A connector bracket assembly welding apparatus

Abstract

This invention relates to the field of laser welding technology, and more particularly to a connector bracket assembly welding device. The invention includes a welder used on an assembly machine, and a limiting frame mounted on the assembly machine for positioning the connector and bracket. A housing is fixedly mounted on the welder. The device also includes a heat-conducting assembly disposed within the housing, comprising two heat-conducting rods slidably disposed within the housing, with heat-conducting plates fixedly mounted at the ends of the heat-conducting rods for movably contacting the connector and bracket. Multiple heat-absorbing chambers are formed within the housing to absorb heat from the surface of the heat-conducting plates. The more heat absorbed in the heat-absorbing chambers, the larger the contact area between the heat-conducting plates and the connector and bracket. By increasing the tightness of the fit and the contact area, the heat absorption rate can be effectively accelerated, preventing deformation of internal connector components such as terminals due to heat during welding, thus further ensuring the quality of the connector during the welding process.

Description

Technical Field

[0001] This invention relates to the field of laser welding technology, and more particularly to a connector bracket assembly welding device. Background Technology

[0002] During the laser welding process between connectors and brackets, the metal workpiece generates a large amount of heat at the moment of welding. Since connectors typically have heat-sensitive components such as precision terminals and insulating plastics pre-assembled inside, if the welding heat is excessively conducted into the connector, it can easily lead to terminal misalignment, deformation of the plastic base, or even melting, directly affecting the electrical performance and mechanical strength of the connector and causing a decrease in product yield.

[0003] To address these issues, existing technologies primarily employ water-cooled fixtures or air-cooled devices to forcibly cool the welding area, using an external cold source to remove excess heat and protect internal components. However, this type of active cooling requires an additional cooling medium circulation system, which not only increases equipment costs and energy consumption but also results in relatively fixed cooling capacity. It is difficult to dynamically adjust this capacity based on the actual heat generated during welding, often leading to insufficient cooling causing terminal damage or excessive cooling affecting welding quality. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a connector bracket assembly and welding device.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: The assembly machine includes a welder for use on an assembly machine, and a limiting bracket installed on the assembly machine for limiting connectors and brackets. The welder has a housing fixedly mounted on it. It also includes: A heat-conducting component is disposed inside the housing for heat conduction on the surfaces of the connector and bracket during welding. The heat-conducting component includes two heat-conducting rods slidably disposed inside the housing, and a heat-conducting plate is fixedly disposed at the end of the heat-conducting rods for movably contacting the connector and bracket. The housing has multiple heat-absorbing cavities for absorbing heat from the surface of the heat-conducting plate, and the more heat absorbed in the heat-absorbing cavities, the larger the contact area between the heat-conducting plate and the connector and bracket.

[0006] Preferably, the heat-absorbing cavity is filled with a phase-changing material, which is paraffin wax.

[0007] Preferably, the heat-conducting assembly further includes a first spring sleeved on the heat-conducting rod, and a push plate is fixedly provided at the end of the heat-conducting rod. The push plate is used to seal the bottom of the heat absorption chamber. When the phase-changing material expands, the push plate pushes the heat-conducting sheet to move through the heat-conducting rod.

[0008] Preferably, the housing is provided with an auxiliary heating component for heat absorption within the heat absorption chamber.

[0009] Preferably, the auxiliary heating assembly includes an auxiliary heating cavity formed within the housing, the auxiliary heating cavity being filled with auxiliary heating oil, and a heating wire spirally arranged on the outer side of the auxiliary heating cavity.

[0010] Preferably, the housing is provided with a control component for temperature control in the auxiliary heating chamber. The control component includes a resistor disposed in the housing and a slider disposed on the lower side of the push plate and in movable contact with the resistor.

[0011] Preferably, the housing is further provided with a vortex tube for preheating and cooling of terminal assembly welding, and the vortex tube is provided with an air inlet pipe that communicates with an external air source, and the air inlet pipe is spirally wound around the outside of the auxiliary heating cavity. The vortex tube is provided with a cooling air inlet and a hot air inlet.

[0012] Preferably, the housing is further provided with an airflow assembly for terminal cooling and preheating. The airflow assembly includes a preheating nozzle and a cooling nozzle, and the preheating nozzle and the cooling nozzle are respectively connected to the cooling airflow port and the hot airflow port of the vortex tube.

