US2777431A

US2777431A - Injection nozzle arrangement

Info

Publication number: US2777431A
Application number: US452359A
Authority: US
Inventors: Meurer Siegfried
Original assignee: MAN Maschinenfabrik Augsburg Nuernberg AG
Current assignee: MAN AG
Priority date: 1953-08-28
Filing date: 1954-08-26
Publication date: 1957-01-15
Anticipated expiration: 1974-01-15

Description

INJECTION NOZZLE ARRANGEMENT 2 Shets-Sheet 1 Filed Aug. 26, 1954 IN VENTOR Fey/med Meur'er' a d ATTONEYJ Jan. 15, 1957 s. MEURER INJECTION NOZZLE ARRANGEMENT 2 Sheets-Sheet 2 Filed Aug. 26, 1954 INVENTIOYRN Jz'eyf/"l'ed Meurer %,M 2 Mala;

ATTORNEYS United States Patent" 2,777,431 INJECTION NUZZLE ARRANGEMENT Siegfried Meurer, Numberg, Germany, -assignor to Maschin'enf'ahrik Augsburg-Numberg A. G'., Nurnberg,

Bavaria, Germany, a firm ApplicationAugust 26, 1954,1Serial No. 452,359 Claims priority, applicationGermanyAngust 23, 1953 8' Claims. (Cl. 12332-)- Insmall high speed engines, however, the nozzles are toosmall to permit such cooling.

It is an object of the persent invention to provide an arrangement ensuring an efficient heat transfer from the nozzle to the surrounding parts so as to keep the nozzle temperature at a low figure.

A special object :of the invention is to provide an arrangement in which the nozzle surf-ace exposed to the hot gas is reduced to a minimum and an intimate heattransmitting engagement is ensured between the nozzle and its holder under all operating conditions and irrespective of different thermal expansion of said parts.

Another object of the invention is to provide an arrangement permitting easy mounting of the nozzle and avoiding distorting stresses therein.

With these and other objects in view, this invention consists in the details of construction, combination of elements and operation hereinafter set forth and then specifically designated by the claims.

In order that those skilledin the art to whichv this invention appertains may understand how tomake and use the same, I will describe its constructionin, detail, referring by numerals tothe-accompanying drawings formingzpart of this'application, inwhich:

Fig. 1' is a sectional viewof anarrangement having the invention applied thereto,

Fig. 2 is -a detail thereof,

Figure 3 is a sectional view similar to Fig. 1, showing a modified form,

Fig. 4 is a view similar to Figs. 1 and 3, but showing a-further modification, and

Fig. 5 is a view similar to Fig. 4, showing a still'further modification.

:transfe-r member even at difierent thermal expansion of the parts.

This is exemplified in Fig. 1, showing a nozzle holder 1 and a nozzle'-comprising a main body 3, aistem 3, a needle valve 36,. with its extension 32, and a nozzle tip 4 with the atomizing bores (not shown), secured to the.

nozzle holder '1 by a cap nut 2 thread'ably engaged on a male thread of the nozzle holder The needle 30 is exposed to the pressure of aspring "(not shown)v through a; "round pressure rod 34 and. apressure-transmittingball 35 seated in a recess of the rod-34 and engaged by an:

I in a cold condition.

upper projection 32' of the extension 32 of the needle valve 30, as shown. The fuel is admitted through a channel 33, 33' in the members3 and 1. Mounted on the noz-v v The intermediate member 8 is elastic or resilient in an axial direction, preferably by the provision of slots' 8, Fig. 2.

It will thus be understood that the'conicalpacking memher 5 can be slipped onto the cylindrical nozzle stem 3 By way of alternative, the nozzle stem 3: may also be conically shaped.

The arrangement illustrated operates as follows:

As the'cylinder head 6 and the

nozzle

3, 3" are heated during operation of the engine, thepacking body 5, having a larger thermal expansion than the nozzle stem 3', tends to expand, this tendency being opposed in the direction of the nozzle holder by the resilient member 8. Owing to the conical seat of the packing body 5 in the bore 7 the body 5 isforced toexpandradially inwards, in sucha Way that the fit between the stem 3' and the membr 5 becomes a grip fit, the amount of specific pressure being determined by the resiliency of the. member 8 andthe slope of the cone 5 in the cylinder head 6, in such a way that deformation of the nozzle is avoided.

