阅读说明：本技术 多级压力机和用于制造成型件的方法 (Multi-stage press and method for producing a molded part ) 是由 J.埃尔哈德 于 2017-12-12 设计创作，主要内容包括：本发明涉及一种用于整体成型金属线区段的多级压力机,包括带有所布置的定尺寸剪切装置的金属线输入机构以及具有夹具的、用于容纳定尺寸剪切的金属线区段并且将所述金属线区段转运到随后的成型级的转运装置,其中,在定尺寸剪切装置(3)的与金属线输入机构(2)面对面的侧面上布置着用于部分加热金属线区段(81)的器件。本发明还涉及用于用这种多级压力机制造成型件的方法。(The invention relates to a multistage press for integrally forming a wire section, comprising a wire feed mechanism with an arranged sizing and cutting device and a transfer device with a gripper for receiving the sizing and cutting wire section and transferring the wire section to a subsequent forming stage, wherein means for partially heating the wire section (81) are arranged on the side of the sizing and cutting device (3) facing the wire feed mechanism (2). The invention also relates to a method for producing shaped parts using such a multistage press.)

1. Multistage press for integrally forming wire sections, comprising a wire infeed mechanism with an arranged sizing shearing device and a transfer device with a gripper for receiving the sizing sheared wire sections and transferring said wire sections to a subsequent forming stage, characterized in that means for partially heating the wire sections (81) are arranged on the side of the sizing shearing device (3) facing the wire infeed mechanism (2), wherein the wire infeed mechanism (2), the forming stage (12) and the sizing shearing device (3) can be actuated independently of one another.

2. Multistage press according to claim 1, characterized in that the means for partially heating the wire section (81) comprise an induction coil (4), wherein the wire feed (2) is provided for temporarily introducing the wire section (81) into the induction coil (4).

3. Multistage press according to claim 2, characterized in that the wire feed (2) comprises a servo drive (21) for defined reciprocating movement of the wire sections.

4. Multistage press according to claim 2 or 3, characterized in that the wire input (2) can be actuated by a control device (6) connected to the wire input, in which a defined dwell time and/or target temperature of the wire section (82) in the induction coil can be stored.

5. Multistage press according to claim 4, characterized in that means for detecting the temperature of the wire sections (82) in the induction coil (4) are arranged, which means are connected to the control device (6), wherein a regulating device is integrated into the control device (6), by means of which the wire feed (2) can be actuated as a function of the temperature of the wire end sections (82).

6. Multistage press according to claim 4 or 5, characterized in that the control device (6) is connected to the sizing and shearing device (3) and is arranged such that after completion of the terminal-side partial heating of the wire section (81), the wire section is sized and sheared with a defined length.

7. Method for producing profiles, in particular screws, using a multistage press, wherein a wire (8) is first heated on the end side, then a wire section (81) is cut to a defined distance from the heated wire end section (82) and the partially heated wire section (81) thus obtained is fed successively to a plurality of forming stages (12) by means of a transfer device (7).

8. Method according to claim 7, characterized in that the wire (8) is fed from a coil to the induction coil (4) via a wire feed (2), where the wire is heated to a defined temperature at a wire end section (82) on the end side.

9. Method according to claim 8, characterized in that the wire (8) is fed to the induction coil (4) via a servo drive (21), wherein the wire (8) is moved into the induction coil (4) according to the desired length of the wire end section (82) to be heated and is moved out of the induction coil (4) again after the desired temperature has been reached or after a dwell duration required therefor, after which the wire section (82) of the desired length is dimensioned to be cut.

10. Method according to claim 9, characterized in that the temperature of the wire end section (82) is accomplished by a contactless temperature sensor, in particular a pyrometer (5).

11. Method according to claim 9, characterized in that the dwell time required in the induction coil (4) to achieve the desired temperature is empirically determined and stored in a control device (6) connected to the servo drive (21).

Technical Field

The invention relates to a multistage press for integrally forming wire sections according to the preamble of claim 1. The invention also relates to a method for producing shaped parts, in particular screws, using a multistage press according to claim 7.

Background

Multi-stage presses for cold forming metal wires are known in various embodiments, for example, from EP 0215338 a 1. Here, the oriented wire is guided from a coil into the machine, where the wire sections defined by the shear are dimensioned. The wire section is fed by the gripper of the transfer device into a first forming stage formed by a die and a punch, where it is positioned in the receptacle of the punch. The wire section is then moved into the die by the die and deformed. After the forming, the formed wire sections are positioned by means of the ejector pins in a further gripper of the transport device and transported by this gripper in each case to the next forming stage. The dies of the forming tools arranged one behind the other are arranged here regularly on a common horizontal cylinder, so that each advance of this cylinder in each of the forming stages completes the deformation of the wire section. The wire sections are shaped to the finished workpiece by successively arranged shaping stages. In the final molding stage, the finished product is ejected. A typical multi-stage press has six forming stages.

