A detection assembly system and detection assembly method for a frame bushing

Abstract

The application discloses a detection and assembly system and method for a frame bushing, which comprises a press-fitting piece, a positioning piece, a first detection piece, a second detection piece, a third detection piece and a control piece. The detection and assembly system solves the problem of separation of detection and assembly, can complete the bushing axial stiffness detection in the initial stage of press-fitting, does not need an additional detection process, greatly shortens the overall production cycle, adapts to the mass production rhythm, eliminates the quality hidden danger caused by sampling detection, prevents abnormal bushings from flowing into subsequent links, has good adaptability, the positioning ends of the positioning pieces can be close to or away from each other, can adapt to bushing outer sleeves of different sizes in combination with the support design of the guide inclined surface, does not need frequent tool replacement, reduces the equipment debugging cost, ensures the bushing assembly precision, realizes efficient, lossless and full-quantity coverage of the stiffness detection, significantly improves the production quality and efficiency of the subframe, reduces the post-production cost, and guarantees the stability of the vehicle control performance and NVH performance.

Description

Technical Field

[0001] This application relates to the field of vehicle frame assembly technology, and in particular to a vehicle frame bushing inspection and assembly system and method. Background Technology

[0002] In the automotive manufacturing industry, the subframe bushing, as a key component connecting the subframe to the body or other parts, has a crucial impact on the vehicle's handling performance and NVH (noise, vibration, and harshness) performance. It is one of the core factors determining the vehicle's driving stability, comfort, and safety. Therefore, the precise control of the subframe bushing's stiffness performance has become a key link in the automotive production process.

[0003] In the current automotive industry chain division of labor, Tier 1 suppliers of subframes generally focus on the design and production of the overall subframe structure. Most lack independent R&D and manufacturing capabilities for subframe bushings. To meet production needs, Tier 1 suppliers typically need to purchase rubber bushings developed and manufactured by Tier 2 suppliers and then assemble them onto the subframe. However, in the bushing procurement and acceptance stage, Tier 2 suppliers have significant limitations in their testing methods for the stiffness performance of the bushing rubber. This testing method is close to destructive testing. The specific process involves pressing the bushing into a specific custom-made fixture, then placing the fixture containing the bushing on an MTS stiffness performance testing platform, and applying a specific load through the testing platform to obtain the bushing stiffness data.

[0004] The existing testing technologies have several drawbacks: First, the testing process is complex and time-consuming. The process of pressing the bushings into the tooling requires precise alignment and is labor-intensive. Subsequent testing on the MTS testing platform also needs to follow specific procedures, resulting in a long single testing cycle, which is difficult to adapt to the pace of efficient production. Second, repeated pressing operations negatively impact bushing performance. The bushings are subjected to certain external forces during the pressing process into the tooling. This pressing process is not a reasonable force under actual assembly conditions. Repeated pressing can easily change the original physical state of the bushings, especially affecting the force performance of the bushings during subsequent actual assembly, which may lead to a decrease in the fit accuracy between the bushings and the subframe after assembly. Third, large-scale, large-sample testing cannot be achieved. Due to the time consumption of testing and the potential damage to the bushings, the existing testing methods can only perform sampling testing on the bushings, which cannot cover all purchased bushings. There is a risk that bushings with abnormal stiffness will not be detected and will flow into the subsequent assembly process, which may lead to substandard vehicle performance, increase rework costs and quality risks later.

[0005] Furthermore, under the existing testing model, bushing stiffness testing is independent of the subsequent assembly process. Bushings that pass the test may experience performance changes due to external factors during the transfer to the assembly station. Since stiffness verification is not performed again before assembly, this further exacerbates quality risks and affects the performance stability of the subframe and the whole vehicle after assembly. Summary of the Invention

[0006] In view of the deficiencies in the prior art, this application provides a testing and assembly system and method for chassis bushings to solve the problems of low efficiency and low reliability in the testing and assembly of chassis bushings in the prior art.

[0007] The above-mentioned objectives of this application are mainly achieved through the following technical solutions:

[0008] A testing and assembly system for vehicle frame bushings, the testing and assembly system comprising:

[0009] A press-fitting component is movably arranged on the upper part of the frame sleeve. The press-fitting component includes a press-fitting ring for contacting the top surface of the bushing outer sleeve and a press-fitting post for contacting the top surface of the bushing inner sleeve. The length of the press-fitting ring is less than the length of the press-fitting post.

[0010] A first detection element and a second detection element are connected to the press-fitting component. The first detection element can detect the displacement of the press-fitting component along the axial direction of the frame sleeve and output a displacement signal. The second detection element can detect the force acting on the press-fitting component along the radial direction of the frame sleeve and output a first force signal.

[0011] A positioning element is provided for mounting on the assembly end of the frame sleeve. The positioning element includes at least two positioning ends that can be close to or far apart from each other. The positioning ends are provided with guide ramps that can extend and support the bushing outer sleeve.

[0012] The third detection element is provided in multiple ways and correspondingly disposed on the positioning end. The third detection element can detect the force acting on the positioning end along the radial direction of the frame sleeve and output a second force signal.

[0013] The control unit is electrically connected to the first detection unit, the second detection unit, and the third detection unit, respectively, and processes the displacement signal, the first force signal, and the second force signal.

[0014] In an optional embodiment, a first driving member is connected to the press-fit component, which can drive the press-fit component to move axially along the frame sleeve.

[0015] In an optional embodiment, the first driving member is a pneumatic pressing mechanism or a hydraulic pressing mechanism.

[0016] In an optional embodiment, each of the positioning ends is connected to a second driving member, which can drive the positioning end to move radially along the frame sleeve.

