Final forming machine, method for final forming of thread, and fastening mechanism

Abstract

A final forming machine (1), where the final forming machine (1) is a thread rolling plant, where the final forming machine (1) comprises at least two final forming tools (10, 12) and a sensor device (20), where the sensor device (20) comprises at least one sensor, where the final forming machine (1) is a transverse feed or through feed forming machine, where the sensor device (20) comprises at least one sensor. In particular in the tool conveying direction (L), the final forming tool (10, 12) is designed for final forming of a threaded preform (32) of a blank (40), and the at least one sensor is designed in such a way that the sensor recognizes that the final forming tool (10, 12) detects the threaded preform (32) of the blank (40) in which the final forming tool (10, 12) is inserted into the final forming tool (10, 12), and the final forming tool (10, 12) is inserted into the final forming tool (10, 12). 12) reaches or approaches a thread tail (30) of a thread preform (32) of the blank (40).

Description

Field of the Invention

[0001] The present invention relates to a final profiling machine (Schlussprofiliermaschine), a method for final profiling of a thread, and a fastening mechanism. Background Art

[0002] Threads of bolts, especially high-strength or ultra-high-strength bolts, usually cannot be manufactured by means of a single rolling process because the forces required are usually so high that this may cause or will cause damage or even destruction of the rolling tools. Therefore, the threads of bolts, especially in high-strength or ultra-high-strength bolts, are first pre-rolled or pre-formed, then, if necessary, the threads are quenched and tempered, and then final profiling is carried out in order to thus form the final thread. However, a problem in the final profiling of the thread is that the end region or the thread tail of the thread is not finally profiled. This ultimately results in the thread region having mechanically worse properties and / or being more prone to hydrogen embrittlement compared to the finally profiled region. Summary of the Invention

[0003] Therefore, the object of the present invention is to provide a feasibility for manufacturing or providing a fastening mechanism, especially a bolt, which meets high mechanical requirements within a wide range of the thread and / or has particularly advantageous properties with respect to hydrogen embrittlement in the thread region.

[0004] The object is achieved by means of the final profiling machine according to claim 1, the use of the final profiling tool according to claim 10, the use of the sensor or sensor device according to claim 11, the method for final profiling of a thread according to claim 12, and / or the fastening mechanism according to claim 14. Further advantages, features or embodiments result from the dependent claims, the description and / or the drawings.

