Automobile sound absorbing cotton welding device

Abstract

The present application relates to sound absorbing cotton welding technical field, disclose a kind of automobile sound absorbing cotton welding device, including welding head and cooling structure, cooling structure includes cooling cavity, cooling pipe and air cooling structure, cooling pipe is provided with the protective cooling structure of the cooling liquid spray into cooling cavity, cooling liquid can be taken away from cooling cavity by air cooling structure, in this welding device, when temperature is less than first preset temperature, only by driving cooling liquid to flow in cooling pipe, drive air cooling structure, can simultaneously realize indirect water cooling and air cooling, reduce the temperature on the end of welding head far away from welding surface, when temperature is equal to or greater than first preset temperature, part of cooling liquid is directly contacted with welding head and cooled by protective cooling structure, and heat-exchanged cooling liquid can be quickly taken away by air cooling structure, by greatly reducing the possibility of cooling liquid and high-temperature welding head contact, to ensure timely reduce the temperature on the end of welding head far away from welding surface while prolonging the service life of welding head.

Description

Technical Field

[0001] This invention relates to the field of sound-absorbing cotton welding technology, and more particularly to a welding device for automotive sound-absorbing cotton. Background Technology

[0002] Cars generate various noises, such as wind noise, while driving. To improve driving comfort and meet users' demand for quietness, sound-absorbing cotton is currently installed inside the vehicle to reduce noise.

[0003] Chinese Patent Application No. 202121097043.8 discloses a welding device for sound-absorbing cotton in an automotive trunk assembly, including a support platform for stacking automotive trunk substrate and automotive sound-absorbing cotton, a pressing claw for pressing the automotive sound-absorbing cotton and automotive trunk substrate onto the support platform, and an ultrasonic welding gun for welding the sound-absorbing cotton and automotive trunk substrate together, and also includes a displacement mechanism for driving the ultrasonic welding gun to move.

[0004] In the above scheme, the sound-absorbing cotton and the substrate are welded by an ultrasonic welding gun. In the prior art, ultrasonic welding converts electrical energy into high-frequency alternating current signals through an ultrasonic generator. The high-frequency electrical signals are converted into high-frequency mechanical motion through a transducer. The mechanical motion is then transmitted to the welding head through an amplitude transformer. The welding head transmits the received vibration energy to the joint of the workpiece to be welded. The vibration energy is converted into heat energy through friction, causing the sound-absorbing panel and the substrate to melt and weld.

[0005] In ultrasonic welding, the heating point is usually located on the welding surface between the sound-absorbing cotton and the substrate. However, since the welding head is generally made of a material with good thermal conductivity, the heat from the end of the welding head near the welding surface will be conducted to the end away from the welding surface. The end of the welding head away from the welding surface is close to the amplitude transformer and transducer. The transducer itself generates heat, which, combined with the heat transferred from the welding head, causes the heat around the transducer to not dissipate in time. This leads to depolarization of the piezoelectric ceramic, a decrease in output amplitude, and damage to the transducer. Therefore, a cooling structure is required.

[0006] The common cooling structure in existing technology is to drill holes inside the welding head to form cooling channels, through which the coolant flows and directly contacts the welding head for heat exchange and cooling. However, the temperature of the coolant is relatively low, and the high-temperature welding head will generate internal stress due to uneven thermal expansion and contraction when directly cooled. Long-term use of this cooling method may lead to welding head deformation, cracks, or cracking and peeling of the anti-stick coating on the outside of the welding head, thus shortening the service life of the welding head. Summary of the Invention