[0017] In an optional embodiment, the second driving component includes a worm gear and a worm wheel that are connected in a transmission. The worm gear is arranged radially along the frame sleeve. A slider is fixedly provided at one end of the worm gear. A slide rail is supported at the lower part of the slider. An elastic element is provided between the slider and the positioning end. The third detection element is provided between the elastic element and the slider.

[0018] In an optional embodiment, the outer diameter of the press-fit column is not greater than the outer diameter of the inner sleeve of the bushing.

[0019] In an optional embodiment, the inner diameter of the press-fit ring is not less than the inner diameter of the bushing outer tube and not greater than the outer diameter of the bushing outer tube.

[0020] In an optional embodiment, the length of the press-fit ring is 8-12 mm shorter than the length of the press-fit column.

[0021] Based on the same inventive concept, this application also provides a method for inspecting and assembling a frame bushing, wherein the method is applied to the above-mentioned inspection and assembly system, and the method includes:

[0022] Arrange the positioning components and keep the positioning ends extending to the assembly end of the frame sleeve, and adjust the distance between the positioning ends to be smaller than the inner diameter of the frame sleeve;

[0023] Arrange the press-fit component and reserve assembly space for the frame bushing between the press-fit component and the frame sleeve;

[0024] Remove the frame bushing and place it on the multiple positioning ends;

[0025] Start pressing the press-fit component down onto the frame bushing, while simultaneously applying a thrust along the radial direction of the frame sleeve to the positioning end, and continuously recording the displacement signal, the first force signal, and the second force signal;

[0026] The difference L between the length of the press-fit ring and the length of the press-fit column is used to obtain the force F corresponding to the second force signal when the distance corresponding to the displacement signal is L, and to calculate the bushing stiffness data K, K = F / L;

[0027] Compare the bushing stiffness data with a preset range. If the bushing stiffness data is outside the preset range, mark the frame bushing as a defective part. If the bushing stiffness data is within the preset range, mark the frame bushing as a qualified part, and the test is completed.

[0028] Continue operating the pressing component to press down on the qualified component. The qualified component is pressed down and squeezes the positioning end away from each other until the qualified component is pressed to the target depth of the frame sleeve, thus completing the assembly.

[0029] In an optional embodiment, the thrust applied to the positioning end is less than the downward force applied to the press-fitting component, so that when the downward pressing distance of the press-fitting component is greater than L, the press-fitting component presses down on the qualified part and squeezes the positioning ends to separate from each other until the qualified part enters the frame sleeve.

[0030] Compared with the prior art, the advantages of this application are:

[0031] The inspection and assembly system of this application is used for the inspection and assembly of frame bushings. The system includes a press-fit component, a positioning component, a first inspection component, a second inspection component, a third inspection component, and a control component. The press-fit component is movably arranged on the upper part of the frame bushing. The press-fit component includes a press-fit ring for contacting the top surface of the outer bushing and a press-fit post for contacting the top surface of the inner bushing. The length of the press-fit ring is less than the length of the press-fit post. The first and second inspection components are connected to the press-fit component. The first inspection component measures the displacement of the press-fit component along the axial direction of the frame bushing and outputs a displacement signal. The second inspection component detects the force exerted on the press-fit component along the axial direction of the frame bushing. The frame sleeve experiences radial force and outputs a first force signal; a positioning element is arranged on the assembly end of the frame sleeve, the positioning element includes at least two positioning ends that can be close to or far from each other, the positioning end is provided with a guide slope, the guide slope can extend and support under the bushing outer tube; multiple third detection elements are provided and correspondingly arranged on the positioning ends, the third detection elements can detect the radial force applied to the positioning end along the frame sleeve and output a second force signal; a control element is electrically connected to the first detection element, the second detection element and the third detection element respectively, and processes the displacement signal, the first force signal and the second force signal.

[0032] To address the problems of existing subframe bushing inspection and assembly being separated, time-consuming, prone to bushing damage, and unable to achieve full-scale inspection, this inspection and assembly system enables simultaneous bushing stiffness inspection and assembly. The press-fit component is located on the upper part of the frame bushing. The press-fit ring and press-fit post respectively contact the top surfaces of the outer and inner bushings of the bushing, with the press-fit ring being shorter than the press-fit post to ensure pressure is applied to the inner bushing first during the press-fit process. The first and second inspection components are connected to the press-fit component, respectively detecting the axial displacement and radial force of the press-fit component. The third inspection component is positioned on the positioning end of the positioning component, detecting the radial force on the positioning end. The positioning component is arranged at the assembly end of the frame bushing, with at least two openable positioning ends supporting the outer bushing of the bushing via guide ramps. This achieves bushing positioning and allows for adaptation to bushings of different sizes through the movement of the positioning ends. The control component is electrically connected to all inspection components, receiving and processing displacement and force signals in real time to achieve coordinated inspection and assembly operations.

[0033] At the start of assembly inspection, the positioning ends of the positioning components first approach each other, using the guide ramp to support the bushing outer tube. During this process, the third detection component detects the radial force on the positioning end in real time and outputs a second force signal. The control component uses this signal to determine the initial positioning state of the bushing outer tube, avoiding forced alignment damage during traditional tooling press-fitting. The press-fit component moves downward along the axial direction of the frame sleeve. Since the press-fit ring is shorter than the press-fit post, the press-fit post will first contact the top surface of the inner bushing sleeve and apply axial pressure. At this time, the second detection component detects the axial displacement of the press-fit component, and the first detection component detects the radial force on the press-fit component. The displacement signals output by both are transmitted synchronously to the control component along with the first force signal. The control component analyzes the displacement... The correspondence between quantity and radial force allows for real-time calculation of the bushing's axial stiffness. When the press-fitting column pushes the inner sleeve downwards, the bushing rubber body deforms. The radial force change captured by the first detection component and the displacement change captured by the second detection component form the key parameters for stiffness calculation. Unlike the traditional method, there is no need to press the bushing into a special tooling and then transfer it to the testing table, completely eliminating the need for repeated press-fitting steps. If the control component analysis finds that the displacement and force relationship exceeds the preset threshold (i.e., abnormal stiffness), the press-fitting action will be stopped immediately and the part will be identified as a problem part and promptly removed. Qualified bushings can continue to be pushed by the press-fitting component after the inspection is completed until they are completely pressed into the frame sleeve. The entire process can be completed without interruption, integrating the inspection into the assembly process.

