US2015887A

US2015887A - Fuel injection means for compressorless internal combustion engines

Info

Publication number: US2015887A
Application number: US907A
Authority: US
Inventors: Eek Thorleif
Original assignee: Kockums Mekaniska Verkstads AB
Current assignee: Kockums Mekaniska Verkstads AB
Priority date: 1934-11-13
Filing date: 1935-01-08
Publication date: 1935-10-01
Anticipated expiration: 1952-10-01

Description

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FUEL I'NJECTION MEA S FOR COMPRESSORLESS INTERNAL COMBUSTIONENGINES I Filed Jan. 8,1935

a means according to the invention.

In the embodiment of invention shown,,the high uurnznjsmr Patented Oct. 1, u

- FUEL INJECTION it *SORLESSQ, INTERNAL COMBUSTION En GINES Th orleif Eek, Oslo, No'rway, assignor to Koch urns Mekaniska Verkstads Sweden, a corporation of Sweden" Aktiebolag, j Mal no, 1

ApplicationJanuary s, 1935, Serial No. 907

p In Sweden November 13, 1934 r i 3 Claims. (Cl. 299-1072) V The present invention refers to fuel injection means for internal combustion engines having no fuel compressor. More specifically the invention refers to such compressorless internal combustion engines in which the high fuel pressure required for the injection is brought about by means of a piston pump driven by a compressed fluid, jand whereinthe injection is performed by means of a nozzle controlled by aneedle valve,

In injection means of this kind, the invention hasfor its primary object toimprove the working conditions of the high pressure fuel pump so as to obtainan efficient fuel injections,

Generally speaking, the main characteristic of the invention is that the fuel conveying conduit between the high pressure pump and theneedle valve, or nozzle, is providedwith a shut-off valve means adapted to coact with thefmovable members of the high pressure piston pump in, sucha manner that the said conveying conduit is closed at the conclusion of the injection stroke of r the D p s i j i The result hereof will be that the fuel confined betweenthe fuel piston of the high pressure that the piston will be permitted to continue its injection stroke until the compression of the conflnedfuel is sufiicient for eifecting aicomplete stopping of the same, and in that the piston, after having been reversed at the, end of the injection stroke, may perform a certain part of its suction 1 stroke before the valve. member is opened again,

so that the pressure of the confined quantity of fuel has got time to decrease sufiiciently for eliminating the risk of after-injection of fuel into the engine cylinder.

An embodiment of the invention illustrated in the accompanying diagrammatical drawing which shows a longitudinal section of the upper portion of an engine cylinder equipped with the injection pressure piston pump is supposed to be provided with a differential piston .l thelarger piston member ofwhich is adapted to be driven by a comdecrease in 'a'sufiicient degree for eliminating an after-injection.

pressed fluid, whereas the smaller plunger member of the'same is adapted to exert the required pressure on the fuel, such differential piston being reciprocably mounted within a housing 3 enclos-. ing also theneedle valve 2. r i

The highly compressed fuel is injected through the engine after having at first passed a communication conduit 1 connecting the needle valve and'the nozzle with the fuel compression cylinder 8 of, the high pressure pump.

The shut-off valve member 6 is connected with the free end of the high pressure plunger by means of a coil spring 9, and said valve member is adapted to coact with a seat In provided at the 1 bottom end of the cylinder 8 and forming the inlet opening to the communication conduit 1. Y

i The fuel enters the cylinder Bbymeans of an admission channel I I, and the driving fluid for l3 by means of the pipe l2. When the differential piston l is moved downwardly under influence from the pressure within the cylinder l3, the fuel is compressed within the cylinder 8 and injected into the engine cylinder by the intermediary of the. communication conduit l, theneedle valve 2 and the nozzle 4. At the conclusion of the injection stroke of the pump, the valve member 6 approaches the seat In and is pressed, against the .same undercompression of 39 i r the spring 9, so thatthe inlet end of the conduit I becomes closed. The fuel confined between the lower end face of the fuel piston and the valve member 6 is thereafter compressed and arrests PATENT ornatthe nozzle 4 into the, combustion chamber 5 of the high pressure pump is admitted to the cylinder 20 the movement of the piston. The valve member 5 will be kept againstits seatalso during the first part of the suctionstroke of the piston, and until the pressure within thecylinder 8 has got time to' WhatI claim and desire to secure by Letters Patent is:- i V 1. In a fuel injection means for internal combustion engines of the character described, a high pressure piston pump driven by a compressed 5 fluid and adapted to raise thepressure-on the fuel in a. sufficient degree for injection into the working cylinder of the engine, an injection nozzle means mounted in connection with the engine cylinder and adapted for injection of the fuel therein, e valve means adapted for closing of said nozzle means, a communication conduit between said nozzle means and the high pressure fuel chamber of the piston pump, and a shut-offvalve means resiliently connected with the piston of the high pressure fuel pump and adapted for closing of the aforesaid communication conduit at the conclusion of the injection stroke of said pump.

2. In a fuel injection means for internal combustion engines of the character described, a high pressure fuel piston pump having a difierential piston the larger piston member of which is adapted to be driven by a compressed fluid, whereas the smaller piston member of the same is adapted to exert the required pressure on the fuel, an injection nozzle means mounted in connection with the engine cylinder and adapted for injection of the fuel therein, a valve means adapted for closing of said nozzle means, a communication conduit between said nozzle means and the high pressure fuel chamber of the piston pump, and a shut-off valve means resiliently connected with the smaller piston member of the differential piston and adapted for closing of the said communication conduit at the conclusion of the injection stroke of the pump.

3. In a fuel injection means according to claim 2, the additional feature, that the shut-01f valve means for the communication conduit is mounted at the free end of the smaller piston member of 10 the differential piston and adapted to coact with a seat at the bottom of the cylinder within which said piston member moves, such seat forming the inlet end of said communication conduit.

THORLEIF EEK.