[0007] This invention addresses the shortcomings of existing technologies where direct contact between coolant and high-temperature welding head for heat exchange can lead to welding head deformation, cracking, or cracking and peeling of the anti-stick coating on the outside of the welding head. It provides an automotive sound-absorbing cotton welding device that can promptly reduce the temperature at the end of the welding head away from the welding surface and extend the service life of the welding head.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0009] A welding device for automotive sound-absorbing cotton includes a welding head and a cooling structure disposed at the end of the welding head away from the welding surface. The cooling structure includes a cooling cavity disposed inside the welding head, a cooling pipe disposed inside the cooling cavity for supplying coolant, and an air-cooling structure disposed between the cooling pipe and the cooling cavity for carrying away hot air inside the cooling cavity and replenishing external cold air. The opening and closing of the air-cooling structure is controlled by the flow or stillness of coolant in the cooling pipe. The cooling pipe is provided with a protective cooling structure that drives coolant to be directly sprayed into the cooling cavity for contact cooling when the temperature of the end of the welding head away from the welding surface is equal to or greater than a first preset temperature. The coolant sprayed into the cooling cavity can be carried away from the cooling cavity by the air-cooling structure.

[0010] Using the above scheme, when the temperature is below the first preset temperature, the coolant is driven to flow in the cooling pipes by a water pump. Combined with the air-cooling structure, indirect water cooling and air cooling can be achieved simultaneously, promptly reducing the temperature at the end of the welding head furthest from the welding surface. However, in actual applications, special circumstances may still occur, causing the temperature at the end of the welding head furthest from the welding surface to continuously rise to equal or greater than the first preset temperature. In this case, the protective cooling structure allows a portion of the coolant to flow from the cooling pipes into the cooling chamber and directly contact the welding head for rapid cooling. The majority of the remaining coolant continues to flow in the cooling pipes to the outlet, and indirect water cooling and air cooling remain effective. Furthermore, the coolant that has undergone heat exchange in the cooling chamber can be quickly carried away by the air-cooling structure. Once the temperature drops below the first preset temperature, the protective cooling structure stops injecting coolant into the cooling chamber. In summary, under normal circumstances, indirect water cooling and air cooling can be achieved simply by driving the coolant to flow in the cooling pipes. Only under special circumstances will the coolant come into contact with the welding head, which greatly reduces the possibility of the coolant coming into contact with the high-temperature welding head. This ensures that the temperature of the end of the welding head away from the welding surface is reduced in time, while extending the service life of the welding head.

[0011] As a preferred embodiment, the air-cooled structure includes a Venturi channel with an inner diameter that gradually decreases along the flow direction of the coolant, a connecting pipe with one end connected to the Venturi channel and the other end in clearance fit with the bottom surface of the cooling chamber, and an air inlet on the welding head that connects the cooling chamber to the outside.

[0012] Using the above scheme, when the coolant flows through the Venturi channel, the flow rate of the coolant increases due to the narrowing of the inner diameter, which generates a negative pressure in the Venturi channel. Hot air or coolant is drawn into the cooling chamber through the connecting pipe. The hot air or coolant drawn into the Venturi channel flows unidirectionally along with the coolant flowing in the cooling pipe and is carried out to the outside of the welding head. After the hot air is drawn away, the air pressure in the cooling chamber decreases. Cold air from the outside is drawn into the cooling chamber through the air inlet to replenish the pressure and generate air flow in the cooling chamber, further accelerating heat exchange and cooling.

[0013] Preferably, the protective cooling structure includes an outlet pipe provided on the cooling pipe to connect the cooling pipe and the cooling chamber, and a temperature control opening and closing structure provided between the cooling pipe and the cooling chamber, which opens the outlet pipe when the temperature of the end of the welding head away from the welding surface is equal to or greater than a first preset temperature, and controls the outlet pipe to close when the temperature is less than the first preset temperature.

[0014] Using the above scheme, when the temperature of the end of the welding head away from the welding surface is equal to or greater than the first preset temperature, the outlet pipe is opened by the temperature control opening and closing structure, and a portion of the coolant in the cooling pipe flows into the cooling chamber from the outlet pipe; when the temperature is lower than the first preset temperature, the outlet pipe is closed by the temperature control opening and closing structure, and the injection of coolant into the cooling chamber stops.

