US2551708A - Humidifier - Google Patents

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US2551708A
US2551708A US51287A US5128748A US2551708A US 2551708 A US2551708 A US 2551708A US 51287 A US51287 A US 51287A US 5128748 A US5128748 A US 5128748A US 2551708 A US2551708 A US 2551708A
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steam
radiator
humidifier
condensate
receptacle
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US51287A
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Gerald W Skilbeck
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24DDOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
    • F24D19/00Details
    • F24D19/08Arrangements for drainage, venting or aerating
    • F24D19/081Arrangements for drainage, venting or aerating for steam heating systems
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F6/00Air-humidification, e.g. cooling by humidification
    • F24F6/12Air-humidification, e.g. cooling by humidification by forming water dispersions in the air

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  • This invention relates to humidifiers and refers more particularly to humidifiers for use with steam heating systems.
  • a humidifying unit of the type here concerned forms the subject matter of Patent No. 2,395,512 issued to Gerald W. Skilbeck, February 1946 and comprises a humidifying receptacle in the nature of a hollow shell having a side inlet connected with a steam radiator or riser to be plied with steam therefrom and having an exhaust port in its top to enable steam to escape from the receptacle to the atmosphere.
  • the humidify ing receptacle is preferably located close to tlr source of steam so as to be in a zone of relatively high temperature, but condensation of steam entering the humidifying receptacle nevertheless inevitably results.
  • the condensate formed in the humidifying receptacle is returned to the system, and the return oi the condensate either to the steam radiator or the riser to which the humidifier is connected has hitherto constituted a difficult problem.
  • the difliculty of returning the condensate to the steam system arises from the fact that the escape of steam through the exhaust port of the humidifier causes a lower pressure to obtain in the humidifier receptacle than in the steam radiator or riser to which the humidifier is connected, so that the condensate must be delivered from a low pressure zone to a zone of higher pressure.
  • the present invention has as its main object the provision of a highly improved manner of effecting return to the steam system of the condensate formed in a. humidifier of the character described.
  • this invention has as its object the provision of an improved manner of installing a humidifying device on a steam radiator or the like, which is characterized by the fact that the humidifier is connected between the source of steam and the radiator so that the pressure in the humidifying receptacle is maintained higher than that obtaining in the radiator, whereby the steam pressure in the humidifying receptacle is employed to return the condensate to the steam system.
  • Still another object of this invention resides in the provision of air conditioning means for use with steam radiators and the like by which the temperature and humidity of a space being heated may be accurately and automatically controlled.
  • a further object of this invention resides in the provision of an air conditioning means, for use with steam heating systems, wherein a humidifying unit of the character described is connected between the source of steam and a steam radiator to inject steam into the atmosphere, and wherein an electrically operated valve controlled by a thermostat in the space being heated governs the flow of steam to the humidifying receptacle and consequently to the steam radiator.
  • FIG. 2 is an enlarged detail view of the humidifying receptacle and its connection to the steam radiator, portions being broken away and shown in section to illustrate interior details of construction;
  • FIG. 3 is a slightly modified form of the invention illustrating the manner in which the supply of steam to the humidifier receptacle and the radiator may be automatically controlled by means of an electrically operated valve in the steam supply line-ahead of the humidifier.
  • the numeral 5 represents a conventional steam heating radiator which, as is customary, comprises a number of spaced: apart vertical radiator sections or flanges communicating at their upper and lower ends.
  • the top of one end section 6 is customarily connected with a source of steam under pressure through a steam supply line I having a valve 8 therein to control the flow of steam into the radiator.
  • the opposite end section 9 has a discharge pipe IO connected to its lower end to return the condensate to the steam system.
  • the valve 8 in the steam supply line 1 is preferably maintained in closed position, and an inlet duct I2 is connected between the humidifying device and the steam supply line ahead of the valve 8, as shown, so that steam from the supply line flows into the interior of the humidifying device.
  • the humidifying device comprises an outer tubularshell l3 having a bored fitting l4 on its side wall medially of its ends providing a side inlet l5 for the shell through which steam from the supply line enters the same.
  • An exhaust port IS in' the upper end of the shell allows part of the steam admitted into the interior of the shell-to escape into the atmosphere, to thus increase the vapor content thereof.
  • the humidifying device per se forms no part of the instant invention, and for a more complete disclosure thereof, reference is had to the aforementioned Patent No. 2,395,512.
