WO2023202300A1

WO2023202300A1 - Method for forming air return pipe, forming die and air return pipe

Info

Publication number: WO2023202300A1
Application number: PCT/CN2023/082535
Authority: WO
Inventors: 刘晓军; 陈小华; 张如存; 贾丽
Original assignee: 合肥美的电冰箱有限公司; 合肥华凌股份有限公司; 美的集团股份有限公司
Priority date: 2022-04-21
Filing date: 2023-03-20
Publication date: 2023-10-26
Also published as: CN116967303A

Abstract

A method for forming an air return pipe, comprising: controlling a blank (26) to enter a forming cavity, controlling a die core (23) to press the blank (26) such that the blank (26) passes through a first die body (21), and obtaining a first length value of a first formed pipe section formed by the first die body (21); determining that the first length value reaches a first set parameter value, controlling a second die body (22) to press part of the first formed pipe section such that the part of the first formed pipe section is formed into a second formed pipe section, and obtaining a second length value of the second formed pipe section; determining that the second length value reaches a second set parameter value, and controlling the second die body (22) to stop pressing; and controlling a third formed pipe section formed by the first die body (21) to reach a third set parameter value. A forming die (20), comprising the die core (23), the first die body (21) and the second die body (22), wherein the forming cavity is formed between the die core (23) and the first die body (21), the second die body (22) is arranged on one side of a discharge end of the first die body (21) and is provided with a protrusion (223) facing a center of the second die body (22). An air return pipe (10), comprising a first pipe section (11), a second pipe section (12) and a third pipe section (14) which are formed by pressing, wherein the second pipe section (12) is located between the first pipe section (11) and the third pipe section (14), the second pipe section (12) is provided with an accommodation portion, and the accommodation portion is recessed towards a center of the second pipe section (12) and extends in an axial direction of the second pipe section (12). The plurality of pipe sections having different cross-sectional shapes are continuously pressed, so that the plurality of pipe sections are integrally formed, thereby eliminating welding spots between every two adjacent pipe sections, and reducing the leakage risk of the air return pipe.

Description

Return air pipe forming method, molding mold and return air pipe

Cross-references to related applications

This application claims the priority of the Chinese patent application with application number 202210424814.2 submitted on April 21, 2022, and the invention name is "Return Air Pipe Forming Method, Forming Mold and Return Air Pipe", which is fully incorporated herein by reference.

Technical field

The present application relates to the technical field of refrigeration equipment, and in particular to a method for forming a return air pipe, a forming mold and a return air pipe.

Background technique

The heat exchange tubes used in refrigeration equipment are generally return air pipes and capillary tubes. The return air pipe has a circular cross-section and is fixed with the capillary tube through aluminum foil, heat shrink tube, etc. for heat exchange. There is linear contact between the return air pipe and the capillary tube, and the heat exchange efficiency is low.

In order to improve the heat exchange efficiency, the capillary tube is embedded in the return pipe to improve the heat exchange efficiency. In the related art, circular cross-section connecting pipes are added to both ends of the return pipe, and the connecting pipes are connected to the evaporator and the compressor.

Although adding connecting pipes at both ends of the return air pipe can connect the return air pipe to the evaporator and compressor, due to the welding between the connecting pipe and the return air pipe, leakage is prone to occur at the weld position, which increases the risk of foaming of the return air pipe in the refrigeration equipment. The risk of leakage within the layer affects the reliability of the refrigeration equipment.

Contents of the invention

This application aims to solve at least one of the technical problems existing in the related art. To this end, the first aspect of this application provides a method for forming return air ducts, which can be continuously extruded to form return air ducts with different cross-sectional shapes, with good cross-sectional consistency, while meeting the heat exchange requirements and connection requirements of the return air ducts.

A second aspect of this application provides a forming mold.

A third aspect of this application provides an air return pipe.

The method for forming the return air pipe provided according to the embodiment of the present application includes:

Control the blank to enter the molding cavity, and control the mold core to squeeze the blank so that the blank passes through the first a mold body, and obtain the first length value of the first formed pipe section formed by the first mold body;

Determine that the first length value reaches the first set parameter value, control the second mold body to extrude part of the first formed pipe section, so that the part of the first formed pipe section is formed into a second formed pipe section, and obtain the second formed pipe section. second length value;

Determine that the second length value reaches the second set parameter value, and control the second mold body to stop extrusion;

Controlling the third forming pipe section formed by the first mold body to reach a third set parameter value;

Wherein, the cross-sectional shape of the first mold body is different from the cross-sectional shape of the second mold body.

According to the forming method of the return air pipe according to the embodiment of the present application, multiple pipe sections with different cross-sectional shapes can be continuously extruded through this forming method, so that the multiple pipe sections can be integrally formed and the solder joints between two adjacent pipe sections can be eliminated. , reducing the risk of leakage in the return pipe. It not only ensures the cross-section consistency of the return air pipe, but also meets the heat exchange and connection requirements of the return air pipe.

