Automatic welding method and system for throttle assembly

Abstract

This invention relates to the field of intelligent manufacturing technology for throttle bodies, specifically to an automatic welding method and system for throttle body assembly. The method involves driving the valve shaft to rotate, causing the valve plate to rotate within the throttle body to a target opening position. At this point, the throttle body's intake air volume reaches the target idle speed intake air volume simulating engine idling. When the valve plate rotates to the target opening position, the reference position of the sector teeth is determined. The valve shaft is driven to rotate again, causing the valve plate to rotate completely within the throttle body to the mechanical stop position and lock it. The rotation angle θ of the valve shaft when the valve plate rotates from the target opening position to the mechanical stop position is calculated. When the valve plate is determined to be completely rotated to the mechanical stop position, the sector teeth are rotated according to the rotation angle θ, causing the sector teeth to rotate from the reference position to the actual welding position. The sector teeth and valve shaft are then welded at the actual welding position. By using these two positions to find the rotation angle θ of the valve shaft, the position of the sector teeth is adjusted accordingly, ensuring assembly accuracy and improving the uniformity of throttle body product performance.

Description

Technical Field

[0001] This invention relates to the field of intelligent manufacturing technology for throttle bodies, and in particular to an automatic welding method and system for throttle body assembly. Background Technology

[0002] In the field of automotive engine control, the electronic throttle is a key actuator for controlling the intake air volume and a crucial component for precisely adjusting the intake air volume. Its performance directly affects the engine's idling stability.

[0003] During the welding assembly process of sector teeth and valve shaft, the welding industrial robot pushes the valve plate with a pneumatic push rod to move it to the mechanical stop position and sets this position as the assembly reference. Then, based on this reference position, the sector teeth are adjusted to a preset fixed angle before welding. The setting of this fixed angle is to ensure that the valve plate is at a predetermined opening degree when the assembled throttle valve is initially started, so that the car can maintain idle speed.

[0004] However, due to the unavoidable tolerances in the processing and assembly of mechanical parts, the actual position of the valve plate when it reaches the mechanical stop position is not an absolutely constant point, but a range that fluctuates within a certain range. This directly results in the initial intake volume of the throttle body not being a fixed value at this reference position. Based on this fluctuation, and using a fixed sector welding angle, the actual initial opening angle and corresponding intake volume of the valve plate of each throttle body after welding and assembly will differ. When these throttle bodies are installed on automobiles, this will manifest as inconsistent idle speeds between vehicles, seriously affecting the uniformity, reliability, and overall quality experience of the product. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the problem that the intake volume of the throttle body after assembly is different in the initial position when it is actually installed and used due to the tolerance of the parts in the prior art. Therefore, an automatic welding method and system for throttle body assembly is proposed. The rotation angle θ of the valve shaft is found through two positions, and the position of the sector teeth is adjusted accordingly to ensure the accuracy of assembly and improve the uniformity of throttle body product performance.

[0006] To solve the above-mentioned technical problems, the present invention provides an automatic welding method for throttle body assembly, applied to the welding of the valve shaft and sector teeth of the throttle body, wherein a valve plate is mounted on the valve shaft, and includes the following steps:

[0007] S1. Drive the valve shaft to rotate, causing the valve plate to rotate in the throttle valve to the target opening position. At this time, the intake air volume of the throttle valve reaches the target idle speed intake air volume simulating the engine idle speed state.

[0008] S2. When the valve plate rotates to the target opening position, determine the reference position of the sector teeth;

[0009] S3. Drive the valve shaft to rotate again, causing the valve plate to rotate completely in the throttle body to the mechanical stop position, and lock it in that position;

[0010] S4. Calculate the rotation angle θ of the valve shaft when the valve plate rotates from the target opening position to the mechanical stop position;

[0011] S5. When the valve plate is fully rotated to the mechanical stop position, rotate the sector teeth according to the rotation angle θ, so that the sector teeth rotate from the reference position to the actual welding position, and weld the sector teeth and valve shaft at the actual welding position.

