Mechanical expanding and contracting shaft with round nut and spring ring

Abstract

The application discloses a mechanical expanding and contracting shaft for winding round nut spring ring, which is suitable for wide-to-narrow metal foil, high-end aluminum foil, electromagnetic foil, hand-tearing steel foil and solar film. In view of the problems of capsule air leakage, large radial runout of the shaft, low bending strength, small external expansion force, intermittent slipping between the winding drum and the tube and the like of the existing air bag and individual mechanical shaft, a novel structure expanding and contracting shaft composed of three mechanisms is provided. Under the action of the one-time rotation of the round nut and the secondary thrust amplification mechanism of the spring ring / tapered surface mechanism, a three-ton external expansion clamping force can be generated. After the external expansion of the winding drum and the tube, the gaps in the shaft can disappear automatically, so that the radial runout accuracy of the shaft is improved, and the bending resistance of the shaft in the suspended shaft drawing and the winding is improved. The shaft diameter adjusting mechanism before the expansion of the shaft can make the shaft be used in multiple ways. The cross pulling of the double-hook wrench can improve the external expansion force of the shaft by 50%. The shaft of the application is small in diameter and has no inflatable capsule, and can replace the shaft for thick and thin shearing machine.

Description

Technical Field

[0001] This invention relates to a mechanical expansion and contraction shaft with a round nut and spring ring, belonging to the tooling manufacturing field of roll winding shafts for metal foil, high-end electromagnetic foil, hand-tearable steel foil, solar film, and other roll materials. Background Technology

[0002] Large rolls of metal foil and non-metallic cloth or paper with large diameters and wide widths are wound up and cut into smaller rolls of different widths. The process involves threading a spool of the same width as the smaller roll onto a main shaft with its own clamping mechanism, tightening it, then unwinding and flattening it, attaching the face material to the spool, and completing the production process of narrowing the roll by rotating the shaft and cutting with blades.

[0003] The main technical requirements for the winding shaft are: the winding tubes must be tightly secured on the shaft without slipping; the radial runout of the shaft must be highly accurate; and the spacing between the winding tubes must be adjustable for convenient and quick operation.

[0004] The earliest method for widening and narrowing foil rolls used a mandrel that was operated by a hook wrench to move a round nut, which axially clamped the spool. The advantage of this method was high shaft strength. The main problem was that there was a clearance between the inner diameter of the spool and the outer diameter of the mandrel, resulting in low radial runout accuracy. Because it was axially clamped, adjusting the position of the spool relative to the centerline of the original roll required frequent disassembly of the spool ends and the round nut, which was time-consuming and labor-intensive. Furthermore, the user-required dimensions could not be cut to the desired dimensions on the spool end face.

[0005] Currently, the most commonly used shaft in the industry is the air-bag structure expansion shaft. Its main advantages are that, due to radial expansion, the spacing between the drum tubes is adjustable, no hook wrench is needed, and operation is convenient, making it popular with operators. The main problem is that... Figure 5 As shown, the reel tube 16 passes through a shaft surface with several long grooves. The clearance between the inner diameter of the reel tube 16 and the outer diameter of the mandrel is approximately 0.5-2 mm. The air bladder 18 and the rubber expansion strip 17 installed in the grooves are both elastic materials. The purpose of inflating the air bladder is to inflate the reel tube and prevent slippage. The reel tube and the mandrel do not form a rigid whole. Figure 5 As shown, in existing technologies, the larger the fit clearance 21, the greater the runout error. Supported by the compressed air and these elastic materials, the axis of the roll material is easily deviated from the axis of the expansion shaft under the influence of gravity and the asymmetrical external force of the flattening rollers within the equipment. This is especially true for heavy roll materials; during high-speed rotation and as the roll diameter gradually increases, the outer diameter of the roll will exhibit periodic, wave-like runout, and the end face of the roll will develop a serrated edge. The only solution to this problem is to reduce the machine speed. This issue is less noticeable when winding soft rolls of cloth and paper, but it significantly impacts production efficiency when winding high-end metal foil and hand-torn steel foil.

[0006] To address the large radial runout error of pneumatic expansion shafts and improve product quality, existing technology has improved the old-style 150mm diameter pneumatic expansion shaft. The method involves keeping the groove, pneumatic bladder, and expansion bar structure unchanged, but replacing the space occupied by the other five pneumatic bladders with a cylinder that pushes 84 graphite plates at a 12-degree inclination to precisely mechanically position the graphite plates on the winding tube. This improvement significantly enhances the shaft's runout accuracy, making it particularly suitable for winding small rolls of thin foil. However, the problems of insufficient expansion force and slippage during thick foil and wide-width rewinding remain unresolved.

[0007] Among existing domestic technologies, there are mechanical expansion shafts without air bladders, as disclosed in patent number 2006200306893, which describes a "high-precision coiling expansion shaft." Its advantage is a significantly improved external expansion force compared to air-bladder shafts. However, the internal fit clearance does not disappear automatically after the expansion sleeve is tightened, making it difficult to improve the radial runout accuracy of the shaft. Additionally, it suffers from drawbacks such as the expansion block not retracting automatically after expansion, difficulty in rewinding, and excessive number of turns required for the bevel gear nut.

