Trinity crimping stamping type integral fletching and crimping method thereof

Abstract

This invention relates to a three-in-one press-fit stamped integral dropper, comprising a dropper wire, upper and lower heart-shaped retaining rings, upper and lower press-fit tubes, upper and lower lifting rings, a catenary dropper wire clamp, a contact wire dropper wire clamp, and upper and lower press-fit terminals. The upper and lower heart-shaped retaining rings are respectively fitted onto the upper and lower lifting rings, which are respectively installed on the dropper wire clamps. One end of the dropper wire is wound around the upper heart-shaped retaining ring and connected to the upper press-fit terminal. The press-fit tube is pressed against the two parallel dropper wires near the opening of the heart-shaped retaining ring. The press-fit tube has three annular pressing grooves spaced apart. There is a gap between the two dropper wires inside the press-fit tube. The pressing force on the press-fit tube transitions evenly from large to small. The pressing method of this invention for the three-in-one press-fit stamped integral dropper simultaneously employs a longitudinal vertical pressing method, a transverse elliptical pressing method, and a segmented stepped pressing method for the press-fit tube of the dropper wire. This invention can avoid breakage of the suspension wire, loosening of bolts and wear cracks in the copper alloy lifting ring, and has high reliability, long service life and low operating cost.

Description

Technical Field

[0001] This invention relates to an electrified railway catenary erection device, specifically to a high-speed railway integral dropper. Background Technology

[0002] The function of the overall dropper is to suspend the contact wire evenly on the catenary cable to ensure that the contact wire is at the same height as the rail surface, so that the locomotive can smoothly and stably obtain current during high-speed movement.

[0003] The most commonly used component in existing high-speed rail overhead contact lines is the stamped integral dropper, which is an assembly that can transmit tension. The stamped integral dropper is connected to the contact wire and catenary cable as a whole by fastening bolts.

[0004] Practice has shown that stamped integral droppers are prone to failure in high-speed rail systems. Approximately 70% of these failures are due to the dropper wire breaking at the crimping tube outlet or the short connecting wire breaking at the crimping tube at the wire nose. Other causes include loosening of fastening bolts due to vibration, which, if not detected in time, can easily lead to nut detachment; and the copper alloy dropper eye is prone to cracking at the "U"-shaped tip.

[0005] To avoid pantograph-catenary faults and ensure the reliability of the high-speed railway catenary, a large amount of manpower and resources are invested in inspecting the entire dropper during operation, which increases operating costs.

[0006] Tests have shown that the main cause of the dropper wire breakage was an improper crimping method; the cause of bolt loosening was the lack of anti-loosening measures; and the cause of cracks in the copper alloy lifting eye was a deficiency in the original design. The specific causes and existing improvement measures are as follows:

[0007] 1. A dropper wire is a flexible, twisted wire with a single filament diameter of only 0.5mm. Its optimal working condition is to maintain overall stress during twisting. When the crimping method is improper, the dropper wire and the short connecting wire inside the crimped connector rub and squeeze against each other, causing the original filaments and strands to shift, resulting in unraveling and uneven filament and strand lengths. Under tension or repeated bending forces, the filaments and strands experience uneven stress. When the stressed filament or strand exceeds its limit (greater than its breaking strength), it will break. The tension then transfers to other filaments and strands, and this cycle repeats, leading to an increase in broken filaments or strands. When a certain critical point is reached, the entire wire will break. This is the main cause of dropper wire breakage.

[0008] Practice has proven that the key to extending the service life of the overall dropper wire lies in optimizing the crimping method. Initially, the high-speed rail overhead contact system used a three-point crimping method, which resulted in dropper wire breakage after 2 to 3 years of operation. A later improvement to a transverse elliptical crimping method delayed the breakage until 7 to 8 years. While improvements were made and effective, many problems arising after crimping remained unresolved. For example, issues such as friction between the two strands, unraveling, and inconsistent wire / strand lengths persisted.

[0009] 2. The reason for bolt loosening during operation is that the bolts, with their current machining precision, cannot meet the requirements of relatively severe contact wire vibration. Effective anti-loosening measures need to be taken to prevent bolt loosening from occurring.

[0010] 3. Stamped integral copper alloy lifting rings are prone to cracking at the "U"-shaped tip under severe contact wire vibration, indicating a design flaw. The machined lifting ring has direct contact between the "U"-shaped tip and the heart-shaped retaining ring. During vibration, dynamic pressure and dry friction occur at the contact point. Over time, this wears down the edge, reducing its strength. When this wear reaches a critical point, micro-cracks appear. Continued vibration causes these micro-cracks to gradually expand until fracture. The solution is to redesign a wear-resistant lifting ring to prevent friction.

