US2080798A - Air conditioning apparatus - Google Patents

Air conditioning apparatus Download PDF

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US2080798A
US2080798A US80285A US8028536A US2080798A US 2080798 A US2080798 A US 2080798A US 80285 A US80285 A US 80285A US 8028536 A US8028536 A US 8028536A US 2080798 A US2080798 A US 2080798A
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casing
heating
air
elements
housing
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US80285A
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Edwin L Wiegand
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Edwin L Wiegand Co
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Edwin L Wiegand Co
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H3/00Air heaters
    • F24H3/02Air heaters with forced circulation
    • F24H3/04Air heaters with forced circulation the air being in direct contact with the heating medium, e.g. electric heating element
    • F24H3/0405Air heaters with forced circulation the air being in direct contact with the heating medium, e.g. electric heating element using electric energy supply, e.g. the heating medium being a resistive element; Heating by direct contact, i.e. with resistive elements, electrodes and fins being bonded together without additional element in-between
    • F24H3/0411Air heaters with forced circulation the air being in direct contact with the heating medium, e.g. electric heating element using electric energy supply, e.g. the heating medium being a resistive element; Heating by direct contact, i.e. with resistive elements, electrodes and fins being bonded together without additional element in-between for domestic or space-heating systems

Definitions

  • This invention relates to air conditioning apparatus and has for its principal object the provision of new and improved apparatus of this character.
  • Figure 1 is a vertical sectionalview of the invention, showing parts in elevation
  • Figure 2 is a front elevational view of the invention, with portions thereof broken away to disclose the interior construction
  • Figure 3 is a fragmentary, enlarged, broken vertical sectional view corresponding substantially to the line 3-3 of Figure 2,
  • Figure 4 is an enlarged fragmentary perspective view of one portion of the apparatus
  • Figure 5 is a rear elevational view of the invention showing one manner of supporting the motor and fan unit
  • Figure 6 is a similar view showing a different embodiment of the motor and fan supporting means
  • Figure 7 is a side elevational view of a thermally responsive means employed in connection with the invention, and showing the parts in one position,
  • Figure 8 is a vertical sectional view of the thermally responsive means taken on the line 8-8 of Figure 9, and disclosing the parts in a difierent position,
  • Figure 9 is a top plan view, partlyin section, of the thermally responsive means shown in Figures 7 and 8, while Figure 10 is a diagrammatic layout of the electrical appliances employed in connection with the invention.
  • the embodiment of the invention shown in Figures 1 through 5, 7 through 9, and Figure 10, comprises a metallic casing 20, preferaby oblong rectangular in cross-section and open at both ends. Adjacent one end of the casing 20 is disposed a plurality of electrical heating elements 2
  • each heating element 21 Arranged along the body portion 22 of each heating element 21, is a plurality of laterally extending fin members 23, each having a central aperture surrounded by a flange 29, and so disposed that 5 the flanges 29 are arranged in overlapping abutting relation, the flns 26 providing large radiating surfaces and operating also to provide air passages therebetween which direct passing air 10
  • Supporting the heating elements 21 in proper position in the casing 20 are supporting means comprising a support 30 for one set of ends of the heating elements 2 l, and a support 3
  • Each of the supports 30 and 31 comprises a pair of end blocks 32, over which is fitted an angular section 33, having a flange 34 welded to one end of the block 32, as at 35, and having a flange 36 welded to the top of the block, and the flange 36 is provided with a plurality of slots 31, each beginning adjacent the corner of the section 33, and extending outwardly and opening at the free edge of the flange 36.
  • Each slot 31 is adapted for the reception of one end of the rectangular body portion 22 of an individual heating element 21, and the body portion 22 of each heating element is maintained in position in each slot 31 by means of a plate 49 detachably secured to the opposite end of each block 32, as by a screw 41 tapped into the block, the plate 40 being provided with an angular flange 42 which lies snug against the edge of the flange 36 and spans the mouths of the slots 31, to close the same, and the plate also cooperates with the section 33, and the blocks 32. to define a hollow formation characteristic of both supports 30 and 31, and within which the 40 projecting ends of the body portions 22 of the heating elements are accommodated.
  • the spaced supporting formations 30 and 3i are tied together by side bars 43 having their ends secured to the blocks 32 by welding or the like, as at 44, and the 45 side bars 43 are secured to the casing 20 by screws 45 threaded into tapped holes 46 extending through the side bars 43 and into the blocks 32.
  • may be inserted laterally into the slots 31, with the flange 36 extending between the adjacent end pair of fins 28, the latter preferably being placed closer together than the remainder of the fins to insure snug reception of the flange a 38 the heating elements 2
  • housed within the hollow formation of the support 3
  • a partition 55 having angular flanges 58 secured to the casing wall by bolts 51, and the partition 55 is provided with a central aperture 58 ing a flange 10 secured to the partition 55 by the armature shaft of a motor 80.
  • the motor 80 is supported in position with respect to the casing 20, by feet 8
  • FIG. 6 A somewhat different embodiment of motor mounting is shown in Figure 6, in this case comprising a supporting member having a cradle portion 81 secured by screws to the motor casing, and connected by struts 68 to a ring 59 having a flange 18 secured to the partition 55 by screws 1
  • are connected in parallel circuits 12, I3, and 74, the circuits 13 and 14 connecting through jumper straps and '16 with the conductors I! and 18, the jumper straps in the positions shown in full lines in Figure 10, rendering the system suitable for single phase operation.
  • the jumper straps I5 and 18 may be rearranged, as indicated in dotted lines in Figure 10, to connect with a conductor 19, and thus render the system suitable for threephase operation.
  • the conductors TI, 18 and 19 are adapted to be connected with feed wires through a switch 88.