According to the molding mold provided by the present application, used to perform the molding method of the return air duct according to any one of the above, it includes a mold core, a first mold body and a second mold body, and the relationship between the mold core and the first mold body is A molding cavity is formed between them;

The second mold body is located on one side of the discharge end of the first mold body. The second mold body includes a first sub-mold body and a second sub-mold body located on one side of the first sub-mold body. , the first sub-mold body or the second sub-mold body is provided with a protruding portion, and the protruding portion faces the center of the second mold body.

According to the molding mold provided by the embodiment of the present application, return air pipes with different cross-sectional shapes can be continuously extruded to meet the production needs of continuous extrusion of return air pipes; at the same time, the formed return air pipes have stable dimensions, good cross-sectional consistency, simple molding process, and easy operation convenient.

The air return pipe provided according to the present application includes an extruded first pipe section, a second pipe section and a third pipe section. The second pipe section is located between the first pipe section and the second pipe section. The second pipe section The pipe section is configured with a receiving portion which is recessed toward the center of the second pipe section and extends along the axial direction of the second pipe section.

According to the air return pipe provided by this application, the first pipe section, the second pipe section and the third pipe section are integrally formed, and the second pipe section is constructed with a receiving part, so that the air return pipe can not only increase the contact area with the capillary tube, but also improve the heat exchange efficiency , and facilitates the connection of the return pipe, eliminating the need for two adjacent moldings Welded joints between pipe sections reduce the risk of leakage in the return pipe.

Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application.

Description of the drawings

In order to more clearly explain the technical solutions in the embodiments of the present application or related technologies, the drawings needed to be used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings in the following description are only for the purpose of describing the embodiments or related technologies. For some embodiments of the application, those of ordinary skill in the art can also obtain other drawings based on these drawings without exerting creative efforts.

Figure 1 is a schematic flow chart of a method for forming an air return pipe provided by an embodiment of the present application;

Figure 2 is a schematic flow chart of the forming method of the air return pipe provided by the embodiment of the present application;

Figure 3 is one of the cross-sectional views of the forming mold provided by the embodiment of the present application;

Figure 4 is a view from direction A in Figure 3;

Figure 5 is the second cross-sectional view of the forming mold provided by the embodiment of the present application;

Figure 6 is a view from direction B in Figure 5;

Figure 7 is one of the forming schematic diagrams of the forming method of the return air pipe provided by the embodiment of the present application;

Figure 8 is the second schematic diagram of the forming method of the return air pipe provided by the embodiment of the present application;

Figure 9 is a schematic structural diagram of an air return pipe provided by an embodiment of the present application.

Reference signs:

10. Return air pipe; 11. First pipe section; 12. Second pipe section; 13. Gradient pipe section; 14. Third pipe section;

20. Forming mold; 21. First mold body; 211. First sub-mold body; 212. Second sub-mold body; 213. First mold cavity; 22. Second mold body; 221. Third sub-mold body; 222. Fourth sub-mold body; 223. Protruding part; 224. Second mold cavity; 23. Mold core; 231. Molding part; 232. Recessed part; 24. Driving mechanism; 25. Driving assembly; 26. Blank.

Detailed ways

The embodiments of the present application will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate the present application but cannot be used to limit the scope of the present application.

In the description of the embodiments of this application, it should be noted that the terms "center", "longitudinal", "horizontal", "top", "bottom", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", " The orientation or positional relationship indicated by "outside" and so on is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation. , are constructed and operated in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present application. Furthermore, the terms “first”, “second” and “third” are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the embodiments of this application, it should be noted that, unless otherwise clearly stated and limited, the terms "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection. Or integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood in specific situations.

In the embodiments of this application, unless otherwise expressly provided and limited, the first feature "on" or "below" the second feature may be that the first and second features are in direct contact, or the first and second features are in intermediate contact. Indirect media contact. Furthermore, the terms "above", "above" and "above" the first feature is above the second feature may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is higher in level than the second feature. "Below", "below" and "beneath" the first feature to the second feature may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature has a smaller horizontal height than the second feature.

In the description of this specification, reference to the terms "one embodiment," "some embodiments," "an example," "specific examples," or "some examples" or the like means that specific features are described in connection with the embodiment or example. , structures, materials or features are included in at least one embodiment or example of the embodiments of this application. In this specification, the schematic expressions of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, those skilled in the art may combine and combine different embodiments or examples and features of different embodiments or examples described in this specification unless they are inconsistent with each other.