[0011] In summary, there is an urgent need to develop a stamped integral dropper that can avoid dropper wire breakage, bolt loosening, and copper alloy eye cracking, and has high reliability, long service life, and low operating cost. Summary of the Invention

[0012] To address at least one of the three problems mentioned above—broken dropper wire, loose bolts, and cracked copper alloy eyelets—this invention provides a three-in-one press-fit stamped integral dropper.

[0013] This invention relates to a three-in-one press-fit stamped integral dropper, comprising a dropper wire, upper and lower heart-shaped retaining rings, upper and lower press-fit connectors, upper and lower lifting rings, a catenary dropper wire clamp, a contact wire dropper wire clamp, and upper and lower press-fit terminals. The upper and lower heart-shaped retaining rings are respectively fitted onto the upper and lower lifting rings. The upper lifting ring is installed on the catenary dropper wire clamp, and the lower lifting ring is installed on the contact wire dropper wire clamp. One end of the dropper wire is wound around the upper heart-shaped retaining ring and connected to the upper press-fit terminal. The upper press-fit connector is close to the end of the upper heart-shaped retaining ring and wraps around and presses tightly against the two folded dropper wires. The other end of the upper dropper wire is wrapped around the lower heart-shaped retaining ring and connected to the lower pressure terminal. The lower pressure connector is close to the end of the lower heart-shaped retaining ring and wrapped and pressed tightly on the two folded dropper wires. The upper and lower pressure connectors are provided with three annular pressure grooves at intervals. The width of the three annular pressure grooves of the upper pressure connector increases from the top to the bottom, and the width of the three annular pressure grooves of the lower pressure connector increases from the bottom to the top. There is a gap between the two dropper wires in the upper pressure connector and a gap between the two dropper wires in the lower pressure connector.

[0014] This invention relates to a three-in-one press-fit stamped integral dropper, wherein the upper dropper ring is installed on the catenary dropper clamp by an upper fastening bolt. Both ends of the upper fastening bolt are respectively fitted with an upper stop washer 1 and an upper stop washer 2. The upper stop washer is stamped from a 1.5mm thick stainless steel plate. The upper stop washer 1 includes an upper collar 1, four rectangular upper baffles 1 integrally formed with the upper collar 1 and perpendicular to the plane of the upper collar 1, and two L-shaped upper claws. First, four upper rectangular baffles are tightly attached to the hexagonal nuts of the upper fastening bolts, and two upper claws are respectively located at both ends of the upper collar and engaged with the catenary cable hanger wire clamp; the upper stop washer includes an upper collar and a rectangular upper baffle that is integrally formed with the upper collar and perpendicular to the plane of the upper collar, and two L-shaped upper claws. The rectangular upper baffles are tightly attached to the nuts of the upper fastening bolts, and the two upper claws are respectively located at both ends of the upper collar and engaged with the catenary cable hanger wire clamp.

[0015] This invention relates to a three-in-one press-fit stamped integral dropper, wherein the lower dropper ring is installed on the contact wire dropper clamp by a lower fastening bolt. Both ends of the lower fastening bolt are fitted with a lower stop washer 1 and a lower stop washer 2. Both lower stop washer 1 and lower stop washer 2 are stamped from stainless steel plates with a thickness of 1.5mm. The lower stop washer 1 includes a lower collar 1 and four rectangular lower baffles 1 integrally formed with the lower collar 1 and perpendicular to the plane of the lower collar 1, and two L-shaped... The lower retaining pad consists of a lower retaining ring and four rectangular lower baffles that are tightly attached to the hexagonal nut of the lower fastening bolt. Two lower retaining pads are located at both ends of the lower retaining ring and are engaged with the contact wire dropper clamp. The lower stop washer includes a lower retaining ring and two rectangular lower baffles that are integrally formed with the lower retaining ring and are perpendicular to the plane of the lower retaining ring. The rectangular lower baffles are tightly attached to the nut of the lower fastening bolt. The two lower retaining pads are located at both ends of the lower retaining ring and are engaged with the contact wire dropper clamp.

[0016] This invention relates to a three-in-one press-fit stamped integral dropper, wherein the lower dropper ring is installed on the contact wire dropper clamp by a lower fastening bolt, and both ends of the lower fastening bolt are fitted with lower stop washers. The lower stop washers are stamped from 2mm thick stainless steel plates and include hexagonal pieces that are identical in shape to the nut of the lower fastening bolt and are in close contact with the hexagonal cap of the lower fastening bolt and the six upright sides of the nut.

