JP2006336894A - Heat pump water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve service performance by improving efficiency of a heat exchanging unit by reducing heat loss from a hot water supply heat exchanger to an internal heat exchanger, and preventing fracture of water piping caused by freezing by reducing the quantity of redidual water in draining from the hot water supply heat exchanger. <P>SOLUTION: This heat pump water heater comprises a refrigerating cycle formed by successively connecting a compressor 23, the hot water supply heat exchanger 1, a throttle valve 28 and an evaporator 21, the internal heat exchanger 15 for exchanging the heat between a refrigerant from a refrigerant outlet side of the hot water supply heat exchanger 1 to an inlet side of the throttle valve 18, and a refrigerant from a refrigerant outlet side of the evaporator 21 to a suction side of the compressor 23, and a flow control valve 30 mounted on an internal heat exchanger bypass circuit 29 connecting the refrigerant outlet side of the hot water supply heat exchanger 1 and an outlet side of the throttle valve 28. The hot water supply heat exchanger 1 and the internal heat exchanger 15 are mounted at a lower portion of an air supply chamber and a machine chamber, and the internal heat exchanger 15 is mounted near an outlet of refrigerant piping of the hot water supply heat exchanger 1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat pump water heater provided with a heat exchanger.

  A compressor, four-way valve, water heat exchanger, pressure reducer, and air heat exchanger are connected to a conventional heat pump water heater in order to form a refrigeration cycle, and the water heat exchanger, hot water storage tank, and water circulation pump are sequentially connected. In a heat pump water heater connected to form a water cycle, a water heat exchanger is installed above the compressor, air heat exchanger, and blower in the unit body, and the water heat exchanger is wound in a flat ring shape. There is one in which a water circulation pump formed by a pipe is installed and surrounded by a motor cover inside the pipe (see, for example, Patent Document 1).

Japanese Utility Model Publication No. 59-175945 (page 2-4, FIGS. 1 and 2)

  The heat pump water heater described in Patent Document 1 has a water heat exchanger (internal heat exchanger) installed above the air heat exchanger (heat exchanger for hot water supply). The temperature difference between the temperature of the refrigerant and the temperature of the low-pressure side refrigerant of the internal heat exchanger (3 to 10 deg lower than the outside air temperature) is very large. Therefore, heat exchange from the hot water supply heat exchanger to the internal heat exchanger appear. This means that heat for heating the water is lost. In particular, the loss of heat from the high-pressure and high-temperature refrigerant for heating water to a high temperature has a problem of significantly reducing the efficiency of the heat exchange unit.

In addition, when the heat pump water heater is not used for a long time in winter, drain water to prevent the pipe from being damaged due to water freezing, but the hot water heat exchanger is located at the bottom of the heat exchange unit. However, there is also a problem that water is not easily drained and the water piping of the heat exchanger for hot water supply is easily damaged by the remaining water.
In addition, since the internal heat exchanger is located at the top of the blower room and machine room, these services cannot be performed simply by opening the top panel during services such as replacing electrical components, fan motors, or thermistors. There was a problem with serviceability.

  The present invention has been made to solve the above-described problems, and improves the efficiency of the heat exchanger unit by reducing the heat loss from the hot water supply heat exchanger to the internal heat exchanger, and the hot water supply heat. It is an object of the present invention to provide a heat pump water heater that can reduce the amount of residual water when draining water from an exchanger, prevent water piping from being broken due to freezing, and improve serviceability.

  The heat pump water heater according to the present invention includes a refrigeration cycle in which a compressor, a heat exchanger for hot water supply, a throttle valve, and an evaporator are sequentially connected, and a refrigerant outlet side of the hot water supply heat exchanger to an inlet side of the throttle valve. An internal heat exchanger for exchanging heat between the refrigerant and the refrigerant from the refrigerant outlet side of the evaporator to the suction side of the compressor, and an interior connecting the refrigerant outlet side of the hot water supply heat exchanger and the outlet side of the throttle valve A flow control valve provided in a heat exchanger bypass circuit, and the heat exchanger for hot water supply and the internal heat exchanger are installed in the lower part of the blower chamber and the machine room, and the internal heat exchanger is heated for hot water supply It is arranged near the outlet of the refrigerant pipe of the exchanger.

