US1698356A

US1698356A - Fuel feed for diesel-type internal-combustion engines

Info

Publication number: US1698356A
Application number: US356774A
Authority: US
Inventors: Andre C Attendu
Original assignee: Individual
Current assignee: Individual
Priority date: 1920-02-06
Filing date: 1920-02-06
Publication date: 1929-01-08
Anticipated expiration: 1946-01-08

Description

Jan. 8, I929.

A. C. ATTENDU FUEL FEED FOR DIESEL TYPE INTERNAL COMBUSTION ENGINES Filed Feb 6. 1920 1 AW... Km I I T mw Patented an. :8, 1929.

1mm. c. n'r'rnnnu, or MONTREAL, QUEBEC, CANADA.

Font rn'nn r012. nmsnn'ryrn InrERimL-ooMBusrIoN ENGINES.

' Atacama February 6,1920. Serial 170.356,?74.

v This invention relates to improvements in process of and apparatus for supplymg fuel oil to Diesel type internal combustlon engines,

and the object of the invention is to provide.

5 for the feeding of oil from a pressure slightly below the air pressure or slightly below the cylinder pressure if the oil is injected d rectly.

' A further object is to provide an 011 feedin "and measuring device operating under on y a slight difference of pressuresbetween intake and discharge wherebyflexibility and freedom from leakage may be obtainedand small parts of .sim le construction employed. ,A still further-o ject is to provide a measuring device which is at every stroke preared to deliver the maximum amount of oil fraction of the oil available for delivery.

A further object is to provide a device which may be easily and inexpensively manufactured and which-will not readily get out of order. I

he device consists briefly of a small auxiliary' reservoir-on the engine. in which fuel oil ismaintained at a. constant pressure only slightly-below the pressureof the. intake a r oriof the cylinder pressure. One or more pumpsare provided in conjunction with the reservoir for feedin oil therefrom into one or more cylinders. 1 n the suction stroke, the pistons of these pumps move to the llm lt of their travel, so as to draw a full char e. On the force-or feedingstroke, the trave of the pistons may be stopped at any desired point to re ulate the amount of oil delivered. The 011 1s forced into the auxiliary reservoirby a suitable pump operating proportionatelyto the engine speed and arranged to dehver a greater volume of oil per unit of time than can be handled by the feed pumps, the surplus oil escaping from the reservoir through an ad-.

'justa'ble relief valve, so that the pressure in the reservoir is maintained uniform.

In the drawings which illustrate the invention Fig. 1 is a cross section on the" line 1- 1,

Figure 2, illustrating one form of device embodying the invention.

tion.

Referring more particularly to the draw.-

ut which may be regulated to deliver any Fig. 2'is avlew partly in longitudinal secings, 1 1 designates a reservoir capable of sustainlng very considerable'internal pressures and having heads 12, one not shown, and 13'designates a casing enclosing the operat ng'parts of the measuring device and having hand-hole plates 14 giving access thereto. A cam shaft or-driving shaft 15 passes through the casing. A pressure pump, designated as a whole by the numeral 16, is provided for supplying fuel oil to the reservoir '11.- This pump is preferably operated from the "shaft 15 and may forconvenience be en- 7 closed in the casing 13. It will be understood,

. however, that this pump maybe entirely separate and located at any suitable point.

' The pump 16 comprises a body 17 provided with flanges 18 for attaching it'tothe casing 13 and having any suitable number of bores 19'which are preferably equal in number to the feed pumps which it supplies and which area-11in communication with a supply passage 20 to which the suction pipe 21 connects.

The pump pistons 22 are preferably of the solid plunger type and operate on the feed ing strokes as valves to close oi the bores 19' from'the supply passage 20, so that the oil is driven out of the bores through the check valves .23 into the discharge pipe 24 and thence through the check valve 25 into the reservoir 11. The outer end of each piston is .1

preferably provided with a roller :26 running on a cam or eccentric 27 fixed to the shaft 15. A spring 28 is arranged between a suitable abutment:29 at the outer end of each piston and the pump body 17. It will thus be seen that the pistonsare positively operated by the cams on the discharge strokes and are operated by the springs on'the suction strokes.

