US 2544394 A
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arch fi, 19H MUFFLY 2544,34
REFRIGERATOR WALL AND CLOSURE Filed Dec. 7, 1945 4 Sheets-Sheet l Zemyz a ff? ATTORNE Yfi March 6, 1951 Filed Dec. 7, 1945 G. MUFFLY REFRIGERATOR WALL AND CLOSURE 4 Sheets-Sheet 2 ATI'I'ORNEVSQ March 6, 1953 cs. MUFFLY REFRIGERATOR WALL AND CLOSURE 4 Sheets-Sheet Filed Dec. 7
March 6, 1951 G. MUFFLY REFRIGERATOR WALL AND CLOSURE 4 Sheets-Sheet 4 Filed Dec. 7, 1945 I N V EN TOR. GZe/YH M Patented Mar. 6, 1951 UNITED STATES PATENT OFFICE REFRIGERATOR WALL AND CLOSURE Glenn Muflly, Springfield, Ohio Application December 7, 1945, Serial No. 633,371
11 Claims. 1
This invention pertains to refrigeration and particularly to mechanical refrigerators adapted for household use and is a division of my application for Letters Patent of the United States for Improvement in Refrigerator filed October 3, 1941 and Serially numbered 413,495, now Patent No. 2,410,672 issued November 5, 1946.
One of the objects is to provide a self-opening and self-closing outer door.
Another object is to provide operating means for such a door, employing spring means which acts at one time to open the door and at another time to close the door.
An additional object is to provide a door or cover for an inner receptacle of such a refrigerator which is self-closing as a result of closure of the outer door.
A further object is to provide a new type of frame or breaker strip for a refrigerator door or the opening which it is adapted to close, such nonconducting frame being molded in place in one piece.
Another object is to provide for assembly of inner and outer metal walls of a refrigerator or its door with suitable insulation between such walls, the metal walls being tied together in a manner to hold the insulation compressed and to obviate the necessity for adding a frame to provide structural strength.
Still another object is to provide a freezer door inside of the refrigerator with latch means effective both for securing the freezer door closed and for breaking an ice bond between the freezer door and the freezer walls.
An additional object is to provide a refrigerator door with a latch which does not project forward farther than the door itself, thus simplifying the packing of the refrigerator for shipment and eliminating the use of a projecting handle or other part which might catch on a persons cloth- A further objectis to arrange the internal enclosures of a refrigerator in a manner to provide better visibility of articles placed on shelves located below such enclosures.
Another object is to provide a removable shelf or tray for use within the main food compartment of the refrigerator or within the freezer compartment interchangeably.
An additional object is to provide a multipletemperature cooling system employing two or more evaporators adapted to be cooled to different low temperatures and to provide in addition a dryer coil adapted to serve as an additional evaporator connected in series after which ever evaporator is active.
A still further object is to provide for the automatic removal of water condensed from the air within the refrigerator and for draining all such condensate through a common outlet to a readily cleanable condensate evaporator outside of the refrigerator.
Still another object is to provide for location of the door operating mechanism within the refrigerating machinery compartment of the refrigerator.
A still further object is to provide an evaporator within the refrigerator with extended surfaces which are so formed as to drain any moisture collected thereon into a moisture-collecting pan without the necessity for locating such a pan so that it interferes with the circulation of air over the evaporator and its extended surfaces.
The accompanying drawingsv illustrate only one dcsign without going into modificationsexcept that Figure 7 shows an alternative type of latch for the freezer door. In these drawings similar reference numbers are used for similar parts throughout, and all figures except Figure 7 are tied together by the broken lines which indicate where sectional views are taken or are enlargements of other figures.
Figure l is a front elevation of the refrigerator,
showing the outer door broken away, the freezer door removed and the ice-water tank removed for a clearer showing of internal parts.
Figure 2 is a sectional view of Figure 1 taken on line 2-2 thereof, showing the ice-water tank in position and illustrating the method employed to reclose the cover of this tank. This view also shows a section of the half mold used in forming the door frame from plastic material.
Figure 3 is a horizontal sectional view of Figure 1 taken mainly on the line 33 thereof and including broken portions. This view shows the spring devices for actuating the outer door and for reclosing the ice-water tank cover. It also shows details of the main door latch and its connection with the door closing mechanism.
Figure 4 is a detail sectional view of Figure 1 taken on the line 4.4 thereof to illustrate the relationship between the hinge rod of the outer door of the outer panel immediately below the door.
Figure 5 is a sectional view taken on the line 5-5 of Figure 1 to illustrate the relationship of the hinge rod to the door and to the cabinet and further to show sections of the molded door frame and of the molded frame for the door opening,
illustrating the change of section of these frames on the hinge side of the door as compared with the sections seen in Figures 2 and 3.
Figure 6 is a detail view of the freezer latch as seen from the line 6-6 of Figure 1.
Figure 'l is a fractional horizontal sectional view of the freezer and its door, showing a modifled form of latch.
Figure 8 is an enlarged sectional view showing a part of Figure 3 in greater detail.
Figure 9 is a detail of Figure 3 showing the door spring mechanism with door partially open.
Figure 10 is similar to Figure 9, but showing the door fully opened.
Figure 11 is an enlarged detail view showing the part of Figure 2 which includes the spring and latch means for the cover of the ice-maker tank.
The cabinet I is fitted with a door 3 adapted to open the full front of the food space. The door is attached to the hinge rod 4 which is connected with a spring-actuated mechanism for both opening and closing the door, as below described.
The rod or shaft 4 carries a collar 5 which engages the bottom support bearing 6 in end thrust to support the weight of the door and the upper end of rod 4 has its bearing insupport I. At the left side of the door, as seen in Fig. 3 the hinge 8 supports the latch plate 9 which is pushed inwardly toward the cabinet to release the door.
This moves the push rod I0 inwardly, moving the latch lever II in a counterclockwise direction together with the shaft I2, as viewed from above, thus withdrawing the hinged latch end I4 from engagement with the door, with is thereupon opened by the door spring I6. This spring is supported at one end by the fixed member I8 and acts upon the lever 20, which is secured to the hinge rod 4. This hinge rod is in turn secured to the outer wall member of the door, being free to rotate in bearings 6 and I. Since the spring [6 is under tension when the door is closed, it acts in an opening direction on the door while the lever 20 moves through the angle a. The inertia of the door will thereupon stretch the spring I6 while the lever 20 and the door move through a slightly lesser angle, as seen in Figure 9 and indicated at b in Fig. 3, bringing the lever 20 to the position 20'. At this point thepawl 22, which is also secured upon the rod 4, has engaged the notch 23 of the ratchet quadrant 24, thus holding the door open with the spring l6 partially extended.
