JPH0336480A - Heat exchanger - Google Patents

Abstract

PURPOSE:To improve defrosting efficiency by installing one or a plurality of continuous fins striding over at least two straight pipes which include a straight section of a refrigerant pipe on the outermost side on the heat source side for defrosting. CONSTITUTION:A vaporizer A is connected with a pipeline in a refrigerating cycle at both ends of a refrigerant pipe 2. At the same time, a heat source 9 is laid out on the bottom near the pipe so that the air may be circulated in the direction marked with the arrow W by a blower to cool the inside. During defrosting operation, the operation of refrigeration cycle is suspended and then electricity is supplied to a heat source 9. Then, the radiation heat thus generated prompts the melting of frost by directly heating a region subject to its heat rays. At the same time, the radiation heat given to the lower end of continuous fins 3 is transmitted to each refrigeration pipe 2 located upward by the fins concerned themselves and the radiation heat is further transmitted to independent fins 1 from the pipes, which makes it possible to transmit more efficiently the heat to the upper end of the vaporizer which the heat does not reach directly.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to heat exchangers used in refrigerators, refrigerated cars, evaporators of refrigeration showcases, etc., and in particular to heat exchangers that have a large number of independent fins and a serpentine refrigerant inserted therethrough. A fin with a pipe
Concerning a tube-shaped heat exchanger.

BACKGROUND ART When this type of heat exchanger is used for the above-mentioned purposes, it is used under conditions where the surface temperature is 0° C. or lower, and therefore the occurrence of frost formation is unavoidable. For this reason, as shown in Fig. 11, a heat source such as a heater (looo
) may be provided near the negative side of the heat exchanger (101). In the figure, (102) is a meandering refrigerant pipe, and (103) is a large number of independent fins inserted into the straight pipe portion of the vibrator.

Problems to be Solved by the Invention In this case, defrosting is performed by radiant heat from the heat source, heat conduction by the independent fins, and convection, but the farther away from the heat source (too), the more difficult the heat transfer becomes. Therefore, there was a drawback that the overall defrosting efficiency was not sufficient.This drawback becomes more noticeable as the number of meandering stages of the refrigerant pipe (102) increases, or in other words, as the distance from the heat source to the farthest part increases. Moreover, when the heat source (100') is operated for a long time to perform sufficient defrosting, another drawback arises in that power consumption increases.

The present invention was made in order to eliminate such drawbacks, and provides a heat exchanger that can reliably transmit heat from a heat source to an area that is not directly affected by radiant heat, and that can improve defrosting efficiency. The purpose is to

Means for Solving the Problems The above object is described with reference to the reference numerals in the drawings.A large number of independent fins (1) are provided in each straight pipe section (2a) of a meandering refrigerant vibrator (2). In the heat exchanger inserted and attached to the refrigerant pipe (2), the defrosting heat source (9)
At least two or more straight pipe parts including the outermost straight pipe part on the side (
This is achieved by a heat exchanger characterized in that a fin or a plurality of continuous fins (3) are provided across 2a).

The heat applied to the continuous fins (3) from the active heat source (9) is reliably transferred to each straight pipe section (2a) of the refrigerant pipe (2) in contact with the continuous fins by heat conduction inside the continuous fins, and then It is transmitted from the vibe (2) to the independent fin (1).

EXAMPLE Next, the present invention will be explained based on an example in which the present invention is applied to an aluminum evaporator for a freezer.

In Figures 1 and 2, (A) is an evaporator, (1) is an independent fin consisting of many small pieces, (2) is a serpentine refrigerant vibe, (3) is a continuous fin, and (4) ( 4) is a side plate, and (5) is an accumulator.

The refrigerant vibrator (2) is connected to the front and rear vibrator rows (21) (22).
) is meandering in the vertical direction in a shape having a straight pipe part (2a) and a U-bent part (2b). On the other hand, as shown in FIG. 5, the independent fin (1) has a pair of holes (6) (6) for inserting the front and rear refrigerant vibrators into the holes (6). is inserted into each straight pipe part (2a) of the refrigerant vibrator, and is externally packaged in parallel and in close contact with each straight pipe part (2a). Further, the continuous fin (3) consists of a single long fin, and as shown in Fig. 4, a plurality of notches (7) for fitting the refrigerant vibrator are formed on one side edge in the width direction. There is. As shown in FIGS. 1 and 3, the continuous fins (3) are connected to the straight pipe portion (2a) of the refrigerant pipe (2).
In the middle part excluding both ends, three pieces are arranged vertically near both ends and near the center, and each straight pipe part (2a ) are fitted so as to straddle each straight pipe section (2a).

To construct the evaporator (A), first, as shown in FIG. 5, a pair of refrigerant pipe insertion holes (6) are opened before and after a large number of independent fins (1). Then, arrange these fins so that they are parallel to each other, and insert U-shaped refrigerant pipes (2) into each of the holes (6) as shown in Figure 6, and expand them if necessary. It shall be in close contact with the periphery of the hole all the way around. At this time, the independent fins (1) are arranged so as to avoid the meandering portion of the refrigerant pipe (2), as shown in FIG.

