Forming machine and method for producing coils

Abstract

The invention relates to a forming machine for producing coils (20, 22) from a strand-shaped material (10), having a material conveyor device (8) which conveys the material along the longitudinal axis (9) and in a feed direction (11), a bending tool (12) which is arranged downstream of the material conveyor device (8) in the feed direction (11) for bending the material (10), and a controller (19) which actuates the material conveyor device (8) and the bending tool (12) in order to produce at least one helical coil (20, 22) by means of a sequence of bending processes. The bending tool (12) is designed to bend material (10) supplied by the material conveyor device (8) at the bending tool front face (36) and material (10) supplied at the bending tool rear face (38) facing away from the material conveyor device (8), and the forming machine (2) additionally has an adjustable tongue (14) for holding a first helical coil (20) which is bent from the material (10) supplied in the feed direction (11), wherein the tongue (14) can be positioned downstream of the bending tool (12) in the feed direction (11), and additionally for clamping the strand-shaped material (10) in an intermediate section (42), which lies between the bending tool (12) and the first coil (20), and for conveying the material (10) clamped in the intermediate section (42) along the longitudinal axis (9) and in an opposite direction (46) which runs opposite the feed direction (11); and an adjustable rear-face guide (16) which can be positioned between the rear face (38) of the bending tool (12) and the tongue (14) and which is designed to guide the material (10) on the rear face of the bending tool (12) when the tongue (14) clamps the material (10) in the intermediate section (42) and supplies same to the bending tool (12) at the rear face (38) thereof in the opposite direction (46) in order to bend the material (10) into a helical second coil (22) by means of the bending tool (12), said second coil lying in front of the first coil (20) when viewed in the feed direction (11) and forming a single-piece double coil (4) together with the first coil.

Description

[0001] Forming machine and method for coil production

[0002] The invention relates to a forming machine for producing coils from strand-shaped material, which has a material conveying device which conveys the material along a longitudinal axis and in a feed direction, a bending tool arranged downstream of the material conveying device in the feed direction for bending the material and a control device which controls the material conveying device and the bending tool in order to produce at least one helical coil by a sequence of bends.

[0003] The invention further relates to a method for producing coils from strand-like material, in which the strand-like material is bent by means of a bending tool into a helical first coil, wherein the material is conveyed in a feed direction.

[0004] There are two basic forming principles for forming strand-like material, for example metal wire material with a round or rectangular cross-section, into helical structures. During winding, the wire material is pushed against a forming element, and this feed causes the stationary forming element to form the wire material into a helical shape, which then usually takes the form of a circular helix. For helical structures that do not rotate in a circle, it is possible to wind the material with a sequence of bends. Winding makes it possible to provide straight sections between individual bends. Such structures are particularly suitable for coils, such as those required for electric motors, for example for so-called disc motors, which are also known as axial flux motors.Here, the basic shape of the individual coils is usually square or trapezoidal, so each turn has two to four essentially straight sections that are connected by bends in such a way that ultimately a helix with the desired basic shape is achieved.

[0005] The forming machines and manufacturing processes mentioned above are established for winding such coils from strand-like material.

[0006] When used in electric motors, individual coils must be electrically connected to one another. Therefore, it is also known to bend the end sections of the coils using appropriate forming devices and place them at suitable locations to simplify the electrical connection of the coils. Nevertheless, the connection technology between the individual coils proves to be comparatively complex.

[0007] The invention is therefore based on the object of developing a forming machine for producing coils from strand-shaped material and a method for producing such coils and also such coils in such a way that the electrical connection of the coils is simplified.

[0008] The invention is characterized in the independent claims. The dependent claims define preferred developments.

[0009] The forming machine for producing coils from stranded material comprises a material conveyor that conveys the material along a longitudinal axis and in a feed direction. The stranded material is typically enamel-insulated wire, but can also be tubing, etc.

[0010] A bending tool designed to bend the material is arranged downstream of the material conveyor in the feed direction. The bending tool is designed such that it can bend material fed in the feed direction by the material conveyor. It is further designed such that it can also bend material fed to it from the opposite rear side, i.e., from the side facing away from the material conveyor. One possible bending tool for this purpose is, for example, a rotary bending tool, as described in detail in EP 2208549 A1, which is incorporated herein in its entirety in this regard.