The reservoir 11 is provided, with an ad justable relief valve 3 0 of any suitable design having an overflow p1pe 31 which leads back to a main oil reservoir or to the suction pipe One or more feedin and measuring pumps 32 are provided in t e reservoir and each comprises a barrel 33 formed integral with the reservoir or suitably connected thereto interior of the reservoir. The plunger 35 of each pump projects beyond the lower end of the-barrel and 1s provided with a pair of 00-1- having inlet ports 34. communicating with the

Y lars

36 and 37,between which the forked extremi ty of an o erating lever 38 embraces the plunger. The ever 38 is operated by a cam 39 on the shaft 15 'to press against the lower collar 37 and operate the plungerion its suction stroke and at the same time compress a spring 40 located between the collar 37 and an adjustable seat41 provided in the casing 13.

The opposite end of the pump is provided with an outwardly-opening check valve 42 and communicates with a fuel feed pipe 43 leading to an injector not shown or other means for deliverin oil into an engine cylf' cinder. It will thus eseen that feed pumps are positively operated on'th'e suction strokes from the shaft 15 and are operated on the feed strokes by the springs 40. f

In order to regulate the length of feed strokesand therefore the amount of oil delivered by each pump, a tapered member 45.

is interposed between the reservoir 11 and the collar- 36 of each pump. It is obvious that by shifting this regulator to interpose thicker :or thinner parts thereof between the collar 36 and the reservoir, the stroke oflthelphmger may be regulated;

The feed pumps may be of the fitted plunger type shown or obviously may be of the being immat erial except as regards simplic- Dating plunger type, the construction ityof manufacture. .7

Theoperation of the device is'as follows The force pump 16, which is operated by the shaft 15 in -suitable proportion to the speed of the engine, delivers fuel oil to the reservoir I 11 in excess of thecapacity of the feed pumps 32 to withdraw oil from the reservoir, so that there is alwaysa surplus of oil which escapes through therelief valve and is returned to the suction sideof, the pressure pump. In this way, a fixed pressure is maintained in the reservolr 11, which bears any desired relation to the airsupply pressure or to'the. cylinder pressure oftthe engine according as the valve 30 is adjusted. Preferably, the difference inpressures is not more than fifteen pounds so that the feed pumps 33 are operatin' under very easy conditions and are not su ject to leakage, especially in the check valves 42. As the shaft 15 revolves, the cams 39 oscillate the levers 38 to draw the plungers out of the barrels 33, that is, to operate the plungers during their suction strokes. During the suction strokes, the valves 42 are closed by backpressurgso that a vacuum is drawn in the arrels 33 until the plungers uncover the ports 34, whereupon oil from the reservoir;

rushes in and completely fills the ump barrels. During the suction strokes, t e springs have been compressed between the collars '37 and abutments41, and, when the cams 39 release the levers 38, these springs drive the plungers into the barrelsuntil the collars 36 strike the regulators and 1 irelie plunger, movement is thereby stopped. It will thus seen that each barrel is completelyfilled at each suction stroke andfthat, by'adwsting the-regulators, the pumps may dis'char e anything from adrop of oil to the fulldisplacement of each'plunger, Owing .tothe comparatively small-difference inpressures, in the reservoir 11 and engine cy inder, the feed pumpsneed not be 'ofvery strong construc- :tion nor need the springs, 40 be very strong;

In this way, much wear-andtear in the feed 7 and measurlng device is eliminated and accuracy thereby obtained; a

