Thread rolling machine
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- 有限会社三岛商事
- Filing Date
- 2022-07-06
- Publication Date
- 2026-08-05
Smart Images
Figure 0007900818000001 
Figure 0007900818000002 
Figure 0007900818000003
Abstract
Description
Technical Field
[0004] , , , , ,
[0001] The present invention relates to a forging machine using three round dies.
Background Art
[0002] Forging machines for forging screws are roughly classified into flat die forging machines that forge using flat dies and round die forging machines that forge using round dies. The round die forging machine forms screw threads on the outer peripheral surface of a workpiece by sandwiching a rod-shaped workpiece while rotationally driving a rotatably held round die (see Patent Document 1). In a conventional round die forging machine, the round die has a cylindrical shape with a machining blade formed on its outer peripheral surface, and the round die is selectively fitted onto a main shaft provided on the round die forging machine, and the main shaft and the round die are fastened with a key (see Patent Document 2). Further, the round die forging machine has a two-die method of sandwiching a workpiece with two round dies and a three-die method of sandwiching a workpiece with three round dies. The three-die method is suitable for forging screws on thin-walled hollow parts that are easily crushed because the force of pushing the round die into the workpiece can be dispersed in three directions.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Patent Document 2
Summary of the Invention
Problems to be Solved by the Invention
[0004] A thread rolling machine with round dies can roll threads of different outer diameters by appropriately selecting the round dies. However, the 3-die system is structurally unsuitable for rolling small-diameter threads. As shown in Figure 16, in the 3-die system, if the outer diameter of the workpiece W is too small compared to the outer diameter of the round die 100, the round dies 100 will interfere with each other before they can contact the workpiece W, making it impossible to clamp the workpiece W.
[0005] To address this problem, reducing the outer diameter of the existing round die 100 would allow it to clamp small-diameter workpieces W without causing mutual interference between the round dies 100. However, reducing the diameter of the round die 100 makes it difficult to ensure sufficient strength to withstand thread rolling. For this reason, conventional three-die thread rolling machines are not used for rolling small-diameter screws of M6 (nominal diameter 6 mm) or smaller.
[0006] This invention has been made in view of the current situation, and aims to provide a configuration suitable for rolling small-diameter screws in a thread rolling machine using three round dies. [Means for solving the problem]
[0007] The present invention relates to a rolling machine that rolls a workpiece by pressing three round dies onto it from three sides, wherein the round die is integrally molded with a cylindrical die body having a cutting edge formed on its outer circumference and a main spindle extending axially from the center of the die body on both sides, and the rolling machine is characterized by comprising a spindle holding structure capable of rotatably holding the main spindles on both sides of the round die, a die driving mechanism detachably connected to the ends of the round die and rotating the round die, and a die advancement / retraction mechanism that moves the round die toward and away from a workpiece placement section on which the workpiece is placed.
[0008] In this configuration, the round die is made of solid material, and a fastening mechanism between the round die and the spindle is also unnecessary. As a result, the round die has superior load-bearing capacity compared to the conventional configuration in which it is fitted to the spindle and fastened with a key. Thus, the thread rolling machine of the present invention can use a round die with superior strength compared to the conventional configuration, making it suitable for rolling small diameter threads using small diameter round dies without causing mutual interference between the round dies.
[0009] In the present invention, the spindle holding structure is provided with a plurality of types of die holders, each having a different diameter for the spindle it can hold, and is configured to hold the round die in the die holder of the type corresponding to the diameter of the spindle, and the plurality of types of die holders are proposed to be selectively mountable on the die advancement mechanism.
