US5518055A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low resistivity tire with silica-rich tread and at least one electrostatic discharge ring
Assignee: Michelin Recherche et Technique SA Switzerland
•
Filing: 1994-09-20
•
Granted: 1996-05-21
•
Expires: 2014-09-20
Abstract
Abstract The tire of this invention has a silica-rich tread compound for excellent rolling resistance and tread wear properties. The tire is made to be conductive such that electrostatic charges on the vehicle can be quickly dissipated when the vehicle stops. An electrostatic discharge ring is located on at least one shoulder portion of the tire and has a relatively low volume resistivity, on the order of 100 megohm centimeter. The discharge ring is positioned to make contact with a conductive sidewall portion of the tire. The overall resistivity of the tire from the rim to the ground surface is made to be less than about 100 megohms.
Inventors
- 👤 Robert V. Teeple
- 👤 Sid H. Bordelon
- 👤 Dean B. Creech
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:32
CPC Classifications
B; B60; B60C; B60C19/00; B60C19/08; B60C11/00; B60C11/14; B60C11/18; Y; Y02; Y02T; Y02T10/00; Y02T10/80; Y02T10/86; Y10; Y10S; Y10S152/00; Y10S152/02
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
254 words
A radial pneumatic tire with a silica-rich tread which is capable of timely discharging the static electricity accumulated in a vehicle on which the tire is mounted, comprising: a toroidal carcass terminating at opposite bead regions of the tire which are adjacent a rim of the vehicle when the tire is mounted on the rim; a belt package radially outward of a crown portion of the carcass, and a belt edge rubber portion at each lateral edge of said belt package; a pair of spaced apart sidewall rubber portions each positioned axially outside a respective lateral portion of said carcass and extending radially inward from a respective belt edge to contact said rim when the tire is mounted on the rim; a tread portion, having at least a 50 percent silica content by weight, positioned radially outward of said belt package for contacting a ground surface over a contact patch having a tread width and supporting said tire of the vehicle; and at least one electrostatic discharge ring positioned at a lateral edge of said tread and axially inward of a respective sidewall portion and having a first edge located axially inward of a lateral edge of the tread width at a surface of the tread and a second edge located radially inward of said tread portion, wherein said at least one discharge ring provides a conductive path from the ground surface to a combination of a conductive belt edge rubber portion and a conductive sidewall rubber portion when the tire is in service.
Claim 2
Dependent Claim
254 words
A radial pneumatic tire with a silica-rich tread which is capable of timely discharging the static electricity accumulated in a vehicle on which the tire is mounted, comprising: a toroidal carcass terminating at opposite bead regions of the tire which are adjacent a rim of the vehicle when the tire is mounted on the rim; a belt package radially outward of a crown portion of the carcass, and a belt edge rubber portion at each lateral edge of said belt package; a pair of spaced apart sidewall rubber portions each positioned axially outside a respective lateral portion of said carcass and extending radially inward from a respective belt edge to contact said rim when the tire is mounted on the rim; a tread portion, having at least a 50 percent silica content by weight, positioned radially outward of said belt package for contacting a ground surface over a contact patch having a tread width and supporting said tire of the vehicle; and at least one electrostatic discharge ring positioned at a lateral edge of said tread and axially inward of a respective sidewall portion and having a first edge located axially inward of a lateral edge of the tread width at a surface of the tread and a second edge located radially inward of said tread portion, wherein said at least one discharge ring provides a conductive path from the ground surface to a combination of a conductive belt edge rubber portion and a conductive sidewall rubber portion when the tire is in service.
Claim 3
Dependent Claim
50 words
The tire set forth in claim 1, wherein said at least one electrostatic discharge ring has a relatively constant thickness value in the range of about 0.2 millimeter to about 1.0 millimeter, said at least one discharge ring being formed into lateral grooves in said tread during the curing operation.
Claim 4
Dependent Claim
31 words
The tire set forth in claim 1, wherein the electrostatic discharge ring has a rubber volume resistivity value in a range of about 10 megohm centimeter to about 100 megohm centimeter.
