Description:FIELD OF INVENTION

The invention is relating to the invention of classic wired spoked wheels using nipples sealed at the wheel rim.

BACKGROUND OF THE INVENTION

The present invention relates to wire-spoked wheels, particularly wheels for motorcycles fitted with a tubeless tire, although the disclosure is also suitable to use on other types of wheel application. More specifically the invention relates to the rim and nipple design suitable for manufacture from steel or aluminium forming methods with a sealing device between the head of the nipple and thesurface of the rim.

A motorcycle wheel consists of a bearing carrying hub, where spokes connect the hub to the rim which provides a channel to mount a pneumatic tire. Cast or forged methods can be used to manufacture wheels with integrated spokes between the hub and rim, generally with this method the number of spokes is relatively low. Wire spoked wheels have a significantly greater number of spokes which typically have a head formed on one end and an external tread formed on the other, further, nipples with internal threads are used to generate tension in the spokes between hub and rim. Different hub and rim designs use many alternate patterns of spoke arrangement and cater for spokes to be assembled with the thread and nipple portion either at the inner hub interface or at the outer rim attachment.

Traditionally rim designs had radial apertures in the well of the rim profile arranged around the circumference, often within dimple forms in the rim to cater for the angled attachment of spokes with the nipple adjuster device located at the rim. These designs are initially assembled without a tire fitted to the rim and offer simple assembly and truing procedures with plentiful access to the nipple for tension adjustment. Typically this construction uses an inner tube to inflate the tire or some solutions exist to provide alternative rim sealing methods to realise the benefits of tubeless tires.

Wheel designs with closed rim profiles for tubeless tires are available which connect the spokes to; formed features in the rim, flange(s) or through the outer edge of the rim. These rims are generally manufactured from aluminium extrusions or forgings and as such are unsuitable for the economic requirements of a mass market cost sensitive product, particularly for regions with limited aluminium availability and processing capacity. Spoke arrangements necessary on such rim attachments, particularly to the outer edge of the rim, are not suitable for narrower wheel designs or for fitment to small capacity motorcycles with narrow suspension and brake hardware package relationships.

PRIOR ART

● JP6967103B2 - Spoke wheels and wheels

To easily fit a spoke to a rim.SOLUTION: A spoke wheel comprises: a rim 3 for supporting a tire; a hub for supporting an axle; and a plurality of spokes 6 which connects the rim 3 and the hub. The rim 3 has an open hole 10 through which a nipple 30 for connecting the spoke 6 penetrates. The spoke wheel further comprises a seal member 40 which is located in the open hole 10, and is sandwiched between the rim 3 and the nipple 30. In a cross-section view including an axial center C1 of the nipple 30, the seal member 40 has a cross section which opens in a direction parallel to the axial center C1 of the nipple 30.SELECTED DRAWING: Figure 4

● EP2368722B1 - A spoked wheel for tyres

A spoked wheel (1), including a rim (2) with a plurality of holes (21) for a respective plurality of nipples (5) fitted so as to be substantially gastight into the respective hole (21) in the rim (2) and retained in the hole (21) by means of axial bidirectional locking means (15, 36, 20), is further provided with a seal (33) between the wall of the hole (21) and a shank (13) of the nipple (5) so positioned to be subjected to a limited axial load.

● WO2019161957 - Spoked wheel for tubeless tyres

A spoked wheel for tubeless tyres is provided, with a hub and a rim, wherein a rim inner side is provided with spoke holders, which protrude inwards in a manner distributed in the circumferential direction and each have a recess, and with a plurality of spokes which extend between the hub and the spoke holders, wherein inner ends of first spokes are connected to the hub in a region on the left of a hub centre plane and inner ends of second spokes are connected to the hub in a region on the right next to the hub centre plane. In addition, outer ends of the spokes are each connected to an intermediate element which is inserted in a form-fitting manner into the recess of an associated spoke holder, wherein the intermediate elements each have a receiving recess for receiving an outer end portion of a spoke. The intermediate elements furthermore each have a substantially T-shaped cross section.

● JP4357637B2 - Spoke wheels for tubeless tires

A spoke wheel is provided which includes a hub and a rim concentric with the hub about an axis of rotation. The rim is connected to the hub by a plurality of detachable spokes. The rim has a first tubular portion, a second tubular portion, a first flange, and a second flange. The first tubular portion is arranged between the first flange and a wheel center plane which is perpendicular to the axis of rotation of the wheel. The second tubular portion is arranged between the second flange and the wheel center plane. Each of the tubular portions has an outer lateral wall having a plurality of through holes for the detachable spokes. Each of the through holes has a longitudinal axis aligned with the longitudinal axis of each of the detachable spokes.

As detailed, all of known hub and rim designs are such that spokes are assembled with thread and nipple portion either at the inner hub surface or at outer rim attachment. But suffer when applied as narrow wheel designs or when used with small capacity motorcycles.

OBJECTIVE OF THE INVENTION

The primary objective of the invention is to provide a durable motorcycle rim that is suitable for tubeless inflatable tires on a classically styled motorcycle with narrow spoke arrangement approaching the rim close to its centre plane, which is possible to manufacture using steel or aluminium rim forms.

