US2400214A

US2400214A - Refrigeration

Info

Publication number: US2400214A
Application number: US447784A
Authority: US
Inventors: Arnold D Siedle
Original assignee: Hoover Co
Current assignee: Hoover Co
Priority date: 1942-06-20
Filing date: 1942-06-20
Publication date: 1946-05-14
Anticipated expiration: 1963-05-14

Description

I y 1946- 1 .A.. D. SIEDLE I I 2,400,214

REFRIGERATION Filed June 20, 1942 3 Sheets-Sheet -1 l as:

INVENTOR Arnold .19. Siedle ATTORNEY May 14, 1946. AID. SIEDLE REFRIGERATION Filed June 20, 1942 a Sheets-Sheet 2 INVEVNTOR- Arnoldfliedle I ATTORNEY May14 1'946. A. D. SIEDLE 2,400,214

R REFRIGERATION I Filed June 20, 1942 s shet -sheet 3 mvsmmm Alwaldflmac-Ram R m'r'mwmw Patented May 14, 1946 UNITED STATES PATENT OFFICE a corporation of Ohio Application June 20,

17 Claims.

This invention relates to refrigeration and more particularly to a three-fluid absorption refrigerating apparatus utilizing a motor-driven fan for circulating the inert gas in a closed circuit between the evaporator andabsorber and utilizing a portion ofthe gas at its raised pressure for cirrulating the solution between the generator and the absorber in which the motor fan unit is sealed within the walls of the apparatus and so placed relative to the other parts oi the apparatus that the motor fan unit is located in the volumetric center of the apparatus taken as a whole. The motor fan unit is preferably of a type which is so constructed that lubricant therein will not be spilled therefrom regardless of the position in which the unit is placed.

In absorption refrigerating machines using a hermetically sealed motor driven fan for circulating the fluids in the apparatus, the problem of lubricating moving parts of the motor is not sim- Die. The motor fan unit must be so constructed that the lubricant will always remain in position to lubricate the unit during operation and so that it willnot be spilled from the unit casing into other parts of the apparatus when the apparatus is tipped or upended from its normal upright position such as during shipment and other handling operation. One manner of constructing such a motor is disclosed in the patent to Coons et al. 2,271,514, granted February 3, 1942.

Another problem peculiar to such systems is the prevention of the liquid normally contained in the apparatus from entering the casing 01' the motor fan unit when the apparatus is tipped or upended from its normal upright position. It is with the latter problem that this invention is particularly concerned.

According to this invention a motor fan unit for circulating the mediums in a three fluid absorption refrigerating apparatus of the type disclosed in the Coons et a1. Patent 2,271,544, above referred to, is so related -to the other parts of the apparatus that when the volumes of the various vessels are taken into consideration the motor fan unit will be at the volumetric center of the apparatus, In addition the conduits connecting the various parts of the apparatus are so related to those parts that liquid can drain from those parts to other arts and vice versa without passing through the casing of the motor ian unit. Another feature of the invention is that the vari-' ous parts of the apparatus are so positioned rela-' tive to eachother that when the quantity or liquid in the apparatus and thevolume of the various parts is taken into consideration, the vol- 1942, Serial No. 447,784 (cl. 62-1195) ume of the apparatus in any radial direction from its volumetric center is sufllcient to hold the entire amount of liquid contained in the apparatus without flooding the casing of the motor fan unit. Thus if the machine is tipped, upended or laid on its side or back during shipment or other handling operation the liquid can flow to the side which happens to be lowest and return again when the machine is replaced in its upright position without passing through the casing of the motor fan unit, and the parts of the apparatus below the casing of the motor fan unit when the machine is in a tipped position will be sufficient to hold the entire liquid charge in the apparatus without flooding the casing of the motor fan unit regardless of the position in which the apparatus may he placed.

According to a modified form of the invention, an auxiliary reservoir is provided in a vent con- 20 duit to increase the volume of the parts of the apparatus on one side of the motor fan casing. This will insure that the volume of the apparatus on that side is sufficient to hold the entire liquidcharge so that the casing of the motor Ian unit will not be flooded when the machine is tipped from its normal upright position. Under ordinary conditions the auxiliary reservoir has no useful function and functions only as a liquid receiver when the apparatus is displaced from a its normal upright position.

