BRIEF DESCRIPTION OF THE DRAWINGS
To illustrate the invention, the description and figures with exemplary embodiments are attached, wherein:
FIG. 1 is a schematic longitudinal section of a multi-disk brake with alternate axial and radial cooling oil feeding, and
FIG. 2 is a multi-disk brake according to FIG. 1 in which, however, a circulatory flow of cooling oil about the exterior disk is additionally implemented.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 accordingly shows a multi-disk brake 1, according to a first embodiment of the invention. This multi-disk brake 1 is configured, by way of example, as a shifting member of an automatic transmission and comprises, first of all, an inner disk carrier 4 carrying an internal disk with the carrier being connected to a rotatable component of the automatic transmission, the component not being illustrated here. Furthermore, the multi-disk brake 1 has an outer disk carrier 6 carrying an external disk 5, the carrier being non-rotatably connected to the housing 12 of the automatic transmission. The internal disks 3 and the external disks 5 are alternately disposed axially adjacent to each other and, together with two end disks 8 and 9, form a clutch pack 14. A piston 10 of a pressurant-actuated piston-cylinder arrangement can apply an axially actuating force, that engages the multi-disk brake 1, on one end disk 9 while the opposite end disk 8 is firmly connected to the housing 12 and forms an axial abutment for the entire clutch pack 14. A disk spring 11, disposed in the region of the end disk 9 on the piston side, ensures that the piston 10 is pushed back when it is not actuated.
Furthermore, the internal disks 3 and the external disks 5 each are provided with friction linings, wherein the friction linings 7, 7′ are respectively disposed to point in the same axial direction. The end disks 8 and 9 are constructed without friction linings.
This multi-disk brake 1 is cooled by a cooling oil current by means of cooling oil 13, which is very effectively directed between the individual internal disks 3 and the external disks 5 as well as the friction linings 7, 7′ thereof. For this purpose, the cooling oil 13 is first supplied under pressure to the end disk 8 forming the axial abutment, whereby the cooling oil 13 flows into the clutch pack 14 through the axial inflow orifice 25 of the end disk.
The cooling oil 13 flows from the inflow orifice 25 in the end disk 8 through an axial orifice 16 in the exterior disk 5, close to the end disk, into a radial groove 19 in the friction lining 7 of the same. The cooling oil 13 first flows within this radial groove 19 radially inward in the direction of the inner disk carrier 4. In the region of the radial end 17 of the internal disk 3, the end being close to the inner disk carrier, an axial orifice 15 is provided, through which the cooling oil 13 flows. From there, the cooling oil 13 reaches a radial groove 20 in the friction lining 7′ of the internal disk 3, so that the oil can continue to flow radially outward in the direction of the outer disk carrier 6.
At the end 18 close to the outer disk carrier, the next external disk 5 likewise comprises an axial orifice 16, through which the cooling oil 13 can then enter the radial groove 19 in the friction lining 7 of this external disk 5.
The current of the cooling oil 13 is generated by the cooling oil pressure on the inlet side as well as by a pump effect of the grooved and moving internal disks 3. Since the cooling oil 13, as mentioned above, flows with pressure into the clutch pack 14, this cooling oil current is also maintained for cooling the multi-disk brake 1 when the internal disks 3 are fully braked.
After the aforementioned alternate axial and radial flow through the clutch pack 14, the cooling oil 13 reaches the end disk 9 on the piston side and the cooling oil 13 is then discharged from the clutch pack via at least one axial discharge orifice 26 in the end disk.
The axial orifices 15 or 16, in the internal disks 3 and the external disks 5 can be disposed alternately in any arbitrary manner, however, it is preferred if these orifices 15 or 16 are provided radially close to the inner disk carrier 4 or outer disk carrier 5 associated with the respective disk.
FIG. 1 furthermore shows that the internal disks 3 and the external disks 5 at the respective radial end thereof that is removed from the carrier, have an annular sealing segment 21 or 22, which is preferably made of the material of the friction lining 7, 7′. This sealing segment 21 or 22 prevents radial loss of cooling oil in the region in which the cooling oil current is deflected in the clutch pack 14.
Since the disks 3 and 5, used in the exemplary embodiment according to FIG. 1, are such that they carry a friction lining 7 or 7′ only on one side, in the present case pointing to the left, another seal 27 is provided between the end disk 8 and the axially next external disk 5 to prevent leakage of the cooling oil 13 in the transfer region and the seal being disposed or configured either on this end disk 8 or on this external disk 5.
The second variant of an inventive multi-disk brake 2, shown according to FIG. 2, differs from the multi-disk brake 1 according to FIG. 1 only in that the cooling oil 13 flows through the clutch pack 14 not only alternately axially and radially, but also that a circulatory flow about the external disks 5 or about substantial radial and axial sections of the same is produced. This cooling oil current, which is advantageous for fast heat dissipation, is achieved by additional axial orifices 24 in the external disks 5 in the region of the radial ends thereof removed from the disk carrier.
This circulatory current alternately can be produced on the internal disks 3 if these instead of the external disks 5 have the axial orifices in the region of the radially inner and outer ends thereof.
In order to facilitate axial flow through the clutch pack 14 of the multi-disk brake 2 according to FIG. 2, the axial orifices 15, 16 or 24, in the internal disks 3 or in the external disks 5, can have different diameters and/or different flow resistance values. In this way, the design allows a predefined adjustment of the volume flow of the cooling oil, in the axial direction, through the clutch pack 14 and of the circulatory volume flow about the disks 3 and/or 5.
REFERENCE NUMBERS
1 Multi-disk brake, multi-disk clutch
2 Multi-disk brake, multi-disk clutch
3 Internal disk
4 Inner disk carrier
5 External disk
6 Outer disk carrier
7 Friction lining
7′ Friction lining
8 End disk on inflow side
9 End disk on piston side
10 Piston
11 Disk spring
12 Housing
13 Cooling oil
14 Clutch pack
15 Axial orifice in internal disk
16 Axial orifice in external disk
17 Radial end of an internal disk
18 Radial end of an external disk
19 Radial groove in external disk
20 Radial groove in internal disk
21 Sealing segment
22 Sealing segment
23 Synchronizing teeth element
24 Axial orifice
25 Inflow opening in end disk on inflow side
26 Discharge opening in end disk on piston side
Patent Application
20080006501
