WO2021037300A1

WO2021037300A1 - Torque transmission component having an annular receiving groove for positioning a balancing mass, electric motor, and balancing method

Info

Publication number: WO2021037300A1
Application number: PCT/DE2020/100664
Authority: WO
Inventors: Michael Ferber; Oleg Schneider
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2019-08-26
Filing date: 2020-07-27
Publication date: 2021-03-04
Also published as: DE102019122853A1

Abstract

The invention relates to a torque transmission component (1) for a motor vehicle drive, having a support (3) and a balancing mass (7) for balancing an imbalance of the support (3), wherein the balancing mass (7) is formed as an annular segment and is attached in an annular receiving groove (9) formed by the support (3) and/or the component (8) fixed to the support, said groove being axially open. The invention further relates to an electric motor (2) with a torque transmission component (1) of this kind and to a method for balancing a torque transmission component (1).

Description

Torque transmission component with an annular receiving groove for

Positioning a leveling compound; Electric motor and balancing process

The invention relates to a torque transmission component, preferably designed as a rotor arrangement for an electric motor, with a carrier and a balancing mass to compensate for an imbalance in the carrier. The invention also relates to an electric motor with this rotor arrangement and a method for balancing the torque transmission component.

Generic components that are equipped with means to compensate for an imbalance are already well known from the prior art.

On the one hand, the prior art is known in which several balancing bores are made in a component of a rotor in order to eliminate an imbalance. This variant means that under certain circumstances a relatively high number of bores must be made, especially in the carrier. Due to the relatively high notch load, this causes a significant weakening of the strength of the carrier. In addition, the bores adversely affect the realizable cycle time of the electric motor. In addition, there is a disadvantage with drilling that chips are produced. This causes the magnets present to attract these chips. Removing the chips is a relatively complex process.

As an alternative to this, as implemented, for example, by DE 10 2018 128 741 A1, it is conceivable to attach separate elements to the corresponding carrier in order to counteract the imbalance. The corresponding elements can be attached in different ways. The elements are positioned in the usual way by 180 ° in relation to the unbalance. The separately attached elements have the disadvantage, however, due to their previously used fastening methods, especially when using adhesive or screwing, the disadvantage that they can possibly come loose during operation. The elements can also be attached by welding, which means that measures must be taken against possible weld spatter. Accordingly, a relatively complex process validation is necessary when applying the leveling compounds. In addition, up to now a relatively large amount of additional installation space has to be provided by the balancing weights.

It is therefore the object of the present invention to eliminate the disadvantages known from the prior art and, in particular, to provide a balanced torque transmission component that has a higher strength / rigidity and is implemented in a space-saving manner.

This is achieved according to the invention in that the balancing mass is shaped as a ring segment and is placed / fastened in an annular, axially open receiving groove formed by the carrier and / or a component fixed to the carrier.

As a result of this design and accommodation of the balancing mass, it is integrated into the torque transmission component in a space-saving manner. For example, there is no longer any need to drill holes, with a relatively large number of chips being produced. This eliminates the need to clean the component or it is significantly simplified.

Further advantageous designs are claimed with the subclaims and explained in more detail below.

The torque transmission component is particularly preferably implemented as a Rotoran arrangement for an electric motor.

It is particularly useful if a plurality of magnets are attached to a radial outer side of a hül seniform receiving area of the carrier. This results in the most precise possible balancing of the electric motor.

As an alternative to the design as a rotor arrangement, it is also advantageous if the torque transmission component is implemented as another component, particularly preferably as a transmission component, more preferably a planet carrier. By providing the receiving groove between the carrier and the component fixed to the carrier, the compensating mass is received in an area that takes up as little separate installation space as possible.

In this context, it is particularly advantageous if the receiving groove is formed by a first radial shoulder of the carrier and by a second radial shoulder of a shaft element firmly connected to the carrier. As a result, the contour required for the formation of the receiving groove is simply made available.

The shaft element is further preferably implemented directly as a shaft having a toothing. Preferably, the toothing is implemented as a helical toothing.

It is also advantageous for a space-saving arrangement if the first radial offset is arranged on a radial inside of a hub region of the carrier.

