A flexible jaw for fitting to a valve of various specifications

Abstract

The application discloses a kind of occlusion type flexible hand claw of adapting multiple specifications valve, it is related to valve sand casting production technical field, including installation base, fixed centering clamp jaw and adjustable centering clamp jaw;Fixed centering clamp jaw is fixedly connected to installation base by reference support, and forms fixed clamping reference;Adjustable centering clamp jaw is located in the side of fixed centering clamp jaw and is connected to installation base by displacement adjusting mechanism, and forms adjustable clamping end;Displacement adjusting mechanism can adjust the relative position between adjustable centering clamp jaw and fixed centering clamp jaw, so that they can be commonly clamped different specifications valve workpiece.The application adopts fixed centering clamp jaw and adjustable centering clamp jaw asymmetric collaborative clamping architecture, and single clamping reference is formed in fixed end, which eliminates the multi-reference superposition cumulative positioning error;Adjustable end realizes independent position adjustment by displacement adjusting mechanism, and can be adapted to multiple series regulating valve, ball valve sand casting blank gripping and positioning clamping, effectively improves the flexible and automated production level of production line.

Description

Technical Field

[0001] This invention relates to the field of valve sand casting production technology, and in particular to a biting flexible gripper that is adaptable to valves of various specifications. Background Technology

[0002] In the valve sand casting production process, gating and riser cutting is a critical finishing process after valve body forming. Currently, the industry mostly adopts a production mode of manual gripping and clamping, fixed tooling positioning, or simple robotic grippers to assist in the operation. Valve sand casting blanks generally have problems such as large dimensional deviations, uneven valve body end faces, and asymmetrical main and auxiliary valve body structures. Traditional clamping tooling has a simple structure and poor adaptability, and can only clamp valve bodies of a single specification. It cannot compensate for the dimensional errors caused by the sand casting process. During operation, clamping deviation, uneven force, and workpiece slippage are very likely to occur, which not only affect the accuracy of gating and riser cutting, but also easily cause damage to the valve body workpiece.

[0003] Existing robotic grippers mostly employ a bilaterally symmetrical adjustable structure. This type of structure suffers from multiple superimposed positioning errors, resulting in low centering accuracy and making it difficult to meet the demands of high-precision cutting operations. Furthermore, conventional clamping structures lack unilateral height compensation capabilities, making them unsuitable for clamping and fixing asymmetrical ball valves and other irregularly shaped valve bodies. Their tooling versatility is extremely poor, requiring complete fixture replacement during production line changes, which is time-consuming and costly, severely hindering flexible production. In addition, traditional pneumatic clamping structures lack comprehensive operational condition monitoring functions, making them prone to clamping failures under high-temperature cutting conditions, posing safety hazards such as workpiece falls and equipment damage.

[0004] Therefore, there is an urgent need for a clamping device that can accommodate multiple specifications, provide high-precision centering, ensure high-temperature reliability, and enable rapid model changeover, in order to meet the actual needs of automated and flexible production in sand casting valve production lines. Summary of the Invention

[0005] In view of this, the present invention proposes a bite-type flexible gripper that is adaptable to valves of various specifications, aiming to solve at least one of the above-mentioned technical problems.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] This invention provides a bite-type flexible gripper adaptable to valves of various specifications, comprising: Mounting base; The clamping execution unit includes a fixed centering jaw and an adjustable centering jaw. The fixed centering jaw is fixedly connected to the mounting base via a reference support to form a fixed clamping reference. The adjustable centering jaw is located to the side of the fixed centering jaw and is connected to the mounting base via a displacement adjustment mechanism to form an adjustable clamping end. The displacement adjustment mechanism can adjust the relative position between the adjustable centering jaw and the fixed centering jaw so that the fixed centering jaw and the adjustable centering jaw can jointly clamp valve workpieces of different specifications.

[0008] This invention employs an asymmetrical collaborative clamping structure consisting of a fixed centering jaw and an adjustable centering jaw. The fixed centering jaw is fixed to the mounting base via a reference support, forming a single fixed clamping reference. The adjustable centering jaw achieves relative position adjustment through a displacement adjustment mechanism. Compared to traditional double-sided symmetrical adjustable structures, the single fixed reference avoids the cumulative positioning error caused by the superposition of multiple references, ensuring the basic accuracy of centering clamping. Simultaneously, the displacement adjustment mechanism can adjust the jaw spacing according to the length and flange spacing of valves of different specifications. One set of tooling can adapt to multiple types of valves, improving the flexibility of production lines.

[0009] As a further improvement to the above technical solution, a floating compensation device is connected in series between the adjustable centering gripper and the displacement adjustment mechanism, which is used to passively adapt to the posture deviation of the valve body end face and buffer the clamping impact during the clamping process.

[0010] The beneficial effects of the above technical solution are as follows: by connecting a floating compensation device in series between the adjustable centering gripper and the displacement adjustment mechanism, the gripper can passively adapt to the actual posture of the valve body end face during the process of contacting and clamping the valve body, thereby compensating for the tilt deviation and parallelism error of the sand casting blank end face, ensuring that the working surface of the gripper is completely in contact with the clamping surface of the valve body, and avoiding localized stress concentration; at the same time, it can absorb the small error of robot positioning, buffer the rigid impact at the moment of clamping, and protect the surface of the valve body casting and the vise transmission structure.

