US1622621A - Electric furnace - Google Patents

Electric furnace Download PDF

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US1622621A
US1622621A US38980A US3898025A US1622621A US 1622621 A US1622621 A US 1622621A US 38980 A US38980 A US 38980A US 3898025 A US3898025 A US 3898025A US 1622621 A US1622621 A US 1622621A
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Prior art keywords
hanger
block
resistor
furnace
opening
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US38980A
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James C Woodson
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CBS Corp
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Westinghouse Electric and Manufacturing Co
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    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B3/00Ohmic-resistance heating
    • H05B3/62Heating elements specially adapted for furnaces
    • H05B3/66Supports or mountings for heaters on or in the wall or roof

Definitions

  • My invention relates to electric furnaces and particularly to resistor-supporting means therefor.
  • An object of my invention is to provide a relatively simple and easily removable resistor-supporting member for an electric furnace.
  • I provide a metal member located in a wall of the furnace and having a therein and hanger locks having an end portion extending into an opening and interlocked with the metal member.
  • a spacing member, of electric-insulating material, is located on the hanger block and aids in supporting the same in proper operative positlon.
  • Fig. 1 is a view in vertical longitudinal section of an electric furnace embodying my invention
  • Fig. 2 1s a fragmentary view in rear elevation of a device embodyin my invention.
  • Fig. 3 is a view in vertica lateral section therethrough taken on the line IIIIII of Fig. 2,
  • ig. 4 is a view, in front-elevation, of a spacer member, I
  • Fig. 5 is a view, in side elevation. of a hanger block
  • Fig. 6 is a view, in rear el ation, of a hanger block, v
  • Fig. 7 is a top plan view of 'a hanger block
  • Fig. 8 is a fra mentary view, in rear elevation, of a mo lfied form of device embodyin my invention.
  • An e ectric furnace 11 comprises the usual plurality of walls that may be built up of a plurality of bricks or blocks of heat-insulatmg an hightemperature-resisting refractory material usually employed in the art.
  • the bricks or blocks are so arranged and disposed as toenclose a furnace chamber 13 of any suitable or desired contour and dimensions.
  • a furnace chamber 13 of any suitable or desired contour and dimensions.
  • Each wall of the furnace structure that is to have associated therewith a resistor member is provided with a slot or groove 14 that may extend horizontally in the wall.
  • the opening 16 comprises a relatively large intermediate portion that is substantially circular in shape,-and that has associated therewith two extensions 17 and 18, respectively, which may be located at an angle of substantially from the central longitudinal axis of the member 15.
  • Integral ortions 19 and 21 each of substantially -sha are provided adjacent to the top and the fittom of each of the 0 enings 16 in the member 15 and com rise u s or bosses of a suitable depth latera ly of tile member 15, the general proportions thereof being substantially as indicated in Figs. 2 and 3.
  • the space between the two lugs of the members or portions 19 and 21 is substantially the same asthat covered by the openings 17 and 18.
  • a plurality of hanger blocks 22. of refractory electric-insulating material severally comprise an elongated portion 23 that may be substantially circular in lateral section. and that is provided at the rear end portion thereof with two laterally extending age 24 and 25 that are located diametra'lly opposite thereon.
  • the members 22 are further provided with a front end portion 26 that is somewhat larger, in lateral extent, than the portion 23, in order to prevent a resistor member. that is supported by the orward part of the portion 23 from eing disengaged therefrom.
  • the size or dimensions of the portion 23 and of the integral extensions 24 and 25 are such that they will fit into the opening 16 having extensions 17 and 18.
  • a spacer 27, of refractory electric-insulating material, is substantially square in sec hanger block has been moved into its nortion and is provided with an opening 28 therein that has substantially the same irregular contour and that is of substantially the same dimensions as was hereinbefore de scribed in connection with the openings 16, 17 and 18. r I
  • the respective members 22 may have located thereon the spacer plates 27 by in-' serting the rear end portion thereof through the openings 28 before they are inserted in the opening 16 In the member 15.
  • the inner block is interthe member 15 (if channelsechanger block relative to the member of chan' nel section is efiectuaily prevented.
  • the spacer block 27 is then moved along the intermediate portion 23 of the hanger block until its inner surface operatively engages or is closely adjacent to the outer surface of the central: flange of the -member 15.
  • the weight of spacer memher 27 is supported by the portion'of the wall immediately ad'acent to the groove 14 and the spacer mem er 27 is thereby made effective to support a ortion or all of the weight of the hanger lock and also of a resistor member 29 that is supported by the lurality of hanger blocks.