[0013] Preferably, the housing is further provided with an adjustment plate for adjusting the size of the air intake pipe, and an air intake port is provided inside the housing, which is connected to the air intake pipe. The adjustment plate is slidably disposed between the air intake pipe and the air intake port. A guide rod is fixedly disposed on the adjustment plate and is fixedly disposed on the heat-conducting plate.

[0014] Compared with the prior art, the beneficial effects of the present invention are: The contact area between the heat-conducting plate and the workpiece automatically increases with the increase of welding temperature through the phase change expansion of paraffin wax. This achieves an adaptive adjustment effect where the heat conduction and absorption capacity increases with the welding temperature, effectively blocking the conduction of welding heat to the internal terminals of the connector and ensuring the safety of precision components. Simultaneously, after welding, the solidification and contraction of the paraffin wax causes the heat-conducting plate to automatically return to its original position, facilitating quick clamping of the next workpiece and improving production efficiency. Furthermore, the paraffin wax melting process synchronously drives the slider to slide on the resistive element, automatically adjusting the heating power of the auxiliary heating chamber heating wire to achieve the desired auxiliary heating power as the temperature of the heat absorption chamber increases. The reverse compensation effect of increasing auxiliary heating power when the temperature of the heat absorption chamber decreases keeps the temperature of the auxiliary heating chamber constant, ensuring continuous preheating of the gas in the inlet pipe. This achieves effective utilization of welding residual heat and automatic optimization of auxiliary heating energy consumption. Furthermore, the vortex tube separates the preheated gas into two streams of hot and cold air. The hot air stream is used for preheating before welding to reduce thermal shock, while the cold air stream is used for rapid cooling after welding to block heat conduction. Combined with the mechanical clamping force of the heat-conducting plate, this achieves the dual effect of suppressing thermal stress throughout the welding process and providing thermal protection for the connector terminals, significantly improving welding quality and product reliability. Attached Figure Description

[0015] Figure 1This is a schematic diagram of the front structure proposed in this invention; Figure 2 This is a schematic diagram of a partial right-side structure proposed in this invention; Figure 3 This is a schematic diagram of a partial left-side structure proposed in this invention; Figure 4 This is a schematic diagram of a partial front structure proposed in this invention; Figure 5 This is a schematic diagram of the interior of a partial upper structure proposed in this invention; Figure 6 This is a schematic diagram of the partial lower internal structure proposed in this invention. Figure 1 ; Figure 7 This is a schematic diagram of the partial lower internal structure proposed in this invention. Figure 2 ; Figure 8 This is a schematic diagram of the workflow proposed in this invention.

[0016] In the diagram: 1. Assembly machine; 2. Welding machine; 3. Limiting frame; 4. Housing; 5. Heat conduction component; 51. Heat conduction rod; 52. Heat conduction plate; 53. First spring; 54. Push plate; 6. Heat absorption chamber; 7. Auxiliary heating component; 71. Auxiliary heating chamber; 72. Heating wire; 8. Control component; 81. Resistor; 82. Sliding plate; 9. Vortex tube; 91. Air inlet pipe; 92. Air inlet; 93. Guide rod; 94. Adjusting plate; 10. Airflow component; 101. Preheating nozzle; 102. Cooling nozzle. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0018] The terms used in this invention, such as "upper," "lower," "left," "right," "middle," and "one," are merely for clarity of description and are not intended to limit the scope of the invention. Any changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0019] Reference Figures 1-8 A connector bracket assembly and welding device includes a welder 2 applied on an assembly machine 1, and a limiting frame 3 disposed on the assembly machine 1 for limiting the connector and bracket. A housing 4 is fixedly disposed on the welder 2; it also includes: A heat-conducting assembly 5 is disposed within the housing 4 for heat conduction between the connector and the bracket surface during welding by the welder 2. The heat-conducting assembly 5 includes two heat-conducting rods 51 slidably disposed within the housing 4, with heat-conducting plates 52 fixedly disposed at the ends of the heat-conducting rods 51 for movably contacting the connector and the bracket. Multiple heat-absorbing chambers 6 are provided within the housing 4 for absorbing heat from the surface of the heat-conducting plates 52; the more heat absorbed in the heat-absorbing chambers 6, the larger the contact area between the heat-conducting plates 52 and the connector and the bracket. (Reference) Figure 1 and Figure 8 The connector and bracket are placed within the limiting frame 3 on the assembly machine 1 (the limiting frame 3 is an existing clamping technology and will not be described in detail). When the welder 2 is welding, the two heat-conducting plates 52 are located on the upper and lower sides of the welder 2, respectively, and at this time, the heat-conducting plates 52 are in contact with the welding points of the bracket and the connector. To improve thermal conductivity, the heat-conducting plates 52 are made of copper plate. During the welding process, the connector and bracket are both metal and will absorb a large amount of heat generated during welding. When the heat-conducting plates 52 are in contact with the bracket and the connection, the heat-conducting plates 52 can effectively absorb the heat generated during the connection. The heat from the surface of the heat exchanger and the bracket is conducted to the heat absorption chamber 6 through the heat-conducting rod 51, where the heat is absorbed, preventing the surface temperature of the heat-conducting plate 52 from becoming too high and losing its heat absorption capacity. When the heat absorption chamber 6 absorbs heat and expands, the expansion force pushes the heat-conducting rod 51 to move, making the heat-conducting plate 52 fit more tightly with the bracket and the surface of the connector. By increasing the tightness of the fit and the contact area, the heat absorption speed can be effectively accelerated, preventing the terminals and other components inside the connector from deforming due to heat during welding, and further ensuring the quality of the connector during the welding process.

