U.S. patent application number 10/543155 was filed with the patent office on 2006-11-30 for heat transfer fin, heat exchanger, evaporator and condenser for use in car air-conditioner.
Invention is credited to Shinobu Yamauchi.
Application Number | 20060266503 10/543155 |
Document ID | / |
Family ID | 33111948 |
Filed Date | 2006-11-30 |
United States Patent
Application |
20060266503 |
Kind Code |
A1 |
Yamauchi; Shinobu |
November 30, 2006 |
Heat transfer fin, heat exchanger, evaporator and condenser for use
in car air-conditioner
Abstract
A heat transfer fin is capable of enhancing heat transfer rate,
decreasing pressure loss, and is excellent in heat exchanging
performance. A corrugated fin (53) as the heat tranfer fin is
disposed between adjacent heat exchanging tubes (51 and 52). The
corrugated fin (53) is formed by connecting a plurality of louver
fins (54) in a zigzag manner, and is provided with a plurality of
louvers (55) formed at certain intervals. Thus, an air passage (56)
is formed between the louver fins (54). The windward side edge
(54a) of the louver fin (54) and the windward side edge (55a) of
the louver (55) are respectively formed into a semielliptic
cross-sectional configuration which becomes thinner toward the
windward side.
Inventors: |
Yamauchi; Shinobu; (Tochigi,
JP) |
Correspondence
Address: |
C. IRVIN MCCLELLAND;OBLON, SPIVAK, MCCLELLAND, MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Family ID: |
33111948 |
Appl. No.: |
10/543155 |
Filed: |
January 23, 2004 |
PCT Filed: |
January 23, 2004 |
PCT NO: |
PCT/JP04/00623 |
371 Date: |
May 22, 2006 |
Current U.S.
Class: |
165/152 |
Current CPC
Class: |
F28F 1/128 20130101 |
Class at
Publication: |
165/152 |
International
Class: |
F28D 1/02 20060101
F28D001/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 23, 2003 |
JP |
2003-15045 |
Mar 14, 2003 |
US |
60454525 |
Claims
1. A heat transfer fin, comprising: a heat transfer plate for
transferring heat of a heat transfer medium via the heat transfer
plate, the heat transfer plate being disposed parallel or nearly
parallel to a flowing direction of the heat transfer medium,
wherein a heat transfer medium inlet side edge of the heat transfer
plate is formed so as to become thinner toward an upstream side of
a heat transfer medium flowing direction.
2. The heat transfer fin as recited in claim 1, wherein a heat
transfer medium outlet side edge of the heat transfer plate is
formed so as to become thinner toward a downstream side of the heat
transfer medium flowing direction.
3. A heat transfer fin, comprising: a plurality of heat transfer
plates disposed in parallel with each other at certain intervals to
form an air passage between adjacent heat transfer plates, whereby
heat of air passing through the air passage is transferred via the
heat transfer plates, wherein a windward side edge of the heat
transfer plate is formed so as to become thinner toward a windward
side of the air.
4. The heat transfer fin as recited in claim 3, wherein the
plurality of heat transfer fins are disposed independently as plate
fins.
5. The heat transfer fin as recited in claim 3, wherein the
plurality of heat transfer fins are connected such that adjacent
heat transfer fins are connected to form a corrugated fin.
6. A heat transfer fin, comprising: a plurality of heat transfer
plates disposed between a pair of heat exchanging tubes arranged in
parallel at a certain distance, the plurality of heat exchanging
plates being disposed in parallel with each other at certain
intervals along a longitudinal direction of the heat exchanging
tube to form an air passage between adjacent heat exchanging tubes,
whereby air passing through the air passage exchanges heat with
refrigerant passing through the heat exchanging tubes, wherein a
windward side edge of the heat transfer plate is formed so as to
become thinner toward a windward side of the air.
7. The heat transfer fin as recited in claim 6, wherein the
plurality of heat transfer plates are disposed independently as
plate fins.
8. The heat transfer fin as recited in claim 6, wherein the
plurality of heat transfer plates are connected such that adjacent
heat transfer fins are connected to form a corrugated fin.
9. The heat transfer fin as recited in claim 6, wherein the
plurality of heat transfer plates are integral skived fins formed
by skiving a surface of the heat exchanging tube.
10. The heat transfer fin as recited in any one of claims 3 to 9,
wherein a cross-sectional contour configuration of the windward
side edge of the heat transfer plate is formed into a curved
configuration.
11. The heat transfer fin as recited in claim 10, wherein a
cross-sectional contour configuration of the windward side edge of
the heat transfer plate is formed into a semielliptic
configuration.
12. The heat transfer fin as recited in claim 10, wherein a
cross-sectional contour configuration of the windward side edge of
the heat transfer plate is formed into a semicircular
configuration.
13. The heat transfer fin as recited in any one of claims 3 to 9,
wherein a cross-sectional contour configuration of the windward
side edge of the heat transfer plate is formed into a polygonal
configuration.
14. The heat transfer fin as recited in claim 13, wherein the
cross-sectional contour configuration of the windward side edge of
the heat transfer plate is formed into a triangular configuration
with an acute-angled tip.
15. The heat transfer fin as recited in any one of claims 3 to 14,
wherein a leeward side edge of the heat transfer plate is formed so
as to become thinner toward a leeward side of the air.
16. A heat transfer fin, comprising: a heat transfer plate disposed
parallel or nearly parallel to a heat transfer medium passing
direction, the heat transfer plate being provided with a plurality
of louvers at certain intervals along the heat transfer medium
passing direction to transfer heat of the heat transfer medium via
the heat transfer plate, wherein a heat transfer medium inlet side
edge of the louver is formed so as to become thinner toward an
upstream side of the heat transfer medium passing direction.
17. The heat transfer fin as recited in claim 16, wherein a heat
transfer medium outlet side edge of the heat transfer plate is
formed so as to become thinner toward a downstream side of the heat
transfer medium passing direction.
18. A heat transfer fin, comprising: a plurality of heat transfer
plates disposed in parallel with each other at certain intervals to
form an air passage between adjacent heat transfer plates, the heat
transfer plate being provided with a plurality of louvers at
certain intervals along the air passage to transfer heat of air
passing through the air passage via the heat transfer plate,
wherein a windward side edge of the louver is formed so as to
become thinner toward an upstream side of the air.
