US2743962A - Injection nozzle - Google Patents

Description

May l, 1956 T. M. DREssLER INJECTION NOZZLE Filed Nov. 24, 1954 INVENTOR.

BY f) f www hc 6 7 ,a 3 2 0 ma 5 a@ J i 3 w inw? 2 j 8 3 j, i j 5 M WM- Y lfd AO w i f w I l 1 l n l 1 r l 1 l 5 i ,n :l: 5 ,y I7 7 FLW 2 0,0 1 y, w 5 Q w 1 3 n mm --.u if 5 W M W M United States Patent O il' 2,743,962 INJECTION NOZZLE Thomas M. Dressler, Chicago, Ill., assignor to International Harvester Company, a corporation of New Jersey vThis invention concerns. solid fuel injection nozzle valves of the character employed in fuel injector units for internal -combustion' engines fand which are opened by fuel pressure in the direction of fuel ilow through the valvel into the engine combustion chamber, and more particularly relates to a stop structure settable to selectivelylimit the amount that the valve can open.

`The valve assembly constituting this invention is of the general character of the nozzle valves shown in U. S. Patents 2,433,985 to N, Fodor, and 2,375,492 to E. M. Purdy, et al. The present valve is an improvement over the Fodor patent in the respect of providing an adjustable stop for the valve pintle and is an improvement over the Purdy etal. patentfin the respect of mounting the -adjustable stop on a stationary part of the valve structure and thereby diminishing the mass of parts reciprocal with the valve pintle.

Open type valves of the character with which this invention is concerned employ a valve seat member having a valveseat at one end, a pintle-receiving bore communicating between such valve seat and the opposite end of the seat member,` a pintle having a valve head upon one Vend normally seated against said `valve seat and extending through the valve seat member lbore to place -the opposite or inner end of the pintle in spacedrelation from the inner end of the seatl member to provide for a spring being h eld in compressed relation between the inner end of the pintleand the innerend of the valve seat member to resist axial outward movement ol the pintle through the member bore attendant to unseatingof the pintle head from the valve seat'. iny the nozzle valves of this type it is important that the valve head be displaced from the valve seat a predetermined distance attendant to the valve being opened to control the back pressure in the fuel line and so the spray of the injected fuel will be a predetermined pattern. This type of valve when controlled by a stop so as to open only a predetermined amount, also has the desirable characteristic of permitting a slightly increasedquantity of fuel to flow through the valve when the fuel line pressure impulses created by the fuel pump are of slightly longer duration and less peak pressure with less compression Aof the fuel and less expansion of the fuel line, as is the case in the operation of an internal combustion engine when it is diminished in speed `when encountering a heavy load. This characteristic of the nozzle to admit this slightly increased quantity of fuel responsive to each pumpipressure impulse when the engine slows down under load gives theengine an inherent logging ability.

In addition to the object of ythis invention to provide a variably settable stop mounted independently of the pintle iorlimiting the distance of pintle and valve head movement to predeterminately gauge the distance the valve can open, there are further objectsincluding: the

.provision of a tubular stop member coaxial with the valve pintle and threaded into the inner end of the valve seat member; the provision of a lock-nut upon a threaded portion of the tubular stop member and cooperable with 2,743,962 Patented May l, 1 956 the inner end of the valve seat member for holding the stop member selectively axially spaced from a spring seat on the pintle; the provision of a lock-nut of the above character which also includes means providing a spring seat for an end of the captive spring; and the provision of intermeshed axial projections respectively upon the tubular stop member yand a spring seat at the inner end of the pintle which is provided with wrench-engaging facets facilitating rotation of the spring seat which is operable through the intermeshed projections to rotate the tubular stop member to adjust its axial setting while the interf meshed projections facilitate axial movement of the spring seatmember and the pintle relatively to the stop member attendant to alternate opening and closing of the valve.