  • the humidifying device has an inner cup-like receptacle l'i fixed in its upper end and separating the exhaust port Hi from the interior of the shell.
  • the interior of the shell is communicated with the inside of the cup-like inner receptacle by means of a port I 8 in the bottom wall of the inner receptacle which may be adjustably restricted or even closed by means of a ball check I9.
  • An adjusting screw 20 extends down into the inner receptacle from the top of the shell and has its inner end disposed in the chamber for the ball check to limit the extent to which the ball may be lifted off its seat by steam pressure Within the shell. Consequently, the amount of steam which enters the inner receptacle for discharge through the exhaust port Hi to the atmosphere may be readily controlled by the screw 20'.
  • connected with the bottom of the shell l3 connects the humidifier with the steam radiator through a metering valve 22. While the metering valve may be directly incorporated in the discharge line 2i in the present case it is shownas a needle valve provided with a side inlet 23 to. which the discharge line is attached, and has its outlet 24 threaded into the end radiator section 6 at the lower portion thereof.
  • the metering valve 22 may be employed to regulate the amount of steam admitted into the radiator. Another important function of the metering valve is to assure the maintenance of av higher pressure in the humidifier unit than in the interior of the steam radiator so that the condensate formed within the interior of the humidifier l i may either fiow by gravity through the discharge line 2
  • the metering valve provides, in effect, an adjustably restricted orifice at the steam inlet of the radiator, and that while sufiicient steam may be caused to flow through the metering valve into the radiator for the proper heating of the space in which the radiator is located durin the coldest weather conditions, the valve also enables the flow of steam into the radiator to be controlled or minimized to the extent avoiding overheating during mild weather conditions.
  • the metering valve may be only slightly opened to allow one or two of the first sections or flanges of the radiator to be heated.
  • the pressure within the steam radiator may be held to an extremely low value only slightly above atmospheric pressure, eliminating the need for traps or the like in the outlet line H] leading from the radiator.
  • the manual control valve 8 may be opened so that the humidifying device I l is bypassed. After all of the sections of the radiator have been supplied with steam in thi manner, however, the valve 8 preferably is again closed and the flow of steam to the radiator controlled by means of the needle valve 22 to avoid overheating of the space in which the radiator is located.
  • the installation may operate with the same degree of efiiciency without the by-pass or control valve 8, in which case the steam supply line would connect only with the humidifying receptacle through the inlet duct [2; and all steam admitted into the radiator would first have to pass through the humidifier, assuring positive return of condensate in the humidifier to the system.
  • the supply of steam to the humidifying device and consequently to the steam radiator 5 may be automatically controlled by a room thermostat, not shown, in which case a solenoid valve 26 operated by the thermostat is incorporated in the supply line 1 ahead of the humidifying device H. In thi manner the temperature as well as the humidity of the room or other space being heated by the radiator may be accurately controlled.
  • a heat exchanger a humidifying unit having an exhaust port through which Water vapor may escape to the atmosphere, and including means defining a chamber into which steam is initially admitted to the unit and in which condensate forms; a steam supplying line connected with said chamber to supply steam to the interior thereof; duct means connecting between the bottom of said chamber and the heat exchanger for conducting steam delivered to said chamber along with condensate formed therein into the heat exchanger, said duct means connecting the heat exchanger with the supply line through said chamber; a duct connected between the steam supply line and the heat exchanger for by-passing the humidifying unit; and a valve in said by-pass duct,
  • a steam radiator comprising a housing having an exhaust port in an upper portion thereof through 1 steam supply duct connected with said inlet to deliver steam to said condensate collecting chamber; and duct means connected between the outlet of said chamber and the radiator for supplying the radiator with steam from the supply line through said chamber, and through which condensate in the chamber is driven therefrom into the radiator by the flow of steam through said chamber.