[0015] Preferably, the temperature control opening and closing structure includes a mounting block fixedly installed on the outer wall of the cooling pipe, a sliding cavity installed inside the mounting block and connected to the end of the outlet pipe away from the cooling pipe and the cooling chamber, and a stop block installed in the sliding cavity that can block or open the outlet pipe by reciprocating radially along the outlet pipe. The movement of the stop block is controlled by a memory spring. A heat-conducting rod is installed in the cooling chamber with its two ends connected to the top of the cooling chamber and the memory spring respectively for heat conduction.

[0016] Using the above scheme, the deformation temperature of the memory spring is the first preset temperature. When the temperature at the end of the welding head away from the welding surface reaches the first preset temperature, the memory spring is heated through the heat-conducting rod and rises to reach the deformation temperature. The memory spring contracts and deforms, driving the stop block to rise and opening the liquid outlet pipe. Conversely, when the temperature is lower than the first preset temperature, the temperature of the memory spring decreases accordingly, the memory spring unfolds and returns to its original state, driving the stop block to fall and closing the liquid outlet pipe.

[0017] Preferably, the mounting block is provided with a liquid outlet channel that connects the sliding cavity and the cooling cavity, and the liquid outlet channel is equipped with a spraying structure that drives the coolant flowing out of the liquid outlet pipe to spray into the cooling cavity to increase the contact area between the coolant and the cooling cavity.

[0018] With the above-described solution, the coolant, after being sprayed from the outlet pipe, falls directly to the bottom of the cooling chamber under gravity, resulting in minimal or no contact with the top and inner ring walls of the cooling chamber. Consequently, the cooling effect on the portion of the welding head located above the bottom surface of the cooling chamber is not significant. Therefore, a spraying structure is designed to allow the coolant to be sprayed into the cooling chamber from different directions, increasing the likelihood and area of ​​contact between the coolant and the top and inner ring walls of the cooling chamber, and rapidly reducing the temperature of the end of the welding head furthest from the welding surface.

[0019] Preferably, the spraying structure includes a rotating shaft with one end sealed and rotatably connected to the liquid outlet channel and the other end located outside the mounting block, a spray pipe protruding outward on the outer ring wall of the rotating shaft outside the mounting block, and a liquid passage provided inside the rotating shaft to connect the liquid outlet channel and the spray pipe. Several spray pipes are evenly spaced around the axial direction of the rotating shaft, and the liquid sprayed from the spray pipes drives the rotating shaft to rotate.

[0020] Using the above scheme, the liquid flowing from the outlet pipe passes through the outlet channel and the liquid passage before being sprayed out through the spray pipe. The direction of the coolant sprayed from the spray pipe is at an angle to the radial direction of the rotating shaft, and the rapidly sprayed coolant drives the shaft to rotate. The coolant is rapidly sprayed from the spray pipe and continuously rotates with the shaft, allowing it to be sprayed and flung to directly contact the top of the cooling chamber and the inner ring wall for cooling. Under gravity, it falls and collects at the bottom of the cooling chamber, where it is carried away by the air-cooling structure.

[0021] Preferably, the cooling chamber is provided with an auxiliary cooling structure that drives the inner wall of the cooling chamber and the cooling pipe to contact and conduct heat when the temperature of the end of the welding head away from the welding surface reaches a second preset temperature. The second preset temperature is lower than the first preset temperature.

[0022] In order to minimize the probability of coolant spraying into the cooling chamber and directly contacting the welding head, an auxiliary cooling structure is set in the cooling chamber. When the temperature of the welding head rises to the second preset temperature, the auxiliary cooling structure increases the cooling capacity and efficiency of the welding head, thus delaying or preventing the temperature of the welding head from rising further.