[0017] The present invention relates to a three-in-one press-fit stamped integral suspension string, wherein the edge of the upper suspension ring is provided with a flange, and the angle of the flange is 90°.

[0018] The present invention relates to a three-in-one press-fit stamped integral dropper, wherein the thickness of the first flange is 2mm.

[0019] The present invention relates to a three-in-one press-fit stamped integral suspension string, wherein the lower suspension ring has a second flange on its edge, and the angle of the second flange is 90°.

[0020] The present invention relates to a three-in-one press-fit stamped integral dropper, wherein the thickness of the second flange is 2mm.

[0021] The present invention relates to a three-in-one press-fit stamped integral suspension string, wherein the lower suspension ring has two flanges on its edge, each flange having an angle of 90°, and the two flanges are arranged to be turned inwards towards each other.

[0022] The present invention relates to a three-in-one press-fit stamped integral dropper, wherein the thickness of the second flange is 2mm.

[0023] The present invention relates to a three-in-one press-fit stamped integral suspension string, wherein the upper suspension ring has two flanges at the U-shaped top end that are inclined at 5 degrees to the inward side.

[0024] The present invention relates to a three-in-one press-fit stamped integral suspension string, wherein the U-shaped top of the lower suspension ring and the two flanges are inclined at 5 degrees to the inner sides in opposite directions.

[0025] The present invention relates to a three-in-one press-fit stamped integral dropper, wherein the load-bearing cable dropper clamp and the contact wire dropper clamp are both made of copper alloy plate with a thickness of 3mm by stamping.

[0026] The difference between this invention and existing technologies lies in the fact that, in this invention, the crimping force on the upper crimping tube transitions uniformly from large to small from top to bottom, and the crimping force on the lower crimping tube transitions uniformly from large to small from bottom to top. This ensures that the dropper wire is stressed as a whole, without disrupting its original twisted state, preventing strand breakage, and avoiding uneven strand lengths. This achieves the optimal stress state for the flexible dropper wire, preventing breakage. Simultaneously, both the upper and lower dropper rings employ a flanged design and a 5-degree inward tilt to prevent breakage at the tip of the copper alloy dropper ring. Furthermore, upper and lower locking washers are installed on the upper and lower fastening bolts to effectively prevent bolt loosening. This invention's integral dropper wire offers advantages such as high reliability, long service life, and low operating costs.

[0027] The present invention discloses a three-in-one press-fitting method for integral droppers, which simultaneously employs a longitudinal vertical press-fitting method, a transverse elliptical press-fitting method, and a segmented stepped press-fitting method for the upper and lower press-fitting pipes.

[0028] The present invention discloses a three-in-one press-fit stamping method for integral droppers, comprising the following steps:

[0029] Step 1: Press the upper pressure tube vertically along the vertical center line of the upper pressure tube surface of the ellipse, so that the two suspension wire strands inside the upper pressure tube are separated by a small gap, and the two suspension wire strands being pressed together maintain a circular shape.

[0030] Step 2: Based on Step 1, press the upper pressing pipe after Step 1 into a horizontal elliptical shape;

[0031] Step 3: Based on Step 2, divide the crimping pipe into three sections and use different crimping forces to crimp the upper crimping pipe after Step 2 in three sections. The crimping force increases sequentially from the lower end to the upper end of the upper crimping pipe in three sections.

[0032] Step 4: Repeat steps 1 to 3 to complete the crimping of the lower pressure pipe; when using different crimping forces to press the lower pressure pipe in stages, the crimping force increases sequentially in three stages from the upper end to the lower end of the lower pressure pipe.

[0033] The difference between this invention and the prior art is that this invention adopts a three-in-one crimping method, which ensures that the crimped dropper wire can be stressed as a whole without destroying the original twisted state, without unraveling the strands, and without the phenomenon of uneven lengths of the strands, thereby achieving the optimal stress state of the flexible dropper wire and preventing the dropper wire from breaking.

[0034] The dropper wire obtained by the crimping method of this invention has high overall reliability, long service life and low operating cost.

[0035] The invention will now be further described with reference to the accompanying drawings. Attached Figure Description

[0036] Figure 1 This is a perspective view of the present invention;

[0037] Figure 2 This is the front view of the present invention;

[0038] Figure 3 This is the left view of the present invention;

[0039] Figure 4 for Figure 1 A three-dimensional view of the upper and lower locking washers;

[0040] Figure 5 This is a top view of the upper and lower stop shims;

[0041] Figure 6 This is the front view of the upper and lower stop shims;

[0042] Figure 7 This is a left view of the upper and lower stop shims.

