WO2021104956A1

WO2021104956A1 - Positioning device for copper rods

Info

Publication number: WO2021104956A1
Application number: PCT/EP2020/082469
Authority: WO
Inventors: Felix BROSA; Dennis Pietsch; Lutz Dreyer
Original assignee: Thyssenkrupp System Engineering Gmbh; Thyssenkrupp Ag
Priority date: 2019-11-29
Filing date: 2020-11-18
Publication date: 2021-06-03
Also published as: DE102019218599A1; DE102019218599B4

Abstract

The invention relates to a positioning device for peripherally positioning a plurality of copper rods about a central axis M defining an axial direction, said copper rods being substantially U-shaped and having a first leg portion and a second leg portion.

Description

Positioning device for copper rods

The invention relates to a positioning device for circumferentially positioning a plurality of copper rods around a central axis M, which describes an axial direction A, wherein the copper rods are essentially U-shaped with a first leg section and a second leg section.

In the manufacture of electrical machines, such as electric motors or generators, the aim is to simplify the assembly process and at the same time to improve the quality parameters during the assembly process. A distinction must be made here between stator elements and rotor elements manufactured using winding technology or manufactured using hair-pin technology. The hair-pin technology offers the possibility of increasing the power density of electric motors that are to be used in motor vehicles. In hair-pin technology, specially bent copper rods, which because of their shape are also referred to as hair-pins, are inserted into axially extending and internally or externally arranged receiving grooves of the stator element or rotor element.

In the course of the following description, the term copper rod is used and the English term hair pin is dispensed with. Copper rods can be shaped differently. First of all, a distinction must be made between U-shaped bent copper rods which have two essentially parallel leg sections which are connected to one another by a transverse section. When the copper rods are in the assembled state, the two leg sections are inserted into the receptacles of the stator element or rotor element. In addition to the U-shaped, there are I-shaped copper rods, which therefore only form a leg section and can have some kind of bend above the straight leg section. An I-shaped copper rod is inserted into a groove in the stator element or rotor element and protrudes freely upwards in order to be connected there in accordance with the circuit diagram.

The U-shaped copper rods can in turn be differentiated into a variant, the leg sections of which, when plugged in, lie on the same radii or diameters in relation to the central axis or axis of rotation of the stator element or rotor element, and in a variant, the leg sections of which in the plugged-in state on different Radii or diameters of the stator element or rotor element lie. The copper rods, which are placed on different radii, can in turn be divided into a variant that is placed on adjacent layers or within a level and a variant that is placed on non-adjacent layers, as from one level to another level to be plugged. The term level can best be explained from the point of view of the copper rod variant, which is bent into a U-shape and is plugged into the stator element or rotor element on different and immediately adjacent radii. Here, the radius on which one of the legs is plugged is referred to as a layer. The other of the two leg sections of a U-shaped copper rod is consequently located on the adjacent radius in the stator element or rotor element, so that this adjacent diameter forms another “layer”. Together, these two “layers” are referred to as “level” or stator “level”. The previously mentioned U-shaped copper rods, which are placed on the same radii, are consequently placed within a layer.

In recent times, increasing efforts have been made to develop hair-pin technology from a predominantly dog-like or semi-automatic production to a largely automated production. These assembly methods are very time consuming. Due to the high demands on the positional accuracy of the components combined with low component tolerances, dog-like or semi-automatic production leads to high cycle times and, with a certain probability, to damage to the components, which results in a high reject rate. The manufacture of rotor elements using hair-pin technology has been known for some time, as is described, for example, in US Pat. No. 1,555,931. Furthermore, US Pat. No. 1,661,344 describes an assembly device for producing rotor elements using hair-pin technology, with at most a semi-automatic assembly being able to be carried out with this. From a structural point of view, the assembly process can be divided into

1. A prepositioning, in which the first thing to do is to arrange the individual copper rods both relative to one another and as a whole circumferentially. Here, the copper rods have not yet the previously described overlapping position zueinan that they must later have in the stator element or rotor element;

2. Positioning by means of a positioning device to which the copper rods are passed in the pre-posited arrangement and via which the copper rods are brought into the overlapping position and

3. the actual assembly process, in which the copper rods are inserted into the stator element or rotor element to be fitted by means of a further Montagevor device.

