DE202014004155U1 - Circular heat exchanger with molded dryer and refrigeration circuit with this heat exchanger - Google Patents

Abstract

A circular heat exchanger (1) comprising: first and second pipelines (30) through which a refrigerant can be passed and which form a first (10) and a second planar spiral (20), the first and second pipelines second pipe (30) are in fluid communication (32) with each other and can be traversed by a common refrigerant.

Description

1. Field of the invention

The present invention relates to a circular heat exchanger and a refrigeration cycle in combination with this circular heat exchanger.

2. Background of the invention

In the prior art, refrigeration circuits are well known, which are used in air conditioning, refrigerators and freezers. Such a refrigeration cycle usually consists of an evaporator in which a refrigerant is evaporated. The required energy is withdrawn from the medium, which is to be washed around the evaporator and cooled. Thereafter, the vaporized refrigerant is supplied to a compressor, where during the compression of the refrigerant, the pressure and the temperature of the refrigerant are increased. In a subsequently installed condenser, the refrigerant is condensed, whereby condensation heat is dissipated to the environment of the condenser. The liquid refrigerant is then supplied to an expansion device, such as an expansion valve, to reduce the pressure in the refrigerant. Within this known refrigeration cycle, heat exchangers are used as evaporator and condenser, respectively, in order to realize an efficient energy exchange between the refrigerant within the heat exchanger and the environment.

Such a refrigeration cycle is in DE 199 05 354 C2 described. The two heat exchangers, which are used as condenser and evaporator, consist of a meander-shaped curved round tube. Such a planar structure is suitable, for example, as a back wall condenser, which is installed at the rear of a freezer.

Out US 1,709,176 is a funnel-shaped arrangement of several circularly curved pipes known to form a heat exchanger. These annular pipes have different diameters and are arranged one behind the other to form a funnel. The individual annular pipes are fastened in two opposite holders, which simultaneously realize the inlet and outlet of the refrigerant.

The complex structure thus requires that each individual annular pipe is individually supplied with refrigerant. In addition, the annular pipes are arranged in the radial edge region of the flow of the medium to be cooled, so that the surface of the heat exchanger is not optimally in contact with the flowing medium.

US 1,635,869 describes a cooling or heating device, which will be described below using the example of the cooling device. This cooling device comprises a centrally arranged fan. In front of and behind the fan in the flow direction in each case a spirally wound coolant line is arranged. This spiral-wound coolant line also has the shape of a funnel. Due to the funnel-shaped spiral initially takes the cooling unit a lot of space. In addition, the fan is enclosed by the two spirals so that it is only accessible with great effort in the event of a defect in need of repair.

Another construction of a heat exchanger is in US 7,367,380 B2 disclosed. Here, a fan is positioned within a sleeve-shaped assembly consisting of a wound wing tube. The air flow to be cooled is guided by the fan through the sleeve-like arrangement, wherein the existing of wing tubes radial inside of the sleeve-like arrangement realizes the heat exchange between the refrigerant and the environment. Another heat exchange between the refrigerant and the flowing environment is ensured by a flat spiral of a pipe, this planar spiral closes the sleeve-like arrangement on one side as far as possible. In order to improve the heat exchange between the refrigerant and the flowing environment, a plurality of sleeve-like arrangements of different diameter are arranged nested. The disadvantage of this design is that different pipes are used for the heat exchange between the refrigerant and the environment. This increases the design and manufacturing costs. In addition, the lines of the refrigerant are in the radial edge region of the medium flow to be cooled. This does not allow the full surface area of the refrigerant line to be used for the required heat exchange.

It is therefore an object of the present invention to provide an alternative to the prior art heat exchanger, which is characterized by an improved heat exchange between the refrigerant and the cooling environment to be cooled.

3. Summary of the invention

The above object is achieved by a circular heat exchanger according to the independent protection claim 1 and by an air conditioning, refrigeration or freezer with a refrigeration cycle according to the independent protection claim 13.