19. The heat transfer fin as recited in claim 18, wherein the
plurality of heat transfer fins are connected such that adjacent
heat transfer fins are connected to form a corrugated fin.
20. A heat transfer fin, comprising: a plurality of heat transfer
plates disposed between a pair of heat exchanging tubes arranged in
parallel at a certain distance, the plurality of heat transfer
plates being disposed in parallel with each other at certain
intervals along a longitudinal direction of the heat exchanging
tube to form an air passage between adjacent heat transfer plates,
and the heat transfer plate being provided with a plurality of
louvers at certain intervals along the air passage, whereby air
passing through the air passage exchanges heat with refrigerant
passing through the heat exchanging tubes, wherein a windward side
edge of the louver is formed so as to become thinner toward a
windward side of the air.
21. The heat transfer fin as recited in claim 20, wherein the
plurality of heat transfer fins are connected such that adjacent
heat transfer fins are connected to form a corrugated fin.
22. The heat transfer fin as recited in any one of claims 18 to 21,
wherein a cross-sectional contour configuration of the windward
side edge of the louver is formed into a curved configuration.
23. The heat transfer fin as recited in claim 22, wherein a
cross-sectional contour configuration of the windward side edge of
the louver is formed into a semielliptic configuration.
24. The heat transfer fin as recited in claim 22, wherein a
cross-sectional contour configuration of the windward side edge of
the louver is formed into a semicircular configuration.
25. The heat transfer fin as recited in any one of claims 18 to 21,
wherein a cross-sectional contour configuration of the windward
side edge of the louver is formed into a polygonal
configuration.
26. The heat transfer fin as recited in claim 25, wherein the
cross-sectional contour configuration of the windward side edge of
the louver is formed into a triangular configuration with an
acute-angled tip.
27. The heat transfer fin as recited in any one of claims 18 to 26,
wherein a leeward side edge of the louver is formed so as to become
thinner toward a leeward side of the air.
28. A heat transfer fin, comprising: a heat transfer plate disposed
parallel or nearly parallel to a heat transfer medium passing
direction, the heat transfer plate being provided with a plurality
of louvers at certain intervals along the heat transfer medium
passing direction to transfer heat of the heat transfer medium via
the heat transfer plate, wherein a heat transfer medium inlet side
edge of the heat transfer plate and that of the louver are
respectively formed so as to become thinner toward an upstream side
of the heat transfer medium passing direction.
29. The heat transfer fin as recited in claim 28, wherein at least
one of heat transfer medium outlet side edges of the heat transfer
plate and the louver is formed so as to become thinner toward a
downstream side of the heat transfer medium passing direction.
30. A heat transfer fin, comprising: a plurality of heat transfer
plates disposed in parallel with each other at certain intervals to
form an air passage between adjacent heat transfer plates, the heat
transfer plate being provided with a plurality of louvers at
certain intervals along the air passage to transfer heat of air
passing through the air passage via the heat transfer plate,
wherein a windward side edge of the heat transfer plate and that of
the louver are respectively formed so as to become thinner toward
an upstream side of the air.
31. The heat transfer fin as recited in claim 30, wherein at least
one of leeward side edges of the heat transfer plate and the louver
is formed so as to become thinner toward a leeward side of the
air.
32. A heat transfer fin, comprising: a plurality of heat transfer
plates disposed between a pair of heat exchanging tubes arranged in
parallel at a certain distance, the plurality of heat exchanging
plates being disposed in parallel with each other at certain
intervals along a longitudinal direction of the heat exchanging
tube to thereby form an air passage between adjacent heat transfer
plates, the heat transfer plate being provided with a plurality of
louvers at certain intervals along the air passage, whereby air
passing through the air passage exchanges heat with refrigerant
passing through the heat exchanging tubes, wherein a windward side
edge of the heat transfer plate and that of the louver are
respectively formed so as to become thinner toward a windward side
of the air.
33. The heat transfer fin as recited in claim 32, wherein at least
one of leeward side edges of the heat transfer plate and the louver
is formed so as to become thinner toward a leeward side of the
air.
34. A heat transfer fin disposed in a heat exchanging tube through
which refrigerant passes, the heat transfer fin comprising a heat
transfer plate arranged parallel to a refrigerant passing direction
to transfer heat of the refrigerant via the heat transfer plates,
wherein a refrigerant inlet side edge of the heat transfer plate is
formed so as to become thinner toward an upstream side of the
refrigerant passing direction.
35. The heat transfer fin as recited in claim 34, wherein a
refrigerant outlet side edge of the heat transfer plate is formed
so as to become thinner toward a downstream side of the refrigerant
passing direction.
36. A heat transfer fin disposed in a heat exchanging tube through
which refrigerant passes, the heat transfer fin comprising a
plurality of heat transfer plates arranged parallel to a
refrigerant passing direction, the heat transfer plates being
provided with openings in a zigzag form to transfer heat of the
refrigerant via the heat transfer plates, wherein a side edge of
the opening of the heat transfer plate facing an upstream side of
the refrigerant passing direction is formed so as to become thinner
toward the upstream side of the refrigerant passing direction.
37. The heat transfer fin as recited in claim 36, wherein a side
edge of the opening of the heat transfer plate facing a downstream
side of the refrigerant passing direction is formed so as to become
thinner toward the downstream side of the refrigerant passing
direction.
38. A heat transfer fin disposed in a heat exchanging tube through
which refrigerant passes, the heat transfer fin comprising a
plurality of heat transfer plates arranged parallel to a
refrigerant passing direction, the heat transfer plates being
provided with openings in a zigzag form to transfer heat of the
refrigerant via the heat transfer plates, wherein a refrigerant
inlet side edge of the heat transfer plate is formed so as to
become thinner toward an upstream side of the refrigerant passing
direction, and wherein a side edge of the opening of the heat
transfer plate facing the upstream side of the refrigerant passing
direction is formed so as to become thinner toward the upstream
side of the refrigerant passing direction.
39. The heat transfer fin as recited in claim 38, wherein a
refrigerant outlet side edge of the heat transfer plate is formed
so as to become thinner toward a downstream side of the refrigerant
passing direction.
40. The heat transfer fin as recited in claim 38 or 39, wherein a
side edge of the opening of the heat transfer plate facing a
downstream side of the refrigerant passing direction is formed so
as to become thinner toward the downstream side of the refrigerant
passing direction.