The above and other desirable objects inherent in and encompassed by the 'invention are elucidated in the ensuing description, the appended claims, and the annexed drawings, wherein: v

Fig. l is aview taken partly in longitudinal section and partly in side elevation through a fuel injector, and taken in longitudinal section through a nozzle valve assemblyy constructed according to the present invention within the body of such injector;

Fig. 2 is an enlarged longitudinal'sectional view taken through the nozzle valve assembly;

Fig. 3 is an upper end view'of a spring seat member mounted upon the upper end of the valve pintle of the nozzle valve assembly; and

Fig. 4 is an upper end view of a loclonut and spring seat member contained in the nozzle valve assembly.

With continued reference to the drawings, the nozzle valve assembly iii shown isolated in Fig. 2 is mounted within an injector body ll shown in Fig. l. The body ll includes an axial bore l2 having a lower end portion 13 of diminisheddiameter immediately beneath a shoulder 14. A widely flared recess l5 in the lower end of the `injector body provides a ysurface contour compatible with that of the remainder of an engine combustion chamber (not shown) in the wall of which the device is installed to periodically inject a fuel spray Si.

A cylindrical tip portion .lo of a valve seat member' 17 of the valve assembly l0 is inserted downwardly and ts with ay close sliding fit in the injector body bore portion 13. An annular sealing gasket 18 is disposed between the annular shoulder i4' and the lower end of a cylindrical llange i9 of the valve seat member 17. A second annular sealing gasket 2l is placed on top of the upper end of the llange 19 between such flange and a tubular spacer member 22 which has a sealing gasket 23 fitted between its upper end and the lower end of a tubular stem 2d of a fuel conduit coupling member 2S..

Fuel admitted into the coupling member 2S through a tapped hole 26 thereof flows downwardly through a bore 27 in the tubular stem 24 and thence through a filter element 28 into a fuel chamber 29 from which ejection of this fuel from the valve tip 16 is controlled by the injector nozzle assembly Zlib. The parts including the nozzle assembly valve seat member i7 which are in stacked relation within the injector body bore 12 are compressed firmly in such bore by capvscrews 3l of which Shanks 32 extend downwardly through holes 33 in the cross head 34 of the coupling member 25 into threaded holes 36 in the upper end of the injector body 11.

The lower outer end ofthe valve seat member 17 contains va conical valve seat 37. A pintle-receiving bore 38 v extends upwardly communicatively from this seat throughv the upper inner end of thefvalve seat member. An enf larged diameter upper portion 39 of the bore 38 is seat member 17 to retain the tubular stop member in a selectable axial position relatively to such seat member. The lock nut 43 which is hexagonal to provide wrenchengaging facets 45 also has an axially projecting annular flange 46 which adapts the nut to function as a seat for the lower inner end of a spring 47.

Spring seat means for the upper outer end of the spring 47 is in the form of a member 48 having a square periphery, as shown in Fig. 3, to provide wrench-engaging facets 49. Rounded corners 50 of this periphery slidingly bear against the inner periphery of the sleeve 22 to pilot the upper end of a pintle 57 of the assembled device. A keyhole opening 51 extending axially through the member 48 has a central seat portion 52 communicating with a hole-like portion 53 of greater diameter than the width of such seat portion. A diametric groove 54 is formed in the lower end of the spring seat member 4S. This groove is for receiving axial projections 55 upon the upper end of the tubular stop member 42. When the nozzle valve is assembled, as shown in Fig. 2, the axial projecting portions 56 formed by groove S4 on the lower end of the valve seat member 48 axially mesh with the projections 55 of the tubular stop member whereby these projections are adapted to transmit turning force to the tubular stop member for rotatively adjusting the same in the threaded portion 41 of the valve seat member 17, a wrench being engaged with the spring seat facets 49 for rotating the spring seat and the tubular stop member.

The pintle 57 has a valve head 58 on its lower inner end normally seated against the valve seat 37. A stem 59 of this pintle extends upwardly from the head 58 through the bore 38 and the tubular stop member 42 and is of a length to dispose a stem enlargement 61 above the inner end of the stop member. enlargement 61 of the pintle 57 is placed in registry with the opening portion 53 through the valve seat member 48 while the latter is forced downwardly to compress the spring 56 and insert the enlargement 61 through the registered opening portion 53, subsequent to which the seat member 48 is moved laterally to carry the enlargement 61 into registration with the seat 52 where such enlargement is retained by force exerted on such member by the then captive spring 46.