It will thus be seen that a user coming to the refrigerator with both hands full can open the door by merely touching the striker plate 9 with her elbow. While the door does not open wide, it
opens far enough to provide ordinary access to the food compartment and it may be pushed to the 90 position of full openin (Fig. 10) without using the hands. When the door is so pushed the pawl 22 is moved into engagement with the second notch 25 in the quadrant 24. The lever is at the same time moved to the dotted position 20", further extending the spring I6.
To close the door from this full-open position it is only necessary to again depress the Plate 9. which causes the shaft I2 to move counterclockwise as seen in Figs. 3 and 8, carrying with it the lever 21 and through the medium of pull-rod 29 moving the quadrant 24 away from the pawl 22. The plate 9 should preferably be held in its depressed position until the pawl 22 has passed the notch 23, then released before the door has fully 4 I closed, but the notch 23 is so formed that failure to do this will not prevent closing of the door. It will be noted that the angle 0 plus b is considerably greater than the angle a, hence the energy stored up in the spring [6 when the door is at its full-open position will impart suilicient momentum to the door to carry the lever 20 through the angle a and thereby load the spring I6 under tension with suflicient energy for reopening the door as above described. This mechanism is accessible through the opening closed by the unit compartment door 30.
As the door closes it engages the latch end I4, which is hinged upon the latch lever II in a direction to allow the door to close without moving the lever II and its associated parts. The hinge joining II and I4, is of a one-way type and provided with a spring acting to hold the part I4 in the position shown, with its arcuate end engaging the notch in the striker on the door. By means of a suitable angle and location of the notch surface, the latch end I 4 is stopped by contaot on its arcuate end rather than on one side, thus holding it slightly out of line with the lever II, canted at an angle so that it holds the door securely closed. This angle is enough to allow for wear, but not enough to impose an excessive toggle load on the depression of the plate 9 for the next opening of the door.
The spring 3| is attached to the rod 29 and to a fixed support on the cabinet so as to be under some tension. It holds the lever 21 against its stop 32, thus establishing the normal position of the plate 9. the lever II and the quadrant 24. The spring 3| is located so as to pull at an angle upon the rod 29 and thus keep this rod from vibrating. The quadrant 24 is pivoted on the horizontal wall above the machinery compartment of the cabinet in a manner to allow the lever 20 to swing freely below it.
The notches 23 and 25 and the end of the pawl 22 are rounded or given a negative rake. This is not a great enough rake to allow the spring It to overcome the spring 3|, but is sufiicient to prevent injury to the parts in the event that the user forces the door in a closing direction instead of touching the plate 9. It is preferred that the negative rake of the notch 23 be greater than the negative rake of the notch 25, both because this notch has less sprin tension to hold and so as to allow the user to push the door -closed from its two-thirds open position without touching the plate 9.
The metal walls of the cabinet structure housing these latch parts are held apart by wood blocks 34 and tied together by Wire ties 35, as seen in Figure 8. The hinge rod 4 passes outside of the welded joint between the right-hand outer sheet 31 of the cabinet and panel 38 below the door, as seen in Figure 4, but its lower end is concealed behind the unit compartment door 30. Panel 38 may be one piece with the sheet of metal below the bottom insulation, as shown, to reduce the length of joints to be welded. The door 3 may be removed from the cabinet by removing the door 30, disconnecting the spring I6 and lever 20, loosening the lower support 6 from the cabinet, opening the door and droppin it down to withdraw the upper end of the rod 4 from its support I.
The freezer 40 is similar to one shown in my co-pending application, Serial No. 237,629, filed October 29, 1938, now Patent No. 2,359,780 granted October 10, 1944. It will be understood that the means for closing the freezer door disclosed in this prior application may be employed in connection with the present disclosure. A difference between the freezer and tank arrangement of the present application and that of the earlier application last mentioned above is that I have made the freezer wider and the ice-maker tank narrower. This is done to improve the visibility of the interior of the cabinet, particularly portions of shelves located below the ice-maker tank. The arrangement here shown places the ice-maker and the freezer in an inverted pyramid arrangement whereby the user is given an angle of vision which allows a clear view of the major portion of the food storage space.
The freezer 40 is an insulated enclosure which may be considered a small refrigerator within the main refrigerator. Closing of the outer door 3 causes it to engage the bumper 4| of rubber or other suitable material, thus closing the insulated door 42, the latter being hinged at the right and fitted with a special latch which serves not only to hold the freezer door closed, but as a means for prying the door free when it is frozen shut. A freezer of this type should be held at a temperature considerably lower than that of the main food compartment and the latter should be held at a temperature above freezing with a high relative humidity. The air of the main food compartment of the refrigerator will therefore contain enough moisture to fall below its dew point at the junction of the freezer door and the fixed freezer walls. This causes frost to collect in the door joint, freezing the door shut. When the freezer door is opened after being closed for a considerable period it is necessary to break the ice thus formed, hence I have provided means for doing this.
Figure 6 is a fractional view showing a side elevation of the latch as it'would be seen from the left as indicated in Figure 1. The freezer 46 is closed by the hinged door 42, this door having rigidly attached thereto the latch plate or striker 43. When the door is pushed shut this striker engages and lifts the latch member 44, this latch or pawl being returned by the spring 45 to secure the door in its closed position. To open the latch the lever 46 is moved in the direction of its dotted position 46' and the lug 41 lifts the latch 44 clear of the striker 43 so that the door may be opened. The cam surface 48 which is integral with lever 46 and located below lug 41 engages latch plate 43 and forces the door open after latch 44 has been lifted clear of striker 43. Since the spring 45 is retained between the latch body 49 and the latch member 44, while the latch member engages 8 l door as disclosed in my application. Serial No. 237,629 filed October 29, 1938, the rubber bumper 4| finally pushing the door 42 closed .to its latching position.
The insulating material for cabinet walls is preferably in board form or semi-rigid packages. This insulation is placed within the outer shell of the cabinet and then the cabinet liner is pushed into place. The blocks 34 of wood or other material, preferably having a low thermal conductivity but being substantially non-compressible, are forced into place between the edge of the liner and edge of the outer shell. as seen in Figures 2 and 5. Wires 35 are then tied or welded in place to hold these edges in position and secure the blocks 34.
