 9 with the bottom of the fuel bowl ill of the carburetor so thatsuction created in the orifice by the rush of air through the passage 8 will cause fuel to be drawn thereto from the bowl ID, as well understood in the art. A channel II also extends fromv the orifice 8 or from the outer end portion of the channel 9 to. two idling jets l2, one being at the outer side and the other at the inner side of the throttle valve .4 when in closed or nearly closed position. It is apparent that suction through the Jets l2 and channel I I will draw fuel from the bowl I through said channel 9. This particular form of carburetor or fuel supply for the fuel feed passage 2 is old and is shown more-- ly to illustrate one manner of supplying fuel to the passage.

For the purpose of the automatic control embodying the present invention, there is provided an air bleed channel l extending laterally from the feed channel 9, preferably. adjacent to the communicating end of the channel II, and continuing. through a tube l6 to a centrifugal gov-.

ernor IT. This governor comprises, in the present instance, a casing l8 forming a bearing for a shaft l9 suitably driven from the associated engine, and also forming a chamber in which a cylinder head 2| on the shaft l9 rotates, and this chamber has a vent 22 to the atmosphere. The head 2| has a radially disposed relief chamber 23 therein opening at its outer end into the chamber 20 and communicating at its other end' with the channel 24 in the head'and shaft. This channel has branched connection with an annular sealed-off space 25 in the shaft bearing portion of the casing l8 and thence with the tube l6 through a casing channel 26. A weighted valve has movement in the chamber 23- radially of the head and isnormally held in closing engagement with the adiacent end of the channel 24 by a spring 28. It is apparent that the spring 28 is set to permit the valve to move outwa'rds by centrifugal force, and open the channel-24 to feeding suction in the orifice 8,

permit its venting through the chamber 23 into the casing chamber 20 and then through the opening 22 to the atmosphere when the engine has'reached a predetermined speed.

The venting of the channel 24 relieves the fuel thus stopping the flow of fuel thereto from the supply bowl It, or other suitable source, and consequently stopping the engine, or at least slowing it down to keep its speed within the set limit. As the engine. speed is reduced, the tension of the spring 28 overcomes the centrifugal force on the valve 3 21 and moves the valve inward to close the bleed passage so that the rush of air through the nozzle I again acts to. draw fuel from the carburetor instead of having such drawing or suction action overcome and relieved by the, bleeding which takes place through the channel it, tube It and governor channels when the valve is open.

If the desired speed limit of the engine is 3,000 B. P. M., a spring 28 of suitable tension for the purpose is provided so the valve will move outward to open the vent passage at approximately 3,000 B. P. M., thus relieving the suction in the fuel feed channel so that stoppage of fuel flow takes place and continues until the speed has been reduced sumciently for the valve to close. which may occur at 2,800 or 2,900 R. P. M; When this occurs. the suction will again be restored inthe fuel feed chamber 0 and the feeding of fuel to the passageway 2 in the regular manner wi l then take place. The opening of the relief valve 21 would also stop the flow of fuel to the idling jets I! so that a complete stoppage of fuel supply to 'the engine feed passageway 2 is effected. Should stoppage of the engine occur during the nterrupted fuel feed interval, a renewed starting will be necessary. Such stoppage would soon teach the operator that he could not drive over a set speed and he would therefore watch his speedometer more carefully.

It is apparent that with this control, full horsepower operation of the engine is brought right up to the point where the engine speed is checked, which is a feature highly desirable to most automobile fleet owners.

Another means for bleeding or relieving the fuel feeding suction in the carburetor nozzle channel when a predetermined engine speed is reached, is shown in Fig. 2. In this form, 30 designates the casing forming a passageway 3! for feeding fuel to the engine cylinders; 32 the throttle valve therein; 33 the carburetor fuel bowl; and 34 the feed channel from the bowl to the nozzle 35 that projects into the passageway 3| so that fuel is drawn to and from the nozzle I by suction action, as well understood in the art.

The nozzle orifice 34 has communication with idler lets 88 through a channel 31, such jets being located adjacent to and one at each side of the throttle valve 12 when in closed position.

The novel feature consists in extending a relief passage 38 from the nozzle channel 34 to a vent is to the atmosphere, which vent is controlled by a normally closed valve 40. This valve operates in a chamber 4| and is yieldingly held by a spring 42 in position to close the communication between the passage 38 and vent 39 and is moved by suction action in the inner end portion of the chamber to open such communication. A channel 43 extends from the inner or suction end of the chamber 4| to the interior of the passageway 3i, and in the present instance, has a branch 44 opening into the passageway at the inlet side of the throttle valve, preferably through the most restricted portion of its venturi 45, and a branch 44 opening into the passageway at the outlet or engine side of the throttle valve. The rush of air or gaseous fuel through the passageway 3| when the engine is operating at high speeds is sumcient to draw the valve 40' inward against the tension of the spring 42 and open the vent 39 t0 the passage 38, the speed at which such opening occurs depending on the tension of the spring.

The nozzle passage 34 is thus relieved of suction action and the flow of fuel thereto. as well as to ,4 the idling lets it, is stopped when the engine reaches a predetermined speed.

By locating the passageway ends of the branches 44 and 46 above and below the throttle valve, as shown, the intake suction therethroush will be on a gradual slope which increases in direct relation with engine speed. In other words, the suction power in the line 43 will increase similar to a centrifugal governor as the speed increases While the use of both orifices 44 and 4B is preferable, the device will work fairly well with the orifice 44 omitted, but the vacuum would be much higher and would require a stronger suction device, spring arrangement, etc., to handle the system.