The refrigerating system to which this invention is applied is well .known in the art and is disclosed and claimed more fully in a co-pending appiication by Curtis C. Cons and William H. Kitto, Serial No. 386,395, filed April 2, 1941., now Patent No. 2,328,196 dated August 31, 1943, as a continuation-in-part of an application Serial No. 220,189, flied July 20, 1938. v

Other objects and advantages of this inven- 0 tion will become apparent when taken in connection with the accompanying drawings, in which Figure 1 is a perspective view of a refrigerating apparatus according to this invention depicting the parts in their proper relationship for assembly with a domestic refrigerator cabinet;

Fi ure 2 is a perspective view of a modified form of the invention; and

Figures 3, 4, 5 and 6 show schematically how the liquid in the system flnd their-levels as the system is placed in various positions.

Referring to Figure 1 the various parts of the refrigerating apparatus are mounted on a frame generally indicated at il in which the parts are so related to each otherthat they can be assembled and disassembled from a domestic refrigerator cabinet generally indicated at l2.

The system is suitably charged with ammonia as the refrigerant, water as the absorbent and with an inert gas such as hydrogen. A fan 2 driven by an electric motor 4 circulates the inert gas between the evaporator and the absorber in a circuit which will be described more in detail hereinafter. The fan 2 and motor 4 are preferably constructed as shown and described in the patent to Coons et al. 2,271,544.

The apparatus includes the generator I4, having an analyzing dome l8 extending upwardly therefrom. A conduit l8 extends from the top of the analyzer l upwardly to a condenser 20 and includes a rectifier 22 having a plate-like fin 24 bonded thereto. The condenser 20 comprises a serpentine coil having air cooling fins thereon and its lower end is connected to the bottom of the evaporator in the manner described in the aforementioned patent to Coons et a1. 2,271,544.

The generator I 4 is connected by the inner passageof liquid heat exchanger 25 and conduit 26 to a liquid reservoir 28. The conduit 26 extends into the reservoir 28 along the bottom thereof as shown. The conduit 28 may have cooling fins thereon to act as a pre-coolerfor the absorption solution flowing to the reservoir 28. A conduit 38 leads from the reservoir 28 to the junction of a pair of

conduits

32 and 54 which extend vertic lly and enter aconduit 26 forming a portion of the inert gas circuit and leading to the top of the absorber as. A bleed conduit 40 branches off from the fan discharge conduit 42 and is connected to the bight of an inverted U- shaped conduit 44, the legs of which enter the

conduits

32 and 84 at a point below the liquid level normally maintained in the generatoranalyzer-reservoir system. A vent conduit 48 connects the top of the reservoir 28 to the conduit 86.

The absorber 38 consists of a coil of tubing arranged in a serpentinefashion in substantially a singl inclined plan'e sloping downwardly toward the rear of the unit as shown. Each leg of each coil is higher than the next succeeding leg toward the rear of the machine and one end of each leg is higher than the other so that the absorber 38 has a continuous downward slope throughout from one end to the other.

From the lowest end of the lowest coil of the absorber 38 a conduit 46 leads to the outer pass of liquid heat exchanger 2a. The conduit 40 connects the'outer pass of liquid heat exchanger 25 to the upper end Of the analyzer I 8.

The discharge conduit 42 of the fan 2 is connected to the outer pass of a gas heat exchanger 58 of any suitable construction known to the art preferably of the concentric tube type. The gas heat exchanger 58 is preferably covered with insulation 52. The innerand outer passages of the gas heat exchanger 58 are connected to the evaporator 54 in the manner shown and described in the aforementioned application of Curtis C.

. Coons and William H. Kitto, Serial No. 386,395,

7 housing for the condenser 25 and the rectifier 22.

The apparatus constructed as described is adapted to be assembled with cabinet l2, with the generator l4, absorber 38, reservoir 28, fan 2 and motor 4 together with the necessary connecting conduits positioned in the apparatus compartment of the cabinet l2 and with the evaporator extending-through an opening '62 in the back of the cabinet l2.

Briefly the machine operates in the following manner: Heat is applied to the generator i4 in any suitable'manner as by a gas burner. The vapor thus generated flows upwardly through the analyzer IS in counterflow to strong solution. The vapor then flows by conduit l8 and rectifier 22 to the condenser 28. The vapor will contain some water vapor which will condense in the rectifier 22 by the transfer of its heat of condensation to cooling air and flow back to the analyzer l6. In the condenser the refrigerant vapor is condensed by the transfer of its heat of condensation to the cooling air flowing upwardly through the flue at the back of the cabinet and the condensed refrigerant flows to the evaporator 54.

