MECHANISM FOR TRANSMITTING A ROTARY MOVEMENT WITH VARIABLE TRANSMISSION RATIO

• US 20140248982A1
• Filed: 07/18/2012
• Published: 09/04/2014
• Est. Priority Date: 07/27/2011
• Status: Active Grant

• Current Assignee: Praxis Works LLC
• Original Assignee: VYRO components GmbH
• Inventors: Schuster, Gregor
• Granted Patent: US 9,499,233 B2
• Time in Patent Office: Days
• US Class Current: 474/69
• CPC Class Codes: B62M 9/06 using a single chain, belt, or the like
• CPC Class Codes: B62M 9/08 involving eccentrically- mounted or elliptically-shaped driving or driven wheel; with expansible driving or driven wheel
• CPC Class Codes: B62M 9/10 involving different-sized wheels, e.g. rear sprocket chain wheels selectively engaged by the chain, belt, or the like bicycle hubs rotatably arranged on axle B60B27/023
• CPC Class Codes: B62M 9/105 involving front sprocket chain-wheels engaged by the chain, belt or the like
• CPC Class Codes: B62M 9/14 the wheels being laterally shiftable

Abstract

A control mechanism (800) for setting a transmission ratio between a traction means (812), in particular chain, and a wheel set that is rotatable about a wheel axle and includes two or more wheel blades (810, 820, 830), in particular sprocket blades, adjusts the wheel rim sectors relative to a fixed plane of the traction means in a direction transverse to the plane of alignment. At least one of the wheel blades is composed of a plurality of independently adjustable wheel rim sectors (802, 803). By means of a control component (807) mounted decoupled from a rotary movement of the wheel set, a plurality of co-rotating thrust elements (804, 805) are each displaced via rotation-free couplings between a first and a second position at least in the axial direction, wherein each of the wheel rim sectors is connected in a rotationally fixed manner to a respectively associated thrust element. The first position of a thrust element corresponds to the position of the associated wheel rim sector outside the plane of alignment, whereas a thrust element located in the second position exerts on the respective wheel rim sector, at least as long the latter is outside the plane of the traction means, a force for displacing the respective wheel rim sector into the plane of alignment, thus shifting the same into the plane.

Claims

1. A control mechanism (200, 300, 500, 600, 660, 700, 800, 900) for setting a transmission ratio between a traction means (206, 309, 512, 606, 706, 812, 912) and a wheel set that is rotatable about a wheel axle and includes two or more wheel blades (202, 220, 230;

310, 320, 330;

510, 520;

610, 620, 630;

710, 711, 712;

810, 820, 830) which can facultatively be wrapped around by the traction means, wherein at least one of the wheel blades is composed of a plurality of independently adjustable wheel rim sectors (203, 204;

301, 302;

501;

621, 631;

661;

711, 712;

802, 803;

902), wherein the control mechanism causes the adjustment of the wheel rim sectors relative to a fixed plane (“

plane of alignment”

) in which the traction means wraps around the wheel set, in a direction substantially transverse to the plane of alignment,

characterized by

at least one control component (212;

304;

504a, 505;

730;

807;

908) mounted decoupled from a rotary movement of the wheel set,

a plurality of co-rotating thrust elements (216;

306;

504b;

701;

804, 805;

906), wherein a thrust element is each associated to the wheel rim sectors and each of the wheel rim sectors is connected to the respectively associated thrust element so as to be rotationally fixed relative to the rotation about the wheel axle,

wherein the thrust elements are each displaceable via rotation-free couplings between a first and a second position by the at least one control component at least in the axial direction, wherein the first position of a thrust element corresponds to the position of an associated wheel rim sector outside the plane of alignment, whereas a thrust element being in the second position exerts on the respective wheel rim sector, at least as long the latter is outside the plane of alignment, a force for displacing the respective wheel rim sector into the plane of alignment.

2. A control mechanism according to claim 1, characterized in that the thrust elements are each connected to the associated wheel rim sectors and/or the control component by a resilient connection (303, 503, 813) providing a play in a direction transverse to the plane of alignment.

3. A control mechanism according to claim 1 or 2, characterized by a guide disc (205, 311, 511, 811) extending in parallel with the plane of alignment and mounted to co-rotate with the wheel set.