[0023] Preferably, the auxiliary cooling structure includes a memory metal rod with one end fixedly connected to the inner wall of the cooling cavity and the other end suspended in the air. When the temperature is lower than the second preset temperature, the suspended end of the memory metal rod is detached from the cooling pipe; when the temperature is equal to or greater than the second preset temperature, the suspended end of the memory metal rod is attached to the cooling pipe.

[0024] Using the above scheme, the deformation temperature of the shape memory metal rod is the second preset temperature. When the temperature at the end of the welding head furthest from the welding surface reaches the second preset temperature, the shape memory metal rod heats up to reach the deformation temperature. The shape memory metal rod unfolds and deforms until the suspended end abuts against the outer wall of the cooling pipe. Heat conduction between the welding head and the cooling pipe is achieved through the shape memory metal rod. Compared with using air for heat exchange, the heat conduction efficiency is greatly improved, and the cooling efficiency is greatly improved. Conversely, when the temperature is lower than the second preset temperature, the temperature of the shape memory metal rod decreases accordingly. The shape memory metal rod retracts and returns to its original position until the suspended end separates from the outer wall of the cooling pipe. This prevents the welding head from cooling down too quickly, which would affect the temperature of the welding head on the welding surface and increase the time and energy consumption required for it to heat up to the target temperature.

[0025] Preferably, several shape memory metal rods are provided at intervals along the axial direction of the welding head and around the axial direction of the welding head.

[0026] Using the above scheme, the shape memory metal rods are spaced apart along the axial direction. Temperature is conducted from the end of the welding head closest to the welding surface to the end furthest away. The number of deformed shape memory metal rods can be automatically adjusted based on the welding head's temperature rise and position, thus controlling the cooling rate. The shape memory metal rods are spaced apart along the welding head's axial direction to increase the contact area for rapid heat conduction and reduce the temperature of the welding head at that location on the plane.

[0027] Preferably, the cooling pipe is made of a metal material with good thermal conductivity.

[0028] Using the above scheme, the cooling pipe is made of metal, and after being connected to the welding head by a shape memory metal rod, the heat conduction and cooling are further accelerated.

[0029] This invention, by employing the above technical solutions, achieves significant technical effects: When the temperature at the end of the welding head furthest from the welding surface is lower than the second preset temperature, indirect water cooling and air cooling can be simultaneously achieved by simply driving the coolant to flow in the cooling pipe, promptly reducing the temperature at the end of the welding head furthest from the welding surface. Furthermore, this cooling method is relatively gentle, achieving cooling at the end of the welding head furthest from the welding surface while minimizing the impact on the temperature rise at the end of the welding head in contact with the welding surface. When the temperature at the end of the welding head furthest from the welding surface is equal to or greater than the second preset temperature, the memory metal rod unfolds, allowing the welding head and cooling pipe to connect and conduct heat through the memory metal rod, accelerating the cooling speed and efficiency of the welding head. When the temperature at the end of the welding head furthest from the welding surface is equal to or greater than the first preset temperature, the memory spring retracts, causing the stop block to rise and open the outlet pipe. A portion of the coolant is sprayed from the spray pipe and rotates with the shaft, spraying into the cooling chamber to directly contact the welding head for rapid cooling. The cooled coolant after heat exchange can be quickly absorbed through the connecting pipe. Only under special circumstances will the coolant come into contact with the welding head, greatly reducing the possibility of the coolant coming into contact with the high-temperature welding head, ensuring that the temperature on the end of the welding head away from the welding surface is reduced in time while extending the service life of the welding head. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of a welding device for automotive sound-absorbing cotton in one embodiment;

[0031] Figure 2 This is a top view of the welding head and cooling structure in an automotive sound-absorbing cotton welding device according to an embodiment;

[0032] Figure 3 yes Figure 2 Sectional view at point AA;

[0033] Figure 4 yes Figure 3 Enlarged view of point B in the image;

[0034] Figure 5 yes Figure 3 Enlarged view of point C in the image;

[0035] Figure 6 This is a partial enlarged view of the auxiliary cooling structure and the protective cooling structure in an automotive sound-absorbing cotton welding device in the embodiment when they are in effect;

[0036] Figure 7 This is an exploded view of the welding head and cooling structure in an automotive sound-absorbing cotton welding device according to an embodiment;

[0037] Figure 8 yes Figure 7 Enlarged view of point D in the image.

