[0031] Such as Figure 5 , Figure 6 and Figure 7 As shown, the first preferred embodiment of a screw manufacturing device of the present invention includes a machine 3, a first female mold 41, a second female mold 42, and a second female mold 42 that are sequentially installed on the machine 3 A third female mold 43 and a fourth female mold 44, and a first male mold correspondingly located in front of the female molds 41-44 and capable of being driven by a power source to reciprocately press the female molds 41-44 Mold 51, a second male mold 52, a third male mold 53, and a fourth male mold 54. As for the other devices and actions of the screw manufacturing device, they are the same as before, and will not be described again. The male molds 51-54 mentioned above must be matched with the corresponding female molds 41-44 to define the cavity of the predetermined shape in sequence, and the screws of the required shape are formed by forging. Therefore, in the following description, each The female molds and the corresponding male molds are grouped in corresponding order, that is, the relative female molds and male molds are regarded as a group of forging modules. Of course, the female molds and male molds are composed of a plurality of different modules. In this embodiment, only the mold cavity defining the formed blank is described, which means that each female mold has a corresponding male mold. The die opening and each male die have a punch corresponding to the die opening.
[0032] As far as the first forging module is concerned, the first female mold 41 has a first die opening 411 formed on the front end surface, and the first die opening 411 has a long and straight rear circular hole 412 at the rear. And a front opening 413 which is connected to the rear circular hole 412 in the front and is in an expanded shape. The first male mold 51 has a first punch 511 formed on the rear end surface and corresponding to the first die opening 411, and the first punch 511 has a tapered hole formed at the rear end and gradually shrinking forward. 512. A first mold cavity is defined between the opposed first die opening 411 and the first punch 511.
[0033] As far as the second forging module is concerned, the second female mold 42 has a second die opening 421 facing the second male die 52, and the second die opening 421 has a long and straight rear circular hole 422 at the rear. , And a front section opening 423 located at the front and connecting the rear section circular hole 422, the front section opening 423 is expanded into a cone-shaped cylindrical hole. The second male mold 52 has a second punch 521 corresponding to the second die opening 421, and the second punch 521 has a pointed cone 522 protruding from the center of the rear end. A second mold cavity is defined between the second die opening 421 and the second punch 521.
[0034] As far as the third forging module is concerned, the third female mold 43 has a third die opening 431 facing the third male die 53, and the third die opening 431 has a long and straight rear circular hole 432 at the rear. , And a front cylindrical opening 433 located at the front and communicating with the rear circular hole 432. The diameter of the cylindrical opening 433 is larger than the front opening 423 of the second female mold 42. The third male mold 53 has a rear end 531 that is inserted and plugged on the front end of the cylindrical opening 433 of the third mold opening 431, and a corresponding third punch that protrudes into the third mold opening 431 532. The third punch 532 has a hexagonal column section 533 protruding backwards, a tapered neck section 534 formed at the center of the rear end edge of the column section 533 and tapered gradually, and a tapered neck section The end edge of 534 gradually shrinks back into a cone-shaped cone section 535. A third mold cavity is defined between the third die opening 431 and the third punch 532.
[0035] As far as the fourth forging module is concerned, the fourth female mold 44 has a fourth die opening 441 facing the fourth male die 54, and the fourth die opening 441 has a long and straight rear circular hole 442 at the rear. , And a front cylindrical opening 443 located at the front and communicating with the rear circular hole 442. The diameter of the cylindrical opening 443 is slightly larger than that of the cylindrical opening 433 of the third die opening 431. The fourth male mold 54 has a corresponding fourth punch 541 protruding toward the fourth die opening 441, and the fourth punch 541 has a longitudinally protruding rearward extension along a central axis from front to back. Section 542, a neck extension section 543 extending from the rear end of the extension section 542 and gradually curved into a necking shape toward the middle part, a cylindrical section 544 connected to the rear end of the neck extension section 543, and a cylindrical section 544 The end edge of the segment 544 is gradually contracted back into a pointed cone segment 545. The cross-sectional diameter of the rear end of the neck extension section 543 and the cylindrical section 544 is smaller than the diameter of the connection between the tapered neck section 534 and the cone head section 535 of the third punch 532, and the cross section of the middle part of the neck extension section 543 The diameter is smaller than the cross-sectional diameter of the cylindrical section 544. A fourth mold cavity is defined between the fourth die opening 441 and the fourth punch 541.