The circular heat exchanger according to the invention has the following features: a first and a second pipe through which a refrigerant is conductive and which form a first and a second planar spiral, wherein the first and the second pipe are in fluid communication with each other and can be flowed through by a common refrigerant.

The heat exchanger according to the invention preferably consists of at least two flat spirals, which are wound from respective pipes. Therefore, this heat exchanger is particularly suitable for installation in pipelines or for placement adjacent to a fan. In this case, the existing of the pipes flat spirals have the advantage that they provide a large area in a space-saving arrangement available, which can be used for heat exchange between the flowing medium and the refrigerant. Depending on the heat exchange performance of the heat exchanger two or more flat spirals can be arranged side by side, in order to optimally adapt the surface of the pipeline of the refrigerant required for cooling purposes.

According to a first preferred embodiment of the present invention, the first and second planar spirals are arranged parallel to each other. Further preferably, the first and / or the second pipe radially extending therefrom wings, preferably two oppositely arranged wings. These per se known wing tubes enlarge the surface of the pipeline, which is available for heat exchange. According to a further preferred embodiment, the wings of the first and / or the second pipeline extend perpendicular or at an angle γ of 0 ° ≤ γ ≤ 90 ° to the radial plane of the first and / or second spiral in which the wings are arranged. By means of a different arrangement of the wings to the radial plane of the respective spiral, it is also possible to adapt to the flow around the surface of the medium to be cooled of the respective spiral. A compromise is to be found between a large area of the wing tube available for the heat exchange and a minimum flow resistance of the planar spiral for the flowing medium to be cooled.

According to a further preferred embodiment of the present invention, the wings within the first and / or second spiral are aligned parallel to one another or not aligned parallel to one another relative to at least two radial regions of the spiral. It is also preferred that the vanes of the first and second spirals are not arranged parallel to one another or parallel to one another or relative to at least two radial regions of the spiral.

Since at least two planar spirals are arranged parallel to one another, in a further preferred embodiment of the present invention the first and second pipelines of the first and second volutes run parallel to one another or radially offset from one another. In this way, the first and second piping of the first and second scrolls according to the first alternative are arranged exactly one behind the other in the flow direction. According to the second alternative, the second pipe of the second spiral is arranged at least partially or completely in the region of the gap between adjacent turns of the first pipe in the first spiral. These designs also allow for heat transfer customization.

Preferably, the first and second conduits are in fluid communication with each other in the central region of the first and second scrolls. According to an alternative of the invention, the first and second pipes are formed by a continuous pipe from which the first and second spirals are wound.

Preferably, the first and / or the second pipe made of steel, copper or aluminum. According to a further preferred embodiment, the heat exchanger at a radially outer end of the first or second pipe to a drying section, which is an integral part of the pipeline or which is integrally formed on the end of the pipe. According to a first alternative, the integral drying section is a tube section of the source tube from which the wing tube of the heat exchanger is formed. Preferably, this first pipe section was not formed into a wing tube, in particular rolled, but left in its original form. Therefore, the integral drying section consists of a round tube section that integrally merges into the wing tube without being deformed for receiving a dryer element. According to a second alternative, the drying section consists of a widened longitudinal section of the first or second pipeline. This construction is suitable when the circular heat exchanger is wound from a source tube with a round cross-section. Since no wings are formed from this original tube, its cross-section is smaller than in the original tube for wing tubes (see above). In the drying section, a dryer element and a sieve are preferably arranged. This dryer element removes disturbing moisture from the passing refrigerant, whereby the screen prevents the dryer element from entering the pipeline. At the downstream end of the drying section, an expansion device for the pressurized refrigerant in the form of a capillary is provided. The capillary is directly or integrally formed from the tube of the Drying section or connected to this by suitable methods, for example by soldering.

The present invention also includes an air conditioning, refrigeration or freezing appliance with a refrigeration cycle, comprising a compressor, an expansion device and at least one heat exchanger according to one of the embodiments described above, which are preferably used as evaporator and / or condenser.

