Abstract:
A four cylinder engine including two outer cylinders valved to operate on a four cycle basis, the outer two cylinders being movable together in opposite directions than the direction of movement together of the two inner cylinders. The two inner cylinders valved to operate on a two-cycle basis. The four cylinders having fuel injectors for injecting an amount of fuel in an associated cylinder so as to cause a self-ignited power event to occur therein during each cycle. The engine, when embodied in a vehicle having a battery energized computer and manually operated accelerator pedal being selectively operated in three power levels: (1) a minimum fuel mode (2) an intermediate fuel mode and (3) a maximum fuel mode. (1) Enabling a two-third fuel saving (two injections out of a possible six) when in minimum fuel mode and (2) a one-third saving fuel (four injections out of a possible six) when in the intermediate mode. The two inner cylinders operate on the fuel sharing principles of the &#39;769 patent when in the intermediate mode.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Patent Application No. 62/325,218 filed Apr. 20, 2016, the entire content of which is incorporated herein by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to internal combustion engines and particularly to engines suitable to move vehicles with improved fuel economy and specifically improved MPG (miles per gallon). 
       SUMMARY OF THE INVENTION 
       [0003]    The present invention utilizes fuel saving principles disclosed in U.S. Pat. No. 8,443,769, the disclosure of which is hereby incorporated by reference into the present disclosure. The engine configurations disclosed in the &#39;769 patent are particularly suited for heavy truck operation. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0004]    The present invention is particularly concerned with the provision of a four cylinder engine configuration embodying the fuel saving principles of the &#39;769 patent, that may be better suited for cars and light-weight trucks. In accordance with the principles of the present invention, the four cylinder engine includes four piston and cylinder assemblies mounted in a frame structure in a row formation so that the outer two assemblies move together and in opposite directions to the two inner assemblies moving together. While the present invention has this characteristic in common with conventional four cylinder engines, it differs basically in that the outer assemblies, rather than being the same as the inner assemblies, are different from the inner assemblies. Specifically, the outer assemblies are valved to operate on a four-cycle basis while the inner assemblies are valved to operate on a two-cycle basis. The arrangement achieves one four-cycle drive stroke and two simultaneous two cycle drive strokes during each crankshaft rotation so that during a two revolution cycle involving four strokes of each cylinder, the drive stroke pattern which takes place includes the following in sequence: (1) one of the outer four cycle assemblies, (2) both of the inner two cycle assemblies together, (3) the other outer four cycle assembly, and (4) both of the inner two cycle assemblies together. Since the two inner two cycle assemblies are always operated together, they are subject to being selectively injected in one of three different ways: (1) both inner two cycle assemblies receive an injection directly, (2) both inner two cycle assemblies are skipped and receive no injection and (3) only one of the two inner two cycle assemblies receives an injection directly with the other skipped cylinder sharing a power event therewith in accordance with the teachings of the &#39;769 patent. 
         [0005]    With these options available, the engine when combined in a vehicle with an accelerator pedal, and computer control can be operated (1) in a minimum mode range corresponding to an initial range of pedal depression wherein the inner two cycle assemblies are skipped and only the two outer assemblies have a power event during each cycle (two out of a possible six are injected or a two-third saving of maximum fuel) (2) in an intermediate mode range corresponding to an intermediate range of movement of the accelerator pedal wherein one of the two inner assemblies receives an injection during each cycle so that the two share power events and the two outer assemblies have a power event (four out of a possible six are injected or a one-third saving of fuel) and (3) in a maximum mode range corresponding with a final range of pedal movement wherein all of the assemblies receive an amount of fuel by injection during each cycle resulting in each assembly having its own power event (six out of six—no fuel saving). 
         [0006]    The computer may be constructed and arranged to vary the amount of fuel injected so that there is a smooth transmission from one range to the next. Thus the total amount of fuel injected at the end of the minimum range is the same as the total amount of fuel injected at the start of the intermediate range and so forth. 
