Friction plate having groove pattern formed by friction lining pad

Abstract

The present invention relates to a friction plate (19) comprising a carrier plate (18), a plurality of first friction lining pads (41-43) having a first pad shape and a plurality of second friction lining pads (51-53) having a second pad shape, in which an annular groove pattern (10) is produced by an arrangement of first friction lining pads (41-43) arranged radially outwardly to the center and second friction lining pads (51-53) arranged radially inwardly, said arrangement being repeated in the circumferential direction and separated by dividing grooves (31-37), the first friction lining pads (41-43) and the second friction lining pads (51-53) being separated from each other by dividing grooves (33, 34). The first pad shape of the first friction lining pads (41-43) is designed as a combination of a triangular shape located radially outward and a diamond shape located radially in the center, preferably with an embossed groove (40) located between the triangular shape and the diamond shape, and the second pad shape of the second friction lining pads (51-53) is designed as a pentagonal shape designed as a combination of a triangular shape and an immediately adjacent rectangular shape.

Description

[Technical field]

[0001] The present invention relates to a groove pattern for a friction plate having the features of the preamble of claim 1. [Background technology]

[0002] Grooves or groove patterns, also called pad shapes in the context of this document, are used to cool the plates by oil flow, even when the moving elements are closed. They break through the oil film and thus stabilize the friction coefficient. This creates the desired friction behavior when moving. The idling behavior is improved and the drag torque is reduced.

[0003] The scope of application of the present invention is as follows: Wet multi-plate clutches and brakes are widely used in conventional power-shiftable transmissions, in new hybrid modules in heavy-duty drivetrains or in shiftable e-axles, where they represent high-performance heavy-duty components. The demand for reduced CO2 emissions and improved efficiency of drivetrains in automotive applications is of paramount importance. In addition to reducing the load-independent losses in the moving elements, thermal loads and suitable cooling must be taken into account. The groove pattern of the friction plates plays a central role in the trade-off between friction properties, thermal management and efficiency. (See Figure 1)

[0004] EP 3 354 921 A1 discloses an annular wet-running friction lining having a groove connecting the inner and outer periphery of the friction lining.

[0005] DE 10 2018 003 829 A1 discloses an annular wet-running friction lining with a groove connecting the inner and outer circumference of the friction lining, the outer circumference of which has a course that deviates from a circular course. Summary of the Invention [Problem to be solved by the invention]

[0006] The invention is based on the objective of minimizing drag losses in the case of friction plates (see FIG. 2) and improving cooling capacity by means of a suitable groove pattern. [Means for solving the problem]

[0007] This object is achieved by a groove pattern having the features of claim 1.

[0008] Thus, a groove pattern for a friction plate according to the invention provides that the groove pattern is formed by a first friction lining pad having a first pad shape and a second friction lining pad having a second pad shape, the groove pattern providing a ring-like arrangement of a first pad shape arranged radially outwardly to the center and a second pad shape arranged radially inwardly, repeated in the circumferential direction and separated by a dividing groove, the first pad shape and the second pad shape being separated from each other by a dividing groove, The first pad shape is designed as a combination of a triangular, radially outwardly disposed shape and a diamond, radially centrally disposed pad shape, and the second pad shape is designed as a pentagonal shape designed as a combination of a triangular shape and an immediately adjacent rectangular shape.

[0009] In a preferred embodiment, the first pad feature is an embossed groove.

[0010] In a particularly preferred embodiment, the embossed grooves are arranged between triangular shapes arranged radially outward and diamond shapes arranged radially centrally.

[0011] In this way, the drag torque is further reduced.

[0012] A further preferred exemplary embodiment of the groove pattern is characterized in that the first friction lining pads at the pad corners have a pad angle of 5 to 125 degrees. Each pad corner includes an interior corner of the pad.

[0013] A further preferred exemplary embodiment of the groove pattern is characterized in that the pad outer edge is rounded along its circumferential contour at all pad corners of the first friction lining pad as well as the second friction lining pad, which has proven to be advantageous with regard to the flow rate around the friction lining pads.

[0014] Another preferred exemplary embodiment of the groove pattern is characterized by a round radius at the corners of the pads of 1 mm or more, which has proven to be sufficient in terms of flow around the friction lining pads.

