CN116745542A - Groove pattern for friction plate - Google Patents

Abstract

The invention relates to a groove pattern for a friction plate, wherein the groove pattern is formed by means of friction linings (11-13) and the friction linings (11-13) have a diamond-shaped configuration, wherein the friction linings (11-13) realize friction surfaces with an inner diameter and an outer diameter. The invention is characterized in that each friction lining (11-13) has an embossing groove which intersects two lining grooves delimited by the respective friction lining at a first intersection point and at a second intersection point, both intersection points being arranged within the friction surface.

Description

Groove pattern for friction plate

Technical Field

The present invention relates to a groove pattern for a friction plate having the features according to the preamble of claim 1.

Background

The grooves or groove patterns, also referred to herein as pad geometries, serve to cool the plate by oil flow even with the shift element closed. The grooves or pattern of grooves chop the oil film, thereby stabilizing the friction value. Thereby achieving the desired friction properties during gear shifting. Improving idle performance and reducing drag torque.

Application field of the invention:

wet plate clutches and plate brakes are widely used in conventional powershift transmissions, new hybrid modules in high-load powertrains, or switchable E-bridges, and are high-performance, high-load components. The need for lower CO2 emissions and improvements in powertrain efficiency in automotive applications are significant. In addition to reducing load-independent losses in the shift element, thermal loading and sufficient cooling must also be taken into account. The groove pattern of the friction plate plays an important role in the friction characteristics, heat balance and efficiency conflict zone. (see FIG. 1)

WO 2016,180,540 a1 discloses an annular wet friction lining having a first set of linearly extending grooves connecting an inner circumference and an outer circumference but not radially extending and intersecting. US 6 293 382 B1 has an additional second groove set, wherein each groove of the second groove set connects two adjacent grooves of the first groove set, respectively.

Disclosure of Invention

The invention is based on the object of minimizing drag losses in a friction plate by means of a suitable groove pattern (see fig. 2) and optimizing the cooling power (see fig. 4).

The object is achieved by a groove pattern having the features according to claim 1.

Thus, the groove pattern for a friction plate according to the invention proposes that the groove pattern is formed by means of friction pads, and that the friction pads have a diamond-shaped configuration, wherein each friction pad has embossed grooves.

The drag torque is further reduced in the manner described.

The diamond-shaped friction pads are fixed at the carrier plate, for example at the carrier metal plate. The carrier sheet basically has the configuration of an annular disk. Radially inside or radially outside, teeth are provided on the carrier plate, which teeth serve to achieve a rotationally fixed connection to the plate carrier. On the radially inner and radially outer sides, the edges at the carrier plate advantageously remain free of friction linings. Thus, compensation of tolerances in the size and/or configuration of the friction lining can be achieved when fixed at the carrier plate. Furthermore, the friction linings are advantageously evenly spaced from one another in the circumferential direction. By the spacing between the friction pads in the circumferential direction from each other, grooves between the friction pads are created. The grooves are hereinafter referred to as pad grooves. The pad grooves extend obliquely to the radial direction due to the diamond-shaped configuration of the friction pad. In relation to the direction of rotation of the friction plate, a blocking or pumping effect is produced, wherein the steel plate rotates faster than the friction plate. These two effects are described in detail in the following description of the drawings. The oil flow between the steel sheet and the friction plate from the radially inner side towards the radially outer side can be optimized in particular with respect to the cooling power by means of the embossing grooves in the friction lining. Particularly advantageously, the blocking effect resulting from the blocking effect can be most effectively altered by the co-action between the pad grooves and the embossing grooves in combination with the diamond-shaped friction pads.

The friction pad realizes a friction surface having an inner diameter and an outer diameter. The pad grooves are realized by the spacing between the friction pads. The friction surface has the configuration of a torus with an inner diameter and an outer diameter. The friction surfaces are delimited by friction linings, so that dimensional deviations can be made with tolerance at the inner diameter and at the outer diameter. According to an important aspect of the invention, both intersections of the embossed groove of each friction pad with the pad groove delimited by the friction pad are always provided within the friction plate, i.e. radially between the inner and outer diameter of the friction face.

