Electric motor with stator housing and cover part

Abstract

An electric motor, in particular a geared motor, comprising a stator housing and a cover part, wherein respective block regions protruding axially on both sides are formed on the cover part, and wherein the end face of the cover part facing axially away from the stator housing is of rotationally symmetrical configuration.

Description

[0001] Electric motor, in particular geared motor, with stator housing and cover part

[0002] Description:

[0003] The invention relates to an electric motor, in particular a geared motor, with stator housing and cover part.

[0004] It is generally known that an electric motor has a stator housing and a rotor that is rotatably mounted relative to the stator. The axial direction of the rotor is aligned parallel to its axis of rotation.

[0005] From CN 1 02599851 B, an electric motor is known as the closest state of the art.

[0006] From DE 102018001 086 A1 a drive comprising an electric motor and a gearbox is known.

[0007] From DE 102022004446 A1 an electric motor with electromagnetically actuated brake is known.

[0008] An engine is known from CN 1 04218717 B.

[0009] From DE 102019008413 A1 an electric motor with a stator housing is known.

[0010] The invention is therefore based on the objective of further developing an electric motor that offers increased environmental protection.

[0011] According to the invention, the problem is solved in the electric motor according to the features specified in claim 1.

[0012] Important features of the invention for the electric motor with stator housing and cover part are that respective block areas, projecting axially on both sides, in particular through-holes, are formed on the cover part.

[0013] ISI \ EIDOPAT 29.01.2026, wherein the end face of the cover part facing axially away from the stator housing is rotationally symmetric, in particular not discrete, but continuously rotationally symmetric,

[0014] in particular wherein the electric motor has a rotatably mounted rotor.

[0015] An advantage of this design is that the block areas enable stable attachment of the cover to the stator housing, particularly using screws. Furthermore, the acoustic radiation of structure-borne noise transmitted from the stator housing to the cover during operation of the electric motor is reduced, as the block areas suppress vibration modes of the cover. The otherwise rotationally symmetrical design of the outer surface of the cover allows for a bell-shaped design of the cover.

[0016] This allows for specific vibration patterns, which are, however, suppressed by the block sections being spaced apart from each other around the circumference. This results in reduced acoustic radiation and thus improved environmental protection.

[0017] In an advantageous embodiment, the end face of the cover part axially facing the stator housing is discretely rotationally symmetric, i.e., it exhibits discrete rotational symmetry. It is advantageous that the symmetries of the outer and inner surfaces of the cover part differ from each other, thereby suppressing vibration modes. In particular, rib structures formed on the inside of the cover part stiffen it and thus suppress vibration modes of the cover part.

[0018] In an advantageous embodiment, the end face of the cover part axially facing the stator housing is discretely rotationally symmetric with respect to rotations of 3607n, where n is the number of block areas. This has the advantage of suppressing vibration modes and thus reducing acoustic radiation.

[0019] In an advantageous embodiment, the cover part has an annular wall on its radial outer circumference, and an annular region is formed on the cover part, which is arranged radially within the annular wall and is aligned and / or arranged concentrically to the annular wall, in particular wherein the annular axes of the annular region and the annular wall are aligned coaxially with each other. It is advantageous that the annular region projects axially on the inside of the cover part and covers an axial area that overlaps with the area covered by the annular wall in the axial direction. In an advantageous embodiment, an axially through-hole is formed in each block area.

[0020] In particular, a screw protrudes through the recess and its threaded section is screwed into a respective axially directed threaded bore, and in particular, the screw head presses the cover part towards the stator housing. It is advantageous that the cover part can be fastened to the stator housing with screws, and that the cover part can withstand high forces.

[0021] In an advantageous embodiment, ribs are formed on the side of the cover facing the stator housing, each extending from the ring area to the ring wall. This is advantageous because it results in reduced acoustic emissions, particularly from the cover.

[0022] In an advantageous embodiment, the ribs project axially from the cover part towards the stator housing. It is advantageous that a stiffening rib structure is located on the inside of the cover part.

[0023] In an advantageous embodiment, the projection of each rib on the ring area is spaced circumferentially from the projection of that rib on the ring wall. It is advantageous that the ribs are inclined and thus not only radially oriented. This results in stiffening and therefore suppression of vibration modes, leading to reduced sound radiation.

[0024] In an advantageous embodiment, a projection of a second rib is formed at the base of each first rib formed on the ring wall, wherein the projection of the second rib formed on the ring area is spaced circumferentially apart from the projection of the first rib formed on the ring area. It is advantageous that the rib pairs are not parallel.

[0025] In an advantageous embodiment, the circumferential distance between the projection of the first rib on the annular region and the projection of the second rib on the annular region is twice the circumferential distance between the projection of the first rib on the annular region and the projection of the first rib on the annular wall. It is advantageous that the ribs do not extend purely radially, but rather obliquely, thus suppressing many vibration modes of the cover section. It is important that the annular region projects axially from the inside of the cover section towards the stator housing.