The serial numbers of the components in the embodiments of this application, such as "first", "second"; (1), (2), (3); step one, step two, etc., are only used to distinguish the described objects. Does not have any sequential or technical meaning. Unless otherwise stated, "plurality" means two or more. This application The words "including", "including", "having", "containing", etc. used in the embodiments are all open terms, which mean including but not limited to. The term "and/or" in the embodiment of this application is only an association relationship describing associated objects, indicating that there can be three relationships, for example, A and/or B, which can mean: A alone exists, and A and B exist simultaneously. , there are three situations of B alone. In the embodiments of this application, words such as "exemplary" or "for example" are used to represent examples, illustrations or explanations. Any embodiment or design described as "exemplary" or "such as" in the embodiments of the application is not to be construed as preferred or advantageous over other embodiments or designs. Rather, use of the words "exemplary" or "such as" is intended to present the concept in a concrete manner. Unless otherwise defined, all technical and scientific terms used in the embodiments of this application have the same meanings as commonly understood by those skilled in the technical field of this application. If there is any inconsistency, the meaning explained in this manual or the meaning derived from the content recorded in this manual shall prevail.

Referring to Figures 3 to 6 in detail, one aspect of the present application provides a molding mold, which includes a mold core 23, a first mold body 21 and a second mold body 22. A molding is formed between the mold core 23 and the first mold body 21. cavity.

As shown in Figures 4 and 6, in order to facilitate processing of the first mold body 21, the first mold body 21 can be configured as a split structure, that is, the first mold body 21 includes a first sub-mold body 211 and a second sub-mold body. 212. After the first sub-mold body 211 and the second sub-mold body 212 are molded together, they are used for primary extrusion molding of the pipe body.

The second mold body 22 is located on the discharge end side of the first mold body 21. The second mold body 22 includes a third sub-mold body 221 and a fourth sub-mold body 222 located on one side of the third sub-mold body 221. The third sub-mold body 221 or the fourth sub-mold body 222 is provided with a protruding portion 223, and the protruding portion 223 is disposed toward the center of the second mold body 22. After the third sub-mold body 221 and the fourth sub-mold body 222 are molded together, they can At least one depression is formed on the surface of the pipe extruded through the second mold body 22 .

It can be understood that the first mold body 21 is used to shape the entire pipe body of the return pipe 10, and the second mold body 22 is disposed at the rear end of the first mold body 21, that is, the second mold body 22 is located at the first mold body 21 for molding. The protruding side of the pipe section forms a depression in the entire pipe body formed by the first mold body 21, that is, a special-shaped cross-section structure, which is equivalent to the second mold body 22 being in the first mold body 21. Based on the molding process again.

In some embodiments of the present application, as shown in Figures 4 and 6, the second mold body 22 faces the blank. A raised portion 223 is provided on one side of the material 26 . Specifically, the protruding portion 223 can be formed on either the third sub-mold body 221 or the fourth sub-mold body 222, that is, any one of the third sub-mold body 221 and the fourth sub-mold body 222. A protruding portion 223 corresponding to the recessed structure is provided toward the center of the second mold body 22 .

When the protruding portion 223 is disposed on the third sub-mold body 221, correspondingly, the third sub-mold body 221 is connected to the driving mechanism 24; when the protruding portion 223 is disposed on the fourth sub-mold body 222, correspondingly, the fourth The driving mechanism 24 is connected to the sub-mold body 222; when the protruding portion 223 is provided on both the third sub-mold body 221 and the fourth sub-mold body 222, correspondingly, the third sub-mold body 221 and the fourth sub-mold body 222 The driving mechanisms 24 are respectively connected to the four sub-mold bodies 222 .

In some embodiments of the present application, the driving mechanism 24 may include a cylinder and its connecting pipelines, or the driving mechanism 24 may include an oil cylinder and its connecting pipelines, etc., as long as linear reciprocating movement can be achieved to control the movement of the third sub-mold body 221 Any driving member that can be molded together with the fourth sub-mold body 222 and can be separated from the fourth sub-mold body 222 can be used.

In some embodiments of the present application, preferably, the driving mechanism 24 and the protruding portion 223 are provided on the same component, that is, the driving mechanism 24 is connected to the third sub-mold body 221. Under the action of the driving mechanism 24, the third sub-mold body 221 is The mold body 221 is movable relative to the fourth sub-mold body 222 and is adapted to switch between the first position W1 and the second position W2.

At the first position W1, as shown in FIG. 6, the third sub-mold body 221 and the fourth sub-mold body 222 are closed, that is, the third sub-mold body 221 moves downward relative to the fourth sub-mold body 222. The four sub-mold bodies 222 are located. At this time, the blank 26 is extruded through the first mold body 21 to form a tube body with a circular cross-section, and then is extruded through the second mold body 22 to form a receiving portion with embedded capillary tubes, that is, The second molded pipe section with special-shaped cross-section. At this time, the first mold body 21 and the second mold body 22 cooperate with the extrusion equipment to continuously extrude the circular cross-section pipe section and the special-shaped cross-section pipe section.