The freezer bracket 50 supports the freezer 46 while evaporator supports 5| and 52 depend from and are supported by the freezer. It will be noted that the support 52 is provided with a drip point 53 to insure that condensation formed on 52 or does not fall upon food placed in the lower right-hand portion of the cabinet.
The ice and water tank 55, which will be understood by reference to my several issued patents showing similar tanks used for making ice and storing it in flotation, is provided with a cover 56 and a faucet 51. The ladle 56 for dipping ice from the tank is provided with a hook 59 upon which it normally hangs. The tank rests upon andis refrigerated by the evaporator 60, thus forming ice blocks 6| from a portion of the water the lug 41, it will be seen that the spring not only moves the latch down against the lug 41 but thereby moves the lever 46 forward to the posi-.
tion indicated by full lines in Figure 6. The purpose of cam 48 is to break any ice bond which may have been formed between the door 42 and the body of the freezer 46. One continuous movement of the lever 46 rearwardly first lifts the latch and then forcibly pushes the door open far enough to break any ice bond. In order that the door 42 may be slammed or pushed closed without danger of damage that might result from inertia of the lever 46 I have provided for movement of the latch 44 independently of the lever 46 in an upward direction. The parts 44 and 46 are pivoted upon a common pin but not attached together except that the lug 41 on the part 46 provides a positive means for lifting the latch 44.
With either type of latch, the freezer door is automatically closed by the closing of the outer 62. The evaporator is preferably formed of sheet metal and provided with a number of raised spots 63 which contact the bottom of the tank 55 for the purpose of refrigerating separated areas of the tank wall so that ice may be formed thereon and periodically released to float in the supply of water 62 which is stored in the tank 55.
The ice discs 6| are released to float in the water during each idle period of the evaporator 66, in accordance with the method disclosed in my several issued patents, particularly No. 2,145,773. The tank is provided with a cover 56 which can be lifted and pushed back to the position shown in Figure 2.
When the cover isopened, ice blocks 6| may be scooped out by means of a perforated spoon or ladle 58 which is shown in Figure 2. The handle of this ladle is provided with a hole so that it can be hung upon the hook 59 seen at the upper righthand corner of Figure 1. The handle extends beyond this hole in a curved form so related to the curvature of the cabinet lining that the ladle can be hung on the hook in only one position. Thus no water can drip from the ladle onto food in the lower part of the refrigerator. The ladle preferably hangs clear-of the cover 56 so that the cover may be opened while the ladle is in place and the ladle may be rehung upon its hook before the ice-maker tank cover is reclosed. This provides for allowing the ladle to hang in its position when the tank cover is opened merely to replenish the water supply. It will be noted that the tank extends considerably forward of the freezer door 42 and that the space above it in front of the freezer is clear when the door 3 is opened.
The cover 56 of the ice-maker tank is adapted to be opened by raising at the front and pushing rearwardly as shown in several of my issued patents, particularly No. 2,145,775 issued Jan. 31, 1939. In the present application I show an automatic mechanism for re-closing the tank cover, since it has been found that users sometimes neglect to do this. The wire 64 leads through the the tank cover.
customary door-operated switch to lamp 85 below drip collecting pan 86. This pan drains into trough 68 and catches drip from the outside of the freezer with the aid of baffle I0. Drain tube 12 leads from trough 68 to the drip-evaporating channels I3 on condenser I4, seen in Figure 1. The condenser is carriedby supports I5 and discharges liquid refrigerant through tube 16 to the evaporators located within the cabinet and vaporized refrigerant is withdrawn through tubes I1 and 18, I1 leading from an evaporator in the freezer 48 to be described later herein and I8 leading from the ice-maker evaporator 80.
To facilitate packing of the refrigerator without the bad practice of putting screws into the back of the cabinet and thereby endangering the air-tightness of the outer wall, which is necessary to maintain the insulating material in good condition, I have provided the holes 19 in the parts I5. Suitable screw hooks or bolts may thus be used to hold the refrigerator securely against the back of the packing case.
The cover 56 is provided with a handle 80 for lifting it, whereupon the cover is tilted upward against the freezer 40, which hasa beveled portion 82 to allow clearance for a wider opening of Attached to the cover 56 by means of ears 84 is a rod 86 which slides within the tube 81, both being surrounded by the compression spring 88. The tube 81 is provided with a collar to act as a stop, the tube being freely fitted within a hole in the upper portion of the bracket 90 which is removably attached to the tank 55 by means of support 9|. As the cover is pushed rearwardly the spring 88 is compressed to provide energy for re-closing the cover.
At the rear extremity of the cover 56 there is a rib 92 formed by embossing the metal of the cover or by adding a part to it and this rib is adapted to engage the ears 94 of the bracket 90, these ears being notched to receive the rib 92. The forms of the rib and of the notches are such that the cover is retained in its open position against the action of the spring 88, but this anchorage may be broken by a slight forward movement of the cover, whereupon the spring 88 acts to close the cover.
The required push for initiating the spring closing of the cover is provided by means of the rocker 96 (seen in Figs. 3 and 11), which is pivoted on the lower wall of the freezer 40 at 91 and connected with the push rod 98, which extends forward through the front vertical wall of the drip baiile I0 and is capped by the rubber bumper 99, adapted to be engaged by the inner wall of the cabinet door 3.
When the door is closed the button 99 is in contact with it and the rod 98 is thereby pushed to its rearward position, compressing the spring I 80. When the door 3 is opened this spring moves the rod 98 forward and the rocker 96 is thereby moved counterclockwise until it is stopped by contact with a suitable stop or with therear wall of the cabinet. If the ice-maker tank cover 56 is not opened, the reclosing of cabinet door 8 merely recompresses the spring I00, but if the cover 55 has been opened it is given a slight forward push by the lever 9'0 when the cabinet door is closed, thereby allowing the spring 88 to complete the closing of the cover 56.
The tank 55 is removable from the cabinet without disturbing any of the operating mechanism. After the tank is removed, as for washing, the cover 56 may be readily removed from the tank, whereupon the rod 86 is withdrawn from animus the tube 81 and the spring 88 is free. The tube 81 is freely removable from the bracket 80, since it is retained in position by the spring only, and the bracket '98 may also be removed from its support 9| on the tank. Since the rod 88 is required to move side-wise slightly with the movement of the lever 96 its rear support I82, which retains one end of the spring I88, is provided with an oversize or elongated hole to allow such movement.
