DE2058918A1 - Spark plug with internal resistance - Google Patents

Description

Dlpl.-lng. R. H. B A K ft

Dlpl.-Phys. E. RETZLER
DTpUr.g. W. H? ';: ·; - ■' ^% HK ~ \ itmPOHL

3 & .rM970

MO 2572

CHAMPION SPARK PLTJG COMPANY, Toledo, Ohio, / USA

Spark plug with internal resistance

The invention relates to a spark plug and its application this spark plug on internal combustion engines.

The use of resistors in the high voltage part of a Ignition systems, for example for motor vehicles, to Suppressing the occurrence of high frequencies, in particular radio frequencies, is known per se. Such resistance are either distributed in ignition cables or arranged at one or more fixed points in the ignition system, for example in spark plugs, in ignition cable lugs, in the distributor cap or in the distributor rotor. If a suppression avi-der *. stood in a fixed position, it becomes common uses a spring to electrically connect one end of the resistor to an adjacent terminal. The spring compensates

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sets tolerances in the assembled parts and ensures good electrical contact under all working conditions. Well-known springs were chosen from spiral coil springs and thus form inductors, which are resonance circles with the capacity of the ignition system. Bach of excitement through spark discharges swings this circle and emits strong radio frequency or radio frequency signals. The values of capacitance and inductance are usually such that the emitted signals have a frequency which falls in the part of the frequency spectrum that is used for radio propagation or other related fields are used, thereby causing undesirable interference.

According to the invention, an improved spring with low inductance is to be proposed in order to act as a radio interference suppression resistor to be installed in an ignition system, in particular an internal combustion engine

The main factor here is the inductance in the ignition system for an internal combustion engine can be reduced to reduce the likelihood of radio frequency interference to diminish.

According to the invention, a spring is used to achieve this, to mount a resistor in the bore of a spark plug or other suitable location in an ignition system. The spring is capable of being resilient, mechanical and electrical perform storage functions with minimal inductance, thereby reducing the likelihood of undesirable High frequency or radio frequency phenomena occur, For this purpose, the spring is formed from an elongated piece of resilient, conductive material, which is preferably has a rectangular or flat cross-section. The elongated piece of material has a number of reciprocating folds or bends that are similar to the folds are formed in the bellows of an accordion. The opposing parts of the compressed spring

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run in parallel ■ and ensure good electrical contact with the end fault resistance and with a neighboring one Terminal or an adjacent terminal · Since the spring is not coiled or coiled, the self-inductance of the leather minimal, regardless of their state of compression. That The problem that the spring forms a resonance circuit with a capacitance of the ignition system is therefore reduced to a minimum.

Exemplary embodiments of the invention will now be based on of the accompanying drawings are explained in more detail in those

1 shows a partial section through a spark plug with an interference protection resistor and a spring according to the invention;

FIG. 2 is a cross section taken along line 2-2 in FIG. 1 in a larger representation;

Fig. 3 is a view of a spring after being mitigated;

Fig. 4 is a side view of a spring according to the invention;

and FIG. 5 is an enlarged view showing a Spring according to the invention, which is compressed between a spark plug electrode and an interference protection resistor.

In Figs. 1 and. 2 shows a spark plug 10 which has a spring 11 according to the invention. The spark plug 10 generally includes an outer housing 12 having a lower threaded end 13, which is in the head of an internal combustion engine is screwed in, as well as an insulator 14. The insulator 14, which is mounted within the housing 12, has an axial bore 15 for mounting a center electrode 16. The Mittelelektoirde 16 has an ignition tip 17, the one Spark gap forms with a ground electrode 1S, which is attached to the

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BATH ORIGINAL

deende 13 of the housing 12 is attached. The center electrode 16 is electrically in series across the spring 11 and one Interference protection resistor 19 is connected to a connecting bolt 20. The resistor 19 can, for example, consist of a conventional carbon resistor or one wound from wire Resistance. The spring 11 presses the resistor 19 against the outer terminal 20 and thus holds one electrical contact between the resistor 19 and the terminal or the connecting bolt 20 upright to simultaneously to bring about an electrical contact between resistor 19 and electrode 16. Good electrical contact is made through maintaining the spring 11, although the electrode 16 and the resistor 19 expand and contract during the heating and cooling of the spark plug 10. Although the Spring 11 is shown between the resistor 19 and the central electrode 16, the spring 11 can be similar Way be positioned between the resistor 19 and the connecting bolt 20.