[0012] In one embodiment of the present invention, step S1, using a test air circuit to simulate the engine idling state, determines the target opening position of the valve plate, including the following steps:

[0013] S11. Seal the throttle valve outlet to the test air circuit, and expose the air inlet to the atmosphere.

[0014] S12. Start the test air circuit to simulate the engine idling intake condition;

[0015] S13, drive the valve shaft to rotate and monitor the gas flow parameters flowing through the throttle valve in real time;

[0016] S131. When the gas flow rate parameter reaches and stabilizes at the preset target idle speed intake volume, record the valve plate position at this time as the target opening position.

[0017] In one embodiment of the present invention, step S3, determining that the valve shaft has fully rotated to the mechanical stop position, includes the following steps:

[0018] S31, drive the valve shaft to rotate in the forward direction and monitor the output torque of the servo motor that drives the valve shaft to rotate in real time;

[0019] S32. When the output torque is detected to increase for the first time and reach the preset torque, record the position of the valve shaft at this time as the first contact position.

[0020] S33, reverse drive servo motor rotates by a preset yield angle, while simultaneously introducing N pulse airflows into the throttle valve passage;

[0021] S34. Drive the valve shaft to rotate in the forward direction again until it reaches the first contact position, and continuously monitor the output torque;

[0022] S341. If the output torque jumps synchronously when the first contact position is reached again, it is determined that the valve plate has fully reached the mechanical stop position and the valve shaft position is locked.

[0023] S342. If the output torque does not increase synchronously, repeat steps S31-S34 until a torque increase that meets the requirements is stably detected at the same position during continuous forward drive.

[0024] In one embodiment of the present invention, the synchronous leap is defined as follows: when the valve shaft rotates to the first contact position again, the output torque changes in the same magnitude and trend as the output torque recorded when it rotates to the first contact position the previous time.

[0025] In one embodiment of the present invention, the gas flow parameter is the volumetric flow rate or mass flow rate passing through the throttle valve under standard conditions.

[0026] In one embodiment of the present invention, the target idle intake volume is determined by one of the following methods:

[0027] The optimal intake air volume required to maintain the target idle speed is directly obtained from the electronic control unit calibration database of the target engine.

[0028] Based on the engine's design parameters such as displacement, compression ratio, and valve timing, the theoretical intake volume required to maintain idle speed is calculated through engine operation simulation.

[0029] In engine bench tests, the actual intake volume corresponding to the engine operating at the most stable idle speed with the lowest emissions is found by adjusting the throttle opening.

[0030] An automated welding system for throttle body assembly is also provided, for implementing the aforementioned automated welding method for throttle body assembly, including:

[0031] The welding station is used to adjust the position of the sector teeth and weld them to the valve shaft.

[0032] The gas station is configured to simulate engine idling and provide pulsed airflow;

[0033] Throttle body clamping fixture, used to clamp and fix the throttle body, and sealed and connected to the gas station;

[0034] The control and computing unit is connected to the welding station, the gas station, and the throttle clamping fixture signals, respectively.

[0035] In one embodiment of the present invention, the throttle clamping fixture includes:

[0036] Mounting base;

[0037] A vertical mounting base has a connection hole with a sealing element inside the connection hole;

[0038] The positioning mold is installed on one side of the base surface of the vertical mounting base;

[0039] A set of fixing claw components is installed on a vertical mounting base;

[0040] The drive motor assembly is mounted on the mounting base below the positioning mold and is used to drive the valve shaft to rotate.

[0041] The thermal mass flow meter is used to monitor the gas flow parameters passing through the throttle valve in real time. It is installed with a sealed connection hole and is in sealed connection with the gas station.

[0042] When the throttle body is installed on the positioning mold, the throttle body's air outlet is connected to the connecting hole. When the throttle body is fixed by the fixing claw assembly, the throttle body's air outlet is sealed to the connecting hole.

