Structural unit, universal joint bearing and assembly method

Abstract

A structural unit (10) is proposed for assembly to a trunnion (18) of a universal joint bearing (20), the structural unit (10) comprising: a cup (12); a sealing ring (14) fixed to the cup; and a shield (16) connected to the cup when the structural unit is not assembled to the trunnion, wherein the cup comprises a bottom (22) and wherein the sealing ring comprises at least one sealing lip (24), the at least one sealing lip (24) pointing in a direction (26) having an axial component (28) directed towards the bottom.

Description

Technical Field

[0001] The present invention relates to a structural unit, a universal joint bearing and an assembling procedure. Background Art

[0002] Patent application DE 10 2018 207 056 A1 discloses a universal joint bearing comprising a cup, a sealing ring and a shield. The sealing ring and the shield are fixed to the cup in the fully assembled state. Summary of the Invention

[0003] In particular, the object of the present invention is to provide a universal joint bearing of increased efficiency. According to the invention, this object is achieved by the features of claim 1 and the features of claim 10, while advantageous embodiments and further developments of the invention can be derived from the dependent claims.

[0004] A structural unit for assembly to a trunnion of a universal joint bearing is proposed, comprising: a cup; a sealing ring secured to the cup; and a shield connected to the cup when the structural unit is not assembled to the trunnion, wherein the cup comprises a bottom, and the sealing ring comprises at least one sealing lip, the at least one sealing lip pointing in a direction having an axial component directed toward the bottom. Consequently, improved efficiency can be achieved. In particular, it can be achieved that the universal joint bearing can be assembled very cost-effectively using the structural unit, particularly since the structural unit can be secured to the trunnion by simply pushing the structural unit onto the universal joint bearing. Furthermore, it can be achieved, in particular, that grease initially contained in the universal joint bearing remains there by means of the sealing lip, thereby eliminating the need for re-greasing the universal joint bearing, which is a significant advantage over existing universal joint bearings.

[0005] Advantageously, the cup includes a region located at an axial end thereof and spaced apart from a central axis of the cup intersecting the base, the region being spaced apart from the central axis by the same distance as the region of the shield. This facilitates assembly of the universal joint bearing. In particular, it is easy to apply axial force from the cup to the sheet.

[0006] Furthermore, a universal joint bearing comprising the structural unit is proposed.

[0007] Preferably, the shield is fixed directly to the trunnion of the universal joint bearing, whereby only a small number of assembly steps are required.

[0008] Advantageously, the sealing ring comprises exactly one metal ring and / or exactly one elastic ring (or elastomeric ring). This allows for a simple and effective design. Furthermore, it is proposed that the elastic ring surrounds one or both ends of the metal ring in axial cross-section. This allows for a very reliable seal of the universal joint bearing. Furthermore, a simple method of securing the shield to the cup is achieved.

[0009] Advantageously, the elastic ring of the sealing ring contacts the shield at its radial inner surface and / or contacts the shield at the surface of a portion of the shield extending mainly radially in an axial section, thereby achieving early interception of intruding dust.

[0010] Preferably, the sealing ring comprises a metal ring having a substantially S-shape in axial cross-section, wherein the shape of the metal ring in the axial cross-section is constructed from two end branches and a middle branch, and at least one of the two end branches includes a distal end that curves parallel to the middle branch toward the other end branch. This ensures that the elastic portion of the sealing ring is securely fixed to the metal ring of the sealing ring.

[0011] In a preferred embodiment of the present invention, the first sealing lip of the sealing ring contacts the radially outer surface of the trunnion, which is in a region that is a straight extension of the raceway of the rolling elements of the universal joint bearing. Alternatively, the first sealing lip of the sealing ring is at a maximum distance of 0.8 mm from the radially outer surface of the trunnion, which is in a region that is a straight extension of the raceway of the rolling elements of the universal joint bearing. This configuration saves construction space in the axial direction, particularly with respect to the step between the raceway and the radially outer surface of the trunnion.

[0012] Preferably, the shield is substantially S-shaped in axial cross-section.

[0013] In a preferred embodiment of the present invention, the universal joint bearing comprises a (leaf) spring, which contacts the front surface of the eyelet and the rolling elements of the universal joint bearing.

[0014] Preferably, the first sealing lip of the universal joint bearing contacts the first radial outer surface of the trunnion, or the maximum distance from the first radial outer surface of the trunnion is 1 mm, preferably 0.8 mm, and the second sealing lip of the universal joint bearing contacts the second radial outer surface of the trunnion, and there is at least one step of the trunnion between the first radial outer surface and the second radial outer surface.

