A vibration head and a vibration friction welding machine using the same

Abstract

The application discloses a vibration head and a vibration friction welding machine applying the same, and relates to the technical field of friction welding machines.The vibration head comprises a displacement driving mechanism and an upper die clamp.The high-frequency low-amplitude vibration between workpieces to be welded is realized through an electromagnetic vibration device, sufficient friction heat can be quickly generated without infrared heating, and the welding efficiency and quality are effectively improved.Meanwhile, the driving mechanism in the upper die clamp drives the driven jaw mechanism to move asynchronously, the longitudinal distance adjustment and adsorption function of the multi-point abutting mechanism are combined, the clamping angle and position can be adaptively adjusted according to the shape difference of the workpieces to be welded, the reliable fixation of irregular workpieces is ensured, the workpiece deviation caused by insufficient clamping force is avoided, the adaptability of vibration welding to workpieces with different shapes is significantly improved, and the limitation of traditional equipment in the welding of complex workpieces is overcome.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of friction welding machines, in particular to a vibration head and a vibration friction welding machine using the same. BACKGROUND

[0002] Vibration welding is a friction welding process, the workpieces to be welded are rubbed together under pressure until the generated friction and shear heat at the contact surface reaches a fully molten state. When the set welding depth is reached, the relative movement stops, and the welding seam cools and solidifies.

[0003] The vibration frequency of the linear vibration friction welding device is only 100-240 Hz at present, and the amplitude has a greater requirement during welding, otherwise it is difficult to achieve the fusion effect. At the same time, the friction heat energy generated at this vibration frequency cannot fully heat the plastic workpieces to be welded, which directly affects the welding quality. For this, the prior art generally installs an infrared heating device to preheat the plastic workpieces to be welded to ensure that the welding part melts during welding to achieve the desired welding effect.

[0004] Secondly, during the welding process of the plastic workpiece, the workpiece will generate resistance due to friction, and the clamp is required to provide sufficient clamping force to ensure welding precision and stability. For regular-shaped workpieces, the regular shape of the workpiece can provide sufficient clamping area, and the traditional synchronous clamping clamp can meet the welding requirements. However, for complex structure and irregular surface of special-shaped workpieces, it is difficult for the conventional clamp to achieve reliable fixation due to the lack of stable clamping surface, and problems such as insufficient clamping force, workpiece deviation and even falling off are prone to occur.

[0005] Therefore, the present application provides a vibration head and a vibration friction welding machine using the same to solve the above problems. SUMMARY

[0006] In view of the problems existing in the prior art, the present application is proposed.

[0007] To solve the above technical problems, the present application provides the following technical scheme: a vibration head, comprising a displacement driving mechanism and an upper die clamp; the displacement driving mechanism comprises a vibration head frame and two groups of electromagnetic vibration devices symmetrically arranged in the inner cavity of the vibration head frame, the electromagnetic vibration device comprises a plate-shaped spring arranged from the center of the vibration head frame to the end, a driving armature and an electromagnetic coil, the driving armature penetrates through the inner cavity of the vibration head frame and is connected with a vibration plate, and the electromagnetic coil is connected with a vibration source for alternately inputting electric energy to the electromagnetic coil away from the end of the driving armature.

[0008] The upper die clamp comprises a positioning chuck, a driving mechanism arranged in the positioning chuck, a plurality of sets of driven jaw mechanisms arranged circumferentially on the surface of the positioning chuck, and a multi-point abutting mechanism connected to the free end of the driven jaw mechanisms, the multi-point abutting mechanism comprises a longitudinal distance adjusting mechanism and a suction mechanism, the driving mechanism drives the non-synchronous movement of the plurality of sets of driven jaw mechanisms to drive the multi-point abutting mechanism to abut against different clamping surfaces of the workpiece to be welded.

[0009] As a preferred scheme of the vibration head, the positioning chuck comprises a lower disc box, an upper disc cover assembled on the lower disc box, a central mounting cylinder extending downward from the center of the upper disc cover, and a central gear set clamped on the central mounting cylinder; the central gear set comprises not less than three sets of central clamping gears stacked along the axis direction of the lower disc box, and the central clamping gears rotate around the axis of the lower disc box under the action of external force.

[0010] As a preferred scheme of the vibration head, the number of the driving mechanisms is not less than three, and each driving mechanism is used to drive not less than three sets of central clamping gears; the driving mechanisms comprise two sets of driving units arranged symmetrically in the lower disc box, and one set of the driving units is engaged with a driving motor; the driving unit comprises a driving gear engaged with the central clamping gear and a driving main rotating shaft arranged at the center of the driving gear.