The tightengagement of the packing surfaces between the nozzle stem 3 and the conical packing body 5 on the one handand between the latter and the. cylinder head 6 is thus improved as a result of the thermal stresses. Therefore, the fuel gas is safely prevented from entering between the packing-body 5 and the nozzle stem 3. and

from heating the parts in entering therebetween-and the transfer of heat from the nozzle stem 3' through the packing body 5 to. the cooled cylinder head 6isfiacilitated packing body 5 will be retained in the cylinder head,

by the higher specific surface pressure between the adjoining surfaces.

If the nozzle is dismantled in a hot condition of the engine, the packing body 5 will be removed from-the cylinder head 6 together with the nozzle 3, 3', in view of the grip fit between the

members

5 and 3, in a hot condition. 011 the other hand, if the nozzle is removed with the cylinder head 6 in cold condition, the conical so-that the

nozzle

3, 3 can be withdrawn from the member 5.

According to a modified form of the invention the conical packing body is provided with a sleeve-shaped extension which in the built-in condition of the nozzle is washed by the cooling Water circulating in the doublewalled cylinder head, for ensuring antefiicient cooling.

According to a still further feature of the invention, the conical packing body may be designed inpsucha: way that it retains the nozzle stem after the manner. of. a chuck, whereby deformations or distortion stresses of the nozzle can be easily avoided, without requiring a high accuracy ofmanufacture. Thus, an elastic sleeve member such as that provided at 3 in Fig. 1 for compensating possible. inaccuracies is not required.

An arrangement of this kind is illustrated in Fig. 3', the extension being shown at 11 In order to prevent. the cooling water from entering into thecylinder 6 wh'ei1 removing the

nozzle

3, 3 the: packing inemberS is exposed toa preliminary pressure by the ring mu T4 through the extension n and a further intermediate 'sieeve 1a, the

Patented Jan. 15, 1957 i packing efiect at 10 again being ensured by tight engagement between the cap nut 2 and the upper face of the packing body 5, said engagement being caused by the nozzle holder 1 in a manner not shown in detail.

Additional packing rings

15 and 16 may be provided between the

parts

11 and 13, or 13 and 14, respectively.

A still further and preferred modification is exemplified in Fig. 4. Again, the packing cone 5' is formed with an extension 17, which in this case projects into the nozzle holder 1, for urging the cone 5 into the conical seat 7 1 of the cylinder head 6 by the ring nut 9 through an intermediate disc 18 and an expanding ring 19, which may be a spring ring or a bipartite ring. The bore in the cone 5 is thus contracted, so that the nozzle stem 3 is clamped as in a chuck. The gas-tightness in this case is ensured already by the pressure between the nozzle stem 3' and the packing cone 5 and faulty gripping of the nozzle holder 1 and the nozzle cannot occur, since the nozzle holder, the same as in Fig. 3, automatically adjusts itself strictly in accordance with the bore in the packing cone 5. However, as distinguished from Fig. 3, additional means in the form of intermediate rings or a helical spring 2d are provided to prevent the nozzle holder 1 from being inadvertently forced out of the bore, said rings or helical spring 20 engaging the cap nut 21 if the gas pressure should tend to force the nozzle body 3 outwards owing to a possible too loose connection erroneously existing between the members 5 and 3'. A rubber ring 21 prevents the cooling water from entering into the cylinder when dimantling the nozzle. The conical seating surface of member 3 is subdivided into two or more ring surfaces by the provision of one or more turned-in annular grooves 22, whereby the adaptation between the cone 5 and the conical bore 7 is improved without impairing the gas-tight seal or the heat transfer.

The spreader or expanding ring 19 which is free to move axially in its recess 19a in the cylinder head 6 in an axial direction towards the nozzle, but held against such axial movement in an opposite direction, prevents the cone member 5 from being inadvertently withdrawn from the cylinder head 6 in an upward direction when withdrawing the nozzle holder 1.

It will thus be understood that in the embodiment shown in Fig. 4 the cone 5 is positively pressed onto its seat 7 through the

parts

9, 18, 3.9, 17, and additionally it is nonpositively pressed onto its seat 7 through the

members

9, 20, 2 and the engagement at 10.

