Electric motor

Abstract

The invention relates to an electric motor, wherein the electric motor has a stator housing which is connected on the one hand to a bearing shield of the electric motor, said bearing shield accommodating a bearing of the rotor shaft of the electric motor, and is connected on the other hand to a bearing flange that accommodates a further bearing of the rotor shaft, wherein a magnetic body of an electromagnetically actuatable brake of the electric motor is connected to the bearing shield for conjoint rotation therewith, wherein a hood encloses the magnetic body so as to form a housing and is pressed against the bearing shield via an interposed seal.

Description

[0001] electric motor

[0002] Description:

[0003] The invention relates to an electric motor.

[0004] It is generally known that an electric motor can be designed with an integrated brake and thus increased safety can be achieved through the ability to brake the electric motor.

[0005] The invention is therefore based on the object of developing an increased safety of the electric motor.

[0006] According to the invention, the object is achieved in the electric motor according to the features specified in claim 1.

[0007] Important features of the invention in the electric motor are that the electric motor has a stator housing which is connected on the one hand to a bearing plate of the electric motor which receives a bearing of the rotor shaft of the electric motor and on the other hand to a bearing flange which receives a further bearing of the rotor shaft, wherein a magnetic body of an electromagnetically actuated brake of the electric motor is connected in a rotationally fixed manner to the bearing plate, in particular wherein the magnetic body is arranged on the side of the bearing plate axially facing away from the stator housing, wherein a hood surrounds the magnetic body in a housing-forming, in particular watertight and / or airtight, and is pressed onto the bearing plate via an intermediate seal, in particular a flat seal, in particular by screw heads of screws, in particular whose threaded area is screwed into threaded holes in the bearing plate.The advantage here is that the cover surrounds the brake like a housing and is tightly connected to the bearing plate. This allows the brake to be integrated into the electric motor with a high degree of protection.

[0008] In an advantageous embodiment, at least one screw, in particular a long screw, screw or threaded rod, projects through the bearing flange, the stator housing and the bearing shield, and the bearing shield is pressed towards the stator housing by means of a screw head of the screw or a nut screwed onto the screw, and the bearing flange is pressed towards the stator housing by means of a screw head of the screw or a nut screwed onto the screw. The advantage here is that the screw holds the electric motor together and their first axial end projects into the interior space surrounded by the cover. Sealing is ensured by providing sealing rings on the screw heads of the screw or on the nuts.

[0009] In an advantageous embodiment, a sealing ring is placed on the screw, which rests against the bearing plate, with the screw head or nut pressing against the bearing plate via the sealing ring. This ensures a high degree of protection for the brake.

[0010] In an advantageous embodiment, the hood has adjacent cylinder jacket sections in the circumferential direction. This provides the advantage of increased rigidity. Nevertheless, the hood can be designed with a low vibration tendency and / or vibration capability. Therefore, vibrations of the hood are dampened and resonance vibrations are avoided.

[0011] In an advantageous embodiment, the areas covered by the respective cylinder jacket sections in the circumferential direction are each of equal size. This is advantageous because it enables simple manufacturing.

[0012] In an advantageous embodiment, the cylinder axis of the respective cylinder jacket section is aligned parallel to the rotational axis of the electric motor's rotor shaft and is spaced apart from the rotational axis of the electric motor's rotor shaft. This advantageously reduces the curvature of the cylinder jacket sections compared to the design of the radial outer circumference of the hood as a continuous cylinder jacket.

[0013] In an advantageous embodiment, the radius of each cylinder jacket section is greater than half the largest outer diameter of the hood. This is advantageous because the curvatures of the cylinder jacket sections are flatter than if the outer circumference of the hood were designed as a continuous cylinder. This allows water to drain away in essentially all mounting directions, achieves high rigidity, and suppresses resonances.

[0014] In an advantageous embodiment, the radius of each cylinder jacket section is larger than the largest radial distance of the cover relative to the rotor shaft's rotational axis. This advantageously results in the cylinder jacket sections being flatter than when the outer circumference of the cover is designed as a continuous cylinder. This allows water to drain away in essentially all mounting directions, achieves high rigidity, and suppresses resonances.

[0015] In an advantageous design, the wall thickness of the hood is constant. This is advantageous because it allows for simple manufacturing.

[0016] In an advantageous embodiment, the wall thickness of the hood is independent of the circumferential direction. This is advantageous because it allows for simple manufacturing.

[0017] In an advantageous embodiment, the screw means protrude from the bearing plate into the interior area surrounded by the hood. This is advantageous in that the screw means connect the electric motor, and the axial end region of the screw means protrudes into the interior area surrounded by the hood.