The most different cold-formed parts, such as screws or bolts, can be produced with the aid of a multistage press of the type described above. By means of the forming stages arranged one behind the other, high process speeds can be achieved, since six wire sections can be formed at each feed of the cylinder. However, in the case of special materials, such as heat-resistant nickel-based alloys (e.g., NI 53/FE19/CR 19/NB/MO/TI), molding is problematic. In order to produce screws made of this material, the region of the screw head needs to be heated to 1000 ℃ before the screw head is formed. It is to be taken into account here that the screw shaft must be kept cold, since otherwise the quality of the thread to be subsequently introduced into the screw shaft is impaired. In order to produce such special screws, a blank is first produced from the wire section, in which blank the end section is shaped into a screw head under previous heating. These blanks are then fed piece by piece to a multistage press for the manufacture of the desired screws.

A disadvantage of the previously known production method for such special screws is that it is extremely complex. Furthermore, the individual change of the screw length or the screw size is only possible at high expenditure, since for this purpose corresponding blanks have to be produced.

Disclosure of Invention

The invention herein seeks to create a remedy. The object of the invention is to provide a multistage press for integrally forming wire sections, which also makes it possible to produce special screws of the aforementioned type directly from the wire coil. According to the invention, this object is achieved by a multistage press having the features of claim 1.

With the present invention, a multistage press for integrally forming wire sections is provided which also makes it possible to manufacture special screws of the aforementioned type directly from a heat-resistant nickel alloy wire. By arranging means for partially heating the wire section on the side of the sizing and shearing device facing the wire feed, it is possible to heat the defined end-side wire section for the subsequent shaping of the screw head, wherein the wire can be sized and sheared to a desired length after heating the end-side wire section before it is transported by the transfer device to the first deformation stage. By being able to actuate the wire feed mechanism, the forming stage (or the cylinders driving the dies of the forming stage) and the sizing and cutting device independently of one another, it is possible to heat the next end section while simultaneously enabling the wire section that is heated on the end side and subsequently sized and cut to be rapidly formed by all the forming stages.

In an embodiment of the invention, the means for heating the wire section comprise an induction coil, wherein the wire feed mechanism is provided for temporarily introducing the wire section into the induction coil. This enables a defined temperature of the wire section on the end side to be set. The temperature of the wire section is derived from the power output from the induction coil and the dwell time of the wire section within the induction coil.

In one embodiment of the invention, the wire feed mechanism comprises a servo drive for defined reciprocation of the wire section. Thereby, an accurate, on-demand feeding of the wire from the coil is achieved. The possibility of a defined reciprocating movement of the wire makes it possible to introduce the wire end into the induction coil and also to move the wire back subsequently to determine the wire section to be dimensioned for cutting.

In a further embodiment of the invention, the wire feed can be actuated by a control device connected to the wire feed, in which a defined dwell time and/or a target temperature of the wire section in the induction coil can be stored. In this case, a device for detecting the temperature of the wire section located in the induction coil is preferably arranged, said device being connected to a control device, wherein a control device is integrated into the control device, by means of which a wire feed can be actuated as a function of the temperature of the wire section. Alternatively, the dwell time can also be determined empirically to achieve the desired temperature stored in the control device.

In a further embodiment of the invention, the control device is connected to the sizing and shearing device and is configured in such a way that, after the partial heating of the wire section on the end side has been completed, it is sized and sheared to a defined length. This makes it possible to set the length of each screw to be produced individually.

The invention also aims to provide a method for producing special screws of the aforementioned type directly from a coil using a multistage press. According to the invention, this object is achieved by a method having the features of claim 7. By first heating the wire on the end side, subsequently cutting the wire sections in a defined distance from the heated end and subsequently feeding the partially heated wire sections thus obtained to a plurality of forming stages one after the other by means of a transfer device, the length of the screw produced can be set individually. In this case, the wire is preferably fed from a coil via a wire feed to the induction coil, where it is heated to a defined temperature at the end side.

In a further embodiment of the invention, the wire is fed to the induction coil via a servo drive, wherein the wire is moved into the induction coil according to the desired length of the region of the end side to be heated and is moved out of the induction coil again after reaching the desired temperature or after a dwell time required for this purpose, after which the wire section of the desired length is cut to size. Thereby, an accurate process control for manufacturing screws of different lengths from a coil is achieved.

In one embodiment of the invention, the temperature of the region of the end of the wire is measured by a contactless temperature sensor, in particular a pyrometer, or also by an infrared measuring device. Thereby further improving the accuracy of the process control. Alternatively, the dwell time required in the induction coil to achieve the desired temperature can also be determined empirically and stored in a control device connected to the servo drive. In this way, it is also possible to create a database with the dwell time assigned to the respective target temperature in the form of an expert system.