[0034] This inspection and assembly system solves the problem of separating inspection and assembly. It can complete the bushing axial stiffness test at the initial pressing stage, eliminating the need for additional inspection procedures, significantly shortening the overall production cycle and adapting to mass production pace. It avoids damage to the bushing caused by repeated pressing; the system achieves inspection and assembly simultaneously through a single pressing action of the pressing component. Furthermore, the positioning component flexibly supports the bushing via a guide ramp, eliminating the need for forced pressing tooling, effectively protecting the bushing's original physical state and ensuring stable performance in subsequent assembly. It completely eliminates quality risks associated with sampling inspection, preventing abnormal bushings from flowing into subsequent stages. Moreover, it has excellent adaptability; the positioning ends of the positioning components can move closer or further apart, and combined with the support design of the guide ramp, it can adapt to bushing outer tubes of different sizes, eliminating the need for frequent tooling changes and reducing equipment debugging costs. It offers higher inspection accuracy; the first, second, and third inspection components capture the displacement, radial force of the pressing component, and radial force of the positioning end, respectively. Multi-dimensional data is comprehensively analyzed by the control components, accurately reflecting the bushing stiffness characteristics and avoiding misjudgments caused by a single inspection dimension. Ultimately, this testing and assembly system can achieve efficient, non-destructive, and full-coverage stiffness testing while ensuring the accuracy of bushing assembly. This significantly improves the production quality and efficiency of subframes, reduces rework costs, and ensures the stability of the vehicle's handling performance and NVH performance. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the structure of the inspection and assembly system during operation, as provided in the embodiments of this application.

[0037] Figure 2 This is a schematic diagram of the structure at the second driving component provided in an embodiment of this application;

[0038] Figure 3 A flowchart of the testing and assembly method provided in the embodiments of this application;

[0039] In the diagram: 100, press-fit component; 101, press-fit ring; 102, press-fit column; 201, first inspection component; 202, second inspection component; 203, third inspection component; 301, positioning end; 302, guide ramp; 401, first driving component; 402, second driving component; 501, worm gear; 502, worm wheel; 503, slider; 504, slide rail; 505, elastic component; 701, bushing outer sleeve; 702, bushing inner sleeve; 703, frame sleeve. Detailed Implementation

[0040] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that the description of these embodiments is intended to aid in understanding the invention, but does not constitute a limitation thereof. The specific structural and functional details disclosed herein are merely for describing exemplary embodiments of the invention. However, the invention can be embodied in many alternative forms and should not be construed as being limited to the embodiments described herein.

[0041] like Figure 1 , Figure 2 As shown, Figure 1 This is a schematic diagram of the structure of the inspection and assembly system during operation, as provided in the embodiments of this application. Figure 2 This is a schematic diagram of the structure of the second driving component 402 provided in an embodiment of this application.

[0042] A testing and assembly system for a vehicle frame bushing, the system comprising a press-fit component 100, a positioning component, a first testing component 201, a second testing component 202, a third testing component 203, and a control component, wherein:

[0043] like Figure 1 , Figure 2 As shown, the press-fitting component 100 is movably arranged on the upper part of the frame sleeve 703. The press-fitting component 100 includes a press-fitting ring 101 for contacting the top surface of the bushing outer sleeve 701 and a press-fitting post 102 for contacting the top surface of the bushing inner sleeve 702. The length of the press-fitting ring 101 is less than the length of the press-fitting post 102.

[0044] like Figure 1 As shown, the press-fit component 100 is movably arranged directly above the frame sleeve 703. The length difference between the press-fit ring 101 and the press-fit column 102 ensures that when the press-fit component 100 moves downward, the press-fit column 102 can preferentially contact the top surface of the inner sleeve 702 of the bushing, reserving an independent force application stage for subsequent stiffness testing, and avoiding interference of the outer sleeve's stress on the test data.

[0045] like Figure 1 As shown, the first detection element 201 and the second detection element 202 are connected to the pressing component 100. The first detection element 201 can detect the displacement of the pressing component 100 along the axial direction of the frame sleeve 703 and output a displacement signal. The second detection element 202 can detect the radial force acting on the pressing component 100 along the frame sleeve 703 and output a first force signal.

[0046] like Figure 1As shown, the first detection element 201 and the second detection element 202 are connected to the pressing component 100. The first detection element 201 can be a displacement sensor. When the pressing component 100 moves axially along the frame sleeve 703, the first detection element 201 can capture the displacement change in real time and output a continuous displacement signal, ensuring the accuracy of the displacement data. The second detection element 202 is a pressure sensor, which can directly detect the reaction force experienced by the pressing component 100 during the pushing of the frame sleeve 703. It can convert the force signal into an electrical signal and output a first force signal, providing reliable force data for stiffness calculation. It is worth noting that the installation positions of the first detection element 201 and the second detection element 202 have been optimized through mechanical analysis to avoid the impact of vibration generated during the movement of the pressing component 100 on the detection accuracy. Furthermore, the signal output terminals of both are connected to the control component through shielded cables to reduce external electromagnetic interference.

