A friction stir welding tool for large diameter cylinders

Abstract

This invention belongs to the field of friction stir welding technology, and in particular, relates to a friction stir welding fixture for large-diameter cylinders. The fixture comprises an outer circumferential positioning device for encircling the cylinder, a mounting mechanism for mounting an inlet block and an outlet block, a drive device for supporting the cylinder and driving its circumferential rotation, and a base plate. The outer circumferential positioning device, mounting mechanism, and drive device are all mounted on the base plate. This welding fixture is designed for use with the friction stir welding process, significantly improving welding efficiency and weld quality for large-diameter cylinders.

Description

Technical Field

[0001] The invention belongs to the technical field of friction stir welding, and in particular relates to a friction stir welding tool for a large-diameter cylinder. Background Art

[0002] Friction welding is a method that uses the heat generated by the mutual movement and friction between the end faces of the workpieces to make the ends reach a thermoplastic state, and then quickly forge them to complete the welding. The friction stir welding (FSW) process is that a stirring pin (welding pin) of a cylinder or other shape (such as a threaded cylinder) is inserted into the joint of the workpiece. Through the high-speed rotation of the welding head, it rubs against the welding workpiece material, thereby raising the temperature of the material at the connection and softening it, and at the same time stirring and rubbing the material to complete the welding. Because friction stir welding (FSW) has the characteristics of high welding quality, fast welding efficiency, no need for welding materials, energy saving and environmental protection; at the same time, friction stir welding has process characteristics such as large forging force and large opening force, the application range of friction stir welding is becoming more and more extensive.

[0003] When preparing a large-diameter cylinder, after the cylinder is rolled into a circle by a plate rolling machine, there will be a seam in the middle, called a longitudinal seam. The existing welding of the longitudinal seam is done by manual arc welding, which has low efficiency and poor weld quality.

[0004] Therefore, there is an urgent need for a friction stir welding tool for large-diameter cylinders to solve the above problems. Summary of the Invention

[0005] In order to overcome the above-mentioned defects in the prior art, the present invention provides a friction stir welding tool for large-diameter cylinders. The welding tool is designed to be compatible with the friction stir welding process, greatly improving the welding efficiency and weld quality of large-diameter cylinders.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A friction stir welding tool for a large-diameter cylinder includes an outer embracing positioning device for embracing the cylinder, a mounting mechanism for mounting an introduction block and an exit block, a driving device for supporting the cylinder and driving the cylinder to rotate circumferentially, and a base plate; the outer embracing positioning device, the mounting mechanism, and the driving device are all mounted on the base plate;

[0008] The outer embracing positioning device includes an embracing hoop for embracing the cylinder, a first driving assembly for driving the embracing hoop to open and close radially, and a floating pressing assembly for pressing the cylinder; the first driving assembly is distributed on both sides of the open end of the embracing hoop, and the open end forms a working gap for the stirring needle to extend into;

[0009] The mounting mechanism includes a weld support seat, a first fixing device, and a second fixing device, wherein the first fixing device and the second fixing device are respectively mounted on two ends of the weld support seat; the first fixing device includes an adjusting member for pushing the lead-in block toward the weld, and the second fixing device includes an adjusting assembly for pushing the lead-out block toward the weld, so that the lead-in block and the lead-out block can exert force on each other to clamp the cylinder, at which time, the adjacent ends of the lead-in block and the lead-out block are respectively in close contact with the two ends of the weld;

[0010] The driving device includes a frame, the inner cavity of the frame constitutes a working chamber in which the cylinder can be placed to limit the height of the cylinder, and a plurality of second driving components for driving the cylinder in the working chamber to produce circumferential rotation and a pre-positioning baffle that can limit the position of the cylinder are arranged in the working chamber; the pre-positioning baffle is set at the working chamber and is in an arc shape convex toward the cylinder.

[0011] Preferably, the hoop is formed by hingedly connecting two semicircular hoop bodies, and the non-hinged ends of the two semicircular hoop bodies constitute open ends; the driving source of the first driving assembly is connected to the outer wall of the hoop.

[0012] Preferably, the adjustment assembly includes a first wedge block and a second wedge block with matching wedge surfaces; the first wedge block is connected to the pushing member so that the first wedge block can move perpendicular to the weld; the lead-out block is placed above the second wedge block in the height direction, and when the pushing member pushes the first wedge block to move, the wedge surface cooperates to push the second wedge block upward, thereby generating a lifting drive action for the lead-out block.

[0013] Preferably, the driving device also includes a plurality of follower components arranged along the circumference of the cylinder, and the pre-positioning baffle is located on the follower component; the bottom of the second driving component and the bottom of the follower component are both provided with adjustment components for realizing radial height adjustment of the corresponding components; the adjustment component includes a third wedge block, two fourth wedge blocks adapted to the wedge surface of the bottom of the third wedge block and an adjusting screw, the adjusting screw passes through the two fourth wedge blocks and causes the two fourth wedge blocks to move toward or away from each other.

[0014] Preferably, the first driving component includes a driving source and a mounting bracket, a through hole is opened on the mounting bracket, and the driving source is movably installed in the through hole, thereby realizing the horizontal swinging movement of the driving source; the telescopic end of the driving source extends out of the through hole, and the telescopic end fixing sleeve of the driving source is provided with a connecting sleeve, the outer wall of the connecting sleeve is hinged to the first hinge seat through a first pin shaft, and a push plate is integrally formed on the outer wall of the open end of the clamp, and the first hinge seat and the push plate are detachably connected.

