US 2152028 A
Description (OCR text may contain errors)
March 28, 1939. H. D. CHURCH 2,152,028
- 1 FUEL ECONOMIZER Filed Nov. 6, 1937 INVENTOR. HAROLD D. CHURCH.
Patented an 2%, i3
FUEL ECUNQWWR Harold D.v Church, Cleveland Heights, lililiio, as-
signor of one-half to Raymond M. Anderson,
Application November 6, 1937, Serial No. 173,221
This invention relates broadly to hydro-carbon engines and more specifically to mechanism for controlling the ratio of air and gasoline in the fuel mixture during part load operation of such engines.
In the development of the internal combustion engine various means have been used from time to time to improve the fuel economy thereof. These efforts contemplated generally mechanism for modification of the air gas ratio after the engine had been started, instrumentalities for the admission of a constant'suppplemental supply of air to the mixture after atomization of the fuel and various spray jet operating devices for leaning the mixture concomitant with the engine road speed loads.
Although gains in economy have been attributed to the use of the foregoing devices, such gain has been realized only at the sacrifice of engine response during the initial adjustment of the throttle or the lack of flexibility of the engine under part load throttle.
The mechanism comprising the present invention embodies a valve controlled by a vacuum responsive device coupled with the engine intake manifold and organized for automatic modification of the air gas ratio in proportion to the road speed loads of the engine. With such mechanism a fuel mixture of suitable combustability for uniform performance will be delivered to the engine irrespective of the load and speed demands thereon and without loss of engine response or flexibility of performance.
One of the objects of the invention is to provide a valve actuating mechanism for regulating the air-gas ratio of the fuel mixture proportional to the road speed load requirements of the engine.
Another object of the invention is to provide mechanism for automatically slightly enrichening or leaning the mixture momentarily under slight opening or closing of the throttle within a predetermined range of road load operation.
Another object of the invention is to provide mechanism for increasing and automatically cutting off the auxiliary air supply when manifold depression falls below a predetermined minimum regardless of speed.
Another object of the invention is to provide mechanism for reducing the engine pumping losses and increasing the part load compression pressure, thereby increasing the throttle thermal efficiency of the engine.
Other objects and advantages more or less ancillary of the foregoing and the manner in which all he various objects are realized will appear in the following description which, considered in connection with the accompanying drawing, sets forth the preferred embodiment of the invention.
Referring to the drawing in which the preferred 5 embodiment of the invention is illustrated:
Fig. 1 is an elevational view of a fragmentary portion of an internal combustion engine including a carburetor of thedown draft type and the automatic air valve constituting the present inlo illustrated herein, may be of the down draft type. 20
The engine is provided with an air cleaner it connected in the" customary manner to the carburetor it.
The carburetor throttle tube i2 is formed with a boss having an aperture it therein which is 25 disposed in juxtapositon to throttle plate li when adjusted in engine idling position and on the carburetor side thereof. The boss i5 is drilled and tapped for the reception of a pipe fitting l8 adapted to support a tube it to convey the pres- 30 sure at aperture it to the automatic air valve 28.
The valve 2t may'be incorporated within the carburetor or intake manifold as a unitary part thereof or may be formed, as shown, as an accessory for installation between the carburetor tube 35 and manifold of an engine. In detail the valve comprises a plate 20 having an opening in the central portion thereof equal to the bore of the intake manifold. The plate is disposed intermediate the companion flanges of the carburetor 40 and intake manifold it, gaskets 22 being provided in the assembly to facilitate a fluid-tight connection. The central portion of the plate is formed with a boss 26 which is bored for the reception of a piston 25 machined for a snug 45 reciprocating fit within the bore or cylinder 23. The inner end of the cylinder 23 is provided with a duct 26 in fluid. communication with the opening in the central portion of the flange 2i and coaxially aligned with the bore of the cylinder. 50
The piston 25 is formed with a reduced end portion 21, which is tapered to form a conical valve 28 adapted for seated engagement upon the wall of the cylinder which defines the throat of the duct 26. The free end of the cylinder is threaded for the reception of a cap 29 having a pipe fitting 30 in the end wall thereof for the support of the tube l9. Within the recessed portion of the piston there is a helical spring 3| compressively engaged with the cap 29 and adapted to urge the cone valve 28 upon its seat in the throat of the duct 26. The cylinder 24 is formed with a boss 32 having a bore therein for the support of a conduit 33 which provides fluid communication from the cylinder to the air cleaner M.