  • the resistor member as being constituted by a ribbon of a suitable resistor material such as-nichrome, that is bent to comprise a plurality of substantially parallel-extending loop portions, the resistor member being supporte per ends of the respective loops located over 7 the respective hanger blocks' lhe length of the hanger-blocks back of v the front part 26 and the thickness of the s acer member 27 located therein is such t at the space therebetween is just cient to receive the resistor member 29
  • Means for insuring that the bottom portions of the respective adjacent loops of the resistor member shall not engage each other are constituted by refractory lugs or rods 31 that may be built-to the furnace wall ad- ⁇ acent to the lower ends of the respective oops, substantially as illustrated in Fig. 1 of the drawing.
  • Fig. 8 illustrates a modified form of a hanger block 32, and of amember 33 of channel section.
  • the member 33 is provided with a plurality of openings 34 therethrough having'substantially the same extensions as were hereinbefore described in connection with the' openings 16 but these extensions are located in a direction substantially laterally of the member 33.
  • the integral lug portions 24 and 25, as were hereinbefore described for the hanger blocks 22, are located at a somewhat diiferent angle inorder that they may be located in a substantiallyhorizontal planewhen the hanger block is in its normal operative position and interlocked with-the member 33.
  • the hanger block 32 at the left-hand end of Fig. 8 illustrates. the extensions thereon in their normal operative positions and are shown as inter-fitting with two longitudinally extending ribs 35 and 36 that extend between the spaced openings 34..
  • the hanger block 32 is inserted in substantially the same manner, that is, angularly displaced relative to its normal .operative position, and is moved back far enough so that the lateral extensions on the member 32 will clear theintegral ribs 37 and 38 of substantially Y-shape, after which the 1 L1 block may be turned through substantiall and be pulled forward 30 interlocir't e same.
  • A. spacer member 1 may be located on the respective hanger blocks 32 and will operate in substantially the same manner .as hereinbefore described in connection with the members 23.
  • the ribs 35 and 36 serve also to strengthen the central flange of the member 33 to counteract, to some degree, the weakening effect of the open- .t-z r 1 he device embodying my invention thus provides a hen er block that is easily and quickly inserts in and removed from its interlocked relation with a member of substantially channel-shape in lateral section, and that has associated therewith a spacer member that serves to support the hanger block.
  • Thehanger -bloclr is maintained in its normal operative and interlocked position relatively to themember of channel section by the resistor member.
  • a member of substantially channel. section in combination, a member of substantially channel. section, and a hanger block for supporting a resistor member extending into said member of channel section and held in proper operative osition therein-by the resistor.
  • an electric furnace in combination, a member of substantially channel section, and a hanger block for supporting a resistor member extending into said member of channel section and interlocked therewith, and held in said interlocked position by the resistor.
  • a member of substantially channel section having a plurality of openings therein, and hanger blocks for supporting a resistor member, and extending into said member through said openings and interlocked "with said member of channel section.
  • a member of substantially channel section having an opening therein, and a hanger block for a resistor member movable into said opening angularly displaced from its normal operative position, and interlocked with said member of channel section when in its normal operative position therein.
  • a member of substantially channel section having an opening therein, and a hanger block for a resistor member movable into said opening angularly displaced from its normal operative position, and interlocked with said member ,of channel section when in its normal operative position therein and held therein by the resistor member.
  • a han er block for supporting a resistor, a member located in a wall of said furnace having an opening therein for receiving an end portion of sa1d han er block, and lugs integral with said member for interfitting with said hanger block and preventing ⁇ )neovement thereof relatively to said mem- 7.
  • a ban er block for supporting a resistor, a mem er located in a wall of said furnace having an opening therein for receivin an end portion of said hanger block, and ugs integral with said member for interfitting with said hanger bloc-k and preventing movement thereof relatively to said member, said hanger block being held in said interfittin position by the resistor.
  • a ban er block for supporting a resistor, a memIJer located in a wall of said furnace having an opening therein throu h which one end of said hanger block may e inserted when turned a predetermined an lar amount from the normal operative position, and lugs integral with the said member for interfitting with said hanger block when in its normal operative position.
  • a hanger block for supporting a resistor
  • a member located in a wall of said furnace having an opening therein through which one end of said hanger block may be inserted when turned a predetermined an ular amount from the normal operative position, and lugs integral with the member for interfitting with said hanger block when in its normal operative position, saidhanger block being held in said interfitting position by the resistor.
