US3159350A

US3159350A - Fuel injection valve device

Info

Publication number: US3159350A
Application number: US93613A
Authority: US
Inventors: Mangold Rudolf
Original assignee: Bendix Corp
Current assignee: Bendix Corp
Priority date: 1961-03-06
Filing date: 1961-03-06
Publication date: 1964-12-01
Anticipated expiration: 1981-12-01

Description

R. MANGOLD FUEL. INJECTION VALVE DEVICE Dec. 1, 1964 Filed Marenga. 1961 2 Sheets-Sheei 1 INVENTOR.

RUDOLF MANGOLD www ATTOR YS Dec. 1, 1964 R. MANGOLD FUEL INJECTION VALVE: DEVICE 2 Sheets-Sheet 2 Filed March 6. 1961 INVENTORv RUDOLF MANGOLB Ml/MQyw/t ATTORN s United States Patent O 3,159,359 FUEL INJECTHN VALVE DEVHCE Rudolf Mangold, Sidney, NX., assigner to The Bendix Corporation, Sidney, NX., a corporation of Delaware Filed Mar. 6, 1961, Ser. No. 93,613 Claims. (Cl. 239-533) This invention relates to a fuel injection valve device. More particularly, in preferred embodiments thereof, the invention relates to a nozzle for the injection of uids such as fluid fuel into the cylinders of internal combustion engines.

The invention has among its objects the provision of an improved simplilied injection device which has a Substantially smaller number of parts and can be manufactured at a marked saving.

A further object of the invention resides in the provision of a device of the character described which is easy to manufacture and which minimizes the necessity for drilling or machining small openings or channels in the device.

Yet another object of the invention lies in the provision of a fuel injection nozzle which may be made of reduced size.

Still a further object of the invention resides in the provision of a fuel injection nozzle wherein dead end channels are eliminated, thereby providing for the more direct flow of fuel to the valve and thence to the orifice of the device.

Another object lies in the provision of a fuel injection nozzle wherein the movable valve element is self-centering, and perfect seating of the valve parts is insured without the necessity of reworking the valve parts or other elements of the device.

The above and further objects and novel features of the invention will more fully appear from the following description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration only, and are not intended as a definition of the limits of the invention.

In the drawings, wherein like reference characters refer to like parts throughout the several views,

FIG. l is a view in vertical axial longitudinal section through a first preferred embodiment of fuel injection nozzle made in accordance with the invention, certain of the parts being shown in elevation;

FIG. 2 is a View in plan of the nozzle of FIG. l;

FIG. 3 is an enlarged view in transverse section through the nozzle of FIGS. l and 2, the section being taken along the line 3-3 of FIG. l;

FIG. 4 is a fragmentary view in vertical axial section through a second embodiment of fuel injection nozzle in accordance with the invention, certain of the parts being shown in elevation;

FIG. 5 is a view in vertical axial longitudinal section through a third embodiment of fuel injection nozzle made in accordance with the invention, certain of the parts being shown in elevation, the nozzle being shortened in length by having a portion thereof broken away; and

FIG. 6 is a view similar to that of FIG. 5, but unshortened in length, of a fourth embodiment of fuel injection nozzle made in accordance with the invention.

In the drawings there are shown four preferred embodiments of fuel injection nozzle made in accordance with the invention. The irst such embodiment, generally designated by the reference character lll, is shown in FlGS. l, 2, and 3; the second embodiment, shown in FIG. 4, is generally designated 10. The first two elnbodiments differ in their upper or outer portions, and so only such portion of the nozzle lll is shown in FIG. 4. The embodiment of FIG. 5 incorporates means for 3,l59,350 Patented Dec. l, 1964 adjusting the initial spring biasing of the valve and means for adjusting the permissible length of travel of the valve which differ from those of the first disclosed embodiments. The embodiment of FIG. 6 incorporates still further different means for adjusting the biasing of the valve and means for adjusting the length of travel of the valve. In the embodiments of FIGS. 5 and 6 the intermediate guiding means 22 for the valve in FIGS. 14, inclusive, is omitted.

The fuel injection nozzle 1t) has an enlongated generally cylindrical body having a forward or inner portion ll of relatively small diameter and an outer or upper head portion 12 of somewhat larger diameter. Outwardly of enlargement 12 the device 10 has a hooded extension 14 within which is housed a valve biasing spring, a means Y for adjusting the biasing of such spring, and means for limiting the opening of the movable valve element, to be described hereinafter.