  In the heat pump water heater according to the present invention, the internal heat exchanger is disposed adjacent to the lower part, which is the bottom temperature of the hot water heat exchanger, so that the temperature difference between the hot water heat exchanger and the internal heat exchanger is reduced. Therefore, heat loss due to heat transfer from the hot water supply heat exchanger to the internal heat exchanger can be reduced, and at the same time, serviceability can be improved. In addition, since the hot water supply heat exchanger is arranged on the internal heat exchanger, there is a difference in height between the water drain plug and the hot water supply heat exchanger, so there is little residual water when draining water. it can. Furthermore, since it is not necessary to place an internal heat exchanger in the machine room, it is possible to secure space occupied by other pipes in the machine room, facilitating structural design, and preventing abnormal noise from being caused between pipes. Therefore, the tolerance of the vibration stress of the pipe is increased and the reliability can be improved.

[Embodiment 1]
1 is an exploded perspective view of a hot water supply outdoor unit equipped with a hot water supply heat exchanger according to Embodiment 1 of the present invention, and FIG. 2 is a piping system diagram of the refrigeration cycle circuit and hot water supply circuit of FIG.
A hot water supply heat exchanger unit 11 is arranged at the lowermost stage of the hot water supply outdoor unit in FIG. 1, and a blower 22 for sending wind to exchange heat between the evaporator 21 and the outside air is arranged on the left side of the upper part. An air blowing chamber is provided. A compressor 23 is installed adjacent to the blower 22 on the right side of the upper part of the hot water supply heat exchanger unit 11, and a machine room in which a pump 24 for circulating water in the hot water supply circuit is arranged on the right side. Water from a hot water supply tank (not shown) is taken into the indoor unit via a water inlet valve 25, passed through the water pipe 2 of the hot water supply heat exchanger 1 provided in the hot water supply heat exchanger unit 11, and supplied with hot water. The outlet valve 31 returns to the hot water supply tank.
The outer shell includes a grille 19 on the front, a front panel 18 having an air inlet on the left side, a back panel 20 that covers from the right side to the end of the evaporator 21, and a service panel 26 that covers valves. A top panel 27 is disposed at the top.

  In FIG. 2, a compressor 23, a hot water supply heat exchanger 1, a throttle valve 28, and an evaporator 21 are sequentially connected to form a refrigeration cycle, and the throttle valve from the refrigerant outlet side of the hot water supply heat exchanger 1. An internal heat exchanger 15 for exchanging heat between the refrigerant up to the refrigerant inlet side 28 and the refrigerant outlet side of the evaporator 21 and the refrigerant up to the suction side of the compressor 23 is provided. A flow rate adjustment valve 31 is provided in the internal heat exchanger bypass circuit 29 provided between the refrigerant outlet side of the hot water supply heat exchanger 1 and the refrigerant outlet side of the throttle valve 28.

In the hot water supply equipment configured as described above, the heated gas refrigerant that has become high temperature and high pressure by the compressor 23 flows into the refrigerant pipe 5 of the hot water supply heat exchanger 1 and is taken in from the water inlet valve 25 by the pump 24. When the water in the hot water supply tank passes through the water pipe 2 of the hot water supply heat exchanger 1, heat is exchanged to heat the water, and the water returns to the hot water supply tank via the hot water supply outlet valve 31.
In addition, the refrigerant that has transferred heat to the water is decompressed by the throttle valve 28 and flows into the evaporator 21, absorbs heat from the outside air blown by the blower 22, is evaporated and is reheated by the internal heat exchanger 15. The process returns to the compressor 23. The flow rate of the high-pressure refrigerant flowing into the internal heat exchanger 15 is adjusted by the flow rate adjustment valve 30.

3 is a perspective view showing an assembled state of the above-described hot water supply heat exchanger unit, FIG. 4 is an explanatory diagram of the hot water supply heat exchanger of FIG. 3, and FIG. 5 is a water pipe constituting the hot water supply heat exchanger. Indicates a state in which 2a is turned upside down.
As shown in FIG. 6, the water pipe 2 has a plurality of (for example, 2 to 4) crests 3 a and troughs 3 b alternately provided on the outer periphery, and the crests 3 are continuously provided for each of the crests. Provided in a spiral shape, smooth parts (connecting parts) having no peaks and valleys 3 are formed at both ends, and the end of one smooth part is expanded into a bag shape and the smooth part of the subsequent water pipe 2 is inserted. Has been able to connect continuously.

