Overload protection clutch with segmented coil spring and coil spring

Abstract

The utility model relates to an overload protection clutch (1) which is provided with an input side friction disc (2) and at least one output side friction disc (4), and the output side friction disc tightly presses the input side friction disc (2) in a friction force locking mode through an annular coil spring (3) which is installed in a pre-tightening mode. The coil spring (3) consists of a plurality of arc segments (5) which are connected to one another in a form-fitting manner. The utility model further relates to a coil spring.

Description

Technical Field

[0001] The utility model relates to an overload protection clutch, which has an input side friction disk and at least one output side friction disk, wherein the output side friction disk is pressed against the input side friction disk in a friction locking manner by means of a pre-tightened annular disc spring. The utility model also relates to the disc spring itself. Background Art

[0002] Universal overload protection clutches (also referred to as torque limiters or slip clutches) are known in the prior art. Such overload protection clutches are known, for example, from DE 20 2019 106 788 U1. The overload protection clutch is simultaneously implemented as a multi-flange torsional vibration damper.

[0003] For such overload protection clutches, it is also known that the disc spring should be formed as compactly as possible in the axial direction and should be designed as simply as possible. In this case, the disc spring is usually designed as a constant surrounding force edge (purely annular and without radially or axially protruding tongues). It is also known to produce corresponding disc springs by punching rings out of metal sheets. However, this production process has the disadvantage that a large amount of stamping waste is generated during the forming of the disc spring. In particular, the disc-shaped parts punched out inside the disc spring can no longer be used. Utility Model Content

[0004] The object of the present invention is therefore to provide a disc spring for an overload protection clutch, wherein the disc spring should be mass-produced as efficiently as possible while at the same time minimizing the weakening of the base material of the disc spring during the manufacturing process.

[0005] According to the present invention, the object is achieved in the following manner: the spiral spring is composed of a plurality of circular arc segments connected to each other in a form-fitting manner.

[0006] Compared to rings in the form of stamped products, the individual arc segments can be produced from sheet metal with significantly less stamping waste. At the same time, due to the form-fit connection, the arc segments can be produced from a suitable metal, such as steel, because the microstructure of the arc segments is not adversely affected by the connection process. The elastic properties of the metal are therefore not particularly adversely affected.

[0007] Further advantageous embodiments are protected by the dependent claims and are described in detail below.

[0008] It is therefore also advantageous if the circle segments are designed as identical parts. This makes the manufacturing process as efficient as possible.

[0009] It is also advantageous that the arc segments engage / support each other in a form-fitting manner in the circumferential direction and radial direction of the overload protection clutch. The arc segments can thus be assembled as simply as possible. It has been found that it is particularly advantageous that the arc segments are pushed into each other in the axial direction while forming a form-fitting connection.

[0010] Furthermore, a good compromise between simple construction and low installation space requirement can be achieved if the finished spiral spring is tapered in the axial direction.

[0011] It should be noted that the spiral spring as a whole is preferably implemented as a pure annular spiral spring, that is, it has no radial or axial protrusions, and therefore has a constant inner diameter and a constant outer diameter over its entire circumference. Therefore, the structure of the spiral spring can be as simple as possible.

[0012] Furthermore, it has been found to be particularly advantageous if the arc segments are deformed in the state in which they form the annular spiral spring, so that the arc segments are axially fixedly connected to one another. For this purpose, a plastic deformation of the form-fit connection between the arc segments occurs during the conical deformation / tapering of the spiral spring, whereby the arc segments are fixed to one another in the axial direction. However, it is particularly preferred that the selected installation angle / adjustment angle / setting angle does not allow axial slippage of the form-fit connection between the arc segments. The form-fit connection of the arc segments is twisted about the reversal point of the spiral spring during installation.

[0013] In order to ensure that the spiral spring can be used properly, it is also expedient if the circular arc segment is made of spring steel.

[0014] It is also advantageous if the first form-fit connection between two circumferentially adjacent / directly connected arc segments has at least one convex spherical head region on one arc segment, which engages in a first recess complementary thereto on the other arc segment. This allows the form-fit connection to be manufactured as simply as possible.

