Winding method and machine for winding conducting wire on pole pieces of electric motor rotors

Abstract

A method and automatic winding machine for manufacturing high quality windings on the pole pieces of the rotor of an electric motor using direct in-slot winding technology, thereby overcoming the problems associated with the elasticity of the stack of laminations defining the body of the rotor is described. During winding, the wire is guided by a wire guide cap which can move in the rotor slots, and at the moment, the pole pieces to be wound extend between the rotor slots. The main body of the rotor is pressed tightly by a pressing device inside the wire guide cap. Due to a specific means integrated into the lead guide cap, i.e. By utilizing the volume inside the lead guide cap and providing an axial pressing means therein, an axial pressing of the body for preventing the umbrella effect performed parallel to the rotation axis Z of the rotor is formed.

Description

(19) State Intellectual Property Office (12) Invention Patent Application (10) Application Publication Number (43) Application Publication Date (21) Application Number 202380093636.2 (22) Application Date 2023.12.20 (30) Priority Data 102023000002220 2023.02.09 IT (85) PCT International Application Entering National Phase Date 2025.08.08 (86) PCT International Application Application Data PCT / IB2023 / 063012 2023.12.20 (87) PCT International Application Publication Data WO2024 / 165915 EN 2024.08.15 (71) Applicant: Masli S.A. Address: 14 Via Riparta Alpina, Castelleone, Italy (72) Inventor: Gian Batista Paratti (74) Patent Agency: Shenzhen Mingyue Intellectual Property Agency Co., Ltd. 44304 Patent Attorneys: Sun Weifeng, Wu Cenfei (51) Int.Cl. H02K 15 / 095 (2006.01) H01F 41 / 082 (2006.01) H01F 41 / 088 (2006.01) (54) Invention Title: Winding Method and Machine for Winding Wires on the Pole Plates of a Motor Rotor (57) Abstract: A method and automatic winding machine for manufacturing high-quality windings on the pole plates of a motor rotor using direct in-slot winding technology, thereby overcoming problems related to the elasticity of the laminations that define the body of the rotor. During winding, the wires are guided by wire guide caps that can move in the rotor slots, while the pole plates to be wound extend between the rotor slots. The rotor body is pressed by a pressing device inside the wire guide cap. Due to a specific device integrated into the wire guide cap, namely by utilizing the volume inside the wire guide cap and providing an axial pressing device therein, an axial pressing of the body for preventing the umbrella effect is formed, performed parallel to the rotation axis Z of the rotor. Claims 3 pages Description 12 pages Drawings 12 pages CN 121014158 A 2025.11.25 CN 1 21 01 41 58 A 1. A method for manufacturing a winding (7) of a wire (8) on a pole piece (4) of a rotor (1) of an electric motor by means of an in-slot technique, wherein, during winding, the wire (8) is guided by a wire guide cap (20) movable in the rotor slots (5), the pole piece (4) extending between the rotor slots (5), wherein the body (2) of the rotor (1) is axially pressed by a device (22) inside the wire guide cap (20).2. The method according to claim 1, wherein the body (2) of the rotor (1) is composed of a stacked group of metal laminations (6), and the axial pressing parallel to the rotation axis (Z) of the rotor (1) applied when the wire (8) is wound around the pole piece (4) keeps the height of the group of metal laminations (6) to a minimum by compensating for possible elasticity of the connection between the metal laminations (6). 3. The method according to claim 1 or 2, wherein the pressing is applied throughout the winding process of the wire (8) on the pole piece (4). 4. The method according to any one of the preceding claims, wherein the wire (8) is wound onto the electrode (4) by an automatic winding machine (14) in one of the following ways: - by keeping the body (2) of the rotor (1) stationary and simultaneously moving the wire guide cap (20) alternately in two directions along the proximity axis (Y) in the rotor slot (5), and by winding the wire (8) onto the wire guide cap (20), which in turn provides deposition of the wire onto the electrode (4), or - by moving the wire guide cap (20) alternately in two directions along the proximity axis (Y) in the rotor slot (5), and by rotating the main shaft (15) of the body (2) of the rotor (1) and the wire guide cap (20) together with the pressing device (22) integrated into the wire guide cap (20) simultaneously and integrally on the proximity axis (Y). 5. The method according to claim 4, wherein the rotor (1) has its axis of rotation (Z), and in the automatic winding machine (14), the wire guide cap (20) is readily displaced in a controlled manner in two directions along the approach axis (Y) and radially relative to the axis of rotation (Z) of the rotor (1), and wherein the dimensions of the wire guide cap (20) are designed to substantially surround the pole piece (4) of the rotor (1), and wherein the pressing device (22) is a vise integrated into the wire guide cap (20). 6. The method according to claim 5, wherein: - while winding the wire (8), the vise (22) continuously applies axial pressure to the body (2) of the rotor (1), and the rotor (1), the wire guide cap (20), and the vise (22) rotate integrally, i.e. synchronously, on the proximal axis (Y); - once wound, whenever the rotor (1) remains stationary, the wire guide cap (20) is removed from the pole piece (4), i.e., disengaged from the rotor (1), and the vise (22) opens to disengage from the rotor (1). 7. The method according to any of the preceding claims, wherein the axial pressure is applied at the edge of the pole piece (4) to the body (2) of the rotor (1).8. The method according to any one of the preceding claims, wherein the movement of the wire guide cap (20) depends on the activation or deactivation of the pressing device (22). 9. The method according to any one of the preceding claims, wherein the axial pressure applied by the pressing device (22) to the body (2) of the rotor (1) is adjustable. 10. A slot-type winding machine (14) for forming a winding of a conductor (8) on a pole piece (4) of a rotor (1) of an electric motor, comprising: - a main shaft or support (15) provided with a mounting (19, 21) for supporting a body (2) of the rotor (1); - a tailstock (16) movable relative to the main shaft (15) along a proximity axis (Y) between a proximal position for engaging the body (2) of the rotor (1) supported by the main shaft (15) and a distal position for disengaging from the body (2) of the rotor (1); - a unit (17) for feeding the conductor (8); The tailstock (16) includes a wire guide cap (20) which is movable relative to the main shaft (15) between a position in which the wire guide cap (20) is fully inserted into the rotor groove (5) of the body (2) of the rotor (1) supported by the main shaft (15) and a position in which the wire guide cap (20) is not engaged with the rotor groove (5); and includes a pressing device (22) which is arranged inside the wire guide cap (20) and configured to press the body (2) of the rotor (1) axially. 11. The winding machine (14) according to claim 10, wherein the pressing device (22) is adjustable to apply a calibrated axial pressure parallel to the rotation axis (Z) of the rotor (1) on the body (2) of the rotor (1), particularly a pressure sufficient to counteract the elasticity of the body (2) of the rotor (1) and press the body (2) to a minimum height. 12. The winding machine (14) according to claim 10 or claim 11, wherein the pressing device (22) is operable throughout the winding process.13. The winding machine (14) according to any one of the preceding claims, wherein, in use: - the body (2) of the rotor (1) remains stationary in the spindle or support (15), and the wire guide cap (20) moves alternately in two directions along the approach axis (Y) in the rotor slot (5), and the wire (8) is wound by the feed unit (17) onto the wire guide cap (8), which in turn provides for depositing the wire onto the electrode (4), or - the wire guide cap (20) moves alternately in two directions along the approach axis (Y) in the rotor slot (5), and both the spindle (15) of the body (2) of the rotor (1) and the wire guide cap (20), as well as the pressing device (22) integrated into the wire guide cap (20), rotate simultaneously and integrally on the approach axis (Y). 14. The winding machine (14) according to claim 13, wherein the body (2) of the rotor (1) is supported by the spindle or support (15), wherein the rotation axis (Z) of the rotor (1) is orthogonal to and intersects the approach axis (Y), and wherein the wire guide cap (20) is readily displaced in controlled directions along the approach axis (Y), and wherein the dimensions of the wire guide cap (20) are designed to substantially surround the pole piece (4) of the rotor (1), and wherein the pressing device (22) is a vise integrated into the wire guide cap (20). 15. The winding machine (14) according to claim 14, wherein the spindle (15), together with the body (2) of the rotor (1), the wire guide cap (20), and the vise (22) integrated into the wire guide cap (20), is capable of rotating integrally on the approach axis (Y). 16. The winding machine (14) according to claim 15, wherein the rotation of the wire guide cap (20) and the vise (22) on the approach axis (Y) depends on the activation of the vise (22) on at least one edge of the pole piece (4) of the body (2) of the rotor (1). 17. The winding machine (14) according to any of the preceding claims, wherein the pressing device (22) is a vise comprising two jaws (23, 24) capable of radial movement relative to the approach axis (Y) between a distal position corresponding to the opening of the vise (22) and a proximal position corresponding to the closing of the vise (22).Claims, 2 / 3 pages, CN 121014158 A 18. The winding machine (14) according to claim 17, comprising an actuator for the vise (22), the actuator further comprising a drive shaft (25) extending on the proximity axis (Y), a lever system (27) constrained to the jaws (23, 24), and at least one spring continuously applying a return force to the jaws (23, 24) to bring the jaws to a proximal closed position of the vise (22), wherein the drive shaft (25) slides on the proximity axis (Y) between an engaged position and a disengaged position of the lever system (27), in the engaged position where the lever system (27) counteracts the action of the spring and holds the jaws (23, 24) in the distal open position of the vise (22), and in the disengaged position where the lever system (27) does not counteract the action of the spring and the jaws (23, 24) are in the proximal closed position of the vise (22). 19. The winding machine (14) according to claim 18, wherein the wire guide cap (20) is mounted on a rotating shaft (28) rotatable on the proximity axis (Y), and the drive shaft (25) of the vise (22) is located inside the rotating shaft (28) of the wire guide cap (20) and coaxial with the rotating shaft (28). 20. The winding machine (14) according to any one of the preceding claims, wherein the wire guide cap (20) comprises two halves (20', 20") arranged on opposite sides relative to the pressing device (22) and movable radially away from and toward each other along the approach axis (Y) to change the size of the wire guide cap (20). 21. The winding machine (14) according to any one of the preceding claims, wherein whenever the pressing device (22) engages on the body (2) of the rotor (1), the wire guide cap (20) is movable relative to the pressing device (22) along the approach axis (Y) to insert into the rotor slot (5). Claims 3 / 3 Page 4 CN 121014158 A Winding method and machine for winding wires on pole pieces of a motor rotor Technical Field

