Patent Description:
In a field of refrigeration technology, a heat exchanger, as an important one of four major components of a refrigeration system, plays a role of heat exchange with outside air.

In the prior art, a collecting pipe of the heat exchanger includes a plurality of pipe units, and stress concentration exists on the plurality of pipe units. Under an action of variable load, fatigue fracture is likely to occur, which affects a service life of the heat exchanger.

<CIT> discloses "Heat exchanger, in particular for motor vehicles, with tubes and in each case the ends of the tubes associated with these collecting spaces, the collecting spaces being formed from individual segments, characterized in that adjacent segments (<NUM>) have plug-in connection areas (<NUM>)". <CIT> discloses "To provide a heat exchanger which has an excellent strength against pressure, easiness to be transported on a vehicle and a freedom of the tube pitch by providing the open ends of the tube with an independent tank respectively which is connected to another tank or a plurality of tanks through a nozzle Cooling water enters a tank 2A from a pipe and part of the cooling water goes to a tank 2J through a tube <NUM> and other cooling water goes into a tank 2B through a nozzle <NUM> from a tank 2A and enters the tank 2A through the tube <NUM>. The cooling water which entered the tanks 2J and <NUM> goes into a tank <NUM> and tank <NUM> from the nozzle <NUM>, and then enters tanks 2C and 2D through the tube <NUM>. The cooling water collects to a tank 2E through the nozzle <NUM> and enters a tank 2N through the tube <NUM>. The cooling water cooled by a heat exchanger goes through the nozzle <NUM> of the tank 2N and returns again to the water jacket of an engine by a connected pipe. Since tanks 2A-2N are provided on the sides of the open ends <NUM> and <NUM> of each tube, each tank can be small and its strength against pressure is raised because of a small area to receive pressure". <CIT> discloses a heat exchanger according to the preamble of claim <NUM> and states "To obtain a heat exchanger, easy in the insertion and incorporation of tubes and not necessitating the air-tight inspection of a separator after the incorporation, by a method wherein both ends of the tubes are inserted into a tubular tank previously and fins are arranged between the tubes while each tubular tank is connected to each other continuously so as to obtain a laminated shape. Constitution: Both ends <NUM>, <NUM> of tubes <NUM> are inserted into the inserting ports <NUM> of an intermediate tubular tank <NUM> and are fixed temporarily. Subsequently, the small-diametral parts of respective tubular tanks at the upper side are fitted into the large diametral parts of respective tubular tanks while pinching fins <NUM> between the tubes <NUM> to constitute headers <NUM>, <NUM> and the whole body of a heat exchanger by connecting them continuously. Thereafter, an inlet pipe <NUM> and an outlet pipe <NUM> are incorporated to braze the fins, the tubes and the tubular tanks through integrai brazing and manufacture the heat exchanger. Accordingly, the leakage test of the tubular tanks <NUM> fora separator can be effected upon manufacturing it and, therefore, the air-tight inspection of the separator unit may not be necessitated after the assembling".

According to various embodiments of the present invention, a heat exchanger is provided.

A heat exchanger includes a collecting pipe, and the collecting pipe includes a plurality of pipe units. The plurality of pipe units are sequentially stacked and connected, and each of the plurality of pipe units includes a first section and a second section. A diameter of the first section is less than that of the second section, such that the first section of one of adjacent two of the plurality of pipe units is capable of inserting into the second section of the other of adjacent two of the plurality of pipe units. An arc-shaped section is provided between the first section and the second section of each of the plurality of pipe units, and the arc-shaped section extends to a top of the second section from a bottom of the first section, so that the first section is connected to the second section. And a gap is defined between the first section of the one of adjacent two of the plurality of pipe units and the second section of the other of adjacent two of the plurality of pipe units and in a size of <NUM>.

The collecting pipe described above includes the plurality of pipe units, each of the plurality of pipe units is connected to a heat exchange pipe respectively. In a conventional art, when welding the heat exchanger in a brazing furnace, settlement may occur on the heat exchange pipe and the collecting pipe. The heat exchange pipe is lowered/sunk more serious than the collecting pipe, and these two pipes can not be lowered synchronously. However, in the present disclosure, the first section of one of adjacent two of the plurality of pipe units is inserted into the second section of the other of adjacent two of the plurality of pipe units, providing an expansion allowance for a sinking of each of the plurality of pipe units. So that the collecting pipe and the heat exchange pipe can be lowered/sunk synchronously, and welding efficiency can be improved. In addition, the arc-shaped section is provided between the first section and the second section of each of the plurality of pipe units, which can reduce a stress concentration at a joint between the first section and the second section, and prolong a service life of the heat exchanger.

