Expanding reel for winding core tube type film capacitor
Patent Information
- Application Number
- CN202522366190.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-07
- Publication Date
- 2026-10-16
- Estimated Expiration
- 2035-11-07
AI Technical Summary
如果卷轴的外径不小于甚至略大于芯管的内径，则卷轴与芯管之间形成紧密、过盈或过渡配合，这种方案虽能确保卷绕初期的稳定性，但卷绕完成后，由于都是卷轴与芯管都是刚性的，几十上百层的金属化膜累积的径向张力将导致芯管与主轴产生“抱死”现象，这不仅造成卸料困难，更严重的是，在强行拆卸时，巨大的摩擦力与轴向力会破坏芯子端部金属化膜的层间结构，导致“抽芯”缺陷，该缺陷会直接损伤电极引出面，致使产品电性能失效，合格率降低
本实用新型通过设计相互配合的主轴、胀套、弹性圈、压簧、圆锥套和胀紧螺母，使用时将芯管套装在胀套外之后，可以通过旋转胀紧螺母使其推动圆锥套向靠近圆锥体的方向移动，利用圆锥套和圆锥体分别与胀套两端的圆锥孔配合，实现将胀套的外径增大即膨胀使其与芯管紧密配合的功能，从而能够确保在芯管上绕制金属化膜时卷绕初期的稳定性，绕制完成后反向旋转胀紧螺母，在压簧和弹性圈的作用下能够使胀套外径减小复位，从而能够在完工后轻松取下芯管，完成卸料，既提高了产品质量和合格率，又提高了卷绕效率，且便于操作。
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Figure CN224862142U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a reel for processing core tube type film capacitors, and more particularly to an expansion reel for winding core tube type film capacitors. Background Technology
[0002] Film capacitors, as key components in electronic circuits, are widely used in communications, home appliances, industrial control, and new energy fields due to their excellent frequency characteristics, high insulation resistance, and good stability. Core-tube film capacitors are a type of film capacitor in which a metallized film is wound onto a core tube. Before winding the metallized film, the core tube needs to be mounted on the spool of a winding machine.
[0003] The traditional spool for winding core-tube film capacitors is a main shaft with a fixed diameter and length. The process steps for winding core-tube film capacitors using this traditional spool are as follows: Feeding: Install the metallized film on the feed shaft of the winding machine, and at the same time load the core tube onto the winding machine's reel; Film application: The operator pulls the end of the metallized film and the insulating liner to the surface of the core tube, and then fixes its starting end to the core tube; Winding: The spool drives the core tube to rotate at high speed. During the rotation, the metallized film is unfolded and layered and wrapped around the core tube; two independent electrode leads are formed at the same time as winding. Finishing: After the preset number of turns or diameter is reached, cut the metallized film and use tape to temporarily fix the end of the metallized film to prevent the wound core from loosening. Unloading: Remove the core tube and metallized film from the reel to obtain the capacitor core; the capacitor core can be used directly as a core tube type film capacitor, or it can be fitted with a shell and other components to form a core tube type film capacitor.
[0004] The traditional method of using a reel to wind a thin-film capacitor has the following drawbacks: regardless of the design of the outer diameter of the reel and the inner diameter of the core tube, each has its own disadvantages, as detailed below: If the outer diameter of the spool is not less than or even slightly larger than the inner diameter of the core tube, a tight, interference, or transition fit will be formed between the spool and the core tube. Although this scheme can ensure the stability in the early stage of winding, after winding, since both the spool and the core tube are rigid, the radial tension accumulated by dozens or hundreds of metallized films will cause the core tube and the main shaft to "lock up". This not only makes unloading difficult, but more seriously, when forcibly disassembled, the huge friction and axial force will destroy the interlayer structure of the metallized film at the end of the core, resulting in a "core pulling" defect. This defect will directly damage the electrode lead-out surface, causing the product's electrical performance to fail and the pass rate to decrease.
[0005] If the outer diameter of the spool is smaller than the inner diameter of the core tube, a gap fit is formed between the spool and the core tube. Although this solution facilitates unloading at the end of the process, it will cause radial shaking of the core tube in the initial stage of winding. This shaking will destroy the tightness and uniformity of the initial stacking of the metallized film layers, resulting in a loose internal structure of the capacitor core and an increase in interlayer air gaps. These residual air gaps are prone to local ionization under the action of an electric field, which will significantly degrade the overall withstand voltage strength and long-term electrical reliability of the product, resulting in a lack of product quality assurance. Utility Model Content
[0006] The purpose of this invention is to provide an expansion-type reel for winding core tube film capacitors in order to solve the above problems. This reel can ensure stability in the initial winding stage and facilitate unloading upon completion.