[0010] As shown in Figure 16, conventional thread rolling machines are configured to selectively attach round dies 100 to a spindle 101 installed in the machine. Since the spindle 101 and spindle holding structure 102 are not replaced unless they are worn out, the spindle 101 is formed to a thickness that can withstand the maximum load, and the spindle holding structure 102 is formed to a size that can support the spindle 101. For this reason, in conventional three-die thread rolling machines, even if the outer diameter of the round dies 100 is reduced to avoid mutual interference between the round dies 100, the spindle holding structures 102 may interfere with each other, making it impossible to narrow the spacing of the round dies 100 to a distance that can grip a small-diameter workpiece W. In contrast, with this configuration, the diameter of the spindle can be changed for each round die, and the die holder can also be changed to match the spindle. Therefore, when rolling small diameter threads, the spindle can be made thinner, and the die holder can be shaped to match the thinner spindle, thereby avoiding mutual interference of the spindle holding structure. Generally, the smaller the nominal diameter of the thread being machined, the smaller the load applied to the spindle. Therefore, when rolling small diameter threads, it is possible to make the spindle thinner than when rolling large diameter threads, while still ensuring the required strength of the spindle, without causing any problems. Thus, with this configuration, the spindle holding structure can be designed to be less prone to mutual interference when round dies are placed in close proximity, making it even more suitable for rolling small-diameter screws.
[0011] In the above configuration, a configuration is proposed in which the die holder, while holding the round die, can be attached to and detached from the die advancement mechanism as an integrated unit.
[0012] In the above configuration, when replacing the round die with one of a different diameter, the die holder also needs to be replaced. However, with this configuration, the round die and die holder can be replaced as a single unit at once, thus reducing the time required to replace the round die.
[0013] In the above configuration, when the die holder is attached to the die advancement mechanism, a plurality of types of tilt angle adjustment blocks are provided to be applied to the die holder, and depending on the type of tilt angle adjustment block applied to the die holder, the tilt angle adjustment block is applied to the die advancement mechanism. Axis of a round die The angle Each die holder A configuration that allows for modification is proposed.
[0014] In in-feed rolling, the axes of each die must be held parallel, while in through-feed rolling, the axes of each die must be tilted relative to each other. Conventional rolling machines (see Patent Document 1) are configured to accommodate both methods by using a servo motor and gears to visually adjust the holding angle of the die. In contrast, with this configuration, the holding angle of the die can be easily adjusted to the required angle by using an inclination angle adjustment block attached to the die holder, thus enabling support for both in-feed and through-feed methods with a simple configuration. [Effects of the Invention]
[0015] As described above, according to the present invention, small-diameter threads can be appropriately rolled in a thread rolling machine using three round dies. [Brief explanation of the drawing]
[0016] [Figure 1] This is a perspective view of the thread rolling machine 1 of the embodiment. [Figure 2]This is a front view of the swaging machine 1 of the embodiment. [Figure 3] This is a left side view of the swaging machine 1 of the embodiment. [Figure 4] This is a front view of the swaging device 3 with the interval between the die units 15 widened. [Figure 5] This is a front view of the swaging device 3 with the interval between the die units 15 narrowed. [Figure 6] This is an explanatory view showing the die advancing / retreating mechanism 16. [Figure 7] This is a perspective view of the die unit 15. [Figure 8] This is a longitudinal sectional view of the die unit 15. [Figure 9] This is an exploded perspective view of the die unit 15. [Figure 10] This is a perspective view of the state where the die unit 15 is attached to the tilting block 60. [Figure 11] This is a perspective view showing the separation of the die unit 15 etc. from the tilting block 60. [Figure 12] This is an explanatory view showing the mode of fixing the rotation angle of the die unit 15 by the tilt angle adjustment blocks 47a and 47b. (A) shows the case of holding so that the axis of the round die 20 faces in the front-rear direction, and (B) shows the case of holding so that the axis of the round die 20 is inclined with respect to the front-rear direction. [Figure 13] (A) is a side view of the round die 20a for M6, (B) is a front view thereof, (C) is a side view of the round die 20b for M5, (D) is a front view thereof, (E) is a side view of the round die 20c for M4, (F) is a front view thereof, (G) is a side view of the round die 20d for M3, and (H) is a front view thereof. [Figure 14] (A) is a side view of the die unit 15a for M6, (B) is a side view of the die unit 15b for M5, (C) is a side view of the die unit 15c for M4, and (D) is a side view of the die unit 15d for M3. [Figure 15] (A) is a front view of the die unit 15a for M6, (B) is a front view of the die unit 15b for M5, (C) is a front view of the die unit 15c for M4, and (D) is a front view of the die unit 15d for M3. [Figure 16] This is an explanatory diagram illustrating the problems with conventional three-die thread rolling machines. [Modes for carrying out the invention]
[0017] Embodiments of the present invention will be described according to the following examples. In the following examples, four types of die holders 25 (25a to 25d) correspond to the spindle holding structure according to the present invention. It corresponds to this.
