An inner shuttle, guide rail and oil-free shuttle

Abstract

The utility model discloses an inner shuttle, guide rail and oilless rotating shuttle, oilless rotating shuttle, including outer shuttle, shuttle board, shuttle skin, guide rail and by the split inner shuttle of inner shuttle I, inner shuttle II, be equipped with the groove or the convex structure on the joint surface of inner shuttle I and inner shuttle II, set up the limit groove / convex with it on the guide rail, be used for realizing the accurate positioning and integral fixed of guide rail and inner shuttle, inner shuttle I, inner shuttle II are connected through screw assembly, and the guide rail can be independently disassembled, this structure avoids the complex technology and cooling deformation problem of traditional guide rail injection molding, realizes high accuracy assembly and maintainability, promotes the wear resistance and operating stability of oilless rotating shuttle, prolongs the life and reduces manufacturing cost, is applicable to all kinds of high -speed industrial sewing machine.

Description

Technical Field

[0001] This utility model belongs to the field of rotary hooks, specifically relating to an inner shuttle, a guide rail, and an oil-free rotary hook. Background Technology

[0002] The rotary hook is a key moving component of a sewing machine, and its structural precision directly determines the overall sewing stability and high-speed performance of the machine. Traditional rotary hooks typically consist of an outer hook, an inner hook, a bobbin, and a bobbin skin. The inner hook acts as the center of rotation, transmitting coils with the outer hook through high-speed relative motion. Existing rotary hooks require continuous lubrication during operation to reduce friction and wear; however, when the rotary hook speed reaches 8000–10000 r / min, the problems of lubricant evaporation, splashing, and contamination become increasingly prominent, affecting not only the overall cleanliness of the sewing machine but also leading to frequent maintenance and increased oil consumption.

[0003] To reduce reliance on lubrication, existing technologies have proposed "oil-free rotary shuttle" solutions. For example, CN221854978U discloses a rotary shuttle structure that replaces the metal friction pair with a polymer self-lubricating material. This solution separates the inner shuttle and the guide rail, with the guide rail made of polymer material and injection molded onto the metal inner shuttle, thus achieving long-term oil-free operation. Although this technology improves lubrication at the material level, it has the following significant drawbacks:

[0004] High manufacturing complexity: The inner shuttle is an irregularly shaped, non-standard precision part, and the guide rail is suspended around the perimeter. The injection molding process has extremely high requirements for mold precision, demolding angle and cooling control.

[0005] High deformation and scrap rate: Polymer materials are prone to shrinkage or warping during the cooling stage, which leads to excessive form and position errors of the guide rail, thus affecting the assembly accuracy and operation balance of the rotary shuttle.

[0006] High cost and losses: The molds are expensive and there are many processing steps. If the guide rail of a batch is deformed, the entire batch of inner shuttles will be scrapped. Repair is not disassembled: The guide rail and inner shuttle are injection molded as a whole and cannot be replaced separately, which increases the cost of later maintenance. Utility Model Content

[0007] This invention provides an oil-free rotary hook, employing a split internal shuttle and a newly matched guide rail. By modularizing the internal shuttle structure into two parts, internal shuttle I and internal shuttle II, and introducing a limiting groove / protrusion integrated fit structure between their mating surfaces and the guide rail, precise positioning and fixation of the guide rail and internal shuttle are achieved. This structure eliminates the need for complex injection molds and can achieve direct matching through machining.

[0008] An inner shuttle of an oil-free rotary shuttle, the inner shuttle being composed of inner shuttle I and inner shuttle II;

[0009] The inner shuttle I and inner shuttle II are provided with groove I and / or protrusion I on their separate mating surfaces for fixing the guide rail and inner shuttle together.

[0010] Groove I on inner shuttle I and / or inner shuttle II includes independent grooves and split grooves;

[0011] The split-type slots are combined into a combined slot with an extended and connected cavity by the combination of inner shuttle I and inner shuttle II;

[0012] An independent slot is a single cavity slot where the cavity is only located on inner shuttle I or inner shuttle II;

[0013] To address the problems of complex molding processes, high mold costs, easy deformation of guide rails, difficulty in controlling assembly precision, and lack of replaceability for maintenance associated with existing oil-free rotary shuttle guides, a new oil-free rotary shuttle with a split inner shuttle and matching guide rail structure is proposed. This involves designing the inner shuttle as a split structure of inner shuttle I and inner shuttle II, with groove I and / or protrusion I on their mating surfaces. Simultaneously, a matching limiting groove / protrusion structure is provided on the guide rail, enabling the guide rail to achieve mechanical positioning and integral fixation with the inner shuttle without relying on injection molding. This structure allows for flexible selection based on different precision requirements through various mating methods such as independent grooves, split grooves, independent protrusions, and split protrusions. The guide rail and inner shuttle are fixed with screws, forming a high-strength, detachable positioning system.