[0047] The positioning element is used to be arranged on the assembly end of the frame sleeve 703. The positioning element includes at least two positioning ends 301 that can be close to or far apart from each other. The positioning ends 301 are provided with guide ramps 302, which can extend and support under the bushing outer sleeve 701.

[0048] like Figure 1 , Figure 2 As shown, each positioning end 301 is machined with a guide slope 302. The inclination angle of the guide slope 302 can ensure that the bushing outer tube 701 is stably supported when it is placed, and can also compress the positioning ends 301 away from each other when the bushing outer tube is pressed down.

[0049] The third detection element 203 is provided in multiple ways and is correspondingly disposed on the positioning end 301. The third detection element 203 can detect the radial force acting on the positioning end 301 along the frame sleeve 703 and output a second force signal.

[0050] like Figure 1 , Figure 2 As shown, the third detection element 203 can directly detect the radial pressure applied by the bushing outer tube 701 to the positioning end 301 along the frame tube 703 and output a second force signal. Considering the possible roundness error of the bushing, the number of positioning ends 301 on the positioning element is preferably three, and they are evenly distributed at 120°. The second force signals output by the three third detection elements 203 can be compared. If the difference between any two signals exceeds a preset threshold (such as 5%), the control element can determine that there is a shape deviation in the bushing and issue an early warning in time, further improving the comprehensiveness of the detection.

[0051] The control unit (not shown in the figure) is electrically connected to the first detection unit 201, the second detection unit 202 and the third detection unit 203 respectively, and processes the displacement signal, the first force signal and the second force signal.

[0052] The control unit, as the core processing unit of the system, is electrically connected to the first detection unit 201, the second detection unit 202, and the third detection unit 203 respectively. It can perform preprocessing such as filtering and amplification on the received displacement signal, the first force signal, and the second force signal to eliminate signal noise. The controller has a built-in stiffness calculation algorithm, which can calculate the axial stiffness value of the bushing based on the displacement change output by the second detection unit 202 and the force change output by the first detection unit 201, and compare the calculation result with the preset stiffness qualified range to complete the detection operation.

[0053] The inspection and assembly system of this application is used for the inspection and assembly of frame bushings. The system includes a pressing component 100, a positioning component, a first inspection component 201, a second inspection component 202, a third inspection component 203, and a control component. The pressing component 100 is movably arranged on the upper part of the frame bushing 703. The pressing component 100 includes a pressing ring 101 for contacting the top surface of the outer bushing 701 and a pressing post 102 for contacting the top surface of the inner bushing 702. The length of the pressing ring 101 is less than the length of the pressing post 102. The first inspection component 201 and the second inspection component 202 are connected to the pressing component 100. The first inspection component 201 measures the displacement of the pressing component 100 along the axial direction of the frame bushing 703 and outputs a displacement signal. The second inspection component 202 detects the displacement of the pressing component 100. The component 100 is subjected to a radial force along the frame sleeve 703 and outputs a first force signal; the positioning component is arranged on the assembly end of the frame sleeve 703, the positioning component includes at least two positioning ends 301 that can be close to or far from each other, the positioning end 301 is provided with a guide slope 302, the guide slope 302 can extend and support under the bushing outer sleeve 701; a plurality of third detection components 203 are provided and correspondingly arranged on the positioning ends 301, the third detection components 203 can detect the radial force along the frame sleeve 703 applied to the positioning end 301 and output a second force signal; the control component is electrically connected to the first detection component 201, the second detection component 202 and the third detection component 203 respectively, and processes the displacement signal, the first force signal and the second force signal.

[0054] To address the problems of existing subframe bushing testing and assembly being separated, time-consuming testing, easy damage to bushings, and inability to achieve full-scale testing, this testing and assembly system enables bushing stiffness testing and assembly to be performed simultaneously. The press-fit component 100 is located on the upper part of the frame sleeve 703. The press-fit ring 101 and the press-fit post 102 respectively contact the top surfaces of the bushing outer sleeve 701 and the inner sleeve. The length of the press-fit ring 101 is shorter than that of the press-fit post 102, ensuring that pressure can be applied to the inner sleeve 702 of the bushing first during the press-fitting process. The first detection component 201 and the second detection component 202 are connected to the press-fit component 100 to detect the axial displacement and radial force of the press-fit component 100, respectively. The third detection component 203 is correspondingly set on the positioning end 301 of the positioning component to detect the radial force on the positioning end 301. The positioning component is arranged at the assembly end of the frame sleeve 703. Its at least two openable positioning ends 301 support the bushing outer sleeve 701 through the guide slope 302, which can realize the bushing positioning and adapt to different sizes of bushings by moving the positioning ends 301. The control component is electrically connected to all detection components, receives and processes displacement and force signals in real time, and realizes the coordinated operation of detection and assembly.

[0055] At the start of assembly inspection, the positioning ends 301 of the positioning components move closer together, using the guide ramp 302 to support the bushing outer sleeve 701. During this process, the third detection component 203 detects the radial force on the positioning end 301 in real time and outputs a second force signal. The control component uses this signal to determine the initial positioning state of the bushing outer sleeve 701, avoiding forced alignment damage during traditional tooling press-fitting. The press-fit component 100 moves axially downward along the frame sleeve 703. Since the length of the press-fit ring 101 is shorter than that of the press-fit post 102, the press-fit post 102 will first contact the top surface of the bushing inner sleeve 702 and apply axial pressure. At this time, the second detection component 202 detects the axial displacement of the press-fit component 100, and the first detection component 201 detects the radial force on the press-fit component 100. The displacement signals output by both are the same as the first force signal. The data is transmitted to the control unit. By analyzing the correspondence between displacement and radial force, the control unit can calculate the axial stiffness of the bushing in real time. When the pressing column 102 pushes the inner sleeve downward, the bushing rubber body deforms. The radial force change captured by the first detection element 201 and the displacement change captured by the second detection element 202 form the key parameters for stiffness calculation. Unlike the traditional method, there is no need to press the bushing into a special tooling and then transfer it to the testing table, completely eliminating the repeated pressing steps. If the control unit analysis finds that the displacement and force relationship exceeds the preset threshold (i.e., abnormal stiffness), it will immediately stop the pressing action and determine it as a problem part, and remove it in time. The qualified bushing can continue to be pushed by the pressing element 100 after the test is completed until it is completely pressed into the frame sleeve 703. The whole process does not need to be interrupted, integrating the test into the assembly process.

