US2721451A

US2721451A - Drain pan

Info

Publication number: US2721451A
Application number: US295273A
Authority: US
Inventors: Frank A Schumacher
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1952-06-24
Filing date: 1952-06-24
Publication date: 1955-10-25
Anticipated expiration: 1972-10-25

Description

Got. 25, 1955 F. A. SCHUMACHER 2,721,451

DRAIN PAN Filed June 24, 1952 Irwverwtm Fr-emK ASchumacher His Attorneg.

United States Patent DRAIN PAN Frank A. Schumacher, Erie, Pa., assignor to General Electric Company, a corporation of New York Application June 24, 1952, Serial N 0. 295,273

1 Claim. (Cl. 62-103) My invention relates to refrigerators and pertains more particularly to refrigerator defrosting apparatus.

Some refrigerators include means for automatically defrosting those surfaces in the food storage compartment thereof upon which frost forms and collects. Often such refrigerators also include means whereby moisture resulting from a defrosting operation is evaporated into the atmosphere outside the food storage compartments and thereby disposed of. One arrangement for so disposing of the defrost moisture includes an auxiliary condenser located in the machinery compartment of the refrigerator and a rigid drain pan in heat exchange relationship with the auxiliary condenser. The defrost moisture is directed into the drain pan from the defrosted surfaces and is evaporated by heat from the auxiliary condenser. The evaporation of defrost moisture from the drain pan is determined by the amount of heat transfer from the auxiliary condenser to the drain pan. It has been recognized that by increasing the heat transfer a smaller drain pan may be employed in the arrangement. Employment of a smaller drain pan is desirable from the standpoints of economy in manufacture and conservation of space in the machinery compartment. Heretofore the thermal conductivity has been increased by bonding a pan to the auxiliary condenser. In such an arrangement, however, it proved difiicult to clean the pan, which invited neglect, resulting in pan corrosion and the presence of malodorous residues. Then a plate was secured to the condenser for removably supporting the rigid pan and increasing the heat conductivity to the pan. Due to manufacturing difliculties in providing a flat bottom pan and a flat plate, only three point contact resulted between the pan bottom and the plate and insulative air gaps existed between the pan and the plate.

The primary object of my invention is to provide in a refrigerator including defrosting means an improved arrangement for evaporating and thereby disposing of moisture resulting from a defrosting operation.

Another object of my invention is to provide in a refrigerator including defrosting means and an auxiliary condenser, an improved defrost moisture drain pan whereby high thermal conductivity between the auxiliary condenser and the drain pan and a resultant high defrost moisture evaporation rate are insured.

Further objects and advantages of my invention will become apparent as the following description proceeds and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming part of this specification.

In carrying out the objects of my invention, I provide a defrost moisture receptacle having a flexible bottom and adapted to be supported by a heated member. The flexible bottom conforms to the heated member and thereby increases the thermal conductivity therebetween.

For a better understanding of my invention, reference may be had to the accompanying drawing in which Fig. 1 is a fragmentary view of a refrigerator partly broken away to illustrate the preferred embodiment of my in- Patented Oct. 25, 1955 vention; Fig. 2 is an enlarged fragmentary sectional view of the preferred embodiment of my invention; Fig. 3 is an enlarged fragmentary sectional view illustrating an alternative manner of supporting the defrost moisture receptacle; and Fig. 4 is an enlarged fragmentary sectional view illustrating a second embodiment of my invention.

In Fig. 1 is partially illustrated a refrigerator cabinet 1 including a food storage compartment shown in outline and indicated by 2, and a machinery compartment 3 disposed below the food storage compartment. A door 4 hingedly mounted on the refrigerator cabinet 1 is provided for closing an access opening to the food storage compartment 2.

Located in the machinery compartment 3 is a refrigerating unit 5. The refrigerating unit 5 is included in a refrigeration system provided for cooling the fresh food compartment. Also included in the refrigerating system and located in the machinery compartment 3 is an auxiliary condenser 6 which in operation assists the main condenser in the system (not shown) in dissipating heat absorbed by the system from the food storage compartment. During normal operation of the refrigerating system the absorption of heat from the food storage compartment 2 results in the formation of frost therein. By means not shown the refrigerator is periodically de- .frosted. The water or moisture resulting from the defrosting operation is collected by suitable means and is conducted by a tube 7 to the machinery compartment 3.

