KR20090013104U - Spring strut bearing - Google Patents

Abstract

The present invention relates to a spring strut bearing 13 comprising a bearing disc 14. The bearing disc 14 comprises a collar portion 15 which is oriented in the same direction with respect to the bearing axis 6 and protrudes from the bearing disc 14 itself, which collar portion 15 is the bearing disc. It is made of the material of 14 and formed integrally with its bearing disc.

Description

Spring Strut Bearing {SPRING STRUT BEARING}

The invention relates to a spring strut bearing comprising a bearing disc. According to the invention the bearing disc has a collar portion extending in the same direction with respect to the bearing axis and protruding from the bearing disc, which collar portion is made of the material of the bearing disc and integrally formed with the bearing disc.

Such spring strut bearings have been disclosed from DE 199 21 695 A1. Spring strut bearings usually include a lower bearing disk and an upper bearing disk. The upper bearing disc is supported at the chassis side. The lower bearing disc seats the spring strut bearing on the spring plate. Bearing discs are annular discs with holes in the center. The collar part is drawn out from the hole of the lower bearing disk. In this connection it is also conceivable that the collar is formed in the upper bearing disk. The lower bearing disc of the spring strut bearing according to DE 199 21 695 A1 has a collar, by means of which the spring strut bearing is centered on the central axis of the piston rod of the shock damper at the spring plate and transverse to the bearing axis. Is supported. The bearing axis and the center axis are located above and below each other. Depending on how it is substituted for this, the collar can be centered on another component.

In the spring strut bearing the elastic force is supported through the spring plate from the axial directions. The axial directions are directions opposite to each other and oriented in the same direction as the central axis of the piston rod of the impact damper. The spring strut bearing has an additional lateral force. This lateral force is a force acting in the radial direction. The radial directions in this case act perpendicular to the axial directions and are thus oriented perpendicular to each of the central axis and the bearing axis. The spring strut bearing is radially supported and guided in the bearing disc via the collar.

As can be seen from DE 199 21 695 A1, the collar is oriented in the axial direction from the bearing disc in the same direction as the bearing axis and protrudes downwards towards the impact damper direction or upwards towards the chassis direction as disclosed from JP 2005291232 A. Protrude in the direction.

Bearing discs are molded parts made of sheet steel, and are thus produced simply and economically. These bearing rings are punched and pressed from the sheet steel sheet or cold drawn. Usually the bearing discs have a raceway for the rolling body, and in alternative embodiments it may be a support disc for the sliding disc. The rolling body is a ball or a roller.

If the bearing disc has a raceway for the rolling body, the bearing disc at least hardens the raceway portion. Since the bearing discs are made of sheet steel, only the edge layer needs to be cured, not the whole.

In general, total hardening is considered to be essentially hardened and / or precipitate hardened throughout the structure in the workpiece to the core, so that in this case the bearing disc has a total thickness including the core extending from the edge layer. Cures over. Such hardened bearing discs may be sensitive to load based on the thickness of the sheet, and may break under load. Therefore, the bearing disc of thin plates usually hardens only the edge layer.

In edge layer curing, only one layer is cured from each surface of the bearing disk on both sides to a predetermined depth on the surface of the workpiece. The depth at this time is determined according to the sheet thickness. In contrast, the core is usually left uncured, whereby the disk remains elastic to some extent and can be adapted accordingly by elastic deformation even under load.

However, the load on the disc, in particular the lower bearing disc, is limited because the depth of cure from the edge layer hardening is limited. If too high a load is applied, for example, the rolling body penetrates into the hardened edge layer, which may damage the bearing.

It is an object of the present invention to provide such a spring strut bearing, which is simple and economical to produce the spring strut bearing of the type mentioned above, but which is also suitable for the increased load requirements in all situations.

This object is achieved by the features of claim 1 and two further independent claims.

The bearing disc is a molded part made of a circular disk blank, in which the collar part is formed integrally, that is to say a bearing disc and a single material. The collar portion is made of a material that is plastically deformed from the disc blank.

The degree of deformation applied to the shaping of the collar portion is greater than that of the bearing disk. The strain in the axially oriented collar is preferably at least twice higher than the strain in the bearing disc. The degree of deformation of the collar portion is relatively high compared to the degree of deformation of the disk, the value of which is at least 30%, preferably 50%. The collar part is produced, for example, by extrusion or cold forming similar to extrusion. The deformation of the bearing disc is about 10%. This degree of deformation is essentially determined by the plastically displaced material during the incidence processing of the raceway and by so-called axial runout. And by axial runout, after the forming elements such as the collar and the raceway have been provided, the bearing discs are arranged in such a way that the ring surfaces facing in the axial direction and in opposite directions are flat and parallel to each other. The bearing disc is again flattened.

