Clamping tool for impellers

Abstract

The utility model discloses a kind of clamping tool of impeller, comprising: multiple claw bodies and detachably mounted on the claw jaw assembly and installation matrix of claw body spaced distribution along the circumferential direction, one end of claw body is used to install on installation matrix, the other end of claw body is provided with the first installation part for installing claw jaw assembly, first avoiding portion is formed on the side wall of claw body towards the center of installation matrix;Claw jaw assembly includes multiple and corresponding claw body matched claw jaw, claw jaw is provided with the second installation part for and first installation part adaptation, the occlusal positioning portion of claw jaw is set on the side towards the center of installation matrix, the occlusal positioning portion of multiple claw jaw is matched, for the periphery of impeller is clamped, the surface of claw jaw towards the impeller is provided with second avoiding portion, second avoiding portion and first avoiding portion are matched to form combined avoiding structure for avoiding impeller. The present application can avoid interference with the blade of impeller, clamping is stable, and adaptability is better.

Description

Technical Field

[0001] This utility model relates to the field of machining fixtures, and in particular to a clamping fixture for an impeller. Background Technology

[0002] Pump equipment, such as centrifugal pumps, has three main impeller structures: open, semi-open, and closed. These different structures exhibit variations in the form of the cover plate and exposed blades. Generally, all types of impeller castings suffer from casting shrinkage deformation, out-of-roundness of the outer diameter, and large deviations in outer diameter dimensions. Open impellers have no cover plate and the blades are fully exposed; semi-open impellers have a cover plate on only one side, with the blade tips extending freely, and the blade extension angles differ between the two types; closed impellers have double-layered cover plates enclosing the blades with no exposed blade body, but the cover plate end faces can have both flat and inclined structures. All these types of impellers present significant challenges to the universal positioning and stable clamping during machining processes.

[0003] Existing clamping fixtures have many defects when clamping various impellers, such as poor clamping stability, easy interference damage to exposed blades, limited compatibility with a single impeller model, low changeover efficiency, and weak versatility. They cannot achieve stable and efficient clamping and processing of open, semi-open, and closed impellers with different diameters, blade numbers, and cover plate shapes.

[0004] Therefore, it is necessary to propose a clamping fixture for the impeller to solve at least one of the above problems.

[0005] It should be noted that the above introduction to the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of this application and facilitating understanding by those skilled in the art. It should not be assumed that these technical solutions are known to those skilled in the art simply because they have been described in the background section of this application. Utility Model Content

[0006] In view of the shortcomings of the existing technology, the present invention provides a clamping fixture for an impeller, which can avoid interference with the blades of the impeller, provide stable clamping, and has good adaptability.

[0007] The specific technical solution of this utility model embodiment is as follows: A clamping fixture for an impeller includes: a plurality of claws spaced apart along a circumferential direction, a gripper assembly detachably mounted on the claws, and a mounting base. One end of each claw is mounted on the mounting base, and the other end of each claw has a first mounting portion for mounting the gripper assembly. A first clearance portion is formed on the sidewall of each claw facing the center of the mounting base. The gripper assembly includes a plurality of grippers adapted to the corresponding claws. Each gripper has a second mounting portion adapted to the first mounting portion. The first mounting portion and the second mounting portion form an assembly mechanism. Each gripper has a biting positioning portion on the side facing the center of the mounting base. The biting positioning portions of the plurality of grippers cooperate to clamp the periphery of the impeller. A second clearance portion is provided on the surface of each gripper facing the impeller. The second clearance portion and the first clearance portion cooperate to form a combined clearance structure for avoiding the impeller.

[0008] Furthermore, the first clearance portion includes a first inclined sidewall and a second inclined sidewall disposed along the axial direction of the mounting base, the gripper is disposed on a first side of the gripper body along the axial direction, and the mounting base is disposed on a second side of the gripper body along the axial direction; the first inclined sidewall extends inclinedly from the first side to the second side away from the center side of the mounting base, and the second inclined sidewall extends inclinedly from the first side to the second side towards the center side of the mounting base.

[0009] Furthermore, the claw body is provided with a through locking mounting hole, the locking mounting hole having a first end and a second end opposite to each other along the axial direction, the first end of the locking mounting hole extending through to the second inclined sidewall, and the locking mounting hole being provided with an internal threaded section at least partially.

[0010] Furthermore, a limiting step is provided on the side wall of the claw body facing the center of the mounting base on the side of the first clearance portion away from the mounting base, and the limiting step is used to support the biting positioning portion.

[0011] Furthermore, the biting positioning part includes a base and a support part. The base has a first surface and a second surface opposite to each other along the thickness direction. The first surface is used to fit against the claw body. The second surface is provided with the support part and the biting surface protruding from the base. The biting surface and the support part are arranged sequentially along the axial direction of the mounting base.

[0012] Furthermore, the support portion has a support surface for contacting the impeller, the support surface including a first clamping surface extending along a first direction perpendicular to the axial direction and a second clamping surface at a predetermined angle to the first clamping surface, the first clamping surface being closer to the engagement surface than the second clamping surface.

