Bearing seat for a shaft bearing and motor vehicle

Abstract

The invention relates to a bearing seat (12) for a shaft bearing (14), having a radial wall (22) and an axial wall (18), which are aligned obliquely or perpendicularly to one another and adjoin one another in a connecting region (20), wherein an undercut (24) forming a notch is provided in the connecting region (20), wherein a cross-sectional contour (26) of the undercut (24) comprises a load region (30) and at least one connecting region (32, 34) having a curvature, wherein a notch root of the notch is arranged in the load region (30) such that a maximum stress occurring in the notch during operation occurs in the load region (30), wherein for stress homogenization the load region (30) is designed with a smaller curvature than the at least one connecting region (32, 34).

Description

[0001] The invention relates to a bearing seat for a shaft bearing and a motor vehicle with a bearing seat.

[0002] WO 2022 / 089684 A1 discloses an electric machine comprising a stator and a rotor housed in a motor housing. The rotor is rotatably mounted relative to the stator by means of two axially spaced-apart rolling bearings. The respective rolling bearings comprise an inner ring, which is non-rotatably connected to the rotor via a first bearing seat, and an outer ring, which is non-rotatably connected to the motor housing via a second bearing seat.

[0003] Furthermore, EP 2 459 893 B1 discloses a rolling bearing for a dual-mass flywheel in a motor vehicle.

[0004] The object of the present invention is to provide a solution which enables a particularly high robustness of a bearing seat in a notch forming undercut.

[0005] This object is achieved according to the invention by the subject matter of the independent claims. Further possible embodiments of the invention are disclosed in the subclaims, the description, and the figures. Features, advantages, and possible embodiments presented in the description for one of the subject matter of the independent claims are to be regarded at least analogously as features, advantages, and possible embodiments of the respective subject matter of the other independent claims, as well as any possible combination of the subject matter of the independent claims, optionally in conjunction with one or more of the subclaims.

[0006] The invention relates to a bearing seat for a shaft bearing, which can in particular be part of a motor vehicle. The shaft bearing can, for example, be a rolling bearing which is designed to be fastened to the bearing seat. A shaft can in turn be rotatably mounted by means of the shaft bearing. The bearing seat can, in particular, be pot-shaped. The bearing seat comprises a radial wall and an axial wall which are aligned obliquely or perpendicular to one another and adjoin one another in a connecting region. For example, the axial wall can form the base of the pot and the radial wall can form the wall of the pot. Depending on the helix angle at which the radial wall is arranged to the axial wall, a receptacle delimited by the bearing seat, in which the shaft bearing can be accommodated, can decrease or increase in cross-section from the base and thus from the axial wall to an opening in the pot, or can remain constant.In particular, the axial direction of the bearing seat is perpendicular to the axial wall. The radial direction of the bearing seat is perpendicular to the axial direction.

[0007] An undercut forming a notch is provided in the connecting area. This undercut allows the shaft bearing, if arranged in the bearing seat, to be pushed into the bearing seat until it rests against the axial wall and / or the radial wall. In principle, such a connecting area could be a simple radius. The term undercut is used when it refers to the clearances for machining tools. When manufacturing the bearing seat, first the axial surface and then the radial surface are produced. This notch runs in particular over the entire length of the connecting area, with the length of the connecting area corresponding to the length of adjacent edges of the radial wall and the axial wall. In particular, the bearing seat is monolithic, which means that the radial wall and the axial wall are formed integrally with one another.

[0008] An undercut is a removal of material from a rotationally symmetrical inner edge with a specific shape and specified dimensions. This undercut serves to provide the necessary clearance for the shaft bearing when inserting it into the bearing seat. This undercut is an internal undercut.

[0009] It is provided that a cross-sectional contour of the undercut comprises a load area and at least one connecting area having a curvature. The load area forms a notch root of the notch, so that any maximum stress occurring in the notch during operation occurs in the load area. This notch root is a point of the undercut which is subject to the highest levels of stress. It must be avoided that the bearing seat breaks at this notch root due to tension or strain. To homogenise the stress, the load area is designed with a smaller curvature than the at least one connecting area. By homogenising the stress, local overloading of the bearing seat in the area of ​​the notch can be particularly effectively avoided, which in turn can particularly low the risk of failure of the bearing seat during operation.The particularly large radius of the loading area allows the highest mechanical stress to act on a loading surface instead of a loading point on the cross-sectional contour of the undercut, thereby ensuring that the highest mechanical stress acting in the loading area is particularly low. The notch root is located in the loading area. In particular, the loading area is designed such that the notch root is centrally located in the loading area with respect to the cross-sectional contour of the undercut. In this case, the undercut is, in particular, a radial undercut without a recess into the axial wall.