  • Control mechanism is included in a parallel circuit 8
  • the motor and fan unit may be included in another circuit not affected by the making and breaking of the circuit 8
  • My invention also contemplates the interposition of a safety cut-out device 84, within the control circuit 8
  • the safety thermal cut-out comprises an elongated metallic block 85 secured by bolts to the plate 34 of the supporting formation 8
  • the block 85 is also provided with an offset portion 93 to which is secured a bimetallic thermally responsive element 94, and to the opposite side of the block 85 is secured a resilient latch member 95 having a screw extending laterally therethrough providing an adjustable post 96 which extends between the contact members 85 and 81 and into abutment with the thermally responsive element 94, and beyond the post 98 the latch memher 95 is provided with a laterally extending portion having an engaging face 91 adapted in one position to bear against the extension 88 to hold the contacts 88 in engagement, and also having a beveled surface 88 to facilitate movement of the extension 89 into latching position when the extension 89 is moved by manipulation of the rod 98 to reset the latch after the same has been detached.
  • the fan will operate to direct air through the casing 28, and through and into contact with the heating elements 2
  • Due to the manner in which the heating elements 2
  • may be operated in concert, as just described, but, if desired, the heating units in the circuits [3 and/or 14 may be cut out temporarily by disconnecting the jumper straps 15 and/or I6.
  • is eilected through operation of the thermostatically controlled switch 82 which interrupts the circuit 8
  • the circuit 8! is again closed, resulting in closing of the switch 80, and energization of whatever heating elements are included in the circuit.
  • the safety thermal cut-out 84 is located adjacent to the heating coils 2
  • the safety cut-out deenergizes the circuit 8
  • Heating apparatus comprising: a casing through which air is adapted to be directed; an elongated heating element extending across the passage provided by said casing and adapted to be traversed by air passing through said casing, said heating element having a body portion and a plurality of laterally extending longitudinally spaced fins thereon; and means carried by said casing for holding said heating element in position, said means having a wall slotted for the lateral reception of the body portion of said heating element, with said wall disposed between adjacent fins on said body portion.
  • Heating apparatus comprising: a casing through which air is adapted to be directed; an elongated heating element extending across the passage provided by said casing and adapted to be traversed by air passing through said casing; and means carried by said casing for holding said heating element in position, said means having a wall provided with an open-ended slot for the reception of the body portion of said heating element; and a member detachably secured in position to close the open end of said slot to maintain said heater in position therein.
  • Heating apparatus comprising: a casing through which air is adapted to be directed; an elongated heating element extending across the passage provided by said casing and adapted to be traversed by air passing through said casing, said heating element having a body portion and a plurality of laterally extending longitudinally spaced fins thereon; and means carried by said casing for holding said heating element in position, said means having a wall provided with an open-ended slot for the lateral reception of the body portion of said heating element with said wall disposed between adjacent fins on said body portion; and a member detachably secured in position to close the open end of said slot.
  • Heating apparatus comprising: a casing through which air is adapted to be directed; an elongated electrical heating element extending across the passage provided by said casing and adapted to be traversed by air passing through said casing; means carried by said casing and having walls cooperating with said casing to provide a hollow'formation for the accommodation of the end portion of said heating element; and
  • Heating apparatus comprising: a casing through which air is adapted to be directed; a plurality of spaced elongated electrical heating elements extending across the passage provided by said casing and adapted to be traversed by air passing through said casing; means carried by said casing adjacent the opposite ends of said heating elements, and each having walls cooperating with a wall of said casing to provide a hollow formation for the accommodation of the opposite end portions of said heating elements and having connecting members connecting the opposite end portions of said hollow formations to form a supporting frame; and electrical connections connected with said heating elements and arranged within one of said hollow formations.
  • Heating apparatus comprising: a casing through which air is adapted to be directed; a plurality of elongated electrical heating elements extending across the passage provided by said casing and adapted to be traversed by air passing through said casing; means carried by said casing for securing said heating elements in position, and having walls cooperating with said casing to provide a hollow formation, one of said walls having a plurality of slots for laterally receiving portions of said heating elements.
  • Heating apparatus comprising: a casing through which air is adapted to be directed; and
  • an elongated heating element extending across to the stream of air adapted to pass through said casing, said heating element having a plurality of laterally extending, longitudinally spaced fins, providing means for directing the air in its passage through said casing; and means carried by said casing for holding said heating elements in position, said means havinga wall provided with an open-ended slot adapted for the edgewise reception of said heating element, with said wall disposed between adjacent fins on said heating element.
  • Heating apparatus comprising: a casing through which air is adapted to be directed; an elongated heating element extending across the passage provided by said casing and adapted to be traversed by air passing through said casing, said heating element having a body portion and a plurality of laterally extending longitudinally spaced fins thereon; and means carried by said casing for holding the opposite ends of said heat- 7 ing element in position, said means adjacent one end of said heating element having a wall provided with an open-ended slot for the reception of the body portion of said heating element with said wall disposed between adjacent fins on said body portion, and a wall adjacent its opposite end provided with a slot for the reception of the opposite end of said heating element, said latter wall being spaced from the nearest adjacent fin to permit expansion of said heatingelement.
  • Heating apparatus comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; means for supporting said heating means from the top wall of said housing; means for loosely supporting the bottom of said heating means to permit movement incident to expansion and contraction of said heating means; and means for directing air through said housing structure and about said heating means.
  • Heating apparatus comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; means for supporting said heating means from the top wall of said housing; means for loosely supporting the bottom of said heating means for movement incident to expansion and contraction of said heating means, said means being constructed to limit and guide said movement during such expansion and contraction; and means for directing air through said housing and about said heating means.
  • Heating apparatus comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; means for supporting said heating means from the top wall of said housing; means for loosely supporting the bottom of said heating means for movement incident to expansion and contraction of said heating means, said means being constructed to limit and guide said movement, and including a slot, and means carried by said heating element slidably accommodated in said slot; and means for directingair through said housing and about said heating means.