[0011] The forming machine further comprises a control device that controls the material conveyor and the bending tool. The aim is to produce a helical coil device, designed as a double coil, through a sequence of bends. For this purpose, the forming machine further comprises an adjustable clamp that can hold a helical first coil that was bent when the material was fed to the bending tool from the material conveyor in the feed direction, i.e., from the front of the bending tool. The adjustable clamp can hold the first coil bent in this way. It is arranged downstream of the bending tool in the feed direction, i.e., can be positioned at the rear of the bending tool.Additionally, either the adjustable tongs themselves or a second member functionally associated with the adjustable tongs are configured to clamp the stranded material in an intermediate portion located between the bending tool (more precisely, its rear side) and the first coil. The adjustable tongs thus clamp a portion of the stranded material that lies in front of the first coil in the feed direction and that was delivered by the material conveyor after previously delivered material was bent into the first coil.

[0012] Unlike the prior art, this intermediate section is not severed and provided with bends for easier connection. Instead, the forming machine allows the stranded material to be conveyed further out of the material conveyor without being influenced by the bending tool in the feed direction. The control device controls the material conveyor and the clamp so that the stranded material is conveyed out of the material conveyor over a length determined by the unwound length of a second coil to be produced.

[0013] Since the bending tool is capable of bending material into a coil that is fed to it from its rear side and clamped by the gripper in the intermediate section, it is now possible to retract the material from the rear of the bending tool against the feed direction and bend a second coil using the bending tool. For this purpose, an adjustable rear guide is provided on the forming machine, which can be positioned between the rear of the bending tool and the gripper. This guides the material on the rear of the bending tool when the gripper feeds the material clamped in the intermediate section to the rear of the bending tool against the feed direction.The bending tool bends the material into a helical second coil, which, viewed in the feed direction, is located in front of the first coil and is formed integrally with it, since the first coil and second coil are formed from a continuous part of the strand-like material.

[0014] The manufacturing method, similar to the design of the forming machine, provides that the strand-like material is bent into a helical first coil by means of a bending tool, wherein the material is conveyed in a feed direction. A transition to a helical second coil is then bent. The material is then conveyed a distance in the feed direction without being bent, which distance results from the angled length of the second coil. The material is now clamped in front of the first coil, viewed in the feed direction, and then pushed back against the feed direction. In the process, it is bent into the second coil by means of the bending tool, which then lies in front of the first coil in the feed direction and is formed integrally with it.

[0015] The forming machine and manufacturing process thus make it surprisingly easy to create a double coil consisting of two coil bodies, each identical in its basic geometry, which are manufactured in one piece from a continuous strand of material. The coil bodies represent individual coils and are positioned side by side, so that the coil axes, along which the windings of the coils are stacked, are adjacent. A transition section of the strand of material connects the two coils to form the double coil. These double coils are very advantageous because the connection effort required for installation in an electric motor is halved, since only half the number of coil connections need to be made.

[0016] The counterholder stabilizes the rod-shaped material when it is fed against the feed direction to the bending tool from the back of the tool (the name refers to its position relative to the material conveyor and the conventional use of the bending tool according to the state of the art). The counterholder can only be applied when the strand-shaped material previously fed out of the material conveyor begins to be pushed back. During the production of the first coil, however, it is not in use and must therefore be retracted. This presents the problem of designing the counterholder in such a way that, on the one hand, it can be easily applied to the pulled-out strand-shaped material, but on the other hand, ensures secure guidance, because if the material jumps out of the counterholder, this would produce scrap.It is therefore preferred that the counterholder has a controlled, closable catching device in order to block the strand-like material in the counterholder against movements transverse to the longitudinal axis. This catching device can be designed, for example, as a safety bracket and allows a particularly simple design of the counterholder, which nevertheless ensures that the strand-like material is not lifted out of the counterholder or slips out of it when the second coil is bent (e.g. also not due to the weight of the first coil already formed on the strand-like material and projecting further). A structural design is particularly preferred in which the counterholder has at least one longitudinal groove for receiving the strand-like material. It is inserted into this groove for guidance. When closed, the catching device covers the at least one longitudinal groove so that the strand-like material cannot slip out.Alternatively or additionally, the catching device supplements the cross-section of the longitudinal groove to the strand cross-section of the material, which is thus guided partly by the longitudinal groove and partly by the catching device.

[0017] To provide angled connection terminals on the double coil, it is preferred to provide a tool that can be moved transversely to the coil axis to the longitudinal axis, which tool can be designed, for example, as a pin-mandrel bending tool.

