US1959383A - nowosielski - Google Patents

Description

May 22, 1 934. E, B. NowoslELsKl SPARK PLUG Original Filed Aug. 2, 1929 I N V EN TOR. Edward B. /Vo wo s/'e/sk f' Patented May 2 2, 1934 SPARK PLUG Edward B. Nowosielski, Bloomeld, N. J., asslgnor to Eclipse Machin N. Y.,

e Company, a corporation of New York Elmira Heights,

Original application August 2, 1929, Serial No.

382,985. Divided and 1932, Serial No. 623,848

this application July 21,

8 Claims. (Cl. 1723-489) 'I'his invention relates to ignition systems for internal combustion engines and more particularly to spark plugs. l

l One of the objects of the present invention is to provide an improved spark plug which is both mechanically and electrically strong, and is capable of long service without mechanical or electrical faults.

Another object is to provide an improved spark plug which embodies novel means for preventing the escape of gases from the engine cylinder through the spark plug structure with a consequent loss of compression.

A further object is to provide a spark plug embodying a novel gas-tight seal and an improved shielding means which on account of its simplicity and small number of parts is rugged in structure, cheap to manufacture and easy to assemble.

One embodiment of the present invention is illustrated in -the accompanying drawing, but it is to be expressly understood that said drawing is for the purposeof illustration only and is not to be construed a`s a definition of the limits of the invention, reference being had for this purpose to the appended claims.

In the drawing:

Fig. 1 is a side elevation partly in section of the preferred embodiment of the present invention;

Fig. 2 is a 'sectional view taken transversely of I Fig. 1 on the line 4 4 wherein; and

Fig. 3 is an exploded view of the embodiment shown in Figs. 1 and 2.

Referring now to the drawing, wherein like reference characters indicate like parts throughout the several views, Figs. 1 and 2 illustrate an improved spark plug which embodies novel means for forming a gas-tight seal to prevent the escape of gases through the body of the spark plug from the engine cylinder. In this embodiment, thefplug comprises a body portion 101 which is exteriorly threaded for engagement with the cylinder wall of an internal combustion engine, the upper portion of said body being of increased diameter to provide an inner -shoulder 103. An electrode 104, which is posii y tioned centrally-in the body 101 is providedat its lower end withan enlarged head 105 in which ris secured a spark-gap point 106. The other end of the electrode is threaded at 107 for a purpose to be described hereinafter, and an insulator 108, preferably a mica' sleeve, surrounds the electrode 104 between the head 105 and the threaded 'e'nd" 107. A plurality of insulating washers 109,

preferably of mica, surround the lower portion of the electrode 104 and insulating sleeve 108, adjacent the head 105, said washers preferably being of increasing outer diameter away from Asaid head. 'A substantially cup-shaped electrode 110, the bottom of which is provided with a plurality of perforations 111, through one of which extends the point 106, has its rim bent radially outward at 112 to form a fiange engaging the shoulder 103 formed in the body 101. The electrode 110 is held in said body by suitable means which in the form shown comprises a wedge 113 bearing against the topmost washer 109, and having an inclined surface 114 which is pressed against the flange 112 by means of a gland 115 threaded in the upper enlarged portion of the body 101 and adapted to engage a shoulder 116 formed on said wedge.

The gland 115 is in turn shouldered internally as indicated at 117 to engage the circumferential ange on amember 118 of relatively soft material, the said member having integral tapered portions 120 and 121 extending above and below said flange portion respectively; the lower tapered portion 121 being in cooperative engagement with the inner tapered surface of the wedge member 113, and the upper tapered portion 120 being in cooperative engagement with the inner tapered surface of the gland 115, as shown in Fig. 3.

As best shown in Fig. 3, both the gland 115 and the body 101 are provided with polygonal portions for convenience in assembling, and installations.

A plurality of insulating washers 124 surround the upper portion of the electrode 104 and insulating sleeve 108, and rest on the gland 115, said washers preferably decreasing in diameter toward the threaded end 107v of the electrode, and a terminal member 126 is screwed onto the threaded end thereof. Suitable means are provided for attaching a cable or lead to said terminal member which in the form shown comprises a split spring tip or terminal post 127. The head 105 and the threaded engagement between terminal member 126 and electrode 104 .provide means for tightly clamping together on said electrode the assembly comprising the washers 124, gland 115, wedge 113, and washers Preferably the insulation 109 is assembled Aon the electrode 104 and sleeve 108, then wedge 113 is placed over the electrode. Thereafter member 118 is assembled with the wedge 113, and gland 115 is engaged with the wedge 113 and member 118. As shown in Fig. 3, the upper portion of wedgepll provided with suitable serrations 128 adapted to engage cooperating serrations pro-4 vided on the inner surface of gland 115. 'I-he parts thus assembled are subjected to pressure a suitable press or, in certain instances, the pressure may be applied after insulation 124 has been assembled on the electrode. The pressure is effective through the inclined surfaces of the gland 115 and wedge 113 to force the relatively soft member 118 into intimate contact -with 'the insulating sleeve 108 whereby the latter is wedged into engagement with the center electrode, and a double gas-tight seal is formed arou'nd the electrode. The structure thus assembled is now threaded'into body 101 to engage cup 110 and hold, the latter in operative position within said body. In this assembling process, wedge 113 causes iiange 112 of member 110 to be brought into close engagement with shoulder 103 to form a gas-tight joint at this point. If desired, flange 112 Vmay be doubled upon itself so as to afford an extra thickness of metal at `the point of engagement with shoulder 103 and wedge 113, thereby insuring the gas-tight integrity of the joint.

