US2818840A - Cylinder head construction - Google Patents

Description

Jan. 7, 1958 F. MCGQWEN CYLINDER HEAD CONSTRUCTION Filed Aug. 3, 195 s 2 Sheets-Sheet l NIT 8' 3 I? 2O H62.

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ATTOR 0 s R m w m w V O N w 1 M 8B (7 3 G F Jam-7,1958 F, MQGOWEN 2,818,840 CYLINDER HEAD CONSTRUCTION I Filed Aug. 3, 1955 2 Sheets-Shet 2 INVENTOR. FRAN K MCGOWEN CYLINDER HEAD CONSTRUCTION Frank McGowen, Muskegon, Mich., assignor to Continental Motors Corporation, Muskegon, Mich., a corporation of Virginia Application August 3, 1955, Serial No. 526,267

7 Claims. (Cl. 123-32) My invention relates to an internal combustion engine of the compression ignition type and more particularly to a cylinder head assembly for same.

Heretofore in the manufacture of engines of the compression ignition type, the fuel injection nozzles including their various operating parts, pump pressure inlets, and leak-off means have been made as assemblies separate from the cylinder head. This resulted in a rather complicated arrangement and installation, comprising separate leak-off conduits and fittings for returning fuel leakage from the nozzles to the fuel pump sump or suction portion and externally mounted nozzles, all subject to damage in handling and necessitating an additional accessory installation step after the basic engine assembly had been accomplished.

An inspection of any engine heretofore in use reveals a multitude of fuel pressure pipes and fittings, drain lines.

and fittings, and expensive externally mounted injection nozzles with a plurality of hold down bolts, and all of this equipment from time to time becomes damaged, necessitating costly replacement subject to maintaining of all these parts in stock.

In addition, the parts of the nozzle assembly were to a certain extent insulated from the cooling system of the engine by virtue of the housing in which they were enclosed. This results in a definite limitation on the service life of the nozzle and associated equipment.

Therefore, an object of my invention is to facilitate the cooling of the fuel injection nozzles and other parts by eliminating the separate housing incorporating its function into the basic assembly in closer communication with the engine cooling system and in providing supplementary cooling means by circulating normal fuel pump overflow through a passage in the cylinder head and around the nozzle parts.

Another object of my invention is to eliminate the complex installation of pipes and equipment associated with fuel injection nozzles by connecting a passage through the cylinder head with drainage of injector leak-off fuel from each nozzle to the fuel pump overflow, and by providing each nozzle with a plug portion installed directly on the cylinder head and serving the multifold purpose of sealing the nozzle section, housing some of the parts, and retaining the whole installation in the cylinder head.

For a more detailed understanding of my invention, reference may be had to the accompanying drawing illustrating a preferred embodiment of my invention in which like characters refer to like parts throughout the several views and in which:

Fig. l is a vertical elevation view of an engine with the fuel injection system installed,

Fig. 2 is a section on line 22'of Fig. l, and

Fig. 3 is a section on line 33 of Fig. 2, and

Fig. 4 is a cross-section perspective view taken substantially on the line 4-4 of Fig. 1.

Referring first to Fig. 1 of the drawing, an internal combustion engine of the compression ignition type is shown having a cylinder head 11 suitably secured to the nited States Patent ice cylinder block 12 by bolts 13 or the like. A fuel injection pump 14 of conventional design is suitably installed or mounted on the engine and has a fuel pressure distribution head 15 and suction intake means 16. A plurality of fuel pressure pipes 17 are installed or otherwise secured at the pressure distribution head 15 of the pump by fittings 18 or the like, said pipes 17 conventionally mounted on the cylinder head by mounting blocks 19 or any other means, and leading to fuel pressure inlet fittings 20, the quantity depending on the number of fuel injectors installed.

A fuel overflow conduit 25 is installed between the pump 14 and the cylinder head 11, and serves to direct normal overflow fuel from the pump into a longitudinal passage 55 within the cylinder head 11. A fuel drain line 26 similarly connects the other end of the longitudinal passage 55 with the suction intake means 16 of the pump 14. Fuel intake to the pump 14 is through intake pipe 27.

The conventional fuel pump 14 is shown in Fig. 4, in which the suction intake means 16 may comprise a gear type pump 16a having an intake port 16b connected with the fuel drain line 26 and the intake pipe 27, and an outlet port 160 connected through a passage 16d to the pressure distribution head 15. The pressure distribution head 15 preferably comprises a plunger 15a vertically reciprocated and rotated by any suitable drive from the engine. In operation, the plunger 15a moves downward and fuel from the passage 16d enters a chamber 15b. The plunger 15a moves upward, forcing the fuel from chamber 15b under high pressure through a delivery valve 150 into a passage 15d and to an annular groove 150 in the plunger 15a from which it is distributed to the fuel pressure pipes 17. As the plunger 15a reciprocates, a port 15f will come into alignment with overflow passages 15g, and overflow fuel from the chamber 15b will pass down through a central plunger passage 15h thereto and flow to the fuel overflow conduit 25.

