US3454346A

US3454346A - Ignition means for cooking apparatus and the like

Info

Publication number: US3454346A
Application number: US670307A
Authority: US
Inventors: Francis S Genbauffe
Original assignee: Robertshaw Controls Co
Current assignee: Robertshaw Controls Co
Priority date: 1967-09-25
Filing date: 1967-09-25
Publication date: 1969-07-08
Anticipated expiration: 1986-07-08
Also published as: GB1246327A; FR1585498A; BR6802568D0; NL6813612A

Description

July 8, 1969 F. s. GENBAUFFE 3,454,346

IGNITION MEANS FOR COOKING APPARATUS AND THE LIKE Filed Sept. 25. 1967 if; I I :4 A [6] -71 15 .529" f7 35 //Z1 33 pm fizz I IIII J7 an IIIIIIIIIP 41\\\ 2 6/0 FfiANc lgys g AufFE wk F -2 BY f ms ATTORNEYS United States Patent 3,454,346 IGNITION MEANS FOR COOKING APPARATUS AND THE LIKE Francis S. Genbauife, Irwin, Pa., assignor to Robertshaw Controls Company, Richmond, Va., a corporation of Delaware Filed Sept. 25, 1967, Ser. No. 670,307 Int. Cl. F23q 3/00; F24c 3/10 U.S. Cl. 431266 20 Claims ABSTRACT OF THE DISCLOSURE This disclosure relates to an ignition means for a cooking apparatus or the like which has its pilot burner means for the main burners thereof ignited by electrical sparks created by altering the stresses in a piezoelectric crystal means, the crystal means being so constructed and arranged that each piezoelectric crystal can create ignition sparks of two separate pilot burners. This feature is accomplished by electrically insulating each single crystal means from the cooking apparatus and electrically interconnecting two electrodes to the crystal means with their adjacent electrodes being interconnected to a ground potential whereby two spark gaps are provided for the single crystal means.

This invention relates to improved ignition means for a cooking apparatus or the like as well as to an improved method for igniting burner means of such a cooking apparatus or the like.

It is well known that many cooking apparatus of the fuel burning variety have individual pilot burner means for each main burner thereof whether the main burner is disposed in the oven or on the top of the cooking apparatus, the pilot burners being continuously burning pilot burners and when adversely put out because of air currents or the like, the same must be re-ignited by the housewife or the like utilizing matches and the like.

However, according to the teachings of this invention, ignition means are provided for such pilot burner means wherein the housewife or the like can initiate the actuation of the ignition means completely remote from the pilot burner means while igniting the pilot burner means in a simple and effective manner.

In particular, the ignition means of this invention includes piezoelectric crystal means that when actuated by the housewife or the like will have the stresses therein altered in such a manner that the same will cause sparking at the pilot burner means to ignite the same.

Further, the igniting means of this invention are so constructed and arranged that a single piezoelectric crystal will produce sufficient sparking for igniting more than one pilot burner means.

Accordingly, it is an object of this invention to provide an improved ignition means for a cooking apparatus or the like, the ignition means of this invention having one or more of the novel features set forth above or hereinafter shown or described.

Another object of this invention is to provide an improved piezoelectric igniter arrangement for such a cooking apparatus or the like.

Another object of this invention is to provide an improved method for igniting burner means of a cooking apparatus or the like.

Other objects, uses and advantages of this invention are apparent from a reading of this description which proceeds with reference to the accompanying drawings forming a part thereof and wherein:

FIGURE 1 is a perspective view of a cooking apparatus utilizing the ignition means of this invention.

3,454,346 Patented July 8, 1969 ice FIGURE 2 is a schematic view illustrating the ignition system for the cooking apparatus of FIGURE 1.

While the various features of this invention are hereinafter described and illustrated as being particularly adaptable for providing ignition means for a cooking apparatus, it is to be understood that the various features of this invention can be utilized singly or in any combination thereof to provide ignition means for other apparatus as desired.

Therefore, this invention is not to be limited to only the embodiment illustrated in the drawings, because the drawings are merely utilized to illustrate one of the wide variety of uses of this invention.

Referring now to FIGURE 1, a cooking apparatus is generally indicated by the reference numeral 10* and has an oven chamber 11 provided with a broil burner 12 and a bake burner 13 illustrated in FIGURE 1 in substantially rectangular form while being illustrated in FIGURE 2 as being in tubular form. The oven chamber 11 is opened and closed by a conventional door means 14.