[0015] Another preferred exemplary embodiment of the groove pattern is characterized in that the first friction lining pads have a width and height with a width-to-height ratio of less than 1.5 for each first friction lining pad. The width-to-height ratio of the first friction lining pads is particularly advantageously less than 1.1. This width-to-height ratio is advantageous for both rotation directions in which the friction plate can rotate.

[0016] Another preferred exemplary embodiment of the groove pattern is characterized in that the first and second friction lining pads all have the same thickness, the thickness of the first friction lining pad being reduced only in the area of ​​the embossed grooves.

[0017] A further preferred exemplary embodiment of the groove pattern is characterized in that the embossed grooves have a smaller width than the dividing grooves and the embossing depth of the embossed grooves corresponds to a maximum of 50 percent of the thickness of the friction lining pad, so that the flow rate through the dividing grooves and the embossed grooves can be very effectively influenced.

[0018] Another preferred exemplary embodiment of the groove pattern is characterized in that the first friction lining pad and the second friction lining pad all represent a friction surface having an inner diameter and an outer diameter, and both all intersections of the dividing grooves with the embossed grooves and all intersections of the dividing grooves with the dividing grooves are located in the friction surface. The friction surface essentially has the shape of an annular area having an inner diameter and an outer diameter. The friction surface is bounded by the friction lining pads and can have size deviations in both the inner diameter and the outer diameter, subject to tolerances. The intersections of the grooves are advantageously located in the friction surface.

[0019] Another preferred exemplary embodiment of the groove pattern is characterized in that the embossed grooves of the first friction lining pads intersect with the dividing grooves defined by the triangular shape of the respective first friction lining pads at an angle of 75 to 90 degrees. A particularly preferred degree measurement is 76.1 degrees. The specified angle range has proven to be very effective with regard to the desired influence of the oil flow in the claimed groove pattern.

[0020] Another preferred exemplary embodiment of the groove pattern is characterized in that the dividing grooves between the second friction lining pads have a larger groove width than the dividing grooves between the first friction lining pads, which is advantageous in terms of cooling and / or lubrication functions when the friction plates are in operation.

[0021] Another preferred exemplary embodiment of the groove pattern is characterized in that the dividing grooves between the second friction lining pads have a larger groove volume than the dividing grooves between the first friction lining pads, which is also advantageous with regard to the cooling and / or lubrication function during operation of the friction plates.

[0022] A further preferred exemplary embodiment of the groove pattern is characterized in that the second friction lining pad has a pad angle at the pad corner of 60 to 150 degrees. In this way, the flow rate through the groove can be specifically adjusted by simple means.

[0023] Another preferred exemplary embodiment of the groove pattern is characterized in that the second friction lining pads have a width and height with a width-to-height ratio for each second friction lining pad of less than 1. A particularly preferred width-to-height ratio of the second friction lining pads is 0.93.

[0024] Another preferred exemplary embodiment of the groove pattern is characterized in that all friction lining pads have the same shape and size, which has proven to be advantageous with regard to the manufacture and assembly of the friction lining pads, the term same shape and size including manufacturing tolerances.

[0025] The present invention also relates to a first friction lining pad and / or a second friction lining pad for the groove pattern as described above. The friction lining pads can be purchased separately.

[0026] Further advantages and advantageous configurations of the invention are the subject of the following drawings and their description. [Brief description of the drawings]