[0043] Figure 8 for Figure 1 A three-dimensional view of the upper and lower locking washers 2;

[0044] Figure 9 This is a top view of the upper and lower stop shims 2;

[0045] Figure 10 This is the front view of the upper and lower stop shims 2;

[0046] Figure 11 This is the left view of the upper and lower stop shims. Detailed Implementation

[0047] like Figure 1-3 As shown, the three-in-one press-fit stamped integral dropper of the present invention includes a dropper wire 11, an upper heart-shaped retaining ring 12, a lower heart-shaped retaining ring 12', an upper press-fit connector 13, a lower press-fit connector 13', an upper dropper ring 14, a lower dropper ring 14, a catenary dropper wire clamp 15, a contact wire dropper wire clamp 1, an upper press-fit terminal 111, and a lower press-fit terminal 111'. The upper heart-shaped retaining ring 12 is fitted onto the upper dropper ring 14, and the lower heart-shaped retaining ring 12' is fitted onto the lower dropper ring 14'. The upper dropper ring 14 is installed on the catenary dropper wire clamp 15, and the lower dropper ring 14' is installed on the contact wire dropper wire clamp 1. One end of the dropper wire 11 is wound around the upper heart-shaped retaining ring 12 and connected to the upper press-fit terminal 111'. The connector 111 is connected, the upper pressure connector 13 is close to the end of the upper heart-shaped retaining ring 12 and is sleeved on the two folded drop strings 11. The other end of the drop string 11 is wrapped around the lower heart-shaped retaining ring 12' and connected to the lower pressure connector 111'. The lower pressure connector 13' is close to the end of the lower heart-shaped retaining ring 12' and is sleeved on the two folded drop strings 11. The upper pressure connector 13 is provided with three annular pressure grooves 131 at intervals. The pressing force on the upper pressure connector 13 decreases from the upper end to the lower end. The width of the three annular pressure grooves 131 increases from the upper end to the lower end. There is a gap between the two drop strings inside the upper pressure connector 13. The lower pressure connector 13' has three annular pressure grooves 131' spaced apart. The pressing force on the lower pressure connector 13' decreases sequentially from the bottom to the top, and the width of the three annular pressure grooves 131' increases sequentially from the bottom to the top. A gap is left between the two dropper wires inside the lower pressure connector 13'. This gap is to prevent the two dropper wires from rubbing against each other.

[0048] The annular pressure groove 131 has an elliptical cross-sectional shape, the dropper 11 is cylindrical, and the spacing between two adjacent annular pressure grooves 131 is reserved for the elongation area of ​​the dropper after crimping. Both ends of the upper pressure connector 13 are flared outwards to reduce the mutual friction between the dropper 11 and the upper pressure connector 13 at the outlet of the upper pressure connector 13. The spacing between two adjacent annular pressure grooves 131' is also reserved for the elongation area of ​​the dropper after crimping, and both ends of the lower pressure connector 13' are flared outwards 132' to reduce the mutual friction between the dropper 11 and the lower pressure connector 13' at the outlet of the lower pressure connector 13'.

[0049] like Figure 1 , 4 As shown in Figure 7, the upper lifting ring 14 is installed on the catenary suspension wire clamp 15 by the upper fastening bolt 16. To prevent loosening, the head of the upper fastening bolt 16 is fitted with an upper stop washer 17, and the nut end of the upper fastening bolt is fitted with an upper stop washer 28. Both the upper stop washer 17 and the upper stop washer 28 are stamped from 1.5mm thick stainless steel plates. The upper stop washer 17 includes an upper collar 171 and four rectangular upper baffles 172 and two L-shaped upper claws 173 that are integrally formed with the upper collar 171 and perpendicular to the plane of the upper collar 171. The four upper rectangular baffles 172 are close to the hexagonal nuts of the upper fastening bolt 16, and the two upper claws 173 are located at both ends of the upper collar 171 and are engaged with the catenary suspension wire clamp 15.

[0050] like Figure 1-3 As shown in Figure 8-11, the upper stop washer 18 includes an upper collar 181, a rectangular upper baffle 182 that is integrally formed with the upper collar 181 and perpendicular to the plane of the upper collar 181, and two L-shaped upper claws 183. The rectangular upper baffle 182 is tightly attached to the nut of the upper fastening bolt 16, and the two upper claws 183 are located at both ends of the upper collar 18 and are engaged with the catenary cable hanger clamp 1.

[0051] like Figure 1-3 As shown, the lower lifting ring 14' is installed on the contact wire suspension clamp 1 by the lower fastening bolt 16'. To prevent loosening, the two ends of the lower fastening bolt 16' are fitted with lower stop washer 17' and lower stop washer 18'. Both lower stop washer 17' and lower stop washer 18' are stamped from stainless steel plates with a thickness of 1.5mm.

