A safety valve clamping assembly robot with automatic positioning of multi-specification valve bodies

Abstract

This invention relates to the field of valve assembly technology and discloses a safety valve clamping and assembly robot with automatic positioning of multi-specification valve bodies. The robot includes a frame, assembly fixture, a loading platform, and a loading robotic arm. The assembly fixture is equipped with a rotary table capable of indexing rotation, and several positioning modules are arranged circumferentially on the top of the rotary table. Each positioning module includes a fixture table, a rotating plate, and several positioning units with positioning bodies. This invention, by arranging multiple sets of positioning modules circumferentially on the rotary table and relying on the rotating plate to drive the positioning units to slide radially, can adapt to valve bodies of different flange specifications. The loading platform calibration module pre-corrects the valve body's placement posture, and the clamping module mounted on the loading robotic arm uses internal expansion clamping to hold the valve body, while the positioning shaft is inserted into the upper flange bolt holes to achieve circumferential constraint. The transfer process suppresses valve body torsional displacement, and the valve body's coaxiality and angular accuracy are ensured during unloading. Multi-specification valve body positioning and assembly can be completed without changing the fixture.

Description

Technical Field

[0001] This invention relates to the field of valve assembly technology, and specifically to a safety valve clamping and assembly robot with automatic positioning of multi-specification valve bodies. Background Technology

[0002] Safety valves are widely used in pressure systems such as pressure vessels and pressure pipelines for pressure relief protection under overpressure conditions. The valve body, as the assembly base, directly determines the subsequent assembly quality of the safety valve. Existing automated safety valve assembly lines often use rotary indexing tables to achieve multi-station flow of the valve body. A loading robot transports the valve body to the worktable station, and then assembly robots deployed around the perimeter sequentially complete the assembly of components such as the valve disc, spring, and valve cover.

[0003] Existing assembly equipment has shortcomings when assembling safety valve bodies of different specifications: the bottom flange specifications of different valve bodies vary, and traditional workstation tooling is mostly a fixed special positioning structure. One set of tooling can only be used for a single specification of valve body. When switching production models, it is necessary to stop the machine to disassemble and replace the positioning fixture, which is cumbersome and makes it difficult to achieve flexible assembly of multiple specifications of valve bodies.

[0004] During valve body loading, the valve body at the loading station is prone to placement posture deviation; conventional robotic gripper mechanisms mostly only achieve simple clamping and lack circumferential constraints on the valve body. When the valve body is transferred and placed onto the rotary table, coaxiality and circumferential angle are difficult to guarantee, easily leading to flange hole alignment failure and positioning failure, interfering with subsequent assembly. Existing equipment cannot simultaneously achieve pre-calibration of loading posture, circumferential constraints during robotic gripping, and adaptive positioning of valve bodies of multiple specifications on the worktable, which restricts the assembly stability and production efficiency of multiple safety valve models. Summary of the Invention

[0005] To address the aforementioned shortcomings of existing technologies, this invention provides a safety valve clamping and assembly robot with automatic positioning of multiple valve bodies. This effectively solves the problem that traditional workstation fixtures are mostly fixed, dedicated positioning structures, with one set of fixtures only suitable for a single valve body specification. When switching production models, it is necessary to stop the machine to disassemble and replace the positioning fixture, which is cumbersome and makes it difficult to achieve flexible assembly of multiple valve bodies.

[0006] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a safety valve clamping and assembly robot with automatic positioning of multi-specification valve bodies, including a frame, assembly fixture, material handling table and loading robot arm; the assembly fixture is equipped with a rotary table that can be rotated by indexing, and the top of the rotary table is circumferentially arranged with several positioning modules; a single positioning module includes a fixture table, a rotating plate, and several positioning units with positioning bodies. The tooling table is fixed to the top of the rotary table, and the rotary plate is rotatably connected to the inside of the rotary table; several positioning units are slidably assembled in several circumferentially opened sliding slots on the top of the tooling table, and the bottom of several positioning units extends into the inside of the tooling table and is connected to the rotary plate in a transmission manner. The material handling platform is equipped with a calibration module; the calibration module includes a calibration cylinder. The output end of the loading robotic arm is equipped with a positioning clamping module; the clamping module includes an expansion cylinder and a positioning shaft; the loading robotic arm drives the clamping module to move downward, and the expansion cylinder extends into the inner cavity of the valve body from the top opening of the valve body, and clamps and fixes the inner wall of the valve body in a radial expansion manner from the inside to the outside; the positioning shaft is used to insert downward into the flange bolt hole of the valve body to apply circumferential rotation constraint to the valve body.