The drawer I04, seen in the bottom of the cabinet, is arranged to slide within the cover or enclosure I05. Since the main food space of the cabinet is maintained in a high humidity condition because of being cooled by the exposed walls of the tank 55, by the non-frosting exterior walls of the freezer 40, by the periodically defrosted evaporator 60 and by a finned coil, none of which is continuously frosted, it is not necessary that the drawer I04 be made particularly air tight, though this may be done if it is desired to maintain the drawer at a still higher humidity than that of the main food compartment.
The shelf I0! is of L form and of such proportions that it may be inverted to hang in the position indicated by I81 or it may be placed on top of the housing I05, as indicated by the dotted lines I01". This latter position of the shelf is merely to provide for storing it out of the way when it is desired to place some bulky object in the large space at the left of the drawer I84.
The shelf I08 is of U form so as to provide a double shelf and prevent articles placed on its lower horizontal portion from sliding ofi. An additional shelf I 89 is provided near the upper left-hand corner of the cabinet and preferably arranged so that it may be hinged to the position shown by dotted lines. This shelf is particularly useful for the storage of butter, since this corner of the refrigerator will be maintained at a somewhat higher temperature than the lower portions. It is desirable that butter for current use be stored at a higher temperature than is best for other food stuffs, and this refrigerator is designed to provide the desired higher temperature space without the use of heating or heat leakage means such as are resorted to in some present models.
The basket I I0 is attached to the door 3 of the cabinet and swings with it so that the front upper portion of tank 55 is accessible when the door is opened.
The base I 12 of the cabinet, seen in Figure 2, is set in at the front to allow toe room and for entry of air between it and door 30, as indicated by the arrow. The base II 2 may also be set in at the sides of the cabinet to allow it to be placed closer to a wall on the right or left side. Removable corner pieces I I3 may be furnished to fill the sides of the base so that the user may remove one to clear a quarter-round and set the cabinet closer to a wall, or may leave it on for appearance. This inset base and the corner pieces are also helpful in packing and moving the cabinet without damage.
The tank I I5 is nearly filled with eutectic freezing solution I I6 which is normally held in a frozen or nearly frozen condition.
In addition to providing the freezer with an adjustable shelf ill, I have provided means for facilitating the transfer of food stuffs contained in small dishes between the freezer and the main food storage .compartment of the refrigerator as well as in and out of both. The tray or salver I20, preferably of glass, is designed to fit closely within the freezer and also to fit in a fore-and-aft 9 slightly less than'the inside depth of the main food compartment, so that the tray will just go into the freezer while it provides somewhat more clearance for air circulation when placed in a fore-and-aft position on one of the shelves of the main food compartment.
If desired, the tray may be designed with an extending flange or with straight sides and made of the correct length to be supported by the ribs which normally support the shelf II! in the freezer. Such a modified tray, adapted to serve as a removable shelf, is shown in place in the freezer in Figure 1 and identified as I22.
The plastic material I23 whch aids the gasket I24 in effecting a substantially ar-tight seal around the door is molded in place by the use of a mold form on the order of I25, which is clamped against the cabinet to form a substantially tight fit, as seen in Fig. 2. The plastic material I23 is poured or forced into the space defined-by the outer metal wall, the liner, the insulating material and the mold form I25 through the sprue I26,
I which may be in multiple, includ ng one or more risers or-vents to insure complete filling of the cavity with the plastic material. The mold form I25 is provided with cores I21 and I20 which may be used to circulate hot or cold fiuds as required to heat or cool the plastic material to expedite its hardening or to form a hard skin on its exposed side next to the mold form. The drawings are section lined to indicate use of a rubber compound, but it is to be understood that any suitable plastic material may be used.
A mold half similar to I25, but of femal form to receive the door 3, is used in like manner to cast the plastic frame or breaker which joins the inner and outer metal walls of the door and seals the insulating material between them. It will be noted that blocks 34 are not required on the door, but the wires 35 are used to secure the metal walls of the door together after assembling them with the insulating material between, preferably in a press which holds these metal walls together while the wires are tied or welded. The door thus assembled is then placed in the mold form and the plastic material injected as above described.
It will be noted that the angle of the contact surfaces between the door and the cabinet walls is different on the hinge side of the door as compared with other sides of the door. These surfaces blend into each other at the corners of the door adjacent to the hinge and all of the corners are rounded. The object is to form a smooth door frame in the cabinet and a smooth frame on the door itself, each of these frames serving the triple purpose of a frame, of a seal connect ng-the inner and outer metal walls in an air tight manner, and of a compressible contact surface to minimize air leakage when the door is closed. These contact surfaces are at d'fferent angles relative to the cabinet walls at different sides, as above described, but preferably they approach uniformity with respect to the ax s upon which the door swings. The contact areas are modified from the conventional form in order that each of these surfaces may approach a plane radial with respect to the axis of the door hinge. This provides for bringing the surfaces together with the minimum of slippage relative to each other. The plastic material is preferably such as to provide a smooth, tough skin where exposed and where the two plastic frames make contact. One or both of the plastic frames is preferably soft enough to be slightly compressible for the purpose of im proving the air tightness of the joint between them when the door is closed.
This construction eliminates the use of the usual breaker strip with its attendant joints and corner pieces. Being molded in place, the plastic frame itself provides both the seal for the insulation and the finish around the door and around its opening in the cabinet. It further provides two pairs of mating annular gasket surfaces for better sealing of the door when it is closed. The
exposed plastic surfaces are preferably so.
rounded and smooth as to minimize their tendency to collect dirt and to make it easier to wipe them clean.
The refrigerating system empoyed in cooling this cabinet includes a motor-compressor unit I30, preferably of the sealed type, which delivers compressed refrigerant vapor through tube I3I to the condenser 14. The liquid line I32 leads to the ice-maker evaporator 60. The wire I33 leads from the power source to the motor of I30. The liquid line 16 leads into heat exchange relation with the suction line' 11 and thence to the expansion device I35, which is associated with the valve mechanism I 31. This valve mechanism is similar to Figure 1 of my co-pending appication No. 346,085, filed July 18, 1940, now abandoned. except that I have here shown the expansion device as a separate assembly.
