Device for handling magnets when equipping a laminated core of a rotor of an electrical machine with magnets

Abstract

Device (10) for handling magnets when equipping a laminated core of a rotor of an electrical machine with magnets, with a magazine (11) for magnets, in which the magnets (12) are kept ready in the form of a magnet stack (13) with intermediate pieces (14) positioned between individual magnets (12), with a separating unit (15) for the magnets (12) which can be driven by an electric motor (16), via which, in a first partial movement of the separating unit (15), a magnet (12) is separated from the magnet stack (13) and removed from the magazine (11), and via which, in a subsequent second partial movement of the separating unit (15), which is subsequently followed by a first partial movement, an intermediate piece (14) is separated from the magnet stack (13) and removed from the magazine (11), characterized in that a control device (26) monitors an electrical characteristic of the electric motor (16) during each first partial movement of the separating unit (15), and then, if the electrical characteristic of the electric motor (16) is smaller than a threshold value during a respective first partial movement, concludes that the last magnet from the magnet stack is removed from the magazine (11).

Description

[0001] The invention relates to a device for handling magnets when equipping a laminated core of a rotor of an electrical machine with magnets.

[0002] An electrical machine has a rotor and a stator. The rotor of an electrical machine is also called the runner, and the stator of an electrical machine is also called the stator.

[0003] The rotor of an electrical machine consists of a rotor core and magnets held in magnetic pockets within the rotor core. The rotor core, with the magnets held in the rotor core, can be mounted on a rotor shaft.

[0004] Rotors of electrical machines are known in practice in which the magnets are housed radially inward by the rotor core. Such radially inwardly housed magnets are also referred to as buried magnets, which are arranged in corresponding magnetic pockets of the rotor core. Buried magnets are inserted into the magnetic pockets of the rotor core, viewed in the axial direction of the rotor core, to accommodate the magnets in the rotor core.

[0005] Furthermore, rotors of electrical machines are known in practice in which, in addition to or as an alternative to buried magnets, magnets are positioned radially outside adjacent to the rotor core. Such magnets, which are radially outside adjacent to the rotor core, are also referred to as surface magnets. The surface magnets are attached to the rotor core via an enveloping body, also known as a bandage.

[0006] During the production of a rotor core stack of a rotor of an electrical machine equipped with magnets, the magnets must be handled, in particular in such a way that magnets kept ready as a magnet stack are separated from the magnet stack in order to make the separated magnets available for subsequent assembly of the rotor core stack.

[0007] DE 10 2011 077 215 A1, DE 10 2013 217 732 A1, and US 2017 / 0 070 128 A1 each disclose devices with which magnets can be handled when equipping a rotor laminated core of an electrical machine with magnets. DE 10 2011 077 215 A1 discloses that the magnets are held ready as a magnet stack consisting of magnets with spacers arranged between the magnets. A separating unit can separate the magnets from the magnet stack and remove them from the magazine in a first partial movement of the separating unit. A second partial movement of the separating unit following the first partial movement, which is then followed by another first partial movement, allows an spacer to be separated from the magnet stack and removed from the magazine.The two partial movements are translational partial movements running in opposite directions to each other of a separating unit designed as a sliding unit.

[0008] In DE 10 2011 077 215 A1, the magnet stack is stored in a magazine in such a way that the magnet stack is horizontally aligned. The translational movement of the separating unit occurs perpendicular to this, in a vertical direction. This requires driving not only the separating unit, but also the magnet stack within the magazine, or rather, the magazine itself. Furthermore, monitoring the magazine—that is, determining whether there are still magnets in the magazine—is difficult.

[0009] CN 1 10 350 733 A and DE 10 2010 016 535 A1 disclose further prior art.

[0010] The object of the invention is to provide a novel device for handling magnets when equipping a laminated core of a rotor of an electrical machine with magnets.

[0011] A device for handling magnets when equipping a laminated core of a rotor of an electrical machine with magnets according to a first aspect of the invention is defined in claim 1.

