Patent ID: 12214843

DETAILED DESCRIPTION OF THE INVENTION

FIG.1shows an equivalent circuit diagram of a gear unit1in an upper half-section, with the shift system14in accordance with the invention being shown. A passage shaft11that can be attached in a resting manner at the frame of a two-wheeled vehicle, for example and that can also not rotate to this extent, extends through the gear unit1as a carrying element. The passage shaft11extends along a center axis10that simultaneously forms the axis of rotation of the two planet gears12and13. The planetary gear12forms an inner planetary gear and the planetary gear13forms an outer planetary gear, the two in particular being formed lying in one another.

A drive shaft18that can be driven by a rider or by a motor of the two-wheeled vehicle and that forms a part of the shift system14extends about the passage shaft11. The drive shaft18receives the switch element15and16, with the switch element15cooperating with an annulus gear28of the planetary gear13and the switch element16cooperating with a planet carrier29of the inner planetary gear12. The switch element17cooperates with a sun gear30of the inner planetary gear12and is received at a fixedly stationary part48of the gear unit1and thus provides an operative connection of the inner sun gear30to the fixedly stationary part48and to this extent also to the passage shaft11. The switch element17is thus also part of the switch element14.

The annulus gear28of the outer planetary gear13is divided into two parts with respect to the direction of extent of the center axis10so that a first part gear28ais produced shown on the left and a second part gear28bis produced shown on the right. An axial gap is thereby produced between the part gears28aand28bthrough which the output of the gear unit1is guided, with the output being formed, in a manner not shown in any more detail, by the casing of the gear unit1that is rotationally rigidly coupled to the outer planetary carrier33of the second planetary gear13. The output can, for example, form a casing of the gear unit, not shown in any more detail, that is connected to the planetary carrier33by the gap between the part gears28aand28b.

The outer planet gears34engage in both part gears28a,28bof the annulus gear28so that the part gears28a,28bare rotationally rigidly connected to one another by means of the outer planet gears34.

The first planetary gear12is arranged at the inner side and the second planetary gear13is arranged at the outer side, with both planetary gears12,13being arranged lying in one another and the annulus gear of the first, inwardly disposed planetary gear12being of uniform construction with the sun gear of the second, outwardly disposed planetary gear13and thus forming the annulus sun gear31.

The fixedly stationary part48at which the switch element17is received and that cooperates with the sun gear30can also be formed as part of the passage shaft11, with the fixedly stationary part48advantageously forming a single component or a component group to which the freewheels35and36are also connected, while the freewheel37is configured between the inner sun gear30and the drive shaft18. The freewheel35forms an operative connection of the fixedly stationary part48to the part gear28b, while the freewheel36forms an operative connection of the fixedly stationary part48to the planetary gear29.

FIG.2shows a perspective view of the gear unit1having a drive, shown by a chain24that is guided over a chain pinion43and the chain pinion43is directly operatively connected to the drive shaft18. The passage shaft11that can be fastened to the frame of a two-wheeled vehicle, in particular of a bicycle, by the hub screws41extends through the gear unit1so that the passage shaft11is rotationally rigidly and restingly arranged. In this respect, a fastening arm40that is likewise attached to the frame of the two-wheeled vehicle is located at the passage shaft11in a rigid arrangement to stabilize torques occurring in the gear unit1.

The control of the gear unit1takes place via Bowden cables39that cooperate with a rotational activator31that is likewise rigidly connected to the passage shaft11and that is shown as a functional unit. The output of the gear unit1takes place via the casing32that has means38for receiving wheel spokes.

FIG.3shows an upper half-section of the gear unit1and the passage shaft11that extends in the center axis10and is rigidly arrangeable at the frame of the two-wheeled vehicle is in turn shown as a main component.

The drive shaft18that is designed as hollow and on which the chain pinion43for the rotary drive of the drive shaft18is received extends sectionally about the passage shaft11. The roller element bearings44of the drive shaft18are received in a supporting manner on the passage shaft11. At the inner side, the drive shaft18has, toward the outer circumference of the passage shaft11, a radial gap in which the selector shafts19and20partially extend from a side disposed opposite the arrangement of the chain pinion43. The switch element15and16are received in or at the drive shaft18so that the switch element15and16also rotate to this extent about the selector shafts19and20with the rotation of the drive shaft18about the passage shaft11. The switch element17is received at the fixedly stationary part48. The switch element15is shown in rotated form in the section for the purposes of the view and is actually located at an offset position on the circumference about the center axis10, with all the switch element15,16,17each being present pairwise at oppositely disposed positions.

The first, inner planetary gear12and the outer, secondary planetary gear13with their individual components can be shifted by the switch element15,16, and17. The planetary gears12and13are received within the casing32of the gear unit1, with the casing32serving as the output of the gear unit1while the drive shaft18serves as the drive.