[0018] In order to be able to produce the double coil from the longest possible supply of stranded material, it is preferable to provide a controllable cutting device for severing the material, e.g., a cutting knife, between the material conveying device and the bending tool. The control device activates the cutting device for severing the material after the bending of the first coil is complete and before the bending of the second coil begins. In this way, the stranded material is severed near the material conveying device when the pliers have already gripped the material in the intermediate section, and preferably, the counterholder also guides the stranded material near the rear of the bending device.

[0019] The forming machine has the aforementioned control device, which preferably has a processor and a memory. It controls the material conveying device, the bending tool, the cutting device (if present), and the counterholder. It is designed to control the material conveying device and the bending tool for winding the first coil, with the material being conveyed in the feed direction, i.e., fed to the bending tool from its front side. The bending tool is then controlled to bend a transition section between the first and second coils. This establishes the relative position between the first and second coils according to design specifications for the double coil. The control device then controls the gripper to grip the first coil.The material conveyor is then controlled so that the gripper and material conveyor together convey the material a distance in the feed direction that results from the unwound length of the second coil. The control device now activates the cutting device to cut the material close to the material conveyor. The counterholder is also activated so that it guides the material to the back of the bending tool. The gripper now clamps the material in an intermediate section and pushes it back against the feed direction so that the bending tool, which is also controlled accordingly by the control device, winds the material fed in from its back onto the second coil. This winding process is carried out over the fed-out length so that the two coils, first and second coil, then lie next to each other in the desired geometry, which is predetermined by the transition section.

[0020] The forming machine is thus designed to carry out the method mentioned above by appropriately configuring the control device.

[0021] The aspects described below and above, which were explained in connection with the forming machine, therefore apply equally to the manufacturing process. This also applies vice versa; aspects mentioned for the manufacturing process apply equally to the structural design and operation of the forming machine.

[0022] Reference to the feed direction is understood here in such a way that "in front of" an object in the feed direction refers to a location that would be passed in front of the object in an imaginary movement in the feed direction, i.e., upstream of the object in the feed direction. The term "after" in the feed direction is to be understood inversely.

[0023] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations indicated, but also in other combinations or in isolation, without departing from the scope of the present invention.

[0024] The invention is explained in more detail below using exemplary embodiments with reference to the attached drawings, which also disclose features essential to the invention. These exemplary embodiments are for illustrative purposes only and are not to be interpreted as restrictive. For example, a description of an embodiment with a large number of elements or components should not be interpreted to mean that all of these elements or components are necessary for implementation. Rather, other embodiments may also contain alternative elements and components, fewer elements or components, or additional elements or components. Elements or components of different embodiments may be combined with one another unless otherwise stated. Modifications and variations described for one of the embodiments may also be applicable to other embodiments.To avoid repetition, identical or corresponding elements in different figures are designated by the same reference numerals and are not explained more than once. The figures show:

[0025] Fig. 1 a forming machine for producing double coils,

[0026] Fig. 2 such a double coil,

[0027] Fig. 3 Tools of the forming machine,

[0028] Fig. 4 to 6 the winding of a first coil with the forming machine,

[0029] Fig. 7 shows a preparatory step for winding a second coil formed integrally with the first coil,

[0030] Fig. 8 to 10 the winding of the second coil and the completion of the double coil obtained thereby and Fig. 11 and 12 a counterholder provided in the forming machine which is required for winding the second coil.

[0031] Fig. 1 schematically shows a forming machine 2 for producing double coils 4, which consist of two adjacent coil bodies and are deposited by the forming machine 2 onto a conveyor belt 6. The forming machine 2 has a wire guide 8, which is part of a material conveying device that conveys the strand-like material extending along a longitudinal axis 9 along a feed direction 11 and pushes it out along the wire guide 8. The strand-like material is, for example, a conventional wire 10 with a rectangular cross-section.

[0032] The material conveyor receives the material from a supply. For this purpose, a coil-shaped wire supply and corresponding straightening devices for straightening the drawn wire 10 can be provided in the forming machine 2 or upstream of it. These are not shown in Fig. 1 for simplicity of illustration. The wire 10 is available in a length from which a plurality of double coils 4, in particular at least two or four double coils, are manufactured. This is significantly more advantageous than providing the wire 10 as individual blanks in lengths that correspond exactly to one or two double coils, because the coil geometry and number of windings can then be changed much more easily and less waste is generated.