The fitting 30 is preferably formed with bore 34 having a plug 35 therein which is constructed with a reduced end portion 36 for the support of a helical spring 31. The spring is engaged with a disc valve 38 seated upon the end wall of the bore 34 and restricted from excessive longitudinal movement by the end of the plug 35. The periphery of the valve is toothed or serrated to facilitate the free circulation of air through the canal 39 and the communicating bores 40 and 4| in the plug 35 so that the piston 25 will seat immediately upon reduction of the subatmospheric pressure in the line IS. The centerpf the disc is provided with an aperture 42 of restricted area so that sudden movement of the piston 25 will be retarded upon the initial application of high subatmospheric pressure through the tube l9. Thus when the throttle valve is adjusted to a position when a high subatmospheric pressure is obtained in the tube is, the cone valve will. be lifted slowly from its seat but when the subatmospheric pressure falls to the point where the spring 3! outweighs the pressure the piston 25 will "slide inwardly and impose a vacuum upon the disc which in turn overcomes the spring 31, and facilitates the rapid closure of the cone valve 28.
The spring 3| is constructed to seat the valve 28 when the throttle H is adjusted to its closed position as when the engine is idling but will be overcome by the subatmospheric pressure in the zone of the aperture l5 in the throttle tube during the early opening of the throttle plate I1. In order to maintain a combustible mixture throughout the operative cycle of the valve 23 the tapered end thereof is calibrated against the area of the throttle opening; the spring 3| and the pressure in. the carburetor throttle tube to effect an air gas ratio of the desired proportion, at throttle openings corresponding to average road load mixture volume requirements. Obviously the size, location and shape of the aperture I6 can be arranged in respect to the throttle plate l l to effect the desired pressure in the tube I 9 through any predetermined road speed range. Thus it will be seen that Huringthe operation of the engine where the throttle valve is adjusted at less than wide open position, the position of the piston 23 will be altered by changes in throttle setting or by changes in the engine speed and load. Since in ordinary operating conditions of an automotive vehicle the power requirements are being constantly altered by variations in rolling resistance and/or wind resistance, the automatic reciprocation of the piston within the predetermined range of operation or the so called hunting action, the valve tends, at all times, to supply the engine with the leanest mixture which will satisfy the instantaneous road load requirements. As the valve constantly changes its position during normal road operation, the area of valve opening will constantly meter the admission of supplemental air so that the most economic air gas ratio to the road speed may be realized.
It willbe apparent from the foregoing that as the valve 28 is opened supplemental air will be admitted through the duct 26 and commingle with the fuel mixture in the intake manifold ll, thereby diluting the mixture, atomizing the charge to a higher degree and in addition reducing the engine pumping losses.
Although the foregoing description is necessarily of a detailed character, in order that the invention may be completely set forth, it is to be understood that the specific terminology is not intended to be restrictive or confining, and that various rearrangements of parts and modifications of detail may be resorted to without departing from the scope or spirit of the invention as herein claimed.
1. In an internal combustion engine embodying an intake pipe having a throttle plate therein, means for the dilution of the fuel mixture in said intake pipe, comprising a conduit connected with said intake pipe on the carburetor side of the throttle plate when the throttle is closed and substantially adjacent the edgethereoi' which passes thereby as the throttle is opened, a pres sure responsive mechanism to which said conduit leads, a valve operatively connected with said pressure responsive mechanism and interposed in an opening in said intake pipe on the engine side of said throttle plate, said valve being calibrated to vary the volume of air admitted therethrough relative to the sub-atmospheric pressure in said conduit.
