A glue-riveting connection control system and control method

Abstract

The application relates to the technical field of metal material connection, in particular to a glue-riveting connection control system and a control method, which are used for connecting a plate mechanism, the plate mechanism comprises a first plate, a glue liquid layer and a second plate arranged along the thickness direction of the plate mechanism, the glue-riveting connection control system comprises a punch mechanism, a positioning die, a pressure ring mechanism, a fluid guiding structure and a control mechanism, the symmetrical fluid guiding structures are arranged on the opposite surfaces of the pressure ring body and the positioning die, the fluid guiding structures are communicated with the external environment, in the glue-riveting process, the high-pressure area generated by the glue liquid layer under pressure forms a pressure difference with the external environment, so that the glue liquid in the glue liquid layer can generate directional flow along the fluid guiding structure, the hydrostatic pressure generated by the glue liquid layer is reduced, the geometric precision and the connection quality of the formed connecting piece after glue-riveting connection are improved, meanwhile, the uniform glue liquid layer thickness is reserved while the glue liquid discharge efficiency is ensured, and the bonding strength of the glue-riveting connection process is improved.

Description

Technical Field

[0001] This application relates to the field of metal material joining technology, and in particular to a glue riveting joint control system and control method. Background Technology

[0002] In recent years, adhesive-riveting hybrid connection technology has been widely used in fields such as automotive, aerospace, and rail transportation, which have stringent requirements for lightweight, high-strength, and high-reliability structures, especially in the connection of dissimilar materials such as aluminum alloys, high-strength steel, and composite materials. This technology combines the reliability of mechanical connections (such as self-piercing riveting and zip riveting) with the high strength and sealing properties of adhesive bonding, representing an important development direction for lightweight structural connections.

[0003] In the existing adhesive riveting hybrid connection process, there is still a prominent technical problem: when the riveting punch presses down at high speed and penetrates the upper plate to form the rivet head to achieve mechanical interlocking, the structural adhesive pre-coated between the two plates has high viscosity and near-incompressible fluid properties, and cannot be discharged or flow in time in the closed cavity, thus generating huge hydrostatic pressure in the local area. This transient high pressure can reach hundreds of megapascals, far exceeding the design tolerance of conventional adhesives, causing a series of negative problems: (1) The huge hydrostatic pressure will cause the board to bulge, warp or even local buckling deformation, resulting in low dimensional accuracy and poor assembly quality of the board; (2) High pressure may force the adhesive layer to produce voids, debonding or uneven extrusion of adhesive at key interfaces, resulting in less effective bonding area and reduced interfacial bonding strength, weakening the contribution of adhesive to the overall connection performance; (3) In application scenarios involving electrical connection or electromagnetic shielding requirements (such as the battery pack shell of new energy vehicles), uneven distribution or local absence of adhesive layer will significantly degrade the conductivity continuity of the connection area, affecting the electrical performance and safety of the whole vehicle or system. Summary of the Invention

[0004] This application aims to at least solve one of the aforementioned technical problems existing in the prior art. Therefore, the purpose of this application is to provide a glue-riveting connection control system and method, which can solve the problem that bulging deformation easily occurs in existing glue-riveting hybrid connection processes, resulting in low dimensional accuracy of the sheet metal and poor connection quality.

[0005] To achieve the above objectives, the technical solution adopted in this application is as follows:

[0006] A glued riveting connection control system is used to connect a sheet metal mechanism, the sheet metal mechanism including a first sheet metal, an adhesive layer, and a second sheet metal disposed along its thickness direction, the glued riveting connection control system comprising:

[0007] A punch mechanism includes a punch body and a first sensor disposed on the punch body, wherein the first sensor is used to detect the pressure exerted by the punch body on the first plate.

[0008] A positioning mold is used to support and position the sheet metal mechanism;

[0009] The pressure ring mechanism is located between the punch body and the positioning mold. The pressure ring mechanism includes a pressure ring body and a second sensor disposed thereon. The second sensor is used to detect the hydrostatic pressure generated by the adhesive layer during the adhesive riveting process.

[0010] A fluid guiding structure, which is connected to the external environment, is disposed on the opposing surfaces of the pressure ring body and the positioning mold. The fluid guiding structure is used to guide the adhesive in the adhesive layer to flow in a directional manner to the external environment in order to reduce the hydrostatic pressure.

[0011] A control mechanism, which is connected to the first sensor and the second sensor.