[0018] In an advantageous embodiment, the threaded rods protrude axially through the magnetic body and protrude axially from the magnetic body on both sides, in particular, wherein a further magnetic body of a further brake can be attached to the threaded rods protruding from the magnetic body. The advantage here is that increased safety can be achieved by providing an additional brake. For this purpose, the rotor shaft must then protrude through at least the magnetic body of the brake arranged axially closer to the bearing plate.

[0019] In an advantageous embodiment, a ring-shaped externally toothed driver is placed on the rotor shaft and is connected to the rotor shaft in a rotationally fixed manner, in particular by means of

[0020] Keyed connection, wherein a ring-shaped brake pad carrier is placed on the driver and is in engagement with its internal toothing with the external toothing of the driver, so that the brake pad carrier is arranged in a rotationally fixed manner with the driver and axially displaceable relative to the driver, wherein an energizable coil is accommodated in an annular recess of the magnetic body, wherein an armature disk is arranged axially between the magnetic body and the brake pad carrier, wherein the armature disk is connected in a rotationally fixed manner to the magnetic body, wherein the armature disk is arranged in an axially movable manner, in particular by means of bolts projecting through recesses in the armature disk, in particular axially directed, being pressed into recesses in the magnetic body, wherein the armature disk is arranged on the side of the brake pad carrier axially facing away from the bearing plate, wherein supported on the magnetic body,Spring elements spaced apart circumferentially press against the armature disk, particularly with a braking surface formed on the bearing plate. The advantage here is that in the event of a power failure, the brake engages automatically and is only released when the coil is energized.

[0021] In an advantageous embodiment, when the coil is energized, the armature disk is pulled toward the magnet body against the spring force generated by the spring elements. This increases safety, as release is only possible when energized.

[0022] In an advantageous embodiment, when the coil is de-energized, the armature disk is pressed onto the brake pad carrier by the spring elements, thus pressing the brake pad carrier onto the braking surface formed on the bearing plate or onto a friction plate attached to the bearing plate and having a braking surface. This increases safety because the brake is applied in the event of a power failure.

[0023] In an advantageous embodiment, the armature disc and the brake pad carrier are enclosed by the cover and / or are arranged in the interior area enclosed by the cover. The advantage here is that the brake is completely enclosed and protected by the cover.

[0024] In an advantageous embodiment, the hood is made as an injection-molded plastic part. This allows for simple and cost-effective production. An alternative design made of steel results in higher molding costs but also increased safety due to the more mechanically resistant material.

[0025] Further advantages emerge from the dependent claims. The invention is not limited to the combination of features in the claims. Further possible combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent to those skilled in the art, particularly from the problem and / or the problem posed by comparison with the prior art.

[0026] The invention will now be explained in more detail using schematic illustrations:

[0027] Figure 1 shows a longitudinal section through an electric motor according to the invention.

[0028] Figure 2 shows a section of the electric motor in an exploded view.

[0029] Figure 3 shows the electric motor in an oblique view.

[0030] As shown in the figures, the electric motor has a stator housing 5 which is connected on the one hand to a bearing flange 6 and on the other hand to a bearing shield 1.

[0031] The bearing plate 1 is spaced apart from the bearing flange 6 and accommodates a bearing for the rotatable support of the rotor shaft. The bearing flange 6 accommodates another bearing for the rotatable support of the rotor shaft.

[0032] Long screws connect the bearing shield 1 and the bearing flange 6 to the stator housing 5.

[0033] The respective long screw therefore protrudes through a recess in the bearing plate 1 and through a recess in the bearing flange 6. A screw head of this long screw presses onto the bearing plate 1 via a sealing ring 20 placed on the long screw, while a nut screwed onto a threaded area of ​​the long screw presses onto the bearing flange 6. Thus, both the bearing flange 6 and the bearing plate 1 are pressed onto the stator housing 5.

[0034] The sealing ring 20 ensures the safety and tightness of the connection between the long screw and the bearing flange 6.

[0035] The long screws hold the electric motor together.

[0036] The electric motor also has an electromagnetically actuated brake, which has a ferromagnetic magnetic body 2, which is rotationally fixedly connected to the bearing plate 1 by means of threaded rods 3 extending through the magnetic body 2. The threaded rods 3 protrude from the magnetic body 2, so that a second brake can be mounted axially next to the first brake, thus achieving increased operational reliability.