[0026] In an advantageous embodiment, a seal is arranged between the cover part and the stator housing and / or the cover part is tightly connected to the stator housing.

[0027] In an advantageous embodiment, the block sections are uniformly spaced from one another in the circumferential direction, in particular at an angular distance of 360° / n to their nearest circumferentially adjacent block sections, where n is the number of block sections. An advantage of this is that the acoustic emission can be reduced.

[0028] In a preferred embodiment, the lid part is made as a casting. The advantage here is that it allows for simple manufacturing.

[0029] In an advantageous embodiment, with the exception of the block areas, the maximum outer diameter of the cover part decreases monotonically, and in particular strictly monotonically, with increasing distance from the stator housing. An advantage of this is that the acoustic emission can be reduced.

[0030] In an advantageous embodiment, the number n of block areas is three or four. An advantage of this is the particularly low acoustic radiation.

[0031] In an advantageous embodiment, the first derivative of the maximum outer diameter of the cover part as a function of the axial distance to the stator housing exhibits a change of sign at a first outer diameter.

[0032] wherein the first outer diameter, associated with the change of sign, is smaller than the outer diameter of the ring wall and larger than the outer diameter of the ring area. It is advantageous that the cover part is bell-shaped on the outside and stiffened on its inside, i.e., the side facing the stator housing, with a discretely symmetrical rib structure. In this way, the acoustic radiation is reduced because the bell vibrations are suppressed. Further advantages arise from the dependent claims. The invention is not limited to the combination of features of the claims. For those skilled in the art, further meaningful combinations of claims and / or individual claim features and / or features of the description and / or the figures will arise, in particular from the problem statement and / or the problem arising from a comparison with the prior art.The invention will now be explained in more detail with reference to a schematic illustration.

[0033] Figure 1 shows a cover part of an electric motor according to the invention, in particular a geared motor, in an oblique view.

[0034] Figure 2 shows the lid part in a top view, in particular on the inside.

[0035] Figure 3 shows a cross-section of the lid part.

[0036] Figure 4 shows the electric motor according to the invention, in particular the geared motor, in an oblique view.

[0037] Figure 5 shows the electric motor, in particular the geared motor, in longitudinal section.

[0038] As shown in the figures, the electric motor, in particular the geared motor, has a stator housing 40 that is open on both sides axially and surrounds the stator winding of the electric motor. The stator winding radially surrounds the rotatably mounted rotor of the electric motor.

[0039] The axial direction is aligned parallel to the rotor's axis of rotation. The radial direction and radial distances are also relative to the rotor's axis of rotation. The circumferential direction is likewise relative to the rotor's axis of rotation.

[0040] The cover part 1 is connected to the stator housing 40 and thus closes one of the two axial openings of the stator housing 40.

[0041] For this purpose, screws protrude through circumferentially spaced block sections 3 of the cover part 1, are screwed with their respective threaded sections into axially oriented threaded bores in the stator housing, and their screw heads press the cover part 1 towards the stator housing. The cover part 1 is tightly connected to the stator housing by means of an intermediate seal.

[0042] The block areas 3 are designed as thickenings of the cover part 1, which is rotationally symmetrical on its side facing away from the stator housing, except for the block areas 3 which project axially on both sides of the cover part 1, and in particular has a continuous rotational symmetry with respect to the axis of rotation of the rotor of the electric motor.

[0043] In contrast, the cover part 1 exhibits a discrete rotational symmetry with respect to the axis of rotation of the rotor of the electric motor on its inner side, i.e., on its side facing the stator housing. This rotational symmetry is preferably 360° / n, where n is the number of block sections 3. A number of three block sections 3 is particularly preferred.

[0044] The block sections 3 are all arranged at the same axial position and at the same radial distance from the axis of rotation of the rotor of the electric motor. In the circumferential direction, the block sections 3 are uniformly spaced from one another; in particular, their circumferential position differs by 360° / n or an integer multiple thereof.

[0045] On its inner side, the cover part 1 has a ring area 2 that projects axially towards the stator housing. The ring axis of the ring area 2 is aligned coaxially with the axis of rotation of the rotor.

[0046] The cover part 1 has an annular wall 5 at its radial outer edge, with block areas 3 extending radially inwards from the annular wall 5, and ribs 4 extending from the annular wall 5 to the annular area 2. However, the direction of extension of the ribs 4 is not purely radial. Thus, the projection of each rib 4 located on the annular wall 5 is spaced circumferentially apart from the projection of this respective rib 4 on the annular area 2.

[0047] The ring wall 5 and the ring area 2 are aligned concentrically with each other.

[0048] In particular, their ring axes are aligned coaxially with each other.