[0001] The present invention relates to a method for winding wires on pole pieces of a motor rotor and a corresponding automatic winding machine. Background Art

[0002] As is well known, the main body of an electric motor rotor is formed by stacking (especially overlapping and pressing) multiple metal laminations held together as a single unit. The main body of the rotor defines poles or pole pieces, and wires are wound around the poles or pole pieces to form windings.

[0003] The thickness of each lamination is usually equal to a fraction of a millimeter, e.g., 0.2 - 0.4 mm, and the number of stacked laminations is usually several hundred. For example, the body of a rotor with a height of 150 mm made by stacking laminations with a thickness equal to 0.35 mm has more than 400 laminations.

[0004] Laminations are produced by using metal lamination blanking technology; thus, the thickness of the laminations has a given tolerance. This means that although the thickness variation between laminations is minimal, e.g., a few micrometers, it implies a non-negligible tolerance over the total height of the rotor body. Manufacturers of electric motors that manufacture wire windings on the rotor body must take this tolerance into account.

[0005] A more relevant aspect is that there is also a thickness tolerance between different points on the same lamination. This situation means imperfect overlap of the laminations over their entire surface; a minimum percentile or micrometer-scale gap can be retained between individual laminations, and as a result, the body of the rotor exhibits behavior that can be defined as elastic, with dimensional changes measurable in millimeters. Whenever the body of the rotor is not subjected to an axial compression load (i.e., a compression load parallel to the axis of rotation of the rotor), the height of the body of the rotor is at its maximum, and vice versa. Whenever the body of the rotor is subjected to an axial compression load, the height of the body of the rotor decreases because the gaps between the laminations are eliminated.

[0006] In other words, by applying an axial compression load to the body of the rotor, the laminations are forced to overlap properly, i.e., each lamination rests on the entire surface of the underlying lamination. By removing the load, the body of the lamination undergoes a certain amount of springback and its height increases, so the lamination returns or almost returns to its initial configuration.

[0007] Given the above, it is clear that the height of the rotor body subjected to an axial compression load is less than the height of the same rotor body without an axial load.

[0008] The application of the axial compression load occurs because the wire is wound around the poles of the rotor body. In fact, before being wound around the poles, a winding tension is applied to the wire, i.e., the wire is pre-tensioned in a specific wire tensioning unit that is located upstream of the rotor body with respect to the forward direction of the wire. Thus, as the number of loops effectively wound around the poles of the rotor body increases, the compression load on the rotor body increases correspondingly; for example, assuming a wire with a small diameter is wound with a tension of 1 Kg, and assuming hundreds of winding loops are formed on the poles of the rotor body, the corresponding axial compression load on the rotor body will correspond to hundreds of kilograms. Therefore, the first loop is wound on the body of the rotor with an initial height H, and the last loop is wound on the body of the rotor with a final height h < H. Whenever the winding is completed, the last loop will be properly tensioned, but the first loops will not be tensioned because they will be loose and will thus enjoy a certain degree of freedom of movement, which may cause them to reposition within the winding and relative to the rotor poles, which may degrade the winding layering quality and the mechanical and electrical characteristics of the finished rotor.

[0009] The above-mentioned disadvantages are particularly evident in the case of rotors with wound poles, and even more so compared to rotors with unwound poles, because the essentially cantilevered shape of the poles relative to the central portion of the rotor body (i.e., relative to the axis of rotation) exacerbates the elastic behavior of the body itself, resulting in an effect generally defined as the "umbrella effect." Since the wire windings on the poles provide incremental stacking radially outwards from the rotor, the number of wires in the windings closer to the rotor shaft is less than the number of wires in the windings farther from the shaft. Therefore, the compression applied by the windings is not applied uniformly to the poles, but is greater at the free ends of the poles relative to the base constrained to the rotor shaft; without proper correction, this difference will cause deformation of the lamination assembly, and the rotor body will exhibit an "umbrella-like" shape.

[0010] The following two techniques for winding wires onto the poles of an electric motor rotor and their corresponding winding machines or coil winding machines are also known:

[0011] - Needle winding, generally defined by the English terminology, provides the use of a wire guide needle moving along a desired deposition path in the rotor slots, and a rotor that is stationary or alternately rotating on its own axis of rotation to control the release of wires from the poles, and

[0012] - Direct in-slot winding, generally defined by the English terminology in in-slot technology, provides the use of a metal cap to guide wires into the rotor slots. The wire guide cap is mounted on a tailstock of the winding machine, which is radially movable relative to the rotor to be wound. The wire guide cap moves forward and backward in the rotor slots to guide the deposition of wires on the poles according to a desired layering pattern.

[0013] Typically, whenever needle winding technology is used, a removable vise is used to prevent umbrella effects and ensure proper delamination of the wire. This removable vise is applied to the rotor body to preload the laminations, i.e., to apply the axial compressive load required to minimize the height of the rotor body before winding is performed. The removable vise used to compact the laminations (which define the rotor body) typically has two opposing jaws that can move away from and towards each other, with a spring between the jaws to continuously apply a return force that tends to bring the jaws closer together. The springs with adjustable preload temporarily extend to allow the corresponding vises to be fitted onto the rotor body, and once the vises are installed on the rotor body, they apply a force that tends to tighten the vises, causing the jaws that apply the provided axial load on the laminations to move towards each other. In short, motor manufacturers specify that a sufficient number of vises be installed on the rotor body before winding the wire onto the poles begins. The vises remain on the rotor body throughout the winding operation and are only removed after winding is complete. This solution allows manufacturers to produce windings while maintaining a constant height of the rotor body and a constant tension in the conductors of each ring.The presence of the vise does not interfere with the movement of the wire guide pin: therefore, the vise remains close to the outside of the pole piece, parallel to the rotor axis, i.e., arranged in the axial direction, and the wire guide pin is inserted into the rotor slot along a path around the pole piece and the corresponding vise. As described above, the vise is removed from the pole piece only when winding is complete and the wire guide pin has been removed. The vise is collected from the storage bin, mounted on the rotor pole piece, and automatically retracted after use.