[0008] like Figure 5 As shown, the design accuracy 19 and the measured accuracy 20 of the shaft in the prior art are actually not equal to each other and are "accuracy" without a common basis.

[0009] In existing technologies, especially for 75mm diameter air-cushioned expansion shafts, the milling of long grooves for installing air cushions presents a dilemma: high hardness, tool breakage, slow feed, and high processing costs. Therefore, 40mm carbon structural steel is often used for the mandrels, with high-quality alloy structural steel rarely chosen. Furthermore, some companies omit tempering during heat treatment, and even when it is done, the tensile strength is very low. Aside from the shaft ends, the material and tempering hardness are never clearly defined in the technical requirements. Starting from the smallest point of the groove cross-section—the bending point of the suspended coil—the straightness accuracy of the shaft deteriorates progressively during production. Investigations have shown that 75mm diameter air-cushioned expansion shafts longer than 2m cannot meet the quality requirements of high-end metal foil.

[0010] In response to the aforementioned defects of airbags and some mechanical expansion shafts, the inventor has invented a new type of "C-ring mechanical expansion shaft". It was granted an invention patent in 2014, patent number: ZL 2012 1 0269325.0. This patented shaft makes substantial improvements to the aforementioned expansion shafts with different structures. Its success lies in the significant enhancement of the external expansion force on the drum tube and a significant improvement in the shaft diameter runout accuracy. However, in several years of use, with the diversification of production, three main shortcomings have been identified that require improvement: (1) Due to the axial spacing problem of the exposed C-rings, long drum tubes can expand, but narrow ones cannot. (2) The milled keyways with radial asymmetry on the slender shaft affect the improvement of the shaft's straightness accuracy. (3) The screw connection pair 10 between the conical wedge tube 8 has a problem that the diameter of the bolt cylindrical head is small and the area of ​​the connecting groove is small. During frequent reciprocating pulling, the chain malfunctions, which affects the normal production.

[0011] Regarding the three defects of the patent ZL 2012 1 0269325.0, this invention not only thoroughly improves the aforementioned shaft, but also adds an innovative mechanism to the shaft that has never been seen before in other shafts. Summary of the Invention

[0012] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a mechanical expansion and contraction shaft with a round nut and spring ring to solve the above problems.

[0013] The mechanical expansion and contraction shaft with round nut and spring coil of the present invention includes a mandrel with a working end and a driving end fixed at both ends. The mandrel is provided with a pushing mechanism, an expansion and contraction mechanism and an expansion diameter adjustment mechanism in sequence. The pushing mechanism includes a round nut and a pushing tube at the left end. Rotation of the round nut can push the pushing tube to the right along the axis. The expansion diameter adjustment mechanism includes a starting push tube and an expansion diameter adjustment tube at the right end. Rotation of the expansion diameter adjustment tube can push the starting push tube to the left along the axis. Between the pushing mechanism and the expansion diameter adjustment mechanism is the expansion and contraction mechanism, which includes multiple spring expansion tubes with the same installation direction, multiple spring coils and an open tube installed on the outer diameter of the spring expansion tube. One end of the spring expansion tube has a conical surface and the other end has an end plane. The spring coils are installed between the conical surface and the end plane of adjacent spring expansion tubes. The open tube has an opening that runs through both ends.

[0014] The axial movement of the conical surface on the spring tube achieves the outward expansion of the spring coil and the open tube, thus completing the outward expansion of the roll tube. In use, the roll tube is threaded onto the open tube at the left end of the expansion shaft, and then the expansion shaft is clamped between the two shaft seats of the slitting machine. Based on the clearance between the roll tube and the open tube, the expansion diameter adjustment tube is turned to activate the pre-expansion shaft diameter adjustment mechanism, pushing the starting push tube and the spring expansion tube to the left, causing the spring coil and the open tube to initially expand outward, thereby adjusting the clearance between the roll tube and the open tube to a suitable level. According to the user's requirements, the spacing between the roll tubes is adjusted, and the hook wrench is used to turn the round nut, activating the push mechanism. The rotation of the round nut causes the push tube to move to the right on the shaft, which in turn moves the spring expansion tube to the right, causing the spring coil mounted on the conical surface to move radially under the obstruction of the adjacent end plane and expand outward with the open tube. High-speed rotation and seamless slitting ensure high-quality completion of the expansion shaft production task. After winding, the round nut is turned in the opposite direction. The push tube retracts, increasing the spring coil's own retraction ability. Combined with the opening of the cross-tube and the installation of several tension springs, the increased mechanical contraction force of the outer diameter further strengthens the contraction force during the insertion and winding of the open tube. Next comes the suspended winding of the shaft, a test of the shaft's bending resistance to ensure it can withstand prolonged use without bending.