[0015] Preferably, the floating clamping assembly includes a plurality of clamping strips installed at intervals on the inner wall of the clamping hoop, a clamping block located on the inner side of the open ends of the two semicircular hoop bodies, and an adjusting screw passing through the ends of the open ends of the two semicircular hoop bodies; the adjusting screw is located at one end on the inner side of the semicircular hoop body and is fixedly connected to the clamping block; the adjusting screw is located at one end on the outer side of the semicircular hoop body and is sleeved with a pre-tightening spring; the end face of the clamping block close to the semicircular hoop body is arc-shaped; the open ends of the two semicircular hoop bodies are both provided with wedge surfaces extending from the inside to the outside, and a plurality of clamping blocks are arranged at intervals along the height direction of the semicircular hoop body; the driving source is installed on the second hinge seat, and the second hinge seat is connected to the inner wall of the through hole by a rotating shaft, so that the driving source can swing horizontally; the driving source is arranged in a plurality of directions along the height direction of the mounting bracket; the hinged ends of the two semicircular hoop bodies are hinged to the support ear seat by a second pin shaft.

[0016] Preferably, the second fixing device also includes an adjusting fixing seat fixedly connected to the weld support seat, a second groove is opened on the adjusting fixing seat toward the weld, the first wedge block, the second wedge block and the lead-out block are placed in the second groove in sequence along the length direction of the weld, the pushing member is a rotating screw, and the adjusting fixing seat is provided with a first through-hole perpendicular to the weld, the rotating screw passes through the first through-hole and is threadedly connected to the first threaded hole on the first wedge block; two first limit blocks are fixed on the pushing member for limiting axial movement of the pushing member, and the two first limit blocks are distributed at both ends of the first through-hole; the bottom of the weld support seat is fixedly mounted on the base plate.

[0017] Preferably, the first fixing device also includes a flip body hinged to the weld support seat and a fixing assembly for fixing the flip body, the flip body is provided with a first groove with an opening facing the weld, the introduction block is placed in the first groove, the adjusting member is a first top screw, and the pushing end of the adjusting member is placed in the first groove and contacts with the introduction block; the fixing assembly includes a latch, a latch limiting seat for limiting the latch, and a latch fixing seat, the latch limiting seat is fixed to the flip body, the latch fixing seat is fixed to the weld support seat, the fixed end of the latch passes through the latch limiting seat and is detachably connected to the latch fixing seat; the fixing sleeve on the latch is provided with a limiting ring for limiting axial movement of the latch, the limiting ring The ring is placed in the latch limit seat; a second through-hole is provided on the latch limit seat, and a third through-hole is provided on the latch fixing seat. The fixed end of the latch passes through the second through-hole and is connected to the third through-hole, and the central axis of the third through-hole is collinear with the central axis of the second through-hole; a plurality of glass bead screws are provided on the latch fixing seat, and one end of the glass bead screw with a glass bead is placed in the third through-hole, and the glass bead screw is elastically engaged with the slot embedded in the fixed end of the latch; an operating ball is provided on the end of the latch away from the latch fixing seat; a spring is also provided on the latch, and the spring is connected to the side of the limit ring close to the latch fixing seat; a limit screw is also provided on the flip body; the weld support seat is against the non-welding side of the weld.

[0018] Preferably, a third threaded hole is provided inside the two fourth wedge blocks, and the thread directions of the two third threaded holes are opposite; the two ends of the adjusting screw are threadedly connected to the two third threaded holes respectively; the driving device also includes a base, on which a screw limit seat is fixed, and the adjusting screw is provided with two second limit blocks for limiting axial movement of the adjusting screw, and the screw section of the adjusting screw located between the two second limit blocks passes through the screw limit seat; one end of the adjusting screw is transmission-connected to the second driving motor; the wedge surfaces at both ends of the bottom of the third wedge block are both inclined and extend upward from the inside to the outside, and the wedge surface at the top of the fourth wedge block is adapted to the wedge surface at the bottom of the third wedge block; a pressure sensor is installed on the contact wedge surface between the fourth wedge block and the third wedge block.

[0019] Preferably, the second driving assembly includes an active roller for supporting the cylinder, a first mounting frame for mounting the active roller, and a first driving motor for driving the active roller to rotate; the follower assembly includes a follower roller for supporting the cylinder and a second mounting frame for mounting the follower roller; the bottom of the first mounting frame and the bottom of the second mounting frame are both fixedly connected to the side of the third wedge away from the fourth wedge.

[0020] The advantages of the present invention are:

[0021] (1) The welding tool provided by the present invention can be used in conjunction with the stir friction welding process, which greatly improves the welding efficiency and weld quality of large-diameter cylinders; the outer ring positioning device provided in the tool is provided with an openable and closable clamp and a first drive component; the clamping mechanism is convenient for disassembling and assembling the introduction block and the lead-out block and for adjusting the positions of the introduction block and the lead-out block by providing the first fixing device and the second fixing device, so that the introduction block and the lead-out block can be tightly attached to the cylinder, and when performing longitudinal seam welding, the introduction block can be pierced and welded first, and finally the lead-out block can be welded, thereby ensuring that all longitudinal seams are welded, improving the welding quality, and convenient operation; the first drive component can drive the clamp to tighten or open, and can clamp, position, and control the size of the longitudinal seam of the cylinder, which helps to ensure the welding effect of stir friction welding.

[0022] (2) In the driving device of the present invention, the cylinder is placed on the active roller and the follower roller, so that when the active roller rotates, the cylinder on it can be driven to move, thereby achieving the purpose of rapid movement of the cylinder, and the position of the cylinder weld can be kept consistent with the position of the welding needle of the stirring head; an arc-shaped pre-positioning baffle is provided to guide the rapid placement of the cylinder and limit the cylinder to prevent it from moving out; by rotating the adjusting screw, the two fourth wedges are driven to move toward or away from each other, which is convenient for adjusting the height of the cylinder, and can make the longitudinal weld of the workpiece to be welded perpendicular to the horizontal plane, which is conducive to ensuring the welding effect.