The weakened solution formed in the generator l4 flows through the inner pass of the liquid heat exchanger 25 and pre-cooler 28 to the reservoir 28. A portion of the inert gas placed under pressure by the fan 2 flows by conduits 42, 40 and 44 to the

conduits

32 and 84. The point of connection of the inverted U-shaped conduit 44 with the conduits 22 and 34 is below the liquid level normally maintained in the generator-analyzerreservoir system. The inert gas entering the conduits 32 and 34 from the inverted U-shaped conduit 44 forms slugs of liquid refrigerant in the

conduits

32 and 54 separated by gas pockets whereby the weak liquid is raised upwardly to the conduit 88 by gas lift action from where it flows downwardly by gravity through the tubes of the absorber 88 in counterflow to the inert gas refrigerant vapor mixture flowing upwardly therethrough whereby the absorption liquid absorbs the refrigerant vapor from the mixture and becomes enriched in ammonia.

From the bottom of the absorber 38 the strong solution return to the top of the analyzer l8 by tis c. Coons and William H. Kitto, Serial No. 386,-

395, filed April 6, 1941.

As previously stated, the fan 2 and motor 4 are preferably constructed in a manner shown and described in the patent to Coons 2,271,544 but since its use with the refrigerating apparatus constructed according to this invention forms a new combination, it will be described in detail herein insofar as pertinent to an understanding of the invention.

Referring to Figure- 3, the motor fan unit I comprises a fan casing 54 undo. cylindrical shell 58 forming a housing for the fan 2 and the motor rotor 88. The motor rotor 88 is connected to the fan 2 by a shaft which is suitably supported for rotation on bearing assemblies 18 and 12. On the exterior or the shell 55 opposite the rotor 88 is a field stack 14 having windings 15. The rotor aeoaeri is preferably of the squirrelcage type having cast aluminum conductor bars and end rings and is submerged in a lubricant in the interior of the shell 88 to the level shown in Figure 3.

In order to hold the lubricant in the interior of the shell 86 when the apparatus is being shipped or during other handling operations a partition member I8 having an opening for the motor shaft is secured to the interior of the casing 64 in any suitable manner. The partition 18 has a downwardly extending portion 88 for a purpose to be described later. The partition 18 forms with the bottom of the casing 84 and the shell 88 a reservoir for holding the oil in the shell 88, regardless of the position in which the apparatus is placed. A disc 82 is preferably secured to the motor shaft intermediate the rotor 68 and sleeve 80 on the partition 18. The principal function of the disc or throw-off ring 82 is to prevent oil from creeping up the shaft and Any oil which does escaping from the reservoir. reach the disc is thrown off by centrifugal action and returned to the main body through openings 84. The disc 82 also serves'as a seal closing the vent existing between the motor shaft and the tube 88 under certain circumstances. Thus if the apparatus is upended for any reason the weight of the rotor 88 will bring the-disc 82 into sealing engagement withthe lower ends of the sleeve 80- and tube 88, thereby preventing lubricant from escaping or liquids within the apparatus from entering. As soon as the apparatus is returned to normal operating position, the rotor will fall backinto the position shown in Figure 3 and the vent will againbe opened. In order to assure a positive seal between the disc 82 and the sleeve 88, the cooperating faces of these elements may be suitably shaped and, if desired, one or both may be surfaced with a which will have long life and will not be affected by the mediums within the system. 1

Thus it can be seen that the amount of oil in the shell 66 necessary to cover the rotor is very small and that, therefore, the size of the reservoir formed by the partition 18 and shell 88 need not be large in order to hold all the oil in any position that the apparatus may be placed.

The motor fan unit, the generator-analyzerliquid heat exchanger assembly, the reservoir 28, the absorber 38, the evaporator 58, the condenser 20' and the gas heat exchanger are so placed soft sealing material,

will drain to the solution circuit through the conduits l8 and M.

The way in which the liquid in the apparatus finds its level below the casing of the motor fan unit is schematically illustrated inFigures 3, 4, 5 and 6. In Figure 3, the unit is positioned in the normal upright position. The liquid level is below the entrance of any conduit into the easing of the motor fan unit and the oil level in the casing or shell 88 is below the vent through the partition 18.

From the position shown in Figure 3 the ma- I chine may be moved to the position shown in Figure 6 where the unit is schematically illustrated a being'on its'side, back or front. The liquid will flow through "the various conduits similar to following the inner spherical surface of the sphere and find its level below the point of entrance into the casing of the motor fan unit.

At no point during the movement of the machine from its vertical to a horizontal position will the liquid level in the machine rise to a point where it can enter the casing of the motor fan unit. At

relative to each-other and, their capacity so chosen that the motor fan unit will be positioned in the volumetric center of the apparatus and yet have the vertical spacing of the various-vessels arranged for proper operation of the system.

The capacity of the vessels and their relative positions are also sochosen relative to the total quantity of liquid in the system that regardless of I the position in which the machine may be placed,

the liquid level will never reach the housing 84' and shell 88 of the motor fan unit.

