US2053423A - Vertical type boiler heater - Google Patents

Description

Sept. 8, 1936. o. A. COLBY VERTICAL TYPE BOILER HEATER Filed June 14, 1934 2 Sheets-Sheet l INVENTOR Ora Y0/g WITNESSES ATTRNEY Slept 8, 1936- Io. A. COLBY 2,053,423

VERTICAL TYEE BOILER HEATER Filed June 14, 1934 2 Sheets-Sheet 2 @i ,ww

INVTETX Ora Oibg.

` ATTRNEY Patented Sept. 8, 1936 UNITED STATES PATENT OFFICE VERTICAL TYPE BDILER HEATER Sylvania Application June 14, 1934, Serial No. 730,580

8 Claims.

My invention relates to water heaters and particularly to heating units for steam boilers.

An object of my invention is to provide a relatively simple and easily manufactured and assembled heating unit, having rugged parts which will withstand high temperatures and which will hold the resistor member out of contact with the surrounding metal parts, thereby permitting of energizing the resistor at relatively high voltage.

Another object of my invention is to provide a heating element which can be removed and replaced without the necessity of cooling down the steam generator in which it is located.

, Another object of my invention is to provide l a high capacity electric heating unit having maximum heat concentration, located in a nre tube of a steam boiler and having both terminals of the resistor located at one end thereof.

Another object of my invention is to provide 20 a heating unit having a cushioned mounting as a part of the unit.

Other objects of my invention will either be apparent from a description of a preferred embodiment of the device embodying my invention 25 or will be pointed out specifically hereinafter.

In practicing my invention I provide a boiler caslnghaving a plurality of fire tubes extending therethrough, the ends of which are secured to opposite walls of the boiler casing, together with heating units located in the respective tubes. Each heating unit includes a plurality of sets of helically wound turns of resistor wire connected by axial portions, pairs of externally grooved elongated refractory resistor supports, a metal rod extending between the externally grooved refractory supports, electric insulating washers between axially adjacent pairs of refractory supports, the metal rod holding the refractory resistor supports in proper operative positions within the helically wound turns and having its inner end electrically connected to the inner end of the relatively heavy resistor wire to constitute a terminal therefor.

In the drawings,

Figure 1 is a top plan view of a steam boiler embodying my invention,

Fig. 2 is a view in side elevation thereof with a part broken away to show the internal ccn- 50 struction thereof,

, Fig. 3 is a View in longitudinal section through a heating unit embodying my invention shown as being located in a fire tube,

Fig. 4 is a plan view of the structure shown 55 in Fig. 3',

(Cl. 21S-38) Fig. 5 is a view in lateral section taken on the line V-V of Fig. 3,

Fig. 6 is a view in side elevation of a refractory resistor supporting member,

Fig. 7 is a plan view of the device shown in 5 Fig. 6,

Fig. 8 is a View in side elevation of apart of the refractory resistor support shown in Fig. 6 and taken at right angles thereto.

Fig. 9 is a fragmentary View in longitudinal 10 section on the line IX-IX of Fig. 6 and Fig. 10 is a fragmentary view through a part of the resistor support shown in Fig. 6 and taken on the line X-X thereof.

A boiler shell indicated generally by the numeral Il in Fig. 2 of the drawings may be of circular shape and have a lower head I3, an upper head l5, together with any desired number of iire tubes Il which are secured to the upper and lower casing walls in a manner well known in the art to provide a water-tight boiler structure.

A bottom plate i9 may be provided in order to properly support the boiler and a top plate 2l is also provided which is secured to an annular ring 23 by a plurality of bolts 25. On the inside 25 of the top cover 2l, I provide a plate 21 of electric-insulating material not only to retain as much heat as possible within the boiler or rather to prevent it being conducted upwardly to the plate or cover 2l, but also for another purpose 30 to be'hereinafter referred to. I provide a water inlet connection 29 and a steam outlet 3| in a manner well known in the art. I provide also a heat insulation 33 around the shell I I and protect the same by an insulation jacket 35 of sheet metal. While I have illustrated and described specific forms of water inlet and steam outlets, I do not desire to be limited thereto and it is to be noted that other details or adjuncts of a steam boiler may be provided but since these constitute no part of my present invention, I have not illustrated or described the same.