[0013] Furthermore, the biting positioning part includes a base and a support part, the gripper is disposed on a first side of the gripper body along the axial direction of the mounting base, and the mounting base is disposed on a second side of the gripper body along the axial direction; the second clearance part includes a clearance slope, the support part has a support surface for contacting the impeller and a back surface opposite to the support surface, the back surface extends obliquely from the first side toward the second side toward the center side away from the mounting base to form the clearance slope.

[0014] Furthermore, the biting positioning part includes a base and a support part, the second clearance part includes a clearance notch disposed on the base and adjacent to the support part in the horizontal direction, the gripper assembly includes a first gripper, a second gripper and a third gripper, the bases of the first gripper, the second gripper and the third gripper are all provided with the clearance notch, and the clearance notches of the first gripper, the second gripper and the third gripper are disposed in different positions on the base.

[0015] Furthermore, the first gripper has a first clearance notch located on both sides of the support portion, the second gripper has a second clearance notch located on one side of the support portion, and the third gripper has a third clearance notch located on the other side of the support portion.

[0016] Furthermore, the first mounting part includes a first mounting hole or mounting groove, and the second mounting part includes a plug-in structure, which is inserted into the mounting hole or mounting groove.

[0017] Furthermore, the insertion structure is columnar, the first mounting part includes a first mounting hole, the insertion structure is provided with a limiting part at the tail end opposite to the biting positioning part, the clamping fixture also includes an adjusting member, the claw body is also provided with a second mounting hole that communicates with the first mounting hole, the adjusting member is installed in the second mounting hole, and one end of the adjusting member cooperates with the limiting part. When the adjusting member moves along the second mounting hole, it can drive the gripper to move synchronously.

[0018] Furthermore, the second mounting hole is a threaded hole, the adjusting member is an adjusting post with external threads, the limiting part is a limiting groove, and one end of the adjusting post is provided with a protrusion that extends into the limiting groove.

[0019] Furthermore, an operating element adapter is provided at the other end of the adjusting column, which is used to cooperate with the operating element to change the position of the adjusting column.

[0020] The technical solution of this utility model has the following significant beneficial effects: The impeller clamping fixture provided in this application uses a mounting base as its bearing foundation. Multiple jaws are arranged at intervals along the circumferential direction and installed on the mounting base. The upper end of each jaw is provided with a first mounting part and a first clearance part formed on the sidewall facing the center of the fixture. Each jaw of the jaw assembly forms an assembly mechanism by cooperating with its own second mounting part and the first mounting part of the jaw body, realizing the detachable assembly of the jaws. The biting positioning parts of multiple jaws facing the center of the fixture cooperate with each other to enclose and clamp the outer periphery of the impeller. The multi-point encircling structure realizes the centering and positioning of the impeller, evenly distributes the clamping force, effectively improves the clamping wobble and slippage problems caused by the out-of-roundness of the cast impeller outer diameter, and improves the processing stability and operation safety. The gripper has a second clearance portion on its surface facing the impeller. This second clearance portion cooperates with the first clearance portion of the gripper body to form a combined clearance structure. This structure can reserve clearance space for the impeller blades in both axial and radial directions, preventing the tooling from being squeezed, bumped, or interfered with the blades, thus reducing workpiece scrap. In addition, the gripper can be disassembled and replaced separately, and can be adapted to different specifications of impellers without modifying the gripper body and mounting base. This greatly improves the tooling versatility, simplifies the changeover and debugging steps for mixed-flow machining of multiple impeller models, and improves production efficiency. Furthermore, the gripper body and grippers integrate multiple functions such as assembly, positioning, and clearance. The structure is compact and maintains sufficient structural strength, taking into account both the tooling service life and clamping accuracy.

[0021] Specific embodiments of the present invention are disclosed in detail with reference to the following description and accompanying drawings, indicating how the principles of the present invention can be adopted. It should be understood that the embodiments of the present invention are not limited in scope. Features described and / or shown for one embodiment may be used in the same or similar manner in one or more other embodiments, combined with features in other embodiments, or substituted for features in other embodiments. Attached Figure Description

[0022] The accompanying drawings described herein are for illustrative purposes only and are not intended to limit the scope of this invention in any way. Furthermore, the shapes and proportions of the components in the drawings are merely illustrative to aid in understanding the invention and do not specifically limit the shapes and proportions of the components. Those skilled in the art, under the guidance of this invention, can select various possible shapes and proportions to implement this invention according to specific circumstances.

