Fuel control system and method of operating the same

Claim 2

In a fuel control system for a main burner means having a pilot burner means therefor and a thermostatically operated control device for directing fuel from a source thereof to said pilot burner means upon the demand of fuel for said main burner means whereby a safety valve will direct fuel from said source to said main burner means only upon the detection of a certain flame means at said pilot burner means, the improvement wherein electrical ignition means is provided for igniting fuel issuing from said pilot burner means, and a condition responsive device is provided for rendering said ignition means operable when fuel is directed to said pilot burner means upon a demand for fuel for said main burner means by said condition responsive device being responsive to said fuel flow to said pilot burner means and for rendering said ignition means inoperable when said safety valve is directing fuel from said source to said main burner means upon a detection thereby of said certain flame means at said pilot burner means by said condition responsive device being responsive to said fuel flow to said main burner means.

Claim 3

In a fuel control system as set forth in claim 1, said condition responsive device rendering said ignition means so operable and then inoperable each time said fuel is directed to said pilot burner means by said control device upon said demand for fuel for said main burner means.

Claim 4

In a fuel control system as set forth in claim 1, said condition responsive device rendering said ignition means so operable and then inoperable substantially only at the start of a cycle of operation of said main burner means as set by said control device.

Claim 5

In a fuel control system as set forth in claim 1, said pilot burner means being a dual rate pilot burner means whereby said system has means for directing a standby flow of fuel from said source to said pilot burner means to produce a standby flame means at said pilot burner means that is not detected by said safety valve means.

Claim 6

In a fuel control system as set forth in claim 4, said control device having means for terminating said flow of fuel to said pilot burner means when said control device is disposed in an ''''off'''' condition thereof.

Claim 7

In a fuel control system as set forth in claim 1, said condition responsive device comprising a diaphragm operated electrical switch construction for interconnecting an electrical power source to said ignition means when an electrical switch of said construction is closed.

Claim 8

In a fuel control system as set forth in claim 6, said diaphragm switch construction having a single diaphragm operatively controlling said switch, said construction having means for imposing pilot burner means fuel flow pressure on one side of said diaphragm to tend to close said switch and having means for imposing main burner means fuel flow pressure on the other side of said diaphragm to tend to open said switch.

Claim 9

In a fuel control system as set forth in claim 7, said switch construction having biasing means operatively acting on said switch in a direction to normally maintain said switch in an open condition thereof.

Claim 10

In a fuel control system as set forth in claim 6, said diaphragm switch construction having a pair of diaphragms operatively controlling said switch, said construction having means for imposing pilot burner means fuel flow pressure on one side of one of said diaphragm to tend to close said switch and having means for imposing main burner means fuel flow pressure on one side of the other of said diaphragms to tend to open said switch.

Claim 11

In a fuel control system as set forth in claim 9, said diaphragm switch cOnstruction having means for directing source fuel pressure between said diaphragms to respectively act on the other sides thereof to tend to maintain said switch in the open conditions thereof.

Claim 12

In a fuel control system for a main burner means having a pilot burner means therefor and a manually settable thermostatically operated control device for directing fuel from a source thereof to said pilot burner means upon the demand of fuel for said main burner means whereby a safety valve will direct fuel from said source to said main burner means only upon the detection of a certain flame means at said pilot burner means so that said safety valve will be cycled ''''on'''' and ''''off'''' to tend to maintain the output temperature effect of said main burner means at the particular setting of said control device, the improvement wherein an electrical ignition means is provided for igniting fuel issuing from said pilot burner means, and for rendering said ignition means operable substantially only when fuel is initially directed to said pilot burner means upon a demand for fuel for said main burner means caused by an initial setting of said control from an ''''off'''' condition thereof to a desired ''''on'''' condition thereof and for thereafter rendering said ignition means inoperable for that particular setting of said control device when said safety valve is initially directing fuel from said source to said main burner means upon a detection thereby of said certain flame means at said pilot burner means even though said safety valve is subsequently cycled ''''on'''' and ''''off'''' during that particular setting of said control device.

