US1247345A

US1247345A - Spark-plug.

Info

Publication number: US1247345A
Application number: US16921017A
Authority: US
Inventors: Myles Standish
Original assignee: Individual
Current assignee: Individual
Priority date: 1917-05-17
Filing date: 1917-05-17
Publication date: 1917-11-20
Anticipated expiration: 1934-11-20

Description

M. STANDlSH. SPARK PLUG. APPLICATION FILED MAY 17. 1911.

Patented Nov. 20, 1917.

UNITED STATES PATENT OFFICE.

MYLES STANDISH, F OMAHA, NEBRASKA.

SPARK-PLUG.

' Application filed May 17,

To all whom .z't may concern:

Be it known that I, MYLES citizen of the United States, residing at Omaha, in the county of Douglas and State of Nebraska, have invented certain new and useful Improvements in Spark-Plugs, of which the following is a specification.

This invention relates to an improvement in spark plugs, and has for one of its objec'ts to provide such a construction that the inner end of the central, insulated electrode will be prevented from becoming unduly heated, to thereby avoid preignition of the gas charges. Another object is to pro- STANDISH, a

vide a metallic part or washer on the central electrode adapted to conduct heat and to cause heat to be communicated from the electrode to a conoidal face formed at the end of the stem of the insulating core, to cause combustion of soot and thereby avoid short circuits at the exposed end of the stem. Another object is to provide an insulating jacket within the stem of the insulating core, for the central electrode, so that the spark plug will continue to be operative in instances when the stem becomes fractured or broken.

The invention also has reference to the formation of a recess disposed in the plane of the conoidal face of the stem and opening on the end of said stem for containing a gasket and washer, and to the use of a sleeve for protecting one of the metals employed against the action of heat, said sleeve providing a support when the central electrode is pressed outwardly of the insulating core for bracing and preventing vibration of said electrode and for compressing the gasket.

With the.foregoing objects in view and others to be mentioned hereinafter, the invention presents a novel construction, combination and arrangement of parts as described herein and claimed, and as illustrated in the accompanying drawing, wherea Figure 1 is a the spark plug.

view in side elevation of Fig. 2 is a view of the same in longitudinal section. Fig. 3 is an enlarged detail relating to Fig. 2.

Referring now to the drawing for a more particular description, the invention is illustrated in connection with a longitudinally apertured insulating core 4, a tubular, metallic housing or ground electrode of con- Speciflcation of Letters Patent.

Patented Nov. 20, 1917.

1917. Serial No. 169,210.

ventional form for a spark plug, being in dicated at 5.

On account of the high degree of speed at which motor vehicles are often driven, the central, insulated electrodes, usually constructed of steel, attain a degree of heat sufficient to cause ignition of the gas charges before the gas has become compressed, and known as preignition.

In order that this objectionable feature may be avoided, I provide for the insulated electrode a central, electrical conductor 6, preferably constructed of steel, and a tube 7 of copper or similar metal having a degree of heat conductivity greater than steel.

It will be appreciated that the use of steel will provide rigidity for this electrode and that steel will prevent warping. The copper, on account of its heat conductivity, will readily conduct the heat from the inner end of the electrode and cause it to be communicated to the insulating core, and thence to the atmosphere to prevent pre-ignition of the gas charges. The proportion of steel and copper for the electrodes may be changed, as may be required to correspond with difierent kinds of motors. In instances where the inner end of the electrode is subjected to a degree of heat greater than ordinary, the tube of copper may have a greater thickness, and preferably the tube has a length substantially equal to the length of the central steel conductor.

On account of vibration and stresses directed thereto, the stem at of the insulating core occasionally becomes broken and separated from the body of the core, or becomes fractured, to render the spark plug inoperative, from short circuits. In order that these objectionable results may be avoided, the stem is provided with an insulating jacket 8, preferably constructed of mica, which circumscribes the copper tube; and on account of this construction, the stem, if broken or fractured, will not become displaced or separated from the body of the insulating core, and the jacket 8 will prevent short circuits, in the instances mentioned.

Numeral 9 indicates a depression or recess disposed at the longitudinal axis and opening on the end of the stem a. said recess be ing circumscribed by a conoidal face 10, at said terminal. The recess is adapted to contain a gasket 11 and a metallic ring or washer 12, the latter operating as a heat-conducting element. It will be noted that the recess has a depth sufiicient, only, to contain these two elements, this being a desirable feature so that the washer, when the parts are assembled, may be disposed substantially flush with the end of the stem, no depression being formed for a deposit of carbon therein, and also that said washer will be disposed in close proximity to the inclined face At 13 is indicated a sleeve provided with a projection 14 at its outer end, said sleeve and its projection being constructed of nonincincrating metal and providing a support for member 12 when, by use of the screwcap 15, pressure is applied to the gasket 11,

the projection l-'l preferably bein secured to the central steel conductor. use of this construction, if the stem :2 is ractured or broken, it will be pressed in a direction of the body of the insulating core, since the sleeve 13 and parts within the recess provide a support for this purpose.

uring operation, member 12 will become intensely heated since it is in engagement with the copper tube, and this heat, on account of the attenuated terminal, will be conducted to the conoidal face 10 of the stem, with the result that thereon will be effected, and short circuits avoided. Member 12, preferably, is not threaded on the tube, and this feature facilitates assemblage of parts.

lVhile steel and copper have been specifically mentioned as the two metals used for the insulated electrode, it will be understood that other metals may be substituted, one to provide rigidity and to prevent. warping, and the other to be, comparatively, a more ready conductor of heat, and to be protected from the ignited gases by member 13 or its equivalent.