[0011] As a preferred scheme of the vibration head, each set of the driven jaw mechanisms comprises two driven jaw units arranged symmetrically in the lower disc box, the driven jaw unit comprises a guide plate assembled on the upper disc cover, a double-toothed rack plate clamped in the guide slot of the guide plate, and a driven gear set for driving the double-toothed rack plate to move in the guide slot of the guide plate, the driven gear set is engaged with the central clamping gear.

[0012] As a preferred scheme of the vibration head, the longitudinal distance adjusting mechanism comprises a supporting circumferential shaft, a basic support body rotatably connected to the supporting circumferential shaft, a rotating arm set arranged in the inner cavity of the basic support body, and an angular rotating mechanism for driving the rotating arm set to rotate in the inner cavity of the basic support body, the suction mechanism comprises a suction structure and a negative pressure pump, the suction structure is arranged on the rotating arm set, and the negative pressure pump is connected to the suction structure through a hose.

[0013] As a preferred scheme of the vibration head, the basic support body comprises a shaft seat clamped on the support circumferential shaft, a base plate cylinder assembled on the shaft seat, a transfer head clamped in the inner cavity of the base plate cylinder, and three clamping jaw connecting plates connected to the transfer head away from the shaft seat end; the base plate cylinder is rotationally connected to the support circumferential shaft through the shaft seat, so that the base plate cylinder pitches along the support circumferential shaft, the negative pressure pump is arranged on the surface of the base plate cylinder, the transfer head is spun along the central axis of the base plate cylinder under external force, and the three clamping jaw connecting plates are distributed at equal intervals along the radial direction of the transfer head, and the central axis of the clamping jaw connecting plate is perpendicular to the direction of the axis of the transfer head.

[0014] As a preferred scheme of the vibration head, the angle rotating mechanism comprises a rotating motor assembled on the base plate cylinder, a rotating gear arranged at the output end of the rotating motor, and a linkage gear coaxially arranged on the surface of the transfer head, and the rotating motor drives the linkage gear and the transfer head to rotate synchronously through the rotating gear.

[0015] As a preferred scheme of the vibration head, the rotating arm group is arranged on each clamping jaw connecting plate, the rotating arm group comprises a first rotating arm fixedly assembled on the clamping jaw connecting plate, a second rotating arm hingedly connected to the first rotating arm, and a gas cylinder structure for driving the angle adjustment between the first rotating arm and the second rotating arm.

[0016] As a preferred scheme of the vibration head, the adsorption structure comprises a base mounting plate assembled on the second rotating arm, a plurality of rotating bases mounted on the base mounting plate, and an adsorption head rotationally connected to the rotating base, and the side away from the adsorption end of the adsorption head is connected with a hose.

[0017] A vibration friction welding machine comprising the vibration head, further comprising a machine tool frame, a three-axis driving structure for connecting the vibration head and the machine tool frame, and a lower die clamp mounted on the machine tool frame.

[0018] The vibration head has the advantages that high-frequency low-amplitude vibration between the workpieces to be welded is realized by the electromagnetic vibration device, sufficient friction heat can be quickly generated without infrared heating, the welding efficiency and quality are effectively improved, the driven clamping jaw mechanism is driven to move asynchronously by the active driving mechanism in the upper die clamp, the longitudinal distance adjustment and adsorption functions of the multi-point abutting mechanism can be combined, the clamping angle and position can be adaptively adjusted according to the shape difference of the workpieces to be welded, the reliable fixation of irregular workpieces is ensured, the workpiece deviation caused by insufficient clamping force is avoided, the adaptability of the vibration welding to workpieces of different shapes is significantly improved, and the limitations of traditional equipment in complex workpiece welding are overcome. BRIEF DESCRIPTION OF DRAWINGS

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of the vibration friction welding machine in this invention;

[0021] Figure 2 This is a front view of the overall structure of the vibration friction welding machine of the present invention;

[0022] Figure 3 This is a structural diagram of the machine tool frame in this invention;

[0023] Figure 4 This is a structural diagram of the displacement driving mechanism in this invention;

[0024] Figure 5 This is a structural diagram of the positioning chuck in this invention;

[0025] Figure 6 For the present invention Figure 5 Enlarged view of the A-section structure;

[0026] Figure 7 This is a schematic diagram of the overall structure of the upper mold fixture in this invention;

[0027] Figure 8 For the present invention Figure 7 Enlarged view of the structure of section B;

[0028] Figure 9 This is a structural diagram of the central gear set in this invention;

[0029] Figure 10 This is a schematic diagram of the overall structure of the multi-point contact mechanism in this invention;

[0030] Figure 11 This is a schematic diagram of the overall structure of the rotating arm assembly in this invention.