41. A heat exchanger equipped with a heat transfer fin as recited
in any one of claims 1 to 40.
42. An evaporator for use in car air-conditioners, the evaporator
being equipped with a heat transfer fin as recited in any one of
claims 1 to 40.
43. A condenser for use in car air-conditioners, the condenser
being equipped with a heat transfer fin as recited in any one of
claims 1 to 40.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is an application filed under 35 U.S.C.
.sctn.111(a) claiming the benefit pursuant to 35 U.S.C. .sctn.
119(e)(1) of the filing date of U.S. Provisional Application No.
60/454,525, filed on Mar. 14, 2003 pursuant to 35 U.S.C. .sctn.
111(b).
[0002] Priority is claimed to Japanese Patent Application No.
2003-15045, filed on Jan. 23, 2003, and U.S. Provisional
Application No. 60/454,525, filed on Mar. 14, 2003, the disclosure
of which are incorporated by reference in their entireties.
TECHNICAL FIELD
[0003] The present invention relates to a heat transfer fin for
heat exchangers such as evaporators or condensers for use in car
air-conditioners, and also relates to a heat exchanger, an
evaporator for use in car air-conditioners or a condenser for use
in car air-conditioners using such heat transfer fins.
BACKGROUND ART
[0004] The following description sets forth the inventor's
knowledge of related art and problems therein and should not be
construed as an admission of knowledge in the prior art.
[0005] It is well known that an evaporator and the like for use in
car air-conditioners includes a plurality of heat exchanging tubes
disposed in parallel with each other and a plurality of thin-plate
like fins as heat transfer plates disposed between the adjacent
heat exchanging tubes and arranged in parallel at certain intervals
along the tube longitudinal direction.
[0006] In such an evaporator, an air passage is formed between
adjacent fins, and heat exchanging is performed between the air
passing through the air passage and the refrigerant passing through
the heat exchanging tubes via the fins.
[0007] In the evaporator, it is considered that increasing the fin
pitch is one of the effective ways for improving the thermal
performance.
[0008] However, as shown in FIG. 14, in a conventional fin 100,
since the cross-sectional contour of the windward side end thereof
is formed into a rectangular shape, the windward side end face 101
is constituted as a nearly vertical surface against the air A
passing through the air passage 110. As a result, when the air A
collides with the windward side end face 101, turbulence of the air
A occurs. Accordingly, increasing the fin pitch causes increased
turbulence of the air A, resulting in an increased pressure loss.
This increased pressure loss deteriorates the inhale amount of the
air A and the inhale velocity of the air A, which in turn may
result in deteriorated heat exchanging performance.
[0009] In other words, when two heat transfer fins each having the
same heat transfer rate are compared, the heat exchanger having a
larger pressure loss is lower in performance, and the heat
exchanger having a smaller pressure loss is higher in performance
and therefore excellent in heat exchanging performance.
[0010] Under the circumstances, for example, Japanese Unexamined
Laid-open Patent Publication No. 60-82786 discloses a fin-and-tube
type heat exchanger in which the leeward side edge of the heat
transfer fin is formed to be thin to decrease the pressure loss
(see FIGS. 2 and 3).
[0011] According to the heat transfer fin shown in the
aforementioned document, the pressure loss can be decreased to some
extent.
[0012] However, in the recent heat exchanger technical field, a
further improvement of heat exchanging performance is required, and
therefore a still further decreased pressure loss and improved heat
transfer rate are desired.
[0013] The description herein of advantages and disadvantages of
various features, embodiments, methods, and apparatus disclosed in
other publications is in no way intended to limit the present
invention. Indeed, certain features of the invention may be capable
of overcoming certain disadvantages, while still retaining some or
all of the features, embodiments, methods, and apparatus disclosed
therein.
[0014] It is an object of the present invention to provide a heat
transfer fin capable of improving heat transfer rate while
decreasing pressure loss to thereby obtain excellent heat
exchanging performance.
[0015] It is another object of the present invention to provide a
heat exchanger using the aforementioned heat transfer fins.
[0016] It is still another object of the present to provide an
evaporator for use in car air-conditioners using the aforementioned
heat transfer fins.
[0017] It is still yet another object of the present invention to
provide a condenser for use in car air-conditioners using the
aforementioned heat transfer fins.
[0018] Other objects and advantages of the present invention will
be apparent from the following preferred embodiments.
DISCLOSURE OF INVENTION
[0019] The first aspect of the present invention employs the
following structure (1).
[0020] (1) A heat transfer fin, comprising:
[0021] a heat transfer plate for transferring heat of a heat
transfer medium via the heat transfer plate, the heat transfer
plate being disposed parallel or nearly parallel to a flowing
direction of the heat transfer medium,
[0022] wherein a heat transfer medium inlet side edge of the heat
transfer plate is formed so as to become thinner toward an upstream
side of a heat transfer medium flowing direction.
[0023] In the heat transfer plate according to the first aspect of
the present invention, since the heat transfer medium inlet side
edge of the heat transfer plate is formed so as to become thinner
toward an upstream side of a heat transfer medium flowing
direction, the heat transfer medium flows smoothly along the
external surface of the heat transfer plate without causing
turbulence. Thus, the flow resistance of the heat transfer medium
decreases, causing a decreased pressure loss, which in turn results
in an enhanced heat transfer rate. As a result, excellent heat
exchanging performance can be obtained.
[0024] In the first aspect of the present invention, it is
preferable to employ the following structure (2).
[0025] (2) The heat transfer fin as recited in the aforementioned
Item (1), wherein a heat transfer medium outlet side edge of the
heat transfer plate is formed so as to become thinner toward a
downstream side of the heat transfer medium flowing direction.
[0026] In this heat transfer fin, the pressure loss can be further
decreased, resulting in a further enhanced heat transfer rate.
[0027] The second aspect of the present invention employs the
following structure (3).
[0028] (3) A heat transfer fin, comprising:
[0029] a plurality of heat transfer plates disposed in parallel
with each other at certain intervals to form an air passage between
adjacent heat transfer plates, whereby heat of air passing through
the air passage is transferred via the heat transfer plates,
[0030] wherein a windward side edge of the heat transfer plate is
formed so as to become thinner toward a windward side of the
air.
