Freewheeling mechanism having an interlocking connection between a sheet metal cage and a freewheeling member by monolithic doubling of material

Abstract

Freewheeling mechanisms are used, for example, as one-way clutches and often consist of an outer or inner ring with wedge ramps, sometimes a plastic cage, a compression spring, and a roll as a clamping part. They transmit torque in one direction of rotation and are constructed as compact components. A freewheel mechanism (1) is proposed, comprising a freewheel member (3) including a clamp structure (4), further comprising a plurality of clamp portions (5) arranged on the clamp structure (4), and comprising a sheet metal cage (7) for maintaining a distance between the clamp structures (4) in a rotational direction (101), the sheet metal cage (7) being arranged on the freewheel member (3), and the sheet metal cage (7) comprising a coupling rim (8) on its axial side, the coupling rim (8) having a coupling structure (14) for interlocking coupling to the clamp structure (4) so ​​as to be connected to the freewheel member (3) and co-rotate with the freewheel member (3) in the rotational direction (101), the freewheel member (3) being an inner part, the coupling rim (8) having a coupling portion (13), the coupling structure (14) being formed on the inner circumference of the coupling portion (13).

Description

[Technical Field]

[0001] The invention relates to a freewheel mechanism having the features of the preamble of claim 1. [Background technology]

[0002] Freewheel mechanisms, used as one-way clutches, often consist of an outer or inner ring with a wedge ramp, sometimes a plastic cage, a compression spring, and rollers as clamping elements. They transmit torque in one direction and are designed to save space.

[0003] Documents, for example DE 102010052922 A1, disclose a freewheel mechanism cage comprising a base body having two annular, substantially radially extending edge discs which are connected to one another by a plurality of circumferentially adjacent, axially extending connecting struts, thereby forming a gap for at least partially receiving a clamping part.

[0004] The inner ring of the freewheel mechanism is provided with a clamping structure, and rollers having pins on their end faces are movably guided in slots in the edge disc and biased against the clamping structure by wire springs disposed on the sides of the edge disc.

[0005] German Patent Application No. 102011005245 discloses a freewheel mechanism with an internal star, the clamping part of which is guided in a cage. The cage is cup-shaped and has a coupling structure cut out from the bottom of the cup, which is adapted to the ramp shape of the freewheel mechanism ring and is interlocked with it.

[0006] A typical freewheel mechanism is known from German Patent Application Publication No. 102008037972. The freewheel mechanism includes a freewheel member embodied as an outer ring and having a clamping structure. The clamping structure is disposed on the clamping structure and guided within a sheet metal cage. The sheet metal cage is provided with a coupling rim having a coupling structure on one axial side. The coupling structure is used for interlocking coupling of the sheet metal cage to the clamping structure so that the sheet metal cage is held on the freewheel member and co-rotates with the freewheel member in the direction of rotation. The coupling structure is formed on a coupling disc and is concentrically fixed to the base of the sheet metal cage. For this purpose, the coupling rim is provided with a support portion. The support portion, like the coupling structure, extends radially outward. The coupling disc is axially connected to the support portion so that the coupling rim has double the material thickness. Due to the interlocking coupling between the coupling structure and the clamping structure, the sheet metal cage is connected to the outer ring so that it co-rotates with the outer ring in the direction of rotation. Summary of the Invention [Problem to be solved by the invention]

[0007] The underlying object of the present invention is to propose a freewheel mechanism that is designed to be easy to manufacture. [Means for solving the problem]

[0008] This object is achieved by a freewheel mechanism having the features of claim 1. Preferred or advantageous embodiments of the invention arise from the dependent claims, the following description and the accompanying drawings.

[0009] According to the invention, the coupling structure is integrally arranged on the sheet metal cage, the coupling rim has a U-shaped bending region, and the support portion merges with the coupling portion at the bending region.

[0010] The freewheel mechanism is particularly configured as a one-way clutch or an overrunning clutch. The freewheel mechanism can be used, for example, as an indexing mechanism, a reverse arrester, an overrunning clutch, etc. The freewheel mechanism preferably performs an overrunning function and / or a holding function. The freewheel mechanism can be used, for example, in a transmission for an automobile.

[0011] The clamping structure has a plurality of wedge ramps extending in the rotational direction relative to the rotation axis, in particular the clamping structure has more than three, preferably more than six, in particular more than ten such wedge ramps.