[0052] The structure of the lower stop washer 17' is the same as that of the upper stop washer 17. As shown in 1-3 and 4-7, the lower stop washer 17' includes a lower collar 171' and four rectangular lower baffles 172' that are integrally formed with the lower collar 171' and perpendicular to the plane of the lower collar 1, and two L-shaped lower claws 173'. The four rectangular lower baffles 172' are close to the hexagonal nuts of the lower fastening bolt 16', and the two lower claws 173' are located at both ends of the lower collar 1 and are engaged with the contact wire dropper clamp 1.

[0053] The structure of the lower stop washer 18' is the same as that of the upper stop washer 18. As shown in 1-3 and 8-11, the lower stop washer 18' includes a lower collar 181', a rectangular lower baffle 182' that is integrally formed with the lower collar 181' and perpendicular to the plane of the lower collar 181', and two L-shaped lower claws 183'. The rectangular lower baffle 182' is close to the nut of the lower fastening bolt 16', and the two lower claws 183' are located at both ends of the lower collar 181' and are engaged with the contact wire dropper clamp 1.

[0054] like Figure 1 As shown, the upper lifting ring 14 has a flange 141 on its edge. The flange 141 has an angle of 90° and a thickness of 2mm. The two flanges 141 are turned inwards towards each other. At the U-shaped top of the upper lifting ring 14, the two flanges 141 are tilted inwards at an angle of 5 degrees. This design increases the gap between the U-shaped upper lifting ring 14 and the upper heart-shaped guard ring 12, preventing direct contact and friction between the two during vibration.

[0055] like Figure 1 As shown, the lower lifting ring 14' has two flanges 141' on its edge, each flange 141' having an angle of 90° and a thickness of 2mm. The two flanges 141' are set to bevel inwards towards each other. At the U-shaped top of the lower lifting ring 14', the two flanges 141' are set to be inclined inwards at 5 degrees towards each other. This arrangement increases the gap between the U-shaped lower lifting ring 14' and the lower heart-shaped guard ring 12', avoiding direct contact and friction between the two during vibration.

[0056] The contact wire dropper clamp 1 uses a 3mm copper alloy plate, which is stamped into a U-shape using a mold. A bolt hole is punched in the center, and the opening is bent inwards at a certain angle. The catenary dropper clamp 15 also uses a 3mm copper alloy plate, which is stamped into a U-shape using a mold. A bolt hole is punched in the center, and a U-shaped threaded clip 18 is installed inside the bolt hole.

[0057] Specifically, in this invention, the material grade of the contact wire suspension wire clamp, the catenary suspension wire clamp, and the upper and lower suspension rings is CuNi2Si, the material grade of the upper and lower heart-shaped retaining rings is 022Cr17Ni12Mo2, and the material grade of the upper and lower crimp terminals is T2.

[0058] In this invention, the clamp body, the lifting eye, the heart-shaped protective ring, and the connecting clamp are all manufactured using a stamping process.

[0059] The installation process of this invention is as follows:

[0060] 1. Installation of contact wire dropper clamp

[0061] According to the design requirements, upper and lower pressure fittings are installed at both ends of the dropper wire. The dropper wire is then wrapped around a heart-shaped retaining ring 360 degrees at both ends before exiting through the upper and lower pressure fittings. The dropper wire is tightened on the crimping platform, ensuring a specified gap between the upper pressure fitting and the upper heart-shaped retaining ring, and between the lower pressure fitting and the lower heart-shaped retaining ring. A mold and specified pressure are then used for crimping. Once the mold closes and the pressure fittings undergo plastic deformation, the pressure is stopped. A dropper wire (referring to a folded dropper wire) with upper and lower heart-shaped retaining rings and short connecting wires at both ends is thus prefabricated. The lower heart-shaped retaining ring of the prefabricated dropper wire is then fitted into the lower dropper of the contact wire dropper wire clamp. In the ring, place the small groove of the contact wire into the clamping plate of the contact wire dropper clamp. Then, put the lower stop washer and the lower crimp terminal together into one end of the hexagonal cap of the fastening bolt. Next, pass the fastening bolt through the screw hole of the U-shaped contact wire dropper clamp. When pulling it out, put another lower stop washer on the other end of the contact wire fastening bolt. After installing the nut, use a wrench to tighten the nut to the specified torque. The contact wire dropper clamp can then clamp the contact wire. Finally, use pliers to turn the six pieces of the lower stop washer so that each piece of the lower stop washer is tightly against the six sides of the hexagonal cap of the fastening bolt and the nut. The installation of the contact wire dropper clamp is now complete.