[0018] As shown in Figures 1 to 3, the thread rolling machine 1 of this embodiment comprises an installation section 2 for mounting the equipment, a thread rolling device 3 for rolling workpieces, a cooling and lubrication device 4 for lubricating and cooling the thread rolling device 3, and a control device 5 for controlling the operation of the thread rolling device 3. This thread rolling machine 1 is a three-die type thread rolling machine, and is used to form screw threads on the outer surface of cylindrical or cylindrical workpieces using three round dies. As will be described later, the thread rolling machine 1 of this embodiment is capable of rolling M3 to M6 (nominal diameter 3 mm to 6 mm) screws, which are difficult to roll with conventional three-die type thread rolling machines.
[0019] The mounting section 2 comprises a table-shaped base 8 and a pair of front and rear mounting plates 9, 9 erected on the base 8. The rolling machine 3 is attached to the mounting plates 9, and the control device 5 is fixed to the upper ends of the mounting plates 9, 9.
[0020] The cooling and lubrication system 4 includes a coolant tank 11 for storing processing oil for both cooling and lubrication, a coolant pump 12 for pumping the processing oil and supplying it to the rolling machine 3, and a coolant recovery tray 13 for recovering the processing oil flowing down from the rolling machine 3.
[0021] As shown in Figures 4 and 5, the thread rolling apparatus 3 is equipped with three sets of die units 15. Each die unit 15 is a unit formed by rotatably holding a round die 20 in a die holder 25. The three sets of die units 15 have substantially the same configuration. The thread rolling apparatus 3 is configured to arrange the workpieces W along the front-to-back direction in the central workpiece placement section 22, and the three sets of die units 15 are arranged around the workpiece placement section 22.
[0022] Each die unit 15 is held by a die advance / retraction mechanism 16 so as to be able to move toward and away from the workpiece placement section 22. Specifically, the die advance / retraction mechanism 16 includes three sets of tilting blocks 60 whose tilting angle is changed by the operation of a linear actuator 61 (see Figures 1-3). The three sets of tilting blocks 60 are arranged in positions that are 120° rotationally symmetrical with respect to the workpiece placement section 22, surrounding the workpiece placement section 22 from three sides. One die unit 15 is attached to each of the tilting blocks 60, and is configured to move toward and away from the workpiece placement section 22 as the tilting of the tilting blocks 60 occurs.
[0023] More specifically, as shown in Figure 6, the die advancement mechanism 16 comprises a movable ring 62 rotatably held on the front side of the mounting plate 9 and a fixed ring 63 fixed non-rotatably inside the movable ring 62. Each tilting block 60 is rotatably pivoted on the front side of the fixed ring 63 and connected to the movable ring 62 via an arm 64. When the movable ring 62 is rotated by the linear actuator 61, the three sets of tilting blocks 60 tilt in sync, causing the three sets of die units 15 to move synchronously toward and away from the workpiece placement section 22. Note that this die advancement mechanism 16 is merely an example, and any die advancement mechanism according to the present invention that moves the die units 15 toward and away from the workpiece placement section 22 is acceptable.
[0024] Each round die 20 held in each die unit 15 is rotationally driven by a die drive mechanism 17. As shown in Figure 3, the die drive mechanism 17 includes a servo motor 50 and a transmission shaft 51. The servo motor 50 is fixed to a mounting plate 9 on the rear side. The transmission shaft 51 transmits the driving force of the servo motor 50 to the round die 20 by connecting its base end to the drive shaft (not shown) of the servo motor 50 and, as shown in Figures 7 and 8, connecting its tip to the rear end of the round die 20. A set of servo motors 50 and transmission shafts 51 is provided for each round die 20, and the rotation angle and rotation speed of the round die 20 can be individually controlled by the operation of each servo motor 50. The transmission shaft 51 is connected to the servo motor 50 and the round die 20 via a universal joint 52 so that it can follow the movement of the round die 20 toward and away from the workpiece placement section 22. Furthermore, as will be described later, since the die unit 15 can be replaced according to the round die 20, the transmission shaft 51 is detachably connected to the round die 20.
