US3181523A

US3181523A - Spark plug cover

Info

Publication number: US3181523A
Application number: US324680A
Authority: US
Inventors: Robert W Casey
Original assignee: Individual
Current assignee: Individual
Priority date: 1963-11-19
Filing date: 1963-11-19
Publication date: 1965-05-04
Anticipated expiration: 1982-05-04

Description

y 1965 R. w. CASEY 3,181,523

SPARK PLUG COVER Filed NOV. ].9, 1963 INVENTOR F0 5527- VV. 64555/ A 7" TOE/YE Y United States Patent 3,181,523 SPARK PLUG COVER Robert W. Casey, 2362 N. 49th St, Milwaukee, Wis. Filed Nov. 19, 1963, Ser. No. 324,680 2 Claims. (Cl. 123-198) This invention relates to a cover for a spark plug of an internal combustion engine.

Many internal combustion engine powered devices commonly found around the home, such as lawn mowers and snow blowers, are not provided with an ignition lock or other device for preventing operation of the engine. This presents a hazard to children who may be inclined to tamper with the device and either accidently or intentionally start the engine and injure themselves on one of the moving parts.

The primary object of this invention is to provide a cover for a spark plug from which the ignition lead has been disconnected which may be locked to prevent operation of the engine. Another object of the invention is to provide such a cover which is effective and yet simple and economical to manufacture.

In the present invention the cover is comprised of two parts. One part is at all times secured to the cylinder head by the spark plug and the other is removably engageable with the first part. Finally means are provided to permit the two parts to be locked in engagement with each other.

The invention is illustrated in a preferred embodiment in the accompanying drawing in which:

FIG. 1 is a fragmentary side elevation of an internal combustion engine showing both parts of the spark plug cover in place and locked in engagement with a padlock.

FIG. 2 is an enlarged portion in section of the spark plug, both parts of the cover and padlock as shown in FIG. 1.

FIG. 3 is a view similar to FIG. 2 showing the padlock and removable cover part removed and the ignition lead connected for normal operation of the engine.

FIG. 4 is a perspective view of the two parts of the spark plug cover in spaced relation with a portion of the cover part normally secured to the cylinder head broken away.

Referring to the drawings, a spark plug 1 is threaded into the cylinder head 2 of an internal combustion engine 3. The ignition lead 4 is connected to the spark plug 1 during operation of the engine 3. Disposed between the spark plug 1 and the cylinder head 2 is a gasket 5 and a first cover part 6. The first cover part 6 is of generally tubular shape, having an axially extending, circumferentially continuous side wall portion 7 and an end portion 8 at one end in which an opening is provided through which the threaded base portion of the spark plug 1 passes. Also associated with the first cover part 6 is a transverse, outwardly extending member 9 which has an opening 10 therein. The second cover part 11 is of tubular shape having an axially extending, circumferentially continuous side wall portion 12 and one closed end portion 13 and a transverse, outwardly extending member 14 with an opening 15 therein. The side wall portion 12 of the second cover part 11 is adapted to slidingly engage the side wall portion 7 of the first cover part 6 after the ignition lead 4 has been disconnected from the spark plug 1. Once the

side wall portions

7 and 12 of the cover parts 6 and 11 have been engaged, the transverse members 9 and 14 are adapted to be positioned with their

respective openings

16 and 15 in alignment to permit the staple 16 of a padlock 17 to be passed through said openings 1d and 15 so as to lock the cover parts 6 and 11 in mutual engagement.

The cover parts 6 and 11 may be made of any relatively non-resilient material. The cover part 6 must be capable of withstanding the temperatures achieved by the cylinder head 2 and spark plug 1 during operation of the engine. Steel had been found to be a particularly suitable material for both cover parts 6 and 11.

In the embodiment of the invention shown in the accompanying drawing limited axial movement of the cover part 11 with respect to the cover part 6 is possible with the padlock 17 in locking position. Thus, the cover parts 6 and 11 must engage each other a sufi'icient depth and their mutually engaging

side wall portions

7 and 12,

respectively, must be of sufiiciently close tolerances so as not to permit the cover part 11 to be pried oil the cover part 6. Other embodiments of the invention are possible which will reduce'or prevent this limited relative axial movement of the cover parts 6 and 11 when in locked position, as will appear to those skilled in the art. For example, simply disposing the transverse members 9 and 14 in a plane including the axis of the cover parts 6 and 11 will greatly reduce the amount of possible relative axial movement of the cover parts 6 and 11 when the padlock 17 is in locking position.

