A core of a muffler for an automobile, which is composed of a support rod and a partition plate

Abstract

The utility model discloses a kind of automobile muffler core body with quick welding function by support rod and partition, belong to automobile muffler core body welding technical field.Aiming at the problem that the partition and support rod need to rely on welding tool positioning when existing automobile muffler core body assembly welding, leading to low efficiency, tool wear / looseness affects positioning accuracy, unstable welding quality, the application is equipped with hole flanging in partition assembly welding position, supporting rod is formed by secondary stamping process;When assembling, first insert the air pipe and tone pipe into the corresponding partition hole, then install the support rod, then put the core into the welding tool and install the support plate.The core of the application does not need to rely on welding tool positioning, the assembly time is shortened from 72s to 57s, which effectively improves the efficiency;After welding, reduce welding through, partial welding and other defects, improve the strength of weld to avoid bumping and welding, and consider the core assembly efficiency and welding quality stability.

Description

Technical Field

[0001] This application relates to the field of automotive muffler core welding technology, specifically to an automotive muffler core with rapid welding function composed of a support rod and a partition. Background Technology

[0002] The automotive muffler is the core component of the automotive exhaust system. Its core functions are to control exhaust noise, optimize the exhaust flow, and balance environmental protection and engine performance. Its core is usually made up of 8 parts through a process of "pre-assembly followed by welding" to ensure the strength and reliability of the connection between the components.

[0003] In the existing core assembly process, the partition and support rod can only be positioned and assembled by welding fixtures. This results in low assembly efficiency and the fixtures are prone to wear and loosening, which directly affects the positioning accuracy and ultimately makes the welding quality unstable and unreliable.

[0004] Therefore, a technology is needed for the rapid assembly and welding of muffler core components, which can both ensure welding quality and increase production output. Summary of the Invention

[0005] To address the aforementioned technical problems, this application solves the technical issues in the existing automotive muffler core assembly and welding process, where the partition and support rod rely on welding fixtures for positioning, resulting in low efficiency, positioning accuracy being easily affected by fixture wear / loosening, and unstable and unreliable welding quality.

[0006] To achieve the above objectives, the technical solution adopted in this application is as follows: a car muffler core with rapid welding function composed of support rods and partitions, including a first partition, a second partition, a third partition, an exhaust pipe and a tuning pipe for the car muffler core, wherein the first partition, the second partition and the third partition are provided with stamped first flip holes, and a long support rod is provided on the first flip holes of the three partitions for supporting the lower ends of the three partitions.

[0007] The first partition has a second flip hole with a short support rod. The short support rod is connected to the first and second partitions. A support plate is provided between the second and third partitions for connecting the air pipe. The short support rod and the support plate are used to support the upper ends of the three partitions.

[0008] The air outlet pipe is installed in the through holes of the three partitions, and the tuning pipe is installed on the first partition and the second partition.

[0009] Preferably, the fit clearance between the long support rod and the short support rod and the flip hole is 0.2-0.8 mm.

[0010] Preferably, the flip hole is formed by stamping an annular boss on the surface of the partition plate, with a through circular channel formed in the center of the boss. The diameter of the channel is 10-11 mm, and the height of the annular boss is 2.5-3.5 mm.

[0011] Preferably, the long support rod is a cylindrical metal rod with a diameter of 9.7-10.3 mm, and the length of the long support rod matches the spacing between two adjacent partitions.

[0012] Preferably, the perforation is achieved through a secondary stamping process.

[0013] Preferably, the welding penetration depth of each component of the core is ≥0.2mm, the weld bead height is ≥0.7mm, the weld bead width is ≥1mm, and the overlap height is 1mm.

[0014] The technical solution provided in this application has the following advantages compared with the prior art:

[0015] 1. This application optimizes the partition structure so that the partition and support rod can be positioned directly by the cooperation of the flip-hole and the support rod, eliminating the need to rely on welding fixtures for positioning, simplifying the assembly process and reducing dependence on tooling.

[0016] 2. The optimized assembly process of this application shortens the core assembly time. Specific data shows that the welding assembly time is reduced from 72s in the original process to 57s, and the assembly time of a single core is reduced by 15s, effectively improving production output.

[0017] 3. The fit clearance (0.2~0.8mm) between the hole and the support rod in this application meets the welding process requirements, which reduces common quality defects such as burn-through, off-center welding, and incomplete weld bead after welding, and makes the weld bead formation more stable.