[0014] However, the solution just described cannot be used for direct in-slot winding (in-slot technique) due to the presence of the tailstock of the winding machine, which would occupy exactly the space originally used by the vise. In fact, the tailstock must abut against the pole piece in the radial direction so that the wire guide cap extends within the rotor slot, and this is not possible in the presence of the vise.

[0015] JP 2012135077 describes a winding machine for direct in-slot winding in which the tailstock abuts against the pole piece and applies radial pressure thereon, i.e., pressure in a direction orthogonal to the axis of rotation of the rotor.

[0016] JP ​​H02111245A describes a machine similar to the aforementioned machine. Furthermore, the machine is equipped with an anti-rotation element identified by reference numeral 14 in FIG. 2. The anti-rotation element is dovetail-shaped to engage the pole pieces via a shaped connection used to prevent relative rotation between the lamination assembly and the tailstock. The anti-rotation element is not designed to apply pressure to the pole pieces. Summary of the Invention

[0017] The object of the present invention is to provide a method and an automatic winding machine (coil winding machine) that allows the manufacture of high-quality windings on the pole pieces of a motor rotor using the direct slot winding technique described in the specification 2 / 12 pages 6 CN 121014158 A, thereby overcoming problems related to the elasticity of the lamination assembly defining the body of the rotor.

[0018] Therefore, a first aspect of the invention relates to the method according to claim 1.

[0019] During winding, the wire is guided by a wire guide cap that is movable in the rotor slot, which defines the pole piece to be wound at this time.

[0020] Advantageously, the method provides pressing of the rotor body by means of a pressing device inside the wire guide cap. Due to the specific device integrated into the wire guide cap, pressing of the body in the axial direction (i.e., parallel to the rotor's axis of rotation Z) is achieved to prevent the umbrella effect.

[0021] The aforementioned technical problem is solved by utilizing the volume within the wire guide cap and arranging the pressing device therein, thereby enabling axial pressing of the wound rotor body by compensating for the elasticity of the lamination assembly.

[0022] The axial pressing, parallel to the axis of rotation of the finished rotor, applied when the wire is wound onto the pole pieces, keeps the height of the metal lamination assembly constituting the rotor body minimal; thus, the elasticity of the connection between the metal laminations is compensated.

[0023] Preferably, axial pressing is applied throughout the winding of the wire on the pole piece, and thus begins immediately before winding begins and ends immediately after the winding has been wound.

[0024] The wire is wound onto the pole piece using an automatic winding machine. For example, the following methods (flywheel, rotating spindle) are possible:

[0025] - Keeping the rotor body stationary and simultaneously moving the wire guide cap in the rotor slot alternately in two directions along the approach axis Y radially relative to the rotor's axis of rotation Z, and winding the wire onto the wire guide cap, which in turn provides a solution for depositing the wire onto the pole piece according to what can be defined as in-slot flywheel winding, or

[0026] - Moving the wire guide cap alternately in two directions along the approach axis Y in the rotor slot, and simultaneously causing the spindle to rotate integrally with the rotor body and the wire guide cap, as well as the pressing device integrated into the wire guide cap, on the approach axis Y and maintaining constraint (pressing device to rotor body and rotor body to spindle), which can be defined as a solution for rotating spindle in slot winding.

[0027] In other words, the winding machine can be configured such that the wire is wound around the wire guide cap, which provides proper positioning of the wire on the pole pieces (flywheel winding). Furthermore, the rotor and cap rotate together, thereby pulling the wire on the wire guide cap and thus the wire on the pole pieces (rotary spindle winding).

[0028] Preferably, in an automatic winding machine, the wire guide cap is readily displaced radially in both directions along the approximate axis Y and relative to the rotation axis Z of the rotor supported by the spindle. The wire guide cap is sized to substantially surround the pole pieces of the rotor, and the pressing device is a vise integrated into the wire guide cap. Corresponding to the instantaneous position of the wire guide cap in the rotor slot, the method also provides for modifying the size of the wire guide cap to fit the pole pieces of the rotor.

[0029] Preferably, during wire winding, the pressing device constantly applies axial pressure, i.e., pressure parallel to the rotation axis Z of the rotor, and the rotor, wire guide cap, and pressing device rotate integrally (i.e. synchronously) about the approximate axis. Once wound, whenever the rotor remains stationary relative to an external reference system, the wire guide cap is removed from the pole, i.e., disengaged from the rotor, and the pressing device is deactivated to disengage the rotor.

[0030] Preferably, axial pressure is applied to the rotor body by the pressing device at the edge of the pole.

[0031] Preferably, the movement of the wire guide cap depends on the activation or deactivation of the pressing device; this prevents the winding machine from continuing to wind the wire whenever the rotor body is not held at the minimum height, i.e., the minimum axial range (axis Z).

[0032] This method can be achieved by providing adjustable pressure applied axially to the rotor body by the pressing device; this allows the winding machine to be adapted to rotors of different sizes, i.e., bodies with different numbers of metal laminations.

[0033] A second aspect of the invention relates to an automatic machine according to claim 10, for forming a winding of a conductor on the pole pieces of an electric motor rotor.

[0034] The machine comprises:

[0035] - a main shaft or support provided with means for supporting a body of a rotor; - a tailstock movable relative to the main shaft along a proximal axis Y between a proximal position for engaging the body of the rotor supported by the main shaft and a distal position for disengaging from the body of the rotor;

[0036] - a unit for feeding the conductor.

[0037] The tailstock includes a conductor guide cap movable relative to the main shaft between a position in which the conductor guide cap is maximally inserted into a rotor slot (particularly a slot in which the pole pieces extend) of the body of the rotor supported by the main shaft and a position in which the conductor guide cap is minimally inserted or disengaged, in which position the conductor guide cap does not engage the rotor slot and therefore does not engage the pole pieces.

[0038] Advantageously, the winding machine includes an axial pressing device arranged inside the wire guide cap and configured to press the rotor body in a direction parallel to the rotation axis Z of the finished rotor (i.e., the axis Z on which the rotor is intended to rotate on the stator when assembled with the corresponding stator); thus, axial pressing parallel to the height of the pole pieces occurs.

[0039] Utilizing the internal volume of the wire guide cap to accommodate the pressing device allows the rotor body to be compacted, thereby preventing the umbrella effect without hindering the wire winding operation. Therefore, the proposed solution allows for the formation of windings of improved quality without increasing machine cycles (i.e., in the same time as a solution without pressing).

[0040] Preferably, the pressing device is adjustable to apply a calibrated axial pressure to the rotor body, particularly sufficient to counteract the elasticity of the body due to the constraints between the correspondingly stacked metal laminations and press it to a minimum height. Adjustment of the axial pressure allows the winding machine to be configured with rotors of different sizes, thus making the machine versatile.

[0041] In a preferred embodiment, the pressing device can be operated throughout the winding process. This ensures that whenever a pre-tensioned conductor is provided, the tension of each loop of the winding is equal to the tension of the other loops in the same winding. Alternatively, it is also possible to deactivate the pressing device before winding is complete, provided that a sufficient number of loops have been wound on the pole pieces and the rotor body is no longer subject to the springback of the metal laminations.

[0042] In a first embodiment, whenever the winding machine is in use, the rotor body remains stationary in the spindle or support (relative to an external reference system, such as the environment in which the machine is located), and the conductor guide cap moves alternately in two directions along the near axis Y in the rotor slots. The conductor provided by the feed unit is wound onto the conductor guide cap, which in turn provides the means to deposit the conductor onto the pole pieces.In practice, the feed unit rotates about the proximity axis Y to bring the wire onto the wire guide cap, while the wire guide cap moves in the rotor slot to place the wire in the appropriate position.

[0043] In a preferred second embodiment, when the winding machine is operating, the wire guide cap moves alternately in two directions along the proximity axis Y in the rotor slot, and the machine simultaneously provides a mechanism to rotate the spindle together with the rotor body, the wire guide cap, and the pressing device integrated into the wire guide cap on the proximity axis Y. Therefore, in this embodiment, the feed unit for feeding the wire does not move, precisely because the wire guide cap pulls the wire back by rotating on the proximity axis Y.