At the second position W2, as shown in Figure 4, the third sub-mold body 221 is separated from the fourth sub-mold body 222, that is, the third sub-mold body 221 moves upward to a set distance relative to the fourth sub-mold body 222. , the set distance can be an interval value, that is, as long as the third sub-mold body 221 does not interfere with the blank 26 being extruded into a circular cross-section tube; the set distance can also be a fixed value, at the fixed value, The third sub-mold body 221 does not interfere with the blank 26 and is extruded into a circular cross-section tube.

At this time, the blank 26 is extruded through the first mold body 21 to form a pipe body with a circular cross-section. The fourth sub-mold body 222 in the second mold body 22 is only used for supporting. Therefore, the first mold body 21 The second mold body 22 cooperates with the extrusion equipment to extrude a pipe section with a circular cross-section, which is equivalent to the second mold body 22 retaining the pipe structure formed by the first mold body 21 .

During the switching process from the second position W2 to the first position W1, the driving mechanism 24 controls the third sub-mold body 221 to gradually approach the fourth sub-mold body 222, so that the air return pipe 10 is formed with a connection between two different cross-sectional shapes. Gradient pipe section 13.

As shown in FIGS. 7 and 8 , as some embodiments of the present application, at least one of a first position sensor, a second position sensor and a third position sensor is provided at intervals at the rear end of the forming mold 20 , that is, at the second A first position sensor, a second position sensor and a third position sensor are arranged at intervals on the side of the mold body 22 facing away from the first mold body 21. The second position sensor may be arranged between the first position sensor and the third position sensor.

The first position sensor is used to detect that the starting end of the return air pipe 10 reaches the first preset position, and outputs a signal to the control system to control the second mold body 22 to approach the blank 26 and start extrusion work.

That is, as shown in Figures 8 and 9, on the side extending out of the forming mold 20, along the conveying path of the return air pipe 10, according to the length design requirements of the return air pipe 10, at the corresponding position of the first set parameter value L1 The first position sensor is set. When the starting end of the return air pipe 10 reaches the position of the first position sensor, it means that the length of the circular cross-section pipe section meets the requirements of the first set parameter value L1, and the first position sensor transmits a signal to the control system, after receiving the signal, the control system makes the second mold body 22 gradually approach the blank 26 until the blank 26 is extruded to form a special-shaped cross-section pipe section.

The second position sensor is used to detect that the starting end of the return air pipe 10 reaches the second preset position, and outputs a signal to the control system to control the second mold body 22 to move away from the blank 26 and stop the extrusion work.

That is to say, along the transportation path of the return air pipe 10, downstream of the first position sensor, according to the length design requirements of the return air pipe 10, a second position sensor is set at a position corresponding to the second set parameter value L2. When the return air pipe 10 When the starting end reaches the position of the second position sensor, it means that the length of the special-shaped section pipe section meets the requirements of the second set parameter value L2. The second position sensor transmits the signal to the control system. After receiving the signal, the control system makes the second position The second mold body 22 gradually moves away from the blank 26 .

The third position sensor is used to detect that the starting end of the return air pipe 10 reaches the third preset position to complete a cycle of forming processing of the return air pipe 10. At this time, it is equivalent to the termination end of the return air pipe 10 being located at the first preset position.

That is, along the transportation path of the return air pipe 10, according to the length design requirements of the return air pipe 10, a third position sensor is set at a position corresponding to the third set parameter value L3. When the starting end of the return air pipe 10 reaches the location of the third position sensor position, it means that the length of the circular cross-section pipe section meets the requirements of the third set parameter value L3. The third position sensor transmits a signal to the control system to complete a cycle of forming the return pipe 10.

In some embodiments of the present application, the first mold body 21 may also be an integral structure, and the first mold body 21 is disposed on the extrusion equipment. The ingot is divided into several metal flows through the pressure in the extrusion equipment (which can be a metal extruder), and enters the welding chamber through the shunt hole, where it is gathered in the welding chamber, and is heated in a high temperature, high pressure, and high vacuum environment. are welded together again, and finally flow out through the gap between the first mold body 21 and the mold core 23 to extrude to form a pipe body with a circular cross-section.

In some embodiments of the present application, as shown in Figures 4 and 6, in order to achieve higher molding accuracy of special-shaped cross-section pipe sections, a driving assembly 25 is connected to the mold core 23 for driving the mold core 23 to translate, so that the partial The mold core 23 enters the second mold cavity 224. At the same time, the mold core 23 has a molding part 231 and a recessed part 232. The molding part 231 cooperates with the first mold body 21 so that the first mold body 21 is extruded to form a circular cross-section. The pipe section, the recessed part 232 is nested with the protruding part 223 on the second mold body 22, so that the extrusion molding recess is more precise and easier to assemble with the capillary tube.

As shown in Figures 4 and 6, the entrance of the first mold cavity 213 is in the shape of an "eight", which can guide the blank 26 so that the blank 26 flows into the gap between the first mold body 21 and the mold core 23. .