[0025] The thread rolling machine 1 of this embodiment uses a round die 20 with an integrally molded spindle 31. Specifically, as shown in Figures 7 to 9, the round die 20 comprises a cylindrical die body 30 with cutting edges 38 formed on its outer circumference, and a spindle 31 extending axially from the center of the die body 30 on both sides. The round die 20 is made by cutting metal, and the die body 30 and the spindle 31 are integrally molded. The cutting edges 38 form a mountain shape that is transferred to the outer circumference of the workpiece W, and are formed in a shape corresponding to the threads of the screw to be machined. A D-cut connecting portion 35 is formed at the rear end of the spindle 31, and the transmission shaft 51 of the die drive mechanism 17 is detachably connected to this connecting portion 35 via a universal joint 52.
[0026] Thus, since the round die 20 is made of a solid material and there is no fastening mechanism between the die body 30 and the spindle 31, it has superior strength compared to a cylindrical round die that fastens to the spindle via a key, even with the same outer diameter. For this reason, the thread rolling machine 1 of this embodiment can easily reduce the outer diameter of the round die 20 (die body 30) that rolls M3 to M6 threads to a size where the round dies 20 do not interfere with each other, while ensuring the strength necessary for thread rolling.
[0027] In this embodiment, the thread rolling machine 1, as shown in Figures 7-9, is unitized as a die unit 15 by rotatably holding the main spindles 31 on both sides of the round die 20 in a die holder 25. The die holder 25 consists of a holder block 26 that is U-shaped in side view, a plurality of bearings 32, 33, and a disc spring 34. The holder block 26 is assembled in a U-shape in side view by positioning pins 41 and bolts 42 to a rectangular plate-shaped base plate 36 and a pair of front and rear side plates 37, 37. The side plates 37, 37 have shaft holding holes 39 through which the main spindles 31 are inserted, and radial bearings 32, 32 are held in each shaft holding hole 39. In addition, a thrust bearing 33 and a disc spring 34 are interposed between the side plate 37 and the die body 30.
[0028] As shown in Figure 9, the die unit 15 is assembled by separating the side plates 37 from the base plate 36, assembling the round die 20, bearings 32, 33, and disc spring 34 between the side plates 37, 37, and then clamping the side plates 37, 37 from both sides and assembling them to the base plate 36.
[0029] The die unit 15 is detachable from the tilting block 60 in unit units. Specifically, as shown in Figures 10 and 11, the die unit 15 is fitted onto a support shaft 48 attached to the tilting block 60, and in this state, the base plate 36 is sandwiched between the retaining plate 46 and the tilting block 60, thereby fixing it to the tilting block 60. An inclination angle adjustment block 47 is interposed between the retaining plate 46 and the base plate 36. The die unit 15 itself is rotatably held on the support shaft 48 of the tilting block 60, but when the die unit 15 is installed, the rotation angle of the die unit 15 relative to the tilting block 60 is fixed by placing the inclination angle adjustment block 47 against the side plate 37. The retaining plate 46 is fastened to the tilting block 60 with bolts 45. By tightening the bolts 45, the die unit 15 is fixed to the tilting block 60. By loosening the bolts 45, the tilt angle adjustment block 47 and the die unit 15 can be attached to and detached from the tilting block 60.