[0012] According to this, a control device monitors an electrical characteristic of the electric motor during each initial partial movement of the separation unit. If the electrical characteristic of the electric motor is less than a threshold value during a respective initial partial movement, the control device concludes that the last magnet from the magnet stack has been removed from the magazine.

[0013] The first aspect of the invention makes it possible to determine, by monitoring an electrical parameter of the electric motor that drives the magnet separation unit, whether a magnet is still present in the magazine or whether the last magnet in a magnet stack is or has already been removed from the magazine. This can further improve the handling of the magnets, particularly with regard to automated refilling of the magnets.

[0014] Preferably, the control device monitors an electrical current or electrical power consumption of the electric motor as an electrical parameter. Monitoring the electrical current or electrical power consumption of the electric motor driving the separating unit is particularly suitable for determining whether the last magnet in the magnet stack is being removed from the magazine. If this is the case, the electrical current required by the electric motor or the electrical power consumption of the electric motor is lower than when only the penultimate magnet is being removed from the magazine, since when the last magnet is removed from the magazine, it is no longer attracted by the magnetic force of another magnet in the magnet stack.

[0015] According to an advantageous development, the device for handling magnets when equipping a laminated core of a rotor of an electrical machine with magnets has a testing device at a dispensing point for magnets separated from the magnet stack and removed from the magazine, in order to monitor the presence of a magnet in the dispensing point and preferably additionally a polarization direction of a magnet located in the dispensing point. This allows the handling of the magnets to be further automated. In particular, it is advantageous if the testing device checks the polarization direction in which a magnet is present in the dispensing point of the device according to the invention. On the one hand, information about the polarization direction can be provided to a user, and on the other hand, the magnets to be handled can be arranged in a defined manner in magnetic pockets of a rotor laminated core of a rotor of an electrical machine.

[0016] A device for handling magnets when equipping a laminated core of a rotor of an electrical machine with magnets according to a second aspect of the invention is defined in claim 6.

[0017] According to this, the direction of movement of the separating unit in the partial movements thereof is inclined relative to a horizontal support or base and thus the direction of movement of the separating unit, which runs perpendicular to the movement of the magnet stack in the magazine, relative to a horizontal support or base by at least 20°, preferably by 30° to 60°.

[0018] The second aspect of the invention has the advantage that the magnet stack or the magnets of the magnet stack can move forward within the magazine solely due to gravity, eliminating the need to separately drive the magnet stack or the magazine containing the magnet stack. Furthermore, an ergonomic removal position for the magnets is created in the area of ​​the dispensing point.

[0019] According to an advantageous development, the device for handling magnets when loading a laminated core of a rotor of an electrical machine with magnets comprises a punch that presses down on the magazine stack stored in the magazine from above, and / or a magnetic plate arranged below the magazine that attracts the magazine stack stored in the magazine. When the punch and / or the magnetic plate are present, the gravity-driven movement of the magnets or the magnet stack in the magazine is supported.

[0020] Preferred developments of the invention will become apparent from the dependent claims and the following description. Exemplary embodiments of the invention are explained in more detail, without being limited thereto, with reference to the drawings. Herein: Fig. 1 a perspective view of a device for handling magnets when equipping a laminated core of a rotor of an electrical machine with magnets together with a punch, Fig. 2 a perspective view of the device of the Fig. 1 with a cover removed and without a stamp, Fig. 3 a first cross section through the device of the Fig. 1, Fig. 2, Fig. 4 a second cross section through the device of Fig. 1, Fig. 2, Fig. 5 the stamp of the device of Fig. 1, Fig. 2 in perspective view, Fig. 6 a magnet stack in perspective view, Fig. 7 a slider of the device of Fig. 1, Fig. 2 in perspective view, Fig. 8 two different magazines of the device of Fig. 1, Fig. 2 in perspective view from above, Fig. 9 the magazines of the device of Fig. 8 in perspective view from below.

[0021] The invention relates to a device for handling magnets during the assembly of a rotor core of an electrical machine with magnets. The device according to the invention serves to separate the magnets held as a magnet stack and to prepare the separated magnets for subsequent handling.

