US2205117A

US2205117A - Refrigerating apparatus

Info

Publication number: US2205117A
Application number: US704164A
Authority: US
Inventors: Jewel C Chambers
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1933-12-27
Filing date: 1933-12-27
Publication date: 1940-06-18
Anticipated expiration: 1957-06-18

Description

June 18, 1940. J. c. CHAMBERS REFRIGERATING APPARATUS 5 Sheets-Sheet 1 3 \J. do 1 m B i t j K c w w m 3 -1 v i 11min: ..\H

June 18, 1940. J. c. CHAlMBERS REFRIGERATING APPARATUS Filed Dec. 27, 1933 3 Sheets-Sheet 2 ggfi. 2 K NTOR I ATTORN J. c. CHAMBERS REFRIGERATING APPARATUS:

June 18, 1940.

Filed Dec. 27, 1933 3 Sheets-Sheet 3 a? 2 W ATTORNEEY Patented June 18, 1940 UNITED STATES PATENT OFFICE REFRIGERATING APPARATUS Application December 2'7, 1933, Serial No. 704,164

11 Claims.

This invention relates to the conditioning of air.

It is among the objects of this invention to provide a method and apparatus for conditioning air in which desirable temperature and humidity conditions are maintained notwithstanding variations in the temperature and/or humidity loads placed on the apparatus.

Further objects and advantages of the present invention will be apparent from the following description, reference being hadto the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

Inthe drawings:

Fig. 1 is a horizontal cross-sectional view, somewhat diagrammatic and taken along the line i-l of Fig. 2, of an apparatus embodying features of my invention;

Fig. 2 is a vertical cross-sectional view similar to Fig. 1;

Fig. 3 is an enlarged view showing a detail of one form of damper mounting;

Fig. 4 is an end view of a portion of the apparatus shown in Fig. 3; and

Fig. 5 is a view of a detail of the form of damper mounting for dampers not directly connected to motors.

In practicing my invention, air is supplied to an enclosure it, the air being conditioned to produce the desired temperature and relative humidity conditions in the enclosure II. This is accomplished by causing a stream of air to flow through a plurality of air modifying zones or units Ii and I2 and in varying the character of flow through these zones or units and/or the air modifying intensity of the units so that the desired temperature and humidity conditions are produced in the enclosure l0.

The two or more zones or units II and I! are so arranged with respect to each other that air may flow through these units partly orwhplly in a series relation, partly or wholly in a parallel relation or with a .varying proportion of the stream flowing in series relation and another portion flowing in parallel relation. To this end, the zones or units II and II are preferably arranged in a staggered relationship as shownin Fig. 1, with one of the units, in this case ll, nearer the enclosure it than the other of the units. The means for varying the character of flow of air through the units may take the form of damper means comprising a set of .dampers l3, ll, Ii

and I6 operatively linked together so that they may assume various positions -as indicated in fullanddottedlinesinFlg. 1. Whenthedompers have the position shown in full lines in Fig. 1, the nature of the flow of air is substantially wholly a series flow. When they assume the position indicated by the letter a, the nature of the flow is partly in series and partly in parallel. 5

And when the position of the dampers is that indicated by letters b, the flow of air through the units is substantially a parallel one. That is, one in which the various portions of the air stream flowing through the zones or units do not pass 10 through both zones or units- The means by which the dampers are caused to assume the various positions are hereinafter more fully described.

The zones or units H and I2 may be air modi- 15 parallel relationship, and returning through the 25 evaporated refrigerant line 20 to the compressor 25. The automatic expansion valves l8 and i9 may be controlled by thermostatic bulbs 2i and 22 respectively to maintain the coils in a substantially flooded condition as will readily be under- 30 stood by those skilled in the art.

The nature of the load on the air conditioning apparatus varies from time to time withrespect to the requirements for dehydration and cooling of the air. for these variations. This is accomplished by varying the nature of the flow of air through the air conditioning apparatus in the manner heretofore described and under the automatic .control of the conditions in the enclosure i0 and in varying the air modifying intensity or power, of! the apparatus. To this end, a snap acting wet bulb thermostat (or relative humidity hydrostat) 30 and a snap acting dry bulb thermostat 3|v may be placed in any position to be afiected by 45 the general condition of the air in the enclosure (ll. These controls are connected to the air conditioning mechanism to vary the operation thereof in order to maintain the proper conditions in varies, at times, the air modifying intensity or power of the units I l and H. To accomplish this,

it controls the motor 31 which drives the compressor 25 and causes it to start and stop, which in turn varies the cooling power of the units H Means are provided to compensate and I2 in a manner to tend to maintain the dry bulb in the enclosure IIl within predetermined limits. The wet bulb thermostat 30, which is responsive to humidity conditions in the enclosure, may also vary the air modifying intensity of the units II and I2 and is therefore also connected to the motor 32 to cause the compressor 25 to operate and tend to maintain the relative humidity conditions in the enclosure I0 below a predetermined limit. The compressor 25 is caused to operate whenever the arm 34 contacts at 35a in response to an increase in the wet bulb tem perature in the enclosure III. The controls 30 and Ill are in parallel electrical connection With the motor 32, and either one of the controls can cause the motor to operate, and the motor will continue to operate so long as either control maintains the circuit closed. Thus the compressor 25 operates so long as either the dry bulb or the wet bulb temperature is above its respective predetermined maximum limit, and tends to reduce either temperature below its said maximum limit.

