US1868753A - Engine - Google Patents

Description

H. M. LEONARD 1,868,753

E'NGINE `July 26, 1932.

Filed June 5, 1926 HOWARD MLEONARD ATTORNEY Patented July 26, l 1932 UNITED STATES ylne'raNT OFFICEv HOWARD M. LEONARD, OF SOUTH BEND, INDIANA, ASSIGNOR, BY MESNE ASSIGNMENTS, TO BENDIX AVIATION CORPORATION, A CORPORATION OF DELAWARE ENGINE Application' filed llunel 3, 1926. Serial No. 113,361.

- bodied in a small high speed two-cycle engine of this type having a novel fuel pump immediately adjacent the engine cylinder.

@ fuel accurately as Athe successive charges arey fed to the pump. Attempts have been made ln some previous engines of this character in which the fuel is injected by a plunger type pump adjacent the engine cylinder, dificulty has been experienced in metering the to meter the fuel with a needle v alve which is reciprocated to feed the successive charges of fuel but this arrangement is undesirable in that the delicate needle valve is not suiliciently durable to withstand the constant pounding as it opens and closes during each cycle of the engine. Other arrangements include a needle valve-which serves to meter the fuel, with a. separate movable valve for controlling the ieed-ing'oi the fuel to the pump,

and while this arrangement can be made to operate satisfactorily it requires two sets of valve parts for cooperation with the pump. The present invention has for its object to provide a simple valve mechanism combined in a novel mann'er with vthe pump so that it will accurately meter extremely small quantities of fuel and at the same time serve to feed the charges of fuel to the pump` and which at the same time is extremely simple anddurable. ln one desirable arrangement the valve includes a disk or di slr-like member at the end oi the pump cylinder, and preferably opposite the end of the pump plunger, and which has an'opening which is brought by oscillation ot the valve periodically into and out of registry with an opening in the valve seat. ln the arrangement shown inthe drawings. the valve is mounted in a separate head projecting into an opening in the cylinder head of the engine and seating against the end of the sleeve forming the pump cylinder.

The above and other objects and Jfeatures of the invention, including various novel combinations of parts and desirable particular constructions, will be apparent from the following description. of one illustrative enibodiment shown in the accompanying drawing, in which:

Figure 1is avertical section throughthe engine cylinder and through the fuel-injectine pump;

F'gure 2 is a partial horizontal section on the line 2-2 of Figure 1, showing the novel valve in bottom plan; Yand Figure 3 is a partial view of the valve vof Figure 1 but on a larger scale.

The engine selected for illustration is of the two-cycle type and embodies an engine piston in a cylindery 12, which may have the usual water jacket 14 and which is closed -at its upper end by a detachable cylinder head 16. The charges of air for the engine cylinder are compressed in the crankcase and the products of combustion at the end of the power stroke of the piston are exhausted through a suitable conduit 18, the intake and exhaust being controlled by ports in the cylinder wall which do not show in the particular section of Figure 1 but whichare well known in engines of this type. The engine may if desired be provided with a suitable compression-relief valve to aid in starting.

The wall of the engine cylinder` and the cylinder head 16. are formed' with alined openings fora sleeve22 forming a. pump cylinder in which is reciprocated by a suitable cam or eccentric a pump plunger 24. The plunger 24 at the lower'end of its stroke passes below al passage 2'6 leading through the sleeve 22 into the engine cylinder. Preferably this takes place just before the exhaust port in the engine is uncovered so gases at a high temperature and under high pressure eov rush into the space above the pump plunger I therein is injected by its own pressure into the engine cylinder just before the piston lO reaches the top of its compression stroke.

A novel plug 30, secured by bolts or the like 32 to the cylinder head 16, projects into the opening in the cylinder head and seats against the end of sleeve 22. The plug 30 is formed with 'a conical valve seat for a conical disk valve 34 having a stem 3G journalled in an opening inthe plug 30 and operated by an arm 38 at its upper end. The valve 34 is held against its seat by a spring 40 confined between the top of the plug 30 and said arm 38, and the arm 3S is oscillated to operate the valve by a. forked lever 42 operated by suitable engine-driven cam or eccentric mechanism. Y

As best shown in Figure 3, the valve 34 is formed with an opening 44 at one side of its axis and which in one angular position of the valve registers With an opening 46 in the plug 30 to which the fuel is fed in any desired manner. Preferably relatively heafy fuel such as kerosene or distillate is use In operation. as plunger 24 is on its down stroke, lever 42 is operated to bring openings or passages 44'and 46 momentarily into regis- Lasarte projecting into the opening in the cylinder head and seated against the head ot said sleeve and formed with a valve seat, a disk-like valve in said seat, the valve and valve seat being formed with openings which register when the valve is in one angular position and try, to allow a small charge of fuel to be sucked into the pump cylinder, and immediately thereafter lever 42 again oscillates valve 34 to bring they passagesl 44 and 46 out of registry. `When the plunger 24 reaches the bottom of its stroke, the space in the cylinder above it is filled with exhaust gases at high temperature and pressure in which the smalldrop of fuelwhich has just entered is immediately vaporized. As the'engineylinder 10 comes upon its compression stroke the pump plunger 24 also rises to compress the mixture of exhaust gas and vaporized t'uel until just before the piston 10 reaches the top of its stroke the passages 28 and 26 register with each other and the fuel charge is injected into the engine Vcylinder Where it is immediately ignited by the high tems perature of the compressed air therein. It should be noted that. the pressure in the pump cylinder, instead of interfering with the operation of the fuel valve, is in a direction to hold the valve against its seat.

While one illustrative embodiment of the invention has been described in detail, it is not my intention to limit its scope to that particular embodiment or otherwise than b the terms of the appended claim.

I claim: An engine of the injection type having, in combination, an engine cylinder and a c vlinder head formed with co-aXial openings at one side ot the cylinder space, a sleeve in said openings forming a pump cylinder adjacent the engine cylinder, a pump plunger reciprocated in the sleeve to compress and inject successive charges of fuel, a valve head ilo lll()

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