[0043] In one embodiment of the present invention, the drive motor assembly includes:

[0044] Servo driver;

[0045] The lifting base is used to move the servo drive up and down.

[0046] The connector, installed at the power output end of the servo drive, is used to connect to the throttle valve shaft.

[0047] In one embodiment of the present invention, the connecting hole is streamlined and tapers from one end of the mounting positioning mold to the end of the mounting thermal mass flow meter.

[0048] The technical solution of the present invention has the following advantages over the prior art:

[0049] The automatic welding method and system for throttle body assembly described in this invention compensates for the inconsistency in initial idle air intake caused by component tolerances from the assembly step. It ensures that each throttle body is extremely close to the theoretical optimal intake volume, i.e., the target idle air intake volume, in its initial mechanical position upon startup. By first determining the target opening position required for the target idle air intake volume of the throttle body, and then determining the precise mechanical stop position, the rotation angle θ of the valve shaft is calculated using these two positions. Based on the rotation angle θ, the angle that the final sector teeth need to be adjusted relative to the reference position is determined. This ensures that regardless of changes in component tolerances, each throttle body can find its own standard welding position in this solution. It ensures that when the assembled throttle body is actually installed and used in a vehicle, the valve plate is precisely positioned to provide the target idle air intake volume upon starting the throttle body, thereby guaranteeing the consistency of idle performance of subsequent automotive products and reducing the adjustment burden on the ECU. Attached Figure Description

[0050] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein...

[0051] Figure 1 This is a flowchart illustrating the automatic welding method for throttle body assembly according to the present invention.

[0052] Figure 2 This is a schematic diagram of the process steps of the present invention to determine the target opening position of the valve plate by simulating the engine idling state using a test air circuit;

[0053] Figure 3 This is a schematic diagram illustrating the criteria for determining the target opening position according to the present invention;

[0054] Figure 4 This is a schematic diagram of the process for determining the valve shaft to be fully rotated to the mechanical stop position according to the present invention;

[0055] Figure 5 This is a structural block diagram of the automatic welding system for throttle body assembly of the present invention;

[0056] Figure 6 This is a schematic diagram of the throttle body clamping fixture structure of the present invention;

[0057] Figure 7 This is a schematic diagram of the throttle clamping fixture structure from another perspective of the present invention;

[0058] Figure 8 This is a schematic diagram of the sealing ring of the present invention;

[0059] Figure 9 This is a top sectional view of the throttle body clamping fixture of the present invention;

[0060] Figure 10 This is a schematic diagram showing the positional changes of the valve plate, valve shaft, and sector teeth in this invention.

[0061] Explanation of reference numerals in the accompanying drawings: 1. Mounting base; 2. Vertical mounting base; 21. Connecting hole; 3. Seal; 4. Positioning mold; 5. Fixing claw assembly; 6. Drive motor assembly; 61. Servo driver; 62. Lifting base; 63. Connector; 7. Thermal mass flow meter; 8. Valve plate; 9. Valve shaft; 10. Sector gear. Detailed Implementation

[0062] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0063] Currently, in the automated assembly process of throttle bodies, the fixing process of valve shaft 9 and sector tooth 10 usually adopts the mechanical stop position as the reference, and welding is performed by adding a fixed angle on this reference. However, due to the unavoidable production and assembly tolerances of mechanical parts, although these tolerances are within the range allowed by the process, in actual applications, for example, the valve plate 8 of different throttle bodies actually has a fluctuating range at the mechanical stop position. Adding a fixed angle on the basis of the fluctuation results in a final angle that is also a fluctuating value. This leads to the initial intake volume of each throttle body sector tooth 10 driving the valve plate 8 to open fluctuating after the final welding. After the throttle body is installed on the car, the engine control unit (ECU) needs to make different adjustments to each throttle body to maintain the consistency of the car's idle speed.