[0012] According to some embodiments of this application, the fluid guiding structure is symmetrically disposed on the opposing surfaces of the pressure ring body and the positioning mold. The fluid guiding structure includes a plurality of first flow channels and a plurality of second flow channels. The first flow channels are disposed circumferentially and evenly at intervals around the central axis of the pressure ring body and the central axis of the positioning mold on the opposing surfaces of the pressure ring body and the positioning mold, respectively. The end of the first flow channel away from the center of the pressure ring body is connected to the external environment. The second flow channels are disposed at an angle to the first flow channels.

[0013] According to some embodiments of this application, the included angle ranges from 30° to 60°, so as to reduce the local resistance of the adhesive at the connection between the first flow channel and the second flow channel.

[0014] According to some embodiments of this application, the width of the second flow channel is 0.5 to 0.8 times the width of the first flow channel, and the width of the first flow channel ranges from 0.5 mm to 1.5 mm.

[0015] According to some embodiments of this application, the depths of the first flow channel and the second flow channel are the same and both are less than the thickness of the pre-formed adhesive layer, and the depth ranges from 20μm to 150μm.

[0016] According to some embodiments of this application, a plurality of second sensors are provided, and they are evenly distributed circumferentially around the central axis of the pressure ring body on the surface of the pressure ring body near the first plate. The second sensors are used to detect the pressure balance state of the circumferential region of the first plate.

[0017] According to some embodiments of this application, the adhesive riveting connection control system further includes a viscosity detection mechanism connected to the control mechanism for detecting the viscosity of the adhesive liquid.

[0018] A method for controlling adhesive riveting connections, implemented using the aforementioned adhesive riveting connection control system, includes:

[0019] When the adhesive riveting process begins, the control mechanism detects the dynamic viscosity of the adhesive and matches the pressure applied to the first plate by the punch body according to the dynamic viscosity.

[0020] After the punch body presses down and contacts the first plate, the second sensor detects the hydrostatic pressure inside the adhesive layer in real time. When the hydrostatic pressure value exceeds the preset threshold, the pressure applied by the punch body to the first plate is increased, so that the adhesive flows to the external environment along the fluid guide structure until the hydrostatic pressure value drops back to below the preset threshold. The bonding stage ends and the riveting forming stage begins.

[0021] During the riveting stage, the control mechanism adjusts the pressure exerted by the punch body on the first plate by the pressure value detected by the first sensor, ensuring that the rivet penetrates the first plate and that a mechanical interlocking structure is formed between the first plate and the second plate.

[0022] When the punch body continues to press down until the first sensor detects the maximum pressure, it proves that the mechanical interlock has been completed, the riveting and forming stage has ended, and the glue riveting connection process has been completed.

[0023] According to some embodiments of this application, a mechanical interlocking structure is formed between the first plate and the second plate, including: a rivet for riveting, the bottom of which enters the interior of the second plate and extends circumferentially to produce a transverse upsetting deformation, and the bottom cross-sectional area of ​​the rivet increases, so that the rivet forms a mechanical interlocking structure between the first plate and the second plate.

[0024] According to some embodiments of this application, the fluid guiding structure includes a plurality of first flow channels and a plurality of second flow channels. Both the first flow channels and the second flow channels are formed by etching with a laser. The average processing power of the laser is 10W to 40W, and the pulse frequency is 100kHz to 1000kHz. The first flow channels are processed with a first power parameter, which is more than 80% of the average processing power. The second flow channels are processed with a second power parameter, which is 30% to 50% of the average processing power.

[0025] The beneficial effects of this application are:

[0026] This application sets symmetrical fluid guiding structures on the opposing surfaces of the pressure ring body and the positioning mold. The fluid guiding structures are connected to the external environment. During the adhesive riveting process, the high-pressure area generated by the adhesive layer due to pressure forms a pressure difference with the external environment, thereby causing the adhesive in the adhesive layer to flow in a directional manner along the fluid guiding structure. This reduces the hydrostatic pressure generated by the adhesive layer, improves the geometric accuracy and connection quality of the formed connector after adhesive riveting, and at the same time, while ensuring the efficiency of adhesive discharge, it maintains a uniform adhesive layer thickness, thereby improving the bonding strength of the adhesive riveting hybrid connection process.

[0027] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0028] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0029] Figure 1 This is a schematic diagram of the adhesive riveting control system of this application.

[0030] Figure 2 This is a top view of the fluid guiding structure located on the pressure ring body.

[0031] Figure 3 This is a side view of the fluid guiding structure located on the pressure ring body.

[0032] Figure 4 This is a schematic diagram of a viscosity testing mechanism.

[0033] Figure 5 This is a flowchart of the adhesive riveting connection control method.