The cooking apparatus 10 includes a plurality of top burner means 15, 16, 17 and 18 with only the top burner means 15 and 16 being illustrated schematically in FIGURE 2.

Individual pilot burner means are provided for the main burners of the cooking apparatus 10 and the broil pilot burner is generally indicated by the reference numeral 19, the bake pilot burner by the reference numeral 20 and the top pilot burners are generally indicated by the

reference numerals

21, 22, 23 and 24 for the respective

top burners

15, 16, 17 and 18. The

pilot burners

19, 20, 21 and 22 are illustrated schematically in FIGURE 2 and are so constructed and arranged that the same are adapted to ignite fuel issuing from the respective main burner means 12, 13, 15 and 16 as long as the respective pilot burners are burning.

However, should one or more of the pilot burners of the cooking apparatus 10 be extinguished for any reason, spark igniting means of this invention is provided for the apparatus 10 and is generally indicated by the reference numeral 25 in FIGURES 1 and 2 and will now be described.

The spark igniting means 25 comprises a support or frame member 26 suitably mounted to the frame structure 27 of the cooking apparatus 10 so that a push rod or manual actuator 28 of the igniter means 25 will be exposed in any suitable location on the apparatus 10, the embodiment of the igniter means 25 illustrated in FIG- URE 1 having the push rod means 28 located on the control panel means 29 of the apparatus 10.

The support frame 26 has one or more piezoelectric crystal elements carried therein between the opposed ends 30 and 31 thereof with such crystal means being disposed in a recess or cutout 32 of the support frame 26. In the embodiment of the igniter means 25 illustrated in FIG- URE 2, two such

piezoelectric crystal elements

33 and 34 are being utilized.

The

crystal elements

33 and 34 are disposed in longitudinal stacked and aligned relation with the element 33 having electrical terminal means 35 and 36 at the opposed ends thereof and the crystal element 34 having electrical terminal means 37 and 38 at the opposed ends thereof. An electrical insulator 39 is disposed between the terminal means 36 and 37 of the

crystal elements

33 and 34 to effectively electrically insulate the

elements

33 and 34 from each other while electrical insulating means 40 and 41 respectively electrically insulate the other ends of the

crystal elements

33 and 34 from the support frame 26 whereby the

crystal elements

33 and 34 are not only electrically insulated from each other, but are also electrically insulated from the support frame 26 and, thus, from the frame means 27 of cooking apparatus 10. If desired, ceramic pressure pads or

elements

42 and 43 can be respectively disposed between the

insulators

40 and 41 and the respective terminal means and 38 as illustrated.

A rocker arm 44 is pivotally or rotatably carried by the support frame 26 and is adapted to rotate relative thereto about a transversely movable axis of rotation generally indicated by the reference numeral 45, the rocker arm 44 carrying a cam member 46 at the rotatably mounted end 47 thereof to be disposed between the insulator and a flat surface 48 of the support frame 26 at the end 30 thereof to also rotate in unison the rocker arm 44 about the movable axis 45. The cam member 46 has a fiat surface 49 cooperating with the fiat surface 48 of the support frame 26 and a true, partial circular surface 50 cooperating with an adjacent fiat surface 51 of the insulator 40 whereby when the cam member 46 is disposed in the position illustrated in FIGURE 2, the

elements

40, 42, 33, 39, 34, 43 and 41 are disposed in stacked relation between the opposed ends 30 and 31 of the support frame 26 and will not alter the stresses in the

crystal elements

33 and 34 to generate a potential difference at the respective terminal means 35, 36 and 37, 38 until the cam element 46 is rotated about the axis to either axially squeeze the

elements

33 and 34 between the opposed ends thereof or relieve such squeezing action.