The device 14B is designed for mounting in an opening 16 in the wall l5 of the cylinder of an internal combustion engine, as indicated in FIG. 1. Nozzle l0, in the installation shown, is retained and sealed in opening 16 by an annular clamping means (not shown) which engages the transverse upper or annular end surface on enlargement 12 and is drawn toward wall l5 of the engine by studs (not shown) threadedly received in passages 17 in such wall.

The

body

11, 12 is provided with an axially extending cylindrical bore 20 within which is disposed an elongated reciprocable valve element or needle. Such needle has an elongated intermediate portion 19 which is of somewhat smaller diameter than bore 20 so as to form a radially thin annular fuel-receiving passage therebetween. Forwardly of portion 19 the needle is provided with a cylindrical coaxial portion 21 of smaller diameter than portion 19. Generally at the location between the junction of portions i9 and 2l the needle is provided with a guide portion 22 which somewhat loosely engages the wall of bore 20. Guide 22 is in the form of a short generally cylindrical enlargement on the needle, such enlargement being divided into four varying quadrants 25 by four equally angularly spaced longitudinally extending grooves 24. In the embodiment shown, grooves 24 extend inwardly to lie tangent to the outer surface of portion 21 of the needle.

Injection nozzle l0 is provided with a separately formed inner or tip portion 26 which is subsequently permanently attached to the main portion of the body of the device. Tip portion 26 of the body has a rearward axially extending pilot portion 27 which is accurately received within the lower end of bore 20. Portion 26 is permanently connected to the lower end of body portion 11 by a brazed joint 33 as shown. Tip portion 26 has an axially extending passage 29 therethrough of somewhat smaller diameter than portion 21 of the needle. The lower or inner end of passage 29 is provided with one or more small orifices 30 through which fuel oil is injected under high pressure into the cylinder of the engine. The lower or inner end portion of member 26 is of reduced diameter and lits within the smaller inner end portion 32 of the passage through the cylinder wall l5. The upper end 34 of body 26 is of the same diameter as body portion lll, thus forming an annular shoulder between

portions

31 and 34. The body of the nozzle is sealed to the engine wall by means of an annular gasket or sealing washer 3d which is interposed between the annular shoulder on portion 25 of the body and the transverse annular surface 35 at the junction between the

portions

16 and 32 of the bore through cylinder wall l5.

The upper end of pilot portion 27 of body 26 is provided with a downwardly converging frustoconical valve seat 40 within which is sealingly received the conical Y ence characters with an added prime.

lower end 39 of the needle portion 21. The upper end of the needle proper is provided with an enlarged circular cylindrical portion 41 which slidably and accurately engages the upperend of bore 20 in the body. To insure the provision of a virtual seal between portion il and `the bore, it is preferred that portion 41 and the upper end portion 42 of the bore be lap-fitted. Liquid fuel under pressure is delivered to the

valve

39, 46 at timed intervals through a radial inlet passage 43 which communicates at its inner end with the annular passage between vthe; needle and the wall of bore Ztl. In the first embodiment, the nozzle is provided with a separately formed inlet fitting 44, the inner end of which is received within a bore 45 in body portion. 12 and is permanently attached thereto by a brazed joint 46. The inlet fitting has a passage 48 which is aligned with passage 43.

The upper or outer end ofthe needle projects outwardly of the main body of the nozzle to a substantial extent.

' Such projection, designated 47, is connected to the needle Yspring 51 which is disposed aboutprojection 47. The upper or outer end of spring 51 tbrustingly cooperates with an elongated cap member 52 secured to the body of the nozzle.

As shown, above enlargement 12 of the body ofthe nozzle there is provided an upstanding hollow boss 55 within which lapped surface 42 of bore 20V is located. The lower end of cap 52 is threadedly secured to boss 55 as shown. Cap 52 has a transverse upper end portion 56 within which are tightly frictionally secured one or more disc-like upper shims 59 and one or ymore annular shims 57. The total thickness of

shirns

57 and 59 may be changed to adjust the initial biasing of spring 51.

y The total thickness of'shims 57 determines the distance Y surface 42, there is inevitably some leakage of fuel upwardly within cap 52 because ofl the high fuel injection pressures employed. To provide for the draining of fuel from the cap, a fuel bleeding port 60 extends radially through the cap as shown. If desired, a suitable fitting may be attached to cap 52 at the location of port 60, the fitting being connected to return the fuel to a sump or fuel tank.