[0007] Furthermore, the rotating plate has several circumferentially arranged inclined grooves inside, and the bottom of the positioning body of several positioning units is integrally formed with guide protrusions, and the guide protrusions at the bottom of several positioning bodies are movably inserted into the corresponding inclined grooves. Each positioning module also includes a hollow rotating shaft; the hollow rotating shaft is rotatably connected to the inside of the rotary table, and the top end of the hollow rotating shaft extends into the tooling table and is fixed to the rotating plate.

[0008] Furthermore, a drive gear is fixed to the bottom end of the hollow rotating shaft; an annular gear sleeve and an adjusting motor are provided at the bottom of the rotating table; the annular gear sleeve is rotatably connected to the bottom of the rotating table and meshes with the drive gears in all the positioning modules; the adjusting motor is fixed to the bottom of the rotating table and is fixed to the hollow rotating shaft in one of the positioning modules.

[0009] Furthermore, the bottom of the positioning body is integrally formed with a positioning part, which is a stepped rotating body structure, consisting of multiple coaxial cylinders with progressively increasing diameters stacked from top to bottom, with the end faces of each cylinder sharing a common central axis.

[0010] Furthermore, the positioning part has a stepped rotating body with a rotating cavity inside, and several abutting blocks are radially slidably connected inside the rotating cavity. The sides of the several abutting blocks are integrally formed with multiple sets of abutting protrusions, and the multiple sets of abutting protrusions on the sides of the abutting blocks extend through the through openings on the outer surface of the positioning part. Several abutting blocks are provided with wedge-shaped parts on their other sides, and the positioning part is slidably connected to the wedge-shaped drive part in an up-and-down sliding manner. The drive slope of the wedge-shaped drive part is connected to the slope of all the wedge plates in a wedge-shaped transmission.

[0011] Furthermore, the positioning unit also includes an eccentric column and a drive cylinder; the eccentric column is rotatably connected to the top of the rotating plate via a rotating shaft, the positioning body is a frame structure and is movably sleeved on the outer surface of the eccentric column, and the bottom of the wedge-shaped drive part extends into the interior of the frame and contacts the outer surface of the eccentric column. In several positioning units, the rotating shaft ends of the eccentric columns all extend into the hollow rotating shaft and are rotatably connected to the hollow rotating shaft through bearings. The ends of the rotating shafts extending into the hollow rotating shaft are integrally formed with force-bearing protrusions. The driving cylinder is fixed inside the hollow rotating shaft, and the driving end of the driving cylinder is fixed with several protruding rods.

[0012] Furthermore, the clamping module also includes a clamping body that is connected to the output end of the loading robot arm, and a connecting body is connected to the bottom of the clamping body; there are multiple tension cylinders, which are fixed to the outer surface of the connecting body in an equidistant ring, and each tension cylinder has a tensioning part fixed to its tensioning end; There are at least two positioning shafts, which are arranged in a equidistant, surrounding manner; the positioning shafts are driven up and down by positioning cylinders and are used to insert into the bolt holes of the flange on the valve body to rotate and constrain the valve body.

[0013] Furthermore, the clamping body has two symmetrical radial grooves inside, and each radial groove is provided with a sliding block and an adjusting screw. The positioning cylinder is fixedly connected to the sliding block, and the telescopic end of the cylinder is fixed to the positioning shaft. The bottom end of the positioning shaft is constricted. The sliding block is slidably connected inside the radial groove, and the adjusting screw is threadedly connected to the clamping body and its end is drivenly connected to the sliding block. It is used to drive the sliding block to adjust radially by rotating the adjusting screw, thereby adjusting the position of the positioning shaft and the positioning cylinder.

[0014] Furthermore, the top of the tooling table is integrally formed with a positioning sleeve, and the bottom end of the connecting body is integrally formed with a rod-shaped positioning head; The connecting body is a rotating structure, and the top of the connecting body is rotatably connected to the bottom of the clamping body through a bearing; a piezoelectric actuator is installed inside the clamping body, and the actuation output end of the piezoelectric actuator abuts against the upper surface of the connecting body.

[0015] Furthermore, the material handling platform is a long strip-shaped trough component, which is fixed to the machine frame via a mounting bracket; the calibration cylinder is fixed to the end of the material handling platform and is arranged along the width direction of the material handling platform; the telescopic end of the calibration cylinder is rotatably connected to two symmetrical rollers via a connecting frame. A calibration plate is fixedly connected to the material handling platform. The calibration plate and the calibration cylinder are symmetrically arranged, and the discharge flange in the valve body placed on the material handling platform faces the calibration surface of the calibration plate. A calibration shaft is fixed on the material handling platform along its length.

