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US2001834A - Vertical unit heater - Google Patents

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US2001834A
US2001834A US458299A US45829930A US2001834A US 2001834 A US2001834 A US 2001834A US 458299 A US458299 A US 458299A US 45829930 A US45829930 A US 45829930A US 2001834 A US2001834 A US 2001834A
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air
casing
discharge
conduits
hot air
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US458299A
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Clifford C Carson
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28DHEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D21/00Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
    • F28D21/0001Recuperative heat exchangers
    • F28D21/0003Recuperative heat exchangers the heat being recuperated from exhaust gases
    • F28D21/0005Recuperative heat exchangers the heat being recuperated from exhaust gases for domestic or space-heating systems
    • F28D21/0008Air heaters

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  • This invention relates to unit heaters of the type especially adapted for heating factory'buildings and the like and, among other objects, aims to provide an improved vertical, suspension type heater having provision for discharging a confining curtain or stream of air above the heated air so asto prevent the heated airfrom rising above the breathing line before it gives up a substantial portion of its heat.
  • Fig. 1 is a side elevation; partly in" section, showing a suspension heater embodying the in vention'; Q r Fig; 2is abottomf plan View; and
  • Fig. 13' is' a sectional view' taken on the line I an ordinary tubular heater unit 2 such as is 40
  • the heater there shown is 'similar'in many respects to that shown in my aforesaid application, Ser. NO. 458,300," filed May "31, 1930.
  • 'It' is adapted: to be suspended from roof joists or supported on columns at'any' desired height above the floor where it does not take up any valuable floor space and is adaptedito heat the building.
  • the casing I0 is shownas I having a transversehorizontal partition 20 to which the fan discharge ducts or outlets H are connected to deliver air into a heating chamber or'compartment 2 l
  • the lower end of the casing has an end wall 22 and a vertical partition 23 is l shown as being connected to the partition 20 and the end wall 22 providing the front wall oi the heating chamber.
  • This construction provides an insulatin dead air chamber housing the byfpass conduits lfi so that the relatively cold air passing through them will not absorb heat from the heating chamber.
  • heating chamber 2 I there is shown usually'heated by steam or hot water; but it to be understood that the source of heat is a matter "of selection; Obviously, a direct fired heater utilizing fluid fuelmay be employed. In any event,
  • the arrangement is suclrthat the air passing through the chamber is raised to the desiredtemperature before it is'discharged into the space to beheated.
  • the heated air is discharged downwardly from the lower end of the heating chamber through discharge conduits 25 directed at an angle to the horizontal, the inclination depending on the size of the building and theheight of the discharge orifices above the floor. I-lerein, theyare'inclined at approximately 45 merely for illustration purposes.
  • Each conduit preferably has a division plate or partition 26 to direct the air at a substantially constant velocity throughout the height of the outlet orifice; otherwise, the air would discharge at the greatest velocity near the bottom of the outlet orifice.
  • the by-passed relatively cold air is discharged through wide fiat nozzles 21 connected to the lower ends of the conduits l6 and preferably arranged immediately above the conduits 25 so as to discharge curtains of air at high velocities substantially parallel with the issuing streams of hot air.
  • the velocity ratios depend upon the size of the building and other variable. factors. In some instances, theratio should be about two to one. I i
  • the nozzles 2'! preferably have adjustable Venturi blades 28 intheir mouths so as to vary the angle of discharge and prevent the curtain streams from spreading vertically.
  • the idea is to so regulate the velocity and direction of discharge of the curtain streams as to cause'them to flatten out horizontally at or near the breathing line and prevent penetration of the heated air before it gives up a substantial portion of its heat below the breathing line. Without the confining stream or streams of air,
  • Venturi vanes 28' may be adjusted to restrict the flow of air through the nozzles 21, an adjustable damper 29. is shown in each of the cold air conduits l5 so that the volume and velocity of the air passing through the conduits may be widely varied to suit the particular requirements. Thus, the temperature difference and relative velocities of the hot and cold air streams may be changed at will. Hence, a heater of this type may be quickly adjusted to operate economically in any ordinary building or room. 7 From'the foregoing description, it will be seen that unit heaters embodying this invention can be manufactured very economically and installed very quickly. They are very compact i'n design and are far more efficient than the old and well known types of suspended heaters. The high velocity streams of air produce more uniform distribution of the heatedair and maintain approximately constant temperatures of wide areas. Moreover, this type of heater will reduce the normal temperature rise per foot of height and thus reduce the normal heat losses through the roof of a building. V
  • a unit heater of the class described com.- prising in combination, a substantially vertical, rectangular casing having an open upper end; a heating chamber in the lower portion of the casing; a heat exchanger in the heating chamber; a plurality of fans in the open end of said casing and connected to deliver air through said chamber; a plurality of hotair discharge con.- duits, one for each.fan,-at the lower end ofisaid casing arranged to directthe air downwardly at one for each fan, at the lower end of said casing arrangedto direct the air at an angle to the horizontal; by-pass conduits connected to said fans; and nozzles at the ends of said by-pass conduits arranged to discharge curtains of air at high velocity above the discharging hot air.
