JP5927414B2 - Heat exchanger - Google Patents

Description

  The present invention relates to a heat exchanger for exchanging heat between a fluid such as water and two kinds of fluids such as a refrigerant, such as a heat pump type hot water heater, etc., used in equipment such as an air conditioner and a hot water heater. It is.

  Conventionally, this type of heat exchanger is composed of a water pipe that constitutes a water flow path and a refrigerant pipe that constitutes a refrigerant flow path, and is a dual type that exchanges heat between water flowing through the water flow path and refrigerant flowing through the refrigerant flow path. A pipe-type heat exchanger has been devised (see, for example, Patent Document 1).

3 and 4 show a conventional heat exchanger described in Patent Document 1. FIG.
As shown in FIGS. 3 and 4, the heat exchanger 101 is a double-pipe heat exchanger, and is provided outside the refrigerant pipe 103 and a copper refrigerant pipe 103 in which a refrigerant flow path 102 is formed. In this embodiment, two refrigerant pipes 103 are provided. The copper water pipe 105 includes a water flow path 104 formed between the refrigerant pipe 103 and the copper water pipe 105. And the entrance / exit of the copper water pipe 105 consists of the header 106 for copper, and all the materials which comprise the heat exchanger 101 were copper.

  The operation of the heat exchanger configured as described above will be described below.

  The heat exchanger 101 is formed by a double pipe of the refrigerant pipe 103 and the water pipe 105, and exchanges heat between the water and the refrigerant. Therefore, the refrigerant pipe 103 can have a large contact area with water, thereby improving the heat exchange efficiency. it can.

  Since the heat exchanger 101 is a copper double pipe type, the water pipe 105 can be easily bent, and the copper water header 106 and the copper water pipe 105 can be joined by copper brazing. It is known that the structure is easy to manufacture.

JP 2005-69620 A

  However, the conventional heat exchanger is easy to manufacture because it is a copper double tube type, but due to the recent rise in the price of copper bullion, the manufacturing cost due to the raw material cost of the heat exchanger has increased. As a result, there was a problem that the cost of goods increased, and the cost of goods became high, resulting in an increase in the price of goods.

  The present invention solves the above-mentioned conventional problems, while maintaining the quality such as manufacturability and durability reliability of the heat exchanger, by adopting a stainless steel pipe cheaper than the copper material for the water pipe, An object of the present invention is to provide a heat exchanger capable of preventing the risk of soaring raw materials and suppressing an increase in commodity prices.

In order to solve the above-described conventional problems, a heat exchanger according to the present invention includes a water pipe through which water flows, a refrigerant pipe through which refrigerant flows, and the refrigerant pipe disposed in the water pipe. In the heat exchanger that exchanges heat with the refrigerant and uses a part of stainless steel for the water pipe, the water pipe includes a copper pipe connected to a water header, a stainless pipe, the copper pipe, and the stainless pipe. The copper SUS joint is formed such that the end of the stainless steel pipe is disposed inside the diameter-expanded portion of the copper pipe, and the diameter of the copper pipe is increased. The portion and the end of the stainless steel tube are joined by a brazing material .

  With this configuration, a SUS pipe that is less expensive than a copper material is used, so that the risk of rising raw material costs can be prevented and the increase in product prices can be suppressed.

  Moreover, it is comprised from the copper SUS junction part formed by inserting and joining a stainless steel pipe inside the expanded copper pipe.

  With this configuration, even when crevice corrosion occurs on the SUS pipe side of the copper SUS joint and a through hole is opened, water does not leak to the outside of the water pipe, so that no malfunction occurs and normal operation can be maintained.

  Moreover, it is applied to a heat pump type hot water heater using carbon dioxide as a refrigerant.

  With this configuration, when used as a water / refrigerant heat exchanger for a heat pump type hot water heater, the generation of blue water can be reduced because the amount of copper material in contact with water is reduced.

  The heat exchanger of the present invention is a heat exchanger for exchanging heat between water and a refrigerant. Since a stainless material, which is cheaper than the raw material copper material and has a small price fluctuation of the raw material, is used as a part of the water pipe, the raw material price rises. Risks can be reduced and product price increases can be prevented. Furthermore, since it has a copper SUS joint part that is joined by inserting a stainless steel pipe inside the expanded copper pipe, even if the inserted stainless steel pipe has a through hole due to corrosion, water leaks from the heat exchanger. It is possible to provide a heat exchanger that ensures durability and reliability.

External view of the heat exchanger in Embodiment 1 of this invention Cross-sectional view in the axial direction of the copper SUS joint of the heat exchanger in the first embodiment Schematic diagram of conventional heat exchanger Axial sectional view of a double pipe of a heat exchanger showing a conventional example

According to a first aspect of the present invention, there is provided a water pipe through which water flows, a refrigerant pipe through which refrigerant flows, and the refrigerant pipe disposed in the water pipe to exchange heat between the water and the refrigerant, and the water pipe is made of stainless steel. in the heat exchanger using a part of the timber, the water pipe, and copper is connected to the water header pipes, and stainless steel tube, and connected with the copper SUS junction for bonding the stainless steel tube and the copper tube The copper SUS joint is formed such that the end of the stainless steel pipe is disposed inside the enlarged diameter part of the copper pipe, and the enlarged diameter part of the copper pipe and the end of the stainless steel pipe are brazed. It is the heat exchanger characterized by having the structure joined by the material .

  With this configuration, a SUS pipe that is less expensive than a copper material is used, so that the risk of rising raw material costs can be prevented and the increase in product prices can be suppressed.

Moreover, it is comprised from the copper SUS junction part formed by inserting and joining a stainless steel pipe inside the expanded copper pipe.