[0014] The technical solution provided in this application also has the following technical features:

[0015] Preferably, in one embodiment of this application, the protrusion I on inner shuttle I and / or inner shuttle II includes independent protrusions and separate protrusions;

[0016] The separate protrusions are combined into an extended integrated protrusion by the combination of inner shuttle I and inner shuttle II;

[0017] An independent protrusion is a single protrusion that is only provided on inner shuttle I or inner shuttle II.

[0018] Preferably, in one embodiment of this application, mounting holes are provided on inner shuttle I and inner shuttle II, and inner shuttle I and inner shuttle II are fixed by screws.

[0019] Preferably, in one embodiment of this application, the shape of the independent protrusion or / and the split protrusion is one or a combination of the shapes of a cylinder, a conical cylinder, an ellipsoid, a sphere, and a square cylinder, and the combination shape includes parts of at least two shapes.

[0020] Preferably, in one embodiment of this application, the cavity shape of the independent groove and / or the split groove is any one of cylindrical, semi-cylindrical, conical, semi-conical, semi-ellipsoidal, spherical, hemispherical or partially spherical.

[0021] Preferably, in one embodiment of this application, the split groove is semi-circular in shape, and the independent groove is a dovetail groove.

[0022] Preferably, in one embodiment of this application, the split protrusion is a semi-cylindrical protrusion, and the independent protrusion is a dovetail platform.

[0023] Preferably, in one embodiment of this application, an oil-free rotary shuttle guide rail is provided with a groove I and / or a protrusion I for limiting the integral fixation of the guide rail and the inner shuttle;

[0024] Slot I, including independent slots and / or split slots;

[0025] Protrusion I includes independent protrusions and / or separate protrusions, and the upper end face of protrusion I is aligned with the mating surfaces of inner shuttle I and inner shuttle II.

[0026] Preferably, in one embodiment of this application, the shape of the independent protrusion or / and the split protrusion is one or a combination of the shapes of a cylinder, a conical cylinder, an ellipsoid, a sphere, and a square cylinder, and the combination shape includes parts of at least two shapes.

[0027] Preferably, in one embodiment of this application, the cavity shape of the independent groove and / or the split groove is any one of cylindrical, semi-cylindrical, conical, semi-conical, semi-ellipsoidal, spherical, hemispherical or partially spherical.

[0028] Preferably, in one embodiment of this application, an oil-free rotary shuttle includes an outer shuttle, a shuttle plate, and a shuttle skin, with the outer shuttle, shuttle plate, and shuttle skin being equipped with the aforementioned inner shuttle; a groove I and / or a protrusion I are provided on the guide rail, which are used to limit and connect the split joint surfaces of the inner shuttle I and the inner shuttle II; the inner shuttle I and the inner shuttle II are integrally fixed to the guide rail, the inner shuttle I, and the inner shuttle II by limiting the groove I and / or the protrusion I of the guide rail.

[0029] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

[0030] The technical solution of this application overcomes the defects of existing oil-free rotary shuttle guides, such as processing deformation, irreparable structure, and high batch scrap rate, and achieves the following technical progress:

[0031] 1. In order to solve the problems of complex molding and high mold cost of oil-free rotary shuttle guides, a split structure design of inner shuttle I, inner shuttle II and independent guide rail is adopted. Precise matching is achieved through machining, which overcomes the defects of easy deformation and long processing cycle of traditional injection molded guide rails, and achieves the technical effects of simplified manufacturing process, improved processing efficiency and significantly reduced cost.

[0032] 2. In order to solve the problems of difficulty in ensuring the assembly accuracy of the rotary shuttle and the swaying during operation, a groove / protrusion limiting structure is set on the mating surface of inner shuttle I and inner shuttle II and on the guide rail. This overcomes the defects of unstable guide rail positioning and large concentricity deviation, and achieves the technical effects of improved assembly accuracy, enhanced rotational stability and reduced running noise.