[0015] The inner diameter of the round nut is threaded to the outer diameter of the mandrel. The inner diameter of the extension tube at the left end of the round nut mates with the working end shaft. The inner diameter of the extension tube at the right end is rotatably connected to the outer diameter of the push tube via a ring of steel balls. The inner diameter of the round nut and the outer diameter of the push tube are provided with annular grooves for releasing steel balls. The push tube is slidably mounted on the mandrel. The end of the push tube that connects to the spring expansion tube also has a conical surface. A spring coil is also installed between the conical surface of the push tube and the end face of the adjacent spring expansion tube. The inner diameter of the expansion diameter adjustment tube is threaded to the outer diameter of the starting push tube. The inner diameter of the expansion diameter adjustment tube is rotatably connected to the outer diameter of the mandrel via a ring of steel balls. The inner diameter of the expansion diameter adjustment tube and the outer diameter of the mandrel are provided with annular grooves for releasing steel balls. The starting push tube is slidably mounted on the mandrel. The end of the starting push tube that connects to the spring expansion tube also has an end face. A spring coil is also installed between the end face of the starting push tube and the conical surface of the adjacent spring expansion tube. Furthermore, guiding and limiting mechanisms are provided between the pushing tube and the spring expansion tube, between adjacent spring expansion tubes, and between the spring expansion tube and the starting push tube. Specifically, the guiding and limiting mechanisms are I-shaped tie rods; one end of the pushing tube has a sliding end T-groove, both ends of the spring expansion tube have a stationary end T-groove and a sliding end T-groove respectively, one end of the starting push tube has a stationary end T-groove, and both ends of the I-shaped tie rod are slidably disposed in the sliding end T-groove and fixedly disposed in the stationary end T-groove respectively. The pushing tube and the spring expansion tube, adjacent spring expansion tubes, and the spring expansion tube and the starting push tube are connected by the I-shaped tie rods. Adjacent tubes can be pushed or pulled by the I-shaped tie rods, and the sliding distance of the I-shaped tie rod in the sliding end T-groove is limited by the length of the sliding end T-groove.

[0016] The elastic tube extends from the conical end face ( Figure 2 Section 5.1) begins with a conical surface of 10-30 degrees. Figure 2 (5.2) A ring groove smaller than the length of the conical surface is provided, starting from the maximum outer diameter of the conical surface. Figure 2 (5.3) The wall thickness of the bottom of the annular groove is 1 / 2 to 1 / 8 of the wall thickness of the elastic tube. From the conical end face to the other side of the annular groove, the conical surface is divided into more than three equal parts, with an opening of 0.1 to 3 mm in width. A sliding end T-groove is provided at the point where the axis of the opening coincides with the opening. Figure 2 , Figure 3 (5.4 in the text), along the axis, from the end plane ( Figure 2 Section 5.6) also includes a stationary T-slot ( Figure 2 , Figure 3 5.5 in the middle), and starting from half the wall thickness, an inner ring platform is provided ( Figure 2 (5.7) The depth of the inner ring platform can accommodate and exceed the moving distance of the spring expansion tube. Under the obstruction of the end plane of the front spring expansion tube, the spring ring on the conical surface expands while being pushed along the machining accuracy of the conical surface by the conical surface. Under the limitation of the inner diameter of the drum tube and the thrust of the spring expansion tube, the rear spring ring quickly stops axially, just like the front spring ring, so that the coaxiality of the open tube is kept within a very high accuracy range.

[0017] The left end of the starting push tube has an end face similar to that of the spring tube and a stationary T-groove, and is connected to the sliding T-groove at the conical end face of the next spring tube via an I-shaped tie rod. The outer diameter of the open tube before expansion can be adjusted by rotating the expansion diameter adjustment tube. A round nut mounted on the threaded left end of the mandrel has several grooves on its outer diameter, similar to those on the working end shaft, for use with a hook wrench. The inner diameter of the extension tube at the left end of the round nut mates with the working end shaft, and the inner diameter of the extension tube at the right end is connected to the push tube via a ring of steel balls. The round nut and the push tube rotate relative to each other, allowing the push tube to move along the shaft. The right end of the push tube has a conical surface similar to that of the spring tube and a sliding T-groove, and is connected to the stationary T-groove at the conical end face of the next spring tube via an I-shaped tie rod. The I-shaped tie rod is installed in the T-shaped groove at the sliding end and stationary end between the two tubes through the opening of the spring coil. By axially moving the conical surface of the spring tube, the spring coil and the open tube expand and retract, thus achieving the production purpose of expanding and retracting the drum tube.

[0018] A positioning bolt is mounted on the mandrel. The end of the positioning bolt is installed in a threaded blind hole, and the head end passes through the open tube and mates with the open tube to position the open tube axially and circumferentially. A guide groove is provided on the spring-loaded tube through which the positioning bolt passes, and the positioning bolt is located within the guide groove. The length of the guide groove must be greater than the axial stroke of the spring-loaded tube. The number of spring-loaded tubes with guide grooves depends on the minimum width of the product roll and the length of the mandrel.

[0019] The spring coil has a circular or polygonal cross-section, and one side of the spring coil can be machined into a flat surface. The spring coil has an opening, and the distance between the openings is greater than the middle width of the I-shaped tie rod through which it passes. The cross-sectional diameter of the spring coil is equal to or less than the wall thickness of the expansion tube, and the outer diameter of the spring coil is equal to or less than the inner diameter of the opening tube. During installation, one flat surface of the spring coil should be close to the end plane of the expansion tube. The potential energy generated by the torsion and bending process of the spring coil gives it inherent elasticity of outward expansion and self-retraction. The spring coil steel wire is cold-drawn by a die, and its cross-sectional dimensional accuracy is extremely high over lengths of several thousand meters. After being bent into a spring coil, it acts as a connecting element between the mandrel tube and the opening tube, maximizing the coaxiality and radial runout accuracy of the shaft.