  • Heating apparatus comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; means for supporting said heating means from the top wall of said housing, including a slotted portion, means carried by said heating means projecting through the slot of said slotted portion, and having an abutment resting upon the wall defining said slot, thus to suspend said heating means; means for loosely supporting the bottom of said heating means to permit movement incident to expansion and contraction of said heating means; and means for directing air through said housing and about said heating means.
  • Heating apparatus comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; means for supporting said heating means from the top wall of said housing, including a slotted portion, means carried by said heating means projecting through the slot of said slotted portion and having an abutment engaging the walls defining said slot, thus to suspend said heating means; means for loosely supporting the bottom of said heating means for movement incident to expansion and contraction of said heating means, said means being constructed to limit and guide said movement during such expansion and contractio::, including a slot, and means carried by said heating element slidably accommodated in said 5101;
  • Heating apparatus comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; means for supporting said heating means from the top wall of said housing; means for loosely supporting the bottom of said heating means for movement incident to expansion and contraction of said heating means, said means being constructed to limit and guide said movement during such expansion and contraction, including a slot, and means carried by said heating element slidably accommodated in said slot; part of said bottom supporting means being removable to permit ready detachment of said heating means therefrom; and means for directing air through said housing structure and about said heating means. 15.
  • Heating apparatus comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; top supporting means for supporting said heating means from the top wall of said housing, including a slotted portion, means carried by said heating means projecting through the slot of said slotted portion and having an abutment engaging the walls defining said slot, thus to suspend said heating means; bottom supporting means for loosely supporting the bottom of said heating means for movement incident to expansion and contraction of said heating means, said means being constructed to limit and guide said movement during such expansion and contraction, including a slot, and means carried by said heating element slidably accommodated in said slot; said top and bottom supporting means each having a removable part to permit ready removal of said heating means from said housing structure; and means for directing air through said housing structure and about said heating means.
  • a housing structure a heater including a casing, a resistor within said casing, and terminals for said resistor, carried by said casing; said casing, resistor and terminals forming a unit mountable in and removable from said housing structure; and means including a lateral projection on said casing whereby said heater unit is supported by said casing from said housing structure, whereby the supporting strain is put upon said casing, and said terminals are relieved from the supporting strain.
  • a housing structure including a casing, heating means within said casing; a plurality of laterally extending longitudinally spaced fins on said casing; and
  • Heating apparatus comprising: a housing providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements disposed in said passage, so constructed and arranged that said stream of air is adapted to abstract heat from said heat ing elements; each heating element constituting a unit, so contructed and arranged that each unit is individually mountable in and removable from said housing; and each unit including a plurality of laterally extending longitudinally spaced metallic fins, and heat generating means, individual to each unit.
  • Heating apparatus comprising: a housing providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements disposed in said passage, so constructed and arranged that said stream of air is adapted to abstract heat from said heating elements; each heating element constituting a unit, so constructed and arranged that each unit is individually mountable in and 5 removable'from said housing; and each unit including metallic casing means, and a plurality of laterally extending longitudinally spaced metallic fins on each casing means, and heat generating means, all individual to each unit.
  • Heating apparatus comprising: a housing providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements disposed in said passage, so constructed and arranged that said stream of air is adapted to abstract heat from said heating elements; each heating element constituting a unit, so constructed and arranged that each unit is individually mountable in and removable from said housing; and each unit including metallic casing means having a plurality of laterally extending longitudinally spaced metallic fins, and an electrical resistor embedded in a mass of refractory insulating material in said casing means.
  • Heating apparatus comprising: a housing providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements extending transversely across said passage, constructed and arranged to be traversed by said stream of air; each of said heating elements including metallic casing means and an electrical resistor embedded in a mass of refractory insulating material in said casing means; each of said casing means being constructed oblong in cross-section and arranged edgewise to the stream of air passing through said housing, and presenting the major areas thereof parallel to the general direction of movement of said stream so as to increase the effective areas traversed by said air; and each of said casing means having a plurality of laterally extending longitudinally spaced metallic fins, said fins having continuous surfaces, transverse to said casing means, continuously surrounding said casing means.
  • Heating apparatus comprising: a housing providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements disposed transversely across said passage, so constructed and arranged that said stream of air is adapted to abstract heat from said heating elements; each of said elements including metallic casing means containing an electrical resistor embedded in amass of refractory insulat- 65 ing material in said casing means; the cross-sectional shape of each of said casing means being so constructed and arranged that the dead air space, on the surface of said casing means trailing with respect to said stream, is reduced to thereby increase the area of contact between said stream and said casing means; and each of said casing means having a plurality of laterally ex tending longitudinally spaced metallic fins, said fins having continuous surfaces, transverse to said casing means, continuously surrounding said casing means.
  • Heating apparatus comprising: a housing providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements extending transversely across said passage, constructed and arranged to be traversed by said stream of air; each of said heating elements including metallic casing means and an electrical resistor embedded in a mass of re- 7 fractory insulating material in said casing means;
  • each of said casing means being constructed oblong in cross-section and having side surfaces, and a leading surface, continuous from one of said side surfaces to the other, said leading surface being presented against the stream of air passing 5 through said housing, and said side surfaces being presented parallel to the general direction of movement of the stream so as to increase the effective areas traversed by said air; and each of said casing means having a plurality of longil0 tudinally spaced metallic fins, transverse to said casing means, arranged to present free margins against the stream of air, said margins being spaced away from said leading surface.
