Refrigeration – Refrigeration producer – Sorbent type
Reexamination Certificate
1999-07-12
2001-03-20
Doerrler, William (Department: 3744)
Refrigeration
Refrigeration producer
Sorbent type
C062S494000, C062S484000
Reexamination Certificate
active
06202436
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to an absorption cooling apparatus that is used as an outdoor machine for an absorption air conditioning system and which cools the heat transfer medium used to activate the cooling operation of an indoor air conditioner. The invention particularly relates to an improvement of the mechanism for cooling the heat transfer medium.
Among the known absorption cooling apparatuses is the one shown in
FIG. 3
that has an evaporating/absorbing section of dual pipe type in which a cylindrical outer pipe
1
and a coaxial evaporating pipe
2
that penetrates both the top and bottom of the outer pipe
1
, with an evaporating/absorbing compartment
3
being formed between the inner peripheral surface of the outer pipe
1
and the outer peripheral surface of the evaporating pipe
2
. This evaporating/absorbing section has refrigerant dispense pipes
4
that penetrate the top plate of the outer pipe
1
to project into the evaporating/absorbing compartment
3
. A liquid refrigerant is dispensed through the pipes
4
onto the outer peripheral surface of the evaporating pipe
2
so that the heat of vaporization resulting from the evaporation of the liquid refrigerant cools a heat transfer medium (which is usually cold water and hereunder referred to as “cold water”) that passes through the evaporating pipe
2
from top to bottom or vice versa. The evaporating/absorbing section also has absorbing liquid dispense pipes
5
that penetrate the top plate of the outer pipe
1
to project into the evaporating/absorbing compartment
3
. The refrigerant vapor formed in the compartment
3
is absorbed by an absorbing liquid that is dispensed through those pipes
5
onto the inner peripheral surface of the outer pipe
1
. The absorbing liquid L that has been diluted upon absorbing the refrigerant vapor collects in the bottom of the outer pipe
1
, from which it is discharged to the outside.
In order to enhance the efficiency with which cold water is cooled in the evaporating/absorbing section, the velocity of the cold water flowing through the evaporating pipe
2
must be increased. The cold water flowing through the evaporating pipe
2
is cooled more efficiently in portions close to the wall surface than in the portion close to the center of the pipe. At low velocity, the cold water forms laminar flows and the stream flowing through the center of the evaporating pipe
2
does not easily mix with the stream flowing along the wall surface, thus contributing to a lowered cooling efficiency. In addition, the evaporating pipe
2
itself is cooled and the refrigerant water dispensed onto the outer peripheral surface of the evaporating pipe
2
does not easily evaporate. Hence, the cold water flowing through the evaporating pipe
2
desirably forms turbulent flows. In order to create turbulent flows, the velocity of the cold water must be increased by inserting a turbulence promoter such as a coil or reducing the diameter of the evaporating pipe
2
. However, the insertion of a turbulence promoter can increase the cost and weight of the equipment. If the diameter of the evaporating pipe is reduced, a great number of such evaporating pipes must be used or their height (length) has to be increased in order to secure the necessary surface area for the evaporation of the refrigerant and this again increases the cost of the equipment.
In the conventional evaporating/absorbing section, the evaporating pipe
2
penetrates both the top and bottom of the outer pipe
1
and cold water flows either from top to bottom or vice versa. The cold water always passes through the bottom of the outer pipe
1
, so without some special structural design, it may be subject to the heat of the hot absorbing liquid L collecting in the bottom of the outer pipe
1
and this will result in an even lower cooling efficiency.
SUMMARY OF THE INVENTION
The present invention has been accomplished under these circumstances and has as an object providing an absorption cooling apparatus capable of cooling cold water (heat transfer medium) in a higher efficiency.
The stated object of the present invention can be attained by the absorption cooling apparatus according to aspect
1
which comprises a vertically erected outer pipe, an evaporating pipe that penetrates the top of the outer pipe and which is coaxially provided in the interior thereof, the bottom of the evaporating pipe being sealed and spaced from the bottom of the outer pipe such that a heat transfer medium flows in or out from the top, an inner pipe that is coaxially provided in the interior of the evaporating pipe and which has the bottom thereof open in a position near the bottom of the evaporating pipe to allow the heat transfer medium from the evaporating pipe to flow in through the opening in the bottom thereof or allows the heat transfer medium to flow out through the same opening and an evaporating/absorbing compartment formed between the outer pipe and the evaporating pipe, wherein the heat transfer medium flowing through the evaporating pipe is cooled by the evaporation of a liquid refrigerant that is dispensed through the outer pipe onto the outer peripheral surface of the evaporating pipe and the resulting refrigerant vapor is absorbed by an absorbing liquid dispensed through the outer pipe onto the inner peripheral surface of the outer pipe.
The channel of the heat transfer medium flowing through the evaporating pipe is narrowed by the inner pipe provided in the interior thereof, causing the heat transfer medium to collect toward the wall surface of the pipe. As a result, the efficiency at which the heat transfer medium is cooled is substantially enhanced. The reduced cross-sectional area of the channel of the heat transfer medium through the evaporating pipe has an added advantage in that if an equal volume of cold water flows in, the relative increase in its velocity leads to a further increase in the efficiency at which the heat transfer medium is cooled. What is more, the bottom of the evaporating pipe is spaced from the bottom of the outer pipe, so unlike in the prior art absorption cooling apparatus, the evaporating pipe is immune to the effects of the hot absorbing liquid collected in the bottom of the outer pipe and the efficiency of cooling the heat transfer medium is further enhanced.
REFERENCES:
patent: 4477396 (1984-10-01), Wilkinson
patent: 4567736 (1986-02-01), Van Der Sluys et al.
patent: 4791790 (1988-12-01), Tongu
patent: 4872319 (1989-10-01), Tongu
patent: 5499516 (1996-03-01), Andersson et al.
patent: 5572884 (1996-11-01), Christensen et al.
patent: 5794456 (1998-08-01), Ishiguro et al.
patent: 5857354 (1999-01-01), Ishiguro
patent: 5875649 (1998-08-01), Ishiguro et al.
patent: 1-134177 (1989-05-01), None
patent: 10-26437 (1998-01-01), None
Ishiguro Katsusuke
Kamiya Hiroshi
Maruyama Akira
Doerrler William
Oliff & Berridge PLC.
Paloma Industries Limited
Shulman Mark
LandOfFree
Absorption cooling apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Absorption cooling apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Absorption cooling apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2501158