         [0007]    Other objects, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a vertical sectional view taken along the plane of the axes of the four cylinders embodied in the engine of the present invention. 
           [0009]      FIG. 2  is a schematic view showing the gaseous flow circuit for the engine shown in  FIG. 1 . 
           [0010]      FIG. 3  is a schematic view of the engine shown in  FIG. 1  embodied in an automotive vehicle having a computer and accelerator pedal for controlling the fuel injectors of the four assemblies, containing graphical illustrations of the operation when (A) in a minimum fuel mode (B) in an intermediate fuel mode and (C) in a maximum fuel mode. 
       
    
    
     DETAILED DESCRIPTION 
       [0011]    Referring now more particularly to  FIG. 1 , there is shown therein an internal combustion engine, generally indicated at  210 , which embodies the principles of the present invention. The engine  210  includes a frame structure, generally indicated at  212 , consisting of a lower pan section  213 , an intermediate block section  214  detachably fixed on the pan section  213  and a head section  216  detachably fixed on the block section  214 . 
         [0012]    Formed in the block section  214  are four cylinders  218 A,  218 B,  218 C and  218 D disposed in a row formation. The cylinders  218 A-D forms parts of conventional piston and cylinder assemblies which also include pistons  220 A,  220 B,  220 C and  220 D mounted in their respective cylinders for movement through successive strokes toward and away from the head section  216 . The stroke movements are accomplished by piston rods  222 A,  222 B,  222 C and  222 D pivotally connected at one of their ends to the associated piston  220  and at their opposite ends to a crankshaft  224  through crank arm portions  226 A,  226 B,  226 C and  226 D, respectively formed on the crankshaft  224 . The crankshaft  224  includes bearing portions  228  journaled in bearings  230  fixed between the pan section  213  and block section  214 . 
         [0013]    The two outer cylinders  218 A and  218 D are valved differently from the two inner cylinders  218 B and  218 C. The valving as shown includes two poppet valves in the upper end of each cylinder. Each poppet valves, which are to the left in each cylinder, is an inlet valve  240 A,  240 B,  240 C and  240 D, respectively, spring biased, as by springs  139 , to seal on valve seats defining inlet openings  234 A,  234 B,  234 C and  234 D, respectively, for the cylinders. 
         [0014]    The two right hand poppet valves of the inner two cylinders  218 B and  218 C referenced are also designated by the characters  240 B and  240 C, since they also serve as inlet valves for the two inner cylinders  218 B and  218 C. The two inner cylinders operate on a two cycle basis in which each cycle includes an upward compression stroke and a downward power stroke (also called the drive stroke). Toward the end of the downward power stroke, the pistons  220 B and  220 C downwardly pass and move into communication with a series of annularly spaced outlet openings  286 B and  286 C, respectively, formed in the wall of the cylinders  218 B and  218 C. When the outlet openings  286 B and  286 C are reached, the valves  240 B and  240 C are cammed to open by suitable cams on a camshaft  288  journaled on the head section  216 . The camshaft  288  is connected to the crankshaft  226  by a motion transmitting assembly  290  which causes the camshaft  288  to rotate twice as fast as the crankshaft  224 . 
         [0015]    Referring now more particularly to  FIG. 2 , there is shown therein a flow diagram which enables an exchange of gases to take place within cylinders  220 B and  220 C when the inlet valves  240 B and  240 C are open and the pistons  220 B and  220 C have passed the outlet openings  286 B and  286 C. 
         [0016]    As shown in  FIG. 2 , the gas entering the inlets  234 B and  234 C through open valves  240 B and  240 C comes from a supply of air under pressure created in the outlet of an air pump  292  forming an integral part of a turbocharger, generally indicated at  294 . The air pump  292  draws air from an inlet  296  through an air filter  298 , and pumps it through a heat exchanger  300  and into an inlet manifold  302 . The air under pressure in the inlet manifold  302  is communicated with the inlets  234 B and  234 C by passages  282 B and  282 C. 
