US1695632A

US1695632A - Spark plug

Info

Publication number: US1695632A
Application number: US173720A
Authority: US
Inventors: Charles C Campbell
Original assignee: Individual
Current assignee: Individual
Priority date: 1927-03-08
Filing date: 1927-03-08
Publication date: 1928-12-18
Anticipated expiration: 1945-12-18

Description

Dec" 18, 1928.

2 INVENTOR.

CharYes 'C. Campbell Patented Dec. 18, 1928.

UNITED mas lemme c. onnrrnnnnor wnsnmcron, "DISTRICT or cononnrn;

-SPABK PLUG.

nppumnminnd mama-1. sesame-1123320, 1 1

-Thisinvention 1min {ringsideslgned. primarily vfor, use in eonnection .1 with that type of internal eomhustion engines or motors provided .withrsookets ionithe reception of the spark plugs and miththese latter set in with respect totheoutenfaceof; the

engine.hlock, forexampleienginesor motors of the Knight type andzthe invention has for its object to,providqinatmanner as hereinafter ,set forth,- a spark iphugrsm'finm' structed and so arranged with; respectt th engine block. to overcome sparkin .onshort circuiting at the outer end of the ug under such conditions providing .for any 'eficient operation of .the, engine onmotor.

1n the motors of ithe typeehaving the spark lugs set: in withirespeet tothe outer face 0% the engine it'zirequently happens that short circuiting is .hadat'the outer end of theiplug, due .to the nearnessofthe engine block,which prevents the plugs firing inthe combustion chamber, andsto oyencome such objectionand .toiinoreaseuthe efliciency of the engine is the aimioianspark plug, in

accordance with thisuinvention and to this end the invention resldesiinnrxapgingmhe outer terminals of the plugs the desiredidls" tancefrornthe outer: face ofthe a 'ne block toIprevent spanking atstheiouterib of the plugs, under such imoditions "owercQmi-ng short circuiting with respect i to the, plugs.

Further iobjectszaof the inveatipn are to 1 provide, in a manner as-here'wafter set forth, a spark plug for the ,purposeereiermdto which is simple initsiconstructiomand.an.

rangement, strong, admirable, thoroughly eflicient in itsuse,neadily 1nstalled,and 1116K- pensive to manufacture.

With the foregoing and other. iobiects in s.

,end of the core 8 andalso from the inner end view the invention consists. obanovelconthat changes, variations and imodificatipns can be resorted to which fall withinnthe p g inner section 11 and an outer section 12,

scope of the claimshereunto appended. i

In the drawings wherein "like reference,

n nlarged scale, ofaspark plug'in accordance with this invention.

Figure 3 is a section on line i=4 Figure 2. iFlgure 4 is a fragmentary view, in vertical section, ofa modified form of plug. Referring to ,tlie drawings in detail 1 generally indicates a metallic shelliformed ofran outeraportioni 2 and anninner portion The outer, portion 2 is of ,igreatervouter and inner diameters than the portion 3, whereby the latter is inset with respect to said outer portion 2. The inner portion 3 is provided. with threads 4 for connecting the shell 1 to the engine .blockto securethe plugnin position. The inner face, of :the outer .portion2 is threaded, asat .5. The outer part of said portion 2 is enlargedand of polygonal contourns at,6, to facilitate the securing and removingfthe shelllgto and from the engine block. :Formed integral, with the inner, end edge oftheshell 1,,is the outer electrode i 7 l which is of .angleshaped con-tour sol astoextend towards the axis of the shell 1. i

.. j indersbetweenethe outer part 2 and inner part 3 of theshelljl. Thecore8 is fixedly.

, secured toqthesshell; lyby a -speripherally threaded flangedcollanor sleeve 9 which: engages with the thncadsoofthe shell 1. and has its inner, end-edge .bearagainst the core ,8 wherebythe latter is fixedlyclamped to ,the shell 1.

Extending axially through the core 8, as

well as fixedly secured therwith is a central electrode 10 which projects from the inner ofjthe shcllland coacts with the outer electrode 7. The central electrode 10 is of a lengthtoproject a substantial distance from the engineblockto prevent sparkingahthe outer end of the plug to, overcome short, circuiting.