[0011] As a further improvement to the above technical solution, the top end of the reference support is fixed to the bottom surface of the mounting base, and the fixing and centering clamp is fixedly installed at the bottom end of the reference support. The displacement adjustment mechanism includes a lateral adjustment component and a longitudinal adjustment component. The lateral adjustment component is installed on the bottom surface of the mounting base and located on the side of the reference support. The longitudinal adjustment component is installed on the moving end of the lateral adjustment component. The top end of the floating compensation device is fixed to the moving end of the longitudinal adjustment component. The adjustable centering gripper is installed on the bottom end of the floating compensation device. The lateral adjustment component is used to drive the adjustable centering jaw to move closer to or further away from the fixed centering jaw in a direction parallel to the bottom surface of the mounting base; the longitudinal adjustment component is used to drive the adjustable centering jaw to reciprocate in a direction perpendicular to the bottom surface of the mounting base.

[0012] The beneficial effects of the above technical solution are as follows: by connecting the lateral adjustment component, the longitudinal adjustment component, the floating compensation device, and the adjustable centering gripper in series, a complete transmission chain from the mounting base to the adjustable centering gripper is formed. The lateral adjustment component drives the adjustable centering gripper to move closer to or further away from the fixed centering gripper in a direction parallel to the bottom surface of the mounting base, which can accommodate valves of different lengths; the longitudinal adjustment component drives the adjustable centering gripper to move up and down in a direction perpendicular to the bottom surface of the mounting base, which can compensate for the height difference between the end faces of the main and auxiliary valve bodies of the ball valve and the height deviation of the casting end faces caused by the sand casting process, thus solving the problem that asymmetrical valve bodies cannot be synchronously clamped horizontally.

[0013] As a further improvement to the above technical solution, the floating compensation device includes a top flange, a floating compensation module and a bottom flange connected in sequence. The top flange is fixedly connected to the moving end of the longitudinal adjustment component, and the bottom flange is fixedly connected to the fixed end of the adjustable centering gripper.

[0014] The beneficial effects of the above technical solution are as follows: By defining the specific structure through the sequential connection of the top flange, the floating compensation module, and the bottom flange, the modular assembly method of the floating compensation device is clearly defined. The top flange is fixedly connected to the moving end of the longitudinal adjustment component, and the bottom flange is fixedly connected to the fixed end of the adjustable centering jaw. This ensures that the lifting and lowering movement of the longitudinal adjustment component is reliably transmitted to the adjustable centering jaw. At the same time, the floating compensation module plays a passive compensation and buffering role when subjected to clamping force, ensuring that the clamping working surface and the valve body clamping surface are completely in contact to improve clamping stability and protect the surface of the valve body casting.

[0015] As a further improvement to the above technical solution, the floating compensation module is an elastic body.

[0016] The beneficial effects of the above technical solution are: the floating compensation module uses an elastomer material, making the floating compensation device simple in structure and reliable in response. During the clamping process, the elastomer undergoes recoverable elastic deformation under stress, realizing passive compensation and impact buffering for end face posture deviation; after clamping is completed, the elastomer automatically returns to its initial shape, without affecting the accuracy and effect of the next clamping.

[0017] As a further improvement to the above technical solution, the lateral adjustment component is a servo slide; the reference support is located on one side of the sliding direction of the moving end of the servo slide.

[0018] The beneficial effects of the above technical solution are as follows: using a servo slide as a lateral adjustment component can achieve high-precision stepless continuous position adjustment. With the help of PLC control signals, the slide can be precisely driven to move to the target position, ensuring that the distance adjustment between the adjustable centering gripper and the fixed centering gripper is accurate and reliable. The reference support is located on one side of the sliding direction of the servo slide, ensuring that the relative positional relationship between the fixed clamping reference and the adjustable clamping end is clear during the lateral adjustment process.

[0019] As a further improvement to the above technical solution, the longitudinal adjustment component includes a fixed support, a servo cylinder, and a guide structure; the top end of the fixed support is fixed to the moving end of the transverse adjustment component, the servo cylinder is mounted on the fixed support, and its output end can reciprocate in a direction perpendicular to the bottom surface of the mounting base; the top end of the floating compensation device is fixed to the output end of the servo cylinder. The guiding structure includes a guide column flange and guide columns symmetrically arranged on both sides of the servo cylinder. The guide column flange is fixedly connected to the fixed support. One end of the guide column is fixedly connected to the output end of the servo cylinder, and the other end of the guide column passes through the guide column flange and slides with the guide column flange.

[0020] The beneficial effects of the above technical solution are: the output end of the servo electric cylinder directly drives the floating compensation device and the adjustable centering gripper to move vertically; the guide columns symmetrically arranged on both sides of the servo electric cylinder form a double-sided symmetrical guide and limit structure, which can counteract the radial sway torque generated during the extension and retraction of the servo electric cylinder, ensuring that the adjustable centering gripper moves vertically without tilting or shaking throughout the entire process of extension, retraction or lifting, and achieving high-precision height compensation adjustment.

[0021] As a further improvement to the above technical solution, the reference support includes a tubular support top flange, a tubular support connector, and a tubular support bottom flange; the tubular support top flange, the tubular support connector, and the tubular support bottom flange are coaxially and fixedly connected in sequence; the top surface of the tubular support top flange is fixed to the bottom surface of the mounting base, and the fixed end of the fixing and centering claw is connected to the bottom surface of the tubular support bottom flange.

[0022] The beneficial effects of the above technical solution are: the reference support adopts a three-segment rigid connection structure, so that the fixed centering jaws form an immovable and unique fixed clamping reference. This segmented pipe support structure has high load-bearing strength and good assembly coaxiality, which can effectively avoid the cumulative positioning error caused by the superposition of multiple references in the traditional double-sided adjustable structure, and ensure the basic accuracy of valve centering and clamping.

[0023] As a further improvement to the above technical solution, it also includes a quick-change adapter plate disposed on the top surface of the mounting base, which is used to cooperate with the zero-point positioning mother plate pre-installed at the end of the industrial robot to form a quick-change module.