[0033] The forming machine 2 bends the coils from the wire 10 using a bending tool 12, which in the present example is a rotary draw-bend tool, as described in detail in EP 22085491 A1. Further tools provided in the forming machine 2 include a holding device designed as a pair of pliers 14 for handling the coil bodies. This holding device, as will be explained later, has a dual function, since it also advances the material during winding of a second coil of the double coil 4. Furthermore, a counterholder 16 for producing this second coil and a pin-and-mandrel bending tool 18 are provided, which is used for bends in the connection area of ​​the coil.

[0034] Fig. 2 shows a perspective view of a double coil 4 produced with the forming machine 2. The illustration is mirrored compared to Fig. 1. The double coil 4 consists of two individual coil bodies, namely a first coil 20 and a second coil 22, each formed by a plurality of turns 24 and 25, respectively. The first coil 20 and the second coil 22 are arranged next to one another, i.e., their coil axes, defined by the planes of the turns 24 and 25, run next to one another, usually parallel or at certain angles. The two coils 20, 22 are connected to one another by a transition section 26 and are produced from a single-piece section of the wire 10. The double coil 4 thus has two connection terminals 28, 30, so that only two terminals are available for both coils 20, 22. This simplifies the connection of the two coils 20, 22, since only the double coil 4 needs to be electrically connected. The terminals 28, 30 are provided with bends orBends produced with the pin-mandrel bending tool 18.

[0035] Fig. 3 shows an enlarged view of the tools mentioned for the forming machine 2. Only the cutting knife 17 shown in Fig. 1, which is designed to cut the wire 10 near the wire guide 8, has been omitted for simplicity. As Fig. 3 shows, the individual tools can be positioned by corresponding actuators, and the corresponding degrees of freedom in which the corresponding tool can be adjusted are indicated by double arrows. The tools are controlled by a control device 19 (see Fig. 1) of the forming machine 2.

[0036] The wire guide 8 can retract and extend the wire 10 along its longitudinal axis. The extension occurs in the feed direction 11.

[0037] The pliers 14 have two jaws that can be opened and closed. They are preferably stepped, so that a front area of ​​the pliers can grip a coil 20 or 22, while an inner area of ​​the pliers can clamp wire 10 via a clamping section 15. The significance of this function will be explained below. It will also become clear that holding a coil 20, 22 and clamping the wire 10 are separate functions of the holding device (here, pliers 14), which can therefore optionally also be performed by separate components, e.g., pliers, which then together form the holding device 14.

[0038] The bending tool 12 bends the wire 10 and, for this purpose, has a bending disk 32 and a driver 34. The bending disk 32 is preferably designed as a closable bending die to axially clamp the wire 10. This prevents the wire 10 from thickening when the driver 34 wraps the wire 10 around the bending disk 32.

[0039] The bending tool 12 has a front side 36, which is assigned to the wire guide 8. Opposite it is a rear side 38. The bending tool 12 is designed such that it can bend wire 10 fed along the front side 36 in the feed direction 11, as well as wire 10 fed from the rear side 38 and against the feed direction 11; it is therefore configured for right-left bending. In the illustrated embodiment, this is achieved by the design of a bending tool 12. However, it is equally possible to design the bending tool as a double bending tool with a first and a second bending head, one of which bends wire material fed along the front side 36 and the other bends wire material fed along the rear side 38. The bending heads can then preferably be individually designed for right-hand bending or left-hand bending.

[0040] Fig. 4 shows the bending of the first coil 20 of the double coil 4, wherein the wire 10 is fed in the feed direction from the wire guide 8. After the formation of the first bend, which is shown in Fig. 4, the sequence of turns 24 for the first coil 20 is bent, wherein the wire guide 8 has a corresponding guide head 40 which guides the material 10 fed from the front side 36 during forming (Fig. 5). In the state of Fig. 6, the bending of the first coil 20 is completed and a transition section 26 is formed, wherein the wire 10 continues to exit the wire guide 8 along the feed direction 14.

[0041] Once the first coil 20 has been completed, as can be seen in Fig. 7, the wire 10 is now fed out of the wire guide 8 in the feed direction 11 by a length determined by the unwound length of the second coil 22. This creates an intermediate section 42 that provides the wire path for the second coil 22. During this feeding process, the tongs 14 grip the first coil 20 and guide it in the feed direction 11. The tongs 14 and the wire guide 8 thus cooperate in feeding the wire 10 out over the length of the intermediate section 42.

