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Title:
A TYRE, A WHEEL STRUCTURE FOR USE WITH THE TYRE AND A METHOD OF MANUFACTURE OF A TYRE
Document Type and Number:
WIPO Patent Application WO/2016/038398
Kind Code:
A1
Abstract:
The present invention relates to a tyre (20) which has an annular band (4) which carries an annular flexible web (8). The web (8) is encasted in a flexible tyre material (20b) which supports the flexible web (8). A tread (20b) may be provided on the tyre (20) and the band (4) forms the rim (4) of a bicycle.

Inventors:
ANDREWS MICHAEL (GB)
ANDREWS PAUL (GB)
Application Number:
PCT/GB2015/052658
Publication Date:
March 17, 2016
Filing Date:
September 14, 2015
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
CAPAK LTD (GB)
International Classes:
B60C7/10; B29D30/04; B60C7/18
Domestic Patent References:
WO2014036415A12014-03-06
Foreign References:
US20110079335A12011-04-07
US20090173421A12009-07-09
US20110248554A12011-10-13
DE269533C1914-01-22
Other References:
None
Attorney, Agent or Firm:
PHILLIPS, Patricia et al. (5th Floor Blackfriars House,The Parsonage, Manchester Lancashire M3 2JA, GB)
Download PDF:
Claims:
CLAIMS

1 . A tyre having a rim with a tyre material formed on the rim, wherein the rim comprises two concentric, annular bands which are interconnected by a resilient web, and the tyre material comprises at least one resilient tyre material within the web.

2. A tyre according to claim 1 , wherein the web is substantially embedded in the resilient tyre material.

3. A tyre according to claim 1 or 2, wherein the resilient tyre material forms a side wall to the tyre.

4. A tyre according to claim 1 , 2 or 3, wherein the tyre material comprises at least one harder tyre material which forms a tread region to the tyre on an outwardly facing circumferential edge to the tyre.

5. A tyre according to any one of the preceding claims, wherein the

concentric bands include an outer band and an inner band, wherein at least the outer band is resilient.

6. A tyre according to any one of claims 1 to 4, wherein the concentric bands include an inner band which provides at least one of a braking surface and a connection means for spokes of a wheel.

7. A tyre according to any one of the preceding claims wherein the web includes a series of resilient fingers extending between the bands, void areas between the fingers being substantially filled by the resilient tyre material which may comprise a low-density cellular material.

8. A tyre according to claim 7, wherein the flexible fingers are inclined in a first direction, and a second set of flexible fingers are provided which are inclined in a second direction.

9. A wheel structure for use with the type of any one of claims 1 to 8, comprising a hub and spokes, the spokes having means to connect the tyre to the wheel support structure.

10. A method of manufacture of a tyre comprising the steps of:

providing an annular band which has an annular resilient web provided about its outer periphery and moulding a resilient tyre material to the band to substantially embed the flexible web within the flexible tyre material.

1 1 . A method according to claim 10, comprising the further step of

encapsulating at least a circumferential periphery of the tyre with a harder tyre material to form a tread.

12. A method according to claim 10 or 1 1 , including prior to moulding the resilient tyre material the step of forming the annular band on a wheel, the annual band providing a rim to the wheel.

13. A method according to any one of claims 10 to 12 including the step of forming on the annular band means to secure it to a wheel, the annular band providing a rim to the wheel.

14. A method according to any one of claims 10 to 13 including forming a further annular band prior to the step of moulding the resilient tyre material, which further band is concentric to the first band with the flexible web extending between the bands.

15. A method according to any one of claims 10 to 14, including the step of attaching a wear strip to the annual band to form a braking surface.

16. A method of manufacture of a wheel support for use with any one of claims 10 to 15 comprising the step of moulding a wheel support structure comprising at least a hub and spokes.

17. A method according to claim 16 in which the spokes have fixing means to selectively secure said tyre thereto.

Description:
A TYRE, A WHEEL STRUCTURE FOR USE WITH THE TYRE AND A METHOD OF MANUFACTURE OF A TYRE

The present invention relates to a tyre, and also a wheel with tyre combination.