  • a humidifying device including a housing into which steam is initially admitted into the device and in which condensate forms and-is collected, said housing having a restricted exhaust port in an upper portion thereof, and having an outlet in its bottom portion and a steam inlet in a side thereof spaced a distance above said outlet so that part of the steam admitted into said housing escapes to the atmosphere through said exhaust port While the remainder thereof is constrained to flow downwardly in the housing to discharge therefrom through the outlet in its bottom portion and thereby forcefully expel condensate in the housing out through said outlet; a supply duct for the humidifying device connecting the steam supply line with the inlet of said housing to deliver steam into the interior thereof; duct means connecting the outlet of the housing with said return line for conducting steam, and condensate expelled from the housing thereby, to the return line; and flow control means connected in said duct means for maintainin the steam in said housing at a pressure higher than that obtaining in the return line so as to assure expulsion of condens

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Dispersion Chemistry (AREA)
  • Air Humidification (AREA)

Description

May 8, 1951 G. w. SKILBECK HUMIDIFIER 2 Sheets-Sheet 1 Filed Sept. 25, 1948 4 ww w .Gsrald Ekzlbeck y 1951 G. w. SKILBECK 2,551,708
HUMIDIFIER 7 Filed Sept. 25, 1948 2 Sheets-Sheet 2 Gerald Ekzlbeck Patented May 8, 1951 UNITED STATES PATENT OFFICE HUMIDIFIER Gerald W. Skilbeck, Kenosha, Wis.
Application September 25, 1948, Serial No. 51,287
3 Claims. (01. 237-78) This invention relates to humidifiers and refers more particularly to humidifiers for use with steam heating systems.
A humidifying unit of the type here concerned forms the subject matter of Patent No. 2,395,512 issued to Gerald W. Skilbeck, February 1946 and comprises a humidifying receptacle in the nature of a hollow shell having a side inlet connected with a steam radiator or riser to be plied with steam therefrom and having an exhaust port in its top to enable steam to escape from the receptacle to the atmosphere.
In all humidifiers of this nature the humidify ing receptacle is preferably located close to tlr source of steam so as to be in a zone of relatively high temperature, but condensation of steam entering the humidifying receptacle nevertheless inevitably results. In most cases, the condensate formed in the humidifying receptacle is returned to the system, and the return oi the condensate either to the steam radiator or the riser to which the humidifier is connected has hitherto constituted a difficult problem.
The difliculty of returning the condensate to the steam system arises from the fact that the escape of steam through the exhaust port of the humidifier causes a lower pressure to obtain in the humidifier receptacle than in the steam radiator or riser to which the humidifier is connected, so that the condensate must be delivered from a low pressure zone to a zone of higher pressure.
Previously, it has been proposed to return the condensate to the radiator through the same duct employed to supply the humidifier receptacle 1 with steam. This has invariably proved unsatisfactory and in most instances was inopera tive, for in either event, the operation of the humidifier was attended with loud gurgling noises and condensate being propelled out of the exhaust port into the atmosphere in periodic spurts.
In other instances the condensate was disposed of by being led to an evaporating pad in juxtaposition to the steam radiator, but this expedient of disposing of the condensate is ob- -a viously objectionable because of loss of water from the steam system.
In the aforementioned patent issued to the applicant the problem of returning the condensate to the steam system was overcome by the expedient of providing the humidifier with an elongated discharge tube extending downwardly from the bottom of the humidifier receptacle and bent to form a water seal adjacent to the connection of the discharge tube with 1e steam radiator or riser. Hence, the weight of water in the discharge tube compensated for the loss of pressure in the humidifying receptacle, and controlled return of the condensate to the system was achieved.
The present invention has as its main object the provision of a highly improved manner of effecting return to the steam system of the condensate formed in a. humidifier of the character described.
flore specifically this invention has as its object the provision of an improved manner of installing a humidifying device on a steam radiator or the like, which is characterized by the fact that the humidifier is connected between the source of steam and the radiator so that the pressure in the humidifying receptacle is maintained higher than that obtaining in the radiator, whereby the steam pressure in the humidifying receptacle is employed to return the condensate to the steam system.
Still another object of this invention resides in the provision of air conditioning means for use with steam radiators and the like by which the temperature and humidity of a space being heated may be accurately and automatically controlled.
A further object of this invention resides in the provision of an air conditioning means, for use with steam heating systems, wherein a humidifying unit of the character described is connected between the source of steam and a steam radiator to inject steam into the atmosphere, and wherein an electrically operated valve controlled by a thermostat in the space being heated governs the flow of steam to the humidifying receptacle and consequently to the steam radiator.
With the above and other objects in view, which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention maybe made as come within the scope of the claims.