[0010] The contour of the undercut thus has a load area in cross-section and at least one curved connecting area. The cross-section is understood to be a section of the undercut parallel to a plane spanned by the axial direction A and the radial direction R. In this case, the cutting plane runs in particular through an axial center axis of the bearing seat. A load point of the contour in the cross-section, which is subject to the highest mechanical stress during operation, is located in the load area. To homogenize stress, the load area is less curved than the at least one connecting area.Because the load area is less curved than at least one connection area, it can be achieved that stresses introduced in the load area during operation of the bearing seat are distributed over the entire load area, thereby achieving stress homogenization. As a result of stress homogenization, the introduced force now acts on the entire load area, whereby a particularly low ratio of maximum force to area can be achieved and, as a result, a particularly low maximum mechanical load on the bearing seat in the notch formed by the undercut is achieved. As a result, mechanical stress on the bearing seat in the notch is particularly low, which in turn reduces the risk of bearing seat failure.

[0011] In a possible development of the invention, it is provided that the load area extends over at least one-third, in particular over at least half the length of the cross-sectional contour of the undercut. The load area thus extends over a particularly large proportion of the cross-sectional contour of the undercut. The slight curvature of the load area compared to the connecting area and the large proportion of the load area in the cross-sectional contour of the undercut mean that mechanical stresses introduced into the notch of the bearing seat during operation are distributed over a particularly large area in the notch, whereby the maximum stress acting at a point of highest load in the notch is particularly low. As a result, the risk of damage to the bearing seat during operation is particularly low.

[0012] In a further possible embodiment of the invention, it is provided that both the loading area and the connection area are curved with two mutually different radii and with the same direction of curvature, or that the loading area is straight. The smaller the curvature of the loading area, the larger the area of ​​the cross-sectional contour of the undercut can be selected, over which mechanical stresses introduced into the notch are distributed. Because the connection area is curved in the same direction of curvature as the loading area, provided the loading area is curved, and has a smaller radius than the loading area, the connection area can be designed with a particularly short length in relation to the cross-sectional contour of the undercut and connect the loading area to an edge of the cross-sectional contour of the undercut.As a result, the load area can extend over a particularly large area of ​​the cross-sectional contour of the undercut, which in turn allows the stresses introduced into the notch to be distributed over the particularly large load area, which in turn allows the stress per unit area in the notch to be kept particularly low.

[0013] In a further possible embodiment of the invention, it is provided that the cross-sectional contour has two connecting regions with the same direction of curvature, wherein the load region arranged along the cross-sectional contour between the two connecting regions has the smallest curvature or is straight. Because the two connecting regions each have the same direction of curvature, in particular the same direction of curvature as the load region, provided the load region is curved, it can be achieved that the cross-sectional contour of the relief groove forms an undercut, whereby the notch root extends over a particularly large area of ​​the cross-sectional contour, in particular over the entire load region. As a result, the maximum stress occurring per unit area in the notch during operation can be kept particularly low.

[0014] In a further possible embodiment of the invention, it is provided that the radius of the loading area is at least 1.5 times, in particular at least 3 times, in particular at least 5 times as large as the largest radius of the at least one connection area of ​​the cross-sectional contour. If the cross-sectional contour thus has two further connection areas, then the loading area is at least 1.5 times, in particular at least 3 times, in particular at least 5 times as large as the radius of the connection area having the larger radius. The larger the radius of the loading area, the more evenly a force acting in the notch, in particular mechanical stress, can be distributed, whereby the maximum stress occurring in the notch per unit area can be kept particularly low.

[0015] In a further possible embodiment of the invention, it is provided that a radial penetration depth of the cross-sectional contour of the undercut is at least as large as the radius of the connection region, which is arranged along the cross-sectional contour of the undercut on the side of the load region facing the radial wall. The radial penetration depth of the cross-sectional contour of the undercut is to be understood as how deep the undercut extends in the radial direction into the radial wall. The deeper the undercut extends into the radial wall, the longer the load region can be designed in relation to the cross-sectional contour and, consequently, the larger the area over which mechanical stresses introduced into the notch can be distributed in the load region.