Within each of the plurality of re tubes Il, I locate a quickly removable electric heating unit which includes a resistor element 31. As my invention has particular reference to steam boilers of rather large steam generating capacity, I prefer to make the resistor element 3l of a relatively heavy resistor wire and pre-form the same to comprise a plurality of sets of helical turns 5 located in spaced relation relatively to each other as is shown more particularly in Fig. 3 of the drawings, adjacent sets or groups of helically wound turns being connected by substantially axially extending integral portions 39.

In order'to maintain the sets of helically wound turns of the resistor 3l in proper relative operative positions, I provide a plurality of elongated, eXternally-grooved refractory resistor supports individually designated by lil.. These refractory resistor supports have outer arcuate surfaces 33V 'and inner arcuate surfaces 55, both of these exwhich, as may be seen more particularly byY reference to Fig. 6 of the drawings, are spaced apartaxially from each other and extend generallyspeaking helically along the outer surface of member lli. The effect ofthe lugs fil, which may be connected by ridges i9 is to provide helical grooves Vas shown at 5i in Figs.V 8 and 9 of the drawings, which grooves extend partially only,

' Y peripherally of members il and are adapted to receive a corresponding part ofthe respective turns of Yresistor 3l., While I have shown tWo cooperating-supports lll, VI do not desire to be limited thereto as I may use three such supportsVV Without departingV from th'e'scope of my invention. Y

The particular shape ofthe refractory resistor 'Y support il has been selected with a view of being able to axially and quickly assemble the entireV heating unit and it is to be noted that resistor member '3l' is pre-formed to comprise the pluralityof sets of Vadjacent helical turns spaced apart by integral axially extending portions 39. The pairs-of supports il Yare introduced into the helically wound resistor member first in a substantially axial direction, one refractory memberat-a time and temporarily held in such positions that they will beradially spaced from each other withV -the resistor 3l or parts of Veach turn thereof in the partial grooves 5l. 'A plurality of electric-insulating spacers 53 are then introduced in a generally' lateral direction so that a recess 55 in the periphery thereof will engage with or receive the respective axial portions 39 of the resistor or in the case of the end spacers or washers, they will receive end portions 5l at theY inner end of the tube and an end portion 59 at the outer end of the tube.

I then introduce a metal rod 6l in a generally axial direction, the diameter of the rod 6l being such that `it will engage the inner arcuate surfacesV l5 of the two co-extensive refractory resistor supports, the relative positions of the three parts being shown particularly in Fig. 5 of the drawings. These refractory supports will, therefore, act to properly hold and space' the helical turns of the resistor.

A spacing Washer 53 is mounted on the inner endv of rod El and has auxiliary washers E5 located one at each side thereof. The inner end of rod 6l is provided with a nut S'l thereon having a4 screw threaded engagement therewith. A resilient spacer 58 is'located between a washer 53 and a metal'wash'er llt, which is electrically connected, as by welding metal to the end portion l'andthe rod di. v Y Y That Apart of the outer end of rod 8l which is not covered by refractory electric-insulating supports ll is covered'by agtubular member 69,'also of electric-insulating;materialwhich is adapted to withstand stresses.'Y The inner end of tube 69 abuts against one spacer 53. Theouter end portion 59 has relatively` heavy compressive electrically secured thereto a relatively heavy lead ll, as by Welding thereto, which extends' Vaxially outwardly and has connected thereto a terminal member i3. A tube 'l5 of electric insulating material surrounds lead or terminal 1I.

A spacer 'll of electric insulating-materialV abuts against the outer end of tube BS and may also abut against the outer end of tube 75. An auxiliary Washer I9 is located adjacentto the Youter face of Yspacer 'El and fits Within the tube Il. A washer Bl of resilient electric-insulating material 'is located against the outer face of Washer 'i9 and a relatively heavy washer 83 whichY Ymay be of refractory material is locatedV against the outer face of member 8l. The outer end of rod 6l is provided with screw threads to receive a nut 85. A terminal 8l, of strap form, may be clamped to the outer end of rod 6i as by a clamp- Y Vupon the upper end of the tube Il Vin Which the particular heating unit is located.

Referring now to Fig. 2 of the drawings, attention iscalled particularly to the other use of Vthe layer 2l' of electric-insulating material which, as shown in that figure of the drawings, may either directly engage the upper end of` rod 6i or the terminal structure including the terminal 8l,

in order to insure that vthe respective individual heating units will be held in their proper operative positions in the fire tubes il without rattle or noise if a boiler of this kind should be located on a moving vehicle such as an electricV locomotive.