[0007] This utility model achieves the above objectives through the following technical solutions: An expansion reel for winding a core-tube type film capacitor includes a main shaft, an expansion sleeve, an elastic ring, a compression spring, a conical sleeve, and a tightening nut. The main shaft has a cone-shaped section in its middle section that protrudes outwards and has a conical outer surface. One end of the main shaft has an external thread, and the tightening nut is fitted onto this end. The cylindrical expansion sleeve is formed by sequentially splicing multiple arc-shaped expansion sleeve blocks along the circumferential direction. The outer circumferential wall of the expansion sleeve has a groove, and the elastic ring is placed within this groove. Both ends of the central through hole of the expansion sleeve are conical holes, and the outer holes of these conical holes... The conical sleeve, with a diameter larger than the inner hole diameter and an outer wall surface that is conical, is fitted onto the outside of the main shaft through its central through hole and is located between the expansion nut and the cone. The expansion sleeve is fitted onto the outside of the main shaft and is located between the cone and the conical sleeve. The compression spring is fitted onto the outside of the main shaft and is located between the cone and the conical sleeve and is located inside the expansion sleeve. The outer conical surface of the cone and the corresponding conical hole wall of the expansion sleeve, and the outer conical surface of the conical sleeve and the corresponding conical hole wall of the expansion sleeve, can respectively make surface-to-surface contact.
[0008] Preferably, in order to better realize the expansion function of the expansion sleeve through the conical sleeve and the cone, the included angle between the outer conical surface of the cone and its axis, the included angle between the outer conical surface of the conical sleeve and its axis, and the included angle between the hole wall surfaces of the two conical holes and their axes are all 15-45°.
[0009] Preferably, in order to further and better realize the expansion function of the expansion sleeve through the conical sleeve and the cone, the included angle between the outer conical surface of the cone and its axis, the included angle between the outer conical surface of the conical sleeve and its axis, and the included angle between the hole wall surfaces of the two conical holes and their axes are all 30°.
[0010] Preferably, to facilitate the installation of the core tube, a retaining ring with a protrusion in the outward direction is provided on the outer circumference of one end of the expansion sleeve near the conical sleeve.
[0011] Preferably, to further facilitate the installation of the core tube, the expansion sleeve is provided with a clearance ring groove located inside the retaining ring.
[0012] Preferably, in order to facilitate reliable installation of the main shaft on the winding machine, the outer wall surfaces on opposite sides of the main shaft from the cone to the other end are provided with flat sections, and the flat sections are provided with bosses with an outer diameter larger than that of the main shaft near the cone.
[0013] Preferably, in order to more reliably realize the reset function after the expansion sleeve expands, the outer circumferential wall of the expansion sleeve is provided with two grooves arranged axially, and the two elastic rings are respectively placed in the two grooves.
[0014] Preferably, the tightening nut is a hand-tightening nut, which is convenient to tighten by hand.
[0015] Preferably, in order to more reliably drive the conical sleeve to move by the tightening nut, a washer fitted outside the main shaft is also provided between the conical sleeve and the tightening nut.
