JP2002147894A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat exchanger capable of restraining the deterioration of heat exchanging performance upon frosting and, further, capable of shortening a defrosting time. SOLUTION: The fins 7 of the heat exchanger 2 are extended in the shape of a belt and a plurality of rows of through holes 71, 72, 73, 74, 81, 82, 83, 84 are formed on a fin along the longitudinal direction Y of the same. The arrangement of the through holes 71, 72, 73, 74, 81, 82, 83, 84 are set so as to be zigzag between rows neighbored to each other while the same in respective rows is set so as to be zigzag. Heat transfer tubes are mounted so as to be penetrated through respective through holes 71, 72, 73, 74, 81, 82, 83, 84 of the fins 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a heat exchanger. More specifically, it is inserted into the refrigerant circuit of the air conditioner,
The present invention relates to a cross-fin coil type heat exchanger that exchanges heat between a refrigerant circulating in the refrigerant circuit and ambient air.

[0002]

2. Description of the Related Art This type of heat exchanger has a plurality of fins arranged so as to be stacked at a predetermined interval from each other between a pair of tube sheets. As shown in FIG. 3, each of the fins 107 has a substantially band shape, and is formed in two rows along the longitudinal direction (Y direction) to form through holes 17 for inserting heat transfer tubes.
1,172,173,174, ..., 181,182,1
83, 184,... (All have a diameter of D ₁₀₁ ). One row of through holes 171, 172, 173, 1
The center O ₁₇₁ , O ₁₇₂ , O ₁₇₃ , O ₁₇₄ ,.
A plurality of straight lines T ₁₀₁ , T ₁₀₂ , T ₁₀₂ , extending in the X direction parallel to each other at a predetermined pitch P ₁₀₁ with the center line L _{101 of the} row extending in the direction
It is on the intersection with _T103 , _T104 , .... Also, the centers O ₁₈₁ , O ₁₈₂ , O ₁₈₃ , O ₁₈₄ ,... Of the through holes ₁₈₁ , ₁₈₂ , ₁₈₃ , ₁₈₄ ,... Of the adjacent row are the same as the center line L _{102 of the} row extending in the Y direction. A plurality of straight lines T ₁₁₁ , T ₁₁₂ , T extending in the X direction in parallel with each other at a pitch P _101
113 , T ₁₁₄ ,... Straight lines T ₁₀₁ , T ₁₀₂ ,
_T103 , _T104 , ... and straight lines _T111 , _T112 , _T113 , _T114 ,
.. Are mutually (1/2) pitches (= P ₁ ) in the Y direction.
_01/2) are shifted by the amount given, this result, the through holes 171, 172, 173, and 174 of the fins 107, ..., 181,
, 182, 183, 184,... Are arranged in a staggered manner between adjacent rows. Note that _P102 is a pitch between columns.

A plurality of such fins 107 are stacked at a predetermined interval in a direction perpendicular to the paper surface of FIG. 3, and a heat transfer tube is inserted through a corresponding through hole of each fin 107 and attached. During operation, the refrigerant flows through the heat transfer tubes, and the surrounding air flows through the gaps between the fins 107 in substantially the X direction. Thereby, heat exchange between the refrigerant and the surrounding air is performed via each heat transfer tube and each fin.

[0004]

Meanwhile, in the outdoor heat exchanger, when the outside air temperature is low during the heating operation, frost may adhere to the front edge 107f side of the fin (the side where outside air flows in). For this reason, there is a tendency that the ventilation resistance increases, the air volume becomes insufficient, and the heat exchange performance decreases. Also,
When the defrosting operation is performed because the outdoor heat exchanger is frozen, the frost on the front edge 107f side of the fin is less likely to be thawed, and the defrosting time tends to be longer.

Accordingly, an object of the present invention is to provide a heat exchanger capable of suppressing a decrease in heat exchange performance during frost formation and shortening a defrosting time.