[0056] This inspection and assembly system solves the problem of separating inspection and assembly. It can complete the bushing axial stiffness test at the initial pressing stage, eliminating the need for additional inspection procedures, significantly shortening the overall production cycle and adapting to mass production pace. It avoids damage to the bushing caused by repeated pressing; the system achieves inspection and assembly simultaneously through a single pressing action of the pressing component 100. Furthermore, the positioning component flexibly supports the bushing via the guide slope 302, eliminating the need for forced pressing fixtures, effectively protecting the bushing's original physical state and ensuring stable performance during subsequent assembly. It completely eliminates quality risks associated with sampling inspections. Abnormal bushings are prevented from flowing into subsequent stages; moreover, it has good adaptability, with the positioning ends 301 of the positioning components moving closer or further apart. Combined with the support design of the guide slope 302, it can accommodate bushing outer tubes 701 of different sizes, eliminating the need for frequent tooling changes and reducing equipment debugging costs. The detection accuracy is higher; the first, second, and third detection components 203 respectively capture the displacement of the press-fit component 100, radial force, and radial force of the positioning end 301. Multi-dimensional data is comprehensively analyzed by the control components to accurately reflect the bushing stiffness characteristics, avoiding misjudgments caused by a single detection dimension. Ultimately, this inspection and assembly system can achieve efficient, non-destructive, and full-coverage stiffness testing while ensuring bushing assembly accuracy, significantly improving the production quality and efficiency of subframes, reducing later rework costs, and ensuring the stability of the vehicle's handling performance and NVH performance.

[0057] like Figure 1 , Figure 2 As shown, in an optional embodiment, a first driving member 401 is connected to the press-fit member 100, and the first driving member 401 can drive the press-fit member 100 to move axially along the frame sleeve 703.

[0058] The first drive component 401 solves the problems of movement accuracy and power output stability of the press-fit component 100. The first drive component 401 and the press-fit component 100 can be connected by a floating joint, which can compensate for the coaxiality deviation between the press-fit component 100 and the frame sleeve 703, avoid uneven pressing force due to installation errors, and thus protect the bushing and the structure of the press-fit component 100 itself. The output end of the first drive component 401 can also integrate a pressure adjustment module, which can preset different upper limits of driving pressure according to the material characteristics of the bushing (such as rubber hardness and metal sleeve thickness) to prevent excessive deformation of the bushing or damage to the inner sleeve due to excessive pressure. The movement speed of the drive component can be adjusted in real time by the controller. The speed is low during the detection stage (when the press-fit column 102 contacts the inner sleeve) to ensure the accuracy of displacement and force signal acquisition. The speed is increased in the later stage of assembly (when the press-fit ring 101 contacts the outer sleeve) to balance detection accuracy and assembly efficiency.

[0059] like Figure 1 , Figure 2As shown, in an optional embodiment, the first driving component 401 is a pneumatic pressing mechanism or a hydraulic pressing mechanism. In order to provide a stable and reliable driving effect, it can also be replaced by a servo motor.

[0060] Choosing a pneumatic pressing mechanism offers advantages such as fast response, low cost, and no oil pollution, making it particularly suitable for the assembly of bushings in new energy vehicles where cleanliness requirements are high. Conversely, a hydraulic pressing mechanism is suitable for large-size, high-rigidity heavy-duty vehicle bushings, such as commercial vehicle subframe bushings, which require greater pressing force to complete assembly. The high thrust of the hydraulic mechanism ensures the bushing is smoothly pressed into the frame sleeve 703, while the hydraulic locking valve enables instantaneous positioning of the pressed component 100, facilitating displacement stability during the testing phase and improving the accuracy of stiffness calculations.

[0061] like Figure 1 , Figure 2 As shown, in an optional embodiment, each of the positioning ends 301 is connected to a second driving member 402, which can drive the positioning end 301 to move radially along the frame sleeve 703.

[0062] To improve the adaptability and movement accuracy of the positioning end 301 to bushings of different specifications and avoid the problem of frequent tooling changes required by traditional fixed positioning structures, the second drive component 402 and the positioning end 301 are modularly connected for easy maintenance and replacement. Each second drive component 402 is independently controlled by the control component, enabling synchronous or asynchronous movement of the positioning end 301. For example, when the bushing outer tube 701 has a slight ellipticity, the control component can drive a single positioning end 301 to make fine adjustments based on the force signal from the third detection component 203, compensating for the shape deviation of the outer tube and ensuring the uniformity of the supporting force of the three positioning ends 301 on the bushing, thereby avoiding detection errors caused by bushing tilt. In addition, the output end of the second drive component 402 is equipped with a travel limit switch. When the positioning end 301 moves to the maximum or minimum travel, the limit switch triggers a signal to the control component to prevent excessive movement of the positioning end 301 from causing structural collisions and to protect the transmission components.