         [0017]    The inlet manifold  302  is also communicated with the inlets  234 A and  234 D leading to the two outer cylinders  218 A and  218 D under the control of inlet poppet valves  240 A and  240 D. The two outer cylinders  218 A and  218 D are also controlled to operate on a four cycle basis by the conjunctive operation of two right hand exhaust or outlet poppet valves  284 A and  284 D respectively, spring biased to seal on outlet valve seats  282 A and  282 D respectively defining outlet openings for the two outer cylinders  218 A and  218 D. The four stroke cycle operation accomplishes four consecutive events in four consecutive strokes: (1) an inlet event (2) a compression event (3) a power event and (4) an exhaust or outlet event. The inlet and outlet valves  240 A-D and  284 A-D are closed during all the events except the inlet valves  240 A and  240 D are open during the inlet event and the outlet valves  284 A and  284 D are open during the outlet event. 
         [0018]    Referring again to  FIG. 2 , the outlet openings  286 B and  286 C and the outlets  284 A and  284 D are all communicated with an outlet manifold  304  which, in turn, is communicated as by conduit  306  to a turbine  308  forming a part of the turbocharger  294 . As is usual, the pressure from outlet manifold  304  impinges upon the turbine  308  to cause it to rotate which, in turn, causes the connected pump  292  to rotate and pressurize the drawn-in air through inlet  296  and air filter  298 . 
         [0019]    The diagrammatic view of  FIG. 2  also illustrates schematically the fuel injectors  252 A,  252 B,  252 C and  252 D for the cylinders  218 A-D respectively. The injectors  252  are communicated with a fuel line  310  containing fuel under pressure created by a pump and fuel source system. Each injector  252  includes an outlet valve which is spring biased closed and opened by the energization of a solenoid  314 . 
         [0020]    The diagrammatic view of  FIG. 2  also indicates components of an automotive vehicle within which the engine  210  is suitably mounted. Thus, the vehicle includes a battery  316  (or other electrical power source, such as an alternator) by lead  320  capable of selectively controlling the energizations of the solenoids as by leads  322 . 
         [0021]    Referring now more particularly to  FIG. 3 , there is shown therein three charts representing three selective operations of the computer  318  in controlling the power level and speed of the engine  210 . Each chart indicates the event occurring in each of the four cylinders during each piston stroke of 180° of crankshaft movement for a full cycle of 720°. 
         [0022]    The power level variations are obtained by maintaining the injection of fuel into the two outer cylinders a single constant injection in each outer cylinder  218 A or  218 D during each cycle and varying the injection of fuel into the two inner cylinders  218 B and  218 C. 
         [0023]    The fuel variation is controlled by the computer  318  in accordance with the position of an accelerator pedal  320  sensed by a sensor  322  connected to the computer  318  by lead  324 . The variation also may be automatically controlled based on input of a cruise control system. 
         [0024]    Chart A shown in  FIG. 3A  chart represents a minimum power level which is selected by the computer when the pedal  320  is in its fully extended position or a first third range of depressed movement therefrom. In this minimum power level mode, the computer is selectively operable to skip the injection to both the two inner cylinders  218 B and  218 C, so that during every stroke when the two outer cylinders  218 A and  218 D do not have a self-ignited firing event one of the outer cylinders has a firing event consisting of piston movement under compression pressure. 
         [0025]    Chart B represents an intermediate level of power. This mode is chosen by the computer  318  when it senses that the pedal  320  has been depressed to move through an intermediate one third range of movement (or a similar intermediate position between a minimum and maximum). In this mode, the computer is operable to inject a charge of fuel into only one of the two inner cylinders  218 B and  218 C while the other one is skipped. In this mode, the one inner cylinder which receives the injection undergoes a self-ignited power event which is shared with the other inner cylinder by a passage  256  extending between them in accordance with the fuel saving principles of the &#39;769 patent. The inner cylinders may alternate between receiving the fuel injection and receiving the shared pressure from the other as shown. Consequently, in the intermediate mode, during every other stroke when the two outer cylinder  218 A and  218 D do not have a self-ignited firing event, the two inner cylinders have a shared firing event. 