[0034] Figure label:

[0035] 100. Punch body; 200. First sensor; 300. Pressure ring body; 310. Punch channel; 400. Second sensor; 500. Sheet metal structure; 510. First sheet metal; 520. Adhesive layer; 530. Second sheet metal; 600. Fluid guiding structure; 610. First flow channel; 620. Second flow channel; 630. Inter-channel plane; 700. Positioning mold; 800. Viscosity detection mechanism; 900. Glue injection device. Detailed Implementation

[0036] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0037] In the description of this application, it should be understood that if directional descriptions are involved, such as up, down, front, back, left, right, etc., indicating the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings, it is only for the convenience of describing this application and simplifying the description, and does 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, and therefore should not be construed as a limitation of this application.

[0038] In the description of this application, if words such as several, greater than, less than, exceeding, above, below, or within appear, "several" means one or more, "more than" means two or more, "greater than," "less than," "exceeding," etc. are understood to exclude the number itself, and "above," "below," "within," etc. are understood to include the number itself.

[0039] In the description of this application, the use of terms such as "first" and "second" is for the purpose of distinguishing technical features only, and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the order of the technical features indicated.

[0040] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0041] Reference Figures 1 to 5 The following are specific embodiments of this application.

[0042] Depend on Figure 1 As shown, this application provides a riveting connection control system for connecting sheet metal mechanisms 500. The sheet metal mechanism 500 includes a first sheet metal 510, an adhesive layer 520, and a second sheet metal 530 arranged along its thickness direction. The riveting connection control system includes a punch mechanism, a positioning mold 700, a pressure ring mechanism, a fluid guiding structure 600, and a control mechanism (not shown). The punch mechanism includes a punch body 100 and a first sensor 200 disposed on the punch body 100. The punch body 100 is used to apply pressure to the first sheet metal 510 to achieve riveting between the first sheet metal 510 and the second sheet metal 530. The first sensor 200 is used to detect the pressure exerted by the punch body 100 on the first sheet metal 510 in real time. The positioning mold 700 is used to support and position the sheet metal mechanism 500. The pressure ring mechanism is located between the punch body 100 and the positioning mold 700. The pressure ring mechanism includes a pressure ring body 300 and a second sensor 400 disposed thereon. The second sensor 400 is used to detect the hydrostatic pressure generated in the adhesive layer 520 during the riveting process. The punch body 100 and the pressure ring body 300 share the same central axis, ensuring that uniform pressure is applied to the sheet metal during the adhesive riveting process.

[0043] The control mechanism is connected to the first sensor 200 and the second sensor 400. The control mechanism is a PLC controller or a numerical control system.

[0044] Furthermore, a power mechanism (not shown) is provided, which is one of a servo motor, a hydraulic system, or a linear motor, to provide power to the punch body 100 and the pressure ring body 300 to provide the driving force required for riveting and pressing.

[0045] The fluid guiding structure 600 is connected to the external environment and is symmetrically arranged on the opposing surfaces of the pressure ring body 300 and the positioning mold 700. The fluid guiding structure 600 is used to guide the adhesive in the adhesive layer 520 to flow directionally to the external environment. Specifically, it creates a pressure difference in the closed adhesive riveting environment, guiding the adhesive to flow directionally, thereby reducing the hydrostatic pressure of the adhesive layer 520. The power mechanism is connected to the punch body 100 and the pressure ring body 300, and the control mechanism is connected to the power mechanism, the first sensor 200, and the second sensor 400.

[0046] Symmetrical fluid guiding structures 600 are provided on the opposing surfaces of the pressure ring body 300 and the positioning mold 700. The patterns, shapes and relative positions of the fluid guiding structures 600 on the two surfaces are completely consistent in the vertical direction (i.e. along the thickness direction of the first plate 510), thus establishing a symmetrical flow field, eliminating lateral shear force gradients, preventing asymmetric plastic warping of the plate, and doubling the pressure relief efficiency through the "double-sided channel effect".

[0047] Specifically, if only one side is provided, for example, the positioning mold 700 has a fluid guiding structure 600, the lower interface between the second plate 530 and the positioning mold 700 has a low-resistance glue discharge channel, while the upper interface between the first plate 510 and the pressure ring body 300 maintains high flow resistance. This asymmetry will cause the center point of the hydrostatic pressure inside the glue layer 520 to shift, thus generating an unbalanced pressure gradient along the vertical direction. By setting both sides to achieve geometric congruence and projection coincidence, it can be ensured that the pressure distribution curves at the upper and lower interfaces are completely symmetrical, so that the resultant force perpendicular to the plate surface points to the center, eliminating the offset force. The glue is discharged outward at the same rate at the upper and lower interfaces. According to the principle of mechanical equilibrium, the outward shear force on the first plate 510 and the outward shear force on the second plate 530 are equal in value and consistent in direction with respect to their respective interfaces, avoiding the tendency of relative slippage between the first plate 510 and the second plate 530, thereby eliminating the lateral shear force gradient.

