A pipe expanding and forming tool
The rolling extrusion forming tooling with shaft, mandrel, bushing and roller structure solves the problems of high cost and low versatility in the tube expansion forming process, and realizes efficient and stable forming and quality control of tube expansion.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 成都长之琳航空制造有限公司
- Filing Date
- 2025-08-19
- Publication Date
- 2026-07-31
AI Technical Summary
Existing tubing bulging forming tooling suffers from high cost, low versatility, poor forming quality, and poor stability. Furthermore, traditional tooling is difficult to adapt to the needs of tubing of different specifications and materials.
It adopts a shaft, mandrel, bushing and roller structure, and uses rolling extrusion forming method. Combined with CNC system to precisely control the expansion and contraction of the roller, it realizes flexible adjustment and precise control of the expansion of the guide tube.
It reduces tooling manufacturing costs, improves production economy and versatility, ensures consistent quality and forming stability of conduit expansion joints, and extends the service life of tooling.
Smart Images
Figure CN224574525U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of catheter technology, and in particular to a catheter expansion forming tool. Background Technology
[0002] In the construction of aircraft and engines, conduits and piping components play a crucial role. They are like the "blood vessels" of the airframe and engine, responsible for the transmission of various critical media such as air, fuel, and hydraulic oil. Their performance and condition are directly related to the stable and safe operation of the unit.
[0003] Currently, to meet the operational requirements of engines, bulging-formed guide tubes are widely used in engines. However, the tooling used in the manufacturing process of existing bulging-formed guide tubes has many problems:
[0004] First, when using the existing tooling to process bulging conduits, it is necessary to configure the corresponding bulging tooling for different bulging sizes, which undoubtedly increases the investment in tooling and results in higher economic costs.
[0005] Secondly, a single bulging tooling can often only be used to produce conduits of the same specification and material. The tooling has extremely poor versatility and low interchangeability. Not only does it require the stockpiling of a large number of different types of tooling, resulting in a waste of resources, but it is also extremely inconvenient during production switching, further reducing economic efficiency.
[0006] Furthermore, traditional bulging tooling uses a hard extrusion molding method, which achieves bulging of the conduit through sliding friction. This molding method has obvious defects: on the one hand, the molding quality is poor, which can easily lead to problems such as uneven wall thickness and surface damage in the conduit; on the other hand, the hard extrusion process generates a lot of heat, which not only affects the service life of the tooling, but may also have an adverse effect on the performance of the conduit material; at the same time, the entire molding process is difficult to control precisely and has poor stability, which seriously restricts the production quality and efficiency of bulged conduits. Utility Model Content
[0007] The purpose of this invention is to provide a catheter expansion and forming tool, which solves the above-mentioned problems.
[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a conduit expansion forming tool, including a shaft handle, a mandrel and a bushing, the mandrel is fixed at the end of the shaft handle, the bushing is provided on the outside of the mandrel, a through groove is provided inside the bushing, the bushing is fitted on the outside of the mandrel through the through groove, a groove is provided on the outer side wall of the bushing, and rollers are provided inside the groove.
[0009] Preferably, the size of the through groove is larger than the size of the mandrel, allowing the mandrel to move within the through groove.
[0010] Preferably, multiple grooves are provided, and the multiple grooves are equally spaced on the outer wall of the bushing.
[0011] Preferably, the groove body is connected to the interior of the through groove, the size of the groove body matches the size of the roller, and the roller can retract inward and expand outward in the groove body.
[0012] Preferably, a washer is provided at the rear end of the bushing, a retaining ring body is provided at one end of the washer, a second washer is provided at one end of the retaining ring body, and a shaft elastic retaining ring is provided at one end of the second washer.
[0013] Preferably, clearance holes are provided at the four corners inside the tank, and the clearance holes are symmetrical on both sides of the center line inside the tank.
[0014] Preferably, a baffle is provided at the front end of the mandrel, a fixing hole is provided inside the baffle, and a screw hole is provided at the front end inside the mandrel, with the fixing hole and the screw hole being aligned.
[0015] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0016] 1. This utility model provides a conduit bulging forming tooling. Through a gradient design where the outer diameter of the mandrel gradually increases from left to right, combined with the outward and inward expansion and contraction of the rollers within the groove, the outer diameter of the bushing can be flexibly adjusted, continuously changing from its minimum to its maximum state. This adjustability breaks the limitation of traditional tooling on bulging conduits of a single specification, and can adapt to the bulging needs of conduits with different diameter ranges. It eliminates the need to design dedicated tooling for each size, significantly reducing tooling manufacturing costs and inventory pressure, and substantially improving production economy.
[0017] 2. This utility model provides a conduit bulging forming tool. The core structure of the tool consists only of basic components such as a mandrel, bushing, roller, and baffle. The overall structure is simple and compact, and assembly and maintenance are convenient. Through a rolling extrusion forming method, it can adapt to the bulging processing of conduits of different materials (such as metal and plastic) of the same specification. Whether it is a rigid metal conduit or a plastic conduit with a certain degree of elasticity, the outward expansion force of the roller can be controlled by adjusting the pushing speed and distance of the mandrel, ensuring stable forming of conduits of different materials, demonstrating strong versatility and practicality.