  In FIG. 4 again, the high-pressure refrigerant inlet portion 7 is branched into a plurality of refrigerant pipes 5 through the connecting portions 6a, and is fitted into the valley portions 3b of the mountain valley portions 3 provided on the outer periphery of the water pipe 2. Wound over the entire length. Then, the water pipe 2 around which the refrigerant pipe 5 is wound is bent and connected in an oval spiral shape as shown in FIG. Connected to. In addition, 4 is a connection part of the some water piping 2, and is located in the ellipse spiral-shaped linear part. In the hot water supply heat exchanger 1, the water flowing through the water supply pipe 2 and the refrigerant flowing through the refrigerant pipe 5 are configured to face each other.

  FIG. 7 is a plan view and a side view of the internal heat exchanger 15. The internal heat exchanger 15 has a double-pipe structure. A high-pressure refrigerant flows through the inner pipe, which is the high-pressure refrigerant pipe 16, and the low-pressure refrigerant pipe. A low-pressure refrigerant flows through the outer pipe 17. 16a is a high-pressure refrigerant inlet, 16b is an outlet, 17a is a low-pressure refrigerant inlet, and 17b is an outlet. The low-pressure refrigerant may flow through the high-pressure refrigerant pipe (inner pipe) 16 and the high-pressure refrigerant may flow through the low-pressure refrigerant pipe (outer pipe) 17.

FIG. 8 is an explanatory view showing the arrangement of the hot water supply heat exchanger 1 and the internal heat exchanger 15.
An internal heat exchanger 15 is disposed below the hot water supply heat exchanger 1 via a heat insulating material 13, and the high-temperature and high-pressure refrigerant discharged from the compressor 23 is disposed at the upper part of the hot water supply heat exchanger 1. The water flowing in from the high-pressure refrigerant inlet 7 and heating the water flowing in the water pipe 2 to flow out from the lower high-pressure refrigerant outlet 8, then flows into the high-pressure refrigerant pipe 16 of the internal heat exchanger 15 from the high-pressure refrigerant inlet 16 a. Then, after exchanging heat with the low-pressure refrigerant in the low-pressure refrigerant pipe 17, it flows out from the high-pressure refrigerant outlet 16b.

  On the other hand, the low-pressure refrigerant that has flowed out of the evaporator 21 flows into the low-pressure refrigerant pipe 17 from the low-pressure refrigerant inlet portion 17a, recovers heat from the high-pressure refrigerant flowing through the high-pressure refrigerant pipe 16, and then flows out of the low-pressure refrigerant outlet portion 17b. 23 is inhaled. The water flowing through the water pipe 2 flows in from the water pipe inflow part 2c, is heated by the high-temperature and high-pressure refrigerant flowing through the refrigerant pipe 5, and then flows out from the water pipe outflow part 2d. In addition, 12 is a drain plug, is provided in the lowest part of the heat exchanger unit 11 for hot water supply, and is connected with the lower part of the heat exchanger 1 for hot water supply by piping.

  FIG. 9 is a diagram showing the relationship between the channel length and temperature of the hot water supply heat exchanger 1 and the internal heat exchanger 15 when carbon dioxide is used as the refrigerant. The upper part of the figure shows the temperature in the hot water supply heat exchanger 1, and the lower left part shows the temperature in the internal heat exchanger 15. The flow direction of the refrigerant in the supercritical state at high temperature and pressure is from right to left, as shown by the solid line, the temperature rapidly decreases after inflow, and then gradually decreases through a pinch point. Although the temperature at the time of inflow depends on environmental conditions, it is 80 to 150 ° C., and the rapid decrease in temperature after inflow is due to the physical property value (specific heat, etc.) of the refrigerant.

On the other hand, since water flows counter to the refrigerant, the flow direction is left to right and gradually heated with respect to the flow direction as indicated by a broken line. The maximum heating temperature of water is about 90 ° C.
The high-pressure refrigerant flows out of the hot water supply heat exchanger 1 and then flows into the internal heat exchanger 15 at the lower left of the figure from the right end to exchange heat with the low-pressure refrigerant. Since the low-pressure refrigerant is opposed to the flow direction of the high-pressure refrigerant, the flow direction is left to right and gradually heated with respect to the flow direction as indicated by a one-dot chain line.