[0030] The thread rolling machine 1 of this embodiment is compatible with both an infeed method, in which the workpiece W is rolled without being moved in the axial direction, and a through-feed method, in which the workpiece W is rolled while being moved in the axial direction. In the infeed method, the axes of each round die 20 are held parallel, while in the through-feed method, the axes of each round die 20 are held at an angle relative to each other. For this reason, the thread rolling machine 1 can fix the die unit 15 with respect to the tilting block 60 at two different rotation angles. Specifically, as shown in Figure 12, the thread rolling machine 1 is equipped with two types of tilt angle adjustment blocks 47 with different shapes, and the die unit 15 can be fixed at two different rotation angles depending on the type of tilt angle adjustment block 47 applied to the die unit 15. More specifically, when rolling in the infeed method, a rectangular parallelepiped-shaped tilt angle adjustment block 47a is applied to each die unit 15, as shown in Figure 12(A). This fixes each die unit 15 so that the axis direction of each round die 20 faces the front-to-back direction, and the axes of each round die 20 are kept parallel. On the other hand, when rolling using a through-feed method, as shown in Figure 12(B), an inclination angle adjustment block 47b with one side inclined is placed on each die unit 15. This fixes each die unit 15 so that the axis of each round die 20 is inclined with respect to the front-to-back direction, and the axes of each round die 20 are kept in an inclined state relative to each other.
[0031] Thus, in this embodiment, the holding angle of the round die 20 can be easily adjusted by selectively applying two types of inclination angle adjustment blocks 47a and 47b to the die unit 15, and with a simple configuration, it can accommodate both infeed and through-feed methods. In this embodiment, the round die 20 can be held at two different angles, but if it is necessary to hold it at three or more angles, an inclination angle adjustment block 47 of a shape corresponding to each holding angle can be added. In the case of a small diameter thread to be processed, as in the thread rolling machine 1 of this embodiment, two types of holding angles for the round die 20 are sufficient: infeed and through-feed.
[0032] The thread rolling machine 1 of this embodiment can roll small-diameter threads that are difficult to roll with conventional three-die thread rolling machines. Specifically, the thread rolling machine 1 of this embodiment is compatible with rolling M3 to M6 threads. In this embodiment, to avoid mutual interference between the round dies 20 when rolling small-diameter threads, a small-diameter round die 20 (die body 30) is used. Furthermore, as described above, in this embodiment, in order to compensate for the lack of strength due to the reduction in diameter of the round die 20, a round die 20 is used in which the die body 30 and the spindle 31 are integrally molded.
[0033] The thread rolling machine 1 of this embodiment selectively uses four different sizes of round dies 20a to 20d depending on the nominal diameter of the screw to be processed. Figure 13 compares the shapes of the round dies 20a to 20d for rolling M3 to M6 screws at the same scale. Although the shape of the cutting edge 38 differs depending on the shape of the screw thread to be processed, basically, when rolling an M6 screw, the M6 round die 20a shown in Figures 13(A) and 13(B) is used. Similarly, when rolling an M5 screw, the M5 round die 20b shown in Figures 13(C) and 13(D) is used, when rolling an M4 screw, the M4 round die 20c shown in Figures 13(E) and 13(F) is used, and when rolling an M3 screw, the M3 round die 20d shown in Figures 13(G) and 13(H) is used.
[0034] As shown in Figure 13, the size of the round dies 20a to 20d used decreases as the nominal diameter of the thread being machined decreases. Specifically, the outer diameter of the die bodies 30a to 30d decreases as the nominal diameter of the thread being machined decreases. This is because, when the nominal diameter of the thread being machined is small, it is necessary to narrow the distance between the die bodies 30a to 30d without causing them to interfere with each other.
[0035] Furthermore, the diameter of the spindles 31a to 31d also decreases as the nominal diameter of the thread being machined decreases. When the nominal diameter of the thread being machined decreases, it is necessary to narrow the distance between the spindles 31a to 31d, but as will be explained later, the thinner the spindles 31a to 31d become, the easier it is to avoid mutual interference of the die holders 25.
[0036] Furthermore, the width (length in the axial direction) of each die body 30a to 30d decreases as the nominal diameter of the thread being processed decreases. This is because making the die bodies 30a to 30d narrower reduces the load applied to the round dies 20a to 20d, making it easier to secure the strength necessary for thread rolling.
[0037] Furthermore, each of the round dies 20a to 20d has the same shape with respect to the connecting portion 35 to which the transmission shaft 51 is connected. This is because all of the round dies 20a to 20d are connected to the transmission shaft 51 via a common universal joint 52.