The valve assemb y'ijill distributes refrigerant liquid to cool the ice-maker or the freezer, one
. at a time and the suction vapor from the active evaporator passes through the valve assembly I31 to the drier coil I38 and thence through suction tube 11 back to the compressor of unit I30. The coil I38 is equipped with fins I39, as seen in Figure 1.
The valve mechanism I31 includes an element which acts in response to changes o evaporator pressures to actuate a valve controlling the-flow of vapor from the warmer evaporator 00 to the suction line 'Il,,a liquid valve controlling the flow of refrigerant to the colder evaporator, and the switch I 40. The assembly I 31 also includes a check valve through which suction vapor passes from the colder evaporator as it enters the assembly I31, and a check valve through which liquid refri erant flows from the expansion device I35 to the inlet of the warmer evaporator 60.
The cycling of the system is as follows: When the unit I30 is idle, a pressure rise within the colder evaporator causes the opening of the valve which controls the passage of vapor from the warmer evaporator to the dryer coil I38. In the event that the warmer evaporator reaches its preselected maximum pressure prior to the time that the coder evaporator reaches its preselected maximum pressure, the higher pressure in the warmer evaporator acts directly to unseat the valve which controls the flow of vapor from the evaporator 60 to the dryer coil I38.
In either case the higher pressure of the warmer evaporator thus becomes effective upon a bellows which actuates the switch I40, thus closing the circuit which starts the operation of the motor-compressor unit I30 and refrigeration is thus started in the warmer evaporator 60 associated with the ice-maker tank. As refrigeration proceeds and the temperature of the evaporator 60 falls, the suction pressure is thereby reduced and the bellows orother pressureresponsive member moves in the'direction of reclosing the valve in the assembly I3! which controls the passage of vapor from the evaporator 60 to the dryer coil I38. As this valve nears its closing point with .the compressor continuing to operate, there is a. rapid drop of pressure in the suction tube I1 and evaporator I30. This reduction of pressure causes a further flexure of the pressure-responsive element, which is on the downstream side of the c osing valve. Such action on the pressure-responsive element eifects a complete closing of the valve and there is a further drop in the suction pressure until it reaches the point where the lower pressure vapor in the colder evaporator lifts the check valve which controls its admission to the assembly I31, to the pressure-responsive element and byway of the dryer coil I38 to the suction line IT. The system now operates to cool the colder evaporator in the freezer and the evaporator I38. This operation continues until the evaporating pressure in the colder evaporator has fallen to its preselected minimum, at which point the pressureresponsive element causes the switch I40 to open, thus stopping the operation oi the unit I30.
As will be seen in Figure l of the prior application last mentioned above, there is a check valve arran ed to allow flow of liquid refrigerant from the expansion device to the warmer evaporator and there is also a valve controlling the flow of liquid refrigerant from the expansion device to the colder evaporator. This second valve is mechanical y opened coincidentally with the closin of the pressure-actuated valve in the passage between the warmer evaporator and the dryer coil I38.
The check valve in the suction passage leading from the colder evaporator is for the purpose of preventing warm re rigerant vapor flowing from the warmer eva orator to the colder one. Likewise the check valve between the expansion device and the warmer evaporator is to prevent flow of refrigerant from the warmer evaporator to the colder evaporator through their liquid connections with the valve assembly I31. The valve controlling flow of linuid from the assembly I31 to the colder evaporator is c osed whenever the warmer evaporator is operating so as to prevent liquid refrigerant from flowing into the colder evaporator at that time.
The dryer coll I38 is provided with fins I39 having their lower ed es cut at an angle. The fins may be of paral elogram shape as shown, or may have some other shape at their upper ed es, but the lower ed e is inclined so as to provide a drip point whereby any condensate collected thereon will drip into thepan 66. It will be noted that the valve assembly I31 and a l of the connecting tubes are likewise arran ed so that condensate will drip from them into the pan 66. In order to provide for collection of condensate from the outer surface of the freezer 40, a drip baflie I is arranged below the side of the freezer which extends bevond the drip nan 66.
The tube 78 is preferably not a so-called capillary tube, but is a tube of sma ler inside diameter than the usual liquid line. This small diameter liquid line does not restrict the flow of liquid refrigerant to the extent of causing it to be cooled by its own expansion, since that would defeat the purpose of the heat exchanger. On the other hand the inside diameter of the liquid tube I6 is small enough so that there will be a clean drainage of liquid refrigerant from it and the bottom of the condenser, which would not occur if the inside diameter of the liquid line were large enough to allow vapor bubbles to pass drops of liquid within the liquid line. At the end of an operating cycle all of the liquid within the condenser is pushed up through the tube I0 and the expansion device I36 into the low pressure side of the system. This relieves the motor-compressor unit I30 of the high pressure on its discharge side and allows for the use of a splitphase motor without providing any additional mechanism for unloading the compressor. While this eifect could be obtained if the tube 18 were either of a capillary size or of the usual liquid line size, there would be a loss of efllciency in either of these cases.
If the liquid line which forms a part of the heat exchanger were of capillary size the object of the heat exchanger would be defeated, due to the high linear rate of flow through the capillary.
tube and because of the fact that partial evaporation of the liquid within the capillary tube cools the liquid by wasting some of its own refrigerating eil'ect instead of by giving up its heat to the cold suction vapor. On the other hand if the tube I0 were of large enough diameter to allow liquid and vapor to pass each other within the tube, we would have this condition at the end of an operating period: There would be a quantity of liquid within the liquid line as the compressor stops and this liquid would run down in the tube while vapor from the condenser would pass through the capillary device I35. The liquid remaining in the bottom of the condenser and in the liquid line would then have to evaporate outside of the refrigerator and pass through the capillary device I35 in its vapor phase, thus carrying heat from the room into the refrigerator.
The control switch I40 which is connected with the motor of unit I30 through wire I is provided with a lever I42 designed to close the switch upon downward movement. By means of the rod I43, which is slotted at its upper end to allow some free movement of the pin located in the crank I44, a lost motion connection may be made between the lever I42 and the shaft I45. This shaft is fitted at its forward end with the handle I46. Clockwise rotation of the handle rotates shaft I45 against the resistance of the torsion spring I", thus moving the arm I44 and after taking up any lost motion this movement opens the valve which admits vapor from the evaporator 60 to the dryer coil I38 and the suction line H, then closes the switch so that the system starts operating to cool the ice-maker evaporator 60 and the evaporator I38.
