WO2023066515A1

WO2023066515A1 - Electric motor with a rotor shaft and a housing which has a stator housing part

Info

Publication number: WO2023066515A1
Application number: PCT/EP2022/025460
Authority: WO
Inventors: Li Jinchang
Original assignee: Sew-Eurodrive Gmbh & Co. Kg
Priority date: 2021-10-22
Filing date: 2022-10-05
Publication date: 2023-04-27
Also published as: DE102022003691A1

Abstract

The invention relates to an electric motor with a rotor shaft and a housing which has a stator housing part. The rotor shaft is rotatably supported via a first bearing and a second bearing, wherein the first bearing is received in the housing, and the second bearing is received in the housing. The rotor shaft is inserted and/or protrudes through a disc, and the disc is releasably connected to the housing and to the rotor shaft.

Description

Electric motor with a rotor shaft and a housing, which has a stator housing part

Description:

The invention relates to an electric motor with a rotor shaft and a housing which has a stator housing part.

It is well known that when an electric motor moves, the rotor shaft puts a load on the bearing.

From DE 10 2008 028604 A1, an electric motor with an electromagnetically actuable brake is known as the closest prior art.

DE 11 67 967 A discloses a device for protecting roller bearings in electrical machines against transport damage by means of a bracket.

DE L 221 87 AZ discloses a transport lock for rolling bearings in electrical machines.

A transport lock for an electrical machine is known from DE 10 2004 058 349 B3.

An electric motor is known from DE 10 2010 045 447 A1.

A corrosion-resistant bearing is known from DE 10 2006 046 238 A1.

A method for producing an electric motor is known from DE 10 2010 024 302 A1.

The invention is therefore based on the object of further developing an electric motor, with the aim of increasing safety. According to the invention, the object is achieved with the electric motor according to the features specified in claim 1 or 2.

Important features of the invention have an electric motor with a rotor shaft and a housing, which has a stator housing part, the rotor shaft being rotatably mounted via a first bearing and via a second bearing, the first bearing being accommodated in the housing and the second bearing being accommodated in the housing , wherein the rotor shaft is inserted through a disc and / or protrudes, wherein the disc is detachably connected to the housing and to the rotor shaft, in particular wherein the rotor shaft is non-rotatably connected to the housing.

The advantage here is that security is increased. This is because the attachment of the rotor shaft prevents the bearings from being overloaded, for example as a result of excessive lateral forces and/or axial forces. According to the invention, lateral forces and axial forces can be transmitted via the disk to the housing, in particular to the cover of the housing, and from there to the bearing flange, from where the forces are transmitted to the stator housing.

In an advantageous embodiment, the first bearing is designed as a loose bearing and the second bearing is designed as a fixed bearing. The advantage here is that the disk can be arranged closer to the floating bearing than to the fixed bearing, and forces are thus kept away from the floating bearing and diverted via the disk.

In an advantageous embodiment, the disc is made of plastic, in particular as a plastic injection molded part. The advantage here is that a shock-absorbing property, in particular a vibration-absorbing property, of the plastic improves the protection of the bearing. In an advantageous embodiment, the housing has a first bearing flange in which the first bearing is accommodated and which is connected to the stator housing part, in particular by means of screws, in particular the housing has a second bearing flange in which the second bearing is accommodated and which is connected to the stator housing part, in particular by means of screws. The advantage here is that the respective bearing is accommodated in the housing.

In an advantageous embodiment, a cover, in particular a cover on the side of the first bearing flange facing away axially from the second bearing, is connected to the bearing flange, in particular by means of screws. The advantage here is that the first bearing is protected from the environment by the cover and a shaft sealing ring can be accommodated in the cover, so that the first bearing can be fully protected from dirt and dust.

In an advantageous embodiment, a shaft sealing ring is accommodated in the cover, which seals against the rotor shaft. The advantage here is that the first bearing is provided with full protection.