[0048] Meanwhile, the symmetrical flow field ensures that the first plate 510 and the second plate 530 are subjected to completely synchronized forces in the thickness direction. The balanced load distribution ensures that the first plate 510 and the second plate 530 only undergo compression and plastic deformation required for riveting along their own thickness direction, effectively preventing asymmetric plastic warping of the first plate 510 and the second plate 530 and ensuring the geometric flatness after connection.

[0049] By setting a fluid guiding structure 600 on the pressure ring body 300 and the positioning mold 700, the hydrostatic pressure of the adhesive layer 520 can be released, which solves the problem of bulging deformation of the first plate 510 and the second plate 530 during high-pressure riveting. This improves the geometric accuracy and connection quality of the formed connector after adhesive riveting. At the same time, while ensuring the efficiency of adhesive discharge, it maintains a uniform thickness of the adhesive layer 520, which improves the bonding strength of the adhesive riveting hybrid connection process.

[0050] The adhesive layer 520 is formed by the adhesive injection device 900 through a pipeline (not shown) between the first and second plates.

[0051] Depend on Figure 2 and Figure 3 As shown, in some embodiments, the fluid guiding structure 600 in this application is a leaf vein-like fractal structure, designed based on Murray's Law in fluid mechanics. Compared with Koch curves or mesh-like vascular networks, its advantages are: (1) Optimization of resistance gradient: The multi-level branching of the leaf vein structure ensures that the flow resistance decreases uniformly as the adhesive flows from the central high-pressure zone to the edge, matching the shear-thinning characteristics of non-Newtonian fluids (structural adhesives). (2) Instantaneous pressure drop efficiency: The fractal open-circuit system avoids the "flow dead zone" and air encapsulation of the vascular network structure, ensuring that the hydrostatic pressure is released instantaneously within the riveting pulse time (millisecond level). (3) Minimization of path energy consumption: The radial main channel provides the shortest pressure discharge path, effectively reducing the resistance loss along the path.

[0052] The fluid guiding structure 600 includes a plurality of first flow channels 610 and a plurality of second flow channels 620. The first flow channels 610 are evenly spaced circumferentially around the central axis of the pressure ring body 300 and the central axis of the positioning mold 700 on the opposing surfaces of the pressure ring body 300 and the positioning mold 700, respectively. Figure 2 As shown, the pressure ring body 300 and the positioning mold 700 are coaxially arranged. The pressure ring body 300 has a punch channel 310, and the punch body 100 can pass through the punch channel 310 to apply riveting force to the sheet metal mechanism 500. The central axis of the pressure ring body 300, the central axis of the positioning mold 700 and the central axis of the punch channel 310 coincide.

[0053] The end of the first flow channel 610 furthest from the center of the pressure ring body 300 is connected to the external environment. The second flow channel 620 is set at an angle around the first flow channel 610, with the angle ranging from 30° to 60°. This range minimizes the local resistance coefficient of the adhesive at the junction of the first and second flow channels 610 and prevents pressure reduction delay caused by energy loss. Furthermore, the areas on the pressure ring body 300 and the positioning mold 700 other than the first and second flow channels 610 and 620 form an inter-channel plane 630. The inter-channel plane 630 serves as an adhesive layer retention structure. Under the high pressure of the riveting process, its flow resistance is higher than that of the first and second flow channels 610 and 620, which effectively suppresses adhesive loss and thus retains the predetermined thickness of the final adhesive layer 520.

[0054] Specifically, during the process of the punch body 100 applying pressure downwards to the first plate 510, the fluid does not pass through the fluid guiding structure 600 on the pressure ring body 300. Instead, the applied adhesive force is transmitted to the fluid guiding structure 600 on the positioning mold 700 through the plate mechanism 500. The interior of the adhesive layer is a sealed environment, and the adhesive is an incompressible liquid. Therefore, a hydrostatic high pressure is generated inside the adhesive layer 520. This high pressure is connected to the external environment through the first flow channel 610, thus creating a low-pressure area. This low-pressure area forms a pressure difference with the high-pressure area, causing the adhesive in the high-pressure area to be actively guided. The adhesive flows outwards into the low-stress region along the first flow channel 610 and the second flow channel 620, accelerating the discharge of excess adhesive and reducing the hydraulic resistance of the adhesive layer 520. At the same time, the first flow channel 610 and the second flow channel 620 on the pressure ring body 300 form a symmetrical flow field with the first flow channel 610 and the second flow channel 620 on the positioning mold 700, ensuring that the first plate 510 and the second plate 530 are subjected to completely synchronized forces in the thickness direction, providing a basis for the subsequent plastic deformation of the first plate 510 and the second plate 530 and rivet penetration.