[0012] The freewheel mechanism has a plurality of clamping members, each preferably configured as a roller, in particular as a cylindrical roller. The freewheel mechanism defines a rotation axis, and the rotation axes of the rollers are aligned parallel to the rotation axis. Preferably, one clamping member is assigned to each wedge ramp of the freewheel mechanism.

[0013] The freewheel mechanism has a sheet metal cage for spacing the clamping parts in the rotational direction. In particular, the sheet metal cage provides a spring support for the clamping parts in the rotational direction. For this purpose, the sheet metal cage can serve as a support for a spring device that is arranged within the sheet metal cage and applies a spring force to the clamping parts in the rotational direction. In particular, the freewheel mechanism includes a spring device.

[0014] On one axial side, the sheet metal cage has a coupling rim, which in turn has a coupling structure for interlocking coupling to the clamping structure, whereby the sheet metal cage is connected to the freewheel member for co-rotation with the freewheel member in the rotational direction by the interlocking coupling between the coupling structure and the clamping structure.

[0015] Preferably, the freewheel element has a positive clamping structure. The sheet metal cage, in particular the coupling rim, is preferably at least partially or completely complementary and / or counter-formed and / or negative, with the negative having a coupling structure and / or shape that fits into the positive clamping structure. Preferably, the clamping structure of the freewheel element and / or the coupling structure of the sheet metal cage and / or the coupling rim extend in an axial direction parallel to the rotation axis and / or have a constant cross section in the axial direction relative to the rotation axis. In this embodiment, the sheet metal cage can be easily pressed onto the freewheel element. At least the coupling structure and / or shape of the negative is preferably configured to be non-rotationally symmetrical and / or deviate from a constant diameter. For example, the negative coupling structure and / or shape is configured as a wavy and / or uneven edge.

[0016] In a preferred embodiment of the invention, a contact area is formed between the coupling rim and the freewheeling member, in particular the outer circumferential surface of the clamping structure, where the coupling rim and the freewheeling member are in interlocking contact. The contact area extends in the direction of rotation about the rotation axis over at least 50%, advantageously at least 80%, in particular at least 95% of the outer circumferential length of the freewheeling member in the circumferential direction. In particular, the coupling rim contacts the wedge ramp over at least 50%, preferably at least 80%, in particular at least 95% of the outer circumferential length in the direction of rotation. The contact area can be formed continuously in the direction of rotation, but it can also be divided into a number of individual areas. A high overlap in the direction of rotation creates a large coupling area between the sheet metal cage and the freewheeling member, which makes the freewheeling mechanism particularly susceptible to loads.

[0017] In particular, the contact area is defined as extending axially over at least 0.5 mm, preferably over at least 1 mm, in particular over at least 1.5 mm.

[0018] The freewheel element is configured as an inner part. In this case, the clamping structure is arranged on the outer periphery of the inner part. The inner part can be configured as an inner ring or as a shaft section, for example, of a solid or hollow shaft. In particular, the freewheel mechanism is configured as an internal star-type freewheel mechanism. The coupling structure is formed on the inner periphery of the coupling part. The coupling part of the coupling rim therefore extends radially inward to form an interlocking connection in the rotational direction at the contact area between the sheet metal cage and the freewheel element. By arranging the coupling structure integrally with the sheet metal cage, the freewheel mechanism can be implemented in a manner that is suitable for manufacturing.

[0019] The support portion extends radially outward, and the coupling portion is joined to the support portion. Particularly preferably, the coupling portion and the support portion extend in each case in a radial plane relative to the rotation axis. In particular, the support portion and the coupling portion lie directly opposite each other, i.e., lie flatly on top of each other, so that the coupling rim has twice the material thickness due to the coupling portion and the support portion. This configuration, on the one hand, improves ease of manufacture and, on the other hand, increases the stability and / or structural rigidity of the sheet metal cage.

[0020] The coupling rim has a U-shaped bending region, and the support portion merges into the coupling portion at the bending region, which is an advantageous manufacturing-oriented implementation, since the U-shaped bending region allows the coupling portion and the support portion to be arranged adjacent to each other in parallel.

[0021] In a preferred further development of the invention, the sheet metal cage has a neutral rim on its other axial side, i.e., on the side opposite the coupling rim, which extends radially outward. In particular, the neutral rim is formed from a single layer. The sheet metal cage has a U-shape in longitudinal cross section, with one upright leg formed by the neutral rim and the other upright leg formed by the coupling rim. The associated axial side of the sheet metal cage is supported and reinforced by the neutral rim. Overall, the U-shaped configuration exhibits very high inherent stability and is easy to engineer.