Conventional wheels are provided with a tyre with an inner tube, or a tubeless tyre, each of which is inflated with compressed air. Whilst this type of tyre provides shock-absorbency, it has the problem that it can become flat or can burst. This is particularly problematic when used on a bicycle, because the rider needs to dismount to re-inflate the tyre and repair the puncture. Whilst using a solid tyre will prevent this problem, it will add to the weight of the bicycle and will exhibit less shock-absorbing properties. The latter can lead to any of the following: rider discomfort; the rider being thrown from the bicycle; and damage to the wheel or bicycle when the rider passes over bumps, kerbs, potholes etc.

It is an object of the present invention to provide a tyre and wheel with tyre combination which overcomes or alleviates the above described drawbacks.

In accordance with a first aspect of the present invention there is provided a tyre having a rim with the tyre material formed on the rim, wherein the rim comprises two concentric, annular bands which are interconnected by a resilient web and the tyre material comprises at least one resilient material within the web.

The web may be substantially completely encapsulated by the resilient tyre material. The tyre may comprise at least two tyre materials at least one of which is resilient. The second material may comprise a harder material which forms a tread region to the tyre. The second material may be formed on a circumferential face of the tyre, the resilient material may form side walls to the tyre.

The concentric bands may comprise an outer band and an inner band, wherein at least the outer band may be resilient. When the harder material is provided it may be formed on the outer band. The inner band may form a braking surface. The inner band may have connection means to enable placement of the tyre on a wheel.

The rim may be formed on a wheel, the rim forming the rim to the wheel.

The web may include a series of resilient fingers extending between the bands. The fingers may be preselected to provide a required cushioning effect to the wheel in use by selecting from web material, finger length, width or thickness, finger inclination or finger curvature between the bands. The resilient tyre material may be preselected to provide the required cushioning. The resilient tyre material may comprise a cellular material. In a preferred embodiment the resilient tyre material is a foam elastomer with a low density. The resilient tyre material may enable the radial flexing of the web, but substantially inhibits the flexing in a transverse direction thereto.

The flexible fingers may be inclined in a first direction and a second set of flexible fingers may be provided inclined in the opposition direction.

A wheel structure may be provided for use with the tyre comprising at least a hub and spokes, the spokes having means to connect the tyre to the wheel support structure. In accordance with a preferred embodiment a wheel is provided with a rim adapted to receive the tyre therein, the wheel rim may be selectively adjustable to enable placement of the tyre and to clamp the tyre therein.

The wheel rim may have a tapered base and a corresponding taper may be provided on the inner band of the tyre.

In accordance with a second aspect of the invention there is provided a method of manufacture of a tyre comprising providing a tyre with a rim, the rim having a resilient web, moulding a tyre material to the rim including encapsulating the web with the tyre material, the tyre material including a resilient material.

The tyre material may include a harder tyre material which forms a tread region to the tyre, the method including encapsulating at least a circumferential periphery of the tyre with the harder material.

The method may include prior to moulding the tyre with the tyre material, the step of forming the rim on a wheel.

The method may include the step of forming means on the rim to secure it to a wheel, with the annular band forming a rim to the wheel.

The method may include the step of forming a further rim on a wheel, in order to receive the tyre, the further rim being adjustable in order to retain the tyre in the further rim.

The method may include forming the rim with two concentric bands with the flexible web extending there between.

The method may include forming a wheel support for use with the tyre, comprising at least a hub and spokes, the spokes may have fixing means to selectively secure the tyre to the wheel support. The wheel has the advantage that it can flex and provide shock absorption without the need for pressurized air. In the case of a bicycle wheel this will enable the rider to pass over bumps, kerbs, potholes etc without discomfort, being dismounted or damaging the wheel or tyre. The tyres are completely puncture proof as they are produced from a cellular, or solid polyurethane, or other suitable elastomer. It also saves weight because there is no need to carry a pump and puncture repair kit. There is further weight saving in than an inner well is not required on the rim and therefore this does not need to be filled with tyre material.