[0062] 2. Installation of the catenary hanger clamp

[0063] Place the catenary cable into the U-shaped groove of the catenary cable dropper clamp. Place the pre-fabricated upper heart-shaped protective ring of the dropper cable into the U-shaped frame of the catenary cable dropper clamp. Then, insert the upper locking washer and upper crimp terminal into one end of the hexagonal cap of the catenary cable's fastening bolt. Pass the fastening bolt through the threaded hole of the U-shaped catenary cable dropper clamp. When pulling it out, insert another upper locking washer into the other end of the fastening bolt. After installing the nut, insert a U-shaped threaded clip between the catenary cable and the fastening bolt. Tighten the nut to the specified torque using a wrench. The catenary cable dropper clamp will then clamp the catenary cable. Finally, use pliers to manipulate the six segments of the upper locking washer so that each segment is tightly against the hexagonal cap of the fastening bolt and the six sides of the nut. The installation of the catenary cable dropper clamp is now complete.

[0064] The present invention discloses a three-in-one press-fitting method for integral droppers, which simultaneously employs a longitudinal vertical press-fitting method, a transverse elliptical press-fitting method, and a segmented stepped press-fitting method on the upper and lower press-fitting pipes to achieve a "three-in-one" structure. The specific steps include:

[0065] Step 1: Along the vertical center line of the upper pressure tube of the ellipse, use the mold to vertically press the upper pressure tube surface longitudinally, separating the two twisted wires (referring to the two folded suspension wires 11) inside the pressure tube by a small gap to ensure that they do not rub against each other. At the same time, ensure that the generated horizontal pressure is directed radially towards the center of each twisted wire, so that the two twisted wires remain circular after pressing, remain twisted and do not unravel, and do not have uneven wire or strand lengths.

[0066] Step 2: Based on Step 1, use a mold to press the upper pressure tube horizontally in an elliptical shape. The purpose is to increase the frictional resistance between the two strands (referring to the two folded suspension wires) and the upper pressure tube to meet the sliding force requirements of the crimping joint specified by the iron standard.

[0067] Step 3: Divide the crimped tube into three sections. Based on Step 2, use a mold to crimp the upper crimped tube after Step 2 in stages using different crimping forces. The crimping force increases sequentially from the lower end to the upper end of the upper crimped tube in three stages. That is, the pressure of each stage increases sequentially from the outlet of the upper crimped tube. This ensures that the tension of the dropper wire can be transmitted step by step to the entire length of the upper crimped tube. The frictional resistance generated by the entire length of the upper crimped tube is used to balance the tension, rather than just using the frictional resistance generated by the first stage of the crimped tube to balance the tension.

[0068] Step 4: Repeat steps 1 to 3 to complete the crimping of the lower pressure connector; when using different crimping forces to crimp the lower pressure connector in stages, the crimping force should increase in three stages from the top to the bottom of the lower pressure connector, that is, the pressure of each stage should increase in stages from the outlet of the lower pressure connector, so as to ensure that the tension of the dropper wire can be transmitted step by step to the entire length of the lower pressure connector, and the frictional resistance generated by the entire length of the lower pressure connector is used to balance the tension, rather than just using the frictional resistance generated by the first stage of the lower pressure connector to balance the tension.

[0069] The three-in-one press-fitted integral dropper and its press-fitting method proposed in this invention significantly extend the service life of the integral dropper, as demonstrated by the following experiments:

[0070] 1. At the National Railway Product Supervision and Inspection Center, 24 integral droppers assembled using the new pressing method were tested according to the performance specifications for integral droppers at a speed of 400 km / h of China State Railway Group Co., Ltd. (including fatigue testing, where the applied dynamic test force and vibration amplitude were 1.25 times and 1.4 times the standard specifications for a speed of 350 km / h, respectively). All of them passed the test on the first attempt. The test conclusion given by the National Railway Product Supervision and Inspection Center is: the test is qualified.

[0071] 2. The company tested eight integral droppers using the new pressing method with the same testing equipment and according to the above standards, and all passed the tests on the first attempt. The integral droppers could continue to be used even after the fatigue test cycles reached 1.5 times the number specified in the iron standard TB / T2025-2024. The iron standard specifies 2 million fatigue test cycles, while the integral droppers of this invention can reach over 3 million cycles.

[0072] 3. For integral droppers assembled using the traditional pressing method, according to the performance specifications of integral droppers for speeds of 400 km / h issued by China State Railway Group Co., Ltd., it is difficult to meet the stringent requirements for fatigue testing by the number of tests required.

