US2222274A - Fuel system for internal combustion engines - Google Patents

Description

Nov. 19, 1940. A. K. ANTONsx-:N

FUEL SYSTEM FRv INTERNAL COMBUSTION ENGINES Filed Nov. '19, 193s ff .f

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ANKER K.ANTONSEN.

ATTORNEYS Patented Nov. 19, 1940 STATES PATENT orFlce ENGIN Anker K. Antonsen, Waterloo, Iowa, assigner to vJohn Deere Tractor Company. Waterloo, Iowa,

a corporation of Iowa Application November 19, 1933 Serial No. 2411,35?,

4 Claims.

The present invention relates generally to 1nternal combustion engines and more particularly to fuel systems for engines of the compressionignition type.

Heretofore a certain amount of difficulty has been experienced `inl priming the fuel system and ridding the filter and injection pump of air when initially filling the system or after running the system dry, and it has been the practice in the past to manually vent both the filter and injec tion pump to overcome this objection.

The principal object of the present invention is to provide a self-priming fuel system which will vent itself of all entrapped air as soon as fuel is poured into the tank and the engineI is rotated for starting.

another object of the present invention is to provide a removable cylinder head of novel design embodyingl a fuel injectionpump mounted bodily on the head and removable therewith so that only thelovv pressure fuel line need be dis connected when'the cylinder head is taken off..

Still another object is to provide a protective filter between the injection pump and the point P at which the fuel line isdisconnected to prevent any dirt which might enter the fuel line during dismantling operations from clogging or othervvise damaging the pump or injection nozzles.

These and other objects and advantages of the present invention will become apparent after a consideration of the following detailed description of a preferred embodiment thereof, reference being had to the appended drawing, in which Figure i is an elevational-view, partially sectioned, of the fuel system and cylinder head of a two cylinder Diesel engine of the horizontal type, embodying the principles of my invention; and l Figure 2 is a fragmentary side view, drawn to reduced scale, of the cylinder head shown in Figure l.

Referring now to the drawing, the reference numeral it indicates the cylinder block of a hori` zontal Diesel type engine having two cylinders arranged side by side, and fixedly secured to the l end thereof, as by bolts Ii, is a cylinder head i2.

The cylinder head It is provided with a cam shaft compartment I3 Within which is disposed a transversely arranged cam shaft I4 journaled in suitable bearings l5 and driven through a bevel pinion It and gear by a shaft 2l. The

shaft il is driven, in turn, from the engine crankshaft (not shown) with which it is operatively connected by any suitable driving means. A pair of cams 22 on the cam shaft I4 engage rollers (Cl. 12d- 139) 23 journaled in the bifurcated ends of push rods 24 -to actuate the pistons of a fuel injection pump 25 which is xedly mounted on the cylinder head l2. The fuel pump 25 is mounted in an inverted position, receiving the fuel through an intake pipe 26 which enters the side of the pump through a connection 2l and pumping the fuel under pressure through fuel lines 3U and di which are connected by fittings 3u' and Eli to the bottom or um:v er side of the pump housing. The fuel lines 30 and 3i carry the fuel to injection nozzles or valves 32 and i3 which open into the combustion chambers (not shown) of their re-n spectlve cylinders and the fuel is injected in a finely atomized state into each of the said com bustion chambers near the peak of their compression cycles. As is vvell understood in the art, the finely divided fuel is ignited by the heat of compression and expands to drive the engine. ri'luespeed and power output of the engine are regulated in a conventional manner by means of a by-pass control rod it projecting laterally from the pump it and which operates to meter the fuel for each injection, the control rod ti being con nected by linlrage :it to any suitable governor Op control lever (not shown). ln the embodiment illustrated, the injection pump, fuel lines, nozzles, and control linlrage are enclosed and protected against dust and dirt by a cover plate it which is secured to the cylinder head by bolts lil.

Fuel for operating the engine is carried in a fuel tant. 4t and passes first through a primary fuel filter di and then a secondary or protective filter 42 before reaching the pump it. The purpose of the primary filter di is to remove the particles of dirt or other foreign matter from the fuel and thus prevent clogging or fouling of the minute passagevvays and apertures in the pump 2t and injection nozzles iii, The secondary filter it acts to catch any dirt that might get through the first filter, although its principal 'function is to prevent the entrance of dirt into the intake pipe it Whenever the cylinder head i2 is removed for thepurpose of an overhaul, as will become apparent presently.

The primary; fuel lter ti consists of a body or housing 43 which is divided by a Wall 4t into two vertically spaced chambers, the upper one comprising an intake chamber t5 and the lower one an outlet chamber t6. A domed cylindrical case 5t is fixed to and extends laterally from one side of the housing 4t, enclosing a filter chamber 41, and disposed within the chamber M is a lter element or cartridge tl of conventional design. A passage 52. connects the intalre chamber 45 with the iilter chamber and an orifice connects the filter cartridge i serially with the outlet chamber l. A fuel pipe line fit is connected through a suitable valve and sediment bowl fitu ting 55 to the lowest portion of the fuel tank and is joined by a connection il@ with the intake chamber @35. A vent pipe Sii is connected at to the highest point in the intake chamber and also at 6?. to the highest point on the fuel tank lo dil, providing a continuous upward path for air to flow from the filter 1li to the air space in the tank fill, thus by-passing the line lli and the fitting which is not selfprimnig- The filter (il, as shown, is actually a commern lo cial filter of the type originally intended to operate in a vertical position, but have placed. it in a horizontal. position to make it self-priming, as will be explained presently. The fuel inlet connection is made at the opening which was go originally used for the vent valve. The opening that was originally intended for fuel inlet, have used for the continuous vent connection Si. Thus, a continuous upward path. for air is provided through the filter 5.1i.

