Annular disc assembly
BACKGROUND OF THE INVENTION 
     This invention relates to an annular disc assembly for transmitting displacement forces. It may be used as a force transmission system in a multiple disc clutch. 
     Known systems comprise discs or plates of spring steel which are provided with notches extending radially from the edges. The radial crosspieces formed between adjacent notches are used to transmit the displacement forces. In order to be able to transmit sufficiently large forces and to withstand the bending stresses occurring in this connection, the lever discs have to be relatively thick. The resistance to deformation resulting therefrom has to be overcome when the displacement forces are transmitted, as a result of which the actuation force required is increased. In addition, the known disc assemblies can break, particularly in the notched regions. 
     It is an object of the invention to provide a disc assembly capable of transmitting large forces. 
     It is another object of the invention to provide a disc assembly which is deformable by relatively small actuating forces. 
     It is a further object of the invention to provide a disc assembly with an improved resistance to breakage. 
     SUMMARY OF THE INVENTION 
     These objects are achieved in a disc assembly comprising an annular disc assembly comprising a plurality of substantially radial spaced spokes joined together by intermediate walls of flexible material. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows an axial centre section through a disc clutch with a disc assembly for transmitting forces according to an embodiment of the invention; 
     FIG. 2 shows the disc assembly in plan; and 
     FIG. 3 shows a section through a detail of the disc assembly on a larger scale. 
    
    
     DETAILED DESCRIPTION 
     The multiple disc clutch shown in FIG. 1 consists of a cup-shaped housing 1 which is sealed by an annular cover 2 is retained in the housing 1 by means of a spring ring 3. In the interior of the housing 1 there is disposed a stack of discs 4 whose discs are supported in teeth alternately on the outer edge or the inner edge. The discs supported in the outer teeth 5 are mounted in the housing 1, whereas the discs supported in the inner teeth 6 are non-rotatably connected to a shaft 7 by means of grooves formed therein. A thrust collar 8 is arranged concentrically about the shaft 7 and acts as a force transmission member via disc assembly 9 on a force application member in the form of a pressure plate 10 abutting against the stack of discs 4. The disc assembly 9 is supported with its outer edge 11 on a force application member in the form of an offset portion 12 of the housing 1 and its inner edge 13 lies on the thrust collar 8. The pressure plate 10 has a bead 14 by which it is supported on the disc assembly 9 between its inner edge 13 and its outer edge 11. 
     As FIGS. 2 and 3 show, the disc assembly 9 comprises rods 15 which are separate from one another, extend radially and are arranged at a distance from one another. The individual rods 15 are connected to one another by intermediate walls 16. The rods 15 advantageously consist of material which is resistant to bending, such as steel, and can have any cross-section. In the embodiment the rods 15 have an oval cross-section. Other typical cross-sections are circular and rectangular. They are embedded in a disc of resilient material, e.g., of rubber or plastic material, which forms the intermediate walls 16. This material is preferably reinforced with textile fabric. 
     The displacement forces for actuating the multiple disc clutch are exerted on the thrust collar 8 in the direction of the arrows shown in FIG. 1. From the ring they are transmitted via the disc assembly 9 to the pressure plate 10 which presses the stack of disc 4 against the cover 2, as a result of which the clutch is engaged. In this connection the displacement forces are transmitted solely by the rods 15 of the disc assembly 9. The task of the intermediate walls 16 is merely to retain the rods 15 in such a way that the intermediate walls 16 can be thin and have practically no resistance to deformation.