[0031] Reference numerals: 110, worktable; 120, support beam; 130, crossbeam; 210, longitudinal drive mechanism; 220, transverse drive mechanism; 230, lifting mechanism; 310, displacement drive mechanism; 3111, headstock box; 3112, side plate; 3113, T-shaped plate; 3121, electromagnetic coil; 3122, drive armature; 3123, plate spring; 3124, vibrating plate; 3131, center guide rail body; 3132, side guide rail body; 3133, damping spring; 320, upper mold fixture; 321, positioning chuck; 3211, upper plate cover; 32111, guide groove; 3212, center mounting cylinder; 3213, lower plate box; 3214, center gear set; 3215, limit plate; 322, active drive mechanism; 3221, drive motor; 3222, drive main rotor Shaft; 3223, Driving gear; 323, Driven chuck mechanism; 3231, Guide plate; 3232, Double-tooth rack plate; 3233, Driven gear; 3234, Driven rotating shaft; 324, Multi-point contact mechanism; 3241, Supporting circumferential shaft; 3242, Basic support body; 32421, Shaft seat; 32422, Base plate cylinder; 32423, Central rotating head; 32424, Chuck receiving plate; 3 243. Angle rotation mechanism; 32431. Rotary motor; 32432. Rotary gear; 32433. Linkage gear; 3244. First rotating arm; 32441. Silicone sensing plate; 3245. Second rotating arm; 3246. Cylinder structure; 3247. Adsorption structure; 32471. Base mounting plate; 32473. Adsorption head; 3248. Negative pressure pump; 330. Lower mold fixture. Detailed Implementation

[0032] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0033] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0034] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0035] Reference Figures 1-11 As shown, this embodiment provides a vibrating head, including a displacement driving mechanism 310 and an upper mold clamping fixture 320:

[0036] The displacement drive mechanism 310 includes a horizontally arranged vibrating head frame, two sets of electromagnetic vibration devices arranged symmetrically in the inner cavity of the vibrating head frame, and a guide device arranged on the bottom surface of the vibrating head frame.

[0037] The vibration head frame includes a head frame box 3111 with a lower opening, side plates 3112 disposed on both sides of the bottom surface of the head frame box 3111, and a T-shaped plate 3113 disposed in the middle of the head frame box 3111. The inner cavity of the head frame box 3111 is divided into left and right chambers that are not connected to each other by the T-shaped plate 3113. Two sets of electromagnetic vibration devices are distributed in the left and right chambers of the head frame box 3111. Two sets of gaps are left between the T-shaped plate 3113 and the side plates 3112.

[0038] The electromagnetic vibration device includes a plate spring 3123, a drive armature 3122, and an electromagnetic coil 3121 arranged from the center of the vibration head frame to the end. The drive armature 3122 is connected to a vibration plate 3124 through a gap. The end of the electromagnetic coil 3121 facing away from the drive armature 3122 is connected to a vibration source for alternately inputting electrical energy into the electromagnetic coil 3121. One end of the plate spring 3123 is connected to a T-shaped plate 3113. The drive armature 3122 is disposed on a side plate 3112. The vibration source is used to alternately input electrical energy into the electromagnetic coil 3121, and the drive armature 3122 and the vibration plate 3124 are driven to vibrate at high frequency and low amplitude through the cooperation of the drive armature 3122 and the plate spring 3123.

[0039] The elastic modulus of the leaf spring 3123 is 150–250 GPa; the vibration frequency range of the drive armature 3122 is 280 Hz–380 Hz, and the amplitude range is configured to be 0.1–1.2 mm.

[0040] The guiding device includes a side guide rail body 3132 mounted on the side plate 3112, a center guide rail body 3131 mounted on the central T-shaped plate 3113, and damping springs 3133 respectively disposed inside the center guide rail body 3131 and the side guide rail body 3132. The center guide rail body 3131 and the side guide rail body 3132 are provided with guide grooves 32111 for the displacement of the vibrating plate 3124, and the damping springs 3133 are disposed in the guide grooves 32111.

[0041] For example, when using an electronic casing to encapsulate precision electronics, the armature 3122 is configured with a vibration frequency of 380Hz and an amplitude of 0.15mm, and the plate spring 3123 is configured with an elastic modulus of 250GPa. Under the conditions of a welding time of 0.8sec and a clamping force of 120N / cm, the electromagnetic coil 3121 inputs an alternating current of 380Hz to drive the armature 3122. Under the constraint of the 250GPa high modulus plate spring 3123, a precision micro-amplitude vibration of ±0.075mm is achieved. The vibration plate 3124 transmits the motion through the guide groove 32111 of the middle guide rail body 3131, driving the upper mold fixture 320 to reciprocate the workpiece bidirectionally at 760 times / second. The damping spring 3133 on the side guide rail body 3132 absorbs the lateral displacement disturbance, so as to achieve a plastic powder generation of less than 3.5mg / time, a weld depth control accuracy of ±0.05mm, and an energy consumption of 0.33kW·h / thousand pieces during the welding of the electronic casing.

