JP6684652B2 - Double tube heat exchanger - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a double-tube heat exchanger, and more particularly to a double-tube heat exchanger including an outer tube and an inner tube provided at a distance in the outer tube.

  In this specification, the term "condenser" includes a subcool condenser having a condenser section and a supercooling section in addition to a normal condenser.

  Conventionally, as a refrigeration cycle used in a car air conditioner, a compressor, a condenser having a condenser and a supercooler, an evaporator, an expansion valve as a pressure reducer, and a condenser supercooler arranged between the condenser and the evaporator. There is widely known one provided with an intermediate heat exchanger for exchanging heat between the high temperature refrigerant coming out of the evaporator and the low temperature refrigerant coming out of the evaporator.

  In such a refrigeration cycle, it is necessary to reduce the refrigerant pulsation noise of the refrigerant discharged from the compressor. For example, a housing provided between the evaporator and the compressor in a car air conditioner and having a silenced chamber inside is used. The housing is made up of a cylindrical portion whose axis extends vertically, and upper and lower lid portions that close the upper and lower end openings of the cylindrical portion, and an opening hole is formed in the upper lid portion and the opening hole is formed in the opening hole. The inlet side pipe extending from the evaporator is inserted and brazed to the upper lid part, and an opening hole is formed in the peripheral wall of the cylindrical part and the outlet side pipe extending to the compressor is inserted into the opening hole and brazed to the peripheral wall, A muffler is proposed in which both pipes form a right angle, and a bent portion that protrudes into the muffler chamber and is bent toward the lower end of the inlet pipe is provided at the upstream end of the outlet pipe. Are (see Patent Document 1).

  However, in the silencer described in Patent Document 1, the outlet-side pipe whose one end is directly connected to the compressor is brazed to the peripheral wall of the cylindrical portion of the silencer, so the silencer passes through the outlet-side pipe of the engine. It is easily affected by vibration, which may damage the muffler.

JP, 2009-85570, A

  An object of the present invention is to solve the above problems, and to provide a double-tube heat exchanger that includes a silencer that reduces refrigerant pulsation noise and that can prevent damage to the silencer.

  The present invention has the following aspects to achieve the above object.

1) An outer pipe and an inner pipe arranged at a distance in the outer pipe are provided, and a gap between the outer pipe and the inner pipe serves as a first refrigerant flow passage and an inner pipe serves as a second refrigerant flow passage. And a double-tube heat exchanger in which the inner tube has at least one protrusion protruding outwardly from the outer tube,
A muffler is provided on one protruding portion side of the inner pipe, a muffler chamber is provided inside the muffler, which communicates only with the second refrigerant flow passage, and the refrigerant flows through the wall portion surrounding the muffler chamber of the muffler. A large cylindrical portion having a mouth , the silencer is located outside the protruding end of the protruding portion of the inner pipe, and the inner diameter of which is larger than the outer diameter of the outer pipe, and the outer pipe side of the large cylindrical portion. A closing wall which is provided at an end portion on the opposite side to close the opening on the end portion side of the large cylindrical portion, and which is provided on the outer pipe side of the large cylindrical portion and is fitted on the protruding portion of the inner pipe from the outside. A small cylindrical portion that is joined to the outer peripheral surface of the inner pipe, and an outward direction that is provided at the outer pipe side end of the small cylindrical portion and projects radially outward and is joined to the protruding portion side end face of the outer pipe. A flange, and the protrusion-side end opening in the first refrigerant flow path is closed by the outward flange. Double-pipe heat exchanger are.

According to the double-tube heat exchanger of the above 1) , the silencer is provided on the side of one protruding portion of the inner pipe, and the silencer is provided inside the silencer to communicate only with the second refrigerant passage. Since the refrigerant circulation port is formed in the wall portion surrounding the silencer chamber of the silencer, when the refrigerant flows into the silencer chamber through the refrigerant circulation port, the refrigerant pulsation noise of the refrigerant discharged from the compressor is reduced. To be done.