In the first described embodiment, the Valve needle is restrained from radial movement at its outer o r upper end by reason of the engagement between portion 41 of the needle and surface 42 of bore 20. The guide 22 intermediate the lengthl of the needle, however, loosely engages the bore 20 so that the conical valve surface 39 on the inner end of the needle is free to .find its own position in seat 40. Preferably the included angles of the valveproviding inner end of the needle and of the valve seat are slightly different, in order to provide for their sealing engagement at a narrow annulus. A typical satisfactory needle will have an inner end with an included angle of 9030, whereas the mating valve seat will have an included angle of 8930. Thus the nozzle of the invention does not require any extensive reworking in order to insure the formation of a perfect seal between

valve parts

39 and 40. Additionally, it will be seen that the path of the fuel through the device to the valve 39,4r 40 and beyond is substantially direct. Thus there are no dead end pockets or inaccessible channels from which scale from heat treating and burrs or metal chips from manufacturing or other deposits would be diiicult to remove.

The parts of the injection nozzle shown in FIG. 4 which are the same as those in FIGS. 1, 2, and 3 are designated by the same reference characters.- Those parts of the nozzle of FIG. 4 which are generally the same as those of the first described embodiment and have generally the same function are designated by the same refer- In the' injection nozzle of FIG. 4 the fuel inlet fitting 44 is made integral with the portion 12 of the body of the nozzle. A radial passage 43 extends through fitting 44 and into communication with the annular fuel passage between portion 19 of the needle and bore 20 in the body. rThe axially outwardly projecting portion 47 of the needle in FIG. 4 is relatively short, and the lower spring scat 56 has an upwardly projecting sleeve portion telescoped about member 47 and received Within the lower end of spring 51. f

The means for variably biasing spring 51 is, as before, made up of one or more shims. In this instance the shims 57 are annular and are interposed between the upper end of spring 51 and an annular shoulder 67 at the inner end of the thickened outer portion 61 of cap 52.

Readily adjustable abutment means is provided in the nozzle of FIG. 4 for limiting the amount of valve-opening travel of the needle. `Such adjustable abutment means takes the form of a rod-like member 65 which is positioned coaxial of part 47' of the needle and spaced therefrom the distance of the desired needle opening when the valve is closed. Member 65 has an outer larger diametered end portion 64 coaxial therewith, portion 64 being threadedly mounted in a bore 62 at the outer end of cap 52. The axial positioning of abutment member 65 may readily be changed by turning

member

64, 65 as required. For this purpose the outer end of part 64 is slotted at 67 so that it may be turned by a screw driver. A lock nut 66 may be provided on the outer end of member 64 whereby to lock

member

64, 65 in adjusted position.

A third embodiment of fuel injection valve device, generally designated 70, in accordance with the invention, is shown in FIG. 5. Device 70 has a body with an elongated inner or forward end 71 having an axial passage 72 therein. The outer or rear end portion 74 of the body of device 70 has a lateral extension 75 providing a threaded end portion 76 to which a conduit (not shown) containing fuel subjected to pressure pulses may be attached. A laterally extending passage 77 is provided in portion 75 whereby to supply passage 72 with fuel.

The inner end of Ybody portion 71 is generally of conical shape and has a smaller axial passage 79 therein. The inner end of passage 79 has a yet smaller spray orice 80 connecting it to the interior of a cylinder of an engine on which device 7! is mounted. The junction

be-V tween passage

72 and 79 is in the form of an inwardly converging conical seat 81. Within passage 72 there extends an elongated reciprocable valve needle V82 which is of somewhat smaller diameter than passage 72. The forward inner portion of needle S2 is of reduced diameter, suchportion terminating at a conical end 84 which sealingly lits within the conical valve seat 8l. Preferably the included angles of the two valve-forming parts are different, as set forth above in connection with the first described embodiment.V In the device 7d of FIG. 5, as in the device of FIG. 6, to be described, no intermediate guiding means is employed on the valve needle, the valve needle thus being free to flex slightly from its guided portion at the outer or rear end thereof so that surface 84 can lind its own seat in valve seat 8l.