[0073] The adoption of the new "three-in-one" crimping method for droppers and the use of anti-wear droppers are not intended to increase the crimping difficulty, but rather to ensure that the overall service life of droppers is improved, pantograph-catenary failures are reduced, and thus ensure the safety of high-speed train operation under the severe vibration conditions of the high-speed rail catenary.

[0074] To prevent the fastening bolts from loosening during operation, this application installs locking washers and lower locking washers at both ends of the fastening bolts while maintaining the existing machining accuracy of the fastening bolts, effectively preventing the bolts from loosening.

[0075] Because the existing gap between the two vertical sides of the wire-laying groove at the top of the U-shaped lifting ring and the heart-shaped protective ring is too small, the high-speed contact wire will directly contact and generate pressure due to excessive vibration, resulting in dry friction. Now, the two vertical sides of the wire-laying groove at the top of the U-shape of the upper and lower lifting rings are made perpendicular, increasing the gap between them and the upper and lower heart-shaped protective rings, thus avoiding direct contact and friction between the upper lifting ring and the upper heart-shaped protective ring, and between the lower lifting ring and the lower heart-shaped protective ring, during vibration.

[0076] Compared with the prior art, the present invention has the following advantages:

[0077] 1. The three-stage stepped crimping method ensures that the crimping force gradually transitions from the heart-shaped guard ring outlet to the stranded wire outlet, resulting in a uniform transition of crimping force. The transition from tight to loose has a gradual process, ensuring that the stranded wire is gradually stressed. This ensures that the crimped dropper wire can be stressed as a whole, without damaging the original stranded state, preventing the strands from unraveling, and avoiding uneven strand lengths. This achieves the optimal stress state for the flexible dropper wire and prevents breakage.

[0078] 2. Existing lifting rings cannot meet the test conditions of 400 km / h and quickly show wear and cracking. The upper and lower lifting rings of this application are made with the same mold, which can maintain consistency. The flange angle of the upper and lower lifting rings is reasonable, with the flanges forming 90°. At this angle, it is difficult for the edge to come into contact with the arc points on both sides of the inner side of the upper and lower heart-shaped protective rings for wear. The reasonable angle increases the wear area and changes the wear position, which is biased towards the arc of the upper and lower lifting rings. The arc has a thickness of 2 mm and is a surface wear, which greatly improves the wear resistance. Therefore, the upper and lower lifting rings of this application are more wear-resistant and fatigue-resistant than existing lifting rings.

[0079] 3. Installing upper and lower locking washers on both sides of the overall suspension bolt can prevent the bolts from loosening.

[0080] 4. The combined use of the above three points can improve the service life of the stamped integral dropper, reduce pantograph-catenary failures, and ensure the safety of high-speed train operation.

[0081] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A three-in-one press-fit stamped integral dropper, comprising a dropper wire (11), upper and lower heart-shaped retaining rings (12, 12'), upper and lower press-fit connectors (13, 13'), upper and lower U-shaped dropper rings (14, 14'), a catenary dropper wire clamp (15), a contact wire dropper wire clamp (1), and upper and lower press-fit terminals (111, 111'). The upper and lower heart-shaped retaining rings (12, 12') are respectively fitted onto the upper and lower dropper rings (14, 14'). The upper dropper ring (14) is installed on the catenary dropper wire clamp (15), and the lower dropper ring (14') is installed on the contact wire dropper wire clamp (1). 11) One end of the upper heart-shaped retaining ring (12) is wrapped around and connected to the upper crimp terminal (111). The upper crimping tube (13) is close to the end of the upper heart-shaped retaining ring (12) and wrapped and pressed tightly onto the two folded suspension wires (11). The other end of the suspension wire (11) is wrapped around the lower heart-shaped retaining ring (12') and connected to the lower crimp terminal (111'). The lower crimping tube (13') is close to the end of the lower heart-shaped retaining ring (12') and wrapped and pressed tightly onto the two folded suspension wires (11). The upper and lower crimping tubes (13, 13') are provided with three annular pressure grooves (131, 131') spaced apart. The feature is that: The width of the three annular grooves (131) of the upper pressure pipe increases sequentially from the top to the bottom, and the width of the three annular grooves (131') of the lower pressure pipe increases sequentially from the bottom to the top. There is a gap between the two suspension wires in the upper pressure pipe (13) and a gap between the two suspension wires in the lower pressure pipe (13').