[0044] Preferably, the rotor body is supported by a spindle or support, wherein the rotor's axis of rotation Z is orthogonal to and intersects the proximity axis Y. The wire guide cap is readily displaced in controlled directions along the proximity axis Y. The wire guide cap is sized to substantially surround the pole piece of the rotor to be wound with the wire. The pressing device is a vise integrated into the wire guide cap, i.e., inside the wire guide cap and working in conjunction with it to apply axial pressure on the lamination assembly, i.e., parallel to the rotor's axis of rotation Z.

[0045] Preferably, the spindle, together with the rotor body supported therein, the wire guide cap, and the vise integrated into the wire guide cap, can rotate integrally on the proximal axis Y, i.e., rotate as a whole. Specification 4 / 12 pages 8 CN 121014158 A

[0046] Preferably, the rotation of the wire guide cap and the vise on the proximal axis depends on the activation of the vise on at least one edge of the pole piece of the rotor body, so that the deposition of the wire ensures that the rotor body is axially compacted and not subjected to umbrella effect.

[0047] In a preferred embodiment, the pressing device is a vise. The vise includes two jaws that are radially movable relative to the proximal axis Y, and thus parallel to the axis of rotation Z of the rotor supported by the spindle. The jaws can move between a distal position corresponding to the vise being open and a proximal position corresponding to the vise being closed. With the vise open, the jaws can disengage from and abut against the rotor body. With the vise closed, the jaws apply pressure to the rotor body to compress it to a minimum axial range (relative to axis Z).

[0048] The vise can be of various types, such as hydraulic, but is preferably mechanical; the vise actuator is mounted on the tailstock. The actuator includes a drive shaft extending near axis Y, a lever system constrained to the jaws, and one or more springs that continuously apply a restoring force to the jaws to bring the jaws to a proximal closed position of the vise. With this configuration, the vise is generally held in the closed position, and the actuator intervenes to temporarily bring it to the open position. The machine can also be configured to have reverse kinematics, i.e., springs that tend to open the vise and actuators that hold the vise closed.The operation of the vise provides displacement of the drive shaft on the proximal axis Y between the following positions:

[0049] - an engaged position of the lever system, where the lever system counteracts the spring action and holds the jaws in the distal open position of the vise, and

[0050] - a disengaged position, where the drive shaft does not exert a thrust on the lever system sufficient to counteract the spring action, and the jaws are in the proximal closed position of the vise. Alternating movement of the vise's drive shaft on the proximal axis Y can be imparted, for example, by an electric linear actuator.

[0051] In an alternative embodiment, the operation of the vise can be achieved by providing an actuator with radial movement relative to the axis of rotation.

[0052] In a preferred embodiment, the wire guide cap is mounted on a rotating shaft rotatable on the proximal axis. The drive shaft of the vise is located inside and coaxial with the rotating shaft of the wire guide cap. As will become clearer in the following description, this configuration allows the drive shaft of the vise and the rotation axis of the wire guide cap to rotate synchronously whenever the wire is wound around the pole piece of the rotor, and whenever the vise must open to disengage from the rotor, this configuration allows the drive shaft of the vise to move relative to the rotation axis of the wire guide cap along the proximity axis Y.

[0053] Thus, due to this configuration of the corresponding actuators sharing the space in the internal volume of the wire guide cap, the integration of the vise into the wire guide cap is achieved. Therefore, the vise does not occupy space outside the wire guide cap.

[0054] The wire guide cap has a variable geometry for adjusting its size to the geometry of the pole piece during winding, and in particular, for engaging the rotor slot during the radial movement of the wire guide cap along the proximity axis Y relative to the rotation axis Z of the rotor between the minimum insertion position and the maximum insertion position. The wire guide cap has a general conical shape, so if the geometry of the wire guide cap were not changeable, it would be impossible for the wire guide cap to be fully inserted into the rotor slot without disturbance.

[0055] Preferably, the wire guide cap is defined by two halves arranged on opposite sides relative to the pressing device (i.e., vise). The two halves of the wire guide cap can be moved radially away from and toward each other relative to the near axis Y to change the size of the wire guide cap and allow it to be inserted into the rotor slot.

[0056] The operation of the winding machine provides that the body of the rotor is positioned on the spindle with the pole facing the tailstock; before starting to rotate the spindle and the body of the rotor, the tailstock is brought against the body of the stationary rotor at the pole where the wire is to be wound, and the pressing device (vise) is operated to press the body of the rotor. The spindle is started to keep the body of the rotor rotating on the near axis Y, and the tailstock rotates together with the spindle and the body of the rotor. The wire slides on the outer surface of the wire guide cap, which positions the wire according to a predetermined winding pattern by moving forward and backward in the rotor slot until winding is complete.Whenever the winding has been wound onto the pole piece, the main shaft and tailstock stop, that is, the rotation on the near axis Y is interrupted, and the pressing device is deactivated to release the rotor body; the tailstock moves away from the main shaft, and the rotor body rotates on its rotation axis Z so that the new pole piece faces the tailstock, ready for a new winding cycle.

[0057] Further features and advantages of the invention will become clearer upon reading the following detailed description of preferred but non-exclusive embodiments thereof, which are illustrated by way of example rather than limitation by means of the accompanying drawings, in which:

[0058] FIG1 is a perspective and front view of a rotor having wound poles manufactured using the method and machine of the invention;

[0059] FIG2 is a front view and axial sectional view of a rotor portion, particularly a front view and axial sectional view of one of its pole pieces, the rotor portion being combined with a vise and pre-arranged for winding a wire according to a known needle winding technique;

[0060] FIG3 is a perspective bottom view of the rotor portion and vise shown in FIG2;

[0061] FIG4 is a bottom view of the rotor portion and vise shown in FIG2;

[0062] FIG5 is a perspective and front view of a needle winding machine (coil winding machine) according to the known art and a rotor having poles wound when winding a wire;

[0063] FIG6 is a perspective view of a winding machine (coil winding machine) according to the invention;

[0064] FIG7 is a top view of the machine shown in FIG6;

[0065] FIG8 is a front view of the first part (defining the spindle) and the wound rotor of the machine shown in FIG6;

[0066] FIG9 is a side view, front view, and partial sectional view of the spindle part of the machine shown in FIG6 and FIG8;

[0067] FIG10 is a plan, top view, and partial sectional view of the spindle part of the machine shown in FIG6 and FIG8;

[0068] FIG11 is an isometric view of the spindle part of the machine shown in FIG6 and FIG8;

[0069] FIG12 is a perspective view and front view of the second part of the machine showing the defined tailstock of FIG6;

[0070] FIG13 is a vertical sectional view of the tailstock of the machine shown in FIG6 and FIG12;

[0071] FIG14 is a cross-sectional plan view of the tailstock of the machine shown in FIG6 and FIG12, considered on the plane of section B-B of FIG13;

[0072] Figure 15 is an equidistant and vertical (axial) cross-sectional view of the tailstock of the machine shown in Figures 6 and 12;

[0073] Figures 16-19 are cross-sectional plan views of four corresponding configurations of the machine shown in Figure 6 during the step of depositing wires onto the poles of the rotor of the motor;

[0074] Figures 20 to 23 are vertical (axial) cross-sectional views of four corresponding configurations of the tailstock of the motor shown in Figures 6, 12, and 16 to 19 during the step of depositing wires onto the poles of the rotor of the motor. Detailed Description

[0075] Figure 1 shows a rotor 1 with wound poles, intended for assembling a motor.The rotor 1 includes a body 2 and a plurality of pole pieces 4. The body 2 has a shaft 3 for rotation on a rotation axis Z. The plurality of pole pieces 4 extend radially from the rotation axis 3 and define rotor slots 5 between the pole pieces 4.

[0076] The body 2 of the rotor 1 is a set of stacked metal laminations: reference numeral 6 indicates a single lamination, particularly the last lamination at the top. A winding 7 of wire 8 (e.g., copper wire) is made around each pole piece 4.

[0077] The rotor 1, as shown in FIG1, can be formed using a pin winding technique or an in-slot technique.