I claim:

1. The herein improvement in spark plugs, comprising, in combination with an insulating core having its inner terminal provided with a conoidal face, an electrode traversing and projecting beyond the inner end of the core, and consisting of a central. conductor, a tube circumscribing the central conductor, a coat of mica circumscribing the tube, said tube having a greater degree of heat conductivity than the central conductor, a metallic heat conducting element on the tube adjacent to said conoidal face, and a metallic non-calcinating sleeve provided with a pro jection and circumscribing that part of the tube which projects beyond the inner end of the insulating core.

In a spark plug the combination of an insulating core provided at its inner terminal with an annular recess and a conoidal face outwardly of said recess, an electrode trav- 10 for conducting heat thereto. 7

ersing and projecting beyond the core, and consisting of a central conductor, a tube cir cumscribing and having a greater degree of heat-conductivity than the central conductor, an insulating coat in the insulating core and circumscribing a part of the tube, a heat conducting element engaging the tube and disposed in said recess, and a metallic noncalcinating sleeve provided with a projection and circumscribing that part of the tube outwardly of the insulating core.

3. In a spark plug, the combination of an insulating core provided at its inner terminal with a recess and formed outwardly in the plane of said recess with a conoidal face, an electrode traversing and extending beyond the core and including, a central electrical conductor, a tube circumscribing and having a greater degree of heat-conductivity than said conductor, packing in said recess abutting upon the insulating core, a heat coir ucting ring on the tube abutting upon the packing with its outer side disposed substantially flush with the end of the insulating core, and a metallic, non-incinerating sleeve provided with a projection and circumscribing that part of the tube outwardly of the insulating core.

4. In a spa-r: plug, an electrode, an insulating core within the electrode, said core having a stem provided with a recess openmg on its end and having a conoidal face encircling the recess, a second electrode traversing the recess and insulating 'core and provided with a projection, a gasket in said recess, a metallic ring disposed on the sec ond electrode in the plane of the conoidal face of said stem, a sleeve between the projection of the second electrode and the metallic ring, and means to press the sleeve against the metallic ring for compressing the gasket.

5. In a spark plug, an electrode, an insulating core within the electrode, said core having a stem provided with a recess opening on its end and having a conoidal face encircling the recess, a second electrode traversing and having an extension outwardly of the end of the insulating core, said second electrode including a steel conductor and a copper tube circumscribing said conductor, a screw cap mounted on the second electrode, a gasket in said recess, a metallic ring disposed on the copper tube in the plane of the conoidal face of said stem, a sleeve outwardly of the end of the insulating core on the extension of the tube to abut upon the metallic ring for pressing the gasket against a wall of the recess and for disposing said ring substantially flush with the end of the stem of the insulating core when the screw cap is actuated.

In a spark plug, an electrode, an insulating core within the electrode, said core having a stem provided with a recess opening on its end, a second electrode traversing the recess and insulating core and having an extension disposed outwardly of the end of the stem, said second electrode including a steel conductor and a copper tube circumscribing the steel conductor, a gasket in said recess, a metallic ring on the copper tube, a sleeve on the extension of the second electrode, said screw cap being revoluble for disposing said ring substantially flush with the end of the sleeve of the insulating core in engagement with the gasket.

7. In a spark plug, an electrode, an insulating core within the electrode, said core having a stem provided with a recess opening on its end and having a conoidal face encircling the recess, a second electrode traversing and having an extension outwardly of the end of the insulating core, said second electrode consisting of a steel conductor, a copper tube circumscribing said conductor and an insulating coat in the stem encircling the tube, a

of the insulating core screw cap mounted on the second electrode,

a metallic ring disa gasket in said recess,

posed on the copper tube in the plane of the conoidal face of said stem, wardly of the end of the insulating core on the extension of the tube to abut upon the metallic ring for pressing the gasket against a wall of the recess and disposing said ring substantially flush with the end of the stern of the insulating core when the screw cap is actuated.

8. In a spark plug, an electrode, an insulating core within the electrode, said core having a stem provided with a recess opening on its end a second electrode traversing the recess an. insulating core and having an extension disposed outwardly of the end of the stem, said second electrode consisting of a steel conductor, a copper tube circumscribing the steel conductor and an insulating jacket in the stem circumscribing the tube, a gasket in said recess, a metallic ring on the copper tube, a sleeve on the extension of the second electrode, said screw cap a sleeve outbeing revoluble for disposing said ring substantially flush with the end of the sleeve of the insulating core inengagement with the gasket.

9. In a spark plug the combination of an insulating core having a stem provided at its inner terminal with an annular recess, an electrode traversing and projecting beyond the stem of the core, and consisting of a central conductor, a tube circumscribing and having a greater degree of heat-conductivity than the central conductor, an insulating acket in the stem of the insulating core and circumscribing the tube, a asket 1n the recess, a washer on the tube an disposed in said recess, and a metallic non-calcinating sleeve provided with a projection and circumscribing that part of the tube outwardly of the sleeve of the insulating core.

10. In a spark plug, an electrode, an insulating core within the electrode provided with a stem, a second electrode traversing the insulating core and having an extension disposed outwardly of the end of the stem,

said second electrode consisting of a steel conductor and a copper tube circumscribing the steel conductor, an insulating aeket 1n the stem circumscribing the tube, and a nonincinerating sleeve circumscribing the extension of the second electrode.

11. In a spark plug, an electrode, an insulating core within the electrode provided with 'a stem, a second electrode traversing the insulating core and having an extension disposed outwardly of the end of the stem, said second electrode consisting of a steel conductor and a copper tube circumscribing the steel conductor, and a non-incinerating sleeve circumscribing the extension of the second electrode.

In testimony whereof, I have afiixed my signature in presence of two w1tnesses.

. MYLES STANDISH.

Witnesses:

HIRAM A. S'rrmsns, ARTHUR H. Srrmons.