[0038] The parts referred to by the numbers in the above attached diagrams are as follows: 1. Welding head; 2. Cooling chamber; 3. Cooling pipe; 301. Liquid inlet; 302. Liquid outlet; 4. Venturi channel; 5. Connecting pipe; 6. Air inlet; 7. Liquid outlet pipe; 8. Mounting block; 9. Sliding chamber; 10. Heat-conducting block; 11. Baffle; 12. Memory spring; 13. Heat-conducting rod; 14. Rotating shaft; 15. Liquid spray pipe; 16. Liquid passage; 17. Memory metal rod; 18. Worktable; 19. Robotic arm; 20. Liquid outlet channel. Detailed Implementation

[0039] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0040] Example

[0041] A welding device for automotive sound-absorbing cotton, as shown in the reference. Figures 1 to 8The system includes a worktable 18 for stacking substrates and sound-absorbing cotton, a robotic arm 19 mounted on the worktable 18, and an ultrasonic welding gun at the end of the robotic arm 19. The ultrasonic welding gun includes an ultrasonic generator that converts electrical energy into a high-frequency alternating current signal, a transducer that converts the high-frequency electrical signal into high-frequency mechanical motion, and an amplitude transformer that transmits the mechanical motion to the welding head 1. The welding head 1 transmits the received vibration energy to the joint between the sound-absorbing cotton and the substrate. The vibration energy is converted into heat energy through friction, causing the sound-absorbing cotton and the substrate to melt and weld together to form a weld surface. All the above structures, connection methods, working methods, and principles are existing technologies and have not been improved; therefore, they will not be described in detail here.

[0042] A cooling structure is provided at the end of the welding head 1 away from the welding surface. The cooling structure includes a cooling cavity 2 located inside the end of the welding head 1 away from the welding surface. The side of the cooling cavity 2 closest to the welding surface is the bottom surface of the cooling cavity 2, and the side of the cooling cavity 2 away from the welding surface is the top surface of the cooling cavity 2. A cooling pipe 3 is provided inside the cooling cavity 2. The inlet 301 and outlet 302 of the cooling pipe 3 extend out of the welding head 1 and are located outside the welding head 1. The inlet 301 and outlet 302 are connected to a water tank and a water pump through water pipes. The water pump drives the coolant to flow unidirectionally within the cooling pipe 3. The water tank, water pipes, water pump, and the connection and driving method between the three and the cooling pipe 3 are all existing technologies and are not shown in the figure, nor will they be described in detail here. In this embodiment, the portion of the cooling pipe 3 located inside the cooling cavity 2 is U-shaped and does not directly contact the cooling cavity 2. The cooling pipe 3 is made of a metal material with good thermal conductivity. In this embodiment, copper can be used, and the coolant in this embodiment is cooling water.

[0043] The cooling pipe 3 has a variable diameter section whose inner diameter gradually decreases along the flow direction of the coolant. This variable diameter section is the Venturi channel 4. In this embodiment, the Venturi channel 4 is located near the bottom surface of the cooling pipe 3, close to the cooling chamber 2. A connecting pipe 5 is installed inside the cooling chamber 2. One end of the connecting pipe 5 is located above and communicates with the Venturi channel 4, while the other end is in clearance fit with the bottom surface of the cooling chamber 2. The gap between the connecting pipe 5 and the bottom surface of the cooling chamber 2 ensures that air or coolant in the cooling chamber 2 can enter the Venturi channel 4 through the connecting pipe 5. The bottom surface of the cooling chamber 2 can be set as a flat surface or a concave arc surface. If it is set as a concave arc surface, the end of the connecting pipe 5 away from the Venturi channel 4 is in clearance fit with the lowest point of the arc surface. The welding head 1 is provided with an air inlet 6 that connects the cooling chamber 2 and the outside of the welding head 1, and the air inlet 6 is located near the top of the cooling chamber 2. A filter screen is installed inside the air inlet 6 to prevent external impurities from entering the cooling chamber 2 with the cold air. In actual use, the air temperature near the welding head 1 will also rise. Therefore, an air intake pipe can be connected to the air inlet 6 to draw in cool air from a distance to ensure a cooling effect. The air intake pipe, filter screen, and the installation and connection method of the filter screen and air intake pipe are all existing technologies and are not shown in the figure, so they will not be described in detail here.