The central electrode 10 is formed of, an"

which is of greater diameter than the section 11. ,Theseotion 12 at its inner {end is formed :with a lengthwise extending socket; 13 having a threadednvall with which engages the threaded outerterminal portion 14 of the section 11. The section 12 between its transverse median and its outer end is formed with an annular flange 15, and that part of the section 12 exteriorly of the flan e 15 is threaded as at 16 for engagement liy an interiorly threaded cap member 17 to clamp a circuit wire connection, not shown, to the flange 15, whereby the central electrode 10 is electrically connected with a source of energy. The cap member 17 preferably is constructed of insulation material.

The core 8 centrally thereof, is formed with an elongated socket 18 and a mortise 19 at the outer end of the socket 18. The socket 18 extends below the transverse median of the core. Seated throughout the socket 18 and extending from the core 8 to the section 12 ot the central electrode 10, is a sleeve 20 of insulation material which closely envelopes the section 11 from the inner end of the socket 18 to the inner end of the section 12. The mortise 19 is formed in the outer end of the core 8, seated in said mortise and extending from the core 8 to the flange 15 is a sleeve 21 of insulation and which snugly embraces the sleeve 20 and also a part of the section 12 01 the electrode 10. The periphcry of the sleeve 21 is flush with the edge of the flange 15 and the latter binds against the sleeve to fixedly secure it in position. The section 12 of the electrode 10 oinds against the sleeve 20 to secure it in position and the periphery of the sleeve 20 is flush with the periphery of that part of the section 12 in which is formed the socket 13.

he modified form shown in Figure 4, is the same as that illustrated in Figure 2, with this exception that the outer sleeve of insulation, indicated at 22 is mounted directly upon the outer end of the core 8 and does not extend into a mortise, as the core indicated at 23 is not provided with a mortise for the reception of the inner end of the sleeve Otherwise than that as stated the construction shown in Figure at is the same as that referred to in connection with Figure 2.

The central electrode 10 is of materially greater length than the depth of the socket formed in the engine head in which the plug to be mounted and of such length with respect to the depth of the socket as to project a substantial distance from the mouth of the latter to prevent a sparkin action at the outer terminal of the plug with respect to the outer taco of the engine head, under such conditions overcoming short circuiting, with respect to the plug, resulting in increased engine efficiency, therefore it is thoughtthe many advantages of a spark plug, in accordance with this invention, can be readily understood, and although the preterred embodiment of the invention is as illustratet, and described, yet it is to be understood that changes in the details of construction an be had which will fall within the scope of the invention as claimed.

\Vhat I claim is:

1. A spark plug comprising a metallic shell provided with an outer electrode, a core of insulation secured in the shell, a central electrode extending through the said core and projecting from the outer end thereof and formed with a flange adjacent to its outer end, a air of concentrically arranged sleeves of msulation interposed between the flange and the core, the inner ot the said sleeves having its inner end extended from the inner end of the outer sleeve and the outer end of the outer sleeve extending from the outer end of the inner sleeve.

2. A spark plug comprising a metallic shell provided with an outer electrode. a core of insulation secured in the shell, a central electrode extending through the said core and projecting from the outer end thereof and formed with a flange adjacent to its outer end, apair of concentrically arranged sleeves of insulation interposed between the flange and the core, the inner of the said sleeves having its inner end extended from the inner end of the outer sleeve and the outer end of the outer sleeve extending from the outer end of the inner sleeve, said central electrode formed of an inner and outer section connected together, said inner sleeve having its outer end abutting against the inner end of said outer sec tion, and the said outer section extending from said outer sleeve and having its flange abutting against the outer end of the outer sleeve.

3. A spark plug comprising a metallic shell provided with an outer electrode, a core of insulation secured in the shell, a rentral electrode extending through the said core and projecting from the outer end thereof and formedwith a flange adjacent to its outer end, a pair of concentrically arranged sleeves of insulation interposed between the flange and the core, the inner oi the said sleeves having its inner end extended from the inner end of the outer sleeve and the outer end of the outer sleeve extending from the outer end oi the inner sleeve, said central electrode formed of an inner and outer section connected together, said inner sleeve having its outer end abutting against the inner end of said outer section, and the said outer section extending from said outer sleeve and having its flange abutting against the outer end of the outer slceve, and said sleeves having their inner ends seated within the core.

In testimony whereof, I ailix my signature hereto. 7

CHARLES C. CAMPBELL.