Drawings

Further developments and embodiments of the invention are specified in the remaining dependent claims. One embodiment of the invention is shown in the drawings and described in detail below. In the figure:

fig. 1 is a schematic partial view of a multistage press with induction coils arranged for end side heating of the wire;

fig. 2 schematically shows the arrangement of the wire feed mechanism, the sizing shears and the induction coils for producing the end-side heated wire sections in the multistage press of fig. 1 in the following operating states:

a) the wire is fed from a coil;

b) heating a wire section on the end side in the induction coil;

c) the wire returns with the desired length set; and

d) the cut wire sections are sized in the desired length and received by a transfer device.

Detailed Description

The horizontal multistage press 1 selected as an embodiment is a horizontal multistage press, which is used for manufacturing screws and similar small parts. The construction of such a horizontal multistage press is sufficiently known to the person skilled in the art and is described, for example, in EP 0215338 a 1. The molding tools are arranged side by side here. The transverse transfer device takes the work pieces from one forming stage to another. These presses generally work with a transverse transport slide with a number of transfer grippers corresponding to the number of forming stages, which extend between the die and the matrix of the die. Therefore, a detailed description of such a horizontal multistage press is not given here. The following description focuses on the essential components of the multistage press according to the invention.

Fig. 1 shows a part of a multistage press 1 according to the invention. The female module 11 can be seen with the individual forming stages 12 between which the transfer gripper 71 of the transverse transfer device 7 is arranged. A wire feed mechanism, which is embodied in the exemplary embodiment as a servo drive 2, is arranged upstream of the first molding stage 12. The wire feeding mechanism 2 accommodates a wire 8 unwound from a wire reel, not shown. A separately actuatable wire cutter 3 for size cutting of the wire 8 is arranged upstream of the wire feed mechanism 2. Behind the wire shears 3, viewed from the wire infeed 2, a transfer gripper 71 of the transfer device 7 is positioned, which is provided for receiving a wire section 81 that is cut to size by the wire shears 3. Behind the transfer gripper 71, an induction coil 4 is again arranged, which is positioned in such a way that the wire received by the wire feed mechanism 2 can be moved into the induction coil 4 via the servo drive 21. The wire feed mechanism 2, the wire shears 3 and the induction coil 4 are connected to a control and regulating device 6, which in turn is connected to a pyrometer 5 arranged on the induction coil 4 for measuring the temperature of the wire end section 82 entering the induction coil 4. Furthermore, the control and regulating device 6 is also connected to a transverse transfer device 7 for controlling the transfer gripper 71. The control and regulating device 6 is a component of a not shown overall machine tool control, by means of which the not shown punch modules carrying the individual forming punches are also actuated.

A method for manufacturing a high temperature resistant screw by forming a metal wire from a nickel based alloy is schematically shown in fig. 2. The wire 8 is fed from a coil, not shown, via the wire feed 2 through the wire to the induction coil 4 until a wire end section 82 on the end side of a defined length projects into the induction coil 4. The length to be heated and the desired temperature of the wire end section 82 are stored for this purpose in the control and regulating device 6, which also controls the servo drive 21 of the wire feed 2 (fig. 2 a). Thereafter, the servo driver 21 is stopped, and thus the wire end section 82 temporarily stays in the induction coil 4. The temperature of the wire end section 82 is continuously measured by the pyrometer 5. The measured values are presented to the control and regulating device 6, which compares these measured values with the stored setpoint temperature of the wire end section 82 (fig. 2 b).

After the stored setpoint temperature of the wire end section 82 has been reached, the actuator 21 of the wire feed mechanism 2 is actuated in the opposite direction via the control and regulating device 6, so that the wire 8 is pulled back through the wire feed mechanism 2 until the wire section 71 located behind the wire shear 3 reaches the length stored in the control and regulating device 6 (fig. 2 c). The wire shears 3 are now actuated by the control and regulating device 6, so that the wire section 81 is dimensioned to be sheared in the stored length. The wire section 81 dimensioned in this way is received by the gripper 71 of the transfer device 7 and transferred to the first forming stage 12 of the female module 11 of the multistage press 1. At the same time, the wire 8 is fed back in the direction of the induction coil 4 until the wire end section 82 again projects into the induction coil 4 by the desired length. During the heating of this next wire end section 82, a further forming of the wire section 81 is carried out by a further forming stage 12. The further shaping of the end-side heated wire section 81 inserted into the first shaping stage 12 by the shaping stage 12 of the multistage press is known to the person skilled in the art and is not explained in any further detail here.

It is to be noted here that the drives of the not shown punch blocks which accommodate the individual forming punches are mechanically decoupled from the servo drives of the wire infeed 2 and also from the drives of the transverse transfer device 7. It should also be mentioned that the multistage press according to the invention can be used both for the conventional production of shaped parts by means of continuous cold forming methods. For this purpose, the wire 8 is fed directly, so that a wire section 81 of the desired length is arranged behind the wire shears 3, after which this wire section 81 is dimensioned directly.