  In the present embodiment, since the internal heat exchanger 15 is disposed at the position (lower side) where the refrigerant and water in the hot water supply heat exchanger 1 are at the lowest temperature (lower side), the low-pressure side refrigerant temperature (outside temperature) of the internal heat exchanger 15 The temperature difference between the heat exchanger 1 for hot water supply 1 and the internal heat exchanger 15 is minimized. Thereby, heat can be exchanged in order to heat water without wasting the heat energy of the refrigerant. In particular, since there is no heat loss from the high-temperature refrigerant when heating water to a high temperature, the boiling efficiency of the hot water supply heat exchanger unit 11 can be improved.

  In addition, when the heat pump water heater is not used for a long time in winter, water is drained to prevent the pipe from being destroyed due to water freezing, but the hot water heat exchanger 1 is disposed on the internal heat exchanger 15. Therefore, since a height difference is obtained between the drain plug 12 and the hot water supply heat exchanger 1, residual water can be reduced during draining. For this reason, it is possible to prevent the pipe from being broken due to freezing of the remaining water, and to improve the reliability.

  Furthermore, since the internal heat exchanger 15 does not have to be arranged in the machine room, the space occupied by other pipes in the machine room can be secured, so that the structure design of the pipes becomes easy and abnormal noise is generated due to contact between the pipes. Can be prevented, and the vibrational stress of the pipe can be increased to improve the reliability.

[Embodiment 2]
FIG. 10 is an explanatory view of a hot water supply heat exchanger according to Embodiment 2 of the present invention, and FIG. 11 is an explanatory view of the internal heat exchanger. The same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
As in the case of the first embodiment, the hot water supply heat exchanger 1 is fitted with the refrigerant pipes 5 in the valley portions 3b of the plurality of mountain valley portions 3 continuously provided in a spiral manner on the outer periphery of the water pipe 2, respectively. And is formed by bending into an elliptical coil shape. In addition, the connection part 4 of the water piping 2 is located in the ellipse coil-like linear part, and it is comprised so that a refrigerant | coolant and water may become a counterflow.
Further, the internal heat exchanger 15 is obtained by bending a high-pressure refrigerant pipe 16 around the outer periphery of the low-pressure refrigerant pipe 17 in a spiral manner. In addition, as in the case of the water pipe 2, a crest / valley part may be provided on the outer periphery of the low-pressure refrigerant pipe 17, and the high-pressure refrigerant pipe 16 may be wound along the trough part.

FIG. 12 is an explanatory view showing the arrangement of the hot water supply heat exchanger 1 and the internal heat exchanger 15. The internal heat exchanger 15 is arranged on the lower side of the hot water supply heat exchanger 1. In this case, it is desirable that the height of the internal heat exchanger 15 is not more than half of the height of the hot water supply heat exchanger 1.
The high-temperature and high-pressure refrigerant discharged from the compressor 23 flows in from the high-pressure refrigerant inlet 7 at the upper part of the hot water supply heat exchanger 1 to heat the water in the water pipe 2 and flows out from the lower high-pressure refrigerant outlet 8. After that, the refrigerant flows into the high-pressure refrigerant pipe 16 of the internal heat exchanger 15, exchanges heat with the low-pressure refrigerant in the low-pressure refrigerant pipe 17, and flows out from the high-pressure refrigerant outlet portion 8.

On the other hand, the low-pressure refrigerant flowing out of the evaporator 21 flows into the low-pressure refrigerant pipe 17 from the low-pressure refrigerant inlet part 17a, recovers heat from the high-pressure refrigerant flowing through the high-pressure refrigerant pipe 16, and then flows out from the low-pressure pipe outlet part 17b. 23 is inhaled. Further, water flows into the water pipe 2 from the lower water pipe inflow part 2c of the hot water supply heat exchanger 1, is heated by the high-pressure high-temperature refrigerant flowing through the refrigerant pipe 5, and flows out from the upper water pipe outflow part 2d. The drain plug 12 is connected to the lower portion of the hot water supply heat exchanger unit 11 by piping. The relationship between the channel length and the temperature of the hot water supply heat exchanger 1 and the internal heat exchanger 15 according to the present embodiment is the same as in the case of FIG.
The effect of this embodiment is the same as that of the first embodiment.