DRAWINGS OF THE INVENTION

Figure 1 - A wheel design according to the invention; wherein the rim and hub are connected with numerous spokes with nipples sealed to the rim.

Figure 2 - A wheel design according to the invention; wherein the rim and hub are connected with numerous spokes with nipples sealed to the rim with locking nuts.

Figure 3 - Section through a nipple design according to the invention; wherein the nipple has an axial seal between the head and the rim clamped with spoke tension only.

Figure 4 - Section through a nipple design according to the invention; wherein the nipple has an axial seal between the head and the rim clamped with a retaining nut.

Figure 5 - Section through a nipple design according to the invention; wherein the nipple has an axial seal of alternate design; washer, o-ring, xring, lip seal.

SUMMARY OF INVENTION

A rim and nipple design for a wire-spoked wheel to receive an inflatable tubeless tire is provided with axially engaged sealing between the spoke head and the rim within the tire cavity. Nipples of the present invention are assembled through and the head is located in holes arranged circumferentially around the rim. Each hole is presented within a recessed dimple formed in the general radial direction inwardly from the well of the rim profile, thus providing a cupped surface for the seal interface. The nipples with an enclosed internal thread connect to the external thread of each spoke. The spokes protrude inwardly at an angle to the radial direction with an inner bend towards the hub where the head form is anchored through a hole in a conventional manner. The disclosure further relates to the application of a retaining nut onto an external thread on each nipple from the inner side providing consistent clamping across the nipple-rim interface for increased reliability of the sealing device.

DESCRIPTION OF THE INVENTION

The present invention provides a wire-spoke wheel solution to the previously described issues relating to the use of tubeless tires using a sheet metal derived rim with sealed nipples and existing spoke arrangements producing a similar design appearance to traditional wheels.

The disclosed motorcycle wheel design comprises a central hub and tire receiving rim connected with numerous wire spokes. The proposed rim has radially extending dimples protruding inwardly towards the hub which are distributed circumferentially. The outer end of each spoke has an external threaded portion to connect with nipples which have internal threads located through holes within dimples in the rim; spoke tension and wheel form are generated by tightening the nipples. The spokes extend from the rim in a general radial direction to a circumference offset from the hub where the inner ends have a bend towards the hub. The spoke ends expand at an inclination angle to a head form of larger diameter and thus anchor through locating holes countersunk and distributed around the circumference of the hub.

Leak paths between the nipple and rim are made airtight with the disclosed invention to enable the application of tubeless tyres. Nipples of the presented solution provide an annular relief in the head where it joins the stem of the nipple's main staft. Said relief groove creates a cavity to receive a sealing device which engages axially between the nipple-head and the surface of the rim within the dimple; upon installation the rim surface closes the cavity generating compression on the sealing device. The portion of the nipple head extending outboard of the relief groove has a profile which interfaces with the rim surface in a form-fitting manner. Thus locating the head of the nipple and the contact transmitting spoke tension and operating forces between the rim and hub. Further, the internal thread for spoke connection is established within a blind hole internal to the nipple shaft, thus closing the tread to the tire cavity.

The disclosed rim is provided with a curved revolution form at the root of the proposed dimples to establish a cupped surface contact for the nipple-head anchor and sealing interface. Together with apertures in the dimples, this locates and directs the nipple along the intended spoke axis. Axial sealing on the inner surface of the rim enables the rim to be constructed from sheet steel using conventional wheel rim manufacturing techniques such as; rolling and press operations. The disclosed nipple sealing device and interface design is further applicable to alternate wheel production methods such as aluminium extrusion and forging.

The proposed sealing device is located in the relief provided in the nipple head; the profile is designed to complement the shape and dimensions of the cavity formed by the groove when assembled. The pre-installed condition and dimensions of the sealing device are different to that of the final mounted state to account for the compression in the closed sealing cavity, generating pressure at the surface contact to its surroundings. The sealing device is manufactured from material substantially more compliant than the rim and nipple, elastomeric and such like materials provide the necessary contact required within the sealing cavity. The disclosure relates to the sealing device taking the simple form of a washer or O-ring and deploying a more complex section profile utilising channels and protructions from the main section. Such examples are presented with an annular channel and alternatively a lip seal protrusion at an angle between the axial and radial direction of the contact.

The disclosure further relates to a method used to produce consistent axial compression across the sealing interface. The proposed invention achieves this through the application of a retaining nut with internal thread tightened onto an external thread on the exposed surface of the nipple inside the rim clamping the surface of the rim dimple form radially adjacent to the sealing contact. Said retaining nut contact surface is presented with a form-fitting profile to match that of the hub facing surface of the rim dimple, other simpler forms of nut profile are also applicable.

The spoke arrangement is common to traditional wheel designs and could be used with existing hubs and spokes.

The manufacturing and assembly procedures are broadly similar to existing wheel designs and can be implemented with minimal impact on existing facilities.

