US2839000A

US2839000A - Fuel injection device

Info

Publication number: US2839000A
Application number: US409609A
Authority: US
Inventors: Faust Josef
Original assignee: Kloeckner Humboldt Deutz AG
Current assignee: Kloeckner Humboldt Deutz AG
Priority date: 1953-02-14
Filing date: 1954-02-11
Publication date: 1958-06-17
Anticipated expiration: 1975-06-17
Also published as: AT185615B; GB754223A

Description

June 17, 1958 J. FAusT 2,839,000

FUEL INJECTION DEVICE Filed Feb. 11, 1954 s Sheets-Sheet 1 F/G. I

//V VENTOR 2/:10/ ift b/ J1me 1958 J. FAUST 2,839,000

FUEL INJECTION DEVICE Filed Feb. 11, 1954 3 Sheets-Sheet 2 Winn.

QdLQA June 17, 1958 Filed Feb. 11, 1954 J. FAUST FUEL INJECTION DEVICE 3 Sheets-Sheet 3 United States. PatentO FUEL INJECTION DEVICE Josef Faust, Sieghurg, Germany, assignor to Kliickner- Humboidt Deutz Airtiengesellschaft, Koln-Deutz, Ger

many 1 Application February 11, 1954, Serial No. 409,609

Claims priority, application Germany February 14, 1953 3 Claims. (Cl. 103-5) The present invention concerns a fuel injection device and, more particularly, relates to a fuel injection device for internal combustion engines in which an ejector actuated by the overflow fuel of the injection pump acts as feeding pump, and in which the overflow conduit of the fuel injection pump is, in a manner known per se, separate from the intake conduit.

Witha heretofore known fuel injection device of the above mentioned type, a nozzle serves as ejector, which nozzleconcentrically leads into a diffuser having an inner circular cross section. The manufacture of such ejector causes considerable difficulties in view of the precision required because its efficiency is already considerably affected if, for instance, the nozzle is not precisely concentrically arranged with regard to the diffuser.

It is an object of this invention to provide a feeding means for a fuel injection device of the above mentioned type which will be considerably simpler in construction and easier to manufacture than the correspondingfeeding means heretofore known in connection with such fuel injection device.

It is a further object of this invention to provide a fuel injection device of the type set forth above which willrequire considerably less space than fuel injection devices as heretofore known for similar purposes, and which'will not require the employment of feeding nozzles.

These-andother objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawings in which: I

Fig. 1 is a diagrammatic representation of a fuel injection installation according to the invention. I

Fig. 2 illustrates on a larger scale than Fig. l the connection of feeding means according to the invention with a fuel filter shown inFig. 1.

General arrangement The feeding means according to the present invention is characterized primarily in that one or more passages or channels for conveying the overflow fuel lead into the feeding conduit means at an acute angle so that the desired flow as well as the desired direction of flow will automatically be obtained in the said feeding conduit means so that neither nozzles nor diffusers in cooperation with nozzles will be required.

The effect of this feeding means or feeding device is based on the fact that each time a short severe pressure shock is being produced in the fuel injection pump by the overflow of the fuel, a pressure wave will be produced in that section of the feeding conduit means which is adjacent to the feeding-in range in the feeding direction. 7 This pressure wave, putting into motion the liquid 2,839,000 Patented June 17, 1958 IC C 2 in said conduit section, acts like a piston and draws with it liquid from the space preceding the feeding-in range.

According to a particularly advantageous arrangement in conformity with the invention, the passages or channels which conveythe overflow fuel lead into the feedingconduit means at an angle of less than 30".

In order to prevent an interruption in the delivery fiow of the fuel in the feeding conduit means during the intervals between the overflow-periods of the feeding pump, the feeding conduit means isdesigned so long that the inertia effect of the fuel contained therein will overcome the said intervals between the overflow periods. The ratio of the length of thatsection of the feeding conduit means which follows the feeding-inrange for the overflow fuel with regard to the inner diameter of this section of the conduit means preferably amounts to at least :1; Furthermore, also the ratio of the cross section of the mixing distance following the feeding-in range with regard to the feeding-in cross section of the overflow fuel is of importance. A ratio of 3:1 has been found'to yield good results.

The feeding-in of the overflow fuel may be effected directly into the feeding conduit means or according to a still further development of the invention may be effected within a special feeding element which is built into the feeding conduit means and is provided witha connection for the overflow fuel. ,The said feeding element'consists primarily of a body within which the feeding-in of the overflow fuel is effected into a bore leading off from the entrance opening for the fuel to be delivered, and of a preferably coil pipe which connects the said bore with the fuel exit opening.

If desired, also other auxiliary means such as check valves, adapted to increase the efficiency may be incorporated in the feeding device. Thefeeding device is preferably directly connected to the fuel filter or to the fuel injection pump. The coil pipe when forming a component of the feeding device is preferably mounted in a recess provided'in the casing of the fuel filter or the fuel injection pump.

The installation in a small chamber of such a section of the conduit means as is required' for a good effect, for instance by winding such section in form of a coil or by enclosing the conduit section in a-casing of the fuel filter or fuel injection pump, hasthe advantage that a damaging of such condiut section will be prevented and, when' repairing the device, a replacement of such conduit section by' a shorter section will be obviated.

