Evaporator with improved condensate collection

Details Evaporator with improved condensate collection Evaporator with improved condensate collection

1991-04-02

2001-02-06

Tapolcai, William E. (Department: 3744)

Refrigeration

With means preventing or handling atmospheric condensate...

Retainer or flow director for atmospheric condensate

C062S525000, C165S176000

Reissue Patent

active

RE037040

ABSTRACT:

FIELD OF THE INVENTION
This invention relates to heat exchangers, particularly heat exchangers employed as evaporators; and to the collection of condensate in evaporators.
BACKGROUND OF THE INVENTION
As is well known, commonly employed air conditioning systems operating on a vapor compression cycle utilize evaporators as a means of cooling tee air to be conditioned. A refrigerant is flowed through an evaporator and expanded therein. In so doing, it absorbs its heat of vaporization, thereby cooling the medium with which it is in contact, typically heat exchanger tubes. The air to be conditioned is flowed over those tubes (which typically will be provided with fins for improved heat transfer). The air, at least locally, will be cooled below its dew point with the result that water will condense out of the air on the fins and on the tubes. This condensate must be removed or else it will freeze and plug the air flow path.
A variety of proposals for condensate removal have evolved and in their simplest form, involve the use of gravitation forces with a possible assist from the velocity of the air stream moving through the evaporator. These systems work rather well but frequently are bulky.
Furthermore, where relatively high velocity air streams may be present as, for example, in vehicular air conditioning systems where fans operate at high speed to achieve maximum cooling in a short period of time, it is desirable to remove the moisture from the evaporator as quickly as possible to prevent it from being entrained in the air steam and entering the passenger compartment of the vehicle. Furthermore, it is desirable, in order to obtain fuel economy, that the means employed to collect condensate weigh as little as possible. It is also desirable that the bulk of the same be absolutely minimized.
Furthermore, and equally importantly, it is desirable to provide a means whereby condensate is conducted away from the heat exchange surfaces of the heat exchanger so as to prevent condensate films from interfering with efficient heat transfer.
The present invention is directed to obtaining the above objects.
SUMMARY OF THE INVENTION
It is the principal object of the invention to provide a new and improved heat exchanger. More specifically, it is an object of the invention to provide a new and improved heat exchanger which is ideally suited for use as an evaporator and which includes improved means for collecting condensate that may condense on heat exchange surfaces during operation of the heat exchanger as an evaporator.
According to one facet of the invention, the foregoing object is achieved in a structure including a plurality of substantially identical rows of flattened tubes. Each of the rows is slightly spaced from adjacent other ones of the rows. Corresponding tubes in each row are aligned with corresponding tube in the other rows. The evaporator also includes the plurality of rows of serpentine fins extending generally transversely of the rows of flattened tubes and between corresponding tube pairs in each of the tube rows to be in heat exchange relation with the flattened tubes. Headers are provided to be in fluid communication with the flattened tubes.
According to this facet of the invention, there results, because of the slight spacing between the rows of tubes, spaces between the corresponding tubes in adjacent rows as well as the serpentine fins. With the tubes arranged non horizontally, the condensate may flow along the length of the tubes through these spaces under the influence of gravity to be collected.
According to another facet of the invention, there is provided an evaporator including a lower header comprised of a plurality of elongated, side by side, abutting header tubes of non rectangular cross section. Means defining a plurality of fluid passages for fluid to be evaporated are in fluid communication with the header tubes. Means are provided to seal the interfaces of the header tubes along the length thereof thereby defining upwardly opening condensate receiving channels because of the non rectangular cross sections of the header tubes. Finally, means are provided for holding the header tubes in assembled relation.
As a result of the foregoing, the header tubes not only serve the usual functions of headers, but their exterior surfaces serve as condensate collecting channels as well. This facet of the invention does away with the need for a separate condensate collector.
In a highly preferred embodiment of the invention both of the foregoing features are incorporated in a single structure. Thus such a preferred embodiment of the invention contemplates a plurality of heat exchange modules each comprised of an elongated lower header of non rectangular cross section and a plurality of tubes mounted by the header along its length and extending therefrom in side by side relation. The tubes, in the direction transversely of the header, have a lesser dimension than the header and the modules are stacked and assembled together with the lower headers in sealing abutment with each other and defining the upwardly open channels as mentioned previously. Sets of serpentine fins extend between adjacent tubes in each module.
In one embodiment of the invention, sets of serpentine fins are unique to each module while in another embodiment of the invention, not only do the serpentine fins extend between the adjacent tubes in each module, they additionally extend between the plurality of modules as well.
In a highly preferred embodiment, the headers are defined by header tubes and the sealing abutment is defined by a bond between adjacent headers along the length thereof. The bond also serves as the holding means whereby the headers are held together. In a highly preferred embodiment, the bond is formed by braze metal.
Because of their ready availability, the tubes utilized in forming the headers preferably are of generally circular cross section. A circular cross section is preferred because of its greater resistance to internal pressure.
As an alternative to the us of tubes bonded together to form the headers, the invention contemplates that a unitary structure having essentially the same cross section may be formed by means of extrusion and used as the headers.
According to one embodiment of the invention, the flattened tubes are each individually formed while still another embodiment of the invention contemplates that groups of flattened tubes may be in the form of a multiple passage extrusion.
Other objects and advantages will become apparent from the following specification taken in connection with the accompanying drawings.


REFERENCES:
patent: 1899080 (1933-02-01), Dalghesh
patent: 2093256 (1937-09-01), Stiel
patent: 2874555 (1959-02-01), Disinger et al.
patent: 3030782 (1962-04-01), Karmazin
patent: 3161234 (1964-12-01), Rannenberg
patent: 3976128 (1976-08-01), Patel et al.
patent: 4217953 (1980-08-01), Sonoda et al.
patent: 4274482 (1981-06-01), Sonoda
patent: 4353224 (1982-10-01), Nogogaki et al.
patent: 4371034 (1983-02-01), Yamada et al.
patent: 4379486 (1983-04-01), Kurihara
patent: 4434843 (1984-03-01), Alford
patent: 4448241 (1984-05-01), Andres et al.
patent: 4470455 (1984-09-01), Sacca
patent: 4487038 (1984-12-01), Iijima
patent: 4503907 (1985-03-01), Tanaka et al.
patent: 4513577 (1985-04-01), Wilson et al.
patent: 4557324 (1985-12-01), Kondo et al.
patent: 4566290 (1986-01-01), Otterbein
patent: 4570700 (1986-02-01), Ohara et al.
patent: 4580624 (1986-04-01), Ishida et al.
patent: 4585055 (1986-04-01), Nakayama et al.
patent: 4586346 (1986-05-01), St Pierre
patent: 4586566 (1986-05-01), Kern et al.
patent: 4588025 (1986-05-01), Imai et al.
patent: 4592414 (1986-06-01), Beasley
patent: 4600053 (1986-07-01), Patel et al.
patent: 4614231 (1986-09-01), Proctor et al.
patent: 4615383 (1986-10-01), Hisao
patent: 4615384 (1986-10-01), Shimada et al.
patent: 4620590 (1986-11-01), Koisuka et al.
patent: 4621685 (1986-11-01), Nozewa
patent: 4621687 (1986-11-01), Ikuta et al.
patent: 4693307 (1987-09-01), Scarselletta
patent: 198993 (1982-12-01), None
patent: 217196 (1983-12-01)

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