Abstract:
A cone ring transmission, especially for motor vehicles with a front, transverse drive is proposed, having two cones in opposed alignment to one another, rotating on two shafts, the cones being, namely a primary cone and a secondary cone, with an adjustment ring engaging both cones therebetween, the ring contacting one cone and circumferentially encompassing the other cone, with a mechanism to provide ratio adjustment for the adjustment ring, having an arrangement which binds the output drive shaft, i.e. the shaft of the secondary cone with a differential of the motor vehicle and with a start-up element, which binds one of the cones with the motor of the motor vehicle, whereby the torque from the output drive shaft is transmitted to a differential by way of a gear train.

Description:
This application claims priority from German Application Serial No. 10 2004 003 691.8 filed Jan. 24, 2004. 
   FIELD OF THE INVENTION 
   The present invention concerns a cone ring transmission, especially for a front, transverse installation in a motor vehicle, which transmission possesses two rotating cones, which are oppositely aligned to each other, on two shafts, which shafts rotated in a counter sense to one another, the said rotating cones being a primary cone and a secondary cone. 
   BACKGROUND OF THE INVENTION 
   EP A 878 641 discloses a stepless cone ring transmission, which has two frictionally conical rotors, located at a radially separating distance from each other and which are relatively oppositely aligned to one another and have the same conical angle. Between the conical frictional rotors is placed a frictional ring, which fully occupies the space between the two rotors. The ring circumferentially encompasses one of the conical rotors and is confined in a cage. 
   The cage consists of a framing, which is constructed from two transverse beams and two parallel axles in the interior. An adjustment bridge is placed on the axles, which bridge is furnished with guide rollers, which engage the frictional ring on both sides, in order to give this ring the necessary axial alignment. The cage is again pivotal on a vertical axle, whereby this vertical axle lies in a specified plane which also passes through the axles of the frictional conical rotors. If the cage is angularly moved a few degrees, then the frictional drive causes an axial displacement of the adjustment bridge, and hence, a change in the ratio relationships of the conical rotors. 
   Such a cone ring transmission adapts itself, in accord with this disclosure, especially for installation in motor vehicles, and indeed even for front-end as well as rear drive. 
   The purpose of the present invention is, to create a cone ring transmission, which has such a small requirement for installation space, that it is suitable both for front as well as rear installation in a motor vehicle. In addition to this, the invented transmission is to exhibit an optimal degree of efficiency. 
   SUMMARY OF THE INVENTION 
   Accordingly, a cone ring transmission, especially for a transverse, front installation in a motor vehicle is proposed, with two cones, oppositely aligned to one another and each mounted on a respective shaft, wherein one is designated as a primary cone, and the other as a secondary cone. An adjustment ring is provided, which stands in engagement with the two cones by being interposed therebetween and circumferentially encompassing one cone. The ring is provided with an axial displacement means for rotational speed ratio adjustment. Further, another arrangement connects the output shaft, that is, the shaft of the secondary cone, with a differential of the motor vehicle and with a start-up element. The start-up element binds one of the cones with the motor of the vehicle, whereby the torque from the output shaft  7 , i.e., the shaft  7  of the secondary cone, is transmitted to the differential  9  of the motor vehicle by means of a gear train, so that no chain drive is required. 
   In this way, the gearing of a planetary gear set and/or an auxiliary gear train can include a reverse shifting stage, that is to say, a direction of rotation reversal. This is accomplished by an appropriate shifting mechanism (for instance, this shifting mechanism being a releasable connection with the housing of an element of the planetary gear set and/or of the auxiliary gear train, or of further means to carry out this purpose). Where forward motion is concerned, it is possible that appropriate shifting elements can be employed, such as, for example, a dog clutch, synchronization or disk clutches. 
   For an additional embodiment, provision has been made, that the torque from the output shaft, that is, the shaft of the secondary cone, can be transmitted to the differential by means of a chain drive, in which case, between the chain drive and the differential, in the direction of power flow, a planetary gear set and/or an auxiliary gear train can be interposed. 