Each time the liquid fuel in the chamber 29, Fig. l, is subjected to a pressure impulse from the fuel pump (not shown) fuel is forced to ow downwardly through the opening portion 53 in the valve seat member 48 and thence downwardly in the clearance space between the pintle and the tubular stop member 42 and into the space between the pintle and the valve seat member bore 38 where the pressure of fuel against that portion of the valve head 48 extending radially inwardly from the valve seat to the pintle stem 59 is built up sufficiently to force the valve head 58, the pintle stem 59 and the spring seat member 4S downwardly, permitting fuel to escape in the form of the conical spray pattern SP.

The distance the valve head is displaced from the seat 37 is determined by abutment of the spring seat projections 56 with the upper end of the tubular stop member 42. This distance is determined before insertion of the nozzle valve assembly 1t? into the injector body 11, but subsequent to fabrication of the assembly into the condition illustrated in Fig. 2. While the stop nut 43 is loosened, the spring seat member 48 is rotated for screwing the tubular stop member 42 upwardly until the upper end of the tubular stop member abuts against the projections 56 of the member 48 which condition would prevent the pintle 59 moving downwardly and thereby prevent the valve head 58 departing f rom the seat 37. The assembly is then in condition to have the stop member 42 selectively set, and this is done by rotating such In assembling the device the member by means of a wrench applied to the facets of the spring seat member 48 in the direction to advance the stop member downwardly from the projections 56. The amount the tubular stop member is rotated will, of course, depend upon the pitch of the threads 41 and 44, but a typical thread pitch attains a typical spacing of the stop member from the spring seat member 48 when the stop member is rotated one-fourth turn. When this is accomplished a wrench is applied to the spring seat lock nut 43 for turning it on the threads 44 until this member 43 is engaged tightly against the upper inner end of the valve seat member 17.

Having described a single preferred form of the invention with the view of clearly and concisely illustrating the same, I claim:

l. In an injection nozzle, a seat member having inner nd outer ends, an outwardly facing valve seat at the outerl end and a bore communicating between said seat and theinner end of such member, a portion of said bore adjacent the inner end of the seat member being threaded; an elongated valve pintle having inner and outer ends with a valve head upon the outer end thereof cooperable with said seat, and a shank of less transverse area than said bore extending from the valve head inwardly through said bore beyond the inner end of the valve seat member, the pintle being axially retracted while the head is on the valve seat but being axially advanceable under the influence of liquid fuel pressure in said bore upon the head to lift the head from said valve seat; spring vseat means upon the inner end of said pintle in spaced relation axially thereof from the inner end of the valve seat member; a coiled axially compressible spring coaxially about the pintle and held captive under compression between the spring seat means and said valve seat member for urging the pintle endwise retractively to press the valve head against the valve seat; a tubular valve stop member exteriorly threaded and screwed into the threads of the seat member bore concentrically about the pintle, said stop member extending from the valve seat member into spaced proximity with the spring seat means for engagement thereby to limit endwise advancement of the pintle attendant to lifting the valve head from the valve seat, said stop member being rotatable in the threaded bore portion to selectively determine the proximity thereof from the spring seat means of the retracted pintle; axially intermeshable elements respectively upon the ends of the spring seat means and the tubular stop member, said meshable elements being adapted to transmit rotary movement to the tubular stop member from the spring seat means while being also adapted to accommodate axial reciprocation of the spring seat means relatively to the stop member; and a spring seat member interposed between said spring and the inner end of said valve seat member and containing a threaded bore surrounding the tubular stop member and turned onto the threaded portion of said stop member to adapt said spring seat member to serve as a lock nut cooperable with the valve seat member for retaining the tubular stop member in selected axial adjustment.

2. The combination set forth in claim l wherein the spring seat means and the spring seat member each have wrench-engaging facets upon their radially outer peripheries.

References Cited in the file of this patent UNITED STATES PATENTS 1,822,668 Protzteller Sept. 8, l93l FOREIGN PATENTS 759,151 Germany Nov. 2, l953 790,001 France Sept. 2, 1935

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