[0023] (3) Two wedge-shaped first wedge blocks and a second wedge block are provided in the clamping mechanism of the present invention, so that when the pusher (rotating screw) rotates, the first wedge block can be moved in a direction perpendicular to the length of the weld, thereby pushing the second wedge block to move in the length direction of the weld, thereby realizing the movement of the lead-out block in the length direction of the weld, making it easier for the lead-out block to be tightly attached to the end of the weld, and since the cylinder is arranged vertically, the second fixing device is provided to facilitate the application of force to the first wedge block, so that the lead-out block moves toward the weld.

[0024] (4) The follower assembly provided in the present invention can assist the second drive assembly in driving the cylinder to move, thereby realizing easy movement of the cylinder; the provided latch limit seat and latch fixing seat make the loading and unloading of the introduction block more convenient, thereby greatly improving work efficiency; the latch can be disengaged and fixed by only pulling or pushing the operating ball, thereby making the loading and unloading of the introduction block more convenient, thereby greatly improving work efficiency.

[0025] (5) The arc-shaped pressing block provided in the present invention allows the pressing block to swing, so that the pressing block can better fit the cylinder; the pre-tightening of the pre-tightening spring facilitates the pressing block to fit tightly with the clamp; the provided adjusting screw facilitates tightening the pressing block, thereby increasing the contact area between the pressing block and the cylinder and ensuring the pressing force. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0027] Figure 2 It is a structural schematic diagram of the outer encircling positioning device of the present invention.

[0028] Figure 3 This is a schematic structural diagram of the first drive assembly of the present invention.

[0029] Figure 4 It is a schematic diagram of the top view of the outer encircling positioning device of the present invention.

[0030] Figure 5 This is an enlarged structural diagram of the compression block of the present invention.

[0031] Figure 6 It is a schematic diagram of the installation mechanism structure of the present invention.

[0032] Figure 7 This is a structural schematic diagram of the weld support seat of the present invention.

[0033] Figure 8 The present invention introduces a schematic diagram of a partially enlarged structure of a block.

[0034] Figure 9 It is a schematic diagram of the cross-sectional structure of the latch limiting seat of the present invention.

[0035] Figure 10 It is a schematic diagram of the cross-sectional structure of the fixing seat of the present invention.

[0036] Figure 11 It is a schematic structural diagram of the driving device of the present invention.

[0037] Figure 12 This is a schematic structural diagram of the second drive assembly of the present invention.

[0038] Figure 13 It is a schematic cross-sectional structural diagram of the second drive assembly of the present invention.

[0039] Figure 14 It is a schematic diagram of the overall structure of the follower assembly of the present invention.

[0040] Figure 15 It is a schematic diagram of the cross-sectional structure of the follower assembly of the present invention.

[0041] The meanings of the symbols in the figure are as follows:

[0042] 1-outer encircling positioning device, 11-holding hoop, 111-push plate, 112-semicircular hoop body, 12-first drive assembly, 121-drive source, 122-mounting bracket, 1221-through hole, 123-connecting sleeve, 124-first hinge seat, 131-pressing strip, 132-pressing block, 133-adjusting screw, 134-preload spring, 14-support ear seat, 15-second hinge seat;

[0043] 2-installation mechanism, 21-weld support seat, 22-introduction block, 23-extraction block, 24-first fixing device, 241-flip body, 2411-first groove, 242-adjusting member, 243-limiting screw, 25-fixing assembly, 251-latch limiting seat, 2511-second through-hole, 252-latch fixing seat, 2521-third through-hole, 253-latch, 2531-slot, 26-bead screw, 27-second fixing device, 271-adjusting fixing seat, 2711-second groove, 272-adjusting assembly, 2721-pushing member, 2722-first wedge block, 2723-second wedge block, 273-first threaded hole, 274-first limiting block, 275-first through-hole, 28-operating ball, 291-limiting ring;

[0044] 3-driving device, 31-second driving assembly, 311-driving roller, 312-first driving motor, 313-first mounting bracket, 32-following assembly, 321-following roller, 322-pre-positioning baffle, 323-second mounting bracket, 33-adjusting assembly, 331-third wedge block, 332-fourth wedge block, 3321-third threaded hole, 333-adjusting screw, 3331-second limiting block, 334-screw limiting seat, 34-base;

[0045] 4- Bottom plate. DETAILED DESCRIPTION

[0046] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of the present invention.

[0047] like Figure 1 As shown, a friction stir welding fixture for large-diameter cylinders is used for positioning, clamping, supporting, and adjusting the weld seam during friction stir welding (FSW) of large-diameter, thick-walled cylinders (approximately 2 meters in outer diameter, 52 mm in thickness, and other specifications). The fixture comprises an outer embracing positioning device 1 that encircles the cylinder, a mounting mechanism 2 for mounting an inlet block 22 and an outlet block 23 and clamping the weld seam of the cylinder, a drive device 3 for rotating the cylinder, and a base plate 4. The outer embracing positioning device 1, mounting mechanism 2, and drive device 3 are all mounted on base plate 4.