[0055] Furthermore, the main reason for the pressure difference and directional flow generated in the adhesive layer 520 is that during the process of the punch body 100 applying pressure downward to the first plate 510, the depressions and protrusions of the first flow channel 610 and the second flow channel 620 cause uneven force on the first plate 510, resulting in a local pressure gradient inside the adhesive layer 520. This causes the adhesive to flow laterally from the protrusions to the depressions. At the same time, both the first flow channel 610 and the second flow channel 620 are connected to the outside, which can establish a long-distance pressure difference from the center to the edge of the adhesive layer 520. This causes the adhesive to flow directionally along a low-resistance fractal path. Finally, through this combined effect of "lateral convergence followed by directional discharge", the hydrostatic pressure that would have acted on the plate and caused bulging is successfully offset and converted into kinetic energy for directional flow.

[0056] Meanwhile, during the glued connection, the punch body 100 squeezes the glue to generate a large hydrostatic pressure. Since the structure of the first flow channel 610 and the second flow channel 620 is a low-pressure area relative to the hydrostatic pressure generated by squeezing the glue, the glue will flow directionally from the high-pressure area to the low-pressure area. The first flow channel 610 and the second flow channel 620 are located outside the glue, which will also guide the glue to flow outward in a directional manner.

[0057] Furthermore, since the adhesive only needs to move to the nearest flow channel, that is, to the first flow channel 610 on the pressure ring body 300 or the first flow channel 610 on the positioning mold 700, its average overflow path is shortened. This "double-sided channel effect" not only increases the discharge flow area, but also doubles the pressure relief efficiency by shortening the effective length, thereby rapidly reducing the hydrostatic pressure in milliseconds and solving the problems of bulging and deformation.

[0058] In some embodiments, the depths of the first flow channel 610 and the second flow channel 620 need to be less than the preset final adhesive layer thickness, which can be calculated and optimized based on the adhesive viscosity and the expected adhesive flow rate. Specifically, referring to Poiseuille's law, the calculation formula is as follows:

[0059] ;

[0060] In the formula: Q is the expected flow rate of the adhesive; P represents the pressure difference between the hydrostatic pressure within the adhesive layer and the external ambient pressure; w represents the width of the first flow channel 610; h represents the depth of the first flow channel 610; η represents the dynamic viscosity of the adhesive in the adhesive layer; and L represents the length of the adhesive flow in the fluid guiding structure 600. Since the reference formula is empirical, it needs to be multiplied by a proportionality coefficient k in actual calculations. The value of k is related to the dimensions of the fluid guiding structure 600. If a rectangular flow channel with depth H and width W is used, the value of k depends on the aspect ratio (H / W). Typically, when H is much smaller than W, k is taken as 1 / 12.

[0061] In some embodiments, the width of the first flow channel 610 ranges from 0.5 mm to 1.5 mm, preferably 0.8 mm. The first flow channel 610, as the main channel for adhesive flow, can withstand the maximum instantaneous volumetric discharge in the central region of the adhesive layer 520. The width of the second flow channel 620 is 0.5 to 0.8 times the width of the first flow channel 610, which can maintain the shear stress of the adhesive away from the central region of the adhesive layer 520, ensuring that the adhesive discharge power does not decrease.

[0062] Furthermore, the depths of the first flow channel 610 and the second flow channel 620 are equal and both less than the thickness of the pre-set final adhesive layer, in order to prevent excessive adhesive discharge from causing voids in the adhesive layer 520, while also meeting the requirement for minimum flow area in fluid dynamics.

[0063] The depth ranges from 20μm to 150μm, with 50μm being the preferred value.

[0064] In some embodiments, a plurality of second sensors 400 are provided and evenly distributed on the surface of the pressure ring body 300 near the first plate 510. The second sensors 400 are used to detect the hydrostatic pressure generated in the adhesive layer 520.

[0065] Specifically, the second sensor 400 is an embedded piezoelectric sensor. Four of them are evenly distributed around the central axis of the pressing ring body 300 in the circumferential direction. The included angle between adjacent embedded piezoelectric sensors is 90 degrees. It is used to detect the pressure balance state of the circumferential area of ​​the first plate 510 and to provide real-time feedback on the hydrostatic pressure generated by the obstruction of the adhesive during the riveting and extrusion process.

[0066] Depend on Figure 4 As shown, in some embodiments, the adhesive riveting control system further includes a viscosity detection mechanism 800, which is connected to the control mechanism and is used to detect the viscosity of the adhesive in the adhesive layer 520.