In this regard, it is also useful if the second radial shoulder is arranged on a ra-media outside of the shaft element (at least partially) pushed into the carrier. As a result, the receiving groove is used in a space-saving manner in the connecting area of the shaft element with the carrier.

Furthermore, it is advantageous if the receiving groove is only made in one component, preferably the carrier, or alternatively also the component fixed to the carrier. As a result, a flat recess (groove in the flat side / front side of the component) is also implemented in a simple manner.

For an attachment that is easy to assemble and enables a sufficiently large holding force, it is also advantageous if the compensating mass is fixed / set in the circumferential direction in a force-locking and / or form-locking manner in the receiving groove. In order to implement a positive connection that is as strong as possible, it is also advantageous if the compensating compound is pressed into the receiving groove. In addition, the balancing mass is easy to assemble.

In this context, it is also expedient if the balancing mass has a wave shape / is corrugated. The balancing compound is preferably corrugated in particular in the circumferential direction and / or corrugated in the axial direction, as a result of which the joining process of the compensating compound is further facilitated. The wave shape creates a necessary clamping force in a simple manner when the balancing mass is pressed in axially.

If, as an alternative or in addition to the non-positive connection / press connection, the compensating mass is fixed by caulking on the carrier and / or caulking on the component fixed to the carrier, the positive connection is also easy to produce. The caulking are arranged in such a way that the balancing mass is secured against twisting in the circumferential direction.

It is also advantageous if, for the axial fixation of the compensating mass / for the axial closure of the receiving groove, a roller bearing is received axially in the carrier adjacent to the receiving groove. In particular, a (first) bearing ring of this rolling bearing is used to axially secure / support the balancing mass in the Aufnah merille.

In addition, it is advantageous if several of the balancing masses are attached in the circumferential direction ver sets in the receiving groove.

To facilitate the pressing process, an appropriately shaped chamfer geometry on the leveling compound or on the edge area forming the receiving groove of the carrier and / or the component fixed to the carrier is helpful. The invention further relates to an electric motor for a motor vehicle drive, with a stator and a rotor arrangement according to the invention, which is received radially within the stator and rotatably relative to the stator, according to at least one of the embodiments described above.

In addition, the invention relates to a method for balancing a torque transmission component, wherein in a first step a) a torque transmission component is provided which has a carrier with an annular and axially open receiving groove prepared for receiving a compensating mass designed as a ring segment. Preferably, the torque transmission component is provided in step a) as a rotor assembly, which rotor assembly has a Trä ger, several magnets attached to an outside of a sleeve-shaped receiving area of the Trä gers and an annular and axially open receiving groove prepared for receiving a compensating mass formed as a ring segment . In a second step b) an imbalance of this torque transmission component / this rotor arrangement is detected / determined. In a third step c) the balancing mass, which is designed as a ring segment, is shaped / manufactured with regard to its circumferential length and / or density in accordance with the size of the unbalance. And in a fourth step d) the balancing mass is attached in a circumferential area of the receiving groove opposite the unbalance. This results in an assembly that is easy to implement.

In other words, according to the invention, an annular groove (receiving groove) for positioning a balancing segment (balancing mass) is made available. The annular groove (receiving groove) is realized by two paragraphs in separate construction parts in a fully assembled rotor. A ring segment (balancing mass) is used in this groove to correct an imbalance in the rotor. A length of the ring segment (balancing mass) is adapted to the imbalance. A tangential / circumferential displacement of the ring segment is lifted by caulking or a press connection (preferably by a wave shape of the ring segment). A bearing prevents the ring segment from shifting in the axial direction.

The invention will now be explained in more detail below with reference to figures. Show it:

Fig. 1 is a longitudinal sectional view of a schematically illustrated electric motor with a rotor assembly according to the invention designed according to a preferred embodiment,

Fig. 2 is a front view of a used to compensate for an imbalance in Fig. 1 th balancing mass, the circumferential extent of which is easy to know, and

3 shows a flow chart to illustrate a balancing method according to the invention for use on the rotor arrangement according to FIG. 1.

The figures are only of a schematic nature and are used exclusively for understanding the invention. The same elements are provided with the same reference numerals.