[0024] The beneficial effects of the above technical solution are: by setting up a quick-change adapter plate, the flexible gripper tooling and the robot end effector can be quickly docked and detached without the need for manual disassembly and assembly of fasteners; combined with micron-level repeatability positioning accuracy, it supports the rapid switching of multiple grippers of different clamping specifications at the robot end effector, greatly shortening the production line changeover downtime and adapting to the turnover needs of flexible casting production lines for multiple types of valves.

[0025] As a further improvement to the above technical solution, both the fixed centering jaw and the adjustable centering jaw include a self-centering vise and a clamping jaw detachably mounted on the jaws of the self-centering vise; the clamping surface of the clamping jaw is provided with teeth.

[0026] The beneficial effects of the above technical solution are as follows: both the fixed centering jaws and the adjustable centering jaws adopt a self-centering vise, which automatically centers the workpiece during the clamping process, ensuring clamping accuracy; the clamping jaws can be detachably installed on the jaws of the self-centering vise, and the corresponding clamping jaws can be quickly replaced according to different valve body end face specifications; the teeth set on the clamping surface can be embedded into the rough and uneven surface of the sand casting blank, which greatly improves the static friction of clamping, prevents the valve body from slipping and shifting during gripping and cutting, and ensures clamping reliability and operational safety.

[0027] As can be seen from the above technical solutions, compared with the prior art, the interlocking flexible gripper that adapts to valves of multiple specifications disclosed in this invention has the following advantages and beneficial effects.

[0028] 1. Excellent clamping and centering accuracy. It adopts an asymmetrical collaborative clamping structure with fixed and adjustable centering jaws. The fixed centering jaws form a single fixed clamping reference through a reference support, eliminating the cumulative positioning error caused by multiple references. The adjustable centering jaws achieve independent dual-axis adjustment through a displacement adjustment mechanism, and, in conjunction with a floating compensation device, passively adapt to the dimensional deviations and end-face parallelism errors of the sand-cast blanks, ensuring the centering and clamping accuracy of valve castings and improving the consistency of gating and riser cutting.

[0029] 2. Wide range of workpiece adaptability. The interlocking gripping jaws can embed into the rough surface of sand casting to increase the static friction of gripping. The teeth can be blunted to avoid scratching the sealing reference surface of the valve body flange. It is equipped with three gripping modes: double jaw synchronous centering mode, double jaw differential compensation mode, and single jaw independent gripping mode, which can cover different diameter control valves and ball valve blanks. Small workpieces can be stably gripped by a single jaw on one side. One set of tooling can replace multiple sets of special fixtures, significantly improving versatility.

[0030] 3. Safe and reliable in high-temperature conditions. Based on the standard pneumatic self-centering vise, it has been optimized for high-temperature resistance, with the addition of heat insulation coating and high-temperature resistant seals, making it suitable for high-temperature operation environments such as flame cutting. Relying on the original air cut-off self-locking function, combined with multi-dimensional working condition sensor monitoring, abnormal working conditions will automatically alarm and lock the action, effectively avoiding the risk of workpiece slippage and falling, and ensuring the safety of automated operation.

[0031] 4. Excellent flexible production changeover efficiency. The system integrates a zero-point quick-change docking system and modular replaceable grippers, supporting robots to automatically complete the overall tooling switchover and gripper replacement without manual disassembly and assembly of pipelines and fasteners. This significantly reduces production line downtime for changeovers and is suitable for the flexible production needs of sand-cast valves with multiple varieties and small batches.

[0032] 5. Easy production line integration. The entire gripper can use a standardized pneumatic and electrical integration interface, and the drive and sensor signals can be directly connected to the production line PLC control system. It can be matched with the existing automated casting production line without additional modifications, with low deployment cost, strong adaptability, and can quickly realize unmanned operation of valve cutting process. Attached Figure Description

[0033] 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 embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0034] Figure 1 This is a three-dimensional schematic diagram of the overall structure of a bite-type flexible gripper that is adapted to valves of various specifications according to the present invention.

[0035] Figure 2 This is a three-dimensional schematic diagram from another perspective of the overall structure of the interlocking flexible gripper that adapts to valves of various specifications according to the present invention.

[0036] Figure 3 This is a schematic diagram of the adjustable centering gripper and floating compensation device of a bite-type flexible gripper adapted to valves of various specifications according to the present invention.

[0037] Figure 4 This is a schematic diagram of the gripping claw structure of a bite-type flexible gripper that is adapted to valves of various specifications according to the present invention.

[0038] Figure 5 This is a schematic diagram of the structure of a bite-type flexible gripper that is adapted to hold valves of various specifications according to the present invention.

[0039] Figure 6 This is a schematic diagram of a valve structure applicable to a bite-type flexible gripper that is adapted to multiple valve specifications according to the present invention.

[0040] In the diagram: 1. Mounting base; 11. Lifting ring; 2. Fixed centering jaws; 3. Adjustable centering jaws; 31. Self-centering vise; 311. Lubrication interface; 312. Air source interface; 32. Clamping jaws; 321. Jaws; 322. Quick-release bolt mounting slot; 323. Mounting reference surface; 4. Reference support; 41. Top flange of tubular support; 42. Tubular support connector; 43. Bottom flange of tubular support; 5. Displacement adjustment mechanism; 51. Lateral adjustment assembly; 511. Lateral slide rail; 512. Lateral slide rail 513. Ball screw; 514. Lateral servo motor; 515. Lateral servo slide connecting flange; 52. Longitudinal adjustment assembly; 521. Fixed support; 522. Servo electric cylinder; 523. Guide column; 524. Guide column flange; 525. Servo electric cylinder bottom flange; 6. Floating compensation device; 61. Top flange; 62. Floating compensation module; 63. Bottom flange; 7. Quick-change adapter plate; 8. Valve; 81. Sand casting riser; 82. Flange sealing reference surface; 83. Valve clamping end face. Detailed Implementation

[0041] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0042] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0043] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0044] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0045] According to embodiments of the present invention, such as Figures 1 to 5 As shown, a flexible gripper adapted to valves of various specifications includes: a mounting base 1 and a clamping actuation unit.

