US2664313A - Fuel injection apparatus for injection engines - Google Patents

Description

. 3 TSURUKICHI ONO 2,664,313

FUEL INJECTION APPARATUS FOR INJECTION ENGINES Filed July 28, 1950 Patented Dec. 29, 1953 UNETED STATES PATENT @FFICE FUEL INJECTION APPARATUS FOR INJECTION ENGINES Tsurukichi Ono, Fukushima-Ken, Japan Application July28, 1950, Serial No. 176,396

3 Claims. (Cl. 299-1075) lhis invention relates to improvements in fuel injection apparatus for an injection engine, such as diesel engine, and more particularly to the structural details of a needle valve therefor, the valve comprising two elements namely a valve body and its push rod which serves to keep said valve pressed against its seat correctly.

It is a particular object of the invention to provide a fuel injection assembly wherein the needle valve has a regular contact with its valve seat during operation. It is a further object of the invention to provide a fuel injection apparatus for a diesel engine, wherein the fuel is atomized completely thus increasing materially the efiiciency of the engine. It is still a further object of the invention to provide a fuel injection apparatus for an injection engine, which is of sturdy construction and which will last much longer than conventional fuel injection apparatus.

The present invention offers a solution of the partial defacement problems of the needle valve and the valve seat. In accordance with the present invention no side pressure occurs between the sliding member and its guide member, namely, the needle valve spindle and its guide, and as the result, the partial defacements of the needle valve and its seat which above mentioned, are positively prevented.

The novel features which we believe to be characteristic of this invention are set forth with particularity in the appended claims. This invention itself both as to its construction and function may be understood by reference to the following description taken in connection with the accompanying drawing in which:

Figure 1 is a longitudinal sectional view of a constructional form of fuel injection apparatus embodying this invention.

Figure 2 is a transversal sectional view taken on the line A-A of Fig. 1.

Figure 3 is a longitudinal sectional view of another modification of this invention.

Referring to Figs. 1 and 2, l is the valve housing having a longitudinal bore 2 and a valve spindle 3 is slidably mounted within the bore. The spindle 3 terminates in a needle valve head 4 which cooperates with a seat 5 provided in the valve housing. At the bottom of the housing I, a fuel chamber ti communicates with the bore 2 at the lower end of the bore. Fuel injection apertures or holes I lead from the space below the seat 5 to a point externally of the housing I. The fuel may be supplied to the chamber 6 through conduits 8 by the use of any suitable type of fuel pump (not illustrated).

' Along its central axis, the spindle 3 is formed with a longitudinal bore 9 which. terminates at its lower end in a concave surface wand the angle of the surface is preferably about 120 degrees. The upper end of the bore is provided with a screw-threaded section l l, by means of which the valve spindle may be removed from the bore 2, when desired. Any convenient type of threaded bar may be employed to engage the threaded section H.

In the bore of valve spindle 3 a push rod I2 is inserted loosely, and the push rod l2 has a conical lower end it supported on the bottom of said bore 9 by its conical end. The end I3 of the push rod engages the surface it in the bore 9 and the angle of the end i3 is approximately degrees.

Therefore, it will be seen that the axis of the push rod coincides exactly with the axis of needle valve and the contacting points of the members will be on said coincided axis. The push rod I2 is provided with an area id of enlarged diameter near the upper end and the periphery of the area it slidably engages the wall of the bore 2 at a point above the spindle 3. At its upper end the push rod is pressed downwardly by a spring as is customary in the art. The spring, through the push rod serves to maintain the valve 4 against the seat 5. The pressure of the spring is less than that of the fuel which is forced into the chamber through the conduits 8.

So when the fuel pump is in action and the compressed fuel has been forced into the fuel chamber through the conduits 8, the needle valve will be lifted from the valve seat upwardly against said spring action, and then the fuel will be injected out from the injection holes I in an atomized state. When the fuel pump has stopped, however, the spring action overcomes the pressure of fuel chamber, so the push rod thrusts the valve spindle through its end 13 resting on the surface ll] of the bore of the spindle thereby urging the valve against its seat.