[0020] Preferred, Reference Figure 5 The heat absorption cavity 6 is filled with a phase change material, which is paraffin wax, initially in a solid state. When the heat-conducting plate 52 absorbs heat and is transferred to the heat absorption cavity 6 through the heat-conducting rod 51, the paraffin wax absorbs heat and melts. The expansion force generated by melting pushes the heat-conducting rod 51 to move, increasing the contact area between the heat-conducting plate 52 and the bracket and connector, thereby improving the heat absorption efficiency and preventing the internal temperature of the connector from becoming too high during welding. The phase change temperature of the paraffin wax can be adjusted according to the welding process requirements so that it enters the melting and expansion state just when the welding heat is transferred to the heat absorption cavity 6, achieving synchronous response of heat and displacement.

[0021] Preferred, Reference Figure 5The heat-conducting assembly 5 also includes a first spring 53 sleeved on the heat-conducting rod 51; a push plate 54 is fixedly provided at the end of the heat-conducting rod 51, and the push plate 54 is used to seal the end of the heat-absorbing cavity 6; when the phase change material expands, the push plate 54 pushes the heat-conducting sheet 52 to move through the heat-conducting rod 51; when the paraffin melts, the push plate 54 pushes the heat-conducting rod 51 to increase the contact area between the heat-conducting sheet 52 and the bracket, and at the same time, the first spring 53 is stretched when the heat-conducting rod 51 moves; when the temperature in the heat-absorbing cavity 6 drops and the paraffin gradually solidifies and shrinks, the elastic restoring force of the first spring 53 pulls the heat-conducting rod 51 and the heat-conducting sheet 52 back to the initial position, automatically reducing the contact area with the welding point, which facilitates the quick clamping and welding of the next connector.

[0022] Preferred, Reference Figure 5 The housing 4 is also equipped with an auxiliary heating assembly 7. The auxiliary heating assembly 7 includes an auxiliary heating cavity 71 opened in the housing 4. The auxiliary heating cavity 71 is filled with auxiliary heating oil, and a heating wire 72 is spirally arranged on the outer side of the auxiliary heating cavity 71. The auxiliary heating cavity 71 can effectively absorb the heat in the heat absorption cavity 6 to prevent the heat in the heat absorption cavity 6 from being too high. At the same time, the auxiliary heating cavity 71 can also be heated by the heating wire 72. That is, when the temperature in the heat absorption cavity 6 is insufficient, the heating wire 72 can increase the heat in the auxiliary heating cavity 71. When the temperature in the heat absorption cavity 6 is too high, the auxiliary heating cavity 71 can absorb the heat in the heat absorption cavity 6 to keep the temperature in the heat absorption cavity 6 constant, while ensuring that the airflow entering the vortex tube 9 is a hot airflow.