In particular, when the push rod 28 of FIGURES 1 and 2 is manually or automatically pushed inwardly relative to the apparatus 10, the cam element 46-will rotate about its axis 45 in a clockwise direction so that the corner 52, formed by the juncture of the fiat surface 49 thereof and the circular surface 50 thereof, will bear against the flat surface 48 of the support frame 26 and cause the axis 45 to move downwardly and to the left in FIGURE 2 to increase the effective length of the cam member 46 between the surface 48 of the support frame 26 and the surface 51 of the insulator 40 to impose a substantially longitudinal compressive and squeezing action on the

elements

33 and 34 between the ends 30 and 31 of the support frame 26 so that the stresses in the

crystals

33 and 34 are sufficiently altered to cause the same to create a potential difference at the respective pairs of

terminals

35, 36 and 37, 38 to be utilized in a manner hereinafter described. When such compression or squeezing action on the crystal means 33 and 34 are subsequently relieved by the operator manually or automatically releasing the inwardly imposed push force on the push rod 28, the cam member 46 will rock back to the position illustrated in FIGURE 2 to effectively decrease the effective cam length of the cam member 46 between the surfaces 48 and 51 to thereby again alter the stresses in the

crystal elements

33 and 34 as the same longitudinally expand from their previous squeezed condition to also generate a potential difference at the respective pairs of

terminals

35, 36 and 37, 38.

During such rotation of the cam element 46, the stack of

elements

40, 42, 33, 39, 34, 43 and 41 tends to rock as a unit to the left as the cam element 46 is rotated in a clockwise direction and tends to rock to the right when the cam element 46 is rotated in a counterclockwise direction back to the position illustrated in FIGURE 2 whereby the insulator 41 can be provided with an arcuate surface 53 that bears against a flat surface 54 of the support frame 26 to permit such rocking of the stack of elements between the opposed ends 30 and 31 of the support frame 26.

A first pair of

electrodes

55 and 56 are mounted to the frame means 27 of the apparatus 10 adjacent the

respective pilot burners

21 and 22 and in spaced relation from the

pilot burners

21 and 22 so as to define

spark gaps

57 and 58 adjacent the fuel outlet means 59 and 60 of the

pilot burners

21 and 22. The

electrodes

55 and 56 are electrically insulated from the frame means 27 of the apparatus 10 and are electrically interconnected to the

terminals

36 and 35 by suitable leads 61 and 62.

Similarly, another pair of

electrodes

63 and 64 are carried by the apparatus 10 and are disposed in spaced relation from the

pilot burners

19 and 20 to define

spark gaps

65 and 66 adjacent the fuel outlet ends 67 and 68 of the respective pilot burner means 19 and 20. The

electrodes

63 and 64 are also electrically insulated from the frame-means 27 of the apparatus 10 and are respectively lnterconnected to the terminal means 38 and 37 by leads 69 and 70.

The pilot burner means 21, 22, 19 and 20 are electrically conductive and are, in effect, connected to a ground potential by being electrically interconnected to the frame means 27 of the apparatus 10 and such ground potential of the pilot burners is generally indicated by the

reference numerals

71 and 72 in FIGURE 2, the frame means 27 of the apparatus 10 being effectively grounded through interconnection thereof to the gas supply lines and the like and also by conventional grounding means.

In this manner, it can be seen that the pilot burner means 21 and 22 respectively provide ground electrodes cooperating with the

electrodes

55 and 56 to define the

spark gaps

57 and 58. Similarly, the

pilot burners

19 and 20 provide ground electrodes for cooperating with the

electrodes

63 and 64 to provide the

spark gaps

65 and 66.

The operation of the igniting means 25 for the apparatus 10 will now be described.

When the housewife or the like notices that one of the burner means 12, 13, 15, 16, 17 or 18 does not ignite when she turns on one of the main selector knobs 73 on the control panel 29 of the apparatus 10, or when she actually notices that one of the pilot burner means 19, 20, 21, 22, 23 and 24 are not burning, she can merely push inwardly on the push rod 28 to effect rocking of the cam member 46 of the igniter means 25 whereby the stresses in each

crystal element

33 and 34 will be altered in the mannerpreviously described so that one potential will be created at the

electrodes

55 and 63 and an equal and opposite potential will be created at the

el ctrodes

56 and 64. When the differences in potential between the

electrodes

55, 56, 63 and 64 and their resp ctive grounded

electrodes

21, 22, 19 and 20 reaches a particular magnitude, electrical arcing will be created across the

spark gaps

57, 58, 65 and 66 in substantially a simultaneous manner whereby such electrical sparking will ignite the fuel issuing from any unlit pilotburner means 21, 22, 19 or 20.