The outer or rear end of the valveneedle is somewhat enlarged at 85 and ts accurately within passage 86 in portion 74 of the body, passage 86 forming a prolongation of passage 72, Passage 86 in its outer end portion extends through an elongated outwardly extending sleeve portion 87 of reduced outer diameter, such sleeve portion being integral with body portion 74. The valve needle is constantly urged toward its inner, valve-closed, position by a coil compression spring, the biasing of which is adjustable. An adjustment of the lengthV of path of retraction of the valve needle is also provided for bythe disclosed structure.

A hollow cap-like member 89 is disposed coaxialiy of the outer end of the valve needle and of sleeve S7 so as4 Y to lie telescopically thereover. The radially inner trans-` verse surface of member 89 abuts the outer end of portion 8S of the valve needle. The forward end of member 89 has a radially outwardly directed ilange portion 90 upon the upper surface of which is disposed one or more annular shims 91. A coil compression spring 92 telescoped about member 89 has the inner end thereof abutting the outer one of shims 91. The outer end of spring 92 abuts one or more disc-like shims 94 which are disposed within a cap member 95 which is sealingly attached to portion 74 of the body by a screw connection 96.

It will be apparent that the biasing effect of spring 92 upon the valve needle is determined by the combined thicknesses of

shims

91 and 94. The permissible length of travel of the valve needle -in a valve-opening direction is determined by the thickness of shims 94. Provision is made for the exhausting of any 'fuel which may leak into the cavity within cap 95. For this purpose a small radial passage 97 extends through the skirt of cap 95, passage 97 being connected to a return conduit (not shown) leading to a sum-p for a fue-l tank.

The fourth disclosed embodiment of fuel injection valve device, shown in FIG. 6, is generally `designated by the reference character 99. The inner or forward portion of such device is generally similar to that shown in FlG. 5, except for the fact that the inner, valve seatproviding portion of the body of the device is initially made as a part separate from the main body thereof, substantially the same as shown in FIG. 1. Consequently, the same reference characters designating the forward or inner parts of the device 99 are employed as in FIG. 5 but with an added prime.

The devices of FIGS. 5 and 6 differ essential-ly by reason of the means employed to bias the valve needle toward the valve-closed position and the means adjustably to limi-t the distance through which the valve needle may be retracted upon the opening of the valve. In device 99 of FIG. 6 the outer end of the valve needle, beyond its guiding portion 85', is extended as a portion 100 of somewhat reduced diameter. Telescoped about portion 100, and resting upon the shoulder 101 located at the junction between

portions

85 and 100 is a 4spring seat device in the form of a washer having a central sleeve and an outwardly directed flange 102 at its inner end. A coil compression spring d, telescoped .about valve needle portion 100, has its inner end restY ing upon flange 102. The outer end of spring 104 is in abutment with the radially inner transverse annular surface of a generally cup-shaped member 105 which has adjustable screw threaded engagement at 106 between its inner end and the outer end portion 107 of the body of device 99. It is thus apparent that the valve-closing force imposed upon the valve needle of device 99 may be adjusted by adjusting the position of member 105 axially with respect to the body of the device. ln order that member 105 may be stably retained in adjusted position, the threads forming the threaded connection 105 may have a tight or interference fit.

Adjustment of the length of retractive movement of the valve needle is provided by a stud 109 which is positioned coaxially of the valve needle and has screw threaded engagement with a central outer sleeve portion 1li) of lmember 105. Preferably a slot 111 is disposed in the outer end of stud 109 to permit its ready adjustment. Stud 109 is held in adjusted position by a lock nut 112 which has screw threaded engagement with the end of the stud projecting beyond member 109, the lock nut abutting rthe outer end of member 105.

The described assembly is housed Within a protective cap 114 which has screw threaded engagement with the outer portion 107 of the body at 115. Preferably as shown a sealing ring 116 is disposed between the outer end of portion 107 and an inner shoulder of cap 114. The removal of fuel which may escape into the spaces within

members

105 and 114 is provided by a radial passage 117 through the skirt of member 105, and by 6 an opening 119 through the cap 114. A suitable conduit (not shown) may be attached to cap 114 at opening 119, so that the fuel within the cap may be returned to a sump or fuel tank.