  • a hanger block having a portion extending through said opening, for supporting a resistor member, and a spacing member, of refractory electric-insulating material, on said hanger block and having one face in operative engagement with the front face of said member located in the furnace wall and co-operating with said wall to support said hanger block.
  • a member located in a wall of the furnace and having an opening therethrou'gh, a hanger block, having one end extending into the opening and lnterfitting with said member, for supporting a resistor member, and a spacing member of refactory electricinsulating material, located on said hanger block in operative engagement with one face of said member located in the furnace wall and cooperatin with the resistor to hold the hanger bloc in interfitting relation in said member.
  • a member located in a wall of the fur nace and having an opening therethrough, a hanger block, having one end extendin into the opening and interfitting with said member, for supporting a resistor member, and a spacing member, of refractory electricinsulating material, located on said hanger block in operative engagement with one face of said member located in the furnace wall, co-operating with said wall to support said hanger block and cooperating with the resistor to hold the hanger block in interfitting relation in said member.

Description

March 29 1927. ,6 1
J. c. WOODSON ELECTRIC FURNACE Filed June 23, 1925 WgNESSES: INVENTOR fi. 9% 3 James C. M00800 ATTbRNEY Patented Mar. 29, 1927.
UNITED STATES PATENT OFFICE.
JAIES C. WOODSON, OF EAST PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WEST- INC-HOUSE ELECTRIC 8a MANUFACTURING COMPANY, A CORPORATION 01' PENN- SYLVANIA.
ELECTRIC FURNACE.
Application filed June 23, 1925. Serial No. 88,980.
My invention relates to electric furnaces and particularly to resistor-supporting means therefor.
An object of my invention is to provide a relatively simple and easily removable resistor-supporting member for an electric furnace.
' In practicing my invention, I provide a metal member located in a wall of the furnace and having a therein and hanger locks having an end portion extending into an opening and interlocked with the metal member. A spacing member, of electric-insulating material, is located on the hanger block and aids in supporting the same in proper operative positlon.
In the single sheet of drawings,
Fig. 1 is a view in vertical longitudinal section of an electric furnace embodying my invention Fig. 2 1s a fragmentary view in rear elevation of a device embodyin my invention.
Fig. 3 is a view in vertica lateral section therethrough taken on the line IIIIII of Fig. 2,
ig. 4 is a view, in front-elevation, of a spacer member, I
Fig. 5 is a view, in side elevation. of a hanger block,
Fig. 6 is a view, in rear el ation, of a hanger block, v
Fig. 7 is a top plan view of 'a hanger block, and
Fig. 8 is a fra mentary view, in rear elevation, of a mo lfied form of device embodyin my invention.
An e ectric furnace 11 comprises the usual plurality of walls that may be built up of a plurality of bricks or blocks of heat-insulatmg an hightemperature-resisting refractory material usually employed in the art. The bricks or blocks are so arranged and disposed as toenclose a furnace chamber 13 of any suitable or desired contour and dimensions. As the particular construction and arrangement of the furnace walls forms f no art of my invention, it is not illustrated or escribed in detail.
Each wall of the furnace structure that is to have associated therewith a resistor member is provided with a slot or groove 14 that may extend horizontally in the wall. A
lurality of openings t metal member '15 of substantially channelshape in lateral section, is located in the groove 14 with the laterally-extending members engagin the inner wall or bottom of the groove su stantially as illustrated in Fig. 1 of the drawing. The depth of the groove 14. is such that the metal member 15 will be located below the surface of the wall for a purpose to be hereinafter set forth in de- The member 15 is provided with a plurality of symmetrically spaced openings 16 in the intermediate ange portion of the member, each of the openings 16 being of irregular contour. As illustrated articularly in Figs. 1 and 2of the drawing, the opening 16 comprises a relatively large intermediate portion that is substantially circular in shape,-and that has associated therewith two extensions 17 and 18, respectively, which may be located at an angle of substantially from the central longitudinal axis of the member 15.
Integral ortions 19 and 21, each of substantially -sha are provided adjacent to the top and the fittom of each of the 0 enings 16 in the member 15 and com rise u s or bosses of a suitable depth latera ly of tile member 15, the general proportions thereof being substantially as indicated in Figs. 2 and 3. The space between the two lugs of the members or portions 19 and 21 is substantially the same asthat covered by the openings 17 and 18.
