Make-and-break spark plug

Claim 2

A make-and-break spark plug for piston engines comprising a spark plug housing equipped with means providing a counter electrode, a movable electrode positioned to cooperate with said counter electrode, said movable electrode and counter electrode forming therebetween a short-circuit path, an armature movably arranged within said spark plug housing, a magnetic coil for acting upon said armature, means for connecting said armature with said movable electrode, said armature including an end face directed away from said movable electrode, means providing a pressure equalization compartment within said spark plug housing at the region of said end face of said armature facing away from said movable electrode, the height of said pressure equalization compartment being greater than the height of said movable electrode, and means providing at least one bore for communicating said pressure equalization compartment with the interior of an engine cylinder associated with the spark plug, said means providing said at least one bore extending through said armature, said connecting means for said armature with said movable electrode, and through both of said electrodes.

Claim 3

A make-and-break spark plug for piston engines comprising a spark plug housing equipped with means providing a counter electrode, a movable electrode positioned to cooperate with said counter electrode, said movable electrode and counter electrode forming therebetween a short-circuit path, an armature movably arranged within said spark plug housing, a magnetic coil for acting upon said armature, means for connecting said armature with said movable electrode, said armature including an end face directed away from said movable electrode, means providing a pressure equalization compartment within said spark plug housing at the region of said end face of said armature facing away from said movable electrode, and means providing at least one bore for communicating said pressure equalization compartment with the interior of an engine cylinder associated with the spark plug, said means providing said at least one bore extending through said armature, said connecting means for said armature with said movable electrode, and through both of said electrodes, said movable electrode and said counter electrode possessing confronting contact surfaces forming therebetween said short-circuit path and possessing a substantially ring-shaped configuration.

Claim 4

A make-and-break spark plug for piston engines comprising a spark plug housing equipped with means providing a counter electrode, a movable electrode positioned to cooperate with said counter electrode, said movable electrode and counter electrode forming therebetween a short-circuit path, an armature movably arranged within said spark plug housing, a magnetic coil for acting upon said armature, means for connecting said armature with said movable electrode, said armature including an end face directed away from said movable electrode, means providing a pressure equalization compartment within said spark plug housing at the region of said end face of said armature facing away from said movable electrode, and means providing at least one bore for communicating said pressure equalization compartment with the interior of an engine cylinder associated with the spark plug, said means providing said at least one bore extending through said armature, said connecting means for said armature with said movable electrode, and through both of said electrodes, said movable electrode and said counter electrode possessing confronting contact surfaces forming therebetween said short-circuit path and possessing a substantially ring-shaped configuration.

Claim 5

The spark plug as defined in claim 1, further including an ignition circuit for such spark plug embodying thyristor means for producing ignition pulses.

Claim 6

The spark plug as defined in claim 1, wherein said armature and said movable electrode are arranged for substantially coaxial movement.

Claim 7

The spark plug as defined in claim 4, wherein said movable electrode is displaced away from said counter electrode in a direction away from said spark plug housing to break-up said short-circuit path.

Claim 8

A make-and-breaK spark plug for piston engines comprising a spark plug housing equipped with means providing a counter electrode, a movable electrode positioned to cooperate with said counter electrode, said movable electrode and counter electrode forming therebetween a short-circuit path, an armature movably arranged within said spark plug housing, a magnetic coil for acting upon said armature, means for connecting said armature with said movable electrode, said armature including an end face directed away from said movable electrode, means providing a pressure equalization compartment within said spark plug housing at the region of said end face of said armature facing away from said movable electrode, and means providing at least one bore for communicating said pressure equalization compartment with the interior of an engine cylinder associated with the spark plug, said means providing said at least one bore extending through said armature, said connecting means for said armature with said movable electrode, and through both of said electrodes, said movable electrode being displaced away from said counter electrode in a direction away from said spark plug housing to break-up said short-circuit path, said movable electrode extending past the periphery of said means for connecting said armature with said movable electrode, said movable electrode incorporating a protruding marginal portion which in the rest position of said movable electrode bears against a neighboring end contact surface of said spark plug housing providing said counter electrode, said bore being provided at said armature, at said connecting means and at said movable electrode to permit the pressure prevailing in the engine cylinder to be transmitted to said pressure equalization compartment and to thus support the axial movement of said movable electrode, and ignition circuit means for delivering thyristor-controlled current pulses as a function of the rotational speed of the engine to the magnetic coil, so that between the movable electrode and said neighboring end contact face of said spark plug housing there exists an ignition spark which continuously wanders upon the surface of said movable electrode.

Claim 9

A make-and-breaK spark plug for piston engines comprising a spark plug housing equipped with means providing a counter electrode, a movable electrode positioned to cooperate with said counter electrode, said movable electrode and counter electrode forming therebetween a short-circuit path, an armature movably arranged within said spark plug housing, a magnetic coil for acting upon said armature, means for connecting said armature with said movable electrode, said armature including an end face directed away from said movable electrode, means providing a pressure equalization compartment within said spark plug housing at the region of said end face of said armature facing away from said movable electrode, and means providing at least one bore for communicating said pressure equalization compartment with the interior of an engine cylinder associated with the spark plug, said means providing said at least one bore extending through said armature, said connecting means for said armature with said movable electrode, and through both of said electrodes, said movable electrode being displaced away from said counter electrode in a direction away from said spark plug housing to break-up said short-circuit path, said movable electrode extending past the periphery of said means for connecting said armature with said movable electrode, said movable electrode incorporating a protruding marginal portion which in the rest position of said movable electrode bears against a neighboring end contact surface of said spark plug housing providing said counter electrode, said bore being provided at said armature, at said connecting means and at said movable electrode to permit the pressure prevailing in the engine cylinder to be transmitted to said pressure equalization compartment and to thus support the axial movement of said movable electrode, and ignition circuit means for delivering thyristor-controlled current pulses as a function of the rotational speed of the engine to the magnetic coil, so that between the movable electrode and said neighboring end contact face of said spark plug housing there exists an ignition spark which continuously wanders upon the surface of said movable electrode.