[0038] The four types of round dies 20a to 20d are each held in different die holders 25a to 25d, thereby forming four types of die units 15a to 15d corresponding to M3 to M6 threads. Specifically, as shown in Figure 14(A), the M6 round die 20a is held in the M6 die holder 25a to form the M6 die unit 15a. Also, as shown in Figure 14(B), the M5 round die 20b is held in the M5 die holder 25b to form the M5 die unit 15b. Also, as shown in Figure 14(C), the M4 round die 20c is held in the M4 die holder 25c to form the M4 die unit 15c. Also, as shown in Figure 14(D), the M3 round die 20d is held in the M3 die holder 25c to form the M3 die unit 15d.
[0039] As shown in Figure 14, each die holder 25a to 25d is shaped to match the size of the round dies 20a to 20d that it holds. Specifically, the shaft holding holes 39 and bearings 32 and 33 of each die holder 25a to 25d are formed to a size corresponding to the diameter of the main shafts 31a to 31d that they hold. In addition, the side plates 37 and 37 of each die holder 25a to 25d are arranged at intervals corresponding to the width of the round dies 20a to 20d that they hold.
[0040] Furthermore, the smaller the nominal diameter of the screw to be machined, the closer the spindles 31a to 31d need to be. Therefore, as shown in Figure 15, for die holders 25a to 25d with smaller nominal diameters of the screws to be machined, the shaft holding holes 39 are formed closer to the ends of the side plates 37 (closer to the workpiece placement area 22) to prevent the side plates 37 from interfering with each other. If the spindles 31a to 31d are large in diameter, the shaft holding holes 39 become larger, making it difficult to form them close to the ends of the side plates 37. Therefore, in this embodiment, the spindles 31a to 31d are made thinner for round dies 20a to 20d with smaller nominal diameters of the screws to be machined, thereby forming the shaft holding holes 39 closer to the ends of the side plates 37.
[0041] On the other hand, each die holder 25a to 25d has the same configuration for mounting to the tilting block 60, such as the thickness of the base plate 36 and the size of the fitting hole 40, and all die units 15a to 15d can be attached to and detached from the tilting block 60 in the same way. Therefore, in this embodiment, depending on the workpiece, four types of die units 15a to 15d can be selectively attached to the tilting block 60 for rolling.
[0042] Specifically, when rolling M6 threads, three sets of M6 die units 15a are attached to the tilting block 60, and as shown in Figure 15(A), three M6 round dies 20a are pressed into the workpiece W from three sides to roll the threads. Similarly, when rolling M5 threads, three sets of M5 die units 15b are attached and rolled, as shown in Figure 15(B). When rolling M4 threads, three sets of M4 die units 15c are attached and rolled, as shown in Figure 15(C). When rolling M3 threads, three sets of M3 die units 15d are attached and rolled, as shown in Figure 15(D).
[0043] As described above, in this embodiment, four different sizes of round dies 20a to 20d are held in four different sizes of die holders 25a to 25d to form die units 15a to 15d. Here, each round die 20a to 20d is made of solid material, and there is no fastening mechanism between the die body 30a to 30d and the spindle 31a to 31d. Therefore, while ensuring the strength necessary for thread rolling, the die body 30a to 30d can be easily reduced to a size that does not interfere with each other when rolling M3 to M6 screws.
[0044] Furthermore, in this embodiment, the spindles 31a to 31d become thinner for round dies 20a to 20d with smaller nominal diameters of the threads to be machined, and the spindle holding holes 39 for holding the spindles 31a to 31d are formed near the ends of the side plates 37. As shown in Figure 15, small diameter threads can be rolled without the die holders 25a to 25d interfering with each other. Note that the smaller the nominal diameter of the threads to be machined, the smaller the load applied to the spindles 31a to 31d, and the lower the required strength of the spindles 31a to 31d. Therefore, even if the spindles 31a to 31d are made thinner to match the nominal diameter of the threads to be machined, the required strength of the spindles 31a to 31d can be ensured. Therefore, the thread rolling machine 1 of this embodiment can roll small-diameter threads without causing mutual interference between the round dies 20a to 20d and the die holders 25a to 25d, while ensuring sufficient strength to withstand thread rolling.
