US2545709A

US2545709A - Combination governor and ignition system for internal-combustion engines

Info

Publication number: US2545709A
Application number: US50718A
Authority: US
Inventors: Marion L Smitley
Original assignee: Individual
Current assignee: Individual
Priority date: 1948-09-23
Filing date: 1948-09-23
Publication date: 1951-03-20
Anticipated expiration: 1968-03-20

Description

March 20, 1951 SMITLEY COMBINATION G0 ERNOR AND IGNITION SYSTEM FOR INTERNAL-COMBUSTION ENGINES Filed Sept. 23. 1948 INVNTOR.

BY MM Patented Mar. 20, 1951 COMBINATION GOVERNOR AND IGNITION.

SYSTEM FOR INTERNAL-COMBUSTION ENGINES Marion L. Smitley, Detroit, Mich., assignor to George M. Holley and Earl Holley Application September 23, 1948, Serial No. 50,718

1 Claim. 1

The object of this invention istocontrol the spark advance when using a sandwich type. governor on an automotive engine with a well known pressure (suction) controlled ignition system. In a-sandv/ich governor the governor throttle is mounted downstream of the main throttle-in a housing-which is the sandwich between the inlet manifold and the carburetor. When such a governor acts, the manual throttle being located upstream of the governor throttle and being wide open, there is a danger that the spark will not be correctly controlled for all conditions and that the calibration established for the carburetor, without the sandwich governor, will be lost.

The figure shows diagrammatically the preferred formof my. invention.

In the figure air enters at l6 and flows through a venturi l2, past a fuel nozzle |.4 fed from a float chamber, not shown. A restriction I3 is located in the throat of the venturi l2 and is connected through a pipe with a chamber 22 which contains a spring 24 and a diaphragm 28 which forms the moving wall of chamber 22 and 28 and is connected through a rod 30 with a spark advance device 34. An increase in suction in chamber 22 advances the spark in the well known manner without the use of the conventional centrifugal weights.

A passage 36 is connected to the restriction l8 and also through a restriction 38 to the mixture outlet at a point located just above the lip of the throttle 42 when the throttle 42 is in its idling position. This gives the desired retarded spark for idle and an immediate advance when the throttle is first opened away from idle.

A governor throttle 44 is connected to a lever which is connected to a governor, not shown. A passage 50 is normally located above the governor throttle when this throttle is in control and is connected to a chamber 54. For reasons of economy and space the sandwich containing the throttle 44 is made as thin as possible, otherwise passage 50 would be located at a higher level.

A second moving wall or piston 56 is pushed to the left by a compression spring 60 when pressure in passage equals pressure in passage 56, that is, when the governor throttle is more than one-half way.

A restricted passage 64, in the piston 56, forms the connection between the passages 36 and 14 with a passage 16, which passage is connected to the mixture outlet downstream of the governor throttle 44. An annular port 12, in the piston 56,

communicates withpthe restriction 64 and also with a passage 14 when the piston is drawn to the right by the suction in the passage 10 into the position in which it is shown, which is. the position in which the governor is acting to control the speed of the engine by the throttle 44, the throttle 42 being then wide open. Under these circumstances, the engine suction, acting through restriction 64, is strong enough to create a suction in chamber 22 to advance the spark in spite ofthe air leaks at restrictions I8 and 38.

At certain positions. of the throttle 44 the restriction 64 is cut off from passage 14 and an undesirably low suction will exist in chamber 54 and not enough suction in chamber 22'. To avoid this a passage 5|. can be usedin. place of or in conjunction with passage 50. Passage 5| islocated outside of the zone influenced by governor throttle 44.

If this device is sold as an accessory tov existing carburetors it is impossible commercially to drill holes such as 5| and 14 in the flange of a carburetor. In that event 14 is replaced with a tube and a T joint made with pipe 20, and only passage could be used. Theoretically passage 5| is superior to passage 50. Actually it would make little difference as once the governor acts the throttle 44 closes to a position which opens the passage 14 to the restriction 64 by admitting substantially atmospheric pressure to chamber 54.

Operation At low speeds when the governor throttle 44 is wide open and the throttle 42 partly open, the suction in chamber 22 follows the increase in suction below the throttle 42 through the driving range and advances the spark by the suction transmitted through the restriction 3B in the well known manner of operation for this type of ignition.

- During wide open operation of throttle 42 (throttle 44 being also wide open) the suction in chamber 22 follows the speed and advances the spark by reason of the depression in the venturi transmitted through the restriction l8 to the chamber 22 in the well known manner. The flow through restriction 38 then acts to slightly reduce Venturi suction.

During governor operation the throttle 44 closes and suction, to the right of piston 56, placesrestriction 64 in communication with passages |43620 and chamber 22 as shown in the drawing. Restriction 64 overcomes the effect of both restrictions l8 and 38. Hence, the spark is advanced as the throttle 44 closes in response to governor action exactly as it was advanced when the governor was not in action and throttle 42 controlled the speed. The suction in chamber 22, as before, advances the spark.

When both throttles 42 and 44 are wide open the piston 56 again shuts off all communication between passage 10, 64 and 12, which is now substantially at atmospheric pressure, and passages 1436-30 and chamber 22.

Hence, with this invention there is no interference with the wide open control of the spark advance and the suction at [8 is only reduced, as before, by the small quantity of air bled through restriction 38 at practically atmospheric pressure (at lowest engine speed). Hence, the original calibration is satisfactory in spite of the governor. If air were to be introduced also through restriction 64 then the calibration of the ignition device for wide open operation would be quite in error before the governor acted to check the speed. This would cause a serious loss in torque.

The size of restriction 64 is selected so that the spark responds to the suction in passage 70 exactly as the spark responds to the suction in mixture outlet 40 when the throttle 44 is open and throttle 42 controls.

- When the governor throttle as is wide open the throttle 42 controls the spark through the restriction 38 and again the restriction E l, being closed, does not interfere with the advance as then the pressure in passages 50 and it are equal so that the spring 60 prevails and again the restriction 64 will not introduce any disturbing elements into the automatic spark advance control.

What I claim is:

An internal combustion engine in combination, an air intake to said engine, a venturi therein, a main air outlet passage from said venturi, a first throttle therein, a second throttle downstream therefrom adapted to be connected to an automatic governor, an ignition timing device for said engine, first yieldable means for retarding the spark, vacuum operated means for advancing the spark in said engine by overcoming said first yieldable means comprising a suction chamber having a first moving wall connected to said timing device, a first restricted passage connected to the throat of the venturi and to the chamber, a second restricted passage connected to the chamber and to the outlet passage on the engine side of said first throttle when said first throttle is first opened to operate the engine, a third restricted passage connected to the vacuum operated means and to the engine side of said second throttle, a valve in said third passage, a second moving wall connected to said valve, second yieldable means engaging with said wall to close said valve, a second chamber associated with said second moving wall and connected to the main outlet passage on the atmospheric side of said second throttle when said second throttle acts to control the speed, a third chamber on the other side of said second moving wall, a passage connecting said third chamber to the outlet from said main outlet passage on the engine suction side of said second throttle, the difference in pressure between second and third chambers associated with the second moving wall opposing the second yieldable means so as to open the restriction in said third passage when the second throttle acts to govern the speed of the engine so that the governor simultaneously throttles the flow of air through the venturi and advances the spark.

MARION L. SMI'ILEY.

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

UNITED STATES PATENTS Number Name Date 2,039,396 Darnell et al May 5, 1936 2,128,363 Jennings, Jr. Aug. 30, 1938 2,200,043 Sarnes May 7, 1940 2,377,566 Mallory June 5, 1945