Axial bearing with limited rotational movement and centring
Patent Information
- Application Number
- PCT/EP2025/089146
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-03-28
- Filing Date
- 2025-12-30
- Publication Date
- 2026-10-01
Smart Images
Figure EP2025089146_01102026_PF_FP_ABST
Abstract
Description
[0001] R.418342
[0002] - 1 -
[0003] Description
[0004] Title:
[0005] The present invention relates to an axial bearing for transmitting axial forces.
[0006] State of the art
[0007] An axial bearing is a special type of bearing designed to transmit axial forces, i.e., forces acting along the bearing's axis. Unlike radial bearings, which primarily handle radial forces, axial bearings are designed to absorb forces acting along the axis. They are frequently used in machines and equipment where such forces occur, such as gearboxes, pumps, or vehicle axles. There are various types of axial bearings, including axial ball bearings, axial roller bearings, and axial cylindrical roller bearings, which are selected according to the load and application. These bearings are characterized by their ability to handle high axial loads in compact designs. They can also be used in conjunction with radial bearings in many applications to simultaneously transmit both radial and axial forces.
[0008] WO 2009 / 074413 A2 describes a thrust bearing designed as a clutch release bearing for a clutch assembly. It consists of two flat bearing races arranged radially offset and containing rolling elements positioned in an overlap area. The bearing races are made of sheet metal and can be manufactured by forming processes, which reduces costs and increases service life. Furthermore, the races undergo heat treatment to minimize distortion. A guide for radially guiding the cage assembly is also provided. R.418342
[0009] - 2 -
[0010] The object underlying the invention is to provide an axial bearing for transmitting axial forces which transmits forces only in the axial direction.
[0011] The problem is solved by an axial bearing according to claim 1. Preferred embodiments can be found in the dependent claims.
[0012] Disclosure of the invention
[0013] The invention provides an axial bearing for transmitting axial forces. The axial bearing comprises a first bearing disk, on which a first axial annular rib is formed on the outer circumference, a second bearing disk, on which a second axial annular rib is formed on the outer circumference, wherein the first and second axial annular ribs are designed to overlap, forming a radial gap, and balls that are accommodated between a space defined by the first and second bearing disks. At least three circumferentially uniformly distributed positive locking elements are formed on the first and second annular ribs, which interact in such a way that a limited rotational movement between the first and second bearing disks is permitted. Elastic return elements are arranged between the first and second annular ribs, by means of which the first and second bearing disks can be centered relative to each other after radial displacement.
[0014] According to the invention, an axial ring web is understood to be a web that extends in the axial direction of the thrust bearing. Both ring webs are aligned in opposite axial directions, so that the installation space is formed between the two bearing discs. The positive locking elements are arranged in the area of the ring webs. Although the positive locking elements limit rotational movement, sufficient clearance is provided in the positive locking elements to allow limited rotational movement. The amount of rotational movement can, for example, be limited to a maximum of 60°. By using balls between the bearing discs R.418342
[0015] - 3 -
[0016] Rotation of the bearing discs is possible with low friction. This allows the axial bearing to compensate for any twisting without force.
[0017] In addition to rotation, radial movement is also possible through the gap between the ring lands. In other words, the bearing discs can shift relative to each other to a limited extent. This shift is also facilitated by the balls. Furthermore, this shift is not limited by the positive locking elements, which only act on rotational movement. Therefore, radial shifting is possible even without force. After the shift, the bearing discs can be re-centered by the elastic return elements acting on both ring lands. This makes it possible to use axial bearings for force measurements where only axial forces are to be measured.
[0018] Positioning-related movements in other directions are compensated for by the axial bearing, so that no forces are introduced as a result.
[0019] In a preferred embodiment of the invention, each positive locking element is formed by an elongated slot extending circumferentially on the ring web, which interacts with a pin attached to the opposite ring web. The elongated slot thus extends circumferentially. The permissible amount of rotational movement can be adjusted via the length of the elongated slot. The pin engages in the elongated slot, so that the pin interacts with the circumferential ends of the elongated slot to limit the rotational movement. A limited rotational movement is thus permitted in a simple manner by means of such a positive locking element.
[0020] In a further preferred embodiment of the invention, the return elements are held by the pins. By attaching the return elements to the pins, a separate fastening of the return elements between the two ring bars can be dispensed with. This allows such return elements to be arranged between the ring bars in a simple manner.
[0021] Preferably, the ring bridge to which the pin is attached has a blind hole formed around the pin in which the return element is received. R.418342
[0022] - 4 -
[0023] The blind hole thus has a larger diameter than the outer diameter of the pin. The pin is therefore secured to the bridge at the bottom of the blind hole. The diameter of the blind hole is dimensioned such that the return element can be accommodated within it. The blind hole thus increases the length of the return element between the ring bridges by the depth of the blind hole. Accordingly, a longer return element can be selected, resulting in improved return action.