[0049] A first rib is arranged circumferentially between the block sections 3, the projection of which on the ring wall 5 is spaced circumferentially apart from the projection of this respective rib 4 on the ring section 2. A second rib 4 is formed on the cover part 1 for each of these first ribs 4, which has the same projection on the ring wall 5 as the respective first rib 4 and whose projection on the ring section 2 is spaced opposite to the circumferential direction by the same amount as the projection of the respective first rib 4 on the ring section 2 is to the projection of the respective first rib 4 on the ring wall 5. The cover part is preferably made of metal, in particular as a casting.

[0050] Each block section 3 has a trapezoidal outer circumference on its end face facing the stator housing 40, with the base, i.e., the longer of the two parallel base sides of the trapezoid, arranged radially outside the shorter of the two base sides of the trapezoid. In this way, the cover part 1 can be made compact and rigid, and the block sections 3 can withstand high loads from the screws.

[0051] As the distance from the stator housing increases, the outer diameter of the cover part decreases monotonically, or in further development even strictly monotonically.

[0052] The lid part, together with the ring wall 5, the ring area 2 and the ribs 4, is made in one piece.

[0053] In further embodiments of the invention, the lid part is manufactured as a plastic injection-molded part. Reference numeral list

[0054] 1 lid part

[0055] 2 ring area

[0056] 3 block area

[0057] 4th rib

[0058] 5 Ring wall

[0059] 40 Stator housings

Claims

Patent claims:

1. Electric motor, in particular geared motor, with stator housing and cover part, in particular wherein the electric motor has a rotatably mounted rotor, characterized by the fact that The lid section has block areas that project axially on both sides, in particular through sections. wherein the end face of the cover part facing axially away from the stator housing is rotationally symmetrical, in particular not discretely, but continuously rotationally symmetrical.

2. Electric motor according to claim 1, characterized by the fact that The end face of the cover part, which faces axially towards the stator housing, is discretely rotationally symmetrical, i.e., it has a discrete rotational symmetry.

3. Electric motor according to any of the preceding claims, characterized by the fact that the end face of the cover part axially facing the stator housing is discretely rotationally symmetric with respect to rotations by 3607n, where n is the number of block areas.

4. Electric motor according to any of the preceding claims, characterized by the fact that the lid part has an annular wall on its radial outer circumference and a ring area is formed on the lid part which is arranged radially inside the annular wall and is aligned and / or arranged concentrically to the annular wall, in particular wherein the ring axes of the annular area and the annular wall are aligned coaxially to each other.

5. Electric motor according to any of the preceding claims, characterized by the fact that In each block area, an axially continuous recess is formed, in particular wherein a respective screw protrudes through the recess and is screwed into a respective axially directed threaded bore with its threaded area, in particular wherein the screw head of the screw presses the cover part towards the stator housing.

6. Electric motor according to any of the preceding claims, characterized by the fact that On the side of the cover part facing the stator housing, ribs are formed on the cover part, each extending from the ring area to the ring wall.

7. Electric motor according to any of the preceding claims, characterized by the fact that the ribs project axially towards the stator housing on the cover part.

8. Electric motor according to one of the preceding claims, characterized by the fact that The projection of the respective rib formed on the ring area is spaced in the circumferential direction from the projection of this respective rib formed on the ring wall.

9. Electric motor according to any of the preceding claims, characterized by the fact that At the attachment point of each first rib on the ring wall, an attachment point of each second rib is formed, wherein the attachment point of the second rib formed on the ring area is spaced circumferentially from the attachment point of the first rib formed on the ring area.

10. Electric motor according to any of the preceding claims, characterized by the fact that The circumferential distance between the projection of the first rib formed on the ring area and the projection of the second rib formed on the ring area is twice the circumferential distance between the projection of the first rib formed on the ring area and the projection of the first rib formed on the ring wall.

11. Electric motor according to any of the preceding claims, characterized by the fact that A seal is arranged between the cover part and the stator housing and / or the cover part is tightly connected to the stator housing.

12. Electric motor according to any of the preceding claims, characterized by the fact that the block parts are uniformly spaced apart from each other in the circumferential direction, in particular with an angular distance of 360° / n to their nearest neighboring block parts in the circumferential direction, where n is the number of block parts.

13. Electric motor according to any of the preceding claims, characterized by the fact that The cover part is designed as a casting.

14. Electric motor according to one of the preceding claims, characterized by the fact that except for the block areas, the maximum outer diameter of the cover part decreases monotonically, in particular strictly monotonically, with increasing distance from the stator housing. and / or that The number n of block areas is three or four.

15. Electric motor according to any of the preceding claims, characterized by the fact that the first derivative of the maximum outer diameter of the cover part as a function of the axial distance to the stator housing exhibits a sign change at a first outer diameter, where the first outer diameter, which corresponds to the change of sign, is smaller than the outer diameter of the ring wall and larger than the outer diameter of the ring area.

Images