[0064] Reference Figure 1 , 10 As shown, the automatic welding method for throttle body assembly of the present invention is applied to the welding of the valve shaft 9 and the sector tooth 10 of the throttle body. A valve plate 8 is mounted on the valve shaft 9, and the method includes the following steps:

[0065] S1. Drive the valve shaft 9 to rotate, causing the valve plate 8 to rotate in the throttle valve to the target opening position. At this time, the intake air volume of the throttle valve reaches the target idle speed intake air volume simulating the engine idle speed state.

[0066] S2. When the valve plate 8 rotates to the target opening position, determine the reference position of the sector tooth 10. It should be noted that in actual applications, the sector tooth 10 is usually connected to the drive component through an intermediate gear. When the drive component is started, the power is transmitted to the sector tooth 10 through the intermediate gear. The sector tooth 10 drives the valve shaft 9 to rotate, thereby placing the valve plate 8 in an opening position. In this solution, the position of the sector tooth 10 is bound to the valve shaft 9 at the target idle air volume position by reverse pushing. During assembly, the position of the sector tooth 10 is used to align with the intermediate gear and the drive component. When the subsequent welding is completed, the drive component is started, and the sector tooth 10 drives the valve shaft 9 to rotate. At this time, the valve plate 8 is exactly at the target opening position.

[0067] S3. Drive the valve shaft 9 to rotate again, causing the valve plate 8 to rotate completely in the throttle valve to the mechanical stop position, and lock it in that position;

[0068] S4. Calculate the rotation angle θ of valve shaft 9 when valve plate 8 rotates from the target opening position to the mechanical stop position;

[0069] S5. When the valve plate 8 is fully rotated to the mechanical stop position, rotate the sector tooth 10 according to the rotation angle θ, so that the sector tooth 10 rotates from the reference position to the actual welding position, and weld the sector tooth 10 and the valve shaft 9 at the actual welding position.

[0070] The core of this solution is to propose a dynamic welding method based on each throttle body itself. Instead of adding a fixed angle, it calculates the welding position that fits each throttle body by calibrating two key positions.

[0071] That is, under standardized airflow conditions simulating engine idling, find the position of valve plate 8 that can provide precise target idling intake air volume;

[0072] Then, the mechanical stop position of the current throttle body is confirmed with high precision, and this position is used as the fixed position of the valve shaft 9 during welding.

[0073] Finally, the rotation angle θ of the valve shaft 9 is calculated when the valve plate 8 rotates from the target opening position to the mechanical stop position. Then, the sector gear 10 is calibrated with the reference position, rotated through a rotation angle θ, and then welded and fixed. In this way, after welding, the influence of part tolerance on the throttle idle air volume is eliminated from the assembly steps. While ensuring the consistency of throttle function, it provides the ECU with an extremely stable idle air volume operating point after actual installation in the car, without the need for significant correction.

[0074] Based on the above scheme, this scheme constructs a test air circuit that can easily simulate the idling operation of an engine. Using this test air circuit to simulate the engine idling state, the target opening position of valve plate 8 is determined, with reference to... Figure 2 , 3 As shown, step S1 includes the following steps:

[0075] S11. Seal the throttle valve outlet to the test air circuit, and expose the air inlet to the atmosphere.

[0076] S12. Start the test air circuit to simulate the engine idling intake condition;

[0077] S13 drives the valve shaft 9 to rotate and monitors the gas flow parameters flowing through the throttle valve in real time;

[0078] S131. When the gas flow rate parameter reaches and stabilizes at the preset target idle speed intake volume, record the position of valve plate 8 at this time as the target opening position.

[0079] The core of this solution lies in using the final function as the calibration, that is, using the target idle air intake volume to be achieved as the calibration. When the valve plate 8 reaches the target opening position, the air intake volume that the test air circuit simulates when the engine is idling and flows through the throttle valve is the target idle air intake volume. This eliminates the influence of the valve plate 8 tolerance on the intake volume. For example, the shape and size of different valve plates 8 are all within the allowable range of the process, but due to the existence of production and assembly tolerances, they will reach the target idle air intake volume at different positions when rotating. However, this solution uses the final function as the calibration, so the intake volume of each throttle valve at the target opening position is the target idle air intake volume.