[0022] Fig. 1 shows a perspective side view of a device 10 according to the invention for handling the magnets, wherein the device 10 comprises a magazine 11 in which magnets 12 in the form of a magnet stack 13 (see Fig. 6) with intermediate pieces 14 positioned between individual magnets 12.

[0023] The device 10 has a separating unit 15, which is designed as a translationally displaceable slide. This separating unit 15 is driven by an electric motor 16. Via a gear unit 17, the rotary movement of the electric motor 16 can be converted into a translational movement of the separating unit 15. In a first partial movement of the separating unit 15, specifically in a translational movement of the separating unit 15 in a first direction, a magnet 12 can be separated from the magnet stack 13 and removed from the magazine 11 with the aid of the separating unit 15—namely, the bottommost magnet 12 of the magnet stack 13.By means of a second partial movement of the separating unit 15 following this first partial movement, namely by means of a translational movement in an opposite second direction, an intermediate piece 14 can subsequently be separated from the magnet stack 13 and removed from the magazine 12, namely the lowest intermediate piece 14 in the magazine stack. Fig. 3 shows the device 10 after completion of the first partial movement of the displacement unit 15, wherein a separated magnet 12 removed from the magazine 11 is held ready in an output location 18 of the device 10. Here, the separated magnet 12 can be removed from the device 10 for subsequent handling, either manually or with the aid of a robot.

[0024] The respective separated magnet 12 is moved during its separation and transfer in the direction of the output point 18 within an output channel 19, which is defined in sections by a lower, lateral projection 20 of the magazine 11. Fig. 8 and Fig. 9 show perspective views of two different magazines 11, 11' with such projections 20, 20' for magnets with different dimensions, wherein the magazine 11' is designed for smaller magnets than the magazine 11. For the magnets with the smaller dimensions, which are kept ready as a magnet stack in the magazine 11', the projection 20' is made thicker in order to adapt the feed channel 19 to the dimensions of the magnets.

[0025] Section 20 of the Fig. 1 to 4 is covered by a magazine clamp 25, via which the magazine 11 can be fixed to the device 10. The magazine clamp 25 is preferably made of a ferromagnetic material.

[0026] As already explained above, the intermediate pieces 14 are removed from the magazine 11 during the second partial movement of the separating unit 13, wherein the intermediate pieces 14 removed from the magazine 11 are guided via a Fig. 2 visible guide body 21, which in Fig. 1 is covered by a cover 22, can be ejected via a side opening 23 into a collecting container 24.

[0027] As already explained, the separating unit 15, which is provided by a translationally displaceable slide, can be driven by the electric motor 16. According to a first aspect of the invention, a control device 26 monitors an electrical characteristic of the electric motor 16 during each first partial movement of the separating unit 15 and evaluates this electrical characteristic such that, if the electrical characteristic of the electric motor 16 is smaller than a threshold value during a respective first partial movement of the separating unit 15, it is concluded that the last magnet 12 from the magnet stack 13 is being separated and removed from the magazine 11.

[0028] If there is only one magnet 11 left in the magnet stack 13, this magnet does not have to be detached from another magnet of the magnet stack 13 against the magnetic force of attraction when it is removed from the magazine 11, so that when the last magnet 12 of the respective magnet stack 13 is removed from the magazine 11, the respective electrical characteristic of the electric motor 16 is smaller than when there are still several magnets 12 in the magnet stack 13 of the magazine 11.

[0029] As an electrical characteristic, the control device 26 preferably monitors the electrical current or the electrical power consumption of the electric motor 16 or a characteristic corresponding to the electrical current or the electrical power consumption.

[0030] According to an advantageous further development, it is provided that when the control device 26 detects that the last magnet 12 is removed from the magnet stack 13 held in the magazine 11, the control device 26 automatically requests a magazine change 11 or a filling of the magazine 11 with a new magnet stack 13 on the control side.

[0031] Preferably, in the area of ​​the dispensing point 18 of the device 10, there is a testing device 27, with the aid of which it can be monitored whether a magnet 12 is located in the area of ​​the dispensing point 18, and with which a polarization direction of a magnet 12 located in the dispensing point 18 can preferably also be detected.