   In accord with the invention, the planetary gear set can be designed as a plus or minus set. The secondary cone can be installed in the motor vehicle, in one development of the invention, directly underneath the primary cone, or be offset therefrom. In an alternative arrangement, the primary cone can be installed underneath the secondary cone or again offset therefrom. 
   The adjustment ring can circumferentially encompass either the primary cone or the secondary cone, whereby, however, experience has shown that it is of advantage if the adjustment ring encircles that cone, which, in accord with the installation is placed higher in the motor space, since, when so placed, it is free from contamination in the oil sump. 
   Further within the confines of the invention, an improvement can be provided, in that the axle, which runs through the center point of the circle formed by the adjustment ring and perpendicular to the plane extending through the adjustment ring, can be operationally aligned at an angle α to the shaft of the cone. 
   As a start-up element, a dry clutch or a wet disk clutch can be installed, whereby the start-up element can be provided with a torsion damper. 
   In order to reduce the required installation space, it is possible, that within the interior of the motor cavity, which the adjustment ring needs for its ratio displacements, an aggregate for the motor or the cone transmission can be furnished. This aggregate can consist of, for example, a heat exchanger, a shifting mechanism for ratio selection, or an activation agent for the start-up element. 
   The installation space, in accord with the invention, can be further reduced, in that those components, which are necessary for shifting into the reverse gear, can be placed inside of the secondary cone. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will now be described, by way of example, with reference to the accompanying drawings in which: 
       FIG. 1  is a diagrammatic representation of an embodiment of a cone ring transmission; 
       FIG. 2  is a diagrammatic representation of an embodiment of a cone ring transmission including a planetary gear set and an adjustment ring encircling a secondary cone; 
       FIG. 3  is a diagrammatic representation of an embodiment of a cone ring transmission including a planetary gear set and an adjustment ring encircling a primary cone; 
       FIG. 4  is a diagrammatic representation of an embodiment of a cone ring transmission including an auxiliary gear train and an adjustment ring encompassing a secondary cone; 
       FIG. 5  is a diagrammatic representation of a second embodiment of a cone ring transmission including an auxiliary gear train and an adjustment ring encompassing a secondary cone; 
       FIG. 6  is a diagrammatic representation of another embodiment of a cone ring transmission including a planetary gear set and an adjustment ring encircling a secondary cone; 
       FIG. 7  is a diagrammatic representation of another embodiment of a cone ring transmission including a planetary gear set and an adjustment ring encircling a primary cone; 
       FIG. 8  is a diagrammatic representation of yet another embodiment of a cone ring transmission including a planetary gear set and an adjustment ring encircling a secondary cone; 
       FIG. 9  is a diagrammatic representation of a further embodiment of a cone ring transmission including a planetary gear set and an adjustment ring encircling a secondary cone; 
       FIG. 10  is a diagrammatic representation of a further embodiment of a cone ring transmission including an auxiliary gear train; 
       FIG. 11  is a diagrammatic representation of yet another embodiment of a cone ring transmission including a chain drive and an adjustment ring encircling a secondary cone; 
       FIG. 12  is a diagrammatic representation of an additional embodiment of a cone ring transmission, having a planetary gear set with a change of direction means; and 
       FIG. 13  is a diagrammatic representation of yet another embodiment of a cone ring transmission, having a planetary gear set with a change of direction means. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In the embodiment shown in  FIG. 1 , the secondary cone  6  is placed, according to the installation of the cone ring transmission, above the primary cone  4 . The gear arrangement possesses an auxiliary gear train  10  which is placed on the shaft  7  of the secondary cone  6 , whereby the auxiliary gear train  10  is in connection through a sprocket  12  and a chain  13  with a sprocket  11  on the shaft  5  of the primary cone  4 . This is an arrangement in which shifting into reverse is possible. Further, on the shaft  7  of the secondary cone  6  is located a gear  14 , which, coacting with a gear  15 , engages the differential  9 . The start-up element  2 , in accord with  FIG. 1 , is a dry clutch, which is provided with a torsion damper. 
