Hollow rounding of the hottest four Inverted suppo

Four inverted tooth sleeve hollow roll

tooth sleeve is an important stamping part in electrical connectors. After years of production accumulation, two inverted tooth sleeves have formed a relatively mature production process. The forming steps of the two inverted support gear sleeves are: pre bending, seizing, enhancing the core technical competitiveness, inverted support, rounding, and shaping. In order to ensure that the roundness of the inverted support is consistent with the shape of the gear sleeve, the inverted support is arranged after the pre bending step. And the position of the inverted support is at the top or bottom of the arc formed during the pre bending of the gear sleeve, so as to facilitate the circular anastomosis of the convex and concave dies of the inverted support. This kind of gear sleeve hollow rounding process refers to the principle of solid rounding. The pre bending process promotes the plastic deformation of the part towards the circle in the rolling step, so that the part can form a better roundness. The roundness of parts is generally 0.03~0.05, and the seams are parallel

for the four internal inverted support gear sleeve shown in Figure 1, start the test, take 1 standard weight and hang it gently on the upper fixture connecting seat: follow the traditional forming process method of two inverted support gear sleeves, and the steps are: pre bending 1, pre bending 2, rounding and shaping. As shown in Figure 2a, layout:

pre bending and stripping are combined in one process, although one process is reduced. In order to prevent the stamping of parts and ensure the height of reverse support when seizing the reverse support, usually the pre bent parts cannot reliably produce plastic deformation. Although this process solves the problem that the rounding off roundness is consistent with the shape of the gear sleeve, after rounding and shaping, the outer circle of the part becomes a diamond, and the overall roundness reaches 0.2~06. Packaging and process performance experimental instruments (including packaging drop experimental instruments, packaging impact experimental instruments, friction and wear experimental instruments, bending experimental instruments, straightening machines, etc.) 3. Joint dislocation ≥ 0.3. The existence of these process shortcomings directly affects the reliability of electrical connectors

now the forming steps of the four Inverted support gear sleeve are changed to: pre bending, grabbing inverted support, rolling round 1, rolling round 2, shaping. Pre bending and grabbing support are divided into two processes. In the pre bending process, the parts can fully produce plastic deformation. Layout as shown in Figure 2B:

put the punch of pre bending, rounding 1, rounding 2 and shaping process on the unloading plate to avoid the impact of equipment accuracy on the shape of parts, and fix it with a cover plate. The mold design is shown in Figure 3

1 upper die base 2 upper backing plate 3 fixed plate 4 feeding block 5 lower die base 6 large guide post 7 small guide post 8 strip 9 lifting pin 10 side edge 11 window punch 12 punch 13 take down the supporting punch 14 roll round 1 punch 15 roll round 2 punch 16 pre bending punch upper 17 pre bending punch lower 18 take down the supporting concave die 19 roll round 1 concave die 20 roll round 2 concave die 21 integral punch 22 cover plate 23 plastic concave die 24 discharge block 25 concave template 26 lower backing plate

after the mold design is improved, All parts of the part are pre bent, which can fully produce plastic deformation in the direction of the circle. A separate process is used to remove the support, which can not only ensure the height of the support, but also prevent the stamping of parts when removing the support. The edge of the gear sleeve is less prone to plastic deformation than other parts, and it is easy to make the roundness of the seam out of tolerance after rolling. In particular, the edge r of the pre bent punch and die is reduced by about 50%, and the structure is designed as shown in Figure 4A below. The parts are rolled in steps to ensure the roundness of the parts. Adding a stop block to the shaping punch can increase the compressive stress of the shaping steps on the parts, strengthen the plastic deformation of the parts, and prevent the joint dislocation. The structure is shown in Figure 4B:

after production verification, the roundness ≤ 0.08 and joint dislocation ≤ 0.06 after the improvement of the mold design of the large external diameter four Inverted support gear sleeve. Meet the design requirements of gear sleeve

similar process steps can also be taken for the forming of the three inverted support gear sleeve: pre bending, seizing the inverted support, rounding, rounding, shaping. By analogy, we can get five or more inverted teeth nesting. The key points of the process are: when the parts are pre bent, enough plastic deformation will be produced in the direction of the circle, and the roundness of the parts can reach the required roundness, which can also be used as a reference for the hollow roundness of other parts within one year

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