JP2551072B2 - Heat exchanger - Google Patents

Description

The present invention relates to a heat exchanger and can be used as, for example, an evaporator in a refrigeration cycle.

(Technical background) The inventors of the present application have previously proposed a heat exchanger as shown in FIG. 2 in Japanese Patent Application No. 62-255250.

As shown in Japanese Utility Model Publication No. 53-32378, the heat exchanger shown in FIG. 2 has a pair of plates each having a U-shaped groove and tank recesses at both ends of the U-shaped groove. The unit 110 is formed, and a plurality of layers are stacked on the unit 110. By stacking the plurality of units 110, a plurality of U-shaped tubes 112 and tank portions 120a to 120d are formed at both ends of the tubes 112, and corrugated fins bent in a wave shape are provided between the tubes 112. 114 are arranged.

The tank parts 120a to 120b are substantially cylindrical, and an inlet pipe 130 for introducing a refrigerant into the tank part 120a is arranged at one end of the tank part 120a. This inlet pipe 130
Has a channel 132 of a dogleg shape bent at a substantially right angle, and a fluid outlet 131 that opens in the axial direction of the tank portion 120a is opened to the side of this channel 132.

In the heat exchanger shown in FIG. 2, the refrigerant flowing from the inlet pipe 130 into the tank portion 120a flows through the tube 112 and then into the tank portion 120b. Then, it flows into the tank portion 120c arranged coaxially with the tank portion 120b, and the tube 11
2, Outflow from the outlet pipe 145 via the tank portion 120d.

[Problems to be Solved by the Invention]

However, in the heat exchanger 100 having the above-mentioned inlet pipe 130, the refrigerant flowing in the inlet pipe 130 is bent at the bent portion 130a as shown in FIG. It becomes a flow. as a result,
The refrigerant flowing from the fluid outlet 131 into the tank portion 120a diverges in the tank portion 120a as shown in FIG.
It is not evenly distributed to the tubes 112, but is distributed unevenly to the tubes located near the fluid outlet 131. At this time, the air temperature after passing through the heat exchanger 100 is such that heat exchange is not sufficiently performed as it passes through a tube farther from the inlet portion of the tank portion 120a, which causes performance deterioration.

In FIG. 4, reference numeral 121 is a communication hole that connects the tank portion 120a and each tube 112.

[Means for solving the problem]

Therefore, in the present invention, a narrowed portion that narrows the flow path in the bending direction is formed at a position between the bent portion of the generally V-shaped inlet pipe connected to the inlet tank portion and the fluid outlet.

[Action and effect]

As a result, the fluid bent at the bent portion is contracted by the throttle portion, and the flow is directed toward the fluid outlet. As a result, since the fluid does not become a swirling flow as in the conventional case, the fluid can well flow into the inside of the inlet tank portion from the fluid outlet, and is evenly distributed to each tube.

〔Example〕

Next, an example in which the present invention is used as an evaporator in a refrigeration cycle will be described.

The heat exchanger 100 as a whole is as shown in FIG. 2 and as described above. However, the inlet tank defined by the present invention corresponds to the tank portion 120a, and the outlet tank corresponds to the tank portion 120b.

The inlet pipe 130 used in this embodiment is shown in FIG. The inlet pipe 130 has a first recess 141 having an oval shape that follows the cross-sectional shape of the tank portion 120a, and a second recess 142 that has an oval shape that follows the cross-sectional shape of the tank portions 120b and 120c.

The first recess 141 is provided with a fluid outlet 131 that opens toward the tank portion 120a and that introduces a refrigerant into the tank portion 120a. The second recess 142 is provided with a communication hole 133 that connects the tank portion 120b and the tank portion 120c.

The flow path 132 communicating with the first recess 141 is bent substantially at a right angle by bending the inlet pipe 130 at the bent portion 130a in a substantially V shape. And this bent portion 130a
A narrowed portion 140 that narrows the flow path 132 in the flow path bending direction is formed between the flow path 132 and the fluid flow outlet 131, and the refrigerant flowing in the flow path 132 is, as indicated by an arrow R in the figure, a fluid flow outlet. Constrict toward 131. As a result, the refrigerant smoothly flows out of the fluid outlet 131 without forming a swirling flow.

FIG. 1 is a sectional view taken along the center line of the inlet pipe 130. The inlet pipe 130 is formed by joining the plates shown in this figure to each other and joining the hatched portions in the figure. However, the fluid outlet 131 is not formed in the first recess 141 of the other plate facing each other.

FIGS. 6 and 7 show the measured outlet air temperatures of the evaporator using the conventional inlet pipe shown in FIG. 3 and the evaporator of this embodiment. The horizontal axis indicates the horizontal position of the evaporator, and the vertical axis indicates the air temperature. Also, FIGS. 6 and 7
In the figure, A indicates the outlet air temperature at the upper end of the evaporator, B indicates the middle portion, and C indicates the outlet air temperature at the lower end.

As can be seen from these figures, in the conventional evaporator, the temperature difference at the upper end, the middle, and the lower end and the temperature difference in the width direction are large, whereas in the present embodiment, the temperature difference is large. It has been reduced.

In the inlet pipe 130 shown in FIG. 1, the fluid outlet 131 is a simple opening, but as shown in FIG.
A cylindrical nozzle 135 projecting toward the inside of the tank portion 120a may be formed around the. With this nozzle 135, the refrigerant can be jetted farther from the tank portion 120a. The plate forming the inlet pipe is formed by press molding.

[Brief description of drawings]

1 is a sectional view of an inlet pipe of an embodiment of the present invention, FIG. 2 is a perspective view of an evaporator, FIG. 3 is a sectional view of a conventional inlet pipe, and FIG. 4 is a sectional view showing the operation of a conventional inlet pipe. FIG. 5 is a diagram showing an outlet air temperature of a conventional example, FIGS. 6 and 7 are diagrams showing an outlet air temperature of a conventional example, and an embodiment of the present invention, FIG.
The figure is a sectional view showing another embodiment of the inlet pipe. 112 …… tube, 114 …… fin, 120a to 120d …… tank part, 130 …… inlet pipe, 131 …… fluid outlet, 140 …… throttle part.

Claims (1)

(57) [Claims] 1. An inlet tank having a tubular shape, a plurality of tubes having one end connected to the inlet tank, and a tubular outlet tank connected to the other end of the tubes, wherein one end of the inlet tank is provided. On the side, an inlet pipe for introducing the heat exchange fluid into the inlet tank is connected so as to be substantially orthogonal to the axis of the inlet tank, and the inlet pipe is a channel bent in a substantially V shape. And a fluid outlet that is lateral to the flow passage and opens in the axial direction of the inlet tank, and between the bent portion of the flow passage and the fluid outlet and in the bending direction of the flow passage. A heat exchanger having a narrowed portion for guiding a fluid to be heat-exchanged flowing in the flow passage toward the fluid outlet, by narrowing the flow passage.