[0037] The magnet body has an annular recess whose axis is aligned parallel to the rotational axis of the electric motor's rotor shaft. An electrically energizable coil is housed in the annular recess.

[0038] An externally toothed annular driver is placed on the rotor shaft and connected to the rotor shaft in a rotationally fixed manner, in particular by means of a key connection.

[0039] A ring-disk-shaped brake pad carrier is placed on the driver, the internal teeth of which engage with the external teeth of the driver, so that the brake pad carrier is connected in a rotationally fixed manner to the driver and thus to the rotor shaft and is arranged to be axially movable.

[0040] The brake pad carrier is equipped with brake pads on both axial sides.

[0041] A ferromagnetic armature disk is arranged axially between the brake pad carrier and the magnet body. The armature disk is connected to the magnet body in a rotationally fixed manner.

[0042] In addition, the armature disk is arranged for axial movement. For this purpose, bolts protrude through recesses in the armature disk and are inserted into recesses or drilled holes in the magnet body.

[0043] A braking surface is formed on the bearing plate 1.

[0044] Spring elements supported on the magnet body press on the armature disc.

[0045] Thus, when the coil is energized, the armature disk is pulled toward the magnet body 2 against the spring force generated by the spring elements. However, when the coil is de-energized, the armature disk is pushed toward the brake lining carrier by the spring elements, which then presses the brake surface formed on the bearing plate 1, which is located on the side of the brake lining carrier facing away from the armature disk. Thus, the brake is released when the coil is energized, and applied when the coil is de-energized.

[0046] A cover 4 is attached to the bearing plate 1, with a flat seal 21 arranged between the cover 4 and the bearing plate 1 to ensure a tight connection between the cover 4 and the bearing plate 1. The bearing plate 1 also forms the housing of the electric motor.

[0047] The long screws are arranged radially within the radial distance area covered by the hood 4.

[0048] The threaded rods 3 are arranged radially within the radial distance area covered by the hood 4.

[0049] The bolts are arranged radially within the radial distance area covered by the hood 4.

[0050] The axial direction is aligned parallel to the rotational axis of the rotor shaft and the radial direction, the circumferential direction and the radial distances are each related to the rotational axis of the rotor shaft of the electric motor.

[0051] The area covered by the brake pad carrier in the axial direction is arranged within the area covered by the hood 4 in the axial direction.

[0052] The area covered by the magnetic body 2 in the axial direction is arranged within the area covered by the hood 4 in the axial direction.

[0053] The area covered by the armature disk in the axial direction is arranged within the area covered by the hood 4 in the axial direction.

[0054] The radial clearance area covered by the magnet body 2, the armature disc, and the brake pad carrier is contained in the radial clearance area covered by the cover 4. The cover 4 thus surrounds the brake, with the interior space surrounding the brake and enclosed by the cover 4 being sealed by the flat seal 21 and the sealing rings 20.

[0055] To reduce vibrations and increase rigidity, the outer circumference of the hood 4 is composed of four areas, each of these areas being a cylinder jacket section whose cylinder radius is greater than half the largest outer diameter of the hood 4.

[0056] In this way, the hood 4 has a rounded, polygonal appearance, allowing liquids to drain quickly and achieving high rigidity combined with low vibration. Furthermore, the largest possible volume of the enclosed interior space can be achieved. The wall thickness of the hood 4 is preferably constant.

[0057] The area covered by each of the cylinder sections in the circumferential direction is the same size. The cylinder axis is parallel to, but spaced from, the rotational axis of the rotor shaft.

[0058] In further embodiments according to the invention, the hood is composed of a different number of cylinder jacket sections, three, five, six, seven or eight, instead of four.

[0059] The area covered by each of the cylinder shell sections in the circumferential direction is again the same size. The cylinder axis is also parallel to, but spaced from, the rotational axis of the rotor shaft.

[0060] In further embodiments according to the invention, a threaded rod with nuts is used instead of the long screw with screw head.

[0061] In further embodiments according to the invention, the driver and the rotor shaft are designed as one piece, i.e. the external toothing is designed directly on the rotor shaft.

[0062] In further embodiments according to the invention, the braking surface is formed on a sheet metal part, in particular a friction plate, which is connected in a rotationally fixed manner to the bearing plate and which is arranged axially between the bearing plate and the lining carrier.