[0005] According to the present invention, there is a final forming machine, in particular a thread rolling device. The final forming machine advantageously has at least two, preferably at least three, final forming tools and / or sensor devices. The sensor device includes at least one sensor, where the final forming machine is a transverse feed or through-feed profiling machine (Einlauf-oder Durchlaufprofiliermaschine), in particular a transverse feed or through-feed profiling machine in the tool conveying direction. The final forming tools are advantageously designed to finally form the thread pre-profile of the workpiece blank, and at least one sensor is configured such that the sensor identifies when the final forming tool reaches or approaches the thread end of the thread pre-profile of the workpiece blank. Thus, the final forming machine is in particular a machine for forming a profile by forming, and the final forming machine is advantageously a thread rolling device. In other words, the final forming machine can be used to finally form a thread by forming. The final forming can in particular be understood as the final rolling of a thread. To achieve the final rolling or forming, in particular by rolling a thread, the final forming machine has at least two final forming tools. The final forming tools are here forming tools for forming. In particular, the forming tool or the final forming tool can exactly represent or constitute the profile part of the final forming tool. In other words, the final forming tool is exactly formed by the following components of the final forming tool: the components that engage with the workpiece during the final forming process or during the thread rolling process in order to thus finally form or finally roll the already existing pre-profile of the workpiece blank, in particular the thread pre-profile, by forming. The final forming tools can move relative to each other. This relative movement can here be not only a translational movement but also a rotational movement. Preferably, the rotational relative movement is carried out in the tool conveying direction. Alternatively preferably, the movement of the final forming tools can be not a relative movement but an absolute movement. The translational movement can in particular at least partly also be constituted parallel to the tool conveying direction. The final rolling is advantageously carried out after quenching and tempering, in particular after quenching and tempering of the preformed workpiece blank. Thus, the actual thread manufacturing process is carried out by finally rolling or finally forming the thread. Therefore, the entire thread is manufactured in at least two stages, where the profile depth of the thread pre-profile is less than the profile depth of the standard thread or the final thread. Then, the final forming, which can also be implemented as the final rolling as already described, is carried out such that the depth of the pre-profile thread is increased to the finished thread profile depth. The forming of the thread during the final forming or final rolling is here sufficient to be able to build up intrinsic stress in the thread flanks, thereby producing favorable mechanical properties. In addition, favorable material effects with respect to hydrogen embrittlement can be achieved through this final forming or final rolling of the thread. The final forming tools can here in particular be rolls and / or dies (Walzbacken).The final forming tools of the final forming machine are in particular oriented and / or arranged such that - by the relative movement of the final forming tools with respect to each other - a lateral feed and / or a through-feed of the workpiece or blank to be formed is achieved. In other words, a lateral feed or a through-feed of the blank into or into the gap between the final forming tools can be achieved by the relative movement of the final forming tools with respect to each other. Thus, in other words, the final forming machine can be a laterally feeding or a through-feeding forming machine. The lateral feed direction is in particular the tool feed direction. In accordance with the destination, the tool feed direction is oriented parallel to the longitudinal axis of the blank or workpiece. In the sense of the present invention, a laterally feeding forming machine can alternatively preferably be understood as: by the relative movement of the final forming tools, the workpiece or blank is accelerated or moved in the translational direction. The translational direction is in particular the tool feed direction, and in particular, the workpiece or blank is pulled or moved between the forming tools here. In addition to the final forming tools which are in particular automatically driven, the final forming machine also has a sensor device. The sensor device includes at least one sensor, preferably a plurality of sensors. At least one sensor of the sensors of the sensor device, preferably a plurality of sensors of the sensor device, are configured such that the one or more sensors recognize when the final forming tool reaches the thread end of the thread profile of the blank or when it approaches the thread end. Here, "reaching" should be understood as that all the thread crests or threads of the thread are contacted by the final forming tool or one of the final forming tools not only at one side edge but also at the opposite side edge, and the side edges are in particular thus arranged in the positive tool feed direction and / or the negative tool feed direction with respect to the thread crest or thread. "Approaching" should be understood as the closest contact of one or all of the final forming tools with the blank and / or the minimum distance between the final forming tools from each other, the maximum distance from the thread end being three times the pitch of the thread pre-profile, preferably at most one time the pitch of the thread pre-profile, particularly preferably at most 0.2 times the pitch of the thread pre-profile, very particularly preferably at most 0.1 times the pitch of the thread pre-profile, and most particularly preferably at most 0.05 times the pitch of the thread pre-profile. The thread end is here the end of the thread, where the thread end in particular forms the end of the thread that is not exactly the free end. In other words, for example, in a bolt, the thread end is the end of the thread facing the head. Alternatively or additionally preferably, the thread end can form the transition between the screw and the thread or the end of the thread oriented in that direction away from the thread. Thus, by sensorially detecting whether the final forming tool reaches or approaches the thread end of the thread pre-profile, it can be detected sensorially whether the rolling process must end or should end soon. For this purpose, at least one of the sensors can in particular be a displacement sensor and / or a force sensor.

[0006] Preferably, the final forming tool is a roll, in particular two or three rolls. In other words, the final forming machine can be a two-roll final forming machine or a three-roll final forming machine. With this configuration of the machine, a particularly simple design of the transverse feed or through-feed principle or of a transverse feed or through-feed forming machine can be achieved.

[0007] Alternatively preferably, the final forming tool can be a die, in particular two dies. By configuring the final forming tool as a die, a particularly simple and cost-effective final forming machine can be achieved.