[0031] In this heat transfer fin according to the second aspect of
the present invention, in the same manner as mentioned above,
decreasing the pressure loss and enhancing the heat transfer rate
can be attained.
[0032] In the second aspect of the present invention, it is
preferable to employ the following structures (4) and (5).
[0033] (4) The heat transfer fin as recited in the aforementioned
Item (3), wherein the plurality of heat transfer fins are disposed
independently as plate fins.
[0034] (5) The heat transfer fin as recited in the aforementioned
Item (3), wherein the plurality of heat transfer fins are connected
such that adjacent heat transfer fins are connected to form a
corrugated fin.
[0035] The third aspect of the present invention employs the
following structure (6).
[0036] (6) A heat transfer fin, comprising:
[0037] a plurality of heat transfer plates disposed between a pair
of heat exchanging tubes arranged in parallel at a certain
distance, the plurality of heat exchanging plates being disposed in
parallel with each other at certain intervals along a longitudinal
direction of the heat exchanging tube to form an air passage
between adjacent heat transfer plates, whereby air passing through
the air passage exchanges heat with refrigerant passing through the
heat exchanging tubes,
[0038] wherein a windward side edge of the heat transfer plate is
formed so as to become thinner toward a windward side thereof.
[0039] In this heat transfer fin according to the third aspect of
the present invention, in the same manner as mentioned above,
decreasing the pressure loss and enhancing the heat transfer rate
can be attained.
[0040] In the third aspect of the present invention, it is
preferable to employ the following structures (7) to (9).
[0041] (7) The heat transfer fin as recited in the aforementioned
Item (6), wherein the plurality of heat transfer plates are
disposed independently as plate fins.
[0042] (8) The heat transfer fin as recited in the aforementioned
Item (6), wherein the plurality of heat transfer plates are
connected such that adjacent heat transfer fins are connected to
form a corrugated fin.
[0043] (9) The heat transfer fin as recited in the aforementioned
Item (6), wherein the plurality of heat transfer plates are
integral skived fins formed by skiving a surface of the heat
exchanging tube.
[0044] In the second and third aspects of the present invention, it
is preferable to employ the following structures (10) to (15).
[0045] (10) The heat transfer fin as recited in any one of the
aforementioned Items (3) to (9), wherein a cross-sectional contour
configuration of the windward side edge of the heat transfer plate
is formed into a curved configuration.
[0046] (11) The heat transfer fin as recited in any one of the
aforementioned Item (10), wherein a cross-sectional contour
configuration of the windward side edge of the heat transfer plate
is formed into a semielliptic configuration.
[0047] (12) The heat transfer fin as recited in any one of the
aforementioned Item (10), wherein a cross-sectional contour
configuration of the windward side edge of the heat transfer plate
is formed into a semicircular configuration.
[0048] (13) The heat transfer fin as recited in any one of the
aforementioned Items (3) to (9), wherein a cross-sectional contour
configuration of the windward side edge of the heat transfer plate
is formed into a polygonal configuration.
[0049] (14) The heat transfer fin as recited in the aforementioned
Item (13), wherein the cross-sectional contour configuration of the
windward side edge of the heat transfer plate is formed into a
triangular configuration with an acute-angled tip.
[0050] (15) The heat transfer fin as recited in any one of the
aforementioned Item (3) to (14), wherein a leeward side edge of the
heat transfer plate is formed so as to become thinner toward a
leeward side of the air.
[0051] The fourth aspect of the present invention employs the
following structure (16).
[0052] (16) A heat transfer fin, comprising:
[0053] a heat transfer plate disposed parallel or nearly parallel
to a heat transfer medium passing direction, the heat transfer
plate being provided with a plurality of louvers at certain
intervals along the heat transfer medium passing direction to
transfer heat of the heat transfer medium via the heat transfer
plate,
[0054] wherein a heat transfer medium inlet side edge of the louver
is formed so as to become thinner toward an upstream side of the
heat transfer medium passing direction.
[0055] In the heat transfer plate according to the fourth aspect of
the present invention, since the heat transfer medium inlet side
edge of the louver is formed so as to become thinner toward an
upstream side of a heat transfer medium flowing direction, the heat
transfer medium flows smoothly along the external surface of the
louver without causing turbulence. Thus, the flow resistance of the
heat transfer medium decreases, causing a decreased pressure loss,
which in turn results in an enhanced heat transfer rate. As a
result, excellent heat exchanging performance can be obtained.
[0056] In the fourth aspect of the present invention, it is
preferable to employ the following structure (17).
[0057] (17) The heat transfer fin as recited in the aforementioned
Item (16), wherein a heat transfer medium outlet side edge of the
heat transfer plate is formed so as to become thinner toward a
downstream side of the heat transfer medium passing direction.
[0058] The fifth aspect of the present invention employs the
following structure (18).
[0059] (18) A heat transfer fin, comprising:
[0060] a plurality of heat transfer plates disposed in parallel
with each other at certain intervals to form an air passage between
adjacent heat transfer plates, the heat transfer plate being
provided with a plurality of louvers at certain intervals along the
air passage to transfer heat of air passing through the air passage
via the heat transfer plate,
[0061] wherein a windward side edge of the louver is formed so as
to become thinner toward an upstream side of the air.
[0062] In this heat transfer fin according to the fifth aspect of
the present invention, in the same manner as mentioned above,
decreasing the pressure loss and enhancing the heat transfer rate
can be attained.
[0063] In the fifth aspect of the present invention, it is
preferable to employ the following structure (19).
[0064] (19) The heat transfer fin as recited in the aforementioned
Item (18), wherein the plurality of heat transfer fins are
connected such that adjacent heat transfer fins are connected to
form a corrugated fin.
[0065] The sixth aspect of the present invention employs the
following structure (20).
[0066] (20) A heat transfer fin, comprising:
[0067] a plurality of heat transfer plates disposed between a pair
of heat exchanging tubes arranged in parallel at a certain
distance, the plurality of heat transfer plates being disposed in
parallel with each other at certain intervals along a longitudinal
direction of the heat exchanging tube to form an air passage
between adjacent heat transfer plates, and the heat transfer plate
being provided with a plurality of louvers at certain intervals
along the air passage, whereby air passing through the air passage
exchanges heat with refrigerant passing through the heat exchanging
tubes,
[0068] wherein a windward side edge of the louver is formed so as
to become thinner toward a windward side of the air.