[0006]

According to a first aspect of the present invention, there is provided a heat exchanger comprising: a fin having a plurality of rows extending in a longitudinal direction and having a plurality of rows of through holes; A heat exchanger having a heat transfer tube inserted through each of the through-holes of the fin, wherein the arrangement of the through-holes of the fin is set in a staggered manner between rows adjacent to each other, and It is characterized in that the rows are set in a staggered manner.

In the heat exchanger according to the first aspect, the arrangement of the through holes of the fins is set in a staggered manner between adjacent rows, and is set in a staggered manner in each row. As a result, as compared with the conventional case where the through holes of the fins are only arranged in a staggered manner between the rows adjacent to each other (this is called “simple staggered shape”), the front edge side of the fins (this is called “simple staggered shape”). In the row on the side where air flows in), the spacing between the through holes, that is, the spacing between the heat transfer tubes is widened. Therefore, when frost adheres to the leading edge side of the fins due to the low outside air temperature during the heating operation, it is possible to suppress an increase in ventilation resistance and a decrease in heat exchange performance. Further, in this heat exchanger, there is a through hole (that is, a heat transfer tube) closer to the front edge of the fin than in the simple staggered shape. Therefore, when performing the defrosting operation because the outdoor heat exchanger is frozen, the frost on the leading edge side of the fin is easily defrosted, and the defrosting time is shortened. Further, as described above, the interval between the through holes, that is, the interval between the heat transfer tubes in the row on the leading edge side of the fins is widened, so that the molten water can be efficiently discharged.

According to a second aspect of the present invention, in the heat exchanger according to the first aspect, the pitch of the through holes in the longitudinal direction is the same in each row, and the through holes belonging to the rows adjacent to each other are formed. The positions in the longitudinal direction are shifted by (分) pitch, and the through holes belonging to one row are alternately shifted in a direction perpendicular to the longitudinal direction by a predetermined offset amount from the center line of the row. It is characterized by having.

In the heat exchanger according to the present invention, the pitch of the through holes in the longitudinal direction is the same in each row, and the through holes belonging to each row are separated from the center line of the row by a predetermined offset amount. Are alternately shifted in a direction perpendicular to the direction.
That is, the staggered arrangement of the through holes of the fins in each row is offset (displaced) in a direction perpendicular to the longitudinal direction.
Just realized. Therefore, the design of the heat exchanger,
Manufacturing becomes easy, and the heat exchanger is manufactured with high accuracy.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a heat exchanger according to the present invention will be described in detail with reference to the illustrated embodiments.

FIG. 1 shows the structure of a heat exchanger 22 according to one embodiment. FIG. 2A shows the heat exchanger 22 as viewed from the front (the side where air flows in), and FIG.
(C) is a view taken along line CC in FIG. (A).

As shown in FIG. 1A, this heat exchanger 2
2 is a predetermined distance between the pair of left and right tubesheets 51 and 52.
Made of aluminum arranged to be separated by a gap
Have a plurality of fins 7, 7,. In FIG. 1 (c)
As shown, each fin 7 is substantially band-shaped,
Heat transfer tube insertion in two rows along the direction (Y direction)
, 81, 82, through holes 71, 72, 73, 74,.
83, 84,... Are formed. Straight through these through holes
All diameters are D₁Is set to One row of through holes
The center O of 71, 72, 73, 74, ...₇₁, O₇₂, O₇₃,
O₇₄,... Indicate the center line L of the row extending in the Y direction.₁And prescribed
Pitch P₁A plurality of straight lines T extending in the X direction ₁, T_Two, T_Three,
T_Four, ... from the intersection with + X by a fixed offset amount Δ
And -X directions. Where X
⊥Y. Also, the through holes 81, 8 in the row adjacent to it
Center O of 2,83,84, ...₈₁, O₈₂, O₈₃, O₈₄,…
Is the center line L of the column extending in the Y direction_TwoAnd the same
Switch P₁Multiple straight lines extending in the X direction parallel to each other
T₁₁, T₁₂, T₁₃, T₁₄A certain off from the intersection with
Position shifted alternately in + X direction and -X direction by set amount Δ
It is in. As a result, the through holes 71, 72, 7
, 81, 82, 83, 84,...
Are arranged in a zigzag pattern. Further, a straight line T₁,
T_Two, T_Three, T_Four, ... and straight line T ₁₁, T₁₂, T₁₃, T₁₄,…
Means (1/2) pitch (= P₁/
2), and as a result, the through holes 7 of the fins 7
1, 72, 73, 74, ..., 81, 82, 83, 84,
… Are arranged in a zigzag pattern between adjacent rows
You.