4. A control mechanism according to any one of claims 1 to 3, characterized by additional spring elements (217, 307, 601, 508), which are preferably configured as leaf springs, for returning the wheel rim sectors into a resting position outside the plane of alignment when the associated thrust element assumes its first position.

5. A control mechanism according to any one of the preceding claims, characterized by guide elements associated to the wheel rim sectors (203, 204, 301, 302, 802, 803) and configured as guide pins (209, 804, 805) and/or tilting brackets (303), through which substantially axial movements of the wheel rim sectors are defined, based on the action of force by the respectively associated thrust elements.

6. A control mechanism according to any one of the preceding claims, characterized in that the wheel rim sectors (501, 640) are tiltable relative to the plane of alignment and fastened by means of a spring (508, 601), which exerts a force onto the wheel rim sectors for movement out of the plane of alignment.

7. A control mechanism according to any one of the preceding claims, characterized in that the wheel rim sectors (501) comprise firmly connected, at least in the axial direction, guide projections (507) engaging an associated guide web (506) when the respective wheel rim sector is in the plane of alignment, said guide web (506) being mounted decoupled from a rotary movement of the wheel set.

8. A control mechanism according to any one of the preceding claims, characterized in that the wheel blades have different circumferential radii, one wheel blade (202, 310, 510, 610, 710, 810) having the smallest circumferential radius and being undivided.

9. A control mechanism according to claim 8, characterized in that the undivided wheel blade is mounted on the wheel set so as to be immovable in the axial direction.

10. A control mechanism according to claim 8, characterized in that the undivided wheel blade comprises at least one opening, through which extend at least one thrust element (504b, 701) and/or at least one connection element (503, 702) associated to a thrust element and serving to connect the thrust element to the respective wheel rim sector (501, 721).

11. A control mechanism according to any one of the preceding claims, characterized in that sprocket sectors each located in the same angular region are combined to a sector block.

12. A control mechanism according to claim 11, characterized by a casing (901) arranged about the wheel axle and surrounding a cavity (910) at least partially located laterally of the plane of alignment, into which parts of the sector blocks (902) located outside the plane of alignment can be moved in the axial direction.

13. A control mechanism according to claim 12 provided in a wheel that is rotatable about the wheel axle and includes spokes and/or a wheel disc, characterized in that the casing (901) is arranged within a hub casing (911), which serves as hub-side connection site for the spokes or wheel disc, respectively, and is optionally rotatable relative to the hub casing (911) by the aid of a freewheel mechanism (913).

14. A control mechanism according to claim 12 or 13 provided in a wheel that is rotatable about the wheel axle and includes spokes and/or a wheel disc, characterized in that the cavity (910) extends into an axial region corresponding to the axial position of the spokes or wheel disc, respectively.

15. A control mechanism according to any one of the preceding claims, characterized in that the control component(s) (908) mounted decoupled from the rotary movement of the wheel set is/are arranged in a central cavity (905) extending along the wheel axle and is/are linearly adjustable along the wheel axle, said rotationally free coupling being realized by thrust elements in the form of projections (906) projecting into the central cavity (905) and engaging the control component(s) (908).

16. A control mechanism according to any one of the preceding claims, characterized in that the wheel rim sectors (661) are tiltable relative to the plane of alignment by the aid of retaining elements (663) mounted close to the axle in such a manner as to be pivotable about an axis of rotation (665) extending transversely to the wheel axle, and extend outwardly therefrom, wherein the wheel rim sectors (661) are attached to outer regions of the retaining elements (663), optionally via carrier components (662).

17. A control mechanism according to any one of the preceding claims, characterized in that the wheel rim sectors (671) are equipped with spring elements (674, 684), each spring element causing the switching of the respectively associated wheel rim sector between a position within the plane of alignment and a resting position outside the plane of alignment.

18. A control mechanism according to any one of the preceding claims, characterized in that the wheel blades are sprockets and the wheel rim sectors are sprocket sectors, wherein the traction means is a chain advantageously form-lockingly cooperating with teeth of the sprockets or sprocket sectors.

19. A gearshift comprising a control mechanism according to any one of the preceding claims mounted on a gearwheel.

20. A gearshift according to claim 19 used as a transmission gear and capable of being arranged between a driving gear group and a driven gear group of a vehicle, in particular bicycle.