[0023] Figure 1This is a schematic diagram of the impeller clamping fixture provided in the embodiments of this application in the assembly state; Figure 2 This is a front view of an impeller clamping fixture provided in the embodiments of this application in an assembled state; Figure 3 This is a three-dimensional structural diagram of the claw body in a clamping fixture for an impeller provided in the embodiments of this application; Figure 4 This is a front view of the claw body in a clamping fixture for an impeller provided in an embodiment of this application; Figure 5 for Figure 4 Sectional view of AA; Figure 6 This is a schematic diagram of the structure of the adjusting component in a clamping fixture for an impeller provided in an embodiment of this application; Figure 7 This is a front view of an adjusting component in a clamping fixture for an impeller provided in an embodiment of this application. Figure 8 This is a three-dimensional structural diagram of the first gripper in a clamping fixture for an impeller provided in an embodiment of this application; Figure 9 This is one of the schematic diagrams of the first jaw in a clamping fixture for an impeller provided in an embodiment of this application; Figure 10 This is a second schematic diagram of the first jaw in a clamping fixture for an impeller provided in an embodiment of this application; Figure 11 for Figure 9 A magnified view of a portion of point I in the middle; Figure 12 This is a top view of the first jaw in a clamping fixture for an impeller provided in an embodiment of this application; Figure 13 This is a three-dimensional structural diagram of the second gripper in a clamping fixture for an impeller provided in an embodiment of this application; Figure 14 This is a three-dimensional structural diagram of the third gripper in a clamping fixture for an impeller provided in an embodiment of this application.

[0024] The reference numerals in the above figures are as follows: 1. Install the base; 2. Claw body; 21. First Installation Section; 22. First obstacle avoidance section; 221. First inclined sidewall; 222. Second inclined sidewall; 23. Limiting step; 24. Second mounting hole; 25. Locking mounting holes; 251. Internal threaded hole section; 3. Adjusting components; 31. Protrusion; 32. Operating component adapter; 40. Gripper; 41. Second Installation Section; 411. Limiting part; 42. Occlusal positioning part; 421. Matrix; 4211, First Surface; 4212, Second Surface; 422. Support section; 4221. First clamping surface; 4222, Second clamping surface; 43. Second avoidance section; 4223. Avoid slopes; 423. Occlusal surfaces; 433. Avoid the gap; 4331, First Avoidance Gap; 4332, Second Avoidance Gap; 4333, the third avoidance gap; 401. First gripper; 402. Second gripper; 403. Third gripper. Detailed Implementation

[0025] The details of this utility model can be more clearly understood by referring to the accompanying drawings and the description of specific embodiments. However, the specific embodiments of this utility model described herein are only for explaining the purpose of this utility model and should not be construed as limiting this utility model in any way. Under the teachings of this utility model, those skilled in the art can conceive of any possible modifications based on this utility model, and these should all be considered to fall within the scope of this utility model. It should be noted that when an element is referred to as being "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or there may be an intervening element. The terms "mounted," "connected," and "connected" should be interpreted broadly, for example, it can be a mechanical connection or an electrical connection, or it can be a connection within two elements, which can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0027] Currently, in related technologies, the mainstream clamping solutions for processing impellers (including open, semi-open, and closed types) of pump equipment such as centrifugal pumps are mainly divided into: the ordinary three-jaw chuck directly clamps the outer circle of the impeller, a single-model dedicated pressure plate / fixed block tooling, and a universal clamping fixture with detachable jaws. None of the above solutions can adapt to the needs of flexible production of mixed flow of multiple specifications.

[0028] For the conventional three-jaw chuck solution that directly clamps the outer diameter of the impeller, the clamping is achieved by the jaws fitting against the outer diameter of the impeller casting. However, due to the impeller's out-of-roundness in casting and the inconsistent protrusion of the outer sides of each blade, the clamping force of the jaws is uneven. After clamping, the radial runout of the workpiece is large, and the workpiece is prone to slippage and loosening during the machining process. In severe cases, the workpiece may fly out, posing a safety hazard. At the same time, for impellers with different outer diameters and different numbers of blades, it is necessary to repeatedly adjust the jaw opening size or even replace the jaws. The changeover operation is cumbersome and the production efficiency is low.

[0029] For single-model dedicated clamping plate / fixed block tooling, the clamping structure is used to fix the impeller. However, most of them are custom-developed for a single impeller model and cannot be compatible with open, semi-open, and closed impellers with large diameter spans and different cover plate forms. When switching workpiece models, the entire clamping block needs to be replaced or the installation position of the clamping plate needs to be significantly adjusted, lacking flexible adaptability. Moreover, the tooling mostly uses a linear clamping structure, and the clamping components are very prone to spatial interference with the blade tips. The interference problem is particularly prominent when machining impellers with more than four blades. This not only fails to guarantee clamping stability but also causes bumps and scratches on the curved surface of the blades, resulting in workpiece scrap.

[0030] While existing interchangeable jaw fixtures can replace the jaws to accommodate a small number of workpieces of different specifications, they have the following problems: First, the jaws rely on multiple sets of screws for locking, which involves many disassembly and assembly processes and is time-consuming, making it impossible to meet the requirements for rapid production changeover in mixed production lines with multiple batches; Second, the conventional jaws have a right-angled plane structure at the end without a blade avoidance structure, which makes it easy for interference and squeezing to occur when the clamping position is close to the blade, damaging the blade forming surface.