With Fig. 1, an electric motor 2 is shown schematically. The electric motor 2 is equipped with a torque transmission component 1 according to the invention, as described in more detail below. In this embodiment, according to a preferred exemplary embodiment, the torque transmission component 1 is implemented as a rotor arrangement 1, which is why it is referred to below as a rotor arrangement 1. In further versions, other components, such as transmission components, can also be designed as this torque transmission component 1.

The electric motor 2 shown is used in its operation in a typical manner in a drive train to a motor vehicle. The electric motor 2 is used as a drive motor to the motor vehicle.

The directions used below axially, radially and in the circumferential direction relate to a central axis of rotation 26 of the rotor assembly 1, about which axis of rotation 26 the rotor assembly 1 can be rotated. One axial direction / axially loading consequently indicates a direction along / parallel to the axis of rotation 26; a radial direction / radial means a direction perpendicular to the axis of rotation 26 and a circumferential direction means a tangential direction along a circular line concentrically around the axis of rotation 26.

With FIG. 1, the electric motor 2 is only shown schematically with regard to its stator 16. The stator 16 is fixedly received in a housing of the electric motor 2 which is not further provided for the sake of clarity. Radially within the ringför-shaped stator 16, the rotor assembly 1 is rotatable about the axis of rotation 26 aufgenom men.

The rotor assembly 1 has a carrier 3 which, with its sleeve-shaped receiving area 5, receives a plurality of magnets 6 distributed in the circumferential direction. The magnets 6 are either permanent magnets or electromagnets, i.e. H. designed as magnetizable elements. The magnets 6 are fastened on a radial outer side 4 of the receiving area 5. The magnets 6 are preferably glued directly to the carrier 3 or to an envelope area connected to the carrier 3.

The receiving area 5 merges on one axial side into a disk area 23 extending inwardly away from the receiving area 5 in the radial direction. The disk area 23 in turn merges into a hub area 14 on its radial inside. The hub region 14 extends to an axial direction opposite to the receiving region 5 from the disk region 23.

A component 8 fixed to the carrier is attached to the carrier 3. This carrier-fixed Be component 8 is implemented as a toothed (namely externally toothed) shaft element 12. The shaft element 12 has an insertion area 24 which is inserted directly into the hub area 14. A toothed area 25 protruding axially out of the hub area 14 directly adjoins the insertion area 24 axially. The toothing area 25 is characterized by external toothing, here a helical gearing, implemented. The carrier-fixed component 8 is used during operation to transmit a torque to other components of the drive train. The shaft element 12 is taken with its insertion region 24, which is supported radially from the inside on a radial inner side 13 of the hub region 14, fastened to the hub region 14, for example via a welded connection or a press connection.

According to the invention, an axially open and circumferentially continuous and completely encircling / annular receiving groove 9 for a balancing mass 7 (/ balancing segment) is now formed in common sam in the fixed component 8 and the carrier 3. The receiving groove 9 forms an annular groove. The receiving groove 9 is open on a side facing away from the toothed area 25 axially. The balancing mass 7 is shown in Fig. 1 in an upper (first) circumferential region 21 of the longitudinal section.

A first part of the receiving groove 9, namely a radially outer part of the receiving groove 9, is implemented directly by a first radial shoulder 10 on the inside 13 of the hub region 14. A second part of the receiving groove 9, namely a radially inner part of the receiving groove 9, is formed directly by a second shoulder 11 on a radial outer side 15 of the component 8 fixed to the carrier. The two radia len paragraphs 10, 11 are formed essentially in opposite directions and are located in the axial direction at the same height. The receiving groove 9 is consequently radially outwards directly through the inside 13 of the hub area 14, radially inwards through the outside 15 of the component 8 fixed to the carrier and on an axial side by the axial side edges of the hub area 14 and the component 8 fixed to the carrier, which are axially at the same height and are arranged radially next to each other, implemented.

The balancing mass 7 can also be seen clearly in FIG. 2. The balancing mass 7 is implemented as a ring segment, ie in the shape of a segment of an arc. The balancing mass 7 is shown in FIG. 1 directly inserted and fixed in the receiving groove 9 in a corresponding ge desired area. For this purpose, in a preferred Ausfüh tion, as it is implemented in Fig. 1, a form-fitting fastening implemented by means of several caulking. For the sake of clarity, they are not shown further Caulking is preferably implemented on the component 8 fixed to the carrier and the hub area 14 in such a way that the compensating mass 7 is fixed in the receiving groove 9 in a position-securing manner in the circumferential direction. According to further explanations, it is also possible, please include only to form the component 8 fixed to the carrier or the carrier 3 on the hub region 14 with caulking in order to achieve this circumferential securing of the balancing mass 7.

