Patent Application
20070252427
Referring now to the attached drawings which form a part of this original disclosure:
Selected embodiments of the present invention will now be explained with reference to the drawings. It will be apparent to those skilled in the art from this disclosure that the following descriptions of the embodiments of the present invention are provided for illustration only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.
Referring initially to
As illustrated in
The hub shaft 32 is preferably a hollow shaft member with an internal bore extending completely therethrough. The hub shaft 32 also has an inner circumference surface with a first internal thread 32a located at the first axial end portion and a second internal thread 32b located at the second axial end portion. The hub shaft 32 also has an outer circumference surface with a first external thread 32c located at the first axial end portion and a second external thread 32d located at the second axial end portion. While preferably both axial end portions are internally threaded and externally threaded, it will be apparent to those skilled in the art from this disclosure that only one of the axial end portions can be both internally threaded and externally threaded, if needed and/or desired. The internal threads 32a and 32b are formed at the first and second axial end portions so that the overlap with the external threads 32c and 32d, respectively. Furthermore, the shaft directional length of each of the internal threads 32a and 32b is longer than the shaft directional length of each of the external threads 32c and 32d. In other words, the internal thread 32a of the hub shaft 32 extends farther along the hub shaft 32 toward a middle portion of the hub shaft 32 than the external thread 32c of the hub shaft 32, and the internal thread 32b of the hub shaft 32 extends farther along the hub shaft 32 toward the middle portion of the hub shaft 32 than the external thread 32d of the hub shaft 32. Moreover, the tips of the internal threads 32a and 32b are positioned along the hub shaft 32 in an axial direction toward the middle portion of the hub shaft 32 than first and second bearing support locations of the shaft bearings 34a and 34b, respectively.
In this arrangement, where both inner and outer circumference surfaces are threaded, significant tension tends to be applied to the tip areas where the bolts 37 and the shaft bearings 34a and 34b are screwed onto the first and second axial end portions of the hub shaft 32. In the illustrated configuration, it is preferable that the tip areas are not aligned such that a substantial load is not applied to the hub shaft 32 at the same axial location along the hub shaft 32. Specifically, when the fixing bolts 37 are screwed into the internal threads 32a and 32b of the hub shaft 32 and tightened down, substantial tension is applied to the hub shaft 32 at each bolt tip area 32e of each of the internal threads 32a and 32b of the hub shaft 32 where the free ends of the fixing bolts 37 are located. Also when the shaft bearings 34a and 34b are screwed onto the external threads 32c and 32d of the hub shaft 32 and tightened down, substantial tension is applied to the hub shaft 32 at each innermost bearing side area 32f of each of the internal threads 32a and 32b of the hub shaft 32 where the innermost side portion of the shaft bearings 34a and 34b are located. In addition, during riding the bicycle 10, a significant load is applied to the fixing bolts 37 by the front fork 22. This load on the fixing bolts 37 is transmitted to the hub shaft 32. By attaching the fixing bolts 37 deeper toward the middle portion of the hub shaft 32 than the bearing support locations of the shaft bearings 34a and 34b, a substantial load can be effectively prevented from being applied to the hub shaft 32 at the shaft bearings 34a and 34b.
The shaft bearings 34a and 34b are preferably adjustable cone type ball bearings. The shaft bearing 34a has an outer ring or cup 34c securely pressed in an inner circumference surface of a first end in the hub shell 36, while the bearing 34b has an outer ring or cup 34d securely pressed in an inner circumference surface of a second end in the hub shell 36. The shaft bearing 34a also has an inner ring or cone 34e securely threaded onto the external thread 32c of the hub shaft 32, while the bearing 34b also has inner ring or cone 34f securely threaded onto the external thread 32d of the hub shaft 32. The shaft bearing 34a also has a plurality of roller members or balls disposed between the outer ring or cup 34c and the inner ring or cone 34e, while the shaft bearing 34b has a plurality of roller members or balls disposed between the outer ring or cup 34d and the inner ring or cone 34f. By adjusting the amount that the inner ring or cones 34e and 34f are threaded onto the external threads 32c and 32d, the load or force applied to the roller members or balls can be adjusted to control the play in the shaft bearings 34a and 34b. The shaft bearings 34a and 34b are filled with grease with a pair of grease dispersion preventive members 33a and 33b being attached inwardly of the ball shaft bearings 34a and 34b so as to maintain the grease in the shaft bearings 34a and 34b. In particular, the grease dispersion preventive member 33a is attached to the inner circumference surface of the hub shell 36 so as to come in contact with the outer ring 34c of the ball shaft bearing 34a, where it is situated in opposition to a small gap left on the outer circumference surface of the hub shaft 32. Similarly, the grease dispersion preventive member 33a is attached to the inner circumference surface of the hub shell 36 so as to come in contact with the outer ring 34d of the ball shaft bearing 34b, where it is situated in opposition to a small gap left on the outer circumference surface of the hub shaft 32. Furthermore, both of the grease dispersion preventive members 33a and 33b have cylindrical sections 33c and 33d with outer diameters formed such that they overlap each other on the inner and outer circumference surfaces.