[0046] The clamping unit includes a fixed centering jaw 2 and an adjustable centering jaw 3. The fixed centering jaw 2 is fixedly connected to the mounting base 1 via a reference support 4 to form a fixed clamping reference. The adjustable centering jaw 3 is located to the side of the fixed centering jaw 2 and is connected to the mounting base 1 via a displacement adjustment mechanism 5 to form an adjustable clamping end. The displacement adjustment mechanism 5 can adjust the relative position between the adjustable centering jaw 3 and the fixed centering jaw 2 so that the fixed centering jaw 2 and the adjustable centering jaw 3 can jointly clamp valve workpieces of different specifications.

[0047] This embodiment employs an asymmetrical collaborative clamping structure consisting of a fixed centering gripper 2 and an adjustable centering gripper 3. The fixed centering gripper 2 is fixed to the mounting base 1 via a reference support 4, forming a single fixed clamping reference. The adjustable centering gripper 3 achieves relative position adjustment via a displacement adjustment mechanism 5. Compared to the traditional double-sided symmetrical adjustable structure, the single fixed reference avoids the cumulative positioning error caused by the superposition of multiple references, ensuring the basic accuracy of centering clamping. At the same time, the displacement adjustment mechanism 5 can adjust the gripper spacing according to the length and flange spacing of valves of different specifications. One set of tooling can be adapted to multiple types of valves, improving the flexibility of production line production.

[0048] In some embodiments, a floating compensation device 6 is connected in series between the adjustable centering gripper 3 and the displacement adjustment mechanism 5, which is used to passively adapt to the posture deviation of the valve body end face and buffer the clamping impact during the clamping process.

[0049] By connecting a floating compensation device 6 in series between the adjustable centering gripper 3 and the displacement adjustment mechanism 5, the gripper can passively adapt to the actual posture of the valve body end face during the process of contacting and clamping the valve body. This compensates for the tilt deviation and parallelism error of the sand casting blank end face, ensuring that the working surface of the gripper is completely in contact with the clamping surface of the valve body, and avoiding localized stress concentration. At the same time, it can absorb the small errors of robot positioning, buffer the rigid impact at the moment of clamping, and protect the surface of the valve body casting and the vise transmission structure.

[0050] In some embodiments, the top end of the reference support 4 is fixed to the bottom surface of the mounting base 1, and the fixing and centering claw 2 is fixedly installed on the bottom end of the reference support 4.

[0051] The displacement adjustment mechanism 5 includes a lateral adjustment component 51 and a longitudinal adjustment component 52. The lateral adjustment component 51 is installed on the bottom surface of the mounting base 1 and located on the side of the reference support 4. The longitudinal adjustment component 52 is installed on the moving end of the lateral adjustment component 51. The top of the floating compensation device 6 is fixed to the moving end of the longitudinal adjustment component 52. The adjustable centering gripper 3 is installed on the bottom of the floating compensation device 6.

[0052] The lateral adjustment component 51 is used to drive the adjustable centering jaw 3 to move closer to or further away from the fixed centering jaw 2 in a direction parallel to the bottom surface of the mounting base 1; the longitudinal adjustment component 52 is used to drive the adjustable centering jaw 3 to reciprocate in a direction perpendicular to the bottom surface of the mounting base 1.

[0053] By connecting the lateral adjustment component 51, the longitudinal adjustment component 52, the floating compensation device 6, and the adjustable centering gripper 3 in series, a complete transmission chain from the mounting base 1 to the adjustable centering gripper 3 is formed. The lateral adjustment component 51 drives the adjustable centering gripper 3 to move closer to or further away from the fixed centering gripper 2 in a direction parallel to the bottom surface of the mounting base 1, which can accommodate valves of different lengths. The longitudinal adjustment component 52 drives the adjustable centering gripper 3 to move up and down in a direction perpendicular to the bottom surface of the mounting base 1, which can compensate for the height difference between the end faces of the main and auxiliary valve bodies of the ball valve and the height deviation of the casting end faces caused by the sand casting process, thus solving the problem that asymmetrical valve bodies cannot be synchronously clamped horizontally.

[0054] In some embodiments, the floating compensation device 6 includes a top flange 61, a floating compensation module 62, and a bottom flange 63 connected in sequence. The top flange 61 is fixedly connected to the moving end of the longitudinal adjustment component 52, and the bottom flange 63 is fixedly connected to the fixed end of the adjustable centering gripper 3.

[0055] The modular assembly method of the floating compensation device 6 is clearly defined by the specific structure of the top flange 61, the floating compensation module 62, and the bottom flange 63 connected in sequence. The top flange 61 is fixedly connected to the moving end of the longitudinal adjustment component 52, and the bottom flange 63 is fixedly connected to the fixed end of the adjustable centering gripper 3. This ensures that the lifting and lowering movement of the longitudinal adjustment component 52 is reliably transmitted to the adjustable centering gripper 3. At the same time, the floating compensation module 62 plays a passive compensation and buffering role when clamping force is applied, so that the clamping working surface and the valve body clamping surface are completely in contact to improve clamping stability and protect the surface of the valve body casting.

[0056] In some embodiments, the floating compensation module 62 is an elastic body.

