CN111433473A

CN111433473A - Rolling bearing with integrated pressure seal

Info

Publication number: CN111433473A
Application number: CN201880077397.0A
Authority: CN
Inventors: 本杰明·鲁丁
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2017-12-06
Filing date: 2018-11-28
Publication date: 2020-07-17
Anticipated expiration: 2038-11-28
Also published as: DE102017128937A1; DE102017128937B4; WO2019110045A1; CN111433473B

Abstract

The invention relates to a rolling bearing (1) having an inner ring (9) and an outer ring (2), wherein rolling bodies (3) are arranged between the inner ring (9) and the outer ring (2). Furthermore, an annular disk (4) is arranged between the outer ring (2) and the inner ring (9), at least on the pressure side. It is proposed that the annular disk (4) is received in a form-fitting manner in a recess (15) of the outer ring (2) or of the inner ring (9), and that a shoulder (16) is formed on the annular disk (4), on which shoulder a sealing ring (5) is mounted.

Description

Rolling bearing with integrated pressure seal

Technical Field

The invention relates to a rolling bearing with an integrated pressure seal according to the preamble of the independent claim.

Background

In order to seal the pressure in the dual clutch transmission, a plastic ring made of polyamideimide is inserted. The plastic ring is embodied as a slotted ring in the form of a piston ring and can be inserted into the groove by corresponding rotation, the plastic ring snapping into the groove after the tension for stretching the ring is removed. Via this polyamideimide ring, it is possible to seal with low leakage up to operating pressures of 6bar oil pressure. Such a plastic ring can be inserted into a groove of the dual clutch transmission at a suitable point and is arranged upstream of the rolling bearing. The rolling bearing has a sealing disk. The oil pressure presses the plastic ring in the axial direction onto the side of the groove in which the plastic ring is accommodated, thereby activating the sealing action of the plastic ring. The rolling bearing is thus not exposed to high operating pressures, so that the rolling bearing can be sealed in a simple manner or, if appropriate, can be completely relieved of sealing.

From DE 102009006649 a1 a dual clutch transmission is known, in which the transmission shaft is rotatably mounted by means of a rolling bearing. In this case, a plastic sealing ring is provided upstream of the rolling bearing in order to reduce the oil pressure acting on the rolling bearing.

However, the known solutions are disadvantageous: the plastic sealing ring arranged upstream of the roller bearing requires additional installation space. Furthermore, at least one additional groove is required to lock the plastic sealing ring, which requires additional machining of the components on the pressure side, in particular in a dual clutch transmission.

Disclosure of Invention

The object of the present invention is to provide a rolling bearing with an integrated pressure seal, which, with a compact and inexpensive embodiment, also achieves a seal with significantly increased operating pressures in relation to the environment.

This object is achieved according to the invention by a rolling bearing having an inner ring and an outer ring, wherein a plurality of rolling bodies are arranged between the inner ring and the outer ring, and wherein an annular disk is arranged between the outer ring and the inner ring, at least on the pressure side. The annular disk is received in a form-fitting and/or force-fitting manner in a recess of the outer ring or of the inner ring, wherein a shoulder is formed on the annular disk, on which shoulder a sealing ring is mounted. In this way, the sealing ring which is movable in a limited manner in the axial direction is integrated in the rolling bearing, so that a relatively high sealing effect is achieved. In this case, the sealing ring is displaced on the pressure side of the rolling bearing, i.e. on the side where the higher operating pressure is present, when the pressure increases, so that the sealing ring is pressed against the contact surface and the sealing gap can be closed. Since the sealing ring is activated by the operating pressure of the operating fluid, in particular oil, on the pressure side and since the sealing ring is pressed against the contact surface in this connection, an operating pressure of 2bar or more, which is increased relative to the ambient pressure, can be sealed off, which operating pressure cannot be sealed off at the rolling bearing by means of the known sealing lips and leads to leakage. Due to the axial movability, the sealing ring is again separated from the contact surface when the operating pressure on the pressure side drops, so that a negative pressure in the region of the rolling bodies and a resulting reduced lubrication of the rolling bodies are avoided.