Claim 5
Dependent Claim
36 words
The tire set forth in claim 1 wherein the conductive sidewall rubber portion as well as the conductive belt edge rubber portion have a rubber volume resistivity value of not more than about 100 megohm centimeter.
Claim 6
Dependent Claim
56 words
The tire set forth in claim 2, wherein a first distance that the first edge of said at least one discharge ring extends axially inward from the lateral edge of the tread width is at least 7 percent of the tread width at normal vehicle operating conditions of load and pressure when said tire is new.
Claim 7
Dependent Claim
66 words
The tire set forth in claim 5, wherein the first distance the first edge of said at least one discharge ring extends radially inward from the lateral edge of the tread width is such that each discharge ring over the contact patch having the tread width has at least 15 square millimeters of area at a surface of the tread during the life of the tread.
Claim 8
Dependent Claim
54 words
The tire set forth in claim 1, wherein a second distance the second edge of said at least one discharge ring extends radially inward is a distance from the tread of at least 3 millimeters and a distance from the radially outer edge of the conductive sidewall rubber portion of at least 20 millimeters.
Claim 9
Dependent Claim
58 words
The tire set forth in claim 1, wherein there are two electrostatic discharge rings each positioned at a respective lateral edge of said tread and having a relative constant thickness value in the range of about 0.2 millimeter to about 1.0 millimeter, said discharge rings being formed into lateral grooves of the tread during the tire's curing operation.
Claim 10
Dependent Claim
32 words
The tire set forth in claim 8, wherein the electrostatic discharge rings each have a rubber volume resistivity value in a range of about 10 megohm centimeter to about 100 megohm centimeter.
Claim 11
Dependent Claim
53 words
The tire set forth in claim 9, wherein a first distance the first edge of each discharge ring extends axially inward of a respective lateral edge of the tread width is at least 7 percent of the tread width at normal vehicle operating conditions of load and pressure when the tire is new.
Claim 12
Dependent Claim
64 words
The tire set forth in claim 10, wherein the first distance the first edge of each discharge ring extends axially inward of a respective lateral edge of the tread width is such that each discharge ring over the contact patch having the tread width has at least 15 square millimeters of area at a surface of the tread during the life of the tread.
Claim 13
Dependent Claim
70 words
The tire set forth in claim 9, wherein a second distance the second edge of each discharge ring extends radially inward is a distance from the tread of at least 3 millimeters and a distance from the radially outer edge of the respective conductive sidewall rubber portion of at least 20 millimeters, the respective conductive sidewall rubber portion having a volume resistivity of not more than about 100 megohm centimeter.
Claim 14
Dependent Claim
34 words
The tire set forth in claim 1, wherein the overall resistance of the tire from the rim to the ground surface when the tire is in service is not greater than about 100 megohms.
Claim 15
Dependent Claim
34 words
The tire set forth in claim 8, wherein the overall resistance of the tire from the rim to the ground surface when the tire is in service is not greater than about 100 megohms.
References Cited (Backward Citations)
US2339546A
Cited
US1797545A
Cited
US1945283A
Cited
FR793507A
Cited
US2441945A
Cited
US2290670A
Cited
US2329332A
Cited
US2267503A
Cited
US2316549A
Cited
GB554216A
Cited
US2342576A
Cited
US2324589A
Cited
US2475119A
Cited
FR936583A
Cited
US2521305A
Cited
US2650641A
Cited
US2641294A
Cited
US2930426A
Cited
FR1251273A
Cited
FR1251453A
Cited
US3217824A
Cited
FR1546488A
Cited
JPS54102711A
Cited
JPS558929A
Cited
JPS5551606A
Cited
JPS56112306A
Cited
JPS56131407A
Cited
JPS57147903A
Cited
JPS57194109A
Cited
US4519430A
Cited
JPS61122002A
Cited
JPS61122003A
Cited
JPS61143203A
Cited
US5066721A
Cited
JPH0193094A
Cited
JPH01293208A
Cited
US5173135A
Cited
JPH0342312A
Cited
JPH0374202A
Cited
US5227425A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-05-21 | 1999-11-20 | 2000-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-05-21 | 2003-11-20 | 2004-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-05-21 | 2007-11-20 | 2008-05-21 | $7700.00 | Window Closed / Lapsed |