[0078] FIG5 shows a winding machine (coil winding machine) 9 according to known technology, and is provided with two wire guide pins 10, which are fed with wire 8 and can move around the pole pieces 4 and in the rotor slots 5 for depositing wire according to a desired layered pattern, thereby for manufacturing the winding 7. The vertical movement (axial and parallel to the Z-axis of rotor 1) of the wire guide needle 10 is synchronized with the alternating rotational movement of the rotor body 2 about the Z-axis.

[0079] Figures 2-4 show a portion of rotor 1, particularly the pole pieces 4 of rotor 1, while the winding 7 is manufactured in the needle machine 9 shown in Figure 5. As can be seen in Figures 2-5, at the pole pieces 4, the rotor body 2 is axially compressed by vises 11, the task of which is to axially press (axis Z) the metal laminations 6 that define the rotor body 2. As can be seen from Figure 5, all the pole pieces 4 of rotor 1 are combined with the corresponding vises 11 so that the aforementioned umbrella effect does not occur when winding in the needle machine 9. Each vise 11 is provided with two jaws 12' and 12'", which can move away from each other in the axial direction to open the vise 11 and can move toward each other to tighten the vise 11. The tightening force is applied by a spring positioned inside the vise 11, and the preload of the spring can be adjusted by screws 13. As described with reference to the prior art, before the rotor 1 is placed into the machine, i.e., before the body 2 of the rotor 1 is positioned in the winding machine 9 and the winding of the pole piece 4 with the wire 8 continues, the vise 11 is initially open, so each vise 11 is assembled (pre-assembled) on the pole piece 4 of the rotor 1. At the end of this operation, whenever the rotor 1 completes the winding 7, the rotor 1 is removed from the machine 9, and the vise 11 is opened and removed from the body 2 of the rotor 1.

[0080] It can be noted by observing Figures 2-5 that the size of the vise 11 cannot be ignored: the size does not prevent the wire guide pin 10 from being inserted into the rotor slot 5, and therefore does not impair the winding performed in the needle machine (e.g., machine 9), but is incompatible with the winding technique defined by the in-slot technique, which provides the insertion of a metal wire guide cap into the rotor slot and the rotation of the body 2 of the rotor on an axis orthogonal to the axis Z.

[0081] This is where the invention comes into play, which relates to an in-slot winding method and machine that allows for the formation of high-quality windings on a rotor with winding poles without the use of a vise 11.

[0082] Figures 6 and 7 show, as a whole, an automatic winding machine (coil winding machine) 14 according to the invention for in-slot winding.

[0083] The automatic winding machine 14 (hereinafter simply referred to as machine 14 or winding machine 14) comprises three main units: a spindle unit 15, a tailstock unit 16 (for simplicity, they will be referred to as spindle 15 and tailstock 16), and a feed unit 17 for feeding the wire.

[0084] The feed unit 17 includes a wire guide tube 18, which is supplied with wire by a wire tensioning device 19, the task of which is to maintain the wire at a nominal tension throughout the winding process on the rotor 1. It can be noted that the feed unit 17 is located above the main shaft 15 and the tailstock 16, such that the wire guide tube 18 is more or less aligned with the end of the tailstock 16.

[0085] The main shaft 15 and the tailstock 16 face each other from opposite sides relative to the rotor 1, or in other words, are arranged radially opposite each other with respect to the rotation axis Z of the rotor 1. The main shaft 15 is provided with a fork 19, in which the body 2 of the rotor 1 is locked while the wire is wound. The fork 19 rotates by the main shaft 15 about an axis Y orthogonal to the rotation axis Z of the rotor 1, which is defined as the proximity axis Y. The rotation of the rotor 1 about the axis causes the pole piece 4 facing the tailstock 16 from time to time to rotate like a spool, and the wire can be wound on the spool according to the desired number of coils and the desired layered pattern. Obviously, once the pole piece 4 has been completed, that is, the winding 7 has been completed on it, the rotor 1 rotates about the axis Z relative to the fork 19 so that the new pole piece 4 faces the tailstock and the corresponding winding begins. Therefore, the rotation of the rotor relative to the fork 19 about the axis Z is intermittent, and whenever the rotor 1 does not rotate about the axis Z, it rotates about the axis Y to perform winding on one of its pole pieces 4, and vice versa, until all windings 7 are completed. The rotation of the fork 19 and thus the rotation of the rotor 1 about the axis Y is controlled by the motor M1.

[0086] The tailstock 16 is provided with different functions, as will be described below. Specification 7 / 12 pages 11 CN 121014158 A

[0087] The tailstock 16 is provided with a metal cap 20 for guiding the wires 8 on the pole pieces 4 during the winding process. For this purpose, the wire guide cap 20 (hereinafter referred to as cap 20) can move along the axis Y, thereby moving radially relative to the rotation axis 3 of the rotor 1, and the wire guide cap 20 moves alternately in two directions (also relative to the same tailstock 16) to insert into the rotor slot 5, thereby closing the pole pieces 4 and guiding the wires 8 as the rotor 1 rotates about the axis Y, thereby forming the desired layering.

[0088] Figure 8-11 shows the spindle 15 in more detail.Specifically, Figure 8 shows a front view of the spindle 15 with the rotor 1 inserted into the fork 19, as seen from the tailstock. Figure 9 shows the spindle 15 in side, front, and partial sectional views, with the rotor 1 locked in the fork 19. Figure 10 shows the spindle 15 in a top plan view and partial sectional view, with the rotor 1 locked in the fork 19. It can be noted that the openable fork 19 tightly holds the rotor 1 to prevent undesirable movement of the rotor 1 relative to the same fork 19. Once the winding 7 on the pole 4 shown in Figure 8 has been completed (pole 4 facing the tailstock 16), the fork 19 is partially opened to allow the rotor to rotate about axis Z, thereby bringing the new pole 4 into the position shown in Figure 8, closing the fork 19 again and starting a new winding 7 of the conductor. Figure 11 is a perspective view of the spindle 15 and the rotor 1. In addition to the opening fork 19, the main shaft 15 is also provided with a linear actuator 21, the task of which is to lock the rotor 1 to the fork 19 by fastening the rotor to the end of the fork 19. The rotation about the axis Y is shown by the arrows in Figures 8 and 11, and can be counterclockwise as shown, or it can be clockwise.

[0089] In summary, the tailstock 16 is therefore movable toward and away from the main shaft 15 along the axis Y, and the rotor 1 is positioned on the main shaft 15, the axis of rotation Z of the rotor 1 is orthogonal to the axis Y, and the rotor 1 rotates precisely about the axis Y in a clockwise or counterclockwise direction.

[0090] Figures 12-15 show the tailstock 16. In particular, Figure 12 is a perspective view of the tailstock 16, which is shown on the side facing the main shaft 15 and therefore toward the rotor 1 and one of its pole pieces 4, on which the wire will be deposited. As can be noted, the metal cap 20 is mounted on the tailstock 16 and is movable along the axis Y toward and away from the main shaft 15 together with and / or relative to the same tailstock 16. The cap 20 is specifically shaped to be inserted into the rotor slot 5 of the rotor 1, thereby surrounding the pole piece 4 and engaging the two rotor slots 5 located to the right and left of the pole piece 4. For this purpose, the cap 20 has a height range parallel to the main range of the rotor 1.

[0091] The tailstock 16 is movable between a retracted position completely disengaged from the rotor 1 and a forward position defining an abutment position, in which the tailstock abuts against the pole piece 4 of the rotor 1 shown in Figures 8 and 11, i.e., holding the accessible pole piece 4 in the direction Y via the fork 19.

[0092] The cap 20 is movable between a forward position and a retracted position, the forward position corresponding to the cap 20 being inserted to the maximum extent into the rotor slot 5 of the rotor 1, and the retracted position corresponding to the cap 20 being inserted to the minimum extent into the rotor slot 5 of the rotor 1.

[0093] The winding of the wire 8 on the pole piece 4 occurs when the cap 20 is inserted into the rotor slot 5: by properly controlling the alternating movement of the cap 20 on the axis Y between the forward position and the retracted position, the desired layering of the wire 8 on the pole piece 4 is achieved, that is, the desired shape of the winding 7 is achieved.