[0045] Furthermore, in this embodiment, the thread rolling machine 1 requires the use of different die holders 25a to 25d depending on the size of the round dies 20a to 20d. However, since the round dies 20a to 20d and the die holders 25a to 25d can be attached to and detached from the tilting block 60 as a single die unit 15a to 15d, there is an advantage in that the round dies 20a to 20d can be replaced in a short amount of time.
[0046] The thread rolling machine 1 in the above embodiment can be used primarily for thread rolling, but it can also be used for other purposes. For example, the thread rolling machine 1 in the above embodiment can also be used for knurling by using a round die 20 with a processing blade 38 of an appropriate shape. Furthermore, the thread rolling machine 1 in the above embodiment can also be used for re-rolling (thread finishing) plated screws.
[0047] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention.
[0048] For example, the thread rolling machine 1 in the above embodiment can roll M3 to M6 threads, but the thread rolling machine of the present invention may be capable of rolling threads smaller than M3, or threads of M7 or larger. Here, when rolling small diameter threads, it is necessary to ensure strength by making the round die 20 from solid material, as in this embodiment, but when rolling large diameter threads, strength can be ensured even if the round die is not made from solid material. Therefore, in the present invention, when both small diameter and large diameter threads can be rolled, the die body and spindle of the round die for large diameter threads may be separate components. [Explanation of Symbols]
[0049] 1. Thread rolling machine 2 Installation section 3. Rolling machine 4 Cooling and lubricating device 5 Control device 8 bases 9 Mounting plate 11 Coolant tank 12 Coolant pump 13 Coolant recovery tray 15, 15a~15d Dice Unit 16. Dice Movement Mechanism 17. Die drive mechanism 20, 20a~20d Round Die 22 Workpiece placement section 25, 25a~25d Die holder (spindle holding structure) 26 Holder Blocks 30, 30a~30d Die body 31,31a~31d Main axis 32 Radial bearings 33 Thrust bearings 34 Disc springs 35 Connecting part 36 Base plate 37 Side panel 39 Shaft holding hole 40 fitting holes 41 Positioning pins 42 volts 45 volts 46 Retaining plate 47, 47a, 47b Inclination angle adjustment block 48 Spindle 50 servo motors 51 Transmission shaft 52 Universal Joint 60 Tilting Blocks 61 Linear Actuator 62 Movable ring 63 Fixed ring 64 Arms 100 round dies 101 Main axis 102 Spindle holding structure
Claims
1. This is a rolling machine that uses three round dies to press into a workpiece from three sides to perform rolling, The aforementioned round die is formed by integrally molding a cylindrical die body with cutting edges formed on its outer surface and a main shaft extending axially from the center of the die body on both sides. A spindle holding structure capable of rotatably holding the spindles on both sides of the round die, A die drive mechanism is detachably connected to the end of the round die and rotates the round die, A die advancement / retraction mechanism moves the round die closer to and further away from the workpiece placement section where the workpiece is placed. Equipped with, The spindle holding structure comprises multiple types of die holders, each capable of holding a spindle of a different diameter. The system is configured to hold one round die in each die holder of a type corresponding to the thickness of the main shaft. A rolling machine characterized in that multiple types of die holders can be individually attached to the die advancement mechanism and can be selectively attached to the die advancement mechanism.
2. The die holder, while holding the round die, is detachable from the die advancement mechanism as an integrated unit. When the die holder is attached to the die advancement mechanism, the die holder is provided with multiple types of tilt angle adjustment blocks that are applied to it. The rolling machine according to claim 1, characterized in that the angle of the axis of the round die with respect to the die advancement mechanism can be changed together with the die holder, depending on the type of tilt angle adjustment block that is applied to the die holder.
3. The die advancement mechanism comprises three tilting blocks arranged to surround the workpiece placement section from three sides and tilting synchronously by the operation of actuators, The die holder is detachably attached to each of the tilting blocks, and is configured to move toward and away from the workpiece placement area in accordance with the tilting of the tilting blocks, as described in claim 1 or 2 of the rolling machine.
4. The die holder comprises a pair of side plates having shaft-holding holes through which the main shaft is inserted, The thread rolling machine according to claim 1 or 2, characterized in that the thinner the die holder that holds the main spindle, the closer the spindle holding hole is formed on the end of the side plate that is closer to the workpiece placement area.