[0042] For example, when welding automotive taillights, the drive armature 3122 is configured with a vibration frequency of 300Hz and an amplitude of 0.8mm, and the plate spring 3123 is configured with an elastic modulus of 180GPa. Under the conditions of a welding time of 2.5sec and a clamping force of 350N / cm, the electromagnetic coils 3121 on both sides of the T-shaped plate 3113 are supplied with currents with a 180° phase difference to excite a symmetrical magnetic field. The drive armature 3122 forms an effective stroke of 0.8mm under the energy storage and release of the plate spring 3123 with an elastic modulus of 180GPa. The center guide rail body 3131 suppresses vertical offset, realizing the welding of the lamp cover and the housing with a production cycle of 14 seconds / piece, which is 52% faster than the traditional process and has no melt splashing.

[0043] For example, when welding a medical dialyzer, the drive armature 3122 is configured with a vibration frequency of 365Hz and an amplitude of 0.3mm, the plate spring 3123 is configured with an elastic modulus of 210GPa, and under the conditions of a welding time of 1.2sec and a clamping force of 200N / cm, the vibration source outputs a sinusoidal current with a total harmonic distortion of <2%. The side guide rail body 3132 and the damping spring 3133 work together to suppress lateral vibration, and the guide groove 32111 ensures a trajectory accuracy of ±8μm, achieving a welding that meets clean standards: bacterial adhesion rate <0.02% and PP material weld seam airtightness >0.5MPa.

[0044] During operation, after the electromagnetic coil 3121 is energized, the two sets of electromagnetic vibration devices in the left and right chambers of the head frame box 3111 are input with alternating current from the vibration source. The electromagnetic force in the electromagnetic coil 3121 reaches its peak value in turn. Under the joint action of the plate spring 3123, the armature 3122 is driven to start high-frequency reciprocating motion, which drives the vibrating plate 3124 to reciprocate, realizing the welding function of vibration friction. In this application, the displacement drive mechanism 310 adopts a high-frequency low-amplitude friction method with a vibration frequency range of 280Hz to 380Hz and an amplitude range of 0.1 to 1.2mm. Compared with the traditional friction welding method, it eliminates the need for a preheating device to preheat the plastic workpiece to be welded, making it cheaper and significantly improving work efficiency.

[0045] Secondly, high-frequency vibration friction welding achieves micro-amplitude high-speed friction by driving the armature 3122 with electromagnetic drive. The heat source depth in the molten zone of the workpiece to be welded is reduced compared to traditional processes. This allows the heat source depth in the molten zone of the workpiece to be welded to be strictly controlled within the surface layer of the contact surface. For vibration friction welding machines that require preheating, the entire workpiece or the weld line needs to be heated to above 80°C. This application fundamentally eliminates the problems of dimensional deformation caused by thermal expansion and contraction of the workpiece to be welded, and the changes in welding pressure after preheating of the weld line. Therefore, the tolerance requirements for injection molded parts are lower, the welding process control is simpler, and the welding effect is more stable. In addition, the high-frequency vibration friction welding method of this application achieves micro-amplitude movement by driving the armature 3122 with electromagnetic drive. Its amplitude is only 10%-60% of that of traditional processes, which reduces the space constraints of product design.

[0046] The upper mold fixture 320 includes a positioning chuck 321 disposed on one end of the vibrating plate 3124 away from the drive armature 3122, an active drive mechanism 322 disposed in the positioning chuck 321, multiple sets of driven jaw mechanisms 323 arranged circumferentially on the surface of the positioning chuck 321, and a multi-point abutment mechanism 324 connected to the free end of the driven jaw mechanism 323. The multi-point abutment mechanism 324 includes a longitudinal adjustment mechanism and an adsorption mechanism. The active drive mechanism 322 drives the multiple sets of driven jaw mechanisms 323 to move asynchronously so that the multi-point abutment mechanism 324 abuts against different clamping surfaces of the workpiece to be welded.

[0047] Reference Figure 5 As shown, the positioning chuck 321 includes a lower chuck box 3213, an upper chuck cover 3211 mounted on the lower chuck box 3213, a central mounting cylinder 3212 extending downward from the center of the upper chuck cover 3211, a central gear set 3214 engaged with the central mounting cylinder 3212, and multiple sets of limiting plates 3215 mounted on the inner wall of the lower chuck box 3213; wherein, the upper chuck cover 3211 is provided with multiple guide grooves 32111 circumferentially for arranging the driven claw mechanism 323;

[0048] The central gear set 3214 includes no fewer than three sets of central locking gears stacked along the axis of the lower plate box 3213. The central locking gears rotate around the axis of the lower plate box 3213 when subjected to external force.