The conduits connecting the variousvessels are so related to the vessels that liquid in any particular' vessel may flow from and return to that vessel as the machine is moved from its normal vertical position to any other position and back to tering the shell 88 of the motor fan unit.

when the machine is not in operation all of the liquid drains to the generator-analyzer-reservoir sytem. Any liquid which may find its way into the ou Pass of the gas'heat exchanger 50 when the machine is in operation or otherwise,

.. a normal vertical positionwithout the liquid en the same time the lubricant in the motor shell 88 will'never reach a level where it can flow through the vent in the partition 18. The same is true of the positions illustrated in Figures 4, and 5.

Figure 2 shows a slightly modified form of the invention and the correspondingparts will be given the same reference numerals 'as in Figure 1. In this modification a reservoir 98 is positioned in the vent line 48 and is located at the side of the apparatus opposite the reservoir 28. The purpose of the reservoir is to.change the volumetric capacity of one portionofthe apparatus relative to anothe portion so that. the relative position of the other parts of the apparatus need not belo'catedwith such exactitude nor their capacity changed materially. from the normal capacity.

In Figure 2 the generator-analyzer-heat exchanger assembly is shown as being, embedded in insulation 92 and the conduit l8 Joining. the top of the analyzer to the rectifier 22 is shown as being covered with insulation 84. It is to be'understood'that a similar procedure is to be followed with regard to Figure ,1 but in Figure 1 this insulation was omitted so as to better depict the formation of those parts.

From the foregoing it can be seen that this invention provides a three-fluid absorption refrigerating apparatus having a motor driven fan for circulating the mediums within the apparatus, hermetically sealed within the walls of the apparatus so that the liquid mediums normally contained in the apparatus can. never enter the casing of the motor fan unit and the lubricant in the motor casing can never flow therefrom regardless of the may be placed during shipment or other handling operations. 7

.While I have shown but a number of modifications of my invention, it is to be understood that these modifications are to be taken as illustrative only and not in a limiting sense. I do not wish tobe limited to the specific structure shown and describednbut to'include-all equivalent variations thereof except as limited by the scope of the claims.

I claim:

1. An absorption refrigerating apparatus ineluding a motor fan unit for circulating the me:

diums in said apparatus, said motor fan unit being so positioned that the center of said unit position in which the apparatus coincides with the volumetric center of said apparatus.

2. An absorption refrigerating apparatus including a motor fan unit of the hermetically sealed type for circulating the mediums in said apparatus, said motor fan unit being so positioned that the center of said unit coincides with the volumetric center of said apparatus.

3. An absorption refrigerating apparatus comprising, a plurality of vessels including a generatOr assembly, a condenser, an evaporator, an absorber, a solution reservoir, a closed solution circuit including said generator assembly, reservoir and absorber, a closed inert gas circuit including said absorber and evaporator and a motor fan unit for circulating the mediums in the apparatus, said motor fan unit being so positioned that its center coincides with the volumetric center of said apparatus.

4. An absorption refrigerating apparatus comprising, a plurality of vessels including, a generator assembly, a condenser, an evaporator, an absorber, a solution reservoir, a closed solution circuit including said generator assembly, reservoir and absorber, a closed inert gas circuit including said absorber and evaporator and a motor fan unit of the hermetically sealed type for circulating the mediums in the apparatus, said motor fan unit being so positioned that its center substantially coincides with the volumetric center of said apparatus.

5. An absorption refrigerating apparatus comprising, a plurality of vessels including, a generator-assembly, a condenser, an evaporator, an absorber, a solution reservoir, 9. closed solution circuit including said generator-assembly, reservoir and absorber, a closed inert gas circuit ineluding said absorber and evaporator and a motor fan unit of the hermetically sealed type for circulating the mediums in the apparatus, said motor fan unit being so positioned that its center substantially coincides with the volumetric center of said apparatus.

6. An absorption refrigerating apparatus comprising, a plurality of vessels including, a generator assembly, a condenser, an evaporator, an absorber, a solution reservoir, a closed solution circuit including said generator assembly, reservoir and absorber, a closed inert gas circuit including said absorber and evaporator and a motor fan unit for circulating the mediums in said apparatus, said motor fan unit including a hermetically sealed casing forming part of said inert gas circuit and the arrangement of said vessels relative to said center of said casing being such that the casing substantiall coincides with the volumetric center of said apparatus and the volumetric capacity of the apparatus on either side.

of any plane cutting said casing being greater than the total volume of liquid medium normally contained in the apparatus. v 7. An absorption refrigerating apparatus comprising, a plurality of vessels including a generator rssembly, a condenser, an ev porator, an absorber, a solution reservoir, a cl solution circuit including said generator assembly, reservoir and absorber, a closed inert gas circuit including said absorber and evaporator and a motor fan unit for circulating the mediums in said apparatus, said motor fan unit including a hermetically sealed casing forming part of the inert gas circuit and containing a lubricant for lubricating the moving parts thereof, the construction and arrangement being such that the lubricant in 5 volumetric capacity of the apparatus on either side of any plane cutting said casing being in excess of the total volume'of liquid mediums normally contained in said apparatus.

