GB2463323A

GB2463323A - A golf cart tyre having an array of holes between adjacent arrays of spikes

Info

Publication number: GB2463323A
Application number: GB0816851A
Authority: GB
Inventors: Nicholas Rolfe
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-09-15
Filing date: 2008-09-15
Publication date: 2010-03-17
Anticipated expiration: 2028-09-15
Also published as: GB2463323B; WO2010029319A1; GB0816851D0

Abstract

A stretchable golf cart tyre comprises at least two rows of spaced studs 4, each stud having a generally conical body with curvilinear sides extending upwards from a circular base 7 and a tip, wherein the tyre is an endless band and the studs are integrally formed by an injection moulding process, the band having a circumferential array of holes 12 positioned between the rows of studs, the hole having being generally oval with the major axis 14 substantially coincident with the central circumferential axis C of the band. The tyre is of the solid type, and the tyre apertures / holes are provided to make the tyre more flexible and easier to stretch over the rim of each wheel. The tyre is ideally made of discrete arcuate band segments joint together by ultrasonic welding, heat bonding or adhesive. Adjacent rows of spikes are preferably staggered.

Description

Vehicle Tyres This invention relates to tyres for the wheels of vehicles such as golf buggies and/or golf trolleys which are propelled either manually or under power over grassed terrains. The tyres are preferably retro-fitted to the rims of the vehicle wheels; alternatively the tyres may be permanently attached to a wheel rim. The invention further relates to a vehicle wheel manufactured to incorporate a tyre.

Many golf clubs do not allow buggies and/or trolleys to be used on fairways during wet or frosty weather because of the damage which they can cause to the fairway surface. This means that, in inclement weather, a golfer is obliged either to carry his clubs or to keep returning to his buggy or trolley parked on a pathway alongside the fairway.

Many attempts have been made to produce wheels or tyres which limit the damage which would otherwise occur to fairways and grassed areas. These have not however proved to be particularly successful. Examples of earlier proposals can be found in French Patent 502138 and EP1625027A.

Both of these documents disclose the use of cone-like studs having rounded tops which project from the surface of the outer rim of a wheel. *

One major problem with each of these proposals concerns the manner of fitting the studs to the **,** wheel rim. In FR502138, the studs are upstanding from curved tiles secured to the wheel rim. Fitting such tiles is cumbersome and time consuming. Also, the studs cannot readily be removed from the . rim of a wheel when not required. In EP1625027A, the studs are either secured to a strip of resilient * material whose ends carry fixings such as Velcro, or a continuous loop of resilient material. The *0**** * former arrangement is unsatisfactory because of the difficulty of achieving sufficient tightness of the * tyre on the wheel rim to ensure that the loop remains in place in use whereas the latter * .*...

* arrangement is unsatisfactory because of the difficulty of forcing the tyre over a wheel rim when *:*. required.

The shape and material of the studs are of course important. The Applicant has established that a generally conical shape of circular cross section and curvilinear sides leading to a relatively pointed top enables the studs to enter and grip a fairway surface and then to withdraw from the surface without causing damage to the fairway. In EP1625027A the studs are said to be parabolic in cross section or substantially so. Applicant has found that a parabolic or substantially parabolic shape is not necessary.

In one aspect, the invention provides a tyre for a golf buggy or golf trolley or like vehicle which comprises a stretchable endless band dimensioned to fit tightly over the rim circumference of each wheel of the vehicle, two or more lengthwise extending spaced rows of studs produced integrally with the band by an injection moulding process with each stud having a generally conical body with curvilinear sides extending upwardly from a circular base and terminating in a tip, the endless band including a circumferential array of holes positioned between the two rows of studs, each hole having a major axis extending substantially coincident with or parallel to the central circumferential axis of the band when fitted onto a wheel and a minor axis extending across the band width.

The lengthwise extending borders to each hole may be straight, or substantially so, and lie parallel to the longitudinal axis of the bands. The leading and trailing ends of each hole are preferably curvilinear.

The band is preferably injection moulded in discrete lengths each including at least two upstanding studs, the band lengths then being secured together at their ends by ultra sonic welding, heat bonding or by use of a suitable adhesive.

The leading and trailing ends of each band length may be shaped to define complementary steps which over or underlie the steps of adjoining band lengths.

The two rows of studs are preferably offset one from another and the spacing between neighbouring studs may be the same, or substantially the same, throughout the band length.

The leading and trailing ends of each band length is preferably set at an angle of between 55 and 65 degrees to its side edge. An angle of 59.8 degrees is preferred.

In another aspect, the invention provides a method of producing a vehicle tyre having a stretchable endless band from which are upstanding two spaced rows of generally conical studs each having curvilinear sides upstanding from a circular base and terminating in a relatively pointed tip, the method comprising injection moulding discrete band lengths including at least two studs, and ultra : * sonically welding, heat bonding or adhering the leading and trailing ends of the discrete bands together to produce a tyre of the required diameter.

In a further aspect, the invention provides a vehicle tyre of a thermoplastic elastomer or rubber * :* (referred to hereinafter as TPE), a natural or synthetic rubber or other similar flexible material from *....: which is upstanding two or more staggered circumferentially extending rows of integrally formed * studs also of a TPE, a natural or synthetic rubber or other similar flexible material, each stud having a generally conical body comprising a generally circular base, curvilinear side walls and a pointed tip.

*.*..� * S *. : Preferably, the vehicle tyre and studs are produced integrally by an injection moulding process.