During the use of the forming die 20 of the return air pipe 10 provided by the embodiment of the present application, the driving mechanism 24 is controlled by the main program of the extrusion equipment. When the length of the circular cross-section pipe section extruded by the first mold body 21 is determined, the driving mechanism 24. The third sub-mold body 221 is driven to move downward to close the mold with the fourth sub-mold body 222, and the circular cross-section pipe section extruded by the first mold body 21 is extruded, so that the extruded part of the pipe section After the length of the depression is determined, the driving mechanism 24 drives the third sub-mold body 221 to move upward and separate from the fourth sub-mold body 222, so that the circular cross-section pipe section extruded by the first mold body 21 is maintained.

In some embodiments of the present application, a fourth position sensor and a fifth position sensor are provided on the movement path of the driving mechanism 24;

The fourth position sensor is used to detect that the third sub-mold body 221 of the driving mechanism 24 is in a mold-locking position with the fourth sub-mold body 222 to ensure that the driving mechanism 24 drives the third sub-mold body 221 to move in place to avoid unqualified molding of the recessed structure. ;

The fifth position sensor is used to detect the driving mechanism 24. The third sub-mold body 221 is located at a position separated from the fourth sub-mold body 222, and has a set distance from the fourth sub-mold body 222 to ensure that the third sub-mold body 221 221 leaves the terminal end of the second formed pipe section.

In some embodiments of the present application, the above-mentioned first, second, third, fourth and fifth position sensors may include contact sensors and proximity sensors,

Contact sensors include micro switches. When the formed pipe section encounters the micro switch during movement, its internal contacts will act to output a signal.

Proximity sensors include electromagnetic sensors, photoelectric sensors, differential transformer sensors, eddy current sensors, capacitive sensors, reed switches, Hall sensors, etc. Preferably, in this embodiment, a photoelectric sensor is used, which can output a signal when the starting end of each formed pipe section approaches it to a set distance.

According to the molding die 20 of the embodiment of the present application, return air pipes 10 with different cross-sectional shapes can be continuously extruded to meet the production requirements for continuous extrusion of the return air pipe 10; at the same time, the size of the return air pipe 10 is stable and the cross-section consistency is good. The forming mold 20 Simple control and easy operation.

Referring to Figures 1 and 2 in detail, based on the above-mentioned forming mold 20, the forming method of the air return pipe 10 provided by this application includes the following steps:

Step S101: Control the blank 26 to enter the molding cavity, and control the mold core to squeeze the blank 26 so that the blank 26 passes through the first mold body, and obtains the first length value of the first molded pipe section formed by the first mold body;

That is, the blank 26 is transported to the gap between the first mold body 21 and the mold core 23 , and the mold core 23 is moved through a certain extrusion stroke in the first mold cavity 213 of the first mold body 21 to squeeze the blank 26 , forcing the blank 26 to produce directional plastic deformation and be extruded from the first mold body 21 , or continuously extruded from the first mold body 21 to the second mold body 22 .

Step S102: Determine that the first length value reaches the first set parameter value L1, control the second mold body 22 to squeeze part of the first formed pipe section, so that part of the first formed pipe section is formed into a second formed pipe section, and obtain the second formed pipe section. the second length value.

In some embodiments of the present application, as shown in Figure 2, in the step of determining that the first length value reaches the first set parameter value L1, if it is obtained that the starting end of the first formed pipe section reaches the first preset position, It can be determined that the first length value reaches the first set parameter value L1.

That is, as shown in FIG. 7 , the first position sensor detects the amount of material extruded from the first mold body 21 The position of the starting end of the first formed pipe section controls the second mold body 22 to start the extrusion work, and the second formed pipe section is continuously extruded at the rear end of the first formed pipe section.

Wherein, the first length value is the actual length of the first molded pipe section extruded through the first mold body 21. The cross-sectional shape of the first molded pipe section is circular. The position sensor ( Photoelectric sensor or micro switch), when the starting section of the extruded circular cross-section pipe section reaches the position of the position sensor, it is determined that the length of the circular cross-section pipe section meets the requirements.

Then, the driving mechanism 24 is started to be controlled so that the driving mechanism 24 pushes the third sub-mold body 221 to approach the fourth sub-mold body 222 and close the mold with the fourth sub-mold body 222 . In order to achieve a better forming effect of the forming pipe section, the lowering process of the driving mechanism 24 is carried out slowly, so that the gradient pipe section 13 is continuously formed on part of the first forming pipe section. After the third sub-mold body 221 and the fourth sub-mold body 222 are closed, After that, the forming of the special-shaped section pipe section begins, that is, the forming of the second formed pipe section.

Step S103: Determine that the second length value reaches the second set parameter value L2, and control the second mold body 22 to stop extrusion.