[0016] The technical solution provided by this invention has the following advantages compared with the prior art: 1. This invention, by arranging multiple positioning modules circumferentially on a rotary table, relies on a rotating plate to drive the positioning units to slide radially, thus adapting to valve bodies of different flange specifications. The loading platform calibration module pre-corrects the valve body's placement posture, and the clamping module mounted on the loading robotic arm uses internal expansion to clamp the valve body. Simultaneously, the positioning shaft is inserted into the upper flange bolt holes to achieve circumferential constraint. The transfer process suppresses valve body torsional displacement, and the unloading ensures the valve body's coaxiality and angular accuracy. Multi-specification valve body positioning and assembly can be completed without changing fixtures, reducing downtime and production changeover time, and improving the stability and production efficiency of safety valve assembly.

[0017] 2. The positioning unit of this invention adopts a stepped rotating positioning part, which adapts to flange bolt holes of various diameters by using stepped sections of different diameters. An eccentric column drives a wedge-shaped driving part, pushing the clamping block outward to clamp the inner wall of the bolt hole, eliminating the assembly gap between the positioning pin and the bolt hole, and preventing movement during valve body assembly. A single drive cylinder can drive all eccentric columns of the same positioning module to move synchronously, achieving multi-point synchronous locking. There is no need to replace the positioning pin components, it is compatible with bolt hole positioning of different specifications, reduces spare parts, ensures reliable locking, and improves the positioning accuracy of the valve body.

[0018] 3. The material handling platform of this invention is equipped with a calibration cylinder, rollers, a calibration plate, and a calibration shaft. During valve body transport, the calibration shaft performs initial positioning to prevent large-angle deflection of the valve body. The calibration cylinder drives the rollers to push the valve body, pressing the valve body discharge flange tightly against the reference surface of the calibration plate, completing the pre-calibration of the valve body posture. The rollers can rotate freely, avoiding pushing and scratching the surface of the valve body casting. This structure is not dependent on the external contour of the valve body, is universal for multiple valve body specifications, reduces the difficulty of robotic arm grasping and alignment, reduces subsequent positioning and alignment failures, and improves the success rate of equipment changeover assembly. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. 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 structure of the present invention; Figure 2 This is a front view of the structure of the present invention; Figure 3 This is a schematic diagram of the material handling platform of the present invention; Figure 4 This is a cross-sectional view of the clamping module of the present invention; Figure 5This is a schematic diagram of the assembly tooling of the present invention; Figure 6 This is a bottom view of the rotating platform of the present invention; Figure 7 This is a cross-sectional view of the positioning module of the present invention; Figure 8 For the present invention Figure 7 A magnified view of a section at point A in the middle; Figure 9 This is a schematic diagram of the transmission of the rotating plate and multiple positioning units of the present invention.

[0021] The labels in the diagram represent: 10. Machine frame; 11. Assembly fixture; 12. Loading table; 13. Loading robot arm; 14. Rotary table; 20. Positioning module; 21. Tooling table; 22. Rotary plate; 23. Hollow rotating shaft; 24. Drive gear; 25. Annular gear sleeve; 26. Adjustment motor; 27. Positioning unit; 271. Positioning body; 272. Positioning part; 273. Clamping block; 274. Wedge-shaped drive part; 275. Eccentric column; 276. Drive cylinder; 278. Protruding rod; 30. Calibration module; 31. Calibration cylinder; 32. Roller; 33. Calibration plate; 34. Calibration shaft; 40. Clamping module; 41. Expansion cylinder; 42. Positioning shaft; 43. Clamping body; 44. Connecting body; 45. Positioning cylinder; 46. Sliding block; 47. Adjusting screw; 48. Positioning sleeve; 49. Piezoelectric actuator. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0023] The present invention will be further described below with reference to embodiments. Example

[0024] Please see Figures 1 to 9This invention provides a technical solution: a safety valve clamping and assembly robot with automatic positioning of multiple valve bodies. The whole machine takes the frame platform 10 as the supporting base. The frame platform 10 integrates three core units: assembly fixture 11, material placement platform 12, and material loading robotic arm 13. This solves the industry pain points of traditional safety valve assembly robots that can only adapt to a single valve body specification, require disassembly and assembly of fixtures when changing production, are prone to circumferential deflection during valve body transfer, and fail to align flange bolt holes.

[0025] Assembly fixture 11 serves as the base for valve body assembly station, and is equipped with a rotary table 14 capable of intermittent indexing and rotation, multiple sets of assembly robot mounting seats, and drive motors. The drive motors output torque to drive the rotary table 14 to achieve indexing and rotation, and sequentially transfer the valve body to each of the loading, assembly, and unloading stations. The mounting seats are used to fix the assembly robots and complete the assembly of components such as valve discs, springs, and valve covers.