In an advantageous embodiment, a screw guided, in particular screwed, through a radial bore of the disk presses on a feather key accommodated in a feather key groove of the rotor shaft. The advantage here is that the rotor shaft is protected from damage and the feather key provides a tangentially aligned surface area of the screw for pressing.

In an advantageous embodiment, at least one additional screw passing through an axial borehole in the disk is screwed into a threaded borehole, in particular an axial borehole, in the cover. The advantage here is that the screw pulls the disk towards the cover with its screw head, so that the disk can be adjusted against a shaft step, in particular a shaft collar. In this way the rotor shaft is then pushed towards the second bearing.

In an advantageous embodiment, the screw head of the further screw is on the disk, in particular on a side of the disk facing away from the cover, in particular a collar area of the disk. The advantage here is that the disc pushes the rotor shaft towards the second bearing, thus relieving the load on the first bearing.

In an advantageous embodiment, the disk is placed against a shaft collar, in particular a shaft step, of the rotor shaft. The advantage here is that the rotor shaft is pressed towards the second bearing, allowing lateral forces and other forces to be dissipated.

In an advantageous embodiment, the disc has a base body and a collar area, the base body being hollow-cylindrical and the collar area also being hollow-cylindrical, the collar area being aligned coaxially with the base body, the outer diameter of the collar area being larger than the outer diameter of the base body, the Run through the radial bore is performed by the base body, wherein the axial bore is performed continuously through the collar area. The advantage here is that simple production is made possible.

In an advantageous embodiment, one or more nuts, acting in particular as a lock nut, are screwed onto the further screw in such a way that a minimum axial distance between the cover and the disk is ensured. The advantage here is that a long operating time is carried out with undisturbed components.

In an advantageous embodiment, the cover is centered on the bearing flange by means of a centering collar formed on the cover. The advantage here is that the cover can be aligned precisely and without play on the bearing flange.

In an advantageous embodiment, on the side of the second bearing facing away from the first bearing, in particular axially, there is a sensor for detecting the angular position of the arranged rotor shaft. The advantage here is that due to the proximity to the floating bearing, the measuring accuracy is very high and the sensor is only slightly loaded with axial displacements. In an advantageous embodiment, the area covered in the axial direction by a fan hood connected to the housing contains the area covered by the sensor in the axial direction, in particular the fan hood enclosing the sensor. The advantage here is that the sensor is protected and therefore safely arranged.

In an advantageous embodiment, the bearing flange, the cover and the rotor shaft are each made of metal, in particular steel or cast steel. The advantage here is that the structure-borne noise vibrations or vibrations conducted through the metallic and therefore stiff parts can be damped by means of the disk made of plastic.

Further advantages result from the dependent claims. The invention is not limited to the combination of features of the claims. For the person skilled in the art, there are further meaningful combinations of claims and/or individual claim features and/or features of the description and/or the figures, in particular from the task and/or the task arising from comparison with the prior art.

The invention will now be explained in more detail using schematic illustrations:

FIG. 1 shows a longitudinal section through a region of an electric motor according to the invention with a disk 8 functioning as a transport lock.

FIG. 2 shows an oblique view of the electric motor.

In the figure 3, the disc 8 is shown in an oblique view.

As shown in the figures, the electric motor has a rotatably mounted rotor shaft 7 .

The stator housing of the electric motor accommodates the stator laminated core together with the stator winding and is connected to a bearing flange 1, in which a first bearing 2 is accommodated, which is designed as a movable bearing, ie in particular is arranged with play in the axial direction.

That continuous recess in the bearing flange 1, in which the first bearing 2 is accommodated, is covered from the outside by a cover 10, which is connected to the bearing flange 1 and accommodates a shaft sealing ring 9, which seals off the rotor shaft 7, in particular by its Sealing lip runs on a finely machined sealing surface of the rotor shaft 7.