A fuel pipe line 53 is connected at @t to the lowest point in the outlet chamber offthe primary fuel nlter (il and is joined by a disconnectable fitting 55 to the secondary filter ll. The latter comprises a cylindrical housing xedly secured in any suitable manner to the cylinder head l2 and havinga filter element Gl contained therewithin, the intake pipe 26 being connected to the outlet of the filter 232.

For the proper operation of my invention, it is necessary that the primary filter di be placed at an elevation higher than the secondary nlter 42, and that the fuel tank dll be higher than the primary filter M so that the fuel lines 2S, 83 and 54 all slope upwardly or extend vertically from the injection pump 25 to the fuel tank 49. When the fuel tank 40 is lled after assembly or after running the system dry, the fuel flows by gravity down through the line 54 to the filter di; filling the intake chamber and casing 5t, 45 then passing through the filter cartridge 5I and 'filling the ou-tlet chamber 45t. The air in the lines and lter meanwhile escapes through the vent line 60 back to the fuel tank lill. As the oil continues to flow by gravity down through the fuel line 63, lter 32, intake pipe 25, and into the injection pump 2li, the air bubbles trapped in the system below the primary filter li work their way up through the lines and filters, escaping through the vent line Sil. By reason of the inverted position of the cylinders of the injection pump 25, the pistons being forced downwardly in the cylinders during compression and the fact that the outlet lines 'Jil and 3i are con nested to the compression chambers of the pump below the intake pipe 25, any entrapped air tends to escape back through theupwardly sloping line 26, lter 42 and pipe S3, while the fuel is retained. In the case of pumps mounted in a conventional manner with the pistons acting upwardly during compression and the fuel lines connected with the tops of the cylinders, it is necessary to vent the cylinders by loosening the high pressure fuel line connections. Moreover, in my arrangement, it will be evident to those skilled in the art, that the inverted pump forces the fuel through the outlet lines and by-passes air, while in the conventional arrangement, the air is forced into the fuel lines and fuel is bypassed. While l have shown and described the 'lppmp as being substantially vertical in its in- Ff'I/L vetted position, it is possible to obtain. the self- 4priming action at angles between. position and a substantially horizontal position.

To remove the cylinder head i?. from the cylinder block. the only fue?. line disconnection is at the low pressure where 'the pipe line connects into the secondary fil f the fuel pump together with the nig sure lines 3o, 3l, and injection valves 32, and the low pressure pipe and protec" "ve :lter G2, remain intact with the cylinder head and are removed bodily therewith. Thus, the injection pump and nozzles are protected against the enm trance of dirt which might cause clogg' any such dirt that might get i...:o the in of the filter d2 would be caught and retainecdiy the nlter element While I have shown and tion as applied to sol; ignition engine, do not be limited to this partie ar oise details shown and de tain of the may be applied to othe. bustion engines.

What .l claim as my l. In an engine of described rnv invenfention is:

e class described having a removable cylinder the combination of a fuel injection pump dlymounted on said cylinder head for removal. therewith, at least one injection nozzle mounted on said cylinder head, a high pressure fuel conduit connecting said pump and said nozzle, a protective fuel filter device associated with said cylinder head and removable therewith, said device being connected with the low pressure side of said pump, a fuel supply means, and a disconnectable fuel supply pipe connecting said supply means and said lter device. l

2. In an engine of the class described having a removable cylinder head, the combination of a fuel injection pump xedly mounted on said cylinder head for removal therewith, at least one injection nozzle mounted on said cylinder head, a high pressure fuel conduit connecting said pump and said nozzle, a protective filter carried on said cylinder head, an intake pipe connecting said protective filter with said pump, a primary fuel filter disposed at an elevation higher than said pump, a fuel tank disposed higher than said primary fuel filter, fuel pipe lines connecting said protective filter with said primary nlter and said primary filter with said fuel tank, and means for disconnecting said fuel pipe line between said protective filter and said primary fuel lter.

3. In' a compression-ignition engine, the combination of a cylinder head having injection nozzles, an injection pump nxedly mounted on said cylinder head in inverted position, fuel lines connecting said pump with said nozzles, an intake pipe connected with said pump above said fuel line connections, a protective nlter mounted on said cylinder head above the point of connection of said intake pipe with said pump, said intake pipe being connected with said protective nlter, a primary fuel filter disposed above said protective lter, a fuel tank disposed above said primary lter, fuel pipe lines connecting said protective filter with said primary filter and said lprimary filter with said fuel tank, an air vent pipe connecting said primarylter vwith said fuel tank, and means for disconnecting said fuel pipe line between said protective filter and said primary fuel filter. 1

I Modem iii fi. 1in en engine of time class deecriioed iioving o removable cylinder' heed, u fuel injection pump supported in xed reldtion on seid cylinder head in inverted position with its piston adapted to be forced downwardly during the pressure stroke, on injector nozzle mounted on seid cylinder head, o high pressure discharge conduit connected to said nozzle and to said pump at the lower portion thereof, e protective iiiter mounted on scid cylinder head, conduit Ineens connecting said lter with seid pump at a, point on the latter higher than the discharge conduit connection, a fuel reservoir, and a supply conduit detachabiy conn nected to said protective :tilter and sloping upwardly toward said reservoir.

ANKER K. ANTONSEN.

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