US1871444A - Fuel injection means for internal combustion engines - Google Patents

Description

Aug. :1, 11932.. G. w. CODRINGTON FUEL INJECTION MEANS FOR INTERNAL COMBUSTION ENGINES Filed Sept 15, 1950 INVENTOR ATTORNEYS Patented Aug. 16, 1932 UNITED-STATES PATENT OFFICE GEORGE W. CODBINGTON, 01 LAKEWOOD, OHIO i FUEL INJECTION MEANS FOR INTERNAL COMBUSTION ENGINES" Application filed September 15, 1980. Serial 1T0. 481,870.

This invention relates to liquid fuel injection means for internal combustion engines, and particularly has to do with that type of such injection system wherein each engine cylinder is served by a separate injection pump, which receives liquid fuel at a' low supply pressure and provides an outlet pressure suiiiciently high to deliver fuel into the combustion chamber-against the compression pressure of the latter.

More particularly the invention has to do with the valves of the injection pump, and briefly the invention comprises an arrangement of pump inlet and outlet valves, one within the other, and a flexible pump outlet connection leading frgm the outer valve to the injection nozzle in the cylinder wall. The inlet valve is preferably selected to be the outer one, so that gear may be associated therewith to open the same to control the pump output so as to effect injection cutofi.

The general object of the invention is to provide a structure of the described nature which shall be-inexpensive yet sure in ope1 ation.

The exact nature of the invention together wlth further objects and advantages thereof.

will be apparent from the following description taken in connection with the accompanying drawing in which Fig. 1 is an elevation generally in section and largely conventionalized, showing an embodiment of my invention together with the principal pertinent associated parts; and Fig. 2 is an enlarged detail of parts'appearing in Fig. 1.

With reference now to the drawing, 1 indicates a portion of the combustion chamber wall of the engine cylinder to be served. To this end, a nozzle 2 is inserted in the wall in the usual manner, and provided'with outletopenings 3. An

zle 2 to control the openings 3, with an associated spring 5 tending to maintain the injection valve seated, and a piston head 6 by which the injection valve may be unseated provided having a plunger 8 movable in a pressure in the chamber 7 injection valve 4 may bearranged as indicated to seat within'the nozvalve.

' cylinder 9 which may have a liner 10, to pro-- vide an expansible chamber 11. The cylinder 9 may conveniently have the form indicated so that it may bebolted as at 12 to a housing 13 in turn secured with the crank case hous- 65 7 ing 14 of the engine. The plunger 8 may thus be located in alignment with the cam shaft 15 of the engine, so that the plunger may be actuated by a cam 16 suitably located on the cam shaft. To this end the plunger is provided with a head 17 and the usual tappet 18 and associated cam follower 19 are arranged between the cam 16 and the plunger head. A compression spring 20 takes up lost motion of the parts toward the cam 16 and thus ses the plunger 8 to reciprocate in timed relation with the other engine parts when theengine is running.

- Thepump cylinder 9 is open opposite the end of is set a valve block 21 secured by a cap 22 turned into the end of the cylinder as indicated. The valve block 21 has a through opening 23 aligned with an opening 24 in the end of the cap 22. The pump inlet valve 25 is provided with a valve head 26 seating upon the valve block 21 and a crosshead portion'27 which may be a separate part cured by threading as indicated, bearing in, the opening 24; with a shank portion extending between the valve head and crosshead portions. The inlet valve is maintained seated upon the block 21' by a compression spring 28 within the cap 22 hearing between the valve block and a flange 29 of the valve crosshead portion. The bore 23 in the valve block 21 is enlarged back of the valve seat to form an annular chamber 30 which has communication with a low pressure source of fuel supply asby the lead 31 in the pump cylinder and valve block, and piping 32. The' inlet valve 25 is itself hollow with the central through opening 33- shown. At the head end 26 of the valve this opening b 33 is tapered inwardly to provide a seat 34 5 for an outlet or discharge valve 35. 'The outlet valve is of smaller diameter than the bore 33 so that an annular passage is had thereabout and therealong, through the inlet Alignment of the valve 35 may be the plunger 8 and in the open end 7 l.

caused by the cam 16 to move inwardly of.

cured one end of a connection pipe 42 which leads to the injection nozzle 2 of the engine cylinder and thereat has connection as at 43. The pipe 42 has suificient strength to withstand the injection output pressures of the pump, and is sufficiently flexible to allow a slight movement of the pump inlet valve.

Operation will be as follows: When the cam 15 allows the plunger 8 to move outwardly of the chamber 11 under the action of the spring 20, the outlet valve 35' remaining seated under the action of its spring 37, the inlet valve will be lifted from its seat inwardly of the chamber 11, and liquid fuel will be supplied to the chamber 11 through the pipe 32 up to the displacement of the plunger 8. When the plunger 8 is the chamber 11. the inlet. valve 25 will seat against the valve block 21 and the outlet valve 35 will be lifted from its seat 34. Fuel at injection pressure will then be forced by the plunger, from the chamber 11 toward the chamber 7 of the injection valve, by way of the opening in the inlet valve and about the outlet valve, through the opening in the plug 38. and through the connection pipe 42. The injection pressure will unseat the injection valve 4 and the injection will be had through the nozzle opening 3 into the combustion chamber.

Injection would continue through the inward stroke of the plunger 8, and the successive injection charges would all be equal and amount to the displacement of the plunger in the chamber 11 were only the described parts provided.

However, as will be appreciated by one familiar with the art, it is desirable that the amounts of the charges be variable that the engine output may be controlled, and it is also desirable that the injection periods all commence at the same time in the engine cycle and be varied as to cutoff to this end.

So a rocker 44 actuated by push rod 45 may be arranged with its end 46in the form of a yoke bearing against the end of the 'crosshead 27. Thus the pump inlet valve 25 may be unseated by the rocker. 44 against the action of the spring 28 at any time in the pump cycle; and the push rod 45 may be arranged in any convenient and usual manner to be actuated periodically in the engine cycle, and under governor control at difierent points in .the successive working strokes of the injection pump, to effect injection cutofi.

What I claim is:

Liquid fuel injection means for an internal combustion englne comprisinginjection pump means having a valve-supporting 'body, a hollow inlet valve seating in sald body and having a tubular stem part extending through the wall thereof, an outlet valve seating within said inlet valve, said inlet valve having a flexible pump outlet connection without said body and providing communication with the inlet valve. hollow, and unseating gear without said body and associated with said inlet valve stem to control the pump output.

In testimony whereof I hereby aflix my.

signature.

GEORGE 37V. CODRINGTON.

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