[Embodiment 3]
FIG. 13 is a cross-sectional view of a main part of a heat exchanger for hot water supply according to Embodiment 3 of the present invention, and FIG. 14 is a partially enlarged view of FIG. The same parts as those in the first embodiment are denoted by the same reference numerals.
In this embodiment, the water pipe 2 provided with a plurality of ridges and valleys 3 provided on the outer periphery (three cases are shown in the figure) continuously spirally for each row is provided with three passes. The refrigerant pipes 5a, 5b, 5c are spirally wound along the valleys 3b of the respective strips to enlarge the contact area between the water pipe 2 and the refrigerant pipes 5a, 5b, 5c. In the present embodiment, the valley portion 3b of the mountain valley portion 3 is formed in a substantially inverted trapezoidal shape.

Then, with respect to the flow direction of water in the water pipe 2 (indicated by arrows), the refrigerant branched at the inlet flows in the opposite direction so as to be spirally opposed in the refrigerant pipes 5a, 5b, 5c, It merges again at the exit and becomes one. In this case, CO ₂ , HFC, HCFC, HC, H ₂ O, or the like can be used as the refrigerant, but the refrigerant is not limited to this.

In FIG. 14, the height H of the crest 3 a of the crest portion 3 provided on the outer periphery of the water pipe 2 is set to be not less than the radius R _o / 2 and not more than the diameter R _o of the refrigerant pipe 5. That is, the height of the crest 3a is made larger than the radius R _o / 2 of the refrigerant pipe 5 in order to stably secure the contact area between the crest 3c of the valley 3b and the refrigerant pipe 5. . Further, the spiral pitch P of the crest 3a is equal to or less than 2 times the diameter R _o at least the diameter R _o of the refrigerant pipe 5.

  As described above, the refrigerant pipe 5 is wound around the outer periphery of the water pipe 2 at the pitch P in the specific range and at the height H of the peak part 3a in the specific range, so that the mountain valley part 3 serves as a guide. Thus, the refrigerant pipe 5 can be easily wound and fixed at a predetermined position, and excessive flattening and buckling of the refrigerant pipe 5 can be prevented.

Furthermore, the width B of the bottom 3d of the valley portion 3b of the peaks and valleys portion 3, at least the inside diameter R _i of the refrigerant pipe 5, and the following outer diameter R _o + 0.24 mm. Thus, by setting the width B of the valley portion 3b to be equal to or larger than the inner diameter R _i of the refrigerant pipe 5 by inserting an inner diameter mandrel or the like, the refrigerant pipe 5 is reliably in contact with the bottom 3d of the valley portion 3b and the refrigerant pipe 5 Since the pressing force to the bottom 3d is easily generated by the tension at the time of winding, the contact thermal resistance can be reduced.

In this embodiment, the height H of the ridges 3a of the peaks and valleys portion 3 provided on the outer circumference of the water pipe 2 is too high than a diameter R _o of the refrigerant pipe 5, space efficiency of the heat exchanger is deteriorated converting mechanism prevents the compact, the pitch P of the crest 3a can not be fitted the refrigerant pipe 5 that it follows the diameter R _o of the refrigerant pipe 5 deep valleys 3b, Thus, the refrigerant pipe 5 is valley Since the bottom 3d of 3b cannot be contacted, the contact heat transfer area between the refrigerant pipe 5 and the water pipe 2 is reduced, and the original purpose cannot be achieved. In addition, if the pitch P of the crest 3a is too large and exceeds twice the diameter _Ro of the refrigerant pipe 5, the total length of the refrigerant pipe 5 per unit length of the water pipe 2 becomes short. The performance as a vessel is lowered, which is not preferable.

Further, in the present embodiment, even when the contact area between the valley 3b of the water pipe 2 and the refrigerant pipe 5 is enlarged by brazing or the like, the gap between the mountain side inclined surface 3c of the valley 3b and the refrigerant pipe 5 is increased. A brazing gap can be designed. In general, in order to ensure brazing quality, it is desirable from the viewpoint of work that the brazing gap is 0.08 mm to 0.12 mm. For this reason, the gap between the refrigerant pipe 5 and the ridge side inclined surface 3c is formed on both sides. 0.16mm~0.24mm Tosureba well, thus, the width B of the bottom 3d of the valley 3b is preferred if the diameter R _o + 0.16~0.24mm the refrigerant pipe 5. Thereby, the contact area of the trough part 3b and the refrigerant | coolant piping 5 can be expanded with few brazing materials.