[0027] [Figure 1] Shows the relationship between intake and drag torque [Diagram 2] Showing the object and the improvement points [Diagram 3] FIG. 1 shows the groove design according to the invention, in particular pad 1 [Figure 4] Dimensions of pad 1 with groove design according to the present invention are shown. [Diagram 5] Dimensions of pad 1 with groove design according to the present invention are shown. [Figure 6] Dimensions of pad 1 and pad 2 for groove design according to the present invention are shown. [Figure 7] Dimensions of pad 1 with groove design according to the present invention are shown. [Figure 8] FIG. 1 shows the groove design according to the invention, specifically pad 2 [Figure 9] FIG. 1 shows the dimensions of the pad 2 with the groove design according to the present invention. [Figure 10]FIG. 1 shows the dimensions of the pad 2 with the groove design according to the present invention. [Figure 11] 1 shows dimensions of groove design according to the present invention [Figure 12] 1 shows a further groove design according to the present invention (mirrored) DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Pad 1 (Figs. 3 to 7, 11, 12) Pad angle (Fig. 4(1)) is 5 to 125 degrees (see Fig. 11 for details). The outer edge of the pad is rounded along the circumference, preferably ≥ 1 mm (Figure 5 (2)). Pad 1 design: The central embossing of the embossing groove (Figure 6 (6)) forms a triangular pad surface on the radially outer side and a rectangular (diamond) pad surface in the radial center, none of which is embossed. The ratio of pad width (3) to height (4) is less than 1.5 (preferably 1.1) (FIG. 5). Width of the embossed groove (FIG. 6(6))<width of the dividing groove (FIG. 6(5), FIG. 11), i.e., the pad spacing between immediately adjacent pads 1 or between pads 1 and 2. The maximum embossing depth is half the lining thickness, i.e. maximum half of the non-embossed pad area. The angle (FIG. 6(7)) between the embossed groove (FIG. 6(6)) and the dividing groove (FIG. 6(5)) is between 75 degrees and 90 degrees, and preferably 76.1 degrees. · The intersection (top of Fig. 7(8)) of the embossed groove (Fig. 6(6)) with the dividing groove (Fig. 6(5)) is within (smaller than) the outer diameter (Fig. 7, upper dashed line). The intersection (bottom of Fig. 7(8)) of the dividing groove between the diamond of pad 1 and the directly adjacent pad 2 with the dividing groove is within (smaller than) the inner diameter (Fig. 7, lower dashed line). The groove volume of the inlet groove (Fig. 6(9)) is greater than the groove volume of the outlet groove (Fig. 6(5)).

[0029] Pad 2 (Figures 3, 6, 8 to 11, 12) The pad angle (Figure 9(1)) is 60 to 150 degrees (see Figure 11 for details). The pad outer edge is rounded along the circumference, preferably ≥ 1 mm (Figure 10 (2)) The basic shape of pad 2 is implemented as a pentagonal shape, which is implemented as a combination of a triangular shape and an immediately adjacent rectangular shape (Figures 3, 6, 8 to 11). The ratio of pad width (3) to height (4) is less than 1 (preferably 0.93) (Figure 10)

[0030] Production quality is optimized through pad shape optimization.

[0031] In the open state of the friction system, the texture and edge quality are improved and therefore the drag torque is reduced (especially through the use of embossed grooves instead of cut edges)

[0032] The wear behavior of the pad edges and pad corners over their lifetime is robust. Maintenance of the edge shape (low roundness (1)) leads to robust and consistent hydrodynamic behavior (lubricating wedge) and therefore stable friction characteristics. The application effort of the controls is reduced.

[0033] Optimization of the radial cooling capacity distribution: the groove volume decreases towards the outside (see inside of the groove (9) and outside of the groove (5) or embossing (6)), the groove filling degree (from inside to outside) increases, thus improving the heat transfer from the steel plate to the oil.

[0034] 12 shows a further groove design according to the invention. Compared to the previous representation, this is the result of a reflection, for example, on a radial line.

[0035] In Fig. 1 three Cartesian coordinate diagrams are displayed one above the other. The rotational speed during operation of the wet-running multi-plate clutch 1 with friction elements 15 is plotted in suitable units on the x-axis 20. The volume flow rate in suitable units is plotted on the y-axis 21. The gap filling level in suitable units is plotted on the y-axis 22. The drag torque is plotted in suitable units on the y-axis 23.

[0036] Figure 1 shows how the intake 26 is affected by the delivery volume flow 24 when the supply volume flow 25 is exceeded. From this limit, the gap filling level 26 decreases and the lubricated gap between the plates becomes air-filled. Above this limit, the supply volume flow 25 becomes air-filled. The bottom of Figure 2 shows that the intake 26 occurs at maximum drag torque 27.

[0037] Figure 2 shows how the displacement of the air suction 28 to lower rotational speeds in the drag torque curve 30 is achieved with the claimed friction element 15. The transport behavior of the cooling and / or lubricating media can be improved by the groove pattern shown in Figure 3.

[0038] A groove pattern 10, also referred to as groove design, is shown in Figures 3 to 12. In Figures 1 to 11, the groove pattern 10 comprises first friction lining pads 41, 42, 43 and second friction lining pads 51, 52, 53.

[0039] The groove pattern 10 shown in Fig. 12 comprises the same first friction lining pads 51, 52, 53 as in Fig. 3. However, the groove pattern 10 in Fig. 12 comprises first friction lining pads 61, 62, 63 arranged in a mirror-inverted manner compared to the first friction lining pads 41-43 in Fig. 3. In other respects, the friction lining pads 61-63 correspond to the friction lining pads 41-43.