  Further, the refrigerant flowing out of the condenser and heading to the expansion valve is allowed to flow in the first refrigerant flow path, and the refrigerant flowing out of the evaporator and being directed to the compressor is flowed in the second refrigerant flow path. When the pipe extending from the evaporator is connected to the refrigerant flow port of the wall portion surrounding the muffler, the muffler is less susceptible to engine vibration through the compressor, and damage to the muffler can be prevented.

  On the other hand, the refrigerant flowing out of the evaporator and flowing toward the compressor is allowed to flow in the first refrigerant flow path, and the refrigerant flowing out of the condenser and being directed toward the expansion valve is allowed to flow in the second refrigerant flow path, so that the silencer Even if a pipe that extends from the condenser is connected to the refrigerant flow port of the wall that surrounds the muffler, the muffler is less susceptible to engine vibration through the compressor, and damage to the muffler must be prevented. You can

Further, according to the double-tube heat exchanger of 1) above , since the silencer is provided with the outward flange that closes the opening of the end portion on the protruding portion side of the inner pipe in the first refrigerant flow path, the closing member. It is not necessary to prepare separately.

It is a perspective view which abbreviate | omitted the intermediate part of the length direction which shows the whole structure of the double-tube heat exchanger by this invention. FIG. 1 is a vertical vertical sectional view showing an overall configuration of a double-tube heat exchanger according to the present invention, omitting an intermediate portion in a length direction.

  Embodiments of the present invention will be described below with reference to the drawings.

  In the following description, the term "aluminum" includes an aluminum alloy in addition to pure aluminum.

  In the following description, the upper and lower sides and the left and right sides in FIG. 2 are referred to as the upper and lower sides and the left and right sides.

  1 and 2 show the overall structure of a double-tube heat exchanger according to the present invention.

  In FIGS. 1 and 2, a double-tube heat exchanger (1) is concentrically inserted into an outer pipe (2) made of an aluminum extruded profile having a circular cross section and an outer pipe (2) with a space therebetween. Equipped with an inner pipe (3) made of aluminum extruded profile with a circular cross section, and the gap between the outer pipe (2) and the inner pipe (3) becomes the first refrigerant flow path (4), The inside of (3) is the second refrigerant flow path (5).

  A spiral ridge (6) protruding inward is formed on the peripheral wall of the outer tube (2). The projecting end surface of the ridge (6) is located on one cylindrical surface, and the projecting end surface is joined to the outer peripheral surface of the inner pipe (3) with a brazing material. Hereinafter, joining with a brazing material is referred to as brazing. Therefore, the first refrigerant flow path (4) has a spiral shape. Refrigerant inflow leading to the first refrigerant flow path (4) and sending the refrigerant into the first refrigerant flow path (4) near the right end of the portion where the ridge (6) is not formed on the peripheral wall of the outer pipe (2) The pipe (7) is brazed to the left side of the peripheral wall of the outer pipe (2) where the ridge (6) is not formed, and is connected to the first refrigerant flow path (4) and the first refrigerant flow path (4). The refrigerant outflow pipe (8) for sending out the refrigerant from inside 4) is brazed.

  Both ends of the inner pipe (3) project outward from both ends of the outer pipe (2) and have two projecting portions (3a) and (3b). An aluminum silencer (10) is disposed on one of the protrusions (3a) of the inner pipe (3), here the left protrusion (3a) side, and is attached to the outer pipe (2) and the inner pipe (3). It is brazed. In addition, an aluminum closing member (11) for closing the right end opening of the first refrigerant flow path (4) is arranged on the other protruding portion (3b) of the inner pipe (3), and the outer pipe (2) and the inner pipe It is brazed to (3).

