US2384797A - Gas igniter - Google Patents

Description

Pmied sept. is, 1945 Joseph A. Cerny, University Heights, and Julius Converse, East Cleveland, Ohio, assignors to The Bryant Heater Company, Cleveland, Ohio,

a corporation o! Ohio Application June 17, 1941, Serial No. 398,434

2 Claims.

This invention relates to improvements ingas igniters, and has reference particularly to the mounting of anigniter oi the heating coil type, and to means for assuring the presentation thereto of a highly combustible gas and air mixture.

.One of the objects of the invention is the provision of improved means for mounting oi.' the coil in its insulation block which at the same time shall provide improved electrical connections with the lead wires.

Another object is the provision of improved means for mounting the insulation block.

' A further object is the provision oi' improved means for causing deceleration and turbulence oi' the combustible gas stream. and its mixture with additional air Just prior to contacting the heating coll.

' Other objects and features oi' novelty will appear as we proceed with' the description of those embodiments of the invention which, for the purposes oi' the present application, .we have illustrated in the accompanying drawing, in which Fig. 1 is a plan view partially in section and on an enlarged scale of a coil block with coil and lead wires assembled therein in accordance with the invention.

Fig. 2 is an end view of the same.

Figs. 3 and 4 are front and rear views respectively.

Fig. 5 is a fragmental elevational view showing 30 means for mounting the coil on an upright pilot tube.

Fig. 6 is an elevational view of the same at right angles to that of Fig. 5.

' Fig. 7 is a cross-sectional view taken substanf 35 tially on the line 'l-'lv oi' Fig. 5.

Fig. 8 is a plan view of a modified form oi' mounting suitable fora horizontally extending pilot tube. ,/-'f'-" Fig. 9 is a crossjsectionalrvi'e'v taken substanti- 40 ally on the linets of Fig. 8.

Figf'lO is a fragmental plan view of another type oi mounting suitable for horizontally ar ranged pilot tubes.

Fig. v11 is a side elevational and Fig. 12 is a cross-sectional view taken substan-L tially on the line I2i2 of Fig. 10.

In the drawing the coil block is illustrated at I0.

It is formed of suitable heat resistant electrical insulation.' for example, porcelain or lava. The iront side of the block is provided with a pair oi' longitudinally extending wings Il, Il forming a channel therebetween. The ends of these wings stop somewhat short of the ends of the block view oi'ithe same, 45

(Cl. 21B-32) 4 proper, as clearly illustrated in Figs. 1 and 3. An

electric heating coil I2 ispositioned within this channel, the two end wires I8 and I4 of the4 coil projecting through small passages Il and It in the block, whichv passages communicate respectively with cavities Il and il each of which is open through at least one wall of the block inorder that the cavities may be'accessible from the exterior of the block. As shown'herein the cavity I1 is open through the rear walland the bottom wall of the block, while the cavity il is open throughthe rear wall and top wall of the block.

'Ihe block is also provided with longitudinal passages I9 and 200i' larger bore than the' passages IS and I6, for the reception oi lead wires 2| and 22. These wires project through the passages into the cavities il and I8, thereby intersecting the coil end wires I3 and il. Each pair of intersecting wires isjoined mechanically and electrically in some suitable manner, preferably by means of a high temperature solder, the soldered Joints being illustrated in the drawing at 23 and 'respectively. A braaed connection and a welded connectionare obviously mechanical equivalents.

of the soldered Joint an'dshould be understood as comprehended by the term`l soldered joint. 'I'he cavities are oi' such size that a soldering tool of appropriate dimensions may be readily inserted, and when the joint is made, whether soldered or otherwise, a good mechanical connection as well as a good electrical connection is accomplished and the wiresare firmly held in the block', and each one locks the other in place.

Referringvto Figs. 5, 6 and 7, the coil block'ls shown mounted upon an upright pilot `tube 2l having a lower port v26, upper ports 21 and a series oi' intermediate ports 28 for ytransmitting ilame from the lannion." to the upper ports 21. A

v'lraliet'il having a shelf member 30 is fastened to the tube 2l by a screw Il or the like in such position that the shell' I0 stands adjacent to and beneath the port 28. I'he block il is mounted upon this shelf member by meansl of a screw 32 which extends through a smooth cylindrical hole 33 in the block into a threaded hole in the bracket.

A mixtureot combustible gas and air, hereinafter calledgas, when discharged 'from port 28,`

flows over shelf 30 and up against an end wall of the block I0. which then constitutes a target for the gas stream. Upon striking the target the gas rebounds. is deilected and rolls sidewise in both directions as well as upward, setting up low turbulence and eilecting a'mlxture with additional air. 'I'he term target as hereinafter employed should be understood as applyim only to an element having the functions lust described, and as excluding a mere gas deilector. The shelf or guard plate I prevents air currents from disturbing the gas stream. A small portion of this mix ture after moving sidewise enters the adjacent end of the coil I2 and envelope its exterior so that ignition of the lean mixture takes place readily when the coil attains combustion temperature.