[0080] In the above, a target idle air volume with the final stable idle speed was obtained as a calibration, and the actual welding position of the sector tooth 10 was obtained. Then, another valve shaft 9 position that can be fixed for welding needs to be obtained. In the prior art, a push rod is usually used to push the valve plate 8 to abut against the mechanical stop position of the throttle valve. However, this method is extremely crude and cannot determine whether the position of the valve plate 8 has just reached the mechanical stop position. Too much or too little pushing force will eventually affect the assembly accuracy. Therefore, the prior art adds thrust monitoring feedback, which greatly improves the assembly accuracy. However, the process of pushing the valve plate 8 to rotate is unidirectional. If there are small debris on the valve plate 8 or the mechanical stop, it will also provide feedback on the force at this time, thus mistakenly believing that the valve plate 8 has completely reached the mechanical stop position. However, there is still a gap of debris between the valve plate 8 and the mechanical stop. If welding is performed at this position, the position of the mechanical stop will change after the debris is cleaned up. As a result, even if the precise welding position of the sector tooth 10 is determined, the valve plate 8 cannot be at the optimal target opening at the start, but is offset from the optimal target opening by a small angle.

[0081] Therefore, in this solution, the goal is to ensure that the valve plate 8 fully reaches the mechanical stop position, such as... Figure 4 As shown, this scheme, as a detailed step for determining that the valve shaft 9 has fully rotated to the mechanical stop position in step S3, includes:

[0082] S31, drive valve shaft 9 to rotate in the forward direction, and monitor the output torque of the servo motor that drives valve shaft 9 to rotate in real time;

[0083] S32. When the output torque is detected to jump for the first time and reach the preset torque, record the position of the valve shaft 9 at this time as the first contact position. The first contact position here means that the valve shaft 9 is in a position when the valve plate 8 and the mechanical stop on the throttle passage may come into contact. Whether the valve plate 8 and the mechanical stop are definitely in contact needs to be verified in subsequent steps.

[0084] S33, reverse drive servo motor rotates by a preset yield angle, while simultaneously introducing N pulse airflows into the throttle valve passage;

[0085] S34. Drive the valve shaft 9 to rotate in the forward direction again until it reaches the first contact position, and continuously monitor the output torque;

[0086] S341. If the output torque increases synchronously when the first contact position is reached again, it is determined that the valve plate 8 has completely reached the mechanical stop position and the valve shaft 9 position is locked.

[0087] S342. If the output torque does not increase synchronously, repeat steps S31-S34 until a torque increase that meets the requirements is stably detected at the same position during continuous forward drive.

[0088] The core of this solution is to find a perfectly precise mechanical stop position and use this position as the fixed position of valve plate 8 and valve shaft 9 during welding. This can avoid deviations caused by inaccurate fixed positions of valve plate 8 and valve shaft 9.

[0089] In one implementation, valve shaft 9 is driven to rotate, and valve plate 8 rotates accordingly. During this process, the output torque is monitored in real time. When there is no contact with the mechanical stop, the output torque is maintained at a low value. At this time, the output torque is mainly used to overcome the static friction, dynamic friction, and resistance torque of rotating parts such as bearings inside the system. When the output torque is detected to have its first jump and reach the preset torque, it proves that valve plate 8 may be in contact with the mechanical stop, but there is still a situation similar to the prior art, that is, there are debris. The position of valve shaft 9 at this time is recorded as the first contact position. Further, the reverse drive servo motor rotates by a preset yield angle to introduce multiple pulse airflows into the throttle valve passage to blow away the tiny debris that may exist on the contact surface. After the blowing is completed, it rotates forward to the first contact position. If the torque is synchronized with the previous arrival when the first contact position is reached again, that is, the torque jumps synchronously, it proves that the mechanical stop position has indeed been reached. If the torque changes when the first contact position is reached again, it proves that there are debris on the contact surface. The above operation is repeated until the output torque jumps synchronously with the previous arrival.