Further, as shown in FIG. 13, the mountain valley portion 3 provided on the outer periphery of the water pipe 2 has a shape in which turbulent flow is likely to occur inside the water pipe 2. Can be improved.
Furthermore, since the peak part 3a of the peak part 3 provided in the water piping 2 acts also as a heat exchange fin, thermal conductivity improves by the fin efficiency improvement effect.

  According to the present embodiment, the refrigerant pipe 5 is in contact with the bottom 3d of the valley 3b provided on the outer periphery of the water pipe 1, and the minimum gap portion between the mountain side inclined surface 3c of the valley 3b and the refrigerant pipe 5 is used. However, since contact is made directly or by brazing or the like, there are three contact portions and heat transfer is joined. As a result, the effective contact heat transfer area can be increased by more than three times compared to a conventional hot water supply heat exchanger in which a refrigerant pipe is wrapped around a smooth water pipe. Since the efficiency improvement also acts as a synergistic effect, the AK value (heat transfer area × heat passage rate) per unit water pipe length can be greatly improved.

Here, the water pipe 2 was manufactured by fixing both ends of the phosphorous deoxidized copper smooth pipe, inserting a mandrel on the inner diameter side, and adding a twisting process, but the invention is not limited to this. The water pipe 2 may be manufactured by other pipe processing techniques such as processing, cast forging, cutting, and rolling. Moreover, if the raw material of the water pipe 2 is an internally grooved pipe, a suitable effect can be obtained.
Further, the material of the water pipe 2 and the refrigerant pipe 5 is not limited to phosphorous deoxidized copper, and pipe metals such as copper, aluminum, iron, stainless steel, titanium, or alloys thereof are used depending on the application. May be.
Examples of the present embodiment will be described below.

The water pipe 2 has an outer diameter SR _o : 14.0 mm, an inner diameter SR _i : 8.0 mm, a number of ridges: 4, a height H of the mountain part 3a: 2.5 mm, and a mountain part 3a. Pitch P: 4.8 mm, bottom portion 3d width B: 3.0 mm, refrigerant pipe 5 has outer diameter R _o : 3.2 mm, inner diameter R _i : 2.0 mm, and refrigerant has four passes And there is no brazing.
In this embodiment, by setting the dimensional relationship between the crest and valley portion 3 of the water pipe 2 and the refrigerant pipe 5 to be indented, a relatively excellent heat transfer performance is exhibited without brazing between them. did it.

The water pipe 2 has an outer diameter SR _o : 14.0 mm, an inner diameter SR _i : 8.0 mm, the number of ridges: 3, the height H of the ridge 3a: 3.0 mm, the pitch P of the ridge 3a: 5.8 mm, Width B of the bottom portion 3d of the valley portion 3b: 3.5 mm, the refrigerant pipe 5 has an outer diameter R _o : 3.6 mm, an inner diameter R _i : 2.4 mm, the refrigerant has three passes, and a phosphor copper of φ0.8 Was spirally wound and brazed.

  In this example, heat transfer performance was further improved because heat transfer bonding was performed by brazing the heat transfer contact portion. In brazing, as shown in FIG. 15A, the gap between the crest 3a of the water pipe 2 and the refrigerant pipe 5, or as shown in FIG. 15B, the bottom of the trough 3b of the water pipe 2. A brazing material 9 or solder material or the like may be wound around the gap between 3d and the refrigerant pipe 5, and further, as shown in FIG. 16, the bottom 3d of the valley 3b of the water pipe 2 and the refrigerant pipe 5 In the meantime, a ribbon-like brazing material 9 or a solder material can be appropriately wound.

Water pipe 2 has an outer diameter SR _o: 15.0 mm, inner diameter SR _i: 9.0 mm, Conditions: 2, crest 3a height H: 3.5 mm, crest 3a of the pitch P: 6.2 mm, The width B of the bottom portion 3d of the valley portion 3b is 4.0 mm, the refrigerant pipe 5 has an outer diameter R _o : 4.0 mm, an inner diameter R _i : 2.8 mm, the refrigerant has two passes, and a width: 3.5 mm. A ribbon-shaped solder material 9 having a thickness of 0.2 mm was set and soldered as shown in FIG.