  • a unitheater of the suspension type comprising, in combination, a substantially vertical casing; a heating chamber in the lower portion of said casing; heating means in said chamber; a plurality of centrifugal fans adjacent to the upper end of the casing having discharge outlets connected to said heating chamber; a plurality of hot air discharge outlets, one for eachfan, connected to the lower end of said casing and shaped to direct the air at an angle to the horizontal; by-pass conduits connected to said fans and passing through said casing at one side of the heating chamber; and relatively wide dis charge nozzles at the lower ends of said by-pass conduits adjacent to said hot air conduits adapted to discharge curtains of relatively cold air at high velocity above and substantially parallel with the discharging hot air. 4.
  • a unit heater of the class described comprising, in combination, a substantially vertical casing having an open upper end and a heating chamber in its lower end portion; a tubular heat exchanger in said heating chamber; means in the open end of said casing to create a blast of air through said heating chamber; a discharge conduit for the heated air at the lower end of said casing connected to direct the air downwardly at an angle to the horizontal; and means to dis? charge a separate stream of relatively cool air adjacent to the discharging hot air whereby to confine the hot air to circulate in the lower portion of the space to be heated until it has given up a substantial portion of its heat.
  • a unit heater of the class described com.- prisingfin combination a substantially vertical casing; means to suspend the casing above the space to be heated; a heating chamber within the casing; a tubular heat exchanger withinrthe chamber; a plurality of centrifugal fans adjacent to the upper end of said casing and connected to discharge air through said heating chamber; a motor supported on said casing and connected to drive all of said fans; a plurality of hot air discharge conduits, one for each fan, connected to the lower end of said casing and arranged to die rect the hot air at an angle to the horizontal; by-pass conduits connected to said fans and passing through the casing on the outside of said heating chamber; relatively fiat nozzles connected to said by-pa'ss conduits adjacent to the hot air discharge conduits; adjustable Venturi vanes in the mouths of said nozzles; and means to vary the volume of air passing through said by-pass conduits.
  • prising in combination, a substantially vertical casing; means to support'the casing above the space to be heated; a horizontal partition within the casing below the upper end thereof and providing a heating chamber in the lower portion of the casing; a plurality of centrifugal fans arranged adjacent to the upper end of the casing; outlet conduits for the fans connected to said partition and discharging into the heating chamber; a heat exchanger mounted in said heating chamber; a plurality of hot air discharge conduits, one for each fan, connected to the lower end of said casing and arranged to discharge hot air at an angle to the horizontal; by-pass conduits connected to said fans and arranged to deliver air at a relatively high velocity; and a plurality of relatively wide discharge nozzles connected to said by-pass conduits adjacent to the hot air conduits and arranged to discharge confining curtains of relatively cold air at high velocity above the discharging hot air whereby to confine the hot air to circulate in the lower portion of the space to be heated until it has given up a substantial portion of its heat.
  • a unit heater of the suspension type comprising, in combination, a casing, heating means Within the casing; a fan connected to create a current of air through the casing; a conduit connected to the fan and arranged to by-pass a portion of the air at a relatively high velocity around the heating means; a hot air discharge conduit connected to the casing and directed downwardly at an angle to the horizontal; and
  • a unit heater of the suspension type comprising, in combination, a casing; heating means within the casing; a fan connected to create a current of air through the casing; a conduit connected to the fan and arranged to by-pass a portion of the air at a relatively high velocity around the heating means; a hot air discharge conduit connected to the casing and directed downwardly at an angle to the horizontal; and a wide relatively fiat nozzle connected to the bypass conduit above the hot air discharge conduit andadapted to discharge a confining curtain of air at high velocity above the hot air.
  • a unit heater of the suspension type comprising, in combination, a casing; tubular heat exchanging elements within the casing; a fan connected to create a current of air through the casing; a conduit connected to the fan and arranged to by-pass a portion of the air at a relatively high velocity around the heat exchanging elements; a hot air discharge conduit connected to the casing and directed downwardly at an angle to the horizontal; and a discharge nozzle for the by-passed air above the hot air discharge conduit arranged to discharge a confining stream of air above the hot air.