[0023] Preferred, Reference Figure 5 The housing 4 is equipped with a control component 8 for controlling the temperature inside the auxiliary heating chamber 71. The control component 8 includes a resistor 81 disposed inside the housing 4 and a slider 82 disposed below the push plate 54 and in movable contact with the resistor 81. In the initial state, the paraffin is solid, and the resistance between the resistor 81 and the slider 82 is at its minimum, while the heating power of the heating wire 72 is at its maximum. As the temperature inside the auxiliary heating chamber 71 increases and the heat absorbed by the heat-conducting plate 52 increases, the paraffin gradually melts. At this time, the melting paraffin pushes the push plate 54 down, and the slider 82 moves in contact with the resistor 81. The movement of the body 81 increases the resistance of the heating wire 72, thereby changing the heating power of the heating wire 72. When the heat of the heat-conducting plate 52 decreases, the power of the heating wire 72 increases again, which can effectively ensure the melting of paraffin and the temperature inside the auxiliary heating cavity 71, while ensuring the heating temperature of the air inlet pipe 91. This allows the hot airflow in the air inlet pipe 91 to enter the vortex tube 9, causing it to split into hot and cold airflows, which cool and preheat the front and rear sections of the connector bracket. That is, the position after welding is cooled, and the position before welding is preheated to ensure the welding effect.

[0024] Preferred, Reference Figure 5 and Figure 7The housing 4 also includes a vortex tube 9 for preheating and cooling of terminal assembly welding. The vortex tube 9 has an inlet pipe 91 that communicates with an external air source, and the inlet pipe 91 is spirally wound around the outside of the auxiliary heating chamber 71. The vortex tube 9 has cooling air inlets and hot air inlets. External airflow enters the vortex tube 9 through the inlet pipe 91, which is spirally wound around the outside of the auxiliary heating chamber 71. At this time, the auxiliary heating chamber 71 can effectively heat the inlet pipe 91, ensuring that the gas entering the vortex tube 9 is hot air, and simultaneously effectively preheating the welding process. The generated heat is utilized; the vortex tube 9 separates the incoming airflow into hot and cold, so that the airflow acts on the front and rear sides of the welding frame respectively, which can effectively preheat the bracket and connector to be welded, so that the surface temperature of the workpiece rises to close to the welding temperature in advance, thereby reducing the thermal shock at the moment of welding and avoiding thermal stress warping of the bracket and welding device 2 due to low temperature and sudden high temperature; at the same time, the mechanical clamping force generated by the heat-conducting plate 52 driven by the expansion of paraffin can also effectively suppress thermal deformation warping during the welding process, forming a thermo-mechanical synergistic anti-warping effect.

[0025] Preferred, Reference Figure 4 The housing 4 is also equipped with an airflow assembly 10 for terminal cooling and preheating; the airflow assembly 10 includes a preheating nozzle 101 and a cooling nozzle 102, and the preheating nozzle 101 and the cooling nozzle 102 are respectively connected to the cooling airflow port and the hot airflow port of the vortex tube 9, which can effectively discharge the separated airflow in the vortex tube 9 and make it act on the assembled bracket, ensuring that the bracket is preheated and cooled before and after welding, respectively, further improving the welding quality of the equipment; the vortex tube 9 uses the gas vortex effect to separate it into cold airflow and hot airflow, wherein the hot airflow The airflow enters the preheating nozzle 101 through a hose and merges with the hot airflow directly supplied by the air storage chamber to enhance the preheating effect. The cold airflow enters the cooling nozzle 102. Since the cooling nozzle 102 is located on the rear side of the welding machine 2 in the direction of movement, i.e. at the welding completion position, the cold airflow can quickly and locally cool the high-temperature area that has just been welded. On the one hand, it accelerates the solidification of the weld, and on the other hand, it blocks the continuous conduction of heat to the internal terminals of the connector, further ensuring the welding quality of the connector and the bracket, and preventing the precision terminals inside the connector from oxidizing or degrading due to prolonged heating.