[0049] Reference Figure 5 , Figure 6 as well as Figure 9 As shown, the number of active drive mechanisms 322 is not less than three sets, which are used to drive not less than three sets of center locking gears respectively; the active drive mechanism 322 includes two sets of active drive units symmetrically arranged in the lower plate box 3213, and one set of active drive units is engaged with drive motor 3221.

[0050] The active drive unit includes an active gear 3223 that meshes with the central locking gear and a drive main rotating shaft 3222 disposed at the center of the active gear 3223. The active gear 3223 is locked and confined to the drive main rotating shaft 3222. The drive motor 3221 drives the active gears 3223 of a set of active drive units to rotate, thereby sequentially driving the meshing central locking gear and another set of active gears 3223 to rotate.

[0051] Reference Figures 6-8 As shown, multiple sets of driven claw mechanisms 323 correspond to multiple sets of central locking gears. Each set of driven claw mechanisms 323 includes two symmetrical driven claw units disposed in the lower plate box 3213. The driven claw unit includes a guide plate 3231 mounted on the upper plate cover 3211, a double-toothed rack plate 3232 engaged in the guide groove in the guide plate 3231, and a driven gear set that drives the double-toothed rack plate 3232 to move in the guide groove in the guide plate 3231. The driven gear set meshes with the central locking gear.

[0052] For example, there are two sets of driven gears, which are respectively set on both sides of the guide plate 3231. One set of double-toothed rack plates 3232, which are opposite to the driving gear 3223, meshes with the central locking gear, and the other set meshes with the driving gear 3223. The guide plate 3231 has clearance grooves on both sides, and the driven gear sets pass through the clearance grooves and mesh with the double-toothed rack plates 3232. The driven gear sets include a drive shaft 3234 locked by the limiting plate 3215, and driven gears 3233 located at both ends of the drive shaft 3234. The driven gear 3233 located at the bottom end of the drive shaft 3234 meshes with the driving gear 3223 or the central locking gear, and the driven gear 3233 located at the bottom end of the drive shaft 3234 meshes with the double-toothed rack plates 3232.

[0053] Reference Figure 8 , 10 as well as Figure 11As shown, the longitudinal adjustment mechanism includes a supporting circumferential shaft 3241, a basic support body 3242 rotatably connected to the supporting circumferential shaft 3241, a rotating arm assembly disposed in the inner cavity of the basic support body 3242, and an angle rotation mechanism 3243 for driving the rotating arm assembly to rotate in the inner cavity of the basic support body 3242. The adsorption mechanism includes an adsorption structure 3247 and a negative pressure pump 3248. The adsorption structure 3247 is disposed on the rotating arm assembly, and the negative pressure pump 3248 is connected to the adsorption structure 3247 through a hose.

[0054] Reference Figure 11 As shown, the basic support body 3242 includes a bearing 32421 clamped onto the supporting circumferential shaft 3241, a base plate cylinder 32422 assembled onto the bearing 32421, a central rotating head 32423 clamped into the inner cavity of the base plate cylinder 32422, and three claw plates 32424 connected to the end of the central rotating head 32423 facing away from the bearing 32421; the base plate cylinder 32422 is rotatably connected to the supporting circumferential shaft 32421 via the bearing 32421. Shaft 3241, so that base plate cylinder 32422 pitches along the supporting circumferential shaft 3241, negative pressure pump 3248 is set on the surface of base plate cylinder 32422, central rotating head 32423 is subjected to external force to rotate along the central axis of base plate cylinder 32422, three claw plates 32424 are equally spaced radially along central rotating head 32423, and the central axis of claw plates 32424 is perpendicular to the axis of central rotating head 32423.

[0055] The angle rotation mechanism 3243 includes a rotary motor 32431 mounted on the base plate cylinder 32422, a rotary gear 32432 disposed at the output end of the rotary motor 32431, and a linkage gear 32433 coaxially disposed on the surface of the intermediate turn head 32423. The rotary motor 32431 drives the linkage gear 32433 and the intermediate turn head 32423 to rotate synchronously through the rotary gear 32432.

[0056] For example, an image sensor is provided at the end of the rotary head 32423 facing the workpiece to be welded. The sensor obtains the cross-sectional position of the workpiece to be welded and drives the rotary gear 32432 to rotate so that the three claw plates 32424 disposed on the rotary head 32423 abut against the surface of the workpiece to be welded with a large area.

[0057] A rotating arm assembly is mounted on each jaw plate 32424. The rotating arm assembly includes a first rotating arm 3244 fixedly mounted on the jaw plate 32424, a second rotating arm 3245 hinged to the first rotating arm 3244, and a cylinder structure 3246 for adjusting the angle between the first rotating arm 3244 and the second rotating arm 3245. One end of the cylinder structure 3246 is mounted on the first rotating arm 3244, and its output end is rotatably connected to the second rotating arm 3245. The angle between the first rotating arm 3244 and the second rotating arm 3245 is changed by the extension and retraction of the cylinder structure 3246. In addition, the first rotating arm 3244 is connected to the jaw plate 32424 perpendicular to the axis of the rotating head 32423. A plurality of silicone sensing plates 32441 are provided on the abutment plate of the first rotating arm 3244. When the first rotating arm 3244 abuts against the workpiece to be welded, the silicone sensing plates 32441 deform.