The rolling bearing specified in the independent claim can be advantageously improved and improved by the features listed in the dependent claims.

In a preferred embodiment of the invention, it is provided that: on the side of the annular disk facing the rolling bodies, a bevel is provided, which ends at the shoulder. The bevel on the annular disk simplifies the installation of the sealing ring and reduces the risk of damage to the sealing ring during installation.

In a further development of the invention, it is proposed that: a shoulder is formed on the inner ring of the rolling bearing. By means of this shoulder, the hydraulic activation of the sealing ring can be improved when the pressure increases on the pressure side of the rolling bearing. The sealing ring thereby flows at an advantageous angle and on an advantageous side, so that the sealing ring can be activated more easily, i.e. pressed in the axial direction against the stop surface.

In this case, it is preferred that a sealing gap is formed between the annular disk and the inner ring, wherein the sealing gap extends in a first section parallel to the bearing surface of the inner ring and in a second section at an angle α relative to the first section, it being possible for larger particles to enter the rolling bearing and damage the sealing ring or to cause seizure of the sealing ring, so that the sealing ring can no longer be activated hydraulically, it being possible for the sealing ring to be acted upon axially particularly advantageously by a sealing gap extending in a first section parallel to the bearing surface of the inner ring and in a second section at an angle relative to the first section, it being avoided here that deposits entering the sealing gap are deposited on the sealing surfaces and can adversely affect the sealing effect of the sealing ring.

In this case, it is particularly preferred if a chamfer is formed on the sealing ring on its side facing the shoulder. The seal medium can be deflected into the groove by means of a bevel on the side of the sealing ring facing the shoulder of the inner ring, whereby the sealing ring can be activated particularly simply hydraulically. Furthermore, dirt entering the rolling bearing through the sealing gap can deposit in the groove, so that it is kept away from the hydraulically sealed face and deposits on the groove bottom.

In a preferred embodiment of the invention, it is proposed that the chamfer has an angle β in the range from 10 ° to 45 °, preferably between 20 ° and 40 °, that the sealing ring is activated by the chamfer having an angle of 10 ° to 45 °, as far as possible with the oil flow which is conducted onto the sealing ring through the sealing gap, such that the sealing ring moves axially on the contact surface of the inner ring and seals the second sealing gap, the inner diameter of the sealing ring here preferably being in the range of ± 1mm of the shoulder diameter of the shoulder on the inner ring, and optimum activation of the sealing ring can thus be achieved.

In an advantageous embodiment of the invention, it is provided that: a groove for releasing the sealing ring is formed on the inner ring. Sufficient space can be provided in the radial direction by corresponding grooves on the inner ring, so that the sealing ring can be moved in the axial direction without contact with the inner ring and can be activated and deactivated. On the other hand, this provides a space in which dirt entering the sealing gap can be deposited without pressing against the sealing ring and thus without causing increased wear on the sealing ring.

According to a preferred embodiment of the invention, a stop surface is formed on the inner ring, wherein a second sealing gap is formed between the sealing ring and the stop surface of the inner ring. The axial stop for the sealing ring can be formed in a simple and cost-effective manner by a stop surface integrated into the inner ring. Furthermore, with the second sealing gap, if the second sealing gap is open when the sealing ring is not in contact with the stop, a flow of lubricant into the region of the rolling bodies is achieved again, so that the risk of negative pressure in the bearing is eliminated and the risk of a reduction in the supply of lubricating substance associated therewith is eliminated.

In a preferred embodiment of the invention, it is provided that: the sealing ring is made of a plastic material resistant to high temperatures, chemicals and wear, preferably a polyamideimide material. Polyamideimides are characterized by high thermal stability up to over 200 ℃ and high resistance to chemicals and abrasion resistance relative to other plastics. The polyamide imide ring is therefore particularly suitable as a sealing ring in the rolling bearing according to the invention, since even in the case of axial displaceability, unlike the case in which the sealing ring is composed of an elastomer, no increased wear and thus a correspondingly high fatigue strength can be expected. Furthermore, the closed sealing ring can be produced in an injection molding process from polyamideimide in a cost-effective manner.