Although only a limited number of embodiments of the invention have been illustrtaed in the accompanying ydrawings and described in the foregonig speciiication, it is to be especially understood that various chan-ges, such as in the relative dimensions of the parts, materials used, and the like, as well as the suggested manner of use of the apparatus of the invention, may .be made therein without departing from the spirit and scope of the invention as will now be apparent to those skilled in the art.

What is claimed is:

l. A fluid fuel injection device comprising an elon gated main body having forward and rear ends, said body having an elongated passage extending longitudinally therewithin, a forwardly converging frustro-conical valve seat positioned coaxially of the .passage near the forward end thereof, an elongated .cylindrical needle within the passage coaxial thereof, said needle having a conical forward end matingly cooperating with the valve lseat to form a pressure-openable valve, the needle .throughout an extendedjpart of its length rearwardly from and including the forward end thereof having a diameter somewhat less than that of the passage so as to provide a -substantially continuous annular fuel passage between the Wall of the passage and the needle throughout such extended part of the length of the needle, resilient means urging the needle forwardly to seat the valve on said seat, means to support the needle for reciprocation including means to `guide the rear end thereof and to provide a substantial seal against the rearward escape of fuel from the passage, means for introducing fuel under pressure to the annular fuel passage, the needle and the means for supporting and guiding the needle for reciprocation being so constructed and arranged as to give the conical forward end of t-he needle a small freedom of lateral motion whereby it matingly interiits with the valve seat, abutment means cooperating with the rear end of the needle to limit the travel of the needle in a rearward, valve-opening direction, supporting structure affixed to the rear end of the body, said structure supporting the abutment means in .alignment with the rear end of the need-le, said supporting structure and abutment means consisting of a unitary cup-shaped member, the transverse bottom of which forms the abutment means, an inverted cup-like member having its side wall telescoped over the rear end of the needle, the transverse bottom of the cup-like member being interposed between the rear end of the needle and the abutment means, the cup-like member having a spring seat in the form of an outwardly directed annular flange around the side wall thereof, the resilient means urging the needle forwardly to seat the valve being a coil compression spring disposed coaxially of the needle and having its forward end in engagement with the flange on the cup-like member, and a second spring seat on the abutment means retaining the rear end of the spring.

2. The injection device as claimed in claim 1, comprising at least one shim between the outer surface of the transverse bottom of the cup-like member and the abutment means.

3. The injection device as claimed in claim 2, wherein the shim is also disposed between the outer end of the spring and the second spring seat.

4. A high pressure fluid fuel injection device comprising an elongated unitary body member having a bore therethrough, substantially all of said bore being a passage of uniform diameter, a discharge nozzle tip attached to one end of said body member and having a discharge orice and a frustro-conical valve seat coaxial with said passage, an elongated cylindrical needle within the passage coaxial thereof and having a conical inner end matingly cooperating with said Valve seat to form a pressureopenable valve, said needle comprising an e11 larged minor portion at the outer end thereof:` having a close'sliding t in said passage for guiding the needle and substantially sealing the passage and a reduced major portion having a ydiameter appreciably less than the diameter of the passage extending from said enlarged portion to. said conical inner end to form an annular space for the passage of fuel, the lengthof said reduced portion of the needle being several .times greater than the length of said enlarged portion thereof, whereby the conicalA inner end of the needle has freedom of lateral motion to ins-ure accurate seating of said conical inner end on the va-lve seat, port means in the body member between said enlarged portion of the needle and said valve seat for conducting fuel into said annular space around the needle, a unitary hollow cap removably mounted on the other end of said Ibody member, means supported by said needle forming a spring seat, and a lcoil spring in said cap and interposed under compression between 'saidspring seat and said cap. for urging said needle in valve-closing direction,r said last-named means being eng-ageabl'e with said cap for limiting the valveopening movement of Vsaid needle. Y

5. A fuel injection device as defined in claim 4, wherein the nozzle tip isv formed as au integral pant of said body member.

