JPH0674954B2 - Heat exchanger - Google Patents

Description

TECHNICAL FIELD The present invention relates to a heat exchanger used in a low temperature device such as a helium refrigerating device.

[Conventional technology]

Fig. 5 is a partially cutaway sectional view showing a conventional low temperature heat exchanger shown in, for example, CRYOGENIX. P552, issued in September 1979 (CRYOGENICS, SEPTEMBER 1979, P552), and Fig. 6 is FIG. 1 is an enlarged view of a main part of the figure, in which (1) is a heat transfer body in which copper wire mesh (1a) that is a disk-shaped heat transfer plate is laminated, and is, for example, a first refrigerant such as low-pressure helium gas. (2) flows in the heat transfer body (1) in the direction of the arrow in the figure. (3) is a solder (6) which is a brazing material on the outer peripheral wall surface of the heat transfer body (1)
Tubes that are joined in a spiral shape by using (for example, copper heat transfer tubes)
The second refrigerant (4) such as high-pressure helium gas flows in the inside in the direction of the arrow in the figure. (5) is a container for accommodating the heat transfer plate (1) and the heat transfer tube (3).

The low-temperature heat exchanger configured as described above is housed in a vacuum container (not shown) together with other low-temperature components, and is a high-pressure gas (for example, a second refrigerant (4) supplied from the compressor (for example, 300K, 16atm) is introduced into the heat transfer tube (3). On the other hand, the low-pressure gas (for example, 80K, 1atm) that is the first refrigerant (2) returning from the low temperature side has a flow rate ratio of 1: 1 in the wire mesh (1a) from the direction facing the second refrigerant (4). Shed Then, the first refrigerant (2) flowing in the axial direction of the heat transfer body (1)
As shown in FIG. 6, the metal mesh (1a), which is a heat transfer plate, diffuses and the contact area with the metal mesh (1a) increases. As a result, the cold heat causes the wire (1a) of the metal mesh (1a) and the solder (6) to cool. The second refrigerant (4) is cooled and discharged from the heat transfer tube (3) by heat conduction to the tube wall of the heat transfer tube (3).

[Problems to be solved by the invention]

The conventional heat exchanger configured as described above is shown in FIG. 6 because the heat transfer tube (3) is directly wound around the outer peripheral wall of the heat transfer body (1) by using the solder (6). As described above, since only a part of the wire of the wire mesh (1a) is in contact with the heat transfer tube (3) and the solder (6), the contact area between the heat transfer tube (3) and the heat transfer body (1) is small. There is a problem that the heat transfer efficiency is poor.

The present invention has been made to solve the above problems, and an object thereof is to obtain a heat exchanger having high heat transfer efficiency by completely making thermal contact between a heat transfer tube and a heat transfer plate. .

[Means for solving problems]

The heat exchanger according to the present invention has a heat transfer member formed by stacking heat transfer plates made of a material having a high heat conductivity, and a heat transfer member having a high heat conductivity provided in surface contact with an outer peripheral wall surface of the heat transfer member. A thin-walled intermediate heat transfer body, and a heat transfer tube made of a material having a high thermal conductivity, which is spirally joined to the outer peripheral wall surface of the intermediate heat transfer body with a brazing filler metal. On the other hand, the heat transfer plates are arranged in a plurality of stages, and heat is exchanged between the medium flowing in the axial direction of the heat transfer body and the medium flowing in the heat transfer tube.

[Action]

In the heat exchanger of the present invention, since the wire of the heat transfer plate is in contact with the intermediate heat transfer body and the intermediate heat transfer body is in contact with the heat transfer tube, the contact between the heat transfer tube and the heat transfer body is Area increases,
The heat transfer efficiency is improved.

Further, since the intermediate heat transfer body is formed of a thin material having a high thermal conductivity, the heat transfer cross-sectional area of the heat transfer body of the intermediate heat transfer body in the axial direction is small, and the axial direction of the heat transfer body is reduced accordingly. While the thermal resistance is high, the distance between the heat transfer element and the heat transfer tube is short, which reduces the heat resistance in the radial direction of the heat transfer element, and therefore the heat between the heat transfer element and the heat transfer tube. Transfer efficiency is further improved.

Further, since the heat transfer plates are arranged in a plurality of stages for one pitch of the heat transfer tube, the contact area between the medium flowing in the axial direction of the heat transfer body and the heat transfer plate is improved, and the heat transfer efficiency is correspondingly increased. improves.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a partially cutaway sectional view showing an embodiment of the present invention, FIG. 2 is an enlarged view of an essential part of FIG. 1, and the same or corresponding parts as in FIG. 5 and FIG. The description is omitted.