[0026] Multiple positioning modules 20 are evenly arranged circumferentially on the top surface of the rotary table 14. Each positioning module 20 consists of a tooling table 21, a rotating plate 22, and multiple positioning units 27. The tooling table 21 is rigidly fixed on the top surface of the rotary table 14. The rotating plate 22 is slewingly supported and assembled in the internal cavity of the rotary table 14. The positioning unit 27 serves as the positioning actuator for the bottom inlet flange of the valve body and can be inserted into the bolt holes of the bottom inlet flange of the valve body to achieve circumferential and radial positioning constraints of the valve body on the tooling table 21. Multiple positioning units 27 are slidably assembled in the circumferential grooves opened on the top surface of the tooling table 21. The lower end of the positioning unit 27 extends downward into the internal cavity of the tooling table 21 and forms a mechanical transmission coupling with the rotating plate 22. Relying on the rotational movement of the rotating plate 22, all positioning units 27 are driven to synchronously generate radial advance and retreat displacement, changing the circumferential diameter of the distribution circle of the positioning units 27, thereby adapting to the bottom inlet flanges of valve bodies with different outer diameters and different bolt hole distribution circle diameters, and realizing self-adaptive positioning of valve bodies of multiple specifications without replacement parts.

[0027] The loading platform 12 is equipped with an experience calibration module 30. The core actuator of the calibration module 30 is a calibration cylinder 31, which performs pre-calibration of the placement posture and flange reference surface of the safety valve body to be grasped on the loading platform 12, eliminating the angle and position deviation caused by the random placement of the valve body before loading, and reducing the difficulty of subsequent robotic arm grasping and alignment.

[0028] The end of the loading robotic arm 13 is equipped with a positioning clamping module 40, which picks up and transfers the pre-calibrated safety valve body from the loading table 12 to the positioning module 20 of the assembly fixture 11, completing the valve body's positioning and placement for subsequent assembly by the robotic arm. The clamping module 40 includes a tensioning cylinder 41 and a positioning shaft 42. The loading robotic arm 13 moves the clamping module 40 downward, and the tensioning cylinder 41 extends into the inner cavity of the valve body through the top opening, using a radial tensioning method from the inside out to clamp and fix the inner wall of the valve body. The positioning shaft 42 can be inserted downward into the bolt hole of the upper flange of the valve body to apply circumferential rotation constraint to the valve body, suppressing torsional displacement of the valve body during the robotic arm's transfer and ensuring the stability of the angular reference throughout the transfer process.

[0029] See attached document Figure 9 Multiple inclined grooves are formed circumferentially inside the rotating plate 22. The bottom of the positioning body 271 of each positioning unit 27 is integrally formed with a guide protrusion, which slides into the corresponding inclined groove to form an inclined sliding transmission pair. When the rotating plate 22 rotates, the groove wall of the inclined groove applies a lateral component force to the guide protrusion, converting the circumferential rotation of the rotating plate 22 into the radial linear displacement of the positioning body 271 along the groove opening of the tooling table 21. When the rotating plate 22 rotates clockwise, all positioning units 27 expand radially outward simultaneously. When the rotating plate 22 rotates counterclockwise, all positioning units 27 contract radially inward simultaneously, thereby changing the positioning pitch circle diameter formed by multiple sets of positioning units 27 to adapt to valve bodies with different flange bolt hole distribution circle sizes, realizing hole insertion positioning of valve bodies of various specifications.

[0030] The single positioning module 20 is also equipped with a hollow rotating shaft 23; the hollow rotating shaft 23 is slewing bearing assembled inside the rotary table 14, and the top end of the hollow rotating shaft 23 extends upward into the inner cavity of the tooling table 21 and is rigidly connected to the rotating plate 22. See attached document Figure 6 The bottom end of the hollow rotating shaft 23 extends outward from the bottom surface of the rotary table 14, and a drive gear 24 is fixedly mounted on the shaft end. A large gear ring-shaped annular sleeve 25 is rotatably mounted on the bottom of the rotary table 14, and the annular sleeve 25 meshes with the drive gears 24 of all positioning modules 20. An adjusting motor 26 is fixedly mounted on the bottom of the rotary table 14, and the output shaft of the adjusting motor 26 is rigidly connected to the hollow rotating shaft 23 of one set of positioning modules 20.

[0031] Working principle: The output torque of the adjustable motor 26 drives the hollow shaft 23 to rotate, which in turn drives the drive gear 24 to rotate. The drive gear 24 drives the annular gear sleeve 25 to rotate circumferentially. The annular gear sleeve 25, through gear meshing, synchronously drives the corresponding drive gears 24 and hollow shafts 23 of all other positioning modules 20 to rotate synchronously. This achieves synchronous rotation of the rotating plates 22 of all workstation positioning modules 20 on the rotary table 14, and synchronous radial expansion / contraction of all workstation positioning units 27. This shared annular gear sleeve 25 synchronous transmission scheme uses only a single adjustable motor 26 to achieve synchronous specification switching of all workstation positioning mechanisms, ensuring that the pitch circle dimensions of each workstation are completely consistent, avoiding synchronization deviations caused by independent drives of multiple motors, simplifying the electrical control system, and improving changeover efficiency.