Claim 13

In a fuel control system for a main burner means having a pilot burner means therefor and a manually settable thermostatically operated control device for directing fuel from a source thereof to said pilot burner means upon the demand of fuel for said main burner means whereby a safety valve will direct fuel from said source to said main burner means only upon the detection of a certain flame means at said pilot burner means so that said safety valve will be cycled ''''on'''' and ''''off'''' to tend to maintain the output temperature effect of said main burner means at the particular setting of said control device, the improvement wherein an electrical ignition means is provided for igniting fuel issuing from said pilot burner means, and for rendering said ignition means operable substantially only when fuel is initially directed to said pilot burner means upon a demand for fuel for said main burner means caused by an initial setting of said control from an ''''off'''' condition thereof to a desired ''''on'''' condition thereof and for thereafter rendering said ignition means inoperable for that particular setting of said control device when said safety valve is initially directing fuel from said source to said main burner means upon a detection thereby of said certain flame means at said pilot burner means even though said safety valve is subsequently cycled ''''on'''' and ''''off'''' during that particular setting of said control device.

Claim 14

In a fuel control system as set forth in claim 11, said pilot burner means being a dual rate pilot burner means whereby said system has means for directing a standby flow of fuel from said source to said pilot burner means to produce a standby flame means at said pilot burner means that is not detected by said safety valve means.

Claim 15

In a fuel control system as set forth in claim 12, said control device having means for terminating said flow of fuel to said pilot burner means when said control device is disposed in an ''''off'''' condition thereof.

Claim 16

In a fuel control system as set forth in claim 1, said means for operating said ignition means comprising a diaphragm operated electrical switch construction for interconnecting an electrical power source to said ignition means when an electrical switch of said construction is closed.

Claim 17

In a fuel control system as set forth in claim 14, said diaphragm switch construction having a pair of diaphragms operatively controlling said switch, said construction having means for imposing pilot burner means fuel flow pressure on one side of one of said diaphragms to tend to close said switch and having means for imposing main burner means fuel flow pressure on one side of the other of said diaphragms to tend to open said switch.

Claim 18

In a fuel control system as set forth in claim 15, said diaphragm switch construction having means for directing source fuel pressure between said diaphragms to respectively act on the other sides thereof to tend to maintain said switch in the open condition thereof.

Claim 19

In a method of operating a fuel control system for a main burner means having a pilot burner means therefor and a thermostatically operated control device for directing fuel from a source thereof to said pilot burner means upon the demand of fuel for said main burner means whereby a safety valve will direct fuel from said source to said main burner means only upon the detection of a certain flame means at said pilot burner means, the improvement comprising the steps of providing an electrical ignition means for igniting fuel issuing from said pilot burner means, providing a condition responsive device, rendering said ignition means operable with said condition responsive device when fuel is directed to said pilot burner means upon a demand for fuel for said main burner meAns by causing said condition responsive device to be responsive to said fuel flow to said pilot burner means, and rendering said ignition means inoperable with said condition responsive device when said safety valve is directing fuel from said source to said main burner means upon a detection thereby of said certain flame means at said pilot burner means by causing said condition responsive device to be responsive to said fuel flow to said main burner means.

Claim 20

In a method of operating a fuel control system for a main burner means having a pilot burner means therefor and a thermostatically operated control device for directing fuel from a source thereof to said pilot burner means upon the demand of fuel for said main burner means whereby a safety valve will direct fuel from said source to said main burner means only upon the detection of a certain flame means at said pilot burner means, the improvement comprising the steps of providing an electrical ignition means for igniting fuel issuing from said pilot burner means, providing a condition responsive device, rendering said ignition means operable with said condition responsive device when fuel is directed to said pilot burner means upon a demand for fuel for said main burner meAns by causing said condition responsive device to be responsive to said fuel flow to said pilot burner means, and rendering said ignition means inoperable with said condition responsive device when said safety valve is directing fuel from said source to said main burner means upon a detection thereby of said certain flame means at said pilot burner means by causing said condition responsive device to be responsive to said fuel flow to said main burner means.

Claim 21

In a method as set forth in claim 17, the additional step of causing said condition responsive device to render said ignition means so operable and then inoperable each time said fuel is directed to said pilot burner means by said control device upon said demand for fuel for said main burner means.

Claim 22

In a method as set forth in claim 17, the additional step of causing said condition responsive device to render said ignition means so operable and then inoperable substantially only at the start of a cycle of operation of said main burner means as set by said control device.

Claim 23

In a method as set forth in claim 17, the additional step of forming said pilot burner means from a dual rate pilot burner means, and directing a standby flow of fuel from said source to said pilot burner means to produce a standby flame means at said pilot burner means that is not detected by said safety valve means.

Claim 24

In a method as set forth in claim 20, the additional step of forming said control device with means for terminating said flow of fuel to said pilot burner means when said control device is disposed in an ''''off'''' condition thereof.