[0031] In addition, existing tooling lacks a bidirectional blade avoidance structure, making it impossible to simultaneously avoid radially extending blades and axial end blades of the impeller; the clamping contact surface lacks an adaptive compensation structure, making it unsuitable for casting out-of-round workpieces; axial positioning is limited to a single plane or a single inclined plane, which cannot be compatible with impellers whose blade outer envelope contours along the axial direction are either straight-circular (the radial distance from the outer edge of the straight-circular impeller blade to the axis of rotation is constant along the axial direction, the outer envelope generatrix is ​​parallel to the impeller's central axis, and the overall shape is cylindrical) or conical (the radial distance from the outer edge of the conical impeller blade to the axis of rotation gradually changes along the axial direction, the outer envelope generatrix is ​​inclined relative to the impeller's central axis, and the overall shape is truncated conical); the overall tooling is suitable for a narrow range of impeller diameters, and one set of fixtures can only cover workpieces in a small size range, requiring multiple sets of tooling to be stocked, resulting in high equipment investment costs and complex on-site management.

[0032] Therefore, there is an urgent need to develop a clamping fixture that can adapt to out-of-round castings, bidirectional avoidance blades, quick claw change, and is applicable to a wide range of diameters.

[0033] This utility model provides a clamping fixture for an impeller, which can avoid interference with the impeller blades, provide stable clamping, and has good adaptability.

[0034] Please refer to the following for comprehensive information. Figures 1 to 14 This application specification provides a clamping fixture for an impeller, which may include: a plurality of claw bodies 2 spaced apart along the circumferential direction, a gripper assembly detachably mounted on the claw bodies 2, and a mounting base 1, wherein one end of the claw body 2 ( Figure 2 The lower end shown is used for mounting on the mounting base 1, and the other end of the claw body 2 ( Figure 2The upper end shown is provided with a first mounting part 21 for mounting the gripper assembly. A first clearance part 22 is formed on the side wall of the gripper body 2 facing the center of the mounting base 1. The gripper assembly includes a plurality of grippers 40 adapted to the corresponding gripper bodies 2. Each gripper 40 is provided with a second mounting part 41 adapted to the first mounting part 21. The first mounting part 21 and the second mounting part 41 form an assembly mechanism. Each gripper 40 is provided with a biting positioning part 42 on the side facing the center of the mounting base 1. The biting positioning parts 42 of the plurality of grippers 40 cooperate to clamp the periphery of the impeller. The surface of the gripper 40 facing the impeller is provided with a second clearance part 43. The second clearance part 43 and the first clearance part 22 cooperate to form a combined clearance structure for avoiding the impeller.

[0035] The impeller clamping fixture provided in this embodiment uses a mounting base 1 as its bearing foundation. Multiple jaws 2 are spaced apart along the circumferential direction and mounted on the mounting base 1. Each jaw 2 has a first mounting portion 21 at its upper end and a first clearance portion 22 formed on its sidewall facing the fixture center. Each jaw 40 of the jaw assembly forms an assembly mechanism by cooperating with its own second mounting portion 41 and the first mounting portion 21 of the jaw 2, enabling detachable assembly of the jaws 40. The engagement positioning portions 42 of the multiple jaws 40 on the side facing the fixture center cooperate to enclose and clamp the outer periphery of the impeller. The multi-point encircling structure achieves impeller centering and positioning, evenly distributing the clamping force, effectively improving the clamping wobble and slippage problems caused by the out-of-roundness of the cast impeller outer diameter, and enhancing processing stability and operation. For industrial safety, the gripper 40 has a second clearance part 43 on its surface facing the impeller. The second clearance part 43 and the first clearance part 22 of the gripper body 2 cooperate to form a combined clearance structure, which can reserve clearance space for the impeller blades in both axial and radial directions, avoiding squeezing, collision and interference between the tooling and the blades, and reducing workpiece scrap. In addition, the gripper 40 can be disassembled and replaced separately, and can be adapted to different specifications of impellers without modifying the gripper body 2 and the mounting base 1, which greatly improves the tooling versatility, simplifies the changeover and debugging steps for mixed flow processing of multiple impeller models, and improves production efficiency. Moreover, the gripper body 2 and gripper 40 integrate multiple functions of assembly, positioning and clearance, with a compact structure and sufficient structural strength, taking into account both tooling service life and clamping accuracy.

[0036] The present application will now be described in detail with reference to the accompanying drawings and embodiments.

[0037] The clamping fixture for the impeller mainly includes: multiple claw bodies 2 spaced apart along the circumferential direction, a gripper assembly detachably mounted on the claw bodies 2, and a mounting base 1.

[0038] Please refer to the following: Figure 1 , Figure 2 and Figure 3Specifically, the claw body 2 may include three groups, or more than three groups, such as four or five groups. In the embodiments and drawings of this application, the claw body 2 including three groups is used as an example for detailed description.

[0039] The claw body 2 can be a monolithic block structure that extends longitudinally along the axial direction X of the mounting base 1. For example, when using... Figure 2 As shown in the figure, when installed on a vertical machining equipment, the claw body 2 can be a one-piece block structure extending longitudinally along the height direction. This one-piece structure reduces splicing gaps, increases overall rigidity, and makes it less prone to deformation during clamping. Of course, this clamping fixture can also be rotated 90° and installed on a horizontal machining equipment. In the embodiments and figures of this application, this is mainly used... Figure 2 The angle shown is given as an example. When it is installed on a horizontal machining equipment or on a machine that performs machining in other positions, it is only necessary to rotate the installation angle of the clamping fixture accordingly. This application will not repeat the details here.