A preferred embodiment of the groove pattern is characterized in that the pad inner angle in the pad corner has a degree value between forty and one hundred forty-five degrees. Surrounding the interior corners of the pad in each pad corner. Because of the diamond-shaped configuration of the friction pads, each friction pad includes two opposing interior angles greater than ninety degrees and two additional opposing interior angles less than ninety degrees. This involves the size range proposed. Two of the interior angles are preferably between forty and fifty degrees. The two further internal angles are preferably between one hundred twenty-five degrees and one hundred forty-five degrees.

Another preferred embodiment of the groove pattern is characterized in that all pad corners are rounded along their circumferential contour. This has proved to be advantageous with regard to the circulation of the friction lining.

Another preferred embodiment of the groove pattern is characterized in that the radius of the rounding in the corners of the pad is greater than or equal to one millimeter. This proves to be sufficient with respect to the circulation of the friction lining.

Another preferred embodiment of the groove pattern is characterized in that the friction pads have a width to height ratio of less than two for each friction pad. The width to height ratio of the friction pad is preferably between 1.5 and 1.7. The width to height ratio is advantageously adapted to both rotational directions in which the friction plate can rotate.

Another preferred embodiment of the groove pattern is characterized in that between two adjacent friction linings a pad groove having a groove width is provided, respectively, which is smaller than the groove width of the embossed groove in the friction lining. The width of the pad grooves is defined by the spacing of the diamond shaped friction pads relative to each other. The smaller groove width of the pad groove is particularly advantageous as a pad groove preferably has a greater groove depth than the embossed groove.

Another preferred embodiment of the slot pattern is characterized in that the branching angle between the pad slot and the imprint slot is between ninety degrees and one hundred degrees. A particularly preferred branching angle between the pad slot and the imprint slot is 90.4 degrees. By the angular range given, the embossing grooves extend substantially transversely to the pad grooves. This has proved to be particularly effective in terms of the desired influence of the oil flow in the claimed groove pattern.

Another preferred embodiment of the groove pattern is characterized in that the groove depth of the embossing grooves corresponds to a maximum of fifty percent of the thickness of the friction lining. This has proven to be advantageous in terms of manufacturing and securing the friction pad.

Another preferred embodiment of the groove pattern is characterized in that all friction pads have the same configuration and size. This has also proven to be advantageous in connection with the manufacture and installation of the friction lining. The expression "identical configuration and dimensions" includes manufacturing tolerances.

The invention furthermore relates to a friction lining for the groove pattern described hereinabove. The friction pads may be individually transacted.

Drawings

Other advantages and advantageous embodiments of the invention are the subject matter of the following figures and their description.

The details are shown:

fig. 1 shows the relationship: intake and drag torque

FIG. 2 shows the object and improvement

FIG. 3 shows the transport and blocking actions

Fig. 4 shows cooling power

FIG. 5 shows a groove design according to the invention

FIG. 6 shows the dimensions of a slot design according to the invention

FIG. 7 shows the dimensions of a slot design according to the invention

FIG. 8 shows the dimensions of a slot design according to the invention

FIG. 9 shows a pad of groove design according to the present invention

Fig. 10 shows a view similar to that in fig. 3A, illustrating that the intersection point between the embossing groove and the pad groove is always provided within the friction surface.

Detailed Description

● The angle (1) in FIG. 6 is between 40 and 145 degrees (see FIG. 9 for details)

● The outer edge of the pad is rounded along the circumference, preferably 1mm or more (see FIG. 7 (2))

● The double row design when the middle nip is considered yields almost the same pad surface in the triangular shape for the inner and outer rows, irrespective of the basic geometry of the nip: the pad is formed into diamond shape

● The ratio of the width (3) to the height (4) of the pad is less than 2 (preferably 1.5 to 1.7) (see fig. 7)

● The width of the embossed portion (5) is greater than the width of the groove (6) (see FIG. 8)

● The ratio of groove angle to embossing angle (7) is between 90 degrees and 100 degrees, preferably 90.4 degrees (see fig. 8)

Optimizing the production quality by optimizing the pad geometry.