   In the case of the embodiment as shown in  FIG. 2 , the secondary cone  6 , in accord with the installation of the cone ring transmission in the motor vehicle, is placed above the primary cone  4  and the adjustment ring  8  encircles the secondary cone  6 . The gear arrangement includes a planetary gear set  3 , which is placed on the shaft  7  of the secondary cone  6  and is provided with an arrangement  22  for the reversal of the direction of rotation. Advantageously, for effecting the reversal of direction, an element of the planetary gear set  3  is affixed to the housing. In this situation, the sun gear of the planetary gear set  3  is mounted to be rotatably affixed to the shaft  7 . The planetary cage is connected to a gear  14 , which engages itself with the gear  15  of the differential  9 . The start-up element  2  is a dry clutch, which is provided with a torsion damper. The transmission in  FIG. 3 , differentiates itself from the transmission depicted in  FIG. 2 , in that the adjustment ring  8  encircles the primary cone  4 . 
   The transmission in  FIG. 3 , differentiates itself from the transmission depicted in  FIG. 2 , in that the adjustment ring  8  encircles the secondary cone  6 . 
   In the case of the embodiment shown in  FIG. 4 , the secondary cone  6 , in accord with the installation of the cone ring transmission in the motor vehicle, is placed above the primary cone  4 , whereby the adjustment ring  8  circumferentially encompasses the secondary cone  6 . An auxiliary gear train  10  is again provided and is placed on the shaft  7  of the secondary cone  6 . In this case, for forward travel, the auxiliary gear train  10  stands in engagement with a first gear  14  which meshes with a gear  15  of the differential  9 . For reverse travel, the auxiliary gear train  10 , which is driven by means of a shaft in gear  23 , engages itself with the gear  15  of the differential  9 . In this embodiment the start-up element  2 ′ is a wet disk clutch, which is provided with a torsion damper and connected with an electromechanical activation. 
   The transmission illustrated in  FIG. 5 , differentiates itself from the transmission of  FIG. 4 , in that the axis A which penetrates the center point of the circle formed by the adjustment ring  8 , and which axis is perpendicular to the plane defined by the adjustment ring  8 , runs at an angle α to the axis of the shaft  7  of the cone  6 . 
   In  FIG. 6  we are shown a transmission, wherein the secondary cone  6 , in accord with the installation in the motor vehicle, is above the primary cone  4  and offset to one side thereof, whereby the adjustment ring  8  circumferentially encircles the secondary cone  6 . In addition, the gearing has a gear  16 , which is rotatably affixed to the shaft  7  of the secondary cone  6 . The gear  16  further engages itself with an element of the planetary gear set  3 , preferably with the cage, advantageously by means of a gear  19 . An additional element of the planetary gear set  3 , advantageously the sun gear, is rotatably affixed with the shaft of the differential  9 . A reverse of the direction of rotation is accomplished advantageously by the optional coupling of an element of the planetary gear set to the housing. In accord with the invention, the adjustment ring  8 , can circumferentially encompass the primary cone instead of the secondary cone. This configuration is the object of  FIG. 7 . 
   In the embodiment shown in  FIG. 8 , the secondary cone  6 , in accord with the installation of the cone ring transmission in the motor vehicle, is advantageously placed above the primary cone  4  and laterally offset therefrom, whereby the adjustment ring  8  circumferentially encompasses the secondary cone  6  and the axis A which penetrates the center point of the circle formed by the adjustment ring  8 , and which axis is perpendicular to the plane established by the adjustment ring  8 , runs at an angle α to the axis of the shaft  7  of the cone  6 . The arrangement of the gearing includes a planetary gear set  3 , the sun gear of which is rotatably affixed to the shaft  7  of the secondary cone  6 . On the power take-off side, advantageously, the cage of the planetary gear set  3  is connected with a gear rotatably affixed also to the shaft  7 , which engages with a gear  15  of the differential  9 . For the start-up element  2 , a dry clutch is provided, which is advantageously provided with a torsion damper. 
   The embodiment shown in  FIG. 9  differentiates itself from the operational method of  FIG. 8 , in that, as a start-up element  2 ′, a wet disk clutch is provided. 