[0040] The upper end of the claw body 2 is used to mount the gripper 40, and the lower end of the claw body 2 is used to mount it on the mounting base 1. The mounting base 1 can be a chuck, or it can be other forms of mounting base 1. In this embodiment, a three-jaw chuck is used as an example for illustration.

[0041] Specifically, three sets of claw bodies 2 are evenly arranged at 120° intervals along the circumference. The lower end of each claw body 2 is mounted on the sliding guide rail of the three-jaw chuck, and its position can be adjusted radially along the sliding guide rail to accommodate impellers of different outer diameters. Of course, this invention is not limited to this, and those skilled in the art can choose a non-uniform circumferential arrangement as needed. In use, the claw bodies 2 work in conjunction with the three-jaw chuck to achieve synchronous radial feeding, automatic centering and clamping, uniform force distribution, and can accommodate various impellers of different diameters, including open impellers, semi-open impellers, and closed impellers.

[0042] Please refer to the following: Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 In one embodiment, the first mounting part 21 includes a first mounting hole or mounting groove, and the second mounting part 41 includes a plug-in structure that is inserted into the mounting hole or mounting groove.

[0043] In this embodiment, the gripper 40 and the gripper body 2 are mainly connected by a plug-in assembly mechanism. During assembly, the plug-in structure of the gripper 40 is directly pushed into the first mounting part 21 of the gripper body 2 to complete the pre-positioning, without the need for complicated alignment operations, making disassembly and assembly convenient. In addition, the standardized plug-in structure can realize the interchangeable installation of different models of grippers 40. One set of gripper body 2 can be matched with multiple compatible grippers 40, reducing the number of tooling parts required.

[0044] Furthermore, the insertion structure is columnar, for example, cylindrical. The first mounting part 21 includes a first mounting hole. The insertion structure is provided with a limiting part 411 away from the tail end of the biting positioning part 42. The clamping fixture also includes an adjusting member 3. The claw body 2 is also provided with a second mounting hole 24 that communicates with the first mounting hole. The adjusting member 3 is installed in the second mounting hole 24, and one end of the adjusting member 3 cooperates with the limiting part 411. When the adjusting member 3 moves along the second mounting hole 24, it can drive the gripper 40 to move synchronously.

[0045] In this embodiment, the columnar plug-in structure cooperates with the first mounting hole, and the plug-in is smooth and there is no radial movement, which helps to ensure the clamping and positioning accuracy of the gripper 40. The adjusting member 3 and the limiting part 411 at the tail end of the plug-in structure form a linkage structure, which can drive the gripper 40 to move slightly along the axial direction of the first mounting hole without disassembling the gripper 40. When there is a local dimensional deviation in a single impeller casting, it can be corrected without replacing the entire gripper 40, and the adjustment is more flexible.

[0046] The adjusting component 3 can be in the form of a threaded adjusting column, a push screw, an eccentric adjusting shaft, etc., and can be set according to the tooling fine-tuning stroke and processing conditions.

[0047] Please refer to the following: Figures 3 to 7 Specifically, the second mounting hole 24 is a threaded hole, the adjusting member 3 is an adjusting post with external threads, the limiting part 411 is a limiting groove, and one end of the adjusting post is provided with a protrusion 31, which extends into the limiting groove.

[0048] In this embodiment, the threaded hole and the adjusting column with external thread form a threaded pair transmission. Rotating the adjusting column can realize stepless axial feed and the fine adjustment stroke is continuously controllable. The protrusion 31 at the end of the adjusting column is embedded in the end limiting groove of the plug-in structure to form axial linkage limiting. There will be no slippage or misalignment during transmission. The fine adjustment action is stable and reliable and can accurately control the axial clamping position of the gripper 40.

[0049] Furthermore, an operating element adapter 32 is provided at the other end of the adjusting column. The operating element adapter 32 is used to cooperate with the operating element to change the position of the adjusting column.

[0050] Specifically, the adapter part 32 of the operating component can adopt a regular hexagonal inner hole, which can be matched with a standard internal hex wrench for operation, without the need for special customized tools, and the on-site debugging in the workshop is convenient.

[0051] In one embodiment, a limiting step 23 is provided on the side wall of the claw body 2 facing the center of the mounting base 1 above the first clearance portion 22, and the limiting step 23 is used to support the biting positioning portion 42.

[0052] In this embodiment, the limiting step 23 forms a support reference, which can support the end face of the impeller cover plate during clamping, share the load of the jaw 40 meshing surface 423, prevent the impeller from moving during processing, and improve the overall clamping rigidity and positioning stability.

[0053] like Figure 8 , Figure 9 , Figure 10 and Figure 11 As shown, the biting positioning part 42 further includes a base 421, the base 421 having a first surface 4211 and a second surface 4212 opposite to each other along the thickness direction, the first surface 4211 being used to fit against the claw body 2, the lower part of the second surface 4212 being provided with a support part 422 protruding from the base 421, and the upper part of the second surface 4212 being provided with a biting surface 423.