Next, the refrigerant pipe (2) is connected to each independent fin (1).
The part having the groups is bent in a meandering manner so as to become a straight pipe part (2a). In order to facilitate such bending and to prevent the vibrator from being crushed due to bending, as shown in FIGS. It is also recommended to pre-provide a plurality of annular grooves (8). The shape of the groove (8) preferably has a depth h
It is preferable to set the groove pitch to 0.2 to 2 m, the width m to 1 to 6 rN11, and the groove pitch to 3 to 15 IIll. The bent pipe (2) has one part of the U-ben (2b)
Attach the side plates (4) (4) to (2b).

Next, a pipe fitting notch (7) is formed on the - side edge of the independent fin (1), and the front pipe row (2) is inserted into this notch (7).
The vertical straight pipe sections (2a) of 1) are fitted, and the continuous fins (3) are tightly attached across the straight pipe sections (2a) to form the desired evaporator (A).

The evaporator (A) connects both ends of the refrigerant pipe (2) to the piping system of the refrigeration cycle, which includes a compressor that compresses the refrigerant and a condenser that liquefies the compressed refrigerant, and connects it to a heating element such as a heater. A heat source (9) is placed close to the lower end of the evaporator (A), and the arrow (W) in FIG.
The inside of the refrigerator is cooled by circulating air using a blower. And when defrosting, after stopping the operation of the above refrigeration cycle,
The heat source (9) is energized. Then, due to the radiant heat emitted from this, the area covered by the heat rays is directly heated, and the frosting progresses to melt. In addition, the radiant heat applied to the lower end of the continuous fins (3) is transmitted by the fins themselves to each refrigerant vibrator (2) above, and further transmitted from the vibrator to the independent fins (1), so that the radiant heat is not directly transmitted. The heat is efficiently transferred to the upper end of the evaporator, which is not reached by the heat, and the defrosting effect by convection is also added, achieving an efficient defrosting effect for the entire evaporator.

In the above embodiment, the vibration fitting notch (7) was provided on the - side edge of the continuous fin (3) and attached to the front vibration row (21), but it was not attached to the rear vibration row (22). It's okay. Alternatively, as shown in FIGS. 9 and 10, the notches (7') for fitting the vibrator are provided on both sides of the continuous fins (3'), and the continuous fins (3') are connected to the front and rear refrigerant. The front and rear hook vibrators (2') may be interposed between the rows of vibrators and fitted into the notches (7') thereof. In addition, continuous fins do not necessarily have to be placed across all straight pipe sections in the vertical direction of the refrigerant pipe, but only on the straight pipe section at the lowest end on the heat source side and the straight pipe section adjacent thereto. It may be placed over two or more straight pipe sections including the straight pipe section on the heat source side. Furthermore, the number of continuous fins does not necessarily have to be two or more, but may be one or more.

Effects of the Invention As described above, the present invention provides a heat exchanger in which a large number of independent fins are attached to each straight pipe portion of a meandering refrigerant pipe by penetrating the refrigerant pipe. It is characterized by one or more continuous fins being provided across at least two or more straight pipe parts including the outermost straight pipe part on the heat source side, so when defrosting is performed, the heat source The radiant heat applied to the continuous fins can be directly transmitted to each straight pipe part in contact with the continuous fins by thermal conduction of the continuous fins themselves, and can further be transmitted from the straight pipe parts to the independent fins. Therefore, sufficient heat can be transmitted and imparted to areas that are not directly affected by radiation from the heat source, and the defrosting efficiency of the entire heat exchanger can be improved. In addition, even with a large heat exchanger with a large number of meandering stages, heat can be reliably transferred over a wide range, and effective defrosting can be performed. Furthermore, since there is no need to ensure a long defrosting time, it is possible to reduce the power consumption for driving the heat source.

[Brief explanation of the drawings] Figure 1 is a front view of the entire heat exchanger, Figure 2 is a side view thereof, Figure 'M43 is a sectional view taken along the line ■-■ in Figure 1, and Figure 4 is a continuous fin cross-sectional view. Figure 5 is a side view showing the shape of the independent fins, Figure 6 is a plan view of the arrangement of the independent fins during assembly and a refrigerant pipe inserted into it, Figure 7 is the U-bend formation plan. Front view of part (bending part), No. 8
The figure is an enlarged front view showing a part of Figure 7, Figures 9 and 10.
The figures show other embodiments; FIG. 9 is a side view of the continuous fin, FIG. 10 is a sectional view of the continuous fin in FIG. The figure is a schematic front view of a conventional heat exchanger. (1)...Independent fin, (2)...Refrigerant pipe, (
2a>... Straight pipe part, (3) (3')... Continuous fin, (7) (7')... Notch part, (9)... Heat source. that's all

Claims (1)

[Claims] In a heat exchanger in which a large number of independent fins (1) are attached to each straight pipe part (2a) of a meandering refrigerant pipe (2) by passing through the refrigerant pipe, defrosting of the refrigerant pipe (2) is performed. A heat exchanger characterized in that one or more continuous fins (3) are provided spanning at least two or more straight pipe parts (2a) including the outermost straight pipe part on the heat source (9) side. vessel.