Contactless ignition system

Claim 2

Electromagnetic transducing apparatus comprising, a cylindrical magnet surrounded about its axis by a coil of wire, and substantially planar pole pieces affixed to the ends of said cylindrical magnet, said pole pieces being tapered and aligned with their tips along a line for facing one edge at a time of a cam made of magnetic material for rotation about an axis thereof, whereby rotation of said cam produces a sequence of sharp pulses across said coil of wire as each edge of the said cam passes closely adjacent to said tips.

Claim 3

Electromagnetic transducing apparatus in accordance with claim 1 and further comprising a bobbin for carrying said coil and maintaining said pole pieces and said magnet in alignment

Claim 4

Electromagnetic transducing apparatus in accordance with claim 1 and further comprising a housing for supporting said transducing apparatus with the ends of said pole pieces closely adjacent to the path traveled by a distributor cam.

Claim 5

Electromagnetic transducing apparatus in accordance with claim 1 wherein said pole pieces are beveled at their tips.

Claim 6

Electromagnetic transducing apparatus in accordance with claaim 2 and further comprising a housing carrying said bobbin, magnet and pole pieces with the tips of said pole pieces closely adjacent to the path traveled by the circumferential edge of a rotating distributor cam when said housing is seated in the place ordinarily occupied by mechanical ignition points.

Claim 7

Electromagnetic transducing apparatus in accordance with claaim 2 and further comprising a housing carrying said bobbin, magnet and pole pieces with the tips of said pole pieces closely adjacent to the path traveled by the circumferential edge of a rotating distributor cam when said housing is seated in the place ordinarily occupied by mechanical ignition points.

Claim 8

Electromagnetic transducing apparatus comprising, a cylindrical magnet surrounded about its axis by a coil of wire, substantially planar pole pieces affixed to the ends of said cylindrical magnet, first and second leads from said coil, an operational amplifier having a common terminal, a summing junction and an output terminal and a predominantly resistive feedback impedance intercoupling said summing junction and said output terminal, said first and second leads being connected to said summing junction and said common terminal respectively.

Claim 9

Electromagnetic transducing apparatus comprising, a cylindrical magnet surrounded about its axis by a coil of wire, substantially planar pole pieces affixed to the ends of said cylindrical magnet, first and second leads from said coil, an operational amplifier having a common terminal, a summing junction and an output terminal and a predominantly resistive feedback impedance intercoupling said summing junction and said output terminal, said first and second leads being connected to said summing junction and said common terminal respectively.

Claim 10

Apparatus in accordance with claim 6 and further comprising, saturable amplifier means having its input coupled to said operational amplifier output for providing a signal for controlling the current in the spark coil of an ignition system.

Claim 11

Apparatus in accordance with claim 7 and further comprising a high voltage transistor responsive to the signal provided by said saturable amplifier means for controlling the current in the spark coil of an ignition system.

Claim 12

Apparatus in accordance with claim 8 and further comprising overvoltage protection means including diode means for preventing excessive base to emitter voltage of said high voltage transistor and a resistor in series with a breakdown device for preventing excessive collector to emitter voltage of said high voltage transistor.

Claim 13

Electromagnetic transducing apparatus comprising, a cylindrical magnetic surrounded about its axis by a coil of wire, substantially planar pole pieces affixed to the ends of said cylindrical magnet, first and second leads from said coil of wire, a common terminal, a transistor having at least base, emitter and collector electrodes, said first and second leads being connected to said common terminal and said emitter respectively.

Claim 14

Electromagnetic transducing apparatus comprising, a cylindrical magnetic surrounded about its axis by a coil of wire, substantially planar pole pieces affixed to the ends of said cylindrical magnet, first and second leads from said coil of wire, a common terminal, a transistor having at least base, emitter and collector electrodes, said first and second leads being connected to said common terminal and said emitter respectively.

Claim 15

Apparatus in accordance with claim 10 and further comprising means for interconnecting said coil of wire and said transistor so that the direct current flowing through said coil produces a magnetic field that reinforces the magnetic field established by said magnet.

Claim 16

Apparatus in accordance with claim 11 and further comprising a resistor from the transistoR collector to the transistor base for biasing said transistor.

Claim 17

Apparatus in accordance with claim 12 and further comprising, a saturating amplifier means driven by said transistor for controlling a normally closed electronic switch for triggering a standard electronic ignition system.

Claim 18

Electromagnetic transducing apparatus in accordance with claim 1 and further comprising, said cam rotatably mounted for presenting edges one at a time adjacent to said line as said cam rotates.

Claim 19

Electromagnetic transducing apparatus comprising, a cylindrical magnetic surrounded about its axis by a coil of wire, substantially planar pole pieces affixed to the ends of said cylindrical magnet and separated by a predetermined spacing corresponding to the separation between adjacent edges of a distributor cam, said distributor cam made of magnetic material for rotation about an axis thereof, said cylindrical magnet being positioned with said pole pieces arranged to simultaneously face consecutive edges of said cam.

Claim 20

Electromagnetic transducing apparatus comprising, a cylindrical magnetic surrounded about its axis by a coil of wire, substantially planar pole pieces affixed to the ends of said cylindrical magnet and separated by a predetermined spacing corresponding to the separation between adjacent edges of a distributor cam, said distributor cam made of magnetic material for rotation about an axis thereof, said cylindrical magnet being positioned with said pole pieces arranged to simultaneously face consecutive edges of said cam.