US962314A - Jump-spark igniter-plug. - Google Patents

Description

L. B. CHERRY.

JUMP SPARK IGNITER PLUG.

APPLICATION FILED JAN. 17, 1910.

Patented June 21, 1910.

z .0 a I 1 1 1 1 r .u. I

WWW

ments in spark ears are grn rnnc LOUIS BOND CHERRY, OF ABERDEEN, SOUTH DAKOTA, ASSIGNCR, BY DIRECT AND MESNE ASSIGNMENTS, TO THE BALL MULTI-SPARK PLUG- 00., OF ABERDEEN, SOUTH JUMP-SIP acacia.

Application filed January 17, 1910. Serial No. 538,525.

Specification of Letters .iatent.

DAKOTA, A coarona'rron or sonrn nexora.

:1 IGNITER-PLUG; I

Patented June 21, 1910.

will enable others skilled in the art to which it appertains to make and use the same.

ThIS invention relates to certain improvelugs for internal combustion engines, and more particularly to improvements in what might be termed jump spark igniter plugs; and the objects and nature of the invention will be readily understood by those skilled in the art in the light of the following explanation of the accompanying drawings illustrating what I now consi er my preferred embodiment from among other formations, arrangements and combinations within the spirit and scope of my invention.

An object of the invention is to provide certain improvements in spark plugs whereb liability of fouling and short circuiting wifl be reduced to the minimum, and an exceedingly eflicient, simple and durable device wi 1 be produced for the urposes intended. A further object of e invention is to provide certain, simple, durable and efiicient improvements 1n spark plugs for the purose of intensifying and'increasing the caoric value of the spark produced.

The invention consists in certain novel features in construction, in formations of parts, or in combinations and arrangements as more fully and particularly set forth hereinafter.

Referring to the accompanying drawings:

Figure 1, 1s a side elevation of a plug, on

plosive en 'ne as will be readily understood y those s illed in the art. This shell at its outer end is exteriorly formed at 10, to receive a wrench or other implement whereby the plug can '56 rotated in screwing the same into or from the cylinder. The outer portion of the'internal longitudinal bore of the shell is enlarged and threaded thereby formin the intermediate annular outwardly facing internal shoulder 11, from which the reduced )ortion of the bore extends to the inner en of the shell.- At its inner end, the shell is preferably formed with an internal an iular flange or bead 12, around the inner end opening of the shell. This'fiange or bead is preferably rounded or semi-cylindrical in cross section and preferably is formed with a continuous smooth surface unbroken by points or projections throughout the circle thereof, to form and constitute a rounded continuous or annulamelec- 'trode projecting inwardly beyond the internal surface of the shell bore.

2, is the longitudinal elongated insulating plug or body composed of any suitable insulating or non-conductin material, .such as porcelain or the like, an formed to longitudinally and removably enter the bore of the shell and to be held thereinby the nut 3, through which the insulating plug or body looselyextends, and which screws into the threaded outer end of the shell bore and forces the insulating plug inwardly of the shell by the engagement of the inner end of the nut with the annular shoulder shoulder 11, and surrounding'the reduced inner end portion or skirt 21 of the insulating plug and seated against the usually flared or inclined annular exterior shoulder 22, of said plug. If so desired, this packing ring can be formed by one or more asbestos washers covered by or inclosed wlthin a rin of copper or other suitable sheet material? The outer end of the plug adjusting and clampin nut 3, beyond the outer end of the shell, is formed with an exposed enlarged head 30, formed to receive a wrench or other instrument whereby the nut can be rotated to screw the nut inwardly or outwardly within the shell. The reduced inner end portion of the insulating plug forms an annular skirt 21, arranged on 'tudinally and concentrically within the re uced portion of the bore of the shell and terminating short of the annular end electrode 12, of the shell, and, forming an annular fluid compression chamber within the shell around said skirt and extending from the open inner end of the shell longitudinally thereof to the packing washer 4. The insulating plug is formed with a longitudinal bore extending through the length thereof, and the inner end portion of this bore is enlarged to form a compressed fluid cavity or chamber 24:, open at the inner end of the plug and forming the hollow interior of the skirt 21, and terminating in the intermediate internal annular seat or shoulder 23, within the plug.