[0057] The floating compensation module 62 is made of an elastomer, making the floating compensation device 6 simple in structure and reliable in response. During the clamping process, the elastomer undergoes recoverable elastic deformation under stress, realizing passive compensation and impact buffering for end face posture deviation; after clamping is completed, the elastomer automatically returns to its initial shape, without affecting the accuracy and effect of the next clamping.

[0058] Specifically, the floating compensation module 62 can adopt a flexible floating compensation structure in the prior art. It can integrate flexible elastic elements or flexible hinge structures internally, enabling it to generate recoverable micro-displacement and angular deflection after being subjected to force, thus achieving passive posture adaptation and impact buffering. In this embodiment, the floating compensation module 62 is not used alone as a general floating element, but rather forms a composite clamping structure of "active adjustment + passive floating compensation" with the lateral adjustment component 51, the longitudinal adjustment component 52, and the fixed centering gripper 2. This combination addresses the unique characteristics of sand-cast valve blanks, such as poor end-face machining consistency, end-face tilting and parallelism errors caused by sand casting, large dimensional variations in different valve specifications, and clamping impact and off-center loading during the cutting process. It achieves a highly reliable clamping solution combining active position adjustment and passive posture adaptation. The specific working mechanism is as follows: When the longitudinal adjustment component 52 drives the adjustable centering gripper 3 to approach the valve body in a direction perpendicular to the bottom surface of the mounting base 1, if there is tilting or height deviation on the valve body end face, the lateral force and deflection torque generated during the clamping contact process act on the floating compensation module 62. The flexible structure inside the floating compensation module 62 then undergoes a slight elastic deformation, allowing the adjustable centering gripper 3 connected at the bottom to adjust its posture within a certain range relative to the upper mounting end. This ensures that the working surface of the gripper 32 is fully in contact with the valve body's gripping end face, avoiding localized stress concentration caused by uneven end faces or uneven gripping force. Once clamping is complete or the external force is released, the floating compensation module 62 returns to its initial shape based on its own elastic recovery capability, ensuring the accuracy and effectiveness of the next clamping operation.

[0059] Specifically, considering the typical error sources and impact load characteristics of sand-cast valve clamping conditions, the compensation range of the floating compensation module 62 is preferably set as follows: axial and radial floating displacement of 0.5 mm to 5 mm, angle compensation range of ±1° to ±5°, and restoring force range of 50 N to 2000 N. This parameter range can effectively cover the actual working conditions such as valve body end face height error, end face tilt error, small robot positioning deviation, and instantaneous impact load during clamping. While ensuring reliable fit, it avoids excessive deformation affecting clamping stiffness, thereby significantly improving the stability and safety of clamping complex valve body blanks.

[0060] In some embodiments, the lateral adjustment component 51 is a servo slide; the reference support 4 is located on one side of the sliding direction of the moving end of the servo slide.

[0061] Using a servo slide as the lateral adjustment component 51, high-precision stepless continuous position adjustment can be achieved. With the help of PLC control signals, the slide can be precisely driven to move to the target position, ensuring that the distance adjustment between the adjustable centering gripper 3 and the fixed centering gripper 2 is accurate and reliable. The reference support 4 is located on one side of the sliding direction of the servo slide, ensuring that the relative positional relationship between the fixed clamping reference and the adjustable clamping end is clear during the lateral adjustment process.

[0062] Specifically, the lateral adjustment assembly 51 is installed on the right side of the bottom surface of the mounting base 1, allowing for stepless continuous adjustment of the horizontal distance between the adjustable centering jaw 3 and the fixed centering jaw 2 to accommodate sand-cast control valves and ball valve blanks of different lengths and flange spacings. The lateral adjustment assembly 51 is a servo slide, fixedly mounted on the bottom surface of the mounting base 1 via a lateral servo slide connecting flange 515. The lateral adjustment assembly 51 integrates core transmission components such as a lateral slide rail 511, a lateral slider 512, a ball screw 513, and a lateral servo motor 514. The lateral servo slide connecting flange 515 is fixed to the bottom surface of the mounting base 1. Two parallel lateral slide rails 511 are fixed to the lateral servo slide connecting flange 515 along the length of the mounting base 1. The lateral slider 512 is slidably engaged with the lateral slide rails 511, ensuring the straightness of the horizontal reciprocating motion. The ball screw 513 is arranged parallel between the two lateral slide rails 511, and the screw nut pair is rigidly connected to the lateral slider 512. The horizontal servo motor 514 receives a PLC control signal and drives the ball screw 513 to rotate, which is converted into a horizontal reciprocating linear motion of the horizontal slider 512 along the length of the horizontal slide rail 511. The moving end of the horizontal adjustment component 51, namely the horizontal slider 512, serves as the mounting carrier for the vertical adjustment component 52, transmitting the horizontal adjustment power to the adjustable centering gripper 3, thereby achieving precise adjustment of the horizontal position of the adjustable centering gripper 3.

[0063] In some embodiments, the longitudinal adjustment component 52 includes a fixed support 521, a servo cylinder 522, and a guide structure; the top end of the fixed support 521 is fixed to the moving end of the transverse adjustment component 51, the servo cylinder 522 is mounted on the fixed support 521, and its output end can reciprocate in a direction perpendicular to the bottom surface of the mounting base 1; the top end of the floating compensation device 6 is fixed to the output end of the servo cylinder 522.

[0064] The guide structure includes a guide column flange 524 and guide columns 523 symmetrically arranged on both sides of the servo cylinder 522. The guide column flange 524 is fixedly connected to the fixed support 521. One end of the guide column 523 is fixedly connected to the output end of the servo cylinder 522, and the other end of the guide column 523 passes through the guide column flange 524 and slides with the guide column flange 524.