[0020] The I-shaped tie rod is symmetrical from left to right, and its thickness is equal to or less than the wall thickness of the spring tube, while its width in the middle is less than the opening spacing of the spring tube.

[0021] The shaft's expansion and contraction mechanism is equivalent to a typical inclined plane-to-inclined-plane force amplification combination. The difference is that its conical surface is equivalent to an inclined plane, but the opposite side of the conical surface is not an inclined plane but a circle—the cross-sectional circle of the spring coil. When used on a rotating shaft, this results in a small radial footprint, which is beneficial for increasing the cross-sectional area of ​​the spindle tube and improving the shaft's bending strength.

[0022] The total axial movement of the round nut is the sum of the strokes of each conical surface and the spring tube as it expands to the right and retracts to the left.

[0023] The formation of the spring ring / conical surface expansion accuracy: Spring expansion tubes are installed in the inner diameter of the open tube, with each spring expansion tube connected in series via an I-shaped tie rod. The expansion of the spring ring is achieved by pushing each tube in series until it reaches equilibrium and can no longer be pushed. The radial coaxiality and runout accuracy of the resulting shaft are mainly related to the machining accuracy of the spring ring / conical surface, and are independent of the magnitude of the thrust or the dimensional position to which the spring ring is pushed within the inner diameter of the open tube.

[0024] The inner diameter of the open tube is larger than the outer diameter of the spring tube assembly, while the outer diameter of the open tube is smaller than the minimum inner diameter of the reel tube. The length of the open tube is greater than the sum of the lengths of all the spring tubes connected in series. The outer diameter of the open tube has two or more through holes along the axial direction to mate with positioning bolts. Opposite to the through holes, there is an opening 1-5mm wide extending through both ends, with hook holes across the opening for mounting several tension springs. Positioned by one or more positioning bolts, the open tube mounted on the mandrel can only expand and contract radially, but cannot move or rotate axially. The outer diameter surface of the open tube has several V-shaped grooves 1-5mm wide and 0.2-2mm deep along the axial direction, which increases the clamping force on the reel tube, making it much more secure than the frictional tightening of the air spring shaft.

[0025] To enable open pipes to expand and contract: the maximum outer diameter of the open pipe should be smaller than the minimum inner diameter of the rolled pipe, and steel pipes with high elongation should be preferred.

[0026] To further enhance the shrinkage function of the open tube after expansion, several tension springs are installed at the hook holes on both sides of the opening of the open tube. The purpose is to add a set of long-lasting mechanical shrinkage forces to the open tube, so that the shrinkage function of the open tube will not weaken due to long-term and frequent expansion, and the increase in the outer diameter will not cause difficulties in threading and unwinding.

[0027] The purpose of installing two rings of steel balls on the shaft is to obtain a greater axial driving force and to minimize the friction when rotating the round nut and the expansion tube.

[0028] The two ends of the central thread of the round nut extend into tube ends that mate with the working end shaft and the outer diameter of the push tube. This facilitates the connection between the two ends of the round nut and enhances the overall bending resistance of the expansion shaft.

[0029] The main reason for using a hook wrench to turn the round nut is:

[0030] (1) Simple structure and convenient and quick operation. (2) The radial dimension of the round nut is small, which is conducive to increasing the cross-sectional area of ​​the mandrel and enhancing the bending resistance of the shaft. (3) Clamped to the end face, compared with the old-fashioned round nut shaft that requires disassembly of the round nut for each roll, the round nut of this patented shaft can be used for life without disassembly, which greatly improves work efficiency and reduces labor intensity. (4) With the shaft diameter adjustment mechanism before expansion, the number of turns of the round nut of this shaft can be controlled within 1 to 2 turns, and its operation time is shorter than the inflation time of the airbag expansion shaft. (5) If a hook wrench is used, the entire shaft will rotate with it during the hook rotation, so the increase in spiral force is affected. The other hook wrench hooks the shaft head at the working end, and the two hook wrenches are used to cross-turn, which can increase the mechanical external expansion force of the spring ring / conical surface by more than 50%.

[0031] Features of this invention:

[0032] (1) Add an open pipe through the outer diameter of the original C-ring assembly. This open pipe can only expand and contract radially, but cannot move axially or rotate radially. This ensures that the reels of different lengths can be tightly secured on the open pipe without slipping, and that the dimensions between the reels can also be adjusted.

[0033] (2) An open tube was added and the round head key of the original C-ring was removed. Since the long keyway was not machined on the slender shaft, the straightness accuracy of the shaft was improved.

