Method and apparatus for inspecting tires

• US 3,903,416 A
• Filed: 05/07/1973
• Issued: 09/02/1975
• Est. Priority Date: 05/07/1973
• Status: Expired due to Term

• Current Assignee: Penn Video, Inc. (Newell Brands Inc.)
• Original Assignee: Richard L.T. Fox
• Inventors: Fox, Richard L. T.
• Primary Examiner(s): Lawrence, James W.
• Assistant Examiner(s): Anderson, B. C.
• Application Number:
  US05/358,022
• Time in Patent Office: 848 Days
• Field of Search: 250/358,359,360,450
• US Class Current: 378/61
• CPC Class Codes: G01N 2223/627 tyres
• CPC Class Codes: G01N 23/083 the radiation being X-rays
• CPC Class Codes: G01N 23/185 in tyres
• CPC Class Codes: G03B 42/028 Industrial applications

Abstract

A method and apparatus for inspecting tires is disclosed wherein a tire may be completely x-rayed for constructional defects from rim to rim by use of a panoramic x-ray imaging unit which need not be manipulated during the inspection. A tire having side walls, rims and tread area extending between the side walls is supported for rotation. An x-ray source is positioned radially near the rims to direct x-rays through the side walls, rims and tread area of a circumferential section of the tire adjacent the source. A curved fluoroscopic screen is disposed about the x-ray tube focal spot and the circumferential section of the tire so that x-rays from the focal spot pass through the rims, side walls and tread area and impinge on the screen. The screen fluoresces to produce an x-ray image of the tire side walls, rims and tread area. A T.V. camera is optically coupled to the screen to view the entire screen. The image is transmitted to a T.V. monitor from which a visual inspection of the tire is made. The x-ray tube produces a wide angle beam of x-rays which simultaneously pass through all portions of the circumferential tire section and impinge on the screen across its entire surface. The T.V. camera transmits the panoramic image produced by the screen to the monitor and the tire is revolved about its axis a single time to complete the inspection.

Claims

1. In a tire inspection system for inspecting tires having side wall portions including bead rims and a tread area portion between the side wall portions:

a. tire supporting means supporting a tire in a condition wherein said side wall portions extend radially inwardly toward the tire centerline from said tread area portion;

b. radiation source means for directing tire penetrating radiation through a circumferential section of the tire including one bead rim, side wall portion and at least part of the tread area portion from a location between the tire centerline and the tread area portion, said location disposed in a first plane extending transversely to the tire centerline and between the tire side wall portions; and

, c. an inspection information producing system by which inspection information concerning the construction of a tire is obtained comprising radiation responsive imaging means and camera means;

d. said imaging means comprising;

i. an imaging member supported in the vicinity of the circumferential tire section through which radiation is directed from said source location, said member having a surface positioned with respect to said source location so that radiation passing through the circumferential tire section impinges on said member to produce a radiation stimulated image of part of the tire on said surface, said surface configured to describe a line curved generally parabolically about at least part of the circumferential section of the tire at the intersection of said surface and a second plane containing the tire centerline and extending through said source location, at least part of the tire tread area portion interposed between said source location and a first location on said imaging member surface, a tire bead rim interposed between said source location and a second location on said imaging member surface, said first and second locations disposed at different radial distances from the tire centerline and at different distances from said source location so that the image of part of the tire produced on said surface is distorted;

ii. optical coupling means between said camera means and said imaging member surface for transmitting the image on said surface to said camera means; and

, iii. structure for positioning said optical coupling means with respect to said surface so that the image transmitted to said camera means is substantially undistorted.

2. In a tire inspection system for inspecting tires having side wall portions including bead rims and a tread area portion between the side wall portions:

a. tire supporting means supporting a tire in a condition wherein said side wall portions extend radially inwardly towards the tire centerline from said tread area portion;

b. radiation source means for directing tire peneTrating radiation through a circumferential section of the tire including one bead rim, side wall portions and at least part of the tread area portion from a location between the tire centerline and the tread area portion, said radiation source means defining a focal spot at said location disposed adjacent or within a toroidal volume defined by the tire in a first plane extending transversely to the tire centerline and between the tire side wall portions with radiation from said focal spot emanating through a relatively wide angle and penetrating the adjacent circumferential section of the tire from bead rim to bead rim; and

, c. an inspection information producing system by which inspection information concerning the construction of a tire is obtained comprising radiation responsive imaging means and camera means;

d. said imaging means comprising;

i. a fluorescent screen imaging member supported in the vicinity of the circumferential tire section through which radiation is directed from said source location, said member having a surface positioned with respect to said source location so that radiation passing through the circumferential tire section impinges on said member to produce a radiation stimulated image of part of the tire on said surface, said surface defining end portions disposed on opposite sides of said first plane with the tire bead rims interposed between said focal spot and said respective end portions, said end portions extending obliquely away from said first plane and said surface configured to describe a line curved generally parabolically about said circumferential tire section and said focal spot at the intersection of said surface and a second plane containing the tire centerline and extending through said source location, at least part of the tire tread area portion interposed between said source location and a first location on said imaging member surface, a tire bead rim interposed between said source location and a second location on said imaging member surface, said first and second locations disposed at different radial distances from the tire centerline and at different distances from said source location so that the image of part of the tire produced on said surface is distorted;

ii. optical coupling means between said camera means and said imaging member surface for transmitting the image on said surface to said camera means; and

, iii. structure for positioning said optical coupling means with respect to said surface so that the image transmitted to said camera means is substantially undistorted.

3. The system claimed in claim 2 wherein said optical coupling means comprises a lens spaced from and centered with respect to said screen, said lens having a substantial depth of field for focusing said screen to said camera means regardless of the difference in distances between said lens and various locations on said screen.