[0042] Subsequently, as shown in Fig. 8, the pliers 14 place the first coil 20 on a table 44 and clamp the wire 10 in the intermediate section 42. The previously performed severing cut on the wire guide 8 is not shown. It severs the wire 10 after the intermediate section 42 has been fed out. The pliers 14 hold the wire 10 in the intermediate section 42 and feed it in a counter direction 46, which runs opposite to the feed direction 11, so that the bending tool 12 can bend the wire 10, now fed on its rear side 38, to form the second coil. For this purpose, it is necessary to guide the wire 10 on the rear side 38 of the bending tool 12. The counter holder 16, into which the wire 10 has been inserted, serves this purpose. In the exemplary embodiment, the counterholder 16 has an upper guide groove 48 for bending the second terminal 30 and a lower guide groove 50 for bending the individual windings 25 of the second coil 22.

[0043] The dashed representation of the wire 10 and the table 44 illustrates that the intermediate section 42 is actually much longer than shown in Figs. 8 and 9. Its length is determined by the unwound length of the second coil 22 and the connection terminal 30, as can be seen in Fig. 10, in which the intermediate section 42 has meanwhile been wound into the second coil 22. It can also be seen that at a certain point in time, the pliers 14 can no longer clamp the wire 10 in the intermediate section 42, since the wire has already entered the lower guide groove 50 of the counterholder 16. Therefore, at a certain point in time, the pliers 14 no longer grip the wire 10, but rather the coil 20 and push the wire 10 in the opposite direction 46 by a corresponding movement of the coil 20.

[0044] It can also be seen that the lower wire guide 50 is open at the side so that the bending of the second coil 22 can continue until the two coils 20, 22 are directly adjacent to each other. This requires that the transition section 26 can enter the lower guide 50 laterally, transverse to the longitudinal axis 9. Fig. 10 clearly shows this.

[0045] Fig. 11 and 12 show an embodiment of the counterholder 16, which secures the wire 10 in the lower guide 50 as well as in the upper guide 48 during bending. For this purpose, it has a securing bracket 52, which can be lowered onto a lower part of the counterholder 16, in which the guide grooves 48, 50 are formed. This opening and closing of the securing bracket 52 allows additional securing of the wire 10 guided in the corresponding guide groove 48 or 50. The securing bracket 52 is controlled accordingly by the control device 19. The control device 19 is designed such that at least during the formation of the last winding of the second coil 22, the securing bracket 52 is opened so that, as already explained, the transition section 30 can protrude from the laterally open guide groove 50.

[0046] In the variant with a double bending tool, a first bending head is responsible for producing the first coil 20 (Fig. 4-6) and the second bending head is responsible for producing the second coil 22 after cutting (Fig. 8-10).

[0047] The second bending head is then preferably offset from the first bending head—either offset in the feed direction 11, in which case no movement transverse to the feed direction 11 is required with the first coil 20 and the long, straight intermediate section 42, or the second bending head is offset from the first coil transverse to the feed direction 11 (e.g., to the left or right of it). Then, after severing, the first coil 20 and the long, straight intermediate section 42 are moved transversely to the feed direction 11 to the second bending head, in order to subsequently bend the second coil 22.

[0048] It is also possible for the second bending head to be designed to bend in the same direction as the first bending head, but to be turned 180° relative to the first bending head – i.e. to protrude from bottom to top. In this case, the second bending head operates in mirror image, and the first coil 20 is also turned 180° during the transition from Fig. 6 to 7. The counter-guide 16 is coordinated accordingly. Preferably, with this inverted arrangement of the two bending heads, the bending plane of the second bending head is also lower than the bending plane of the first bending head, and the first coil 20 and the intermediate section 42 are lowered accordingly before the intermediate section 42 is fed to the counter-guide 16 and the second bending head. This allows the second bending head to produce the second coil 22 while the first bending head is already bending a first coil 20 of the subsequent double coil 4.