[0063] List of reference symbols

[0064] 1 bearing shield 2 magnet body

[0065] 3 threaded rods

[0066] 4 hood

[0067] 5 Stator housing

[0068] 6 bearing flange 20 sealing ring

[0069] 21 Flat gasket

Claims

Patent claims:

1. Electric motor, wherein the electric motor has a stator housing which is connected on the one hand to a bearing plate of the electric motor receiving a bearing of the rotor shaft of the electric motor and on the other hand to a bearing flange receiving a further bearing of the rotor shaft, wherein a magnetic body of an electromagnetically actuated brake of the electric motor is connected in a rotationally fixed manner to the bearing plate, in particular wherein the magnetic body is arranged on the side of the bearing plate axially facing away from the stator housing, characterized in that a hood surrounds the magnetic body in a housing-forming, in particular watertight and / or airtight manner, and is pressed onto the bearing plate via an intermediate seal, in particular a flat seal, in particular by screw heads of screws, in particular whose threaded area is screwed into threaded holes in the bearing plate.

2. Electric motor according to claim 1, characterized in that at least one screwing means, in particular a long screw, screw or threaded rod, projects through the bearing flange, the stator housing and the bearing plate and the bearing plate is or is pressed towards the stator housing by means of a screw head of the screwing means or a nut screwed onto the screwing means and the bearing flange is or is pressed towards the stator housing by means of a screw head of the screwing means or a nut screwed onto the screwing means.

3. Electric motor according to one of the preceding claims, characterized in that a sealing ring is placed on the screw means and rests against the bearing plate, the screw head or the nut pressing onto the bearing plate via the sealing ring.

4. Electric motor according to one of the preceding claims, characterized in that the hood has cylinder jacket sections which are adjacent to one another in the circumferential direction.

5. Electric motor according to one of the preceding claims, characterized in that the areas covered by the respective cylinder jacket sections in the circumferential direction are each of the same size.

6. Electric motor according to one of the preceding claims, characterized in that the cylinder axis of the respective cylinder jacket section is aligned parallel to the axis of rotation of the rotor shaft of the electric motor and is spaced from the axis of rotation of the rotor shaft of the electric motor.

7. Electric motor according to one of the preceding claims, characterized in that the radius of the respective cylinder jacket section is in each case greater than half the largest outer diameter of the hood and / or that the radius of the respective cylinder jacket section is in each case greater than the largest radial distance of the hood relative to the axis of rotation of the rotor shaft.

8. Electric motor according to one of the preceding claims, characterized in that the wall thickness of the hood is constant and / or that the wall thickness of the hood is independent of the circumferential direction.

9. Electric motor according to one of the preceding claims, characterized in that the screw means protrude from the bearing plate into the interior area surrounded by the hood.

10. Electric motor according to one of the preceding claims, characterized in that the threaded rods project axially through the magnetic body and the threaded rods project axially from the magnetic body on both sides, in particular wherein a further magnetic body of a further brake can be fastened to the threaded rods projecting from the magnetic body.

11. Electric motor according to one of the preceding claims, characterized in that an annular externally toothed driver is placed on the rotor shaft and connected to the rotor shaft in a rotationally fixed manner, in particular by means of a key connection, wherein an annular disc-shaped brake pad carrier is placed on the driver and engages with its internal toothing with the external toothing of the driver, so that the brake pad carrier is arranged in a rotationally fixed manner with the driver and axially displaceable relative to the driver, wherein an energizable coil is accommodated in an annular recess of the magnetic body, wherein an armature disk is arranged axially between the magnetic body and the brake pad carrier, wherein the armature disk is connected to the magnetic body in a rotationally fixed manner, wherein the armature disk is arranged in an axially movable manner, in particular by means of recesses in the armature disk projecting, in particular axially directed,Bolts are pressed into recesses in the magnetic body, wherein the armature disc is arranged on the side of the brake pad carrier axially remote from the bearing plate, wherein spring elements supported on the magnetic body and spaced apart from one another in the circumferential direction press on the armature disc, in particular wherein a braking surface is formed on the bearing plate.

12. Electric motor according to one of the preceding claims, characterized in that when the coil is energized, the armature disc is pulled towards the magnetic body against the spring force generated by the spring elements.

13. Electric motor according to one of the preceding claims, characterized in that when the coil is not energized, the armature disc is pressed by the spring elements onto the brake pad carrier and thus the brake pad carrier is pressed onto the braking surface formed on the bearing plate or onto a friction plate fastened to the bearing plate and having a braking surface.

14. Electric motor according to one of the preceding claims, characterized in that the armature disc and the brake pad carrier are surrounded by the hood and / or are arranged in the interior region surrounded by the hood.

15. Electric motor according to one of the preceding claims, characterized in that the hood is designed as a plastic injection-molded part.

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