[0044] A mounting block 8 is provided on the outer ring wall of the cooling pipe 3 near its liquid inlet 301. A sliding cavity 9 is provided inside the mounting block 8. A liquid outlet pipe 7 is provided on the cooling pipe 3, connecting the cooling pipe 3 to the sliding cavity 9. A stop block 11 is provided within the sliding cavity 9, moving radially back and forth along the liquid outlet pipe 7. When the stop block 11 descends, it blocks the liquid outlet pipe 7; when the stop block 11 rises, it connects the liquid outlet pipe 7 to the sliding cavity 9. A liquid outlet channel 20 is provided on the side of the mounting block 8 away from the cooling pipe 3, connecting the sliding cavity 9 and the cooling cavity 2. The liquid outlet channel 20 is concentrically arranged with the liquid outlet pipe 7.

[0045] A heat-conducting block 10 is fixedly installed on the side of the sliding cavity 9 near the top of the cooling cavity 2. A memory spring 12 is installed inside the sliding cavity 9 between the heat-conducting block 10 and the stop block 11, along the moving direction of the stop block 11. The two ends of the memory spring 12 are fixedly connected to the heat-conducting block 10 and the stop block 11, respectively. A heat-conducting rod 13 is installed inside the cooling cavity 2, with one end fixedly connected to the top of the cooling cavity 2 and the other end sealed and inserted into the sliding cavity 9 and fixedly connected to the heat-conducting block 10. In this embodiment, since the surface temperature of the transducer should generally be controlled below 80℃ during normal operation, otherwise there may be a risk of damage, the memory spring 12 is made of CuZnAl memory alloy. It utilizes the two-way memory effect of shape memory alloys, with a deformation temperature (phase transition temperature) of 65~70℃. It is in an extended state under normal conditions and deforms and contracts when the temperature reaches the deformation temperature. The deformation temperature of the memory spring 12 is the first preset temperature. The heat-conducting block 10 and the heat-conducting rod 13 are made of a metal material with good thermal conductivity; copper can be selected in this embodiment.

[0046] A rotating shaft 14 is concentrically sealed and rotatably connected within the liquid outlet channel 20, with one end of the rotating shaft 14 away from the liquid outlet pipe 7 located outside the mounting block 8. A spray pipe 15 protrudes outward from the outer ring wall of the rotating shaft 14 outside the mounting block 8. A liquid passage 16 is provided within the rotating shaft 14 to connect the liquid outlet channel 20 and the spray pipe 15. In this embodiment, the spray pipe 15 includes a pipe body and a nozzle. The pipe body of the spray pipe 15 is arranged radially along the rotating shaft 14, and the nozzle of the spray pipe 15 is perpendicularly connected to its pipe body, so that the liquid sprayed from the spray pipe 15 can drive the rotating shaft 14 to rotate. Several spray pipes 15 are evenly spaced around the axial direction of the rotating shaft 14; in this embodiment, three are provided.