The apparatus shown in the drawings is designed to feed two cylinders, but obviously a single reservoir may contain umpsfor all the cylinders of an engine, '9. though preferably the construction is-arranged as illustated and operatesthose cylinders which. fire consecutivelyin a four cylinder or six cylin ,derengine. Preferably the shaft 15 is geared to revolve at half the speed of a four-cycle engine or at the full speed of a two-cycle engine. Obviously for large cylinders which I the latter and" with the injector line to provide for theforcible delivery of fuel from the chamber int'o'saidinjector line and means for maintaining in said chamberand throughout the injector :line a supplyof fuel at a constant normal pressure only slightly below theinjection air or cylinder pressure, said. means comprising a pressure'pump functionin to de 'ver el to the chamber in excess 0 the deliver capacity of the measuring pum and a functioning to prevent the pressure developed in said chamberand in'the injector line by means of the pressure pump from exceeding apredetermined value. g 2.-Fuel"feeding.apparatus for hi h comve can'iedby the fuel cham er and -pr'ess'ion engines comprising a fuel c amber, a measuring pump for delivering fuel from said chamber comprising a cylinder having its inlet connected with-said chamber, a plunger 0 crating in saidcylinder, a lever operative y connected with said plunger, a cam shaft, a cam onsaid shaft cooperating with said lever to operate the plunger in one direction, a spring arranged to operate the plunger in the opposite direction, an abutment on said plunger and-?a tapered member adjustably 3 carried by the reservoir and cooperating with said abutment [to plunger under the p uence of said spring and hiethe stroke ,of the means formaintaining a supply of oil in said reservoir. i

3. Fuel feeding apparatus as recited in claim 2 in which the last mentioned means comprising. a pressure pump including a cylinder having'its outlet connected to said fuel chamber, a plunger operating in said cylinder, a spring arranged to operate said plunger on the suction stroke, and a second cam carried by the aforementioned cam shaft and arranged to operate said plunger on the disl. uel feeding apparatus for high com pression engines comprising a fuel chamber, a

measuring pump for delivering oil from said chamber and a pressure pump for supplying oil to said chamber in excess of the delivery capacity of the measuring pump, each of said pumps including a cylinder having a plunger operating therein, means for placing the fuel. chamber in communication with the inlet of the measuring chamber and the outlet of the pressure pump, a single cam shaft, a pair of cams carried thereby, means controlled by one of said cams for operating the plunger of the measuring pump in one direction, means controlled by the remaining cam for operating the plunger of the pressure pump in one direction, and independent means for operating said plungers in the opposite direction.

5. Fuel feeding apparatus for high compression engines comprising a casing formed with an integral fuel chamber located in the upper portion thereof, a measuring pump having its cylinder located in said fuel chamber and communicating therewith, and a punger operating in said cylinder and projecting below the fuel chamber, a pressure pump including a cylinder located in the casing below the fuel chamber and having its outlet connected the casing above the pressure pump, a cam on said shaft engageable with the pressure pump plunger to move the same downwardly, a.

spring arranged to move the plunger of thepressure pump upwardly when said plunger is free to so move, a lever extending beneath the cam shaft and pivotally mounted at one end and having the other end engaging the plunger of the measuring pump, a second cam on said cam shaft cooperating with said lever to operate the plunger of the measuring pump in one direction, and a spring arranged to operate the plunger of the measuring pump in the opposite direction when the said plunger is free to so move. a 6. Fuel feeding apparatus for high compression engines comprising a fuel chamber, a measuring pump including a cylinder arranged in and communicating with said chamber and a plunger operating in said cylinder and projecting beyond the fuel chamber, means for reciprocating said plunger, a collar fixed to the. projecting portion of the plunger, a pair of spaced guides carried by and extending circumferentially of the fuel chamber at opposite sides of the projecting portion of said plunger, a longitudinally tapered member carried byand slidable between said guides and formed with a central slot re- V ceiving the plunger therethrough, said mem- .,ber being engageable with said collar to regulate the effective delivery stroke of the plunger.

In witness whereof, I have hereunto set my hand.

ANDRE o. ATTENDU,