Structural arrangement Referring now to the drawings in detail and Fig. 1 thereof in particular, the arrangement shown therein comprises a fuel reservoir 18 from which the fuel passes through conduit 19, a valve'13, a filter 20, and a conduit 21 into the cylinder 16 of a fuel injection pump 17 After the piston upper edge 22 of the fuel injection pump 17 has closed the mouth of the suction conduit 21, the fuel injection pump 17 feeds fuel through the pressure or check valve 23 and pressure conduit 24 through the intervention of the fual injection valve 25 into the combustion chamber of an engine. The fuel injection is completed as soon as the control edge 27 of the piston of the fuel injection pump 17 releases the mouth of the overflow conduit 15 in the fuel injection pump 17. The overflow conduit 15 leads at 29 at an acute angle a of preferably 30 into the suction conduit 19.

As will be evident from Fig. 1, the overflow conduit 15 feeds into the suction conduit 19 ahead of the filter 20 when looking in the direction of flow of the fuel to the injection pump 17.

In conformity with the specific showing of Fig. 2, the feeding in of the overflow fuel is effected within a special feeding element or block 1. The inlet opening 2 of the arrangement shown in Fig. 3 is connected to the conduit 19 shown in Figs. 1 and 2. The discharge opening 3 in the arrangement of Fig. 3 for the fed fuel is connected to the conduit 21 shown in Figs. 1 and 2.

The openings 2 and 3 are interconnected through a bore 4 (Fig. 3) having one end adjacent to and in communication with the opening 2 and having its other end connected to a coil pipe 5 communicating with the opening 3. The fuel passed into the feeding device from the fuel injection pump through the overflow 15 (Figs. 1 and 2) flows into block 1 through an opening 6 (Fig. 3) and from there passes through an oblique channel 7 into the bore 4 and from there into the coil pipe 5. Due to the pressure waves which occur within theifeeding-in range of the bore 4 and which continue into the coil pipe 5, liquid is intermittently drawn in from the intake opening 2. A flowing back of the liquid into the feeder conduit 9 which is connected to the block 1 by means of a hollow screw 8 and nut 8a is prevented by a check valve 10 arranged in said hollow screw.

Fig. 4 diagrammatically illustrates a portion of a fuel injection installation according to the invention with the feeding means mounted directly on the fuel injection pump. In Fig; 4, the tank is again designated with the reference numeral 18 and furnishes fuel through conduit 19 and block 1 into the coil 5 similar to the arrangement of Figs. 2 and 3. The overflow conduit is designated with the reference numeral 15, while the filter is again designated with the reference numeral 20.

The operation corresponds to that described in connection with Figs. 1 to '3.

It is, of course, understood that the present invention is, by no means, limited to the particular arrangement shown in the drawings but also comprises any modifications within the scope of the appended claims.

What I claim is:

1. In combination in a feeding arrangement for use in connection with a fuel injection pump having a fuel intake opening and an overflow opening and being arranged for supplying fuel to an internal combustion engine: a fuel reservoir, a body provided with first conduit means, a fuel filter having a casing with a recess therein and also having an inlet connected with said fuel reservoir, said fuel filter also having an outlet connected with one end portion, of said first conduit means for conveying fuel thereto, said body being provided with second conduit means having one end portion thereof connected to said intake opening of said pump for discharging fuel thereinto, connecting means effecting communication between the other end portions of said first and second conduit means, said connecting means being formed by coiled conduit means mounted in said recess of the casing of said filter, and third conduit means having one end portion thereof connected to said overflow opening for receiving overflow fuel from said fuel injection pump and having its. other end portion leading into said first conduit means at an acute angle with re- 'gard to the longitudinal axis of said first conduit means so that the legs of said angle open in a direction opposite to the desired direction of flow of fuel in said first conduit means toward said fuel intake opening.

2. In combination in a feeding arrangement for use in connection with a fuel injection pump having a casing with a recess and also having a fuel intake opening and a fuel overflow opening for supplying fuel to an internal combustion engine: a body provided with first conduit means arranged for connection with a fuel reservoir, said body also being provided with second conduit means including a discharge opening for discharging fuel to be delivered to said fuel intake opening, coiled conduit means arranged in said recess of the casing of said fuel injection pump and effecting communication between said first and said second conduit means, and third conduit means having one end portion thereof arranged for connection with said overflow opening for receiving overflow fuel from said fuel injection pump and having its other end portion leading into said first conduit means at an acute angle with regard to the longitudinal axis of said first conduit means so that the legs of said angle open in a direction opposite to the desired direction of flow of fuel in said first conduit means toward said fuel intake opening.

3. In combination in a fuel injection device: a fuel injection pump having a fuel intake opening and a fuel overflow opening, an ejector associated with said injection pump and operable as a feeding pump by the overflow fuel of said injection pump, delivery conduit means having one end arranged for connection with a fuel supply and having its other end arranged for connection with the fuel intake opening of said fuel injection pump, and additional conduit means having one end portion thereof connected to said fuel overflow opening for receiving overflow fuel from said fuel injection pump and having its other end portion leading into said delivery conduit means at an acute angle with regard to the longitudinal axis of said delivery conduit means so that the legs of said angle open in a direction opposite to the desired direction of flow of fuel in said delivery conduit means toward said fuel intake opening, the ratio of the length of the delivery conduit means following in the direction of flow the feeding-in point of said additional conduit'means into the delivery conduit means to the inner diameter of said section being at least :1.

References Cited in the file of this patent UNITED STATES PATENTS 1,958,354' Stephens May 8, 1934 2,230,201 Hermann Jan. 28, 1941 2,263,913 Bargeboer Nov. 25, 1941 2,297,681 Anderson et al. Oct. 6, 1942 2,495,685 Beaman Jan. 31, 1950 2,657,637 Baker Nov. 3, 1953 FORElGN PATENTS 49,609 Austria of 1909 382,592 Great Britain Oct. 27, 1932