[0058] For example, a pressure sensor is provided inside the silicone sensing plate 32441, which controls the corresponding drive motor 3221 to stop rotating after sensing the set pressure.

[0059] The adsorption structure 3247 includes a base mounting plate 32471 mounted on the second rotating arm 3245, a plurality of rotating bases mounted on the base mounting plate 32471, and an adsorption head 32473 rotatably connected to the rotating base. The side of the adsorption head 32473 opposite to its adsorption end is connected to a hose.

[0060] For example, a pressure sensor is installed inside the hose.

[0061] Reference Figures 1-11 As shown, a vibration friction welding machine includes the aforementioned vibration head, and further includes: a machine tool frame, a three-axis drive structure for connecting the vibration head and the machine tool frame, and a lower mold fixture 330 mounted on the machine tool frame; the machine tool frame includes a worktable 110, two support beams 120 vertically mounted on the worktable 110, and a crossbeam 130 for connecting the two support beams 120; the three-axis drive structure includes a longitudinal drive mechanism 210 disposed on the worktable 110, a transverse drive mechanism 220 disposed on the crossbeam 130, and a lifting mechanism 230 mounted on the transverse drive mechanism 220; the lower mold fixture 330 and the upper mold fixture 320 have the same structure.

[0062] For example, the upper mold clamp 320 is configured on the lifting mechanism 230, and the lower mold clamp 330 is configured on the longitudinal drive mechanism 210.

[0063] For example, the longitudinal drive mechanism 210, the transverse drive mechanism 220 and the lifting mechanism 230 adopt a combination mechanism of servo motor with ball screw pair and linear guide rail. This mechanism is a common structure in existing machine tools and will not be described in detail here.

[0064] For example, the machine tool frame is also equipped with a control panel and a vision sensor. The control panel is used to input information such as the set pressure of the pressure sensor, the initial pressure of the workpieces to be welded rubbing against each other, and the position of the workpieces to be welded.

[0065] During operation, two plastic workpieces to be welded are clamped in the upper mold fixture 320 and the lower mold fixture 330, respectively. Specifically, the workpiece to be welded is placed in the middle position of the lower mold fixture 330; the drive motor 3221 is turned on, and the three sets of drive motors 3221 of the active drive mechanism 322 start synchronously, driving multiple sets of driven jaw mechanisms 323 to move asynchronously through the central gear set 3214. The double-toothed rack plate 3232 of the driven jaw unit slides along the guide groove of the guide plate 3231, causing the circumferentially distributed multi-point abutment mechanism 324 to gradually approach the edge of the workpiece to be welded.

[0066] When the silicone sensing plate 32441 contacts the surface of the workpiece to be welded and generates a preset deformation, the pressure sensor sends a signal to the control panel, and the drive motor 3221 stops rotating, realizing adaptive clamping of the workpiece to be welded. No less than three sets of drive motors 3221 simultaneously drive three sets of center locking gears to rotate in the same direction, so that no less than six sets of active drive units meshing with them are driven.

[0067] In the process of clamping the workpiece to be welded, the image sensor acquires the cross-sectional position of the workpiece to be welded, and then controls the rotation of the rotary gear 32432. The rotary motor 32431 drives the linkage gear 32433 and the intermediate turn head 32423 to rotate synchronously through the rotary gear 32432, so that the three jaw plates 32424 arranged on the intermediate turn head 32423 abut against the surface of the workpiece to be welded with a large area. As the jaw plates 32424 gradually approach the workpiece to be welded, the workpiece to be welded and the jaw plates 32424 abut against each other and generate a reaction force. This reaction force drives the intermediate turn head 32423 and the base plate cylinder 32422 to adjust their angle adaptively with the pitch of the supporting circumferential shaft 3241, so that the jaw plates 32424 face the surface of the workpiece to be welded.

[0068] After the silicone sensing plate 32441 is pressed against the surface of the workpiece to be welded with constant pressure, the cylinder structure 3246 drives the second rotating arm 3245 to rotate around its hinge point with the first rotating arm 3244, causing the multiple adsorption heads 32473 arranged on the second rotating arm 3245 to abut against the surface of the workpiece to be welded. When the adsorption head 32473 approaches the workpiece to be welded, its built-in angle sensor monitors the contact angle between the adsorption head 32473 and the workpiece surface in real time, and drives the rotating base to make fine adjustments through the feedback system, so that the adsorption head 32473 adaptively fits the workpiece surface.