As seen in Figs. 1 and 2 the above-mentioned auxiliary condenser 6 may comprise a single conduit arranged in serpentine form and including a plurality of passes 8 disposed in a common horizontal plane. Secure to the upper sides of the passes 8, as by welding, is a member or condenser plate 9, formed of steel or any similar heat conductive material. In this arrangement, the plate 9 is heated by the warm refrigerant flowing through the passes 8 of the auxiliary condenser 6. It is to be understood that means other than the auxiliary condenser may be employed to heat the member or plate 9. Supported by the'condenser plate 9 in a position to receive the defrost moisture from the tube 7 is my improved drain pan or receptacle 10. The embodiment of my invention illustrated in Figs. 1 and 2 is constructed wholly of a flexible heat conductive material, for example, a plastic material such as polystyrene. It is to be understood of course that other materials can also be used depending on flexibility, cost, durability, etc. The thickness of the material of which the drain pan is formed and the configuration of the drain pan are such that the drain pan is structurally strong enough to hold water and not collapse when picked up. Yet the pan material is flexible enough so that the bottom indicated by 11 in Fig. 2 conforms to the top side of the condenser plate 9 when resting thereon. This insures a high rate of thermal conductivity from the condenser plate 9 to the drain pan 10 and results, therefore, in a high rate of evaporation of the defrost moisture, indicated by 12 in Figs. 1 and 2, from the drain pan.

As the drain pan 10 becomes progressively more filled, the weight of the moisture 12 to be evaporated increases the conformance of the pan bottom 11 to the plate 9 and increases the force with which the pan bottom engages the plate. Thus, the thermal conductivity and moisture evaporation rates increase with the rising of the level of the defrost moisture 12 toward the point of overflow whereby the danger of overflowing is minimized. Similarly, if there should be any low spots where there is a greater tendency for water to collect, this greater amount of water also increases the contact and heat conduction between the pan and the plate 9, thereby providing increased evaporation where it is most needed.

As seen in Fig. 3, the drain pan 10 may be supported by the passes 8 of the condenser 6 instead of by the plate 9 secured to the passes. In such an arrangement, the flexible bottom '11 conforms to and engages a substantial surface area of each of the passes Sfin the manner shown in solid lines in Fig. 3. As the drain pan, becomes progressively more filled, the Weight of the moisture 12 to be evaporated causes the portions of the bottom 11 of the pan between the passes 8 to move downwardly toward the position shown in dash lines in Fig. 3. This increases the total area of engagement between the pan bottom 11 and the condenser passes 8, whereby the thermal conductivity and moisture evaporation rates are increased. It will be seen that as the drain pan becomes progressively more filled and closerto the point of overflow, the surface engagement between the bottom of the pan and the condenser passes increases. Thus, the thermal conductivity and moisture evaporation rates I increase in proportion to increase in the amount of defrost moisture contained in the pan whereby the danger of overflowing is minimized.

In Fig. 4 is illustrated a modified form of my drain pan designated 13. The modified drain pan 13 comprises a rigid frame 14 formed of steel or the like and a flexible bottom 15 which may be formed of the'same material as the first described embodiment lit. The bottom side of the frame 14 is formed to include an inwardly extending flange 16 to which is suitably secured in a leakproof manner the edges of the flexible bottom 15.

It will be seen that in this form of my invention the frame 14 may be relied upon for providing the necessary pan rigidity. Therefore, the bottom 15 may be thinner; and a more flexible material may be employed for the bottom since the flexibility of the material selected will not be at determining factor in the rigidity of the pan and the capability of the pan to hold Water and not collapse if lifted. With a thinner and more flexible bottom, maximum conformance of the pan bottom to the condenser plate 9 and a shorter heat path to the defrost moisture 12 will be afforded. This will result in a more substan- I tial surface engagement between the pan bottom 15 and the condenser plate 9 whereby higher thermal conductivity and defrost moisture evaporation rates will be obtained.

It is to be understood that in this form of the invention, too, the conformance of the pan bottom 15 to the plate 9 and the force Withwhich the pan bottom engages the plate increases as the amount of moisture contained by the drain pan increases for thereby minimizing the danger of overflowing. It .is to be understood further that my'mo'dified drain pan 13 may also be supported by the passes 8 of the condenser 6 insteadof by the plate 9 secured to the passes in the same manner and for the same purposes described above with respect to the first embodiment 10, and as illustrated in Fig. 3.

While specific embodiments of my invention have been shown and described, it is not desired that my invention be limited to the particular form shown and described and it is inte'nded by the appended-claims to cover all modifications'within the spirit and scope of my invention.

What I claim as new and desire to be secured by Letters Patent of the United States is:

In a refrigerator, defrost moisture disposing means comprising; a serpentine condenser including a plurality of passes and a defrost moisture evaporating receptacle removably supported by said condenser passes, said receptacle including substantially, rigid sides and a flexible bottom, said flexible bottom engaging and conforming to said condenser passes whereby high thermal conductivity and defrost moisture evaporation rates are insured, the total surface engagement of said flexible bottom with said condenser passes being proportionate to the amount of moisture contained in said receptacle.

Alsing July 25, 1939 Schlumbohn Sept. 26, 1939