  • a unit heater of the class described comprising, in combination, an elongated substantially rectangular casing open at one end; a centrifugal fan supported in the open end and connected to discharge through the casing; heating means near the other end of the casing; a discharge conduit for the heated air; a wide discharge nozzle above the hot air conduit; and means to deliver air at a relatively high velocity through said nozzle.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Air-Conditioning Room Units, And Self-Contained Units In General (AREA)

Description

May 21, 1935. c. c. CARSON 'VERTICAL UNIT HEATER Filed Ma 31, 1930 2 Sheets-Sheet 1 ATTORNEYS May 21, 1935. c. c. CARSON VERTICAL UNIT HEATER Filed May 51, 1930 2 Sheets-Sheet 2 Patented May 21, 1935 PATENT OFFICE VERTICAL UNIT HEATER Cliflo'rd C. Carson, Chicago, Ill. Application May 31, 1930, Serial N o. 458,299
11 Claims.
This invention relates to unit heaters of the type especially adapted for heating factory'buildings and the like and, among other objects, aims to provide an improved vertical, suspension type heater having provision for discharging a confining curtain or stream of air above the heated air so asto prevent the heated airfrom rising above the breathing line before it gives up a substantial portion of its heat. i
This application is intimately related to my co-pending application, Ser. No. 458,300, filed May 31, 1930, and also involves the method broadly claimed in my co -pending application, Ser. No. 308,681, filed Sept. 27, 1928, which 15' has matured into Patent No. 1,820,893 granted Aug. 25, 1931. this invention is the vertical arrangement of the suspended heater casing whereby the intake air is taken from the upper part of the room" or 20, building where the temperature is higher than is the temperature near the floor level. More over, the temperatureof the confining stream or. curtain of high velocity air is maintained at a somewhat higher temperature than wouldbe the floor level Furthermore, the arrangement is such that room air will'cir'culate' upwardly through the casing in the'eve'nt that the fan is stoppedand thereby set up a natural circulation of the air. I
Other aims and advantages of the invention will appear iuthe specification, when considered in connection with the" accompanying drawings, wherein: V
Fig. 1 is a side elevation; partly in" section, showing a suspension heater embodying the in vention'; Q r Fig; 2is abottomf plan View; and
1 Fig. 13'is' a sectional view' taken on the line I an ordinary tubular heater unit 2 such as is 40 Referring particularly to the drawings, the heater there shown is 'similar'in many respects to that shown in my aforesaid application, Ser. NO. 458,300," filed May "31, 1930. 'It' is adapted: to be suspended from roof joists or supported on columns at'any' desired height above the floor where it does not take up any valuable floor space and is adaptedito heat the building. or room very largely 'bydi'splacemen't hot air currents dis- 1 One of the important features of maintained if the intake air were admitted near on a shaft l2 journale'd in opposite sides of the casing are arranged in the upper open end so as to take air from the upper portion of the building or room and blow it downwardly through the casing to beheated' Herein, three fans H are 5 mounted in spaced housings I 3 each having a: 7 double scroll From each fan housing air is delivered through a discharge outlet l4 intothe heater casing and a small discharge duct l5 connec'ted to a vertical by-p'ass conduit [6 arranged 10 adjacent to the front wall of the casing. The, arrangement is such that the .air delivered through the by-pass conduits is not heated and travels ata muchhigher velocity than the currents of air delivered through the casing.
Referring to Fig. 1, intake airis admitted to the respective fans through ordinary inlet cones IT in the opposite end walls of the fan housings so that air is sucked into the fans practically throughout the open end of the heater casing, In this instance, the fan shaft l2, projects through one side wall of the casing l0 and is driven by a motor it supported on a suitable bracket or shelf I 9 which is conveniently secured to the outside wall of the casing.
Referring to'Fig. 3, the casing I0 is shownas I having a transversehorizontal partition 20 to which the fan discharge ducts or outlets H are connected to deliver air into a heating chamber or'compartment 2 l The lower end of the casing has an end wall 22 and a vertical partition 23 is l shown as being connected to the partition 20 and the end wall 22 providing the front wall oi the heating chamber. This construction provides an insulatin dead air chamber housing the byfpass conduits lfi so that the relatively cold air passing through them will not absorb heat from the heating chamber.