  • Heating apparatus comprising: a housing 15 providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements disposed transversely across said passage, so constructed and arranged that said stream of air is adapted to abstract heat from said 20 heating elements; each of said elements including metallic casing means containing an electrical resistor embedded in a mass of refractory insulating material in said casing means; the crosssectional shape of each of said casing means being so constructed and arranged that the dead air space, on the surface of said casing means trailing with respect to the stream of air, is reduced to thereby increase the area of contact between said stream and said casing means, said casing means having side surfaces, and a leading surface, continuous from one of said side surfaces to the other, said leading surface being presented against the stream of air; and each of said cas- 35 ing means having a plurality of longitudinally spaced metallic fins, transverse to said casing means, arranged to present free margins against the stream of air, said margins being spaced away from
  • An electric unit heater comprising: a plurality of electric heating elements; and mounting means for said elements, including a casing in which said elements are disposed; each of said elements having an elongated body portion, each body portion having transverse fin means dis- 45 posed along the length of the body portion and extending laterally from the body portion; said mounting means being constructed and arranged to mount said elements in spaced relation, free to expand longitudinally, said mounting means 50 comprising spaced supporting members each provided with a series of recesses, the recesses of at least one series being in the form of open-end slots, the two series together forming a series of pairs of recesses each pair receiving the body por- 55 tion of one of said elements; and removable means detachably holding said elements in said recesses while leaving said elements free to expand longitudinally.
  • An electric unit heater comprising: a plurality of electric heating elements; and mounting means for said elements, including a casing in which said elements are disposed; each of said elements having a flat, elongated, metal-sheath body portion of the strip heater type, each body portion having transverse fin means disposed along the length of the body portion and extending laterally from the body portion; said mounting means being constructed and arranged to mount said elements edgewise in laterally spaced relation, free to expand longitudinally, said mounting means comprising spaced supporting members each provided with a series of recesses, the recesses of at least one series being in the form of open-end slots, the two series together forming a series of pairs of recesses each pair receiving the body portion of one of said elements; and removable means detachably holding said elements in said recesses while leaving said elements free to expand longitudinally.
  • An electric unit heater comprising: a plurality of electric heating elements; and mounting means for said elements, including a casing in which said elements are disposed; each of said elements having an elongated body portion, each body portion having transverse fin means dis; posed along the length of the body portion and extending laterally from the body portion; said mounting means being constructed and arranged to mount said elements in spaced relation, free to expand longitudinally, said mounting means comprising spaced supporting members each provided with a series of apertures, the two series together forming a series of pairs of apertures each pair receiving the body portion of one of said elements; each of said elements having said fin means constructed and arranged to engage one of said supporting members to support the element longitudinally at one end, and thereby free to expand longitudinally.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Central Heating Systems (AREA)

Description

y 8, 1937. E. 1.. WIEGA ND 2,080,798
AIR CONDITIONING APPARATUS Original Filed May 19, 1935 5 Sheets-Sheet 1 I1 I! if Lnwm 1..s WnaAua ATTOR Y 5 y 8, 1937. E. WIEGAND 2,080,798
AIR CONDITIONING APPARATUS Original Filed May 19, 1955 3 Sheets-Sheet 2 lNVN TOR ATTOR NEYS May 1937- E. L. WIEGAND 2,080,798
AIR CONDITIONING APPARATUS Original Filed May 19, 1953 3 Sheets-Sheet 5 M L-WIGAND 1N VLN 1' OR MMMMW ATTORNJEY5 Patented May 18, 1937 UNITED STATES PATENT O-FFIQE 7 AIR CONDITIONING APPARATUS Original application May 19, 1933, Serial No,
Divided and this application May 18,
1936, Serial No. 80,285. Renewed February 15,
27 Claims.
This invention relates to air conditioning apparatus and has for its principal object the provision of new and improved apparatus of this character.
This application is a division of my copending application 671,878, filed May 19, 1933.
In the drawings accompanying this specification and forming a part of this application, I have shown, for the purpose of illustration, one form which my invention may assume, and in these drawings:
Figure 1 is a vertical sectionalview of the invention, showing parts in elevation,
Figure 2 is a front elevational view of the invention, with portions thereof broken away to disclose the interior construction,
Figure 3 is a fragmentary, enlarged, broken vertical sectional view corresponding substantially to the line 3-3 of Figure 2,
Figure 4 is an enlarged fragmentary perspective view of one portion of the apparatus,
Figure 5 is a rear elevational view of the invention showing one manner of supporting the motor and fan unit,
Figure 6 is a similar view showing a different embodiment of the motor and fan supporting means,
Figure 7 is a side elevational view of a thermally responsive means employed in connection with the invention, and showing the parts in one position,
Figure 8 is a vertical sectional view of the thermally responsive means taken on the line 8-8 of Figure 9, and disclosing the parts in a difierent position,
Figure 9 is a top plan view, partlyin section, of the thermally responsive means shown in Figures 7 and 8, while Figure 10 is a diagrammatic layout of the electrical appliances employed in connection with the invention.
The embodiment of the invention shown in Figures 1 through 5, 7 through 9, and Figure 10, comprises a metallic casing 20, preferaby oblong rectangular in cross-section and open at both ends. Adjacent one end of the casing 20 is disposed a plurality of electrical heating elements 2|, extending transversely across the passage defined by the inner casing wall, and, as best shown in Fig ures 3 and 4, each having an elongated portion 22, oblong rectangular in cross-section, disposed edgewise to the direction of air fiow through the casing 20, comprising a metallic outer casing 23, a heating coil 24, and interposed insulating refractory material 25, the ends of the coil being in well defined directions.
