JP5525278B2 - Heat source unit - Google Patents

Description

  The present invention relates to a heat source unit, and more particularly to a heat source unit having an improved refrigerant flow.

  Conventionally, a refrigeration cycle of a multi-type air conditioner to which a plurality of indoor units are connected is provided with a plurality of electronic expansion valves connected in parallel to each other, and flows through the refrigeration cycle by changing the opening of these electronic expansion valves. The refrigerant flow rate is controlled. Thereby, fine flow control is performed (for example, refer to patent documents 1).

JP 2003-214729 A

  In the refrigeration cycle described in Patent Document 1, when a plurality of heat exchangers are connected and divided, the refrigerant flow is biased in the branch pipe due to the difference in opening of the plurality of expansion valves, and the plurality of heat exchangers are uniform. In this case, there is a problem that a heat exchanger does not flow and a heat exchanger that does not sufficiently exchange heat occurs.

  The present invention has been made in consideration of the above-described circumstances, and a refrigeration cycle in which refrigerant flows uniformly in a plurality of heat exchangers without causing a bias in the refrigerant flow in the branch pipe due to a difference in opening degree of the plurality of expansion valves. It aims at providing the heat source unit provided with.

  In order to achieve the above-described object, a heat source unit according to the present invention is a heat source unit in which a compressor, a plurality of heat exchangers, and a plurality of expansion valves are connected by refrigerant piping, and the plurality of expansion valves. An expansion valve connecting pipe connected in parallel in a substantially vertical direction and arranged substantially horizontally, a cross pipe connected to the expansion valve connecting pipe via a first connection port, and the first A collision tube connected to the second connection port on the opposite side of the connection port, and a third connection port and a fourth connection port of the cross tube in a horizontal state, and a refrigerant is connected to the plurality of heat exchangers. And a branch pipe that divides the flow.

  According to the heat source unit according to the present invention, the refrigerant flows uniformly in the plurality of heat exchangers and can exhibit its ability without causing a bias in the refrigerant flow in the branch pipe due to the difference in opening of the plurality of expansion valves. Can be provided.

The system diagram of the heat pump refrigerating cycle used for 1st Embodiment of the heat-source unit which concerns on this invention. The perspective view of the cross pipe vicinity used for 1st Embodiment of the heat-source unit which concerns on this invention. The perspective view of the cross pipe vicinity used for 2nd Embodiment of the heat-source unit which concerns on this invention.

  A first embodiment of a heat source unit according to the present invention will be described with reference to the accompanying drawings, taking a multi-type air conditioner as an example.

  As shown in FIG. 1, an air conditioner 1 includes an outdoor unit 2 that is a heat source unit of the first embodiment and a plurality of indoor units 3 that are use-side units, a gas-side refrigerant pipe P1 and a liquid-side refrigerant. A refrigerant pipe P composed of the pipe P2 is connected locally.

  The outdoor unit 2 includes a compressor 21 that compresses the refrigerant, a four-way valve 22 that switches the flow of the refrigerant in the air conditioning operation, a plurality of outdoor heat exchangers 23 (23a and 23b) that are heat source side heat exchangers, and a refrigerant branch Cross pipe 24, expansion valve connection pipe 25, electronic expansion valves 26 (26a, 26b) as a plurality of outdoor expansion valves, and liquid tank 27 are connected by refrigerant pipe P3, and further, compressor 21 and four-way valve 22 are connected. An accumulator 28 is provided between them, and an outdoor fan 29 is provided in the outdoor unit 2.

  The indoor unit 3 includes an indoor side heat exchanger 31 that is a respective use side heat exchanger, an indoor side electronic expansion valve 32, and an indoor side blower 33.

The outdoor heat exchanger 23 includes a plurality of, for example, two heat exchangers 23a and 23b, each of which includes a plurality of refrigerant tubes and a plurality of fins that form a plurality of refrigerant flow paths.
During the cooling operation in which the outdoor heat exchanger 23 acts as a condenser (indicated by solid arrows in FIG. 1), the refrigerant is divided into a plurality of refrigerant flow paths of the heat exchangers 23a and 23b on the refrigerant inlet side. A header 41 to be connected is connected. During the heating operation (indicated by dotted arrows), the header 41 is on the refrigerant outlet side, and merges the refrigerants in the plurality of refrigerant channels.

  On the other hand, distributors 42a and 42b for dividing the refrigerant into a plurality of refrigerant flow paths are connected to the refrigerant inlet side when the outdoor heat exchanger 23 acts as an evaporator. During the cooling operation, when the outdoor heat exchanger 23 acts as a condenser, the distributors 42a and 42b are on the refrigerant outlet side, and the refrigerants in the plurality of refrigerant channels are merged.