[0024] In an alternative design, the ring bridge, on which the elongated hole is formed, additionally creates a blind hole in which the return element is received. This blind hole also increases the length of the return element by the depth of the hole. Furthermore, this design provides sufficient travel for the pin to perform a radial movement before it contacts the bottom of the blind hole.
[0025] Advantageously, the return element is a spring. Using a spring as a return element has the advantage of being economical and space-saving, allowing it to be arranged around the pin. Furthermore, unlike a rubber return element, a spring does not age.
[0026] In a further advantageous embodiment, the number of positive locking elements is selected according to the expected torque, so that a higher number of positive locking elements are provided for higher torques. With a higher expected torque, the shear force on the pins is also higher. To prevent this torque from causing the pins to shear off if they come into contact with the edges of the elongated holes, the number of pins is increased in such cases. By adjusting the number of positive locking elements to the expected torque, it can be ensured that the pins do not shear off. R.418342
[0027] - 5 -
[0028] In a practical design, the number of balls is selected according to the expected axial force, so that a higher axial force results in a greater number of balls arranged between the first and second bearing disks. By adjusting the number of balls to the expected axial force, damage or destruction of the axial bearing due to excessive axial force can be avoided. Such an adjustment also allows the weight of the axial bearing to be kept low by using fewer balls.
[0029] According to another practical design, the installation space is limited by flat surfaces. By using flat surfaces on which the balls can move, they can move freely in all radial directions, thus avoiding any restriction of such movement. Accordingly, radial movements can be compensated for without force by the axial bearing.
[0030] Preferably, a seal is arranged between the two bearing discs, sealing the installation space from the outside. Such a seal, which can be, for example, in the form of an O-ring seal, protects the installation space from dirt and moisture.
[0031] This prevents premature wear of the balls caused by dirt. Such a seal thus increases the service life of the axial bearing.
[0032] According to a particularly advantageous embodiment, the balls are held in a cage. A cage is understood to be a component that securely holds the balls in recesses provided within it. The balls are rotatably arranged in these recesses. Such a cage has the advantage of preventing the balls from colliding with each other and thus avoiding friction and relative movement. Furthermore, a cage can incorporate a lubrication reservoir for the balls, ensuring a continuous supply of lubricant. Consequently, such a cage can increase the service life of the thrust bearing.
[0033] Exemplary embodiments of the invention are shown in the drawing and explained in more detail in the following description. It shows: R.418342
[0034] - 6 -
[0035] Figure 1 Perspective view of an axial bearing according to a first embodiment of the invention,
[0036] Figure 2 Top view of the axial bearing according to Figure 1 ,
[0037] Figure 3 Sectional view of the axial bearing according to Figure 1 ,
[0038] Figure 4 Detail view of the positive locking elements of the embodiment from Figure 1,
[0039] Figure 5 Top view of an axial bearing according to a second embodiment of the invention,
[0040] Figure 6 Sectional view of the axial bearing according to Figure 5,
[0041] Figure 7 Top view of a bearing disk of a thrust bearing according to a third embodiment, and
[0042] Figure 8 sectional view of the axial bearing according to Figure 7 with second bearing disc.
[0043] Figure 1 shows a perspective view of a thrust bearing 10 according to a first embodiment of the invention. The thrust bearing 10 comprises a first bearing disk 14 and a second bearing disk 18, which are arranged opposite each other. In the embodiment shown, both bearing disks 14 and 18 are round. The first bearing disk 14 has a first axial annular rib 22, which is arranged on an outer circumference of the bearing disk 14. Similarly, the second bearing disk 18 has a second axial annular rib 26. Both annular ribs 22 and 26 extend in opposite axial directions.
[0044] The two bearing discs 14, 18 are arranged relative to each other such that the ring webs 22, 26 overlap, forming a radial gap 30. R.418342
[0045] - 7 -
[0046] Accordingly, the outer diameter of the second bearing disk 18 is larger than the outer diameter of the first bearing disk 14. A space 34 is formed between the two bearing disks 14, 18, in which a plurality of balls 38 are arranged. The axial bearing 10 additionally has five positive locking elements 42, which are arranged uniformly distributed in the circumferential direction on the first and second annular webs 22, 26.
[0047] The positive locking elements 42 are each formed by a pin 46, which is fastened in the first annular web 22 and interacts with an elongated hole 50 in the second web 26. As shown in Figure 2, the elongated hole 50 allows limited rotational movement between the first and second bearing disks 14, 18. Likewise, the gap 30 between the two annular webs 22, 26 allows limited movement in the radial direction. The radial direction corresponds to the X and Y directions of the axial bearing 10 shown in Figure 2.
[0048] Figure 3 shows a sectional view of the axial bearing 10 according to Figure 1. This figure again shows the gap 30 between the two ring webs 22, 26. This figure further shows that an elastic return element 54, designed as a spring, is arranged between the first and the second ring web 22, 26. This return element 54 is arranged around the pin 46 and, in the event of a radial displacement of the bearing disks 14, 18 relative to each other, causes them to center themselves again.