In an advantageous further development of the rolling bearing, it is proposed that: the shoulder of the annular disk and the groove on the inner ring are each wider than the sealing ring, so that the sealing ring can be moved in the axial direction between the corresponding stop surfaces on the inner ring and on the annular disk. The sealing ring can be easily activated and deactivated by the limitation of the axial mobility of the sealing ring on the annular disk and on the inner ring. It is ensured here that: the sealing ring does not tilt or become lost, because the width of the groove and the width of the stop face, respectively, are only slightly wider than the width of the sealing ring.

The different embodiments of the invention mentioned in the present application can advantageously be combined with one another, as long as no further explanations are made in individual cases.

Drawings

The invention is explained in detail below on the basis of preferred embodiments and the accompanying drawings. It shows that:

fig. 1 shows an embodiment of a rolling bearing according to the invention with an integrated pressure seal in a sectional view.

Detailed Description

Fig. 1 shows an exemplary embodiment of a rolling bearing 1 according to the invention with an integrated pressure seal. The rolling bearing 1 according to the invention comprises an outer ring 2 and an inner ring 9 and rolling bodies 3 arranged between the outer ring 2 and the inner ring 9. Furthermore, the rolling bearing 1 according to the invention comprises an annular disk 4 which is fixed to the outer ring 2 and which is arranged between the inner ring 9 and the outer ring 2 on the pressure side and which closes the rolling bearing 1 on the pressure side, with the exception of a sealing gap 12. The annular disk 4 is preferably pressed into the outer ring 2, wherein a shoulder 15 is provided on the outer ring 2, which shoulder acts as a stop for the annular disk 4 during the pressing-in. The annular disk 4 has a bevel 8 on its side facing the rolling bodies 3 in order to achieve a damage-free mounting of the sealing ring 5, in particular of the polyamide-imide material, on the shoulder 16 of the annular disk 4. The rolling bearing 1 is preferably designed as a ball bearing, but other types of rolling bodies 3 are also possible.

The inner ring 2 has, on its end facing the pressure side, a shoulder 7 which separates the sealing gap 12 from the groove 10 on the inner ring 9, the sealing ring 5 has, on its side facing the shoulder 7, a ramp 19 which has an angle β of 0 ° to 45 °, preferably an angle β of 20 ° to 40 °, by means of which the oil pressure p of the oil 6 which is pressed from the pressure side into the rolling bearing 1 is guided via the sealing gap 12 onto the ramp 19 of the sealing ring 5, so that the sealing ring 5 is correspondingly activated and axially pressed against the stop face 18 on the inner ring 9, as a result of which the sealing gap 13 between the sealing ring 5 and the inner ring 9 is closed, so that the region of the rolling elements 3 is sealed off from the oil pressure p on the pressure side of the rolling bearing 1, the sealing space 11 which is delimited by the shoulder 7, the groove 10, the sealing ring 5 and the annular disk 4 is enlarged by moving the sealing ring 5, the sealing gap 12 has a first portion 12a ° and a second portion 12b which extends parallel to the bearing face 17 of the inner ring 9, the second portion being angled at an angle 5 α ° to an angle of approximately 10 ° to 3936 ° to α.

A stop surface 20 is formed on the annular disk 4, which limits the axial movement of the closed sealing ring 5 to the pressure side. Diameter D of the sealing ring 5_DPreferably at the shoulder diameter D_SWithin ± 1mm, and thus an optimal activation of the sealing ring 5 can be achieved. The groove 10 has a groove base 14 with a diameter D_NThe bottom of the groove is located below the shoulder 7. The groove base 14 is preferably located 1mm to 5mm below the shoulder 7, so that there is sufficient space in the radial direction for the sealing ring 5 and the movement of the sealing ring 5.