[0069] In this heat transfer fin according to the sixth aspect of
the present invention, in the same manner as mentioned above,
decreasing the pressure loss and enhancing the heat transfer rate
can be attained.
[0070] In the sixth aspect of the present invention, it is
preferable to employ the following structure (21).
[0071] (21) The heat transfer fin as recited in the aforementioned
Item (20), wherein the plurality of heat transfer fins are
connected such that adjacent heat transfer fins are connected to
form a corrugated fin.
[0072] In the fifth and sixth aspects of the present invention, it
is preferable to employ the following structures (22) to (27).
[0073] (22) The heat transfer fin as recited in any one of the
aforementioned Items (18) to (21), wherein a cross-sectional
contour configuration of the windward side edge of the louver is
formed into a curved configuration.
[0074] (23) The heat transfer fin as recited in the aforementioned
Item (22), wherein a cross-sectional contour configuration of the
windward side edge of the louver is formed into a semielliptic
configuration.
[0075] (24) The heat transfer fin as recited in the aforementioned
Item (22), wherein a cross-sectional contour configuration of the
windward side edge of the louver is formed into a semicircular
configuration.
[0076] (25) The heat transfer fin as recited in any one of the
aforementioned Items (18) to (21), wherein a cross-sectional
contour configuration of the windward side edge of the louver is
formed into a polygonal configuration.
[0077] (26) The heat transfer fin as recited in the aforementioned
Item (25), wherein the cross-sectional contour configuration of the
windward side edge of the louver is formed into a triangular
configuration with an acute-angled tip.
[0078] (27) The heat transfer fin as recited in any one of the
aforementioned Items (18) to (26), wherein a leeward side edge of
the louver is formed so as to become thinner toward a leeward side
of the air.
[0079] The seventh aspect of the present invention employs the
following structure (28).
[0080] (28) A heat transfer fin, comprising:
[0081] a heat transfer plate disposed parallel or nearly parallel
to a heat transfer medium passing direction, the heat transfer
plate being provided with a plurality of louvers at
certain:intervals along the heat transfer medium passing direction
to transfer heat of the heat transfer medium via the heat transfer
plate,
[0082] wherein a heat transfer medium inlet side edge of the heat
transfer plate and that of the louver are respectively formed so as
to become thinner toward an upstream side of the heat transfer
medium passing direction.
[0083] In the heat transfer plate according to the seventh aspect
of the present invention, since the heat transfer medium inlet side
edge of the heat transfer plate and that of the louver are
respectively formed so as to become thinner toward an upstream side
of a heat transfer medium flowing direction, the heat transfer
medium flows smoothly along the external surface of the heat
transfer plate and that of the louver without causing turbulence.
Thus, the flow resistance of the heat transfer medium decreases,
causing a decreased pressure loss, which in turn results in an
enhanced heat transfer rate. As a result, excellent heat exchanging
performance can be obtained.
[0084] In the seventh aspect of the present invention, it is
preferable to employ the following structure (29).
[0085] (29) The heat transfer fin as recited in the aforementioned
Item (28), wherein at least one of heat transfer medium outlet side
edges of the heat transfer plate and the louver is formed so as to
become thinner toward a downstream side of the heat transfer medium
passing direction.
[0086] The eighth aspect of the present invention employs the
following structure (30).
[0087] (30) A heat transfer fin, comprising:
[0088] a plurality of heat transfer plates disposed in parallel
with each other at certain intervals to form an air passage between
adjacent heat transfer plates, the heat transfer plate being
provided with a plurality of louvers at certain intervals along the
air passage to transfer heat of air passing through the air passage
via the heat transfer plate,
[0089] wherein a windward side edge of the heat transfer plate and
that of the louver are respectively formed so as to become thinner
toward an upstream side of the air.
[0090] In this heat transfer fin according to the eighth aspect of
the present invention, in the same manner as mentioned above,
decreasing the pressure loss and enhancing the heat transfer rate
can be attained.
[0091] In the eighth aspect of the present invention, it is
preferable to employ the following structure (31).
[0092] (31) The heat transfer fin as recited in the aforementioned
Item (30), wherein at least one of leeward side edges of the heat
transfer plate and the louver is formed so as to become thinner
toward a leeward side of the air.
[0093] The ninth aspect of the present invention employs the
following structure (32).
[0094] (32) A heat transfer fin, comprising:
[0095] a plurality of heat transfer plates disposed between a pair
of heat exchanging tubes arranged in parallel at a certain
distance, the plurality of heat exchanging plates being disposed in
parallel with each other at certain intervals along a longitudinal
direction of the heat exchanging tube to form an air passage
between adjacent heat transfer plates, the heat transfer plate
being provided with a plurality of louvers at certain intervals
along the air passage, whereby air passing through the air passage
exchanges heat with refrigerant passing through the heat exchanging
tubes,
[0096] wherein a windward side edge of the heat transfer plate and
that of the louver are respectively formed so as to become thinner
toward a windward side of the air.
[0097] In this heat transfer fin according to the ninth aspect of
the present invention, in the same manner as mentioned above,
decreasing the pressure loss and enhancing the heat transfer rate
can be attained.
[0098] In the ninth aspect of the present invention, it is
preferable to employ the following structure (33).
[0099] (33) The heat transfer fin as recited in the aforementioned
Item (32), wherein at least one of leeward side edges of the heat
transfer plate and the louver is formed so as to become thinner
toward a leeward side of the air.
[0100] The tenth aspect of the present invention employs the
following structure (34).
[0101] (34) A heat transfer fin disposed in a heat exchanging tube
through which refrigerant passes, the heat transfer fin comprising
a heat transfer plate arranged parallel to a refrigerant passing
direction to transfer heat of the refrigerant via the heat transfer
plate,
[0102] wherein a refrigerant inlet side edge of the heat transfer
plate is formed so as to become thinner toward an upstream side of
the refrigerant passing direction.
[0103] The tenth aspect of the present invention is directed to an
inner fin or the like to be disposed within a heat exchanging tube.
In this heat transfer plate, since the refrigerant inlet side edge
of the heat transfer plate is formed so as to become thinner toward
an upstream side of a refrigerant passing direction, the
refrigerant flows smoothly along the external surface of the heat
transfer plate without causing turbulence. Thus, the flow
resistance of the refrigerant decreases, causing a decreased
pressure loss, which in turn results in an enhanced heat transfer
rate. As a result, excellent heat exchanging performance can be
obtained.