As an alternative to the positive connection, a non-positive connection, in the form of a press connection, is provided between the compensating mass 7 and the receiving groove 9 in further embodiments according to the invention. The balancing compound 7 is pressed axially into the receiving groove 9 and rests preferably radially via a press connection on the inside 13 of the hub area 14 and on the outside 15 of the component 8 fixed to the carrier. In further embodiments according to the invention, the balancing mass 7 has a wave shape running in the circumferential direction. Radial inner and outer circumferential sides of the balancing mass 7 are consequently shaped like corrugated in the circumferential direction. Furthermore, it is also advantageous if the balancing mass 7 is implemented as corrugated in the axial direction and thus has two oppositely directed axial side surfaces which are corrugated in the same way in the circumferential direction.

The roller bearing 17 shown schematically in FIG. 1 is inserted axially next to the receiving groove 9 and the component 8 fixed to the carrier. The roller bearing 17 has a first bearing ring 18 (bearing outer ring) which rests directly next to the receiving groove 9 in the axial direction and consequently serves as an axial securing element for the compensating mass 7. The balancing mass 7 is thus also secured against axial slipping out by the roller bearing 17. The roller bearing 17, here implemented as a ball bearing, typically furthermore has a second bearing ring 19 (Lagerin nenring) which is rotatably mounted relative to the first bearing ring 18 over a plurality of rolling elements 20.

In connection with FIG. 3, an inventive balancing method of a rotor assembly 1 according to FIG. 1 is illustrated. Here, in a first step a), the rotor arrangement 1 is made available to the extent that the component 8 is connected to the carrier 3 and the magnets 6 are already attached to the outside 4 of the receiving area 5. The rotor arrangement 1 is therefore already finished in this step a) to such an extent that only the balancing mass 7 and then the roller bearing 17 need to be attached to the rotor arrangement 1.

In a subsequent step b), an imbalance in this rotor arrangement 1 is detected / measured in a corresponding device. As a result, a second circumferential area 22, which is shown in FIG. 1, is the lower circumferential area 22 of the rotor arrangement 1, which is unbalanced.

In a subsequent step c), the balancing mass 7 is adapted to the size of the imbalance. For this purpose, the balancing mass 7 is shaped, in particular with regard to its length measured in the circumferential direction, in such a way that it applies a force which is directed against the imbalance / compensates for the imbalance in the inserted state. In further embodiments, in addition or as an alternative to the length, a density of the balancing compound 7 is set accordingly in this step c).

On the first circumferential area 21 opposite the second circumferential area 22 approximately by 180 °, the balancing compound 7 is then typically fixed in a step d) and inserted into the receiving groove 9 by means of the non-positive and / or positive-locking connection.

In an optional further step e), the roller bearing 17 with its bearing ring 21 is finally pressed into the carrier 3, so that the bearing ring 21 comes into contact immediately axially next to the receiving groove 9 and forms an axial securing of the compensating mass 7. In the case of the design with the occasional / corrugated balancing mass, this simultaneously creates a clamping (preferably at several points in the existing contact surfaces of the carrier 3 with the component 8 fixed to the carrier).

In other words, according to the invention, by providing two shoulders 10, 11 in the individual parts in the finished rotor 1, an annular groove 9 is created In groove 9, a corresponding ring segment 7 is inserted through which the imbalance is eliminated. The ring segment 7 (balancing mass) is to be adapted to the appropriate length according to the imbalance. The ring segment 7 is secured against displacement (tangential) by a subsequent caulking (plasti cal reshaping). An alternative variant is a wave-shaped ring segment 7 which is pressed in. A backup in the radial direction is not necessary because the two individual parts absorb these forces. In the axial direction, the subsequent pressing-in of the bearing 20 ensures that the ring segment 7 does not migrate. A preferred application is in a rotor assembly assembly on a chainless drive.

In a first variant, a shoulder 11 is provided in the toothed component 8.

