US1429973A - Humidity controller - Google Patents

Humidity controller Download PDF

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Publication number
US1429973A
US1429973A US377609A US37760920A US1429973A US 1429973 A US1429973 A US 1429973A US 377609 A US377609 A US 377609A US 37760920 A US37760920 A US 37760920A US 1429973 A US1429973 A US 1429973A
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Prior art keywords
air
valve
humidity
bulb
spring
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US377609A
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Roesch Alfred
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CHARLES J TAGLIABUE MANUFACTURING Co
CHARLES TAGLIABUE Manufacturing CO
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CHARLES TAGLIABUE Manufacturing CO
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F3/00Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems
    • F24F3/12Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling
    • F24F3/14Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling by humidification; by dehumidification
    • 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
    • F24F6/14Air-humidification, e.g. cooling by humidification by forming water dispersions in the air using nozzles
    • F24F2006/146Air-humidification, e.g. cooling by humidification by forming water dispersions in the air using nozzles using pressurised water for spraying
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S261/00Gas and liquid contact apparatus
    • Y10S261/34Automatic humidity regulation
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S261/00Gas and liquid contact apparatus
    • Y10S261/43Air coolers

Definitions

  • - y invention relates to controllers whereby the percentage of humidityin theair of a room or the like is controlled and has for its object to provide an extremely sensitive device of simple construction for automatically controlling the difference between dry and wet bulb temperatures so as to automatically maintain a predetermined percentage of humidity, which may be either approximately constant or of progressive increase or decrease, in the atmosphere of a room or the like, and more particularly where large variations in temperature occur.
  • Figure 1 represents an installation of the invention
  • Fig. 2 is a plan view of the controller
  • Fig, 3 is a side view thereof
  • Fig. 4 is a detail section on the line 4-4 of Fig. 5
  • Fig. 5 is a similar view on theline 5 .5 of Fig. 3.
  • the controller comprises a base 5 of any suitable construction upon which a capsular spring 6. of customary type is mounted and connected by means of a capillary tube 7 with a sensitive member in the form of a bulb 8.
  • 'Amainlever 9 is fulcrumed at 10 upon uprights 11 which project from the base 5 and is provided with an adjustable projection preferably in the form of a screw 12 which is maintained in contact with the capsular spring 6 by means of a spring 13 located between and engaging one end of said lever 9 and the base 5.
  • the main lever 9 carries a capsular spring 14 also of an well known type and connected through t e medium of the capillary tube 15 with a sensitive member which may also be in the form of a bulb 16.
  • a secondary lever17 is pivoted at 18 upon uprights 19 extending from the main lever 9, said lever 17 being provided with an adjusting screw 20 which bears against the capsular spring 14 and is maintained, in contact therewith by a spring 21 located between the two levers 9 and 17.
  • the screw 20 carries a pointer 22 which co-operates with a suitable scale 23' provided upon the lever 17 to visibly indicate the adjusttment to which the screw 20 is set.
  • the base 5 carries a block 24 which is provided with channels 25 and 26 connected by means of pipes27 and 28 with a source of air or other fluid under pressure and with a diaphragm motor valve 29 constructed and arranged to close when pressure is applied to the diaphragm and to open under the action of a spring 29 when the pressure upon said diaphragm is relieved.
  • a valve casing 30 is attached to the block 24 and is provided with an inlet passage 31 communicating with the channel 25 and thus with the supply of fluid under pressure and has an outlet passage 32 communicating with the channel 26 and thus with the diaphragm motor valve 29. Both passages 31 and 32 are also in connection with a chamber 33 in which a valve 34 of the ball type is located, the passage 31 being formed'with a seat for the accommodation of said valve '34.
  • ner end engages the ball valve 34 while its outer end is adapted for engagement by a The diameter of the stem 36.is such that a space exists between itand the passage 35 which space constitutes the actual exhaust passage previously referred to.
  • 38 represents a room in which the temperature throughout a given period may vary, for instance, from 60 to 110 F., especially in the summer time, and in which it is important that the percentage of humidity remain constant regardless of any changes in tilating ducts'40 and 41 in all of which dampers or equivalent devices 42 are located for manually regulating the ventilation.