[0048] like Figure 2-5 As shown, the outer encircling positioning device 1:

[0049] It includes a clamp 11, a first drive component 12 and a floating clamping component. The first drive component 12 is distributed on both sides of the open end of the clamp 11. The open end constitutes a working gap for the stirring needle to extend into. The clamp 11 includes two semicircular hoop bodies 112. The hinged ends of the two semicircular hoop bodies 112 are hinged to the supporting ear seat 14 through a second pin shaft. The non-hinged ends of the two semicircular hoop bodies 112 are open ends. The open ends of the two semicircular hoop bodies 112 have wedge surfaces extending from the inside to the outside, and the open ends are in the shape of an "eight", which is convenient for increasing the welding space and thus facilitating welding to align the longitudinal seam.

[0050] The first drive assembly 12 includes a drive source 121 and a mounting bracket 122. The bottom of the mounting bracket 122 is fixedly mounted on the base plate 4. The mounting bracket 122 is provided with a through hole 1221. The drive source 121 is mounted on a second hinged seat 15. The second hinged seat 15 is connected to the inner wall of the through hole 1221 via a rotating shaft, allowing the drive source 121 to rotate in a horizontal plane. The telescopic end of the drive source 121 extends out of the through hole 1221, and the telescopic end of the drive source 121 is fixedly sleeved with a connecting sleeve 123. The outer wall of the connecting sleeve 123 is hinged to the first hinged seat 124 via a first pin. A push plate 111 is provided on the outer wall of the open end of the clamp 11. The first hinged seat 124 is detachably connected to the threaded hole in the push plate 111 via screws. The drive source 121 is provided with several screws along the height direction of the mounting bracket 122 to facilitate flexible engagement with the clamp 11.

[0051] Since the weld is subjected to great force during welding, the push plate 111 of the clamp 11 is formed as an integral machined part, that is, the push plate 111 and the clamp 11 are integrally formed and have a solid structure, which can avoid the problem of insufficient connection strength caused by welding quality.

[0052] The floating clamping assembly includes a plurality of clamping strips 131 installed at intervals on the inner wall of the clamping hoop 11, a clamping block 132 located inside the open ends of the two semicircular hoop bodies 112, and an adjusting screw 133 that passes through the ends of the open ends of the two semicircular hoop bodies 112. The adjusting screw 133 is located on one end inside the semicircular hoop body 112 and is fixedly connected to the clamping block 132. Several clamping blocks 132 are arranged at intervals along the height direction of the semicircular hoop body 112 to ensure that the clamping blocks 132 can fully contact the cylinder. The end face of the clamping block 132 close to the semicircular hoop body 112 is arc-shaped, so that the clamping block 132 can swing, so that the clamping block 132 can better fit the cylinder.

[0053] When the clamping block 132 is not in contact with the cylinder, by tightening the adjusting screw 133, the adjusting screw 133 drives the clamping block 132 toward the cylinder until the clamping block 132 contacts the cylinder, thereby ensuring that the clamping block 132 contacts the cylinder and the clamping force is maintained. A preload spring 134 is sleeved on one end of the adjusting screw 133 located outside the semicircular hoop body 112. The preload spring 134 is preloaded to facilitate the close contact between the clamping block 132 and the clamping hoop.

[0054] During operation, the drive source 121 is a hydraulic cylinder. The mounting bracket 122 is provided with a plurality of through-holes 1221, within which the hydraulic cylinder is mounted, allowing it to rotate along the axis. A floating gap is reserved above and below the first hinged seat 124 and the connecting sleeve 123 to ensure the hydraulic cylinder's freedom of movement and prevent mutual interference. Driven by the hydraulic cylinder, the clamp 11 can rotate about the axis. When the two semicircular hoop bodies 112 are tightened (closed), the multiple compression blocks 132 and compression strips 131 distributed on the clamp 11 compress the cylinder. Shims can be installed between the compression strips 131 and the clamp 11 to ensure full contact between the compression strips 131 and the cylinder.

[0055] like Figure 6-10 As shown, the installation mechanism 2:

[0056] Used to fix and push the lead-in block 22 and the lead-out block 23. The mechanism includes a weld support seat 21, a first fixing device 24, and a second fixing device 27. The bottom of the weld support seat 21 is fixedly mounted on the base plate 4; the first fixing device 24 includes a flip body 241, a fixing assembly 25 for fixing the flip body 241, and an adjusting member 242; the second fixing device 27 includes an adjusting fixing seat 271 fixedly connected to the weld support seat 21 and an adjusting assembly 272 for moving the lead-out block 23 along the weld direction, so that the lead-in block 22 and the lead-out block 23 can apply force to each other to clamp the cylinder. At this time, the adjacent ends of the lead-in block 22 and the lead-out block 23 are respectively close to the two ends of the weld.

[0057] Specifically, the flip body 241 is placed on the top of the weld support seat 21 and is hinged to the weld support seat 21 through a rotating shaft. A first groove 2411 with an opening facing the weld is provided on the flip body 241, and the introduction block 22 is fixed in the first groove 2411 by a third top screw on the side wall of the first groove 2411; the adjustment fixing seat 271 is fixedly placed on the bottom of the side wall of the weld support seat 21 and the non-welding surface of the weld, and the flip body 241 and the adjustment fixing seat 271 are located on the same side wall of the weld support seat 21.

[0058] like Figure 6-7 As shown, when welding the weld in a vertical direction, the side surface of the weld support seat 21 is in the shape of a right-angled trapezoid, and the sidewall of the right-angled side of the weld support seat 21 is an arc-shaped surface, namely the sidewall of the weld support seat 21 located between the lead-in block 22 and the lead-out block 23. This allows the weld support seat 21 to more closely contact the weld surface, and the sidewall is used to abut against the non-welding side of the weld. When welding the weld in a horizontal direction, the weld support seat 21 can be in the shape of a flat rectangular parallelepiped.