[0022] In a preferred embodiment of the present invention, the inner circumference of the neutral rim is circular and / or is not coupled to the clamping structure and / or the freewheel member in the direction of rotation. Therefore, the sheet metal cage is driven only by the coupling portion of the coupling rim, while the neutral rim is decoupled from the freewheel member in the direction of rotation. This embodiment allows for a cost-effective arrangement with a coupling structure on only one axial side, thereby reducing manufacturing costs. The free inner diameter of the neutral rim is preferably narrow enough so that the sheet metal cage can be supported radially via the neutral rim on the freewheel member, in particular on the clamping structure.

[0023] In a preferred embodiment of the present invention, the sheet metal cage has a plurality of web sections, and the clamping portions are arranged between the web sections. The web sections serve in particular to guide the clamping portions in the direction of rotation. In particular, the web sections comprise holding portions for holding the spring device. The web sections are integrally formed within the sheet metal cage. In particular, the web sections are made from a common base piece like the sheet metal cage.

[0024] The web portion defines a free inner diameter, and the coupling portion with the coupling structure projects into the free inner diameter, and / or the neutral rim is defined radially inward by the free inner diameter. Thus, the free inner diameter, which corresponds, inter alia, to the maximum outer diameter of the freewheel member, is determined by the neutral rim and the web portion. The coupling portion with the coupling structure projects radially inward into the free inner diameter. This allows the web portion and / or the neutral rim to rest on the clamping structure, and for the coupling structure to interlock with the clamping structure.

[0025] In particular, starting from the web portion and / or the free inner diameter, the coupling rim extends radially outward within two material thicknesses and / or radially inward within a single layer.

[0026] Particularly preferably, the sheet metal cage is integrally formed from a common piece of material, in particular in the form of a steel sheet. Preferably, the sheet metal cage is in the form of a formed cage. In particular, the sheet metal cage is configured as a formed part produced without cutting, in particular as a deep-drawn part as a base body.

[0027] Advantageously, the sheet metal cage is pressed axially onto the freewheel element such that the coupling structure engages the clamping structure in a form-locking manner in the direction of rotation and the neutral rim rests with its inner periphery in contact with the clamping structure, which preferably extends axially further than the axial extent of the sheet metal cage so that it cannot accidentally slip off the clamping structure.

[0028] The retaining portion of the sheet metal cage is preferably made from a base material of the sheet metal cage, which is first separated, in particular punched out, and then bent so that it can form a base or bearing part for the spring device.

[0029] Optionally, the freewheel mechanism has an outer ring or outer ring portion having a cylindrical raceway for the clamping portion.

[0030] Further features, advantages and benefits of the present invention will become apparent from the following description of preferred exemplary embodiments of the invention and the accompanying drawings. [Brief explanation of the drawings]

[0031] [Figure 1] 1 shows a schematic three-dimensional view of a freewheeling mechanism as an exemplary embodiment of the present invention; [Figure 2] 2 shows a schematic three-dimensional view of the sheet metal cage of the freewheel mechanism of FIG. 1 with the clamping part inserted; [Figure 3] 1 is a schematic three-dimensional view of a single sheet metal cage of a freewheeling mechanism. [Figure 4a] 1 shows a schematic longitudinal section through the sheet metal cage of the previous figure; [Figure 4b] 1 shows a schematic longitudinal section through the sheet metal cage of the previous figure; [Figure 5] 1 shows a schematic enlarged detail view of the sheet metal cage of the previous figure; DETAILED DESCRIPTION OF THE INVENTION

[0032] FIG. 1 shows a schematic three-dimensional view of a freewheel mechanism 1 according to an exemplary embodiment of the present invention. The freewheel mechanism 1 is formed on an intermediate or end portion of a shaft 2. The freewheel mechanism 1 has a freewheel member 3, which is formed by a shaft portion. In an alternative exemplary embodiment, the freewheel member 3 can be configured as an inner ring. In this exemplary embodiment, the freewheel member 3 is configured as an inner portion. A clamping structure 4 is attached to the freewheel member 3. The clamping structure 4 can be molded, for example; alternatively, the clamping structure 4 is separately introduced into the freewheel member 3. In other exemplary embodiments, the clamping structure 4 can also be formed on the mounting portion of the shaft 2 or the freewheel member 3. The freewheel mechanism 1 defines a rotation axis 100.