The lamp 65, seen in Figure '1, is connected to one side of the power line I48 and through the wire 84 to the opposite side of the line. One of these wires is provided with a switch, which is indicated in Figure 1 but not described in detail. This switchis closed by the opening of the door and reopened when the door is closed by means commonly used in household refrigerators. The wire I33 from the current source leads to the motor of the motor-compressor unit I30 while the other line I40 from the current source leads to the switch I40 and to one side of the lamp 65.
The opposite pole of the switch I40 is connected by means of the wire III with the other pole of the motor in the conventional manner. The motor-compressor unit I30, is mounted on rubber blocks or otherwise flexibly supported, as indicated in the lower portion of Figure '1, and includes a relay switch or starting circuit breaker, as usual.
The eutectic tank 5 is nearly filled with the eutectic freezing solution IIB, leaving room for expansion when the solution freezes. This is-a solution which freezes at a low temperature, preferably about F. The quantity of the eutectic solution and its latent heat of fusion are such as to provide a substantial hold-over of refrigerating effect so that the freezer is maintained at its desired low temperature when the system is idle for a considerable length of time, as in a cold room.- Liquid refrigerant is conveyed through tube I50 to evaporator coil I! when the valve mechanism I31 has assumed the required position as above described to refrigerate this coil, the vaporized refrigerant flowing through tube I52 to the valve mechanism I31 and thence through coil I35 and suction tube 11 back to the motor-compressor unit I30. During operation of the evaporator coil IS! the eutectic solution freezes upon this c oil, first at the bottom of the tank H5, since the refrigerant flows first through the lower legs of the coil I5l. This method of freez ng an eutectic solution from the bottom up wardly is covered in my issued patent, No. 1,827,097. Another fact contributing to the holding of a constant low temperature within the freezer 40 will be understood upon consideration of the method of operating the switchllfl and the valve mechanism I31. These mechanisms provide for starting refrigerating effect in the evaporator |5| whenever its temperature rises to a predetermined limit, regardless of what temperature may obtain within other portions of the refrigerator. This switch and valve mechanism are more fully described in my Patent No. 2,375,319 and my application S. N. 477.519 of which the original was filed July 18, 1940, now Patent No. 2,425,634 granted August 12, 1947. This system of control provides for starting operation of the system whenever either the freezer evaporator or the evaporator .which cools the main food compartment of the refrigerator rises to its cut-in temperature. Refrigeration is thus supplied where needed instead of being controlled by a compromise method in response to some temperature between that of the main food space and that of the evaporator which cools the freezer or low temperature section of the refrigerator.
Since dew forms upon the outside of the tank 55 and fro t forms upon the evaporator 60, this frost being periodically melted during idle periods of the evaporator, I have provided the drip collecting pan 66 to collect the water thus deposited.
The pan 66 is provided with one or more openings for draining such Water into the trough 68 100 ted below it.
Moisture will also condense on the outer walls of the freezer 40. Mo t of this water will drain down o er the tank cover 55 into the pan 56, but an addit onal drip baffle is provided to catch the moisture draining from that portion of the exter or surface of the freezer extending to the left of the ice-maker tank and deliver it to the drip pan 65. Thus all moisture collecting on expo ed cooling surfaces within the refrigerator will finally reach the trough 58 and be drained out the back of the cabinet through the tube 72 to the condenser 14 on the back of the cabinet and be thereby re-evaporated to ambient air. Thi method of drip dissipation is more fully described in my U. S. Patent No. 2,145,776, issued Jan. 31, 1939.
In Figures 2 and 3 I have shown an improvement in the drip evaporator associated with the condenser 14. The drain tube 12 conducts water fr m the tro gh G8 to the upper one of the everal dr p c annels 13 which are formed integrally with the condenser 14, on its rear (outer) side. The condensate collected within the refrigerator flows from the uppermost of these channels 13 out its open left end as seen in Figure 3 into the channel 13 next below it and so on down the exposed side of the condenser. It has been found that in any ordinary operation of a refrigerator of this type, where the exposed cooling surfaces are either maintained above the freezing point or are defrosted at each cycle of the system, this type of drip evaporator will dispose of all condensate before any of it reaches the lowermost one of the channels I3. I
The advantage gained by forming this drip evaporator on the side of the condenser away from the cabinet rather than on the side next to the cabinet, as shown in my U. S. Patent No.
2,145,776, is that the channels 13 are thereby made readily cleanable.
There is a natural convection flow of air upward on both sides of the condenser, between it and the cabinet and between it and the wall against which the refrigerator is placed. In order to insure that the refrigerator is not placed too close to the wall, I have formed the condenser suppports 15 so that they extend rearwardly of the condenser to contact the wall against which the refrigerator is placed. It will be seen that I have extended the supports 15 upwardly considerably farther than the condenser. This provides a vertical fiue above the condenser so that when the refrigerator is properly placed against the wall of a room a flue is formed to provide an additional draft of thermal circulation drawing air from near the fioor over the condenser and drip evaporator. The column of air above the condenser is lighter than ambient air, both because it has been heated by passage over the condenser and because water vapor has been added to it by the evaporation of drip water, water vapor being lighter than air.
The common practices with respect to gaskets on refrigerator doors are either to let the door ga ket make contact with a flat surface such as the face of the cabinet and with step surfaces parallel with the face of the cabinet, or to have the gasket contact against angular surfaces which converge inwardly toward the center of the door opening at a uniform angle to the cabinet face on each side of the door. Both of these practices cause the gasket to slide upon its contacting surface, either at the hinge side of the door or at the opposite side, according to the practice followed. Unlike these common practices I have designed the contact surfaces of the door and of the cabinet so as to approach as nearly as is practicable to planes that radiate from the hinge axis of the door. This causes the door gasket, which in my case is a part of one or both of the molded breaker frames, to make contact with its mating surface without the objectionable sliding motion.
Both of the door frames, namely the molded rame of the door itself and the molded frame of the door opening, are formed, at least on the corners adiacent to the hinge side, with compound curves joining their contact areas. It will be seen that the contact surfaces of these frames may be in one plane at the latch side, the top and the bottom of the door, hence the junctions of these surfaces at the corners on the latch side of the door or of its opening may be in one plane and this plane will still be substantially radial with respect to the hinge axis of the door. In order that the contact surfaces of the frames on the hinge side may be substantially radial with respect to the hinge axis, these surfaces can not be in the same plane as the contact surfaces at the accuses top, bottom and latch side of the door, hence it is particularly at the corners of the door and of its opening adjacent to the hinge side of the door that these compound curves are required to provide smooth, continuous contact areas and have the door close with the minimum of sliding movement between contacting surfaces.