When detecting the second length value of the second molded pipe section extruded by the second mold body 22, it can be implemented in the following manner:

In the first embodiment, as shown in FIG. 2 , the second mold body 22 is controlled to extrude part of the first formed pipe section, so that part of the first formed pipe section is formed into a second formed pipe section, and the second length of the second formed pipe section is obtained. In the value step, if it is obtained that the starting end of the first formed pipe section reaches the second preset position, it is determined that the second formed pipe section reaches the second set parameter value L2;

Wherein, the first preset position and the second preset position are located in the conveying direction of the first forming pipe section, and the second preset position is located downstream of the first preset position.

That is, by using the second position sensor to detect that the starting end of the second molded pipe section extruded through the second mold body 22 reaches the position of the second position sensor, it can be determined when the second length value reaches the second set parameter value L2 , the second mold body 22 stops extruding, and the first mold body 21 continues to squeeze. At this time, the circular cross-section pipe structure formed by extrusion of the first mold body 21 is maintained, so that the rear end of the second molded pipe section Continuous extrusion forms a third formed pipe section.

As shown in Figure 8, along the movement path of the return air pipe 10, at least one position sensor is provided on the conveying path of the return air pipe 10. In this embodiment, the first position can be set at point a on the conveying path of the return air pipe 10. Sensor, point a corresponds to the starting end of the return air pipe 10; A second position sensor is provided at point b on the conveying path, and point b corresponds to the starting end of the second formed pipe section in the return air pipe 10; a third position sensor is provided at point c on the conveying path of the return air pipe 10, and point c corresponds to the return air pipe. The starting end of 10 also corresponds to the ending end of the return pipe 10 . By collecting the position information of each point, the forming length of each formed pipe section is determined.

It is also possible to set 6 position points on the outlet length of the formed pipe section along the movement path of the return air pipe 10 to obtain the corresponding 6 position signals, that is, the starting end of the first formed pipe section and the ending end of the first formed pipe section. , the starting end of the second formed pipe section, the ending end of the second formed pipe section, the starting end of the third formed pipe section, and the ending end of the third formed pipe section. By collecting the position information of each point, the forming length of each formed pipe section is determined.

In the second embodiment, in the step of controlling the second mold body 22 to squeeze part of the first formed pipe section, forming part of the first formed pipe section into a second formed pipe section, and obtaining the second length value of the second formed pipe section, if It is obtained that the second mold body is located at the mold closing position, the first forming pipe section is controlled to move at a preset speed for a preset time, and the second length value is obtained based on the preset speed and the preset time.

That is, the starting end of the first forming pipe section is detected by the first position sensor, and the driving mechanism 24 is controlled so that the driving mechanism 24 pushes the third sub-mold body 221 to approach the fourth sub-mold body 222 and connect with the fourth sub-mold body 222 . Specifically, mold closing 222 is performed by detecting the mold closing of the third sub-mold body 221 and the fourth sub-mold body 222 through the fourth position sensor provided on the movement path of the driving mechanism 24. At this time, the timer can be used to count to the set time. , the set time is determined according to the target length of the second forming pipe section and the feeding speed. After reaching the set time, the driving mechanism 24 returns to separate the third sub-mold body 221 from the fourth sub-mold body 222, which can also be obtained Second length value.

As shown in Figures 4 and 6, when entering the process of forming the second forming pipe section, there are two position signals on the moving path of the driving mechanism 24, that is, it is determined that the third sub-mold body 221 has penetrated into the position W1, and it is determined that the third sub-mold body 221 has penetrated into the position W1. The sub-module 221 exits to position W2. After it is determined that the third sub-mold body 221 gradually penetrates into the position W1 and starts timing, and after the time is determined according to the length requirement of the special-shaped section pipe section, the third sub-mold body 221 is controlled to gradually withdraw to the position W2, ending the second forming pipe section (special-shaped section pipe section). ) is formed into a circular cross-section pipe section.

Step S104: Control the third forming pipe section formed by the first mold to reach the third set parameter value L3;

In some embodiments of the present application, as shown in Figure 2, in the step of controlling the third forming pipe section formed by the first mold body 21 to reach the third set parameter value L3, if the first forming pipe is obtained When the starting end of the section reaches the third preset position, it is determined that the third formed pipe section reaches the third set parameter value L3; wherein, the first preset position and the third preset position are located in the conveying direction of the first formed pipe section, and the third preset position is located in the conveying direction of the first formed pipe section. The third preset position is located downstream of the first preset position.

That is, as shown in Figure 8, the third position sensor is used to detect that the starting end of the first forming pipe section has reached its position, and it is determined that a complete return pipe 10 has met the length required by the production drawing, and the first mold body 21 stops extrusion. When working, the formed return air pipe 10 is cut off, or after the formed return air pipe 10 is cut off, the first mold body 21 continues to work.

Wherein, the cross-sectional shape of the first mold body is different from the cross-sectional shape of the second mold body. The cross-section is the longitudinal cross-sectional shape of the first mold body and the second mold body, that is, the cross-sectional shape perpendicular to the axis direction of the return air pipe.