[0094] The tailstock 16 also includes a vise 22 integrated therein (particularly in the insertion cap 20), and the vise 22 has the task of pressing the body 2 of the rotor 1 at the pole piece 4 when wound.

[0095] The vise 22 includes two jaws 23 and 24 that are movable between a proximal position and a distal position for pressing the body 2 of the rotor 1 and disengaging the body 2 of the rotor 1, respectively. As can be noted in FIG12, the jaws are shaped to be concave to complement the convexity of the radially outer surface of the pole piece 4 of the rotor 1, thereby allowing the tailstock 16 to abut against the pole piece 4, and consequently the jaws 22, 23 to abut against the pole 4.

[0096] Once the rotor slot 5 extends radially relative to the shaft 3 of the rotor 1, the shape of the cap 20 is modifiable to allow it to be inserted into the slot 5, i.e., to fit its shape. Specifically, the cap 20 is defined by two halves 20' held on opposite portions relative to the vise 22 and 20” of the specification, page 8 / 12, CN 121014158 A. The two halves 20' and 20” of the vise 20 can move away from and towards each other, and move relative to the vise 22 at halfway between them, such that when the cap 20 moves from the retracted position to the forward position, the two halves 20' and 20” move accordingly closer to the angle intercepted by the center of the winding 7 on the pole piece 4, and vice versa, when the cap 20 moves from the forward position to the retracted position, the halves 20' and 20” move away.

[0097] Therefore, the winding 7 is formed on the pole piece 4 of the rotor 1 by combining the following actions:

[0098] - Actions for rotating the main shaft 15 and the rotor 1 about the axis Y;

[0099] - Actions for moving the cap 20 radially forward and backward along the axis Y relative to the rotation axis X of the rotor 1;

[0100] - Actions for opening and closing the cap 20, i.e., actions for opening and closing the halves 20' and 20" of the cap 20.

[0101] The operation of the tailstock 16, especially the operation of the cap 20 and the vise 22, will be described in detail below with reference to the remaining figures.

[0102] Figure 13 shows a vertical cross-sectional view and an elevation view of the tailstock 16, i.e., a section considered in a vertical plane passing through the rotation axis Z of the rotor 1 (before rotation about the axis Y), as shown in Figures 6-11. The section is also the plane of symmetry of the vise 20.

[0103] It can be noted that the vise 20 is provided with a drive shaft 25 arranged along the Y axis, which is used to drive the grippers 23 and 24. The drive shaft 25 has a first end that is inserted into the body of the tailstock 16 supported by a bearing, and a second wedge-shaped end for engaging the hinged quadrilateral lever system 27.This lever system 27 is hinged to both the body of the tailstock 16 and the jaws 23, 24, such that:

[0104] - the wedge end 26 is forcibly inserted (by the thrust applied by the actuator) into the lever system 27 to open the vise 20, i.e., the jaws 23, 24 are removed; the same result can be achieved using a toggle mechanism;

[0105] - the drive shaft 25 returns to its initial position to cause the vise 20 to close automatically, i.e., the vise 23, 24 are moved toward each other by a preloaded spring (not visible in FIG. 13).

[0106] This configuration allows the jaws 23, 24 to be held firmly against the lamination group 6 of the body 2 of the rotor 1 at the pole piece 4, thereby preventing the umbrella effect.

[0107] Since the tailstock 16 must rotate about the axis Y to perform the winding of the wire, the drive shaft 25 is mounted to be rotatable about the axis Y. The actuator controls the axial displacement of the drive shaft 25 on the axis Y, while rotation is imparted by a separate component, as described below, i.e., the drive shaft 25 is driven to rotate about the axis Y while the wire 8 is placed (or deposited).

[0108] The drive shaft 25 is coaxially inserted into the rotating shaft 28 of the cap 20, and its task is to drive the cap 20 to rotate about the axis Y, while the rotor 1 rotates about the same axis Y: during this rotation, the rotor 1 rotates integrally with the fork 19 and the cap 20 about the axis Y. Specifically, the rotating shaft 28 of the cap 20 also rotates the drive shaft 25 of the vise 22, specifying that the shaft 25 also slides within the shaft 28 to open and close the vise 20.

[0109] FIG14 shows the tailstock 16 on plane B-B of FIG13 in plan view, top view and partial sectional view; FIG15 shows the perspective view and vertical section (elevation) view of the tailstock 16. As can be observed, inside the cap 20, actuators 29 for actuating the two halves 20' and 20" of the cap 20 are located between the vise 22 and the body of the tailstock 16. The actuators 29 include guides or tracks 32 that are skewed relative to the Y-axis and tilted at an angle corresponding to the angle formed by the poles of the rotor being processed, as shown in the example, 60° (for six poles, 360° / 6 = 60°; for eight poles, the angle would be 360° / 8 = 45°). The guides 32 engage the corresponding guides 33 of the halves 20' and 20" of the cap 20. Axial movement of actuator 29 along axis Y causes displacement of guide 32, which applies thrust to guide 33 of the two halves 20' and 20" of the cap, thereby resulting in control of their opening and closing. In this way, cap 20 can be widened and narrowed to fit the available space depending on the position of rotor slot 5.

[0110] Figures 16-19 show, in chronological order, the movement for inserting cap 20 into rotor slot 5 of rotor 1 mounted on main shaft 15.Specifically, the accompanying drawings are plan and cross-sectional views of the winding machine 14, which are considered on a horizontal plane containing the axis Y and orthogonal to the axis Z.

[0111] In the configuration shown in FIG16, which can be defined as a standby configuration, the spindle 15 and the tailstock 16 face each other and are therefore far apart from each other along the axis Y. The tailstock 16 is in a retracted position, ready to abut against the rotor 1 held in place by the spindle 15, specifically locked between the fork 19 and the actuator 21. The rotor 1 is stationary in this configuration. A single pole piece 4 can be approached from the outside of the fork 19 for the tailstock 16, with the pole piece 4 facing the fork 19. Whenever needed, the rotor can be unlocked to allow it to rotate partially, and the rotor is locked again whenever a new pole piece 4 is aligned with the tailstock 16.

[0112] In the configuration shown in FIG. 17, which can be defined as an engagement configuration, the tailstock 16 is shown in an adjacent position: the body of the tailstock 16 is shifted forward toward the main shaft 15, and the two halves 20' and 20" of the cap 20 surround the end of the pole piece 4 furthest from the rotation axis 3 of the rotor 1; the vise 22 abuts against the outer surface of the pole piece 4, thus being complementary in shape to the outer surface of the pole piece 4. The rotor 1, the fork 19, and the tailstock 16 are all stationary. The vise 22 is open, i.e., the drive shaft 25 is in its forward position, the wedge end 26 is inserted into the lever system 27, i.e., the jaws 23 and 24 are open in the distal position. The jaw 23 is located above the metal lamination group 6 defining the body 2 of the rotor 1, and the jaw 24 is located below the same lamination group 6.

[0113] In the configuration shown in Figure 18, which can be defined as a pressing configuration, the vise 22 is closed, that is, the jaws 23 and 24 are brought closer together to secure the lamination group 6 that defines the body 2 of the rotor 1. Thus, the body 2 of the rotor 1 is pressed together at least at the pole piece 4 abutted against by the tailstock 16. The vise 22 is achieved by moving the drive shaft 25 of the vise 22 rearward relative to the body of the tailstock 16. Closure: This can be noticed by comparing Figures 17 and 18. The rearward movement of the drive shaft 25 also causes the wedge portion 26 to move rearward, resulting in the lever system 27 yielding to the return force applied by the spring (not shown) to bring the grippers 23 and 24 to the proximal position. In this configuration, the body 2 of the rotor 1 is compacted similarly to that shown in Figures 2-4 with respect to known technology, in this sense, the umbrella effect is prevented by not applying an external vise 11 to the pole piece 4, but by using a vise 22 integrated into the tailstock 16 of the winding machine and operated by the same actuator as the actuator of the tailstock 16 instead of an external actuator.

[0114] Once the body 2 of the rotor 1 has been compacted, the winding of the wire 8 begins.

