GB2030938A

GB2030938A - Tyre tread cover

Info

Publication number: GB2030938A
Application number: GB7926911A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1978-09-30
Filing date: 1979-08-02
Publication date: 1980-04-16

Abstract

A motor vehicle tyre 1 with side walls 6 has a tread part 8 over which is fitted a separate cover 10 of rubber compound, which may be reinforced by textile thread or metal wire. The cover has a ground contacting part 12 with a tread pattern, and side walls 14 incorporating substantially inextensible annular metal reinforcements 16 and overlying part of the tyre side walls. Studs 18, e.g. of steel or nylon, project from the part 12. The cover is particularly intended for use in conditions of ice, snow or mud, and can be fitted onto the deflated tyre which is then reflated to hold the cover. <IMAGE>

Description

SPECIFICATION Tread cover This invention relates to a tread cover for a motor vehicle tyre and also concerns a method of covering the tread of such a tyre.

According to one aspect of the invention a thread cover for a motor vehicle tyre comprises an annulus comprising rubber material, said annul us having a channel-shaped cross-section in which a first part of the annulus forming the base of the channel is a ground running part intended to overlie and extend around tread of the vehicle tyre on which the cover is to be fitted, and second parts of the annulus forming sides of the channel being intended to overlie sides of the tyre.

According to a second aspect of the invention a method of covering the tread of a motor vehicle tyre comprises providing a cover formed according to the first aspect of the invention in which the first part has a diameter substantially similar to that of the tyre to be covered with said tyre in at least a partially de-flated state fitting the cover on the tyre such that said first part of the annulus overlies and extends around the tyre tread and the second parts of the annulus overlie sides of the tyre, and inflating the tyre so that surfaces of the tyre tread and sides of the tyre are pressed firmly by air pressure against inner surfaces of the annulus to hold the cover in position.

The tyres to be covered can be tubeless tyres or tyres supported in an inflated state by inner tubes.

The rubber material from which the cover is formed can be of any known type from which vehicle tyres are constructed. The cover may be re-inforced by textile thread or metal wire in a manner known per se in the tyre industry.

The ground running part of the cover may have a tread pattern formed in the outer surface of the first part of the annulus.

The first part of the annulus may have studs projecting from the outer surface of the said first part. Preferably, these studs are of hard wearing material which may be metal, for example steel, or plastics, for example nylon. A vehicle having its tyres fitted with such studded covers has improved grip in conditions of ice and snow. Such covers are relatively easy to fit and have the advantage over known snow chains in that the covers make less noise, are liable to cause less damage to the vehicle, protect the tread of the tyre during skidding, and the tight fit between the cover and inflated tyre reduces the chance of relative movement between the tyre and cover and so reduces the chance of the tread of the tyre being damaged. When chains are used the tyre tread can become scored.

Furthermore, a studded cover can give improved traction to vehicles having to travel on mud roads or over fields such as on farms and estates.

Covers without studs can be used on the tyres of vehicles travelling normal roads, to avoid wear of tyre tread.

The second parts of the annulus forming sides of the cover can extend someway over the side walls of the tyre to protect them.

Preferably the free peripheries of the side parts of the annulus (i.e. the peripheries remote from the first part) are re-inforced by substantially inextensible annuli of, for example, metal wire or strip. This ensures secure holding of the free ends of the peripheries against the inflated tyre and resists transverse slip of the cover relatively to the tyre.

The studs may have shanks with an enlarged head at one end. Each shank passes through the first part of the annulus so that the head is adjacent the inner surface of the first part and the free end or tip of the shank projects beyond the outer surface. The heads are thus held firmly captive between the inner surface of the annulus and the thread of the inflated tyre.

The invention will now be further described by way of example with reference to the accompanying informal drawings in which: Fig. 1 shows in cross-section a vehicle wheel having a tyre on which is fitted a cover according to the first aspect of the invention by the method according to the second aspect; Fig. 2 is a fragmentary view on a reduced scale of the cover and tyre in Fig. 1 , and Fig. 3 is an enlarged perspective view of a stud.

In the drawing, a vehicle wheel is shown at? having a conventional tyre 4 with side alls 6 and a tread 8.

An annular cover 10 comprising rubber tyre compound is of a channel shaped section the base of which is a ground running or tread part 12 of the cover and the sides of which channel are annular side walls 14 of the cover. The free annular peripheries of the walls 14 are re-inforced by substantially inextensible metal annuli 1 6.

The side walls 14 extend over shoulders 8a of the tyre between the tread 8 and side walls 6 and overlie part of the side walls 8.

As shown in Fig. 1, outer surfaces of the inflated tyre 4 firmly press and grip against the inner surfaces of the cover to securely hold the cover in place.

The outer surface of the part 12 can be formed with a tread pattern.

The cover can be provided with studs having shanks 1 8 passing through the ground running part 12 and enlarged heads 20 pressed against the inner surface of the ground running part by the tyre tread 8.

The tyre 4 is first at least partially deflated to soften it sufficiently to allow the cover 10 to be fitted over the tread 8, and then the tyre is reflated to hold the cover. The cover is removable after deflating the tyre.