The fibre and edge quality improves so that in the disconnected state of the friction system the drag torque is reduced, for example by means of a groove impression.

Pad edges and pad corners robust friction behavior over the lifetime. Maintenance of the edge geometry (small rounding (1)) leads to a robust, constant hydrodynamic behavior (oil wedge) and thus to stable friction properties, and the application effort for regulation is reduced.

By means of a further preferred embodiment of the invention, the oil film is rapidly led out, wherein the branching angle (7) is between 90 ° and 100 °, preferably 90.4 °.

By means of the angular position of the grooves, it is possible to achieve a delivery effect (fig. 3A) or a blocking effect (fig. 3B) of the oil, depending on the relative rotation direction of the steel sheet with respect to the friction plate. Depending on the relative rotational direction between the friction plate and the steel plate, the cooling power can thus be changed in dependence on the application (see fig. 4). By means of the pad embossing (fig. 5 "embossing grooves"), the effect can be formed arbitrarily (see fig. 8: embossing depth, width (5), angle (7)) and optimized for the respective application.

In fig. 1, three cartesian coordinate system diagrams are shown one above the other. The rotational speed of the wet-running plate clutch 1 with the friction element 15 is plotted on the x-axis 20 in each case in suitable units. The volumetric flow is plotted in suitable units on the y-axis 21. The gap filling is plotted in appropriate units on the y-axis 22. Drag torque is plotted in appropriate units on the y-axis 23.

In fig. 1 it is illustrated how the intake air 26 is carried out via the delivered volumetric flow 24 if the intake air exceeds the supplied volumetric flow 25. Starting from the limit value, the gap filling 26 decreases and the lubrication gap between the sheets contains air. Starting from said limit value, the supplied volumetric flow 25 contains air. As can be seen in fig. 2 below, the intake air 26 occurs with a maximum drag torque 27.

Fig. 2 shows how the movement of the intake air 28 in the drag torque curve 30 towards low rotational speeds is achieved by means of the loaded friction element 15. By means of the groove pattern shown in fig. 3, the conveying action of the cooling medium and/or the lubricating medium can be improved.

Fig. 3 includes fig. 3A and 3B. In fig. 3A and 3B a groove pattern 10 according to the invention is shown, which groove pattern is also referred to as groove design. The groove pattern 10 includes friction pads 11 to 13;14 to 16, which are arranged on the carrier plate 18. Having friction pads 11 to 13; the carrier plates 18 of 14 to 16 are referred to as friction plates 19.

Friction pads 11 to 13;14 to 16 all have a diamond-shaped configuration with rounded corners. In the circumferential direction, friction pads 11 to 13;14 to 16 are spaced apart from each other such that there are two adjacent friction pads 12, 13; 14. between 15, respectively, a pad groove 8 is created. The depth of the pad slot 8 is bounded by the carrier sheet 18. The pad groove 8 extends obliquely to the radial direction.

Further, each friction pad 11 to 13;14 to 16 each comprise an embossing slot 9. The embossing grooves 9 extend transversely to the pad grooves 8. Further, the pad groove 8 has a greater groove depth than the imprint groove 9. The embossing grooves 9 have a groove depth of at most friction linings 11 to 13; fifty percent of the thickness of 14 to 16. The groove depth of the pad groove 8 corresponds to the friction pads 11 to 13;14 to 16.

In the plate clutch, a plurality of friction plates 19 having steel plates are provided as a plate group. In fig. 3A and 3B by arrow 60;70 indicates the direction of rotation during operation of the friction plate 19. Here, the following conditions apply: the associated steel plates rotate faster than the associated friction plates 19, respectively. Through arrows 61 to 64;71 to 74 indicate forces acting in operation, which are generated by the oil flow between the friction plate 19 and the steel plate from the radially inner side towards the radially outer side.