  • the controller itself preferably enclosed in a casing 5 may be placed in any convenient position preferably outside of the room 38 and is connected by the capillary tubes 7 and 15 respectively with the dry bulb 8 and the wetbulb 16, both of which are located within the room 38 at points where the average temperature prevails.
  • the capsular spring 6, capillary tube 7 and bulb 8 and likewise the capsular spring 14, capillary tube 15 and bulb 16 are partly or wholly filled with a volatile fluid which. will cause the capsular springs 6 and 14 to expand when the bulbs 8 and 16 are subjected to an increase in temperature and to contract when said bulbs are subjected to a decrease in temperature.
  • the wet bulb 16 is provided in the customary manner with a wick 43 depending into a: water tank 44 to which water is supplied through a suitable pipe 45 and in which an overflow 46 is located to conduct any surplus supply of water from said tank.
  • the pipe 27 leads from the controller to a source of air under pressure while the pipe 28 leads to the diaphragm motor valve 29, which in the illustrated example controls a water supply pipe 47 which terminates, within the room 38, in a spray nozzle 48 preferably located within an open ended tube 49 as shown.
  • the spray issuing, from the nozzle 48 humidifies the air surrounding it and causes a downward movement of said air whereby a circulation is created in the room 38, by way of the air inlet duct 39 and the ventilating ducts 40 and 41 which may be manually regulated by means of the dampers 42.
  • the dry bulb temperature may vary from 60 to 110 F. during a given period of time and that 48% of humidity is desired to be maintained in the room 38 throughout said period.
  • a dry bulb or air temperature of 60 F. and a ten degrees depression of the wet bulb equals 48% of humidity
  • a dry bulb or air temperature of 110 F. a nineteen degrees depression of the wet bulb equals 48% of humidity.
  • the humidity will reach at a dry bulb temperature of 110 F. according to said psychrometrictables.
  • The'controller is adjusted for a dry bulbtemperature of 60 and a wet bulb temperature of 50 by properly setting the screw 20 and its ointer 22 with respect to the scale 23. Wi this adjustment and assuming that the dry bulb temperature is at 60 F. and the wet bulb temperature is at 50 F. to maintain the 48% of humidity, the lug 37 of the secondary lever 17 is in contact with but exerts practically no pressure on the valve stem 36. Atthis stage the ball valve 34 is maintained in a position by the air pressure to close the exhaust passage 35 and thus permit the air pressure to reach the diaphragm valve 29, which is thus in its closed position.
  • the device may readily be modified to also automatically control any gradual increase or decrease of the percentage of humidity desired in a given period of time and in'relation to any increase or decrease in the dry bulb temperature. This may be done by changing the relative location of the fulcrums of the operating levers so that the difference in the temperatures of the dry and wet bulbs will be increased or decreased as the room temperature rises or falls. 4 The same results may be accomplished by using a fluid in' one of the bulbs which has a greater expansibility or creates a greater pressure for each, degree increase in the dry bulb temperature, than the fluid in the other bulb.
  • My invention is simple in construction and in operation and once it is set requires no attention as its operation is entirely automatic and in accordance with predetermined desires.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Cultivation Of Plants (AREA)

Description

A. ROESCH.
HUMIDITY CONTROLLER.
APPLICATION FILED APR. 29,1920. v lg4293973 26, 19220 2 SHEETSSHEET I.
ATTORNEYS A. ROESCH.
HUMIDITY CONTROLLER.
APPLICATION FILED APR. 29, 1920 ,4 7 Patented Sept. 26, 192 2 v I E 2 SHEETSSAHE ET 2.
W R V WITNESSES A TTOHIVEVS Patented Set. 26, 1922.
ALFRED ROESCH, 01E BROOKLYN,
Amm- OFFICE.
NEW YORK, ASSIGNOR TO CHARLES J. TAGLIABUE MANUFACTURING 00., OI BROOKLYN, NEW YORK, A
CORPORATION NEW YORK.