[0065] The output of the servo cylinder 522 directly drives the floating compensation device 6 and the adjustable centering gripper 3 to move vertically. The guide posts 523 symmetrically arranged on both sides of the servo cylinder 522 form a double-sided symmetrical guide and limit structure, which can counteract the radial sway torque generated during the extension and retraction of the servo cylinder 522, ensuring that the adjustable centering gripper 3 is tilted and shaken without tilting or shaking during the vertical extension, retraction or lifting process, and realizing high-precision height compensation adjustment.

[0066] In some embodiments, the longitudinal adjustment assembly 52 further includes a servo cylinder bottom flange 525; the servo cylinder bottom flange 525 is coaxially fixed to the output end of the servo cylinder 522. One end of each of the guide posts 523 on both sides of the servo cylinder 522 is perpendicularly fixed to the servo cylinder bottom flange 525. The servo cylinder bottom flange 525 is coaxially fixed to the top flange 61.

[0067] Specifically, the servo cylinder 522 is movably installed through the guide column flange 524, and linear bearings are provided on both sides of the guide column flange 524 corresponding to the servo cylinder 522; the other ends of the guide columns 523 on both sides of the servo cylinder 522 slide through the linear bearings to form a sliding clearance fit, thus forming a double-sided symmetrical guide and limit structure.

[0068] In some embodiments, the reference support 4 includes a tubular support top flange 41, a tubular support connector 42, and a tubular support bottom flange 43; the tubular support top flange 41, the tubular support connector 42, and the tubular support bottom flange 43 are sequentially coaxially connected and fixed by bolts or welding to form an integral structure; the top surface of the tubular support top flange 41 is fixed to the bottom surface of the mounting base 1, and the fixing end of the fixing centering claw 2 is connected to the bottom surface of the tubular support bottom flange 43.

[0069] The reference support 4 adopts a three-segment rigid connection structure, which makes the fixed centering jaw 2 form a unique fixed clamping reference that cannot be moved. This segmented pipe support structure has high load-bearing strength and good assembly coaxiality. It can effectively avoid the cumulative positioning error caused by the superposition of multiple references in the traditional double-sided adjustable structure, and ensure the basic accuracy of valve centering and clamping.

[0070] Specifically, the top flange 41 of the tubular support is completely fitted and fixed to the left side of the lower surface of the mounting base 1 by countersunk bolts, and the bottom flange 43 of the tubular support is directly and rigidly connected to the top surface of the fixed centering claw 2 by bolts. The entire left-side clamping mechanism has only a single reference, which can effectively avoid the cumulative positioning error caused by the superposition of multiple references in the traditional double-sided adjustable structure, and ensure the basic accuracy of valve centering and clamping.

[0071] In some embodiments, a quick-change adapter plate 7 is provided on the top surface of the mounting base 1 for use in conjunction with the zero-point positioning mother plate pre-installed at the end of the industrial robot to form a quick-change module.

[0072] By setting up a quick-change adapter plate 7, the flexible gripper tooling can be quickly docked and detached from the robot end effector without the need for manual disassembly and assembly of fasteners. With micron-level repeatability positioning accuracy, it supports the rapid switching of multiple grippers of different specifications at the robot end effector, greatly reducing production line changeover downtime and adapting to the turnover needs of flexible casting production lines for various valves.

[0073] Specifically, the quick-change module features a built-in pneumatic locking and unlocking mechanism. Simply introduce compressed air to lock or release the tooling without manual disassembly of fasteners. It boasts micron-level repeatability and supports rapid switching between multiple gripper sizes on the robot's end effector. The quick-change adapter panel integrates a centralized pneumatic and electrical interface. After tooling docking, it automatically establishes pneumatic and electrical connections, eliminating the need for manual cable and pipe connections. This significantly reduces production line downtime during changeovers and adapts to the workflow requirements of flexible casting production lines for various valve products.

[0074] In some embodiments, both the fixed centering jaw 2 and the adjustable centering jaw 3 include a self-centering vise 31 and a clamping jaw 32 detachably mounted on the jaws of the self-centering vise 31; the clamping surface of the clamping jaw 32 is provided with teeth 321.

[0075] Both the fixed centering jaw 2 and the adjustable centering jaw 3 adopt a self-centering vise 31, which automatically centers the workpiece during clamping to ensure clamping accuracy. The clamping jaw 32 can be detachably installed in the jaws of the self-centering vise 31, and the corresponding clamping jaw can be quickly replaced according to different valve body end face specifications. The teeth 321 set on the clamping surface can be embedded into the rough and uneven surface of the sand casting blank, which greatly improves the static friction of clamping, prevents the valve body from slipping and shifting during gripping and cutting, and ensures clamping reliability and operation safety.

[0076] Specifically, both the fixed centering jaw 2 and the adjustable centering jaw 3 use a self-centering vise 31 as the clamping actuator. Their structures are identical, and both can be pneumatic self-centering vises. The self-centering vise 31 located below the reference support 4 forms the fixed reference clamping end, while the self-centering vise 31 located below the floating compensation device 6 forms the compensable movable clamping end. The self-centering vise 31 is driven by standard compressed air and has an internal double-screw symmetrical synchronous transmission structure. During clamping, the workpiece is automatically centered, and it has a self-locking function to maintain pressure even in the event of an air supply interruption, preventing the workpiece from loosening.