[0016] The beneficial effects of this utility model are as follows: This invention utilizes a design that integrates a main shaft, an expansion sleeve, an elastic ring, a compression spring, a conical sleeve, and a tightening nut. In use, after the core tube is fitted onto the expansion sleeve, rotating the tightening nut pushes the conical sleeve closer to the cone. The conical sleeve and cone engage with the conical holes at both ends of the expansion sleeve, increasing its outer diameter and ensuring a tight fit with the core tube. This ensures stability during the initial winding stage when the metallized film is wound onto the core tube. After winding, rotating the tightening nut in the opposite direction reduces the outer diameter of the expansion sleeve under the action of the compression spring and the elastic ring, allowing for easy removal of the core tube and unloading. This design improves product quality and yield, increases winding efficiency, and facilitates operation. Attached Figure Description
[0017] Figure 1 This is a front sectional view of the expansion-type reel assembly for the wound core tube type film capacitor described in this utility model. The compression spring in the figure is a non-sectional front view structure. Figure 2 This is a front view of the main shaft of the expansion-type reel for winding core tube type film capacitors according to this utility model; Figure 3 This is a front sectional view of the expansion sleeve of the expansion reel used for winding core tube type film capacitors according to this utility model. Detailed Implementation
[0018] The present invention will be further described below with reference to the accompanying drawings: like Figures 1-3 As shown, the expansion reel for winding a core-tube type film capacitor according to this utility model includes a main shaft 1, an expansion sleeve 5, an elastic ring 3 (which can be an elastic sealing ring), a compression spring 4, a conical sleeve 8, and a tightening nut 10. The middle section of the main shaft 1 has a cone 2 that protrudes outward in the circumferential direction and has a conical outer wall surface. One end of the main shaft 1 has an external thread 13 and the tightening nut 10 is fitted onto this end. The cylindrical expansion sleeve 5 is formed by sequentially splicing multiple arc-shaped expansion sleeve blocks (not individually marked in the figure, but easy to understand) along the circumferential direction. The outer circumferential wall of the expansion sleeve 5 has a groove 14 and the elastic ring 3 is placed in the groove 14. The center of the expansion sleeve 5 Both ends of the through hole 6 are conical holes 7, and the outer diameter of the conical hole 7 is larger than the inner diameter. The conical sleeve 8, whose outer wall surface is conical, is fitted onto the outside of the main shaft 1 through its own central through hole and is located between the expansion nut 10 and the cone 2. The expansion sleeve 5 is fitted onto the outside of the main shaft 1 through its own central through hole 6 and is located between the cone 2 and the conical sleeve 8. The compression spring 4 is fitted onto the outside of the main shaft 1 and is located between the cone 2 and the conical sleeve 8 and is located inside the expansion sleeve 5. The outer conical surface of the cone 2 and the corresponding conical hole 7 of the expansion sleeve 5, and the outer conical surface of the conical sleeve 8 and the corresponding conical hole 7 of the expansion sleeve 5 can respectively make surface contact.
[0019] like Figures 1-3 As shown, this utility model also discloses the following more optimized specific structures: In order to better realize the expansion function of the expansion sleeve 5 through the conical sleeve 8 and the conical body 2, the included angle between the outer conical surface of the conical body 2 and its axis, the included angle between the outer conical surface of the conical sleeve 8 and its axis, and the included angle between the hole wall surface of the two conical holes 7 and their axis are all 15-45°.
[0020] In order to further improve the expansion function of the expansion sleeve through the conical sleeve and the cone, the included angle between the outer conical surface of the cone 2 and its axis, the included angle between the outer conical surface of the conical sleeve 8 and its axis, and the included angle between the hole wall surface of the two conical holes 7 and their axis are all 30°.
[0021] To facilitate the installation of the core tube, a retaining ring 16 protruding outward is provided on the outer circumference of the expansion sleeve 5 near the conical sleeve 8.
[0022] To further facilitate the installation of the core tube, a clearance ring groove 15 is provided on the expansion sleeve 5 at the position inside the retaining ring 16.
[0023] To facilitate reliable installation of the main shaft 1 on the winding machine, the outer wall surfaces on both sides of the main shaft 1 from the cone 2 to the other end are provided with flat sections 11, and the flat sections 11 are provided with bosses 12 with an outer diameter larger than that of the main shaft 1 near the cone 2.
[0024] In order to more reliably realize the reset function after the expansion sleeve 5 expands, the outer circumferential wall of the expansion sleeve 5 is provided with two grooves 14 arranged axially, and the two elastic rings 3 are respectively placed in the two grooves 14.
[0025] To facilitate direct hand-tightening of the expansion nut 10, the expansion nut 10 is a hand-tightening nut.
[0026] In order to more reliably push the conical sleeve 8 to move via the expansion nut 10, a washer 9 fitted outside the main shaft 1 is also provided between the conical sleeve 8 and the expansion nut 10.