HUMIDITY CONTROLLER. I
Application filed. April 29, 1920. Serial No. 377,609.
I To all whom it may concern Be it known that I, ALFRED Ronsori, a citizen of the United States, and resident of the boron h of Brooklyn, county of Kings,
city and tate of New York, have invented certain new and useful Improvements in Humidity Controllers, of which the followin is a specification;
- y invention relates to controllers whereby the percentage of humidityin theair of a room or the like is controlled and has for its object to provide an extremely sensitive device of simple construction for automatically controlling the difference between dry and wet bulb temperatures so as to automatically maintain a predetermined percentage of humidity, which may be either approximately constant or of progressive increase or decrease, in the atmosphere of a room or the like, and more particularly where large variations in temperature occur.
My invention will be fully described hereina-fter and the features of novelty will be pointed out in the appended claims.
In the accompanying drawings which, for illustrative and descriptive purposes and without intent to define the limits of the invention, show an example thereof and of its application, Figure 1 represents an installation of the invention; Fig. 2 is a plan view of the controller; Fig, 3 is a side view thereof; Fig. 4 is a detail section on the line 4-4 of Fig. 5, and Fig. 5 is a similar view on theline 5 .5 of Fig. 3.
As shown more particularly in Figs-2, 3 and 4, the controller comprises a base 5 of any suitable construction upon which a capsular spring 6. of customary type is mounted and connected by means of a capillary tube 7 with a sensitive member in the form of a bulb 8. 'Amainlever 9 is fulcrumed at 10 upon uprights 11 which project from the base 5 and is provided with an adjustable projection preferably in the form of a screw 12 which is maintained in contact with the capsular spring 6 by means of a spring 13 located between and engaging one end of said lever 9 and the base 5. The main lever 9 carries a capsular spring 14 also of an well known type and connected through t e medium of the capillary tube 15 with a sensitive member which may also be in the form of a bulb 16. A secondary lever17 is pivoted at 18 upon uprights 19 extending from the main lever 9, said lever 17 being provided with an adjusting screw 20 which bears against the capsular spring 14 and is maintained, in contact therewith by a spring 21 located between the two levers 9 and 17. In the preferred arrangement the screw 20 carries a pointer 22 which co-operates with a suitable scale 23' provided upon the lever 17 to visibly indicate the adustment to which the screw 20 is set.
The base 5 carries a block 24 which is provided with channels 25 and 26 connected by means of pipes27 and 28 with a source of air or other fluid under pressure and with a diaphragm motor valve 29 constructed and arranged to close when pressure is applied to the diaphragm and to open under the action of a spring 29 when the pressure upon said diaphragm is relieved. A valve casing 30 is attached to the block 24 and is provided with an inlet passage 31 communicating with the channel 25 and thus with the supply of fluid under pressure and has an outlet passage 32 communicating with the channel 26 and thus with the diaphragm motor valve 29. Both passages 31 and 32 are also in connection with a chamber 33 in which a valve 34 of the ball type is located, the passage 31 being formed'with a seat for the accommodation of said valve '34. The
ner end engages the ball valve 34 while its outer end is adapted for engagement by a The diameter of the stem 36.is such that a space exists between itand the passage 35 which space constitutes the actual exhaust passage previously referred to.
lug 37 located on the secondary lever 17.
In the example of installation chosen for A illustrative purposes and shown in. Fig. 1, 38 represents a room in which the temperature throughout a given period may vary, for instance, from 60 to 110 F., especially in the summer time, and in which it is important that the percentage of humidity remain constant regardless of any changes in tilating ducts'40 and 41 in all of which dampers or equivalent devices 42 are located for manually regulating the ventilation.