In addition, the wet bulb thermostat 30 controls the nature of the flow of air through or past the units II and I2 to modify the dehydrating capacity of the apparatus. Preferably the flow of the stream of air is such that it has a substantially constant volumetric capacity through the air conditioning apparatus, and the length of contact between portions of said stream and the combined cooling surface or zone of units II and I2 is varied to produce the necessary dehydrating action on the stream. In general, when the nature of the contact is longer, as when the stream flows wholly or largely in series through the units II and I2, the dehydrating action is greater; and, conversely, when the nature of the flow is Wholly or largely in parallel, the dehydrating action is decreased. Thus by varying the nature of the air flow through the units II and I2 in accordance with the humidity conditions in the enclosure I0, the humidity conditions can be controlled or maintained within desired or predetermined limits. To this end, the wet bulb thermostat 30 controls the dampers I3, I4, I5 and I6 and causes them to assume the various positions indicated in full and dotted lines in response to wet bulb temperatures in the enclosure I0. In one embodiment, the dampers are mounted on hinged rods which are placed under the tension of springs M and 42 which exert oppositely directed tortional forces on the rod 40 which are balanced when the dampers assume the position indicated at a in Fig. 1. This may be called the intermediate or normal position of operations. A motor 43 is provided to actuate the dampers I3 and I5 and a-motor 44 is provided to actuate the damp ers I4 and I6 from the normal position. When the wetbulb temperature fallsto, or below, a predetermined limit, the arm 34 contacts at 36 and closes an electrical circuit leading to the

motors

43 and 44 and causes the dampers to assume the position indicated at 11, causing the air to flow in a parallel relationship with respect to the units II and I2. When the air flows in this parallel relationship, the coils produce the minimum or lesser amount of dehydration of the air, since the various portions of the air stream remain the shortest possible length of time in contact with a cooling surface. Thus a relatively large amount of air is cooled, but not to as low a temperature as when a larger series flow is produced. It is to be understood that,

under these conditions. the compressor 25 may or may not be operating depending on the dry bulb conditions. If the dry bulb temperature in enclosure I0 is sufilciently low, the compressor does not operate, and if too high, it does operate. On the other hand, if the wet bulb temperature is at, or above, the upper desired or predetermined limit, the arm 34 contacts at 35a, and the compressor 25 is caused to operate, if it is not already operating under the control of dry bulb thermostat 3|. In addition, the arm 34 contacts at 35 and the dampers assume the position indicated in full lines in Fig. 1 because the motors 43' and 44 are energized to turn in the necessary direction and this causes the maximum amount of series flow in the air stream. Under such conditions, all, or a certain portion, of the air is contacted for the maximum length of time with the cooling surfaces and this dehumidifies the air to the maximum extent and tends to reduce the wet bulb temperature or maintain it below a predetermined maximum limit in the enclosure II).

The

motors

43 and 44 may be of the stall type. When the dampers reach the limit of their movement, the motors stall and maintain the dampers at such limit positions as long as the motors are energized, but when the motors are de-energized, by the breaking of the contact at the wet bulb thermostat 30, then, these springs M and 42 return the dampers to the position indicated at a which is an intermediate position. The drive or gear connection between the

motors

43 and 44 and the rods 40 may be of any type which permits the motors to overcome the springs as long as the motors are energized, but permit the springs to return the dampers to the position a when the motors are de-energized. This can be accomplished either by a proper mutual drive gear relationship between the motor and the rod, causing the motors to stall at the, end of the movement, or it may be accomplished by a slip clutch drive, (magnetic or otherwise) which has a greater power than the springs H and 42 while the motor is operating, (in which case the motors continue to turn until de-energized) and permits the return of the dampers when the motors are not energized.

Any means for causing a flow of air past the air modifying zones II and I2 may be provided. This may take the form of a fan 50, driven by the motor 5| to produce a substantially constant volumetric flow of air through the air conditioning .apparatus. The intake of the fan may be connected to a chamber 52 which in turn is supplied with outside fresh air through the conduit 53 and is supplied with air from the enclosure I0 through the conduit 54. The air thus enters into the chamber 52, enters the fan 50 and is caused to flow through the air conditioning apparatus contained in the casing 55 and is discharged into the enclosure ID.