[0034] (3) The original invention patent's "screw connection pair" was replaced with an I-shaped tie rod connecting the spring expansion tube assembly. One end of the tie rod, installed in the T-shaped groove at the stationary end of the spring expansion tube, is fixed along the shape, while the other end is installed on the I-shaped tie rod in the sliding end groove of the spring expansion tube, allowing for free axial sliding and continuous tensile resistance during frequent retraction. Based on patent ZL2012 1 0269325.0, the inventors improved upon the above three main defects. Furthermore, to reduce the shaft's manufacturing cost and enable multiple uses, a pre-expansion shaft diameter adjustment mechanism was added. A double-hook wrench was used to operate the shaft head and round nut, increasing the shaft's external expansion clamping force on the drum tube.

[0035] The beneficial effects of this invention compared to the prior art are:

[0036] 1. The spiral driving mechanism and the expansion and contraction mechanism of the shaft are integrated into one unit. The total external clamping force of the open tube on the reel tube can approach three tons or more. Compared with shafts in the prior art, the reel tube will not experience intermittent slippage, and there will be no quality impact on the surface tension of the foil due to unevenness of the folds. It can be used for both thin foil and thick foil cutting with a single shaft.

[0037] 2. The present invention has a shaft without an inflatable bladder. After the reel tube is expanded and tightened, as... Figure 6 As shown, the clearances at all points within shafts a, b, c, and d disappear spontaneously. The integration of metals, including the spool tube, into a single unit improves the shaft's runout accuracy and bending strength.

[0038] 3. The outer diameter of the shaft and the inner diameter of the bobbin in this invention are determined according to the requirements of the user's slitting machine. Although the differences are small, the dimensions vary. In existing technologies, the bobbin is threaded onto the shaft, and the fit clearance cannot be adjusted. Users can only adjust the fit clearance to improve product quality by replacing shafts with different diameters. This invention has a pre-expansion shaft diameter adjustment mechanism, which eliminates the need for users to replace shafts with different diameters, greatly improving production efficiency, ensuring product quality, reducing production costs, and saving working capital.

[0039] 4. In existing technologies using axial clamping with round nuts, adjusting the shaft's centerline relative to the original coil requires repeated disassembly and reassembly of the round nut and various tube ends of different lengths for each shaft used in production. This is time-consuming and labor-intensive, and the large number of tube ends prepared is detrimental to safe and efficient production in the workshop. Furthermore, the required relative dimensions between the coil end face and the spool tube end face cannot be machined. In contrast, the round nut in this invention does not require disassembly for its entire lifespan on the shaft. Combined with the pre-expansion shaft diameter adjustment mechanism, it reduces the number of times the operator needs to turn the nut, improving work efficiency and reducing labor intensity.

[0040] 5. The structural design, primarily based on lathe machining, pursues high precision and low cost. In machining, lathes offer high precision and efficiency for shaft-type workpieces. However, the machining of the grooves in the pneumatic expansion shaft is mainly done through milling, which not only reduces the effective cross-sectional area of ​​the shaft but also affects its strength. The design concept of this invention is to fully utilize and leverage the high precision and efficiency of lathe machining of rotating surfaces, combined with reprocessing using standard materials, thereby reducing the production cost of the shaft while simultaneously improving its coaxiality and radial runout accuracy.

[0041] 6. Compared to the 75mm diameter pneumatic expansion shaft, some argue that the use of a round nut structure is "outdated" and a "disadvantage." The applicant believes that the choice of tightening method should be based on efficiency. This invention's round nut / spring coil mechanical expansion shaft, at the bending point during suspended coiling, has a cross-sectional area and bending strength that are more than 40% larger than the pneumatic expansion shaft. Furthermore, it eliminates the need for frequent disassembly of the round nut and centering tube head; the number of turns of the nut can be controlled within 1-2 turns using the pre-expansion shaft diameter adjustment device. This reduces the operator's workload. The round nuts on every two expansion shafts have a positive and negative interlocking fit, tightening the nut with each turn. Since there is no air leakage, this is an advantage within the "disadvantages" of the round nut shaft.

[0042] 7. The expansion shaft of this invention can be equipped with two hook wrenches. For small diameter coils, one wrench is sufficient. For large, heavy coils and shafts requiring high speeds, two hook wrenches can be used to rotate the shaft in a cross manner, which can increase the clamping force by 50% compared to using only one hook wrench. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the overall structure of the shaft of the present invention;

[0044] Figure 2 This is a cross-sectional view of the elastic tube in the expansion shaft;

[0045] Figure 3 yes Figure 1 A schematic diagram of the shape and assembly of the E-shaped tie rod;

[0046] Figure 4 yes Figure 1 Schematic diagram of the installation of the tension spring on the open pipe in direction A;

[0047] Figure 5 This is a schematic diagram of the airbag inflation and contraction shaft in existing technology. The larger the fit clearance, the larger the runout error.

[0048] Figure 6 This invention provides a schematic diagram showing how the clearances at various points within shafts a, b, c, and d disappear automatically after the round nut is tightened.