[0018] 3. This utility model provides a conduit bulging forming fixture that replaces traditional sliding friction with rolling friction between rollers and the inner wall of the conduit. Combined with clearance holes to ensure the roller rotation accuracy (reducing interference from dust and foreign objects), the resistance during the forming process is significantly reduced, effectively avoiding defects such as cracking and wrinkling caused by excessive force on the conduit. Simultaneously, the fixture can be directly connected to a CNC conduit bulging machine. Parameters such as the mandrel's pushing distance and speed can be precisely controlled through the CNC system. Combined with the uniformity of roller expansion (the rollers rotate with the mandrel, ensuring uniform contact with all parts of the conduit's inner wall), precise control of key indicators such as bulging size and roundness is achieved, significantly improving the forming quality and consistency of the conduit bulging.
[0019] 4. This utility model provides a conduit expansion forming fixture. The baffle design prevents the mandrel from detaching from the bushing, avoiding accidental damage to the core component. The clearance hole eliminates the accumulation of foreign objects at the corners of the groove, reducing roller wear and jamming risks, and ensuring the long-term stability of the fixture. These detailed designs reduce equipment failure rate and maintenance frequency, further extending the service life of the fixture and indirectly improving production efficiency. Attached Figure Description
[0020] Figure 1 This is a schematic diagram of the overall structure of this utility model;
[0021] Figure 2 This is a front view structural diagram of the present utility model;
[0022] Figure 3 This is a front structural sectional view of the present invention;
[0023] Figure 4 This is a partial structural exploded view of the present invention;
[0024] Figure 5 This is a partial structural schematic diagram of the present invention.
[0025] The following are the annotations in the figure: 1. Shaft handle; 2. Mandrel; 3. Baffle; 31. Fixing hole; 32. Screw hole; 4. Shaft sleeve; 41. Groove; 42. Roller; 43. Washer 1; 431. Retaining ring body; 432. Washer 2; 433. Shaft elastic retaining ring; 44. Through groove; 45. Clearance hole. Detailed Implementation
[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0027] To further understand the content of this utility model, a detailed description of this utility model will be provided in conjunction with the accompanying drawings.
[0028] Combination Figures 1 to 5 As shown, a conduit expansion forming tool of the present invention includes a shaft handle 1, a mandrel 2 and a bushing 4. The mandrel 2 is fixed at the end of the shaft handle 1. The bushing 4 is provided on the outside of the mandrel 2. A through groove 44 is provided inside the bushing 4. The bushing 4 is fitted onto the outside of the mandrel 2 through the through groove 44. A groove 41 is provided on the outer side wall of the bushing 4. A roller 42 is provided inside the groove 41.
[0029] The size of the through groove 44 is larger than the size of the mandrel 2, and the mandrel 2 can move within the through groove 44.
[0030] Multiple grooves 41 are provided, and multiple grooves 41 are equally spaced on the outer side wall of the bushing 4.
[0031] The interior of the groove 41 is connected to the through groove 44. The size of the groove 41 matches the size of the roller 42, and the roller 42 can retract and expand within the groove 41.
[0032] The rear end of the bushing 4 is provided with a washer 43, one end of the washer 43 is provided with a retaining ring body 431, one end of the retaining ring body 431 is provided with a washer 432, and one end of the washer 432 is provided with a shaft elastic retaining ring 433.
[0033] The four corners inside the tank 41 are provided with clearance holes 45, which are symmetrical on both sides of the center line inside the tank 41.
[0034] The front end of the spindle 2 is provided with a baffle 3, the inside of the baffle 3 is provided with a fixing hole 31, and the front end of the spindle 2 is provided with a screw hole 32, with the fixing hole 31 and the screw hole 32 being directly opposite each other.
[0035] Working principle:
[0036] The baffle 3 is fixed by inserting an internal hexagonal head screw into the fixing hole 31 and screwing it into the screw hole 32. The baffle 3 is fixed to the front end of the spindle 2 by the screw. The baffle 3 can act as a barrier to prevent the spindle 2 from coming off the bushing 4, and the bushing 4 can rotate outside the spindle 2.
[0037] The structure of mandrel 2 has significant characteristics: Figure 3 For example, its outer diameter gradually increases from left to right, and this characteristic is the key basis for realizing the change of the outer diameter of the bushing 4.
[0038] When spindle 2 is located Figure 3When the position is shown, the outer wall of the mandrel 2 will push the roller 42 outward, causing the roller 42 to expand inside and outside the groove 41, thereby expanding the outer diameter of the bushing 4; when the front end of the shaft shank 1 is in close contact with the elastic retaining ring 433 of the shaft, the roller 42 reaches the maximum outward expansion position, at which time the outer diameter of the bushing 4 is at its maximum.