4 36 therebetween, and in the case of the support connected with terminal posts 26 and 21. Arranged along the body portion 22 of each heating element 21, is a plurality of laterally extending fin members 23, each having a central aperture surrounded by a flange 29, and so disposed that 5 the flanges 29 are arranged in overlapping abutting relation, the flns 26 providing large radiating surfaces and operating also to provide air passages therebetween which direct passing air 10 Supporting the heating elements 21 in proper position in the casing 20 are supporting means comprising a support 30 for one set of ends of the heating elements 2 l, and a support 3| for the opposite ends of the heating elements 2|, the supports 30 and 31 preferably being similar, though oppositely disposed, and the same reference characters designate like parts of both. Each of the supports 30 and 31 comprises a pair of end blocks 32, over which is fitted an angular section 33, having a flange 34 welded to one end of the block 32, as at 35, and having a flange 36 welded to the top of the block, and the flange 36 is provided with a plurality of slots 31, each beginning adjacent the corner of the section 33, and extending outwardly and opening at the free edge of the flange 36. Each slot 31 is adapted for the reception of one end of the rectangular body portion 22 of an individual heating element 21, and the body portion 22 of each heating element is maintained in position in each slot 31 by means of a plate 49 detachably secured to the opposite end of each block 32, as by a screw 41 tapped into the block, the plate 40 being provided with an angular flange 42 which lies snug against the edge of the flange 36 and spans the mouths of the slots 31, to close the same, and the plate also cooperates with the section 33, and the blocks 32. to define a hollow formation characteristic of both supports 30 and 31, and within which the 40 projecting ends of the body portions 22 of the heating elements are accommodated. The spaced supporting formations 30 and 3i are tied together by side bars 43 having their ends secured to the blocks 32 by welding or the like, as at 44, and the 45 side bars 43 are secured to the casing 20 by screws 45 threaded into tapped holes 46 extending through the side bars 43 and into the blocks 32. In the case of the support 3i, the heating elements 2| may be inserted laterally into the slots 31, with the flange 36 extending between the adjacent end pair of fins 28, the latter preferably being placed closer together than the remainder of the fins to insure snug reception of the flange a 38 the heating elements 2| may also be inserted laterally into the slots 37, with the end fin of each, indicated at 38, spaced from the flange 36 to allow for expansion of the heating element 2|; the plates 40 afterward being secured in position.
The projecting end portions 41 of the heating elements 2|, housed within the hollow formation of the support 3|, carry contacts 26 and 21, which are connected to bus bars 48 by means of angular connecting members 49, and the bars 48 in turn are connected by conductors 50 and with terminal posts 52 and 53 positioned in a receptacle 54 at the exterior of the housing 20, the manner of electrically connecting the heating elements 2| being hereinafter more particularly pointed out in connection with the de scription of the diagrammatic layout shown in Figure At the outlet of the casing 20 there are provided a plurality of louvers or deflectors 550 pivotally mounted as at 55|, and manually adjustable for intercepting and directing the air issuing from the outlet of the casing 20 as desired.
At the inner side of the bank of heating elements, and within the casing 28, there is mounted a partition 55 having angular flanges 58 secured to the casing wall by bolts 51, and the partition 55 is provided with a central aperture 58 ing a flange 10 secured to the partition 55 by the armature shaft of a motor 80.
As shown in Figure 5 the motor 80 is supported in position with respect to the casing 20, by feet 8| projecting from the central part 82 of the motor, and the feet 6| rest upon the end portions of a plate 63, bearing upon the central portions of a pair of resilient metallic supporting strips 64, the feet 6|, the plate 83, and the central portions of the strips 64 being all clamped together by bolts 85, and the outer opposite end portions of the members 84 diverge with respect to each other and end flanges thereof secured to the casing wall, as by bolts 56. Rubber pads may be interposed between the feet GI and the plate 83 for dampening vibrations.
A somewhat different embodiment of motor mounting is shown in Figure 6, in this case comprising a supporting member having a cradle portion 81 secured by screws to the motor casing, and connected by struts 68 to a ring 59 having a flange 18 secured to the partition 55 by screws 1|.
As best shown in Figure 10, the heating elements 2| are connected in parallel circuits 12, I3, and 74, the circuits 13 and 14 connecting through jumper straps and '16 with the conductors I! and 18, the jumper straps in the positions shown in full lines in Figure 10, rendering the system suitable for single phase operation. The jumper straps I5 and 18 however, may be rearranged, as indicated in dotted lines in Figure 10, to connect with a conductor 19, and thus render the system suitable for threephase operation. The conductors TI, 18 and 19 are adapted to be connected with feed wires through a switch 88. Control mechanism is included in a parallel circuit 8|, comprising a thermostatically controlled switch 82, of any commercial type, operable to make and break the circuit 8| dependent upon the temperature, and operating through any well known type of switch operating mechanism, one of which may include a spring normally urging the blades of the switch 80 to disengaged position, while a solenoid 83, when energized, operates to close and hold closed the switch 80, so that when the thermostatically controlled switch 82 breaks the circuit 8|, the solenoid is de-energized, permitting the spring to disengage the switch 88 and cut off the supply of current to the heating elements 2|. The motor and fan unit may be included in another circuit not affected by the making and breaking of the circuit 8|.
My invention also contemplates the interposition of a safety cut-out device 84, within the control circuit 8|, this device being positioned adjacent the heating elements 2| within the easing 20. As best shown in Figures 1, '7, 8, and 9, the safety thermal cut-out comprises an elongated metallic block 85 secured by bolts to the plate 34 of the supporting formation 8| for the heating elements 2|, and to the opposite sides of the block are clamped resilient contact members 88 and 81, having angular end portions provided with contact points 88, and the member 81 is extended to provide an extension 89, and to the extension 89 is clamped an operating rod 90 extending to the outside of the casing and terminating in an operating knob, each of the contact members 86 and 81 being insulated from the block 85 and from each other by suitable insulating members, and the bolts 9| which clamp the contact members in' position also serve as terminal members 92 for connection with wires forming the circuit 8|. The block 85 is also provided with an offset portion 93 to which is secured a bimetallic thermally responsive element 94, and to the opposite side of the block 85 is secured a resilient latch member 95 having a screw extending laterally therethrough providing an adjustable post 96 which extends between the contact members 85 and 81 and into abutment with the thermally responsive element 94, and beyond the post 98 the latch memher 95 is provided with a laterally extending portion having an engaging face 91 adapted in one position to bear against the extension 88 to hold the contacts 88 in engagement, and also having a beveled surface 88 to facilitate movement of the extension 89 into latching position when the extension 89 is moved by manipulation of the rod 98 to reset the latch after the same has been detached.