Further, the present invention further discloses a manufacturing method for a circular heat exchanger, comprising the steps of providing first and second pipes as two connected and opposite legs of a U-shaped pipe, simultaneously winding a first planar spiral from the first pipe and a second planar scroll from the second conduit, wherein each of an end of the first and second conduits adjacent a connection between the first and second conduits forms a radial inner beginning of the first and second scrolls.

Two adjacently arranged planar spirals of a first and a second coolant line on the one hand increase the area available for the heat exchange and, moreover, are easy to produce in a combined production process. During the winding of the first spiral, it is readily possible to simultaneously wind the second plane spiral out of the preferably endless pipeline. For this purpose, it is only necessary that from the endless pipe by means of a U-shaped bend two parallel legs are formed, which are subsequently wound with the same or different diameter to two adjacent planar spirals.

In this connection, it is preferable to wind the first and the second pipeline of the first and the second spiral parallel to one another or radially offset relative to one another. According to a further embodiment of the present invention already mentioned above, the first and the second pipeline form a continuous tube, preferably a wing tube. It is further preferred in the manufacture of the circular heat exchanger, the first and second spiral to be arranged parallel to each other.

According to a further preferred embodiment of the manufacturing method according to the invention, the wing tube is wound into a first and a second plane spiral in such a way that the wings, preferably two wings extending radially from a central pipeline and arranged opposite one another, are at least partially parallel within a plane spiral and / or or are aligned at an angle to each other and / or that the wings of adjacent planar spirals are at least partially aligned parallel and / or angled to each other.

Further preferably, the manufacturing method comprises the following further steps: providing a first tube section of a parent tube in cylindrical form as a drying section and forming a wing tube in the adjoining second tube section of the parent pipeline, from which at least the first spiral is formed, and further preferably introducing a drying material in the first pipe section, so that the drying material is held there, preferably by means of a sieve. If the circular heat exchanger is wound from a round tube instead of a wing tube, the manufacturing method has the following preferred further steps: expanding the pipeline of a radially outer end region of a planar spiral over a longitudinal section of the pipeline as a drying section, arranging a dryer element and a sieve within the longitudinal section , According to a further embodiment of the manufacturing method, an integral capillary is formed at the downstream end of the drying section, or a capillary is connected to the end of the first tube section facing away from the wing tube.

4. Brief description of the accompanying drawings

The preferred embodiments of the present invention will be explained in detail with reference to the accompanying drawings. Show it:

1 a schematic representation of a refrigeration cycle of the prior art,

2 A first preferred embodiment of a circular heat exchanger according to the invention in a perspective view,

3 a side view of the circular heat exchanger 2 .

4 a side view of the circular heat exchanger according to 2 with a preferred drying section,

5 a sectional view taken along the line BB 4 .

6 a further side view of the circular heat exchanger according to 2 .

7 a sectional view taken along the line AA 6 .

8th an enlarged view of the circled area 7 .

9 a sectional view of a preferred embodiment of the drying section,

10 an enlarged detail and sectional view of a portion of the drying section 9 and

11 a flow chart of a preferred manufacturing method for the circular heat exchanger according to 2

5. Detailed Description of the Preferred Embodiments

1 describes a known refrigeration cycle consisting of a first heat exchanger WT1 as an evaporator, a compressor V, a second heat exchanger WT2 as a condenser and an expansion device E. The evaporator WT1 is arranged upstream of the compressor V in the flow direction. A refrigerant evaporates in the evaporator WT1 with the heat of vaporization, which is extracted from the environment. In the compressor V, the gaseous refrigerant is compressed. In the second heat exchanger WT2, the refrigerant condenses and thereby releases heat to the environment or to another medium. The high pressure liquid refrigerant is then expanded in the expansion device so that liquid refrigerant is again present under normal pressure conditions.

According to the invention, the first and second heat exchangers WT1, WT2 are preferably a circular heat exchanger 1 used, as in the 2 to 8th is shown in different views according to a preferred embodiment. The circular heat exchanger 1 has a plurality of planar spirals 10 . 20 , preferably two or an integer multiple of two (not shown). These flat spirals 10 . 20 are each from a pipeline 30 wound (step SIII).