[0049] In the diagram: 1. Working end shaft head; 2. Mandrel; 3. Round nut; 4. Push tube; 5. Spring expansion tube; 5.1. Conical end face; 5.2. Conical surface; 5.3. Annular groove; 5.4. Sliding end T-slot; 5.5. Stationary end T-slot; 5.6. End plane; 5.7. Inner ring platform; 6. Open tube; 7. Spring ring; 8. I-shaped tie rod; 9. Positioning bolt; 10. Guide groove; 11. Starting point push tube; 12. Expansion diameter adjustment tube; 13. Drive end shaft head; 14. Shaft head set screw; 15. Steel ball; 16. Drum tube; 17. Rubber expansion strip; 18. Inflatable bladder; 19. Shaft design accuracy; 20. Shaft actual measurement accuracy; 21. Fit clearance; 22. Tension spring; 23. Hook plate groove. Detailed Implementation

[0050] The present invention will be further described below with reference to specific embodiments. However, it should be noted that in the description of the present invention, terms such as "front end," "rear end," "left and right," "upper," "lower," and "horizontal," 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 the present invention and simplifying the description, and 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. Therefore, they should not be construed as limitations on the present invention. The accompanying drawings... Figure 1 This is the expansion shaft of the present invention. Before the outer expansion of the spool tube 16, the internal tubes of the shaft retract, the axial end face position is zero, and the starting position for outer expansion is shown in the diagram. It includes: a working end shaft head 1 and a transmission end shaft head 13, which are respectively fixed to the shaft platform at the left and right ends of the mandrel 2 by shaft head set screws 14. Three mechanisms are provided on the outer diameter of the mandrel 2. One mechanism is installed at the second shaft diameter of the left end of the mandrel 2, which consists of a round nut 3 pushing the tube 4 to form a helical pushing mechanism.

[0051] Starting from the left end of the inner diameter of the open pipe 6, the I-shaped tie rod 8 connects the push pipe 4, the spring expansion pipe 5 and the starting push pipe 11 to form a spring ring / conical expansion and contraction mechanism for the shaft.

[0052] The structural dimensions and technical requirements of the shaft ends of the expansion shaft are to be provided by the user. Due to differences in the type of rolled material, the model of the slitting equipment, and the structural dimensions of the main shaft clamping seat, the dimensions of the internal bevel and turning structure of the expansion shaft ends must be provided by the user. The requirement for the shaft manufacturer is that the internal bevels of the shaft ends serve as both machining and working references. For the drive-side shaft end 13, which mates with the mandrel 2, attention must be paid to improving the shaft's bending resistance.

[0053] The problem to be solved in designing the pre-expansion shaft diameter adjustment mechanism is as follows: In existing technology, taking aluminum foil winding as an example, the commonly used winding tube 16 for winding foil rolls has an inner diameter mainly of 75 ± 3 mm, corresponding to an outer diameter of 75 - 0.5 mm for the commonly used winding shaft. Thus, the maximum clearance between the shaft and the winding tube 16 is 3.5 mm. Based on the understanding that the larger the clearance, the greater the runout error, according to the understanding of airbags and other shafts, the radial runout clearance of 3.5 mm is far from the required runout error of 0.05 mm. To solve this problem, the practical approach is to machine several different outer diameter shafts with smaller clearances within the 3.5 mm range to match the winding tube 16, aiming to reduce the maximum clearance of 3.5 mm. This inevitably increases the number of shafts required for procurement.

[0054] The pre-expansion shaft diameter adjustment mechanism of the shaft in this invention adjusts the outer diameter of the expansion shaft so that the stroke of the spring expansion tube assembly does not exceed the maximum movement range of the guide groove 10, thereby minimizing the axial forward and backward stroke of the round nut 3 and improving the operating efficiency of the shaft.

[0055] The operation method of the shaft diameter adjustment mechanism before expansion and its positional relationship with the positioning bolts 9: In this initial position, it can be seen that two or more positioning bolts 9 are located in the middle of the guide groove 10 of the spring expansion tube 5. (According to the attached...) Figure 1 The method of use is as follows: If the fit clearance between the inner diameter of the reel tube 16 and the open tube 6 is too small, preventing it from reaching the outer diameter of the open tube 6, or if the thrust is too great after threading, the outer diameter of the open tube 6 should be reduced. This is done by rotating the expansion adjustment tube 12 to the left, causing the starting push tube 11 to pull the spring expansion tube assembly backward toward the right of the axis via the I-shaped pull rod 8. At this time, the outer diameter of the open tube 6 will retract, equivalent to the positioning bolt 9 reaching the left end face of the guide groove 10. Conversely, if the fit clearance between the open tube 6 and the reel tube 16 is too large, the outer diameter of the open tube 6 should be increased. This is done by rotating the expansion adjustment tube 12 to the right, causing the starting push tube 11 to push the spring expansion tube assembly forward toward the left end of the axis via the I-shaped pull rod 8. At this time, the outer diameter of the open tube 6 will expand outward, equivalent to the positioning bolt 9 reaching the right end face of the guide groove 10. The 16-inch reel tubes are all purchased in bulk. For each expansion shaft, it is not necessary to adjust the outer diameter of the shaft every time. The operator can adjust it to an intermediate size.