[0047] A shape memory metal rod 17 is installed inside the cooling chamber 2, with one end fixedly connected to the inner annular wall of the cooling chamber 2 and the other end suspended. In this embodiment, the shape memory metal rod 17 is made of NiTi alloy and has a two-way shape memory effect. Its deformation temperature is about 40°C. Under normal conditions, it is in a coiled state and deforms and unfolds when the temperature reaches the deformation temperature. The deformation temperature of the shape memory metal rod 17 is the second preset temperature. Seven shape memory metal rods 17 are evenly spaced along the axial direction of the welding head 1, and the above seven shape memory metal rods 17 are evenly spaced in two sets around the axial direction of the welding head 1.

[0048] When welding begins, the temperature of the end of the welding head 1 furthest from the welding surface is lower than the second preset temperature. The water pump is turned on to drive the coolant into the cooling pipe 3 from the inlet 301 and out from the outlet 302. The coolant flowing unidirectionally in the cooling pipe 3 exchanges heat with the air in the cooling chamber 2 to cool it down. The cooled air then comes into contact with the welding head 1 to cool it down. At the same time, the flowing coolant draws the hot air in the cooling chamber 2 into the Venturi channel 4 through the connecting pipe 5 and is carried away from the cooling chamber 2 along with the coolant. The cold air from outside is replenished into the cooling chamber 2 and forms an airflow, further reducing the temperature of the welding head 1. The above cooling method is relatively gentle, achieving cooling of the end of the welding head 1 furthest from the welding surface while having little impact on the temperature rise of the end of the welding head 1 in contact with the welding surface.

[0049] When the temperature at the end of the welding head 1 furthest from the welding surface is equal to or greater than the second preset temperature, the memory metal rod 17 unfolds, allowing the welding head 1 and the cooling pipe 3 to connect and conduct heat through the memory metal rod 17. This quickly transfers the heat from the welding head 1 to the cooling pipe 3, where it is carried away by the coolant, thus accelerating the cooling speed and efficiency and delaying or preventing the temperature at the end of the welding head 1 furthest from the welding surface from continuing to rise.

[0050] When the temperature at the end of the welding head 1 furthest from the welding surface is equal to or greater than the first preset temperature, the memory spring 12 retracts, causing the stop block 11 to rise and open the outlet pipe 7. A portion of the coolant is sprayed out from the spray pipe 15, causing the rotating shaft 14 to rotate. This allows the coolant to be sprayed and flung to directly contact the top of the cooling chamber 2 and the inner ring wall for rapid cooling, preventing overheating. After heat exchange, the coolant falls and collects at the bottom of the cooling chamber 2 under gravity. Most of the coolant that is not sprayed out from the spray pipe 15 continues to flow unidirectionally within the cooling pipe 3, and indirect water cooling and air cooling remain effective. Therefore, the coolant collected at the bottom of the cooling chamber 2 can be quickly sucked away through the connecting pipe 5.

[0051] When the temperature at the end of the welding head 1 away from the welding surface drops below the first preset temperature, the memory spring 12 unfolds to drive the stop block 11 to descend and block the liquid outlet pipe 7, stopping the spraying of liquid into the cooling chamber 2; when the temperature drops below the second preset temperature, the memory metal rod 17 retracts and disengages from the cooling pipe 3.