[0059] like Figure 8-9 As shown, the adjusting member 242 is a first top screw, and the flip body 241 is in a "7" shape, that is, the flip body 241 is composed of a horizontal plate and a vertical plate, the horizontal plate is arranged perpendicular to the length of the weld, and the vertical plate is parallel to the length of the weld. The first groove 2411 is located on the vertical plate, and the first groove 2411 opens into a "U" shape toward the weld. A first threaded hole is provided at the first groove 2411 of the vertical plate. The first top screw passes through the first groove 2411 and is threadedly connected to the first threaded hole. The first threaded hole is arranged along the length of the weld, so that when the first top screw is twisted, the end of the first top screw pushes the introduction block 22 to move along the length of the weld, thereby making the introduction block 22 fit the end of the weld. At the same time, the shape of the introduction block 22 is adapted to the shape of the first groove 2411, and a third top screw is threadedly connected to each side wall of the first groove 2411. The end of the third top screw contacts the introduction block 22, which is convenient for further fixing the introduction block 22 after the introduction block 22 fits the end of the weld.

[0060] The fixing assembly 25 includes a latch 253, a latch limiting seat 251 for limiting the latch 253, and a latch fixing seat 252; the latch fixing seat 252 is fixed to the two side walls of the weld support seat 21, and one end of the latch 253 passes through the latch limiting seat 251 and is detachably connected to the latch fixing seat 252.

[0061] A latch stopper 251 is fixedly mounted on both outer side walls of the vertical plate of the flip body 241. The latch stopper 251 is provided with a second through-hole 2511. The latch fixing seat 252 is provided with a third through-hole 2521. The fixed end of the latch 253 passes through the second through-hole 2511 and is connected to the third through-hole 2521. The central axis of the third through-hole 2521 is collinear with the central axis of the second through-hole 2511. A limiting ring 291 is fixedly sleeved on the latch 253. The apertures at both ends of the second through-hole 2511 are smaller than the aperture of the middle section. The outer diameter of the limiting ring 291 is larger than the aperture at the end of the second through-hole 2511. The outer diameter of the limiting ring 291 is smaller than the aperture of the middle section. The aperture of the middle section of the second through-hole 2511 allows the limiting ring 291 to be confined within the second through-hole 2511, thereby preventing the latch 253 from falling out of the latch limiting seat 251; a plurality of bead screws 26 (wave screws) are provided on the latch fixing seat 252, and one end of the bead screw 26 with a glass bead is placed in the third through-hole 2521. The bead screw 26 is elastically engaged with the groove 2531 embedded in the fixed end of the latch 253. When the latch 253 is inserted into the third through-hole 2521, the glass bead on the bead screw 26 (wave screw) will be stuck in the corresponding groove 2531 on the latch 253, thereby playing a limiting role.

[0062] An operating ball 28 is provided at one end of the latch 253 away from the latch fixing seat 252. The size of the operating ball 28 is larger than the diameter of the latch 253, which facilitates pulling the latch 253 and improves convenience of use.

[0063] A spring is also sleeved on the latch 253, which is located in the second through-hole 2511 and on the side of the limiting ring 291 close to the latch fixing seat 252; when it is necessary to fix the introduction block 22, the operating ball 28 is pushed so that the slot 2531 on the latch 253 engages with the bead screw 26, and the spring is in a compressed state; when welding is completed, the operating ball 28 is pulled, and under the action of the spring, the latch 253 is disengaged from the latch fixing seat 252, and the latch 253 retracts, avoiding interference between the latch 253 and the latch fixing seat 252.

[0064] A limit screw 243 is also provided on the flip body 241, and the limit screw 243 is installed on the horizontal plate of the flip body 241. When the flip body 241 is flipped down, the limit screw 243 thereon will contact the top surface of the weld support seat 21, thereby limiting and adjusting the position. By turning the limit screw 243, the center axis of the pin 253 can be made to coincide with the center axis of the third through-hole 2521, thereby limiting the position of the flip body 241 along the length direction of the weld, and ensuring that the pin 253 can be accurately inserted into the third through-hole 2521.

[0065] Furthermore, if Figure 6 and Figure 10 As shown, a second groove 2711 with an opening facing the weld is provided on the adjustment fixing seat 27, and the adjustment component 272 and the lead-out block 23 are sequentially placed in the second groove 2711 along the length direction of the weld.

[0066] Adjustment assembly 272 includes a pusher 2721 (which may be a rotating screw), a first wedge 2722, and a second wedge 2723. The contacting wedge surfaces of first wedge 2722 and second wedge 2723 are aligned, forming a square. First wedge 2722, second wedge 2723, and lead-out block 23 are sequentially positioned within second groove 2711 along the length of the weld. The contact surface between second wedge 2723 and lead-out block 23 is flat, ensuring stable movement of lead-out block 23 when second wedge 2723 moves.

[0067] The adjusting fixing seat 271 is also provided with a first through-hole 275 perpendicular to the weld, and the rotating screw passes through the first through-hole 275 and is threadedly connected to the first threaded hole 273 on the first wedge block 2722; two first limit blocks 274 are fixed on the rotating screw, and the two first limit blocks 274 are distributed at both ends of the first through-hole 275, so that when the rotating screw is turned, the rotating screw only rotates on its own, and the first wedge block 2722 threadedly connected to the rotating screw can move in a direction perpendicular to the length of the weld, thereby pushing the second wedge block 2723 to move along the length of the weld, so that the lead-out block 23 moves along the length of the weld.

[0068] A plurality of second threaded holes are provided on the side wall of the second groove 2711 , and the second threaded holes are threadedly connected to the second top screws, and the ends of the second top screws are in contact with the lead-out block 23 . Twisting the second top screws can fix the lead-out block 23 in the second groove 2711 .