8. An absorption refrigeratin apparatu comlO prising, a plurality of vessels including, a generator assembly, a condenser, an evaporator, an absorber, a solution reservoir, 9. closed solution circuit including said generator assembly, reservoir and absorber, a closed inert gas circuit ineluding said absorber and evaporator and a motor fan unit for circulating the mediums in the apparatus, said motor fan unit being so positioned that its center substantially coincides with the volumetric center of said apparatus and the connections to the various vessels being such that liquid contained in any vessel may flow to another vessel by-passing the motor fan unit.

9. An absorption refrigerating apparatus comprising, a plurality of vessels including a generator assembly, a condenser, an evaporator, an

absorber, a solution reservoir, a closed solution circuit including said generator assembly, reservoir and absorber, a closed inert gas circuit including said absorber and evaporator and a motor fan unit for circulating the mediums in said apparatus, said motor fan unit including a hermetically sealed casing forming a part of said inert gas circuit and containing a lubricant, said casing being so constructed and arranged that the lubricant cannot flow therefrom regardless of the position in which the casing is placed and being so related to said vessels of the apparatus that the liquid medium contained in the apparatus cannot enter said casing regardless of the position in which said apparatus is placed.

10. An absorption refrigerating apparatus comprising, a plurality of vessels including. a generator assembly, a condenser, an evaporator, an absorber, a solution reservoir, a closed solution circuit including said generator assembly, reservoir and absorber, a closed inert gas circuit including said absorber and evaporator, a motor fan unit for circulating the mediums in said apparatus, said motor fan unit including a lubricant ,reservoir and a vent connecting the top of said reservoir to said inert gas circuit, said apparatus being so constructed and arranged and the connection to the various vessels being such that liquid contained in any vessel except said lubricant reservoir may flow to another vessel bypassing the motor i'an unit regardless of the position in which said apparatus may be placed.

11. An absorption refrigerating apparatus comprising, a plurality of vessels including, a generator assembly, a condenser, an evaporator, an

absorber, a solution reservoir, 9. closed solution circuit including said generator assembly, reservoir and absorber, a closed inert gas circuit including saidabsorber and evaporator, a vent connecting the top of said reservoir to said inert gas circuitand amotor fan unit for circulating the mediums in'said apparatus, said motor fan unit being 50 positioned that its center substantially coincides with the volumetric center of said apparatus and the connections to the various vessels being such that liquid contained in any vessel may flow to another vessel by-passing the motor fan unit. I

12. In combination, an absorption refrigeratin.

said casing cannot spill from said casing regardapparatus and a motor fan uni for circulatir:

a,4oo,a14 the mediums in said apparatus, said motor fan unit being so arranged relative to the other parts of the apparatus that the volumetric capacity of the apparatus on either side of any plane cutting said motor fan unit exceeds the total volume of liquid contained in said apparatus.

13. In combination, an absorption refrigerating apparatus and a motor fan unit hermetically sealed in the walls of said apparatus for circulating the mediums therein, said motor fan unit being so arranged relative to the other parts of the apparatus that the volumetric capacity of said apparatus on either side of any plane cutting said motor fan unit exceeds the total volume 15. A refrigerating apparatus including a fluid pump hermetically sealed to the walls of said apparatus, said apparatus being so constructed and the parts of said apparatus so arranged relative to each other that the center of the pump is positioned substantially at the volumetric center of said apparatus and that the volumetric capacity of the apparatus on either side of any plane cutting said pump exceeds the total volume of liquid in said apparatus.

16. A refrigerating apparatus including a fluid pump, said apparatus being so constructed and the parts of said apparatus so arranged relative to each other that the center of said pump is positioned at substantially the volumetric center of said apparatus, that the volumetric capacity of the apparatus on either side of any plane cutting said pump exceeds the total volume of liquid in said apparatus and that liquid can flow from any part of said apparatus except said pump to any other part without flooding said pump.

17. An absorption refrigerating apparatus including a motor fan unit for circulating the mediums in said apparatus, said apparatus being so constructed and the parts of said apparatus being so arranged that liquid can flow from any part of said apparatus except said motor to any other