[0077] Specifically, for high-temperature cutting conditions in sand casting, the self-centering vise 31 has a high-temperature resistant heat-insulating coating on its outer surface, and its internal seals are made of high-temperature resistant materials, capable of withstanding short-term high-temperature exposure during flame cutting. Exposed air lines are wrapped with a heat-insulating protective layer to ensure structural reliability under high-temperature conditions. The self-centering vise 31 is also equipped with jaw opening and closing sensors, clamping pressure sensors, and workpiece position sensors to monitor the clamping status in real time. All sensor signals are connected to the PLC control system to achieve closed-loop monitoring of the entire clamping process. In case of abnormal conditions such as empty clamping, incomplete clamping, or insufficient air pressure, the system automatically alarms and locks the robot's gripping action. The side wall of the self-centering vise 31 has a standardized lubrication interface 311 and an air source interface 312, which can be used to periodically add grease to maintain the transmission screw. The air line can be quickly connected to the centralized air supply pipeline of the production line.

[0078] Specifically, the gripping claw 32 is detachably mounted on the jaws of the self-centering vise 31, with its top surface serving as the mounting reference surface 323, which fits and positions itself in a close fit with the bottom surface of the jaws. The top surface of the gripping claw 32 has a quick-release bolt mounting groove 322, allowing for tool-free quick assembly and disassembly, and enabling rapid replacement of the corresponding gripping claw according to different valve body end face specifications. The gripping surface of the gripping claw 32 is integrally machined with densely packed teeth 321, the tooth tips of which are rounded and blunted. This allows it to embed into the rough and uneven surface of the sand-cast blank, significantly improving the static friction force during gripping and preventing the valve body from slipping or shifting during gripping and cutting. Simultaneously, the rounded corner structure prevents scratching the valve body flange sealing reference surface. For small-sized ball valve workpieces, the gripping claw 32 features internally thickened stress ribs for optimized load distribution, maintaining stable gripping even with only one jaw of the vise, thus expanding the lower limit of tooling compatibility.

[0079] Specifically, the bottom flange 525 of the servo electric cylinder is a rectangular flange; the top flange 61 is a round flange; the bottom flange 525 is smaller than the top flange 61 and is fixed to the center of the top surface of the top flange 61. The bottom flange 63 is a square flange that is adapted to the top surface of the self-centering vise 31 of the adjustable centering jaw 3.

[0080] In some embodiments, the mounting base 1 is a fixed base plate. As the core bearing body of the gripper, the mounting base 1 is integrally formed from high-strength ductile iron that has undergone stress-relief and aging treatment. It has high rigidity, excellent heat deformation resistance, and can withstand short-term high-temperature radiation from flame cutting stations. It is not prone to deformation during long-term use, ensuring long-term stability of clamping and positioning accuracy.

[0081] Specifically, lifting rings 11 are symmetrically arranged at both ends of the top surface of the mounting base 1 along the length direction for the overall hoisting, transportation, maintenance, and disassembly of the tooling.

[0082] Specifically, the top surface of the mounting base 1 has a positioning mounting position in the center for fixing the quick-change adapter panel 7, and also has a reserved mounting groove for integrated pneumatic and electrical interfaces and a pipeline routing channel. The quick-change adapter panel 7 is rigidly locked to the center of the top surface of the mounting base 1 by high-strength bolts. The bottom surface of the mounting base 1 is divided into two independent mounting areas, left and right. The left area is used for rigid assembly of the reference support 4, and the right area serves as the mounting reference surface for the lateral adjustment component 51.

[0083] Specifically, Figure 6 The structure of valve 8, which is applicable to the flexible gripper of the present invention, is shown. Valve 8 is a DN150 sand-cast regulating valve. Figure 5 The diagram illustrates the state in which the flexible gripper of the present invention holds the valve 8. The sand casting riser 81 is the part that needs to be cut and removed; the two gripping claws 32 installed in the jaws of the self-centering vise 31 can be aligned one-to-one with the flange sealing reference surface 82 and the valve gripping end face 83 of the valve 8 to clamp it.

[0084] In some embodiments, the gripper control method presets three working modes: dual-grip synchronous centering mode, dual-grip differential compensation mode, and single-grip independent gripping mode.

[0085] For standard regulating valves with flat end faces, a double-jaw synchronous centering mode is adopted. The lateral adjustment component 51 drives the adjustable centering jaw 3 to move to a position symmetrical with the fixed centering jaw 2, and the self-centering vises 31 on both sides clamp synchronously to achieve automatic centering of the workpiece.

[0086] For irregularly shaped valve bodies such as ball valves with end face height differences, a double-jaw differential compensation mode is adopted. The lateral adjustment component 51 drives the adjustable centering jaw 3 to move in a direction parallel to the bottom surface of the mounting base 1, coarsely adjusting it to a horizontal position matching the length of the valve body; the longitudinal adjustment component 52 drives the adjustable centering jaw 3 to rise and fall in a direction perpendicular to the bottom surface of the mounting base 1, finely adjusting it to a vertical position corresponding to the height of the valve body end face; the self-centering vises 31 on both sides clamp, and the floating compensation device 6 passively adapts to the tilt deviation of the valve body end face during the clamping process, so that the working surface of the clamping jaw 32 is completely in contact with the valve body clamping surface.

[0087] For small-sized ball valve workpieces, a single-jaw independent clamping mode is adopted. Only one side of the self-centering vise 31 is activated for clamping, and the thickened force ribs inside the clamping jaws 32 ensure even load distribution and maintain stable gripping.

[0088] During the control process, the lateral adjustment component 51 and the longitudinal adjustment component 52 first adjust the adjustable centering gripper 3 to the target position, and then the self-centering vise 31 performs the clamping action, achieving precise matching between the clamping position and the action rhythm. The jaw opening / closing position sensor, clamping pressure sensor, and workpiece position sensor monitor the clamping status in real time. If abnormal conditions such as empty clamping, incomplete clamping, or insufficient air pressure occur, the system automatically alarms and locks the robot's gripping action. The entire control process is integrated into the production line's PLC control system via an integrated interface, enabling automated operation in conjunction with the industrial robot.