[0052] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A welding device for automobile sound absorbing cotton, comprising a welding head (1) and a cooling structure arranged in the welding head (1) away from the welding surface, characterized in that: The cooling structure comprises a cooling cavity (2) arranged in the welding head (1), a cooling pipe (3) arranged in the cooling cavity (2) for flowing cooling liquid, and a wind cooling structure arranged between the cooling pipe (3) and the cooling cavity (2) for taking away the hot air in the cooling cavity (2) and supplementing the outside cold air. The opening and closing of the wind cooling structure is controlled by the flowing or static of the cooling liquid in the cooling pipe (3). The cooling pipe (3) is provided with a protective cooling structure for directly spraying the cooling liquid into the cooling cavity (2) for contact cooling when the temperature of the end of the welding head (1) away from the welding surface is equal to or greater than the first preset temperature. The cooling liquid sprayed into the cooling cavity (2) can be taken away from the cooling cavity (2) by the wind cooling structure. The wind cooling structure comprises a Venturi flow channel (4) arranged on the cooling pipe (3) and gradually reducing in inner diameter along the flowing direction of the cooling liquid, a connecting pipe (5) in communication with one end of the Venturi flow channel (4) and in gap cooperation with the bottom surface of the cooling cavity (2), and an air inlet (6) arranged on the welding head (1) for connecting the cooling cavity (2) with the outside. The protective cooling structure comprises a liquid outlet pipe (7) arranged on the cooling pipe (3) for connecting the cooling pipe (3) and the cooling cavity (2), and a temperature control opening and closing structure arranged between the cooling pipe (3) and the cooling cavity (2) for opening the liquid outlet pipe (7) when the temperature of the end of the welding head (1) away from the welding surface is equal to or greater than the first preset temperature and closing the liquid outlet pipe (7) when the temperature is less than the first preset temperature. The temperature control opening and closing structure comprises a mounting block (8) fixedly arranged on the outer wall of the cooling pipe (3), a sliding cavity (9) arranged in the mounting block (8) and in communication with the liquid outlet pipe (7) away from the cooling pipe (3) and the cooling cavity (2), and a stop block (11) arranged in the sliding cavity (9) and reciprocally moving along the radial direction of the liquid outlet pipe (7) for blocking or opening the liquid outlet pipe (7). The movement of the stop block (11) is controlled by a memory spring (12). The cooling cavity (2) is provided with a heat conduction rod (13) having two ends connected with the top of the cooling cavity (2) and the memory spring (12) for heat conduction. The mounting block (8) is provided with a liquid outlet channel (20) connecting the sliding cavity (9) and the cooling cavity (2). The liquid outlet channel (20) is provided with a spraying structure for spraying the cooling liquid flowing out of the liquid outlet pipe (7) in the cooling cavity (2) to increase the contact area of the cooling liquid with the cooling cavity (2).

2. The welding device for automobile sound absorbing cotton according to claim 1, characterized in that: The spraying structure comprises a rotating shaft (14) having one end sealingly and rotatably connected with the liquid outlet channel (20) and the other end located outside the mounting block (8), a liquid spraying pipe (15) outwardly protruding on the outer ring wall of the rotating shaft (14) outside the mounting block (8), and a liquid passing channel (16) arranged in the rotating shaft (14) for connecting the liquid outlet channel (20) and the liquid spraying pipe (15). The liquid spraying pipe (15) is uniformly and spacedly arranged on the rotating shaft (14) and the liquid sprayed out of the liquid spraying pipe (15) drives the rotating shaft (14) to rotate.

3. The welding device for the automobile sound absorbing cotton according to claim 1, characterized in that: The cooling cavity (2) is provided with an auxiliary cooling structure for driving the inner wall of the cooling cavity (2) and the cooling pipe (3) to contact and conduct heat when the temperature of the end of the welding head (1) away from the welding surface reaches a second preset temperature, and the second preset temperature is less than the first preset temperature.

4. The welding device for the automobile sound absorbing cotton according to claim 3, characterized in that: The auxiliary cooling structure comprises a memory metal rod (17) fixedly connected to the inner wall of the cooling cavity (2) at one end and suspended at the other end in the cooling cavity (2), when the temperature is less than the second preset temperature, the suspended end of the memory metal rod (17) is separated from the cooling pipe (3), and when the temperature is equal to or greater than the second preset temperature, the suspended end of the memory metal rod (17) is attached to the cooling pipe (3).

5. The welding device for the automobile sound absorbing cotton according to claim 4, characterized in that: The memory metal rod (17) is provided with a plurality of intervals along the axial direction of the welding head (1) and around the axial direction of the welding head (1).

6. The welding device for automobile sound absorbing cotton according to claim 4, characterized in that: The cooling pipe (3) is made of a metal material with good heat conduction performance.

Images