[0063] like Figure 1 , Figure 2 As shown, in an optional embodiment, the second driving member 402 includes a worm gear 501 and a worm wheel 502 that are connected in a transmission manner. The worm gear 501 is arranged radially along the frame sleeve 703. A slider 503 is fixedly provided at one end of the worm gear 501. A slide rail 504 is supported at the lower part of the slider 503. An elastic member 505 is provided between the slider 503 and the positioning end 301. The third detection member 203 is provided between the elastic member 505 and the slider 503.

[0064] Utilizing the self-locking characteristics of the worm gear 501 and worm wheel 502, mechanical locking can be achieved after the positioning end 301 moves to the target position, preventing the positioning end 301 from shifting due to power failure or external interference, ensuring the positioning stability of the bushing during inspection and assembly, and enabling precise adjustment of the support position of the positioning end 301; the cooperation between the slider 503 and the slide rail 504 adopts a high-precision linear guide to ensure the straightness of the radial movement of the positioning end 301, and the slide rail 504 is marked with scale lines for easy reference of adjustment distance; the elastic element 505 can be arranged as a spring assembly, which has stable stiffness and deformation. With the controllable quantity feature, when the bushing outer tube 701 contacts the positioning end 301, the elastic element 505 can generate a certain amount of compression to buffer the contact impact force and avoid scratches on the outer surface of the bushing; while the third detection element 203 is set between the elastic element 505 and the slider 503, which can directly detect the compression force of the elastic element 505. This force value is linearly related to the radial pressure of the bushing on the positioning end 301. Compared with directly contacting the detection element with the positioning end 301, it can effectively avoid the influence of friction on the detection accuracy when the positioning end 301 moves, and make the second force signal more accurately reflect the actual force state.

[0065] like Figure 1 , Figure 2 As shown, in an optional embodiment, the outer diameter of the press-fitting column 102 is not greater than the outer diameter of the inner sleeve 702. This allows the end face of the press-fitting column 102 to completely fit the top surface of the inner sleeve, ensuring that the pressure is evenly distributed across the entire end face of the inner sleeve. This guarantees that the bushing rubber body is subjected to uniform stress, and the deformation conforms to the actual working condition, thereby improving the accuracy of the stiffness test data.

[0066] In an optional embodiment, the inner diameter of the press-fit ring 101 is not less than the inner diameter of the bushing outer tube 701, and not greater than the outer diameter of the bushing outer tube 701. This balances the positioning and pressure transmission effects of the press-fit ring 101 on the bushing outer tube 701, allowing the inner edge of the press-fit ring 101 to avoid the inner wall of the outer tube, while its end face can cover a larger area of ​​the top surface of the outer tube. This ensures that the assembly pressure is evenly transmitted to the outer tube, pushing the bushing smoothly into the frame sleeve 703.

[0067] like Figure 1 , Figure 2As shown, in an optional embodiment, the length of the press-fit ring 101 is 8-12 mm shorter than the length of the press-fit column 102. This is to precisely control the separation timing between the detection and assembly stages. If the length difference is less than 8 mm, the time interval between the press-fit ring 101 and the press-fit column 102 contacting the bushing is too short, and the control component may not be able to complete the stiffness calculation before the press-fit ring 101 contacts the outer sleeve, resulting in the detection data including force interference from the outer sleeve. If the length difference is greater than 12 mm, the displacement of the inner sleeve pushed by the press-fit column 102 alone is too large, which may cause excessive stretching of the bushing rubber body, affecting its original performance. A length difference of 8-12 mm ensures that the press-fit column 102 pushes the inner sleeve. After the inner sleeve moves down, the pressing ring 101 begins to contact the outer sleeve. Within this displacement range, the deformation of the bushing rubber body is in the linear elastic stage, and the stiffness calculation results are stable and reliable, while not exceeding the elastic limit of the rubber. For example, when the pressing part 100 moves down at a speed of 10 mm / s, the 10 mm length difference can provide 1 second of independent detection time. The control component has sufficient time to complete the acquisition, calculation and qualification judgment of displacement and force signals, ensuring that bushings with abnormal stiffness are accurately screened before the assembly stage begins, avoiding subsequent rework.

[0068] like Figure 1 , Figure 2 as well as Figure 3 As shown, where Figure 3 A flowchart of a testing and assembly method provided in this application embodiment; a testing and assembly method for a frame bushing, the testing and assembly method being applied to the above-mentioned testing and assembly system, the testing and assembly method comprising:

[0069] Arrange the positioning components and keep the positioning end 301 extending to the assembly end of the frame sleeve 703, and adjust the distance between the positioning ends 301 to be smaller than the inner diameter of the frame sleeve 703.

[0070] Arrange the press-fit component 100, and reserve assembly space for the frame bushing between the press-fit component 100 and the frame sleeve 703;

[0071] Take the frame bushing and place it on the multiple positioning ends 301 and let it stand still;

[0072] The press-fit component 100 is pressed down onto the frame bushing, while a thrust is applied radially to the positioning end 301 along the frame sleeve 703, and the displacement signal, the first force signal, and the second force signal are continuously recorded.

[0073] The difference L between the length of the press-fit ring 101 and the length of the press-fit column 102 is used to obtain the force F corresponding to the second force signal when the distance corresponding to the displacement signal is L, and to calculate the bushing stiffness data K, K = F / L;

[0074] Compare the bushing stiffness data with a preset range. If the bushing stiffness data is outside the preset range, mark the frame bushing as a defective part. If the bushing stiffness data is within the preset range, mark the frame bushing as a qualified part, and the test is completed.

[0075] Continue operating the pressing component 100 to press down on the qualified component. The qualified component is pressed down and squeezes the positioning end 301 away from each other until the qualified component is pressed to the target depth of the frame sleeve 703, thus completing the assembly.