Evaluation criteria for the degree of deformation in this case are the axial thickness of the disc blank measured at the edge of the hole of the disc blank, the radial wall thickness of the collar portion projecting from the disc, and the axial length of the collar portion.

The workpiece volume remains unchanged during deformation. But the geometry changes. The degree of deformation is a value for evaluating the change in the geometric structure occurring in the workpiece compared with the initial state of the blank used in the deformation process or the portion of the blank. Strain is calculated as the natural logarithm of the ratio of the modified length to the original length. Strain, also sometimes referred to as ironing degree, is a measure of how plastically the volume portion of the blank material is deformed.

Bearing discs so far known according to the prior art are made of parts of material which are folded or bent into the collar part, for example, with a slight degree of deformation (up to 10%-15%), but the thickness of the sheet does not change significantly compared to the starting state. Did. Usually in the case of curved parts only the outer fibrous tissue is extremely stretched at the edges of the sheet. On the contrary, the material of the bearing disk according to the present invention is not produced by bending or embossing, but is pressed in such a way that the cross section is reduced under high pressure conditions. Thus, most of the edges and cores of the blank are flexible. Thus, the degree of deformation for the collar part is between at least 30% -60%, preferably 50% or more, according to the present invention.

The collar portion, which is preferably formed in a hollow cylindrical shape, protrudes upward in the bearing direction, preferably in the lower bearing disk, or preferably in the lower bearing disk, or preferably protrudes downward. The material used for the production of the collar portion is compressed until the wall thickness of the portion of the collar portion projecting axially from the disk becomes thinner than the thickness of the bearing disk at the thickest position. Wall thickness is measured in the radial direction. The thickness of the disk is the principal dimension measured axially in the bearing disk where depressions such as raceways and chamfers are not taken into account. The wall thickness is about 1/3 to 2/3 thinner than the thickness of the bearing disc, preferably about 50% thinner. The thickness of the bearing discs is at least 3 mm.

The raceway for the rolling body is preferably provided by cold forming on the side facing in the opposite direction from the side with the center crystal collar portion of the side of the bearing disc. The surface of the raceway is no longer polished after cold forming as in the construction of the present invention.

The material of the bearing disc is preferably carbon steel, such as C45. The bearing discs are preferably totally hardened. It is also conceivable to further strengthen the resistance to the surface of the raceway only by work hardening rather than curing. This is especially true for spring strut bearings with very low loads.

Upon deformation of the metal, the atoms glide freely within the crystal lattice of the metal. This free sliding of the atomic gap is called displacement. By increasing the displacement density in the tissue, the immobilization process is suppressed. This increases the strength. This process is called work hardening.

The spring strut bearings provided by the present invention can be manufactured economically, have fewer component members compared to the prior art, and are also suitable for high load applications based on the use of bulky discs. Bearings according to the prior art can be replaced with bearings according to the present invention without further modification of the surrounding structure.

The invention is described in more detail according to the following examples.

1 to 4, the directions oriented in the same direction as each of the central axis and the bearing axis and extending vertically in the figure are applied as axial directions, perpendicular to this axial direction and thus horizontal in the figure. Directions extending in the direction are applied as radial directions.

1 shows a spring strut bearing 13 according to an embodiment of the present invention. The spring strut bearing 13 comprises an upper bearing disc 2, a lower bearing disc 14, a rolling body 4 and a cap 5. The bearing disks 2 and 14 are thick in their walls, that is to say formed in a massive structure, which are circular disks. The cap 5 is made of sheet steel, which assembles the bearing discs 2 and 14 and the rolling body 4 into one structural unit.

The bearing disc 14 is made of totally hardened carbon steel and comprises a collar 15, together with the collar 15 to form a molded part made from the annular disc blank 16. Disc blank 16 is shown in FIG. In addition, the bearing disc 14 includes a raceway 24. This raceway is formed on the axially oriented side 28. The groove part 23 is integrally formed in the outer periphery of the side surface 29 oriented in the opposite direction among the side surfaces of the bearing disk 14. The groove portion 23 is an axial undercut portion, and the folded edge 30 of the cap 5 fixes the undercut portion at the rear for the purpose of fixing it with one structural unit.