[0015] Alternatively or additionally, it is also advantageous if the second form-fit connection between two circumferentially adjacent arc segments has at least one hook-shaped area on one arc segment, which engages in a second recess complementary thereto on the other arc segment. Such a hook shape can produce a form-fit connection that is as strong as possible.

[0016] Alternatively or in addition to the first form-fit connection and / or the second form-fit connection, it is also advantageous if a third form-fit connection between two circumferentially adjacent arc segments has at least one radial snap-in lug on one arc segment, which snap-in lug engages in a third recess complementary thereto on the other arc segment. This also allows a form-fit connection that is easy to manufacture to be provided.

[0017] The utility model also relates to a disc spring which has a plurality of circular arc segments, and the circular arc segments are connected to each other in a shape-fitting manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention is described in detail below with reference to the accompanying drawings, in which different embodiments are also shown.

[0019] Figure 1 A perspective view of the overload protection clutch according to the present invention cut along the longitudinal direction according to the first embodiment is shown, through which the structure of the overload protection clutch can be seen in detail.

[0020] Figure 2 The application of the utility model is shown in Figure 1 Front view of the coil spring in

[0021] Figure 3 Shown according to Figure 2 Detailed view of the connection region between two adjacent circular arc segments of a spiral spring, wherein a plurality of individual positive connections / connection sections are present,

[0022] Figure 4 A detailed view of the connection region between two adjacent circular arc segments of a spiral spring according to a second embodiment is shown, wherein a positive connection with a convex spherical head region is present, and

[0023] Figure 5 A detailed view of the connection area between two adjacent arc segments of a spiral spring according to a third embodiment is shown, wherein Figure 3 Compared to the first exemplary embodiment, only a positive connection with a hook-shaped region is present. DETAILED DESCRIPTION

[0024] The accompanying drawings are only schematic and are only used for understanding the present invention. The same elements are provided with the same reference numerals.

[0025] exist Figure 1 The structure of the overload protection clutch 1 according to the utility model is clearly shown in the first embodiment. The overload protection clutch 1 is preferably installed in the drive system of a motor vehicle. More preferably, the overload protection clutch 1 is part of a torsional vibration damper, which is not shown in detail here for the sake of clarity.

[0026] The overload protection clutch 1 has an input-side friction disk 2, which is also alternatively referred to as a support disk. The input-side friction disk 2 has friction linings 21a and 21b on its two end sides / axial sides, respectively. Therefore, the first friction lining 21a is mounted on the first axial side of the input-side friction disk 2, and the second friction lining 21b is mounted on the second axial side of the input-side friction disk 2 that is away from the first axial side.

[0027] The friction linings 21a, 21b are in frictional contact / frictional locking contact with the output-side friction disk 4. Each output-side friction disk 4 is referred to below as a mating disk 15a, 15b. The mating disks 15a, 15b are also connected to the corresponding torque output of the overload protection clutch 1 during operation. The two mating disks 15a, 15b are arranged at a specific axial spacing from each other and are connected to each other so as not to rotate relative to each other. For this purpose, a rivet element 16 is used in a conventional manner, by which the two mating disks 15a, 15b are connected to each other.

[0028] It can be seen that a gap is formed axially between the counter disks 15a, 15b, into which the input-side friction disk 2 is inserted with its two friction linings 21a, 21b. The first counter disk 15a rests on the first friction lining 21a, while the second counter disk 15b rests on the second friction lining 21b.

[0029] The disc spring 3 (whose structure will be described in detail below) is installed in such a way that the disc spring presses the output side friction disk 4 / counter disk 15a, 15b axially onto the input side friction disk 2 with a specific preload force, thereby forcing friction contact. Therefore, the overload protection clutch 1 is implemented as a friction clutch in a common manner, and the friction clutch is closed by a specific preload force.

[0030] The disc spring 3 is mounted in an axially prestressed manner between an additional support disk 17 , also referred to as housing / cover, and a first counter disk 15 a .

[0031] pass Figure 2 and Figure 3 The structure of the spiral spring 3 can be seen more clearly. The annular spiral spring 3 consists of a plurality of, here three, individually formed circular arc segments 5. The circular arc segments 5 are connected to each other in a form-fitting manner. The circular arc segments 5 are constructed as identical components.