[0015] Advantageously, there is at least one step of the trunnion between the contact area of ​​the shield and the trunnion and the contact area of ​​the sealing lip of the universal joint bearing contacting the trunnion close to the shield.

[0016] Furthermore, a method for assembling a universal joint bearing, in particular a universal joint bearing as described above, is proposed, during which a structural unit is pressed onto the trunnion of the universal joint bearing, the structural unit comprising a cup, a sealing ring fixed to the cup, and a shield connected to the cup when the structural unit is not assembled onto the trunnion, wherein the cup comprises a bottom, the sealing ring comprises at least one sealing lip, the at least one sealing lip pointing in a direction having an axial component directed toward the bottom. This allows for increased efficiency, in particular with regard to assembling the universal joint bearing.

[0017] Further advantages are apparent from the following description of the drawings. The drawings illustrate embodiments of the present invention. The drawings, the description, and the claims contain many combined features. A person skilled in the art will also readily consider individual features and combine them into other meaningful combinations. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 shows a motor vehicle comprising a universal joint ( / cardan joint) having a universal joint bearing according to the invention,

[0019] Figure 2 The universal joint is shown in exploded view,

[0020] Figure 3 shows an axial section of a structural unit of a universal joint bearing according to the invention,

[0021] Figure 4 shows an axial section through the region of a universal joint bearing with a portion of a structural unit and a portion of a trunnion,

[0022] Figure 5 An axial section through an alternative embodiment of the structural unit according to the invention assembled on a trunnion is shown.

[0023] Description of Reference Numerals

[0024] 10 structural units

[0025] 12 cups ( / circle)

[0026] 14 Sealing ring

[0027] 16 shielding parts

[0028] 18 trunnion

[0029] 20 Universal joint bearing

[0030] 22 bottom

[0031] 24 Sealing lip

[0032] 26 Directions

[0033] 28 Axial component

[0034] 29 radial component

[0035] 30 areas

[0036] 32 end

[0037] 34 Central Axis

[0038] 36 areas

[0039] 38 Metal Ring

[0040] 40 elastic ring

[0041] 42 end

[0042] 44 end

[0043] 46 Surface

[0044] 48 Surface

[0045] 50 branches

[0046] 52 branches

[0047] 54 branches

[0048] 56 End

[0049] 60 Surface

[0050] 62 Roller

[0051] 64 rolling elements

[0052] 66 Sealing lip

[0053] 68 Sealing lip

[0054] 70 Surface

[0055] 72 leaf spring

[0056] 74 laps

[0057] 76 Space

[0058] 78 Space

[0059] 80 Space

[0060] 140 outer ring

[0061] 340 drive shaft

[0062] 360 Motor Vehicles

[0063] 400 Universal Joint

[0064] 540 Cross Piece DETAILED DESCRIPTION

[0065] Figure 1 A motor vehicle 360 ​​is shown, comprising a universal joint 400 having a universal joint bearing 20 according to the invention and a crosspiece 540 of the universal joint ( Figure 2 ). The motor vehicle is a truck. The universal joint is connected to the propeller shaft 340 of the truck. The trunnion 18 of the cross piece serves as the inner ring for the universal joint bearing. In addition, the universal joint bearing includes a cup 12, which serves as the outer ring 140 of the universal joint bearing. The universal joint bearing has a sealing ring 14 ( Figure 3 and Figure 4 ), the gap between the sealing cup and the trunnion of the sealing ring 14. The universal joint bearing and the sealing ring do not have a coil spring.

[0066] Figure 3 An axial section through a structural unit 10 according to the invention is shown. The structural unit 10 is part of a universal joint bearing 20 in the fully assembled condition. Figure 3 The structural unit 10 is shown without being assembled to the trunnion 18. The structural unit 10 comprises a cup 12 and a sealing ring 14 secured to the cup 12. More specifically, the metal ring 38 of the sealing ring 14 is frictionally locked to the radially inner surface of the cup 12. When the structural unit 10 is not assembled to the trunnion 18, the shield 16 of the structural unit is indirectly connected to the cup 12. Furthermore, the sealing ring 14 comprises an elastic ring 40. The universal joint bearing 20 comprises only one sealing ring, namely the sealing ring 14. The sealing ring 14 comprises a metal ring 38 and an elastic ring 40.

[0067] The elastic ring 40 includes a sealing lip 24 pointing in the direction 26 ( Figure 3). Direction 26 has an axial component 28 and a radial component 29. Axial component 28 points toward bottom 22 of cup 12. When the structural unit is assembled to trunnion 18, this means that grease located inside the bearing and moving from the rolling elements 64 of the universal joint bearing toward sealing lip 24 presses against sealing lip 24, and the sealing effect of sealing lip 24 is enhanced by this pressing. Due to this enhancement, grease cannot pass through sealing lip 24 and cannot reach the outside of the universal joint bearing.