A plurality of hanger blocks 22. of refractory electric-insulating material severally comprise an elongated portion 23 that may be substantially circular in lateral section. and that is provided at the rear end portion thereof with two laterally extending age 24 and 25 that are located diametra'lly opposite thereon. The members 22 are further provided with a front end portion 26 that is somewhat larger, in lateral extent, than the portion 23, in order to prevent a resistor member. that is supported by the orward part of the portion 23 from eing disengaged therefrom. The size or dimensions of the portion 23 and of the integral extensions 24 and 25 are such that they will fit into the opening 16 having extensions 17 and 18.
A spacer 27, of refractory electric-insulating material, is substantially square in sec hanger block has been moved into its nortion and is provided with an opening 28 therein that has substantially the same irregular contour and that is of substantially the same dimensions as was hereinbefore de scribed in connection with the openings 16, 17 and 18. r I
The respective members 22 may have located thereon the spacer plates 27 by in-' serting the rear end portion thereof through the openings 28 before they are inserted in the opening 16 In the member 15. In order to insert the hanger blocks, it is necessary to displace them 'angularly from their locked wit tion, whereby any turning movement of the normal operative position so that the lugs 24 and will fit into the openin s' 17 and 18, when the hanger block may e moved longitudinally of its own axis into the opening 18. It 1s moved inwardly a suficient distance to permit the extensions 24 and 25 to clear the portions 19 and 21, after which the member is turned through an angle of substantially or until the extensions 24 and 25" are all ed with the spaces between the two In s o the portions 19v and 21 after which the anger-block is moved forwardly so that e. ortions 24 and 25 fit into the space provi ed therefor, the normal operative position as seen from the rear bein shown more particularly in the lefthand en of Fig. 2 of the drawing.
In this ition the inner block is interthe member 15 (if channelsechanger block relative to the member of chan' nel section is efiectuaily prevented. The spacer block 27 is then moved along the intermediate portion 23 of the hanger block until its inner surface operatively engages or is closely adjacent to the outer surface of the central: flange of the -member 15.
' in this sition, the weight of spacer memher 27 is supported by the portion'of the wall immediately ad'acent to the groove 14 and the spacer mem er 27 is thereby made effective to support a ortion or all of the weight of the hanger lock and also of a resistor member 29 that is supported by the lurality of hanger blocks.
, 1i" 'ave illustrated the resistor member as being constituted by a ribbon of a suitable resistor material such as-nichrome, that is bent to comprise a plurality of substantially parallel-extending loop portions, the resistor member being supporte per ends of the respective loops located over 7 the respective hanger blocks' lhe length of the hanger-blocks back of v the front part 26 and the thickness of the s acer member 27 located therein is such t at the space therebetween is just cient to receive the resistor member 29 By this means, it is possible to maintain the hanger block in its interlocked position relativelyto the member 15 of channel section, after the by having the up-..
weasel mal operative. position as was hereinbefore described.
' Means for insuring that the bottom portions of the respective adjacent loops of the resistor member shall not engage each other are constituted by refractory lugs or rods 31 that may be built-to the furnace wall ad- {acent to the lower ends of the respective oops, substantially as illustrated in Fig. 1 of the drawing.
Fig. 8 illustrates a modified form of a hanger block 32, and of amember 33 of channel section. The member 33 is provided with a plurality of openings 34 therethrough having'substantially the same extensions as were hereinbefore described in connection with the' openings 16 but these extensions are located in a direction substantially laterally of the member 33. The integral lug portions 24 and 25, as were hereinbefore described for the hanger blocks 22, are located at a somewhat diiferent angle inorder that they may be located in a substantiallyhorizontal planewhen the hanger block is in its normal operative position and interlocked with-the member 33. The hanger block 32 at the left-hand end of Fig. 8 illustrates. the extensions thereon in their normal operative positions and are shown as inter-fitting with two longitudinally extending ribs 35 and 36 that extend between the spaced openings 34..
The hanger block 32 is inserted in substantially the same manner, that is, angularly displaced relative to its normal .operative position, and is moved back far enough so that the lateral extensions on the member 32 will clear theintegral ribs 37 and 38 of substantially Y-shape, after which the 1 L1 block may be turned through substantiall and be pulled forward 30 interlocir't e same. A. spacer member 1 may be located on the respective hanger blocks 32 and will operate in substantially the same manner .as hereinbefore described in connection with the members 23. .The ribs 35 and 36 serve also to strengthen the central flange of the member 33 to counteract, to some degree, the weakening effect of the open- .t-z r 1 he device embodying my invention thus provides a hen er block that is easily and quickly inserts in and removed from its interlocked relation with a member of substantially channel-shape in lateral section, and that has associated therewith a spacer member that serves to support the hanger block. Thehanger -bloclris maintained in its normal operative and interlocked position relatively to themember of channel section by the resistor member.
lie I have illustrated and described a specific embodiment of a haner block and or a member of channel section, 1 do not wish to be liihited to the particular construction shown and described as departures may be made therefrom and all such modifications are intended to be covered by the appended claims which are to be limited on y by the prior art.