A further bearing of the rotor shaft 7 is accommodated in a further flange part, in particular which is arranged on the B-side. In this case, the further bearing is designed as a fixed bearing, so that an angle sensor can be arranged there, in particular because of the small amount of play. A fan, which is surrounded by a fan cover 20, is arranged axially next to the angle sensor.

The inner ring of the bearing 2, ie the loose bearing, is pushed onto the rotor shaft 7 and the outer ring of the bearing 2 is accommodated in a cylindrical bore of the bearing flange 1. The inside diameter of the hole is therefore larger than the outside diameter of the rotor shaft 7. The cover 10 is therefore slipped onto the shaft so that there is only a narrow annular gap between the rotor shaft 7 and the cover 10. The cover 10 has a centering collar with which it is centered on the edge of the bore on the bearing flange 1 . The cover 10 thus covers the hole.

The shaft sealing ring is accommodated in the cover 10, the sealing lip of which runs on a sealing surface of the rotor shaft 7 and thus seals off the shaft.

In the axial end area of the rotor shaft 7 protruding through the cover 10 there is an axially extending feather keyway, into which a feather key 6 is inserted, which protrudes radially from the rotor shaft 7 .

Preferably, the feather key 6 has a surface area aligned tangentially with respect to the axis of rotation of the rotor shaft 7 .

The rotor shaft 7 is made of steel.

A disk 8 is slipped onto the rotor shaft 7 as a transport safeguard. For this purpose, the disc 8 has a hole formed in the middle of it.

The disc 8 is preferably made of plastic.

A screw 4 is passed through a radial bore 30 running through the disc 8 and presses on the surface area, ie in particular on the feather key.

Another screw 3 is passed through an axial bore 31 of the disc 8 and screwed into an axially directed bore of the cover 10. An axial delimitation and fixing of the disk 8 can be achieved by means of a first nut 5, in particular a lock nut. An axial limitation and fixation of the cover 10 can be achieved by means of a second nut, which is also screwed onto the screw 3 .

The nuts preferably function as lock nuts.

The screw head of the screw presses the disc 8 on its side facing away from the cover 10 towards the cover 10, whereby the disc 8 against a wave stage of the Rotor shaft 7 is employed and thus presses the rotor shaft against the fixed bearing, which is arranged on the side of bearing 2 axially remote from cover 10 . The rotor shaft 7 is thus fixed in the axial direction towards the fixed bearing, in particular fixed without play.

The shaft is also secured in the radial direction by the screw 4, which is passed through the radial bore 30 of the disc 8 and presses on the feather key of the rotor shaft 7 in the radial direction. This is because the disc 8 is connected to the cover 10 by the further screw 3, which is guided through the axial bore of the disc 8, and is connected by means of screws to the bearing flange 1, which is connected to the stator housing. Thus, the rotor shaft 7 is also secured in the radial direction.

The disk 8 has a hollow-cylindrical base body, with an axial groove being provided on its inner circumference, into which the feather key 6 protrudes.

The radial bore 30 runs through the base body and may also be designed as a threaded bore. Alternatively or additionally, a nut is arranged in a countersink arranged on the outer circumference of the base body and/or is materially connected, so that the screw 4 is supported on the screw thread of the nut and/or the threaded bore and presses on the key 6 in the process.

A radially protruding collar area is placed on an axial end area of the base body, which in particular is also designed as a hollow cylinder. The collar area is designed in one piece with the base body, that is to say in one piece, in particular as a plastic injection molding.

The outside diameter of the collar area is larger than the outside diameter of the base body. The axial bores 31 are continuous through the collar area, in particular the axial bores 31 being spaced apart from one another in the circumferential direction, in particular spaced evenly.