[0016] In a further possible embodiment of the invention, it is provided that the undercut has its greatest radial penetration depth in the region of the connection region, which is arranged along the cross-sectional contour of the undercut on the side of the load region facing the radial wall. This connection region can provide a transition from the load region to a side surface of the radial wall in relation to the cross-sectional contour. This in turn can ensure that the portion of the cross-sectional contour assigned to the load region is particularly large, in particular if the load region directly adjoins the connection region, which is assigned to the greatest radial penetration depth of the undercut and extends as far as a side surface of the radial wall delimiting the radial wall in relation to the cross section.

[0017] In a further possible embodiment of the invention, it is provided that the undercut in the connection area, which is arranged along the cross-sectional contour of the undercut on the side of the load area facing the radial wall, has a radius of 0.8 millimeters, in the connection area, which is arranged along the cross-sectional contour of the undercut on the side of the load area facing the axial wall, has a radius of 0.9 mm, in the load area has a radius of at least 3 mm, has a radial recess depth of 0.8 mm and extends over a height of 2.6 mm in the axial direction. With the dimensions mentioned, particularly good stress homogenization of mechanical stresses introduced into the notch can be achieved, whereby the risk of failure of the bearing seat during operation can be kept particularly low.

[0018] In a further possible embodiment of the invention, it is provided that the bearing seat is designed to support a motor vehicle shaft by means of the shaft bearing. The motor vehicle shaft can in particular be a transmission shaft, in particular an intermediate shaft of the motor vehicle. The bearing seat is thus designed to accommodate the shaft bearing and to absorb forces acting on the bearing seat via the shaft bearing when the motor vehicle shaft, which is supported by the shaft bearing, rotates. In particular, the bearing seat can be part of a drive housing of the motor vehicle, in particular part of a transmission housing of the motor vehicle. The bearing seat is in particular designed to transmit forces introduced into the bearing seat by the motor vehicle shaft into the transmission housing via the shaft bearing during operation. By means of the described bearing seat, the motor vehicle shaft can thus be supported particularly securely and with minimal damage.

[0019] The invention further relates to a motor vehicle with a bearing seat as already described in connection with the bearing seat according to the invention. In particular, the bearing seat is part of a motor vehicle component, in particular part of a drive housing and a drive of the motor vehicle.

[0020] The motor vehicle may in particular be a motor vehicle, in particular a passenger car.

[0021] Further features of the invention may emerge from the claims, the figures, and the description of the figures. The features and combinations of features mentioned above in the description, as well as the features and combinations of features shown below in the description of the figures and / or in the figures alone, can be used not only in the respective combinations specified, but also in other combinations or on their own, without departing from the scope of the invention.

[0022] The drawing shows: Fig. 1 is a schematic, partially sectioned view of a bearing seat in which a shaft bearing is held, the bearing seat having a notch formed by an undercut; Fig. 2 a sectional view of the bearing seat in the area of ​​the undercut; and Fig. 3 a partially sectioned schematic perspective view of the undercut of the bearing seat.

[0023] In the figures, identical and functionally identical elements are provided with the same reference numerals.

[0024] In Fig. 1 shows a bearing seat 12 arranged on a housing cover 10 of a drive housing of a motor vehicle. The drive housing is designed, in particular, to enclose at least a part of a drive of the motor vehicle, in particular at least one transmission of the motor vehicle. The bearing seat 12 is designed, in this case, to receive a shaft bearing 14 and thereby position it. The shaft bearing 14 is designed, in this case, as a rolling bearing, wherein Fig. 1, only an outer ring 16 of the rolling bearing is shown. By means of the shaft bearing 14, a rotating shaft, in particular a transmission shaft, can be mounted on the bearing seat 12. In particular, the bearing seat 12 is a die-cast aluminum component.