[0008] Advantageously, at least one of the sensors is an optical sensor or a non-contact sensor, and / or at least one of the sensors is a mechanical sensor. The optical sensor can be formed, for example, by a laser or a grating. The advantage of the optical sensor is in particular that a particularly low-wear design can be achieved with the optical sensor. If one of the sensors is to be configured as a mechanical sensor, it is thereby also possible to reliably detect whether the thread end of the thread profile is approached or reached, especially in the case of a high degree of contamination. The mechanical sensor can be, for example, a force gauge. Alternatively or additionally preferably, the sensor can also be a non-contact sensor, in particular a capacitive or inductive sensor. The sensor is also particularly low-wear.

[0009] Advantageously, at least one of the sensors is a displacement measurement sensor. In other words, the sensor can relate, for example, to measuring the position of the blank or workpiece in the tool feed direction. Thus, if a sufficient distance or displacement in the tool feed direction is to be achieved during a transverse feed or through-feed forming method, it is thereby also possible to detect whether the thread end of the thread pre-profile of the blank is approached or reached. Such a displacement measurement sensor can be realized, for example, by a laser, a capacitive and / or an inductive sensor. Alternatively or additionally preferably, the displacement measurement sensor can not only interact with the blank in terms of metrology, but can be arranged such that the displacement measurement sensor detects the movement of one or more final forming tools. In other words, the sensor can indirectly detect, via the tool movement, a conclusion as to whether the final forming tool is approaching or reaching the thread end. However, advantageously, the sensor, in particular the displacement measurement sensor, interacts directly with the blank in terms of metrology. In other words, at least one of the sensors, advantageously the displacement measurement sensor, is arranged such that the sensor can interact with the blank arranged between the final forming tools in terms of metrology.

[0010] Preferably, at least one of the sensors in the sensor is a force sensor, where the force sensor particularly measures the force perpendicular to the tool conveying direction. Such a force sensor can be realized, for example, by a force gauge or by a strain gauge. The principle of the sensor for signalizing the force to detect whether the thread tail of the pre-profile of the blank is reached and / or approached is based on the fact that the thread depth of the thread pre-profile drops strongly in the thread tail, so that the forming force acting on the final forming tool increases strongly. Advantageously, the force sensor measures the force perpendicular to the tool conveying direction here. This is especially a particularly simple and reliable implementation of the force-based detection of whether the thread tail is reached or approached.

[0011] Preferably, the final forming machine has a control unit, where the control unit stops and / or opens and / or separates the final forming tool or one of the final forming tools in the final forming tool according to the sensor signal of at least one sensor of the sensor unit. Here, "stop" should be understood as that the control unit stops the final forming tool in its relative movement with respect to other final forming tools or in its absolute movement. Here, "separate or open" should be understood as that an increased spacing is generated between the final forming tools, so that the final forming tools perform a relative movement with respect to each other or move away, especially a relative movement or move away perpendicular to the tool conveying direction when separated or opened. Here, through the especially away relative movement, especially by using gravity and / or the automatic device of the final forming machine, the blank or workpiece is especially removed from the intermediate space between the final forming tools. In other words, when the final forming tools are opened, the blank or workpiece falls out of the final forming machine. Alternatively, the reverse rotation of the workpiece / blank can also be especially promoted by the final forming tool to remove the workpiece.

[0012] Advantageously, the final forming tool is configured to form a metric thread or other standard threads, especially an imperial thread. In other words, especially a metric thread can be formed or finally rolled or finally formed by means of the final forming machine. Thereby, a particularly wide usability of the final forming machine can be achieved.

[0013] Advantageously, the final forming tool is configured to finally form a thread in a high-strength or ultra-high-strength material. In other words, the final forming tool can be configured such that the final forming tool can also achieve final forming or final rolling in a high-strength or ultra-high-strength material. This can especially be achieved by suitable hardening of the final forming tool. The high-strength material is especially a material: the tensile limit or its tensile strength of the material is at least 800 N / mm 2 , preferably at least 1000 N / mm 2 . On the contrary, the tensile limit or tensile strength of the ultra-high-strength material is at least 1200 N / mm 2 , preferably at least 1400 N / mm2 The feasibility of final forming or final rolling high-strength or ultra-high-strength materials by means of a final forming tool and thus also by means of a final forming machine results in particularly good applicability for bolts of strength classes 8.8, 10.9, 12.9 or even 14.8 or 14.9, 15.8U, 15.9U or higher.