Among them, in each of the above steps, the first length value, the second length value and the third length value are the lengths actually measured during the processing of the corresponding formed pipe sections of the return pipe; the first setting parameter value L1, the second setting parameter value L1 The parameter value L2 and the third setting parameter value L3 are both the forming length of the corresponding forming pipe section, that is, the first setting parameter value L1, the second setting parameter value L2 and the third setting parameter value L3 are according to the design drawing requirements. , the target length of each formed pipe section in the return air pipe 10, that is, the reference length of each formed pipe section in the actual production process.

It can be understood that through this molding method, multiple pipe sections with different cross-sectional shapes can be continuously extruded, so that multiple pipe sections can be integrally formed, eliminating the solder joints between two adjacent pipe sections, and reducing the risk of leakage of the return pipe. It not only ensures the cross-section consistency of the return air pipe, but also meets the heat exchange and connection requirements of the return air pipe.

As shown in Figure 9, one aspect of the present application also provides an air return pipe 10, including an extruded first pipe section 11, a second pipe section 12, a gradual pipe section 13 and a third pipe section 14. The second pipe section 12 is located at the third pipe section. Between the first pipe section 11 and the third pipe section 14, both ends of the second pipe section 12 are connected to the first pipe section 11 and the third pipe section 14 respectively through the gradual pipe section 13. The second pipe section 12 is configured with a receiving part, and the receiving part faces the second pipe section. The central direction of 12 is recessed and extends along the axial direction of the second pipe section 12 .

Among them, the first pipe section 11 and the gradient pipe section 13 correspond to the starting end of the first shaped pipe section to the starting end of the second shaped pipe section, the second pipe section 12 corresponds to the second shaped pipe section, and the third pipe section 14 and the gradually changing pipe section 13 correspond to the starting end of the second shaped pipe section. The terminating end of the second formed pipe section and the terminating end of the third formed pipe section.

The first pipe section 11 and the third pipe section 14 are adapted to be connected to connecting pipes provided in the evaporator and the compressor respectively, and the second pipe section 12 is formed with a receiving portion for embedding the capillary tube.

Equivalently, the first pipe section 11 and the third pipe section 14 are used to connect the connecting pipes provided in the evaporator and the compressor respectively; the capillary tube is wrapped in the accommodating part, which can increase the contact area between the capillary tube and the return pipe 10; all pipe sections are integrated Forming, there are no welding spots between two adjacent pipe sections, which can ensure the sealing of the entire return air pipe 10 and effectively prevent leakage of the return air pipe 10.

It can be understood that the air return pipe 10 provided by the present application has all the pipe sections integrally formed, and a receiving portion for embedding the capillary tube is formed in the second pipe section 12, which can not only increase the contact area between the air return pipe 10 and the capillary tube, but also can increase the contact area between the air return pipe 10 and the capillary tube. In order to improve the heat exchange efficiency and facilitate the connection between the return pipe 10 and the connecting pipe, the solder joints between two adjacent pipe sections are eliminated, and the risk of leakage of the return pipe 10 is reduced.

Currently, the heat exchange tubes used in the refrigeration system of refrigerators or freezers are generally aluminum return pipes 10 and copper capillary tubes, where the aluminum return pipes 10 have a circular cross-section. The return air pipe 10 is fixed to the capillary tube through aluminum foil, heat shrink tube, etc. After being fixed in this way, there is linear contact between the return air pipe 10 and the capillary tube, the contact area is small, and the thermal efficiency is low.

For this reason, in the related art, the length of the return air pipe 10 is extended to increase the contact area between the return air pipe 10 and the capillary tube, thereby improving the heat exchange efficiency. However, this significantly increases the material cost and manufacturing cost of the return air pipe 10, and increases the system cost. Reduced market competitiveness.

For this reason, in some related technologies, the capillary tube is fully or partially buried in the return air pipe 10 to increase the contact area between the return air pipe 10 and the capillary tube, thereby improving the heat exchange efficiency. Since the two ends of the return pipe 10 with the special-shaped cross-section structure cannot be directly connected to the evaporator and the compressor, in the related art, circular cross-section connecting pipes are welded to the two ends of the special-shaped cross-section structure and then connected to the evaporator and the compressor.

The above arrangement adds two solder joints (brazed joints or resistance welding points) to the connection between the return air pipe 10 and the evaporator and compressor. At the same time, it increases the risk of leakage of the return air pipe 10 in the foam layer and reduces the risk of the system. reliability.

To this end, this application provides an air return pipe 10. The initial part of the air return pipe 10 is a first pipe section with a circular cross-section structure, the middle part is a second pipe section with a special-shaped cross-section structure, and the last part is a first pipe section with a circular cross-section structure. That is, the cross-sectional shape of the return air pipe 10 changes from a circular shape to a special shape, and then from a special shape to a circular shape. This structure can not only increase the contact area between the return air pipe 10 and the capillary tube, improve the heat exchange efficiency, but also facilitate the connection between the return air pipe 10 and the connecting pipe, thereby eliminating the solder joints existing on the return air pipe 10 and reducing system leakage. risks and improve the reliability of the system. Moreover, through this structural arrangement, the material cost and manufacturing cost of the return air pipe 10 are reduced, and the market competitiveness of the pipe body is improved. competitiveness.