* Furthermore, the vehicle tyre with upstanding studs maybe formed integrally with a wheel of the vehicle.

The invention will now be described by way of example only with reference to the accompanying diagrammatic drawings in which:-Figure 1 is a plan view from above of a section of a tyre in accordance with the invention; Figure 2 is a section taken along line "A-A" of Figure 1; and Figure 3 is an enlarged scrap view of detail "B" of Figure 2.

The illustrated tyre comprises a band 1 of a IPE, a natural or synthetic rubber or other suitable like flexible material of a length no greater than the rim diameter of the wheel to which it is to be fitted.

Upstanding from the upper surface of the band are two circumferentially extending rows 2, 3 of studs 4. The spacing between the centres 5 of each pair of studs 4 is typically between 40 and SOmms, preferably 46mm. The stud rows extend around the entire circumference of the band and are equally spaced from the two border edges of the band. The thickness of the band is typically around 2mm and its width is typically between 70 and 75 mms, preferably 73mm Each stud 4 is produced from a TPE, a natural or synthetic rubber or other suitable like material and has a circular base 7 typically of between 15 and 20mm diameter, preferably 17mm, a conical body 8 and a pointed tip 9. The height of each stud 4 above the band surface is typically 25mm. The base 7 opens onto an outwardly tapered section 11 which then blends into the conical body 8. The two stud rows are offset one from the other so that the studs of one row lie opposite land portions of the band.

Between the two rows of studs is a circumferential array of holes 12. These are positioned so that each hole of the array lies between but is spaced from the neighbouring two studs 4. The shape of each hole is important. As will be seen from Figure 1 each hole has a major axis 14 generally co incident with the central circumferential axis "C" of the band 1, and a minor axis 15 extending in a direction normal to the major axis. Typically the major axis is around 17mm and the minor axis around 15mm. The two sides 17 of each hole are straight and the leading and trailing ends 18 are curvilinear. This hole shape is important for reason that it imparts sufficient flexibility to enable the band to be stretched readily by hand to fit over the rim of a buggy wheel whilst providing tight retention of the band around a wheel rim during use. Circular holes do not impart an equivalent degree of flexibility.

: The tyre is produced by an injection moulding process in which discrete band lengths 19 carrying *. * two or more studs are sequentially produced. The individual band lengths are then secured together at their adjoining ends 21, 22 to produce the required tyre length. This method ensures that the studs 4 form integral parts of the tyre and that the material of the studs is the same as that of the band As will be seen from Figure 1, the ends 21, 22 are inclined at an angle approaching 60 degrees to the :: side edges of each band length 19. I* *

* * As is shown in Figure 3, in order to facilitate a strong connection between neighbouring band lengths 19, the leading and trailing ends of each band length are formed with steps 23, 24 which complement each other. Thus when joining neighbouring band lengths together the step 23 of one band length overlaps the step of an adjoining band length by a distance of around 12mm, the former being trapped between the step of one neighbouring band length and the studs 4 carried by that neighbouring band length.

The discrete band lengths are joined by ultra sonic welding, heat bonding or an industrial strength adhesive.

It will be appreciated that the foregoing is merely descriptive of one embodiment of the invention and that modifications can readily be made thereto without departing from the true scope of the invention as set out in the appended claims.

Claims

Claims 1. A tyre for a golf buggy or like vehicle which comprises a stretchable endless band dimensioned to fit tightly over the rim circumference of each wheel of the vehicle, two or more lengthwise extending spaced rows of studs produced integrally with the band by an injection moulding process with each stud having a generally conical body with curvilinear sides extending upwardly from a circular base and terminating in a tip, the endless band including a circumferential array of holes positioned between the rows of studs, each hole having a major axis extending substantially coincident with the central circumferential axis of the band when fitted onto a wheel and a minor axis extending across the band width.
2. A tyre as claimed in claim 1 wherein the lengthwise extending borders to each hole are straight, or substantially so, and lie parallel to the longitudinal axis of the bands.
3. A tyre as claimed in claim 2 wherein the leading and trailing ends of each hole are curvilinear.
4. A tyre as claimed in any one of the preceding claims wherein the band is injection moulded in discrete lengths each including at least two upstanding studs, the band lengths then being :. secured together at their ends by ultra sonic welding, heat bonding or by use of a suitable adhesive.
5. A tyre as claimed in claim 4 wherein the leading and trailing ends of each band length are shaped to define complementary steps which over or underlie the steps of adjoining band lengths. * .
6. A tyre as claimed in any one of the preceding claims wherein the two or more rows of studs : : are offset one from another. S. *
7. A t're as claimed in claim 6 wherein the spacing between neighbouring studs is the same,or substantially the same, throughout the band length.
8. A tyre as claimed in any one of claims 4 to 7 wherein the leading and trailing ends of each band length is set at an angle of between 55 and 65 degrees to its side edge.
9. A method of producing a vehicle tyre having a stretchable endless band from which are upstanding two or more spaced rows of generally conical studs each having curvilinear sides upstanding from a circular base and terminating in a relatively pointed tip, the method comprising injection moulding discrete band lengths including at least two studs, and ultra sonically welding, heat bonding or adhering the leading and trailing ends of the discrete bands together to produce a tyre of the required diameter.
10. A vehicle tyre of a thermoplastic elastomer, rubber or like flexible material from which are upstanding at least two staggered circumferentially extending rows of integrally formed studs also of a thermoplastic elastomer, rubber or like flexible material, each stud having a generally conical body comprising a generally circular base, curvilinear side walls and a pointed tip.