[0040] 4 shows an enlarged view of the friction lining pad 42. Like the other first friction lining pads 41 and 43, the friction lining pad 42 has a first pad shape that is composed of a triangular shape 44 and a diamond shape 45. In the first friction lining pad 42, an embossed groove 40 is formed between the triangular shape 44 and the diamond shape 45.

[0041] In Fig. 9, the second friction lining pad 52 is shown in an enlarged view. Like the other second friction lining pads 51, 53, the second friction lining pad 52 has a second pad shape, i.e. a pentagonal shape 55 made up of a triangular shape 56 and a rectangular shape 57. The apex of the triangular shape 56 is directed radially outward.

[0042] In figure 3 it can be seen that the first friction lining pads 41-43 and the second friction lining pads 51-53 are glued to the carrier plate 18 to represent the friction plate 19. The first friction lining pads 41-43 and the second friction lining pads 51-53 are arranged and spaced apart from each other so as to form dividing grooves 31-37, the depth of which is limited by the carrier plate 18.

[0043] In contrast to the dividing grooves 31-37, the embossed groove 40 has a smaller depth. The depth of the embossed groove 40 is at most 50 percent of the thickness of the friction lining pad 42. The depth of the dividing grooves 31-37 corresponds to the thickness of the friction lining pads 41-43, 51-53, 61-63.

[0044] Several plates 19 made of steel plates are arranged in a plate pack of a plate clutch. Normally, when a multi-plate clutch is in operation, the assigned steel plate rotates faster than the respective friction plate.

[0045] The pad interior corners 1 of the friction lining pads 42 and 52 are shown in Figures 4 and 9. In Figure 11, the pad interior corners 1 are given individual reference numerals 81-88.

[0046] Pad interior angle 81 is 51.2 degrees. Pad interior angle 82 is 121.3 degrees. Pad interior angle 83 is 110.8 degrees. Pad interior angle 84 is 69.2 degrees. Pad interior angle 85 is 7.5 degrees. Pad interior angle 86 is 61.7 degrees. Pad interior angle 87 is 145.4 degrees. Pad interior angle 88 is 93.8 degrees.

[0047] Using the example of the friction lining pads 42 and 52, Figures 5 and 10 show that all the first friction lining pads and all the second friction lining pads have a round radius 2. The round radius 2 is preferably equal to or greater than 1 mm.

[0048] In addition, the width 3 and height 4 of the friction lining pads 42 and 52 are indicated by double-headed arrows in Figures 5 and 10. The ratio of the corresponding width 3 to height 4 is preferably 1.1 for the first friction lining pads 41-43 and is preferably 0.93 for the second friction lining pads 51-53.

[0049] In Fig. 6, double-headed arrows 5, 6 and 9 indicate the widths of the dividing groove 31, the embossed groove 40 and the dividing groove 37. The dividing groove 37 between the second friction lining pads 52 and 53 opens radially inward and is therefore also referred to as an inlet groove through which oil enters during operation of the multi-plate clutch. Similarly, the grooves 31 and 40 opening radially outward can also be referred to as outlet grooves. The groove width 9 of the inlet groove 37 is greater than the groove widths 5, 6 of the outlet grooves 31, 40.

[0050] 6, a divergence angle 7 is shown by a double-headed arrow between the dividing groove 31 and the embossing groove 40. The divergence angle 7, also referred to as the embossing angle 7, is preferably 76.1 degrees.

[0051] 7, reference lines 75 and 76 indicate the inner and outer diameters of the friction surface 70 represented by the groove pattern 10 of the friction lining pad on the carrier plate 18. It is important that all groove intersections 8, 71-74 lie within the friction surface 70.

[0052] The embossed groove 40 intersects with the dividing groove 32 at an intersection 71. The embossed groove 40 intersects with the dividing groove 34 at an intersection 72. The dividing grooves 32 and 35 intersect at an intersection 73. The dividing grooves 34 and 35 intersect at an intersection 74.

[0053] Node 71 is located radially outward near outer diameter 76, but still within friction surface 70. Similarly, node 74 is located near inner diameter 75, but still within friction surface 70.