[0032] See attached document Figures 7 to 9 The lower end of the positioning body 271 is integrally formed with a positioning part 272. The positioning part 272 adopts a multi-level coaxial stepped rotating body structure, which is composed of multiple cylinders with progressively larger diameters stacked from top to bottom, with each level of cylinder maintaining the same central axis.

[0033] The bolt hole diameters of the bottom inlet flanges of safety valves of different specifications vary significantly. The multi-stage stepped rotating positioning part 272 has a diameter that gradually increases from top to bottom. After the positioning unit 27 moves radially into place, the positioning part 272 inserts downward into the flange bolt hole. When the hole diameter is small, the upper small-diameter stepped section enters the hole; when the hole diameter is large, the lower large-diameter stepped section can enter the hole. By relying on the fit between the outer circle of the stepped column and the inner wall of the bolt hole, the insertion and positioning of bolt holes of different diameters can be achieved without replacing the positioning pin components, realizing cross-specification compatible positioning of hole diameters and reducing the number of tooling parts.

[0034] See attached document Figure 8 The positioning part 272 has a stepped rotating cavity inside, and multiple sets of slidable clamping blocks 273 are radially assembled inside the rotating cavity. Each clamping block 273 has multiple sets of clamping protrusions on its side. The side wall of the positioning part 272 has a corresponding through-hole, and the clamping protrusions can extend outward from the through-hole. A spring assembly is arranged inside the rotating cavity. The spring assembly normally applies a radial inward reset force to the clamping block 273. When the clamping operation is removed, the spring assembly pulls the clamping block 273 inward to retract, and the clamping protrusions retract into the rotating cavity, eliminating the squeezing interference with the outer wall and facilitating the smooth removal of the positioning part 272 from the bolt hole.

[0035] Each clamping block 273 has a wedge-shaped inclined surface (wedge-shaped part) on its inner side; a wedge-shaped driving part 274 is vertically slidably assembled in the inner cavity of the positioning part 272, and the driving inclined surface on the outer periphery of the wedge-shaped driving part 274 and the wedge-shaped part of each clamping block 273 fit together to form a wedge-shaped transmission pair. When the wedge-shaped driving part 274 moves upward axially, the wedge-shaped inclined surface generates a radial component force, pushing all the clamping blocks 273 to slide outward radially, and clamping the protrusion extending outward from the through-hole to press the inner wall of the bolt hole; relying on multi-point radial extrusion, the positioning part 272 is locked inside the flange bolt hole, eliminating the assembly gap between the positioning pin and the bolt hole, and suppressing the slight movement during the valve body processing; when the valve body needs to be released after assembly, the wedge-shaped driving part 274 returns downward, and the spring assembly pulls the clamping block 273 back, releasing the hole wall clamping lock.

[0036] See attached document Figure 5 , Figure 7 and Figure 9 The positioning unit 27 further includes an eccentric column 275 and a drive cylinder 276; the eccentric column 275 is rotatably mounted on the top surface of the rotating plate 22 via a rotating shaft; the positioning body 271 is a frame-type base, and the frame is movably fitted on the outer cylindrical surface of the eccentric column 275; the lower end of the wedge-shaped drive part 274 extends downward into the frame of the positioning body 271, and the bottom surface contacts the outer cylindrical surface of the eccentric column 275.

[0037] Motion principle: The eccentric column 275 rotates around its own rotation axis, and the eccentricity of the eccentric cylindrical surface is converted into axial lifting displacement, which pushes the wedge-shaped drive part 274 upward, thereby triggering the radial outward pressing action of the clamping block 273 to complete the locking of the inner wall of the bolt hole.

[0038] The ends of the rotating shafts corresponding to the eccentric columns 275 of all positioning units 27 extend into the hollow cavity of the hollow rotating shaft 23, and are rotated and supported by bearings. The ends of the rotating shafts extending into the inner cavity have integrally formed force-bearing protrusions, which are perpendicular to the axis of the rotating shaft. Under normal conditions without external driving force, the force-bearing protrusions maintain a horizontal posture. A drive cylinder 276 is fixedly arranged inside the hollow cavity of the hollow rotating shaft 23, and multiple protruding rods 278 are fixed to the output end of the drive cylinder 276.

[0039] The drive cylinder 276 extends and lifts, causing multiple protruding rods 278 to move upwards synchronously. The protruding rods 278 press the force-bearing protrusions at the ends of each rotating shaft, causing the force-bearing protrusions to rotate angularly, which in turn causes all the eccentric columns 275 to rotate synchronously in the same direction. Relying on a single set of built-in drive cylinders 276, all positioning units 27 inside the same positioning module 20 can synchronously perform the clamping and locking action. The drive cylinder 276 retracts, the eccentric column 275 rotates back to its original position, the wedge-shaped drive part 274 falls, and the clamping block 273 retracts and unlocks under the action of the spring group.