In accordance with the present invention, the needle valve is pressed on the valve seat only by the conical end it of push rod which contacts with said valve at its concaved conical surface Ill, and as their contact point is on the coincided axis of these two members, the needle valve will fit in its seat exactly.

In conventional apparatus, a single valve spindle is used and it terminates in a valve head and spring means cooperates with the upper end of the spindle to maintain the head against its seat. Thus, a certain amount of side pressure acts upon the spindle when the valve head is moved toward its seat and this pressure is due to the clearance existing between the spindle surface and the inside surface of the bore. This side pressure causes wearing of the spindle, the needle valve and particularly the valve seat.

It is a matter of common knowledge that the partial defacements of the valve and valve seat causes many undesirable phenomena-for the in? jection device, such as supplying unatomizedfuel' to engine, difficulty of repairs and lack of durability etc.

With the present invention, these side. pres. sures do not occur since the spring pressure thrusts only the push rod and the end of the rod presses the valve spindle and as previously men--- tioned, the contact point betwcenthe=rodandthel spindle is on the same central axis of the members.

Therefore, even though the push rod has inclined and diverted from the axis of-valve spin die by the spring pressure, no sidepressure takes place betweenthe valve spindle audits bore or taotingsurfaces which-hold the steel ball 15: are,

both of concave configuration and their angles are about 120.

Theinvention is not limited to the constructional form here shown and described which is, as above stated, given only by way'of example,

as the invention may be performed in. other ways, without departing from its principle. I claim:

1. In a fuel injection. assemblagefor internal combustion engines, a valve body having a fuel.

chamber therein, means defining .a fuel feed .con-

duit in the body leading froma supply source.

to the fuel chamber, fueldischargerports in the body below said chamber andin communication therewith, further means defining an-inverted fIZLIStOr-COYHCBJ valve seatinthe body. intermediatethefuel chamber and the, dischargeports a bore extending longitudinally of the body from one end of the body and merging with the fuel chamber, a valve spindle lodged in and reciprocable in said bore, a conical head on said spindle adapted to cooperate with the wall of the valve seat to open and close communication between the fuel chamber and the discharge ports, the said valve spindle being provided with a bore extending longitudinally fromithe end "remote from the conical head and terminating in a seat, a push rod slidably mounted within the spindle bore with the axis of the push rod coinciding with the axis. of the valve spindle, a spherical objectllodged between the inner end of the push rod and the seat in said spindle defining a contact: area". between, the push rod and the valve spindle, falling, on the axis of the push rod and the spindle, an enlarged area on the said push rod at. a point above the valve spindle of the same diameter as the outer diameter of the valve spindle slidably engagingthewall of the bore in said body to guide, the push rod. within the spindle bore,,and means, operatively asso ciated with said push. rod to maintain, the conical head, of the, valve, spindle, normally in, en gagement with thefrusto-oonical seat.

2; A fuel injection assemblage as, defined in and claimedby claiml further characterizedin that. saidspherical' obj ect'. is, a steel ball.

3..A fuel injection assemblage as dfil1ed in and claimed by claim '1 further characterized in that said push rod is provided with a concave depression in the end thereof and the valve spindleis provided with a concave'seat, the spherical object being lodged between said depression and concave seat.

TSURUKICHI ONO.

References Cited in the file of this patent UNITED STATES PATENTS.

Numb er Name: Date.

1,152,733 Hauser Sept; 7, 1915. 1,761,122 Groif June 3,, 19.36 2,020,666 Veglio Nov..12, 193.5 2,101,682 Klafstad Dec; 7,.1937 2,108,647 Broeze Feb. 15,1938 2,261,461 Falls; Nov. 4,1941

FOREGN PATENTS.

Number. Country Date 491,821 Germany: Feb. 12; 1930'

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