[0033] 3. In order to solve the problems of traditional oilless rotary hooks being non-repairable and having a high scrap rate, a detachable screw connection method is adopted, which allows the guide rail and inner shuttle to be modularly assembled. This overcomes the defect that the integral injection molded structure cannot replace individual parts. Inner shuttle I, inner shuttle II and guide rail can all be replaced, which has the technical effects of convenient maintenance, reusable parts and extended service life.

[0034] 4. In order to solve the problems of easy wear and uneven stress on polymer guide rails under high-speed operation, the guide rail load is distributed by split limiting and multi-point support structure, which overcomes the defects of local wear and deformation of traditional guide rails and achieves technical effects such as improved wear resistance, enhanced impact resistance, and stable and reliable long-term oil-free operation. Attached Figure Description

[0035] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0036] Figure 1 This is a perspective view of an oil-free rotary hook according to the present invention;

[0037] Figure 2 This utility model provides a three-dimensional guide rail for an oil-free rotary hook. Figure 1 ;

[0038] Figure 3 These are two perspective views of the inner shuttle I of an oil-free rotary shuttle of this utility model, placed in both the front and back positions.

[0039] Figure 4 This is a perspective view of the inner shuttle II of an oil-free rotary shuttle according to this utility model;

[0040] Figure 5 This utility model provides a three-dimensional guide rail for an oil-free rotary hook. Figure 2 ;

[0041] Figure 6 This is an exploded view of an oil-free rotary shuttle according to this utility model;

[0042] Figure 7 This is an exploded view of the split shuttle frame of an oil-free rotary shuttle according to this utility model;

[0043] Figure 8 for Figure 1 Color images;

[0044] Figure 9 for Figure 6 Color images;

[0045] Figure 10 for Figure 7 Color images;

[0046] Components in the diagram:

[0047] 1. Outer shuttle

[0048] 2. Shuttle plate

[0049] 3. Fiberboard

[0050] 4. Guide rail

[0051] 401. Cylinder

[0052] 402, Swallowtail Terrace

[0053] 4011, Align the steps

[0054] 5. Inner shuttle I

[0055] 501. Semicircular Groove I

[0056] 502, threaded hole

[0057] 6. Inner shuttle II

[0058] 601, Semicircular Groove II

[0059] 602, dovetail groove

[0060] 603, Through Hole

[0061] 7. Screws. Detailed Implementation

[0062] The specific embodiments of this application will be further described in detail below with reference to the accompanying drawings. These embodiments are only for illustrating this application and are not intended to limit the scope of this utility model.

[0063] In the description of this utility model, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They 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, and therefore should not be construed as a limitation on this utility model. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0064] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0065] Furthermore, in the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0066] like Figures 1-10 An inner shuttle of an oil-free rotary shuttle, the inner shuttle being composed of inner shuttle I5 and inner shuttle II6;

[0067] The inner shuttle I5 and inner shuttle II6 are provided with groove I and / or protrusion I on their separate mating surfaces for fixing the guide rail 4 and the inner shuttle together.

[0068] Groove I on inner shuttle I5 or / and inner shuttle II6 includes independent grooves and split grooves;

[0069] The split-type slots are combined into a combined slot with an extended cavity by the combination of inner shuttle I5 and inner shuttle II6;

[0070] An independent slot is a single cavity slot where the cavity is only located on inner shuttle I5 or inner shuttle II6;

[0071] The protrusion I on inner shuttle I5 or / and inner shuttle II6 includes independent protrusions and split protrusions;

[0072] The separate protrusions are combined into an extended integrated protrusion by the combination of inner shuttle I5 and inner shuttle II6;

[0073] An independent protrusion is a single protrusion that is only provided on inner shuttle I5 or inner shuttle II6.

[0074] The key implementation points of this application are as follows: The traditional integral inner shuttle is improved into a split structure consisting of inner shuttle I and inner shuttle II. A groove I and / or a protrusion I are provided at the mating surface of the two, and a corresponding limiting structure is formed on the guide rail. The groove and protrusion can be independent or separate. The separate groove and protrusion, after assembly of inner shuttle I and inner shuttle II, form a complete closed cavity or a continuous protrusion structure for precisely positioning the guide rail and achieving stable integrated fixation of the guide rail and inner shuttle. The guide rail can be made of a high-polymer self-lubricating material, and mechanical locking and support are achieved through the limiting structure. Inner shuttle I and inner shuttle II are connected by screws to form a stable integral transmission component.

