US3661014A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for determining irregularities in the behavior of tires rotating under load
Assignee: Industrie Pirelli SpA
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Filing: 1970-04-15
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Granted: 1972-05-09
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Expires: 1990-04-15
Abstract
Abstract The disclosure includes a method and apparatus for determining the maximum variation of the rolling radius and the slip angle during each turn of an automotive tire rotating under load. In the method, the tire under test and a rigid surface having an axis parallel to the tire axis are brought into contact and are mutually compressed by application of an elastic pressure, the cylindrical surface being capable of oscillating about at least one axis lying in its median plane and disposed perpendicular to the axis of the cylindrical surface; the tire and the cylindrical surface are oppositely rotated by controlling the rotation of one or the other; and the angular displacements of the axis of the cylindrical surface about the axis of oscillation, which are caused by variations of the lateral thrust during each turn of the tire in the zone of contact between the tire and the adjacent surface, are then determined. The apparatus comprises a rigid cylinder rotatable about an associated shaft and capable of oscillating about an axle lying in its median plane and disposed perpendicular to the shaft. Such apparatus also includes an element adapted to produce elastic compression between the tire and cylinder and means for determining the angular displacements of the axis of the shaft about the axis of oscillation, which displacements are caused by variations of the lateral thrust which occurs during each turn of the tire in the region of contact between the cylinder and tire as they are oppositely rotated.
Inventors
- 👤 Valerio Ciampolini
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 02:28
CPC Classifications
B; B29; B29D; B29D30/00; B29D30/06; B29D30/0601; B29D30/0633; G; G01; G01M; G01M17/00; G01M17/007; G01M17/02; G01M17/022
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
141 words
A method for determining irregularities in the behavior of tires rotating under load, comprising placing the periphery of the tire under test in contact with a rigid cylindrical surface with the axis of said cylindrical surface parallel to the tire axis compressing said tire against said surface by application of an elastic pressure therebetween, said cylindrical surface being adapted to oscillate about at least an axis lying in its median plane and perpendicular to the axis of said surface, placing the tire and said cylindrical surface into rotation in opposite sense by controlled rotation of one of the two, and determining the angular displacements of the axis of said cylindrical surface about said axis of oscillation, resulting from variations of the lateral thrust, during each turn of the tire, in the zone of contact of the tire with said cylindrical surface.
Claim 2
Independent Claim
141 words
A method for determining irregularities in the behavior of tires rotating under load, comprising placing the periphery of the tire under test in contact with a rigid cylindrical surface with the axis of said cylindrical surface parallel to the tire axis compressing said tire against said surface by application of an elastic pressure therebetween, said cylindrical surface being adapted to oscillate about at least an axis lying in its median plane and perpendicular to the axis of said surface, placing the tire and said cylindrical surface into rotation in opposite sense by controlled rotation of one of the two, and determining the angular displacements of the axis of said cylindrical surface about said axis of oscillation, resulting from variations of the lateral thrust, during each turn of the tire, in the zone of contact of the tire with said cylindrical surface.
Claim 3
Dependent Claim
83 words
A method according to claim 1, in which the cylindrical surface is adapted to oscillate also about an axis lying in a plane perpendicular to said first axis of oscillation and passing through a diametrical plane of said cylindrical surface, evaluating the angular displacements of the axis of said cylindrical surface about said second axis of oscillation, resulting from the variations of the rolling radius during each turn of the tire, and determining the mutual compression between the tire and said cylindrical surface.
Claim 4
Dependent Claim
53 words
A method according to claim 1, in which the angular displacements of the axis of said cylindrical surface about each of said axes of oscillation are determined by evaluating the angular displacements of a plane passing through the axis of the oscillation in question and integral with the axis of the cylindrical surface.
Claim 5
Independent Claim
134 words
An apparatus for determining irregularities in the behavior of tires rotating under load which comprises: a rigid cylinder rotatably mounted on a shaft and adapted to oscillate at least about an axis lying in its median plane and perpendicular to the shaft of said cylindr,means for rotably mounting a tire to be tested, means for producing an elastic compression between said rigid cylinder and said tire to be tested, means for simultaneously rotating said tire in one direction and said cylinder in the opposite direction, and means for measuring the angular displacements of the shaft of said cylinder about said axis of oscillation, during rotation of said cylinder which are caused by variations of the lateral thrust, during a turN of the tire, at the compression zone between said tire and said rigid cylinder.
Claim 6
Independent Claim
134 words
An apparatus for determining irregularities in the behavior of tires rotating under load which comprises: a rigid cylinder rotatably mounted on a shaft and adapted to oscillate at least about an axis lying in its median plane and perpendicular to the shaft of said cylindr,means for rotably mounting a tire to be tested, means for producing an elastic compression between said rigid cylinder and said tire to be tested, means for simultaneously rotating said tire in one direction and said cylinder in the opposite direction, and means for measuring the angular displacements of the shaft of said cylinder about said axis of oscillation, during rotation of said cylinder which are caused by variations of the lateral thrust, during a turN of the tire, at the compression zone between said tire and said rigid cylinder.
Claim 7
Dependent Claim
87 words
An apparatus according to claim 4, in which the rigid cylinder is also adapted to oscillate about an axis lying in a plane perpendicular to said first axis of oscillation and passing through a diametrical plane of said cylindrical surface, and having means for determining the angular displacements of the shaft of said cylinder about said second axis of oscillation, caused by variations of the rolling radius of the tire during each turn of the latter, at the compression zone of said tire and said rigid cylinder.