[0054] The biting and positioning part 42 relies on the first surface 4211 to fit tightly with the claw body 2, ensuring that the gripper 40 is not tilted and the positioning reference is uniform after being assembled on the claw body 2. The upper biting surface 423 directly fits against the outer circle of the impeller to achieve radial clamping, and the lower support part 422 supports the impeller cover plate. Radial clamping and axial support are integrated into one unit, simplifying the number of parts. Among them, the biting surface 423 can adopt a multi-tooth array shape, and multi-point contact compensates for the out-of-roundness of the casting, making the clamping force more uniform and improving the stability and reliability of the clamping.

[0055] In one specific embodiment, the upper surface of the support 422 includes a first clamping surface 4221 extending in a horizontal direction and a second clamping surface 4222 at a predetermined angle to the first clamping surface 4221, wherein the first clamping surface 4221 is closer to the engagement surface 423 than the second clamping surface 4222.

[0056] In this embodiment, the first clamping surface 4221 and the second clamping surface 4222 constitute a dual-surface composite positioning structure, which is compatible with two types of mainstream impeller cover plates. The horizontally extending first clamping surface 4221 is adapted to impellers with flat end faces on the cover plate, while the inclined second clamping surface 4222 is adapted to impellers with inclined surfaces on the cover plate. The same gripper 40 can be used to accommodate two different workpiece structures without replacement, significantly improving the tooling's versatility and reducing the frequency of gripper 40 replacement during model changes.

[0057] In this embodiment, the first clearance portion 22 is mainly used to avoid the impeller blades. The first clearance portion 22 is formed on the inner sidewall of the claw body 2 facing the center of the mounting base. Its core function is to radially avoid the blade body extending outwards from the impeller. The structural form can be flexibly set according to the impeller blade tilt angle, blade thickness, and impeller outer diameter specifications. The first clearance portion 22 can be a double-sloping surface combination structure, an integral clearance groove structure, a single-sloping surface clearance structure, a stepped clearance structure, or an arc clearance structure, etc. The following explanation uses a double-sloping surface combination structure as an example.

[0058] In one embodiment, the first clearance portion 22 includes a first inclined sidewall 221 and a second inclined sidewall 222 disposed vertically along the height direction. The first inclined sidewall 221 extends inclinedly downward from top to bottom toward the center side away from the mounting base 1, and the second inclined sidewall 222 extends inclinedly downward from top to bottom toward the center side close to the mounting base 1.

[0059] In this embodiment, the first inclined sidewall 221 and the second inclined sidewall 222, which are arranged vertically, cooperate to form the first clearance portion 22 on the side of the claw body 2. The overall inclination angle of the first inclined sidewall 221 and the second inclined sidewall 222 can be between 15° and 30°, which can be adapted to the outer diameter extension angle of the impeller blade, and avoid the outwardly extending blade body and the impeller locking mounting hole 25 in the radial direction, thus eliminating radial interference. In addition, the two inclined surface combination structure of the first clearance portion 22 can optimize the stress distribution of the claw body 2, and maintain sufficient wall thickness after the clearance area is opened, so as to ensure the load-bearing strength of the claw body 2 and withstand cutting impact without deformation or cracking.

[0060] Furthermore, the claw body 2 is provided with a through locking mounting hole 25 along the height direction. The locking mounting hole 25 has an upper end and a lower end along the height direction. The upper end of the locking mounting hole 25 extends through to the second inclined sidewall 222. The locking mounting hole 25 is provided with an internal threaded hole section 251 at least partially.

[0061] The locking mounting hole 25 is used to insert a locking screw. Specifically, the locking mounting hole 25 has an internally threaded section 251 near its lower end. The locking screw passes through the locking mounting hole 25 and engages with the internally threaded section 251 to fix the claw body 2 onto the three-jaw chuck. The number of locking mounting holes 25 can be one or two. For example, two locking mounting holes 25 can be arranged at intervals along the radial direction of the three-jaw chuck. When a locking screw is installed in both locking mounting holes 25, the claw body 2 can be reliably fixed onto the three-jaw chuck.

[0062] The locking mounting hole 25 is located at the second inclined side wall 222, which provides assembly space for the locking screw without damaging the overall inclined profile of the first clearance part 22 and without affecting the blade clearance effect.

[0063] In this embodiment, the second clearance portion 43 is formed on the surface of the gripper 40 facing the impeller, and it is used to clear the impeller end and the circumferentially distributed blades from both circumferential and axial dimensions. The second clearance portion 43 can adopt any single structure or a combination of multiple structures: a structure in which a clearance slope 4223 is formed on the lower side of the support portion 422, and a lateral clearance notch structure in which a clearance notch 433 is opened on the side of the base 421.

[0064] The avoidance slope 4223 on the lower side of the support part 422 is used to avoid the axial end blades of the impeller, and the avoidance notch 433 on the base 421 adjacent to the support part 422 is used to avoid the circumferentially extended blades of the impeller. The two can be set independently or integrated simultaneously on the same gripper 40 to form a circumferential and axial composite avoidance structure, which is suitable for various open impellers, semi-open impellers and closed impellers with different numbers of blades such as four-blade, five-blade, and six-blade, and different blade extension dimensions.