In one embodiment, a length of the first section along an axis of the collecting pipe is in a range of <NUM> to <NUM>. In this way, the length of the first section can be suitable. It is understood that a flow through the collecting pipe will be reduced if the length of the first section is too great, and it will not be possible to provide the expansion allowance for the sinking of the collecting pipe if a length of the second section is too small.

In this way, the gap between an outer wall of the first section of the one of adjacent two of the plurality of pipe units and an inner wall of the second section of the other of adjacent two of the plurality of pipe units is in a size of <NUM>, which not only enables the first section of one of adjacent two of the plurality of pipe units to insert smoothly into the second section of the other of adjacent two of the plurality of pipe units, but also prevents the gap between the two from being too large and an occurrence of a lack of welding.

In one embodiment, in each of the plurality of pipe units, the first section, the arc-shaped section, and the second section are combined as an integrity structure. In this way, it is possible to simplify a welding process between the first section, the arc-shaped section, and the second section of each of the plurality of pipe units, while avoiding the occurrence of a lack of welding.

In one implementation, a radian of the arc-shaped section of each of the plurality of pipe units is the same. In this way, the radian of the arc-shaped section of each of the plurality of pipe units is the same, so that it is convenient to process.

In one embodiment, the first section is formed by an end of each of the plurality of pipe units via a narrowing-mouth process. In this way, the first section is formed by the end of each of the plurality of pipe units via the narrowing-mouth process, so that the process is simple.

In one embodiment, the heat exchanger further includes a plurality of heat exchange pipes, each of the plurality of pipe units is provided with a slot, and two ends of the plurality of heat exchange pipes are inserted into corresponding slot, resulting in the collecting pipe and the plurality of heat exchange pipes are in communication with each other.

In one embodiment, a top one and a bottom one of the plurality of pipe units are provide with an end cover respectively, and the end cover is configured for sealing the collecting pipe.

In one embodiment, the heat exchanger further includes a plurality of fins disposed between adjacent two of the plurality of heat exchange pipes and distributed from one end of the plurality of heat exchange pipes to the other end thereof. In this way, the fin is configured for accelerating a heat exchange between the heat exchanger and outside air.

A refrigeration system including a compressor, a throttling element, and the heat exchanger as described above is further provided. And the heat exchanger is connected and in communication with the compressor and the throttling element respectively.

The accompanying drawings constituting a part of this invention are used to provide a further understanding of this invention, and the schematic embodiments of this invention and a description thereof are used to explain this invention and do not constitute an undue limitation of this invention which is defined by the appended claims.

In order to illustrate the technical solutions in embodiments of the present invention more clearly, the following briefly introduces the drawings that are used in the description of the embodiments. It is apparent that the drawings in the following description are only some of the embodiments of the present invention, for those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

In the figures, <NUM> represents a refrigeration system, <NUM> represents a heat exchanger, <NUM> represents a collecting pipe, <NUM> represents a slot, <NUM> represents a connecting pipe, <NUM> represents a pipe units, <NUM> represents a first section, <NUM> represents a second section, <NUM> represents an arc-shaped section, <NUM> represents an end cover, <NUM> represents a heat exchange pipe, <NUM> represents a fin, <NUM> represents a sideboard, <NUM> represents a compressor, and <NUM> represents a throttling element.

A clear and complete description of the technical solutions in the embodiments of the present invention will be given below in conjunction with the accompanying drawings in the embodiments of the present invention. It will be apparent that the described embodiments are only a part and not all of the embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention provided they are within the scope of the appended claims.

It should be noted that when an element is referred to as being "arranged" on another element, it may be directly arranged on the other element or a further element may be presented between them. When an element is referred to as being "disposed" on another element, it may be directly disposed on the other element or a further element may be presented between them. When an element is referred to as being "fixed" to another element, it may be directly attached to the other element or a further element may be presented between them.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art of the present invention. The term "or/and" as used herein includes any and all combinations of one or more of the associated listed items.