Tyre centre section, full radius provides low rolling resistance.

Additional grip comes into play either when the cycle is cornering (grip section is at angle of about 15 degrees), or when on soft ground.

Under heavy cornering the outer walls of the tyre will flex to provide greater surface contact compared to a "full round" tyre. This has the effect of keeping a low profile, high contact area even when the cycle is cornering and wheel is at an angle.

The wheel is easier to change compared to standard rubber tyres (less effort).

The wheel absorbs contact with pot-holes, kerbs or other similar obstructions.

Environmentally sound: no PAH (polyaromatic hydrocarbons) and fully REACH compliant.

User does not need to carry spare, inner tube, pump or repair kit, and will only need minimal tyre change tools. PU material may have reflective and/or glow-in-dark materials dispersed within the structure.

By way of example only specific embodiments of the invention will now be described with reference to the accompanying drawings:

Fig.1 is a perspective view of a wheel before the tyre is moulded thereon;

Fig.2 is a section view a a mould used to form the tyre on the wheel of Fig.1 , showing the wheel and tyre formed thereon in accordance with a first embodiment of the present invention;

Fig.3 is a perspective view of a completed wheel with tyre constructed in accordance with the first embodiment of the invention;

Fig.4 is a perspective view of a further embodiment of wheel with a separable tyre;

Fig. 5 is a side view of the wheel or Fig. 4;

Fig. 6 is a sectional view along the line A-A of Fig. 4;

Fig. 7 is a detail of the wheel of Fig. 4; and

Fig.8 is a schematic view of a further embodiment of wheel with separable tyre.

As best illustrated in Fig.1 a wheel 2, 20 comprises a circular, disc like support structure 2 which is moulded from a suitable polymer. The wheel structure 2 comprises a rim 4, 6, 8, a central hub 10 and supporting spokes 12. The rim 4, 6, 8 forms a region on which a tyre 20 is formed.

The hub 10 forms a central axis about which the wheel 2, 20 rotates, to this end the hub 10 has an internal passage 1 1 which extends through the centre of the wheel 2, 20 to provide a central axis about which the wheel 2, 20 rotates and which provides a connection for the axle of a vehicle. The central passage 1 1 extends in a direction perpendicular to the wheel 2, 20.

The support spokes 12 extend between the rim 4, 6, 8 and the hub 10 and extend radially outwards from the hub 10 to points distributed about an internal periphery 14 of the rim 4, 6, 8. The spokes 12 connect the hub 10 to the rim 4, 6, 8 and provide strength and rigidity to the wheel 2, 20.

The rim 4, 6, 8 has two concentric, annular bands 4, 6 which are also concentric to the hub 10. A web 8 extends between the bands 4, 6. The concentric bands 4, 6 comprise an inner band 4 and an outer band 6. The inner band 4 forms the internal periphery of the rim 14. The outer band 6 forms the outermost edge 16 of the wheel 2 which extends around the outer circumference thereof.

The web 8 comprises a series of resilient fingers which extend at an inclined angle between the bands 4, 6 and are also inclined with respect to the radial direction of the wheel 2, 20. The web 8 is moulded when the wheel support structure 2 is formed, in such a manner that it is resiliently mounted between the bands 4, 6. A hollow region 7 is provided between each finger of the web 8.

The wheel 2, 20 is completed and a tyre 20 formed thereon by placing the wheel support structure 2 in a mould 16, as best illustrated in Fig.2. The mould 16 is conveniently provided in two halves 16a, 16b to enable it to be opened and the wheel support structure 2 to be laid flat on the mould 16. Each half of the mould 16 has a wheel cavity 17 which allows the wheel support structure 2 to be held snugly in the mould 16, when the two halves 16a, 16b are closed. The mould 16 also has an enlarged cavity 18 in the region of the rim 4, 6, 8. This enlarged cavity 18 forms a 'negative' for a tyre 20 which is to be moulded to the wheel support 2. The enlarged cavity 18 extends at least around the outer band 6 and the web 8.