[0076] The positioning components need to be aligned using tooling fixtures to ensure that the supporting surfaces of the positioning ends 301 are on the same horizontal plane, thus avoiding misalignment of the bushing after placement due to tilting of the positioning components. When adjusting the spacing of the positioning ends 301, the initial spacing is preset according to the outer diameter of the bushing outer tube 701 to be assembled. For example, when the outer diameter of the bushing outer tube 701 is 50mm, the initial spacing between the positioning ends 301 is set to 45-48mm to provide stable support for the bushing and to reserve space for the positioning ends 301 to move outward later.

[0077] The arrangement of the press-fit component 100 needs to be calibrated to ensure coaxiality with the frame sleeve 703, so as to ensure that the deviation between the axis of the press-fit ring 101 and the axis of the press-fit column 102 and the axis of the frame sleeve 703 does not exceed the preset range, and to avoid damage to the bushing by the off-center load during the press-fitting process. The height of the reserved assembly space needs to be set comprehensively based on the overall height of the bushing (e.g., the bushing height is 30mm) and the pre-press stroke of the press-fit column 102 (e.g., 5mm). Usually, the reserved height is 35-40mm, which not only makes it easier for operators or automated robotic arms to place the bushing stably on the positioning end 301, but also shortens the initial downward distance of the press-fit component 100 and improves efficiency.

[0078] The bushing must be placed in a way that ensures the bottom surface of its outer sleeve 701 contacts the guide slope 302 of all positioning ends 301. The settling time is set to 2-3 seconds. On the one hand, this allows the bushing to stabilize under its own weight, eliminating the impact of momentary shaking during placement on positioning accuracy. On the other hand, it allows the third detection element 203 to collect the initial force signal after the bushing has settled. The control element will store this initial force signal as a reference value. The force signal in subsequent detection stages must be subtracted from this reference value to ensure the accuracy of stiffness calculation.

[0079] When the pressing component 100 is pressed down, the first driving component 401 outputs downward pressure smoothly at a preset speed. The pressing column 102 first contacts the top surface of the inner sleeve 702 of the bushing and gradually applies pressure. During this process, the second detection component 202 records the axial displacement of the pressing component 100, and the first detection component 201 simultaneously records the radial reaction force (i.e., the force generated by the deformation of the bushing rubber body) on the pressing column 102. At the same time, the second driving component 402 applies a radial thrust to the positioning end 301. This thrust is transmitted to the outer sleeve 701 of the bushing through the positioning end 301, ensuring that the outer sleeve 701 of the bushing is stably supported by the positioning end 301, and preventing the positioning end 301 from shifting laterally when the pressing column 102 is pressed down. A dynamic curve of displacement and force is formed. The control component judges whether the detection process is stable by the smoothness of the curve. If the curve changes abruptly (such as the force increasing by more than 10% instantaneously), it is judged that there may be internal defects in the bushing (such as rubber bubbles), and the pressing is immediately stopped and the abnormality is marked.

[0080] The length difference L needs to be determined based on the actual dimensions of the press-fit ring 101 and the press-fit column 102 (such as the aforementioned range of 8-12mm). When the press-fit ring 101 has not yet contacted the bushing outer tube 701, the force F collected by the first detection component 201 is entirely generated by the deformation of the bushing rubber body, without any other external force interference. The control component calculates the stiffness K through the built-in algorithm. The control component will make a preliminary comparison between the calculated K value and the preset stiffness range of the bushing of this model, providing data support for subsequent qualification judgment.

[0081] The preset range needs to be set comprehensively based on the vehicle performance requirements, bushing material characteristics and industry standards. The control unit supports modifying the preset range via touch screen to adapt to the needs of different vehicle models. When marking a problem part, the control unit records the detection data of the frame sleeve 703 and drives the press-fit part 100 to move upward and reset. The positioning end 301 remains stationary, making it easy for the operator to transfer the problem part.

[0082] After marking the qualified part, the pressing part 100 continues to press down according to the assembly stage parameters. Under the thrust of the pressing column 102, the qualified part moves downward, and its bushing outer tube 701 pushes the guide slope 302 of the positioning end 301, so that the positioning end 301 overcomes the radial thrust of the second driving part 402 and moves outward along the slide rail 504. The control part monitors the pressing depth of the qualified part through the displacement signal of the second detection part 202. The target depth needs to be determined according to the design size of the frame sleeve 703. When the displacement reaches the requirement, it is judged that the qualified part has been pressed into place.

[0083] In an optional embodiment, the thrust applied to the positioning end 301 is less than the downward pressure applied to the pressing member 100, so that when the downward pressing distance of the pressing member 100 is greater than L, the pressing member 100 presses down on the qualified part and squeezes the positioning end 301 to separate from each other until the qualified part enters the frame sleeve 703.

[0084] By properly matching the thrust and downward pressure, a seamless connection is achieved between the stable positioning of the bushing during the testing phase and the automatic avoidance of the positioning end 301 during the assembly phase. Specifically, the thrust setting of the positioning end 301 needs to comprehensively consider the strength and positioning stability of the bushing outer tube 701, and the downward pressure should be 1.2-2 times this thrust. This ensures that the bushing remains stable and does not shift during the testing phase (downward pressure distance not greater than L), and is easily overcome by the downward force of the qualified part during the assembly phase (downward pressure distance greater than L), allowing the positioning end 301 to separate smoothly outward. If the thrust is too large, the positioning end 301 will not be able to separate, and the qualified part will not be able to enter the frame sleeve 703, causing assembly jamming. If the thrust is too small, the bushing is prone to shifting during the testing phase, affecting the testing accuracy.