2. In an internal combustion engine embodying an intake pipe having a throttle therein, a
7 pressure responsive mechanism, a fluid connection between the pressure responsive mechanism and said intake pipe, said connection entering said intake pipe through an orifice disposed on the carburetor side of said throttle close to the peripheral edge thereof when the throttle is closed and disposed so that said throttle passes thereby as it is opened, an air valve operatively connected with said pressure responsive mechanism and connected with said intake pipe on the engine side of said throttle, to admit auxiliary air into said .intakepipe, said valve being calibrated to vary the admission of air therethrough substantially proportional to variations in the subatmospheric pressure in said fluid connection due to variations in engine speed for certain throttle positions. I
3. In an internal combustion engine embodying an intake pipe having a throttle therein, meansfor the automatic control of the fuel mixture ratio comprising a pressure responsive mechanism, a fluid connection between the pressure responsive mechanism and said intake pipe, said connection entering said intake pipe through an orifice disposed on the carburetor side of said throttle adjacent the peripheral edge thereof when said throttle is adusted in engine idling position and so disposed as to be gradually brought into the zone of sub-atmospheric pressure as the throttle is opened, an air valve operatlvely con nected with said pressure responsive mechanism and communicating with said intake pipe on the engine side of said throttle, said valve and said pressure responsive mechanism automatically increasing the admission of air to the intake pipe as the throttle is moved from engine idling position to a predetermined-opening and automatically decreasing the admission of air to the intake pipe when the throttle is moved beyond said predetermined opening.
4. In an internal combustion engine embodying an intake pipe having a throttle plate therein, means for the automatic admission of supplementai air into the fuel mixture comprising, a valve for admitting air into the intake pipe on the engine side of said throttle plate, a pressure responsive mechanism operatively connected with said valve, a member having a fluid passage therein communicating with said pressure responsive mechanism and with the intake pipe through an orifice on the carburetor side of the throttle plate when the throttle is closed and in intimate relation with the portion of the plate which passes thereby as the throttle plate is moved toward its open position, said pressure responsive mechanism and said valve being calibrated relative the sub-atmospheric pressure in said fluid passage to admit air into said intake pipe proportional the engine load and speed within a predetermined range of throttle positions.
5. In an internal combustion engine having an intake pipe and a throttle therein, mechanism for the automatic admission of supplemental air to the fuel mixture in said intake pipe comprising a fluid opened valve, a valve housing therefor having a port thereincommunicating with the atmosphere and a second port in said housing leading to said intake pipe on the engine side of said throttle, a. spring in said housing normally urging said valve to close the second named port, a conduit leading from said valve as housing to said intake pipe for the transmission of sub-atmospheric pressure for operating said valve and communicating therewith through an opening on the carburetor side of the throttle, and disposed in the intake pipe so that the throttle passes thereby as said throttle is opened, said valve being formed to admit a volume of air proportional the volume of fuel mixture passing v said orifice being juxtaposed to said throttle and is opened, said valve being formed to effect predetermined progressive opening areas which are proportional to the progressive opening areas of said throttle within the range of engine speed determined by the shape and location of said orifice.
7. In an internal combustion engine having a throttle plate in the intake pipe, mechanism for controlling the admission of air to the fuel mixture in the intake pipe, comprising a. cylinder, a
piston therein, a valve plunger on said piston, said cylinder having a port therein adjacent said plunger and communicating with the atmosphere anda second port in fluid communication with said intake pipe on the engine side of said throttle plate, the opening of said second named port being operatively controlled by said plunger for the admission of atmospheric air to said intake pipe, a conduit connecting the portion of the cylinder rearward of said piston with said intake pipe and having fluid communication therewith through an orifice on the carburetor side of the throttle plate injuxtaposition with the seat therefor when the throttle is closed, said orifice being disposed so that the throttle plate passes thereby as the throttle is progressively opened within a predetermined range of engine opem tion, whereby said orifice is subjected progressively to the influence of sub-atmospheric pressure in the intake pipe and to variations of sub-' atmospheric pressure independent of throttle movement caused by load variations imposed upon the engine.
8. In an internal combustion engine embodying an intake pipe having a throttle plate therein, mechanism for the automatic control of the ratio of air to gasoline in the fuel mixture, comprising a valve for the admission of air to the intake pipe on the engine side of said throttle plate, a pressure responsive m connected therewith, a conduit connecting said pressure responsive mechanism with the intake pipe through an orifice therein, said orifice being located in relation to said throttle plate to admit atmospheric pressure in said conduit when the throttle is in idling position, and located so that the throttle plate passes thereby as the throttle is opened and circumferentially located relative the edge of said throttle plate when in its closed position to effect maximum sub-atmospheric pressure in said conduit at a predetermined part throttle position.