In the figure, (7) is an intermediate heat transfer body made of a thin (for example, 0.1 mm thick) copper plate wound in surface contact with the outer peripheral wall surface of the heat transfer body (1). A heat transfer tube (3) is joined to the outer peripheral wall surface of 7) in a spiral shape using a solder (6) which is a brazing material.

In the heat exchanger configured as above, the wire mesh (1
Since the wire of a) contacts the intermediate heat transfer body (7), and the heat transfer tube (3) easily contacts the intermediate heat transfer body (7),
The contact area between the heat transfer body (1) and the heat transfer tube (3) is increased, and the heat transfer efficiency is improved.

In the above embodiment, the case where the integral intermediate heat transfer plate (7) is used has been described, but as shown in FIG. 3, the intermediate heat transfer plate (7) is divided into a plurality of intermediate heat transfer elements ( When 8) is used, heat that moves along the axial direction of the intermediate heat transfer plate (7) and enters the heat transfer tube (3) is prevented, and the heat exchange efficiency of the heat exchanger is further improved. In addition, as shown in FIG. 4, a thin tape-shaped plate is joined to the heat transfer tube (3) in advance by solder (6), and the intermediate heat transfer plate (7) is wound around the outer peripheral wall surface of the heat transfer body (1). Even if it is formed, the same effect as that of the above embodiment can be obtained. Further, as the heat transfer plate, punch mental may be used instead of the wire mesh (1a). Furthermore, the brazing material may be, for example, a silver brazing material or an aluminum brazing material other than the solder (6). Further, although the low temperature heat exchanger using the first refrigerant (2) and the second refrigerant (4) as the medium has been described, the present invention can be applied to a high temperature heat exchanger using a high temperature medium.

〔The invention's effect〕

As described above, in the heat exchanger of the present invention, the intermediate heat transfer body is interposed between the heat transfer body and the heat transfer tube, so that the contact area between the heat transfer body and the heat transfer tube increases. There is an effect that the heat exchange efficiency is improved.

Further, since the intermediate heat transfer body is formed of a thin material having a high thermal conductivity, the heat transfer cross-sectional area of the heat transfer body of the intermediate heat transfer body in the axial direction is small, and the axial direction of the heat transfer body is reduced accordingly. While the thermal resistance is high, the distance between the heat transfer element and the heat transfer tube is short, which reduces the heat resistance in the radial direction of the heat transfer element, and therefore the heat between the heat transfer element and the heat transfer tube. It also has the effect of further improving the movement efficiency.

Furthermore, since the heat transfer plates are arranged in a plurality of stages for one pitch of the heat transfer tube, the contact area between the medium flowing in the axial direction of the heat transfer body and the heat transfer plate is improved, and the heat transfer efficiency is correspondingly increased. It also has the effect of improving.

[Brief description of drawings]

FIG. 1 is a partially cutaway sectional view showing a low temperature heat exchanger according to an embodiment of the present invention, FIG. 2 is an enlarged view of an essential part of FIG. 1, and FIG. 3 is another embodiment of the present invention. Partially cutaway sectional view,
FIG. 4 is a perspective view of an essential part showing still another embodiment, and FIG. 5 is a partially cutaway sectional view showing an example of a conventional low temperature heat exchanger,
FIG. 6 is an enlarged view of a main part of FIG. (1) ... heat transfer body, (1a) ... wire mesh, (2) ... first refrigerant, (3) ... heat transfer tube, (4) ... second refrigerant,
(6) ... Solder, (7) ... intermediate heat transfer element. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (4)

[Claims] Claim: What is claimed is: 1. A heat transfer body comprising heat transfer plates of high thermal conductivity, and a thin walled body of high heat conductivity provided in surface contact with an outer peripheral wall surface of the heat transfer body. Of the intermediate heat transfer body, and a heat transfer tube made of a material having a high thermal conductivity, which is spirally joined to the outer peripheral wall surface of the intermediate heat transfer body with a brazing filler metal, and the heat transfer tube is connected to one pitch of the heat transfer tube. A heat exchanger in which heat plates are arranged in a plurality of stages and heat is exchanged between a medium flowing in the axial direction of the heat transfer body and a medium flowing in the heat transfer tube. 2. The heat exchanger according to claim 1, wherein the heat transfer plate is a wire mesh made of copper. 3. The heat according to claim 1 or 2, wherein the intermediate heat transfer member is composed of a plurality of intermediate heat transfer elements which are arranged at regular intervals in the axial direction thereof. Exchanger. 4. A brazing filler metal is solder.
The heat exchanger according to any one of items 1 to 3.