The invention in one aspect is a design for a wire-spoked wheel to receive an inflatable tubeless tire where a sealing device is engaged in an axial direction in an enclosed cavity formed between the rim surface and the spoke nipple. The rim has dimples protruding inwardly from the annular profile in a general radial direction. The dimple surface is of curved revolution with a conical, spherical, paraboloid, hyperboloid, ellipsoid or similar shape. The head of the nipple has a form-fitting shape to the rim surface. The head of the nipple has a relief groove between the nipple-head and the main shaft. The section, size and shape are complementary to the cavity. The form is of a simple washer type, rectangular in section. The form is of a simple O-ring type, circular in section. The form is complex, using annular channels and protrusions in section. The form has a lip seal-like protrusion at an angle between the axial and radial direction as viewed from the nipple. The seal is made from elastomeric material. The seal is made from closed-pore cellulose. The nipple has both an internal thread for the spoke and an external thread. The sealed nipple to rim interface is clamped with application of a retaining nut from the inner side threaded on the nipple. The nipple has an annular depression around the main shaft. The sealed nipple to rim interface is clamped with application of a retaining spring clip on the nipple.

The invention is for a motorcycle wheel having a central hub, a rim and a plurality of wire spokes connected to rim in radial direction to a circumference offset from the hub where the inner ends have a bend towards the hub. The spoke ends expand at an inclination angle to a head form of larger diameter and thus anchor through locating holes counter sunk and are distributed around the circumference of the hub. Radially extending dimples from the rim inwardly towards the hub and arranged distributally and circumferentially and provides a cupped surface. Further each dimple has a hole. The number of nipples correspond to number of dimples arranged therein. Each spoke has external threaded portion on the outer end. And each nipple has internal threads, which correspondingly fastens onto external thread of spoke, through the holes within dimples in the rim, and holes arranged circumferentially around the rim. Further each hole has within a recessed dimple form end in the radial direction inwardly from the well of the rim profile, providing a cupped surface for the seal interface.

This arrangement is novel for the reasons that leak paths between nipple and rim are made airtight and wholly eliminated.

The nipples further provide annular relief in the head where it joins the stem of the nipple’s main shaft.

Hence the relief groove creates a cavity to receive a sealing device, which engages axially between the nipple-head and surface of the rim within the dimple, such upon installation, the rim surface closes the cavity thereby generating compression on sealing device.

The motorcycle wheel as described herein also has enclosed internal thread of nipples connect to external thread of each spoke.

The motorcycle wheel as described herein also has spokes protruding inwardly at an angle to the radial direction with an inner bend towards the hub.

The motorcycle wheel as described herein also has the head form is anchored through a hole in a conventional manner.

The motorcycle wheel as described herein also has a nut fixed on the external thread on each nipple from inner side.

BENEFITS OF THE INVENTION

Enabling tubeless tire fitment offers its own benefits relating to puncture occurrence and management and provides greater choice with increased availability of tubeless products from tire manufacturers and distributors.

Existing designs are formed using aluminium extrusions or forgings. The unique aspect of this design using axial engaged sealing enables use of rolled steel forms. This both increases the wheel durability and reduces the economic impact of using tubeless wheels on a wire-spoked wheel design. Particularly in certain economic markets and regions.

The invention has been described as detailed above but various embodiments and variations are possible beyond the preferred embodiments disclosed in this document. All such variations and modifications as obvious to the skilled person is within the scope of this invention.
, Claims:1. A motorcycle wheel having :

- a central hub,
- a rim,
- a plurality of wire spokes connected to rim in radial direction to a circumference offset from the hub where the inner ends have a bend towards the hub, and the spoke ends expand at an inclination angle to a head form of larger diameter and thus anchor through locating holes counter sunk and distributed around the circumference of the hub,
- a plurality of radially extending dimples from the rim inwardly towards the hub and arranged distributally, circumferentially, thereby providing a cupped surface, and further each dimple has a hole,
- a plurality of nipples corresponding to plurality of dimples is arranged,
- each spoke has external threaded portion on the outer end,
- each nipple has internal threads, which correspondingly fastens onto external thread of spoke, through the holes within dimples in the rim, and holes arranged circumferentially around the rim,
- each hole has within a recessed dimple form end in the radial direction inwardly from the well of the rim profile, providing a cupped surface for the seal interface, and

wherein the said arrangement is characterized such that

- leak paths between nipple and rim are made airtight,
- nipples provide annular relief in the head where it joins the stem of the nipple’s main shaft, and
- said relief groove creates a cavity to receive a sealing device, which engages axially between the nipple-head and surface of the rim within the dimple, such upon installation, the rim surface closes the cavity thereby generating compression on sealing device.

2. The motorcycle wheel as claimed in claim 1, wherein enclosed internal thread of nipples connect to external thread of each spoke.

3. The motorcycle wheel as claimed in claim 1, wherein spokes protrude inwardly at an angle to the radial direction with an inner bend towards the hub.

4. The motorcycle wheel as claimed in claim 1, wherein the head form is anchored through a hole in a conventional manner.

5. The motorcycle wheel as claimed in claim 1, wherein a nut fixed on the external thread on each nipples from inner side.