[0040] See attached documentFigure 2 and Figure 4 The clamping module 40 includes a clamping body 43, the upper end of which is rigidly connected to the end of the feeding robot arm 13 via a transmission mechanism; the lower end of the clamping body 43 is connected to a rotary connecting body 44; multiple tension cylinders 41 are fixed to the outer surface of the connecting body 44 in an equidistant manner, and tensioning parts are assembled on the outer end of the piston rod of the tension cylinder 41.

[0041] The loading robotic arm 13 drives the clamping module 40 to move downward as a whole, and the connecting body 44 extends into the inner cavity of the valve body from the top opening of the safety valve body; multiple sets of expansion cylinders 41 extend synchronously, and each expansion part squeezes the inner wall of the valve body radially outward to achieve inner wall expansion clamping from the inside out; unlike external gripper clamping, internal expansion clamping will not interfere with the outer contour of the valve body flange, adapts to irregularly shaped cast valve bodies, and the clamping force is uniform, avoiding damage and deformation of the outer wall of the valve body.

[0042] At least two positioning shafts 42 are distributed at equal angles in the circumference. The positioning shafts 42 are driven by the positioning cylinder 45 to make vertical extension and retraction movements. After the valve body is tightened and clamped, the positioning cylinder 45 drives the positioning shafts 42 to extend downward and insert into the bolt holes of the upper flange of the valve body, applying circumferential constraints to the valve body to prevent circumferential torsion of the valve body during the high-speed transfer process of the robot arm, and ensuring the stability of the angular reference of the valve body flange.

[0043] See attached document Figure 4 The clamping body 43 has two sets of symmetrically arranged radial grooves inside, and the sliding block 46 and adjusting screw 47 are assembled inside the grooves. The positioning cylinder 45 is fixedly installed on the sliding block 46, and the telescopic end of the positioning cylinder 45 is connected downward to the positioning shaft 42. The lower end of the positioning shaft 42 is machined into a constricted guide structure. The conical guide can reduce the alignment resistance of the inserted flange bolt hole, and at the same time, it is compatible with various upper flange bolt holes of different diameters.

[0044] The adjusting screw 47 and the clamping body 43 form a threaded transmission pair, and the end of the screw is connected to the sliding block 46. Rotating the adjusting screw 47 can push the sliding block 46 to generate radial displacement inside the radial groove, and simultaneously change the distribution pitch circle diameter of the positioning cylinder 45 and the positioning shaft 42. For different specifications of valve body flange bolt holes with different distribution circle diameters, the position of the positioning shaft 42 can be changed by manually adjusting the screw 47, so as to achieve circumferential locking adaptation of flanges of multiple specifications of valve body without replacing the clamping components.

[0045] Example 2: The difference from Example 1 is that; See attached document Figure 4 and Figure 5The top surface of the tooling table 21 is integrally formed with a positioning sleeve 48; the bottom end of the connecting body 44 is machined into a rod-shaped positioning head; when the clamping module 40 grabs the valve body and lowers it to the work position of the tooling table 21, the rod-shaped positioning head is inserted into the positioning sleeve 48, and the clamping module 40 and the tooling table 21 are coaxially aligned by means of a pin sleeve, which indirectly ensures that the axis of the clamped safety valve body and the tooling table 21 coincides, providing a coaxial reference for the subsequent insertion of the bottom positioning unit 27 into the flange bolt hole.

[0046] The connecting body 44 is a rotating component, and its upper end is rotatably connected to the bottom surface of the clamping body 43 via a bearing. After the expansion cylinder 41 completes the internal expansion of the valve body, the valve body and the connecting body 44 have circumferential rotational freedom. The positioning cylinder 45 drives the positioning shaft 42 to insert downward into the flange bolt hole on the valve body. If there is a slight angular deviation in the valve body, the axial clamping force when the positioning shaft 42 is inserted will push the valve body and the connecting body 44 to make a slight rotation, automatically completing the circumferential angle reset and alignment of the valve body.

[0047] A piezoelectric actuator 49 is installed inside the cavity of the clamping body 43. The actuation output end of the piezoelectric actuator 49 abuts against the upper end face of the connecting body 44. After the valve body angle is aligned, the piezoelectric actuator 49 is energized to generate a micron-level elongation, pressing down on the upper end face of the connecting body 44. The connecting body 44 is locked and fixed by the friction of the bearing end face, eliminating the degree of rotational freedom. This ensures that the valve body will not rotate circumferentially again during the entire process of falling down onto the tooling table 21, ensuring that the bottom inlet flange bolt hole of the valve body is accurately aligned with the positioning unit 27, and avoiding damage to the positioning pin.

