Patent Application
20130299293
This U.S. non-provisional patent application claims priority under 35 U.S.C. §119 of Taiwanese Patent Application No. M440895, filed on May 8, 2012, and of Chinese Patent Application 201220549568.5 filed on Oct. 25, 2012, the contents of all of which are hereby incorporated herein by reference in their entireties.
The present invention relates generally to the field of rotational assemblies and, more particularly, to hubs for rotational assemblies.
The bicycle hub assembly 100 can rotate in response to movement of the chain 18, which can spin the back wheel 14 (and possibly the front wheel 14′) to move the bicycle 10 forward. Additionally, pegs 19 and pegs 19′ are coupled to the back wheel 14 and front wheel 14′, respectively, to enable the rider to perform stunts.
According to
When the second sprocket 132 is rotated counterclockwise by the chain 18, the paw 134 of the driver 130 can slide past the internal teeth 144 of the internal gear ring, so that the body of the hub 120 is not driven (sometimes referred to as “idle running”). In “idle running”, when the paw 134 of the driver 130 slides past the internal teeth 144 on the internal gear ring, a “clicking” noise may occur which is commonly associated with convention hub assemblies.
Referring to
A Freecoaster bicycle hub is also discussed in, for example, Taiwanese Patent Publication Number TW-201113167.
Embodiments according to the present invention can provide rotational hub assemblies that are reconfigurable to have different rotational modes. Pursuant to these embodiments, a rotational assembly hub can include a sprocket that is configured to rotate about an axis, where the sprocket can be located on a first side of a driver. Moveable paws can be located on a second side of the driver that is opposite the first side of the driver. The moveable paws can be configured to move from a recessed position within the driver to a protruding position when the driver rotates in a first direction in a first rotational mode and can be configured to remain protruding from the recessed position when rotated in the first direction in a second rotational mode.
In some embodiments according to the invention, the driver includes troughs, where the hub can further include first removable springs in the troughs that can be configured to provide a first force on the moveable paws toward the recessed position. In some embodiments according to the invention, the troughs each include circular arc shaped sub-troughs located on opposing ends of the troughs. In some embodiments according to the invention, first portions of the first removable springs can be configured for insertion into the sub-troughs. In some embodiments according to the invention, the hub can further include second portions of the first removable springs, wherein the paws each include first and second opposing jaws linked together by a linkage surface that is recessed relative to outer surfaces of the first and second jaws and can be configured to engage with the second portions of the first removable springs.
In some embodiments according to the invention, the driver can include recesses, and the hub can further include second removable springs in the troughs that can be configured to provide a second force on the moveable paws toward the protruding position. In some embodiments according to the invention, the troughs can each include circular arc shaped sub-troughs located on opposing ends of the troughs. In some embodiments according to the invention, first portions of the second removable springs can be configured for insertion into the sub-troughs.
In some embodiments according to the invention, the hub can further include second portions of the second removable springs that can be configured to engage with bottom surfaces of the paws. In some embodiments according to the invention, the hub can further include a clutch that can include a first side thereof facing the first side of the driver to selectively engage with the moveable paws in the first rotational mode. In some embodiments according to the invention, the clutch can include a second side thereof that is opposite the first side of the driver, where the second side can be configured to face the first side of the driver in the second rotational mode, that can be configured to remain spaced apart from the first side of the driver in the second rotational mode.
In some embodiments according to the invention, the hub can further include a spring configured for placement to surround the axis of rotation and to force the clutch to contact the first side of the driver. In some embodiments according to the invention, the hub can be a BMX style bicycle wheel hub. In some embodiments according to the invention, the first rotational mode can be a Freecoaster configuration rotational mode and the second rotational mode can be a Cassette configuration rotational mode. In some embodiments according to the invention, a surface of the paws that faces away from the sprocket is substantially planar and is free on a protrusion. In some embodiments according to the invention,
In some embodiments according to the invention, a BMX bicycle hub can include a rider re-configurable driver including a sprocket configured to rotate about a BMX bicycle axle, the rider re-configurable driver configured to provide a Freecoaster configuration rotational mode in a first configuration and provide a Cassette configuration rotational mode in a second configuration.