I claim as my invention:
1. In an electric furnace, in combination, a member of substantially channel. section, and a hanger block for supporting a resistor member extending into said member of channel section and held in proper operative osition therein-by the resistor.
2. 11 an electric furnace, in combination, a member of substantially channel section, and a hanger block for supporting a resistor member extending into said member of channel section and interlocked therewith, and held in said interlocked position by the resistor.
3. In an electric furnace, in combination, a member of substantially channel section having a plurality of openings therein, and hanger blocks for supporting a resistor member, and extending into said member through said openings and interlocked "with said member of channel section.
4. In an electric furnace, in combination, a member of substantially channel section having an opening therein, and a hanger block for a resistor member movable into said opening angularly displaced from its normal operative position, and interlocked with said member of channel section when in its normal operative position therein.
5. In an. electric furnace, in combination, a member of substantially channel section having an opening therein, and a hanger block for a resistor member movable into said opening angularly displaced from its normal operative position, and interlocked with said member ,of channel section when in its normal operative position therein and held therein by the resistor member.
6. In an electric furnace, in combination, a han er block for supporting a resistor, a member located in a wall of said furnace having an opening therein for receiving an end portion of sa1d han er block, and lugs integral with said member for interfitting with said hanger block and preventing {)neovement thereof relatively to said mem- 7. In an electric furnace, in combination, a ban er block for supporting a resistor, a mem er located in a wall of said furnace having an opening therein for receivin an end portion of said hanger block, and ugs integral with said member for interfitting with said hanger bloc-k and preventing movement thereof relatively to said member, said hanger block being held in said interfittin position by the resistor.
8. 11 an electric furnace, in combination,
a ban er block for supporting a resistor, a memIJer located in a wall of said furnace having an opening therein throu h which one end of said hanger block may e inserted when turned a predetermined an lar amount from the normal operative position, and lugs integral with the said member for interfitting with said hanger block when in its normal operative position.
9. In an electric furnace, in combination, a hanger block for supporting a resistor, a member located in a wall of said furnace having an opening therein through which one end of said hanger block may be inserted when turned a predetermined an ular amount from the normal operative position, and lugs integral with the member for interfitting with said hanger block when in its normal operative position, saidhanger block being held in said interfitting position by the resistor.
10. In an electric furnace, in combination, a member located in a wall of the furnace and having an opening therein, a hanger block, having a portion extending through said opening, for supporting a resistor member, and a spacing member, of refractory electric-insulating material, on said hanger block and having one face in operative engagement with the front face of said member located in the furnace wall and co-operating with said wall to support said hanger block.
11; In an electric furnace, in combination, a member located in a wall of the furnace and having an opening therethrou'gh, a hanger block, having one end extending into the opening and lnterfitting with said member, for supporting a resistor member, and a spacing member of refactory electricinsulating material, located on said hanger block in operative engagement with one face of said member located in the furnace wall and cooperatin with the resistor to hold the hanger bloc in interfitting relation in said member.
12. In an electric furnace, in combination, a member located in a wall of the fur nace and having an opening therethrough, a hanger block, having one end extendin into the opening and interfitting with said member, for supporting a resistor member, and a spacing member, of refractory electricinsulating material, located on said hanger block in operative engagement with one face of said member located in the furnace wall, co-operating with said wall to support said hanger block and cooperating with the resistor to hold the hanger block in interfitting relation in said member.
In testimony whereof, I have hereunto subscribed my name this 11th day of June JAMES C. WOODSON.
US38980A 1925-06-23 1925-06-23 Electric furnace Expired - Lifetime US1622621A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3506771A (en) * 1968-10-10 1970-04-14 Stephen F Cole Jr Modularly constructed heating elements for electric furnaces
US4573164A (en) * 1984-02-16 1986-02-25 Combustol Industria E Comercio Ltda. Support for electrical resistances of ovens or kilns with ceramic mantle thermal insulation

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3506771A (en) * 1968-10-10 1970-04-14 Stephen F Cole Jr Modularly constructed heating elements for electric furnaces
US4573164A (en) * 1984-02-16 1986-02-25 Combustol Industria E Comercio Ltda. Support for electrical resistances of ovens or kilns with ceramic mantle thermal insulation

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