Pipe bending and straightening tool for aircraft assembly
By designing a pipe bending and straightening tool suitable for aircraft oxygen systems, and utilizing pipe clamps and straightening roller sets for pipe bending, the problems of frequent tool changes and poor dimensional consistency are solved, achieving efficient and precise pipe bending operations and pipe protection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- AVIC CHENGFEI COMML AIRCRAFT COMPANY
- Filing Date
- 2026-05-15
- Publication Date
- 2026-06-12
AI Technical Summary
Existing aircraft oxygen system pipe bending technology suffers from problems such as frequent tool replacements, high costs, poor dimensional consistency, and easy damage to pipelines. Furthermore, traditional pipe bending tools have limited applicability.
A pipe bending and straightening tool was designed, comprising a base, a pipe fixing component, and a pipe bending and straightening component. The tool achieves pipe fixing and bending through a pipe clamp and a straightening roller assembly, and is equipped with radius scale markings and a protractor for precise adjustment, avoiding the use of additional forming molds.
It improves pipe bending efficiency and quality, reduces operational intensity and cost, ensures consistency of batch pipe bending and pipeline protection, is suitable for various specifications of pipelines, and meets the assembly requirements of aerospace precision pipelines.
Smart Images
Figure CN122184162A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of aircraft assembly technology, and in particular to a bending and straightening tool for aircraft assembly. Background Technology
[0002] Oxygen self-bending tubes are a crucial component of aircraft oxygen systems. Currently, they are primarily bent using a fixed-radius lever-type tube bender or manually. Both methods have drawbacks. Using a fixed-radius lever-type tube bender requires multiple sets of tools to handle different radii, necessitating frequent tool switching during on-site work. This increases carrying burden and construction costs, and also reduces bending efficiency. Manual bending, on the other hand, relies entirely on the operator's experience. Bending angles and radii lack parameterized markings, resulting in poor dimensional consistency in batches. Furthermore, the tubes come into direct contact with metal components, easily causing surface damage.
[0003] Chinese utility model patent CN217315274U discloses a multi-type aviation pipeline bender. Its technical solution includes a clamping base, with a first sleeve at the end of the clamping base. Inside the first sleeve, a first vertical shaft is rotatably mounted via a positioning sleeve. A rotating plate is connected to the outside of the positioning sleeve and above the sleeve via a second sleeve. A secondary wheel for bending the conduit is mounted on the rotating plate via a first adjustable device. A telescopic handle structure is fixed to the end face of the rotating plate. A fixing plate and a main wheel are sequentially fitted onto the upper part of the first vertical shaft. The fixing plate is fixedly connected to the clamping base via a fixing post. A blocking post for limiting the end of the conduit is mounted on the fixing plate via a second adjustable device. The technical solution of this utility model patent can be used to bend and shape different types of aircraft ducts. When bending the duct using the multi-type aviation pipe bender disclosed in this utility model, firstly, the bottom plate of the clamping base is clamped and fixed on the vise. According to the length of the duct and the bending position, the fixed installation position of the blocking post on the fixed plate is adjusted. After the adjustment is completed, the blocking post is effectively locked and fixed by the first locking handle. Then, the installation position of the auxiliary wheel is adjusted. After the adjustment is completed, the second positioning block is reliably locked and fixed by the second locking handle, thereby ensuring the reliable positioning of the auxiliary wheel. Then, the duct is placed between the blocking post, the main wheel and the auxiliary wheel. The rotating plate is manually turned. By rotating the telescopic handle, the rotating plate is driven. The auxiliary wheel is driven by the rotating plate, and the auxiliary wheel bends the duct around the main wheel to form the duct.
[0004] Chinese utility model patent CN213103928U discloses a novel adjustable-distance metal pipe bending device. Its technical solution includes a base, a pipe bending fixing shaft, a rolling shaft fixing seat, a rolling shaft, a handle, a pipe stop block, and a pipe pad. The bottom end of the pipe bending fixing shaft is fixedly mounted on the base, and a guide wheel is provided at the top. The middle part is connected to the rolling shaft fixing seat via a rolling bearing, allowing the rolling shaft fixing seat to rotate around the pipe bending fixing shaft. A groove is formed on the side of the rolling shaft fixing seat near the pipe bending fixing shaft, and the rolling shaft is disposed within the groove, parallel to the pipe bending fixing shaft. One end of the handle is fixedly connected to the rolling shaft fixing seat. The pipe pad is located on the same side of the pipe bending fixing shaft and the rolling shaft fixing seat. The pipe stop block is located on the side of the pipe pad, opposite to the pipe bending fixing shaft. One end of the pipe stop block is connected to the pipe pad via a pin, allowing the pipe stop block to rotate around the pin.