[0075] The implementation process of this application is as follows: During assembly, the guide rail is first placed between the mating surfaces of inner shuttle I and inner shuttle II, and the guide rail is initially positioned by the engagement of groove I or protrusion I; then, the screws are tightened to engage inner shuttle I and inner shuttle II, and the guide rail is clamped and fixed as a whole with the inner shuttle. When the rotary shuttle is working, the outer shuttle rotates around the inner shuttle at high speed, and the guide rail undertakes the functions of rolling support and sliding guidance, significantly reducing the relative friction between the inner and outer shuttles. Under the support of this limiting structure, the polymer guide rail is subjected to uniform force and has small deformation, enabling long-term oil-free lubrication operation. This structure avoids the deformation and difficult repair problems of injection-molded guide rails, improves the manufacturing precision, operational balance, and maintenance convenience of the rotary shuttle, and realizes reliable operation and extended life of the oil-free rotary shuttle under high-speed conditions.

[0076] Specifically, in one embodiment of this application, inner shuttle I 5 and inner shuttle II 6 are fixed by screw 7, such as... Figure 3 , 4 The inner shuttle I 5 has a threaded hole 502, and the inner shuttle II 6 has a through hole 603. Controllable clamping force is provided by mechanical fasteners, allowing the inner shuttle I and inner shuttle II to form an integral structure after assembly. This ensures the coaxiality of the mating surfaces and the precision of the guide rail's limiting fit. For this precision component, this overcomes the shortcomings of traditional welding or riveting methods, such as easy thermal deformation, difficult assembly, and non-removable parts. This achieves high assembly precision, strong structural stability, and convenient maintenance and replacement. During implementation, the screw preload and screw hole concentricity should be controlled to prevent local stress concentration in the inner shuttle from affecting rotational balance. Anti-loosening fasteners or locking washers can be used to ensure connection reliability during long-term operation. Alternatively, a pin-slot composite locking, a dovetail sliding self-locking structure, or an embedded clamping structure can be used to achieve the same axial fixing and separate positioning effect.

[0077] Specifically, in one embodiment of this application, the shape of the independent protrusion and / or the split protrusion is one or a combination of cylindrical, conical, ellipsoidal, spherical, and square prism shapes, with the combined shape including parts of at least two shapes. By using different cross-sectional shapes, the comprehensive functions of guiding, limiting, and self-locking are achieved. Cylindrical protrusions are easy to process and assemble; spherical or ellipsoidal protrusions can achieve automatic alignment with slight deviations; conical protrusions improve insertion guidance and anti-loosening performance; and square prism protrusions enhance anti-rotation capabilities. This overcomes the defects of inaccurate positioning, easy loosening, or uneven stress distribution of single structures, achieving the technical effects of precise guide rail limiting, strong assembly adaptability, and improved overall shock resistance and wear resistance. Furthermore, multi-segment transition bosses, arc-shaped positioning keys, or a cone-sphere hybrid guide structure can be used to achieve the same limiting and positioning effects.

[0078] Specifically, in one embodiment of this application, the cavity shape of the independent groove and / or split groove is any one of cylindrical, semi-cylindrical, conical, semi-conical, semi-ellipsoidal, spherical, hemispherical, or partially spherical (smaller than a hemisphere). The fitting depth and guiding accuracy of the guide rail or protrusion are controlled by the cavity with different geometric shapes. Cylindrical and semi-cylindrical cavities facilitate linear positioning and machining fit, conical and semi-conical cavities achieve progressive introduction and self-centering effects, and spherical and ellipsoidal cavities can equalize contact stress, reduce wear, and improve running stability. This overcomes the defects of offset, jamming, and early wear in the guiding and positioning process of traditional groove types, and achieves the technical effects of smooth assembly, accurate positioning, and long service life. Furthermore, arc-shaped grooves, hyperboloidal guide grooves, or composite conical groove structures can be used to achieve the same positioning and guiding functions.

[0079] Specifically, in one embodiment of this application, the split groove is semi-circular in shape, and the independent groove is a dovetail groove; the dovetail groove and the dovetail platform constitute a reliable limiting-locking fit, so that the inner shuttle I, inner shuttle II, and guide rail can still maintain a stable connection under the conditions of bearing vibration or off-center load. Moreover, the semi-circular groove is easy to form on the mating surface, forming a symmetrical structure, which is also convenient for manufacturing, processing, inspection, and assembly. During implementation, it is necessary to control the matching accuracy of the dovetail angle and groove depth to ensure smooth assembly and disassembly and uniform force distribution. Alternatively, a "T" shaped groove and "T" shaped boss or a wedge groove and wedge shaped boss structure can be further adopted to achieve the same limiting, locking, and guiding functions.