[0069] like Figure 11-15 As shown, the drive device 3:

[0070] It includes a frame, several second drive components 31, several follower components 32, several adjustment components 33, a pre-positioning baffle 322 and a base 34. The inner cavity of the frame constitutes a working chamber for the cylinder to be placed in, thereby limiting the height of the cylinder. Several second drive components 31 are arranged at the wall of the working chamber, and are used to drive the cylinder at the working chamber to produce circumferential rotation. The bottom of the second drive component 31 and the bottom of the follower component 32 are both provided with adjustment components 33. The adjustment components 33 can adjust the height of the corresponding second drive component 31 and follower component 32. Several adjustment components 33 are installed on the corresponding base 34, and the bottom of the base 34 is fixedly installed on the bottom plate 4.

[0071] Specifically, such as Figure 11-15 As shown, the second drive assembly 31 consists of a driving roller 311, a first mounting frame 313 and a first drive motor 312. The first drive motor 312 is connected to the driving roller 311 through a coupling to drive the driving roller 311 to rotate; the driving roller 311 is mounted on the first mounting frame 313.

[0072] The follower assembly 32 consists of a follower roller 321 and a second mounting frame 323. The follower roller 321 is mounted on the second mounting frame 323. A pre-positioning baffle 322 can be mounted on the side of the second mounting frame 323 or the side of the first mounting frame 313. The pre-positioning baffle 322 is in an arc shape that convexly projects toward the cylinder, helping to guide the cylinder onto the driving roller 311 and the follower roller 321. The follower roller 321 rotates with the rotation of the driving roller 311. Several driving rollers 311 and several follower rollers 321 are arranged along the length (circumference) of the cylinder. The bottom of the cylinder rests on the driving rollers 311 and several follower rollers 321, moving with the rotation of the driving roller 311 and the follower roller 321.

[0073] Further, such as Figure 13 and Figure 15 As shown, the adjustment assembly 33 consists of a third wedge block 331, two fourth wedge blocks 332 adapted to the wedge surface at the bottom of the third wedge block 331, and an adjusting screw 333. The third wedge block 331 is placed on top of the two fourth wedge blocks 332. The wedge surfaces at both ends of the bottom of the third wedge block 331 are inclined from inside to outside and upward. The wedge surface at the top of the fourth wedge block 332 is adapted to the wedge surface at the bottom of the third wedge block 331, so that when the two fourth wedge blocks 332 move relative to each other or move away from each other, the height of the third wedge block 331 can be adjusted.

[0074] Furthermore, the two fourth wedge blocks 332 each have a third threaded hole 3321 formed therein, with the threads of the two third threaded holes 3321 running in opposite directions. The ends of the adjusting screw 333 are threadedly connected to the two third threaded holes 3321, respectively. The adjusting screw 333 passes through the two fourth wedge blocks 332, enabling the two fourth wedge blocks 332 to move toward or away from each other. The two fourth wedge blocks 332 are located at either end of the top of the base 34, respectively. A screw stopper 334 is fixedly provided in the middle of the top of the base 34. The adjusting screw 333 is provided with two second stoppers 3331. The screw section of the adjusting screw 333 located between the two second stoppers 3331 passes through the screw stopper 334, thereby limiting axial movement of the adjusting screw 333. One end of the adjusting screw 333 is connected to the second drive motor, and a pressure sensor is installed on the contact wedge surface between the fourth wedge block 332 and the third wedge block 331. The second drive motor drives the adjusting screw 333 to rotate, which can automatically realize the simultaneous movement of the two fourth wedge blocks 332.

[0075] The working process of the device is described in detail below with reference to the drawings in the embodiments.

[0076] The second drive motor drives the adjusting screw 333 to rotate, and the two fourth wedge blocks 332 move toward the middle (outward) at the same time, and then the third wedge block 331 moves upward (downward) to achieve high (low) adjustment; the active roller 311 is installed on the corresponding third wedge block 331, and the follower roller 321 is installed on the corresponding third wedge block 331. The first drive motor 312 drives the active roller 311 to rotate, and the overall height adjustment and rotation of the active roller 311 and the follower roller 321 can be achieved: the height adjustment ensures that each roller can contact the cylinder, ensures the contact force and can achieve the horizontal adjustment of the cylinder, thereby ensuring the verticality of the longitudinal weld; the rotation can realize the rotation of the cylinder, thereby achieving the position adjustment of the longitudinal seam of the cylinder.

[0077] Adaptive height adjustment method: The second drive motor of the adjusting screw 333 can cooperate with a displacement sensor in the height direction to realize automatic rotation of the second drive motor of the adjusting screw 333; when the target height changes, the second drive motor can automatically rotate to make the active roller 311 or the follower roller 321 reach the target height adaptive adjustment; it can also cooperate with a pressure sensor to realize constant pressure contact force control of the contact surface of the active roller 311 or the follower roller 321: when the pressure sensor is configured, the third wedge 331 can also be set as two parts, and a pressure sensor installation position is added between the two parts. The pressure sensor can receive the pressure signal in the vertical direction;

[0078] A guide mechanism is provided between the third wedge block 331 and the fourth wedge block 332, and vertical constraint can be achieved by relying on the deadweight of the cylinder or the locking screw; a pre-compression spring can also be configured, and the pre-compression spring is installed on the upper plane position of the third wedge block 331, so that the pre-compression spring applies an elastic force to the third wedge block 331, thereby achieving the fit between the third wedge block 331 and the fourth wedge block 332.

[0079] This mechanism can also be rotated 90 degrees and used horizontally to achieve horizontal position adjustment (not used in this working condition).