  As shown in FIGS. 1 and 2, the inflow pipes (horizontal pipes) 262a and 262b are connected to the valve bodies 261a and 261b arranged in the substantially vertical direction of the two outdoor electronic expansion valves 26a and 26b. Here, for convenience, during heating operation, a pipe that allows refrigerant to flow into the electronic expansion valve is referred to as an inflow pipe, and a pipe that flows out is referred to as an outflow pipe.

The inflow pipes 262 a and 262 b are substantially L-shaped and are erected in parallel with each other, and one end of the inflow pipes 262 a and 262 b is connected to the branch portion P3 a of the refrigerant pipe P3 connected to the liquid tank 27.
The outflow pipes (valve vertical pipes) 263a, 263b of the electronic expansion valves 26a, 26b are linear, and are erected in parallel and perpendicular to each other. Yes.

  The outflow pipes 263a and 263b are connected between the sealing end 25a and the open end 25b of the expansion valve connection pipe 25, and a strainer 44 is provided between the open end 25b and the outflow pipe 263b. In addition, it is preferable that the sealing end 25a has an arc surface and has a refrigerant stirring effect. Further, the strainer 44 is not necessarily provided.

Connected to the open end 25b of the expansion valve connection pipe 25 is a first connection port 24a of the cross pipe 24 which has a cross shape and has four connection ports arranged in a horizontal state.
Further, a collision tube 45 whose end is sealed is connected to the second connection port 24 b opposite to the first connection port 24 a of the cross tube 24. The collision tube 45 is a refrigerant tube whose tip is sealed with a brazing material. In the present embodiment, an example in which the collision tube is manufactured separately and connected to the second connection port will be described. However, the collision tube may be provided integrally with the second connection port.

Further, the third connection port 24c and the fourth connection port 24d which are orthogonal to the first connection port 24a and the second connection port 24b and are provided in a horizontal state have branch pipes P4 (FIG. 3) extending in the horizontal state. P5 is connected, and the branch pipes P4 and P5 extend vertically from a state where they extend horizontally for a predetermined distance.
The branch pipe P4 is connected to the distributor 42a, and the branch pipe P5 is connected to the distributor 42b.

Next, the operation of the heat source unit of the first embodiment will be described.
First, the heating operation will be described.

  During the heating operation, the indoor electronic expansion valve 32 is fully opened, and the outdoor electronic expansion valves 26a and 26b are adjusted to different opening degrees.

  The gas phase refrigerant compressed by the compressor 21 flows into the indoor heat exchanger 31 through the four-way valve 22 and the refrigerant pipe P1.

  The gas-phase refrigerant that has flowed into the indoor heat exchanger 31 is cooled by exchanging heat with the indoor air, becomes a liquid phase, enters the refrigerant pipe P3 via the indoor electronic expansion valve 32, the refrigerant pipe P2, and the liquid tank 27. The branch part P3a is reached. At this time, the room is heated by air heated by heat exchange with the refrigerant.

Further, the liquid-phase refrigerant flows upward in the inflow pipes 262a and 262b, then flows in the horizontal direction, and flows into the outdoor electronic expansion valves 26a and 26b.
The phase refrigerant that has flowed into the outdoor electronic expansion valves 26a and 26b flows down the outflow pipes 263a and 263b that are vertically installed in a gas-liquid two-phase state, and flows into the expansion valve connection pipe 25 that is disposed horizontally.

  The gas-liquid refrigerant that has flowed into the expansion valve connection pipe 25 is mixed together in the expansion valve connection pipe 25. The mixed gas-liquid refrigerant flows into the cross tube 24 from the first connection port 24 a through the strainer 44.

  The gas-liquid refrigerant that has flowed into the cross tube 24 collides with the collision tube 45, flows horizontally through the refrigerant pipes P4 and P5 arranged horizontally, and then flows in the vertical direction through the distributors 42a and 42b. It flows into the outer heat exchangers 23a and 23b and is evaporated. The evaporated refrigerant returns to the compressor 21 via the header 41, the four-way valve 22, and the accumulator 28.

  As described above, in the process in which the refrigerant flows through the outdoor electronic expansion valves 26a and 26b and flows into the outdoor heat exchangers 23a and 23b, the opening degrees of the outdoor electronic expansion valves 26a and 26b are different. When the refrigerant is squeezed by the expansion valves 26a and 26b, a two-phase flow is formed and the flow of the gas phase and the liquid phase is likely to be biased. However, after stirring in the horizontally arranged expansion valve connecting pipe 25, Since the agitation is performed in the collision tube 45 connected to the cross tube 24, the gas phase and the liquid phase are not biased. Furthermore, since the stirred refrigerant is branched by the branch pipes P4 and P5 extending in the horizontal state, the refrigerant can be divided without any bias in the outdoor heat exchangers 23a and 23b.

Next, the cooling operation will be described.
During the cooling operation, the indoor electronic expansion valve 32 is adjusted to a different opening degree, and the outdoor electronic expansion valve 26 is fully opened.