[0080] like Figure 3 , 4 Semicircular groove I 501 and semicircular groove II 601 are separate grooves, while dovetail groove 602 is an independent groove.

[0081] Specifically, in one embodiment of this application, the split protrusion is a semi-cylindrical protrusion, and the independent protrusion is a dovetail platform, which facilitates manufacturing, processing, inspection, and assembly.

[0082] Specifically, in one embodiment of this application, an oil-free rotary shuttle guide rail is provided, with a groove I and / or a protrusion I on the guide rail 4 for limiting the guide rail 4 and the inner shuttle to be fixed together.

[0083] Slot I, including independent slots and / or split slots;

[0084] Protrusion I includes independent protrusions and / or separate protrusions, and the upper end face of protrusion I is aligned with the mating surfaces of inner shuttle I5 and inner shuttle II6; the shape of the independent protrusion and / or separate protrusion is one or a combination of cylindrical, conical, ellipsoidal, spherical, and square prism shapes, and the combined shape includes parts of at least two shapes; the cavity shape of the independent groove and / or separate groove is any one of cylindrical, semi-cylindrical, conical, semi-conical, semi-ellipsoidal, spherical, hemispherical, or partially spherical (smaller than a hemisphere);

[0085] like Figure 2 The cylinder 401 and the dovetail platform 402 are protrusions I, and some cylinders 401 are provided with alignment steps 4011;

[0086] The main objective is to achieve composite positioning and precise guidance of the guide rail and inner shuttle through multi-form cooperation, enabling the assembly process to have self-calibration capabilities and uniform contact stress distribution during operation. This overcomes the shortcomings of traditional guide rail planar fits, such as low positioning accuracy, concentrated stress, and rapid wear, achieving the technical effects of stable guidance, high assembly accuracy, long structural life, and stable oil-free operation. During implementation, protrusions and grooves can be selected according to the guide rail load characteristics; furthermore, spherical interlocking guide keys or conical-arc groove fit structures can be used to achieve the same guiding and positioning effects.

[0087] Specifically, in one embodiment of this application, an oil-free rotary shuttle includes an outer shuttle 1, a shuttle plate 2, and a shuttle skin 3. The outer shuttle 1, shuttle plate 2, and shuttle skin 3 are equipped with the aforementioned inner shuttle. The guide rail 4 is provided with a groove I and / or a protrusion I, which are used to limit and connect the split joint surfaces of the inner shuttle I 5 and the inner shuttle II 6. The inner shuttle I 5 and the inner shuttle II 6 are integrally fixed to the guide rail 4 by limiting the groove I and / or the protrusion I of the guide rail 4.

[0088] Through this mating structure, the inner shuttle assembly can form a stable guiding and supporting system during operation, reducing relative sliding wear and assembly tolerance transmission errors. This overcomes the shortcomings of existing rotary shuttle systems, such as increased noise, decreased accuracy, and unstable operation caused by insufficient lubrication. This solution achieves high-precision limiting and low-wear guiding under oil-free operation, resulting in a compact structure, reliable positioning, stable operation, and easy maintenance. During implementation, the mating accuracy of the groove and protrusion can be adjusted according to the rotary shuttle's operating speed and load conditions.

[0089] Specifically, in one embodiment of this application, an oil-free rotary shuttle and shuttle frame are provided. The guide rail 4 is injection molded separately, and the inner shuttle of the rotary shuttle is divided into two split inner shuttles, I5 and II6. The inner shuttles I5 and II6 are locked by two or more buckles and screws 7. The guide rail 4 is limited by the inner shuttles I5 and II.

[0090] The separate guide rail 4, with a planar structure in the shape of a washer or a snap ring, greatly simplifies the processing of the guide rail;

[0091] This application optimizes the guide rail from a single injection molding process to a separate part, which can be laid flat to cool after processing, reducing the risk of guide rail deformation and thus ensuring the flatness and cylindricity of the guide rail, greatly improving the pass rate of the guide rail.

[0092] Since polymer materials are injection molded at a certain high temperature, this will reduce the quality of the inner shuttle and increase the defect rate; however, the injection molding process of this application is completely unrelated to the inner shuttle, thus ensuring the quality of the inner shuttle and improving the overall quality of the rotary hook.

[0093] Furthermore, the oil-free rotary hook of this application allows for the replacement of the guide rail 4 during use, which is a significant advantage over existing oil-free rotary hooks.