[0090] like Figure 4 As shown, the synchronous leap is: when the valve shaft 9 rotates to the first contact position again, the output torque changes in the same magnitude and trend as the output torque recorded when it rotates to the first contact position the previous time. The core of this scheme is to use two consecutive torque changes as the criterion, that is, to compare the torque recorded at the same position twice in a row, and to ensure that the current position is a stable and definite position by judging whether the curve shape of the torque is highly overlapping or even consistent.

[0091] like Figure 2 , 3As shown, the gas flow parameters are the volumetric flow rate or mass flow rate flowing through the throttle valve under standard conditions. In this scheme, a thermal mass flow meter 7 can be used for measurement, and the reading can be read directly. It can be either volumetric flow rate or mass flow rate. Its principle is quite mature in the existing technology, so it will not be elaborated on here.

[0092] The target idle intake volume is determined by one of the following methods:

[0093] The optimal intake air volume required to maintain the target idle speed is directly obtained from the electronic control unit calibration database of the target engine.

[0094] Based on the engine's design parameters such as displacement, compression ratio, and valve timing, the theoretical intake volume required to maintain idle speed is calculated through engine operation simulation.

[0095] In engine bench tests, the actual intake volume corresponding to the engine operating at the most stable idle speed with the lowest emissions is found by adjusting the throttle opening.

[0096] The core of this solution lies in obtaining the target idle air volume through methods and approaches found in real-world application scenarios. In this solution, all parameter determinations are based on this definite data, with this fixed value serving as the ultimate goal. Automated calibration and compensation welding are then performed to ensure that every product off the production line meets the same performance indicators of the engine.

[0097] Based on the above-mentioned automatic welding method for throttle body assembly, an additional automatic welding method for throttle body assembly is proposed to implement the aforementioned automatic welding method, such as... Figure 5 As shown, it includes: a welding station for adjusting the position of the sector teeth 10 and welding the sector teeth 10 to the valve shaft 9;

[0098] The gas station is configured to simulate engine idling and provide pulsed airflow;

[0099] Throttle body clamping fixture, used to clamp and fix the throttle body, and sealed and connected to the gas station;

[0100] The control and computing unit is connected to the welding station, the gas station, and the throttle clamping fixture signals, respectively.

[0101] In this scheme, a welding system capable of implementing the above-mentioned automatic welding method is constructed. The gas station is configured as a simulated idle speed gas circuit and a pulse generator. The simulated idle speed gas circuit consists of a vacuum pump, a pressure stabilizing tank, connecting pipelines, and a regulating valve, which is used to provide and maintain the test negative pressure and keep the test negative pressure constant and stable.

[0102] The welding station is a comprehensive manufacturing unit that integrates precision welding, online quality inspection and intelligent monitoring functions. During the welding process, it acts as an actuator to precisely adjust the position of the sector teeth 10 and perform welding actions.

[0103] like Figure 6 , 7 As shown in Figure 8, the throttle body clamping fixture includes:

[0104] Mounting base 1;

[0105] A vertical mounting base 2 has a connecting hole 21 on it;

[0106] Positioning mold 4 is installed on one side of the base surface of vertical mounting base 2; it is configured to match the current throttle body model, has multiple positioning pins and support protrusions for positioning and supporting the throttle body housing, and is also configured for quick-release installation so that positioning mold 4 can be quickly replaced when changing product models;

[0107] A set of fixing claw assemblies 5 are installed on the vertical mounting base 2. In use, the two fixing claw assemblies 5 are symmetrically arranged relative to the throttle valve inlet. Specifically, the fixing claw assembly 5 is configured as a linear rotary cylinder with claw clamps at the output end of the cylinder. When the throttle valve is installed on the positioning mold 4, the linear rotary cylinder drives the claw clamps to rotate and retract, pressing and fixing the throttle valve housing onto the positioning mold 4. At this time, the throttle valve outlet passes through the positioning mold 4 and communicates with the connecting hole 21, and is sealed at the interface.