Assuming the jumper straps l5 and 18 to be in the position illustrated in full lines in Figure 10, for single phase operation, and the circuit 8| closed, the fan will operate to direct air through the casing 28, and through and into contact with the heating elements 2|, such air emerging between the louvers or deflectors 558. Due to the manner in which the heating elements 2| are arranged in the casing, that is, edgewise with respect to the air stream, and because of the presence of the fins 28 upon the heating elements 2|, passage of the air through the heating elements not only is not unduly obstructed, but the air is directed in well defined paths forwardly from the mouth of the casing and the air so issuing may be more effectively directed where desired through manipulation of the louvers 550; in addition the fins 28 provide extensive radiating surfaces and great efiiciency as will be understood. The heating elements 2| may be operated in concert, as just described, but, if desired, the heating units in the circuits [3 and/or 14 may be cut out temporarily by disconnecting the jumper straps 15 and/or I6.
Automatic control of the heating elements 2| is eilected through operation of the thermostatically controlled switch 82 which interrupts the circuit 8| when the temperature rises beyond a predetermined level, resulting in disconnection of the switch 80, and deenergization of the heating elements 2i. When the temperature falls sumciently to again operate the thermostatically controlled switch, the circuit 8! is again closed, resulting in closing of the switch 80, and energization of whatever heating elements are included in the circuit.
The safety thermal cut-out 84 is located adjacent to the heating coils 2|, and when the temperature rises too high for safety, the safety cut-out operates to interrupt the circuit ill, and deenergizes the heating elements. This operation takes place through deformation of the bimetallic strip 94, which forces the latch 95 outwardly, and causes the contact member 81 to spring away and separate the contact points 88.
The safety cut-out of course deenergizes the circuit 8| until the device is reset by manipulation of the rod 90, which may be pressed inwardly, causing the extension 89 of the contact member 81 to ride along the beveled surface 98 of the latch until the latch springs into position to again hold the points 88 in engagement.
To convert the heater circuit for three phase operation it is only necessary to disconnect the Jumper straps 15 and 16 from communication with the conductors TI and I8, and connect the ends thereof to the third conductor 19, in which case the circuits l3 and 14 are completed through the conductor 19, and the remainder of the apparatus operates in the manner already described.
While I have herein disclosed the preferred embodiment of my invention it will be understood that various changes may be made and details modified, all without departing from the spirit of my invention, or sacrificing the advantages thereof, either those advantages herein above specifically pointed out or any other advantages not specifically pointed out but which nevertheless will be apparent to those skilled in the art. Therefore it will be understood that the disclosure herein is illustrative only, and that my invention is not limited thereto.
I claim: 7
1'. Heating apparatus, comprising: a casing through which air is adapted to be directed; an elongated heating element extending across the passage provided by said casing and adapted to be traversed by air passing through said casing, said heating element having a body portion and a plurality of laterally extending longitudinally spaced fins thereon; and means carried by said casing for holding said heating element in position, said means having a wall slotted for the lateral reception of the body portion of said heating element, with said wall disposed between adjacent fins on said body portion.
2. Heating apparatus, comprising: a casing through which air is adapted to be directed; an elongated heating element extending across the passage provided by said casing and adapted to be traversed by air passing through said casing; and means carried by said casing for holding said heating element in position, said means having a wall provided with an open-ended slot for the reception of the body portion of said heating element; and a member detachably secured in position to close the open end of said slot to maintain said heater in position therein.
3. Heating apparatus, comprising: a casing through which air is adapted to be directed; an elongated heating element extending across the passage provided by said casing and adapted to be traversed by air passing through said casing, said heating element having a body portion and a plurality of laterally extending longitudinally spaced fins thereon; and means carried by said casing for holding said heating element in position, said means having a wall provided with an open-ended slot for the lateral reception of the body portion of said heating element with said wall disposed between adjacent fins on said body portion; and a member detachably secured in position to close the open end of said slot.
4. Heating apparatus, comprising: a casing through which air is adapted to be directed; an elongated electrical heating element extending across the passage provided by said casing and adapted to be traversed by air passing through said casing; means carried by said casing and having walls cooperating with said casing to provide a hollow'formation for the accommodation of the end portion of said heating element; and
electrical connections connected with said heating element and arranged within said hollow formation,
5. Heating apparatus, comprising: a casing through which air is adapted to be directed; a plurality of spaced elongated electrical heating elements extending across the passage provided by said casing and adapted to be traversed by air passing through said casing; means carried by said casing adjacent the opposite ends of said heating elements, and each having walls cooperating with a wall of said casing to provide a hollow formation for the accommodation of the opposite end portions of said heating elements and having connecting members connecting the opposite end portions of said hollow formations to form a supporting frame; and electrical connections connected with said heating elements and arranged within one of said hollow formations.
6. Heating apparatus, comprising: a casing through which air is adapted to be directed; a plurality of elongated electrical heating elements extending across the passage provided by said casing and adapted to be traversed by air passing through said casing; means carried by said casing for securing said heating elements in position, and having walls cooperating with said casing to provide a hollow formation, one of said walls having a plurality of slots for laterally receiving portions of said heating elements.