[0005] The aforementioned pipe bender is mainly used for bending hard metal pipes such as carbon steel pipes, stainless steel pipes, and aluminum pipes. During bending, one end of the metal pipe is fixed, and a forming mold is used to abut against the inner side of the bending part of the metal pipe. A force-applying component applies a large external force to the outer side of the bending part of the metal pipe to make it bend. The bending operation can only be achieved through the combined action of the forming mold and the force-applying component. Therefore, not only is a forming mold of a specific size required, but it is also not suitable for bending requirements of different angles. Summary of the Invention
[0006] The technical problem to be solved by the present invention is to provide a bending and straightening tool for aircraft assembly that is simple in structure, easy to operate, and has a wide range of applications.
[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: an aircraft assembly pipe bending and straightening tool, including a base, a pipe fixing assembly, and a pipe bending and straightening assembly; the pipe fixing assembly includes a pipe fixing guide rail fixed on the base and a pipe clamp slidably disposed on the pipe fixing guide rail; the pipe bending and straightening assembly includes a roller assembly fixing guide rail and a straightening roller assembly slidably disposed on the roller assembly fixing guide rail, one end of the roller assembly fixing guide rail is a movable end, and the other end of the roller assembly fixing guide rail is a hinged end that is hinged to the base, and the roller assembly fixing guide rail can rotate around one end of the pipe fixing guide rail; the straightening roller assembly includes two rollers spaced apart.
[0008] As an improvement to the above solution: the pipe clamp includes a first clamping part and a clamping part. The first clamping part is detachably installed on the pipe fixing guide rail by locking bolts. The clamping part is fixedly connected to the first clamping part, and the clamping part is provided with a pipe limiting hole.
[0009] As an improvement to the above solution: the clamping part includes two clamping halves arranged opposite each other and connected by locking screws. The opposite surfaces of the clamping halves are provided with clamping grooves, and the surface of the clamping grooves is fixedly provided with a first elastic layer.
[0010] As an improvement to the above solution: the fixed guide rail of the roller assembly is provided with a radius scale mark, which extends along the length of the fixed guide rail of the roller assembly with the hinge end as the starting point; the hinge end of the fixed guide rail of the roller assembly is provided with a protractor, and the center of the protractor is concentric with the rotation center of the fixed guide rail of the roller assembly.
[0011] As an improvement to the above solution: the orthopedic roller assembly further includes a second clamp and a mounting base. The second clamp is detachably mounted on the roller assembly fixed guide rail by locking bolts, and the mounting base is fixedly connected to the second clamp. The mounting base is provided with an adjustment groove, and the roller is movably mounted on the mounting base by an adjustment bolt that matches the adjustment groove.
[0012] As an improvement to the above solution: the roller is provided with an annular limiting groove on its circumferential surface, and a second elastic layer is fixedly provided on the surface of the annular limiting groove.
[0013] As an improvement to the above solution, the roller is rotatably mounted on the mounting base via bearings.
[0014] As an improvement to the above solution: a base connector is fixedly installed on the base. The base connector includes two clamping plates that are spaced apart and connected by bolts. The bottom of the clamping plates is bent and fixedly connected to the base by screws. Both ends of the pipeline fixing guide rail and the hinged end of the roller assembly fixing guide rail are clamped and fixed to the base by the base connector.
[0015] As an improvement to the above solution, a handle is provided at the movable end of the fixed guide rail of the roller assembly.
[0016] The beneficial effects of this invention are as follows: This invention clamps and fixes the pipe to be bent using a pipe fixing component, and applies uniform force to the inner and outer sides of the pipe using a straightening roller assembly in the pipe bending straightening component to achieve pipe bending. This invention can bend the pipe directly through the straightening roller assembly without the need for other additional forming molds. The lever structure effectively reduces the operator's workload, and the overall tool structure is simple, the pipe bending operation process is easy to implement, and it can effectively improve the efficiency of pipe bending operations. The roller assembly fixing guide rail in this invention can rotate relative to the pipe fixing guide rail, and both the pipe clamp and the straightening roller assembly can slide on the corresponding mounting guide rail, thereby allowing free adjustment of the pipe bending radius and bending angle. It is suitable for bending pipes of different specifications and can also ensure consistency during batch pipe bending, effectively improving the quality of pipe bending. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the structure of the present invention.
[0018] The markings in the diagram are: 100-base, 210-pipe fixing rail, 220-pipe clamp, 310-roller assembly fixing rail, 320-orthopedic roller assembly, 330-protractor, 340-handle, 400-base connector. Detailed Implementation
[0019] To facilitate understanding of the present invention, the invention will be further described below with reference to the accompanying drawings.