The switch unit14has a rotational activator21that is operatively connected to the selector shafts19and20and that can be activated by an operator to introduce a step-wise, staged rotational movement in discrete angular increments into the selector shaft19,20. The stepwise rotational movement in the selector shafts19,20takes place here relative to the resting passage shaft11and is converted— as described below— into an axial movement along the center axis10.

The selector shaft19,20is in two parts and has a first selector shaft19and a second selector shaft20, with the first and second selector shafts19,20being configured rotationally rigidly but axially movably with respect to one another.

A first component of the planetary gear12,13forms the annulus gear28of the outer, second planetary gear13, with the annulus gear28being divided into a first part gear28aand into a second part gear28b. The first switch element15or a pair of first switch element15here interacts with the annulus gear28, represented by the first part gear28a, to connect it rotationally rigidly to the drive shaft18on engagement of the switch element15. A further component of the planetary gear12,13is represented by the planetary carrier29that is part of the inner, first planetary gear12, with the second switch element16or a pair of second switch element16cooperating with the planetary gear29to rotationally rigidly connect it to the drive shaft18on engagement.

Finally, a further shiftable component of the planetary gears12,13is represented by means of the sun gear30of the first, inner planetary gear12, with the third switch element17cooperating with the sun gear30to rotationally rigidly connect it to a fixedly stationary part48of the gear unit1on engagement. The switch element17is to this extent not received at the drive shaft18, but rather at a fixedly stationary part48that can also be formed in multiple members.

The casing32of the gear unit1is supported at the fixedly stationary part48and furthermore rotatably supported via the drive shaft18by means of roller element bearings44, with the casing32serving as the drive element. For this purpose, the casing32is connected to the outer planetary carrier33of the second, outer planetary gear13. The connection takes place by the axial gap between the part gears28aand28bof the annulus gear28so that one or more webs of the outer planetary carrier33, distributed over the circumference, are connected at least indirectly, in particular via elastic coupling elements, in an arrangement between the circumferential positions of the outer planet gears34.

The first shown freewheel35forms an operative connection between the annulus gear28of the second, outwardly disposed planetary gear13and the fixedly stationary part48. The second shown freewheel36forms an operative connection between the planetary carrier29of the first, inwardly disposed planetary gear12and the fixedly stationary part48, with a third freewheel37being provided that forms an operative connection between the sun gear30and the drive shaft18.

If the gear unit1is switched to the neutral NO, all the switch element15,16, and17are retracted and are not in engagement with the components of the planetary gear12,13in this position.

For a first speed N1, only the switch element15is extended and brought into engagement with the annulus gear28, while the further switch element16,17are not in engagement.

For the second speed N2, only the switch element16is extended and brought into engagement with the planetary carrier29, while the switch element15and17remain retracted.

For the third speed N3, the switch element15and the switch element17are brought into engagement with the annulus gear28or with the sun gear30.

For the fourth speed N4, the switch element15remains retracted, while the switch element16and1are moved into engagement with the planetary carrier29and/or the sun gear30.

For the fifth speed N5, the switch element15and the switch element16are extended, while the switch element17remains retracted.

For the sixth speed N6, finally, all three switch element15,16, and17are extended and moved into engagement with the respective components of the planetary gears12,13.

FIG.4represents a perspective view of the switch unit14with the selector shafts19and20in an arrangement on the passage shaft11, with the rotational activator21furthermore being shown with the Bowden cables39.

The selector shaft19has a guide link22in which a guide element24is guided. The guide element24is rigidly arranged at the passage shaft11and migrates through it transversely to the center axis10. The guide link22has a zig-zag contour so that a direction changing axial movement is introduced along the center axis10into the selector shaft19on a rotation of the selector shaft19by means of the rotational activator21.

The selector shaft20is admittedly received rotationally rigidly, but axially movably with respect to the selector shaft19so that the rotational movement can likewise by introduced into the selector shaft20via the selector shaft19by means of the rotational activator21. A guide link23, in which a guide element25is likewise guided that is rigidly attached to the passage shaft11, is also introduced in the selector shaft20. The guide link23likewise has a zig-zag contour so that the selector shafts19and20can execute a mutually independent axial movement by the two guide links22and23depending on the rotational position of the selector shafts19and20that is set stepwise by the rotational activator21. The selector shaft19can here cooperate with the switch element16and17, while the selector shaft20can cooperate with the switch element15.

FIG.5shows a further perspective view of the main components of the shift system14, with the drive shaft18now being shown that is driven by the chain42in conjunction with the chain pinion43. In this respect, the selector shaft20is arranged inwardly disposed in the drive shaft18and is covered by it so that only the selector shaft19is visible.

The switch element15and16that are each preloaded by tension springs49such that the switch element15,16are extended and can engage into the component of the planetary gears12,13are received in the drive shaft18. The same applies to the switch element17that is likewise shown preloaded by a tension spring49and can cooperate with the shown selector shaft19; however, the switch element17is not received at the drive shaft18, but rather at the fixedly stationary part48, not shown.