Within the heating chamber 2 I, there is shown usually'heated by steam or hot water; but it to be understood that the source of heat is a matter "of selection; Obviously, a direct fired heater utilizing fluid fuelmay be employed. In any event,
the arrangement is suclrthat the air passing through the chamber is raised to the desiredtemperature before it is'discharged into the space to beheated. h
Further referring to Fig. 3, the heated air is discharged downwardly from the lower end of the heating chamber through discharge conduits 25 directed at an angle to the horizontal, the inclination depending on the size of the building and theheight of the discharge orifices above the floor. I-lerein, theyare'inclined at approximately 45 merely for illustration purposes. Each conduit preferably has a division plate or partition 26 to direct the air at a substantially constant velocity throughout the height of the outlet orifice; otherwise, the air would discharge at the greatest velocity near the bottom of the outlet orifice. The by-passed relatively cold air is discharged through wide fiat nozzles 21 connected to the lower ends of the conduits l6 and preferably arranged immediately above the conduits 25 so as to discharge curtains of air at high velocities substantially parallel with the issuing streams of hot air. The velocity ratios depend upon the size of the building and other variable. factors. In some instances, theratio should be about two to one. I i
As disclosed in my aforesaid application, Ser.
- No. 458,300, filed May 31, 1930, the nozzles 2'! preferably have adjustable Venturi blades 28 intheir mouths so as to vary the angle of discharge and prevent the curtain streams from spreading vertically. The idea is to so regulate the velocity and direction of discharge of the curtain streams as to cause'them to flatten out horizontally at or near the breathing line and prevent penetration of the heated air before it gives up a substantial portion of its heat below the breathing line. Without the confining stream or streams of air,
the induced air currents set up at the intake end 30' of the heater casing would promote rapid rise of the hot air by setting up continuous circulation from the discharge end back toward the intake end. I 7
While the Venturi vanes 28' may be adjusted to restrict the flow of air through the nozzles 21, an adjustable damper 29. is shown in each of the cold air conduits l5 so that the volume and velocity of the air passing through the conduits may be widely varied to suit the particular requirements. Thus, the temperature difference and relative velocities of the hot and cold air streams may be changed at will. Hence, a heater of this type may be quickly adjusted to operate economically in any ordinary building or room. 7 From'the foregoing description, it will be seen that unit heaters embodying this invention can be manufactured very economically and installed very quickly. They are very compact i'n design and are far more efficient than the old and well known types of suspended heaters. The high velocity streams of air produce more uniform distribution of the heatedair and maintain approximately constant temperatures of wide areas. Moreover, this type of heater will reduce the normal temperature rise per foot of height and thus reduce the normal heat losses through the roof of a building. V
Obviously, the present invention is not restricted to the particular embodiment thereof herein shownand. described. Moreover, it is not indise pensable that all the features of the invention be used conjointly, since they may be employed advantageously in variouscombinations and subcombinations.
What is claimed is:
v 1. A unit heater of the class described com.- prising, in combination, a substantially vertical, rectangular casing having an open upper end; a heating chamber in the lower portion of the casing; a heat exchanger in the heating chamber; a plurality of fans in the open end of said casing and connected to deliver air through said chamber; a plurality of hotair discharge con.- duits, one for each.fan,-at the lower end ofisaid casing arranged to directthe air downwardly at one for each fan, at the lower end of said casing arrangedto direct the air at an angle to the horizontal; by-pass conduits connected to said fans; and nozzles at the ends of said by-pass conduits arranged to discharge curtains of air at high velocity above the discharging hot air.
3. A unitheater of the suspension type comprising, in combination, a substantially vertical casing; a heating chamber in the lower portion of said casing; heating means in said chamber; a plurality of centrifugal fans adjacent to the upper end of the casing having discharge outlets connected to said heating chamber; a plurality of hot air discharge outlets, one for eachfan, connected to the lower end of said casing and shaped to direct the air at an angle to the horizontal; by-pass conduits connected to said fans and passing through said casing at one side of the heating chamber; and relatively wide dis charge nozzles at the lower ends of said by-pass conduits adjacent to said hot air conduits adapted to discharge curtains of relatively cold air at high velocity above and substantially parallel with the discharging hot air. 4. A unit heater of the class described comprising, in combination, a substantially vertical casing having an open upper end and a heating chamber in its lower end portion; a tubular heat exchanger in said heating chamber; means in the open end of said casing to create a blast of air through said heating chamber; a discharge conduit for the heated air at the lower end of said casing connected to direct the air downwardly at an angle to the horizontal; and means to dis? charge a separate stream of relatively cool air adjacent to the discharging hot air whereby to confine the hot air to circulate in the lower portion of the space to be heated until it has given up a substantial portion of its heat.