[0104] In the tenth aspect of the present invention, it is
preferable to employ the following structure (35).
[0105] (35) The heat transfer fin as recited in the aforementioned
Item (34), wherein a refrigerant outlet side edge of the heat
transfer plate is formed so as to become thinner toward a
downstream side of the refrigerant passing direction.
[0106] The eleventh aspect of the present invention employs the
following structure (36).
[0107] (36) A heat transfer fin disposed in a heat exchanging tube
through which refrigerant passes, the heat transfer fin comprising
a plurality of heat transfer plates arranged parallel to a
refrigerant passing direction, the heat transfer plates being
provided with openings in a zigzag form to transfer heat of the
refrigerant via the heat transfer plates,
[0108] wherein a side edge of the opening of the heat transfer
plate facing an upstream side of the refrigerant passing direction
is formed so as to become thinner toward the upstream side of the
refrigerant passing direction.
[0109] In this heat transfer fin according to the eleventh aspect
of the present invention, in the same manner as mentioned above,
decreasing the pressure loss and enhancing the heat transfer rate
can be attained.
[0110] In the eleventh aspect of the present invention, it is
preferable to employ the following structure (37).
[0111] (37) The heat transfer fin as recited in the aforementioned
Item (36), wherein a side edge of the opening of the heat transfer
plate facing a downstream side of the refrigerant passing direction
is formed so as to become thinner toward the downstream side of the
refrigerant passing direction.
[0112] The twelfth aspect of the present invention employs the
following structure (38).
[0113] (38) A heat transfer fin disposed in a heat exchanging tube
through which refrigerant passes, the heat transfer fin comprising
a plurality of heat transfer plates arranged parallel to a
refrigerant passing direction, the heat transfer plates being
provided with openings in a zigzag form to transfer heat of the
refrigerant via the heat transfer plates,
[0114] wherein a refrigerant inlet side edge of the heat transfer
plate is formed so as to become thinner toward an upstream side of
the refrigerant passing direction, and
[0115] wherein a side edge of the opening of the heat transfer
plate facing the upstream side of the refrigerant passing direction
is formed so as to become thinner toward the upstream side of the
refrigerant passing direction.
[0116] In this heat transfer fin according to the twelfth aspect of
the present invention, in the same manner as mentioned above,
decreasing the pressure loss and enhancing the heat transfer rate
can be attained.
[0117] In the twelfth aspect of the present invention, it is
preferable to employ the following structures (39) and (40).
[0118] (39) The heat transfer fin as recited in the aforementioned
Item (38), wherein a refrigerant outlet side edge of the heat
transfer plate is formed so as to become thinner toward a
downstream side of the refrigerant passing direction.
[0119] (40) The heat transfer fin as recited in the aforementioned
Item (38) or (39), wherein a side edge of the opening of the heat
transfer plate facing a downstream side of the refrigerant passing
direction is formed so as to become thinner toward the downstream
side of the refrigerant passing direction.
[0120] The heat transfer fins according to the first to twelfth
aspects of the present invention can be preferably applied to heat
exchangers, evaporators for use in car air-conditioners, or
evaporators for use in car air-conditioners, as shown in the
following structures (41) to (43).
[0121] (41) A heat exchanger equipped with a heat transfer fin as
recited in any one of the aforementioned Items (1) to (40).
[0122] (42) An evaporator for use in car air-conditioners, the
evaporator being equipped with a heat transfer fin as recited in
any one of the aforementioned Items (1) to (40).
[0123] (43) A condenser for use in car air-conditioners, the
condenser being equipped with a heat transfer fin as recited in any
one of the aforementioned Items (1) to (40).
BRIEF DESCRIPTION OF DRAWINGS
[0124] FIG. 1 is a schematic partially broken perspective view
showing a fin portion and therearound of an evaporator according to
an embodiment of the present invention.
[0125] FIG. 2 is an enlarged cross-sectional view taken along the
line P-P in FIG. 1.
[0126] FIG. 3 is an enlarged cross-sectional view showing the
portion surrounded by the dashed line in FIG. 2.
[0127] FIG. 4 is an enlarged cross-sectional view showing a
windward side edge of a heat transfer plate/louver of a heat
transfer fin according to a first modification of the present
invention.
[0128] FIG. 5 is an enlarged cross-sectional view showing a
windward side edge of a heat transfer plate/louver of a heat
transfer fin according to a second modification of the present
invention.
[0129] FIG. 6 is an enlarged cross-sectional view showing a
windward side edge of a heat transfer plate/louver of a heat
transfer fin according to a third modification of the present
invention.
[0130] FIG. 7 is an enlarged cross-sectional view showing a
windward side edge of a heat transfer plate/louver of a heat
transfer fin according to a fourth modification of the present
invention.
[0131] FIG. 8 is a graph showing the relationship of the pressure
drop and the heat transfer rate with respect to the face velocity
of evaporators according to Example 1 and Comparative Example
1.
[0132] FIG. 9 is a graph showing the relationship of the pressure
drop and the heat transfer rate with respect to the face velocity
of evaporators according to Example 2 and Comparative Example
1.
[0133] FIG. 10 is a graph showing the relationship of the pressure
drop and the heat transfer rate with respect to the face velocity
of evaporators according to Example 3 and Comparative Example
1.
[0134] FIG. 11 is a graph showing the relationship of the pressure
drop and the heat transfer rate with respect to the face velocity
of evaporators according to Example 1 and Comparative Example
2.
[0135] FIG. 12 is a graph showing the relationship of the pressure
drop and the heat transfer rate with respect to the face velocity
of evaporators according to Example 4 and Comparative Example
2.
[0136] FIG. 13 is a graph showing the relationship of the pressure
drop and the heat transfer rate with respect to the face velocity
of evaporators according to Example 1 and Comparative Example
4.
[0137] FIG. 14 is a cross-sectional view showing a windward side
edge of a louver of a corrugated fin for conventional
evaporators.
BEST MODE FOR CARRYING OUT THE INVENTION
[0138] The present invention will be described in detail with
reference to the attached drawings.