To form the tyre 20, liquid tyre materials are introduced into the enlarged mould cavity 18 and allowed to solidify prior to the mould 16 being opened to remove the completed wheel with tyre 2, 20.

In the illustrated embodiment a tyre is formed from two different types of tyre material 20a, 20b. To this end two different types of tyre material 20a, 20b are introduced into the mould 16 in sequence.

Initially a liquid first type of tyre material 20a is introduced into the enlarged cavity 18 and the mould 16 is spun to throw this material to an outside edge of the enlarged cavity 18, which outside edge lies adjacent to the outer band 6. The outside edge of the cavity provides a 'negative' for the desired tread pattern 20a of the tyre 20. Then a second polymer 20b is introduced into the mould 16 and this fills the void areas 7 between the webs 8. This second tyre material 20b forms the side walls 20b of the tyre when it solidifies and it completely encapsulates the web 8. The quantity of first and second tyre materials 20a, 20b supplied can be pre-calculated to provide the required thickness of tread and fill the voids areas 7 of the web 8 respectively.

The first tyre material 20a is selected to provide the strength needed to provide the tread rubber around the outer circumference of the wheel 2. The second material 20b is selected to provide a resilient cushion around the flexible webs 8 and the side walls 20b of the tyre 20. In use the web 8 is designed to exhibit the desired properties. The material selected can be chosen to suit the requirements of the wheels end use. The properties include, but are not limited to the material chosen, the shape of the webs (adjusting thickness, depth and length) to change performance load, and the angle of their incline and/or curvature. The flexible web helps provide shock-absorbency, providing a smooth ride and improved durability of the completed wheel with tyre 2, 20. The provision of the second tyre material 20b which encapsulates the web 8 and fills its void areas, further enhances these advantages and helps to protect the web and to ensure that it does not exceed its elastic limit when under compression (impact), by stopping the web 8 from bottoming-out.

The second tyre material 20b can be selected from a suitable polymer such as solid polyurethane, an elastomer, or be in a cellular form; since cellular materials compress more easily than solid. It will also lose volume to a certain extent when compressed, but will return i.e. spring back when the load is removed. The second tyre material 20b also provides a flexible side wall 20b to the tyre 20, which further enhances the deforming of the wheel 2, 20 under load. It also provides support from lateral loads which the web may be subject to if the wheel 2, 20 goes over a pothole, bump, kerb etc. This type of tyre 20 is completely puncture proof since it does not contain an inner tube filled with compressed air or a tubeless tyre sealed against a rim.

The wheel support structure 2 is described as being constructed of a polyolefin, but any suitable resilient material can be used for example polyamide, polypropylene, polyethylene and polyurethane. The thickness and width of the selected materials being adjusted for the fingers of the web 8, spokes 12, hub 10, and bands 4, 6 to provide the proper support and resiliency required for those particular components. At least the outer band 6 and web 8 may require a greater degree of resiliency to enhance the flexibility of the wheel 2, 20 under load.

Whilst two tyre materials have been described, any number of tyre materials could be injected.

In a further embodiment a single tyre material is injected to provide a resilient tyre 20 which has both the tread pattern and that encapsulates the web. In this instance the second type of tyre material is 20b selected. The tread pattern could be omitted and a separate solid outer tyre applied around its circumference, to provide a harder wearing tread to the tyre. Whilst the tyre material can be introduced directly into the enlarged cavity 18 of the mould 16, this may also be introduced from the hub region 10 of the wheel support 2. To this end a cavity may be provided in the spokes 12 which enables a flow of tyre material into the enlarged cavity 18, at least one aperture may be provided in the inner band 4 to enable flow into the enlarged cavity 18. A flow channel may be provided around the inner band 4 within the cavity 17 of the mould 16 to help distribute the flow. Likewise a flow cavity may be provided in the mould cavity 17 to enable the liquid tyre material 20a or 20b to flow from the hub region 10 along the spokes 12 to the enlarged cavity 18. A residue of tyre material may solidify on the spokes 12 to enable a protective coating or shield there about. By flowing the tyre materials from the hub region a single pipe can be connected to inject the liquid tyre material, which can remain substantially static as the wheel containing mould is rotated about its central axis; thus reducing tangling.