Referring to <FIG>, the present invention provides a refrigeration system <NUM>. The refrigeration system <NUM> is applied to a cold chain system such as a household air conditioner, a refrigerator, a commercial air conditioner freezer, or a cold storage, or other occasions that need to reduce or raise a temperature of natural environment.

The refrigeration system <NUM> includes a compressor <NUM>, a throttling element <NUM> and a heat exchanger <NUM>, and the compressor <NUM>, the throttling element <NUM> and the heat exchanger <NUM> are connected to each other by pipelines. Other accessories such as liquid reservoirs and gas-liquid separators between the compressor <NUM>, the throttling element <NUM> and the heat exchanger <NUM> can also be provided.

Referring to <FIG>, the heat exchanger <NUM> includes a collecting pipe <NUM> and a plurality of heat exchange pipes <NUM>. The collecting pipe <NUM> is disposed at both ends of the heat exchange pipe <NUM>, respectively, and the plurality of heat exchange pipes <NUM> are arranged in parallel with each other. The collecting pipe <NUM> is provided with a plurality of slots <NUM>, and the plurality of heat exchange pipes <NUM> are inserted into corresponding slot <NUM>, resulting in the collecting pipe <NUM> and the plurality of heat exchange pipes <NUM> are in communication with each other. The number of the heat exchange pipes <NUM> corresponds to the number of the slots <NUM> one-to-one.

Specifically, the heat exchanger <NUM> further includes a plurality of fins <NUM> disposed between adjacent two of the plurality of heat exchange pipes <NUM>, that is, a fin <NUM> is disposed between adjacent two of the plurality of heat exchange pipes <NUM>. The plurality of fins <NUM> are distributed from one end of the plurality of heat exchange pipes to the other end thereof, thus enhancing a heat exchange between a medium in the heat exchange pipe <NUM> and the external environment.

Furthermore, the heat exchanger <NUM> further includes two sideboards <NUM>, the two sideboards <NUM> are disposed on an outside of a top one and a bottom one of the plurality of fins <NUM> respectively, and fixed to the top one and the bottom one of the plurality of fins <NUM> respectively to protect them.

The collecting pipes <NUM> are located on both sides of the heat exchange pipe <NUM>, that is, the number of the collecting pipes <NUM> is two, and an end of each of the collecting pipes <NUM> is provided with a connecting pipe <NUM>, wherein one of the connecting pipes <NUM> is defined as an inlet connecting pipe <NUM>, and the other thereof is defined as an outlet connecting pipe <NUM>, and medium flows into the collecting pipes <NUM> by the inlet connecting pipe <NUM> and flows out the collecting pipe <NUM> by the outlet connecting pipe <NUM>. When the heat exchanger <NUM> is used as a condenser, the medium in the heat exchange pipe <NUM> releases heat to outside environment via the plurality of fins <NUM>. The inlet connecting pipe <NUM> is connected to an outlet of the compressor <NUM>, and the outlet connecting pipe <NUM> is connected to an inlet of the throttling element <NUM>. Of course, other accessories such as oil separators can be provided between the inlet connecting pipe <NUM> and the compressor <NUM>, and other accessories such as reservoirs can be provided between the outlet connecting pipe <NUM> and the throttling element <NUM>. When the heat exchanger <NUM> is used as an evaporator, the medium in the heat exchange pipe <NUM> absorbs heat from outside environment via the plurality of fins <NUM>. The inlet connecting pipe <NUM> is connected to an outlet of the throttling element <NUM>, the outlet connecting pipe <NUM> is connected to an inlet of the compressor <NUM>. Of course, other accessories such as ball valves can be provided between the inlet connecting pipe <NUM> and the throttling element <NUM>, and other accessories such as gas-liquid separators can be provided between the outlet connecting pipe <NUM> and the compressor <NUM>.

Referring to <FIG>, the collecting pipe <NUM> includes a plurality of pipe units <NUM>, and the plurality of pipe units <NUM> are sequentially stacked and connected along an axis of the collecting pipe.

Specifically, each of the plurality of pipe units <NUM> includes a first section <NUM> and a second section <NUM>, and a diameter of the first section <NUM> is less than that of the second section <NUM>, such that the first section <NUM> of one of adjacent two of the plurality of pipe units <NUM> is capable of being inserted into and fixed to the second section <NUM> of the other of adjacent two of the plurality of pipe units <NUM> by welding process.