In the rotor arm 3, an equally deep shoulder 10, as in the toothed component 8, is provided. By joining the two components 3, 8, a circumferential annular groove 9 is created. In this state, the imbalance is now measured in the assembly. Then the ring segment 7 is inserted into the ring groove 9 (length of the ring segment 7 depends on the imbalance to be eliminated; furthermore, the material can also be adapted with the corresponding density). By caulking the ring segment 7 is secured against tan gential displacement. Axial securing takes place by pressing the bearing 20 into a reference diameter (of the hub area 14).

In a second variant, a paragraph 11 is initially provided in the toothed construction part 8, analogous to the first variant. In the rotor arm 3 an equally deep paragraph 10, as in the toothed component 8, is provided. By joining the two components 3, 8, a circumferential annular groove 9 is created. In this state, the imbalance is now measured in the assembly. Then the ring segment 7 is pressed into the ring groove 9 (length of the ring segment 7 depends on the imbalance to be eliminated; furthermore, the material can also be adapted with the corresponding density). Here, the ring segment 7 has a wave shape in the circumference and in the thickness.

The wave shape creates a clamping force when it is pressed in. Axial hedging takes place by pressing the bearing 20 into the reference diameter (of the hub area 14). The wave shape also creates additional clamping here. In general, the following applies: The wave shape in the second variant enables clamping at several points in the contact surfaces. Bezuqszeichenliste Torque transmission component / rotor arrangement electric motor carrier outside of the receiving area receiving area magnet balancing mass carrier-fixed component receiving groove first paragraph second paragraph shaft element inside of the hub area hub area outside of the component fixed to the carrier stator roller bearing first bearing ring second bearing ring rolling element first circumferential area second circumferential area disk area insertion area toothing area axis of rotation

Claims

1. Torque transmission component (1) for a motor vehicle drive, with egg nem carrier (3) and a balancing mass (7) to compensate for an imbalance of the carrier (3), characterized in that the balancing mass (7) is shaped as a ring segment and in a annular, formed by the carrier (3) and / or a support-fixed component (8) and axially open receiving groove (9) is attached.

2. Torque transmission component (1) according to claim 1, characterized in that the torque transmission component (1) is implemented as a Rotoran arrangement (1) for an electric motor (2) or as a transmission component.

3. Torque transmission component (1) according to claim 2, characterized in that a plurality of magnets (6) are mounted on a radial outer side (4) of a sleeve-shaped receiving area (5) of the carrier (3).

4. torque transmission component (1) according to any one of claims 1 to 3, characterized in that the receiving groove (9) by a first radia len paragraph (10) of the carrier (3) and by a second radial paragraph (11) one with the carrier (3) firmly connected shaft element (12) is formed.

5. torque transmission component (1) according to claim 4, characterized in that the first radial shoulder (10) on a radial inner side (13) egg Nes hub region (14) of the carrier (3) is arranged.

6. torque transmission component (1) according to claim 4 or 5, characterized in that the second radial shoulder (11) is arranged on a radial outer side (15) of the shaft element (12) pushed into the carrier (3).

7. Torque transmission component (1) according to one of claims 1 to 6, characterized in that the balancing mass (7) is fixed positively and / or positively in the receiving groove (9) in the circumferential direction.

8. Torque transmission component (1) according to one of claims 1 to 7, characterized in that the balancing mass (7) is pressed into the receiving groove (9) and / or by caulking on the carrier (3) and / o the caulking the carrier-fixed component (8) is fixed.

9. Electric motor (2) for a motor vehicle drive, with a stator (16) and one radially inside the stator (16), relative to the stator (16) rotatably recorded rotor assembly (1) according to one of claims 2 to 8.

10. A method for balancing a torque transmission component (1), where in a first step a) a torque transmission component (1) which has a carrier (3) with a ring-shaped and axially open receiving groove prepared for receiving a compensating mass (7) designed as a ring segment (9) is provided; in a second step b) an imbalance of this torque transmission component (1) is detected; in a third step c) the compensating mass (7) designed as a ring segment is made with regard to its length and / or density on the circumferential side corresponding to the size of the unbalance; and in a fourth step d) the balancing mass (7) is fastened in a circumferential region (21) of the receiving groove (9) opposite the unbalance.