BICYCLE WITH CANTILEVERED SINGLE SIDE MOUNTED WHEELS

Abstract

An injection moulded cantilevered single side mountable wheel for a bicycle, a rim; a central hub; and a plurality of hollow spokes connecting the rim to the central hub.

Claims

1. An injection moulded cantilevered single side mountable wheel for a bicycle, comprising: a rim; a central hub, and a plurality of hollow spokes connecting the rim to the central hub.

2. The wheel of claim 0, wherein the central hub is offset from a plane defined by a centreline of the rim.

3. The wheel of claim 1, wherein the rim comprises a hollow cross section.

4. (canceled)

5. The wheel of claim 1, wherein an inner wheel hub surface of the wheel comprises a plurality of inner drain holes.

6. The wheel of claim 0, wherein each inner drain hole of the plurality of inner drain holes is aligned with an innermost end of a respective one of the plurality of hollow spokes.

7. The wheel of claim 1, wherein an outer surface of the rim comprises a plurality of outer drain holes.

8. The wheel of claim 7, wherein each outer drain hole of the plurality of outer drain holes is aligned with an outermost end of a respective one of the plurality of hollow spokes.

9. The wheel of claim 7, wherein each outer drain hole of the plurality of outer drain holes comprises a surrounding reinforcement region.

10. The wheel of claim 9, wherein a linear size of the reinforcement region is between 2.0 and 4.0 times larger than a linear size of the respective outer drain hole, preferably between 2.0 and 3.0 times larger, most preferably 2.5 times larger.

11. The wheel of claim 7, wherein the outer drain holes are substantially elliptic; wherein a width of each outer drain hole is between 6 mm and 10 mm, preferably between 7 mm and 9 mm, and most preferably 8 mm; and wherein a length of each outer drain hole is between 16 mm and 24 mm, preferably between 18 mm and 22 mm, and most preferably 20 mm.

12. (canceled)

13. The wheel of claim 1, further comprising a tyre valve stem hole in the outer surface of the rim configured to receive a tyre valve stem, wherein the tyre valve stem hole comprises a surrounding reinforcement region.

14. The wheel of claim 9, wherein each reinforcement region is between 1.5 and 3.0 times thicker than a nominal thickness of the outer surface, preferably between 2.0 and 3.0 times thicker, most preferably 2.5 times thicker and wherein the nominal thickness of the outer surface is between 1.5 mm and 3.5 mm, preferably between 1.9 mm and 3.1 mm, more preferably between 1.9 mm and 2.1 mm, and most preferably 2.0 mm.

15. (canceled)

16. The wheel of claim 1, wherein the wheel comprises a hub interface surface arranged to abut against a bicycle when the wheel is mounted to the bicycle, and wherein the abutment surface is offset from the plane defined by the centreline of the rim.

17. The wheel of claim 16, wherein an axis of each hollow spoke extending along the length of each spoke is curved.

18. The wheel of claim 1, wherein a cross sectional area of each hollow spoke decreases smoothly in a direction radially outwardly from the centre of the wheel.

19. The wheel of claim 1, further comprising a central spar running symmetrically within each hollow spoke and perpendicular in plane to the plane defined by the centreline of the rim.

20. (canceled)

21. The wheel of claim 1, wherein a hub of the wheel comprises a plurality of through holes parallel to a central rotation axis of the wheel arranged to receive a respective plurality of bolts.

22. The wheel of claim 1, wherein the wheel is a lost core injection moulded single side mountable wheel or a soluble core injection moulded single side mounted wheel.

23. The wheel of claim 1, wherein the wheel is made of glass filled nylon.

24. (canceled)

25. A bicycle comprising the wheel of claim 1.

26. (canceled)

27. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Examples of the present invention will now be described in detail with reference to the accompanying drawings, in which:

[0063] FIG. 1 shows a side view of a bicycle with cantilevered single side mounted wheels;

[0064] FIG. 2 is a perspective view of the rear cantilevered single side mounted wheel fitted to the bicycle;

[0065] FIG. 3 shows a perspective view of the cantilevered single side mounted wheel showing a cutaway section through a spoke and the rim of the cantilevered single side mounted wheel from FIG. 2;

[0066] FIG. 4 is a vertical cross section view showing the cantilevered single side mounted wheel mounted to a front wheel hub and front fork shaft assembly of the bicycle; and

[0067] FIG. 5 shows an example of a spoke having central spar.

DETAILED DESCRIPTION OF THE INVENTION

[0068] FIG. 1 shows a bicycle with a cantilevered single side mounted wheel.

[0069] As shown in FIG. 2, the bicycle has a rear rotatable wheel hub 23 with a rigidly mounted disk brake rotor 7 interfacing with a brake calliper 3 which is rigidly mounted to the bicycle 1. A tyre 4 is fitted to the cantilevered single side mounted wheel 2 which is mounted to the rear rotatable wheel hub 23 with a plurality of wheel hub collar mounting bolts 6 compressing a wheel hub collar 5 against the cantilevered single side mounted wheel 2 such that it is rigidly attached to the rear rotatable wheel hub 23.

[0070] A perspective view of the cantilevered single side mounted wheel 2 is shown in FIG. 3 showing a cutaway section through a curved wheel spoke 11, a centre wheel hub 21, and a wheel rim inner profile 22 and a wheel rim tube contact surface 8. The cantilevered single side mounted wheel 2 is of uniform construction and homogenous material throughout.