[0014] Another aspect of the present invention may relate to a method for final forming a thread. However, the features disclosed in connection with the method may also be part of a final forming machine, in particular as equipment features. Conversely, however, the equipment features of a final forming machine may also be proposed as method features in a method for final forming a thread. Thus, a method for final forming a thread may in particular be carried out using a final forming machine as described above and below. A method for final forming a thread in particular comprises the following steps:

[0015] - Providing a blank, wherein the blank has a thread pre-profile with a thread tail;

[0016] - Bringing the blank into contact with at least two final forming tools, in particular the final forming tools of a final forming machine, wherein by the movement of at least one final forming tool, the blank is moved or accelerated in the tool feed direction, and wherein by the contact of the blank with the final forming tool, the thread profile is finally formed;

[0017] - Detecting by means of a sensor, in particular a sensor of a sensor device of a final forming machine, whether the final forming tool has reached the thread tail of the thread pre-profile of the blank or is approaching the thread tail of the thread pre-profile of the blank.

[0018] By the movement of at least one final forming tool and bringing the blank into contact with at least two final forming tools, wherein by the movement of at least one final forming tool, the blank is moved or accelerated in the tool feed direction, a lateral feed or through-feed forming is obtained. Here, the advantages described above and below can in particular be achieved by a method for final forming a thread.

[0019] In an advantageous refinement of the method for final forming a thread, the refinement has the following features: the blank consists of or comprises a high-strength or ultra-high-strength material at least in the region of the thread pre-profile. In other words, a final forming machine can thus finally form a thread introduced into a high-strength or ultra-high-strength material. Thereby, particularly good suitability for manufacturing bolts in high-strength or ultra-high-strength form, in particular bolts of strength classes 8.8, 10.9, 12.9, 14.8 or 14.9 or even higher strength classes, in particular 14.9U, can be achieved.

[0020] In particular, the thread pre-profile is tempered before the method for final forming, and pre-forming is carried out before tempering. Thus, in other words, the present invention relates not only to a method for final forming of a thread, but also to a method for manufacturing a fastening mechanism, in particular a bolt.

[0021] Another aspect of the present invention may relate to a fastening mechanism, in particular a bolt. Advantageously, at least a section of, preferably the entire, thread of the fastening mechanism is manufactured and / or finally formed by means of the method described above or below. Alternatively, the bolt can also be manufactured using a final forming machine as described above and / or below. Description of the Drawings

[0022] Other advantages and features of the present invention result from the following description with reference to the drawings. The individual features of the illustrated embodiments can also be used in other embodiments, provided that this is not explicitly excluded.

[0023] The drawings show:

[0024] Figure 1 showing a final forming machine or a part of the final forming machine, where the final forming tool is open; and

[0025] Figure 2 showing the final forming machine, where the final forming tool is in contact with the blank. Detailed Description

[0026] In Figure 1 a final forming machine 1 is shown - at least partially, which final forming machine has two final forming tools 10, 12. The final forming tools 10, 12 can be flat dies or rollers here. The final forming tools 10, 12 are used for final forming or final rolling of the thread pre-profile. By the movement of one of the final forming tools 10, 12, the tool or the blank 40 can be moved in the tool conveying direction L, where the tool conveying direction L extends parallel and / or coaxially to the longitudinal direction of the blank 40, which can also be called the workpiece. In the illustrated case, the final forming tools 10, 12 have reached the thread end 30, such that the control unit (not shown) of the final forming machine 1 has stopped, separated and opened the final forming tools 10, 12. In order to detect whether the final forming tools 10, 12 are approaching or have reached the thread end 30, the final forming machine 1 has a sensor device 20, which in the illustrated example only includes one sensor, which is in turn a force sensor.

[0027] In Figure 2 another design of the final forming machine 1 is shown, where in addition a method step of the method for final forming of a thread is inFigure 2 It is also graphically visible. The blank 40 has a thread pre-profile 32, and the thread pre-profile 32 has a thread tail 30. The blank 40 extends coaxially with the tool feed direction L here, where the tool feed direction L is the direction in which the blank 40 moves due to the movement of one or two final forming tools 10, 12. The final forming machine 1 here has a sensor device 20, which can detect the force perpendicular to the tool feed direction L in the manner of a measuring sensor, and in addition, the final forming machine 1 also has a displacement sensor in its measuring sensor device 20, and the displacement sensor is an optical sensor, especially a laser.

