INTERNAL CONNECTION OF A BICYCLE REAR HUB

Abstract

The invention refers to the internal connection of a rear bicycle wheel hub (1) comprising a cylindrical body (2) that surrounds an axle (3), where a proximal end (2b) of the body (2) is attached to a freehub body (4) that surrounds a freewheel system (6). A connecting mechanism (5) between the body (2) and the freewheel system (6) of the freehub body (4) is characterized in that it comprises a connecting crown (7) coupled to an inner surface (2c) of the body (2) that connects with a ring (6a) in the freewheel system (6) and an elastic ring (8) seated in a circular recess (9) on a lateral surface (7c) of the connecting crown (7) so that it can expand towards the inner surface (2c) of the body (2) and fix the connecting crown (7) inside the body (2).

Claims

1. Rear bicycle wheel hub comprising a cylindrical body that surrounds an axle, wherein at a distal end comprises a distal stop and at a proximal end a freehub body is attached by means of a connecting mechanism, where the freehub body comprises a cylindrical body that surrounds a freewheel system and a proximal stop at a proximal end of the freehub body that closes and fixes the hub, where the body of the rear hub is characterized in that: the connecting mechanism between the body and the freewheel system of the freehub body comprises a connecting crown and an elastic ring, where the connecting crown comprises a lateral surface with a circular groove where the elastic ring is fitted so that it can expand towards the internal surface of the body and fix the connecting crown inside the body.

2. Rear bicycle wheel hub, according to claim 1, where the connecting crown comprises a regular or irregular external surface with crenellations and/or splines, complementary to the inner surface of the body and an inner radial surface complementary to the outer surface of at least one toothed ring of the freewheel system.

3. Rear bicycle wheel hub, according to claim 1, wherein the elastic ring comprises a circular flat body with two free ends where the free end has a tab.

4. Rear bicycle wheel hub, according to claim 1, wherein the body comprises a groove or channel at the proximal end of the inner surface.

5. Rear bicycle wheel hub, according to claim 1, wherein the free wheel system comprises at least two toothed rings laterally facing each other with external teeth or splines complementary to the inner surfaces of the connecting crown and the freehub body.

6. Rear bicycle wheel hub, according to claim 1, wherein the freewheel system comprises at least one pawl system on the outer surface of the distal end of the freehub body.

7. Rear bicycle wheel hub, according to claim 6, wherein the connecting crown comprises a regular or irregular outer surface with crenellations and/or splines, complementary to the inner surface of the body and an inner radial surface complementary to the outer surface of at least one pawl system in the freehub body.

8. Rear bicycle wheel hub according to claim 1, wherein the crenellated and/or splined connecting crown comprises a toothed lateral surface complementary to the outer surface of a ring of the freewheel system.

9. Rear bicycle wheel hub, according to claim 1, wherein the body comprises at least one wheel bearing inside.

10. Rear bicycle wheel hub, according to claim 1, wherein the freehub body comprises at least one wheel bearing inside.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0014] The details of the invention can be seen in the accompanying figures, which are not intended to limit the scope of the invention:

[0015] FIG. 1 shows a perspective view of a bicycle rear hub that is part of the state of the art.

[0016] FIG. 1A shows a perspective view of the connecting mechanism between the hub body and the freehub body in an embodiment that is part of the state of the art.

[0017] FIG. 2 shows an exploded perspective view of the rear hub of the invention.

[0018] FIG. 3 shows a locally enlarged exploded view of the connecting mechanism between the hub and the freehub.

[0019] FIG. 4 shows a locally enlarged view of the connection mechanism of the invention between the hub body and the freehub.

DETAILED DESCRIPTION OF THE INVENTION

[0020] The invention refers to a rear hub system (1) of a bicycle. Specifically, it relates to the connecting mechanism (5) of the body (2) and the freehub body (4) of a rear hub (1) of a bicycle as seen in FIGS. 2, 3 and 4.

[0021] FIGS. 1 and 1A show an exploded view and a locally enlarged view of a rear hub system (1) known as a ratchet system, which comprises, from left to right, a distal stop (1a), a body (2), an axle (3) with wheel bearings (11, 12), a freehub body (4) and a proximal stop (1b). The rear hub (1) between the body (2) and the freehub body (4) comprises a connecting part (5a) and a freewheel system (6). In this ratchet type of rear hub, the freewheel system (6) works through the interaction between the connecting part (5a), which is normally externally threaded and has internal splines, and the two rings (6a, 6b) facing each other, with external splines and laterally toothed with equal and complementary lateral teeth, pushed by two springs (6c) external to them, which make up the freewheel system (6) as shown in FIG. 1A. The connecting part (5a) which is normally threaded externally for fastening to the body (2) and internally splined for holding the freewheel system (6), is the most important part in the connection and fastening of the freehub body (4) to the body (2). As a result, and based on the workload it undergoes after continued use, it generates problems when it has to be replaced, as mentioned above.