[0054] In Fig. 8, three rows are indicated by dashed arcs 11, 12, and 13, and two pad shapes are shown, the first friction lining pads 41-43 and the second friction lining pads 51-53. The second friction lining pads 51-53 represent the first row of the three-row groove pattern 10. The diamond shape of the first friction lining pads 41-43 represents the second or central row of the three-row groove pattern 10. The triangular shape of the first friction lining pads 41-43 represents the third row of the three-row groove pattern 10. [Explanation of symbols]

[0055] 1 Pad inner angle 2 Curve radius 3 Width 4 Height 5 Groove width 6 Groove width 7 Branching angle 8 intersection 9 Groove Width 10 Groove Pattern 11 1st row 12 2nd row 13 3rd row 18 Carrier plate 19 Friction Plate 20x axis 21 y-axis 22 y-axis 23 y-axis 24 Volumetric flow rate 25 Supply volume flow rate 26 Intake 27 Drag Torque 28 Intake 30 Drag torque curve 31 Dividing groove 32 Dividing groove 33 Dividing groove 34 Dividing groove 35 Dividing groove 36 Dividing groove 37 Dividing groove 40 Embossed groove 41 First friction lining pad 42 First friction lining pad 43 First friction lining pad 44 Triangular Shape 51 Second friction lining pad 52 Second friction lining pad 53 Second friction lining pad 55 Pentagonal Shape 56 Triangular Shape 57 Rectangular Shape 61 First friction lining pad 62 First friction lining pad 63 First friction lining pad 70 Friction surface 71 First Intersection 72 Second Intersection 73 Third Intersection 74 Fourth Intersection 75 Inner diameter 76 outer diameter 81 angle 82 angle 83 angle 84 angle 85 angle 86 angle 87 angle 88 angle

Claims

1. A groove pattern (10) for a friction plate, said groove pattern (10) comprising: A first friction lining pad (41-43, 61-63) having a first pad shape; and a second friction lining pad (51-53) having a second pad shape, the groove pattern (10) is annular through an arrangement of a first array of pad shapes arranged radially outwardly to the center and a second array of pad shapes arranged radially inwardly, the arrangement being repeated in the circumferential direction and separated from each other by dividing grooves (31-37); a groove pattern in which the first pad shape and the second pad shape are separated from each other by a dividing groove (33, 34), the first pad shape is designed as a combination of a triangular shape (44) arranged radially outwardly and a diamond shape (45) arranged in the radial center, and an embossed groove (40) is arranged between the triangular shape (44) arranged radially outwardly and the diamond shape (45) arranged in the radial center, the embossed groove having a smaller depth than the dividing grooves (33, 34); A groove pattern, characterized in that the second pad shape is embodied as a pentagonal shape (55) embodied as a combination of a triangular shape (56) and an immediately adjacent rectangular shape (57).

2. A groove pattern according to claim 1, characterized in that said first friction lining pads (41-43, 61-63) have a pad angle (1) at the pad corners of between 5 and 125 degrees.

3. A groove pattern as described in claim 1, characterized in that, when the circumferential dimension is width (3) and the radial dimension is height (4), the first friction lining pads (41-43, 61-63) have a ratio of width (3) to height (4) of less than 1.5 for each first friction lining pad (41-43, 61-63).

4. 2. The groove pattern according to claim 1, characterized in that the first friction lining pads (41-43, 61-63) and the second friction lining pads (51-52) present a friction surface (70) having an inner diameter (75) and an outer diameter (76), and both all intersections (71, 72) of the dividing grooves (32, 34) with the embossed grooves (40) and all intersections (73, 74) of the dividing grooves (32, 34) with the dividing grooves (34, 35) are located within the friction surface (70).

5. 2. A groove pattern according to claim 1, characterized in that the embossed grooves (40) of the first friction lining pads (41-43, 61-63) intersect with the dividing grooves (31, 32) bounded by the triangular shape of each of the first friction lining pads (41-43, 61-61) at an angle of 75 to 90 degrees.

6. 2. A groove pattern according to claim 1, characterized in that the dividing grooves (36, 37) between the second friction lining pads (51-53) have a larger groove width (9) than the dividing grooves (31, 32) between the first friction lining pads (41-43, 61-63).

7. A groove pattern according to claim 1, characterized in that said second friction lining pads (51-53) have a pad angle (1) at the pad corners of between 60 and 150 degrees.

8. A groove pattern as described in claim 1, characterized in that, when the circumferential dimension is width (3) and the radial dimension is height (4), the second friction lining pads (51-53) have a ratio of width (3) to height (4) of less than 1 for each second friction lining pad (51-53).

Images