2 shows the contour of the disc blank 16 before deformation into a solid line. This disc blank 16 is shaped into a bearing disc 14 having a contour shown by broken lines. The volume 17 of the disc blank with the contour shown in solid lines is the same as the volume 18 of the bearing disc 14 produced. The first partial amount of the contoured material shown by the broken line is the partial amount of the disc blank 16 and forms a bearing disc 14 that does not include the collar portion 15 in the completely deformed constituent member. The remaining amount of material in the portion of the disc blank 16 which is not surrounded by the broken line is plastically displaced upon deformation. The portion of the material surrounded by the contours represented by the diameters 19, 20 and the thickness 21 of the disc blank 16 is essentially plastically displaced for shaping the collar portion 15. The diameter of the hole 22 of the disc blank 16 is indicated by reference numeral 19. The diameter of the hole 25 provided in the manufactured bearing disk 14 or in the collar portion 15 of the bearing disk is indicated by reference numeral 20.

In the material of the blank 16, displacement is made for the purpose of axial runout, in order to form a ring-shaped groove 23 circulating in a ring shape in the finished bearing ring 14 and to form a raceway 24 circulating in the ring shape. The part of the material to be determined is determined not only by the contour, which is essentially determined by the thicknesses 21 and 26, but also by the empty volumes of the raceway 24 and the groove 23. In this regard, the material is displaced or displaced in the direction of the bearing shoulder 31 to form the groove 23, thereby forming the bearing shoulder 31. In the completed component member, the groove portion 23 is connected to the bearing shoulder 31 in the axial direction. The volume of material of the bearing shoulder 31 essentially corresponds to the volume of material displaced to form the groove 23.

The collar portion 15 is deformed with a higher degree of strain than that which is applied to the shaping of the bearing disk 14. The wall thickness 27 of the collar portion 15 is about 50% thinner than the thickness 26 of the bearing disc 14 and is at least 50% thinner than the thickness 21 of the disc blank 16.

FIG. 3 is an enlarged view of the portion Z of FIG. 1 to show in detail not to scale. As can be seen from Fig. 3, the wall thickness 27 of the collar portion 15 need not be constant. The wall thickness 27 provided at the thickest position of the portion of the collar portion 15 axially protruding from the bearing disk 14 and formed into a hollow cylindrical shape is the inclined portion 33 or the convex shape 12. The thickness decreases toward the wall thickness 32 provided at the thinnest position. By doing so, the collar part 15 has a basic shape different from the cylindrical shape, for example, the inner part is formed conical and the outer part is formed convex depending on the section. The rims provided on the transitions 11 leading from the side 28 to the collar 15 are alternately curved towards the inner or outer direction. In the figure, the switching section 11 is curved concave inside the material. The material was displaced into the collar 15 so as to provide a transition 11 during deformation.

FIG. 4 shows the spring strut bearing 13 according to FIG. 2 disposed in the upper bearing 10 of the spring strut shown only partially, along the central axis of the piston rod 9 of the shock damper, not shown. It is shown in longitudinal section. The spring strut includes a helical spring 3 in addition to the impact damper. Of this helical spring, only one winding is shown in FIG. The helical spring 3 is supported axially in the spring plate 8 and is guided in the spring plate in the radial direction. On the neck 7 of the spring plate 8 the spring strut bearing 13 is supported not only in the axial and radial directions, but also centered on the central axis 6 side. For this purpose, the spring strut bearing 13 is engaged with the collar 15 in the opening 1 of the neck 7. According to an alternative embodiment, the collar portion can be moved over the edge of the neck portion. The spring strut bearing 13 is supported in the shock absorbing member 40 toward the chassis direction.

1 is a longitudinal sectional view showing the spring strut bearing cut along the bearing axis according to the present invention.

Figure 2 is a longitudinal cross-sectional view showing the blank of the ring disk for producing a bearing disk of the spring strut bearing according to the present invention cut along the central axis of the blank.

3 is a detailed view of the Z portion of FIG.

4 is a longitudinal cross-sectional view showing a state in which the spring strut bearing according to FIG. 2 is disposed on the upper bearing of the spring strut, cut along the central axis of the piston rod of the shock damper.