[0080] A spring mechanism can be added between the third wedge block 331 and the active roller 311 to achieve flexible contact control of the active roller 311: the third wedge block 331 can be set as two parts, and a spring installation position can be added between the two parts. The contact force between the active roller 311 and the cylinder is transmitted by the spring. Since the spring can be extended and compressed, even if there is a small change in the height of the cylinder, it can ensure that the active roller 311 and the cylinder are always in contact, thereby achieving flexible contact control.

[0081] When the present invention is applied to friction stir welding of a cylinder, the position of the weld is adjusted through height adjustment and rotation, so that the longitudinal seam of the cylinder is perpendicular to the horizontal plane.

[0082] The working process of the tool is described in detail below with reference to the drawings in the embodiments.

[0083] Before discharging, the two semicircular hoops 112 are opened synchronously, and the cylinder is placed in the clamp with a sling (rough positioning is performed through the pre-positioning baffle 322 on the follower assembly 32 under the cylinder), and the oil cylinder drives the hoop 11 to hold the cylinder tightly to achieve the initial positioning of the cylinder; the hoop 11 is opened again, and the first drive motor 312 drives the active roller 311 to rotate, thereby driving the cylinder to rotate. When the weld is rotated into place, the weld position detection sensor gives a signal and the cylinder stops rotating; at the same time, the weld position sensor works to detect whether the weld is tilted. When the weld is tilted, the software calculates the height that needs to be adjusted at the adjustment assembly 33 through an algorithm. The adjustment assembly 33 is driven by the motor to realize automatic height adjustment (the adjustment assembly 33 can also be manually adjusted) to adjust the weld to a position perpendicular to the horizontal plane; the hoop 11 is tightened again, and the positioning and clamping of the cylinder are completed;

[0084] The lead-in block 22 and the lead-out block 23 are respectively installed in the first fixing device 24 and the second fixing device 27. After the fixing is completed, welding can be achieved;

[0085] After welding is completed, loosen the lead-in block 22 and the lead-out block 23;

[0086] The hoop 11 opens automatically and the cylinder is taken out; the next working cycle is carried out.

[0087] This fixture can perform longitudinal FSW (friction stir welding) of aluminum cylinders with an outer diameter of φ1935mm, a wall thickness of 52mm, and a height of 760mm. This fixture focuses on structural strength and rigidity, meeting the welding process requirements of a large 52mm weld depth and aluminum parts. (A 52mm weld depth creates significant upsetting and expansion forces during welding.)

[0088] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A friction stir welding tool for a large diameter cylinder, characterized by: The invention comprises an outer embracing positioning device (1) for embracing a cylinder, a mounting mechanism (2) for mounting an introduction block (22) and an outlet block (23), a driving device (3) for supporting the cylinder and driving the cylinder to rotate circumferentially, and a bottom plate (4); the outer embracing positioning device (1), the mounting mechanism (2), and the driving device (3) are all mounted on the bottom plate (4); The outer embracing positioning device (1) comprises an embracing hoop (11) for embracing the cylinder, a first driving assembly (12) for driving the embracing hoop (11) to open and close radially, and a floating pressing assembly for pressing the cylinder; the first driving assembly (12) is distributed on both sides of the open end of the embracing hoop (11), and the open end forms a working gap for the stirring needle to extend into; The mounting mechanism (2) comprises a weld support seat (21), a first fixing device (24) and a second fixing device (27), wherein the first fixing device (24) and the second fixing device (27) are respectively mounted on two ends of the weld support seat (21); the first fixing device (24) comprises an adjusting member (242) for pushing the introduction block (22) toward the weld, and the second fixing device (27) comprises an adjusting assembly (272) for pushing the lead-out block (23) toward the weld, so that the introduction block (22) and the lead-out block (23) can exert force on each other to clamp the cylinder, and at this time, the adjacent ends of the introduction block (22) and the lead-out block (23) are respectively close to the two ends of the weld; The driving device (3) comprises a frame, wherein an inner cavity of the frame forms a working cavity into which a cylinder can be placed so as to limit the height of the cylinder, and a plurality of second driving components (31) for driving the cylinder in the working cavity to generate circumferential rotation and a pre-positioning baffle (322) for limiting the position of the cylinder are arranged in the working cavity; the pre-positioning baffle (322) is arranged in the working cavity and is in an arc shape convex toward the cylinder.

2. The friction stir welding tool for a large diameter cylinder according to claim 1, characterized in that: The hoop (11) is formed by hingedly connecting two semicircular hoop bodies (112), and the non-hinged ends of the two semicircular hoop bodies (112) constitute the open end; the driving source (121) of the first driving component (12) is connected to the outer wall of the hoop (11).

3. The friction stir welding tool for a large diameter cylinder according to claim 1, characterized in that: The adjusting assembly (272) includes a first wedge block (2722) and a second wedge block (2723) with matching wedge surfaces; the first wedge block (2722) is connected to the pushing member (2721) so that the first wedge block (2722) can move perpendicular to the weld; the lead-out block (23) is placed above the second wedge block (2723) in the height direction, and when the pushing member (2721) pushes the first wedge block (2722), the wedge surface cooperates to push the second wedge block (2723) upward, thereby generating a lifting driving action for the lead-out block (23).

4. The friction stir welding tool for a large diameter cylinder according to claim 1, characterized in that: The driving device (3) further comprises a plurality of follower assemblies (32) arranged along the circumference of the cylinder, and a pre-positioning baffle (322) is located on the follower assemblies (32); the bottom of the second driving assembly (31) and the bottom of the follower assembly (32) are both provided with an adjustment assembly (33) for realizing radial height adjustment of the corresponding assembly; the adjustment assembly (33) comprises a third wedge block (331), two fourth wedge blocks (332) adapted to the wedge surface at the bottom of the third wedge block (331), and an adjustment screw (333); the adjustment screw (333) passes through the two fourth wedge blocks (332) and enables the two fourth wedge blocks (332) to move toward or away from each other.