[0018] 4. The weld strength of this application is more stable after welding, which can effectively eliminate the problem of weld detachment caused by bumps and vibrations during vehicle operation; at the same time, the deformation of the partition is significantly reduced from 4-5mm before optimization to less than 3mm, which improves the overall structural accuracy of the core. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the welding fixture used in this application;

[0020] Figure 2 This is a schematic diagram of the core structure of this application;

[0021] Figure 3 This is a cross-sectional view of the flap hole in the partition of this application;

[0022] Figure 4 This is a schematic diagram showing the connection between the support rod and the partition plate in this application;

[0023] Figure 5This is a schematic diagram of the installation of the long support rod and the short support rod in this application.

[0024] In the diagram: 101-Support plate; 102-Short support rod; 103-Long support rod; 201-Third partition; 202-Second partition; 203-First partition; 204-Tuning pipe; 205-Air outlet pipe. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0027] like Figures 1 to 5 As shown, a car muffler core with rapid welding function is composed of support rods and partitions. It is characterized by including a first partition 203, a second partition 202, a third partition 201, an exhaust pipe 205, and a tuning pipe 204 for the car muffler core. The first partition 203, the second partition 202, and the third partition 201 are all provided with stamped first flip holes. A long support rod 103 is provided on the first flip holes of the three partitions to support the lower ends of the three partitions.

[0028] The partitions are made of 1.5-2.0mm thick cold-rolled steel plates. This material has good stamping and welding properties, which can avoid secondary stamping cracks and meet the strength requirements of the core structure. The flatness tolerance of the three partitions is controlled within ≤0.3mm to prevent the warping of the plate surface from causing the coaxiality deviation of the first flip hole and to ensure that the spacing between the partitions is uniform after the long support rod is inserted.

[0029] The long support rod is a cylindrical rod made of low carbon steel (such as Q235), with a diameter strictly controlled at φ10±0.3mm. The length matches the design spacing of the adjacent partitions with a tolerance of ±0.5mm. Through the direct cooperation between the flip-hole and the support rod, there is no need to rely on welding fixtures for positioning. The initial positioning time is reduced by 1 / 3 compared with the original fixture positioning method, realizing "quick pre-fixing without fixtures".

[0030] The first partition 203 is provided with a second flip hole, and a short support rod 102 is provided on the second flip hole. The short support rod 102 is connected to the first partition 203 and the second partition 202. A support plate 101 is provided between the second partition 202 and the third partition 201 for connecting the air pipe. The short support rod 102 and the support plate 101 are used to support the upper ends of the three partitions.

[0031] The support plate is made of 1.5-2.0mm thick cold-rolled steel plate of the same material as the partition plate. The plate has a round hole that is 0.1-0.2mm larger than the outer diameter of the air pipe. It is fixed between the second and third partition plates by positioning blocks and positioning pins.

[0032] The short support rod also has a diameter of φ10±0.3mm, forming a "symmetrical support" structure with the long support rod, which avoids the three partitions from tilting up and down during assembly and welding, thus improving the overall support stability of the core by 40%.

[0033] The air outlet pipe 205 is installed on the through holes of the three partitions, and the tuning pipe 204 is installed on the first partition 203 and the second partition 202.

[0034] The diameter of the through holes for the air outlet pipes on the three partitions is 0.1-0.2mm larger than the outer diameter of the air outlet pipes. The clearance fit design facilitates quick insertion of the air pipes and avoids deformation of the partition surface caused by interference fit. The coaxiality tolerance of the through holes is ≤0.15mm, ensuring that the axis of the air outlet pipe is straight after installation, reducing exhaust airflow resistance, and matching the core function of the muffler to "control exhaust noise".

[0035] The tuning tube is designed with a 30°-45° chamfer at the end, with a length of 0.5-1mm, to guide it smoothly into the through holes of the first and second partitions and avoid scratching the inner wall of the through holes; and the tuning tube is made of stainless steel (suitable for the high-temperature exhaust environment of the muffler at 300-600℃), which has better corrosion resistance than carbon steel and extends the service life of the core.

[0036] During assembly, first insert the air outlet pipe and tuning pipe into the corresponding holes of the partition plate, then insert the support rod into the flip hole, then place the core body as a whole into the welding fixture positioning plate and push in the pipe positioning pin, finally install the support plate and insert the positioning pin, and start the cylinder to clamp and complete the clamping.

[0037] The fitting clearance between the long support rod 103 and the short support rod 102 and the flip hole is 0.2-0.8mm.

[0038] A lower gap of 0.2mm can avoid interference fit between the support rod and the flip hole: prevent the situation of "needing to knock to assemble", ensure that the support rod can be quickly inserted by hand, and shorten the assembly time of a single core; an upper gap of 0.8mm can meet the welding process requirements: avoid the loss of molten pool metal during welding due to excessive gap, and prevent defects such as weld burn-through and incomplete weld.

[0039] This gap range has been verified in actual production, which can reduce the core assembly time from the original 72s to 57s, saving 15s. At the same time, the welding qualification rate has been increased from 85% of the original process to more than 98%, taking into account both the requirements of "rapid assembly" and "welding quality".