[0067] Specifically, the viscosity detection mechanism 800 is a viscosity sensor, which is connected to the dispensing device 900. The viscosity sensor is used to detect the dynamic viscosity of the adhesive injected by the dispensing device 900. The dispensing device 900 is a glue gun or a dispensing machine.

[0068] Since the viscosity of the adhesive varies with ambient temperature or batch, the viscosity detection mechanism 800 can provide the viscosity value of the adhesive to the control mechanism in real time, thereby matching the optimal rheological compensation factor in the characteristic curve pre-stored in the control mechanism, and then dynamically calculating the pressure required for the riveting process.

[0069] Depend on Figure 5 As shown, this application also provides a method for controlling adhesive riveting connections, implemented using an adhesive riveting connection control system, comprising:

[0070] S100, the adhesive riveting process begins. The control mechanism detects the dynamic viscosity of the adhesive and matches the pressure applied by the punch body 100 to the first plate 510 according to the dynamic viscosity.

[0071] Specifically, the glue injection device 900 injects glue into the gap between the first plate 510 and the second plate 530 to form a glue layer 520. Then, the viscosity detection mechanism 800 detects the dynamic viscosity of the glue and transmits it to the control mechanism. The control mechanism calculates the pressure required for the riveting process based on the dynamic viscosity and applies the required pressure to the punch body 100 through the power mechanism. The punch body 100 then begins to press down.

[0072] S200. After the punch body 100 presses down to contact the first plate 510, the second sensor 400 detects the hydrostatic pressure inside the adhesive layer 520 in real time. When the hydrostatic pressure value exceeds the preset threshold, the pressure applied by the punch body to the first plate is increased, so that the adhesive flows to the external environment along the fluid guiding structure 600 until the hydrostatic pressure value drops back to below the preset threshold. The bonding stage ends and the riveting forming stage begins.

[0073] Specifically: The punch body 100 begins to press down along the thickness direction of the plate structure 500 and contact the first plate 510. At this time, the second sensor 400 detects the hydrostatic pressure generated inside the adhesive layer 520 in real time and transmits it to the control mechanism for comparison with a preset threshold. If the hydrostatic pressure value is greater than the preset threshold, the control mechanism controls the power mechanism to increase the pressure applied by the punch body 100 to the first plate 510, so that the adhesive can flow directionally along the first flow channel 610 and the second flow channel 620 to the external environment to discharge excess adhesive, until the hydrostatic pressure value is less than the preset threshold, preventing bulging deformation between the first plate 510 and the second plate 530. At the same time, it indicates that the adhesive distribution tends to be stable, and a uniform adhesive layer thickness is maintained on the inter-channel plane 630. The bonding stage ends and the riveting forming stage begins.

[0074] S300. During the riveting stage, the control mechanism adjusts the pressure of the punch body 100 on the first plate 510 based on the value detected by the first sensor 200, so as to ensure that the rivet penetrates the first plate 510 and forms a mechanical interlocking structure with the second plate 530.

[0075] Specifically, the first sensor 200 detects the pressure exerted by the punch body 100 on the first plate 510 and transmits it to the control mechanism. The control mechanism adjusts the final pressure applied by the punch body 100 on the first plate 510, i.e. the final riveting force. The value of the final riveting force can ensure that the rivet penetrates the first plate 510 and the bottom of the rivet enters the second plate 530. The end of the rivet enters the interior of the second plate 530 and expands circumferentially, producing a transverse upsetting deformation. The cross-sectional area of ​​the bottom of the rivet increases, forming an anchor head in the second plate 530, so that the rivet forms a stable mechanical interlocking structure between the first plate 510 and the second plate 530.

[0076] The mechanical interlocking structure ensures localized metal-to-metal direct contact between the first and second plates, preventing the adhesive film from blocking the conductive path and improving the electrical performance of the connected parts.

[0077] S400. When the punch body 100 continues to press down until the first sensor 200 detects the maximum pressure, it proves that the mechanical locking has been completed, the riveting and forming stage has ended, and the glue riveting connection process has been completed.

[0078] Specifically, when the first sensor 200 detects the maximum pressure, it indicates that the rivet has been fully formed and the mechanical interlocking structure has been established. At this time, the thickness of the adhesive layer 520 is uniform, and the entire adhesive riveting connection process is completed.

[0079] Furthermore, the rivets used in the riveting process are located at the front end of the punch body 100, directly facing the surface of the first plate 510, and can be pressed down together with the punch body 100 to complete penetration and forming.

[0080] In some embodiments, the first flow channel 610 and the second flow channel 620 are both formed by etching using a laser (not shown). The laser is a picosecond laser or a femtosecond ultrafast laser. The surface of Cr12MoV mold steel or H13 mold steel is prepared by "cold working" flow channel structure to form the first flow channel 610 and the second flow channel 620 without heat-affected zone.