In further exemplary embodiments according to the invention, the screw 4 is not pressed onto the feather key 6 but directly onto the rotor shaft 7 . reference list

1 bearing flange 2 bearings, especially floating bearings

3 screw

4 screw

5 mother

6 key 7 rotor shaft

8 disc

9 shaft seal

10 lids

20 Fan Cover 30 Radial Bore

31 axial bore

Claims

Patent Claims:

1. Electric motor with a rotor shaft and a housing, which has a stator housing part, the rotor shaft being rotatably mounted via a first bearing and via a second bearing, the first bearing being accommodated in the housing and the second bearing being accommodated in the housing, characterized in that that the rotor shaft is inserted through a disc and / or protrudes, the disc being detachably connected to the housing and to the rotor shaft, in particular the rotor shaft being non-rotatably connected to the housing.

2. Electric motor with a rotor shaft and a housing, which has a stator housing part, the rotor shaft being rotatably mounted via a first bearing and via a second bearing, the first bearing being accommodated in the housing and the second bearing being accommodated in the housing, characterized in that that the rotor shaft is pushed through and/or protrudes through a disc, the disc being detachably connected to the housing and to the rotor shaft, the rotor shaft being non-rotatably connected to the housing, a guided, in particular screwed, through a radial bore of the disc, Screw presses on a key held in a keyway of the rotor shaft, the disc having a hollow-cylindrical base body, with an axial groove being provided on its inner circumference, into which the key protrudes.

3. Electric motor according to claim 1, characterized in that the first bearing is designed as a floating bearing and the second bearing is designed as a fixed bearing, and/or that the disc is made of plastic, in particular as a plastic injection molded part.

4. Electric motor according to one of the preceding claims, characterized in that the housing has a first bearing flange, in which the first bearing is accommodated and which is connected to the stator housing part, in particular is connected by means of screws, in particular the housing has a second bearing flange, in which the second bearing is accommodated and which is connected to the stator housing part, in particular is connected by means of screws.

5. Electric motor according to one of the preceding claims, characterized in that a cover, in particular a cover on the axially remote from the second bearing side of the first bearing flange, is connected to the bearing flange, in particular by means of screws.

6. Electric motor according to one of the preceding claims, characterized in that a shaft sealing ring is accommodated in the cover, which seals towards the rotor shaft.

7. Electric motor according to one of the preceding claims, characterized in that a guided through a radial bore of the disc, in particular screwed, screw presses on a recorded in a keyway of the rotor shaft feather key.

8. Electric motor according to one of the preceding claims, characterized in that at least one further screw passing through an axial bore of the disc is screwed into a threaded bore, in particular an axial bore, of the cover.

9. Electric motor according to one of the preceding claims, characterized in that the screw head of the further screw presses on the disk, in particular on a side of the disk facing away from the cover, in particular a collar region of the disk.

10. Electric motor according to one of the preceding claims, characterized in that the disc is employed against a shaft collar, in particular shaft step, of the rotor shaft.

11. Electric motor according to one of the preceding claims, characterized in that the disc has a base body and a collar area, the base body being hollow-cylindrical and the collar area also being hollow-cylindrical, the collar area being aligned coaxially with the base body, the outer diameter of the collar area being larger as the outer diameter of the body, the radial bore being formed through the body, the axial bore being formed through the collar portion.

12. Electric motor according to one of the preceding claims, characterized in that one or more nuts acting in particular as a lock nut are screwed onto the further screw in such a way that a minimum axial distance between the cover and the disc is secured.

13. Electric motor according to one of the preceding claims, characterized in that the cover is centered on the bearing flange by means of a centering collar formed on the cover, and/or that on the side of the second bearing facing away from the first bearing, in particular axially, there is a sensor for detecting the angular position the rotor shaft is arranged.

14. Electric motor according to one of the preceding claims, characterized in that the area covered by a fan hood connected to the housing in the axial direction contains the area covered by the sensor in the axial direction, in particular the fan hood enclosing the sensor.

15. Electric motor according to one of the preceding claims, characterized in that the bearing flange, the cover and the rotor shaft are each made of metal, in particular steel or cast steel.