Arrow 61;71 illustrate the centrifugal force. Arrow 62;72 illustrates the flow through the pad slot 8, which passes through the friction pads 11 to 13;14 to 16 with pad interior angle and direction of rotation 60;70 in relation to force, said force passing through arrow 62; 72.

Through arrow 63;73 in fig. 3A and 3B illustrate the forces caused by the relative movement between the steel plate and the friction plate 19. Through arrow 64;74 indicates the forces 61 to 63;71 to 73.

Fig. 3A illustrates the blocking effect which is created by the friction pads 11 to 13 when the friction plate 19 rotates slower than the associated steel plate in the direction of rotation 60. Fig. 3B illustrates the pumping action that occurs through the friction pads 14-16 when the friction plate 19 rotates slower than the associated steel plate in the direction of rotation 70.

A bar graph having a y-axis 40 and columns 41 to 44 is shown in fig. 4. The cooling power in kilowatts is plotted on the y-axis 40. The columns 41 to 44 show the cooling power for different sized volume flows which can be achieved by means of the slot pattern 10 in fig. 3A and 3B.

Columns 41 and 42 illustrate the relatively low volumetric flow of oil. The columns 43, 44 illustrate the very high volumetric flow of oil. Here, the columns 41, 43 are associated with pumping action in fig. 3A. The posts 42, 44 are associated with a blocking action in fig. 3B.

By pumping action, a higher cooling power is obtained not only in low volume flows but also in high volume flows. However, the cooling power does not change as strongly in high volume flows as in low volume flows, as can be seen in fig. 4. The blocking effect can be reduced or altered depending on the application via the embodiment of the embossing slot or via the cross section, i.e. the width and depth of the embossing slot. The larger the cross section, the more oil can flow out through the embossing grooves.

In fig. 5, the friction linings 11 to 13 are shown rounded at their pad corners 31 to 34. In fig. 7, the radius of the rounding is denoted by 2, which is substantially the same in all the pad corners 31 to 34. The radius 2 of the rounding is advantageously greater than or equal to one millimeter.

The internal pad angle 1 at the friction lining 12 is indicated by the double arrow in fig. 6. The pad interior angle 1 is between 40 degrees and one hundred forty-five degrees. By the central arrangement of the embossing grooves 9 in the friction lining 12, a double-row groove design is produced with identical lining surfaces on the radially inner and radially outer sides. The same pad faces each have a triangular shape due to the diamond-shaped configuration of the friction pad 12.

The width of the friction lining 12 is indicated in fig. 7 by the double arrow 3. The height of the friction lining 12 is indicated by double arrow 4. The ratio of width 3 to height 4 is preferably less than two for all friction pads. The ratio between width 3 and height 4 is advantageously for all friction linings 11 to 13 of the groove pattern 10; 14 to 16 are preferably between 1.5 and 1.7.

Auxiliary lines for dimensioning are drawn at the friction lining 12 in fig. 6 and 7. There is a spacing partially between the auxiliary line and the friction pad 12. The spacing should be illustrative of tolerances that may exist at the friction pad 12 due to manufacturing.

The groove width of the embossing groove 9 is indicated by the double arrow 5 in fig. 8. The groove width of the pad groove 8 between the friction pads 12 and 13 is indicated by double arrow 6. The branching angle between the pad slot 8 and the embossing slot 9 is indicated by the double arrow 7.

The branching angle 7 between the pad slot 8 and the imprint slot 9 is advantageously between ninety degrees and one hundred degrees, preferably 90.4 degrees, in the complete slot pattern 10.