Referring to Figs. 8 and 9, $5 is a horizontal pilot tube having a port 3U. I1 is a relatively nxed element upon which the lighter coil and associated parts are carried. AA sheet metal stamping comprising portions I8 and 3l at right angles to each other extends beneath the ilxed element $1 and has an upwardly extending rear flange 40 engaging one edge of the element 31. The front side 39 of this stamping is cut away to receive the two wings Il of the block and the space therebetween in which the coil l2 is located. A bottom portion 4| oi' the stamping extends forwardly beneath the coil and beneath the port 38 of the pilot tube. This stamping and the block l0 are held in place by a bolt 42 and nut 43, the bolt extending through a hole in part 31, through' a slot 44 in part 3l of the stamping and through the hole I3 in the block. The part 31 is broken away in Fig. 8 of the drawing in order to more clearly illustrate the stamping. It will be observed that by making the cuteaway portion of the front wall 39 iit closely around the wings Il the block and stamping are interconnected so that relative displacement is impossible so long as the bolt 42 and its nut 43 remain in position.

In this lform of the invention the front wall 3! of the stamping opposite to the port 36 constitutes the target for the gas stream. Some of the gas may strike the bottom portion 4I of the stamping before it encounters the target proper, but the effect is quite similar to that obtaining with the use of the construction Yshown in Figs. 5, 6 and '7; that is to say, the gas after it strikes the wall 39 is deflected, becomes mixed with air, and rolls in opposite directions from the target, part of it entering the coll I2. The bottom portion 4l of the stamping in this case functions partly as a guard plate or shelf for preventing currents of air from interfering with the ow of the gas stream and partly as a deflector for directing the oblique gas stream against the target.

In Figs. 10, 1l and 12 a horizontal pilot tube 45 lies directly adjacent a supporting element 46 upon which the block I0 is mounted by means of a screw 32. In this modification the target is constituted by a flange 41 extending upwardly from a sheet metal element 48 which runs beneath the supporting element 46 and is secured thereto by a screw 49. This sheet metal element may have a reenforcing flange and may have further an integral cap member 5| for closing the end of the pilot tube 45. In the tube there is a port 52 pslticnedgopposlte the target 41. Here the flat upper surfacemfithe supporting element 48 constitutes the guard plateorishelf and the gas stream flows above it toward the target, then breaking up, mixing with air, and a portion entering the end of the heatingv coil I2.

While in all of the coil mountings herein illustrated the guard plate is shown as a at hori- 7 zontal shelf, it is not essential thatit be ilat or horizontal and, in fact, we have found that a vertical plate functions quite satisfactorily in some instances. It should, however, be close enough to the gas stream to guard the stream in order that the latter may flow undisturbed. During this flow the stream expands and decelerates and picks up air. The presence of the guard permits the use of a relatively long gas stream which of course increases the opportunity for expansion and deceleration. When the decelerated stream strikes the target it is dei'iecied in all directions and may be said to roll into a cloud oi' low turbulence which moves radially outward at a relatively slow rate of speed, picking up additional air in the process, so that the mixture becomes leaner and leaner as it progresses outward from the point of impact upon the target. An almost quiescent condition of the correct mixture at the point of ignition is desirable. It is not well to so restrict the pilot port that the latter can easily clog. rIlherefore, since a stream of substantial size must be employed, a remote target location is desirable. The more remote this location, the more necessary becomes the guard. The igniting coil is arranged preferably with its axis in a generally radial direction with respect to this point, with the result that at some part of is lengh an ideal mixture, that is one capable of substantially complete combustion, is contacted. The ignition of the mixture is certain to occur at this point at least. The rate of flow at the coil is also low so that the cooling effect due to flow is minimized.

Gas in different localities differs considerably in its composition, so that the point of substantially perfect combustion mixture may be at one radial distance from the center of the cloud for one locality and at an entirely diierent distance for another locality, but by arranging the coil with its axis in a generally radial direction the apparatus automatically compensates for such diilferent gases and functions properly in a wide to variety of cases without any shifting of coil position.

Having thus described our invention, we claim:

1. In a gas igniter, a heat resistant block of electrical insulation, an electric igniter coil 45 mounted thereon, said block having a passage therethrough into which one end of said coil projects and having a second passage substantially intersecting said first passage, a lead wire 50 in said second passage, said block having an open cavity at the intersection of said passages providing access for a soldering tool, the crossed wires extending adjacent a wall of said cavity, whereby the said wall forms a back stop for the wires when the tool is pressed against them to 55 eiIect a soldered joint.

2. In a gas igniter, a heat resistant block of electrical insulation, an electric igniter coil carried upon the face of the block with straight wires at its ends projecting into the block through 60 passages provided therein, by which the wires are located, said block having other passages spaced apart in a plane parallel to the face of the block, an electric conductor having lead wires straight end portions of which extend 05 through and are located by said 1mi-named pas- Visages, said block having open cavities extending thiieinto from the back of the block and from the opposite sides thereof, each coil end wire meeting one lead wire in one of said cavities, and 0 a soldered joint between each coil end and the corresponding lead wire in each of said cavities.

JOSEPH A. CERNY. JULIUS CONVERSE.

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