As will be seen from the horizontal section of the door in Figure 3, the axis of the door hinge is 50 located that the door will swing open to allow substantially unobstructed access to the interior of the refrigerator without swinging beyond the plane of the outer wall of the cabinet on the right-hand side. This and the absence of a projecting latch on the door allow the door to open fully when the cabinet is placed in a right-hand corner of a room without requiring any extra clearance space for the opening of the door.
The freezer 48 and its door 42 are preferably made with molded frames somewhat as described for the outer door of the cabinet, but it is not so important to provide the freezer door with gasket means, since heat leakage at this point aids in cooling the main food space of the refrigerator instead of representing a loss of refrigerating effect to the room as in the case of the outer door. Since the freezer door will normally be frozen shut when left closed for a length of time, there will be very little air leakage around the freezer door except for a limited period after each time it is open. This freezing shut of the freezer door is my reason for preferring to make the contacting surfaces between the freezer 40 and its door 42 of metal or of a harder-surfaced composition than is used around the outer door of the cabinet. A soft material, such as is preferred to provide some gasket effect around the outer door, might be damaged by the forcible opening of the freezer door when it is frozen shut.
The modified freezer door latch seen in Figure 7 includes body I1I, bolt I12 and spring I13, forming a conventional-spring latch of the selfclosing variety, which may be opened by means of the handle I14. The latch bolt I12 is arranged to slide within the latch body I'll against the action of spring I13 when handle I14 is pulled. I
have added an extension I15 to this handle, so formed that it engages striker plate I18 after the bolt I12 has been withdrawn from the striker plate. It is thus seen that the user need only pull on the handle I14 to first withdraw the bolt I12 from the striker plate and then to use the handle I14 and its extension I15 as a lever to pry the door open by breaking the frost or ice around it. This one pull on the handle I14 will further pivoted by means of the pin I83 to the push rod I0, which is in turn pivoted to the latch lever II by means of the pin I84. For convenience in assembly, the member ID is notched to receive the pin I84 as the assembly comprising parts II and I4 is inserted in the cabinet wall, whereupon the upper splined end of the rod I2 is inserted in the member II from below and suitably retained at its lower end to maintain the spline engagement. The shaft I2 is supported by bearings I85, which are secured to the sheet I82. The members II and I4 are hinged together by the pivot pin I86 and are urged into alignment with each other by means of the coil spring I81.
As the door 3 closes, the striker I88 engages the member I4, flexing the spring I81 so that the latch member I4 snaps into the position shown in Fig. 8 to retain the door in its closed position. The spring I81 is not stiff enough to cause such closing of the door to produce any material movement of parts II, I2, 21, 29, and 24 since their weight and the action of the spring 3| oppose such movement. It will be seen that the spring 3| (seen in Figs. 3, 9 and 10) urges the rod 29 to the right and this rod is pivoted at I89 to lever 21. The location of parts II and I4 is determined by the angular position of lever 21 when it en- 1gagtes the stop 32, which is attached to the cab- Spring 3I is attached to the rod 29 by means of the collar I98 and attached to the cabinet by means of support I9I.
. The main cabinet door, of which a fraction is seen in Fig. 8, includes an outer sheet of metal I and an inner sheet of metal I96. These two sheets of metal are separated by the compression members 34, as previously explained, and are tied together by means of wires 35. At the latch position on the door 3 it is permissible that the member I88 be welded or otherwise attached to both sheets I and I98. The section of member I88 may be reduced, or a member of low thermal conductivity interposed between I88 and one or both of the sheets I95 and I96, if desired to further minimize thermal conductivity between these two sheets. It will be noted that the greater portion of the part I88 is buried within the molded insulating material I23 in the same manner as the members 34 andwires 35 are buried.
It will be seen that the outer sheet I85 of the door 3 makes contact with the molded plastic material I23 of the cabinet wall, while the cabinet liner I98 makes contact with the molded material I23, which forms the frame of the door, thus providing a double seal. The part I8 may be a sufliciently close flt within the molded material I23 of the cabinet wall to substantially prevent circulation of air into and out of the space enclosing the members II and I4.
Due to the fact that the pivot I86 is not far out of line between the center line of shaft I2 and the point at which I4 contacts I88, the pressure of I 88 against I4, due to the force exerted by spring I8 urging the door in an opening direction, does not produce sufiicient force in a counter-clockwise direction upon the shaft I2 to move the lever 21 away from its stop 32. For this reason, the contours of contacting surfaces of I4 and I88 may be such as to allow for wear and still hold the door tightly closed, as previously explained.
It will further be noted that the path of the pivot I8; upon counter-clockwise movement of part I I is on an are having its center at the center of the shaft I2, thus the first movement of part II in a counter-clockwise direction moves the pivot I88 away from the surface of I88, which is contacted by the part I4. insures that the door is held snugly closed and yet allows easy movement of parts I I and I4 when manual contact is made with the plate 9. In Fig. 8 I have shown sealing contacts between material I23 of the door with the cabinet liner I98 and of material I23 of the cabinet with the outer metal sheet I95 of the door. In accordance with the description herein of. the shapes of these contacting surfaces, it is possible that it may be preferred to have the material I23 of the door make contact with material I23 of the cabinet at both This arrangement a the inner and outer contact areas. The choice will be governed to a large extent by production methods employed and the relative costs of the metal working dies of special contour and the permanent molds to produce the desired contours of the molded parts.
Fig. 9 may be considered as an enlarged detail of the lower ri ht-hand corner of Fig. 3, showing the position of the spring [6, lever 20 and pawl 22 when the door 3 is in its partially opened position, previously mentioned as the one to which the door swings when released by depression of the latch plate 9. The ratchet quadrant 24, pivoted at 2M upon the fixed member 202, is urged toward the pawl 22 by means of the spring 3|, its position being determined by the stop 32 and by 29 being linked to 24 by means of the pin 284. As the door swings open, due to the initial stress of the spring l6, force is released for reenergizing the spring is to the extent indicated in Fig. 9, so that the pawl 22 is retained in the notch 23 of quadrant 24 and the door stands open at an angle of approximately 60.