The staggered arrangement of the through holes of the fins 7 in each row is realized only by offsets in the ± X directions. Therefore, the heat exchanger 22 can be easily designed and manufactured based on the conventional simple staggered shape, and the heat exchanger 22 can be manufactured with high accuracy.

Specific dimensions are, for example, the diameter D of the through hole.
₁ = 7 mm, the step pitch P _{1 of} the through holes = 24 m, the row pitch P ₂ of the through holes = 16 mm, and the offset amount Δ = 2 mm of the through holes in each row. Since there is a relationship of Δ≪P ₂ between the offset amount Δ of the through holes in each row and the row pitch P ₂ of the through holes, the through holes 71, 72, 73, 74 along the center line L _1. , ... and columns of through holes 81,82,83,8 along the centerline L ₂ adjacent thereto
The columns of 4,... Are clearly distinguished from each other.

As shown in FIG. 1 (a), a plurality of such fins 7 are stacked on the left and right at predetermined intervals, and a heat transfer tube (straight tube) 61 is inserted into a corresponding through hole of each fin 7. You. Then, as shown in FIG.
One ends are connected by a U-shaped tube 62 to form one meandering refrigerant path 60. In operation, the refrigerant path 6
0, that is, the refrigerant flows through each heat transfer tube 61, and the surrounding air flows through the gap between the fins 7 in the substantially X direction (see FIG. 1C). Thereby, heat exchange between the refrigerant and the surrounding air is performed via each heat transfer tube 61 and each fin 7.

The heat exchanger 22 is used, for example, as an outdoor heat exchanger of a separate type air conditioner as shown in FIG. In this air conditioner, the outdoor unit 20 and the indoor unit 1 are connected by refrigerant pipes 11 and 12. The outdoor unit 20 includes an outdoor heat exchanger 22, an outdoor fan 26, a compressor 2
3, an accumulator 24 for performing gas-liquid separation, and a four-way switching valve 25 for switching the direction of the refrigerant.

During the heating operation, the compressor 23 and the outdoor fan 26 are operated, and the refrigerant discharged by the compressor 23 is changed as shown by a broken line in FIG. , The four-way switching valve 25 and the pipe 11 are sent to the indoor heat exchanger 2, and the indoor heat exchanger 2 is returned to the compressor 23 through the pipe 12, the outdoor heat exchanger 22, the four-way switching valve 25 and the accumulator 24. On the indoor unit 1 side, the indoor fan 3 is operated. This allows
The heat taken in by the outdoor heat exchanger 22 is transported to the indoor heat exchanger 2 by the refrigerant, and is released into the room by the blown air generated by the indoor fan 3.

It is assumed that frost adheres to the front edge 7f side of the fin 7 of the outdoor heat exchanger 22 during the heating operation because the outside air temperature is low. At this time, in the outdoor heat exchanger 22, FIG.
As shown in (c), the arrangement of the through-holes of the fins 7 is set in a staggered manner between adjacent rows, and is set in a staggered manner in each row. , The spacing between the through holes 71, 72, 73, 74,..., That is, the spacing between the heat transfer tubes 61, 61,. Therefore, an increase in ventilation resistance in the outdoor heat exchanger 22 can be suppressed, and a decrease in heat exchange performance can be suppressed.