The resilient spacer 68 permits of unequal expansion and contraction of the alined parts of the heating unit during operation.

If it is necessary to replace a damaged heating unit this can be done while the boiler is hot, by removing the top or cover V2l and the electricinsulating material 2l and disconnecting the terminal leads '13 and 8l of the damaged heating unit, after which the heating unit can be removed and a new one put in place, the electrical connections made and the cover put back in place. 1

The device embodying my invention itself provides a very simple construction of a steam boiler utilizing a plurality of elongated electric heating units located within a plurality of iire tubesr in the boiler into which theymay be introduced and from which they may be removed in a very quick and simple manner.

Various modifications may be made in the device embodying my invention without departing from the spirit and scope. thereof and I desire, therefore, that only such limitations shall be embodied therein as are imposed by the priorv art or set forth in the appended claims.

' I claim as my invention: Y

, 1. A tube for water boilershaving a heating unit therein including a helically wound resistor, aV plurality of peripherally-grooved refractory resistor supports, each of 'less than 180 peripheral extent Vwithin the helically wound resistor and a metal rod extending between the refractory supports to force the same radially into the convolutions of the resistor.

2. A tube for water boilers having a heating unit therein including a preformed helicallywound relatively heavy resistor wire, a plurality of elongated peripherally grooved co-extensive refractory resistor suppo-rts, each of less than 180 peripheral extent within the helically-wound resistor and a metal rod extending between the refractory supports and engaging the same to cause the resistor to t into the grooves in the supports.

3. A tube for water boilers having a heating unit therein including a relatively heavy resistor wire pre-formed to helical shape, a plurality of similar co-extensive externally grooved refractory resistor supports, and a metal rod located between the refractory supports to force them outwardly and cause the grooves therein to tightly receive the respective turns of the resistor wire, and an electrical connection between one end of the metal rod and the corresponding end of the resistor wire.

4. A tube for water boilers having a heating unit therein including a relatively heavy resistor wire pre-formed to comprise a plurality of sets of helically wound turns connected by short axial portions, a plurality of similar elongated coextensive externally-grooved refractory supports in each set of helical turns of the resistor wire, refractory spacers between successive pairs of refractory supports, each of said spacers having a notch in its peripheral edge to receive the axial portion of the resistor, a metal rod extending inside the refractory resistor supports to space them apart and cause the grooves thereon to receive the resistor wire and an electrical connection between the inner end of the rod and the inner end of the resistor wire.

5. A tube for water boilers having a heating unit therein including a relatively heavy resistor wire pre-formed to comprise a plurality of sets bf helically wound turns connected by short axial portions, a plurality of similar elongated co-extensive externally-grooved refractory resistor supports in each set of helical turns of the resistor wire, refractory spacers between successive pairs of refractory supports, each of said spacers having a notch in its peripheral edge to receive the axial portion of the resistor, a metal rod extending inside the refractory resistor supports to space them apart and cause the grooves thereon to receive the resistor wire, an electrical connection between the inner end of the rod and the inner end of the resistor wire, and a pair of terminals at the outer end of the metal rod.

6. A tube for water boilers having a heating unit therein comprising a helically wound relatively heavy resistor member, externally-grooved elongated refractory resistor supports within the helically wound resistor, a metal rod extending between the resistor supports to cause the grooves to receive the turns of the resistor wire, spacers on the rod to hold the heating unit substantially coaxial with the tube in which it is located, an end washer on the outer end of the rod of larger diameter than the tube and abutting against one end of the tube and a covering sheet of electricinsulating material carried by the casing adjacent to said end washer to hold the heating unit in the tube.

7. A fire tube for water boilers having a heating unit therein of elongated shape and comprising a resilient washer of larger diameter than the tube and supporting the heating unit from and on one end of the re tube.

8. A re tube for Water boilers having an elongated heating unit therein comprising a rod, refractory resistor supports on the rod, a resistor supported by the refractory supports, nuts on the rod at each end thereof and a resilient spacer on the rod intermediate the nuts to compensate for unequal expansion of the parts between the nuts relatively to the expansion of the rod.

ORA A. COLBY.

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