[0089] The gripper adopts a modular, layered layout, integrating from top to bottom a quick-change adapter plate 7, mounting base 1, lateral adjustment component 51, longitudinal adjustment component 52, floating compensation device 6, self-centering vise 31, and clamping jaws 32. All functional units are rigidly connected in series, providing quick changeover, multi-dimensional position compensation, passive floating self-adaptation, centering clamping, and full-process condition monitoring. All servo drives, pneumatic clamping, and sensor signals can be connected to the production line PLC control system via an integrated interface, enabling unmanned automated gripping operations in conjunction with industrial robots. The entire system is primarily used in the gating and riser cutting process of valve sand casting production, and can be adapted for automated gripping and positioning of sand casting blanks for various series of control valves and ball valves.

[0090] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0091] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A flexible, interlocking gripper adaptable to valves of various specifications, characterized in that, include: Mounting base (1); The clamping execution unit includes a fixed centering jaw (2) and an adjustable centering jaw (3); the fixed centering jaw (2) is fixedly connected to the mounting base (1) through a reference support (4) to form a fixed clamping reference; the adjustable centering jaw (3) is located to the side of the fixed centering jaw (2) and is connected to the mounting base (1) through a displacement adjustment mechanism (5) to form an adjustable clamping end; the displacement adjustment mechanism (5) can adjust the relative position between the adjustable centering jaw (3) and the fixed centering jaw (2) so that the fixed centering jaw (2) and the adjustable centering jaw (3) can jointly clamp valve workpieces of different specifications.

2. The interlocking flexible gripper adapted to multi-specification valves according to claim 1, characterized in that, A floating compensation device (6) is connected in series between the adjustable centering gripper (3) and the displacement adjustment mechanism (5) to passively adapt to the posture deviation of the valve body end face and buffer the clamping impact during the clamping process.

3. The interlocking flexible gripper adapted to multi-specification valves according to claim 2, characterized in that, The top of the reference support (4) is fixed to the bottom surface of the mounting base (1), and the fixing centering claw (2) is fixedly installed at the bottom end of the reference support (4). The displacement adjustment mechanism (5) includes a lateral adjustment component (51) and a longitudinal adjustment component (52). The lateral adjustment component (51) is installed on the bottom surface of the mounting base (1) and located on the side of the reference support (4). The longitudinal adjustment component (52) is installed on the moving end of the lateral adjustment component (51). The top end of the floating compensation device (6) is fixed to the moving end of the longitudinal adjustment component (52). The adjustable centering gripper (3) is installed on the bottom end of the floating compensation device (6). The lateral adjustment component (51) is used to drive the adjustable centering jaw (3) to move closer to or further away from the fixed centering jaw (2) in a direction parallel to the bottom surface of the mounting base (1); the longitudinal adjustment component (52) is used to drive the adjustable centering jaw (3) to reciprocate in a direction perpendicular to the bottom surface of the mounting base (1).

4. The interlocking flexible gripper adapted to multi-specification valves according to claim 3, characterized in that, The floating compensation device (6) includes a top flange (61), a floating compensation module (62), and a bottom flange (63) connected in sequence. The top flange (61) is fixedly connected to the moving end of the longitudinal adjustment component (52), and the bottom flange (63) is fixedly connected to the fixed end of the adjustable centering gripper (3).

5. The interlocking flexible gripper adapted to multi-specification valves according to claim 4, characterized in that, The floating compensation module (62) is an elastic body.

6. The interlocking flexible gripper adapted to multi-specification valves according to claim 3, characterized in that, The lateral adjustment component (51) is a servo slide; the reference support (4) is located on one side of the sliding direction of the moving end of the servo slide.

7. The interlocking flexible gripper adapted to multi-specification valves according to claim 3, characterized in that, The longitudinal adjustment component (52) includes a fixed support (521), a servo cylinder (522), and a guide structure; the top end of the fixed support (521) is fixed to the moving end of the transverse adjustment component (51), the servo cylinder (522) is mounted on the fixed support (521), and its output end can reciprocate in a direction perpendicular to the bottom surface of the mounting base (1); the top end of the floating compensation device (6) is fixed to the output end of the servo cylinder (522); The guide structure includes a guide column flange (524) and guide columns (523) symmetrically arranged on both sides of the servo electric cylinder (522). The guide column flange (524) is fixedly connected to the fixed support (521). One end of the guide column (523) is fixedly connected to the output end of the servo electric cylinder (522). The other end of the guide column (523) passes through the guide column flange (524) and slides with the guide column flange (524).

8. The interlocking flexible gripper adapted to multi-specification valves according to claim 1, characterized in that, The reference support (4) includes a tubular support top flange (41), a tubular support connector (42), and a tubular support bottom flange (43); the tubular support top flange (41), the tubular support connector (42), and the tubular support bottom flange (43) are coaxially fixedly connected in sequence; the top surface of the tubular support top flange (41) is fixed to the bottom surface of the mounting base (1), and the fixed end of the fixing centering claw (2) is connected to the bottom surface of the tubular support bottom flange (43).

9. The interlocking flexible gripper adapted to multi-specification valves according to claim 1, characterized in that, It also includes a quick-change adapter plate (7) set on the top surface of the mounting base (1), which is used to cooperate with the zero-point positioning mother plate pre-installed at the end of the industrial robot to form a quick-change module.

10. The interlocking flexible gripper adapted to multi-specification valves according to claim 1, characterized in that, Both the fixed centering jaw (2) and the adjustable centering jaw (3) include a self-centering vise (31) and a clamping jaw (32) detachably mounted on the jaws of the self-centering vise (31); the clamping surface of the clamping jaw (32) is provided with teeth (321).

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