[0068] In addition, the cup 12 includes a central axis 34 that intersects the bottom 22. The cup includes a region 30 ( Figure 3 ), the distance that region 30 is spaced away from central axis 34 is equal to the distance that region 30 is spaced away from region 36 of the shield (or guard) from central axis 34. When structural unit 10 is assembled onto trunnion 18, the shield is easily secured directly onto the trunnion by applying an axial force to the shield via cup 12, thereby pushing the shield onto the trunnion. When the shield is pushed onto trunnion 18, shield 16 is frictionally locked to trunnion 18.

[0069] The elastic ring 40 is molded onto the metal ring 38. In the illustrated construction, more specifically, the elastic ring 40 is compression molded onto the metal ring 38. The elastic ring 40 surrounds the first end 42 and the second end 44 of the metal ring 38, particularly when viewed in axial section. The sealing ring includes a metal ring that is substantially S-shaped in axial section ( Figure 4 ), and the shape of the metal ring in axial section is constructed by two end branches (limbs) 50, 52 and an intermediate branch 54. The end branch 52 includes a tip 56 that is bent toward the other end branch 50 in parallel with the intermediate branch.

[0070] Furthermore, elastic ring 40 includes a second sealing lip 66 that abuts against another radially outer surface of the trunnion. A step in the trunnion is located between this other radially outer surface and surface 60, such that this other radially outer surface is farther from central axis 34 than surface 60. Sealing lip 24 abuts against surface 60. In other embodiments of the present invention, sealing lip 24 does not contact surface 60 but is instead spaced a maximum distance of 0.8 mm from surface 60.

[0071] The radially outer surface 60 of the trunnion is in the region of a straight extension of the raceway 62 of the trunnion for the rolling elements 64 of the universal joint bearing. The shield 16 is frictionally locked against a radially outer surface 70 of the trunnion 18. Between the surface 70 and the aforementioned further radially outer surface against which the sealing lip 66 bears, there is a further step of the trunnion, which means that the surface 70 is located further from the center axis 34 than the further radially outer surface.

[0072] The elastic ring 40 of the sealing ring contacts the shield at its radial inner surface 46. As a result, the shield is frictionally locked to the sealing ring and thus to the cup 12, and also causes a sealing effect between the cup 12 and the shield 16. The other sealing lip 68 of the elastic ring 40 points mainly in the axial direction and bears against the surface 48 of the portion of the shield that extends radially in axial section and in the circumferential direction.

[0073] The leaf spring 72 of the structural unit 10 is located between the sealing ring 14 and the rolling element 64 and bears against both. More specifically, the leaf spring contacts the branch 52 of the metal ring. In an alternative embodiment of the present invention, a portion of the elastic ring 40 is located between the branch 52 and the leaf spring. This portion can have a thickness of up to 1 mm. Because the leaf spring directly contacts the branch 52, or, in other embodiments, the portion has only a small thickness, the pressure of the leaf spring against the rolling element 64 is very precisely defined, resulting in less tilting of the rolling element 64 and, thus, a longer service life and better performance.

[0074] The sealing lips 66, 68 have a different orientation than the sealing lip 24, which means that they are not aimed at preventing grease from the universal joint bearing from leaking to the outside. Instead, they are oriented so that their purpose is to prevent environmental contaminants and dust from intruding into the bearing from the outside. The shield provides a very strong first barrier to prevent larger contaminants (such as large particles, stones, sand, rocks, etc.) and accidental damage. The maximum outer diameter of the shield is smaller than the maximum outer diameter of the cup, which facilitates the assembly of the universal joint.

[0075] Since the universal joint bearing comprises only one sealing ring, the axial length of the sealing ring inside the cup is small, in particular compared to other universal joint bearings. As a result, the overall length of the universal joint bearing is reduced, so that the mass of the universal joint bearing is also reduced, or, by maintaining the same original length of the universal joint bearing as known from the prior art, the rolling elements 64 can be made larger than the rolling elements known from the prior art, thereby increasing the load capacity of the universal joint bearing.

[0076] The elastic ring 40 is made of rubber or thermoplastic material, etc. The shielding member can be made of metal or polymer.

[0077] In other embodiments of the present invention, the elastic ring 40 includes one or more holes for deaeration leading from the space 76 where the leaf spring 72 is located to the space 78 between the sealing lip 66 and the sealing lip 24. Alternatively or additionally, the elastic ring 40 may include one or more holes for deaeration leading from the space 76 to the space 80 between the sealing lip 66 and the sealing lip 68.