[0033] The freewheel mechanism 1 has a plurality of clamping members 5, which are configured as cylindrical rollers. The clamping members 5 are mounted on a clamping structure 4 and can move in a rotational direction 101 on the clamping structure 4. In more detail, the clamping structure 4 has a plurality of wedge ramps 6 extending, in particular ascending, in the rotational direction 101, which form tracks for the clamping members 5. In the rotational direction 101, the wedge ramps 6, together with the cylindrical tracks of an outer ring (not shown), reduce the radial installation space for the clamping members 5 so that the clamping members 5 can assume their clamping position. The clamping structures 4 and / or the wedge ramps 6 extend with a constant cross-sectional shape on the freewheel member 3. The clamping structure 4 forms a positive shape of the freewheel member 3 rotating around a rotational axis 100.

[0034] The freewheel mechanism 1 has a sheet metal cage 7 for spacing the clamping parts 5 in the direction of rotation 101. The sheet metal cage 7 is arranged on the freewheel member 3, in particular, pressed axially thereon. The sheet metal cage 7 has a coupling rim 8 on one axial side and a neutral rim 9 on the other side. The coupling rim 8 and the neutral rim 9 extend radially outward and in a radial plane relative to the rotation axis 100. The clamping parts 5 are disposed between the coupling rim 8 and the neutral rim 9. Furthermore, the sheet metal cage 7 has a plurality of web portions 10 that extend between the coupling rim 8 and the neutral rim 9 and connect them together.

[0035] The web portion 10 is joined to a retaining portion 11, which is configured in particular as a lug and which is bent radially outward and aligned approximately radially. A spring device 12, which is configured as a compression spring acting tangentially to the direction of rotation, is arranged on the retaining portion 11. The spring device 12 is arranged between the clamping portion 5 and the retaining portion 11 in the direction of rotation 101, so that the clamping portion 5 rides up against the spring force onto the wedge ramp 6.

[0036] The sheet metal cage 7 has a coupling portion 13 on the coupling rim 8, which has a coupling structure 14 on its inner circumference. The coupling structure 14 serves to interlock the sheet metal cage 7 with the clamping structure 4 in the rotational direction, connecting the sheet metal cage 7 to the freewheel member 3 and co-rotating therewith. While the clamping structure 4 has a positive shape, the coupling structure 14 has a negative shape that matches the positive shape. For example, the contact area is formed by, or at least formed together with, the wedge ramp 6 and the coupling portion 13. The coupling portion 13 and the freewheel member 3 can be embodied in such a way that a force-locking connection and / or a press fit is provided between the two components in the region of the coupling structure 14 or the clamping structure 4.

[0037] 2 is a schematic three-dimensional view of the sheet metal cage 7 with the clamping parts 5 inserted and the spring devices 12 attached. From this illustration, it can be seen that the web regions 10 and the neutral rim 9 together define a uniform free inner diameter 102, and the coupling parts 13 with the coupling structures 14 project into the free inner diameter 102. Likewise, the clamping parts 5 also project into the free diameter 102. The web regions 10 can, for example, rest on the tangential surfaces 15 of the clamping structures 4 (FIG. 1). The neutral rim 9 can, for example, rest at least partially on the clamping structures 4. In this case, the inner circumferences of the web regions 10 and / or the neutral rim 9 can rest in a press-fit and / or for-lock manner on the freewheel member 3 to prevent axial movement of the sheet metal cage 7 relative to the freewheel member 3.

[0038] FIG. 3 shows the sheet metal cage 7 as a separate part, and it can also be seen in this figure that the sheet metal cage 7 has double the material thickness at the coupling rim 8 .

[0039] However, this can be better seen in Figures 4a and 4b, which respectively show a longitudinal section through the sheet metal cage 7. From the illustration it can be seen that the neutral rim 9 is configured as a collar or radial flange which lies in a radial plane relative to the axis of rotation 100 and which, starting from the web portion 10, extends exclusively radially outwards.

[0040] The coupling rim 8, on the other hand, has a support portion 16 which joins the web portion 10, lies in a radial plane relative to the rotation axis 100 and extends radially outward. Parallel to and immediately adjacent to the support portion 16, the coupling rim 8 has a coupling portion 13 which also extends in a radial plane relative to the rotation axis 100 and which, together with the coupling structure 14, projects into the region of the free inner diameter 102.