Since there is a short cycle time in the assembly process when as many copper rods as possible are inserted into the corresponding grooves of the stator element or Rotorele element at the same time, it would be desirable to ensure the simplest possible handling of the copper rods and the totality of the for to assemble the equipping of a stator element or rotor element. One used for this The device must therefore allow a simple and damage-free arrangement of the copper rods, the copper rods in this arrangement expediently not yet overlapping, but rather the leg sections of each copper rod are arranged in a radial direction relative to one another on a central axis M, the copper rods in their entirety are arranged circumferentially around this central axis M. The arrangement can be referred to as a fanned-out arrangement. Only with the positioning device provided for the positioning are the copper rods positioned with respect to one another in such a way that adjacent copper rods overlap and the entirety of the copper rods is put together to form a basket. Regarding the positioning device, reference is made to the German patent application DE 102016221 355 A1 of the same reporter.

With this positioning device, it is easily possible to transfer U-shaped copper rods, which are inserted into the stator element or rotor element in two adjacent layers to one level, to a rotating basket or wire basket in an overlapping position, which can also be referred to as screwing. However, this device is not suitable if, in addition to this copper rod variant, the special variants of the copper rods described above have to be added in order to produce a rotating basket for certain circuit diagrams, and if U-shaped copper rods are not inserted into adjacent layers of a level who should, but should be placed in such a way that they skip one or more layers, i.e. jump from one level to another.

Based on this, the object of the present invention is to provide a device that can insert and screw in both special variants of the copper rods, that is to say also copper rods that skip layers when plugged in, in one operation.

The object is achieved by a positioning device for circumferentially positioning a plurality of copper rods around a central axis M, which describes an axial direction A, wherein the copper rods are essentially U-shaped with a first leg section and a second leg section, comprising a base plate and a the base plate rotatable about the central axis and transmission elements, which connect the base plate and the link plate with each other in such a way that they are each inserted pivotably into the base plate about pivot axes parallel to the central axis and engage in the link plate in radial guide links to when the link plate rotates to move radially in the guide linkages and to pivot about the respective pivot axis relative to the base plate, wherein the transmission elements have receiving spaces aligned along the respective pivot axis for receiving one of the leg sections of the copper rods.

The positioning device according to the invention is able, for example, to insert and screw copper rods in three levels, i.e. on six different radii, in one work step. For this purpose, the free ends of three copper rods are positioned or plugged into one transmission element each, so that the swaying movement of the transmission elements when the link plate rotates is transmitted to the inserted leg sections of the copper rods and these twist in. Screwing in here means that the free ends of the copper rods that are not inserted pivot from a radially outer position or a larger circumference to the radially inner position of the free ends of the copper rods inserted in the transmission element. That applies at least to U-shaped copper rods. I-shaped copper rods naturally have only one free end and must therefore always be inserted radially inward in a transmission element. However, the positioning device according to the invention is advantageous for the I-shaped copper rods because these copper rods always protrude beyond the U-shaped rods in the axial direction, so that the I-shaped copper rods have to be inserted before the U-shaped rods are screwed in , because the slots of the I-shaped rods are covered after screwing in in the axial direction.

An advantageous embodiment of the invention provides that the transmission elements are each inserted into bores arranged in a circle around the central axis M in the base plate. The position of these bores ultimately corresponds to the position of the stator and / or rotor element into which the completely screwed-in basket made of copper rods, referred to below as a wire basket, is inserted.

An advantageous embodiment of the invention provides that the transmission elements engage circumferentially alternately from the opposite axial direction in the link plate. This solves the generally existing space problems due to the tight placement of the copper rods in the circumferential direction in the screwed-in state.

An advantageous embodiment of the invention provides that the transmission elements have a cylindrical section arranged in the respective pivot axis and a pivot arm cantilevering therefrom. The cylindrical sections structurally form the base body by the transmission elements and it can furthermore be provided that the pivot arms are connected to the respective cylindrical section in one piece or, alternatively, detachably from one another.

An advantageous embodiment of the invention provides that the receiving spaces are formed in the cylindri's section of the transmission elements. This ensures a sufficiently stable Ler and more secure hold of the inserted free ends of the copper rods in alignment with the pivot axis of the transmission elements guaranteed.