[0026] Preferred, Reference Figure 5The housing 4 is also equipped with an adjusting plate 94 for adjusting the size of the air inlet pipe 91; an air inlet 92 is provided inside the housing 4, and the air inlet 92 is connected to the air inlet pipe 91. The adjusting plate 94 is slidably disposed between the air inlet pipe 91 and the air inlet 92; a guide rod 93 is fixedly disposed on the adjusting plate 94, and the guide rod 93 is fixedly disposed on the heat-conducting plate 52; each time the form of paraffin changes, the position of the push plate 54 also changes, and at the same time the guide rod 93 pushes the push plate 54 to change position, thereby changing the air intake between the air inlet pipe 91 and the air inlet 92 according to the position of the push plate 54, so as to adapt to different airflow effects and avoid excessive or insufficient airflow, thereby affecting the welding quality.

[0027] Working principle The connector and bracket are fixed on the limiting frame 3. The welder 2 descends to make the heat-conducting plate 52 fit against the upper and lower sides of the welding point. The high temperature heat generated by welding is transferred to the paraffin in the heat absorption chamber 6 through the copper heat-conducting plate 52 and the heat-conducting rod 51. After absorbing the heat, the paraffin melts from solid to liquid. Its volume expansion pushes the push plate 54 and the heat-conducting rod 51 to move towards the welding point against the elastic force of the first spring 53. This increases the contact area between the heat-conducting plate 52 and the workpiece, making the fit tighter and accelerating the heat absorption speed. This protects the internal terminals of the connector from heat damage. At the same time, the melting of the paraffin pushes the push plate 54 down. The push plate 54 drives the slider 82 to slide on the resistor 81, which increases the resistance of the heating wire 72 and reduces the heating power accordingly. This achieves automatic reduction of the heating power of the auxiliary heating chamber 71 when the temperature of the heat absorption chamber 6 rises. External airflow enters the vortex tube 9 through the intake pipe 91. The intake pipe 91 is spirally wrapped around the outside of the auxiliary heating chamber 71. The auxiliary heating oil in the auxiliary heating chamber 71 preheats the gas in the intake pipe 91. The auxiliary heating chamber 71 maintains its temperature by absorbing the residual heat of the heat absorption chamber 6. When the temperature of the heat absorption chamber 6 is insufficient, the heating wire 72 supplements the heat to keep the auxiliary heating chamber 71 at a constant temperature. The preheated gas enters the vortex tube 9 and is separated into cold airflow and hot airflow through the vortex effect. The hot airflow is sent to the preheating nozzle 101 to preheat the connector and bracket positions to be welded on the front side of the welding machine 2. The cold airflow is sent to the cooling nozzle 102 to rapidly cool the high-temperature area that has been welded on the back side. The mechanical clamping force generated by the heat-conducting plate 52 under the expansion of paraffin works synergistically with the preheating airflow to suppress thermal stress warping during the welding process. The adjusting plate 94 synchronously adjusts the air intake between the air intake pipe 91 and the air intake port 92 according to the position of the push plate 54: when the paraffin melts and pushes the push plate 54 downward, the guide rod 93 drives the adjusting plate 94 to increase the opening of the air intake port 92 and increase the air intake to meet the higher heat dissipation requirements; when the paraffin solidifies and shrinks, the push plate 54 moves upward and drives the adjusting plate 94 to decrease the opening of the air intake port 92 and decrease the air intake, so as to realize the adaptive adjustment of the air intake according to the welding heat load. The contact area between the heat-conducting plate 52 and the workpiece automatically increases with the increase of welding temperature due to the phase change expansion of paraffin wax. This achieves an adaptive adjustment effect where the higher the welding temperature, the stronger the heat conduction and absorption capacity. It effectively blocks the conduction of welding heat to the internal terminals of the connector, ensuring the safety of precision components. Simultaneously, after welding, the solidification and contraction of the paraffin wax causes the heat-conducting plate 52 to automatically reset, facilitating quick clamping of the next workpiece and improving production efficiency. Furthermore, the paraffin wax melting process synchronously drives the slider 82 to slide on the resistor 81, automatically adjusting the heating power of the heating wire 72 in the auxiliary heating cavity 71 to achieve the desired heating power when the temperature of the heat absorption cavity 6 increases. The reverse compensation effect of increased auxiliary heating power when the power is reduced and the temperature of the heat absorption chamber 6 decreases keeps the temperature of the auxiliary heating chamber 71 constant, ensuring continuous preheating of the gas in the air inlet pipe 91. This achieves effective utilization of welding residual heat and automatic optimization of auxiliary heating energy consumption. Furthermore, the vortex tube 9 separates the preheated gas into two streams of hot and cold air. The hot air stream is used for preheating before welding to reduce thermal shock, while the cold air stream is used for rapid cooling after welding to block heat conduction. Combined with the mechanical clamping force of the heat-conducting plate 52, this achieves the dual effect of suppressing thermal stress throughout the welding process and providing thermal protection for the connector terminals, significantly improving welding quality and product reliability.

