Method of and apparatus for determining geometrical dimensions of a vehicle wheel

• US 7,768,632 B2
• Filed: 05/23/2008
• Issued: 08/03/2010
• Est. Priority Date: 05/23/2007
• Status: Active Grant

• Current Assignee: Snap-On Equipment S.r.l. (Snap-On Incorporated)
• Original Assignee: Snap-On Equipment S.r.l. (Snap-On Incorporated)
• Inventors: Sotgiu, Paolo
• Primary Examiner(s): ALSOMIRI, ISAM A
• Application Number:
  US12/126,368
• Publication Number:
  US 20080297777A1
• Time in Patent Office: 802 Days
• Field of Search: 356/139.09, 356/155, 301/5.21, 73460-462
• US Class Current: 356/139.09
• CPC Class Codes: B60C 25/0527 Adapting to different wheel diameters, i.e. distance between support and tool
• CPC Class Codes: B60C 25/0554 optical, e.g. cameras
• CPC Class Codes: B60C 25/138 with rotary motion of tool or tyre support
• CPC Class Codes: G01B 11/245 using a plurality of fixed, simultaneously operating transducers G01B11/2408 - G01B11/2425, G01B11/255 take precedence
• CPC Class Codes: G01B 11/2513 with several lines being projected in more than one direction, e.g. grids, patterns
• CPC Class Codes: G01M 17/013 Wheels
• CPC Class Codes: G05B 2219/37048 Split beam, stripe projection on object, lines detected with cameras

Abstract

A method and an apparatus of determining geometrical dimensions of a motor vehicle wheel (rim/tire assembly) 1 by contact-less sensing, wherein the wheel is fixed on wheel receiving means 2 of a tire changer, that at least one light beam 21 is emitted on to the wheel or at least a part of the wheel, wherein the light beam reflected at the impingement area is detected, and wherein the directions of the emitted and reflected light beams are evaluated for determining the shape and/or position of the respective impingement area on the wheel.

Claims

1. A method of fitting or removing a motor vehicle tire comprising the steps of:

fixing a rim of a motor vehicle wheel rim/tire assembly on wheel receiving means of a tire changer, the wheel having two rim beads;

determining geometrical dimensions of the wheel by contactless sensing, wherein at least one planar light beam is emitted onto at least one rim bead of the wheel, the at least one light beam reflected at a stripe-shaped impingement area on the wheel is detected, and directions of the emitted and reflected light beams are evaluated for determining the shape and/or position of said impingement area on the wheel,

guiding the movement of a fitting or removal tool in dependence of the determined geometrical dimensions of the at least one rim bead, and

at least one planar light beam is emitted from a stationary position, wherein a rim contour along which the fitting or removal tool is guided during the fitting or removal operation is determined from the stripe-shaped impingement area, and the movement of the fitting or removal tool is guided in dependence on the determined contour without contact with a rim surface.

2. The method according to claim 1,

Wherein the at least one light beam is directed onto the wheel or onto the rim which is rotated about a stationary axis.

3. The method according to claim 1,

wherein an outer peripheral surface of the rim is sensed with the planar light beam.

4. The method according to claim 1,

wherein spacings of the rim beads which are sensed by the planar light beam relative to a stationary reference are ascertained.

5. The method according to claim 4,

wherein the ascertaining of the spacings is effected in accordance with a triangulation method.

6. The method according to claim 1,

wherein respective emitted and reflected light beams associated with a plurality of impingement points of the stripe-shaped impingement area are detected and the positions of the respective impingement points are determined.

7. The method according to claim 1,

wherein the movement of the at least one fitting or removal tool is controlled in dependence on a sensed position of the at least one rim bead and in dependence on the stored or sensed contour of a rim bed.

8. The method according to claim 1,

wherein the movement on the at least one fitting or removal tool is controlled in dependence on the detected position of an outer peripheral edge of the at least one rim bead.

9. The method according to claim 1,

wherein the emitted light beam is a single linear beam which is swiveled in a plane.

10. Use of a method according to one of claims 1 to 9 for determining at least one of the parameters:

tire runout, tread wear of the tire, tire conicity, tire defects on the tread and/or on the side walls, rim defects on the outside and/or on the inside of the rim and bead seat geometry on the rim.

11. An apparatus for fitting or removing a motor vehicle tire comprising a rotatably supported wheel receiving device to which a wheel having two rim beads or a rim is to be fixed;

at least one fitting or removal tool;

a rotary drive device for the wheel receiving device;

a sensing device for sensing a radially outer contour,

wherein the sensing device has at least one light source which emits a planar light beam from at least one given position onto at least one rim bead, and a detector which detects the direction of the light beam reflected from a stripe-shaped impingement area on the wheel surface;

a computer-aided evaluation arrangement for evaluation of electrical sensing signals supplied by the sensing device being suitable for determining a shape and/or position of the sensed wheel surface; and

a control device which is connected to the evaluation arrangement to control the movement of the at least one fitting or removal tool in the fitting or removal operation in dependence of the sensing signals,

wherein the at least one light source and the detector are positioned stationary,

wherein the evaluation arrangement is suitable for determining from the stripe-shaped impingement area a rim contour along which the at least one fitting or removal tool is to be guided during the fitting or removal operation, and

wherein the control device is configured to control the at least one fitting or removal tool in the fitting or removal operation in dependence on the determined rim contour without contact with the rim surface.

12. The apparatus according to claim 11,

wherein at least one light source and an associated detector are provided as the sensing device for sensing an outside surface of the rim or of the wheel.

13. The apparatus according to claim 11,

wherein the light source and the detector are pivotable synchronously about a common axis for emitting a single light beam in a planar plane and an electrical signal proportional to the respective pivot angle is fed to the evaluation arrangement.

14. The apparatus according to claim 11,

wherein the evaluation arrangement is suitable for determining positions of respective locations which are sensed on the wheel surface or on the rim surface from the directions of the light beam emitted by the light source and the light beam reflected at the wheel surface or the rim surface by means of triangulation.

15. The apparatus according to claim 11,

wherein the wheel or the rim is mounted on a wheel receiving device rotatably about an axis of the wheel.

16. The apparatus according to claim 11,

wherein a rotary angle sensor detects a respective rotary angle position of the wheel or the rim and supplies a corresponding electrical signal to the evaluation arrangement.

17. The apparatus according to claim 11,

wherein the sensing device is arranged in front of the at least one fitting or removal tool in a direction of rotation of the wheel receiving device.

18. The apparatus according to claim 11,

wherein the sensing direction of the sensing device is approximately parallel to a rotation axis of the wheel or the rim.

19. The apparatus according to claim 11,

wherein spatial positions of the respectively sensed points on the wheel or the rim are determined with respect to the fitting or removal tool.

20. The apparatus according to claim 11,

wherein the evaluation arrangement is designed to determine a respective spatial position of outer peripheral edges of the rim beads.

21. The apparatus according to claim 11,

wherein the evaluation arrangement is suitable for determining the spatial position of a rim bed which is between the rim beads.

22. The apparatus according to claim 11,

wherein for different wheel types, contours of the rim beads are stored in a database of the control device or in a database connected to the control device.

23. The apparatus according to claim 11,

wherein contours of the rim beads are stored in a database.

24. The apparatus according to claim 11,

wherein for different wheel types features of the wheels are stored in a database of the control device.

25. The apparatus according to claim 11,

wherein the light source is a laser.

26. The apparatus according to claim 11,

wherein the detector comprises a complementary metal oxide semiconductor (CMOS) device or a charge coupled device (CCD).