[0065] In one embodiment, the second avoidance portion 43 includes an avoidance slope 4223, the lower surface of the support portion 422 extending obliquely downward from top to bottom toward the center side away from the mounting base 1 to form the avoidance slope 4223.

[0066] By utilizing the lower surface of the support part 422 to form an avoidance slope 4223, the inclined surface formed by the avoidance slope 4223 reserves space for axial blades, so that the blades at the axial end of the impeller will not be squeezed when clamped; at the same time, the inclined slope can disperse the clamping stress, prevent the sharp corners of the bottom of the jaws 40 from making hard contact with the surface of the impeller blank, prevent indentations and local deformation on the outer wall of the impeller, and take into account both the avoidance function and the workpiece protection effect.

[0067] Please refer to the following: Figures 8 to 14Furthermore, the gripper assembly may include a first gripper 401, a second gripper 402, and a third gripper 403, wherein the first gripper 401, the second gripper 402, and the third gripper 403 are evenly distributed at 120° intervals in the circumferential direction, and the second clearance portion 43 of the first gripper 401, the second gripper 402, and the third gripper 403 have different shapes and / or sizes.

[0068] In one embodiment, the second clearance portion 43 includes a clearance notch 433 disposed on the base 421 and horizontally adjacent to the support portion 422. The gripper assembly includes a first gripper 401, a second gripper 402, and a third gripper 403. The base 421 of the first gripper 401, the second gripper 402, and the third gripper 403 are all provided with the clearance notch 433. The clearance notches 433 of the first gripper 401, the second gripper 402, and the third gripper 403 are located at different positions on the base 421.

[0069] Specifically, such as Figures 8 to 12 As shown, the first gripper 401 has a first clearance notch 4331, which is disposed on both sides of the support portion 422; as Figure 13 As shown, the second gripper 402 has a second clearance notch 4332, which is disposed on one side of the support portion 422; as Figure 14 As shown, the third gripper 403 has a third clearance notch 4333, which is located on the other side of the support portion 422. The transition between the support portion 422 and the clearance notch 433 can be achieved by a ramp surface, which, together with the clearance notch 433, forms a continuous, smooth, and spacious circumferential clearance area.

[0070] For a three-jaw chuck, it is provided with three sets of limiting components (such as sliding guides, the cross-section of which can be dovetail or T-shaped, etc., which have a certain limiting effect on the jaw body 2), and the three limiting components are equally divided in a 120° circumferential direction. The jaw body 2 mounted on the three-jaw chuck and the jaws 40 mounted on each jaw body 2 are also distributed at 120° circumferential intervals in the circumferential direction.

[0071] As for impellers, they are divided into even-numbered blade structures (such as 4 blades, 6 blades, etc.) and odd-numbered blade structures (such as 5 blades, etc.). The circumference of the blades is divided into equal angles, which do not match the indexing angle of the three jaws of the tooling. If the three jaws are 40° out of shape and are completely identical, the clamping position is likely to be directly opposite the blade body, resulting in squeezing, collision and interference.

[0072] In this embodiment, the clamping fixture of the impeller can be composed of one of each of three types of clamps with different notches. Specifically, in this embodiment, the three clamps 40 are designed differently: for example, the positions of the clearance notches 433 on the base 421 can be arranged differently to form a first clearance notch 4331 with slots on both sides, a second clearance notch 4332 with slots on one side, and a third clearance notch 4333 with slots on the other side.

[0073] The three different shapes of the first jaw 401, the second jaw 402, and the third jaw 403 work together to compensate for the difference between the 120° indexing of the three jaws of the fixture and the equal division angle of the impeller blade circumference, so that the three sets of clamping points fall uniformly in the gap area between adjacent blades of the impeller. Regardless of whether the open impeller has an odd or even number of blades, the avoidance notch 433 can achieve blade avoidance, thereby eliminating spatial interference between the clamping fixture and the blade tip, preventing scratches on the blade surface and scrapping of the workpiece; without replacing the entire set of jaws 2 or the fixture base, the three sets of differentiated jaws 40 can be used to accommodate impellers with various numbers of blades, greatly improving the tooling adaptability and reducing the fixture investment cost for machining multiple impeller models.

[0074] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from the others. Similar or identical parts between embodiments can be referred to interchangeably. The above embodiments are only for illustrating the technical concept and features of this utility model, and are intended to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They should not be construed as limiting the scope of protection of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be included within the scope of protection of this utility model.

Claims

1. A clamping fixture for an impeller, characterized in that, The impeller clamping fixture includes: a plurality of claw bodies (2) spaced apart along the circumferential direction, a gripper assembly detachably mounted on the claw bodies (2), and a mounting base (1). One end of the claw body (2) is used to be mounted on the mounting base (1), and the other end of the claw body (2) is provided with a first mounting part (21) for mounting the claw assembly. A first clearance part (22) is formed on the side wall of the claw body (2) facing the center of the mounting base (1). The gripper assembly includes multiple grippers (40) adapted to the corresponding gripper body (2). Each gripper (40) is provided with a second mounting part (41) adapted to the first mounting part (21). The first mounting part (21) and the second mounting part (41) form an assembly mechanism. Each gripper (40) is provided with a biting positioning part (42) on one side facing the center of the mounting base (1). The biting positioning parts (42) of the multiple grippers (40) cooperate to clamp the periphery of the impeller. Each gripper (40) is provided with a second clearance part (43) on the surface facing the impeller. The second clearance part (43) and the first clearance part (22) cooperate to form a combined clearance structure for clearance of the impeller.