1. A tread cover for a water vehicle tyre comprising an annulus comprising rubber material, said annulus having a channel-shaped cross-section in which a first part of the annulus forming the base of the channel is a ground running part intended to overlie and extend around

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Tread cover This invention relates to a tread cover for a motor vehicle tyre and also concerns a method of covering the tread of such a tyre. According to one aspect of the invention a thread cover for a motor vehicle tyre comprises an annulus comprising rubber material, said annul us having a channel-shaped cross-section in which a first part of the annulus forming the base of the channel is a ground running part intended to overlie and extend around tread of the vehicle tyre on which the cover is to be fitted, and second parts of the annulus forming sides of the channel being intended to overlie sides of the tyre. According to a second aspect of the invention a method of covering the tread of a motor vehicle tyre comprises providing a cover formed according to the first aspect of the invention in which the first part has a diameter substantially similar to that of the tyre to be covered with said tyre in at least a partially de-flated state fitting the cover on the tyre such that said first part of the annulus overlies and extends around the tyre tread and the second parts of the annulus overlie sides of the tyre, and inflating the tyre so that surfaces of the tyre tread and sides of the tyre are pressed firmly by air pressure against inner surfaces of the annulus to hold the cover in position. The tyres to be covered can be tubeless tyres or tyres supported in an inflated state by inner tubes. The rubber material from which the cover is formed can be of any known type from which vehicle tyres are constructed. The cover may be re-inforced by textile thread or metal wire in a manner known per se in the tyre industry. The ground running part of the cover may have a tread pattern formed in the outer surface of the first part of the annulus. The first part of the annulus may have studs projecting from the outer surface of the said first part. Preferably, these studs are of hard wearing material which may be metal, for example steel, or plastics, for example nylon. A vehicle having its tyres fitted with such studded covers has improved grip in conditions of ice and snow. Such covers are relatively easy to fit and have the advantage over known snow chains in that the covers make less noise, are liable to cause less damage to the vehicle, protect the tread of the tyre during skidding, and the tight fit between the cover and inflated tyre reduces the chance of relative movement between the tyre and cover and so reduces the chance of the tread of the tyre being damaged. When chains are used the tyre tread can become scored. Furthermore, a studded cover can give improved traction to vehicles having to travel on mud roads or over fields such as on farms and estates. Covers without studs can be used on the tyres of vehicles travelling normal roads, to avoid wear of tyre tread. The second parts of the annulus forming sides of the cover can extend someway over the side walls of the tyre to protect them. Preferably the free peripheries of the side parts of the annulus (i.e. the peripheries remote from the first part) are re-inforced by substantially inextensible annuli of, for example, metal wire or strip. This ensures secure holding of the free ends of the peripheries against the inflated tyre and resists transverse slip of the cover relatively to the tyre. The studs may have shanks with an enlarged head at one end. Each shank passes through the first part of the annulus so that the head is adjacent the inner surface of the first part and the free end or tip of the shank projects beyond the outer surface. The heads are thus held firmly captive between the inner surface of the annulus and the thread of the inflated tyre. The invention will now be further described by way of example with reference to the accompanying informal drawings in which: Fig. 1 shows in cross-section a vehicle wheel having a tyre on which is fitted a cover according to the first aspect of the invention by the method according to the second aspect; Fig. 2 is a fragmentary view on a reduced scale of the cover and tyre in Fig. 1 , and Fig. 3 is an enlarged perspective view of a stud. In the drawing, a vehicle wheel is shown at? having a conventional tyre 4 with side alls 6 and a tread 8. An annular cover 10 comprising rubber tyre compound is of a channel shaped section the base of which is a ground running or tread part 12 of the cover and the sides of which channel are annular side walls 14 of the cover. The free annular peripheries of the walls 14 are re-inforced by substantially inextensible metal annuli 1 6. The side walls 14 extend over shoulders 8a of the tyre between the tread 8 and side walls 6 and overlie part of the side walls 8. As shown in Fig. 1, outer surfaces of the inflated tyre 4 firmly press and grip against the inner surfaces of the cover to securely hold the cover in place. The outer surface of the part 12 can be formed with a tread pattern. The cover can be provided with studs having shanks 1 8 passing through the ground running part 12 and enlarged heads 20 pressed against the inner surface of the ground running part by the tyre tread 8. The tyre 4 is first at least partially deflated to soften it sufficiently to allow the cover 10 to be fitted over the tread 8, and then the tyre is reflated to hold the cover. The cover is removable after deflating the tyre. CLAIMS

1. A tread cover for a water vehicle tyre comprising an annulus comprising rubber material, said annulus having a channel-shaped cross-section in which a first part of the annulus forming the base of the channel is a ground running part intended to overlie and extend around tread of the vehicle tyre on which the cover is to be fitted, and second parts of the annulus forming sides of the channel being intended to overlie sides of the tyre.

2. A tread cover as claimed in claim 1, in which each second part is provided with a substantially inextensible re-inforcement extending around the second part.

3. A tread cover as claimed in claim 2, in which the re-inforcement is metal wire or strip.

4. A tread cover as claimed in any preceding claim in which the ground running part of the cover has an outer surface formed with a tread pattern.

5. A tread cover as claimed in any preceding claim having studs projecting from the outer surface of the ground running part.

6. A tread cover as claimed in claim 5, in which the studs are of metal or plastics.

7. A tread cover as claimed in claim 5 or claim 6, in which said studs extend through said ground running part and have heads adjacent an inner surface of the ground running part

8. A method of covering the tread of a motor vehicle tyre comprising providing a cover as claimed in any preceding claim in which the first part has a diameter substantially similar to that of the tyre to be covered, with said tyre is at least a partially de-flated state fitting the cover on the tyre such that said first part of the annulus over lies and extends around the tyre tread and the second parts of the annulus overlie sides of the tyre, and inflating the tyre so that surfaces of the tyre tread and sides of the tyre are pressed firmly by air pressure against inner surfaces of the annulus to hold the cover in position.

9. A tread cover for a motor vehicle tyre, substantially as hereinbefore described with reference to the accompanying drawing.

1 0. A method of covering the tread of a motor vehicle tyre, substantially as hereinbefore described with reference to the accompanying drawing.