<Description of main parts of drawing>

1: opening

2: upper bearing disc

3: helical spring

4: rolling body

5: cap

6: central axis

7: neck

8: spring plate

9: piston rod

10: spring strut bearing

11: switching section

12: convex shape

13: spring strut bearing

14: lower bearing disc

15: Calabu

16: disc blank

17: volume of disc blank material

18: Volume of bearing disc material

19: Diameter of the disc blank hole

20: diameter of the hole in the bearing disc

21: thickness of the disc blank

22: hole in the disc blank

23: home

24: Raceway

25: hole

26: thickness of bearing disc

27: wall thickness

28: side of bearing disc

29: side of bearing disc

30: folded edge of cap

31: bearing shoulder

32: wall thickness

33: slope

Claims (14)

A spring strut bearing 13 comprising a bearing disc 14 having a collar portion 15 which extends and protrudes from the bearing disc 14 while being oriented and extending in the same direction with respect to the bearing axis 6. In the spring strut bearing, which part 15 is made of the material of the bearing disc 14 and is thus formed integrally with the bearing disc 14, The bearing disc 14 forms a molded part made from a circular disk blank 16 together with the collar part 15, and the collar part 15 is a deformation degree applied to the molding of the bearing disc 14. Spring strut bearing characterized by being deformed at a higher degree of deformation. The spring strut bearing according to claim 1, wherein the axial strain of the collar portion (15) is at least twice higher than the axial strain of the bearing disk (14). The spring strut bearing of claim 1 wherein the strain is at least 30%. The wall thickness 27 measured according to claim 1, which is oriented toward the bearing axis 6 in the collar portion 15 formed in the hollow cylinder, is oriented in the same direction as the axis at the thickest position of the bearing disc 14. Spring strut bearing, characterized in that it is thinner than the measured thickness (26). 2. Spring strut bearing according to claim 1, characterized in that the bearing disc (14) comprises at least one raceway (24) for the rolling body (4). 6. The raceway (24) according to claim 5, wherein the raceway (24) is a depression formed by the plastic displacement of the material at the axially facing side (28), the raceway (24) being in the axial direction of the side of the bearing disc (14). Spring strut bearing, characterized in that formed on the side 29 facing in the opposite direction of the collar portion (15). 7. The bearing disc (14) according to claim 6, wherein the bearing disc (14) comprises a groove portion (23) which circulates radially outwardly of the side from which the collar portion (15) protrudes, and the groove portion (23) has a bearing shoulder (31) in the axial direction. And the bearing shoulders 31 define the raceway 24 in a radial direction. 8. The spring strut bearing according to claim 7, wherein the volume of the groove portion (23) corresponds to the volume of material forming the shoulder from the raceway (24) to the radially outer rim of the bearing disc (14). 6. Spring strut bearing according to claim 5, characterized in that the raceway of the finished bearing disc (14) comprises a finished surface as a result of plastic deformation. A spring strut bearing comprising a bearing disk 14 having a collar portion 15 which is oriented in the same direction with respect to the bearing axis 6 and extends from and protrudes from the bearing disk 14, wherein the collar portion 15 In the spring strut bearing which is made of the material of the bearing disc 14 and is thus formed integrally with the bearing disc 14, The wall thickness 27 provided in the portion of the collar portion 15 oriented perpendicularly to the bearing axis 6 to the portion protruding from the bearing disk 14 and formed into a hollow cylindrical shape is the width of the bearing disk 14. Spring strut bearing, characterized in that thinner than the thickness (26) in the same direction as the bearing axis (6). 8. The wall thickness (27) provided in the collar portion (15) in a radial direction is provided by 30% to 60% of the thickness (26) provided in the bearing disk (14) in an axial direction. Spring strut bearing, characterized in that the thin. 8. Spring strut bearing according to claim 7, characterized in that the bearing disc (14) is made from totally hardened carbon steel. A spring strut bearing comprising a bearing disc 14 having a collar portion 15 which is oriented in the same direction with respect to the bearing axis 6 and extends from and protrudes from the bearing disc 14, said collar portion 15 In the spring strut bearing made of the material of the bearing disc 14 and thus integrally formed with the bearing disc, The bearing disc 14 forms a molded part made of steel together with the collar part 15, wherein in the bearing disc 14 the thickness 26 in the same direction as the bearing axis 6 is at least 3 mm. Spring strut bearing. 13. The wall thickness 27 according to claim 12, wherein the wall thickness 27, which is provided perpendicularly to the bearing axis 6, is provided in the portion of the collar portion 15 protruding from the bearing disk 14 and formed into a hollow cylinder. Spring strut bearing, characterized in that the disc (14) is thinner than the thickness (26) in the same direction as the bearing axis (6).

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