US1258180A - Spark-plug. - Google Patents

Description

n. BREHMEYER.

' SPARK PLUG.

APPLICATION FILED AUGJS. "16.

1,258,186, mm Mai. 5. i91&

der.

UNITED STATES PATENT OFFICE."

KERRY BBEHMEYEK, 0F PRINCETON, NEW JERSEY.

To all whom it may concern: I

'Be it known that I, HENRY Bnnnunrna, a citizen-of the United-States, residing at Princeton, countyof Mercer, and State of New Jersey, have invented certain new and useful Improvements in Spark-Plugs, of

which the followin is a specification.

This invention re ates to improvements in spark plugs, andhas for its general object to provide a construction which will render those arts of the lug which are exposed direct y to the action of the gases in exploding, easilyaccessible when occasion rc--- 'quires that the said parts be inspected or cleaned. And a further object is to provide means for preventing short circniting through the plug. And to these ends the invention resides in adapting the insulator and the casing therefor to cooperate so as to leave exposed a generous portion of the inner end of the insulator, in providing a scraper for the ex osed inner end portion 'of the insulator an in adapting such scraper to be 0 rated by the explosion of the gases when t ese are ignited in the firing chamber.-

Other objects will appear and be better 'understood from that embodiment of my invention of which the following is a speci fication, reference being had to the accom panying drawings forming part hereof and Figure 1, is a detail showing the casing in vertical lo itudinal section and the insulator partly 1n section and partly in side elevation. g

Fig, 2, is a detail sectional plan tesen through the exposed inner end portion of the insulator and-showing the scraper.

a Inthe'drawingsW indicates the plug,

5 of which-is formed of metal 4 the casing and-has what will'be subsequently termed its inner end portion 6 screw threaded, and its outer end portion somewhat enlar ed and polygonal in-contour as indicated by The screw threaded portion 6, screws into the usual o ning in the wall of an engine cylnr I der an the polygonal outer end portion 7 gerovides a surface onto which a wrench may readily adjusted in the actjof attaching the plu to or'detaching it from the cylin ,The bore ,8 of the sleeve extends from the. inner end thereof to approximately the middle oounterred portion 9. The presence of th' counter-bored portion 9 provides an 1nahoulder 1Q,at' the middleportion of SPABKrPLUG.

Specification 01 Letters Patent.

in the insulator andrgr e inner end portion 23 ortion where it terminates in athe sleeve. The insulator 11 extends through Patented Mar. 5, 1918. Application filed August 10, me, Serial mi. 115,113.

the sleeve and between its ends the said insulator has a c lindrical enlargement 12.

which correspon in diameter approximately to that of the counter-bored portion 9, m which it is disposed and arranged between the shoulder 10 and the lock nut 13 which is screwed in o the countenbored portion 9. Gaskets 1 are interposed between the adjacent surfaces of the enlargement 12 v the lock nut 13 and the shoulder 10, an

the lock nut is adjusted so as to coiiperate sponds approximately in diameter to the Thus it will be seen that the bore thereof. portion 16 is sufficiently thick togive the stability reguired of an insulator in a device of this kin The insulator 11 has a longi-, tudinal bore 17 in which is dis the electrode 18. The outer end portion of the electrode 18 extends beyond the correspond ing end ortion of the insulator and is screw threaded as indicated at 19. A binding nut 20 is-screwed onto the ates to secure the terminal of the electrical portion 19 and operconductor or wire to the projecting end portion of the electrode 18.

The inner end of the electrode 18 is pro vided with a substantially spherical aha head 21'whichis disposed in coo; tarbored inner end portion 22' of the insulator.

And the said counter-bored portion 22 18 l0 lproportioned with respect to the size of the end that the same 15 practically housed within the counter-bore.

With this construction it is obvious that the electrode pre scnts but a minimum of surface to be operated upon when it is found necessa to remove soot or carbon therefrom. T e head 21 moreover is adapted to coii crate with the binding nut 20 to tighten t e electrode event leakage through the bore thereof. of the insulator is relatively thin as compared with the outer end portion 16 and fits nicelywithin the bore 8' of the casin 5. A considerable length of the inner en portion 23 is ex osed and extends beyond the inner end 0 thecasin 5. This con- 'struction permits of inspecting orcleaning of the inner when occasion requires and without requiring removal from the casing that portion of the insulator which is exposedvto the flame of the gases in exploding. A finger or electrode 2'; is secured to the inner end of cas- 5 and has its free end portion bent or 0 erwise suitably disposed so as to co'o'perate with the head 21 of the electrode 20 to provide an intervening space which constitutes the usual spark gap. 7

It will now be noted that by reason of the Ian h of the inner ortion 23 and the ex ose extension there-o the said s ark gap wi 1; when the In is connected to e usual t pe of cylin er e disposed well within the explosion chamber with the resultthat when the mass of explosive mixture is comressed in the firing chamber the s ark will 1 ite such mass at the centre portion t ereof.

Manifestly the exposed extension of the inner portion 23 of the insulator and the finger or electrode 24 will present surfaces onto which carbon will readily deposit.- T-herefore and in order to prevent a rapid accumulation of carbon on these parts a scra or 25 in the form of a ring arranged on t e ex osed extension of the inner portion 23 o the insulator'and a recess 26 is formed in the scraper which receives the finger or electrode 24; The scraper is made relativel narrow so that it Wlll have an a precia le amount ofsliding movement on t e ex' osed extension on the inner portion 23 an on the finger or electrode 24,ja nd a stop 27 arranged 1n a groove 28 near the end ortion 3 is rovided for preventing disp aceme'nt of t e scraper from the insulator. When the spark'plug is con: nected to a cylinder and arranged in an upri ht position the scraper 25 issupported' by t e stop 2:? so that when a charge of combustible mixture s exploded at a point below the scraper, the ex los'ion will cause the scraperto ascend un it strikes against the inner end of casing 5; After the explosioi of the mixture the scra or will descend until itstrikes the stop. 2 Thus it will August 1916'.

be seen that the semi er reciprocates on the insulator and electr e 24 an by this action operates to prevent the relative] ra id formation of a film or coating 0 car on tween the electrodes and the casing 5 with, the result that short circuiting ofi the. current through the plug will be prevented. It is obvious that the scraper 25 niay be modified sodas not to'en age electrode 24 and thereby operate on e exposed extension only. I What is claimed as new is:

as I

1. In a spark plug the combination of a" .casing, an insulator disposed therein and having one end portion exposed and extendcasing and extending beyond the end thereof, said insulator being provided with a longitudinal bore the inner end. of which terminates in'a-counter-bore and further having an intermediately disposed enlargement arranged in the counter-bored portion of the casing and supported b the shoulder, an electrode arran d in e bore of the insulator and having in its inner and ahead disposed in the counterbore ,ofthe insulator,

a second electrode connected to the casing and used in operative relation to the head 0 the first namedelectrode, a lock nut surrounding the insulator and disposed in the casing and a scraper alidingly mounted on the extending inner end portion of tll gdinsulator and on the second named elect e. V

In testimony whereof, I have name to thisspecification', this sign ed du g nmisr BREBMEYEI'I. I

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