[0078] Figure 5 An alternative embodiment is shown in FIG. Components, features, and functions that are substantially the same are always given the same reference numerals. However, to distinguish between exemplary embodiments, the letter "a" is added to the Figure 5 The following description is mainly limited to the following exemplary embodiments. Figures 1 to 4 The differences between the exemplary embodiments of the present invention and the exemplary embodiments of the present invention, wherein the same components, features and functions are maintained, can be referred to. Figures 1 to 4 Description of exemplary embodiments in .

[0079] Similar to Figure 4 , Figure 5 An axial section through a structural unit 10 a according to the invention is shown, which has been assembled on a trunnion 18 a , thereby constructing a universal joint bearing. Figure 5 The universal joint bearing shown in Figures 1 to 4 The only difference from the universal joint bearing shown in FIG is that a plastic ring 74a is interposed between shield 16a and cup 12a. When using a universal joint bearing, movement between the cup and shield is possible, and plastic ring 74a prevents the shield from contacting the cup during such movement. Thus, plastic ring 74a functions as a sliding bearing element. In other embodiments of the present invention, plastic ring 74a can be a coated metal or soft metal.

Claims

1. A structural unit (10) for assembly onto a trunnion (18) of a universal joint bearing (20), comprising: Cup (12); a sealing ring (14) fixed to the cup; a metal ring disposed on the sealing ring and having a first end; a shield (16) connected to the cup in a state where the structural unit is not assembled to the trunnion, wherein the cup comprises a bottom (22) and, on opposite axial cup sides, axial portions extending in radial direction, wherein the sealing ring comprises a first end and at least one sealing lip (24), the at least one sealing lip (24) pointing in a direction (26) having an axial component (28) directed towards the bottom, The first end of the eyelet and the radially extending axial portion of the cup abut a first side of a portion of the sealing ring, and the shield abuts a second side of the portion of the sealing ring opposite the first side.

2. The structural unit according to claim 1, characterized in that The cup includes a region (30) located at an axial end (32) of the cup and spaced from a central axis (34) of the cup intersecting the bottom, the region (30) being spaced from the central axis (34) by the same distance as a region (36) of the shield is spaced from the central axis (34).

3. A universal joint bearing comprising the structural unit according to claim 1 or 2.

4. The universal joint bearing according to claim 3, characterized in that: The shielding member is directly fixed to the trunnion of the universal joint bearing.

5. The universal joint bearing according to claim 3 or 4, characterized in that: The sealing ring comprises precisely one elastic ring (40).

6. The universal joint bearing according to claim 5, characterized in that: In the axial section, the elastic ring surrounds one end or both end portions (42, 44) of the metal ring.

7. The universal joint bearing according to claim 3 or 4, characterized in that: The elastic ring of the sealing ring contacts the shield at a radially inner surface (46) of the shield and / or contacts the shield at a surface (48) of a portion of the shield extending mainly radially in an axial section.

8. The universal joint bearing according to claim 3 or 4, characterized in that: The sealing ring comprises the metal ring which is substantially S-shaped in axial section, the shape of the metal ring in the axial section being constructed by two end branches (50, 52) and a middle branch (54), and at least one of the two end branches comprises a terminal end (56) bent parallel to the middle branch toward the other end branch.

9. The universal joint bearing according to claim 3 or 4, characterized in that: The first sealing lip (24) of the sealing ring contacts the radial outer surface (60) of the ear shaft in the area of ​​the straight extension of the raceway (62) of the rolling element (64) for the universal joint bearing of the ear shaft (18), or the maximum distance between the first sealing lip (24) of the sealing ring and the radial outer surface (60) of the ear shaft in the area of ​​the straight extension of the raceway (62) of the rolling element (64) for the universal joint bearing of the ear shaft is 1 mm.

10. The universal joint bearing according to claim 3 or 4, characterized in that: The maximum distance of the first sealing lip (24) of the sealing ring from the radially outer surface (60) of the trunnion in the region of the straight extension of the raceway (62) of the trunnion for the rolling elements (64) of the universal joint bearing is 0.8 mm.

11. An assembly method for a universal joint bearing according to any one of claims 3 to 10, during which a structural unit is pushed onto a trunnion of the universal joint bearing, the structural unit comprising a cup, a sealing ring fixed to the cup, and a shield connected to the cup when the structural unit is not assembled to the trunnion, wherein: The cup comprises a bottom, and the sealing ring comprises at least one sealing lip pointing in a direction having an axial component towards the bottom.

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