In some embodiments according to the invention, a rotational hub assembly can include a driver including a sprocket that can be configured to rotate about an axis of the driver rotation and can include spaced-apart troughs in an outer circumferential surface of the driver and separate springs that can be configured for insertion into each of the spaced-apart troughs in the outer circumferential surface of the driver.
In some embodiments according to the invention, a hub assembly (such as a hub assembly for a BMX style bicycle) can be configured in a “cassette mode” or in a “Freecoaster mode.” In the cassette mode, the hub allow a wheel to be mechanically engaged by paws when the wheel moves in both forward and reverse directions so that, for example, when the wheel rotates backwards, the pedals also rotate backwards. In the Freecoaster mode, however, the hub allows the wheel to be mechanically engaged by paws only when the wheel moves in the forward direction, whereas the wheel is not mechanically engaged by the paws when the wheel moves in the reverse direction. Accordingly, when the wheel rotates backwards in Freecoaster mode, for example, the pedals do not rotate backwards.
In some embodiments according to the invention, a bicycle hub assembly includes an axle, a driver, an internal gear wheel, a hub, clutch and a second elastic spring. The driver is disposed around the axle wherein the driver includes at least one sprocket, a series of troughs, a series of paws and a series of first springs. The sprocket is located on one side of the driver and the trough is located on the opposite side of the driver relative to the sprocket. The trough can have a first sub-trough and a second sub-trough. The paw has a first end and a second end. The first spring has a first end and a second end. The internal gear ring surrounds the paws and a series of teeth (sometimes referred to as gears) on then internal surface of the internal gear ring. A hub is disposed around the axle. The clutch has an axial hole and a cam. The cam has multiple protruding parts. The second spring is disposed around the axle.
In some embodiments according to the invention, a bicycle hub assembly includes an axle, a driver, an internal gear wheel, a hub, a clutch and a second elastic spring. The driver is disposed around the axle, and the driver includes at least one sprocket, a trough, paws and first springs. The sprocket is placed at one side of the driver. The trough is placed at another side of the driver. The trough has a first sub-trough and a second sub-trough and both of the sub-troughs have circular arcs. The trough also includes a bottom surface between the first sub-trough and the second sub-trough. Moreover, the paw has a first end and a second end. The first end of the paw is placed inside the first sub-trough with the first spring, where the first spring has a first end and a second end. The first end of the first spring is placed inside the second sub-trough and the elasticity is provided to the paw by the second end of the first spring.
In some embodiments according to the present invention, internal teeth are included on the interior surface of the internal gear ring. The internal teeth are configured to mechanically engage with the second end of the paw. The hub is disposed around the axle, and the clutch includes an axle hole through which the axle passes. The clutch includes a cam having a plurality of blocks on the cam spaced apart around the circumference thereof to selectively engage with the paws. The second spring is disposed around the axle. The elasticity of the second spring can force the clutch against the paws.
In some embodiments according to the present invention, when the driver spins in a first direction relative to the clutch, the block of the cam will engage with the paws. This action makes the second end of the paw lift out of the trough to mechanically engage with the internal teeth, whereas when the driver spins in the second direction relative to the clutch, the block of the cam disengages from the paws, whereupon the elasticity of the first spring causes the paw to return to the trough. It will be understood that the first direction and the second directions can be opposite to one another.
In some embodiments according to the present invention, the first sub-trough and the second sub-trough are symmetrical to one another.
In some embodiments according to the present invention, the paw includes a first jaw, a second jaw, and a linkage surface linking the first and second jaws together. The linkage surface is configured to be engaged by the second end of the first spring to hold the paw in the trough. The paw will be moved away from the block of the cam of the clutch when the ratchet wheel spins through the second direction. This action makes the elasticity of the first spring force the paw into the trough toward the linkage surface.
