US2464533A

US2464533A - Positive contact ignition assembly

Info

Publication number: US2464533A
Application number: US749485A
Authority: US
Inventors: Thomas R Shearer
Original assignee: Individual
Current assignee: Individual
Priority date: 1947-05-21
Filing date: 1947-05-21
Publication date: 1949-03-15
Anticipated expiration: 1966-03-15

Description

March 15, 1949. 'r. R. SHEARER POSITIVE CONTACT IGNITION ASSEMBLY Filed May 21. 194i 1 Can-1 FIG-"'5 Thom s '2. Shearer {Enveabor Qtborneg Patented Mar. 15, 1949 lclnim.

invention relates toignition systems of.

internal combustion engines and, more speciflcally. to improvements in distributors and spark plug ignition connectors for automobiles.

It is well known that the condition of the ignition system of an internal combustion engine is a very important factor in achieving high engine efliciency and satisfactory operation. Yet, the units now on the market are subject to -many troubles which interfere with engine operation, particularly during adverse weather conditions or after a prolonged driving period. For example. the ignition cables leading into the distributor begin to corrode at the ends and lose their effectiveness in providing good electrical contact. The same is true with the spark plug ends of the cables, and such conventional connections are readily shorted by small quantities of water which may be splashed or blown in under the hood of the car. Also, the rotor and inner distributor contacts are readily corroded or burned out by arcing, and combustion eiiiciency is reduced considerably thereby.

It is the purpose of this invention to eliminate such detrimental conditions and to provide an ignition system which will give high ethciency and maintain such high efllciency over extended periods of time.

The invention may be more readily understood by reference to the drawing in which Figure 1 shows a cross-sectional side view of a distributor cap and rotor employing features of the present invention; Figure 2 is a side view, partly in cross section, of the spark plug connection. of the present invention, while Figure 3 is a bottom view of an inner distributor contact provided with a clip ofthe present invention.-

Referring again to the drawing, numeral I represents a distributor cap, generally made of insulating plastic, and having a series of wells 2 around the upper part for housing the ends of the ignition cables II. also provided on the to for housing the end of the cable leading to the fixed contact H of rotor l0. Molded into the bottom of wells 2 and central well 3 are metal (copper or brass) contacts 8 and contact 8 respectively, which contact clips I! attached to the ends of cables I] and through which are threaded and spread out the inner stranded copper wires IQ of thecables. Contacts 5 extend (by means of sections 4) through the top of the cap and terminate with contacts I which make electrical contact with moving contact I! of rotor i0. Likewise, con tact I projects by means of section 8 through A central well 3 is the center of the cap and terminates with a button contact on which rides stationary contact ll of rotor l0. Heretofore, there has been a space between well 2 and cable H which allowed ingress of water, dust, and the like and these elements gradually accelerated the corrosion of the ends of wires I! and clips l0, resulting in rapid loss'in emc'iency of the contact. This difficulty has been eliminated in the present invention by providing a movable sleeve I8 of soft or resilient rubber or plastic which may be slid into the space between the well and the outside of the cable, thereby sealing the otherwise exposed air space.

Another difflculty, previously mentioned, has been the poor contact, during service, obtained between rotor contact I5 and contacts 6 of the cap. This has been attributed to the fact that contact I5 is usually of steel while'contacts 6 are of copper. Both of these metals tend to fuse and spatter on arcing and they both tend to corrode considerably in presence of moisture, which effects greatly reduce their contact efllciency One feature of the present invention is to eliminate these conditions by making contact.

with a contact surface of molybdenum which has been found to be highly resistant to burning or spattering by high voltage arcs and to atmospheric corrosion accelerated by the presence of ozone created by the arc.

