Gas igniter system

Claim 2

A transformerless igniter system adapted to be energized from a pair of AC supply leads and to ignite gas at a burner, said system comprising: means, including at least one electrode, for defining a spark gap adjacent said burner; a spark coil having a primary winding and a secondary winding; means for connecting one side of said secondary winding to said one electrode; means, including a coupling capacitor, for connecting the other side of said secondary winding to the side of said spark gap which is opposite said one electrode; a timing capacitor; first circuit means, including a relatively high value timing resistance, for applying a charging current to said timing capacitor from said AC supply leads; second circuit means, including a relatively high value isolating resistance, for connecting said other side of said secondary winding to said timing capacitor; a triggerable semiconductor current-switching device connected to apply an electric pulse to said primary winding; and means for triggering said switching device when the voltage on said timing capacitor exceeds a predetermined level to generate a spark at said gap, whereby a flame at said burner shunts said timing capacitor through said isolating resistance and prevents the voltage on said timing capacitor from reaching said predetermined level thereby inhibiting sparking and whereby said isolating resistance isolates said spark gap means from the AC supply leads.

Claim 3

An igniter system as set forth in claim 1 wherein said burner defines the side of said spark gap opposite said electrode.

Claim 4

An igniter system as set forth in claim 1 wherein said triggerable switching device comprises an SCR.

Claim 5

An igniter system as set forth in claim 3 including an energy storage capacitor which is discharged by said SCR into the primary winding of said spark coil to generate a spark at said gap.

Claim 6

An igniter system as set forth in claim 4 wherein said first circuit means which applied a charging current to said timing capacitor is connected to said energy storage capacitor whereby said timing capacitor charges more slowly than said energy storage capacitor.

Claim 7

An igniter system as set forth in claim 1 including a voltage divider comprising a pair of resistors for obtaining an intermediate voltage from AC voltages of opposite polarity applied to said supply leads.

Claim 8

An igniter system as set forth in claim 6 wherein said intermediate voltage is substantially equal to ground potential.

Claim 9

An igniter system as set forth in claim 1 wherein sAid means for triggering said switching device comprises a neon lamp.

Claim 10

A transformerless igniter system adapted to be energized from a pair of AC supply leads and to ignite gas at at burner, said system comprising: an electrode, adapted to be mounted adjacent said burner for defining a spark gap therewith; a spark coil having a primary winding and a secondary winding, one side of said secondary winding being connected to said electrode; a coupling capacitor for connecting the other side of said secondary winding to said burner; an energy storage capacitor; means, including a rectifier, for charging said energy storage capacitor from said supply leads; a timing capacitor; first circuit means, including a relatively high value timing resistance, for applying a charging current to said timing capacitor from said storage capacitor; second circuit means, including a relatively high value isolating resistance, for connecting said other side of said secondary winding to said timing capacitor; an SCR connected to discharge said energy storage capacitor through said primary winding; and a neon lamp connected between said timing capacitor and the gate of said SCR for triggering said SCR when the voltage on said timing capacitor exceeds a predetermined level thereby to generate a spark at said gap, whereby a flame at said burner shunts said timing capacitor through said isolating resistance and prevents the voltage on said timing capacitor from reaching said predetermined level thereby inhibiting sparking and whereby said isolating resistance isolates said electrode from the AC supply leads.

Claim 11

A transformerless igniter system adapted to be energized from a pair of AC supply leads and to ignite gas at at burner, said system comprising: an electrode, adapted to be mounted adjacent said burner for defining a spark gap therewith; a spark coil having a primary winding and a secondary winding, one side of said secondary winding being connected to said electrode; a coupling capacitor for connecting the other side of said secondary winding to said burner; an energy storage capacitor; means, including a rectifier, for charging said energy storage capacitor from said supply leads; a timing capacitor; first circuit means, including a relatively high value timing resistance, for applying a charging current to said timing capacitor from said storage capacitor; second circuit means, including a relatively high value isolating resistance, for connecting said other side of said secondary winding to said timing capacitor; an SCR connected to discharge said energy storage capacitor through said primary winding; and a neon lamp connected between said timing capacitor and the gate of said SCR for triggering said SCR when the voltage on said timing capacitor exceeds a predetermined level thereby to generate a spark at said gap, whereby a flame at said burner shunts said timing capacitor through said isolating resistance and prevents the voltage on said timing capacitor from reaching said predetermined level thereby inhibiting sparking and whereby said isolating resistance isolates said electrode from the AC supply leads.

Claim 12

A transformerless igniter system adapted to be energized from a pair of AC supply leads and to ignite gas at a burner, said system comprising: means, including at least one electrode, for defining a spark gap adjacent said burner; a spark coil having a primary winding and a secondary winding; means for connecting one side of said secondary winding to said one electrode; a timing capacitor; first circuit means, including a relatively high value timing resistance, for applying a charging current to said timing capacitor from said AC supply leads; second circuit means, including a relatively high value isolating resistance, for connecting said other side of said secondary winding to said timing capacitor; a triggerable semiconductor current-switching device connected to apply an electric pulse to said primary winding; means for triggering said switching device when the voltage on said timing capacitor exceeds a predetermined level thereby to generate a sparking pulse; and discriminating means presenting an essentially open circuit to said charging current and being conductive of said sparking pulse for connecting the other side of said secondary winding to the side of said spark gap which is opposite said one electrode, whereby a flame at said burner shunts said timing capacitor through said isolating resistance and prevents the voltage on said timing capacitor from reaching said predetermined level thereby inhibiting sparking and whereby said isolating resistance isolates said spark gap means from the AC supply leads.

Claim 13

A transformerless igniter system adapted to be energized from a pair of AC supply leads and to ignite gas at a burner, said system comprising: means, including at least one electrode, for defining a spark gap adjacent said burner; a spark coil having a primary winding and a secondary winding; means for connecting one side of said secondary winding to said one electrode; a timing capacitor; first circuit means, including a relatively high value timing resistance, for applying a charging current to said timing capacitor from said AC supply leads; second circuit means, including a relatively high value isolating resistance, for connecting said other side of said secondary winding to said timing capacitor; a triggerable semiconductor current-switching device connected to apply an electric pulse to said primary winding; means for triggering said switching device when the voltage on said timing capacitor exceeds a predetermined level thereby to generate a sparking pulse; and discriminating means presenting an essentially open circuit to said charging current and being conductive of said sparking pulse for connecting the other side of said secondary winding to the side of said spark gap which is opposite said one electrode, whereby a flame at said burner shunts said timing capacitor through said isolating resistance and prevents the voltage on said timing capacitor from reaching said predetermined level thereby inhibiting sparking and whereby said isolating resistance isolates said spark gap means from the AC supply leads.

Claim 14

An igniter system as set forth in claim 10 wherein said discriminating means is a capacitor.

Claim 15

An igniter system as set forth in claim 10 wherein said discriminating means is a voltage breakdown device.

Claim 16

An igniter system as set forth in claim 12 wherein said breakdown device is a neon tube.

Claim 17

An igniter system as set forth in claim 12 wherein said breakdown device is a second spark gap.