[0139] FIG. 1 is a schematic partially broken perspective view
showing a fin portion and therearound of an evaporator for use in
car air-conditioners according to an embodiment of the present
invention. FIG. 2 is a schematic cross-sectional view of a fin
corresponding to a cross-section taken along the line P-P in FIG.
1. In the following explanation, the disposed direction of the heat
exchanging tube 51 and 52 will be regarded as an up-an-down
direction for easy understanding of the present invention.
[0140] As shown in FIGS. 1 and 2, a plurality of heat exchanging
tubes 51 and 52 each extending in the up-and-down direction (i.e.,
vertical direction) are disposed in parallel at a certain distance
in the right-and-left direction to form two rows, i.e., fore and
aft rows. Disposed between the heat exchanging tubes 51 and 52
adjacent in the widthwise direction of the evaporator is a
corrugated fin 53.
[0141] The corrugated fin 53 is provided with a plurality of thin
plate-like louver fins 54 as transfer plates extending in the fore
and aft direction and disposed in parallel at certain intervals in
the up-and-down direction. The adjacent louver fins 54 are
connected in turns to form a meandering shape. Between the adjacent
louver fins 54 and 54 of the corrugated fin 53, an air passage 56
extending in the fore and aft direction is formed. At the
operational status, air A introduced from the front side of the
evaporator passes through each air passage 56 and flows out of the
rear side thereof.
[0142] Each louver fin 54 is provided with a plurality of
cut-and-bent louvers 55 at certain intervals in the fore and aft
direction.
[0143] FIG. 3 is an enlarged cross-sectional view showing the
portion surrounded by the dashed line Q in FIG. 2. In other words,
FIG. 3 is an enlarged cross-sectional view of the front edge 55a of
each louver 55, i.e., the windward side edge (air inlet side edge)
relative to the air A to be introduced into the air passing passage
56. As shown in FIG. 3., the windward edge 55a of the louver 55 is
formed so as to become thinner toward the windward side.
Concretely, the windward side edge 55a of the louver 55 is formed
into a curved cross-sectional shape with a rounded tip end, or a
semielliptic shape formed by dividing an ellipse along the minor
axis.
[0144] In this embodiment, the front edge 54a of the louver fin 54
which is a portion surrounded by the dashed line R in FIG. 2, i.e.,
the windward side edge (air inlet side edge) of the louver fin 54,
is formed so as to become thinner toward the windward side as shown
by the reference numeral in parentheses in FIG. 3 in the same
manner as the aforementioned windward side edge 55a of the louver
55.
[0145] As a method for forming the front edge 54a and 55a of the
fin 54 and the louver 55, chemical processing such as etching as
well as mechanical processing such as pressing, cutting or
sharpening can be employed.
[0146] In this evaporator, air A is introduced into each air
passage 56 from the front side of the evaporator and flows out of
the rear side thereof. The air A exchanges heat with the
refrigerant passing through each heat exchanging tube 51 and 52
while passing through each air passage.
[0147] In this embodiment, the air A to be introduced in the air
passage 56 flows smoothly along the external surface of the
windward side edge 55a of the louver 55 without causing air
turbulence in stead of colliding against the windward side edge 55a
because of the tapered semielliptic configuration thereof.
Similarly, at the windward side edge 54a of the louver fin 54, the
air A flows smoothly along the external surface of the edge 54a
without causing air turbulence.
[0148] Since the air A flows smoothly without causing air
turbulence, the air resistance and the pressure loss decreases,
causing an enhanced heat transfer rate, which in turn results in
excellent heat exchanging performance.
[0149] In the aforementioned embodiment, although the
cross-sectional contour configuration of the front edge 54a/55a of
the fin 54/louver 55 is formed into a semielliptic shape, in the
present invention, the configuration is not limited to the above
embodiments. For example, the cross-sectional contour configuration
of the front edge can be a semicircular shape as shown in FIG. 4,
an isosceles triangular shape with an acute front edge as shown in
FIG. 5, a triangular shape with a single cut side as shown in FIG.
6, and a polygonal shape such as a trapezoidal shape with a tapered
end portion as shown in FIG. 7. Furthermore, the configuration can
be any combination of the aforementioned shapes shown in FIGS. 3 to
7. In short, it can be acceptable so long as the front edge 54a/55a
is formed so as to become thinner toward the tip end (windward side
end).
[0150] In the aforementioned embodiments, all of the louvers 55 are
formed to have a tapered front edge 55a respectively. However, in
the present invention, it can be acceptable that at least one of
the louvers 55 is formed to have a tapered front edge 55a.
Furthermore, in the aforementioned embodiments, both fins 54 and
louvers 55 are formed to have a tapered front edge 54a and 55a
respectively. However, in the present invention, it can be
acceptable that at least one of the fin front edge 54a and the
louver front edge 55a is formed to have a tapered edge.
[0151] Furthermore, in the aforementioned embodiments, the
explanation is directed to the case in which the present invention
is applied to an evaporator. However, the present invention is not
limited to the above embodiments, and can be similarly applied to
heat exchangers such as condensers, heater cores and radiators.
Furthermore, such heat exchangers are not limited to heat exchanger
for use in car air-conditioners, but can also be applied to heat
exchangers for use in room air-conditioners, refrigerators, another
refrigeration apparatuses, heaters, etc.
[0152] Furthermore, in the aforementioned embodiments, the
explanation is directed to the case in which the present invention
is applied to a corrugated fin as an example. However, the present
invention is not limited to the above embodiments, but can also be
applied, for example, to plate fins as independent heat transfer
plates to be disposed at certain intervals or skived fins formed by
skiving an external peripheral wall(s) of a heat exchanging
tube.
[0153] Furthermore, in the aforementioned embodiments, the
explanation is directed to the case in which the present invention
is applied to fins for transferring heat with air. However, the
present invention is not limited to the above embodiments, but can
also be applied to any fins for transferring heat with another heat
transfer medium such as refrigerant.
[0154] For example, in cases where the present invention is applied
to inner fins for transferring heat with refrigerant, the
refrigerant inlet side edge of the heat transfer plate (fin) to be
disposed in a heat exchanging tube is formed so as to become
thinner toward the upstream side of the refrigerant.
[0155] Furthermore, the present invention can be applied to offset
fins with heat transfer medium mixing openings formed in summit and
valley portions of a wavy heat transfer plate in a staggered
manner. Furthermore, the side edge of the opening of the offset fin
facing the upstream side of the heat transfer medium flowing
direction among the peripheral edge of the opening can be formed so
as to become thinner toward the upstream side.