7. Heating apparatus, comprising: a casing through which air is adapted to be directed; and
an elongated heating element extending across to the stream of air adapted to pass through said casing, said heating element having a plurality of laterally extending, longitudinally spaced fins, providing means for directing the air in its passage through said casing; and means carried by said casing for holding said heating elements in position, said means havinga wall provided with an open-ended slot adapted for the edgewise reception of said heating element, with said wall disposed between adjacent fins on said heating element.
-8. Heating apparatus, comprising: a casing through which air is adapted to be directed; an elongated heating element extending across the passage provided by said casing and adapted to be traversed by air passing through said casing, said heating element having a body portion and a plurality of laterally extending longitudinally spaced fins thereon; and means carried by said casing for holding the opposite ends of said heat- 7 ing element in position, said means adjacent one end of said heating element having a wall provided with an open-ended slot for the reception of the body portion of said heating element with said wall disposed between adjacent fins on said body portion, and a wall adjacent its opposite end provided with a slot for the reception of the opposite end of said heating element, said latter wall being spaced from the nearest adjacent fin to permit expansion of said heatingelement.
9. Heating apparatus, comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; means for supporting said heating means from the top wall of said housing; means for loosely supporting the bottom of said heating means to permit movement incident to expansion and contraction of said heating means; and means for directing air through said housing structure and about said heating means.
10. Heating apparatus, comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; means for supporting said heating means from the top wall of said housing; means for loosely supporting the bottom of said heating means for movement incident to expansion and contraction of said heating means, said means being constructed to limit and guide said movement during such expansion and contraction; and means for directing air through said housing and about said heating means.
11. Heating apparatus, comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; means for supporting said heating means from the top wall of said housing; means for loosely supporting the bottom of said heating means for movement incident to expansion and contraction of said heating means, said means being constructed to limit and guide said movement, and including a slot, and means carried by said heating element slidably accommodated in said slot; and means for directingair through said housing and about said heating means.
12. Heating apparatus, comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; means for supporting said heating means from the top wall of said housing, including a slotted portion, means carried by said heating means projecting through the slot of said slotted portion, and having an abutment resting upon the wall defining said slot, thus to suspend said heating means; means for loosely supporting the bottom of said heating means to permit movement incident to expansion and contraction of said heating means; and means for directing air through said housing and about said heating means.
13. Heating apparatus, comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; means for supporting said heating means from the top wall of said housing, including a slotted portion, means carried by said heating means projecting through the slot of said slotted portion and having an abutment engaging the walls defining said slot, thus to suspend said heating means; means for loosely supporting the bottom of said heating means for movement incident to expansion and contraction of said heating means, said means being constructed to limit and guide said movement during such expansion and contractio::, including a slot, and means carried by said heating element slidably accommodated in said 5101;
and means for directing air through said housing structure and about said heating means.
14. Heating apparatus, comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; means for supporting said heating means from the top wall of said housing; means for loosely supporting the bottom of said heating means for movement incident to expansion and contraction of said heating means, said means being constructed to limit and guide said movement during such expansion and contraction, including a slot, and means carried by said heating element slidably accommodated in said slot; part of said bottom supporting means being removable to permit ready detachment of said heating means therefrom; and means for directing air through said housing structure and about said heating means. 15. Heating apparatus, comprising: a housing structure having a top and bottom wall; heating means disposed within said housing; top supporting means for supporting said heating means from the top wall of said housing, including a slotted portion, means carried by said heating means projecting through the slot of said slotted portion and having an abutment engaging the walls defining said slot, thus to suspend said heating means; bottom supporting means for loosely supporting the bottom of said heating means for movement incident to expansion and contraction of said heating means, said means being constructed to limit and guide said movement during such expansion and contraction, including a slot, and means carried by said heating element slidably accommodated in said slot; said top and bottom supporting means each having a removable part to permit ready removal of said heating means from said housing structure; and means for directing air through said housing structure and about said heating means. 16.1n combination: a housing structure; a heater including a casing, a resistor within said casing, and terminals for said resistor, carried by said casing; said casing, resistor and terminals forming a unit mountable in and removable from said housing structure; and means including a lateral projection on said casing whereby said heater unit is supported by said casing from said housing structure, whereby the supporting strain is put upon said casing, and said terminals are relieved from the supporting strain.
1'7. In combination: a housing structure; a heater including a casing, heating means within said casing; a plurality of laterally extending longitudinally spaced fins on said casing; and
means whereby said heater is supported by at least one of said fins from said housing structure.
18. Heating apparatus, comprising: a housing providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements disposed in said passage, so constructed and arranged that said stream of air is adapted to abstract heat from said heat ing elements; each heating element constituting a unit, so contructed and arranged that each unit is individually mountable in and removable from said housing; and each unit including a plurality of laterally extending longitudinally spaced metallic fins, and heat generating means, individual to each unit.
19. Heating apparatus, comprising: a housing providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements disposed in said passage, so constructed and arranged that said stream of air is adapted to abstract heat from said heating elements; each heating element constituting a unit, so constructed and arranged that each unit is individually mountable in and 5 removable'from said housing; and each unit including metallic casing means, and a plurality of laterally extending longitudinally spaced metallic fins on each casing means, and heat generating means, all individual to each unit.
20. Heating apparatus, comprising: a housing providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements disposed in said passage, so constructed and arranged that said stream of air is adapted to abstract heat from said heating elements; each heating element constituting a unit, so constructed and arranged that each unit is individually mountable in and removable from said housing; and each unit including metallic casing means having a plurality of laterally extending longitudinally spaced metallic fins, and an electrical resistor embedded in a mass of refractory insulating material in said casing means.
5 21. Heating apparatus, comprising: a housing providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements extending transversely across said passage, constructed and arranged to be traversed by said stream of air; each of said heating elements including metallic casing means and an electrical resistor embedded in a mass of refractory insulating material in said casing means; each of said casing means being constructed oblong in cross-section and arranged edgewise to the stream of air passing through said housing, and presenting the major areas thereof parallel to the general direction of movement of said stream so as to increase the effective areas traversed by said air; and each of said casing means having a plurality of laterally extending longitudinally spaced metallic fins, said fins having continuous surfaces, transverse to said casing means, continuously surrounding said casing means.