Claims

Patent claims 1. A forming machine for producing coils (20, 22) from strand-shaped, preferably rectangular-cross-sectional, material (10), comprising a material conveyor (8) that conveys the material along a longitudinal axis (9) and in a feed direction (11), a bending tool (12) arranged downstream of the material conveyor (8) in the feed direction (11) for bending the material (10), and a control device (19) that controls the material conveyor (8) and the bending tool (12) in order to produce at least one helical coil (20, 22) through a sequence of bends, characterized in that the bending tool (12) is designed to bend material (10) fed by the material conveyor (8) on its front side (36) as well as to bend material (10) fed on its rear side (38) facing away from the material conveyor (8).and the forming machine (2) further comprises an adjustable holding device (14) for holding a helical first coil (20) bent from the material (10) fed in the feed direction (11), wherein the holding device (14) can be positioned downstream of the bending tool (12) in the feed direction (11) and is additionally designed to clamp the strand-like material (10) in an intermediate section (42) located between the bending tool (12) and the first coil (20), and to convey the material (10) clamped in the intermediate section (42) along the longitudinal axis (9) and in a counter direction (46) running counter to the feed direction (11), and an adjustable rear guide (16) which can be positioned between the rear side (38) of the bending tool (12) and the holding device (14) and which is designed to guide the material (10) on the rear side of the bending tool (12) to lead,when the holding device (14) clamps the material (10) in the intermediate section (42) and feeds it to the bending tool (12) on its rear side (38) in the opposite direction (46) in order to bend the material (10) with the bending tool (12) into a helical second coil (22) which, viewed in the feed direction (11), lies in front of the first coil (20) and forms a one-piece double coil (4) with the latter.

2. Forming machine according to claim 1, characterized in that the rear guide as the counter-holder (16) is equipped with a controlled lockable safety device (52). is formed to block the strand-like material (10) in the counterholder (16) against movements transverse to the longitudinal axis (9).

3. Forming machine according to claim 2, characterized in that the counter-holder (16) has at least one longitudinal groove (48, 50) for receiving the strand-shaped material (10) and the securing device (52) in the closed state covers the longitudinal groove (48, 50) and / or supplements the cross section of the longitudinal groove (48, 50) to the strand cross section of the material (10).

4. Forming machine according to one of the above claims, characterized in that it has a tool (18) which can be moved transversely to the coil axis towards the longitudinal axis for producing bends in the strand-like material (10) which are transverse to the coil axis.

5. Forming machine according to one of the above claims, characterized in that a feed-side end of the material conveying device (8) is designed as a front-side guide (40) which supports the material (10) when it is moved in the feed direction (11) and bent by the bending tool (12) to the first coil (20).

6. Forming machine according to one of the above claims, characterized in that a support table (44) is arranged downstream of the bending tool (12) in the feed direction (11), which supports the first coil (20) while the second coil (22) is bent.

7. Forming machine according to one of the above claims, characterized in that a controllable cutting device (17) for cutting through the material (10) is arranged between the material conveying device (8) and the bending tool (12), and the control device (19) activates the cutting device (17) for cutting through the material (10) after the bending of the first coil (20) is completed and before the bending of the second coil (22) of the double coil (4) begins.

8. Forming machine according to claim 7, characterized in that the control device (19) is designed to: control the material conveying device (8) and the bending tool (12) for winding the first coil (20), wherein the material (10) is conveyed in the feed direction (11), then control the bending tool (12) for bending a transition section to the second coil (22), then control the holding device (14) to grip the first coil (20), and control the material conveying device (8) to convey the material (10) by a distance (42) in the feed direction (11), which distance results from the unwound length of the second coil (22), now to activate the cutting device (17) to cut through the material (10), to control the counter-holder (16) so that it guides the material (10) on the back of the bending tool (12), and then to clamp the material in the intermediate section (42) with the holding device (14) and to push it back against the feed direction (11) and at the same time to control the bending tool (12) to wind the second coil (22).

9. Forming machine according to one of the above claims, characterized in that the bending tool (12) has two bending heads, one of which is designed to bend material (10) fed at the front (36) and the other is designed to bend material (10) fed at the rear (38).

10. A method for producing coils from strand-like material (10), preferably with a rectangular cross-section, in which the strand-like material (10) is bent by means of a bending tool (12) into a helical first coil (20), wherein the material (10) is conveyed in a feed direction (11), characterized in that thereafter a transition (26) to a helical second coil (22) is bent, then the material (10) is conveyed by a distance in the feed direction (11) which results from the unwound length of the second coil (22), and the material (10) is clamped in front of the first coil (20) as seen in the feed direction (11) and then pushed back against the feed direction (11) and is thereby bent by means of the bending tool (12) into the second coil (22) which is integral with the first coil (20) and which is in front of the first coil in the feed direction (11) (20) lies.

11. Method according to claim 10, characterized in that during bending of the second coil (22), the material (10) is guided on the rear side (38) of the bending tool (12) as seen in the feed direction by means of an adjustable rear guide (16).

12. Method according to claim 10 or 11, characterized in that a forming machine (2) according to one of claims 1 to 9 is used.

Images