Water pipe 2 has an outer diameter SR _o: 18.0 mm, inner diameter SR _i: 10.0 mm, Conditions: 4, crest 3a height H: 3.5 mm, crest 3a of the pitch P: 7.2 mm, As shown in FIG. 16, the width B of the bottom 3d of the valley portion 3b is 5.0 mm, the refrigerant pipe 5 has an outer diameter R _{o of} 5.0 mm, an inner diameter R _{i of} 4.0 mm, and the refrigerant has two passes. The ribbon-shaped low melting point metal 9 such as aluminum, solder, brazing material or the like is wound between and joined to the bottom 3 d of the valley 3 b of the water pipe 2 and the refrigerant pipe 5.

In Example 4, since the low melting point metal 9 having high plastic deformation ability such as aluminum, solder, brazing material, etc. is sandwiched between the bottom 3d of the valley 3b of the water pipe 2 and the refrigerant pipe 5, When the pressure is sufficient, an excellent heat transfer bonding can be realized without performing heat brazing as in the case of the first embodiment. Although not shown in the examples, according to the experimental results, the outer diameter SR _o of the crest 3 a of the crest 3 of the water pipe 2 is 1.5 times or more and 2.5 times or less than the inner diameter SR _i. In addition, the inner diameter SR _i of the water pipe 2 is preferably 8 mm or more and 12 mm or less.

  FIG. 17 is an explanatory view showing a state in which the refrigerant pipe 5 is heated and brazed to the valley 3 b of the water pipe 2. Heat brazing can be performed by in-furnace brazing, high-frequency brazing, gas burner brazing, or the like. The same applies to soldering.

  According to the present embodiment, by appropriately setting the dimensions of the mountain valley portion 3 provided on the outer periphery of the water pipe 2 and the refrigerant pipe 5 wound around this, without brazing between them or both By interposing a low-melting-point metal with high plastic deformation ability such as aluminum, solder, brazing material in between, heat brazing is performed, or both are integrally joined by pressure, so heat transfer joining is performed. In particular, the productivity and quality can be improved remarkably, and excellent heat transfer performance can be exhibited. Needless to say, this embodiment can be applied to the first and second embodiments.

[Embodiment 4]
FIG. 18 is an explanatory diagram showing an example of the number of ridges and valleys provided on the outer periphery of the water pipe according to Embodiment 4 of the present invention and the path pattern of the refrigerant pipe wound around this.
FIG. 18A shows an example in which the mountain valley portion 3 has two lines and the refrigerant pipe 5 has two passes, and FIG. 18B shows an example in which the mountain valley portion 3 has three lines and the refrigerant pipe 5 has three passes. ) Is an example in which the mountain valley portion 3 has three lines and the refrigerant pipe 5 has two passes, FIG. 18D shows an example in which the mountain valley portion 3 has four lines and the refrigerant pipe 5 has four passes, and FIG. 4 and an example in which the refrigerant pipe 5 has two passes is shown. As described above, the refrigerant pipes 5 branched into these 2 to 4 paths are integrated at the inlet and the outlet, and become one each.
The number of ridges and valleys 3 of the water pipe 2 and the number of passes of the refrigerant pipe 5 wound around the water pipe 2 can be suitably selected according to characteristics such as the flow rate, flow velocity, and pressure loss of the refrigerant.

  The heat exchanger for hot water supply according to the present invention described above is not limited to a heat exchanger for a heat pump type hot water heater, and can be widely applied to heat exchangers related to water and refrigerant. In addition, the heat exchanger which concerns on this invention can further improve heat exchange performance by winding a heat insulation tape around an outer periphery, or covering with a heat insulating material.

It is a disassembled perspective view of the hot water supply outdoor unit provided with the heat exchanger for hot water supply which concerns on Embodiment 1 of this invention. FIG. 2 is a piping system diagram of the refrigeration cycle circuit and hot water supply circuit of FIG. 1. It is a perspective view which shows the structure of the heat exchanger unit for hot water supply of FIG. It is explanatory drawing of the heat exchanger for hot water supply of FIG. It is explanatory drawing of the water piping which comprises the heat exchanger for hot water supply of FIG. It is an enlarged view of the water piping of FIG. It is the top view and side view of an internal heat exchanger of FIG. It is explanatory drawing which shows arrangement | positioning of the heat exchanger for hot water supply, and an internal heat exchanger. It is a diagram which shows the relationship between the flow path length and temperature of the heat exchanger for hot water supply, and an internal heat exchanger. It is explanatory drawing of the heat exchanger for hot water supply which concerns on Embodiment 2 of this invention. It is explanatory drawing of the internal heat exchanger which concerns on Embodiment 2. FIG. It is explanatory drawing which shows arrangement | positioning of the heat exchanger for hot water supply of Embodiment 2, and an internal heat exchanger. It is principal part sectional drawing of the heat exchanger which concerns on Embodiment 3 of this invention. FIG. 14 is a partially enlarged view of FIG. 13. FIG. 6 is an explanatory diagram of Example 2. It is explanatory drawing of Example 4. FIG. It is explanatory drawing which shows the state which joined the trough part of water piping, and refrigerant | coolant piping by heating brazing. It is explanatory drawing which shows the example of the path | route pattern of the refrigerant | coolant piping wound around this with the number of the threads of the water piping which concerns on Embodiment 4 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heat exchanger for hot water supply, 2 water piping, 3 mountain valley part, 3a mountain part, 3b valley part, 3c mountain part side inclined surface, 3d bottom part, 4 connection part, 5 refrigerant piping, 15 internal heat exchanger, 16 high pressure refrigerant | coolant Piping, 17 Low pressure refrigerant piping.