  Inside the muffler (10), a muffler chamber (12) communicating only with the second refrigerant flow path (5) is provided, and the muffler (10) has a wall portion surrounding the muffler chamber (12) with the refrigerant. A distribution port (13) is formed. The silencer (10) is integrally formed with a large cylindrical portion (14) having an inner diameter larger than the outer diameter of the outer pipe (2) and one end of the large cylindrical portion (14), here, the left end (here). The closing wall (15) that closes the left end opening of (14) and the right end of the large cylindrical portion (14) are integrally formed to project to the right, and gradually decrease in diameter toward the right and the tip is an inner pipe. Left side of the inner pipe (3) integrally formed at the right end of the taper tube part (16) with the taper tube part (16) reaching the outer peripheral surface of the left side projection part (3a) of (3) and protruding to the right. A small cylindrical part (17), which is fitted from the outside to a fixed length part of the protruding part (3a) and brazed to the outer peripheral surface of the inner pipe (3), is integrally formed at the right end of the small cylindrical part (17). An outer flange (18) that is radially brazed to the left end surface of the outer pipe (2) while the outer peripheral edge of the outer pipe (2) is radially outward of the outer peripheral surface of the outer pipe (2). It is formed integrally with the outer edge of the outward flange (18) and protrudes to the right. It also consists of a middle cylindrical part (19) that is fitted on the outer pipe (2) from the outside to a fixed length near the left end and brazed to the outer peripheral surface of the outer pipe (2). The left end opening of the first refrigerant channel (4) is closed. The refrigerant circulation port (13) is formed on the peripheral wall of the large cylindrical portion (14) of the silencer (10), and the peripheral wall of the large cylindrical portion (14) communicates with the silencer chamber (12) and the refrigerant circulation port. A refrigerant inflow pipe (21) for sending the refrigerant into the muffler chamber (12) through the (13) is connected. The inflow pipe (21) is brazed to the peripheral wall of the large cylindrical portion (14) with its end fitted in the refrigerant flow port (13).

  The closing member (11) is a small cylindrical portion brazed to the outer peripheral surface of the inner pipe (3) by being fitted from the outside to a portion of the rightward protruding portion (3b) of the inner pipe (3) near the outer pipe (2). (22) and the small cylindrical portion (22) are integrally formed at the left end of the small cylindrical portion (22) and project outward in the radial direction, and the outer peripheral edge extends outward in the radial direction from the outer peripheral surface of the outer tube (2). 2) The outward flange (23) brazed to the right end surface of the outer flange (23) and the outer flange (23) are integrally formed on the outer peripheral edge of the outer flange (23) and protrude leftward, and have a constant length near the right end of the outer tube (2). A large cylindrical portion (24) that is fitted onto the outer surface of the outer pipe (2) and brazed to the outer peripheral surface of the outer pipe (2), and the right end opening of the first refrigerant flow path (4) is formed by the outward flange (23). It is blocked.

  The double-tube heat exchanger (1) described above includes, for example, a compressor, a condenser having a condenser, a liquid receiver as a gas-liquid separator and a subcooler, an evaporator, and an expansion valve as a pressure reducer. In the provided refrigeration cycle, it is used as an intermediate heat exchanger for exchanging heat between the refrigerant discharged from the condenser and the refrigerant discharged from the evaporator. The refrigeration cycle is installed in a vehicle, such as an automobile, as a car air conditioner.

  In the case of this refrigeration cycle, the refrigerant inflow pipe (7) brazed to the peripheral wall of the outer pipe (2) of the double pipe heat exchanger (1) is connected to the pipe extending from the supercooling part of the condenser, and A pipe extending to the expansion valve is connected to the refrigerant outflow pipe (8) brazed to the peripheral wall of the outer pipe (2). In addition, the pipe extending from the evaporator is connected to the refrigerant inflow pipe (21) brazed to the peripheral wall of the large cylindrical portion (14) of the silencer (10) of the double-tube heat exchanger (1), and the pipe extending from the evaporator is also connected. A pipe extending to the compressor is connected to an end portion of the pipe (3) located on the right side of the closing member in the right protruding portion (3b) via a joint member (not shown).

  During the operation of the refrigeration cycle, the high-temperature and high-pressure gas-liquid mixed-phase refrigerant compressed by the compressor is cooled and condensed in the condenser of the condenser, and then flows into the receiver to be separated into gas-liquid two-phase. Then, it flows into the supercooling section and is supercooled. The supercooled liquid-phase refrigerant flows through the refrigerant inflow pipe (7) into the first refrigerant flow path (4) of the double-pipe heat exchanger (1), and the first refrigerant flow path (4) After spirally flowing inside, it is sent to the expansion valve through the refrigerant outflow pipe (8). The liquid-phase refrigerant sent to the expansion valve is adiabatically expanded in the expansion valve and decompressed, then flows into the evaporator, and is vaporized in the evaporator.