22. Heating apparatus, comprising: a housing providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements disposed transversely across said passage, so constructed and arranged that said stream of air is adapted to abstract heat from said heating elements; each of said elements including metallic casing means containing an electrical resistor embedded in amass of refractory insulat- 65 ing material in said casing means; the cross-sectional shape of each of said casing means being so constructed and arranged that the dead air space, on the surface of said casing means trailing with respect to said stream, is reduced to thereby increase the area of contact between said stream and said casing means; and each of said casing means having a plurality of laterally ex tending longitudinally spaced metallic fins, said fins having continuous surfaces, transverse to said casing means, continuously surrounding said casing means.
23. Heating apparatus, comprising: a housing providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements extending transversely across said passage, constructed and arranged to be traversed by said stream of air; each of said heating elements including metallic casing means and an electrical resistor embedded in a mass of re- 7 fractory insulating material in said casing means;
each of said casing means being constructed oblong in cross-section and having side surfaces, and a leading surface, continuous from one of said side surfaces to the other, said leading surface being presented against the stream of air passing 5 through said housing, and said side surfaces being presented parallel to the general direction of movement of the stream so as to increase the effective areas traversed by said air; and each of said casing means having a plurality of longil0 tudinally spaced metallic fins, transverse to said casing means, arranged to present free margins against the stream of air, said margins being spaced away from said leading surface.
24. Heating apparatus, comprising: a housing 15 providing a passage through which a stream of air is adapted to be directed; at least two elongated heating elements disposed transversely across said passage, so constructed and arranged that said stream of air is adapted to abstract heat from said 20 heating elements; each of said elements including metallic casing means containing an electrical resistor embedded in a mass of refractory insulating material in said casing means; the crosssectional shape of each of said casing means being so constructed and arranged that the dead air space, on the surface of said casing means trailing with respect to the stream of air, is reduced to thereby increase the area of contact between said stream and said casing means, said casing means having side surfaces, and a leading surface, continuous from one of said side surfaces to the other, said leading surface being presented against the stream of air; and each of said cas- 35 ing means having a plurality of longitudinally spaced metallic fins, transverse to said casing means, arranged to present free margins against the stream of air, said margins being spaced away from said leading surface.
25. An electric unit heater, comprising: a plurality of electric heating elements; and mounting means for said elements, including a casing in which said elements are disposed; each of said elements having an elongated body portion, each body portion having transverse fin means dis- 45 posed along the length of the body portion and extending laterally from the body portion; said mounting means being constructed and arranged to mount said elements in spaced relation, free to expand longitudinally, said mounting means 50 comprising spaced supporting members each provided with a series of recesses, the recesses of at least one series being in the form of open-end slots, the two series together forming a series of pairs of recesses each pair receiving the body por- 55 tion of one of said elements; and removable means detachably holding said elements in said recesses while leaving said elements free to expand longitudinally.
26. An electric unit heater, comprising: a plurality of electric heating elements; and mounting means for said elements, including a casing in which said elements are disposed; each of said elements having a flat, elongated, metal-sheath body portion of the strip heater type, each body portion having transverse fin means disposed along the length of the body portion and extending laterally from the body portion; said mounting means being constructed and arranged to mount said elements edgewise in laterally spaced relation, free to expand longitudinally, said mounting means comprising spaced supporting members each provided with a series of recesses, the recesses of at least one series being in the form of open-end slots, the two series together forming a series of pairs of recesses each pair receiving the body portion of one of said elements; and removable means detachably holding said elements in said recesses while leaving said elements free to expand longitudinally.
27. An electric unit heater, comprising: a plurality of electric heating elements; and mounting means for said elements, including a casing in which said elements are disposed; each of said elements having an elongated body portion, each body portion having transverse fin means dis; posed along the length of the body portion and extending laterally from the body portion; said mounting means being constructed and arranged to mount said elements in spaced relation, free to expand longitudinally, said mounting means comprising spaced supporting members each provided with a series of apertures, the two series together forming a series of pairs of apertures each pair receiving the body portion of one of said elements; each of said elements having said fin means constructed and arranged to engage one of said supporting members to support the element longitudinally at one end, and thereby free to expand longitudinally.
EDWIN L. WIEGAND.
CERTIFICATE OF CORRECTION.
Patent No. 2,080,798.
EDtIN L.
May 18, 1957.
WIEGANDQ It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:
Page 2,
first column, line 29, strike out the syllable and words "ing a flange 70 posed a fan 59,
the case in the Patent Office.
may conform to the record Signed and sealed this 27th day of July, A. D. 1937.
(Seal) I-lenry Van Arsdale instead within which is dis L tters Patent should be read Acting Commissioner of Patents.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3176117A (en) * 1961-03-09 1965-03-30 Berko Electric Mfg Corp Electric space heater unit
US3422249A (en) * 1965-04-13 1969-01-14 Crane Co Safety device for an electric hot water baseboard
US20120328270A1 (en) * 2011-06-21 2012-12-27 Arjan Dykman Explosion Proof Forced Air Electric Heater

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3176117A (en) * 1961-03-09 1965-03-30 Berko Electric Mfg Corp Electric space heater unit
US3422249A (en) * 1965-04-13 1969-01-14 Crane Co Safety device for an electric hot water baseboard
US20120328270A1 (en) * 2011-06-21 2012-12-27 Arjan Dykman Explosion Proof Forced Air Electric Heater
US8755678B2 (en) * 2011-06-21 2014-06-17 Arjan Dykman Explosion proof forced air electric heater

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