2. The three-in-one press-fit stamped integral dropper according to claim 1, characterized in that: The upper ring (14) is installed on the catenary cable hanger clamp (15) by the upper fastening bolt (16). The two ends of the upper fastening bolt (16) are respectively fitted with upper stop washer 1 (17) and upper stop washer 2 (18). The upper stop washer (17) is stamped from a stainless steel plate with a thickness of 1.5mm. The upper stop washer 1 (17) includes an upper collar 1 (171) and four rectangular upper baffles 1 (172) and two L-shaped upper claws 1 (173) that are integrally formed with the upper collar 1 (171) and perpendicular to the plane of the upper collar 1. The four upper rectangular baffles 1 (172) are close to the hexagonal nuts of the upper fastening bolt (16). The two upper claws 1 (173) are located at both ends of the upper collar 1 and are engaged with the catenary cable hanger clamp (1). The upper stop washer 2 (18) includes an upper collar 2 (181) and a rectangular upper baffle 2 (182) that is integrally formed with the upper collar 2 (181) and perpendicular to the plane of the upper collar 2, and two L-shaped upper claws 2 (183). The rectangular upper baffle 2 (182) is in close contact with the nut of the upper fastening bolt (16), and the two upper claws 2 (183) are located at both ends of the upper collar 2 and are engaged with the load-bearing cable hanger clamp (1).

3. The three-in-one press-fit stamped integral dropper according to claim 2, characterized in that: The lower lifting ring (14') is installed on the contact wire dropper clamp (1) by a lower fastening bolt (16'). The two ends of the lower fastening bolt (16') are fitted with a lower stop washer one (17') and a lower stop washer two (18'). Both the lower stop washer one (17') and the lower stop washer two (18') are stamped from stainless steel plates with a thickness of 1.5mm. The lower stop washer (17') includes a lower collar (171') and four rectangular lower baffles (172') and two L-shaped lower claws (173') that are integrally formed with the lower collar (171') and perpendicular to the plane of the lower collar. The four rectangular lower baffles (172') are in close contact with the hexagonal nuts of the lower fastening bolt (16'), and the two lower claws (173') are located at both ends of the lower collar and are engaged with the contact wire dropper clamp (1). The lower stop washer 2 (18') includes a lower collar 2 (181') and a rectangular lower stop 2 (182') that is integrally formed with the lower collar 2 (181') and perpendicular to the plane of the lower collar 2, and two L-shaped lower jaws 2 (183'). The rectangular lower stop 2 (182') is in close contact with the nut of the lower fastening bolt (16'), and the two lower jaws 2 (183') are located at both ends of the lower collar 2 and are engaged with the contact wire dropper clamp (1).

4. The three-in-one press-fit stamped integral dropper according to claim 3, characterized in that: The upper hanging ring (14) has a flange one (141) on its edge, and the angle of the flange one (141) is 90°; the lower hanging ring (14') has two flange two (141') on its edge, and the angle of each flange two (141') is 90°, and the two flange two (141') are flanged to the opposite inner side.

5. The three-in-one press-fit stamped integral dropper according to claim 4, characterized in that: The thickness of the first flange (141) is 2 mm; the thickness of the second flange (141') is 2 mm.

6. The three-in-one press-fit stamped integral dropper according to claim 5, characterized in that: At the top of the U-shape of the upper ring (14), the two flanges (141) are inclined inward at 5 degrees. At the top of the U-shape of the lower ring (14'), the two flanges (141') are inclined inward at 5 degrees.

7. The three-in-one press-fit stamped integral dropper according to claim 6, characterized in that: Both the catenary dropper clamp (15) and the contact wire dropper clamp (1) are made of copper alloy plate with a thickness of 3mm by stamping.

8. A pressing method for a three-in-one press-fit stamped integral dropper as described in any one of claims 1-7, characterized in that: For both the upper and lower press-fit pipes, longitudinal vertical pressing, transverse elliptical pressing, and segmented stepped pressing methods are used simultaneously.

9. The pressing method for the three-in-one press-fit stamped integral dropper according to claim 8, characterized in that: Includes the following steps: Step 1: Press the upper pressure tube vertically along the vertical center line of the upper pressure tube surface of the ellipse, so that the two suspension wire strands inside the upper pressure tube are separated by a small gap, and the two suspension wire strands being pressed together maintain a circular shape. Step 2: Based on Step 1, press the upper pressing pipe after Step 1 into a horizontal elliptical shape; Step 3: Based on Step 2, divide the crimping pipe into three sections and use different crimping forces to crimp the upper crimping pipe after Step 2 in three sections. The crimping force increases sequentially from the lower end to the upper end of the upper crimping pipe in three sections. Step 4: Repeat steps 1 to 3 to complete the crimping of the lower pressure pipe; when using different crimping forces to press the lower pressure pipe in stages, the crimping force increases sequentially in three stages from the upper end to the lower end of the lower pressure pipe.

Images