5. A unit heater of the class described com.- prisingfin combination, a substantially vertical casing; means to suspend the casing above the space to be heated; a heating chamber within the casing; a tubular heat exchanger withinrthe chamber; a plurality of centrifugal fans adjacent to the upper end of said casing and connected to discharge air through said heating chamber; a motor supported on said casing and connected to drive all of said fans; a plurality of hot air discharge conduits, one for each fan, connected to the lower end of said casing and arranged to die rect the hot air at an angle to the horizontal; by-pass conduits connected to said fans and passing through the casing on the outside of said heating chamber; relatively fiat nozzles connected to said by-pa'ss conduits adjacent to the hot air discharge conduits; adjustable Venturi vanes in the mouths of said nozzles; and means to vary the volume of air passing through said by-pass conduits.
prising, in combination, a substantially vertical casing; means to support'the casing above the space to be heated; a horizontal partition within the casing below the upper end thereof and providing a heating chamber in the lower portion of the casing; a plurality of centrifugal fans arranged adjacent to the upper end of the casing; outlet conduits for the fans connected to said partition and discharging into the heating chamber; a heat exchanger mounted in said heating chamber; a plurality of hot air discharge conduits, one for each fan, connected to the lower end of said casing and arranged to discharge hot air at an angle to the horizontal; by-pass conduits connected to said fans and arranged to deliver air at a relatively high velocity; and a plurality of relatively wide discharge nozzles connected to said by-pass conduits adjacent to the hot air conduits and arranged to discharge confining curtains of relatively cold air at high velocity above the discharging hot air whereby to confine the hot air to circulate in the lower portion of the space to be heated until it has given up a substantial portion of its heat.
7.'A unit heater of the suspension type comprising, in combination, a casing, heating means Within the casing; a fan connected to create a current of air through the casing; a conduit connected to the fan and arranged to by-pass a portion of the air at a relatively high velocity around the heating means; a hot air discharge conduit connected to the casing and directed downwardly at an angle to the horizontal; and
j a discharge nozzle for the by-passed air above a discharge conduit for the by-passed air above and adjacent to the hot air conduit and shaped to discharge a relatively thin curtain of air at high velocity above the discharging heated air so as to confine the heated air to circulate in the lower portion of the space to be heated until it gives up a substantial portion of its heat.
9. A unit heater of the suspension type comprising, in combination, a casing; heating means within the casing; a fan connected to create a current of air through the casing; a conduit connected to the fan and arranged to by-pass a portion of the air at a relatively high velocity around the heating means; a hot air discharge conduit connected to the casing and directed downwardly at an angle to the horizontal; and a wide relatively fiat nozzle connected to the bypass conduit above the hot air discharge conduit andadapted to discharge a confining curtain of air at high velocity above the hot air.
10. A unit heater of the suspension type comprising, in combination, a casing; tubular heat exchanging elements within the casing; a fan connected to create a current of air through the casing; a conduit connected to the fan and arranged to by-pass a portion of the air at a relatively high velocity around the heat exchanging elements; a hot air discharge conduit connected to the casing and directed downwardly at an angle to the horizontal; and a discharge nozzle for the by-passed air above the hot air discharge conduit arranged to discharge a confining stream of air above the hot air.
1.1. A unit heater of the class described comprising, in combination, an elongated substantially rectangular casing open at one end; a centrifugal fan supported in the open end and connected to discharge through the casing; heating means near the other end of the casing; a discharge conduit for the heated air; a wide discharge nozzle above the hot air conduit; and means to deliver air at a relatively high velocity through said nozzle.
CLIFFORD C. CARSON.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2894728A (en) * 1957-02-06 1959-07-14 Trane Co Multi-zone air conditioning unit
US3394755A (en) * 1967-02-06 1968-07-30 Conditionaire Australia Pty Lt Air screen creating-air conditioning apparatus
US20130248144A1 (en) * 2012-03-26 2013-09-26 Bor-Haw Chang Fan module

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2894728A (en) * 1957-02-06 1959-07-14 Trane Co Multi-zone air conditioning unit
US3394755A (en) * 1967-02-06 1968-07-30 Conditionaire Australia Pty Lt Air screen creating-air conditioning apparatus
US20130248144A1 (en) * 2012-03-26 2013-09-26 Bor-Haw Chang Fan module

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