[0115] In the configuration shown in Figure 19, which can be defined as a layered configuration, the machine 14 during winding is shown.Although rotor 1 is shown in the same position as in Figures 16-18, the reader should imagine it rotating clockwise or counterclockwise about axis Y: the rotor rotates about axis Y via main shaft 15, as previously described, while it remains locked between fork 19 and linear actuator 21. While the body 2 of rotor 1 rotates about axis Y, vise 22 remains fastened to pole piece 4 and rotates integrally with rotor 1 about axis Y. Therefore, as the body 2 of rotor 1 rotates, the body 2 cannot unfold in the axial direction (i.e., parallel to axis Z of rotor 1) due to the springback of lamination group 6. While the body 2 of rotor 1 rotates about axis Y, tailstock 16 is displaced alternately in two directions along the same axis Y, thereby determining that metal cap 20 is inserted into rotor slot 5, which defines pole piece 4, with wires then wrapped laterally around pole piece 4.

[0116] The alternating movement for inserting / removing cap 20 into rotor slot 5 is indicated by arrow W in Figure 19. This is not a simple translational movement, because the rotor slot 5 has a substantially radial range: the two halves 20' and 20' of the cap 20 must also move toward and away from each other, and thus toward and away from the axis Y, in order to accommodate the rotor slot 5 during the forward movement of the cap 20. This serves a dual purpose: to prevent interference with the body 2 of the rotor and to follow the path required to bring the conductor 8 to the desired layering.

[0117] Therefore, the cap 20 undergoes different movements: forward and backward movements on the axis Y, opening and closing movements, i.e., movements toward and away from halves 20' and 20”, and rotational movements about the axis Y, taking into account that the cap 20 also rotates integrally with the body 2 of the rotor 1 during winding, just like the vise 22.

[0118] Observing FIG19, the reader should see that the wire 8 is continuously fed and pre-tensioned by the feed unit 17 through the guide tube 18, and thus extends orthogonally to the plane of FIG19. During winding, the wire 8 abuts against the cap 20, which guides the wire 8 to deposit on the rotating electrode 4. Therefore, the forward and backward movement of the cap 20 along the axis Y causes the wire 8 to layer. In FIG19, the wire 8 is shown in cross-section (not to scale for illustrative purposes).

[0119] Once the winding 7 is completed, the machine 14 stops rotating the main shaft 15, brings back the rotor 1 with the vertical axis Z, retracts the tailstock 16, and thus removes the cap 20 from the rotor slot 5 and opens the vise 22. At this time, the rotor 1 rotates about the axis Z so that the other pole piece 4 interacts with the tailstock 16 as described above, thereby forming the winding 7.

[0120] The above operation is repeated for all pole pieces 4 until the rotor 1 is completed.

[0121] Figures 20 to 23 are vertical cross-sectional views, i.e., front views, of a portion of the tailstock 16 and the main shaft 15 in the four configurations shown in Figures 16 to 19.In other words, these figures correspond in pairs: Figure 16 corresponds to Figure 20, Figure 17 corresponds to Figure 21, Figure 18 corresponds to Figure 22, and Figure 19 corresponds to Figure 23, and four corresponding operational steps are shown in chronological order: standby, engagement, pressing, and layering.

[0122] In Figure 20, the machine 14 is shown in a standby configuration, with the drive shaft 25 of the vise 22 in a forward position: the vise 22 is open, with the jaws 23 and 24 opened by the force applied by the lever system 27, i.e., on the distal side, the lever system 27 then receives the thrust of the wedge-shaped end 26 of the drive shaft 25. In this configuration, the distance between the jaws 23 and 24 is sufficient to allow the lamination group 6 defining the body 2 of the rotor 1 to be inserted into the pole piece 4 between them. The tailstock 16 is spaced apart from the main shaft 15 and the rotor 1, but is ready to be juxtaposed.

[0123] Figure 21 shows the machine 14 in an engaged configuration: the tailstock 16 advances along the Y-axis until the vise 22 abuts against the side surface 4' of the pole piece 4, which is stationary with the spindle 15. The jaws 23 and 24 surround the metal lamination group 6.

[0124] Figure 22 shows the machine 14 in a pressing configuration of the rotor 1: the drive shaft 25 of the vise 22 is pulled back from the previously shown position (by an actuator), resulting in the wedge end 26 being disengaged from the lever system 27. The closing of the vise 22 is determined by no longer counteracting the action of the spring, i.e., the jaws 23 and 24 shifting to a proximal position and the corresponding pressing of the lamination group 6, as previously described. The spindle 15 and tailstock 16 are now stationary along the Y-axis, and the body 2 of the rotor 1 is not subjected to the umbrella effect.

[0125] Figure 23 shows the machine 14 in a layered configuration (i.e., during winding). The spindle 15 and tailstock 16 rotate integrally (synchronously) about the Y-axis. The vise 22 remains clamped to keep the body 2 of the rotor 1 pressed down. The wire 8, pre-tensioned by the wire tensioner 19 and from the feed unit 17, is continuously fed to the tailstock 16, particularly to the cap 20. To achieve the desired layering, with fewer loops near axis Z and more loops in the sector 4 away from axis Z, as shown in Figure 23, the tailstock 16 and / or cap 20 move in both directions along axis Y to guide the wire 8, while the rotor 1 continues to rotate about axis Y and the vise 22 keeps the body 2 pressed down. During the alternating movement of the cap 20 along axis Y, the vise 22 always remains clamped to the body 2 of the rotor 1 to prevent umbrella effects. The cap 20 moves in both directions along axis Y and rotates about axis Y simultaneously with the spindle 15 and the rotor 1. This process is repeated once winding 7 is complete until all windings of the rotor 1 are complete.

[0126] Therefore, the winding machine 14 allows for in-slot winding of the rotor 1, thus providing the insertion of the cap 20 into the rotor slot 5 between the pole pieces 4 without the need for an external vise, the size of which would make it impossible to abut the tailstock 16 against the side surface 4' of the pole piece 4. Instead, a vise 22 integrated into the tailstock is used, i.e., a vise 22 positioned inside the cap 20 and operated by an actuator shared with the cap 20.

[0127] The integration of the vise 22 and the cap 20 provides the use of a drive shaft 25 for operating the vise 22 (by means of a spring and lever system 27) and a rotation shaft 28 for the cap 20. Shafts 25 and 28 are coaxial with respect to axis Y, wherein the drive shaft 25 is within the rotation shaft 28, and the two shafts depend on each other: whenever the vise 22 is opened, the drive shaft 25 slides within the rotation shaft 28, i.e., translates therein. When the vise 22 is secured to the body 2 of the rotor 1, the two shafts 25, 28 rotate integrally.

[0128] By utilizing the internal volume of the cap 20, space can be made for the vise 22 without making the structure of the tailstock 16 too complex as described on pages 11 / 12 of the specification (CN 121014158 A), thus having the advantage of solving the umbrella effect problem in slot winding technology.

[0129] The solution of integrating the vise 22 inside the cap 20 is also feasible in an alternative embodiment of the winding machine, wherein the winding of the wire 8 is achieved by keeping the body 2 of the rotor 1 stationary on the spindle 15, that is, without rotating the body 2 of the rotor 1 about the axis Y, and therefore without even rotating the cap 20 and the vise 22, but by using a rotating system for feeding the wire 8, which rotates about the axis Y, to wind the wire 8 onto the cap 20, which guides the wire 8 on the pole piece 4. In this embodiment, which is not shown in the figure, the spindle 15 can simply be a non-rotating support, and the feed unit 17 rotates about the approximate axis Y to wind the wire 8 around the wire guide cap 20, which in turn controls the deposition path around the electrode 4 in the winding 7.Instruction manual page 12 / 12, page 16, CN 121014158 A, Figure 1; Instruction manual figure 1 / 12, page 17, CN 121014158 A, Figure 4; Instruction manual figure 2 / 12, page 18, CN 121014158 A, Figure 5; Instruction manual figure 3 / 12, page 19, CN 121014158 A, Figure 6; Instruction manual figure 4 / 12, page 20, CN 121014158 A, Figure 7; Instruction manual figure 5 / 12, page 21, CN 121014158 A; Instruction manual figure 6 / 12, page 22, CN 121014158 A; Instruction manual figure 7 / 12, page 23, CN 121014158 A; Instruction manual figure 8 / 12, page 24, CN 121014158 A; Instruction manual figure 9 / 12, page 25, CN 121014158 A, Figure 19; Instruction manual figure 10 / 12, page 26, CN 121014158 A Instruction manual, Figures 11 / 12, Page 27 CN 121014158 A Instruction manual, Figures 12 / 12, Page 28 CN 121014158 A.