This constructionrnders it 'unnecessary to employthe usual gasket at this point. The use of the serrations and the pressure applied to the.. parts are eiective to prevent rotation of wedge 113, relative to insulation 109 whereby the seal at this point is preserved. The wedge and gland, after assembly, constitute in eiect an integrally formed member, and retain member 118 in operative position, as well` as the remaining elements.

A lead or cable 125 is connected to the terminal post 127 in any suitable manner, and as shown, is provided withva terminal ring 130 which is adapted to slip over the split terminal 127, said cable being covered by suitable insulation 131,

and as illustrated and claimed in my copending application, Seriali No. 382,985 (of which application the present case is a division) the insulation is in turn covered by a metallic sheathing of woven wire, or other suitable material, the purpose of the metallic sheathingbeing more fully described in the parent application just referred ta There is thus provided an improved sparkplug structure which is rugged and strong rboth mechanically and electrically, and which is compactly and easily assembled from a small number of parts. 4Due to its simplicity, it is also cheap tomanufacture. vided in this spark plug for eiectively preventing the escape of gases from the engine cylinder, through the spark plug structure, and thus decreasing the loss of compression, as well as prolonging the life of the plug.

It will be obvious that the invention is not limited to the speciflcforms describedA and illustrated in the drawing, but is capable of a variety of mechanical embodiments. Various changes, which will now appear to those skilled in the art, may be made in the form, details of construction, and arrangement of parts without departing from the'spirit of the invention. Reference is therefore to be had to the appendedjclaims for a definition ofthelimits of the invention.

What is claimed is: p l. In a spark plug, the combination of a hollow body having a; shoulder therein, an insulated electrode extending throughsaid body, packing means surrounding said insulated electrode and i having oppositely inclined faces, awedge-shaped Imember` supported on said shoulder and v having Novel means are pro.

an inclined face cooperating with one of the inclined faces of said packing means, and a gland f secured in` said body and having an inclined face cooperating with the other inclined face of said packing means.

2. In a y. spark plug, the combination of a' hollow body having a shoulder therein, an insulated electrode extending centrally through said hollow body, a cup-shaped electrode operatively associated with said central electrode and having a iiange engaging said shoulder, a packing sleeve surrounding said insulated electrode, a wedge engaging and holding said iiange on said shoulder and having an inclined face', yand a gland secured" in said body and having an inclined face, said inclined faces engaging said packing sleeve to compress the latter into intimate contact with said central electrode when said wedge and gland are drawn toward each other. l l

3. In a spark plug, the combination of a hollow body, an electrode extending through said body and having a head formed at its lower end,l an insulating vsleeve surrounding said electrodebetween said head and the upper end there* of, a plurality of insulating washers surrounding said electrode and resting against said head, a packing sleeve surrounding said electrode yadjacent said washers, a plurality of insulating washers surrounding the upper portion of said electrode adjacent said sleeve, a wedge supported in said body and engaging one group of washers, a gland secured to said body and engaging the other group Aof washers, said gland and wedge having oppositely inclined surfaces adapted to engage and compress said packing sleeve around said electrode, and a cup-shaped electrode mounted on said body and surrounding said head.

' 4. In a spark plug having a body portion, an assembly adapted to be inserted in said body portion as la unit comprising a 'center electrode having'a head on the lower end thereof, insulation surrounding the electrode above said head, a compressible member surrounding said insulation, and means for forcingy said lcompressible member into engagement with the insulation, said last named means including a wedge provided with serrations and a glandadapted to be forcedA into engagement with the serrated portion of the wedge, said wedge and gland having inclined surfaces for engagement' with the com- '125 pressible member. A

5. In a spark plug, a body having an internally threaded bore, a thimble forming an electrode removably mounted in said body, a wedge member positioned in the bore of the body and in engagement with said thimble, a center electrode operatively -associated with the thimble electrode and extended through said wedge, compressible insulation surrounding a portion of said center electrode, a j plurality of insulating discs interposed between a shoulder on the center electrode and said wedge, a sleeve of compressible material centrally disposedwithin the bore, said /center electrode and compressible insulation passing through said sleeve, a gland threadedv into said Y body and having engagement with the upper porthe upper en'd ofthe center-electrode and having 150 engagement with the upper one of said last mentioned washers.

6. In a spark plug of the type having a center electrode, compressible insulating material surrounding said center electrode, a packing of compressible material surrounding the insulating material, the opposite ends of said packing being of frusto-conical shape with the bases of the conical portions connected by a flange, and means having engagement with said conical surfaces for forcing said packing into engagement with the .insulating material whereby a gas-tight joint is formed around said center electrode.

7. In a spark plug, the combinationrof a center electrode; compressible insulating material surrounding said electrode, a member of compressible material surrounding the insulating material, said member being provided intermediate its ends with a flange and the outer surface of said sleeve tapering inwardly toward the electrode from both sides of said flange, and means for forcing the member against said compressible insulating material.

8. In a spark plug having a body portion, an insulated center electrode, and means for retaining said electrode in operative position in the body comprising a compressible member having engagement with the insulation on the electrode, and inter-engaging serrated members having wedging engagement with the compressible member, one of said serrated members being secured to the body portion.

EDWARD B. NOWOSIELSKI.) f

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