An advantageous embodiment of the invention provides that the cylindrical section carries a retaining pin on one axial side. Via these retaining pins, the transmission elements can be safely inserted into the bores in the base plate, which are arranged in a circle around the central axis M.

An advantageous embodiment of the invention provides that the swivel arm of the transmission elements, according to their mutual arrangement with respect to the link plate, carries a further retaining pin at the end, which is in the same direction as the first retaining pin or is directed against the first hal test pin.

The invention is explained below with further features, details and advantages on the basis of the accompanying figures. The figures illustrate only exemplary embodiments of the invention. Show in it

FIG. 1 shows a positioning device according to the invention in one possible configuration;

Figures 2a), 2b) two variants of transmission elements of the positioning device according to Figure 1;

FIG. 3 shows a detail of a transmission element with inserted copper rods and

FIGS. 4a) to 5b) show a sequence of screwing in copper rods by means of the positioning device according to FIG. 1.

Figure 1 shows a positioning device 10 according to the invention in one possible Ausgestal device. The positioning device 10 is initially shown without inserted copper rods. The positioning device 10 comprises a base plate 12, which can also be designed like a frame or a housing. On the base plate 12 a rotatable about a central axis M link plate 14 is held. For this purpose, for example, vertical guide rollers 30 can be arranged circumferentially at a respective angle of 120 ° on the base plate 12, so that the link plate 14 is guided within these guide rollers 30 during rotation. Furthermore, three supports 32, which are also circumferentially and evenly offset with respect to the guide rollers 30 on the base plate, can be provided which hold the link plate 14 relative to the base plate 12. As a rotary drive, which is not shown here, a pneumatically or electrically driven actuating actuator can be provided, which engages largely tangentially on an outer circumference of the cooler disk 14. The link plate 14 forms a plurality of guide links 18 which are arranged next to one another in the circumferential direction and run ra dial relative to the central axis M. It can also be provided that the direction of the guide link 18 is at a certain angle of attack in relation to the radial direction. The guide links 18 can, as shown here, be designed as openings in the link plate 18. Alternatively, however, the guide links can also be designed as grooves.

Furthermore, the positioning device 10 comprises circumferentially arranged transmission elements 16, which connect the base plate 12 and the link plate 14 to one another in a form-fitting manner, so that when the link plate 14 rotates, swivel kinematics can be impressed on the transmission elements 16. The transmission elements 16 engage circumferentially and alternately from the opposite axial direction into the link plate 14. The design of the transmission elements 16, in particular their two variants that are used, which are explained below with reference to FIG. The transmission elements 16 are each inserted into bores 22 arranged in a circle around the central axis M in the base plate 12. The transmission elements 16 can be inserted into the bores 22 about a pivot axis S ver wasted.

FIGS. 2a) and 2b) each show a perspective view of the transmission element 16 in the two variants provided. FIG. 2a) shows the variant of the transmission element 16 for insertion from above into the base plate 12 and the link plate 14. FIG. 2b) shows the variant of the transmission element 16 for insertion from above into the base plate 12 and from below into the link plate 14. The basic structure of the two variants is the same. The transmission element 16 has a cylindrical section 24 and a pivot arm 26 protruding therefrom. In the assembled state, the cylindrical section 24 lies in the pivot axis S, about which the transmission element 16 can pivot with respect to the base plate 12. The pivot arm 26 projects from the cylindrical section 24 at a right angle, which in the variant of FIG. 2a) predominantly engages in the middle and in the variant of FIG. 2b) predominantly engages the cylindrical section 24 at the bottom. From the cylindrical sections 24 of both variants have at the axially lower end a first retaining pin 28 through which the respective transmission element 16 is pivotably held in the bore 22 of the base plate 12 th. A second retaining pin 34 is arranged at the end of the pivot arm 26, whereby in the first variant of FIG. 2a) the retaining pin 34 is aligned with the first retaining pin 28 and in the second variant of FIG. 2b) the retaining pin 34 is opposite to the first retaining pin 28. In addition, it can be seen in Figures 2a) and 2b) that the cylindrical section 24 of both variants of the transmission element 16 forms an upwardly open receiving space 20 for receiving one of the free ends of a copper rod 2, as will be explained in more detail with reference to further figures becomes.