[0094] In summary, this invention aims to solve the problems of complex injection molding, easy deformation, non-repairability, and difficulty in ensuring assembly accuracy of guide rails in existing oil-free rotary hooks. It proposes an oil-free rotary hook with a split inner hook and a detachable guide rail structure. By setting a limiting groove and a protruding mating structure between the inner hook I, inner hook II mating surfaces, and the guide rail, mechanical limiting positioning and integrated fixation of the guide rail and inner hook are achieved. This simplifies the manufacturing process, improves assembly accuracy, enhances structural stability, and extends service life, making it suitable for high-speed, high-reliability sewing equipment.

[0095] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present utility model, and these improvements and substitutions should also be considered within the protection scope of the present utility model.

Claims

1. An inner shuttle of an oil-free rotary shuttle, characterized in that, The inner shuttle consists of inner shuttle I (5) and inner shuttle II (6); The inner shuttle I (5) and inner shuttle II (6) are provided with groove I and / or protrusion I on their separate mating surfaces for fixing the guide rail (4) and the inner shuttle together. The groove I on inner shuttle I (5) or / and inner shuttle II (6) includes independent grooves and split grooves; The split groove is formed by the combination of inner shuttle I (5) and inner shuttle II (6) to form a combined groove for cavity extension and communication; An independent slot is a single cavity slot where the cavity is only located on inner shuttle I (5) or inner shuttle II (6).

2. The inner shuttle of an oil-free rotary shuttle as described in claim 1, characterized in that, The protrusion I on inner shuttle I (5) or / and inner shuttle II (6) includes independent protrusions and split protrusions; The separate protrusions are combined into an extended integrated protrusion by the combination of inner shuttle I (5) and inner shuttle II (6); An independent protrusion is a single protrusion that is only provided on inner shuttle I (5) or inner shuttle II (6).

3. The inner shuttle of an oil-free rotary shuttle as described in claim 2, characterized in that, The shape of the independent protrusion or / and the split protrusion is one or a combination of the shapes of a cylinder, a conical cylinder, an ellipsoid, a sphere, and a square cylinder, and the combined shape includes parts of at least two shapes.

4. The inner shuttle of an oil-free rotary shuttle as described in claim 1, characterized in that, The cavity shape of the independent groove or / and the split groove is any one of the following: cylindrical, semi-cylindrical, conical, semi-conical, semi-ellipsoidal, spherical, hemispherical or partially spherical.

5. The inner shuttle of an oil-free rotary shuttle as described in claim 4, characterized in that, The split-type groove is semi-circular in shape, and the independent groove is a dovetail groove.

6. The inner shuttle of an oil-free rotary shuttle as described in claim 1, characterized in that, Mounting holes are provided on inner shuttle I (5) and inner shuttle II (6), and inner shuttle I (5) and inner shuttle II (6) are fixed by screws (7).

7. A guide rail for an oil-free rotary shuttle, used in conjunction with the inner shuttle as described in any one of claims 1-6, characterized in that, The guide rail (4) is provided with a groove I and / or a protrusion I for limiting the guide rail (4) and the inner shuttle to be fixed together; Slot I, including independent slots and / or split slots; Protrusion I includes independent protrusions and / or separate protrusions, and the upper end face of protrusion I is aligned with the mating surfaces of inner shuttle I (5) and inner shuttle II (6).

8. The guide rail for an oil-free rotary hook as described in claim 7, characterized in that, The shape of the independent protrusion or / and the split protrusion is one or a combination of the shapes of a cylinder, a conical cylinder, an ellipsoid, a sphere, and a square cylinder, and the combined shape includes parts of at least two shapes.

9. The guide rail for an oil-free rotary hook as described in claim 7, characterized in that, The cavity shape of the independent groove or / and the split groove is any one of the following: cylindrical, semi-cylindrical, conical, semi-conical, semi-ellipsoidal, spherical, hemispherical or partially spherical.

10. An oil-free rotary shuttle, comprising an outer shuttle (1), a shuttle plate (2), and a shuttle skin (3), characterized in that, The outer shuttle (1), shuttle plate (2), and shuttle skin (3) are equipped with the inner shuttle as described in any one of claims 1-6; the guide rail (4) is provided with a groove I and / or a protrusion I, which are used to limit and connect the split joint surfaces of the inner shuttle I (5) and the inner shuttle II (6); the inner shuttle I (5) and the inner shuttle II (6) are fixed together by the groove I and / or the protrusion I of the guide rail (4).

Images