[0020] In the description of this invention, it should be noted that the terms "front", "rear", "left", "right", "up", "down", "inner", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of description, and do not indicate or imply that the device or component 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 of this invention.
[0021] like Figure 1As shown, the aircraft assembly pipe bending and straightening tool disclosed in this invention comprises a base 100, a pipe fixing assembly, and a pipe bending and straightening assembly. The base 100 is used to install the pipe fixing assembly and the pipe bending and straightening assembly, and serves as a support for the entire pipe bending and straightening tool, ensuring stability during pipe bending. The pipe fixing assembly is used to fix the pipe to be bent and straightened. The pipe bending and straightening assembly is used to bend the portion of the pipe to be straightened. The pipe fixing assembly includes a pipe fixing guide rail 210 fixed on the base 100 and a pipe clamp 220 slidably disposed on the pipe fixing guide rail 210. The pipe clamp 220 fixes the pipe to be bent and straightened, and the bending radius of the pipe can be adjusted by sliding the pipe clamp 220 on the pipe fixing guide rail 210. The pipe bending straightening assembly includes a roller assembly fixed guide rail 310 and a straightening roller assembly 320 slidably mounted on the roller assembly fixed guide rail 310. One end of the roller assembly fixed guide rail 310 is a movable end, and the other end is a hinged end hinged to the base 100. The roller assembly fixed guide rail 310 can rotate around one end of the pipe fixing guide rail 210. To facilitate operation of the roller assembly fixed guide rail 310, a handle 340 can be provided at the movable end of the roller assembly fixed guide rail 310. The straightening roller assembly 320 includes two rollers spaced apart. During pipe bending straightening, the pipe is passed between the two rollers, so that the part of the pipe to be straightened is in contact with the two rollers. The two spaced rollers of the straightening roller assembly 320 fix the part of the pipe to be bent. The bending angle of the pipe is adjusted by rotating the roller assembly fixed guide rail 310. The bending radius of the pipe can be adjusted by sliding the straightening roller assembly 320 on the roller assembly fixed guide rail 310. The two rollers of the straightening roller assembly 320 serve as the inner support mold and the outer pressure mold, respectively, applying uniform force to the inner and outer sides of the pipe. This avoids problems such as thinning, wrinkling or cracking of the inner side of the pipe due to uneven force, and can effectively improve the bending forming quality.
[0022] This invention achieves dual adjustment of the pipe bending radius by sliding the pipe clamp 220 on the pipe fixing guide rail 210 and the straightening roller assembly 320 on the roller assembly fixing guide rail 310. This effectively increases the adjustment range of the pipe bending radius. In addition to the basic adjustment of the distance between the straightening roller assembly 320 and the pipe clamp 220 by rotating the roller assembly fixing guide rail 310, the distance between the two can be further adjusted by sliding the straightening roller assembly 320 and the pipe clamp 220. This allows for a wider adjustment range of the pipe bending radius, breaking through the limitation of existing fixed radius pipe benders that do not have radius adjustment function. The bending radius can be adjusted within a width range of 5 to 50 cm. Therefore, there is no need to equip multiple sets of molds or independent tools, which can reduce tool procurement costs by at least 60%, thereby reducing the cost of pipe bending work.
[0023] like Figure 1 As shown, the pipe clamp 220 used in this invention includes a first clamping part and a clamping part. The first clamping part is detachably mounted on the pipe fixing guide rail 210 by a locking bolt. The clamping part is fixedly connected to the first clamping part, and the clamping part is provided with a pipe limiting hole. The clamping part includes two clamping halves arranged opposite to each other and connected by locking screws. The opposite surfaces of the clamping halves are provided with clamping grooves, and a first flexible layer is fixedly provided on the surface of the clamping grooves. The first flexible layer can be a flexible rubber layer with good elasticity. The first clamp part of this invention can be detachably installed on the pipeline fixing guide rail 210 by locking bolts, realizing the rapid sliding, positioning and locking of the pipeline clamp 220 on the pipeline fixing guide rail 210. It is easy to operate and can flexibly adjust the clamping position of the pipeline according to the target bending radius, ensuring that the starting point of the pipeline bending is accurately aligned with the center of the roller, providing a basic guarantee for the bending accuracy. The pipeline limiting hole set on the clamping part can perform axial and circumferential dual limiting of the pipeline, effectively preventing the pipeline from moving or shifting during the bending process, ensuring that the bending starting position of each pipeline is uniform when bending in batches, further improving the dimensional consistency of batch pipelines, reducing dimensional errors, meeting the assembly accuracy requirements of precision pipelines such as aircraft oxygen pipelines, and getting rid of the limitations of traditional manual bending that relies on experience positioning. Two opposing clamping halves are connected by locking screws to form an adjustable-space opening and closing structure, facilitating quick clamping and removal of pipelines. This design adapts to the clamping needs of pipelines of different diameters, meeting the bending requirements of various pipeline specifications without the need to change clamps, thus further enhancing tool versatility. Clamping grooves on the opposing surfaces of the clamping halves conform to the pipeline shape, enhancing clamping stability. A first flexible layer fixed to the groove surface isolates the metal clamping structure from the pipeline's outer wall, increasing clamping friction, preventing pipeline slippage, and effectively avoiding scratches and dents on the pipeline surface caused by rigid contact. It also prevents metal debris from falling into the pipeline and contaminating the internal medium, meeting the clean installation requirements of precision pipelines such as aviation oxygen pipelines, significantly improving the pipeline's appearance qualification rate.