A permanent airby-pass 60 may be provided around the air modifying units II and I2. This by-pass 60 may be of any desired size, and preferably is of sufllclent size to temper the air conditioned by the units II and I2 to prevent undesirable cold drafts in the enclosure ID. This by-pass is preferably never changed as to size and as to the volume of air flowing therethrough. Thus a stop 6| is provided for damper I4 to prevent it from modifying the size of the by-pass. When the dampers are in position a dampers I6 and I4 are substantially parallel, but when they are inposition b damper I4 is prevented from turning by stop 6|. A lost motion 62 is provided in the linkage 63 between dampers l4 and I6 through which motor 44 drives damper M to permit this converging position between these two dampers. When these dampers are in position b their converging position tends to compensate for the decreased air resistance through the units due to the parallel air flow and thus tends to maintain a fixed ratio of air flow through the units II and I2 and the by-pass 60. The dampers i3 and [5 are provided with a similar linkage 64 and lost motion 65, for turning damper I5 by motor 43, and with a stop 66 which aids in compensating for the varying air resistance at various damper positions and tends to maintain a fixed ratio of volumetric flow between the by-pass 60 and the units II and I2.

While the form of embodiment of the in- Vention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:-

1. An air conditioning apparatus comprising two or more air modifying units, means for causing a stream of air to pass selectively in series or parallel through said units to vary the effect upon the relative humidity of said air.

2. An air conditioning apparatus comprising two or more air modifying units, means for causing a stream of air to pass through said units with a portion of said stream passing in series and another portion passing in parallel, and means for varying the ratio of said portions to vary the effect upon the relative humidity of said air.

3. The method of conditioning air in an enclosure which comprises flowing a stream of air through a plurality of .air modifying zones andinto said enclosure with a portion of said stream flowing through said zones in series and another portion in parallel.

4. The method of conditioning air in an enclosure which comprises flowing a stream of air through a plurality of air modifying zones and into said enclosure with a portion of said stream flowing through said zones in series and another portion in parallel, and varying the ratio of said portions in accordance with conditions in said enclosure.

5. The method of conditioning air which comprises flowing a stream of air through a plurality of air cooling zones with a portion of said stream flowing through said zones in series and another portion in parallel.

6. The method of conditioning air in an enclosure which comprises flowing a stream of air through a plurality of air cooling zones and into said enclosure with a portion of said stream flowing through said zones in series and another portion in parallel, and varying the ratio of said portions in accordance with conditions in said enclosure.

'7. An air conditioning system comprising, in

combination, a heat absorber, the main function of which is to remove principally sensible heat from air flowing thereover, a second heat absorber adapted to cool air flowing thereover to below the dew point'thereof, means responsive to the temperature of the air to be conditioned for controlling the heat exchange between the air and said absorbers, means for controlling the flow of air over the second mentioned heat absorber, and means responsive to the relative humidity of the air to be conditioned for actuating the controlling means.

8. An air'conditioning system comprising, in combination, a heat absorber, the main function of which is to remove principally sensible heat from air flowing thereover, a second heat absorber adapted to cool at least a part of said air to below the dew point thereof, means responsive to the temperature of the air to be conditioned for controlling the heat exchange between the air and said absorbers, means for controlling the flow of air over the second mentioned heat absorber, and means responsive to the relative humidity of the air to be conditioned for actuating the controlling means.

9. An air conditioning system comprising, in combination, refrigerating apparatus including an evaporator, the main munction of which is to remove principally sensible heat from air flowing thereover, a second evaporator adapted to' cool air flowing thereover to below the dew point thereof, means for withdrawing gaseous refrigerant from the evaporators and for condensing the refrigerant and for delivering the same to said evaporators, means responsive to the temperature Of the air to be conditioned for controlling the refrigerating apparatus, means for controlling the flow of air over the second mentioned evaporator, and means responsive to the relative humidity of the air to be conditioned for actuating the second mentioned controlling means.

10. An air conditioning system comprising, in combination, refrigerating apparatus including an evaporator, the main function of which is to remove principally sensible heat from air flowing thereover, a second evaporator adapted to cool at least a part of said air to below the dew point thereof, means for withdrawing gaseous refrigerant from the evaporators and for condensing the refrigerant and for delivering the same to said evaporators, means responsive to the temperature of the air to be conditioned for controlling the refrigerating apparatus, means for controlling the flow of air over the second mentioned evaporator, and means responsive to the relative humidity of the air to be conditioned for actuating the second mentioned controlling means.

11. An air conditioning system comprising, in combination, refrigerating apparatus including an evaporator, the main function of which is to remove principally sensible heat from air flowing thereover, a second evaporator adapted to cool at least a part of said air to below the dew point thereof, means for withdrawing gaseous refrigerant from the evaporators and for condensing the refrigerant and for delivering the same to said evaporators, means for controlling the flow of air over the second mentioned evaporator, and means responsive to the relative humidity of the air to be conditioned for actuating the controlling means.

JEWEL C. CHAMBERS.