It is understood that before welding, surfaces of the collecting pipe <NUM> and the heat exchange pipe <NUM> are coated with a composite layer. It is necessary to explain that the composite layer is a brazing material. In a conventional art, during welding, the heat exchanger <NUM> is placed in a brazing furnace, and high temperature environment causes the brazing material to melt, so that the heat exchange pipe <NUM> and the collecting pipe <NUM> are lowered/sunk, and the heat exchange pipe <NUM> is lowered/sunk more significant than the collecting pipe <NUM>. Two ends of the plurality of heat exchange pipes <NUM> are inserted into corresponding slot <NUM> of the collecting pipe <NUM> and restricted by a notch of the slot <NUM>, a sinking in a middle of the heat exchange pipe <NUM> may be more serious than that of the both sides. An overall structure of the heat exchange pipe <NUM> may be deformed, and the heat exchange pipe <NUM> and the slot <NUM> may be also tilted, which can easily lead to virtual welding and desoldering during welding. However, in the present invention, the first section of one of adjacent two of the plurality of pipe units is inserted into the second section of the other of adjacent two of the plurality of pipe units, providing an expansion allowance for a sinking of each of the plurality of pipe units. So that the collecting pipe and the heat exchange pipe are lowered/sunk synchronously, and welding efficiency is improved.

Furthermore, an arc-shaped section is provided between the first section and the second section of each of the plurality of pipe units, and the arc-shaped section extends to a top of the second section from a bottom of the first section, thus avoiding a stress concentration due to the direct connection between the first section <NUM> and the second section <NUM>. Since the medium inside the collecting pipe <NUM> is in a variable load, that is, an impact force of the medium inside the collecting pipe <NUM> on an inner wall of the collecting pipe <NUM> is not constant. Under a long-term impact of the medium or a vibrating environment, a direct connection between the first section <NUM> and the second section <NUM> will cause a joint between the first section <NUM> and the second section <NUM> to fracture due to the stress concentration. The arc-shaped section <NUM> can reduce the stress concentration between the two and prolong a service life of the heat exchanger <NUM>.

Alternatively, a length of the first section <NUM> along an axis of the collecting pipe <NUM> is in a range of <NUM> to <NUM>. It is understood that a flow through the collecting pipe <NUM> will be reduced if the length of the first section <NUM> is too great, and it will not be possible to provide the expansion allowance for the sinking of collecting pipe <NUM> if a length of the second section <NUM> is too small. Therefore, <NUM> to <NUM> of the length of the first section <NUM> can be a suitable range. The length of the first section <NUM> can be <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or any value between <NUM> to <NUM>.

Before welding, the first section <NUM> of one of adjacent two of the plurality of pipe units <NUM> is inserted into the second section <NUM> of the other of adjacent two of the plurality of pipe units <NUM>, and a depth of a insertion part of the first section <NUM> is less than the length of the first section <NUM> to provide an expansion allowance for the sinking of each of the plurality of pipe units <NUM>.

Preferably, in the present embodiment, the length of the first section <NUM> is <NUM>, and the depth of the insertion part of the first section <NUM> is <NUM>. In other embodiments, the length of the first section <NUM> can be other values, and the depth of the insertion part of the first section <NUM> can be other values.

A gap is defined between the first section <NUM> of the one of adjacent two of the plurality of pipe units <NUM> and the second section <NUM> of the other of adjacent two of the plurality of pipe units <NUM> and in a size of <NUM>. Said gap between the first section <NUM> of the one of adjacent two of the plurality of pipe units <NUM> and the second section <NUM> of the other of adjacent two of the plurality of pipe units <NUM>, not only enables the first section <NUM> of one of adjacent two of the plurality of pipe units <NUM> to insert smoothly into the second section <NUM> of the other of adjacent two of the plurality of pipe units <NUM>, but also prevents the gap between the two from being too large and an occurrence of lack of welding.