[0024] To precisely adjust the angle and radius of the bend, this invention features a radius scale marking on the roller assembly fixed guide rail 310. This radius scale marking extends along the length of the roller assembly fixed guide rail 310, starting from the hinged end. Furthermore, a protractor 330 is installed at the hinged end of the roller assembly fixed guide rail 310, with its center concentric with the rotation center of the roller assembly fixed guide rail 310. By adding the radius scale marking and the protractor 330, this invention achieves precise control of the bend parameters, overcoming the shortcomings of existing technologies that lack parameterized markings and have insufficient precision. The radius scale marking on the roller assembly fixed guide rail 310, extending from the hinged end, allows for intuitive and accurate reading of the target bending radius. Combined with the guide rail sliding structure, this enables precise adjustment of the bending radius, achieving an adjustment accuracy of ±0.5cm, ensuring a precise match between the bending radius and the minimum allowable bending radius of the pipeline. The protractor 330, mounted on the hinged end of the guide rail 310 fixed by the roller assembly, can monitor the bending angle in real time, achieving an angle control accuracy of ±1°, thus enabling precise control of the bending angle. This invention, through dual parameter monitoring of the radius scale markings and the protractor 330, controls the dimensional error of batch pipework to ≤2%, far superior to the traditional manual bending error often exceeding 5%. It eliminates reliance on operator experience, reduces skills training costs, and simultaneously meets the stringent requirements for dimensional consistency in precision pipework during aircraft assembly. It also quantifies bending data, facilitating standardized mass production.
[0025] Furthermore, such as Figure 1As shown, the orthopedic roller assembly used in this invention also includes a second clamping part and a mounting base. The second clamping part is detachably mounted on the roller assembly fixing guide rail 310 by locking bolts, and the mounting base is fixedly connected to the second clamping part. The mounting base is provided with an adjustment groove, and the roller is movably mounted on the mounting base by an adjustment bolt that matches the adjustment groove. An annular limiting groove is provided on the circumferential surface of the roller, and a second flexible layer is fixedly provided on the surface of the annular limiting groove. The roller is rotatably mounted on the mounting base by bearings. This invention uses an annular limiting groove on the circumference of the roller to limit the pipe, effectively preventing lateral detachment or deviation during pipe bending, ensuring stable bending trajectory, and improving operational safety and forming quality. The second flexible layer fixed on the surface of the annular limiting groove can be made of medical-grade silicone material that is non-leaching and odorless, and complies with RoHS standards. This achieves flexible contact between the roller and the pipe, avoiding damage such as scratches and dents on the pipe surface caused by hard metal contact, increasing the pipe appearance qualification rate to 99%. At the same time, it can prevent metal debris from contaminating the inside of the pipe. In addition to being suitable for aviation oxygen pipelines, it can also meet the needs of food-grade pipelines, medical pipelines, and other scenarios with strict cleanliness requirements, thereby expanding the scope of application of the tool. The roller in this invention is rotatably mounted on the mounting base via bearings. During the bending process, the roller can roll synchronously and uniformly with the deformation of the pipe, transforming traditional sliding friction into rolling friction. On the one hand, this significantly reduces bending resistance and lowers the force load on the operator, making the bending operation more stable and smooth, facilitating control of the bending speed, and avoiding pipe forming deviations caused by force fluctuations. On the other hand, rolling friction can also effectively reduce the risk of scratching between the roller and the pipe surface, preventing scratches on the pipe surface, while ensuring that the force exerted by the roller on the pipe is uniform and stable, preventing local stress concentration that could lead to pipe stretching, thinning, wrinkling, or cracking. This is suitable for the non-destructive bending requirements of aerospace precision pipes such as TU1 oxygen-free copper pipes, improving the stability of bending forming quality.