The inner corners of the friction pad 12 are indicated in fig. 9 by double arrows 51 to 54. The number of degrees of the pad inner angles 51 to 54 is 132 in the order mentioned; 44.5;142;41.6.

in fig. 10, the friction plate 19 in fig. 3A is shown by means of auxiliary lines, which illustrate that the friction linings 11 to 13 realize the friction surface 80. The friction surface 80 is delimited radially inward by an inner diameter 83 and radially outward by an outer diameter 84. Here, manufacturing-dependent tolerances can occur.

It is however important that the intersection 81, 82 between the embossing groove 9 of the friction lining 12 and the two lining grooves 8 and 78 delimited by the friction lining 12 is arranged within the friction surface 80.

Description of the reference numerals

1. Interior corner of pad

2. Radius of radius

3. Width of (L)

4. Height of (1)

5. Groove width

6. Groove width

7. Branch angle

8. Pad groove

9. Embossing groove

10 groove pattern

11 Friction pad

12. Friction lining

13. Friction lining

14. Friction lining

15. Friction lining

16. Friction lining

18. Carrier sheet

19. Friction plate

20 X-axis

21 y-axis

22 y-axis

23 y-axis

24. Volumetric flow of transport

25. Volumetric flow of feed

26. Air intake

27. Drag torque

28. Air intake

30. Drag torque profile

31. Pad corner

32. Pad corner

33. Pad corner

34. Pad corner

40 y-axis

41. Column

42. Column

43. Column

44. Column

51. Interior corner of pad

52. Interior corner of pad

53. Interior corner of pad

54. Interior corner of pad

60. Direction of rotation

61. Arrows

62. Arrows

63. Arrows

64. Arrows

70. Direction of rotation

71. Arrows

72. Arrows

73. Arrows

74. Arrows

78. Pad groove

80. Friction surface

81. First intersection point

82. Second intersection point

83. Inner diameter of

84. An outer diameter.

Claims (10)

1. A groove pattern (10) for a friction disk, wherein the groove pattern (10) is formed by means of a friction lining (11-13; 14-16) and the friction lining (11-13; 14-16) has a diamond-shaped configuration, wherein the friction lining (11-13; 14-16) realizes a friction surface (80) with an inner diameter (83) and an outer diameter (84),

it is characterized in that the method comprises the steps of,

each friction pad (11-13; 14-16) has an embossing groove (9) which intersects two pad grooves (8; 78) delimited by the respective friction pad at a first intersection point (81) and a second intersection point (82), both of which are arranged within the friction surface (80).

2. The pattern of grooves of claim 1,

it is characterized in that the method comprises the steps of,

the pad inside angle (1) in the pad corner has a degree value between 40 degrees and 145 degrees.

3. The pattern of grooves of any preceding claim,

it is characterized in that the method comprises the steps of,

all pad corners are rounded along their circumferential profile.

4. The pattern of grooves of any preceding claim,

it is characterized in that the method comprises the steps of,

the radius of rounding (2) in the pad corners is greater than or equal to one millimeter.

5. The pattern of grooves of any preceding claim,

it is characterized in that the method comprises the steps of,

the friction pads (11-16) have a width (3) and a height (4) having a width (3) to height (4) ratio of less than 2 for each friction pad (11-16).

6. The pattern of grooves of any preceding claim,

it is characterized in that the method comprises the steps of,

between two adjacent friction linings (11-16) there are respectively arranged a lining groove (8; 78) having a groove width (5) which is smaller than the groove width (6) of the embossing groove (9) in the friction lining (11-16).

7. The pattern of slots as claimed in claim 6,

it is characterized in that the method comprises the steps of,

the branching angle (7) between the pad groove (8; 78) and the embossing groove (9) is between 90 degrees and 100 degrees.

8. The pattern of grooves of any preceding claim,

it is characterized in that the method comprises the steps of,

the embossing depth of the embossing groove (9) corresponds to a maximum fifty percent of the thickness of the friction lining (11-16).

9. The pattern of grooves of any preceding claim,

it is characterized in that the method comprises the steps of,

all friction pads (11-16) have the same configuration and size.

10. A friction pad (11-16) for a groove pattern (10) according to any of the preceding claims.