Claims (15)

A refrigeration cycle in which a compressor, a hot water supply heat exchanger, a throttle valve, and an evaporator are sequentially connected, a refrigerant from a refrigerant outlet side of the hot water heat exchanger to an inlet side of the throttle valve, and a refrigerant outlet side of the evaporator An internal heat exchanger that exchanges heat from the refrigerant to the compressor suction side, and an internal heat exchanger bypass circuit that connects the refrigerant outlet side of the hot water heat exchanger and the outlet side of the throttle valve A flow control valve,
The hot water supply heat exchanger and the internal heat exchanger are installed below the blower chamber and the machine room, and the internal heat exchanger is disposed in the vicinity of the outlet of the refrigerant pipe of the hot water supply heat exchanger. Heat pump water heater.   The heat pump water heater according to claim 1, wherein the internal heat exchanger is disposed below the hot water heat exchanger.   The heat pump water heater according to claim 1, wherein the internal heat exchanger is disposed at a side of the heat exchanger for hot water supply at a height equal to or less than a half of the heat exchanger for hot water supply.   The heat exchanger for hot water supply includes a water pipe in which a plurality of valleys and valleys are continuously provided spirally on the outer circumference, and a refrigerant pipe that is spirally wound along the valleys of the water pipe. The heat pump water heater according to any one of claims 1 to 3, wherein the refrigerant pipe is fitted and wound around a valley of a valley of a water pipe.   The heat pump water heater according to claim 4, wherein a plurality of refrigerant pipes are wound around the heat exchange water pipe.   The heat pump water heater according to claim 4 or 5, wherein water flowing through the heat exchange water pipe and a refrigerant flowing through the refrigerant pipe are opposed to each other.   The heat pump water heater according to any one of claims 4 to 6, wherein an outer diameter of a crest portion of a mountain valley portion of the water pipe is set to be 1.5 times or more and 2.5 times or less of an inner diameter thereof.   The heat pump water heater according to any one of claims 4 to 7, wherein a height of a crest portion of a crest and trough portion of the water pipe is formed to be not less than 1/2 of the outer diameter of the refrigerant pipe and not more than the outer diameter. .   The heat pump water heater according to any one of claims 4 to 8, wherein the pitch of the crests of the crests and valleys of the water pipe is formed to be not less than the outer diameter of the refrigerant pipe and not more than twice the outer diameter.   The width of the bottom part of the valley part of the peak part of the said water piping was formed in the outer diameter + 0.16mm-0.24mm or less more than the internal diameter of refrigerant | coolant piping, The any one of Claims 4-9 characterized by the above-mentioned. Heat pump water heater.   The heat pump water heater according to any one of claims 4 to 10, wherein a minimum gap portion formed between a mountain-side inclined surface of a mountain-valley portion of the water pipe and the refrigerant pipe is heat-transferred.   The heat pump water heater according to any one of claims 4 to 11, wherein a mountain valley portion of the water pipe and a refrigerant pipe wound around the water pipe are joined by a low melting point metal.   The heat pump water heater according to any one of claims 4 to 12, wherein a thickness of the water pipe is 0.5 mm or more and 1.0 mm or less.   14. The heat pump water heater according to claim 4, wherein an inner diameter of the water pipe is 8 mm or more and 12 mm or less. The heat pump water heater according to claim 1, wherein the refrigerant flowing through the refrigerant pipe is a carbon dioxide refrigerant.

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