[0025] The bearing seat 12 is pot-shaped in the present case and has an axial wall 18 and a radial wall 22 connected to the axial wall 18 via a connecting region 20. On the axial wall 18, as in Fig. 1, an axial end face of the shaft bearing 14 when used as intended. The radial wall 22 lies against a radial outer side, in particular a radial outer surface of the shaft bearing 14, when used as intended. The radial wall 22 adjoins the axial wall 18 in the axial direction A. In the present case, the axial wall 18 and the radial wall 22 are aligned perpendicular to one another. In order to enable the outer ring 16 to lie flat against both the axial wall 18 and the radial wall 22 of the bearing seat 12, a radial undercut 24 forming a notch is provided in the radial wall 22. The area of ​​the bearing seat 12 having the undercut 24 is in Fig. 1 in an enlarged cross-section. The undercut 24 is also shown in the Fig. 2 and Fig. 3 is shown enlarged. In the Fig. 2 and Fig. 3, a cross-sectional contour 26 of the undercut 24 can be seen particularly well. In particular, the undercut 24 has this in the Fig. 2 and Fig. 3 shown cross-sectional contour 26 over its entire length. In other words, the undercut 24 has over its entire length the Fig. 2 and Fig. 3. In particular, the undercut 24 extends circumferentially along an entire lower edge of a receptacle 28 of the bearing seat 12, wherein the lower edge extends annularly around the outer ring 16. The receptacle 28 is bounded by the axial wall 18 and the radial wall 22 and is configured to accommodate the shaft bearing 14 when used as intended.

[0026] Along the cross-sectional contour 26, the undercut 24 in this case has a load region 30, a first connection region 32 and a second connection region 34. In this case, the cross-sectional contour 26 additionally has a straight transition region 36. The transition region 36 extends from point A to point B. Point A describes a point in the cross-section at which a relief-free region of the radial wall 22 ends and the undercut 24 begins. The first connection region 32 extends from point B to point C. The load region 30 extends from point C to point D. The second connection region 34 extends from point D to point E. Point E here delimits the cross-sectional contour 26 of the undercut 24 to a relief-free region of the axial wall 18.

[0027] The cross-sectional contour 26 is designed such that the highest stress occurring in the notch occurs in the loading area 30. This means that the notch root is arranged in the loading area 30. In order to ensure that the maximum force acting in the loading area 30, in particular a maximum mechanical stress, is distributed over a particularly large area of ​​the notch and thus over a particularly large area of ​​the cross-sectional contour 26 for stress homogenization. In order to ensure that any stress peaks that occur are only particularly small, it is provided that, on the one hand, the loading area 30 extends over a particularly large proportion of the length of the cross-sectional contour 26 and, in addition, the loading area 30 has a particularly slight curvature for a particularly even distribution of acting mechanical stresses over the entire loading area 30.In order that the loading region 30 can extend over a particularly large area of ​​the cross-sectional contour 26 and, in addition, can have a particularly small curvature, it is provided that in the present case the connection regions 32, 34 have the same direction of curvature, the loading region 30 is arranged between the two connection regions 32, 34 with respect to the cross-sectional contour 26 and the loading region 30 has a smaller curvature than the connection regions 32, 34, or the connection regions 32, 34 have a greater curvature than the loading region 30.Because the connection regions 32, 34 have a greater curvature than the loading region 30, which can either be curved with the same direction of curvature as the connection regions 32, 34 or can be straight, the transition from the loading region 30 to the respective ends at points A and E of the cross-sectional contour 26 can be implemented by the first connection region 32 in combination with the transition region 36 and by the second connection region 34, wherein at the same time the connection regions 32, 34 and the transition region 36 take up a particularly small proportion of the length of the cross-sectional contour 26, as a result of which the loading region 30 can extend over a particularly large proportion of the cross-sectional contour 26. In particular, it is provided that the loading region 30 extends at least over at least one third, in particular over at least half the length of the cross-sectional contour 26 of the undercut 24.The connection regions 32, 34 can have identical or different radii. In particular, it is provided that the radius of the load region 30 is at least 1.5 times, in particular at least 3 times, in particular at least 5 times as large as the larger of the radii of the two connection regions 32, 34. In particular, it is provided that a radial penetration depth 38 of the cross-sectional contour 26 of the undercut 24 is at least as large as the radius of the first connection region 32. The first connection region 32 is arranged along the cross-sectional contour 26 on the side of the load region 30 associated with the radial wall 22. In the present case, it is provided that the undercut 24 has its greatest radial penetration depth 38 in the region of the first connection region 32.

[0028] In this case, the first radius R1 of the first connection area 32 is 0.8 mm. The second radius R2 of the second connection area 34 corresponds to 0.9 mm. The third radius R3 of the load area 30 is 3 mm. The radial recess depth 38 is 0.8 mm. A height 40 of the undercut 24 extending in the axial direction A is 2.6 mm.