[0156] In the aforementioned embodiments, the front side edge
(upstream side edge with respect to the heat transfer medium
flowing direction) of the fin (heat transfer plate) or its louver
is formed into a tapered configuration. However, the present
invention is not limited to the above. For example, the rear side
edge (the downstream side edge with respect to the heat transfer
medium flowing direction, the heat transfer medium outlet side
edge, or the leeward side edge) of the fin (heat transfer plate) or
its louver can be formed so as to become thinner toward the
rearward side (the downstream side, the outlet side or the leeward
side). Furthermore, in the aforementioned offset fin, the side edge
of the opening of the offset fin facing the downstream side of the
heat transfer medium flowing direction among the peripheral edge of
the opening can be formed so as to become thinner toward the
downstream side.
EXAMPLE
[0157] Hereinafter, examples related to the present invention will
be explained.
[0158] In accordance with the aforementioned embodiments,
evaporators provided with corrugated fins having various types of
plural louvers were examined.
Example 1
[0159] In Example 1, prepared was an evaporator provided with
corrugated fins as shown in FIG. 3 in which the windward side edge
of each fin and the windward side edge of each louver were
respectively formed into a semielliptic configuration.
[0160] Regarding this evaporator, the heat transfer rate and the
pressure loss with respect to the face velocity were measured by
computer simulation.
[0161] As Comparative Example 1, prepared was an evaporator
provided with conventional corrugated fins as shown in FIG. 14 in
which the windward side edge of each fin and the windward side edge
of each louver were respectively formed into a rectangular
cross-sectional shape perpendicular to the air flow direction. In
Comparative Example 1, the same measurements as in Example 1 were
carried out.
[0162] These measured results are shown in FIG. 8 in which the
solid line denotes Example 1 and the dashed line denotes
Comparative Example 1. As will be apparent from this graph, the
evaporator of Example 1 is smaller in pressure loss, higher in heat
transfer rate and therefore excellent in heat exchanging
performance as compared to Comparative Example 1. Especially,
Example 1 is excellent in performance at higher face velocity.
Examples 2 and 3
[0163] In Example 2, prepared was an evaporator provided with
corrugated fins as shown in FIG. 4 in which the windward side edge
of each fin and the windward side edge of each louver were
respectively formed into a semicircular cross-sectional shape.
[0164] In Example 3, prepared was an evaporator provided with
corrugated fins as shown in FIG. 5 in which the windward side edge
of each fin and the windward side edge of each louver were
respectively formed into an isosceles triangular cross-sectional
shape.
[0165] Regarding evaporators of Examples 2 and 3, the same
measurements as in Example 1 were carried out. The measured results
are shown in the graphs shown in FIGS. 9 and 10. Each of the graphs
also shows the measured results of the evaporator of Comparative
Example 1.
[0166] As shown in these graphs, the evaporator of Example 2 is
smaller in pressure loss, higher in heat transfer rate and
therefore excellent in heat exchanging performance as compared to
Comparative Example 1. Furthermore, Example 3 is excellent in heat
transfer rate especially at higher face velocity and therefore
excellent in heat exchanging performance, though no superiority can
be recognized in pressure loss.
Comparative Example 2
[0167] In Comparative Example 2, prepared was an evaporator
provided with corrugated fins in which the windward side edge of
each fin and the windward side edge of each louver were
respectively formed into a rectangular cross-sectional shape (see
FIG. 14), and the leeward side edges thereof were respectively
formed into a semielliptic cross-sectional shape as shown in FIG.
3.
[0168] Regarding this evaporator, the same measurements as in
Example 1 were carried out. The measured results are shown by the
dashed line in the graph shown in FIG. 11. In this graph, the solid
lines denote the measured results of the evaporator of Example
1.
[0169] This graph reveals the fact that the evaporator of Example 1
is smaller in pressure loss and higher in heat transfer rate as
compared with the evaporator of Comparative Example 2. In other
words, forming the windward side edge among both side edges of the
fin/louver into a tapered end enhances heat transferring
performance as compared with the case in which the leeward side
edge is formed into a tapered end.
Example 4
[0170] In Example 4, prepared was an evaporator provided with
corrugated fins in which the windward and leeward side edges of
each fin and the windward and leeward side edges of each louver
were respectively formed into a semielliptic cross-sectional shape
as shown in FIG. 3.
[0171] Regarding this evaporator, the same measurements as in
Example 1 were carried out, and the measured results are shown in
FIG. 12. In this graph, the dashed lines denote the measured
results of the evaporator of Comparative Example 2.
[0172] This graph reveals the fact that forming both edges of each
fin/louver into a tapered edge respectively can enhance the heat
exchanging performance as compared with the case in which only one
leeward side edge is formed into a tapered edge.
[0173] FIG. 13 shows the measured results of Example 4 with solid
lines and the measured results of Example 1 with dashed lines.
[0174] The graph reveals that the evaporator of Example 4 is
slightly small in pressure loss and slightly higher in heat
transfer rate as compared with Example 1. In other words, forming
both side edges of the fin/louver into a tapered end respectively
enhances heat transferring performance as compared with the case in
which only one windward side edge is formed into a tapered end.
[0175] As explained above, according to the present invention,
since a heat transfer medium inlet side edge of a heat transfer
plate and/or its louver is formed into a tapered end, a heat
transfer medium such as air can flow along the external periphery
of the heat transfer plate and/or its louver, causing smooth flow
without no turbulence. Accordingly, heat transfer medium flow
resistance and pressure loss can be decreased, causing an enhanced
heat transfer rate, which in turn results in excellent heat
exchanging performance.
[0176] The terms and expressions which have been employed herein
are used as terms of description and not of limitation, and there
is no intent, in the use of such terms and expressions, of
excluding any of the equivalents of the features shown and
described or portions thereof, but it is recognized that various
modifications are possible within the scope of the invention
claimed.
INDUSTRIAL APPLICABILITY
[0177] The present invention can be applied to, for example, a heat
transfer fin for heat exchangers such as evaporators or condensers
for use in car air-conditioners, and also relates to a heat
exchanger, an evaporator for use in car air-conditioners or a
condenser for use in car air-conditioners using such heat transfer
fins.
* * * * *