[0032] This signal detected by the test device 27 can be used to further automate the handling of isolated magnets 12 when assembling a rotor core of a rotor of an electrical machine, for example to automatically position the magnets 12 in a defined installation position with a defined polarization direction in magnet pockets of a rotor core.

[0033] According to a second aspect of the invention, it is provided that the direction of movement of the singulating unit 15 in the partial movements thereof, which runs perpendicular to the magazine 11 and thus perpendicular to the magnet stack 13 accommodated in the magazine 11, is inclined relative to a horizontal support or base 28 for the device 10 by an angle of at least 20°, preferably by an angle of 30° to 60°.

[0034] This has the advantage that when the bottommost magnet 12 or the bottommost intermediate piece 14 is removed from the magazine 11, the remaining magazine stack 13 moves forward in the magazine 11 under the support of gravity and thus falls downwards, so that no separate drive is required for the magnet stack 13 or the magazine 11 containing the magnet stack 13. The partial movements of the separating unit 15 run perpendicular to the magnet stack 13. Thus, the first partial movement of the separating unit 15 when separating a magnet 12 preferably runs diagonally upwards. The opposite second partial movement of the separating unit 15 when separating an intermediate piece 14 runs diagonally downwards.

[0035] According to an advantageous further development, the gravity-assisted advancement of the magnet stack 13 in the magazine 11 is supported by a stamp 29 which projects at least partially into the magazine 11 and presses onto the magazine stack 13 from above, so that the stack then falls downwards in a defined manner.

[0036] Fig. Figure 5 shows this punch 29 of the device 10 in isolation, with a lower portion 30 thereof protruding partially into the magazine 11 and an upper portion 31, on which a handling handle 32 is formed, protruding from the magazine 11. A shoulder 33 formed between the portions 30, 31 limits the insertion depth of the punch 29 into the respective magazine 11.

[0037] The gravity-induced advancement of the magazine stack 13 accommodated in the magazine 11 can be supported alternatively or in addition to the punch 29 by positioning a magnetic plate 34 below the magazine 11 and below a movement path for a magnet 12 to be separated, said magnetic plate 34 attracting the magazine stack 13 in the magazine 11 and thus pulling it downwards.

[0038] Due to the interaction of the force of gravity acting on the magnet stack 13 together with the weight of the punch 29 acting from above on a first side of the magazine stack 13 and the magnetic plate 34 acting from below on an opposite second side of the magazine stack 13, a defined movement of the magazine stack 13 when removing a magnet 12 or intermediate piece 14 from the magnet stack 13 can be ensured in a particularly advantageous manner without a drive for the magazine stack 13.

[0039] In Fig.7 shows the displacement unit 15 designed as a slider in isolation. It has a rod-like base body 35 with a shoulder 36 formed at one end of the base body 35. An edge 37 formed between the base body 35 and the shoulder 36 serves to separate the intermediate pieces 14 of the magnet stack 13 during the second partial movement of the separating unit 15 designed as a slider. An end face 38 of the shoulder 36 opposite this edge 37 serves to separate a magnet 12 from the magnet stack 13.

[0040] The device 10 according to the invention therefore has a separating unit 15, which is preferably designed as a translationally displaceable slide, wherein in a first partial movement of the separating unit 15 a magnet 12 can be removed from the magazine 11 and in a second opposite partial movement of the separating unit 15 an intermediate piece 14 can be removed from the magazine 11.

[0041] The separation unit 15 is driven by an electric motor 16, wherein an electrical characteristic of the electric motor 16 is monitored to determine whether a last magnet 12 is separated from the magnet stack 13 and removed from the magazine 11. If this is the case, a refill of the magazine 11 with a magnet stack 13 or a replacement of the magazine 11 can be triggered depending on this.

[0042] The direction of movement of the separating unit 16 in the partial movements thereof is preferably inclined relative to a horizontal base or support 28 by at least 20°, preferably between 30° and 60°, preferably between 30° and 50°, wherein the direction of displacement of the separating unit 15 runs perpendicular to the orientation of the magnet stack 13 in the magazine 11 and thus perpendicular to the gravity-induced advancement of the magnet stack 13 in the magazine 11.