  With this configuration, even when crevice corrosion occurs on the SUS pipe side of the copper SUS joint and a through hole is opened, water does not leak to the outside of the water pipe, so that no malfunction occurs and normal operation can be maintained.

According to a second invention, in the first invention, the refrigerant is carbon dioxide.

  With this configuration, when used as a water / refrigerant heat exchanger for a heat pump type hot water heater, the generation of blue water can be reduced because the amount of copper material in contact with water is reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is an external view of a heat exchanger according to Embodiment 1 of the present invention. FIG. 2 is an axial cross-sectional view of the copper SUS joint of the heat exchanger according to the first embodiment.

In addition, about the same structure as the conventional heat exchanger 101, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  The heat exchanger 1 is a double-tube heat exchanger in which a water pipe 2 through which water flows, a refrigerant pipe 103 through which refrigerant flows inside, and a refrigerant pipe 103 disposed in the water pipe 2 are disposed. The water pipe 2 is formed by connecting a copper copper pipe 4 connected to a copper water header 106, a stainless steel stainless steel pipe 5, and a copper SUS joint 6 that joins the copper pipe 4 and the stainless steel pipe 5. ing. The copper SUS joint portion 6 is composed of a copper tube expanded portion 7 formed by expanding the copper tube 4 and an end portion of the stainless tube 5. The end portion of the stainless tube 5 is inserted into the copper tube expanded portion 7, It is a structure joined by brazing material 8. The refrigerant is carbon dioxide applied to the heat pump type hot water heater.

  The operation of the heat exchanger configured as described above will be described below.

  The heat exchanger 1 is formed by a double pipe of the refrigerant pipe 103 and the water pipe 2 and exchanges heat between water and the refrigerant.

  Since the water pipe 2 is made of stainless steel, which is cheaper than the raw material copper and has a small price fluctuation of the raw material, as a part of the water pipe 2, the risk of the raw material rising can be suppressed and the commodity price can be prevented from rising.

  When stainless steel pipe 5 is adopted as water pipe 2, direct joining of stainless steel stainless steel pipe 5 and copper water header 106 is difficult to process, requiring more time than necessary, or quality associated with poor joining Loss increases and is not suitable for mass production.

  As a countermeasure against this, by arranging the copper pipe 4 in the middle of the stainless steel pipe 5 and the water header 106, a conventional processing method such as brazing joining can be used for joining the water header 106, and mass productivity is improved. Can be maintained.

  Moreover, since the copper SUS joint part 6 has a structure in which the stainless steel pipe 5 is inserted and joined inside the copper pipe enlarged diameter part 7, corrosion or the like occurs on the stainless steel pipe side of the copper SUS joint part 6 and penetrates. Even if the hole is opened, water does not leak to the outside of the water pipe 2.

  Moreover, since the area of the copper material in contact with water in the water pipe 2 is reduced, there is also an effect that the occurrence risk of “blue water” that occurs very rarely in the heat pump hot water heater can be reduced.

  As described above, the heat exchanger 1 according to Embodiment 1 includes the water pipe 2 in which water flows and the refrigerant pipe in the water pipe to exchange heat between the water and the refrigerant. The copper tube 4 connected to the water header 106, the stainless steel tube 5, and the copper SUS joint 6 that joins the copper tube 4 and the stainless steel tube 5 are provided. The end portion of the stainless tube 5 is formed by inserting the end portion of the stainless tube 5 into the copper tube expanded portion 7, and the copper SUS joint portion 6 joined by the brazing material 8 is provided.

  Therefore, since stainless steel is used that is cheaper and less price-changing than copper, which is a raw material, the risk of rising raw materials can be suppressed, the product price can be prevented from rising, and the inserted stainless steel pipe has a through hole due to corrosion. Even if it is vacant, there is no risk of water leaking from the heat exchanger, and a heat exchanger that ensures durability and reliability can be provided.

  In the first embodiment of the present invention, the number of refrigerant pipes 103 arranged in the water pipe 2 is two, but the same effect can be expected even when the number of the refrigerant pipes is one or more.

Further, in Embodiment 1 of the present invention, the refrigerant circulating in the refrigerant pipe 103 is carbon dioxide. However, the same effect can be obtained by using a hydrocarbon or HFC (such as R410A) refrigerant or an alternative refrigerant thereof. The effect can be expected.

  As described above, the heat exchanger according to the present invention uses a stainless steel as a water pipe to prevent an increase in product price, and solves the problem of the joint between the copper pipe and the stainless pipe. Supercritical heat pump water heater used, supercritical heat pump device for heating brine for heating, air conditioner for home use and business use, washing dryer equipped with drying function by heat pump, grain storage warehouse, etc. In addition to the heat pump device, it can be applied to heat exchange applications such as fuel cells.

DESCRIPTION OF SYMBOLS 1 Heat exchanger 2 Water pipe 103 Refrigerant pipe 106 Water header 4 Copper pipe 5 Stainless steel pipe 6 Copper SUS joint part 7 Copper pipe diameter expansion part

Claims (2)

A water pipe through which water flows, a refrigerant pipe through which refrigerant flows inside, the refrigerant pipe disposed in the water pipe to exchange heat between the water and the refrigerant, and a part of stainless steel was used for the water pipe In the heat exchanger, the water pipe is formed by connecting a copper pipe connected to a water header, a stainless steel pipe, and a copper SUS joint for joining the copper pipe and the stainless steel pipe, and the copper SUS. As for the joining part, the end of the stainless steel pipe is arranged inside the enlarged diameter part of the copper pipe, and the enlarged diameter part of the copper pipe and the end of the stainless steel pipe are joined by a brazing material. A heat exchanger characterized by having a configuration . The heat exchanger according to claim 1, wherein the refrigerant is carbon dioxide and is applied to a heat pump type hot water heater.