2. The impeller clamping fixture as described in claim 1, characterized in that, The first clearance portion (22) includes a first inclined sidewall (221) and a second inclined sidewall (222) disposed along the axial direction of the mounting base (1). The gripper (40) is disposed on the first side of the gripper body (2) along the axial direction, and the mounting base (1) is disposed on the second side of the gripper body (2) along the axial direction; The first inclined sidewall (221) extends obliquely from the first side to the second side away from the center of the mounting base (1), and the second inclined sidewall (222) extends obliquely from the first side to the second side closer to the center of the mounting base (1).

3. The impeller clamping fixture as described in claim 2, characterized in that, The claw body (2) is provided with a through locking mounting hole (25), the locking mounting hole (25) has a first end and a second end opposite to each other along the axial direction, the first end of the locking mounting hole (25) extends through to the second inclined sidewall (222), and the locking mounting hole (25) is provided with an internal threaded hole section (251) at least partially.

4. The impeller clamping fixture as described in claim 2, characterized in that, On the side wall of the claw body (2) facing the center of the mounting base (1), a limiting step (23) is provided on the side of the first clearance part (22) away from the mounting base (1). The limiting step (23) is used to support the biting positioning part (42).

5. The impeller clamping fixture as described in claim 4, characterized in that, The biting positioning part (42) includes a base (421) and a support part (422). The base (421) has a first surface (4211) and a second surface (4212) opposite to each other along the thickness direction. The first surface (4211) is used to fit with the claw body (2). The second surface (4212) is provided with the support part (422) and the biting surface (423) protruding from the base (421). The biting surface (423) and the support part (422) are arranged sequentially along the axial direction of the mounting base (1).

6. The impeller clamping fixture as described in claim 5, characterized in that, The support portion (422) has a support surface for contacting the impeller. The support surface includes a first clamping surface (4221) extending along a first direction perpendicular to the axis and a second clamping surface (4222) at a predetermined angle to the first clamping surface (4221). The first clamping surface (4221) is closer to the engagement surface (423) than the second clamping surface (4222).

7. The impeller clamping fixture as described in claim 1, characterized in that, The bite positioning part (42) includes a base (421) and a support part (422). The gripper (40) is disposed on the first side of the gripper body (2) along the axial direction of the mounting base (1), and the mounting base (1) is disposed on the second side of the gripper body (2) along the axial direction. The second clearance portion (43) includes a clearance slope (4223), and the support portion (422) has a support surface for contacting the impeller and a back surface opposite to the support surface. The back surface extends obliquely from the first side toward the second side toward the center side away from the mounting base (1) to form the clearance slope (4223).

8. The impeller clamping fixture as described in claim 1 or 7, characterized in that, The biting positioning part (42) includes a base (421) and a support part (422). The second clearance part (43) includes a clearance notch (433) disposed on the base (421) and adjacent to the support part (422) in the horizontal direction. The gripper assembly includes a first gripper (401), a second gripper (402) and a third gripper (403). The base (421) of the first gripper (401), the second gripper (402) and the third gripper (403) are all provided with the clearance notch (433). The clearance notches (433) of the first gripper (401), the second gripper (402) and the third gripper (403) are located at different positions on the base (421).

9. The impeller clamping fixture as described in claim 8, characterized in that, The first gripper (401) has a first clearance notch (4331) which is disposed on both sides of the support portion (422). The second gripper (402) has a second clearance notch (4332) which is disposed on one side of the support portion (422). The third gripper (403) has a third clearance notch (4333) which is disposed on the other side of the support portion (422).

10. The impeller clamping fixture as described in claim 1, characterized in that, The first mounting part (21) includes a first mounting hole or mounting groove, and the second mounting part (41) includes a plug-in structure, which is inserted into the mounting hole or mounting groove.

11. The impeller clamping fixture as described in claim 10, characterized in that, The plug-in structure is columnar. The first mounting part (21) includes a first mounting hole. The plug-in structure is provided with a limiting part (411) at the tail end away from the biting positioning part (42). The clamping fixture also includes an adjusting member (3). The claw body (2) is also provided with a second mounting hole (24) that communicates with the first mounting hole. The adjusting member (3) is installed in the second mounting hole (24), and one end of the adjusting member (3) cooperates with the limiting part (411). When the adjusting member (3) moves along the second mounting hole (24), it can drive the gripper (40) to move synchronously.

12. The impeller clamping fixture as described in claim 11, characterized in that, The second mounting hole (24) is a threaded hole, the adjusting member (3) is an adjusting column with external threads, the limiting part (411) is a limiting groove, and one end of the adjusting column is provided with a protrusion (31), which extends into the limiting groove.

13. The impeller clamping fixture as described in claim 12, characterized in that, The other end of the adjusting column is provided with an operating element adapter (32), which is used to cooperate with the operating element to change the position of the adjusting column.

Images