[0048] Example 3: The difference from Example 1 is that; See attached document Figure 3 The loading platform 12 is a long slotted component, fixed to the machine frame 10 by a mounting bracket; multiple safety valve bodies to be processed are arranged sequentially along the length of the loading platform 12. The calibration cylinder 31 is horizontally fixed at the end of the loading platform 12, and the telescopic end of the cylinder is hinged to two sets of symmetrically arranged rollers 32 through a connecting frame; the rollers 32 can rotate freely, reducing the risk of friction and scratches on the valve body surface during the pushing process.

[0049] A calibration plate 33 is fixed to the side of the loading platform 12, and the calibration plate 33 and the calibration cylinder 31 are arranged opposite each other. When the valve body is placed on the loading platform 12, the discharge flange plane of the valve body faces the calibration reference plane of the calibration plate 33. The calibration cylinder 31 extends and drives two rollers 32 to push the outer circle of the valve body forward, pressing the valve body against the calibration plate 33, so that the plane of the valve body discharge flange is completely in contact with the reference plane of the calibration plate 33. The valve body placement posture is calibrated by relying on the flange plane as a unified angle reference. This reference positioning method does not depend on the valve body outline and is compatible with valve bodies of different specifications. It greatly reduces the difficulty of subsequent robotic arm clamping and tooling positioning module 20 alignment, and improves the assembly success rate of the whole set of equipment during production changeover.

[0050] The loading platform 12 is also fixed with a calibration shaft 34 along its length. During the feeding and conveying process, the valve body discharge flange edge is initially constrained by the calibration shaft 34 to prevent the valve body from deflecting too much at an angle on the loading platform 12. This avoids excessive angular deviation of the valve body, which would prevent the subsequent calibration cylinder 31 and calibration plate 33 from completing attitude correction and ensures that the valve body can enter the effective calibration stroke range.

[0051] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A safety valve clamping and assembly robot with automatic positioning of multi-specification valve bodies, comprising a frame (10), an assembly fixture (11), a loading table (12), and a loading robotic arm (13); the assembly fixture (11) is equipped with a rotary table (14) capable of indexing and rotating, characterized in that: The top of the rotary table (14) is circumferentially arranged with several positioning modules (20); each positioning module (20) includes a tooling table (21), a rotating plate (22), and several positioning units (27) with positioning bodies (271). The tooling table (21) is fixed to the top of the rotary table (14), and the rotating plate (22) is rotatably connected to the inside of the rotary table (14); a number of positioning units (27) are slidably assembled in a number of circumferentially opened sliding slots on the top of the tooling table (21), and the bottom of the number of positioning units (27) extends into the inside of the tooling table (21) and is connected to the rotating plate (22) in a transmission manner. The loading platform (12) is equipped with a calibration module (30); the calibration module (30) includes a calibration cylinder (31); The output end of the loading robotic arm (13) is equipped with a positioning clamping module (40); the clamping module (40) includes a tensioning cylinder (41) and a positioning shaft (42); the loading robotic arm (13) drives the clamping module (40) to move down, and the tensioning cylinder (41) extends into the inner cavity of the valve body from the top opening of the valve body, and clamps and fixes the inner wall of the valve body in a radial tensioning manner from the inside to the outside; the positioning shaft (42) is used to insert downward into the flange bolt hole of the valve body to apply circumferential rotation constraint to the valve body.

2. The safety valve clamping and assembly robot with automatic positioning of multi-specification valve bodies according to claim 1, characterized in that: The rotating plate (22) has several circumferentially arranged inclined grooves inside. The bottom of the positioning body (271) of several positioning units (27) is integrally formed with guide protrusions, and the guide protrusions at the bottom of several positioning bodies (271) are movably inserted into the corresponding inclined grooves. The single positioning module (20) also includes a hollow rotating shaft (23); the hollow rotating shaft (23) is rotatably connected to the inside of the rotary table (14), and the top of the hollow rotating shaft (23) extends into the inside of the tooling table (21) and is fixed to the rotating plate (22).

3. The safety valve clamping and assembly robot with automatic positioning of multi-specification valve bodies according to claim 2, characterized in that: The bottom end of the hollow rotating shaft (23) is fixed with a drive gear (24); the bottom of the rotating table (14) is provided with an annular gear sleeve (25) and an adjusting motor (26); the annular gear sleeve (25) is rotatably connected to the bottom of the rotating table (14) and meshes with the drive gears (24) in all the positioning modules (20); the adjusting motor (26) is fixed to the bottom of the rotating table (14) and is fixed to the hollow rotating shaft (23) in one of the positioning modules (20).

4. The safety valve clamping and assembly robot with automatic positioning of multi-specification valve bodies according to claim 2, characterized in that: The bottom of the positioning body (271) is integrally formed with a positioning part (272). The positioning part (272) is a stepped rotating body structure, which is composed of multiple coaxial cylinders with successively increasing diameters stacked from top to bottom, with the end faces of each cylinder sharing a common central axis.