Finally, it should be noted that the above embodiments are only used to illustrate the present application, but not to limit the present application. Although the present application has been described in detail with reference to the embodiments, those of ordinary skill in the art should understand that various combinations, modifications or equivalent substitutions of the technical solutions of the present application do not depart from the spirit and scope of the technical solutions of the present application and should all be covered within the scope of the claims of this application.

Claims

A method for forming a return air pipe, including:

Control the blank to enter the molding cavity, and control the mold core to squeeze the blank so that the blank passes through the first mold body, and obtain the first length value of the first forming pipe section formed by the first mold body;

Determine that the first length value reaches the first set parameter value, control the second mold body to extrude part of the first formed pipe section, so that the part of the first formed pipe section is formed into a second formed pipe section, and obtain the second formed pipe section. second length value;

Determine that the second length value reaches the second set parameter value, and control the second mold body to stop extrusion;

Controlling the third forming pipe section formed by the first mold body to reach a third set parameter value;

Wherein, the cross-sectional shape of the first mold body is different from the cross-sectional shape of the second mold body.
The method for forming an air return pipe according to claim 1, wherein:

In the step of determining that the first length value reaches the first set parameter value,

When it is obtained that the starting end of the first formed pipe section reaches the first preset position, it is determined that the first length value reaches the first set parameter value.
The method of forming a return air pipe according to claim 2, wherein the second mold body is controlled to squeeze a portion of the first formed pipe section to form the partial first formed pipe section into a second formed pipe section, and obtain the second formed pipe section. In the step for the second length value of the pipe segment,

After obtaining that the starting end of the first formed pipe section reaches the second preset position, it is determined that the second formed pipe section reaches the second set parameter value;

Wherein, the first preset position and the second preset position are located in the conveying direction of the first forming pipe section, and the second preset position is located downstream of the first preset position.
The method of forming a return air duct according to claim 2, wherein in the step of controlling the third forming pipe section formed by the first mold body to reach a third set parameter value,

After obtaining that the starting end of the first formed pipe section reaches the third preset position, it is determined that the third formed pipe section reaches the third set parameter value;

Wherein, the first preset position and the third preset position are located in the conveying direction of the first forming pipe section, and the third preset position is located downstream of the first preset position.
The method for forming an air return pipe according to claim 1, wherein:

In the step of controlling the second mold body to extrude part of the first formed pipe section, forming the part of the first formed pipe section into a second formed pipe section, and obtaining the second length value of the second formed pipe section,

It is obtained that the second mold body is located at the mold closing position, the first forming pipe section is controlled to move at a preset speed for a preset time, and the second length value is obtained based on the preset speed and the preset time.
A molding mold used to perform the molding method of the return air duct according to any one of claims 1 to 5, including a mold core, a first mold body and a second mold body, the mold core and the first mold body A molding cavity is formed between them;

The second mold body is located on the discharge end side of the first mold body, and the second mold body includes a third sub-mold body and a fourth sub-mold body located on one side of the third sub-mold body. , the third sub-mold body or the fourth sub-mold body is provided with a protruding portion, and the protruding portion faces the center of the second mold body.
The molding mold according to claim 6, wherein at least one of a first position sensor, a second position sensor and a third position sensor is provided on a side of the second mold body facing away from the first mold body;

The first position sensor is used to detect that the starting end of the first formed pipe section reaches a first preset position; the second position sensor is used to detect that the starting end of the first formed pipe section reaches a second preset position; The third position sensor is used to detect that the starting end of the first formed pipe section reaches a third preset position.
The molding mold according to claim 6, wherein the protruding portion is provided on the third sub-mold body, and a driving mechanism is connected to the third sub-mold body; the driving mechanism causes the third sub-mold body to The three sub-molds are specifically adapted to switch between the first position and the second position;

In the first position, the third sub-mold body is separated from the fourth sub-mold body and has a set distance from the fourth sub-mold body;

In the second position, the third sub-mold body is molded together with the fourth sub-mold body.
The molding mold according to claim 8, wherein a fourth position sensor and a fifth position sensor are provided on the movement path of the driving mechanism;

The fourth position sensor is used to detect that the third sub-mold body is located in a mold-locking position with the fourth sub-mold body;

The fifth position sensor is used to detect that the third sub-mold body is located at a position separated from the fourth sub-mold body.
An air return pipe includes an extruded first pipe section, a second pipe section and a third pipe section, wherein the second pipe section is located between the first pipe section and the second pipe section, and the second pipe section A receiving portion is configured which is recessed toward the center of the second pipe section and extends along the axial direction of the second pipe section.