Referring to Figures 3 to 5 of the drawings, the spring 11 is more specific shown. Although the spring 11 can be made from a resilient wire, it is preferred to manufacture it of an elongated resilient piece of conductive material with a substantially flat or rectangular cross-section according to the illustration. The spring 11 has two opposite end portions 21 and 22 and a plurality thin and backward bends 23, which have a multitude of of intermediate side parts 24 form. The bends 23 guided to and fro and the side parts 24 are similar Way like folds formed in the bellows of an accordion. Although the spring 11 according to the illustration four has back and forth bends 23, the three Forming intermediate side parts 24, the spring 11 can of course have either fewer or more bends 23 to have fewer or additional side parts 24 to build. The bends 23 are preferably under

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stood arranged to form uniform side panels 24. As FIG. 4 shows, the side profile of the leather 11, if it is now in the compressed or decompressed state, is flat. The low profile reduced in considerable ¥ _e ise the inductance of the spring 11, after Mg. 5, the spring 11 is compressed between the electrode 16 and resistor 19 shown. End 21 of spring 11 is kept in substantially flat contact with electrode 16 while end 22 is kept in substantially flat contact with resistor 19, thereby maintaining a good electrical connection between electrode and resistor 19.

Although the spring 11 is built into a spark plug 10 for an internal combustion engine is shown, of course, the spring 11 for mounting resistors in other places be arranged in the ignition system for an internal combustion engine. It has been found, for example, that an interference suppressor stood in the distributor rotor or the distributor cap of an internal combustion engine. One the Resistance receiving bore is then formed in the rotor or cap and one end of the resistor is against one Clamp positioned. The spring 11 is then used to connect the / end of the resistor to a second terminal. The spring 11 can be used in a similar way to accommodate a noise suppression resistor in a terminal, that connects an ignition cable to a spark plug. In each of these cases, the spring 11 sets in considerable Reduce the inductance of the ignition system via a system in which a standard coil spring is used an interference protection resistor or a radio interference suppression resistor to store.

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Claims (7)

Pat en t claims M.! Spark plug for an internal combustion engine with a central electrode surrounding insulator, this electrode having an external terminal or an external connection via a Resistor is connected, which is arranged within the bore of this insulator, characterized by a spring (11) low inductance, which makes the electrical contact between this resistor (ig) this electrode (16) and this connecting bolt (20) maintains, this spring (11) consists of an elongated resilient conductor and this conductor a plurality of bends (23) going back and forth in the longitudinal direction over the bore 15 of this insulator (H) has, its maximum compressed width being less than the diameter of the bore of this insulator, and this spring being positioned in the bore (15) of this insulator (H) and between the resistor (I9) and either Electrode or clamp or connecting bolt is pressed together. 2. Spark plug according to claim 1, characterized in that the Spring is formed from a flat elongated conductor. 3. Spark plug according to claim 2, characterized in that one end (22) of this spring is designed so that it makes flat contact with one end of this resistor (19) and that the other end (21) of this spring is so formed is to maintain flat contact with one end of either this electrode (16) or this clip will. 4. Spark plug for an internal combustion engine according to claim 2, characterized in that the back and forth bends (23) are essentially uniform and uniform at a distance along this conductor (11) according to Art the folds of an accordion are arranged. 109829/105? 5. Use of the spark plug according to one of the preceding Claims for an ignition system of an internal combustion engine with radio interference suppression, ^ denoted by a spring lower Inductance to electrically connect this resistor to a terminal or a terminal, this spring from a elongated resilient conductor and this conductor has a plurality of reciprocating bends that are in whose longitudinal direction are arranged at a distance similar to accordion folds, this spring between this resistance and this clamp is compressed and the end portions of this Springs are designed to maintain shallow contact with that resistor and clip. 6. Use according to claim 5, wherein the spring has an interference suppression resistor connects in an ignition system for an internal combustion engine, characterized in that the spring consists of a flat elongated conductor is formed. 7. Application according to claim 5, wherein the low inductance spring for connection to an interference suppression resistor in one Ignition system is designed for an internal combustion engine, characterized in that the bends going back and forth are formed substantially uniformly and spaced along this conductor. 109829/105? Blank page