[0022] Therefore, the invention refers to a bicycle wheel rear hub (1) that also comprises a cylindrical body (2) that surrounds an axle (3) and where at a distal end (2a) it comprises a distal stop (1a) and at a proximal end (2b) a freehub body (4) is attached by means of a connecting mechanism (5), where the freehub body (4) comprises a cylindrical body, a freewheel system (6) within it and a proximal stop (1b) at a proximal end (4b) of the freehub body (4). However, as shown in FIG. 2, the body (2) of the rear hub (1) of the invention is characterized in that the connecting mechanism (5) between the body (2) and the freewheel system (6) comprises a connecting crown (7) and an elastic ring (8), which are the key innovative parts of the invention.

[0023] On the one hand and preferably, the connecting crown (7) comprises an external crenellated and/or splined surface (7a), an inner radially toothed surface (7b) and a lateral surface (7c). The external crenellated and/or splined surface (7a) and the internal toothed surface (7b) act as a support and link between the body (2) of the hub (1) and the rings (6a, 6b) of the freehub body (4) responsible for the effect of the freewheel system (6), ensuring the solidity and firmness necessary for holding the freehub body (4), by means of a sliding adjustment. In other words, the outer surface (7a) and inner surface (7b) require shapes which may be regular or irregular, but which must be complementary to the surfaces with which they are going to be matched. The lateral surface (7c) comprises a circular recess (9) where the elastic ring (8) is attached or seated.

[0024] Also, preferably, the crenellated and/or splined outer surface (7a) of the connecting crown (7) is complementary to the inner surface (2c) of the body (2), while the inner radial surface (7b) of the connecting crown (7) is toothed and complementary to the outer surface of the ring (6a) of the freewheel system (6) as seen in FIG. 3.

[0025] On the other hand, as shown in FIGS. 3 and 4, the elastic ring (8) of the rear hub (1) of the invention comprises a circular flat body with two free ends (8a, 8b) so as to be able to expand towards the inner surface (2c) of the body (2) and fit into a groove or channel (2d) in the inner radial surface (2c) of the proximal end (2b) of the body (2) of the hub (1) and block the sliding movement of the connecting crown (7), guaranteeing the absolute immobility of the connecting crown (7) inside the body (2). In addition, the free end (8b) comprises a tab (10) that facilitates the extraction of the elastic ring (8) from the body (2) when it is seated and expanded in the groove (2d) of the inner surface (2c) of the body (2).

[0026] Optionally, the freewheel system (6) comprises at least two moving rings (6a, 6b) that are laterally toothed and have external splines, facing each other, and at least two springs (6c) on the other side from the toothed surface of the rings (6a, 6b), which together with the rotation of the pedals determine the operation of the freewheel system (6). In other words, the first ring (6a) fits externally with the complementary splines of the inner radial surface (7b) of the connecting crown (7) and the second ring (6b) fits laterally with the complementary teeth of the first ring (6a) and externally with the inner surface of the freehub body (4). The teeth of the rings (6a, 6b) form a wedge shape, one side being inclined and the other straight. In this way, when pedalling on the bicycle, the sprockets make the freehub body (4) turn and thus turn the rings (6a, 6b) of the freewheel system (6), which are facing each other and in contact due to the fact that the springs (6c) are partially extended, exerting pressure on one ring (6a) against the other (6b). Therefore, when the pedals turn in the direction of travel, the teeth mesh, turning the body (2) and with it the bicycle wheel. However, when pedalling is stopped or reversed, the springs (6c) are slightly compressed and the freewheel system (6) disengages releasing and allowing both rings (6a, 6b) to slide, since the teeth rotate in the opposite direction allowing the wheel to turn when the pedals are immobile or rotate in the opposite direction to the direction of travel.

[0027] Another possible embodiment of the invention is when the freehub body (4) comprises at least one pawl system on an external surface of the distal end (4a) and the connecting crown (7) comprises an inner radially toothed surface (7b) complementary to the pawls of the freehub body (4). Alternatively, in another embodiment, the connecting crown (7) comprises a lateral radially toothed surface (7c) complementary to the outer surface of a ring (6b) of the free wheel system (6), where in this case, the use of one of the toothed rings (6a) is eliminated, being the connecting crown (7) the connecting mechanism (5) and ring (6a) at the same time.

[0028] Additionally, as shown in the Figures, the rear hub (1) of the invention comprises wheel bearings (11, 12) on the axle (3), where the wheel bearings (11) are those located inside the body (2) and the wheel bearings (12) are those located inside the freehub body (4), allowing and helping them to rotate when necessary.

[0029] For all of the above and thanks to the connecting mechanism (5) of the invention, the problem of over-tightening of the threaded connecting part (5a) is solved, facilitating the disassembly and replacement of the necessary parts without the need for tools or special knowledge, thus simplifying and reducing the cost of maintenance work. In addition, it is possible to prolong the life of the hub (1) and therefore of the bicycle wheel.