[0028] In Figure 3 it shows the situation where the final forming tools 10, 12 reach or approach the thread tail 30 of the thread pre-profile 32 of the blank 40. Therefore, strictly speaking, in Figure 3 the blank 40 cannot be seen, but the finished part can be seen. Basically, the final forming machine 1 shown in Figure 3 corresponds to or can correspond to the embodiment in another working position in Figure 2 .

[0029] List of reference numerals

[0030] 1 Final forming machine

[0031] 10, 12 Final forming tools

[0032] 20 Sensor device

[0033] 30 Thread tail

[0034] 32 Thread pre-profile

[0035] 40 Blank

[0036] L Tool feed direction

Claims

1. A final forming machine (1), wherein the final forming machine (1) is a thread rolling device, wherein the final forming machine (1) comprises at least two final forming tools (10, 12) and a sensor device (20), wherein the sensor device (20) comprises at least one sensor, wherein the final forming machine (1) is a laterally fed or through-fed forming machine, in particular a laterally fed or through-fed forming machine in the tool feed direction (L), wherein the final forming tools (10, 12) are designed to perform final forming on the thread pre-profile (32) of a workpiece (40), wherein at least one of the sensors is configured such that the sensor identifies when the final forming tools (10, 12) reach the thread end (30) of the thread pre-profile (32) of the workpiece (40) or when approaching the thread end.

2. The final forming machine (1) according to claim 1, wherein the final forming tools (10, 12) are two rolls or three rolls.

3. The final forming machine (1) according to claim 1, wherein the final forming tools (10, 12) are two flat dies.

4. The final forming machine (1) according to any one of the above claims, wherein at least one of the sensors is an optical sensor or a mechanical sensor.

5. The final forming machine (1) according to any one of the above claims, wherein at least one of the sensors is a displacement measuring sensor.

6. The final forming machine (1) according to any one of the above claims, wherein at least one of the sensors is a force sensor, wherein the force sensor particularly measures the force perpendicular to the tool feed direction (L).

7. The final forming machine (1) according to any one of the above claims, wherein the final forming machine (1) has a control unit, wherein the control unit stops and / or separates the final forming tools (10, 12) or one of the final forming tools (10, 12) according to the sensor signals of at least one sensor of the sensor unit.

8. The final forming machine (1) according to any one of the above claims, wherein the final forming tool (10, 12) is configured to form a metric thread.

9. The final forming machine (1) according to any one of the preceding claims, wherein the final forming tool (10, 12) is configured to finally form a thread into a high-strength or ultra-high-strength material.

10. Use of a final forming tool (10, 12) in a final forming machine (1) according to any one of the preceding claims.

11. Use of a sensor or sensor device (20) in a final forming machine (1) according to any one of the preceding claims.

12. A method for finally forming a thread, in particular using a final forming machine (1) according to any one of claims 1 to 9 above, the method comprising the following steps: - providing a blank (40), wherein the blank (40) has a thread pre-profile (32) with a thread tail (30), - bringing the blank (40) into contact with at least two final forming tools (10, 12), wherein by the movement of at least one final forming tool (10, 12), the blank (40) is moved or accelerated in the tool conveying direction (L), wherein by the contact of the blank (40) with the final forming tools (10, 12), the thread pre-profile (32) is finally formed, - detecting by means of a sensor whether the final forming tool (10, 12) has reached the thread tail (30) of the thread pre-profile (32) of the blank (40) or is approaching the thread tail.

13. The method for finally forming a thread according to claim 12, wherein the blank (40) is made of or comprises a high-strength or ultra-high-strength material at least in the region of the thread pre-profile (32).

14. A fastening mechanism, in particular a bolt, wherein at least a section of the thread of the fastening mechanism, preferably completely, is manufactured and / or finally formed by the method according to claim 12 or 13.

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