The accompanying drawings illustrate two complete examples of the physical embodiment of the invention constructed according to the best modes so far devised for the practical application of the principles thereof, and in which:
Figure 2 is an enlarged detail view of the humidifying receptacle and its connection to the steam radiator, portions being broken away and shown in section to illustrate interior details of construction; and
Figure 3 is a slightly modified form of the invention illustrating the manner in which the supply of steam to the humidifier receptacle and the radiator may be automatically controlled by means of an electrically operated valve in the steam supply line-ahead of the humidifier.
Referring now more particularly to the accompanying drawings in which like numerals indicate like parts, the numeral 5 represents a conventional steam heating radiator which, as is customary, comprises a number of spaced: apart vertical radiator sections or flanges communicating at their upper and lower ends. The top of one end section 6 is customarily connected with a source of steam under pressure through a steam supply line I having a valve 8 therein to control the flow of steam into the radiator. The opposite end section 9 has a discharge pipe IO connected to its lower end to return the condensate to the steam system.
If the humidifying device II of this invention is to be applied to an existing radiator installation, the valve 8 in the steam supply line 1 is preferably maintained in closed position, and an inlet duct I2 is connected between the humidifying device and the steam supply line ahead of the valve 8, as shown, so that steam from the supply line flows into the interior of the humidifying device.
As shown best in Figure 2 the humidifying device comprises an outer tubularshell l3 having a bored fitting l4 on its side wall medially of its ends providing a side inlet l5 for the shell through which steam from the supply line enters the same. An exhaust port IS in' the upper end of the shell allows part of the steam admitted into the interior of the shell-to escape into the atmosphere, to thus increase the vapor content thereof.
The humidifying device per se forms no part of the instant invention, and for a more complete disclosure thereof, reference is had to the aforementioned Patent No. 2,395,512. For the purpose of this invention it is sufficient to note, however, that the humidifying device has an inner cup-like receptacle l'i fixed in its upper end and separating the exhaust port Hi from the interior of the shell. The interior of the shell, however, is communicated with the inside of the cup-like inner receptacle by means of a port I 8 in the bottom wall of the inner receptacle which may be adjustably restricted or even closed by means of a ball check I9.
An adjusting screw 20 extends down into the inner receptacle from the top of the shell and has its inner end disposed in the chamber for the ball check to limit the extent to which the ball may be lifted off its seat by steam pressure Within the shell. Consequently, the amount of steam which enters the inner receptacle for discharge through the exhaust port Hi to the atmosphere may be readily controlled by the screw 20'.
A discharge tube 2| connected with the bottom of the shell l3 connects the humidifier with the steam radiator through a metering valve 22. While the metering valve may be directly incorporated in the discharge line 2i in the present case it is shownas a needle valve provided with a side inlet 23 to. which the discharge line is attached, and has its outlet 24 threaded into the end radiator section 6 at the lower portion thereof.
Hence, it will be apparent that in the normal use of the humidifying device, that is, with the valve 3 closed, all of the steam flowing through the supply line I enters the humidifying device, and that part of the steam will escape to the atmosphere through the exhaust port 16 providing the adjusting screw 20 allows limited movement of th ball check [9 off. its seat. The remainder of. the steam and any condensate formed within the humidifier receptacle discharges to the radiator through the discharge line 2! and the metering valve 22.
The metering valve 22 may be employed to regulate the amount of steam admitted into the radiator. Another important function of the metering valve is to assure the maintenance of av higher pressure in the humidifier unit than in the interior of the steam radiator so that the condensate formed within the interior of the humidifier l i may either fiow by gravity through the discharge line 2| into the radiator for return to the system or be forcefully expelled from the bottom of the humidifying device by the pressure of steam therein.
It will be appreciated that the metering valve provides, in effect, an adjustably restricted orifice at the steam inlet of the radiator, and that while sufiicient steam may be caused to flow through the metering valve into the radiator for the proper heating of the space in which the radiator is located durin the coldest weather conditions, the valve also enables the flow of steam into the radiator to be controlled or minimized to the extent avoiding overheating during mild weather conditions. Hence in mild weather the metering valve may be only slightly opened to allow one or two of the first sections or flanges of the radiator to be heated.
It is important to note that by reason of the presence of the metering valve 22, the pressure within the steam radiator may be held to an extremely low value only slightly above atmospheric pressure, eliminating the need for traps or the like in the outlet line H] leading from the radiator.
If a large amount of heatis required at any certain time, it will be readily apparent that the manual control valve 8 may be opened so that the humidifying device I l is bypassed. After all of the sections of the radiator have been supplied with steam in thi manner, however, the valve 8 preferably is again closed and the flow of steam to the radiator controlled by means of the needle valve 22 to avoid overheating of the space in which the radiator is located.