Continued inward movement of the push rod 28 to effect a squeezing action on the

elements

33 and 34 will produce the above-described sparking one or more times depending upon the length of inward movement of the push rod 28. Also, releasing of the rod 28 will also alter the stresses in the

crystals

33 and 34 to effect sparking at

thte spark gaps

57, 58, 65 and 66 on the return of the push rod 28 to its full out position as illustrated in FIG- URES l and 2.

While it is believed that merely one actuation of the push rod 28 will effectively light any unlit pilot burner means 1922, a mere repetitive pushing action of the housewife or the like on the push rod 28 will more than assure that any unlit pilot burner means 19-22 will be effectively lit by the sparking created by the

crystal means

33 and 34.

Therefore, it can be seen that by arranging the

crystal means

33 and 34 in the manner previously described, each crystal means 33 or 34 is adapted to effectively ignite two or more pilot burner means so that a relatively inexpensive ignition means can be provided for the apparatus 10.

While the igniter means 25 illustrated in FIGURE 2 has the crystal element 34 being utilized to ignite the oven pilot burner means 19 and 20 and the crystal element 33 to ignite only the pilot burner means 21 and 22 of the top burner means 15 and 16, it is to be understood that a third crystal element can be disposed in a stacked relation in a manner similar to that illustrated in the drawings to effect sparking at the pilot burner means 23 and 24 of the other top burners 17 and 18.

However, it is also to be realized that the pilot burner means 21 and 22 illustrated in FIGURE 2 could be utilized as the only top pilot burner means for the apparatus and the same could be utilized in combination with flash tubes so that the pilot burner means 21 can effectively ignite the two top burner means and 16 and the pilot burner means 22, through another flash tube arrangement, can be utilized to ignite the other two burner means 17 and 18 in a manner well known in the art. Thus, it is believed that only two piezoelectric crystals are necessary for effectively igniting all of the required number of pilot burner means for a cooking apparatus of the type similar to the apparatus 10 illustrated in FIGURE 1.

Also, While this igniter means of this invention has been described as igniting pilot burner means for the cooking apparatus, it is to be understood that such igniter means can be utilized to directly ignite the main burner means of the cooking apparatus or the like without utilizing pilot burners therefor.

While the form of the invention now preferred has been disclosed as required by the statutes, other forms may be used, all coming within the scope of the claims which follow.

'What is claimed is:

1. In combination, frame means, a pair of first electrodes carried by said frame means, said first electrodes each being electrically connected to a ground potential, a. piezoelectric crystal, means supporting said crystal to said frame means, said supporting means electrically insulating said crystal from said frame means and from ground potential, a pair of second electrodes carried by said frame means and respectively being adjacent said first electrodes to define two spark gaps, means electrically insulating said second electrodes from said frame means and from ground potential, means electrically interconnecting said crystal to said second electrodes, and means for selectively causing said crystal to create potentials respectively at said second electrodes that will cause substantially simultaneous sparking across both of said spark gaps between said first and second electrodes.

2. A combination as set forth in claim 1 wherein said frame means is grounded and wherein said first electrodes are each electrically connected to said frame means to "be at said ground potential.

3. A combination as set forth in claim 1 and including a pair of pilot burner means carried by said frame means to be respectively ignited by said sparks at said spark gaps.

4. A combination as set forth in claim 3 wherein each pilot burner comprises one of said electrodes.

5. A combination as set forth in claim 4 wherein each pilot burner comprises one of said first electrodes.

6. A combination as set forth in claim 1 and including a second piezoelectric crystal electrically insulated from said frame means and ground potential while being supported by said frame means, a third pair of electrodes each being electrically connected to a ground potential, and a fourth pair of electrodes carried by said frame means and respectively being adjacent said third electrodes to define two other spark gaps, means electrically insulating said fourth electrodes from said frame means and from ground potential, means electrically interconnecting said second crystal to said fourth electrodes, and means for causing said second crystal to create potentials respectively at said fourth electrodes that will cause substantially simultaneous sparking across both of said other spark gaps between said third and fourth electrodes.