The gas-phase refrigerant compressed by the compressor 21 flows into the outdoor heat exchangers 23a and 23b via the four-way valve 22, the refrigerant pipe P3, and the header 41.
The gas-phase refrigerant that has flowed into the outdoor heat exchangers 23a and 23b is cooled by exchanging heat with outdoor air, and the refrigerant that has become a liquid phase includes the distributors 42a and 42b, the refrigerant pipes P4 and P5, the cross tube 24, and the strainer. 44, flows into the liquid tank 27, the refrigerant pipe P2, and the indoor electronic expansion valve 32 via the expansion valve connecting pipe 25. The refrigerant flowing into the indoor electronic expansion valve 32 is depressurized, evaporated, exchanged heat with indoor air, cooled, and returned to the compressor 21 via the refrigerant pipe P1, the four-way valve 22, and the accumulator 28.

  According to the heat source unit of the first embodiment, the refrigerant flows evenly in the plurality of heat exchangers without any deviation in the refrigerant flow in the branch pipe due to the difference in the opening degrees of the plurality of expansion valves, and the ability can be exhibited. A heat source unit having a refrigeration cycle is realized.

A second embodiment of the heat source unit will be described.
In the second embodiment, the expansion valve connection pipe and the cross pipe are directly connected to each other in the first embodiment, but are connected via a connecting pipe extending substantially vertically.

For example, as shown in FIG. 3, the cross tube 24 used in the second embodiment is connected to the expansion valve connection tube 25 via a connecting tube 51.
The connection pipe 51 is sealed with a collision pipe 52 having one end having an arc surface, and a connection port 51a is provided at the other end, and is arranged substantially vertically.

  The open end 25 b of the expansion valve connection pipe 25 is connected perpendicularly to a substantially middle part of the connection pipe 51, and the first connection port 24 a of the cross pipe 24 is connected to the connection port 51 a of the connection pipe 51. The collision tube 53 connected to the second connection port 24 b of the cross tube 24 has the same shape as the collision tube 52.

  Thereby, while the same effect as 1st Embodiment is acquired, the freedom degree of refrigerant | coolant piping increases. In particular, the connection direction of the branch pipes P4 and P5 extending in the horizontal direction is limited to the direction substantially orthogonal to the expansion valve connection pipe 25 due to the shape of the cross pipe 24 in the first embodiment. In the embodiment, there is no adverse effect on the diversion effect even if the rotation is about ± 30 ° from an angle substantially orthogonal to the expansion valve connecting pipe 25.

  In addition, since the other structure is not different from the expansion valve connecting pipe and the cross pipe shown in FIG.

  DESCRIPTION OF SYMBOLS 1 ... Air conditioning apparatus, 2 ... Outdoor unit, 3 ... Indoor unit, 21 ... Compressor, 22 ... Four-way valve, 23 (23a, 23b) ... Outdoor heat exchanger, 24 ... Cross pipe, 24a ... First connection 24, second connection port, 24c, third connection port, 24d, fourth connection port, 25, expansion valve connection pipe, 25a, sealed end, 25b, open end, 26 (26a, 26b) ... Outside electronic expansion valve, 261a, 261b ... Valve body, 262a, 262b ... Inflow pipe, 263a, 263b ... Outflow pipe, 27 ... Liquid tank, 28 ... Accumulator, 29 ... Outdoor blower, 31 ... Indoor heat exchanger 32 ... Indoor side electronic expansion valve, 33 ... Indoor side blower, 41 ... Header, 42a, 42b ... Distributor, 44 ... Strainer, 45 ... Collision pipe, P, P1, P2, P3 ... Refrigerant piping, P2a ... Branching part, P4 P5 ... branch pipe.

Claims (2)

A heat source unit in which a compressor, a plurality of heat exchangers, and a plurality of expansion valves are connected by refrigerant piping,
Expansion valve connection pipes, wherein the valve bodies of the plurality of expansion valves are connected in parallel in a substantially vertical direction, and are disposed substantially horizontally;
A cross tube connected to the expansion valve connection pipe via a first connection port;
A collision tube connected to the second connection port opposite to the first connection port;
A heat source unit, comprising: a branch pipe that is connected in a horizontal state to the third connection port and the fourth connection port of the cross tube and that divides the refrigerant into the plurality of heat exchangers. A heat source unit in which a compressor, a plurality of heat exchangers, and a plurality of expansion valves are connected by refrigerant piping,
Expansion valve connection pipes, wherein the valve bodies of the plurality of expansion valves are connected in parallel in a substantially vertical direction, and are disposed substantially horizontally;
A connecting pipe that extends substantially vertically and has a lower end sealed, and an intermediate part connected to the expansion valve connecting pipe;
A cross tube whose upper end is sealed and whose lower end is connected to the upper end of the connecting tube;
Heat source unit connected to said cross tube in a horizontal state, characterized in that example Bei a branch pipe which diverts coolant to the plurality of heat exchangers.

Images