Preferably, the pipeline exists 30 of a thermally conductive material, such as metal, in particular of steel, copper, aluminum, alloys thereof or other metal alloys.

For making the two adjacent flat spirals 10 . 20 it is initially preferred to use two pipelines 30 to provide the same or different length (step SI). The two pipes 30 serve at the same time in a manufacturing step, the two flat spirals 10 . 20 to wind (step SIII). For this it is preferable to use the two pipes 30 as only a pipeline with a U-shaped bend 32 provide (SIIa), so that the two pipes 30 which form opposite legs of the U-shaped bent pipes. The U-shaped bend 32 has the advantage of providing a fluid connection between the two pipelines 30 without requiring a liquid-tight connection and a corresponding construction are required.

It is also preferable to use the two pipes 30 provide separately from each other and each liquid-tight at one end to each other, preferably via a U-shaped bent connecting piece to connect with each other (SIIb).

The pipelines 30 consist according to one embodiment of a source tube of circular cross-section, from which then, preferably by rolling, wings have been formed. According to another embodiment, the pipeline is based 30 on a source tube with also circular cross section but smaller diameter than the original tube for the wing tube. From the wing tube or the round tube then preferably the circular heat exchanger is wound.

Below are the interconnected piping 30 simultaneously to two flat spirals 10 . 20 wound (SIII), which in its middle area over the connection 32 connected to each other. It is further preferred that the flat spirals 10 . 20 individually to wrap and then liquid-tight in their middle area to connect together.

Preferably, the flat spirals 10 . 20 wrapped so that the piping 30 in the adjacent flat spirals 10 . 20 parallel to each other. In this case, adjacent pipes point in the same spiral 10 ; 20 (please refer 8th ) the same distance x to each other. It is also preferred to have the distance x within a planar spiral 10 ; 20 to change. According to an alternative (not shown), the distance x ₁ , x _{2 increases} radially outward within the same spiral 10 ; 20 to, in the middle region of the plane spiral 10 ; 20 to provide a larger surface area for heat exchange (see 5 as schematic representation). Similarly, it is preferable that the distance between adjacent pipelines 30 within the same spiral 10 ; 20 decreases radially outward. According to another preferred embodiment of the present invention, the distance between adjacent pipelines 30 in adjacent flat spirals 10 . 20 designed differently. According to one embodiment, the distance between adjacent pipelines 30 in the plane spiral 10 smaller compared to the distance x ₃ in the plane spiral 20 , This will preferably achieves that the first spiraled in the flow direction S flat spiral 10 provides a larger surface area for heat exchange than the flat spiral impinged thereafter 20 , In the same way, it is of course preferred that the first impinged flat spiral 10 with a larger distance x between adjacent pipelines 30 to equip as the then flowed flat spiral 20 , In this way, among other things, the flow resistance of the flat spirals 10 . 20 adaptable to the conditions in the refrigeration cycle.

According to another preferred embodiment of the present invention, adjacent planar spirals become 10 . 20 wound so that they have different sized outer diameter. This may be due to different lengths of piping 30 the plane spirals 10 . 20 or by a variation of the distances x of the adjacent pipelines 30 in the adjacent flat spirals 10 . 20 be achieved. According to a further preferred embodiment of the present invention, the pipelines 30 adjacent planar spirals 10 . 20 so wrapped that the pipeline 30 the second spiral flowed in the direction of flow S flat spiral 20 opposite a pipe space of the planar spiral 10 runs. In this way, the surface of the circular heat exchanger according to the invention which flows through a medium becomes 1 approximately doubled and is adaptable to existing flow conditions.

Because the flat spirals 10 . 20 are connected to each other centrally, is radially on the outside of each flat spiral 10 . 20 an open pipe end 34 intended. Therefore, through the respective pipeline 30 the first level spiral 10 and the second plane spiral 20 a refrigerant can be conducted. Once the first level spiral 10 and the second level spiral 20 are in fluid communication with each other, the pipes of the two flat spirals 10 . 20 flowed through by a common refrigerant.