Claim 10

A make-and-break spark plug for piston engines comprising a spark plug housing equipped with means providing a counter electrode, a movable electrode positioned to cooperate with said counter electrode, said movable electrode and counter electrode forming therebetween a short-circuit path, an armature movably arranged within said spark plug housing, a magnetic coil for acting upon said armature, means for connecting said armature with said movable electrode, said armature including an end face directed away from said movable electrode, means providing a pressure equalization compartment within said spark plug housing at the region of said end face of said armature facing away from said movable electrode, and means providing at least one bore for communicating said pressure equalization compartment with the interior of an engine cylinder associated with the spark plug, said means providing said at least one bore extending through said armature, said connecting means for said armature with said movable electrode, and through both of said electrodes, said armature being provided with a central bore, said connecting means comprising a through-bored rod member seated in said central bore and connected with said movable electrode.

Claim 11

A make-and-break spark plug for piston engines comprising a spark plug housing equipped with means providing a counter electrode, a movable electrode positioned to cooperate with said counter electrode, said movable electrode and counter electrode forming therebetween a short-circuit path, an armature movably arranged within said spark plug housing, a magnetic coil for acting upon said armature, means for connecting said armature with said movable electrode, said armature including an end face directed away from said movable electrode, means providing a pressure equalization compartment within said spark plug housing at the region of said end face of said armature facing away from said movable electrode, and means providing at least one bore for communicating said pressure equalization compartment with the interior of an engine cylinder associated with the spark plug, said means providing said at least one bore extending through said armature, said connecting means for said armature with said movable electrode, and through both of said electrodes, said armature being provided with a central bore, said connecting means comprising a through-bored rod member seated in said central bore and connected with said movable electrode.

Claim 12

The spark plug as defined in claim 7, wherein said movable electrode consists of a substantially ring-shaped member having a radially extending web to which there is secured said rod member.

Claim 13

A make-and-break spark plug for piston engines comprising a spark plug housing equipped with means providing a counter electrode, a movable electrode positioned to cooperate with said counter electrode, said movable electrode and counter electrode forming therebetween a short-circuit path, an armature movably arranged within said spark plug housing, a magnetic coil for acting upon said armature, means for coNnecting said armature with said movable electrode, said armature including an end face directed away from said movable electrode, means providing a pressure equalization compartment within said spark plug housing at the region of said end face of said armature facing away from said movable electrode, and means providing at least one bore for communicating said pressure equalization compartment with the interior of an engine cylinder associated with the spark plug, said means providing said at least one bore extending through said armature, said connecting means for said armature with said movable electrode, and through both of said electrodes, said electrode being formed of a high molecular weight material having a melting point exceeding 3,000* C.

Claim 14

A make-and-break spark plug for piston engines comprising a spark plug housing equipped with means providing a counter electrode, a movable electrode positioned to cooperate with said counter electrode, said movable electrode and counter electrode forming therebetween a short-circuit path, an armature movably arranged within said spark plug housing, a magnetic coil for acting upon said armature, means for coNnecting said armature with said movable electrode, said armature including an end face directed away from said movable electrode, means providing a pressure equalization compartment within said spark plug housing at the region of said end face of said armature facing away from said movable electrode, and means providing at least one bore for communicating said pressure equalization compartment with the interior of an engine cylinder associated with the spark plug, said means providing said at least one bore extending through said armature, said connecting means for said armature with said movable electrode, and through both of said electrodes, said electrode being formed of a high molecular weight material having a melting point exceeding 3,000* C.

Claim 15

The spark plug as defined in claim 9, wherein said electrode is formed of a material selected from molybdenum and molybdenum alloys.

Claim 16

The spark plug as defined in claim 1, wherein said housing of said spark plug is constructed as a bipartite member, one part of which houses said magnetic coil, whereas the other part of which is an exchangeable housing portion which can be threadably connected with the engine cylinder and can be replaced after pronounced burn-off of the movable electrode.

Claim 17

An ignition system for piston engines comprising a power source, a distributor in circuit with said power source, a number of spark plugs corresponding to the number of cylinders of the engine, transformer means for stepping up the voltage of the power source so as to exceed 30 volts, said spark plugs comprising make-and-break spark plugs, each such spark plug including a magnetic coil and a movable electrode and a cooperating counter electrode forming therebetween a short-circuit path, a thyristor in circuit with the magnetic coil of each spark plug and said transformer means for periodically connecting in pulse-like fashion as a function of the rotational speed of the engine said transformer means with the series circuit consisting of the magnetic coil of the associated spark plug and the breakable short-circuit path between the movable electrode and the counter electrode.

Claim 18

An ignition system for piston engines comprising a power source, a distributor in circuit with said power source, a number of spark plugs corresponding to the number of cylinders of the engine, transformer means for stepping up the voltage of the power source so as to exceed 30 volts, said spark plugs comprising make-and-break spark plugs, each such spark plug including a magnetic coil and a movable electrode and a cooperating counter electrode forming therebetween a short-circuit path, a thyristor in circuit with the magnetic coil of each spark plug and said transformer means for periodically connecting in pulse-like fashion as a function of the rotational speed of the engine said transformer means with the series circuit consisting of the magnetic coil of the associated spark plug and the breakable short-circuit path between the movable electrode and the counter electrode.