In some embodiments according to the present invention, a collar is located around the axle between the clutch and the driver. In some embodiments according to the present invention, the collar includes metal.
In some embodiments according to the present invention, in the Freecoaster configuration mode of rotation, the paws 236 include a first end 236a and a second end 236b, where the both ends 236a and 236b can be recessed inside the first trough 234a so that at least any protrusion of the paws from the trough 234a is small enough to avoid the internal teeth from engaging with the internal gear ring 240 unless engaged by the cam and blocks. The first springs 238 include a first end 238a and a second end 238b, where the first end 238a of the first spring 238 is recessed inside the sub-trough 234b and the second end 238b of first spring 238 provides tension on the paw 236 to keep the paw 236 recessed within the trough 234. The internal gear ring 240 includes internal teeth 242 set on the internal surface of the internal gear ring 240. The internal teeth 242 are suitable for the second end 236b of the paw 236 to mechanically engage when the sprocket 232 rotates in the clockwise direction, for example.
In some embodiments according to the present invention, one end of second spring 260 provides tension on the clutch 250 to press the clutch 250 against the ratchet wheel 230. In some embodiments according to the present invention, this action makes the clutch 250 fit closely together with the ratchet wheel 230. In some embodiments according to the present invention, the hub 200 includes a collar 270. In some embodiments according to the present invention, the collar 270 can be metal and can be placed in the axle hole 252 of the clutch 250 around the axle 210 in different orientations depending on whether the Freecoaster or Cassette configuration rotational mode is used.
In some embodiments according to the present invention, in the Freecoaster configuration mode of rotation, when the second chain wheel 232 is spun by the chain 18 in the clockwise direction, the sprocket 230 will be engaged by the clutch 250 and spin in the first direction A. The block 256 of the cam 254 engages the paw 236 which makes the second end 236b of the paw 236 lift out the trough 234 and engage the internal teeth 242, causing the internal gear ring 240 to spin. When the internal gear ring 240 spins, the hub 220 will follow, thereby moving the bicycle forward.
In some embodiments according to the present invention, in the Freecoaster configuration mode of rotation, when second sprocket 232 is pulled by chain 18 to spin counter-clockwise, however, the driver 236 spins in the second direction B and the block 256 of the cam 254 disengages from the paw 236. In addition, the paw 236 may also disengage from the block 256 of the cam 254 when the wheel spins in a forward direction (assuming that the driver 230 is not spun in the counter-clockwise direction.
In either case, this action allows the paw 236 to be recessed back into the trough 236 (by the tension of first spring 238) to fit closely together with the surface of the bottom 236c. Because the paw 236 is recessed into the trough 234, it can avoid being engaged by the internal teeth 242 of the internal gear ring 240, such as when the bicycle moves backward, which can also avoid creating the “clicking” noise associated with backward movement of some wheels in the prior art.
As described herein, the hub 200 can be configured to be in the Freecoaster mode (described for example above in reference to
Accordingly, the hub can be configured for Freecoaster mode or Cassette mode by swapping the particular springs used to engage with the paws. For example, the first springs can be used to hold the paws in the troughs (until engaged by the blocks) in Freecoaster mode, whereas the second springs can be used to force the paws to protrude from the troughs without engagement of the blocks.
Relative terms such as “below” or “above” or “clockwise” or “counterclockwise” may be used herein to describe a relationship of one element to another element as illustrated in the figures. It will be understood that these terms are intended to encompass different orientations of the assemblies in addition to the orientation depicted in the figures.
Although the present invention has been described in connection with the embodiment of the present invention illustrated in the accompanying drawings, it is not limited thereto. It will be apparent to those skilled in the art that various substitution, modifications and changes may be thereto without departing from the scope and spirit of the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| M440895 | May 2012 | TW | national |
| 201220549568.5 | Oct 2012 | CN | national |