There are furthermore shown the guide link22in the selector shaft19with the guide element24at the passage shaft11and the selector shaft19can also be adjusted by the Bowden cables39in the axial position by means of the rotational activator21in the retracted position due to the action of the guide link22.

FIG.6shows the selector shaft20, that can be displaced along the center axis10, in an individual representation in that it is rotatably arranged at the passage shaft11and in that the guide element25extends in the guide link23that Is of zig-zag form. A rotation of the selector shaft20about the center axis10consequently effects a to-and-fro displacement of the selector shaft20on the passage shaft11along the center axis10.

The outer contour of the selector shaft20has a first section A1and a second section A2, with the diameter of the first section A1being smaller than the diameter of the second section A2. The sections A1, A2, shown by way of example, in the outer contour of the shown selector shaft20are likewise present in the further selector shaft19so that the respectively associated sections A1and A2of the switch element15,16, and optionally17, on the selector shafts19,20can cooperate. The following description of the action of the sections A1and A2here applies to all the sections that are associated with the respective switch element and are to this extent generally described in the following for the example of sections A1and A2of the selector shaft20.

If a pickup27, seeFIG.7, of the switch element15,16,17runs off on the first section A1, the switch element15,16,17is extended and engaged in a component of the planetary gears12,13, which is effected by the respective tension springs49. If the selector shaft20and, in the same manner also the selector shaft19, in a manner not shown, is axially displaced in that it is rotated about the passage shaft11by means of the rotational activator21, the resulting axial displacement causes a change of the contact of the pickup27of the switch element15,16,17against the preload force of the tension springs49from the first section A1to the second section A2.

The change can take place due to the circumferential movement of the pickup27along the ramp26so that the pickup27can migrate upward in a certain manner from the smaller diameter to the larger. Since the selector shaft20only defines the contour and the switch element15,16revolve due to the rotation of the drive shaft18about the selector shaft1920, a disengagement of the engagement of the switch element15,16, and thus a release of the force flow from the component of the planetary gear12,13, also takes place without problem under load since the disengagement does not have to be initiated by means of rotational activator21, and thus via the Bowden cables39; the disengagement rather takes place by the drive force to drive the drive shaft18itself, that is therefore via the drive power. The contact of the switch element15,16, and also17, with the respective associated sections A1and A2is held by the tension spring49here that is shown for each of the switch element15,16,17inFIG.5.

The ramp28is formed as a ramp at the radial peripheral side and can release the pickup of the switch element from the contact with the section A1of a smaller diameter and move into contact with the section A2of a larger diameter when the switch element circles the selector shaft20so-to-say with the rotation of the drive shaft. If the drive shaft is stationary and if the pickup or the switch element adopts a fixed peripheral position, a change can nevertheless take place between the contact with the section A1and the contact with the section A2since the selector shaft20has an axial-radial ramp26′ that is formed beside and at the front side of the actual ramp26at the selector shaft20. A gear change can consequently also take place while stationary. The axial-radial ramp26′ is here at least sectionally formed as a cone.

Looking atFIG.7, a simple pivoting of the switch element15,16,17about the pivot axis45is sufficient to move the switch element15,16,17between the selected positions, with the blocking section46on the front side of the switch element15,16,17in particular being convexly contoured such that a simple disengagement from the latched position of the switch element15,16,17from the component of the planetary gear12,13can take place simply and with minimal force.

FIG.8shows a sectioned view of the switch unit14with the drive shaft18with the adjoining rotational activator21in operative connection with the selector shaft19. The switch element16are shown in a two-fold oppositely disposed arrangement, with the switch element16being received in the drive shaft18and running off over the first section A1of the selector shaft19. The switch element15, not shown by the sectional view, is received in the drive shaft18in the same way and the switch element17in conjunction with the tension spring49is not in an arrangement in or at the drive shaft18.

FIG.8afinally shows a sun gear30of the first inner planetary gear12having inwardly disposed pinion pockets47in which the blocking sections46of the switch element17can engage.

The invention is not restricted in its design to the preferred embodiment specified above. A number of variants is rather conceivable that also makes use of the solution shown with generally differently designed embodiments. All the features and/or advantages, including any construction details or spatial arrangements, originating from the claims, the description, or the drawings can be essential to the invention both per se and in the most varied combinations.

REFERENCE NUMERAL LIST

1gear unit10center axis11passage shaft12planetary gear13planetary gear14shift system15switch element16switch element17switch element18drive shaft19selector shaft20selector shaft21rotational activator22guide link23guide link24guide element25guide element26ramp26′ ramp27pickup28annulus gear28afirst part gear28bsecond part gear29planetary carrier30sun gear31annulus sun gear32casing33outer planetary carrier34outer planet gear35first freewheel36second freewheel37third freewheel38means for receiving wheel spokes39Bowden cable40fastening arm41hub screw42chain43chain pinion44roller element bearing45pivot axis46blocking section47pinion pocket48fixedly stationary part49tension springA1first sectionA2second section