US1867700A - Fuel feed system - Google Patents

Description

July 19, 1932. G. l., JONES FUEL FEED SYSTEM Filed Aug. 3l, 1925 H M J 2. c llsV, -ull 7d I 2.5.5/ Mwum'`\\\\\\\\\\\"w 5 Z y//g 9W ad 1J l fr .410, E: 7,

l L. i#@ w 5 u 3 7 bggggfs. l

Patented July 19, 1932 UNITED STATES PATENT oFFlcE GEORGE LESTER JONES, OF BROOKLYN, NEW YORK,- ASSIGNOR TO SPERRY DEVELOP- MENT COMPANY, OF DOVER, DELAWARE, A CORPORATION OF DELAWARE FUEL FEED s YsrEm:

Application led August 31, 1925. Serial No. 53,537.

This invention relates to fuel injection systems for internal combustion engines and has for its principal object the provision of a system characterized by the absence of the high pressures, in many cases up to several thousand pounds per sq. in., which usually prevail in such systems. As a consequence a comparatively cheap construction maybe employed as compared with the fuel injectlon l@ systems now used in the art. It is a further object of this invention to provide a fuel 1njection system wherein the so-called after drip is eliminated, that is, wherein the 1njection is cut off sharply rather than by l5 gradual diminution so that the fuel supply.

is likewise cut off sharply without any oversupply of fuel.

I accomplish the above objects by utilizing the principle thatwhere a rapidly flowing fluid in a closed system is suddenly stopped there is generated a relatively large reaction pressure of approximately 57 lbs. per sq. in. for each foot per second velocity. By impartting to the fuel a sufficiently high velocity, almost any desired reaction pressure may be obtained.

Further objects and advantages of this invention will become apparent in the following detailed description thereof.

rThe accompanying drawing. is an assembly view, with parts sectioned vertically, of a fuel injection system embodying one form of my invention.

Referring to said drawing I have shown a combustion cylinder 10 having a fuel inlet 11 controlled by a fuel inlet valve 12 in the usual manner. That is to say, periodically said valve is raised and fuel, under relatively great pressure, frequently several thousand pounds per square inch, is introduced.

I supply fuel under pressure to said valve by way of a conduit 14 and create said pressure by the following system. Fuel may be stored in al sump or reservoir 20 from which it may be drawn through a conduit 21 by some mea-ns, such as a rotary or centrifugal pump 22 capable of imparting relatively high velocity to said fuel which is then transmitted through a closed system 23-24 back to the reservoir. The fuel supply conduit 14, it

will be observed, forms a branch of the said closed system. For supplying the fuel to said fuel supply conduit 14 under the requisite high pressure, I provide means for converting into pressure the relatively high velocity imparted to the fuel by pump 22. For

this purpose I provide within the closed pumping system an interrupting mechanism, such as interruptor valve 30, normally pressed toward engagement with its seat 31 by means, such as a spring 32. The tension of said spring may be varied in the usual manner by a threaded nut closure 33. The valve is normally held raised above its seat by a latch or dog 35 engaging under a lever 36 pivoted to a fixed support or bracket at 37 which has pivoted thereto at 38 intermediate its length the stem 39 of the valve 30. vLatch 35 is normally held in engagement beneath lever 36 by means such as a spring 40. With the valve raised from its seat, it will be observed that the closed pumping system operates continuously without generating any substantial pressures in the fuel injection system.

In order to generate the necessary pressure, i provide means for periodically unlatching the latch 35 to permit spring 32 to seat the valve, thus closing the pumping system and abruptly stopping the flow of fluid. Back pressure thus created would pump fuel back through conduit 14 to the fuel inlet valve. The said back pressure is prevented from acting upon the velocity-imparting means 22 by means such as a one-way ball valve 45 located between the valve 30 and the pump 22. It will be understood that the closing of the interrupter 30 is timed to correspond with theperiods of opening of the fuel. inlet valve, so that .the back pressure thus created causes Vfuel to be supplied to the fuel inlet valve and discharged therefrom into the combustion space of the cylinder. For unlatching the latch 35 periodically, I may provide upon a rotating shaft 46 a dog 47 adapted to engage said latch to swing the same about its pivot 48 and thus release lever 36. Spring 32 will then immediately seat valve 30 upon the valve seat 31. Also fixed to said shaft 46 is a cam 49 which is so positioned relative to dog or detent 47 as to raise the vided a fuel injection system wherein sufii' ciently large pressures are created without subjecting the closed system and pump to sufficient strain to necessitate an expensive and complicated structure, such as is now required to withstand the great pressures generated. The form of pump used may be of much simpler construction and much less expensive than the present type known to the art. Also, that by the positive closing and opening of valve 30, the amount of fuel injected is predetermined and there is hence no after-drip which lowers the,- efficiency and causes waste of fuel.

In accordance with the provisions of the patent statutes, I have herein described the principle and operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof, but I desire to have it understood that the a paratus shown is only illustrative and that t e invention can be carried out by other means. Also, while it is designed to use the various features and elements in the combination and relations described, some of these may be altered and others omitted without interfering with the more general results outlined, and the invention extends to such use.

Having described my invention, what, I claim and desire to secure by Letters Patent 1s:

1. In a fuel supply system, a source of fuel supply, a fuel injection valve, means for imparting velocit)T to the fuel, means for suddenly stopping the flow of fuel, and means for utilizing the reaction pressures thus generated for injecting fuel through said valve, said last named means including means for breaking the connection between said first means and said stopping means when the latter is rendered effective.

2. In a fuel supply system, a source of fuel supply, a fuel injection valve, means for imparting velocity to the fuel, means for suddenly stopping the flow of fuel, means for utilizing the reaction pressures thus generated for injecting fuel through said valve, said last named means including means responsive to said reaction pressures for breaking the connection between said first means and said stopping means when the latter is rendered effective.

3. In a fuel supply system, a source of fuel supply, a fuel injection valve, means for imparting velocity to the fuel, means for suddenly stopping the flow of fuel, means for utilizing the reaction pressures thus generated for injecting fuel through said valve, said last named means including a checkvalve responsive to said reaction pressures for breaking the connection between said first means and staid stopping means when the latter is rendered effective.

4. In a fuel injection system for an engine, a source of fuel supply, means for imparting velocity to the fuel, means for suddenly stopping the flow of fuel, and means whereby the fuel is injected into said engine solely by the reaction pressure thus generate 5. Ina fuel injection system for an engine having a fuel injection valve, a source of fuel supply, means for imparting velocity to the fuel, means for suddenly stopping the iow of fuel, and means whereby injection of the fuel through said valve is accomplished solely by the reaction pressure thus generate 6. In a fuel injection system for an en- 'ne having a fuel injection valve, a source of ilel supply, means for imparting Velocity to the fuel, means for periodically suddenly stopping the flow of fuel, and means whereby injection of the fuel through said valve is accomplished solely lby the reaction pressures thus generated.

In testimony whereof I have affixed my signature.

GEORGE LESTER JONES.

Images