[0071] The nature of the material of the cantilevered single side mounted wheel 2 is ideally of the fibre reinforced plastic variety that can be injected in a heated and liquid form into a mould followed by cooling and solidification. The process of manufacture of the cantilevered single side mounted wheel 2 is of the so-called “lost core” or “soluble core” injection moulding process whereby a solid, usually metal, core is used to form the internal hollow structure during the injection moulding stage and subsequently removed by dissolving the core and flushing or draining it out of the part.

[0072] The cantilevered single side mounted wheel 2 is formed with a generally circular and conical centre wheel hub 21 coaxial with the centre of rotation of the cantilevered single side mounted wheel 2 and having a substantially orthogonal and planar wheel hub interface surface 19 which is ideally parallel with the vertical plane of the cantilevered single side mounted wheel 2. The centre wheel hub 21 and wheel hub interface surface 19 could alternatively be combined to form a conical tapered shape.

[0073] Through the wheel hub interface surface 19 is a plurality of wheel hub mounting bolt holes 9 for the purpose of attaching the cantilevered single side mounted wheel 2 to the bicycle 1. Within the centre wheel hub 21 a plurality of inner spoke drain holes 10 exist roughly aligned with each curved wheel spoke 11.

[0074] The purpose of the inner spoke drain holes 10 is to enable the inner core of the “lost core” manufacturing process to be removed following the solidification of the material of the cantilevered single side mounted wheel 2. The shape of each inner spoke drain hole 10 is roughly round (e.g. circular) or elliptical and of smooth and uniform geometry with minimal sharp edges or corners.

[0075] Each curved wheel spoke 11 has a generally hollow “box section” design and is of uniform thickness. Ideally there are five curved wheel spokes 11 in order to reduce material stresses imparted from the curved wheel spokes 11 into the wheel rim inner profile 22, although wheels with other numbers of spokes are also envisaged, such as three or more spokes.

[0076] Connected uniformly and with continuous and smooth transition of shape to the curved wheel spokes 11 are the wheel rim inner profile 22 and the wheel rim tube contact surface 8 which form a generally hollow “box section” design able to receive a bicycle tyre and tube. The wheel rim inner profile 22 and wheel rim tube contact surface 8 have a tyre valve stem hole 13 which is able to receive a bicycle tube valve stem for the purpose of inflating the tube and tyre with air.

[0077] Roughly aligned with each curved wheel spoke 11, the wheel rim tube contact surface 8 has a plurality of outer spoke drain holes 12. The purpose of the outer spoke drain holes 12 is similar to that of the inner spoke drain holes 10, which is to enable the inner core of the “lost core” manufacturing process to be removed following the solidification of the material of the cantilevered single side mounted wheel 2. The shape of the inner spoke drain holes 10 is roughly round or elliptical and of smooth and uniform geometry with minimal sharp edges or corners.

[0078] Although the drain holes 10, 12 are illustrated aligned with the spokes 11, additional drain holes could also be positioned in other locations, for example at the regions between spokes.

[0079] FIG. 4 is a vertical cross section view showing a cantilevered single side mounted wheel 2 fitted to a front rotatable wheel hub 14 at the centre wheel hub 21 and a front wheel hub bearing 15 with a plurality of wheel hub collar mounting bolts 6 and a wheel hub collar 5. The purpose of the wheel hub collar 5 is to spread the compression loading from each wheel hub collar mounting bolt 6 evenly across the cantilevered single side mounted wheel 2 in order to reduce material stresses.

[0080] The front rotatable wheel hub 14 is rotatably mounted to a front fork shaft assembly 18 which is fitted with a brake calliper 3 that interfaces with a disk brake rotor 7 which is rigidly mounted to the front rotatable wheel hub 14.

[0081] Each curved wheel spoke 11 is generally curved and offset from the centreline plane of the 2 in order to allow space for the brake calliper 3. Similarly, the wheel hub interface surface 19 is offset substantially to one side of the centreline plane of the cantilevered single side mounted wheel 2 in order to allow space for the brake calliper 3.

[0082] Each outer spoke drain hole 12 is surrounded by an outer spoke drain hole reinforcement region 16 which is generally two times thicker than the nominal thickness of the wheel rim tube contact surface 8. The purpose of the outer spoke drain hole reinforcement region 16 is to reduce material stresses around the front fork shaft assembly 18.

[0083] The size and shape of the outer spoke drain hole reinforcement region 16 is generally greater than two times that of the outer spoke drain hole 12 and is blended smoothly into the wheel rim tube contact surface 8.

[0084] Similarly, the tyre valve stem hole 13 is surrounded by a tyre valve stem hole reinforcement region 20 which is generally greater than two times thicker than the nominal thickness of the wheel rim tube contact surface 8 and the wheel rim inner profile 22. The purpose of the tyre valve stem hole reinforcement region 20 is to reduce material stresses around the tyre valve stem hole 13.

[0085] The size and shape of the tyre valve stem hole reinforcement region 20 is generally greater than two times that of the tyre valve stem hole 13 and is blended smoothly into the wheel rim tube contact surface 8.

[0086] The cantilevered single side mounted wheel 2 is formed with a rim tyre profile 17 which is able to receive a standard bicycle tyre and tube.

[0087] FIG. 5 shows a cross section of a spoke 11 having an optional central spar web structure 24. The central spar 24 may run for all or part of the length of the spoke 11 and runs symmetrically within the spoke 11 in a plane perpendicular to the plane defined by the centreline of the outer rim of the wheel 2. The central spar 24 stabilises the spoke 11 during cooling in the moulding process as well as stabilising the outer shape of the spoke 11 in order to raise the lateral stiffness of the wheel 2.