[0041] Between the support portion 16 and the coupling portion a folding region 17 is shown in longitudinal section, where the support portion 16 merges into the coupling portion 13 .

[0042] Figure 5 shows a detail of Figures 4a and 4b, in which the coupling limb 8 and the neutral limb 9 are shown arranged parallel to one another. The web portion 10 is again visible, integrally connecting the two limbs 8, 9 to one another. Furthermore, the retaining portion 11 is visible, which protrudes at least partially into the free inner diameter by bending. As can be seen from the illustration, the coupling structure 14 replicates the ramp 6 in terms of contour so that an interlocking connection is formed.

[0043] The sheet metal cage 7 is produced from a single piece of material by a process sequence of forming and cutting from a common piece of material, in this case steel sheet. In particular, the sheet metal cage 7 is produced by cold forming. For example, one of the rims 8, 9 can be formed as a flange portion during deep drawing. If the coupling rim 8 is produced as a flange portion during deep drawing, in the subsequent method document, the coupling portion 13 is produced from the coupling rim 8. Alternatively, the neutral rim 9 can be configured as a flange portion during deep drawing. The material used is a steel material, as very high temperatures are likely to occur, especially in the vehicle industry. [Explanation of symbols]

[0044] 1 Freewheel mechanism 2 shafts 3 Freewheel components 4. Clamp structure 5 Clamp section 6 Wedge Lamp 7 Sheet Metal Cage 8 Coupling rim 9 Neutral Rim 10 Web Section 11 Holding part 12 Spring Device 13 Coupling part 14 Coupling Structure 15 Tangential surface 16 Support part 17. Folding Area 100 Rotation Axis 101 Rotation direction 102 Free inner diameter

Claims

1. A freewheel mechanism (1), a freewheel member (3) having a clamping structure (4); a plurality of clamping members (5), the clamping members (5) being disposed on the clamping structure (4); a sheet metal cage (7) for spacing the clamping members (5) apart in a rotational direction (101), the sheet metal cage (7) being disposed on the freewheel member (3) and having a coupling rim (8) at one axial end thereof, the coupling rim having a coupling structure (14) for meshingly connecting to the clamping structure (4) so ​​that the sheet metal cage (7) is held on the freewheel member (3) and co-rotates with the freewheel member (3) in the rotational direction (101); The freewheel member (3) is configured radially inside the sheet metal cage (7), the coupling rim (8) has a coupling portion (13) and a support portion (16), and the coupling structure (14) is formed on the inner periphery of the coupling portion (13); the support portion (16) extends radially outward, the coupling portion (13) adjoins the support portion (16) such that the coupling rim (8) has double the material thickness; The freewheel mechanism (1) is characterized in that the coupling structure (14) is integrally arranged on the sheet metal cage (7), the coupling rim (8) has a U-shaped bending region (17), and the support portion (16) joins the coupling portion (13) at the bending region (17).

2. 2. The freewheel mechanism (1) according to claim 1, characterized in that the sheet metal cage (7) has a neutral rim (9) at the other axial end, the neutral rim (9) extending radially outward.

3. 3. The freewheel mechanism (1) according to claim 2, characterized in that the inner circumference of the neutral rim (9) is circular and / or is not coupled to the clamping structure (4) in the direction of rotation (101).

4. 3. The freewheel mechanism (1) according to claim 2, characterized in that the sheet metal cage (7) has a plurality of web portions (10), the clamping member (5) is disposed between the web portions (10), the web portions (10) define an inner diameter space (102), the coupling portion (13) having the coupling structure (14) protrudes into the inner diameter space (102), and the neutral rim (9) is defined radially inward by the inner diameter space (102).

5. 2. The freewheel mechanism (1) according to claim 1, wherein the sheet metal cage (7) is made integrally from a common piece of material.

6. 2. The freewheel mechanism (1) according to claim 1, characterized in that the sheet metal cage (7) is configured as a molded part that is manufactured without cutting.

7. 3. The freewheel mechanism (1) according to claim 2, characterized in that the sheet metal cage (7) is pressed axially onto the freewheel member (3) so that the coupling structure (14) interlocks with the clamping structure (4) in the rotational direction (101) and the neutral rim (9) rests with its inner periphery in contact with the clamping structure (4).

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