[0081] In some embodiments, the laser has an average processing power of 10W to 40W and a pulse frequency of 100kHz to 1000kHz. The first flow channel 610 is processed using a first power parameter, which is more than 80% of the average processing power, and is processed using a multi-scan strategy to achieve a depth of 100μm to 150μm. The second flow channel 620 is processed using a second power parameter, which is 30% to 50% of the average processing power.

[0082] The adhesive riveting connection control process of this application uses a second sensor to detect the hydrostatic pressure generated in the adhesive layer in real time. The control mechanism dynamically adjusts the riveting force of the punch body on the first plate based on the hydrostatic pressure value. When the detected hydrostatic pressure value exceeds a preset threshold, the control mechanism increases the riveting force of the punch body until the adhesive flows into the external environment along the first and second flow channels. This releases the high hydrostatic pressure and converts the harmful hydrostatic pressure into controlled directional flow of the adhesive, thus preventing bulging and deformation between the first and second plates.

[0083] In some embodiments, S100, the riveting force is calculated based on the Stephen equation, according to the pressure applied to the first plate 510 by the dynamic viscosity matching punch body 100. The calculation formula is as follows:

[0084] ;

[0085] In the formula: F is the riveting force applied by the punch body 100; η is the dynamic viscosity of the adhesive in the adhesive layer; R is the effective clamping radius of the positioning mold 700 or the pressure ring body 300; h1 is the thickness of the real-time adhesive layer 520; t is the descent time of the punch body 100 to obtain the current thickness of the adhesive layer 520, i.e., the pressing rate of the punch body 100; dh1 / dt is the pressing rate of the punch body 100; K is a correction coefficient. This is a compensation factor.

[0086] Preferably, K is 1 / 16. When the value equals 0, that is, no fluid guiding structure 600 is set, when A value greater than 0.9 indicates that the adhesive layer 520 is discharged too quickly, failing to guarantee adhesive quality. The value range is 0.4 to 0.7.

[0087] The range of riveting force values ​​set according to dynamic viscosity is shown in Table 1:

[0088] Table 1. Riveting Force Range

[0089]

[0090] As shown in Table 1, by dynamically matching the riveting force with different value ranges based on dynamic viscosity, the pressure applied to the adhesive layer 520 can be more accurately controlled compared to using a constant reference force. This can suppress the increase of hydrostatic pressure inside the adhesive layer 520 and eliminate the bulging phenomenon between the first plate 510 and the second plate 530.

[0091] The control mechanism has a pre-stored pressure-flow rate characteristic curve, which means that the control mechanism can determine different riveting forces and generate hydrostatic pressure at a specified dynamic viscosity of the adhesive, thereby controlling the riveting force applied by the punch body 100 during the entire adhesive riveting process, ensuring that the adhesive can be discharged through the fractal flow channel in a timely manner.

[0092] Example 1

[0093] In this embodiment, both the first plate 510 and the second plate 530 are made of aluminum alloy with a thickness of 2 mm. The adhesive is a structural adhesive with a dynamic viscosity of 250 Pa·s. By etching a first flow channel 610 and a second flow channel 620 with a depth of 50 μm on the surfaces of the pressure ring body 300 and the positioning mold 700, respectively, the riveting force of the punch body 100 is increased from the traditional 50 kN to 65 kN to 70 kN. Experiments have shown that this pressure gradient, combined with the first flow channel 610 and the second flow channel 620, can reduce the hydrostatic pressure in the central region of the adhesive layer 520 by more than 60% within 200 ms, completely eliminating the bulging phenomenon between the first plate 510 and the second plate 530.

[0094] This application discloses a glue riveting control system and method. By setting a first flow channel and a second flow channel connected to the external environment on the pressure ring body and the positioning mold, the glue can be discharged to the external environment, releasing the hydrostatic pressure generated by the glue layer due to glue obstruction. This solves the problem of bulging deformation of the sheet metal under high-pressure riveting, ensuring the geometric accuracy and connection quality of the connector. While ensuring the glue flow efficiency, a stable and uniform glue layer thickness is maintained on the plane between the channels, improving the bonding strength of the glue riveting connection. A first sensor is set on the punch body, and a second sensor is set on the pressure ring body. The entire glue riveting process is controlled by a control mechanism. The control mechanism can control the riveting force of the punch body according to the dynamic viscosity of the glue, realizing active and closed-loop control of the glue flow and mechanical riveting forming process, ensuring the stability of the glue riveting connection. Finally, compared with the expensive and complex existing technologies such as electromagnetic pulse control, this application requires no external energy compensation and has significant advantages such as zero-delay response, no electromagnetic interference, extremely simple system, and low maintenance cost.