[0029] In particular, it is provided that the undercut 24 is introduced into the bearing seat 12 by milling. The cross-sectional contour 26 is therefore a milled contour on the bearing seat 12. The described design of the cross-sectional contour 26 makes it possible to achieve particularly low mechanical stress in the notch by distributing any mechanical stress that occurs evenly over a particularly large part of the cross-sectional contour 26 of the undercut 24. As a result, a particularly long service life of the bearing seat 12 can be achieved. The described cross-sectional contour 26 can be milled particularly easily as a radius or line on a cutting edge without any loss of cycle time. In particular, the undercut 24 explained in connection with the figures can be manufactured without an axial recess. To manufacture the undercut 24, a chamfer can first be milled into the connecting region 20.Subsequently, the undercut 24 can be created by radial grooving into the radial wall 22, in particular by milling. The described cross-sectional contour 26 of the undercut 24 enables the achievement of a particularly high local safety factor. As a result, a particularly long service life of the bearing seat 12 can be achieved with a particularly low risk of fatigue fracture. List of reference symbols 10 housing cover 12 bearing seat 14 shaft bearings 16 Outer ring 18 Axial wall 20 Connection area 22 Radial wall 24 undercut 26 Cross-sectional contour 28 recording 30 load range 32 first connection area 34 second connection area 36 Transition area 38 radial penetration depth 40 Height of the undercut A axial direction R radial direction R1 first radius R2 second radius R3 third radius QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] WO 2022 / 089684 A1

[0002] EP 2 459 893 B1

[0003]

Claims

[1] Bearing seat (12) for a shaft bearing (14), with a radial wall (22) and an axial wall (18), which are aligned obliquely or perpendicular to one another and adjoin one another in a connecting region (20), wherein an undercut (24) forming a notch is provided in the connecting region (20), wherein a cross-sectional contour (26) of the undercut (24) comprises a load region (30) and at least one connection region (32, 34) having a curvature, wherein a notch root of the notch is arranged in the load region (30) so that a maximum stress occurring in the notch during operation occurs in the load region (30), wherein for stress homogenization the load region (30) is designed with a smaller curvature than the at least one connection region (32, 34). [2] Bearing seat (12) according to claim 1, characterized bythat the loading area (30) extends at least over at least one third, in particular over at least half the length of the cross-sectional contour (26) of the undercut (24). [3] Bearing seat (12) according to claim 1 or 2, characterized by that both the loading area (30) and the connection area (32, 34) are curved with two different radii and with the same direction of curvature, or that the loading area (30) is straight. [4] Bearing seat (12) according to one of the preceding claims, characterized by that the cross-sectional contour (26) has two connecting regions (32, 34) with the same direction of curvature, wherein the loading region (30) arranged along the cross-sectional contour (26) between the two connecting regions (32, 34) has the smallest curvature or is straight. [5] Bearing seat (12) according to one of the preceding claims, characterized bythat the radius (R3) of the loading region (30) is at least 1.5 times, in particular at least 3 times, in particular at least 5 times as large as the largest radius (R1, R2) of the at least one connection region (32, 34). [6] Bearing seat (12) according to one of the preceding claims, characterized by that a radial penetration depth (38) of the cross-sectional contour (26) of the undercut (24) is at least as large as the radius (R1) of the connection region (32) which is arranged along the cross-sectional contour (26) of the undercut (24) on the side of the loading region (30) facing the radial wall (22). [7] Bearing seat (12) according to one of the preceding claims, characterized by that the undercut (24) has its greatest radial penetration depth (38) in the region of the connection region (32), which is arranged along the cross-sectional contour (26) of the undercut (24) on the side of the loading region (30) facing the radial wall (22). [8] Bearing seat (12) according to one of the preceding claims, characterized by in that the undercut (24) in the connection region (32), which is arranged along the cross-sectional contour (26) of the undercut (24) on the side of the loading region (30) facing the radial wall (22), has a radius (R1) of 0.8 millimeters, in the connection region (34), which is arranged along the cross-sectional contour (26) of the undercut (24) on the side of the loading region (30) facing the axial wall (18), has a radius (R2) of 0.9 millimeters, in the loading region (30) has a radius (R3) of at least 3 millimeters, has a radial penetration depth (38) of 0.8 millimeters and extends over a height (40) of 2.6 millimeters running in the axial direction (A). [9] Bearing seat (12) according to one of the preceding claims, characterized by that the bearing seat (12) is designed to support a motor vehicle shaft by means of the shaft bearing (14). [10] Motor vehicle with a bearing seat (12) according to one of the preceding claims.

Images