[0069] The negative pressure pump 3248 is connected to the adsorption head 32473 via a flexible hose. Its operating status is dynamically adjusted by the control system based on the actual adsorption situation of the adsorption head 32473. When all adsorption heads 32473 are tightly attached to the surface of the workpiece to be welded, the air pressure sensor inside the hose detects the formation of a sealed space. When the air pressure reaches the preset negative pressure threshold, the control system determines that the workpiece has been completely adsorbed. At this time, the negative pressure pump 3248 switches to a pressure stabilization mode, continuously outputting a stable negative pressure to maintain a fixed pressure for adsorbing the workpiece and ensuring that the workpiece does not shift during the welding process.

[0070] If the surface of the workpiece to be welded is uneven, resulting in only some of the suction heads 32473 not being fully in contact with the workpiece, air will continuously enter the hose, causing the air pressure value to fail to reach the preset threshold. In this case, the air pressure sensor will feed back the real-time air pressure data to the control panel, and the control system will maintain negative pressure in the hose. The negative pressure pump 3248 will operate at full load, continuously extracting air, ensuring that all suction heads 32473 are tightly in contact with the workpiece surface, thus clamping the workpiece to be welded.

[0071] After both sets of workpieces to be welded are clamped, the longitudinal drive mechanism 210, the transverse drive mechanism 220, and the lifting mechanism 230 combine the two workpieces with a constant initial pressure, and then the electromagnetic vibration device is activated. The vibration source alternately inputs high-frequency current into the electromagnetic coils 3121 in the left and right chambers, causing the electromagnetic coils 3121 to generate a periodically changing electromagnetic field. Under the synergistic effect of the electromagnetic field and the plate spring 3123, the drive armature 3122 drives the vibrating plate 3124 to perform horizontal reciprocating motion at a frequency of 280-380Hz and an amplitude of 0.1-1.2mm. The vibration energy is transferred to the welding surface of the workpiece through the upper mold fixture 320, generating frictional heat between the contact surfaces. After reaching the melting point of the plastic, friction welding is achieved.

[0072] The active drive mechanism 322 of this application drives the driven jaw mechanism 323 to move asynchronously through the central gear set 3214 and the active drive mechanism 322. This, in turn, drives the multi-point contact mechanism 324 to achieve adaptive fitting of different clamping surfaces according to the differences in the workpiece shape, so that the workpiece to be welded has a certain clamping area from multiple angles and provides a certain clamping force. Combined with the pitch and rotation functions of the longitudinal distance adjustment mechanism and the flexible angle adjustment characteristics of the adsorption mechanism, it can accurately match various irregularly shaped workpieces, solving the problem that traditional fixtures cannot cope with the complex shapes of different workpieces to be welded. Secondly, the adsorption mechanism ensures that the workpiece remains stably clamped during the welding process through real-time monitoring and dynamic control of the negative pressure pump 3248 and the air pressure sensor, avoiding welding defects caused by displacement. The silicone induction plate 32441 has a built-in pressure sensor, which can accurately control the clamping force of the fixture, prevent the workpiece from deforming due to overpressure, and ensure the dimensional accuracy and strength of the welded part. Through magnetic attraction and clamping, the workpiece to be welded has sufficient clamping force to ensure the stability of the workpiece.

[0073] Of course, the above description is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the embodiments of the present invention. The present invention is also not limited to the above examples, and all equivalent changes and improvements made by those skilled in the art within the scope of the present invention should fall within the patent coverage of the present invention.

[0074] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", and "linkage" should be interpreted broadly, and can be mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change.

[0075] Secondly: The accompanying drawings of the embodiments disclosed in this invention only involve the structures involved in the embodiments disclosed in this invention. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this invention can be combined with each other.