It will be obvious that the installation may operate with the same degree of efiiciency without the by-pass or control valve 8, in which case the steam supply line would connect only with the humidifying receptacle through the inlet duct [2; and all steam admitted into the radiator would first have to pass through the humidifier, assuring positive return of condensate in the humidifier to the system.
If desired, the supply of steam to the humidifying device and consequently to the steam radiator 5 may be automatically controlled by a room thermostat, not shown, in which case a solenoid valve 26 operated by the thermostat is incorporated in the supply line 1 ahead of the humidifying device H. In thi manner the temperature as well as the humidity of the room or other space being heated by the radiator may be accurately controlled.
In the absence of unusual fluctuation in humidity of the outside atmosphere, the humidity of the room or space being heated is accurately maintained at a desirable level after the adjusting screw 2c of the humidifying device ha been properly set. This results from the fact that steam is exhausted into the atmosphere by the humidifier whenever the valve 26 is opened to supply the radiator with steam, t offset the tendency of the air in the space being heated from being dried out.
From the foregoing description taken in connection with the accompanying drawings, it will be readily apparent to those skilled in the art that this invention greatly simplifies and improves the return to the steam system of condensate from humidifiers used with steam radiators and the like, and that the installation is especially well adapted for automatic heating controls to achieve efiicient air conditioning.
What I claim as my invention is:
1. In combination: a heat exchanger; a humidifying unit having an exhaust port through which Water vapor may escape to the atmosphere, and including means defining a chamber into which steam is initially admitted to the unit and in which condensate forms; a steam supplying line connected with said chamber to supply steam to the interior thereof; duct means connecting between the bottom of said chamber and the heat exchanger for conducting steam delivered to said chamber along with condensate formed therein into the heat exchanger, said duct means connecting the heat exchanger with the supply line through said chamber; a duct connected between the steam supply line and the heat exchanger for by-passing the humidifying unit; and a valve in said by-pass duct,
2. In combination: a steam radiator; a humidifying device comprising a housing having an exhaust port in an upper portion thereof through 1 steam supply duct connected with said inlet to deliver steam to said condensate collecting chamber; and duct means connected between the outlet of said chamber and the radiator for supplying the radiator with steam from the supply line through said chamber, and through which condensate in the chamber is driven therefrom into the radiator by the flow of steam through said chamber.
3. In a steam heating system including steam supply and return lines: a humidifying device including a housing into which steam is initially admitted into the device and in which condensate forms and-is collected, said housing having a restricted exhaust port in an upper portion thereof, and having an outlet in its bottom portion and a steam inlet in a side thereof spaced a distance above said outlet so that part of the steam admitted into said housing escapes to the atmosphere through said exhaust port While the remainder thereof is constrained to flow downwardly in the housing to discharge therefrom through the outlet in its bottom portion and thereby forcefully expel condensate in the housing out through said outlet; a supply duct for the humidifying device connecting the steam supply line with the inlet of said housing to deliver steam into the interior thereof; duct means connecting the outlet of the housing with said return line for conducting steam, and condensate expelled from the housing thereby, to the return line; and flow control means connected in said duct means for maintainin the steam in said housing at a pressure higher than that obtaining in the return line so as to assure expulsion of condensate from the housing by the steam discharging into said duct means.
GERALD W. SKILBECK.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,167,815 Gold Jan. 11, 1916 1,896,514 Hoyt Feb. 7, 1933 2,395,512 Skilbeck Feb. 26, 1946
US51287A 1948-09-25 1948-09-25 Humidifier Expired - Lifetime US2551708A (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1167815A (en) * 1913-05-16 1916-01-11 Gold Car Heating & Lighting Co Automatic valve.
US1896514A (en) * 1931-03-06 1933-02-07 Leroy W Hoyt Humidifier
US2395512A (en) * 1942-12-08 1946-02-26 Gerald W Skilbeck Humidifier

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1167815A (en) * 1913-05-16 1916-01-11 Gold Car Heating & Lighting Co Automatic valve.
US1896514A (en) * 1931-03-06 1933-02-07 Leroy W Hoyt Humidifier
US2395512A (en) * 1942-12-08 1946-02-26 Gerald W Skilbeck Humidifier

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