Lock nuts 35a and 35b are attached outside the shaft direction of the ball shaft bearings 34a and 34b. The lock nuts 35a and 35b contact with the inner rings 34e and 34f of the ball shaft bearings 34a and 34b to prevent the inner rings 34e and 34f of the ball shaft bearings 34a and 34b from unthreading. In particular, the lock nuts 35a and 35b are screwed onto the external thread 32c and 32d of the hub shaft 32, respectively, thereby preventing rotation of the inner rings 34e and 34f.
The diameter of the hub shell 36 is small at the center in the axial direction and becomes larger at both ends where a pair of hub flanges 36a and 36b is formed at the outer circumference surface of the large diameter sections. The hub flanges 36a and 36b are coupled to a rim 18a of the front wheel 18 via a plurality of spokes 38, as illustrated in
As seen in
The bolt member 40 is in the form of a hexagonal socket head bolt. The bolt member 40 has a shaft portion with an external thread 40a, a head portion 40b, a washer attachment section 40c and a first annular groove 40d. The external thread 40a is configured to be screwed together with internal thread 32a or 32b. The head section 40b has a large diameter provided at one end of the external thread 40a. The external thread 40a is preferably an M10 screw or the like, and the shaft directional length thereof is approximately 25-30 mm. The outer circumference of the head section 40b is gradually decreased in diameter size toward the end. At the end surface of the head section 40b, a hexagonal tool engagement section 40e is formed to engage an Allen wrench.
The washer member 41 is rotatably attached to the bolt member 40 at the washer attachment section 40c by the retaining member 42. The washer member 41 is able to contact the outside surface of the front claws 22a. The washer attachment section 40c is provided between the head section 40b and the external thread 40a. The washer attachment section 40c is smaller in diameter than the head section 40b, but has a larger outer diameter than the inner diameter of the C retaining ring 42a in a free state. In the washer attachment section 40c, the first annular groove 40d is formed to engage the retaining member 42. The first annular groove 40d is formed slightly deeper than the thickness of the retaining member 42. This enables the retaining member 42 to be decreased in diameter compared to the outer diameter of the washer attachment section 40c when the washer member 41 is attached, thereby allowing smooth attachment of the washer member 41,
The washer member 41 is a ring-shaped member that is thicker than the shaft directional length of the washer attachment section 40c. The washer member 41 is situated between the head section 40b and the front claws 22a when the front bicycle hub 30 is attached to the front fork 22. The outer circumference of the washer member 41 comprises a first tapered section 41a that gradually decreases in diameter towards the head section 40b. Furthermore, the inner circumference comprises a second tapered section 41b that gradually increases in diameter towards the head section 40b. At a position opposite the first annular groove 40d in the inner circumference surface of the washer member 41, a second annular groove 411c is formed to engage the outer circumference of the retaining member 42. The bottom diameter of the second annular groove 41c is the same as, or slightly smaller than, the outer circumference of the retaining member 42 in a free state.
The procedure to couple the washer member 41 to the fixing bolt will now be explained. First, the C-type retaining ring 42a, which is the retaining member 42, is attached to the first annular groove 40d in the washer attachment section 40c of the bolt member 40. After the C-type retaining ring 42a is attached, the washer member 41 is attached to the washer attachment section 40c with a decreasing diameter. At this time, the second tapered section 41b comes in contact with the outer circumference surface of the C-type retaining ring 42a, and the C-type retaining ring 42a can be gradually decreased in diameter. In addition, the washer member 41 is inserted deep inside the washer attachment section 40c, thereby opposing the second annular groove 41c to the first annular groove 40d. The decreased C-type retaining ring 42a in the diameter then becomes larger in diameter due to elasticity and is latched to the second annular groove 41c as well as the both circle grooves 40d and 41c. As a result, the washer member 71 is rotatably coupled to the bolt member 40 to be retained.