Claim 8
Dependent Claim
116 words
An apparatus according to claim 5, in which the shaft for the rigid cylinder is supported by a balance, said balance comprising two rods, each terminal face of which is in contact with and freely oscillatable upon a ball inserted in a seat at one end of the cylinder shaft and in two levers each having its fulcrum on a fixed pivot, freely rotatable and parallel to the cylinder shaft, and by a ledger parallel to said pivot and rotatably assembled at its ends in two oscillating supports sustained by said lever, and the means for producing said elastic compression comprising a helical spring having one end thereof fixed at the middle portion of said ledger.
Claim 9
Dependent Claim
30 words
An apparatus according to claim 6, in which the shaft of the rigid cylinder is connected by means of a frame to a vertical shaft constituting said axis of oscillation.
Claim 10
Dependent Claim
36 words
An apparatus according to claim 7, in which the frame comprises two pairs of thin rods which, starting from the opposite ends of said vertical shaft, spread out to reach the supports of the cylinder shaft.
Claim 11
Dependent Claim
42 words
An apparatus according to claim 7, in which the fixed pivot on which the levers of the balance are fulcrumed is supported at its ends by a box which is adapted for movement toward and away from the tire to be tested.
Claim 12
Dependent Claim
23 words
An apparatus according to claim 9, in which said box is rotatably assembled on a shaft parallel to the shaft supporting the cylinder.
Claim 13
Dependent Claim
36 words
An apparatus according to claim 9, in which the end of the spring which is opposite to that connected to the balance is fixed to said box through a means adapted to vary its axial position.
Claim 14
Dependent Claim
35 words
An apparatus according to claim 11, in which means are provided for preventing rotation of the spring about its own axis during the adjustment of the axial position of its end fixed to the box.
Claim 15
Dependent Claim
39 words
An apparatus according to claim 9 in which the box is mounted upon a table and a plurality of interchangeable columns of different heights are provided supporting said table at different vertical positions above the base of the apparatus.
Claim 16
Dependent Claim
24 words
Apparatus according to claim 13, in which means are provided for adjusting the distance between said table and said base during changes in columns.
Claim 17
Dependent Claim
27 words
An apparatus according to claim 5, in which a shaft rotatably mounted at its ends within supports integral with the box, constitutes the second axis of oscillation.
Claim 18
Dependent Claim
77 words
An apparatus according to claim 6, in which means are provided for recentering the rigid cylinder when it is brought out of its equilibrium position in consequence of an angular displacement about its first axis of oscillation comprising two elements having V-shaped surfaces, each of which is rigidly affixed to one of the supports of the shaft of the rigid cylinder, and a small rod, cooperating with each of said surface and rotatably assembled on said box.
Claim 19
Dependent Claim
29 words
An apparatus according to claim 16, in which the small rolls constitute also means for limiting the oscillation of the rigid cylinder in the direction of the compression thrust.
Claim 20
Dependent Claim
165 words
An apparatus according to claim 5, in which the means for measuring the angular displacements of the shaft of said cylinder about at least one of said axes of oscillation are constituted by devices, comprising a feeling shank adapted to move axially in both directions independently of or jointly with a coaxial rod adapted to move axially within two pre-established limits, to originate the displaceMent of a pointer, with respect to a base value corresponding to one of said limits, a friction element adapted to resist the independent movement of said shank and of said rod, a first elastic element urging said rod toward the feeling shank, a second elastic element acting on said shank to detach it from the rod, the resistance to said independent movement of the feeling shank and of the rod being always greater than the thrust exerted by said first elastic element on said rod and always smaller than the thrust exerted by said second elastic element on said stem.
Claim 21
Dependent Claim
56 words
An apparatus according to claim 18, in which, for each device determining the oscillations of the shaft of the rigid cylinder about one of said axes of oscillation, provision is made of a plane integral with said shaft, passing through said axis of oscillation and perpendicular to the feeling shank with which it is in contact.
Claim 22
Dependent Claim
42 words
An apparatus according to claim 19, in which the devices for determining the oscillations of the shaft of the rigid cylinder about said axes of oscillation are integrally mounted on said box and have their feeiling shanks arranged perpendicularly to said planes.
Claim 23
Dependent Claim
82 words
An apparatus according to claim 18, in which means are provided for rotating the box about said shaft in a direction approaching the tire to be tested, and then for rotating the box in the opposite direction by an angle corresponding to a lowering of it of the order of magnitude of the stroke between the two limits of the rods of the device for determining the angular displacements of the shaft of the rigid cylinder about the second axis of oscillation.
Claim 24
Dependent Claim
77 words
An apparatus according to claim 18, in which means are provided for maintaining the rigid cylinder, while it is in rest position, rotated about the first axis of oscillation by an angle corresponding to an axial displacement of the feeling shank of the device for determining the angular displacements of the shaft of the rigid cylinder about the first axis of oscillation, of the order of magnitude of the stroke between said two limits of said device.
Claim 25
Dependent Claim
45 words
An apparatus according to claim 22, in which the means for maintaining the rigid cylinder rotated about the first axis of oscillation while it is in rest position comprises a fixed cam cooperating with a small roll supported by the shaft of the rigid cylinder.
Claim 26
Dependent Claim
25 words
An apparatus according to claim 23, in which said cam is integral with a table, which supports the shaft on which the box is pivoted.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-09 | 1975-11-08 | 1976-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-09 | 1979-11-08 | 1980-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-09 | 1983-11-08 | 1984-05-09 | $7700.00 | Window Closed / Lapsed |