[0028] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A connector bracket assembly welding device, comprising a welder (2) applied on an assembly machine (1), and a limiting frame (3) disposed on the assembly machine (1) for limiting the connector and bracket, wherein a housing (4) is fixedly disposed on the welder (2): characterized in that, Also includes: A heat-conducting component (5) is installed inside the housing (4) for heat conduction on the surface of the connector and bracket during welding by the welder (2). The heat-conducting component (5) includes two heat-conducting rods (51) that are slidably installed inside the housing (4), and a heat-conducting plate (52) that is in active contact with the connector and bracket is fixedly installed at the end of the heat-conducting rod (51). Multiple heat-absorbing cavities (6) are opened inside the housing (4) for heat absorption on the surface of the heat-conducting plate (52). The more heat absorbed in the heat-absorbing cavity (6), the larger the contact surface between the heat-conducting plate (52) and the connector and bracket.

2. The connector bracket assembly and welding equipment according to claim 1, characterized in that, The heat absorption cavity (6) is filled with a phase-changing material, which is paraffin wax.

3. The connector bracket assembly and welding equipment according to claim 2, characterized in that, The heat-conducting component (5) also includes a first spring (53) sleeved on the heat-conducting rod (51). A push plate (54) is fixedly provided at the end of the heat-conducting rod (51), and the push plate (54) is used to seal the bottom of the heat absorption chamber (6). When the phase-changing material expands, the push plate (54) pushes the heat-conducting sheet (52) to move through the heat-conducting rod (51).

4. The connector bracket assembly and welding equipment according to claim 3, characterized in that, An auxiliary heating component (7) for heat absorption in the heat absorption chamber (6) is provided inside the housing (4).

5. The connector bracket assembly and welding equipment according to claim 4, characterized in that, The auxiliary heating assembly (7) includes an auxiliary heating cavity (71) opened in the housing (4), the auxiliary heating cavity (71) is filled with auxiliary heating oil, and a heating wire (72) is spirally arranged on the outside of the auxiliary heating cavity (71).

6. The connector bracket assembly and welding equipment according to claim 5, characterized in that, The housing (4) is provided with a control component (8) for temperature control in the auxiliary heating chamber (71). The control component (8) includes a resistor (81) disposed in the housing (4) and a slider (82) disposed on the lower side of the push plate (54) and in active contact with the resistor (81).

7. The connector bracket assembly and welding equipment according to claim 6, characterized in that, The housing (4) is also provided with a vortex tube (9) for preheating and cooling of terminal assembly welding, and an air inlet pipe (91) that communicates with an external air source is provided on the vortex tube (9), and the air inlet pipe (91) is spirally wound around the outside of the auxiliary heating cavity (71). The vortex tube (9) is provided with a cooling air outlet and a hot air outlet.

8. The connector bracket assembly and welding equipment according to claim 7, characterized in that, The housing (4) is also provided with an airflow assembly (10) for terminal cooling and preheating. The airflow assembly (10) includes a preheating nozzle (101) and a cooling nozzle (102), and the preheating nozzle (101) and the cooling nozzle (102) are respectively connected to the cooling airflow port and the hot airflow port of the vortex tube (9).

9. The connector bracket assembly and welding equipment according to claim 8, characterized in that, The (4) is also provided with an adjustment plate (94) for adjusting the size of the air intake pipe (91). An air inlet (92) is provided in the housing (4), and the air inlet (92) is connected to the air intake pipe (91). The adjustment plate (94) is slidably disposed between the air intake pipe (91) and the air inlet (92). A guide rod (93) is fixedly disposed on the adjustment plate (94), and the guide rod (93) is fixedly disposed on the heat-conducting plate (52).

Images