As illustrated in
The hub shaft 52 is preferably a hollow shaft member with an internal bore extending completely therethrough. The hub shaft 52 also has an inner circumference surface with a first internal thread 52a located at the first axial end portion and a second internal thread 52b located at the second axial end portion. The hub shaft 52 also has an outer circumference surface with a first external thread 52c located at the first axial end portion and a second external thread 52d located at the second axial end portion. While preferably both axial end portions are internally threaded and externally threaded, it will be apparent to those skilled in the art from this disclosure that only one of the axial end portions can be both internally threaded and externally threaded, if needed and/or desired. The internal threads 52a and 52b are formed at the first and second axial end portions so that the overlap with the external threads 52c and 52d, respectively. Furthermore, the shaft directional length of each of the internal thread 52a and 52b is longer than the shaft directional length of each of the external thread 52c and 52d. In other words, the internal thread 52a of the hub shaft 52 extends farther along the hub shaft 52 toward a middle portion of the hub shaft 52 than the external thread 52c of the hub shaft 52, and the internal thread 52b of the hub shaft 52 extends farther along the hub shaft 52 toward the middle portion of the hub shaft 52 than the external thread 52d of the hub shaft 52. Moreover, the tips of the internal threads 52a and 52b are positioned along the hub shaft 52 in an axial direction toward the middle portion of the hub shaft 52 than first and second bearing support locations of the shaft bearings 54a and 54b, respectively. This is done for the same reason as the front bicycle hub 30, i.e., to avoid load concentration at tip areas 52e and 52f of each of the internal threads 52a and 52b of the hub shaft 52 where the free ends of the fixing bolts 39 are located. In other words, when the shaft bearings 54a and 54b are screwed onto the external threads 52c and 52d of the hub shaft 52 and tightened down, substantial tension is applied to the hub shaft 52 at each innermost bearing side area 52f of each of the internal threads 52a and 52b of the hub shaft 52 where the innermost side portion of the shaft bearings 54a and 54b are located. In addition, during riding the bicycle 10, a significant load is applied to the fixing bolts 39 by the frame. This load on the fixing bolts 39 is transmitted to the hub shaft 52. By attaching the fixing bolts 39 deeper toward the middle portion of the hub shaft 52 than the bearing support locations of the shaft bearings 54a and 54b, a substantial load can be effectively prevented from being applied to the hub shaft 52 at the shaft bearings 54a and 54b.
The shaft bearings 54a and 54b are preferably cone type ball bearings. The shaft bearing 54a has an outer ring or cup 54c securely pressed in an inner circumference surface of a first end (i.e., the hub main section 56c) in the hub shell 56, while the bearing 54b has an outer ring or cup 54d securely screw onto an outer circumference surface of a motive energy carrier 56d that is disposed in a second end in the hub shell 56. The shaft bearing 54a also has an inner ring or cone 54e securely threaded onto the external thread 52c of the hub shaft 52, while the bearing 54b also has inner ring or cone 54f securely threaded onto the external thread 52d of the hub shaft 52. The shaft bearing 54a also has a plurality of roller members or balls disposed between the outer ring or cup 54c and the inner ring or cone 54e, while the shaft bearing 54b has a plurality of roller members or balls disposed between the outer ring or cup 54d and the inner ring or cone 54f. By adjusting the amount that the inner ring or cones 54e and 54f are threaded onto the external threads 52c and 52d, the load or force applied to the roller members or balls can be adjusted to control the play in the shaft bearings 54a and 54b. The shaft bearings 54a and 54b are filled with grease with a pair of grease dispersion preventive members 53a and 53b being attached inwardly of the ball shaft bearings 54a and 54b so as to maintain the grease in the shaft bearings 54a and 54b.
Lock nuts 55a and 55b are attached outside the shaft direction of the ball shaft bearings 54a and 54b. The lock nuts 55a and 55b contact with the inner rings 54e and 54f of the ball shaft bearings 54a and 54b to prevent the inner rings 54e and 54f of the ball shaft bearings 54a and 54b from unthreading. In particular, the lock nuts 55a and 55b are screwed onto the external thread 52c and 52d of the hub shaft 52, respectively, thereby preventing rotation of the inner rings 54e and 54f.