FIG. 3 shows one of the two variants of the transmission element 16, in the receiving space 20 of which the respective leg sections 4 of three copper rods 2 are inserted. The width or the shape of each receiving space 20 of a transmission element 16 is designed in such a way that three leg sections 2 can be inserted with little play and then inserted in a form-fitting manner in the receiving space 20 such that the cylindrical section 24 can pivot about the pivot axis S. leads to the entrainment of the leg sections 2, so that the leg sections 4 that are not inserted also pivot accordingly. However, it is also conceivable that a number of leg sections 4 other than three are inserted into the receiving space 20, so that a correspondingly changed geometry is then provided for the form-fitting mounting about the pivot axis S.

The sequence of Figures 4a) to 4b) shows the screwing of copper rods 2, which are initially inserted with their leg sections 4 and 6 in the radial direction in the positioning device 10, to a wire basket 8 in which the leg sections are essentially immediately adjacent Circumferences lie and the transverse sections, which connect the leg sections to one another, at least partially overlap one another. FIG. 3 a) shows how the radially inner leg sections 4 are inserted into the receiving spaces 20 of the transmission elements 16. In the present case, the respective leg sections 4 are received by three copper rods 2 in a receiving space 20.

The present arrangement of three leg sections 2, which are inserted in a receiving space, leads to all inserted and initially fanned out copper rods 2 that three copper rods 2 are arranged directly next to one another and the next three copper rods are arranged under a certain circumferential gap .

The twisting in of the copper rods 2 from the fanned out position, shown in Figure 3a), to the finished wire basket 8, shown in Figure 4b), is effected by rotating the link plate 14 about the central axis M. This rotation is via the second Holding pins 34 which each engage in the guide link 18 of the link plate 14 and are transmitted as a pivot to the cylindrical sections 24 of the transmission elements 16 about the respective pivot axis S via the respective pivot arm 26. List of reference symbols

2 copper rod

4 leg section

6 leg section

8 wire basket

10 Positioning device 12 Base plate

14 link plate

16 transmission element 18 guide link

20 recording room

22 bore

24 cylindrical section 26 swivel arm

28 retaining pin

30 Leadership

32 supports

34 retaining pin

M central axis

5 swivel axis

Claims

1. Positioning device (10) for circumferentially positioning a plurality of copper rods (30) around a central axis M which describes an axial direction A, the copper rods (30) being essentially U-shaped with a first leg section (32) and a second Leg section (34) are formed, comprising a base plate (12) and a link plate (14) rotatable on the base plate (12) about the central axis M and

Transmission elements (16) which connect the base plate (12) and the link plate (14) to one another in such a way that they are each inserted into the base plate (12) so that they can pivot about the central axis M par allelic pivot axes S and in the link plate (14) in radial directions Guide links (18) engage in order to move radially in the guide links (18) when the link plate (14) rotates and to pivot about the respective pivot axis S relative to the base plate (12), the transmission elements (16) along the respective pivot axis S. have aligned receiving spaces (20) for receiving one of the leg sections (32, 34) of the Kup fer rods (30).

2. Positioning device (10) according to claim 1, characterized in that the transmission elements (16) are each inserted into bores (22) arranged in a circle around the central axis M in the base plate (12).

3. Positioning device (10) according to claim 1 or 2, characterized in that the transmission elements (16) circumferentially engage alternately from opposite axial direction in the link plate (14).

4. Positioning device (10) according to one of claims 1 to 3, characterized in that the transmission elements (16) have a cylindrical portion (24) arranged in the respective pivot axis S and a pivot arm (26) protruding therefrom.

5. Positioning device (10) according to claim 4, characterized in that the receiving spaces (20) in the cylindrical portion (24) of the transmission elements (16) are formed out.

6. Positioning device (10) according to claim 4 or 5, characterized in that the zy-cylindrical section carries a retaining pin (28) on one axial side.

7. Positioning device (10) according to claim 6, characterized in that the swivel arm (16) of the transmission elements (16), according to their mutual arrangement with respect to the link plate (14), carries a further retaining pin (34) at the end, which supports the first retaining pin (28 ) is rectified or is directed opposite to the first retaining pin (28).