[0095] In the description of this specification, the use of terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," and "some examples" indicates that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0096] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A glued riveting connection control system, characterized in that, A plate-connecting mechanism, the plate-connecting mechanism comprising a first plate, an adhesive layer, and a second plate disposed along its thickness direction, the adhesive riveting connection control system comprising: A punch mechanism includes a punch body and a first sensor disposed on the punch body, wherein the first sensor is used to detect the pressure exerted by the punch body on the first plate. A positioning mold is used to support and position the sheet metal mechanism; The pressure ring mechanism is located between the punch body and the positioning mold. The pressure ring mechanism includes a pressure ring body and a second sensor disposed thereon. The second sensor is used to detect the hydrostatic pressure generated by the adhesive layer during the adhesive riveting process. A fluid guiding structure, which is connected to the external environment, is disposed on the opposing surfaces of the pressure ring body and the positioning mold. The fluid guiding structure is used to guide the adhesive in the adhesive layer to flow in a directional manner to the external environment in order to reduce the hydrostatic pressure. The fluid guiding structure is symmetrically disposed on the opposing surfaces of the pressure ring body and the positioning mold. The fluid guiding structure includes a plurality of first flow channels and a plurality of second flow channels. The first flow channels are disposed circumferentially and evenly at intervals around the central axis of the pressure ring body and the central axis of the positioning mold on the opposing surfaces of the pressure ring body and the positioning mold, respectively. The end of the first flow channel away from the center of the pressure ring body is connected to the external environment. The second flow channels are set at an angle to the first flow channels, with the angle ranging from 30° to 60°, in order to reduce the local resistance of the adhesive at the connection between the first flow channels and the second flow channels. The width of the second flow channel is 0.5 to 0.8 times the width of the first flow channel, and the width of the first flow channel ranges from 0.5 mm to 1.5 mm. A control mechanism, which is connected to the first sensor and the second sensor.

2. The adhesive riveting connection control system according to claim 1, characterized in that, The first flow channel and the second flow channel have the same depth and are both less than the thickness of the pre-formed adhesive layer. The depth ranges from 20μm to 150μm.

3. The adhesive riveting connection control system according to claim 1, characterized in that, The second sensor is provided in multiple units and is evenly distributed circumferentially around the central axis of the pressure ring body on the surface of the pressure ring body near the first plate. The second sensor is used to detect the pressure balance state of the circumferential area of ​​the first plate.

4. The adhesive riveting connection control system according to claim 1, characterized in that, The adhesive riveting control system also includes a viscosity detection mechanism, which is connected to the control mechanism and is used to detect the viscosity of the adhesive liquid.

5. A method for controlling adhesive riveting connections, characterized in that, The adhesive riveting connection control system according to any one of claims 1-4 is used, comprising: When the adhesive riveting process begins, the control mechanism detects the dynamic viscosity of the adhesive and matches the pressure applied to the first plate by the punch body according to the dynamic viscosity. After the punch body presses down and contacts the first plate, the second sensor detects the hydrostatic pressure inside the adhesive layer in real time. When the hydrostatic pressure value exceeds the preset threshold, the pressure applied by the punch body to the first plate is increased, so that the adhesive flows to the external environment along the fluid guide structure until the hydrostatic pressure value drops back to below the preset threshold. The bonding stage ends and the riveting forming stage begins. During the riveting stage, the control mechanism adjusts the pressure exerted by the punch body on the first plate by the pressure value detected by the first sensor, ensuring that the rivet penetrates the first plate and that a mechanical interlocking structure is formed between the first plate and the second plate. When the punch body continues to press down until the first sensor detects the maximum pressure, it proves that the mechanical interlock has been completed, the riveting and forming stage has ended, and the glue riveting connection process has been completed.

6. The adhesive riveting connection control method according to claim 5, characterized in that, The first plate and the second plate form a mechanical interlocking structure, including: a rivet for riveting whose bottom enters the interior of the second plate and expands circumferentially, producing a transverse uplift deformation, and the bottom cross-sectional area of ​​the rivet increases, so that the rivet forms a mechanical interlocking structure between the first plate and the second plate.

7. The adhesive riveting connection control method according to claim 5, characterized in that, Both the first flow channel and the second flow channel are formed by etching with a laser. The average processing power of the laser is 10W to 40W and the pulse frequency is 100kHz to 1000kHz. The first flow channel is processed with a first power parameter, which is more than 80% of the average processing power. The second flow channel is processed with a second power parameter, which is 30% to 50% of the average processing power.

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