The diameter of the hub shell 56 is small at the center in the axial direction and becomes larger at both ends where a pair of hub flanges 56a and 56b is formed at the outer circumference surface of the large diameter sections. The hub flanges 56a and 56b are coupled to a rim 19a of the front wheel 19 via a plurality of the spokes 38, as illustrated in
The freewheel 58 transmits only unidirectional rotation (traveling direction) to the hub shell 56. The freewheel 58 basically includes a power driver 62 rotatably supported on the outer circumference of the motive energy carrier 56d, and a unidirectional clutch 63 situated between the power driver 62 and the motive energy carrier 56d.
The motive energy carrier 56d is a stepped cylindrical steel member, with an inner circumference surface of one end thereof (leftmost part in
The power driver 62 of the freewheel 58 has a sprocket attachment section 62a for attaching the rear sprocket 60 on the outer circumference. The power driver 62 is rotatably supported on the outer circumference of the motive energy carrier 56d, with the unidirectional clutch 63 being situated between the power driver 62 and the motive energy carrier 56d to transmit only the traveling direction rotation to the motive energy carrier 56d. The power driver 62 is rotatably supported to the motive energy carrier 56d by the freewheel bearings 59a and 59b. The rear sprocket 60 is attached to the sprocket attachment section 62a preferably by a spline connection (i.e., a plurality of axially extending splines) to enable rotation as a unit. The rear sprocket 60 is retained on the sprocket attachment section 62a by an installing bolt 65 that is screwed into an inner circumference surface of the power driver 62. The unidirectional clutch 63 is preferably a claw type that is movably attached to the motive energy carrier 56d to transmit only the traveling direction rotation of the power driver 62 to the motive energy carrier 56d.
The fixing bolts 39 are identical to the fixing bolts 37 for the front bicycle hub 30, except for the axial lengths of the fixing bolts 39 are longer than the axial lengths of the fixing bolts 37. Thus, each of the fixing bolts 39 includes a bolt member 70, a washer member 71 and a retaining member 72, with the only difference compared to the fixing bolts 37 in terms of configuration is that an external thread 70a of the bolt member 70 is longer than the external thread 40a of the bolt member 40. The axial lengths of the external threads 70a are preferably 30-35 mm. This is because the rear bicycle hub 31 is applied to a larger load than the front bicycle hub 30. Thus, when the bolt members 40 and 70 are used in a fixed configuration, the fixing bolts 37 and 39 have optimal force due to an axial thread length of the external threads 40a and 70a in the bolt members 40 and 70.
To secure the front bicycle hub 30 and the rear bicycle hub 31 configured in this way to the rear of the front fork 22 and the frame body 20, respectively, the following procedure is performed to secure them.
In attaching the front bicycle hub 30 to the front fork 22, both ends of the hub shaft 32 are situated in the slits of the front claw 22a with the fixing bolts 37 slightly screwed into the internal threads 32a and 32b in the hub shaft 32 in the slits the front bicycle hub 30 is secured to the front fork 22 using an Allen wrench, which is inserted into the tool engagement sections 40e to rotate the fixing bolts 37 and tightened the fixing bolts 37 at both ends of the hub shaft 32 to the desired torque.
The procedure for attaching the rear bicycle hub 31 is the same. Both ends of the hub shaft 52 are situated in the slits of the rear claws 20a with the fixing bolt 39 slightly screwed into the internal threads 52a and 52b in the hub shaft 52. In this state, the rear bicycle hub 31 is secured to the rear of the frame body 20 when the fixing bolts 39 are tightened at both ends of the hub shaft 52 to the desired torque using the Allen wrench.
The washer members 41 and 71 are attached to the bolt members 40 and 70 so as to make it easier and faster to install the hubs 30 and 31. Furthermore, because the washer members 41 and 71 are coupled to the bolt members 40 and 70 with the retaining members 42 and 72, the washer members 41 and 71 can be coupled to the bolt members 40 and 70 by simply attaching the retaining members 42 and 72 to the bolt members 40 and 70 or the washer members 41 and 71. Thus, coupling the washer members 41 and 71 to the bolt members 40 and 70 can be easily accomplished.
In the previous embodiment, the washer member 41 is coupled to the bolt member 40 by the retaining member 42. However, the retaining member can be attached to the washer member 41 in advance. In this case, the depth of the second annular groove 41c needs to be larger than the diameter direction of the retaining member 42. Furthermore, it is preferable to make the bottom diameter of the first annular groove 40d the same as, or slightly larger than, the inner diameter of the retaining member 42.