The two tyre materials may be compatible to enable a bond or means can be provided to anchor the materials together.

The longer the web or the individual finger thereof the less stress they will experience when under compression, the length and the distance between the bands 4, 6 being selected to match the required load conditions, for example a bicycle may require longer webs than say a wheel for a wheel barrow.

By covering the fingers of the web 8 in the second tyre material, the web is kept clean from dirt and grit, which may otherwise reduce its effectiveness. A separate hub cap may be fitted over the spokes 12 to prevent dirt accumulating on the spokes 12. A hub cap can be fitted to both faces of the wheel, enabling the wheel to be used in a sterile environment. The hub cap may be flexible and may be sealed to the wheel 2, 20 by the tyre material during the tyre moulding process.

In the above described embodiment the tyre is formed directly on the wheel in order to form a complete structure. In a further embodiment the tyre section may be formed separately and means is provided to connect the tyre to the wheel support structure 2. This differs from the above in that the rim 4, 6, 8 is not formed on the spokes 12 and hub 10. The rim 4, 6, 8 and the remaining support structure 10, 12 are formed separately. The rim 4, 6, 8 is then connected to the spokes 12 and hub 10 after the tyre 20 has been formed on the rim 4, 6, 8. The tyre 20 is formed as described above, but by placing just the completed rim 4, 6, 8 within the mould 16.

The inner band 4 of the rim 4, 6, 8 is modified to include attachment means 22 for the spokes 12. This can be achieved in a number of ways. In the embodiment shown in Figs. 4, 5 and 6 the inner band 4 is formed to have a plurality of protections 22 which are evenly spaced apart around the inner periphery 14. The tip of each spoke 12, remote from the hub 10 has a corresponding circumferential groove 24 in which the projection 22 can be received. In use the tyre 20 is placed on the wheel support 10, 12 by locating the spokes 12 between the protections 22 and then simply rotating the tyre 20 in order that projections 22 engage in a respective groove 24 of a spoke 12. Each spoke 12 can then be fixed to the projection received therein to secure the tyre 20 to the wheel structure to complete the wheel 2, 20. To this end apertures 26 can be provided in each of the projections 22 and spokes 12, which when aligned can enable a bolt 28 to be placed therein and tightened. In the illustrated example there are three such apertures on each spoke 12 and projection 22.

This enables the easy replacement of a tyre 20 when it is worn, without the necessity changing the entire wheel.

In a further embodiment the tyre 20 is moulded about the rim 4, 6, 8 as described above and attached the wheel support 2 in a different manner. As best illustrated in Fig.8 the spokes 12 are moulded with a further outer rim 30 which is adapted to receive the moulded tyre 20 therein. The rim 30 provides a generally U-shaped receptacle 32 to receive the annular band 4 of the completed tyre section. The receptacle 32 has a removable wall or retainer 34 to enable the tyre section 20 to be placed and retained therein. To this end a plurality of fastening means 28 are provided around the rim 30. The fastening means 28 can be opened in order to widen the receptacle 32 by movement of the moveable wall 34. The completed moulded tyre 20 can then be placed in the receptacle 32 provided by the rim 30. The fastening means 28 are then tightened to retain the tyre 20 in the rim 30. By this means it is possible to enable an easy tyre changing procedure for when the tyre becomes worn and needs replacing. This also represents a more green solution in that it is also only necessary to replace the tyre and not the entire wheel.

The fastening means 28 includes a threaded bolt with a threaded bore 36 in the base of the rim 30 which bore extends through the rim 30 and its moveable wall 34. The threaded bore 36 can be included during the moulding of the wheel, its hub 10 spokes 12 and rim 30. The threaded bores 36 could be subsequently fitted to the completed rim 30. The bolt could be inserted and adjusted using an Allen Key or Star-Lock, enabling easy change of the tyre. Twelve such locations means may be provided, evenly distributed about the rim 30.