[0027] like Figures 1-3 As shown, in application, the main shaft 1 and the metallized film are first installed on the winding machine. Then, the core tube is fitted onto the expansion sleeve 5. Then, the expansion nut 10 is rotated to push the conical sleeve 8 and the expansion sleeve 5 towards the cone 2. The conical sleeve 8 and the cone 1 respectively engage with the conical surfaces of the conical holes 7 at both ends of the expansion sleeve 5 to increase the outer diameter of the expansion sleeve 5, i.e., to expand it so that it fits tightly with the core tube. Then, the end of the metallized film and the insulating liner are pulled to the surface of the core tube, and then its starting end is fixed on the core tube. The winding shaft drives the core tube to rotate at high speed. During the rotation, the metallized film is unfolded and layered and wound on the core tube until the winding process is completed. Then, the expansion nut 10 is rotated in the opposite direction. Under the action of the compression spring 4 and the elastic ring 3, the outer diameter of the expansion sleeve 5 can be reduced and reset. Thus, the core tube can be easily removed after completion, and the unloading is completed. Finally, the winding process is completed. The entire process not only ensures stability during the initial winding stage when the metallized film is wound on the core tube, but also allows for easy unloading, which improves product quality and yield, increases winding efficiency, and facilitates operation.
[0028] The above embodiments are merely preferred embodiments of this utility model and are not intended to limit the technical solutions of this utility model. Any technical solution that can be implemented based on the above embodiments without creative effort should be considered to fall within the scope of protection of this utility model patent.
Claims
1. An expansion reel for winding core-tube type thin film capacitors, comprising a main shaft, characterized in that: It also includes an expansion sleeve, an elastic ring, a compression spring, a conical sleeve, and a tightening nut. The middle section of the main shaft has a cone-shaped body that protrudes outwards and has a conical outer surface. One end of the main shaft has an external thread, and the tightening nut is fitted onto this end. The cylindrical expansion sleeve is composed of multiple arc-shaped expansion sleeve blocks sequentially spliced along the circumference. The outer circumferential wall of the expansion sleeve has a groove, and the elastic ring is placed within this groove. Both ends of the central through hole of the expansion sleeve are conical holes, with the outer diameter of the conical hole being larger than the inner diameter. The outer wall surface is... The conical sleeve of the conical surface is fitted onto the outside of the main shaft through its central through hole and is located between the expansion nut and the cone. The expansion sleeve is fitted onto the outside of the main shaft and is located between the cone and the conical sleeve. The compression spring is fitted onto the outside of the main shaft and is located between the cone and the conical sleeve and is located inside the expansion sleeve. The outer conical surface of the cone and the corresponding conical hole wall of the expansion sleeve, and the outer conical surface of the conical sleeve and the corresponding conical hole wall of the expansion sleeve can respectively make surface contact.
2. The expansion reel for winding a core-tube type thin film capacitor according to claim 1, characterized in that: The angle between the outer conical surface of the cone and its axial direction, the angle between the outer conical surface of the conical sleeve and its axial direction, and the angle between the wall surface of the two conical holes and their axial direction are all 15-45°.
3. The expansion reel for winding a core-tube type thin film capacitor according to claim 2, characterized in that: The angle between the outer conical surface of the cone and its axial direction, the angle between the outer conical surface of the conical sleeve and its axial direction, and the angle between the wall surface of the two conical holes and their axial direction are all 30°.
4. The expansion reel for winding a core-tube type film capacitor according to any one of claims 1-3, characterized in that: The expansion sleeve has a retaining ring that protrudes outward on the outer circumference of one end near the conical sleeve.
5. The expansion reel for winding a core-tube type thin film capacitor according to claim 4, characterized in that: The expansion sleeve is provided with a clearance ring groove located inside the retaining ring.
6. The expansion reel for winding a core-tube type thin-film capacitor according to any one of claims 1-3, characterized in that: The main shaft has flat sections formed by planes on the outer wall surfaces on opposite sides from the cone to the other end. The flat sections have bosses with an outer diameter larger than the main shaft near the cone.
7. The expansion reel for winding a core-tube type thin-film capacitor according to any one of claims 1-3, characterized in that: The outer circumferential wall of the expansion sleeve is provided with two grooves arranged axially, and the two elastic rings are respectively placed in the two grooves.
8. The expansion reel for winding a core-tube type thin-film capacitor according to any one of claims 1-3, characterized in that: The tightening nut is a hand-tightening nut.
9. The expansion reel for winding a core-tube type thin-film capacitor according to any one of claims 1-3, characterized in that: A washer fitted around the main shaft is also provided between the conical sleeve and the tightening nut.