         [0026]    Chart C represents a maximum power or speed level. This mode is chosen by the computer  318  when it senses that the pedal  320  has been depressed to move through a final one third range of movement. In this mode, the computer  318  is selectively operable to inject a charge of fuel in both inner cylinder  218 B and  218 C so that they have simultaneous self-ignited power events. Consequently, in the maximum power level mode, every other stroke when the two outer cylinders do not have a self-ignited power event, the two inner cylinders  218 B and  218 C have simultaneous self-ignited power strokes. 
         [0027]    It can be seen that any time the engine  210  is moving the vehicle while the vehicle is coasting with the operators foot off of the pedal  320  or while the operator is braking the vehicle, the computer  318  chooses the low power level resulting in only 2 injections out of a possible six per cycle taking place for up to ⅔rds fuel saving. This minimum use of fuel continues as long as the pedal  300  is depressed within the first one third range of movement. 
         [0028]    When acceleration beyond coasting is required, the operator depresses the pedal through the second one third range of movement. In this mode the sharing procedure takes place and there are 4 injections out of a possible 6 that take place (up to a ⅓ fuel saving). This mode is most likely to be in use most of the time during a typical truck haul. 
         [0029]    The maximum power level which is shown in Chart C is not expected to be used except those situations when maximum power is required. There is no fuel saving in this mode but it is to be noted that the use of two cycle operation in the two inner cylinders  218 B and  218 C increases the maximum power of the engine  210  by 50% as compared with a conventional 4 cylinder four stroke engine, which added power on occasion is highly desirable to have. 
         [0030]    The present engine  210  is advantageous when compared with a 4 cylinder/4 stroke engine capable of skipping two cylinders, not only in providing unavailable power even though both use only two injections when coasting or braking. The conventional engine uses four injections most of the time, while the present engine uses 4 injections in intermediate mode. But the power sharing event between the inner piston/cylinders increases the power available at any given fuel amount so that an estimated saving of 30% is obtained over conventional operation. 
         [0031]    Finally, it will be understood that the computer  318  is constructed and arranged to vary the amount of fuel injected so that there is a smooth transmission from one range to the next. For example, the total amount of fuel injected at all fuel-receiving cylinders at the end of the minimum range may be the same amount of fuel injected at the start of the intermediate range and so forth. 
         [0032]    It is important to note that while the present engine is constructionally similar to a conventional four cylinder engine, it is capable of generating power from six injections each cycle rather than just four. Consequentially, the present engine offers a 50% increase in power as compared with a conventional four cylinder engine. In the minimum fuel mode of the present engine it uses only 33⅓ of the maximum. Even so, this 66⅔% saving achieved by 2 injections in the two outer cycle assemblies per cycle is equal to the 50% saving in a conventional 4 cylinder engine capable of skipping 2 cylinders. The 66⅔% saving is achieved any time during operation of the vehicle when the operator takes his foot off the accelerator to brake or let up on it when coasting. 
         [0033]    The conventional 4 cylinder engine capable of skipping 2 cylinders must operate on all four cylinders anytime the accelerator pedal is depressed to maintain the speed or increase the speed of the vehicle, which is the situation during a large part of the time the vehicle is moving. The present engine can operate in intermediate mode for this more frequent operation saving 33⅓ of the maximum fuel that can be used. 
         [0034]    In this intermediate mode, 4 injections take place, the same number as in a conventional skipping 4 cylinder engine. However, because of the sharing of power events, a lesser amount of fuel is needed in the present engine to reach the same power level achieved in the conventional skipping engine. This difference results in an estimated 30% fuel saving in comparison to conventional anytime the present engine is operating in the more frequent intermediate mode. 
         [0035]    There is no fuel saving when operating the present engine in maximum fuel mode but the conventional cylinder skipping engine is incapable of operating at this power level so it is rarely used in the operation of the present engine, but nice to have when the rare occasion arises.