In a further enhancement, the base of the receptacle 30 can have a slanted surface, and a corresponding slant can be provided on the band 4 of the tyre section. By this means a tapered fit is provided between the tyre section 4, 6, 8 and the rim 30 provided around the spokes 12. This makes the fit directional. This has the advantage that the spokes 12 of the wheel can be orientated in a required direction to enhance performance or aesthetically appealing spokes could be used to enhance the appearance of the wheel, which may be orientated at an angle.

The rim 30 and tyre 20 have a matching taper when used in this type of wheel. Also, the further rim 30 could have location features that have corresponding location features on the tyre. For example the rim could have three location dogs, with three corresponding locations on the tyre.

The tyre and wheel can be further provided with an area to enabling breaking of wheel. Traditionally bicycle brakes, for example v-brakes act on the rim of the wheel. To this end the inner band 4 of the rim 4, 6, 8 is modified to include a contact area for the brake of the bicycle.

To this end inner band 4 presents a wide contacting zone for brake engagement. This is best illustrated in Fig.6, where it can be seen that the inner band 4 is formed as a box section which presents a circular area extending around each face of the wheel, 2, 20 for the brakes, and is designed to withstand the load of the brake pads. The use of a polyurethane brake pad greatly increases brake life, up to four times that of a conventional rubber pad. Furthermore, a wear strip may be added to the surface of the box section made from, for example, glass fibre filled nylon. The brake pads could be modified to include a wiper section to smooth dirt and water from the inner band's 4 surface.

The moulding stage for producing the wheel support structure 2 may be provided with an interchangeable piece in the mould in order to adapt the process to be able to produce a front wheel or rear wheel for a standard bicycle. In a front and rear wheel the width of the hub differs, therefore a changeable section to the mould to produce a desired hub for a wheel ensures that both types of wheel can be produced by the same mould.

Furthermore the area of the hub could be moulded with a recess to enable the press fit of sealed bearings. This type of bearing has a quality improvement over cone bearings and enables adaption of a standard bicycle to enable the use of the improved bearings; which exhibit less dirt ingress and therefore less wear. This type of sealed bearing with a press fit fitting enables a simple change to enable conversion of an existing bicycle to this improved system.

In addition to the above the plastics design of the wheel, the weight can be even further reduced by producing hollow spokes.

Also, although the wheel support has been described either as a one piece in the embodiment of Figs. 1 to 3 where the tyre support section, or rim 4, 6, 8 and the spokes 12 and hub 10 are moulded as a single piece, or in the embodiments of Figs. 4 to 8 where the rim section 4, 6, 8 and spokes 12 and hub 10 are moulded separately and subsequently fixed together, the support could be moulded in more sections. In this respect it is also envisaged that the wheel support structure 2 could be produced in two halves and fixed together. To this end identical mouldings can be produced and bolted together, or welded, or screwed, or glued. For example in the rim section 4, 6, 8 the web 8 is inclined for example in a clockwise direction, by securing a similar rim section 4, 6, 8 thereto the webs could also be inclined in the opposite direction. This is two sets of webs with different directions of incline. By this means it is further possible to select the desired properties of the wheel in order to enhance performance. It also enables further weight reduction in that it is easier to produce hollow spokes.

A further advantage of the moulding process is that it is possible to produce any shape to the tyre, rather than the standard semi-circular design of a standard pneumatic tyre. For example, a single circular running track 40 can extend centrally circumferentially around the wheel (see Figs. 6 and 8). This provides a resistance free ride when travelling in a straight line. Either side of the running track 40, heavy treads 42 can be provided and these can be angled away from the running track 40, in a preferred embodiment at an angle of 15° which enables them to come into play when cornering, i.e. when the cyclist leans to manoeuvre around bends. This can lead to greater performance and increased grip when required.

The tyre of the wheel in accordance with the present invention has approximately four times the life span of a standard rubber tyre. Furthermore, the provision of the flexible web which is embedded in a flexible tyre material, ensures that the wheel is not prone to puncture; whilst providing a light weight alternative to a solid tyre and with improved performance characteristics.

Many variations are possible without departing from the scope of the invention.