Claim 25

In a method as set forth in claim 17, the additional step of forming said condition responsive device from a diaphragm operated electrical switch construction for interconnecting an electrical power source to said ignition means when an electrical switch of said construction is closed.

Claim 26

In a method as set forth in claim 22, the additional steps of forming said diaphragm switch construction with a single diaphragm operatively controlling said switch, imposing pilot burner means fuel flow pressure on one side of said diaphragm to tend to close said switch, and imposing main burner means fuel flow pressure on the other side of said diaphragm to tend to open said switch.

Claim 27

In a method as set forth in claim 23, the additional step of forming said switch construction with biasing means for operatively acting on said switch in a direction to normally maintain said switch in an open condition thereof.

Claim 28

In a method as set forth in claim 22, the additional steps of forming said diaphragm switch construction with a pair of diaphragms operatively controlling said switch, imposing pilot burner means fuel flow pressure on one side of one of said diaphragms to tend to close said switch, and imposing main burner means fuel flow pressure on one side of the other of said diaphragms to tend to open said switch.

Claim 29

In a method as set forth in claim 25, the additional step of directing source fuel pressure between said diaphragms to respectively act on the other sides thereof to tend to maintain said switch in the open condition thereof.

Claim 30

In a method for operating a fuel control system for a main burner means having a pilot burner means therefor and a manuallly settable thermostatically operated control device for directing fuel from a source thereof to said pilot burner means upon the demand of fuel for said main burner means whereby a safety valve will direct fuel from said source to said main burner means only upon the detection of a certain flame means at said pilot burner means so that said safety valve will by cycled ''''on'''' and ''''off'''' to tend to maintain the output temperature effect of said main burner means at the particular setting of said control device, the improvement comprising the steps of providing an electrical ignition means for igniting fuel issuring from said pilot burner means, rendering said ignition means operable substantiallY only when fuel is initially directed to said pilot burner means upon a demand for fuel for said main burner means caused by an initial setting of said control from an ''''off'''' condition thereof to a desired ''''on'''' condition thereof and thereafter rendering said ignition means inoperabale for that particular setting of said control device when said safety valve is initially directing fuel from said source to said main burner means upon a detection thereby of said certain flame means at said pilot burner means even though said safety valve is subsequently cycled ''''on'''' and ''''off'''' during that particular setting of said control device.

Claim 31

In a method for operating a fuel control system for a main burner means having a pilot burner means therefor and a manuallly settable thermostatically operated control device for directing fuel from a source thereof to said pilot burner means upon the demand of fuel for said main burner means whereby a safety valve will direct fuel from said source to said main burner means only upon the detection of a certain flame means at said pilot burner means so that said safety valve will by cycled ''''on'''' and ''''off'''' to tend to maintain the output temperature effect of said main burner means at the particular setting of said control device, the improvement comprising the steps of providing an electrical ignition means for igniting fuel issuring from said pilot burner means, rendering said ignition means operable substantiallY only when fuel is initially directed to said pilot burner means upon a demand for fuel for said main burner means caused by an initial setting of said control from an ''''off'''' condition thereof to a desired ''''on'''' condition thereof and thereafter rendering said ignition means inoperabale for that particular setting of said control device when said safety valve is initially directing fuel from said source to said main burner means upon a detection thereby of said certain flame means at said pilot burner means even though said safety valve is subsequently cycled ''''on'''' and ''''off'''' during that particular setting of said control device.

Claim 32

In a method as set forth in claim 27, the additional steps of forming said pilot burner means from a dual rate pilot burner means, and directing a standby flow of fuel from said source to said pilot burner means to produce a standby flame means at said pilot burner means that is not detected by said safety valve means.

Claim 33

In a method as set forth in claim 28, the additional step of forming said control device with means for terminating said flow of fuel to said pilot burner means when said control device is disposed in an ''''off'''' condition thereof.

Claim 34

In a method as set forth in claim 27, the additional step of providing means for operating said ignition means from a diaphragm operated electrical switch construction for interconnecting an electrical power source to said ignition means when an electrical switch of said construction is closed.

Claim 35

In a fuel control system as set forth in claim 30, the additional steps of forming said diaphragm switch construction with a pair of diaphragms operatively controlling said switch, imposing pilot burner means fuel flow pressure on one side of one of said diaphragms to tend to close said switch, and imposing main burner means fuel flow pressure on one side of the other of said diaphragms to tend to open said switch.

Claim 36

In a method as set forth in claim 31, the additional step of directing source fuel pressure between said diaphragms to respectively act on the other sides thereof to tend to maintain said switch in the open condition thereof.