When the outdoor heat exchanger 22 is frozen, the operation shifts to a defrosting operation. That is, the outdoor fan 26 and the indoor fan 3 are stopped, and the four-way switching valve 25 is switched to circulate the refrigerant in the direction shown by the solid line in FIG. 2 (the same direction as in the cooling operation). That is, the refrigerant discharged by the compressor 23 is supplied to the four-way switching valve 25 and the outdoor heat exchanger 2.
2. It is sent to the indoor heat exchanger 2 through the pipe 12, and is returned from the indoor heat exchanger 2 to the compressor 23 through the pipe 11, the four-way switching valve 25, and the accumulator 24. Thereby, the outdoor heat exchanger 22 is heated by the heat carried by the refrigerant from the indoor side. Here, in the outdoor heat exchanger 22, the through holes 72 closer to the front edge 7f of the fin 7 than the simple staggered shape are used.
74 (ie, heat transfer tubes) are present. Therefore, the frost on the front edge 7f side of the fin 7 can be easily thawed, and the defrosting time can be reduced. Also, as described above, the through holes 71, 72, 73, 7
, That is, the intervals between the heat transfer tubes 61, 61,... Are widened, so that the molten water can be efficiently discharged. In addition,
When the freezing of the outdoor heat exchanger 22 is released, the defrosting operation is terminated, and the operation shifts to the original heating operation.

As described above, according to the outdoor heat exchanger 22, the average capacity can be improved in the heating operation in a state where the outside air temperature is low.

In this embodiment, the through-holes of the fins are arranged in two rows, but may be arranged in more rows.

[0022]

As is clear from the above, according to the heat exchanger of the first aspect, it is possible to suppress a decrease in heat exchange performance during frost formation.
Moreover, the defrosting time can be reduced.

In the heat exchanger of the second aspect, the staggered arrangement of the through holes of the fins in each row is realized only by an offset (displacement) in a direction perpendicular to the longitudinal direction. The design and manufacture of the heat exchanger can be performed easily, and the heat exchanger can be manufactured with high accuracy.

[Brief description of the drawings]

FIG. 1 is a diagram showing a structure of a heat exchanger according to an embodiment to which the present invention is applied. (A) is a view of the heat exchanger 22 as viewed from the front (the side where air flows in), and (b) is a view of FIG.
(C) is a view taken along line CC in FIG. (A).

FIG. 2 is a diagram showing a refrigerant circuit of an air conditioner including the heat exchanger of FIG. 1 in an outdoor unit.

FIG. 3 is a view showing fins of a conventional heat exchanger.

[Explanation of symbols]

7 Fin 7f Front edge 22 Outdoor heat exchanger 71, 72, 73, 74, 81, 82, 83, 84 Through hole

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Junichiro Tanaka 2 Okamotocho, Okamoto-cho, Kusatsu-shi, Shiga 1000 Daiya Kogyo Co., Ltd. Shiga Works F term (reference) 3L103 AA19 BB42 CC18 CC22 DD06

Claims (2)

[Claims] 1. A plurality of through holes (71, 72, 73, 74; 8) extending in a belt shape and arranged in a plurality of rows along a longitudinal direction (Y).
1,82,83,84) formed fins (7),
Each through hole (71, 72, 73, 7) of the fin (7)
4; 81, 82, 83, 84), a heat exchanger (2) having a heat transfer tube (61) attached thereto, wherein the fin (7) has through holes (71, 72, 73, 74). ;
81, 82, 83, 84) are arranged in a staggered manner between adjacent rows, and are arranged in a staggered manner in each row. 2. The heat exchanger according to claim 1, wherein said through holes (71, 72, 73, 74; 81, 82, 8).
3, 84) are the same in the longitudinal direction (P ₁ ) in each row, and the through holes (71, 7) belonging to the rows adjacent to each other
2, 73, 74; 81, 82, 83, 84) are shifted by (１ ／) pitch in the longitudinal direction, and the through holes (71, 72, 73, 74; 81,
82 83) has a feature that the offset alternately to the center line of the column (L _1, L ₂₎ from a predetermined offset amount (delta) only the direction perpendicular to the longitudinal direction (X) Heat exchanger.