According to the invention, the first plane spiral is preferred 10 and the second level spiral 20 arranged parallel to each other. To heat exchange between in the pipeline 30 flowing refrigerant and the pipeline 30 To support flowing medium is preferably as a pipeline 30 a wing tube 36 provided (see 8th ). The wing tube 36 includes at least two wings 38 extending radially from the pipeline. Preferably, only two oppositely arranged wings 38 intended. The wings 38 preferably run straight or curved in the radial direction.

According to a preferred embodiment of the present invention, the wing tubes 36 wrapped so that the wings 38 perpendicular to the plane of the plane spiral 10 ; 20 aligned (SIV). In the same way it is preferred the wings 38 the pipeline 30 the first level spiral 10 and / or the pipeline 30 the second plane spiral 20 perpendicular or at an angle γ of 0 ° ≤ γ ≤ 90 ° to the radial plane of the first 10 and / or second plane spiral 20 align (SV). In this context, it is also preferred that the wings 38 within the plane spiral 10 and / or the plane spiral 20 are aligned parallel to each other. According to another preferred alternative of the present invention, the wings are 38 based on at least two radial areas within only one spiral 10 ; 20 not aligned parallel to each other. As a result, within a circular heat exchanger 1 the flow conditions can be influenced by a different angular wing position of the wing 38 in the radial direction of the plane spiral 10 ; 20 different flow conditions on the circular heat exchanger 1 can be achieved. According to another preferred embodiment of the present invention, the wings 38 the plane spiral 10 and the plane spiral 20 aligned parallel to each other. It is also preferable that the wings 38 based on at least two radial regions of the flat spirals 10 . 20 are not aligned parallel to each other in comparison. To these different orientations of the wings 38 with respect to the radial plane RE of the plane spirals 10 . 20 to achieve the wings 38 according to the winding of the flat spirals 10 . 20 oriented.

Preferably, the circular heat exchanger 1 from the two flat spirals 10 . 20 , which in their middle area over the U-shaped bent connector 32 connected together and therefore a continuous pipe 30 for the refrigerant form. The continuous pipeline 30 has an entrance 30E and exit 30A for the refrigerant. According to an embodiment already mentioned above, the heat exchanger 1 an integer multiple of the two plane spirals 10 . 20 on. These are each over the entrance 30E and the exit 30A connected together, ie connected in series and the refrigerant flows in succession through all interconnected spirals, n or two flat spirals 10 . 20 are each connected in pairs to the refrigeration circuit and are therefore not connected in series.

The heat exchanger according to the invention preferably comprises 1 at the exit 30A a drying section 40 , which is liquid-tightly connected to the pipeline or out of the pipeline 30 is formed (SVI).

The drying section 40 has an elongated expanded area 42 on, in which the pipeline 30 to a larger outer diameter compared to the rest of the pipeline 30 has been widened. According to another embodiment of the present invention, the drying section is an undeformed pipe section 42 the source tube from which the wing tube has been formed. Therefore, the drying section is 40 also an integral part of the pipeline, but was not expanded compared to the rest of the pipeline. In the area 42 becomes a drying material 44 brought in. The drying material 44 The refrigerant flows around and extracts moisture from the refrigerant. Preferably, the drying material is 44 as a bulk material, preferably in spherical form, for example in a small bag, as a cylindrical rod, as a plurality of rods or as one or more hollow cylindrical elements. The bulk material 44 has the advantage that it can be filled with inexpensive production in any size tube cross sections, without being impaired in its function. The drying material 44 will be in the area 42 through a sieve 46 held at the downstream end of the area 42 is arranged (see 9 and 10 ).

A drying section connected by soldering to a heat exchanger is in DE 199 05 354 C2 described in this context by reference.

The drying section 40 goes into a capillary at its downstream end 50 above. The capillary 50 serves as an expansion device within the refrigeration cycle according to 1 , This capillary 50 is an integral part of the drying section or connected to it by a separate operation, preferably by soldering.