[0076] In conclusion, the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A vibrating head, comprising a displacement driving mechanism (310) and an upper mold clamp (320), characterized in that: The displacement driving mechanism (310) includes a vibrating head frame and two sets of electromagnetic vibration devices arranged symmetrically in the inner cavity of the vibrating head frame. The electromagnetic vibration device includes a plate spring (3123), a driving armature (3122), and an electromagnetic coil (3121) arranged from the center of the vibrating head frame to the end. The driving armature (3122) extends out of the inner cavity of the vibrating head frame and is connected to a vibrating plate (3124). The end of the electromagnetic coil (3121) away from the driving armature (3122) is connected to a vibration source for alternately inputting electrical energy into the electromagnetic coil (3121). The upper mold fixture (320) includes a positioning chuck (321), an active drive mechanism (322) disposed in the positioning chuck (321), multiple sets of driven jaw mechanisms (323) arranged circumferentially on the surface of the positioning chuck (321), and a multi-point abutment mechanism (324) connected to the free end of the driven jaw mechanism (323). The multi-point abutment mechanism (324) includes a longitudinal adjustment mechanism and an adsorption mechanism. The active drive mechanism (322) drives the multiple sets of driven jaw mechanisms (323) to move asynchronously so that the multi-point abutment mechanism (324) abuts against different clamping surfaces of the workpiece to be welded. The positioning chuck (321) includes a lower plate box (3213), an upper plate cover (3211) mounted on the lower plate box (3213), a central mounting cylinder (3212) extending downward from the center of the upper plate cover (3211), and a central gear set (3214) engaged with the central mounting cylinder (3212); wherein, the central gear set (3214) includes no less than three sets of central locking gears stacked along the axial direction of the lower plate box (3213), and the central locking gears rotate around the axis of the lower plate box (3213) under the action of external force; The number of active drive mechanisms (322) is not less than three sets, which are used to drive not less than three sets of center locking gears respectively; The longitudinal adjustment mechanism includes a supporting circumferential shaft (3241), a basic support body (3242) rotatably connected to the supporting circumferential shaft (3241), a rotating arm assembly disposed in the inner cavity of the basic support body (3242), and an angle rotation mechanism (3243) for driving the rotating arm assembly to rotate in the inner cavity of the basic support body (3242). The adsorption mechanism includes an adsorption structure (3247) and a negative pressure pump (3248). The adsorption structure (3247) is disposed on the rotating arm assembly, and the negative pressure pump (3248) is connected to the adsorption structure (3247) through a hose.

2. The vibrating head as described in claim 1, characterized in that: The active drive mechanism (322) includes two sets of active drive units symmetrically arranged in the lower plate box (3213), and one set of the active drive units is engaged with a drive motor (3221); the active drive unit includes an active gear (3223) that meshes with the central locking gear and a drive main rotating shaft (3222) arranged at the center of the active gear (3223).

3. The vibrating head as described in claim 2, characterized in that: Each set of driven claw mechanisms (323) includes two symmetrical driven claw units disposed in the lower plate box (3213). The driven claw unit includes a guide plate (3231) mounted on the upper plate cover (3211), a double-toothed rack plate (3232) engaged in the guide groove in the guide plate (3231), and a driven gear set that drives the double-toothed rack plate (3232) to move in the guide groove of the guide plate (3231). The driven gear set meshes with the central locking gear.

4. The vibrating head as described in claim 3, characterized in that: The basic support body (3242) includes a bearing seat (32421) snapped onto a supporting circumferential shaft (3241), a base plate cylinder (32422) assembled onto the bearing seat (32421), a central rotating head (32423) snapped into the inner cavity of the base plate cylinder (32422), and three claw plates (32424) connected to the end of the central rotating head (32423) facing away from the bearing seat (32421); the base plate cylinder (32422) is rotatably connected to the supporting circumferential shaft through the bearing seat (32421). (3241), so that the base plate cylinder (32422) pitches along the supporting circumferential axis (3241), the negative pressure pump (3248) is disposed on the surface of the base plate cylinder (32422), the central rotating head (32423) is subjected to external force and rotates along the central axis of the base plate cylinder (32422), the three claw plates (32424) are equally spaced along the radial direction of the central rotating head (32423), and the central axis of the claw plates (32424) is perpendicular to the axis of the central rotating head (32423).

5. The vibrating head as described in claim 4, characterized in that: The angle rotation mechanism (3243) includes a rotary motor (32431) mounted on the base plate cylinder (32422), a rotary gear (32432) disposed at the output end of the rotary motor (32431), and a linkage gear (32433) coaxially disposed on the surface of the intermediate turn head (32423). The rotary motor (32431) drives the linkage gear (32433) and the intermediate turn head (32423) to rotate synchronously through the rotary gear (32432).

6. The vibrating head as described in claim 5, characterized in that: The rotating arm assembly is disposed on each claw plate (32424). The rotating arm assembly includes a first rotating arm (3244) fixedly mounted on the claw plate (32424), a second rotating arm (3245) hinged to the first rotating arm (3244), and a cylinder structure (3246) for driving the angle adjustment between the first rotating arm (3244) and the second rotating arm (3245).

7. The vibrating head as described in claim 6, characterized in that: The adsorption structure (3247) includes a base mounting plate (32471) mounted on the second rotating arm (3245), a plurality of rotating bases mounted on the base mounting plate (32471), and an adsorption head (32473) rotatably connected to the rotating base. The side of the adsorption head (32473) opposite to its adsorption end is connected to a hose.

8. A vibration friction welding machine, comprising a vibration head as described in any one of claims 1-7, characterized in that, Also includes: Machine tool frame, a three-axis drive structure for connecting the vibrating head and the machine tool frame, and a lower mold fixture (330) mounted on the machine tool frame.

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