[0026] like Figure 1As shown, a base connector 400 is fixedly mounted on the base 100 of the present invention. The base connector 400 includes two clamping plates spaced apart and connected by bolts. The bottom of the clamping plates is bent and fixedly connected to the base 100 by screws. Both ends of the pipeline fixing guide rail 210 and the hinge end of the roller assembly fixing guide rail 310 are clamped and fixed to the base 100 by the base connector 400. In this invention, two sets of base connectors 400 are used. The height of the base connector 400 that mates with the hinge end of the roller assembly fixing guide rail 310 is higher than the height of the other set of base connectors 400 to accommodate the installation requirements of the hinge end of the roller assembly fixing guide rail 310. This invention, by setting the base connector 400, can ensure the rigidity and stability of the overall tool structure, avoid deviations in bending radius and angle caused by component loosening or displacement during the bending process, and provide structural protection for bending accuracy. At the same time, the clamping plate structure of the base connector 400 is easy to assemble and disassemble, which facilitates the positioning, adjustment, maintenance and component replacement of the guide rail, improves the maintainability of the tool, adapts to the complex working environment of aircraft assembly site, ensures long-term stable operation of the tool, extends the tool's service life and reduces maintenance costs.
Claims
1. A pipe bending and straightening tool for aircraft assembly, characterized in that: The device includes a base (100), a pipe fixing assembly, and a pipe bending correction assembly. The pipe fixing assembly includes a pipe fixing guide rail (210) fixed on the base (100) and a pipe clamp (220) slidably disposed on the pipe fixing guide rail (210). The pipe bending correction assembly includes a roller assembly fixing guide rail (310) and a correction roller assembly (320) slidably disposed on the roller assembly fixing guide rail (310). One end of the roller assembly fixing guide rail (310) is a movable end, and the other end of the roller assembly fixing guide rail (310) is a hinged end that is hingedly connected to the base (100). The roller assembly fixing guide rail (310) can rotate around one end of the pipe fixing guide rail (210). The correction roller assembly (320) includes two rollers spaced apart.
2. The bending and straightening tool for aircraft assembly as described in claim 1, characterized in that: The pipe clamp (220) includes a first clamp part and a clamping part. The first clamp part is detachably installed on the pipe fixing guide rail (210) by locking bolts. The clamping part is fixedly connected to the first clamp part and the clamping part is provided with a pipe limiting hole.
3. The bending and straightening tool for aircraft assembly as described in claim 2, characterized in that: The clamping part includes two clamping halves arranged opposite each other and connected by locking screws. The opposite surfaces of the clamping halves are provided with clamping grooves, and a first flexible layer is fixedly provided on the surface of the clamping grooves.
4. The bending and straightening tool for aircraft assembly as described in claim 1, characterized in that: The roller assembly fixed guide rail (310) is provided with a radius scale mark, which extends along the length direction of the roller assembly fixed guide rail (310) with the hinge end as the starting point; the hinge end of the roller assembly fixed guide rail (310) is provided with a protractor (330), and the center of the protractor (330) is concentric with the rotation center of the roller assembly fixed guide rail (310).
5. The bending and straightening tool for aircraft assembly as described in claim 4, characterized in that: The orthopedic roller assembly also includes a second clamp and a mounting base. The second clamp is detachably mounted on the roller assembly fixed guide rail (310) by means of locking bolts. The mounting base is fixedly connected to the second clamp. The mounting base is provided with an adjustment groove. The roller is movably mounted on the mounting base by means of an adjustment bolt that matches the adjustment groove.
6. The bending and straightening tool for aircraft assembly as described in claim 4, characterized in that: The roller has an annular limiting groove on its circumference, and a second flexible layer is fixedly disposed on the surface of the annular limiting groove.
7. The bending and straightening tool for aircraft assembly as described in claim 4, characterized in that: The roller is rotatably mounted on the mounting base via bearings.
8. The bending and straightening tool for aircraft assembly as described in claim 1, characterized in that: A base connector (400) is fixedly installed on the base (100). The base connector (400) includes two clamping plates that are spaced apart and connected by bolts. The bottom of the clamping plates is bent and fixedly connected to the base (100) by screws. The two ends of the pipeline fixing guide rail (210) and the hinge end of the roller group fixing guide rail (310) are clamped and fixed on the base (100) by the base connector (400).
9. The bending and straightening tool for aircraft assembly as described in claim 1, characterized in that: The movable end of the roller assembly fixed guide rail (310) is provided with a handle (340).