The controller itself, preferably enclosed in a casing 5 may be placed in any convenient position preferably outside of the room 38 and is connected by the capillary tubes 7 and 15 respectively with the dry bulb 8 and the wetbulb 16, both of which are located within the room 38 at points where the average temperature prevails. It will be understood that the capsular spring 6, capillary tube 7 and bulb 8 and likewise the capsular spring 14, capillary tube 15 and bulb 16 are partly or wholly filled with a volatile fluid which. will cause the capsular springs 6 and 14 to expand when the bulbs 8 and 16 are subjected to an increase in temperature and to contract when said bulbs are subjected to a decrease in temperature. The wet bulb 16 is provided in the customary manner with a wick 43 depending into a: water tank 44 to which water is supplied through a suitable pipe 45 and in which an overflow 46 is located to conduct any surplus supply of water from said tank.
The pipe 27 leads from the controller to a source of air under pressure while the pipe 28 leads to the diaphragm motor valve 29, which in the illustrated example controls a water supply pipe 47 which terminates, within the room 38, in a spray nozzle 48 preferably located within an open ended tube 49 as shown. The spray issuing, from the nozzle 48 humidifies the air surrounding it and causes a downward movement of said air whereby a circulation is created in the room 38, by way of the air inlet duct 39 and the ventilating ducts 40 and 41 which may be manually regulated by means of the dampers 42.
By way of example let it be assumed that, as before stated, the dry bulb temperature may vary from 60 to 110 F. during a given period of time and that 48% of humidity is desired to be maintained in the room 38 throughout said period. According to the psyehrometric tables issued by the Bureau of Standards, a dry bulb or air temperature of 60 F. and a ten degrees depression of the wet bulb equals 48% of humidity, while with a dry bulb or air temperature of 110 F. a nineteen degrees depression of the wet bulb equals 48% of humidity. In order to maintain approximately a 48% of humidity at all stages during the change in the dry bulb temperature from 60 to 110 F., it is therefore necessary to provide for a gradual increase in the difference between the dry and wet bulb temperatures. If this is not done and the difference between said dry and wet bulb temperatures is permitted to remain substantially constant at ten degrees,
the humidity will reach at a dry bulb temperature of 110 F. according to said psychrometrictables.
In theillustrated example the desired result, that is, the maintenance of the humidity at approximately 48%, is secured as follows:
The'controller is adjusted for a dry bulbtemperature of 60 and a wet bulb temperature of 50 by properly setting the screw 20 and its ointer 22 with respect to the scale 23. Wi this adjustment and assuming that the dry bulb temperature is at 60 F. and the wet bulb temperature is at 50 F. to maintain the 48% of humidity, the lug 37 of the secondary lever 17 is in contact with but exerts practically no pressure on the valve stem 36. Atthis stage the ball valve 34 is maintained in a position by the air pressure to close the exhaust passage 35 and thus permit the air pressure to reach the diaphragm valve 29, which is thus in its closed position.
If new the dry bulb temperature rises the corresponding expansion of the fluid in said dry bulb 8 will create a higher pressure in the capsular spring 6 thereby expanding the same and pivotally raising the main lever 9 and compressing the spring 13. This pivotal movement of the main lever 9 is partaken of by the secondary lever 17 with the result that the lug 37 exerts a push upon the stem .36 whereby the latter is moved inward and the ball valve 34 is forced away from the inner end of the exhaust passage 35 and toward the inner end of the air passage 31. The supply of air under pressure is thus wholly or partly cut off from the valve 29 which as a result is opened by the action of its spring 29 and thus causes a spray to issue from the nozzle 48. This brings about an increase of humidity in the air of the room 38 and raises the wet bulb temperature which creates a higher pressure in the capsular spring 14 and thereby expands the same. This expansion is communicated to the screw 20 and pivotally moves the secondary lever 17 to compress the spring 21 and tolift the lug 37 away from the end of the stem 36; it will be understood that the action of the capsular spring 14 and the movement of the secondary lever 17 are relative to the main lever 9. As the lug 37 is raised and thus relieves the stem 36 from restraint, the air pressure will cause the ball valve 34 to close the exhaust passage 35 and to establish communication between the channels 31 and 32 by way of the chamber 33. The pressure will thus act upon the diaphragm of the valve 29 and cause the same to close thereby shutting off the supply of water to the nozzle 48. A reduction of the dry or wet bulb temperature will have an opposite effect upon the humidity valve 29.