Claims

1. A method for manufacturing a winding (7) of wires (8) on pole pieces (4) of a rotor (1) of an electric motor using in-slot technology, wherein, During winding, the wire (8) is guided by a wire guide cap (20) that can move in the rotor slots (5), the pole piece (4) extends between the rotor slots (5), wherein the body (2) of the rotor (1) is axially pressed by a device (22) inside the wire guide cap (20).

2. The method according to claim 1, wherein, The main body (2) of the rotor (1) is composed of a stacked group of metal laminations (6), and the axial pressing parallel to the rotation axis (Z) of the rotor (1) applied when the wire (8) is wound around the pole piece (4) keeps the height of the group of metal laminations (6) to a minimum by compensating for the possible elasticity of the connection between the metal laminations (6).

3. The method according to claim 1 or 2, wherein, Pressing is applied to the conductor (8) throughout the winding process on the electrode (4).

4. The method according to any one of the preceding claims, wherein, The conductor (8) is wound onto the electrode (4) using an automatic winding machine (14) in one of the following ways: - By keeping the body (2) of the rotor (1) stationary and simultaneously moving the wire guide cap (20) alternately in two directions along the proximal axis (Y) in the rotor slot (5), and by winding the wire (8) around the wire guide cap (20), this in turn provides the means to deposit the wire onto the electrode (4), or - By moving the wire guide cap (20) alternately in two directions along the proximity axis (Y) in the rotor slot (5), and by rotating the main shaft (15) of the body (2) together with the rotor (1) and the wire guide cap (20) and the pressing device (22) integrated into the wire guide cap (20) simultaneously and integrally on the proximity axis (Y).

5. The method according to claim 4, wherein, The rotor (1) has its axis of rotation (Z), and in the automatic winding machine (14), the wire guide cap (20) is readily displaced in a controlled manner in two directions along the approach axis (Y) and radially relative to the axis of rotation (Z) of the rotor (1), and wherein the dimensions of the wire guide cap (20) are designed to substantially surround the pole piece (4) of the rotor (1), and wherein the pressing device (22) is a vise integrated into the wire guide cap (20).

6. The method according to claim 5, wherein: - While winding the wire (8), the vise (22) continuously applies axial pressure to the body (2) of the rotor (1), and the rotor (1), the wire guide cap (20) and the vise (22) rotate integrally, i.e. synchronously, on the near axis (Y); - Once wound, whenever the rotor (1) remains stationary, the wire guide cap (20) is removed from the pole piece (4), i.e., detached from the rotor (1), and the vise (22) opens to detach from the rotor (1).

7. The method according to any one of the preceding claims, wherein, The axial pressure is applied to the body (2) of the rotor (1) at the edge of the pole piece (4).

8. The method according to any one of the preceding claims, wherein, The movement of the wire guide cap (20) depends on the activation or deactivation of the pressing device (22).

9. The method according to any one of the preceding claims, wherein, The axial pressure applied by the pressing device (22) to the body (2) of the rotor (1) is adjustable.

10. A slot-type winding machine (14) for forming a winding of conductors (8) on the pole pieces (4) of the rotor (1) of an electric motor, comprising: - A main shaft or support (15), wherein the main shaft or support (15) is provided with a device (19, 21) for supporting the main body (2) of the rotor (1); - Tailstock (16), which is movable relative to the main shaft (15) along the approach axis (Y) between a proximal position of the body (2) for engaging the rotor (1) supported by the main shaft (15) and a distal position of the body (2) for disengaging from the rotor (1); - A unit (17) for feeding the wire (8); The tailstock (16) includes a wire guide cap (20) which is movable relative to the main shaft (15) between a position in which the wire guide cap (20) is most inserted into the rotor groove (5) of the body (2) of the rotor (1) supported by the main shaft (15) and a minimum insertion or disengagement position, wherein the wire guide cap (20) does not engage the rotor groove (5) at the minimum insertion or disengagement position; This includes a pressing device (22) which is arranged inside the wire guide cap (20) and configured to press the body (2) of the rotor (1) axially.

11. The winding machine (14) according to claim 10, wherein, The pressing device (22) is adjustable to apply a calibrated axial pressure parallel to the rotation axis (Z) of the rotor (1) onto the body (2) of the rotor (1), in particular a pressure sufficient to counteract the elasticity of the body (2) of the rotor (1) and press the body (2) to a minimum height.

12. The winding machine (14) according to claim 10 or claim 11, wherein, The pressing device (22) can be operated throughout the winding process.

13. The winding machine (14) according to any one of the preceding claims, wherein, In use: - The main body (2) of the rotor (1) remains stationary in the main shaft or support (15), and the wire guide cap (20) moves alternately in two directions along the approach axis (Y) in the rotor slot (5), and the wire (8) is wound around the wire guide cap (8) by the feed unit (17), the wire guide cap (8) in turn providing a means to deposit the wire onto the electrode plate (4), or The wire guide cap (20) moves alternately in two directions in the rotor slot (5) along the approach axis (Y), and together with the main shaft (15) of the body (2) of the rotor (1) and the wire guide cap (20), as well as the pressing device (22) integrated into the wire guide cap (20), rotate simultaneously and integrally on the approach axis (Y).

14. The winding machine (14) according to claim 13, wherein, The main body (2) of the rotor (1) is supported by the spindle or support (15), wherein the rotation axis (Z) of the rotor (1) is orthogonal to and intersects the approach axis (Y), and wherein the wire guide cap (20) is readily displaced in two directions along the approach axis (Y), and wherein the dimensions of the wire guide cap (20) are designed to substantially surround the pole piece (4) of the rotor (1), and wherein the pressing device (22) is a vise integrated into the wire guide cap (20).

15. The winding machine (14) according to claim 14, wherein, The spindle (15), together with the main body (2) of the rotor (1), the wire guide cap (20), and the vise (22) integrated into the wire guide cap (20), can rotate integrally on the approach axis (Y).

16. The winding machine (14) according to claim 15, wherein, The rotation of the wire guide cap (20) and the vise (22) on the proximity axis (Y) depends on the activation of the vise (22) on at least one edge of the pole piece (4) of the body (2) of the rotor (1).

17. The winding machine (14) according to any one of the preceding claims, wherein, The pressing device (22) is a vise, which includes two jaws (23, 24) that are radially movable relative to the approach axis (Y) between a distal position corresponding to the opening of the vise (22) and a proximal position corresponding to the closing of the vise (22).

18. The winding machine (14) according to claim 17, comprising an actuator for the vise (22), the actuator further comprising a drive shaft (25) extending on the proximal axis (Y), a lever system (27) constrained to the jaws (23, 24), and at least one spring that continuously applies a return force on the jaws (23, 24) to bring the jaws to a proximal closed position of the vise (22), and in, The drive shaft (25) slides on the proximity axis (Y) between an engaged position and a disengaged position of the lever system (27), in which the lever system (27) counteracts the action of the spring and holds the jaws (23, 24) in the distal open position of the vise (22), and in the disengaged position, the lever system (27) does not counteract the action of the spring and the jaws (23, 24) are in the proximal closed position of the vise (22).

19. The winding machine (14) according to claim 18, wherein, The wire guide cap (20) is mounted on a rotating shaft (28) that is rotatable on the proximity axis (Y), and the drive shaft (25) of the vise (22) is located inside the rotating shaft (28) of the wire guide cap (20) and is coaxial with the rotating shaft (28).

20. The winding machine (14) according to any one of the preceding claims, wherein, The wire guide cap (20) comprises two halves (20', 20”) arranged on opposite sides relative to the pressing device (22) and capable of moving radially away from and toward each other about the approach axis (Y) to change the size of the wire guide cap (20).

21. The winding machine (14) according to any one of the preceding claims, wherein, Whenever the pressing device (22) engages on the body (2) of the rotor (1), the wire guide cap (20) is able to move relative to the pressing device (22) along the approach axis (Y) to insert into the rotor slot (5).

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