In a simplified embodiment of the invention, the angle α between the shoulder 7 and the bearing surface 17 of the inner ring 9 and the angle β at the sealing ring are selected to be equal to 0 °, in which simplified embodiment the sealing ring therefore has a rectangular cross section and the shoulder 7 coincides with the groove bottom 14 of the groove 10.

If the oil pressure p of the oil 6 on the pressure side of the rolling bearing 1 according to the invention increases, this oil pressure p is suppressed by the seal gap 12. Furthermore, the sealing gap 12 prevents large particles from entering the rolling bearing 1, which could damage the sealing ring 5. The oil pressure p displaces the sealing ring 5 in the axial direction towards the stop surface 18 on the inner ring 9, whereby the second sealing gap 13 between the sealing ring 5 and the inner ring 9 is closed. By means of the oil pressure p, the sealing ring 5 is pressed against the stop face 18, whereby also intermediate pressures, in particular oil pressures p in the range of 2bar to 12bar, can be sealed. This oil pressure p cannot be directly sealed in the rolling bearing 1 for simple sealing elements known from the prior art, but requires a seal arranged upstream of the rolling bearing 1.

In conclusion, it can be determined that: the proposed rolling bearing with an integrated pressure seal enables an embodiment that also enables a seal with a significantly increased operating pressure relative to the environment with a compact and low-cost embodiment.

List of reference numerals

1 rolling bearing

2 outer ring

3 rolling element

4 annular disc

5 sealing ring

6 oil

7 shoulder part

8 bevel edge

9 inner ring

10 groove

11 sealed chamber

12 first seal gap

13 second seal gap

14 groove bottom

15 recess

16 convex shoulder

17 bearing surface

18 stop surface

19 inclined plane

20 stop surface

α angle on inner ring

β angle on sealing ring

D_DDiameter of sealing ring

D_NDiameter of groove bottom

D_SDiameter of shoulder

p oil pressure

Claims

1. Rolling bearing (1) having an inner ring (9) and an outer ring (2), wherein rolling bodies (3) are arranged between the inner ring (9) and the outer ring (2), and wherein an annular disc (4) is arranged between the outer ring (2) and the inner ring (9) at least on the pressure side,

characterized in that the annular disk (4) is received in a recess (15) of the outer ring (2) or of the inner ring (9), and a shoulder (16) is formed on the annular disk (4), on which shoulder a sealing ring (5) is mounted.

2. Rolling bearing (1) according to claim 1,

a bevel (8) is provided on the side of the annular disk (4) facing the rolling bodies (3), said bevel ending on the shoulder (16).

3. Rolling bearing (1) according to claim 1 or 2,

a shoulder (7) is formed on an inner ring (9) of the rolling bearing (1).

4. Rolling bearing (1) according to claim 3,

a sealing gap (12) is formed between the annular disk (4) and the inner ring (9), wherein the sealing gap (12) extends in a first section (12a) parallel to a bearing surface (17) of the inner ring (9) and in a second section (12b) at an angle α relative to the first section (12 a).

5. Rolling bearing (1) according to claim 3 or 4,

a bevel (19) is formed on the sealing ring (5) on its side facing the shoulder (7).

6. Rolling bearing (1) according to claim 5,

the ramp (19) has an angle β of 10 ° to 45 °.

7. Rolling bearing (1) according to any of claims 1 to 6,

a groove (10) for releasing the sealing ring (5) is formed on the inner ring (9).

8. Rolling bearing (1) according to any of claims 1 to 7,

a stop surface (18) is formed on the inner ring (9), wherein a second sealing gap (13) is formed between the sealing ring (5) and the stop surface (18) of the inner ring (9).

9. Rolling bearing (1) according to any of claims 1 to 8,

the seal ring is made of a polyamideimide material.

10. Rolling bearing (1) according to any of claims 1 to 9,

the shoulder (16) of the annular disk (4) and the groove (10) on the inner ring (9) are each wider than the sealing ring (5) such that the sealing ring (5) can be moved in the axial direction between corresponding stop surfaces (18, 20) on the inner ring (9) and on the annular disk (4).