It should be noticed in the embodiment of the invention shown in the accompanying drawing that the side wall portion '7 of the cover part 6 adjacent the cylinder head 2 is of reduced diameter. This is not always necessary depending upon the dimensions of the spark plug 1 and the cylinder head 2. There should be sutficient clearance between the side wall portion 7 of the cover part 6 and the spark plug 1 to permit the use of a standard spark plug wrench to tighten the spark plug 1. Otherwise, the side wall portion 7 of the cover part 6 may be of any suitable shape which will allow clearance between it and the spark plug 1 and cylinder head 2.

Also, in the embodiment shown the transverse members 9 and 14 are integral with the cover parts 6 and 11, respectively. The

transverse members

8 and 12 may be formed from separate pieces which may be secured to the

side wall portions

7 and 12 of the cover parts 6 and 11, respectively, by any suitable means such as by rivets or other fasteners or by welding or brazing.

Since many possible embodiments may be made in the invention and many changes might be made in the embodiment herein shown and described, as will appear to those skilled in the art, it is to be understood that the foregoing is to be interpreted as illustrative and not in a limiting sense.

What I claim is:

1. A cover for a spark plug of an internal combustion engine from which spark plug the ignition lead has been disconnected comprising first and second slidingly engageable tubular cover parts; said first tubular cover part being the one of smaller diameter and extending less than the normally exposed length of said spark plug and having a relatively fiat transverse member extending outwardly from the medial portion thereof and an end portion at one end thereof, said end portion having a central aperture therein slightly larger than the outer diameter of the threaded base portion of said spark plug whereby said first tubular cover part may be secured to the cylinder head of said internal combustion engine by said spark plug; said second tubular cover part being closed at one end and having a relatively flat transverse member extending outwardly adjacent the other end thereof; said transverse members being disposed in planes normal to the axes of said first and second tubular cover parts and having aligned openings therein through which may be passed the staple of a padlock thereby preventing substantial relative axial movement of the engaged said first and second tubular cover parts.

2. A cover for a spark plug of an internal combustion engine from which spark plug the ignition lead has been 3 disconnected comprising a first cover part and a second cover part; said first cover part having an axially extending, continuous side Wall portion and an end portion at one end with an opening therein slightly larger than the outer diameter of the threaded base portion of said spark plug; said second cover part having an axially extending, continuous side wall portion and one closed end portion; said side Wall portions of said first and second cover par-ts being slidingly engageable; and locking means for preventing substantial relative axial movement of the engaged side Wall portions of said first and second cover parts comprising at least one pair of transverse, out- References Cited by the Examiner V UNITED STATES PATENTS 1,353,959 9/20 Holst 123-146.5 1,511,001 10/24 Padden l23198 2/39 Meredith 123169.1

FRED E. ENGELTHALER, Primary Examiner.

Claims

1. A COVER FOR A SPARK PLUG OF AN INTERNAL COMBUSTION ENGINE FROM WHICH SPARK PLUG THE IGNITION LEAD HAS BEEN DISCONNECTED COMPRISING FIRST AND SECOND SLIDINGLY ENGAGEABLE TUBULAR COVER PARTS; SAID FIRST TUBULAR COVER PART BEING THE ONE OF SMALLER DIAMETER AND EXTENDING LESS THAN THE NORMALLY EXPOSED LENGTH OF SAID SPARK PLUG AND HAVING A RELATIVELY FLAT TRANSVERSE MEMBER EXTENDING OUTWARDLY FROM THE MEDIAL PORTION THEREOF AND AN END PORTION AT ONE END THEREOF, SAID END PORTION HAVING A CENTRAL APERTURE THEREIN SLIGHTLY LARGER THAN THE OUTER DIAMETER OF THE THREADED BASE PORTION OF SAID SPARK PLUG WHEREBY SAID FIRST TUBULAR COVER PART MAY BE SECURED TO THE CYLINDER HEAD OF SAID INTERNAL COMBUSTION ENGINE BY SAID SPARK PLUG; SAID SECOND TUBULAR COVER PART BEING CLOSED AT ONE END AND HAVING A RELATIVELY FLAT TRANSVERSE MEMBER EXTENDING OUTWARDLY ADJACENT THE OTHER END THEREOF; SAID TRANSVERSE MEMBERS BEING DISPOSED IN PLANES NORMAL TO THE AXES OF SAID FIRST AND SECOND TUBULAR COVER PARTS AND HAVING ALIGNED OPENINGS THEREIN THROUGH WHICH MAY BE PASSED THE STAPLE OF A PADLOCK THEREBY PREVENTING SUBSTANTIAL RELATIVE AXIAL MOVEMENT OF THE ENGAGED SAID FIRST AND SECOND TUBULAR COVER PARTS.