[0036] Such as Figure 5 and Figure 8 As shown, a comparative embodiment of the manufacturing method of the present invention is performed according to the following steps:
[0037] (1) The first forging module punching forging: the straight rod-shaped blank 6 is placed in the first die mouth 411, and is forged by the corresponding punch 511 of the first punch 511, so as to forge the blank 6 in the first die cavity. The first embryo 61 of the spindle-shaped end 611.
[0038] (2) The second forging die set punching forging: the first blank 61 is placed in the second die opening 421 and forged by the corresponding punch of the second punch 521 to forge a cylindrical shape in the second die cavity The second embryo 62 of the end 621, and the end 621 has a tapered hole 622 extending from the end surface along the central axis.
[0039] (3) Punching for the third forging module: the second blank 62 is placed in the third die 431 and forged by the corresponding punch 532 to forge a cylindrical shape in the third die cavity The third blank 63 of the end 631. The end 631 has an opening 632 extending from the end surface along the central axis. The opening 632 has a hexagonal hexagonal cross-section close to the end surface and arranged in sequence along the central axis. The hole section 633, an extending hole section 634 with a circular cross-section and gradually shrinking, and a tapered hole section 635 with a larger taper than the extending hole section 634 and gradually converging.
[0040] (4) Punching forging of the fourth forging module: The third blank 63 is placed in the fourth die 441 and forged by the corresponding punch 541 to forge the fourth die in the fourth die cavity. Embryo 64. The fourth blank 64 has an opening 641 extending from the opening 632 of the third blank 63, and the opening 641 has a hexagonal hole section 633 identical to the hexagonal hole section 633 of the third blank 63 in sequence along the central axis. The hexagonal hole section 642 of the angular hole, a guide hole section 643 connected to the rear end of the hexagonal hole section 642 and a circular cross-section, and a tapered hole section gradually condensing from the rear end of the guide hole section 643 644.
[0041] Such as Figure 6 and Figure 7 As shown, in the aforementioned third forging die forging process, the rear abutting end 531 of the third punch 532 is inserted and plugged on the front end of the third die opening 431 to form the third blank 63 The third mold cavity becomes a closed space, so at the same time of forging, the third blank 63 will be completely filled in the third mold cavity without leaving the third mold cavity, so that the third blank The corner of the end of the 63 at one end facing a shaft 636 can be formed into a flat surface and a vertical angle, which has a full and complete appearance. The extension hole section 634 and the pointed cone hole section 635 of the third blank 63 are used to guide the fourth punch 541 for punching, and the neck extension section 543 of the fourth punch 541 is designed to be necked. A gap is formed between the fourth blank 64 and the fourth blank 64 to reduce the contact area with the fourth blank 64, which facilitates the entry and exit of the fourth punch 541 before and after forging and prolongs the service life of the fourth punch 541. The diameter of the connection between the tapered neck section 534 and the tapered section 535 of the third punch 532 is slightly larger than the cross-sectional diameter of the cylindrical section 544 of the fourth punch 541, so that the diameter of the formed extension hole section 634 is larger than The diameter of the cylindrical section 544 defines a gap that can accommodate the fourth blank 64 to be filled by the blank material when the fourth punch 541 is punched. Therefore, when the fourth punch 541 is punched during punching, Forging and extending into the fourth embryo 64, the part of the fourth embryo 64 located around the cylindrical section 544 and the tapered section 545 of the fourth punch 541 will be relatively squeezed and deformed to abut against the fourth The periphery of the punch 541, but because of the previously reserved clearance tolerance, the fourth punch 541 will not be trapped and squeezed in the fourth embryo 64, but can smoothly exit the fourth embryo 64 without pulling. Fracture situation.