[0032] In the first exemplary embodiment, each circle segment 5 is connected in a form-fitting manner to the circle segment 5 adjacent thereto on its circumferential sides 18 a , 18 b facing away from each other in the circumferential direction, wherein a plurality of individual form-fitting connections / form-fitting sections are present.

[0033] The form-fit connection 9 (hereinafter referred to as the second form-fit connection 9) has a hook-shaped area 10 on the protrusion extending from the first circumferential side 18a of the arc segment 5. The hook-shaped area 10 engages in the (second) recess 11 of the protrusion extending on the second circumferential side 18b of the adjacent arc segment 5, so that the two arc segments 5 are connected to each other in a form-fitting manner not only in the radial direction but also in the circumferential direction.

[0034] In this embodiment, the second circumferential side 18 b has a hook region 10 which is designed complementary to the hook region 10 of the first circumferential side 18 a and which likewise engages in a (second) recess 11 on the first circumferential side 18 a .

[0035] Furthermore, on the protrusion of the arc segment 5 forming the hook-shaped region 10, there are fingers 19a, 19b extending in the circumferential direction and arranged in the radial direction, which are bent / around to form a (third) recess 14. The snap-in lug 13 of the other arc segment 5 is engaged in the third recess 14 in a form-fitting manner in the circumferential direction and in the radial direction. Thus, in the circumferential direction, there are further (third) form-fitting connections 12 at the two sides of the (second) form-fitting connection 9 that face away from each other.

[0036] refer to Figures 1 to 3 It can also be seen that the disc spring 3 is arranged obliquely / conically in the axial direction. Therefore, the disc spring 3 has in particular a tapered radial outer edge and a tapered axial end side. Preferably, the disc spring 3 presents a tapered shape after the arc segments 5 are pushed into each other / connected to each other in a form-fitting manner. By reshaping the entire disc spring 3 accordingly, the arc segments 5 can in principle be plastically deformed so that the arc segments are deformed / connected to each other in an axial direction that cannot be disassembled. However, it is particularly preferred that the individual arc segments 5 are prevented from loosening again from each other mainly in the following way, that is, the adjustment angle / setting angle does not allow the corresponding form-fitting connection 6, 9, 12 to slide out axially between the arc segments 5. When arranged, the form-fitting connection 6, 9, 12 is twisted around the reversal point of the disc spring 3.

[0037] As a preferred material, the circular arc segment 5 is made of spring steel.

[0038] Finally Figure 4 and Figure 5 2 shows two further embodiments of the disc spring 3. The other basic structures of the overload protection clutch 1 constructed according to these embodiments correspond to the first embodiment, so for the sake of simplicity, only the main differences from the first embodiment are identified below.

[0039] exist Figure 4 In the embodiment, an alternative (first) form-fit connection 6 is provided between adjacent arc segments 5, which has a convex spherical head region 7 extending in the circumferential direction on the first circumferential side 18a of the arc segment 5. The head region 7 engages in a form-fitting manner in a (first) recess 8 which is designed complementary thereto. In particular, the head region 7 is surrounded by two clamping arm regions 20a, 20b surrounding the first recess 8 to ensure a form-fitting connection in the radial direction and in the circumferential direction.

[0040] Finally, in Figure 5 As shown in Figure 3 As an alternative, the two further third form-fit connections 12 can also be omitted. Figure 5 In the embodiment, only the second form-fit connection 9 is implemented.

[0041] It should be pointed out that different form-fitting connections 6, 9 and 12 can also be freely combined with each other in principle and can be used simultaneously in one spiral spring 3. Figure 2 Each circle segment 5 is designed as an identical component, so that the same positive connection always exists between the individual connecting regions of the circle segments 5 .

[0042] For the sake of completeness, it is pointed out that the specific directions used: axial, radial and circumferential are to be understood with reference to the central rotation axis 22 of the overload protection clutch 1. The axial / axial direction is thus understood as a direction along / parallel to the rotation axis 22, the radial / radial direction is understood as a direction perpendicular to the rotation axis 22, and the circumferential direction is understood as a direction along a circular line that is concentric with the rotation axis 22.

[0043] In other words, according to the invention, the disc spring 3 is divided into a plurality of segments (circular arc segments 5). The individual (stamped) segments are then connected to one another via form-fitting connections (required to absorb forces in the radial and tangential / circumferential directions), arranged in a bending tool, and finally installed in the torque limiter (overload protection clutch 1) in the desired installation position. In the installed state, the individual segments can no longer be separated from one another as long as the installation height is less than twice the material thickness.