[0043] The rotor core of an electrical machine's rotor to be assembled is, in particular, a rotor core of a permanent magnet synchronous machine, in which the magnets to be arranged in the magnet pockets of the rotor core are permanent magnets. Permanent magnets 12 are then provided in the magnet stack 13. List of reference symbols 10 Device 11 Magazine 12 Magnet 13 magnet stacks 14 Intermediate piece 15 Separation unit 16 Electric motor 17 Gear unit 18 Issue point 19 output channels 20, 20' lead 21 guide bodies 22 Cover 23 Opening 24 collection containers 25 magazine clamp 26 Control device 27 Test facility 28 Base 29 stamps Section 30 Section 31 32 Handling handle 33 paragraph 34 magnetic plate 35 basic bodies 36 paragraph 37 edge 38 frontal area

Claims

[1] Device (10) for handling magnets when equipping a laminated core of a rotor of an electrical machine with magnets, with a magazine (11) for magnets, in which the magnets (12) are kept ready in the form of a magnet stack (13) with intermediate pieces (14) positioned between individual magnets (12), with a separating unit (15) for the magnets (12) which can be driven by an electric motor (16), via which, in a first partial movement of the separating unit (15), a magnet (12) is separated from the magnet stack (13) and removed from the magazine (11), and via which, in a subsequent second partial movement of the separating unit (15), which is subsequently followed by a first partial movement, an intermediate piece (14) is separated from the magnet stack (13) and removed from the magazine (11), characterized by , that a control device (26) monitors an electrical characteristic of the electric motor (16) during each first partial movement of the separating unit (15), and then, if the electrical characteristic of the electric motor (16) is smaller than a threshold value during a respective first partial movement, concludes that the last magnet from the magnet stack is removed from the magazine (11). [2] Device (10) according to claim 1, characterized by that the control device (26) monitors an electrical current or an electrical power consumption of the electric motor (16) as an electrical characteristic variable. [3] Device (10) according to claim 1 or 2, characterized by that the control device (26) requests a magazine change or the filling of the magazine (11) on the control side when it detects that the last magnet from the magnet stack (13) is removed from the magazine (11). [4] Device (10) according to one of claims 1 to 3, characterized bya testing device (27) at a dispensing point (18) for magnets (12) separated from the magnet stack (13) and removed from the magazine (11) in order to monitor the presence of a magnet (12) in the dispensing point (18). [5] Device (10) according to one of claims 1 to 4, characterized by that the testing device (27) further detects a polarization direction of a magnet (12) located in the output point (18). [6] Device (10) for handling magnets when equipping a laminated core of a rotor of an electrical machine with magnets, with a magazine (11) for magnets, in which the magnets (12) are kept ready in the form of a magnet stack (13) with intermediate pieces (14) positioned between individual magnets (12), with a separating unit (15) for the magnets (12) which can be driven by an electric motor (16), via which, in a first partial movement of the separating unit (15), a magnet (12) is separated from the magnet stack (13) and removed from the magazine (11), and via which, in a subsequent second partial movement of the separating unit (15), which is subsequently followed by a first partial movement, an intermediate piece (14) is separated from the magnet stack (13) and removed from the magazine (11), characterized by , that the direction of movement of the separating unit (15) in the partial movements thereof is inclined by at least 20° relative to a horizontal support or base. [7] Device (10) according to claim 6, characterized by that the direction of movement of the separating unit (15) is inclined by 30° to 60° relative to the horizontal support or base. [8] Device (10) according to claim 6 or 7, characterized bya stamp (29) which presses from above onto the magnet stack (13) held in the magazine (11). [9] Device (10) according to one of claims 6 to 8, characterized by a magnetic plate (34) arranged below the magazine (11) which attracts the magnet stack (13) accommodated in the magazine (11). [10] Device (10) according to one of claims 6 to 9, characterized by that the same is further developed according to one of claims 1 to 5.

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