[0108] The drive motor assembly 6 is mounted on the mounting base 1 below the positioning mold 4 and is used to drive the valve shaft 9 to rotate.

[0109] The thermal mass flow meter 7 is used to monitor the gas flow parameters flowing through the throttle valve in real time. It is installed in a sealed manner with the corresponding connection hole 21 and is in sealed connection with the gas station.

[0110] When the throttle body is installed on the positioning mold 4, the air outlet of the throttle body is connected to the connecting hole 21. When the throttle body is fixed by the fixing claw assembly 5, the air outlet of the throttle body is sealed to the connecting hole 21.

[0111] Drive motor assembly 6 includes:

[0112] Servo driver 61; Here, when operating using the above welding method, it is necessary to lock the position of valve shaft 9. At this time, when the torque jump occurs and reaches the preset torque, the valve shaft 9 is fixed with the preset torque.

[0113] The lifting base 62 is used to drive the servo drive 61 to move up and down; when it drives the servo drive 61 to lift, it can offset part of the micro-movement of the valve shaft 9 during welding.

[0114] Connector 63, installed at the power output end of servo drive 61, is used to connect to throttle valve shaft 9. The upper end of connector 63 connects to valve shaft 9, and the lower end connects to the output shaft of servo drive 61. After the throttle valve is installed and fixed, the lifting base 62 is activated to drive servo drive 61 to move upward. After connector 63 is connected to valve shaft 9, it stops moving upward and is fixed in that position. Then, servo drive 61 performs the actions according to the steps in the automatic welding method. In actual implementation, the upper end of connector 63 is usually configured with a hole that matches valve shaft 9. Considering the need for throttle valve replacement, the upper end of connector 63 can be opened as a V-shaped slot. This not only meets the need for rapid replacement during the docking process, but also enables automatic docking during its upward movement.

[0115] The core of this solution lies in its ingenious structural design, which utilizes multiple modular structures to complete the positioning, fixing, and rotation of the throttle valve shaft 9. At the same time, while fixing, the throttle valve outlet is sealed to the connection hole 21 to ensure the accuracy of the intake volume measurement data and effectively avoid inaccurate data caused by gas leaks.

[0116] like Figure 8 , 9 As shown, from one end of the installation positioning mold 4 to the end of the installation thermal mass flow meter 7, the connecting hole 21 tapers in a streamlined shape.

[0117] Considering the throttle body replacement, the connection hole 21 is designed to be streamlined to accommodate different throttle body models. The seal 3 is installed inside the connection hole 21. When the throttle body outlet is connected to the connection hole 21, it is pressed against the inner wall of the seal 3 to form a seal.