[0085] It should be understood that the terms "first," "second," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance. Although the terms "first," "second," etc., may be used herein to describe various units, these units should not be limited by these terms. These terms are only used to distinguish one unit from another. For example, a first unit may be referred to as a second unit, and similarly, a second unit may be referred to as a first unit, without departing from the scope of the exemplary embodiments of the invention.

[0086] It should be understood that the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist simultaneously. The term " / and" in this article describes another relationship between related objects, indicating that two relationships can exist. For example, A / and B can mean: A exists alone, and A and B exist alone. In addition, the character " / " in this article generally indicates that the related objects before and after it are in an "or" relationship.

[0087] It should be understood that in the description of this invention, the terms "upper," "vertical," "inner," "outer," etc., indicate the orientation or positional relationship as commonly placed when the disclosed product is used, or the orientation or positional relationship commonly understood by those skilled in the art. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0088] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0089] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the invention. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” “containing,” and / or “including” as used herein specify the presence of the stated features, integers, steps, operations, units, and / or components, and do not exclude the presence or addition of one or more other features, quantities, steps, operations, units, components, and / or combinations thereof.

[0090] Specific details are provided in the following description to provide a complete understanding of the exemplary embodiments. However, those skilled in the art will understand that the exemplary embodiments can be implemented without these specific details. In other embodiments, well-known processes, structures, and techniques may be omitted in the depiction of non-essential details to avoid obscuring the exemplary embodiments.

[0091] The above are merely specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

[0092] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art.

Claims

1. A testing and assembly system for vehicle frame bushings, characterized in that, The testing and assembly system includes: A press-fitting component is movably arranged on the upper part of the frame sleeve. The press-fitting component includes a press-fitting ring for contacting the top surface of the bushing outer sleeve and a press-fitting post for contacting the top surface of the bushing inner sleeve. The length of the press-fitting ring is less than the length of the press-fitting post. A first detection element and a second detection element are connected to the press-fitting component. The first detection element can detect the displacement of the press-fitting component along the axial direction of the frame sleeve and output a displacement signal. The second detection element can detect the force acting on the press-fitting component along the radial direction of the frame sleeve and output a first force signal. A positioning element is provided for mounting on the assembly end of the frame sleeve. The positioning element includes at least two positioning ends that can be close to or far apart from each other. The positioning ends are provided with guide ramps that can extend and support the bushing outer sleeve. The third detection element is provided in multiple ways and correspondingly disposed on the positioning end. The third detection element can detect the force acting on the positioning end along the radial direction of the frame sleeve and output a second force signal. The control unit is electrically connected to the first detection unit, the second detection unit, and the third detection unit, respectively, and processes the displacement signal, the first force signal, and the second force signal.

2. The inspection and assembly system for the frame bushing as described in claim 1, characterized in that: The press-fit component is connected to a first driving component, which can drive the press-fit component to move axially along the frame sleeve.

3. The inspection and assembly system for the frame bushing as described in claim 2, characterized in that: The first driving component is a pneumatic pressing mechanism or a hydraulic pressing mechanism.

4. The inspection and assembly system for the frame bushing as described in claim 1, characterized in that: Each of the positioning ends is connected to a second driving member, which can drive the positioning end to move radially along the frame sleeve.

5. The inspection and assembly system for the frame bushing as described in claim 4, characterized in that: The second driving component includes a worm gear and a worm wheel that are connected in transmission. The worm gear is arranged radially along the frame sleeve. A slider is fixedly provided at one end of the worm gear. A slide rail is supported at the lower part of the slider. An elastic element is provided between the slider and the positioning end. The third detection element is provided between the elastic element and the slider.

6. The inspection and assembly system for the frame bushing as described in claim 1, characterized in that: The outer diameter of the press-fit column is not greater than the outer diameter of the inner sleeve of the bushing.

7. The inspection and assembly system for the frame bushing as described in claim 6, characterized in that: The inner diameter of the press-fit ring is not less than the inner diameter of the bushing outer tube and not greater than the outer diameter of the bushing outer tube.

8. The inspection and assembly system for the frame bushing as described in claim 1, characterized in that: The length of the press-fit ring is 8-12 mm shorter than the length of the press-fit column.

9. A method for inspecting and assembling a vehicle frame bushing, characterized in that, The inspection assembly method is applied to the inspection assembly system as described in any one of claims 1-8, and the inspection assembly method includes: Arrange the positioning components and keep the positioning ends extending to the assembly end of the frame sleeve, and adjust the distance between the positioning ends to be smaller than the inner diameter of the frame sleeve; Arrange the press-fit component and reserve assembly space for the frame bushing between the press-fit component and the frame sleeve; Remove the frame bushing and place it on the multiple positioning ends; Start pressing the press-fit component down onto the frame bushing, while simultaneously applying a thrust along the radial direction of the frame sleeve to the positioning end, and continuously recording the displacement signal, the first force signal, and the second force signal; The difference L between the length of the press-fit ring and the length of the press-fit column is used to obtain the force F corresponding to the second force signal when the distance corresponding to the displacement signal is L, and to calculate the bushing stiffness data K, K = F / L; Compare the bushing stiffness data with a preset range. If the bushing stiffness data is outside the preset range, mark the frame bushing as a defective part. If the bushing stiffness data is within the preset range, mark the frame bushing as a qualified part, and the test is completed. Continue operating the pressing component to press down on the qualified component. The qualified component is pressed down and squeezes the positioning end away from each other until the qualified component is pressed to the target depth of the frame sleeve, thus completing the assembly.

10. The method for inspecting and assembling the frame bushing as described in claim 9, characterized in that: The thrust applied to the positioning end is less than the downward force applied to the pressing component, so that when the downward pressing distance of the pressing component is greater than L, the pressing component presses down on the qualified part and squeezes the positioning end to separate from each other until the qualified part enters the frame sleeve.

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