US2120804A - Cylinder detector spark plug - Google Patents

Description

' June 14, 1938. G HANT OP ULOS 2,120,804

CYLINDER DETECTOR SPARK PLUG Filed Oct. 26, 1957 F 1 H 2 I7 ,9

INVENTOR.

BY George #007 'apou/as ATTORNEY.

Patented June 14, 1938 UNITED STATES PATENT, OFFICE 2 Claims.

The purpose of this invention is to provide means in combination with a spark plug for readily detecting the operation of a cylinder upon which the spark plug is used, in which the device is adapted to close a circuitfor operating a signal on the instrument board or at a remote point. p

The invention is a spark plug having a passage therethrough communicating with the interior of the cylinder, and also communicating with an auxiliary circuit closing device forming part of the spark plug.

The invention is an improvement over the device ofv my prior Patent Number 2,096,803, in that the circuit closing device is incorporated in a spark plug, thereby eliminating the necessity of providing an additional opening in the cylinder, and, at the same time, making the device adapted to be sold and installed in combination with the spark plug and forming a complete unit.

The object of this invention is, therefore, to provide means in a spark plug for closing a circuit by the pressure of a cylinder upon which the spark plug may be installed so that the circuit may operate a signal at a remote point.

Another object is to provide means for incorporating a circuit closing device in a spark plug without increasing the size of the plug.

Another object is to provide means for incorporating a circuit closing device in a spark plug without interfering with the eiiiciency of the plug.

A further object is to provide pressure operated circuit closing means, in combination with a spark plug, which may or may not be used as desired.

And a still further object is to provide pressure controlled circuit closing means in a spark plug without materially increasing the cost of the construction of the plug.

With these ends in view the invention embodies a spark plug having a point in a porcelain member mounted in a jacket, with a passage through the wall of the jacket, and a circuit closing device communicating with said passage and mounted upon said plug.

45 Other features and advantages of the invention will appear from the following description taken in connection with the drawing, wherein:

Figure 1 is a cross section through a spark plug showing the contact device extending upward 50 from the upper end thereof.

Figure 2 is a plan view of the device shown in Figure 1, showing an alternate design in which the contact device extends outward at an angle to the spark plug instead of extending radially there- 5 from.

Figure 3 is a sectional plan on line 33 of Fi ure 1.

Figure 4 is a view, similar to that shown in Figure 1, showing an alternate design in which the contact device is incorporated in the head of the spark plug.

Figure 5 is a sectional plan on line 5-5 of Figure 4, showing the contact operating mechanism.

Figure 6 is a sectional plan on line 66 show- 10 ing the opening in the spark plug, and also having part broken away showing the opening through a nut in the upper end of the spark plug.

In the drawing the device is shown as it may be made, wherein numeral i indicates the jacket 15 of the spark plug, numeral 2, the porcelain member in the center thereof, and numeral 3, an auxiliary cylinder forming the contact device.

The spark plug I may be made as shown in Figure 1, or as shown in Figure 4, however, in 20 the design shown in Figure 1, the porcelain 2 is secured in the jacket by a nut 4, and the contact extending through the spark plug is formed by a rod 5, which extends downward to a point 6 adjacent a point i which extends downward from 25 the lower end of the jacket I. The lower portion of the jacket I is threaded, as shown at the point 8, and these threads correspond with the threads of spark plugs now in use so that the spark plug may be screwed into the regular spark plug open- 30 ing. The lower portion of the jacket I is provided with an opening 9 which extends upward to a. circumferential recess l0, and a relatively small opening ll extends upward from the recess I0 to a projection I2 extending upward from the upper end of the jacket, and the projection I2 is provided with a threaded portion l3 upon which" the cylinder 3 may be screwed as shown.

The cylinder 3 is provided with a piston M, having piston rings l5 at one end and a stem I6 extending from the opposite end and also through the upper end ll of the cylinder. A spring l8 may be provided around the stem Hi to resiliently hold the piston M downward. At the upper end of the cylinder is a cap l9 having a contact point 20 therein, and the contact point extends through the cap forming a threaded stem or screw to which a wire may be attached for completing a circuit to a remote point, the opposite terminal at both ends being grounded. The cap I9 is made of insulating material, thereby insulating the point 20 from the ground. It will be noted that, as pressure in the cylinder increases, it will be transmitted through the openings 9, III and II to the cylinder 3, and this pressure will force the piston l4 upward and the piston will force the contact point I6 against the point 20. The cylinder wall may be provided with air openings 21 above the piston to equalize the pressure.

In the design shown in Figures 4, 5 and 6, the device is incorporated in the head of the spark plug which is formed with a casing 22 having a porcelain 23 similar to the porcelain 2, and this is provided with an inner rod 24 extending downward to a point 25 adjacent to another point 26 similar to the point 1. In this design the jacket is provided with an opening 21 extending upward through a passage 28, and in the upper end of the jacket is a nut 29 having a passage 30 therein which opens into a tubular member 3|, which is formed of relatively thin material and adapted to expand as the pressure therein increases. The opposite end of the member 3| is connected by a link 32 to a contact point 33 formed at the end of a spring 34, and extending into an opening 35 in a porcelain member 36, and it will be noted that, as the member 3| expanw, the link 32 will draw the point 33 inward, causing it to contact the inner end of a screw 31 extending into the opposite end of the porcelain, and connected by a member 38 to a screw 39 which extends through the wall of a cap 40, providing means for attaching a contact wire similar to the screw 2| of the design shown in Figure 1. The porcelain cylinder 36 is mounted upon the porcelain 23 by a clamp 4! held by a screw 42, and the inner end of the spring 34 is also held on the screw by a nut 43 as shown. The opposite side of the clamp 45 is provided with a strap 44 which extends around the porcelain cylinder 36 as shown. The cap 40 is mounted upon the porcelain 23, and this may be of insulating material, insulating the screw 39 from the jacket of the spark plug. In this design the porcelain 23 is held in the spark plug by an inner nut 45, similar to the nut 4 in the design shown in Figure 1, and the threads 46 at the lower end are similar to the threads 8, so that this spark plug may also be used in the usual spark plug opening.

It will be understood that other changes may be made without departing from the spirit of the invention. One of which changes may be in the use oi this device in combination with a spark plug of any other type or design, another may be in the use of other means for providing an open passage through the spark plug, and still another may be in the use of other means for incorporating a contact device in the head of a spark plug.

The construction will be readily understood from the foregoing description. In use the device may be provided as shown and described, and it will be noted that it may readily be screwed into the usual spark plug opening, and the contact screw at the upper end may be connected by a wire to a small light on the instrument board, or at any point, and, with the other terminal grounded through suitable current supplying means, the light will light when the cylinder explodes, or when the pressure reaches a predetermined amount; or it will not light if the pressure does not reach this amount, or if the cylinder does not fire. The device, therefore, makes it possible to readily indicate the performance of each cylinder of an internal combustion engine, so that the operator of the vehicle in which the device is installed may readily determine whether or not every cylinder is firing, and Whether or not the pressure in each cylinder is what it should be In the device shown in Figure 4, the entire upper part of the plug is assembled as a unit and may be removed from the jacket by unscrewing the nut 29, and this may be replaced with the points assuming their original positions.

Having thus fully described the invention, what I claim as new, and desire to secure by Letters Patent, is:

i. In a spark plug of the type having a metallic shell, with an insulating member extending through the central part thereof, and having

Images