US1307176A - Spagk-plirg - Google Patents

Description

L. R. BENN. SPARK PLUG. APPLICATION man :uwn. 1917.

O "In n L66. 7- Bear;

glwuentoz Patented June 17, 1919.

inarrsn sra rss harass? LEE It. IBENN, OF TAMA, IOWA.

SPARK-PLUG.

To all whom it may concern:

Be it known that I, LEE R. BENN, a citizen of the United States, residing at T ama,

in the county of Tania and State of Iowa,

, electrode and short circuiting the device which will prevent its proper operation. This type of spark plug will tend to keep the adjacent points of the spark gap clean, so as to insure a positive spark during its operation.

The invention has for its primary object to provide an improved electrodeof novel construction, means being also provided to prevent the porcelain core from cracking when the plug becomes hot, and likewise which prevents leakage when the plug is cold.

A further object of the invention is to provide a device of this character which is easily and simply constructed, inexpensive to manufacture, and one which will be very eiiicient in operation.

With the above and other objects in view,

' as will'appear as the description proceeds,

the invention comprises the various novel features of construction and arrangement of parts which will be more fully described herein and set forth with particularity in the claim appended hereto.

"Reference is had to the accompanying drawings forming a part oi this application, in which like reference characters indicate the corresponding parts throughout the several views, in which Figure 1 1s a side elevation of my improved spark plug, partly in section,

Fig. ,2 is a bottom plan view thereof, and

'Fig. 3 is an enlarged detailed sectional viewof the lower end of the main electrode.

"Referring to the drawings in detail, 10

\ designates the porcelain core that is adapted to be positioned in the usual type of casing 11 provided with a wrench engaging surface in the usual manner and having its said lower end externally threaded as shown at 12 so as to permit connection with an engine cylinder.

he casing 11 is provided with I Specification of Letters Patent. Pate t J u 9 V3 191%} Application filed July 11,

1918. Serial No. 244,419.

ranged between the casing and the core as.

is common to spark plugs of this character, said sleeve being inserted into position to form the upper shoulder in the casing, as specified. These gaskets will prevent the core from breaking, when the plug is hot. as Well as to prevent leakage when the plug is cold.

The porcelain plug 10 has positioned centrally therethrough a main electrode 17 which project from the upper end oi the plug as a binding 18 thereon for connecting a lead wire therewith in the usual manner.. The main electrode is of the usual size, wherein it extends through the porcelain plug, and the lower end of the porcelainplug is tapered as shown at 19 so as to correspond with an enlarged lower portion 20 of the main electrode, which projects from the plug and below the lower edge of the casing 11, as shown. This enlargement produces a shoulder 21 between which and the lower end of the porcelain core or plug, an asbestos insulating ring or gasket 22 is positioned, So as to prevent heat from being conducted to the core, thereby preventing heating of the latter, as well as preventing leakage when the plug is cold. The lower end of the main electrode 17 is enlarged as shown at 20, in order to provide strength, in 1 addition to forming a shoulder for the attachment and interposition of the gasket or insulator, as described. Formed atthe lower end of the electrode and the enlargement 20, is an inverted conical head-like portion 22, the sariie being provided with diametrically opposite notches 23, the walls of which bevel in opposite directions, while the opposed sides of said enlargement are beveled at right angles to the bevels of the walls of the notches 23, as shown at 24, there being; a shoulder 25 formed between the enlarge- 1 nent20 and the inverted conical enlargement 22 for a purpose to be hereinafter more fully set forth, v

Ell

Depending from the lower edge or end of the casing- 11 is a. branch electrode 26, whichis angular and has one end portion connected to the lower edge by securing blocks 27, while the free end thereof extends inwardly toward the enlarged head of the main electrode and is spaced therefrom to form. the spar: gap.

It should be noted that the notched por tion is contiguous with and of the same size as the enlargement 20 and by providing the enlarged head 22, producing. a shoulder as specified, the firing surface willhe protected from oil and like collection of foreign matter, thc'surfaces draining by reason of the construction described.

Also owing to the fact that head of the main electrode is the notches and beveled surfaces on its extremity no continuous surface will he presented that would permit carbon deposits forming thereon. The main electrode is so arranged that one of the hcvelcd faces is disposed adjacent the ends of the branch electrode so that a perfect spark is insured. This will present a flat surface adjacent the end of the branch electrode so that there the enlarged provided with will he no likelihood of the spark plug missmg while in operation. The notches serve to break the continuous lower edge oi the extremity, and consequently will prevent carbon deposits forming thereon to short circuit the plug. The beveled faces, owing to their inclination, tend to throw the explosive charge downwardly and prevent any u-ndue backing of gases within the chamber formed between the lower end of the core and the casing, this also being assisted by the lower tapered formation of the plug or core, as specified. Likewise, the provision of the gasket or insulating rings obviates the breaksulated core terminating short of ecture ing of a plug when the latter becomeshot, as well is cold.

From the foregoing description taken in connection with the accompanying drawings, it is thong it that a clear and comprehensive understanding of the construction,

operation, and advantages of my inventionmay be had and while I have shown and and scope of the invention as claimed.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

A. spark plug comprising a casing, airinthe lower edge thereof, a central electrode extending through said core and projecting from the bottom of the same below the edge of the casing, the projecting portion of said electrode being enlarged to provide a shoulder adjacent to said core, an insulator between said enlargement of the central electrode and the core, said core being tapered adjacent thereto, and the lower end of the en larp'cnicnt of the main electrode having an inverted cone'shapcd enlargement provided with opposed beveled surfaces and a groove therein with opposedl" beveled notches conforming to the enlargement and disposed at right angles to the beveled facesiirst- IHGIL tioned, and a branch electrode projecting from the lower edge of the casing to a point adjacent the! extremity of the main electrode.

In testimony whereof, I aliixiny signa-- ture hereto.

LEE B. BENN.

as to prevent leakage when the plug

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