Fig. 2 showing a section through the cylinder head 11 illustrates an inner wall 11a of the cooling system, a high pressure fuel passage 29, a combustion chamber 30 and a step drilled and reamed bore 31 open to the combustion chamber 30 and containing a fuel injector nozzle assembly 28.

The fuel injector nozzle assembly 28 comprises a conventional fuel injector nozzle tip 32, a spool 33 having a passage 34 in open connection with the nozzle tip 32 and with the high pressure fuel passage 29 in the cylinder head 11 for directing inlet pressure fuel to the nozzle tip, the spool also having a step drilled and reamed bore 35 through its center. A fuel injector pintle is constructed to fit within the bore 35 of the spool 33, and is threaded at its outer end for the installation of two adjusting nuts 41 or suitable adjusting means. The preferred structure of the injector nozzle embodied in my invention also comprises an expanding washer 42 and a backup washer 4.3 installed outwardly of the spool 33, however the backup washer 43 may be eliminated. A hold down plug 45 or cap is suitably screwed or otherwise secured into the cylinder head bore 31. This plug has a recess 46 which contains a pressure spring 47. A standard O-ring 48 or other sealing device prevents leakage from escaping past the plug 45. Also, each plug forms with the cylinder head bore or recess 31 an annular passage 49. One or more ports 45a connect the annular passage 49 with the interior of the plug 45.

When installed, the inner end 50 of the plug 45 bears against the back up washer 43 or the expanding washer 42, serving to secure the spool 33 inward against the nozzle tip 32. The spring 47 serves to retain the pintle 40 and provide pressure to insure proper operation. A washer 51 is installed at the inner end of the second step of bore 35 and serves to seal the major portion of the bore 35 from the compression chamber pressure.

All of the above parts comprise the essential structure of the fuel injector nozzle assembly 28 operating in the conventional manner. The distinction between applicants assembly and formerly employed types is that the cylinder head 11 and nozzle assembly are completely assembled before assembly of the head to the cylinder block. The cylinder head 11, moreover, is longitudinally bored as at 55, said bore or passage intersecting and in open communication with annular passages 49 and ports 45a.

When the fuel pump 14 is operating, the excess or overflow fuel, instead of being directly connected to the sump or suction side of the pump as heretofore, is directed through conduit 25 to one end of the longitudinal passage or bore 55. This fuel subsequently circulates within all the recesses 46 of the plugs 45, and around the parts of the fuel injector nozzle described above, thus serving as an eflicient cooling means for these parts. In addition, any leak-off fuel which passes from the injector nozzle tip 32 into the central sleeve bore 35 and past the pintle 40, is subsequently carried through passage 55 with the overflow fuel. This fuel then passes out the other end of the longitudinal passage 55 into the drain line 26 and thence to the suction intake means 16 of pump 14.

An additional cooling characteristic of this improved fuel injector nozzle installation is the proximity of the injector parts and the bore 33 to the wall 11a of the engine cooling system.

While I have illustrated but one embodiment of my invention, it will be apparent, however, to those skilled in the art to which my invention pertains that various changes and modifications may be made therein without departing from the spirit of my invention or from the scope of the appended claims.

I claim:

1. In a multi cylinder internal combustion engine of the compression ignition type having a cylinder head, a fuel induction system for said engine including a fuel injection pump having fuel discharge means and a fuel overflow means, and a plurality of fuel discharge lines leading respectively from said fuel discharge means to the engine cylinders, a plurality of fuel injection nozzle assemblies, said fuel discharge lines carrying'fuel under pressure to said fuel nozzle assemblies, said cylinder head having a plurality of transverse bored openings and in each of which a nozzle assembly is fitted, a hollow plug secured in the outside portion of each bored opening to back up the nozzle assembly and to seal against leakage of fuel therefrom, said cylinder head having a longitudinal bore intersecting each of said bored openings, each of said plugs having openings placing the interior of said longitudinal plugs into open communication with said longitudinal bore, means connecting the fuel pump overflow means with one end of said longitudinal bore to flow said overflow fuel therethrough and in heat exchange relation with respect to each of said fuel nozzle assemblies, and means connecting the other end of said longitudinal bore with the fuel supply system on the suction side of said pump.

2.'In a multi-cylinder internal combustion engine of compression ignition type having a cylinder, a fuel induction system for said engine including a fuel supply and a fuel injector means including a fuel pump having fuel discharge means and a fuel oveflow means, a plurality of fuel feed lines leading respectively from said fuel discharge means to the engine cylinders, a plurality of fuel injection nozzle assemblies respectively associated with the engine cylinders and each connected with one of the fuel lines aforesaid, said cylinder head having a plurality of recesses for housing said nozzle assemblies and a longitudinal passage intersecting said recesses and havinginlet and outlet ports, and means connecting said longitudinal passage with said fuel injector means and connecting the inlet port thereof with the fuel pump overflow means to circulate said overflow fuel through the passage and recesses, the outlet port means connected with the fuel supply on the suction side of the pump, the circulation of said overflow fuel aforesaid serving to cool the fuel nozzle assemblies and to drain fuel leakage from said recesses.