Should the user wish to have the door more fully opened, she pushes it open and the pawl 22 engages the notch 25 of quadrant 24, retaining the door in its fully opened position, as seen in Fig. 10. The spring I6 is now stressed to a greater degree than it was when the door was closed, so that when the user depresses the plate 9, thus moving the quadrant 24 out of engagement with pawl 22, the spring it causes the door to swing fully closed and be retained in that position by means of the latch member l4 engaging the striker I88. The user will naturally release the latch plate 9 just prior to the full closing of the door, so. as to allow the latch I4 to retain the door in the closed position.
Referring to Fig. 11, which shows an enlarged detail of Fig. 2, it is seen that the ears 84 on the tank cover 58 carry a pin 2H1 pivoting thereto the member M2 to which one end of the rod 86 is rigidly attached. Likewise, a member 2l4 attached to the end of the tube 81 forms the support and stop for this tube with reference to the bracket 90, which is supported on the tank by means of the support 9|. The left-hand end of the tube 81 is preferably tapered or chamfered, so as toallow free movement thereover of the coils of the spring 88. As the rod 86 slides within the tube 37 with movement of the cover 56, the spring 3% urges the cover 56 toward its closed position, but the cover is here shown open and is retained in the open position by means of its rib 92 engaging the cars 94 of bracket 90. The form of this rib, the form of the ears 94 and the position of the line of contact between the cover 56 and the tank 55 when the cover is open are so related to the pivot point 2H) and the action of the spring 88 that the cover will rest in the position shown in Fig. 11 regardless of the fact that the spring 88 is urging the cover toward its closed position.
In Fig. 11 we also see an end of the rocker 96 (seen in Fig 3), which is in position to make contact with the cover 56 upon a slight movement of the rod 98; When the rocker 96 contacts the cover 56 and moves it so that rib 92 is no longer retained by the notches in the bottom of the ears 94, the spring 88 acts to complete the closing of the cover 56 on the tank 55.
I claim as my invention:
1. A refrigerator, an outer door of said refrigv erator, a smaller enclosure within said refri erator, an access opening in said small enclosure,
a closure for said opening, resilient means tending to close said opening by means of said closure, latch means for holding said closure in an open position, and means actuated by the closing of said outer door for releasing said latch means and allowing said closure to close.
2. A refrigerator, a main food space within said refrigerator, a smaller insulated enclosure within said refrigerator, a. door for said inner enclosure, a door for access to said main food space and to the first said door, means for holding said inner door closed, and means for breaking an ice bond between the inner door and the fixed walls of said inner enclosure.
3. A refrigerator cabinet, a main food space in said refrigerator, 9. door for said main food space, means for cooling said main food space, a second insulated enclosure within said refrigerator, a door for said enclosure, means for cooling said enclosure, the contacting surfaces of the last said door and the stationary portion of said enclosure being formed of substantially solid and noncompresslble material, and means for forcibly breaking an ice bond between the last said door and said enclosure walls.
4. A refrigerator cabinet, an outer metal wall of said cabinet, an inner metal lining of said cabinet, a door opening piercing both said outer wall and lining, thermal insulating "material located in the space between said out r wall and lining, rigid means securing said lining to said wall adjacent the peripheral boundary of said opening; and a one-piece integral frame surrounding said opening at said boundary and encompassing said rigid means and joining said outer wall and lining.
5. The method of molding a frame for a refrigerator door opening comprising the steps of assembling an inner shell to an outer shell with thermal insulating material between said shells, of adding material to form a frame, and of employing portions of said shells extending beyond said insulation as portions oi? the mold for forming said frame.
6. A refrigerator cabinet, a rectangular door for said cabinet hinged upon a vertical axis, inner and outer sheets forming exposed surfaces of said door, tension means holding said sheets together, and a frame for said door comprising an endless piece of molded material having a relatively low thermal conductivity, said tension means being embedded in said molded material.
7. A refrigerator cabinet, a door hinged to said cabinet, and surfaces on said cabinet and on said door adapted to contact each other when the door is closed, said contact surfaces on the hinge side and the opposite side of the door being disposed in different planes, each approximately radial with respect to the hinge axis of said door.
8. A refrigerator cabinet, a door opening in said cabinet. a door adapted to close and at least partly fill said opening, latch means for said door, hinge means for said door, the plane of contacts between said door and the cabinet being at a different angle on the hinge side of the door from those on other sides of the door, said planes joining each other at corners adjacent to the hinge side of the door by means of continuous compound curves.
9. In a refrigerator cabinet, an outer metal shell, an inner metal shell, thermal insulation between said shells, a plurality of compression members braced between the forward edges of said shells to hold the inner shell against the insulation located between the rear walls of said shells, and mass for securing an compression members in place, including a frame member in which said compression members are embedded. 10. A rerrigerator door, an outer metal wall or said door, an inner wall of said door, a thickness of thermal insulation material between said walls, a plurality of tension members Joining the edges of said walls to secure said insulation in place and form a rigid structure, and a one-piece frame formed of a plastic material joining said walls and covering said tension members.
11. A refrigerator cabinet comprising an outer housing member, an inner housing member within and spaced from said outer member, the space between said members providing a chamber, thermal insulating material positioned within chamber, said material being sufliciently rigid to support said inner member, said members having registering openings to provide a means of access to said inner member, said members being provided adjacent the marginal edges of said openings with flange portions extending generally toward each other and partially across said cham- \ber, said flange portions being spaced from said insulating material to provide a space therebetween, supporting members extending between the flange portions of said members whereby said use, said name being imam-any independent 01' said insulating material.
sensations crrEn The following references are of record in the tile 01 this patent:
UNITED STATES PATENTS m Number Name Date Geyer Apr. 8, 1930 Spreen Apr. 8, 1930 Brouse Apr. 7, 1936 Chilton Feb. 2, 1937 Gould Feb. 1, 1938 King Apr. 19, 1938 Darbyshire May 10, 1938 Philipp Apr. 18, 1939 Geyer Feb. 13, 1940 Teeter May 21, 1940 Newill Nov. 19, 1940 Schmieding Apr. 22, 1941 Ullstrand Nov; 4, 1941 Steenstrup Dec. 16, 1941 Lenning Apr. 7, 1942 Peltier Sept. 29, 1942 Dempsey Feb. 23, 1943 Ashbaugh Apr. 18, 1944 McCloy June 13, 1944 Iwashita Nov. 28, 1944 Hedlund May 8, 1945 Muilly Nov. 5, 1946 Johnson Oct. 28, 1947