This molybdenum surface I may be attached to contacts 6 by metal cladding or spot welding of a sheet of molybdenum on contact 6 (afterthe latter has been reduced in thickness by millin grinding or filing to allow for the insertion of the molybdenum sheet or strip and still maintain proper clearance with relation to rotor contact l5). However, it 'is preferableto employ clips 33 of molybdenum which may be slipped over contacts 6. These clips preferably comprise a strip of molybdenum of Qt" or ,4 thickness, more or less, and are shaped to provide substantially flat portion 1 contacting rotor contact i5, and concavely curved or circular arc sections 33 which grip the back portion of contact 6. Space 34 is provided to allow for variations in dimensions of the periphery of contact 6. These clips are slipped over contacts 6 and are held in place due to the tension at curved ends 33. As to the rotor contact, it is preferred to'employ a strip of molybdenum l5 which is maintained inelectrical contact with spring arm 13 by rivet I 4. However, it is possible to weld or clad or otherwise attach a strip of molybdenum only on the contacting tip of strip I5, the tip preferably being rounded to conform to the arc of travel of the rotor.

To eliminate difliculties with spark plug connections, end 28 of ignition cable 29 has attached thereto clip 21 from the center of which pro trude wire ends I 9. This end bearing the clip is inserted in the upper portion 25 of the double connector 28, the bottom portion 23 of which is clippedonto the spark plug terminal 22.

Sections

25 and 23 of the double connector 26 are joined together, although there is usually provided a central opening between the two sections to allow for egress of air, etc. Over this whole assembly is slipped a flexible sleeve 30 of rubber, plastic or other insulating material, the sleeve being long enough to adequately cover the upper ends of the connections and tight enough to snugly fit over the outside of the cable 29. The lower end of the sleeve extends over the bottom ends of the connections and terminates at about the half-way portion 2 I .of the insulator on spark plug 20, the lit being a-snug one. However, the sleeve should not extend too far down the plug as to become burned by the heat. By this means, moisture, dust, corrosive gases, and other interfering elements are kept out of the contact surfaces, thereby maintaining a high' contact efiiciency.

By means of the molybdenum contacts provided in the distributor, arcing is greatly elimihated, and particularly, vaporization of the metal is reduced and consequent wear at the arc, which results in poor starting. By means of the plastic sleeves, moisture and other corrosive and foreign agents are kept out away from the contact surfaces, giving positive contact for considerably long periods of time. These sleeves are easily in stalled. The spark plug end is slipped over the plug and the end of the sleeve, which usually is curled under, is pulled up by flexing the rubber, and then allowed to snap back inte place.

With an assembly such as that described, it has been possible to travel 50ml miles easily with out any visible evidence oi. burning of contacts or corrosion. Due to the high contact efliciency maintained. it has been found that the life of the condenser is extended considerably thereby. The eflectiveness oi! this assembly is evidenced by the fact that ease in starting, pick-up, and mileage improvement remain practically undiminished for long driving periods, and a noticeable diiierence in getaway and hotter spark are observed when a change is made from the conventional assembly to that of the present invention. Also, by actual experience, it has been found that the distributor make-and-break points have shown no burning or pitting over extended periods of driving time.

I claim:

In a distributor-to-cable-to-spark plug ignition system employing wells projecting from the top of the distributor cap for housing the cable ends. semicircular distributor cap contacts intermittently contacting a rotating rotor contact, and a double connector snapping on the spark plug terminal and holding an endof the cable, the improvement comprising a D-shaped molybdenum strip, broken atthe curved portion and slightly curved at the broken ends to provide tension and forming a secure, snug fitting clip over each semi-circular distributor cap contact.

THOMAS R. SHEARER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,338,989 Lang May 4, 1920 1,569,224 Berthold Sept. 23, 3924 1,658,713 Ir'liliei' Feb. 7, 1928 1,898,6i6t Ridge Feb. 21, 1933 2,1616% Spengler Aug. 1, 1939 2,253,221 Barnum et al Aug. 19, 194i 2,3 ifi,455 Hartzeli Mar. 7, i944