References Cited in the file of-thisy patent UNITED STATES PATENTS 1,289,104 Britton Dec. 3.1, 1918 1,879,912 Armstrong Sept. 27, 1932 1,964,218, Schargorodsky June 26, 1934 2,059,759 Stearns Nov. 3,1936 2,304,404 Flanagan Dec. 8, 1'942 FOREIGN PATENTS 128,898 Ausmiia Aug. 26, 194s 161,145

Switzerland .Tune 16, 1933

Claims

1. A FLUID INJECTION DEVICE COMPRISING AN ELONGATED MAIN BODY HAVING FORWARD AND REAR ENDS, SAID BODY HAVING AN ELONGATED PASSAGE EXTENDING LONGITUDINALLY THEREWITHIN, A FORWARDLY COAXIALLY FRUSTRO-CONICAL VALVE SEAT POSITIONED COAXILLY OF THE PASSAGE NEAR THE FORWARD END THEREOF, AN ELONGATED CYLINDRICAL NEEDLE WITHIN THE PASSAGE COAXIAL THEREOF, SAID NEEDLE HAVING A CONICAL FORWARD END MATINGLY COOPERATING WITH THE VALVE SEAT TO FORM A PRESSURE-OPENABLE VALVE, THE NEEDLE THROUGHOUT AN EXTENDED PART OF ITS LENGTH REAWARDLY FROM THE INCLUDING THE FORWARD END THEREOF HAVING A DIAMETER SOMEWHAT LESS THAN THAT OF THE PASSAGE SO AS TO PROVIDE A SUBSTANTIALLY CONTINUOUS ANNULAR FUEL PASSAGE BETWEEN THE WALL OF THE PASSAGE AND THE NEEDLE THROUGHOUT SUCH EXTENDED PART OF THE LENGTH OF THE NEEDLE, RESILIENT MEANS URGING THE NEEDLE FORWARDLY TO SEAT THE VALVE ON SAID SEAT, MEANS TO SUPPORT THE NEEDLE FOR RECIPROCATION INCLUDING MEANS TO GUIDE THE REAR END THEREOF AND TO PROVIDE A SUBSTANTIAL SEAL AGAINST THE REARWARD ESCAPE OF FUEL FROM THE PASSAGE, MEANS FOR INTRODUCING FUEL UNDER PRESSURE TO THE ANNULAR FUEL PASSAGE, THE NEEDLE AND THE MEANS FOR SUPPORTING AND GUIDING THE NEEDLE FOR RECIPROCATION BEING SO CONSTRUCTED AND ARRANGED AS TO GIVE THE CONICAL FORWARD END OF THE NEEDLE A SMALL FREEDOM OF LATERAL MOTION WHEREBY IT MATINGLY INTERFITS WITH THE VALVE SEAT, ABUTMENT MEANS COOPERATING WITH THE REAR END OF THE NEEDLE TO LIMIT THE TRAVEL OF THE NEEDLE IN A REAWARD, VALVE-OPENING DIRECTION, SUPPORTING STRUCTURE AFFIXED TO THE REAR END OF THE BODY, SAID STRUCTURE SUPPORTING THE ABUTMENT MEANS IN ALIGNMENT WITH THE REAR END OF THE NEEDLE, SAID SUPPORTING STRUCTURE AND ABUTMENT MEANS, CONSISTING OF A UNITARY CUP-SHAPED MEMBER, THE TRANSVERSE BOTTOM OF WHICH FORMS THE ABUTMENT MEANS, AN INVERTED CUP-LIKE MEMBER HAVING ITS SIDE WALL TELESCOPED OVER THE REAR END OF THE NEEDLE, THE TRANSVERSE BOTTOM OF THE CUP-LIKE MEMBER BEING INTERPOSED BETWEEN THE REAR END OF THE NEEDLE AND THE ABUTMENT MEANS, THE CUP-LIKE MEMBER HAVING A SPRING SEAT IN THE FORM OF AN OUTWARDLY DIRECTED ANNULAR FLANGE AROUND THE SIDE WALL THEREOF, THE RESILIENT MEANS URGING THE NEEDLE FORWARDLY TO SEAT THE VALVE BEING A COIL COMPRESSION SPRING DISPOSED COAXIALLY OF THE NEEDLE AND HAVING ITS FORWARD END IN ENGAGEMENT WITH THE FLANGE ON THE CUP-LIKE MEMBER, AND A SECOND SPRING SEAT ON THE ABUTMENT MEANS RETAINING THE REAR END OF THE SPRING.