   In  FIG. 10 , an invented transmission is shown, wherein the secondary cone  6 , in accord with the installation of the cone ring transmission in the motor vehicle, is to be found above the primary cone  4  and laterally offset therefrom. In this case, the adjustment ring  8  circumferentially encompasses the secondary cone  6 . The gear arrangement of this embodiment has an auxiliary gear train  10 , which is placed on the shaft  7  of the secondary cone  6 . In this case, for a forward speed shift, a first gear  14  of the auxiliary gear train  10  engages itself with the first gear  15  of the differential  9 . To achieve a reverse shift, a sprocket  20  of the auxiliary gear train  10  connects through a chain  13  with a sprocket  21  of the differential  9 . As a start-up element  2 ′, a wet disk clutch is provided, which is advantageously provided with a torsion damper and with an electromechanical activation. 
   In  FIG. 11  is shown an embodiment example, wherein the secondary cone  6 , in accord with the installation of the cone ring transmission in the motor vehicle, is placed advantageously above and laterally offset from the primary cone  4 , whereby the adjustment ring  8  circumferentially encompasses the secondary cone  6  and for the transmission of the torque to the differential, a chain drive is provided. In this case, on the shaft  7  of the secondary cone  6 , a sprocket  16  is placed, which, by means of a chain  13  stands in communication with a sprocket  17  of an auxiliary gear train  10 . For forward movement, auxiliary gear train  10  connects, through a gear  14  with a gear  15  of the differential  9 , while for reverse motion, a gear  19  meshes with a gear  23 , which is driven by means of a gear  21  which engages the gear  15  of the differential. 
   In the transmission as illustrated in  FIG. 12 , the secondary cone  6 , in accord with the installation of the cone ring transmission in the motor vehicle, is placed advantageously above the primary cone  4  and is laterally offset therefrom wherein the adjustment ring  8  circumferentially encompasses the secondary cone  6 . For the transmission of the torque to the differential, a sprocket  16  is provided, which is placed on the shaft  7  of the secondary cone  6 , and which connects with a sprocket  17  by means of a chain  13 . The sprocket  17  is rotatably affixed to the sun gear of a planetary gear set  3 . The planetary gear set  3  is provided with a change of direction means  22  for reversing the direction of rotation, wherein, for the reversal of direction, advantageously the internal gear can be coupled to the housing. Further, the planetary gear set  3 , on the power out-take side is connected with a gear  14 , which is engaged with the gear  15  of the differential  9 . As a start-up element  2 , a dry clutch is provided, which is provided with a torsion damper. 
   In the embodiment depicted in  FIG. 13 , it is possible that the secondary cone  6 , in accord with the installation in the motor vehicle, is placed underneath the primary cone  4  and is laterally offset therefrom, whereby the difference to the presentation in  FIG. 12  can be found in that, the adjustment ring  8  circumferentially encompasses the primary cone  4 . 
   In the case of all illustrated examples of embodiments, which possess a planetary gear set, this can be designed as a plus or minus gear set. 
   Obviously, any designed construction, especially any spatial arrangement of the components themselves as well as to one another and to the extent the construction is advantageous, falls under the protection of the present claims, without influence on the function of the transmission, as this is given in the claims, even when these designs are not explicitly presented in the figures nor in the description. Also, the invention is not limited to cones, but additional, rotationally symmetric bodies may be provided. 
   REFERENCE NUMERALS 
   
       
         1  Motor 
         2  (or  2 ′) Start-up element 
         3  Planetary gear set 
         4  Primary cone 
         5  Shaft 
         6  Secondary cone 
         7  Shaft 
         8  Adjustment ring 
         9  Differential 
         10  Auxiliary gear train 
         11  Sprocket for chain 
         12  Sprocket for chain 
         13  Chain 
         14  Gear 
         15  Gear 
         16  Sprocket for chain 
         17  Sprocket for chain 
         18  Gear 
         19  Gear 
         20  Sprocket for chain 
         21  Sprocket for chain 
         22  Arrangement for reversal of rotational direction 
         23  Gear