[0049] A detailed view of the pin 46 and the spring 54 is shown in Figure 4. This shows that the first ring 22, to which the pin 46 is attached, has a blind hole 58 around the pin 46. This blind hole 58 is shaped such that the spring 54 can be received in it. This blind hole 58 allows a longer spring 54 to be used between the first and second ring 22, 26, thus improving the centering of the two bearing discs 14, 18 relative to each other. Figure 4 also shows that the pins 46 have a slot 62 on their end face, through which they can be screwed in using, for example, a screwdriver. R.418342
[0050] - 8 -
[0051] Figure 5 shows a top view of a thrust bearing 10 according to a second embodiment of the invention. This thrust bearing 10 differs from the thrust bearing 10 in Figure 1 in that only three positive locking elements 42 are provided instead of five. Furthermore, the installation space 34 between the first and second bearing disks 14, 18 is completely filled with balls 38. This allows a higher axial load to be absorbed, in contrast to the embodiment shown in Figure 1.
[0052] A sectional view of the axial bearing 10 from Figure 5 is shown in Figure 6. The sectional view in Figure 6 differs from the sectional view in Figure 3 in that the pin 46 is not fastened in the first annular web 22, but in the second annular web 26 of the second bearing disk 18.
[0053] Accordingly, the elongated hole 50 is also formed in the first ring web 22. The elongated hole 50 is designed in the form of a blind hole 58, so that the spring 54 can engage in this blind hole 58. A longer spring 54 can also be used to center both bearing discs 14, 18 relative to each other.
[0054] A top view of a bearing disk 14 according to a third embodiment is shown in Figure 7. For clarity, the second bearing disk 18 has been omitted in this figure. Figure 7 differs from the arrangement in Figure 5 in that the balls 38 are not freely held in the installation space 34, but are provided in a cage 66, which is arranged in the installation space 34. Such a cage 66 prevents the balls 38 from rubbing against each other during radial movement. Accordingly, wear can be reduced.
[0055] Figure 7 additionally shows that a seal 70 is arranged on one end face of the first annular web 22. This seal 70 is shown even more clearly in the sectional view of Figure 8. In this figure, the second bearing disk 18 is shown again. Here it can be seen that the first annular web 22 has an end-face groove 74 in which the seal 70 is received. The seal 70 also rests against the second bearing disk 18, so that R.418342
[0056] - 9 -
[0057] The installation space 34, in which the spheres 38 are accommodated, is protected against external influences, such as dirt or moisture.
Claims
R.418342 - 10 - Claims 1. Axial bearing (10) for transmitting axial forces, comprising: a first bearing disk (14) on which a first axial ring web (22) is formed on the outer circumference, a second bearing disk (18) on which a second axial ring web (26) is formed on the outer circumference, wherein the first and second axial ring webs (22, 26) are designed such that they overlap, forming a radial gap (30), and Balls (38) which are received between a space (34) defined by the first and the second bearing disk (14, 18), characterized in that On the first and second annular web (22, 26) at least three circumferentially distributed positive locking elements (42) are formed, which interact in such a way that a limited rotational movement between the first and second bearing disk (14, 18) is permitted, wherein elastic restoring elements (54) are arranged between the first and second annular web (22, 26), via which the first and second bearing disk (14, 18) can be centered relative to each other after radial displacement.
2. Axial bearing (10) according to claim 1 , characterized in that each positive locking element (42) is formed by an elongated hole (50) formed in the circumferential direction on the ring web (22, 26), which interacts with a pin (46) attached to the opposite ring web (22, 26).
3. Axial bearing (10) according to claim 2, characterized in that the return elements (54) are held by the pins (46).
4. Axial bearing (10) according to one of claims 2 or 3, characterized in that the ring web (22, 26) to which the pin (46) is attached R.418342 - 11 - is a blind hole (58) formed around the pin (46) in which the return element (54) is received.
5. Axial bearing (10) according to one of claims 2 or 3, characterized in that the annular web (22, 26) on which the elongated hole (50) is formed additionally forms this as a blind hole (58) in which the return element (54) is received.
6. Axial bearing (10) according to one of the preceding claims, characterized in that the return element (54) is a spring.
7. Axial bearing (10) according to one of the preceding claims, characterized in that the number of positive locking elements (42) is selected according to the expected torque, so that a higher number of positive locking elements (42) are provided for higher torque.
8. Axial bearing (10) according to one of the preceding claims, characterized in that a number of balls (38) is selected according to the expected axial force, so that a higher number of balls (38) are arranged between the first and second bearing disk (14, 18) in the case of a higher axial force.
9. Axial bearing (10) according to one of the preceding claims, characterized in that the installation space (34) is limited by flat surfaces.
10. Axial bearing (10) according to one of the preceding claims, characterized in that a seal (70) is arranged between the two bearing discs (14, 18), via which the installation space (34) is sealed to the outside.
11. Axial bearing (10) according to one of the preceding claims, characterized in that the balls (38) are received in a cage (66).