[0056] Installation sequence of the shaft's spring ring / conical expansion mechanism: as follows Figure 1As shown, starting from the right end of the mandrel 2, install the drive end shaft head 13 in the right end shaft diameter of the mandrel 2 and fix it with two or more shaft head set screws 14. After the expansion diameter adjustment tube 12 is threadedly engaged with the starting point push tube 11, insert the steel ball 15, tighten the sealing bolt, and install the two tubes together on the outer diameter of the right side of the mandrel 2. Then, starting from the left end of the mandrel 2, assemble the spring expansion tube 5, the push tube 4 and the spring ring 7 on its conical surface, and install them sequentially on the outer diameter of the mandrel 2.

[0057] like Figure 3 As shown in Figure E, an I-shaped tie rod 8 is installed between the two pipe fittings. The open tube 6 is threaded onto the outer diameter of the spring expansion tube 5 assembly. The positioning bolt 9 is fastened in the screw hole of the mandrel 2 through the guide groove 10 of the spring expansion tube 5 and the corresponding hole of the open tube 6, so as to restrict the open tube 6 to only expand and contract radially, and not to rotate circumferentially or move axially.

[0058] The calculation steps and formulas for the external expansion force of a round nut spring ring mechanical expansion shaft are as follows:

[0059] Based on the length L of the hook wrench and the F applied to the rotating handle end O By manipulating the lever force, one can calculate the magnitude of the first amplified external expansion force of the rotating screw (F) and the second amplified external expansion force of the spring coil / conical mechanical W.

[0060] (1). Calculate the force F that rotates the screw.

[0061] F = 2 × L / d × Fo

[0062] (2). Calculate the helical load after force F ----- W

[0063] Because: F = W × µ π d + t / πd - µ t

[0064] So: W = (π d - µ t / µ π d + t ) F

[0065] (3). Calculate the mechanical expansion force of the C-ring / inclined surface in the second stage ----- W_total

[0066] W_total = W / tg ( + a)

[0067] In the formula:

[0068] L ----- Length of hook wrench (cm)

[0069] a ----- Inclination angle of the inclined plane (cone)

[0070] d -----Effective diameter of the nut (cm)

[0071] T ----- Pitch (cm)

[0072] Fo ------ Hand lever force applied to the end of the crank handle

[0073] F ----- Load after helix

[0074] µ ----- The coefficient of friction is taken as 0.1

[0075] -----The friction angle is taken as tan 5°43'

[0076] The usage process or principle of this embodiment is as follows:

[0077] like Figure 1 The diagram shows the initial position of the round nut 3, spring ring 7, and mechanical expansion shaft before the reel tube 16 expands outward, with each tube inside the shaft retracted and ready to expand.

[0078] Starting from the working end shaft head 1 on the left side of the expansion shaft, thread the reel tube 16 onto the outer diameter of the open tube 6, and then suspend the expansion shaft between the two shaft seats on the slitting equipment. Clamp the shaft head in place using the positioning reference of the inclined surfaces at both ends of the shaft head.

[0079] Due to differences in processing units and batches, the inner diameter of the coiled tube 16 varies; not every coiled tube 16 has the same inner diameter. Based on the clearance between the coiled tube 16 and the open tube 6, the expansion diameter adjusting tube 12 is screwed on to adjust the axial position of the starting push tube 11. Changing the axial position of the spring expansion tube 5 and the conical surface 5.2 also alters the outer diameter of the spring ring 7 and the open tube 6. A smaller clearance is required to ensure smooth insertion and removal of the shaft.

[0080] Adjust the spacing between each roll tube 16 according to the user's requirements for the end face and end face dimensions of the roll and the spacing of the slitting blades.

[0081] Depending on the thickness, tension requirements, and diameter of the wound material, choose between one or two hook wrenches. For thin foil with a small diameter, one hook wrench is sufficient. For thick foil and large rolls, use two hook wrenches, rotating them in a crisscross pattern. This can increase the external expansion force of the spring coil / conical expansion mechanism by more than 50%. Hook wrenches and... Figure 1 The hook plate groove 23 is engaged. Turning the round nut 3 controls the axial movement of the spring-loaded tubes 5 and conical surface 5.2, one tube at a time, via the push tube 4. The spring ring 7 mounted on the conical surface pushes the open tube 6 radially to tighten the reel tube 16. After winding, turning the round nut 3 in the opposite direction causes the push tube 4 to retract. The spring ring 7's own contraction function, along with the contraction of the tension springs 22 across the open tube, causes the open tube 6 to retract automatically. Afterward, the tube is suspended and unwound, ready for the next winding cycle.

[0082] Of course, the above description is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the embodiments of the present invention. The present invention is also not limited to the above examples, and all equivalent changes and improvements made by those skilled in the art within the scope of the present invention should fall within the patent coverage of the present invention.