If the ring nut 9 is removed, for withdrawing the nozzle, only the member 20 and possibly, but not necessarily, the ring 13, will take part in such withdrawing movement, while the expanding ring 19 remains in its position, or engages the shoulder formed at the end of the recess 19a, respectively, thus retaining the member 17 and the cone member 5 in position. Hence, even when withdrawing the nozzle, cooling water can never penetrate into the combustion chamber.

In the modification shown in Fig. 5 a separate member 17' is seated in a cylindrical stepped bore in the cylinder head 6 and held in its position by axial pressure exerted by a threaded ring 9, through

rings

18 and 19. The conical member 5 in this case is seated in a complementary conical bore 7 in the sleeve 17 under the axial pressure exerted by a resilient member 20, more particularly, a helical spring, in such a way that the nozzle stem 3 again is held therein as in a chuck. Thus, it is possible to unscrew member 9 for removal of members 20, i, 2, 3, 5, while ring 19 remains in its position and retains the member 17', so that the cooling water is safely prevented from entering into the cylinder. It will be appreciated that a very effective cooling of the nozzle is ensured in this case together with a simple construction and method of assembling and dismantling the parts.

While the invention has been described in detail with respect to certain now preferred examples and embodiments of the invention it will be understood by those skilled in the art after understanding the invention that various changes and modifications may be made without departing from the spirit and scope of the invention and it is intended, therefore, to cover all such changes and 'lOdlfiCZl'ElOllS in the appended claims.

I claim:

1. A cylinder head and injection nozzle arrangement for internal combustion engines, comprising a cylinder head, steeply tapered conical nozzle bore means in said cylinder head, an injection nozzle including a nozzle stem, a similarly tapered conical packing body of a higher thermal conductivity than said injection nozzle surrounding said injection nozzle and adapted to be freely slipped on the nozzle stem in a dismantled condition and being 'llush with the free end of said nozzle stem, and resilient means for forcing the conical packing body into said conical nozzle bore of the cylinder head, in such a way that the conical packing body in an assembled condition fits tightly in the conical bore of the cylinder head and when heated fits tightly on the nozzle stem.

2. A cylinder head and injection nozzle arrangement for internal combustion engines, comprising a cylinder head formed with a conical nozzle bore, an injection nozzle including a nozzle stem, a nozzle holder, :1 conical packing body of a high thermal conductivity adapted to be freely slipped on the nozzle stem in a dismantled condition, and means including an axially resilient mernher for transmitting axial forces onto the conical packing body for forcing said body into said conical nozzle bore of the cylinder head, in such a way that the conical packing body in an assembled condition fits tightly in the conical bore of the cylinder head and on the nozzle stem.

3. An arrangement as in claim 1, further comprising a cooling water chamber in said cylinder head communicating with said tapered conical nozzle bore, and a sleevelike extension on said packing body reaching into said cooling chamber to be washed by the cooling water therein.

4. An arrangement as in claim 3, said resilient means further comprising a force-transmitting sleeve engaging said sleeve-like extension.

5. An arrangement as in claim 1, a cooling water chamber in said cylinder head surrounding said resilient means, said resilient means further comprising a sleevelike extension on said packing body, a nozzle holder mounted in said cylinder head and being surrounded by said sleeve-like extension, and means for exerting an axial pressure on said extension to effect a chuck clamping of said nozzle stem by said packing body.

6. An arrangement as in claim 5, said exerting means further comprising a ring nut threaded to said cylinder head and surrounding said nozzle holder, and elastic means mounted between said nut and the end of said sleeve-like extension.

7. An arrangement as in claim 6, said elastic means further comprising an expanding ring.

8. An arrangement as in claim 1, further comprising a cooling water chamber in said cylinder head surrounding said injection nozzle, a nozzle holder engaging said packing body, a ring nut threaded to said cylinder head, said resilient means being interposed between said ring nut and said nozzle holder and a sleeve having a conical end seated in said conical bore means and surrounding said packing body and extending into contact with said ring nut.

References Cited in the file of this patent UNITED STATES PATENTS 1,653,287 Johnson Dec. 20, 1927 2,080,189 Schwaiger May 11, 1937 2,144,861 Truxell Jan. 24, 1939 2,322,606 Ward June 22, 1943 2,560,799 Johnson July 17, 1951