The configurations of the fixing bolts (threaded fasteners) are also not restricted to that of the previously discussed embodiment. The fixing bolts can be a bolt with an ordinary washer wherein the washer is not retained on the bolt member. In
Each of the bolt members 140 has an external thread 140a and a head section 140b. The head section 140b is in the form of a hexagonal bolt with a hexagonal tool engagement surface on an outer circumference surface to engage a tool such as a spanner. Moreover, head section 140b has a tool engagement section 140e for the Allen wrench. The external thread 140a of the bolt member 140 is an M9 screw thread. The screw threads of the internal threads 132a and 132b in the hub shaft 132 of the front bicycle hub 30, illustrated in
Each of the bolt members 170 has an external thread 170a and a head section 170b. The head section 170b is in the form of a hexagonal bolt with a hexagonal tool engagement surface on an outer circumference surface to engage a tool such as a spanner. Moreover, head section 170b has a tool engagement section 170e for the Allen wrench. The external thread 170a of the bolt member 170 is an M10 screw thread. Here, the force of the fixing bolts 139 for the rear bicycle hubs 31 and 131 is improved compared to the front bicycle hub 30 by the outer diameter of the external thread 170a. Consequently, the screw threads in the internal thread 52a and 52b of the hub shaft 52 in the rear bicycle hubs 31 and 131, illustrated in
The washer members 141 and 171 have longer axial lengths than that of the previous embodiment as well as smaller outer diameters. The outer circumference surfaces of the washer members 141 and 171 are provided with a large cylindrical portion and a small cylindrical portion. The configuration of the other parts of the fixing bolts 137 and 139, including the retaining members 142 and 172, are the same as that of the previous embodiment, so the explanation thereof will be omitted.
Furthermore, as in the previous embodiment, the axial lengths of each internal threads 132a, 132b, 52a, 52b are longer than that of the corresponding one of the external threads 132c, 132d, 52c, 52d, respectively. Furthermore, the tip of each internal thread 132a, 132b, 52a, 52b (end of the inner side of the axial direction) is positioned deeper toward the inner side of the axial direction than each shaft bearing 34a, 34b, 54a, 54b, respectively.
In addition, as in the previous embodiment, at the tip areas 132e and 52e where the fixing bolts 137 and 139 of the internal threads 132a, 132b, 52a, 52b are screwed together and the attachment sections of the shaft bearings 34a, 34b, 54a, 54b, the hub shaft, and most inner parts 132f and 52f in the axial direction of the hub shafts 132 and 52 are shifted to the axial direction.
In the rear bicycle hub 131, illustrated in
In the previous embodiment, the front bicycle hub or the rear bicycle hub of a BMX bicycle is used as an example to explain the present invention, but the present invention is not restricted to a BMX bicycle and can be applied to all bicycle hub assemblies. In the previous embodiment, the axial lengths of the external and internal threads are different, but it can essentially be the same for the external and internal thread. In this case, needless to say, it is preferable to shift the position of the tip of the fixing bolt and the attachment section of the shaft bearing. Also in the previous embodiment, the hub is illustrated as being secured by a fixing bolt to the frame. The present invention is not restricted to this, so if the hub shaft is hollow, a quick release mechanism can be applied if necessary.
In understanding the scope of the present invention, the term “configured” as used herein to describe a component, section or part of a device includes hardware and/or software that is constructed and/or programmed to carry out the desired function. In understanding the scope of the present invention, the term “comprising” and its derivatives, as used herein, are intended to be open ended terms that specify the presence of the stated features, elements, components, groups, integers, and/or steps, but do not exclude the presence of other unstated features, elements, components, groups, integers and/or steps. The foregoing also applies to words having similar meanings such as the terms, “including”, “having” and their derivatives. Also, the terms “part,” “section,” “portion,” “member” or “element” when used in the singular can have the dual meaning of a single part or a plurality of parts. As used herein to describe the present invention, the following directional terms “forward, rearward, above, downward, vertical, horizontal, below and transverse” as well as any other similar directional terms refer to those directions of a bicycle equipped with the present invention. Accordingly, these terms, as utilized to describe the present invention should be interpreted relative to a bicycle equipped with the present invention as used in the normal riding position. Finally, terms of degree such as “substantially”, “about” and “approximately” as used herein mean a reasonable amount of deviation of the modified term such that the end result is not significantly changed.
While only selected embodiments have been chosen to illustrate the present invention, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made herein without departing from the scope of the invention as defined in the appended claims. Furthermore, the foregoing descriptions of the embodiments according to the present invention are provided for illustration only, and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| JP 2006-122116 | Apr 2006 | JP | national |