This alternate operation of the main and secondary levers through the expansion or till described may be made within the scope of.
rename 3r contraction ofthe capsular springs 6 and 14: is repeated throughout the given period of time during which the percentage of humidity in the air is to be maintained.
In the illustrated example the multiplication of the movement of the secondary lever 17, with relation to the movement of the main lever 9, is somewhat less and as the temperature increases and the capsular springs 6 and 14 expand at the same ratio, following each other, the differences between the dry and wet bulb temperatures will therefore be gradually increased, until it is 19 F. at a dry bulb temperature of 110 F. The humidity of 48 per cent is thus maintained, within a very slight variation,-
throughout the rise from; to 110 F. It will be understood that the apparatus may be set for other combinations with equal facilityand that the same eflioient results will in each case be automatically obtained.
The device may readily be modified to also automatically control any gradual increase or decrease of the percentage of humidity desired in a given period of time and in'relation to any increase or decrease in the dry bulb temperature. This may be done by changing the relative location of the fulcrums of the operating levers so that the difference in the temperatures of the dry and wet bulbs will be increased or decreased as the room temperature rises or falls. 4 The same results may be accomplished by using a fluid in' one of the bulbs which has a greater expansibility or creates a greater pressure for each, degree increase in the dry bulb temperature, than the fluid in the other bulb.
My invention. is simple in construction and eficient in operation and once it is set requires no attention as its operation is entirely automatic and in accordance with predetermined desires.
Various-changes in the form shown and the claims without departing from the spirit of my invention.
I claim: LThe combination of air-humidifying means, a dry bulb, a wet bulb, expansible and contractible devices connected respectively withsaid bulbs and capable of independent operative expansive and contractive movements in the same directions, and means operated alternately by said devices to automatically control the humidifying means in accordance with the differences between the dr bulb and wet bulb temperatures to provi e predetermined percentages of humidity in said air.
2. The combination of air-humidifying means, a diaphragm motor valve controlling the same, an air controlling valve whereby air under pressure is admitted to and'cut ofi from said diaphragm valve, a pivoted main lever, a secondary lever pivotally mounted on said main lover, a capsular spring, a, dry bulb connected therewith whereby said capsular spring is caused to operate both levers and thereb actuate said air controlling valve to out o the air pressure from said diaphragm motor valve to permit same to open, a second capsular spring carried by said main lever and having operative movements in the same direction as said first capsular spring, a wet bulb connected with said second capsular spring and whereby the latter is caused to actuate said secondary lever relatively to the main lever and thereby actuate said air controlling valve to admit air pressure to said diaphragm motor valve to close the same.
3. The combination of air-humidifying means, a diaphragm valve controlling the same, an air controlling valve whereby air under pressure is admitted to and cut ofi from said diaphragm valve, a pivoted main lever, a secondary lever pivotally mounted on said main lever, a dr bulb, a wet bulb, and means connected with said bulbs and having operative movements whereb said levers are coincidentally operate and whereby said secondary lever is independently operated to actuate said air controlling valve to alternately cut ofi and admit air pressure to said diaphragm motor valve and thereby alternately open and close the latter. I
In testimony whereof I have hereunto set In hand; y ALFRED ROESCH.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2528368A (en) * 1946-03-01 1950-10-31 Bristol Company Humidity control
US3078780A (en) * 1958-11-24 1963-02-26 Bottlander Wilfried Ventilating arrangement for buildings, more especially greenhouses
US3282514A (en) * 1963-03-12 1966-11-01 Metallgesellschaft Ag Method for controlling the amount of liquid added to heat absorbing gases

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2528368A (en) * 1946-03-01 1950-10-31 Bristol Company Humidity control
US3078780A (en) * 1958-11-24 1963-02-26 Bottlander Wilfried Ventilating arrangement for buildings, more especially greenhouses
US3282514A (en) * 1963-03-12 1966-11-01 Metallgesellschaft Ag Method for controlling the amount of liquid added to heat absorbing gases

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