5. The friction stir welding tool for a large diameter cylinder according to claim 1, characterized in that: The first driving component (12) includes a driving source (121) and a mounting bracket (122), the bottom of the mounting bracket (122) is fixedly mounted on the base plate (4), a through hole (1221) is provided on the mounting bracket (122), and the driving source (121) is movably mounted in the through hole (1221), thereby realizing a horizontal swinging movement of the driving source (121); the telescopic end of the driving source (121) extends out of the through hole (1211), and the telescopic end of the driving source (121) is fixedly sleeved with a connecting sleeve (123), the outer wall of the connecting sleeve (123) is hinged to the first hinge seat (124), and a push plate (111) is integrally formed on the outer wall of the open end of the clamp (11), and the first hinge seat (124) and the push plate (111) are detachably connected.

6. The friction stir welding tool for a large diameter cylinder according to claim 2, characterized in that: The floating clamping assembly includes a plurality of clamping strips (131) installed at intervals on the inner wall of the clamping hoop (11), a clamping block (132) located on the inner side of the open ends of the two semicircular hoop bodies (112), and an adjusting screw (133) passing through the ends of the open ends of the two semicircular hoop bodies (112); one end of the adjusting screw (133) located on the inner side of the semicircular hoop body (112) is fixedly connected to the clamping block (132); one end of the adjusting screw (133) located on the outer side of the semicircular hoop body (112) is provided with a preload spring (134); the end face of the clamping block (132) close to the semicircular hoop body (112) is arc-shaped.

7. The friction stir welding tool for a large diameter cylinder according to claim 3, characterized in that: The second fixing device (27) further comprises an adjusting fixing seat (271) fixedly connected to the weld support seat (21); a second groove (2711) is provided on the adjusting fixing seat (271) toward the weld; the first wedge block (2722), the second wedge block (2723) and the lead-out block (23) are sequentially placed in the second groove (2711) along the length direction of the weld; the pushing member (2721) is a rotating screw; the adjusting fixing seat (271) is provided with a screw thread connected to the weld; A vertical first through-hole (275), the rotating screw passes through the first through-hole (275) and is threadedly connected to the first threaded hole (273) on the first wedge block (2722); two first limit blocks (274) for limiting the axial movement of the pushing member (2721) are fixedly provided on the pushing member (2721), and the two first limit blocks (274) are distributed at both ends of the first through-hole (275); the bottom of the weld support seat (21) is fixedly mounted on the base plate (4).

8. The friction stir welding tool for a large diameter cylinder according to claim 3, characterized in that: The first fixing device (24) further comprises a flip body (241) hinged to the weld support seat (21) and a fixing assembly (25) for fixing the flip body (241); the flip body (241) is provided with a first groove (2411) with an opening facing the weld; the introduction block (22) is placed in the first groove (2411); the adjustment member (242) is a first top screw, and the pushing end of the adjustment member (242) is placed in the first groove (2411) and contacts the introduction block (22); the fixing assembly (25) comprises a latch (253), a latch limiting seat (251) for limiting the latch (253), and a latch fixing seat (252); the latch limiting seat (251) is fixed to the flip body (241); the latch fixing seat ( 252) is fixed on the weld support seat (21), the fixed end of the latch (253) passes through the latch limiting seat (251) and is detachably connected to the latch fixing seat (252); a limiting ring (291) is fixedly provided on the latch (253) for limiting the axial movement of the latch (253), and the limiting ring (291) is placed in the latch limiting seat (251); a second through-hole (2511) is passed through the latch limiting seat (251), and a third through-hole (2521) is provided on the latch fixing seat (252), the fixed end of the latch (253) passes through the second through-hole (2511) and is connected to the third through-hole (2521), and the central axis of the third through-hole (2521) is collinear with the central axis of the second through-hole (2511).

9. The friction stir welding tool for a large diameter cylinder according to claim 4, characterized in that: The interiors of the two fourth wedge blocks (332) are both provided with a third threaded hole (3321), and the thread directions of the two third threaded holes (3321) are opposite; the two ends of the adjusting screw (333) are respectively threadedly connected to the two third threaded holes (3321); the driving device (3) also includes a base (34), the bottom of the base (34) is fixedly mounted on the bottom plate (4); a screw limit seat (334) is fixedly provided on the base (34), and the adjusting screw (333) is provided with two screws for limiting the adjustment. The screw (333) generates a second limit block (3331) for axial movement, and the screw section of the adjusting screw (333) is located between the two second limit blocks (3331) and passes through the screw limit seat (334); the wedge surfaces at both ends of the bottom of the third wedge block (331) are both inclined and extend upward from the inside to the outside, and the wedge surface at the top of the fourth wedge block (332) is adapted to the wedge surface at the bottom of the third wedge block (331); a pressure sensor is installed on the contact wedge surface between the fourth wedge block (332) and the third wedge block (331).

10. The friction stir welding tool for a large diameter cylinder according to claim 4, characterized in that: The second driving assembly (31) comprises a driving roller (311) for supporting the cylinder, a first mounting frame (313) for mounting the driving roller (311), and a first driving motor (312) for driving the driving roller (311) to rotate; the following assembly (32) comprises a following roller (321) for supporting the cylinder and a second mounting frame (323) for mounting the following roller (321); the bottom of the first mounting frame (313) and the bottom of the second mounting frame (323) are both fixedly connected to a side of the third wedge block (331) away from the fourth wedge block (332).

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