[0044] The stop tabs or projections on the adjacent components serve to support the outer diameter of the spiral spring 3 .

[0045] The spiral spring 3 can be divided into at least two, but in principle any number of, sections. Figure 2 120° arc segments, i.e. three spring segments (circular arc segments 5) are shown by way of example. The implementation of this embodiment (120° arc segments) by stamping technology can save about 70% of material compared to previous production methods. In this case, it should be noted that in addition to the elimination of the inner region, a smaller strip width can be used compared to the original (circular) spiral spring. The width of the arc segment is smaller than the outer diameter of the finished spiral spring 3.

[0046] There are many different embodiments for the design of the arc segment connection. Here, the force transmission of the form-fit connection is always ensured in the circumferential and radial directions of the finished spiral spring 3. In the operating state of the spiral spring 3, radial and tangential forces occur, which are absorbed by the connection.

[0047] exist Figures 3 to 5 An exemplary embodiment of the end connection is shown in . The connection can have, for example, hooks, tabs, etc. in the form of a puzzle or other designs.

[0048] Reference numerals list

[0049] 1 Overload protection clutch

[0050] 2 Input side friction disc

[0051] 3 Coil spring

[0052] 4 Output side friction disc

[0053] 5 Arc segments

[0054] 6 First form-fit connection

[0055] 7 Head area

[0056] 8 first recess

[0057] 9 Second form-fit connection

[0058] 10 Hook area

[0059] 11 Second recess

[0060] 12 Third form-fit connection

[0061] 13 Engaging lugs

[0062] 14 Third recess

[0063] 15a First Pairing Plate

[0064] 15b Second pairing plate

[0065] 16 Riveting elements

[0066] 17 Support plate

[0067] 18a First circumferential side

[0068] 18b Second circumferential side

[0069] 19a First finger

[0070] 19b Second finger

[0071] 20a First clamp arm area

[0072] 20b Second clamp arm area

[0073] 21a First friction lining

[0074] 21b Second friction lining

[0075] 22 Axis of rotation.

Claims

1. An overload protection clutch (1), comprising an input-side friction disk (2) and at least one output-side friction disk (4), wherein the output-side friction disk is pressed against the input-side friction disk (2) by means of a preloaded annular disc spring (3) in a friction-locking manner, characterized in that: The disc spring (3) is composed of a plurality of circular arc segments (5) which are connected to each other in a form-fitting manner.

2. The overload protection clutch (1) according to claim 1, characterized in that: The circular arc segments (5) are constructed as identical components.

3. The overload protection clutch (1) according to claim 1, characterized in that: The circular arc segments (5) engage with each other in a form-fitting manner in the circumferential direction and radial direction of the overload protection clutch (1).

4. The overload protection clutch (1) according to claim 2, characterized in that: The disc spring (3) is tapered in the axial direction.

5. The overload protection clutch (1) according to claim 1, characterized in that: The arc segments (5) are deformed in such a way that they are connected to one another in an axially fixed manner when the arc segments form an annular disc spring (3).

6. The overload protection clutch (1) according to claim 1, characterized in that: The circular arc segment (5) is made of spring steel.

7. The overload protection clutch (1) according to claim 1, characterized in that: A first form-fit connection (6) between two circumferentially adjacent arc segments (5) has at least one convex spherical head region (7) on one arc segment (5), which engages in a first recess (8) complementary to the head region on the other arc segment (5).

8. The overload protection clutch (1) according to claim 1, characterized in that: A second form-fit connection (9) between two circumferentially adjacent arc segments (5) has at least one hook region (10) on one arc segment (5), which engages in a second recess (11) complementary to the hook region on the other arc segment (5).

9. The overload protection clutch (1) according to any one of claims 1 to 8, characterized in that: A third form-fit connection (12) between two circumferentially adjacent arc segments (5) has at least one radial snap-in lug (13) on one arc segment (5), which engages in a third recess (14) on the other arc segment (5) that is complementary to the snap-in lug.

10. A disc spring (3) having a plurality of circular arc segments (5), characterized in that: The circular arc segments (5) are connected to each other in a form-fitting manner.

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