Furthermore, in each of the plurality of pipe units <NUM>, the first section <NUM>, the arc-shaped section <NUM>, and the second section <NUM> are combined as an integrity structure. In this way, it is possible to simplify a welding process between the first section <NUM>, the arc-shaped section <NUM>, and the second section <NUM> of each of the plurality of pipe units <NUM>, thus avoiding the occurrence of lack of welding and increasing reliability of the heat exchanger <NUM>.

Referring to <FIG>, the first section <NUM> is formed by an end of each of the plurality of pipe units <NUM> via a narrowing-mouth process. The process is simple and requires no additional welding.

Preferably, a length of each of the plurality of pipe units <NUM> is the same, a height of each of the plurality of pipe units <NUM> is all the same. The length of the first section <NUM> of each of the plurality of pipe units <NUM> is the same, an inner diameter of the first section <NUM> of each of the plurality of pipe units <NUM> is all the same, an outer diameter of the first section <NUM> of each of the plurality of pipe units <NUM> is the same. The length of the second section <NUM> of each of the plurality of pipe units <NUM> is the same, an inner diameter of the second section <NUM> of each of the plurality of pipe units <NUM> is all the same, an outer diameter of the second section <NUM> of each of the plurality of pipe units <NUM> is the same. A radian of the arc-shaped section <NUM> of each of the plurality of pipe units <NUM> is the same, and it is convenient to process. Of course, in other embodiments, according to different designs, the length and the height of each of the plurality of pipe units <NUM> can be different, the length, the inner diameter and the outer diameter of the first section <NUM> and the second section <NUM> of each section of the pipe unit <NUM> can also be different, and the radian of the arc-shaped section <NUM> of each of the plurality of pipe units <NUM> can also be different.

A top one and a bottom one of the plurality of pipe units <NUM> are provide with an end cover <NUM> respectively, that is, both ends of the collecting pipe <NUM> are provided with the end cover <NUM>. The end cover <NUM> is configured for sealing the collecting pipe <NUM> to prevent the medium inside the collecting pipe <NUM> from getting leakage.

During an assembly process, the first section <NUM> of one of adjacent two of the plurality of pipe units <NUM> is inserted into the second section <NUM> of the other of adjacent two of the plurality of pipe units <NUM>, and surfaces of the collecting pipe <NUM> and the heat exchange pipe <NUM> are coated with the composite layer. Then the plurality of heat exchange pipes <NUM> are inserted into corresponding slot <NUM> and put into the brazing furnace for welding. The composite layer is melted due to high temperature, so that the heat exchange pipe <NUM> and the collecting pipe <NUM> may be lowered/sunk. The collecting pipe <NUM> has the expansion allowance due to a mutual insertion between the first section <NUM> and the second section <NUM> of the plurality of pipe units <NUM>, so that the collecting pipe <NUM> and the heat exchange pipe <NUM> are lowered synchronously. After the composite layer is melted, the plurality of pipe units <NUM> and the heat exchange pipe <NUM> are welded into a whole.

During a working process, the arc-shaped section <NUM> between the first section <NUM> and the second section <NUM> can reduce the stress concentration at the joint between the first section <NUM> and the second section <NUM>, which can prevent from breakage under a long-term use in the vibrating environment or the impact of the medium.

Claim 1:
A heat exchanger (<NUM>) comprising a collecting pipe (<NUM>), wherein the collecting pipe (<NUM>) comprises a plurality of pipe units (<NUM>), the plurality of pipe units (<NUM>) are sequentially stacked and connected, each of the plurality of pipe units (<NUM>) comprises a first section (<NUM>) and a second section (<NUM>), and a diameter of the first section (<NUM>) is less than that of the second section (<NUM>), such that the first section (<NUM>) of one of adjacent two of the plurality of pipe units (<NUM>) is capable of inserting into the second section (<NUM>) of the other of adjacent two of the plurality of pipe units (<NUM>),
an arc-shaped section (<NUM>) is provided between the first section (<NUM>) and the second section (<NUM>) of each of the plurality of pipe units (<NUM>), and the arc-shaped section (<NUM>) extends to a top of the second section (<NUM>) from a bottom of the first section (<NUM>), so that the first section (<NUM>) is connected to the second section (<NUM>), characterized in that
a gap is defined between the first section (<NUM>) of the one of adjacent two of the plurality of pipe units (<NUM>) and the second section (<NUM>) of the other of adjacent two of the plurality of pipe units (<NUM>) and in a size of <NUM>.