[0039] When the moving handle 1 causes the mandrel 2 to move from Figure 3 When the position shown moves to the right, the mandrel 2 gradually loses the outward pressure on the roller 42, and the roller 42 gradually retracts into the groove 41. The outer diameter of the bushing 4 shrinks due to the inward retraction of the roller 42. When the baffle 3 at the front end of the mandrel 2 is in close contact with the front end of the bushing 4, the outer diameter of the bushing 4 is at its minimum.
[0040] When performing catheter bulging, the operating steps are as follows: First, ensure that the baffle 3 at the front end of the mandrel 2 is tightly against the front end of the sleeve 4, so that the outer diameter of the sleeve 4 is at its minimum. At this time, place the portion of the catheter that needs to be bulged onto the outside of the sleeve 4. Then, gradually move the handle 1 to drive the mandrel 2 towards... Figure 3 The mandrel 2 is pushed to the left, and the outer wall of the mandrel 2 pushes the roller 42 to gradually expand outward in the groove 41. When the bushing 4 rotates, the roller 42 will rotate with it. During the rotation, the outwardly expanding roller 42 can continuously contact various parts of the inner wall of the conduit expansion port, thereby completing the conduit expansion operation.
[0041] Furthermore, the rollers 42 are placed inside the groove 41, while the clearance holes 45 are opened at the four corners inside the groove 41. Their function is to prevent dust and other contaminants from entering the corners of the groove 41 and thus avoid affecting the rotation of the rollers 42. The assembly relationship between the rollers 42 and the groove 41 is the core mating structure for realizing the adjustment of the outer diameter of the bushing 4: the rollers 42 need to flexibly complete the outward expansion and inward contraction movements within the groove 41, and their rotational accuracy directly affects the stability of the change in the outer diameter of the bushing 4. From the perspective of mechanical structure characteristics, the four corners inside the groove 41 are typical structural blind spots—because there is a 90-degree right-angle transition at the corners, when the rollers 42 roll or move within the groove 41, the corner area is difficult to be completely covered by the rollers 42, which easily forms a space for the accumulation of foreign objects such as dust and metal shavings.
[0042] The design of the clearance holes 45 located at the four corners inside the groove 41 is essentially to eliminate structural blind spots through the principle of space release: by increasing the space volume at the corners, the clearance holes 45 allow foreign objects that might otherwise accumulate at the corners to be naturally discharged or settled through the holes, avoiding the formation of hard accumulation. From a mechanical kinematics perspective, if foreign objects accumulate at the corners, it will cause unexpected gaps or sudden changes in frictional resistance between the roller 42 and the groove 41. When the roller 42 rolls to the vicinity of the corner, the foreign objects may cause local jamming, disrupting the continuity of the roller 42's movement, and consequently causing deviations in the adjustment of the outer diameter of the bushing 4.
[0043] In addition, the design also considers the retention efficiency of the lubricating medium: the clearance hole 45 can reduce the probability of lubricating oil accumulating at the corner due to surface tension and forming sludge, ensuring that the contact surface between the roller 42 and the groove 41 always maintains a good lubrication state, further reducing the risk of mechanical wear caused by foreign matter contamination, and ensuring the smooth rotation and long-term stability of the roller 42 from a structural perspective.
[0044] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.
[0045] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A pipe expanding tool comprising a shaft handle (1), a mandrel (2) and a sleeve (4), characterized in that: The end of the shaft (1) is fixed with a mandrel (2), and a bushing (4) is provided on the outside of the mandrel (2). A through groove (44) is provided inside the bushing (4). The bushing (4) is sleeved on the outside of the mandrel (2) through the through groove (44). A groove (41) is provided on the outer wall of the bushing (4), and a roller (42) is provided inside the groove (41).
2. The conduit flare forming tool of claim 1, wherein: The through groove (44) is larger than the mandrel (2), and the mandrel (2) is able to move within the through groove (44).
3. The conduit flare forming tool of claim 1, wherein: Multiple grooves (41) are provided, and multiple grooves (41) are equally spaced on the outer wall of the bushing (4).
4. The conduit flare forming tool of claim 1, wherein: The groove (41) is connected to the inside of the through groove (44). The size of the groove (41) matches the size of the roller (42). The roller (42) can retract and expand in the groove (41).
5. The conduit flare forming tool of claim 1, wherein: The bushing (4) has a washer (43) at its rear end, a retaining ring body (431) at one end of the washer (43), a washer (432) at one end of the retaining ring body (431), and a shaft elastic retaining ring (433) at one end of the washer (432).
6. The conduit flare forming tool of claim 1, wherein: The four corners inside the groove (41) are provided with clearance holes (45), which are symmetrical on both sides of the center line inside the groove (41).
7. The conduit flare forming tool of claim 1, wherein: The front end of the mandrel (2) is provided with a baffle (3), and a fixing hole (31) is provided inside the baffle (3). A screw hole (32) is provided inside the front end of the mandrel (2). The fixing hole (31) and the screw hole (32) are directly opposite each other.