[0118] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An automatic welding method for throttle body assembly, applied to the welding of the valve shaft and sector teeth of the throttle body, wherein a valve plate is mounted on the valve shaft, characterized in that, Includes the following steps: S1. Drive the valve shaft to rotate, causing the valve plate to rotate in the throttle valve to the target opening position. At this time, the intake air volume of the throttle valve reaches the target idle speed intake air volume simulating the engine idle speed state. The target opening position of the valve plate is determined by simulating engine idling using a test air circuit, including the following steps: S11, sealing the outlet of the throttle valve with the test air circuit, and exposing the intake port to the atmosphere; S12, activating the test air circuit to simulate engine idling intake conditions; S13, driving the valve shaft to rotate and monitoring the gas flow parameters flowing through the throttle valve in real time; S131, when the gas flow parameters reach and stabilize at the preset target idling intake volume, recording the valve plate position at this time as the target opening position. S2. When the valve plate rotates to the target opening position, determine the reference position of the sector teeth; S3. Drive the valve shaft to rotate again, causing the valve plate to rotate completely in the throttle valve to the mechanical stop position, and lock it in that position; Determining that the valve shaft has fully rotated to the mechanical stop position includes the following steps: S31, driving the valve shaft to rotate forward, and monitoring the output torque of the servo motor driving the valve shaft rotation in real time; S32, when the output torque is detected to first increase and reach a preset torque, recording the position of the valve shaft at this time as the first contact position; S33, driving the servo motor to rotate in the reverse direction by a preset yield angle, while simultaneously introducing N pulse airflows into the throttle valve passage; S34, driving the valve shaft to rotate forward again until it rotates to the first contact position, and continuously monitoring the output torque. Torque; S341, If ​​the output torque increases synchronously when the first contact position is reached again, it is determined that the valve plate has fully reached the mechanical stop position and the valve shaft position is locked; S342, If the output torque does not increase synchronously, repeat the above steps S31-S34 until a torque increase that meets the requirements is stably monitored at the same position during continuous forward drive; wherein: the synchronous increase is: the output torque when the valve shaft rotates to the first contact position again is the same in magnitude and trend as the output torque recorded when it rotates to the first contact position the previous time; S4. Calculate the rotation angle θ of the valve shaft when the valve plate rotates from the target opening position to the mechanical stop position; S5. When the valve plate is fully rotated to the mechanical stop position, rotate the sector tooth according to the rotation angle θ, so that the sector tooth rotates from the reference position to the actual welding position, and weld the sector tooth and the valve shaft at the actual welding position.

2. The automatic welding method for throttle body assembly according to claim 1, characterized in that: The gas flow parameter is the volumetric flow rate or mass flow rate passing through the throttle valve under standard conditions.

3. The method of automatically welding a throttle assembly of claim 1, wherein: The target idle air volume is determined by one of the following methods: The optimal intake air volume required to maintain the target idle speed is directly obtained from the electronic control unit calibration database of the target engine. Based on the engine's displacement, compression ratio, and valve timing design parameters, the theoretical intake volume required to maintain idle speed is calculated through engine operation simulation. In engine bench tests, the actual intake volume corresponding to the engine operating at the most stable idle speed with the lowest emissions is found by adjusting the throttle opening.

4. An automatic welding system for throttle body assembly, used to implement the automatic welding method for throttle body assembly as described in any one of claims 1-3, characterized in that: include: The welding station is used to adjust the position of the sector teeth and weld them to the valve shaft. The gas station is configured to simulate engine idling and provide pulsed airflow; Throttle body clamping fixture, used for clamping and fixing the throttle body, and sealed and connected to the gas station; The control and computing unit is connected to the welding station, the gas station, and the throttle clamping fixture via signals, respectively.

5. The automatic welding system of throttle assembly as claimed in claim 4 wherein: The throttle valve clamping fixture includes: Mounting base; A vertical mounting base has a connection hole, and a sealing element is provided in the connection hole; A positioning mold is installed on one side of the base surface of the vertical mounting base; A set of fixing claw assemblies is installed on the vertical mounting base; A drive motor assembly is disposed on the mounting base below the positioning mold and is used to drive the valve shaft to rotate; A thermal mass flow meter is used to monitor the gas flow parameters passing through the throttle valve in real time. It is installed in a sealed manner corresponding to the connection hole and is in sealed communication with the gas station. When the throttle body is installed on the positioning mold, the air outlet of the throttle body is connected to the connecting hole. When the throttle body is fixed by the fixing claw assembly, the air outlet of the throttle body is sealed to the connecting hole.

6. The automatic welding system of throttle assembly as claimed in claim 5 wherein: The drive motor assembly includes: Servo driver; A lifting base is used to move the servo driver up and down; The connector, installed at the power output end of the servo driver, is used to connect to the throttle valve shaft.

7. The automatic throttle assembly welding system of claim 5, wherein: From the end where the positioning mold is installed to the end where the thermal mass flow meter is installed, the connecting hole tapers in a streamlined shape.

Images