  On the other hand, the gas-phase refrigerant that has come out of the evaporator passes through the refrigerant inflow pipe (21) and the refrigerant flow port (13), and the silencer chamber (12) of the silencer (10) of the double-tube heat exchanger (1). Then, it flows into the second refrigerant channel (5) through the muffler chamber (12), flows into the second refrigerant channel (5), and then is sent to the compressor. In the double-tube heat exchanger (1), the liquid-phase refrigerant flowing in the first refrigerant channel (4) is further cooled by the relatively low-temperature gas-phase refrigerant flowing in the second refrigerant channel (5). It

  In the car air conditioner described above, the gas-phase refrigerant that has come out of the evaporator passes through the refrigerant inflow pipe (21) and the refrigerant flow port (13), and the silencer (10) of the double-tube heat exchanger (1) is silenced. By flowing into the chamber (12), the refrigerant pulsation noise of the refrigerant discharged from the compressor is reduced.

  In the above embodiment, the refrigerant flowing out of the condenser and heading to the expansion valve flows in the first refrigerant flow path (4), and the refrigerant flowing out of the evaporator and heading to the compressor in the second refrigerant flow path (5). And a pipe extending from the evaporator is connected to the refrigerant flow port (13) of the silencer (10), but the present invention is not limited to this, and the inside of the first refrigerant flow path (4) The refrigerant flowing out of the evaporator and flowing toward the compressor flows, and the refrigerant flowing out of the condenser and flowing toward the expansion valve flows in the second refrigerant flow path (5), and the refrigerant flow port (13) of the silencer (10) ), The pipe extending from the capacitor may be connected.

  The double-tube heat exchanger according to the present invention is arranged between a compressor, a condenser having a condenser and a subcooler, an evaporator, an expansion valve as a pressure reducer, a gas-liquid separator, and a condenser and an evaporator. And in a refrigeration cycle that constitutes a car air conditioner having an intermediate heat exchanger that heat-exchanges the high-temperature refrigerant that has come out of the supercooling section of the condenser and the low-temperature refrigerant that has come out of the evaporator, it is suitable as an intermediate heat exchanger. Used.

(1): Double tube heat exchanger
(2): Outer tube
(3): Inner tube
(3a): Left protrusion
(4): First refrigerant flow path
(5): Second refrigerant channel
(10): silencer
(12): Silencer room
(13): Refrigerant flow port
(14): Large cylinder
(15): Closed wall
(17): Small cylinder
(18): Outward flange

Claims (1)

An outer pipe and an inner pipe arranged at a distance in the outer pipe are provided, and a gap between the outer pipe and the inner pipe serves as a first refrigerant flow passage and an inner pipe serves as a second refrigerant passage. And a double-pipe heat exchanger in which the inner pipe has at least one protrusion protruding outward from the outer pipe,
A muffler is provided on one protruding portion side of the inner pipe, a muffler chamber is provided inside the muffler, which communicates only with the second refrigerant flow passage, and the refrigerant flows through the wall portion surrounding the muffler chamber of the muffler. A large cylindrical portion having a mouth , the silencer is located outside the protruding end of the protruding portion of the inner pipe, and the inner diameter of which is larger than the outer diameter of the outer pipe, and the outer pipe side of the large cylindrical portion. A closing wall which is provided at an end portion on the opposite side to close the opening on the end portion side of the large cylindrical portion, and which is provided on the outer pipe side of the large cylindrical portion and is fitted on the protruding portion of the inner pipe from the outside. A small cylindrical portion that is joined to the outer peripheral surface of the inner pipe, and an outward direction that is provided at the outer pipe side end of the small cylindrical portion and projects radially outward and is joined to the protruding portion side end face of the outer pipe. A flange, and the protrusion-side end opening in the first refrigerant flow path is closed by the outward flange. Double-pipe heat exchanger are.

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