It is apparent that ineach illustrated form of the invention the fuel flow from the carburetor bowl to the discharge nozzle is stopped when the engine reaches a. predetermined speed, the stoppage being occasioned by relieving the suction action in the carburetor nozzle when the speed limit is reached. It is also apparent that in both of these forms of the invention, the suction action in the fuel supply passage to the engine is utilized to actuate a valve to effect the stoppage of the fuel flow to the carburetor nozzle when the engine reaches the predetermined speed. In each case, the engine is operating at full horsepower until the speed limit is reached, which is an important advantage.

Upon a stoppage of the fuel flow to and from the main and idler feed orifices, the fuel that had gone into the engine would all be burned and therewould be no fuel in the muffler to cause backfire or explosions. The engine would simply quit or slow down every time the operator tried to overspeed, the same as if he ran out of gasoline, but there would be no effect whatever on the power below the limit speed.

The device is simple and could be easily and quickly attached to any carburetor by merely adding, in the case of Fig. 1, the bleed line l5 into the carburetor and attaching the speed governor fittings thereto, or, in the case of Fig. 2, adding the bleed line 38 with the control valve 40 and the suction lines 43, 44, 46 to control the opening of such valve by suction from within the engine fuel feed passageway 3|. It would not be necessary to connect any rods to the throttle, or supply other parts, as is the case with other speed control governors of which I am aware.

I wish it understood that my invention is not limited to any specific construction, arrangement or form of the parts, as it is capable of numerous modifications and changes without departing from the spirit of the claims.

Having thus described my invention, what I claim as new and desire to secure by United'States Letters Patent is:

1. The combination with an internal combustion engine comprising a fuel feed passageway to the engine cylinders and a carburetor having a fuel supply source, a main discharge nozzle disposed in said' passageway, a channel through which fuel is drawn from the source to the nozzle by suction action therein occasioned by the rush of gases through said passageway, and a throttle in said passageway, of a vent channel leading to said nozzle channel from the atmosphere, and means normally closing said vent channel and operable to open it and vent the nozzle channel to stop the fuel flow therethrough when the engine reaches a predetermined open throttle speed.

2. The combination ascalled for in claim 1 wherein said means comprises a valve normally closing said vent channel to the atmosphere and movable by suction action to open such channel when the engine speed reaches a predetermined point.

3. The combination as called for in claim 1 wherein said means comprises a valve normally closing said vent channel to the atmosphere and a channel opening communication between said valve and said fuel feed passageway, whereby the rush of gases through said passageway creates a suction in said last channel to move the valve to an open position when a predetermined open throttle speed is reached by the engine.

4. The combination as called for in claim 1 wherein said means comprises a rotatable member driven by the engine and forming a part of said vent channel, and a valve carried by said member and operable by centrifugal action to open said channel to the atmosphere when the engine reaches a predetermined speed. 5. The combination with an internal combus- "tion engine having a fuel feed passageway to its cylinders and a carburetor having a main fuel feed channel for supplying fuel to'the passageway by suction action therein, and having a Jthrottle in the passagewayat the engine side of said channel, ofa vent channel leading to said feed channel from the atmosphere, and means normally closing said vent channel and operable to open it and vent said feed channel to stop the fuel flow therethrough when the throttle is open and a predetermined engine speed is reached.

6. The combination as called for in claim 5- wherein saidmeans comprises a valve normally closing said ventchannel to the atmosphere and movable by suction action to open such channel the engine.

as called for in claim 7,

a predetermined speed is reached by the en- 8. The combination wherein said fuel feed communication with the interior of the passagewoiy adjacent to and at both sides of the throttle va ve.

channel has supplemental movableto open the channel, and means forming 9. The combination with an internal combustion engine having a fuel feed passageway to its cylinders and a carburetor having a main nozzle opening into said passageway with'its channel in communication with the carburetor fuel supply whereby fuel is caused to flow through said channel and nozzle to the passageway by suction action in the latter, and a throttle in said passageway at the engine side of said nozzle, of means having a vent channel from saidnozzle channel to the atmosphere, and means normally closing said vent channel to the atmosphere and automatically operable to open the vent channel and relieve the suction in said nozzle channel to stop the flow of fuel to the. nozzle when the engine reaches a predetermined speed on open throttle. 10. The combination with aninternal combustion engine having a fuel feed passageway to its cylinders, andacarburetor having main and idling nozzle jets opening into said passageway and fuel feed channels thereto, whereby suction in said jets causes fuel to flow thereto from a'supply source, of a vent channel leading from said feed channels to the atmosphere to stop the flow of fuel therethrough when the vent channel is open,

and means normally closing said vent channel and operable to open it and vent said feed channels to stop the fuel flow therethrough when a predetermined engine speed is reached.

11. The combination with an internal combustionengine having a fuel feed passageway to its cylinders and a carburetor having a main fuel feed channel for supplying fuel to the passageway. by suction action therein and having a throttle in the passageway at the engine sideof said channel, of a vent channel leading to said feed channel from the atmosphere, means normally atmosphere when the closing said vent channel and operable to open it and vent said feed channel to stop the fuel flow therethrough when the throttle is open and a predetermined engine speed is reached, said means comprising a rotatable member driven by the engine and forming a part of said vent channel, and a valve carried by said member and operable by centrifugal action to open said channel to the engine reaches a predeter MARION MALLQRY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED s'ra'rns PATENTS mined speed.

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