[0040] The flip hole is formed by stamping an annular boss on the surface of the partition plate. A through circular channel is formed in the center of the boss. The diameter of the channel is 10-11mm and the height of the annular boss is 2.5-3.5mm.

[0041] The wall thickness of the annular boss is controlled at 1.0-1.2mm. A radius of 0.5mm is designed at the transition between the boss and the partition plate to eliminate stress concentration during stamping and welding and prevent cracking at the root of the boss. The diameter of the hole is 10-11mm and the height is 2.5-3.5mm to ensure that the support rod has sufficient mating length after insertion and to avoid the support rod shaking after assembly.

[0042] The long support rod 103 is a cylindrical metal rod with a diameter of 9.7-10.3 mm, and the length of the long support rod 103 matches the spacing between two adjacent partitions.

[0043] The matching accuracy between the length and the spacing between adjacent partitions is ±0.5mm, ensuring that the spacing between the partitions after insertion is consistent with the design value (e.g., when the design spacing is 50mm, the actual spacing is 49.5-50.5mm), avoiding partition deformation or loosening of the support due to length deviation, ensuring the overall dimensional accuracy of the core, and adapting to the assembly requirements of the muffler housing.

[0044] The perforation is achieved through a secondary stamping process.

[0045] The first step involves using a 125T punch press to blank the sheet metal and simultaneously punch out pre-punched holes of φ7.7±0.3mm; the second step involves using a 200T punch press to flanging the pre-punched sheet metal to form the flanged holes.

[0046] The welding penetration depth of each component of the core is ≥0.2mm, the weld bead height is ≥0.7mm, the weld bead width is ≥1mm, and the overlap height is 1mm.

[0047] A weld penetration depth of ≥0.2mm ensures full welding between the support rod and the flanged joint surface, avoiding long-term stress-induced peeling caused by surface welding. In practice, by adjusting the welding current to 120-150A and the welding speed to 5-8mm / s, the weld penetration depth can be stabilized at 0.6-0.8mm, meeting the load requirements of vibration acceleration during vehicle operation.

[0048] A weld bead height of ≥0.7mm and a width of ≥1mm can avoid defects such as porosity and slag inclusions. The actual bead height can reach 1.5-1.6mm and the width can reach 4.6-4.7mm, resulting in a full weld bead formation. The overlap surface height of 1mm can increase the welding area of ​​stress concentration points, enabling the weld to achieve a 100% pass rate in vibration fatigue tests, which is far higher than the original process's 80% pass rate.

[0049] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A car muffler core with rapid welding function, comprising a support rod and a partition plate, characterized in that, The device includes a first partition (203), a second partition (202), a third partition (201), an exhaust pipe (205), and a tuning pipe (204) for the core of an automotive muffler. The first partition (203), the second partition (202), and the third partition (201) are all provided with stamped first flip holes. A long support rod (103) is provided on the first flip holes of the three partitions to support the lower ends of the three partitions. The first partition (203) is provided with a second flip hole, and a short support rod (102) is provided on the second flip hole. The short support rod (102) is connected to the first partition (203) and the second partition (202). A support plate (101) is provided between the second partition (202) and the third partition (201) for connecting the air pipe. The short support rod (102) and the support plate (101) are used to support the upper ends of the three partitions. The air outlet pipe (205) is installed on the through holes of the three partitions, and the tuning pipe (204) is installed on the first partition and the second partition.

2. The automotive muffler core with rapid welding function, composed of a support rod and a partition plate, as described in claim 1, is characterized in that... The fitting clearance between the long support rod (103) and the short support rod (102) and the flip hole is 0.2-0.8mm.

3. The automotive muffler core with rapid welding function, comprising a support rod and a partition plate, as described in claim 1, is characterized in that... The flip hole is formed by stamping an annular boss on the surface of the partition plate. A through circular channel is formed in the center of the boss. The diameter of the channel is 10-11mm and the height of the annular boss is 2.5-3.5mm.

4. A car muffler core with rapid welding function, comprising a support rod and a partition plate, as described in claim 1, characterized in that... The long support rod (103) is a cylindrical metal rod with a diameter of 9.7-10.3 mm. The length of the long support rod (103) matches the spacing between two adjacent partitions.

5. A car muffler core with rapid welding function, comprising a support rod and a partition plate, as described in claim 1, characterized in that... The perforation is achieved through a secondary stamping process.

6. A car muffler core with rapid welding function, comprising a support rod and a partition plate, as described in claim 1, characterized in that... The welding penetration depth of each component of the core is ≥0.2mm, the weld bead height is ≥0.7mm, the weld bead width is ≥1mm, and the overlap height is 1mm.

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