5. A safety valve clamping and assembly robot with automatic positioning of multi-specification valve bodies according to claim 4, characterized in that: The positioning part (272) has a stepped rotating body with a rotating cavity inside, and a number of abutting blocks (273) are radially slidably connected inside the rotating cavity. The sides of the abutting blocks (273) are integrally formed with multiple sets of abutting protrusions, and the multiple sets of abutting protrusions on the sides of the abutting blocks (273) extend through the through opening on the outer surface of the positioning part (272). Several abutting blocks (273) are provided with wedge-shaped parts on their other side, and the positioning part (272) is slidably connected to the wedge-shaped drive part (274) in an up-and-down sliding manner. The drive slope of the wedge-shaped drive part (274) is driven by the slope of all the wedge plates in a wedge-shaped transmission.

6. A safety valve clamping and assembly robot with automatic positioning of multi-specification valve bodies according to claim 5, characterized in that: The positioning unit (27) also includes an eccentric column (275) and a drive cylinder (276); the eccentric column (275) is rotatably connected to the top of the rotating plate (22) via a rotating shaft, the positioning body (271) is a frame structure and is movably sleeved on the outer surface of the eccentric column (275), and the bottom of the wedge-shaped drive part (274) extends into the frame and contacts the outer surface of the eccentric column (275); The rotating shaft ends of the eccentric column (275) in several positioning units (27) all extend into the hollow rotating shaft (23) and are rotatably connected to the hollow rotating shaft (23) through bearings. The end of the rotating shaft extending into the hollow rotating shaft (23) is integrally formed with a force-bearing protrusion. The driving cylinder (276) is fixed inside the hollow rotating shaft (23), and the driving end of the driving cylinder (276) is fixed with several protruding rods (278).

7. A safety valve clamping and assembly robot with automatic positioning of multi-specification valve bodies according to claim 1, characterized in that: The clamping module (40) also includes a clamping body (43) that is connected to the output end of the loading robot arm (13) for transmission. The bottom of the clamping body (43) is connected to a connecting body (44). There are multiple expansion cylinders (41), which are fixed to the outer surface of the connecting body (44) in an equidistant ring manner. The expansion ends of the multiple expansion cylinders (41) are all fixed with expansion parts. There are at least two positioning shafts (42), which are arranged in an equidistant ring. The positioning shafts (42) are driven up and down by positioning cylinders (45) and are used to insert into the bolt holes of the upper flange of the valve body to rotate and constrain the valve body.

8. A safety valve clamping and assembly robot with automatic positioning of multi-specification valve bodies according to claim 7, characterized in that: The clamping body (43) has two symmetrical radial grooves inside. Each of the two radial grooves is provided with a sliding block (46) and an adjusting screw (47). The positioning cylinder (45) is fixedly connected to the sliding block (46), and the telescopic end of the cylinder is fixed to the positioning shaft (42). The bottom end of the positioning shaft (42) is constricted. The sliding block (46) is slidably connected inside the radial groove, and the adjusting screw (47) is threadedly connected to the clamping body (43) and its end is connected to the sliding block (46) for transmission. It is used to drive the sliding block (46) to adjust radially by rotating the adjusting screw (47), thereby adjusting the position of the positioning shaft (42) and the positioning cylinder (45).

9. A safety valve clamping and assembly robot with automatic positioning of multi-specification valve bodies according to claim 8, characterized in that: The top of the tooling table (21) is integrally formed with a positioning sleeve (48), and the bottom of the connecting body (44) is integrally formed with a rod-shaped positioning head. The connecting body (44) is a rotating structure, and the top of the connecting body (44) is rotatably connected to the bottom of the clamping body (43) through a bearing; a piezoelectric actuator (49) is installed inside the clamping body (43), and the actuation output end of the piezoelectric actuator (49) abuts against the upper surface of the connecting body (44).

10. A safety valve clamping and assembly robot with automatic positioning of multi-specification valve bodies according to claim 1, characterized in that: The material handling platform (12) is a long strip-shaped trough component, which is fixed to the machine frame (10) by a mounting bracket; the calibration cylinder (31) is fixed at the end of the material handling platform (12) and is arranged along the width direction of the material handling platform (12); the telescopic end of the calibration cylinder (31) is rotatably connected to two symmetrical rollers (32) through a connecting frame. A calibration plate (33) is fixedly connected to the material handling platform (12). The calibration plate (33) and the calibration cylinder (31) are symmetrically arranged, and the discharge flange in the valve body placed on the material handling platform (12) faces the calibration surface of the calibration plate (33). A calibration shaft (34) is fixed along the length direction on the material handling platform (12).

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