7. In combination, frame means, a pair of first electrodes carried by said frame means, said first electrodes each being electrically connected to a ground potential, a piezoelectric crystal, means supporting said crystal to said frame means, said supporting means electrically insulating said crystal from said frame means, a pair of second electrodes carried by said frame means and respectively being adjacent said first electrodes to define two spark gaps, means electrically insulating said second electrodes from said frame means, means electrically interconnecting said crystal to said second electrodes, means for selectively causing said crystal to create a potential at said second electrodes that will cause sparking across said spark gaps between said first and second electrodes, a second piezoelectric crystal electrically insulated from and supported by said frame means, a third pair of el ctrodes each being electrically connected to a ground potential, -a fourth pair of electrodes carried by said frame means and respectively being adjacent said third electrodes to define two other spark gaps, means electrically insulating said fourth electrodes from said frame means, means electrically interconnecting said second crystal to said fourth electrodes, and means for causing said second crystal to create a potential at said fourth electrodes that will cause sparking across said other spark gaps between said third and fourth electrodes, said means for causing said first-named crystal to create said potential and said means for causing said second crystal to create said potential being the same means whereby said sparks are created substantially in unison.

8. A combination as set forth in claim 7 wherein said first-named crystal and said second crystal are supported in stacked relation.

9. A combination as set forth in claim 8 and including electrical insulating means disposed between said crystals.

10. A combination as set forth in claim 6 and including four pilot burner means carried by said frame means to 'be respectively ignited by said sparks at said four spark gaps.

11. A sparking apparatus comprising a support frame, a piezoelectric crystal carried by said support frame, electrical insulation means carried by said support frame and electrically insulating said crystal from said frame and from ground potential, a pair of terminal means respectively interconnected to said crystal, and means carried by said support frame to alter the stresses in said crystal to cause a difierence in potential at said terminal means so that each terminal means has a potential differential relative to a ground potential to cause sparking across a spark gap separate from the spark gap for the other terminal while sparking substantially simultaneously therewith.

12. A sparking apparatus as set forth in claim 11 and including a second piezoelectric crystal carried by said support frame, said electrical insulation means electrically insulating said crystal from said frame and from ground potential, and a pair of second terminal means respectively interconnected to said second crystal to cause a potential difference at said second terminal when the stresses in said second crystal are altered so that each second terminal means has a potential differential relative to a ground potential.

13. A sparking apparatus as set forth in claim 12 wherein said means to alter the stresses in said first-named crystal also alters the stresses in said second crystal in substantial unison therewith.

14. A sparking apparatus as set forth in claim 12 wherein said crystals are disposed in stacked relation.

15. A sparking apparatus comprising a support frame, a piezoelectric crystal carried by said support frame, electrical insulation means carried by said support frame and electrically insulating said crystal from said frame, a pair of terminal means respectively interconnected to said crystal, means carried by said support frame to alter the stresses in said crystal to cause a difference in potential at said terminal means, a second piezoelectric crystal carried by said support frame, said electrical insulation means electrically insulating said crystal from said frame, and a pair of second terminal means respectively interconnected to said second crystal to cause a potential difference at said second terminal when the stresses in said second crystal are altered, said crystals being disposed in stacked relation, said electrical insulation means electrically insulating said crystals from each other.

16. A method for producing two ignition sparks from a single piezoelectric crystal comprising the steps of electrically insulating said crystal from a frame means and from ground potential, electrically interconnecting said crystal to a pair of first electrodes, electrically insulating said first electrodes from said frame means and from ground potential, electrically interconnecting a pair of second electrodes to a ground potential, disposing said second electrodes on said frame means so each second I means comprises the steps of disposing two burner means electrode is adjacent a first electrode to define a spark gap therewith, and causing said crystal to create potentials 17. A method as set forth in claim 16 wherein said step of electrically interconnecting said second electrodes to a ground potential includes the step of electrically-in terconnecting said second electrodes to said frame means.-

18. A method as set forth in claim 16 and including the step of disposing two burner means on said frame means to respectively be ignited by said sparking at said spark 19. A method for producing two ignition sparks from a single piezoelectric crystal comprising the steps of electrically insulating said crystal from a frame means, electrically interconnecting said crystal to a pair of first electrodes, electrically insulating said first electrodes from on said frame means to respectively beignited by said sparking at said spark gaps, and utilizing said burner means as said second electrodes. p

20. A method as set forthin claim 16 and including the step of producing two "other ignition sparks from a second ,crystal in the same manner as by said first-named crystal by the step of causing said first-named sparking.

References Cited UNITED STATES PATENTS FREDERICK L. MATTESON; 1R1, Primary Examiner.

EDWARD G. FAVORS, Assistant Examiner.