5, is a longitudinally threaded conducting stem or rod removably extending through the bore of the insulating plug an projecting beyond the ends thereof, and at its inner projecting end carrying the electrode 50, fixed thereto. Intermediate its length, the stem is provided with longitudinally adjustable stop nut 51, cooperating with the internal shoulder 23 of the plug to limit the outward movement of the stem in the plug, and usually packing washer 6, of asbestos, or other suitable material, is

' interposed between, shoulder 23, and said diameter of the spherical electrode. .tspherical electrode is spaced a distance from stop nut. The stem (and consequently the electrode 50) is held in place by the cap 7 removably fitting the outer end of the insulating plu and screwing on the rojecting end of t e stem. The end of the stem projecting beyond said cap is provided with a binding nut 8, by which theelectric conductor from the magneto, vibratin coil box or other suitable source of high requency electric current, while the return can be made through the shell and engine cylinder as usual or in some other suitable manner. The position of the electrode 50, with respect to the opposite electrode 12, and with respect to the end of the insulating skirt can be varied by separating the parts and changing the longitudinal position of the stop nut 51. The electrode 50, is preferably in the form of a smooth-surface s herical metal body or ball of less diameter t an the internal diameter of the annular opposingelectrode 12, and arranged concentrically w1th1n the same to form the annular spark gap a, within the annular electrode and around the spherical electrode. The.spher- 1cal electrode is so arranged with respect to the annular electrode that the plane of the annular electrode will be co-incident with a The e inner end-of the skirt of the insulating plug so that the inner open end of the compressed fluid chamber within said skirt is arranged opposite and adjacent to said spherlcal electrode and opens into the chamber within the inner end of the shell.

distributed around the is, without angular orsharp edges, points,

projections or roughness. When the opposing electrode surfaces are thus smooth and curved the sparks can jump in either direction across the spark gap, and the electrical energy is stored or held back to attain the high potential necessary to produce an exceedingly rich electrical discharge of high caloric value and efficiency for ignition purposes. I find that peculiarly a vantageous results and increased efliciency are attained in the operation of internal combustion engines by the employment of spark plugs or ignition devices embodying electrical condensers composed of the opposing electrodes and the intervening ignitlng spark gaps. With such a condenser, a spark gap of the desired width can be attained and even with an excess of oil and carbon on the condenser electrodes the exceedingly rich sparks are given off and the intensity thereof seems to be increased by the presence and combustion of the oil and carbon. To form the electrical condenser, the o posing surfaces of the electrodes are roundgd or curved, and to remove all fine points or roughness which might permit current leakage and thus prevent the condenser action, said'surfaces are burnished or olished as by application of suitable ely divided abras1ve and polishing material.

In the example shown, the two chamhas formed in the shell around and within the depending skirt 21, have annular outlets bustion thereof by the exceedingly rich sparks produced by the condenser.

It is evident that various modifications, variations, and changes might be resorted to, that elements or features might be added or other elements or features omitted, without departing from the spirit and scope of my invention and hence I do not wish to limit myself to the exact constructions shown.

the

nular rounded surface electrode, and an op-.

posing spherical electrode arranged therein and separated therefrom by an annular spark gap, said electrodes having smooth burnished surfaces.

3. An igniting device comprising an annular electrode rounded in icross section, and an opposing spherical electrode arranged therein and spaced therefrom to form an annular spark gap.

4. A spark plug having its shell formed at its open end with an internal smooth annular bead rounded in cross section and constituting an electrode, and an opposin smooth rounded surface electrode arrange therein and spaced therefrom to form an annular spark gap.

5. A spark plug havin an annular electrode, and a spherical e ectrode arranged ner open end and forming an electrode, an insulating plug arranged longitudinally within said shell and having a skirt forming chambers within the shell for the compressed charge, and a stem within said in-- sulating plug and provided with a spherical electrode arranged adjacent to the edge of said skirt and within said annular electrode and spaced therefrom by an annular spark gap forming the opening to said chambers,

substantially as described.

7 A spark plug comprising a shell having an internal annular electrode, an insulating plug arranged longitudinally within said shell and having a longitudinal skirt forming compressed charge chambers within the shell and around the skirt and within the skirt, and a conducting stem arranged longitudinally of said insulating plug and provided with a central rounded electrode within said annular electrode and spaced therefrom to form an annular spark gap, said central electrode forming annular outlets from said chambers, substantially. as described.

In testimony whereof I afiix my signature, in presence of two witnesses.

LOUIS BOND CHERRY Witnesses:

CoRA GERBERICH, RAY WEBB.

Images