Claims

1. A mechanical expansion and contraction shaft for a round nut spring coil, comprising a spindle (2), a working end shaft head (1) fixed at the left end of the spindle (2) for a hook plate to be turned, and a driving end shaft head (13) provided at the right end, characterized in that: The spindle (2) is provided with a pushing mechanism, an expansion and contraction mechanism and an expansion shaft diameter adjustment mechanism in sequence. The pushing mechanism includes a round nut (3) at the left end and a pushing tube (4). The rotation of the round nut (3) can push the pushing tube (4) to the right along the axis. The pre-expansion shaft diameter adjustment mechanism includes a starting point push tube (11) at the right end and an expansion diameter adjustment tube (12). Rotating the expansion diameter adjustment tube (12) can push the starting point push tube (11) to the left along the axis. Between the pushing mechanism and the pre-expansion shaft diameter adjustment mechanism is an expansion and contraction mechanism. The expansion and contraction mechanism includes multiple spring expansion tubes (5) with the same installation direction, multiple spring rings (7) and an open tube (6) installed on the outer diameter of the spring expansion tube (5). One end of the spring expansion tube (5) has a conical surface and the other end has an end plane. The spring rings (7) are installed between the conical surface and the end plane of the adjacent spring expansion tubes (5). The open tube (6) has an opening (6.1) that runs through both ends.

2. The mechanical expansion and contraction shaft with round nut and spring ring according to claim 1, characterized in that: The inner diameter of the round nut (3) is connected to the outer diameter of the mandrel (2) by a thread. The inner diameter of the extension tube at the left end of the round nut (3) is matched with the working end shaft head (1). The inner diameter of the extension tube at the right end is rotatably connected to the outer diameter of the push tube (4) through a ring of steel balls (15). The push tube (4) is slidably set on the mandrel (2). The end of the push tube (4) that is connected to the spring expansion tube (5) also has a conical surface. A spring ring (7) is also installed between the conical surface of the push tube (4) and the end plane of the adjacent spring expansion tube (5).

3. The mechanical expansion and contraction shaft with round nut and spring ring according to claim 1 or 2, characterized in that: The inner diameter of the expansion adjustment tube (12) is connected to the outer diameter of the starting push tube (11) by a thread. The inner diameter of the expansion adjustment tube (12) is rotatably connected to the outer diameter of the mandrel (2) by a ring of steel balls (15). The starting push tube (11) is slidably set on the mandrel (2). The end of the starting push tube (11) connected to the spring expansion tube (5) also has an end plane. A spring ring (7) is also installed between the end plane of the starting push tube (11) and the conical surface of the adjacent spring expansion tube (5).

4. The mechanical expansion and contraction shaft with round nut and spring ring according to claim 3, characterized in that: Guiding and limiting mechanisms are provided between the push tube (4) and the spring expansion tube (5), between adjacent spring expansion tubes (5), and between the spring expansion tube (5) and the starting push tube (11).

5. The mechanical expansion and contraction shaft with round nut and spring ring according to claim 4, characterized in that: The guiding and limiting mechanism is an I-shaped tie rod (8); one end of the push tube (4) is provided with a sliding end T-shaped groove, the two ends of the spring expansion tube (5) are respectively provided with a stationary end T-shaped groove and a sliding end T-shaped groove, one end of the starting point push tube (11) is provided with a stationary end T-shaped groove, the two ends of the I-shaped tie rod (8) are respectively slidably arranged in the sliding end T-shaped groove and fixedly arranged in the stationary end T-shaped groove, and the push tube (4) and the spring expansion tube (5), the adjacent spring expansion tubes (5), and the spring expansion tube (5) and the starting point push tube (11) are connected by the I-shaped tie rod (8).

6. The mechanical expansion and contraction shaft with round nut and spring ring according to claim 4 or 5, characterized in that: A positioning bolt (9) is installed on the spindle (2). The end of the positioning bolt (9) is installed in the threaded blind hole, and the head end passes through the open tube (6) and cooperates with the open tube (6) to position the axial and radial positions of the open tube (6). A guide groove (10) is provided on the spring expansion tube (5) through which the positioning bolt (9) passes. The positioning bolt (9) is located in the guide groove (10). The length of the guide groove (10) is greater than the axial stroke of the spring expansion tube (5).

7. The mechanical expansion and contraction shaft with round nut and spring ring according to claim 3, characterized in that: The cross-section of the spring coil (7) is circular or polygonal. A flat surface is machined on one side of the spring coil (7). The spacing between the openings of the spring coil (7) is greater than the middle width of the I-shaped tie rod (8) through which it passes. The cross-sectional diameter of the spring coil (7) is equal to or less than the wall thickness of the expansion tube (5). The outer diameter of the spring coil (7) is equal to or less than the inner diameter of the opening tube (6).

8. The mechanical expansion and contraction shaft with round nut and spring ring according to claim 2, characterized in that: The outer diameter of the round nut (3) and the working end shaft (1) is provided with several hook plate grooves (23) for the hook plate to be turned by the hook plate.

9. The mechanical expansion and contraction shaft with round nut and spring ring according to claim 5, characterized in that: The I-shaped tie rod (8) is symmetrical from left to right, and its thickness is equal to or less than the wall thickness of the elastic tube (5).

10. The mechanical expansion and contraction shaft with round nut and spring ring according to claim 1, characterized in that: The length of the open tube (6) is greater than the sum of the lengths of all the spring tubes (5) connected in series; the outer diameter of the open tube (6) is provided with two or more through holes that cooperate with the positioning bolts (9) along the axial direction; opposite to the through holes, there is an opening (6.1) with a width of 1-5mm that runs through both ends axially; the outer diameter surface is provided with several axial V-grooves; and hook holes for installing several tension springs (22) are provided across the opening (6.1).

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