In the in 1 shown refrigerant circuit, the circular heat exchanger described above is preferably used as a heat exchanger WT1 and / or WT2. For improved operation of the circular heat exchanger 1 is he using a blower or fan L1; L2 combinable. Due to its round shape is the inventively preferred circular heat exchanger 1 by means of a corresponding holder made of plastic or metal within a pipeline, free in space or adjacent to the fan R1; R2 installable.

LIST OF REFERENCE NUMBERS

WT1, WT2

heat exchangers

V

compressor

e

expansion device

L1, L2

Blower / fan

1

circular heat exchanger

10, 20

flat spiral

30

pipeline

30E

entrance

30A

output

32

connection

34

Pipeline end

36

wing tube

38

wing

40

drying section

42

extended area

44

drying material

46

scree

50

capillary

x

Distance between adjacent pipelines

RE

radial plane

S

flow direction

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 19905354 C2 [0003, 0050]
• US 1709176 [0004]
• US 1635869 [0006]
• US 7367380 B2 [0007]

Claims (13)

Circular heat exchanger ( 1 ) having the following features: a first and a second pipeline ( 30 ) through which a refrigerant can be conducted and which is a first ( 10 ) and a second plane spiral ( 20 ), wherein the first and the second pipeline ( 30 ) in liquid communication ( 32 ) are interconnected and can be traversed by a common refrigerant. Heat exchanger ( 1 ) according to claim 1, in which the first ( 10 ) and the second plane spiral ( 20 ) are arranged parallel to each other. Heat exchanger ( 1 ) according to one of the preceding claims, in which the first and / or the second pipeline ( 30 ) wings extending radially therefrom ( 38 ), preferably two oppositely arranged wings ( 38 ). Heat exchanger ( 1 ) according to claim 3, in which the wings ( 38 ) of the first and / or the second pipeline ( 30 ) perpendicular or at an angle γ of 0 ° ≤ γ ≤ 90 ° to the radial plane (RE) of the first ( 10 ) and / or second spiral ( 20 ). Heat exchanger ( 1 ) according to claim 4, in which the wings ( 38 ) within the first ( 10 ) and / or second spiral ( 20 ) parallel to one another or relative to at least two radial regions of the spiral ( 10 ; 20 ) are not aligned parallel to each other. Heat exchanger ( 1 ) according to claim 4, in which the wings ( 38 ) of the first spiral ( 10 ) and the wings ( 38 ) of the second spiral ( 20 ) parallel to one another or relative to at least two radial regions of the spirals ( 10 ; 20 ) are not aligned parallel to each other. Heat exchanger ( 1 ) according to claim 2, in which the first and second pipelines ( 30 ) the first ( 10 ) and second ( 20 ) Spiral parallel to each other or radially offset from each other. Heat exchanger ( 1 ) according to one of the preceding claims, in which the first and the second pipeline ( 30 ) in the middle of the first ( 10 ) and second spiral ( 20 ) in fluid communication with each other ( 32 ) stand. Heat exchanger ( 1 ) according to one of the preceding claims, in which the first and the second pipeline ( 30 ) a continuous pipeline ( 30 ), from which the first ( 10 ) and second spiral ( 20 ) are wound. Heat exchanger ( 1 ) according to one of the preceding claims, comprising more than two each of a pipeline ( 30 ) existing planar spirals ( 10 . 20 ), which are in fluid communication with each other. Heat exchanger ( 1 ) according to one of the preceding claims, in which the first and / or second pipeline ( 30 ) consists of steel, copper or aluminum. Heat exchanger ( 1 ) according to one of the preceding claims, located at a downstream and radially outer end ( 30A ) of the first or second pipeline ( 30 ) a drying section ( 40 ), which is an integral part of the pipeline ( 30 ) or the one at the end ( 30A ) of the pipeline ( 30 ) is formed. Air conditioning, refrigerating or freezing appliance with a refrigeration cycle, comprising a compressor (V), an expansion device (E) and at least one heat exchanger ( 1 ) according to one of the preceding claims, preferably as an evaporator and / or condenser.

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