3. In a multi cylinder internal combustion engine of the compression ignition type having a cylinder, a fuel induction system for said engine including a fuel supply and a fuel injector means including a fuel pump having fuel discharge means and a fuel overflow means, a plurality of fuel feed lines leading respectively from said fuel discharge means to the engine cylinders, a plurality of fuel injection nozzle assemblies respectively associated with the engine cylinders and each connected with one of the fuel lines aforesaid, said cylinder head having a plurality of recesses for housing said nozzle assemblies and a longitudinal passage intersecting said recesses and having inlet and outlet ports, and means connecting said longitudinal passage with said fuel injector means and connecting the inlet port thereof with the fuel pump overflow means to circulate said overflow fuel through the passage and recesses, the outlet port means connected with the fuel supply on the suction side of the pump, the circulation of said overflow fuel aforesaid serving to cool the fuel nozzle assemblies and to drain fuel leakage from said recesses, said fuel nozzle assemblies each comprising a spring loaded pressure actuated nozzle valve and extended into said head recess, a plug for closing each recess and provided with an interior recess for housing the extended portion of the fuel nozzle assembly, and provided with openings placing the interior of the plug in open communication with said passage.

4. In a multi cylinder internal combustion engine of the compression ignition type having a cylinder, a'fuel induction system for said engine including a fuel supply and a fuel injector means including a fuel pump having fuel discharge means and a fuel overflow means, a'plurality of fuel feed lines leading respectively from said fuel discharge means to the engine cylinders, a plurality of fuel injection nozzle assemblies respectively associated with the engine cylinders and each connected with one of the fuel lines aforesaid, said cylinder head having a plurality of recesses for housing said nozzle assemblies and a longitudinal passage intersecting said recesses and having inlet and outlet ports, and means connecting said longitudinal passage with said fuel injector means and connecting the inlet port thereof with the fuel pump overflow means to circulate said overflow fuel through the passage and recesses, the outlet port means connected with the fuel supply on the suction side of the pump, the circulation of said overflow fuel aforesaid serving to cool the fuel nozzle assemblies and to drain fuel leakage from said recesses, said fuel nozzle assemblies each comprising a spring loaded'pressure actuated nozzle valve and extended into said head recess, a hollow plug for closing each recess and having an annular seal to seal off leakage from the cylinder head recess to theoutside and provided-with an annular passage communicating with'the cylinder-head passage, each of said plugs having ports placing said annular groove in open communication with the interior of the hollow plug.

5. In a multi-cylinder internal combustion engine of the compression ignition typehaving a cylinder, a 'fuel induction system for said engine, including a fuel supply and a fuel injector means including a fuel pump having fuel discharge means and a fuel overflow'means, a plural ty of fuel feed lines leading respectively froms'aidfuel d1s-' charge means to the ngi cylinders; 11 P injection nozzle assemblies respectively associated with the engine cylinders and each connected with one of the fuel lines aforesaid, said cylinder head having a plurality of recesses for housing said nozzle assemblies, said cylinder head provided with passage means connecting each of said cylinder head recesses, and connecting ducts connecting the cylinder head passage at one end to the fuel overflow means of said pump and the other end to the fuel supply on the suction side of the fuel pump.

6. In a multi-cylinder internal combustion engine of the compression ignition type having a cylinder, a fuel induction system for said engine including a fuel supply and a fuel injector means including a fuel pump having fuel discharge means and a fuel overflow means, a plurality of fuel feed lines leading respectively from said fuel discharge means, to the engine cylinders, a plurality of fuel injection nozzle assemblies respectively associated with the engine cylinders and each connected with one of the fuel lines aforesaid, said cylinder head having a plurality of recesses for housing said nozzle assemblies, said cylinder head provided with passage means connecting each of said cylinder head recesses, and connecting ducts connecting the cylinder head passage at one end to the fuel overflow means of said pump and the other end to the fuel supply on the suction side of the fuel pump, said passage extending longitudinally of the cylinder head substantially normal to the axes of said recesses and com prising a longitudinally drilled passage intersecting each of said recesses.

7. In a multi-cylinder internal combustion engine of the compression ignition type having a cylinder, a fuel induction system for said engine including a fuel supply and a fuel injector means including a fuel pump having fuel discharge means and a fuel overflow means, a plurality of fuel feed lines leading respectively from said discharge means to the engine cylinders, a plurality of fuel injection nozzle assemblies respectively associated with the engine cylinders and each connected with one of the fuel lines aforesaid, said cylinder head having a plurality of recesses for housing said nozzle assemblies, said cylinder head provided with passage means connecting each of said cylinder head recesses, and connecting ducts connecting the cylinder head passage at one end to the fuel overflow means of .said pump and the other end to the fuel supply on the suction side of the fuel pump, said passage extending longitudinally of the cylinder head substantially normal to the axes of said recesses and comprising a longitudinally drilled passage intersecting each of said recesses, means plugging the recesses, and means providing for flowing the fuel circulated in said passage through said recesses in heat exchange relation with each of said fuel nozzle assemblies.

References Cited in the file of this patent UNITED STATES PATENTS 2,326,171 Reggio Aug. 10, 1943 FOREIGN PATENTS 1,006,542 France Jan. 23, 1952

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