Vehicle wheel alignment apparatus

• US RE33,144 E
• Filed: 11/22/1982
• Issued: 01/09/1990
• Est. Priority Date: 10/02/1979
• Status: Expired due to Term

• Current Assignee: Hunter Engineering Company
• Original Assignee: Hunter Engineering Company
• Inventors: Hunter, Lee, January, Daniel B.
• Primary Examiner(s): Buczinski, Stephen C.
• Application Number:
  US06/443,381
• Time in Patent Office: 2,605 Days
• Field of Search: 356/152, 356/155, 33/288, 33/203.18, 33/336, 33/337
• US Class Current: 356/139.09
• CPC Class Codes: G01B 11/2755 using photoelectric detection means
• CPC Class Codes: G01B 2210/283 Beam projectors and related sensors

Abstract

Vehicle wheel alignment apparatus having active alignment determining means operatively mounted on the steerable and non-steerable wheels so as to be substantially insensitive to mechanical distortion of the vehicle wheels and operable in combination with wheel run out compensation means to produce wheel alignment results of improved accuracy, and utilizing the improved arrangement of alignment apparatus for supplying information which can be used for computing the important angular relationship of the wheels to a vehicle reference.

Claims

1. In apparatus for determining the alignment positions of vehicle wheels in relation to a reference axis of the vehicle and to the thrust line of the non-steerable wheels, the improvement which comprises:

(a) first alignment determining instruments carried by each of a set of steerable wheels so as to be in a substantially vertical plane containing the axis of rotation of said steerable wheels;

(b) second alignment determining instruments carried by each of a set of non-steerable wheels so as to be in a substantially vertical plane containing the axis of rotation of said non-steerable wheels;

(c) third alignment determining instruments supported from said steerable wheels in position to be in line-of-sight with each other transversely of the vehicle;

(d) radiant energy beam projectors and beam sensors in each of said first, second and third alignment determining instruments in positions such that the radiant energy beams from first instruments are in the line-of-sight to be sensed by said beam sensors in second instruments, radiant energy beams from second instruments are in the line-of-sight to be sensed by said beam sensors in first instruments, said first and second instruments are arranged in cooperating pairs along opposite longitudinal sides of the vehicle so as to be spaced in the longitudinal direction between said steerable and non-steerable wheels; and

(e) radiant energy beam projectors and beam sensors in said third alignment determining instruments in positions of cooperation transversely of the vehicle adjacent the steerable wheels, whereby said first and third instruments cooperate to generate signals determinative of the alignment positions of the steerable wheels relative to the vehicle reference axis and said second instruments cooperate with said first instruments to generate signals determinative of the thrust line effect of the non-steerable wheel on said steerable wheels.

2. Apparatus for determining the angular relationship of the steerable and non-steerable wheels of a vehicle relative to a longitudinal reference axis of the vehicle and the thrust line of the non-steerable wheels, the apparatus being associated with the wheels in sets longitudinally spaced a distance representing the vehicle wheel base and the wheel tread width, said apparatus comprising:

(1) first and second wheel position determining instruments carried by each wheel of the steerable wheel set;

(a) a first one of said instruments being in line-of-sight with each other transversely of the vehicle;

(2) a single angle determining instrument carried by each non-steerable wheel in position to be in line-of-sight with a second instrument carried by a steerable wheel at the same longitudinal side of the vehicle,

(a) said single instruments and said second instruments being located in substantial alignment with the axis of rotation of the vehicle wheels on which each is carried, such that each instrument represents the plane of wheel rotation;

(3) and all of said instruments being cooperatively operable for generating signals representative of the positions of the individual wheels in said sets for determining the thrust line positions of the non-steerable wheels relative to the longitudinal reference axis of the vehicle, and for determining the effect on the positions of the steerable wheels of the thrust line alignment of the non-steerable wheels.

3. Apparatus for determining the angular alignment relationship of the steerable and non-steerable wheels of a vehicle relative to a longitudinal reference axis of the vehicle to the thrust line of the non-steerable wheels, the apparatus being associated with the arrangement of the longitudinally and transversely spaced wheels representing the vehicle wheel base and tread width dimensions, said apparatus comprising:

(1) a pair of alignment determining instruments mounted on each of the steerable wheels,

(a) with a first one of said instruments on each steerable wheel being positioned to align substantially with the axis of wheel rotation so as to have a minimum of lateral displacement to the vehicle longitudinal reference axis upon turning of the steerable wheels,

(b) and a second one of said instruments on each steerable wheel being positioned forwardly of the wheels so that said second instruments are in position for obtaining cooperation therebetween transversely of the vehicle wheels;

(2) a single measuring instrument on each of the non-steerable wheels in position to align substantially with the axis of wheel rotation, such that each instrument represents the plane of wheel rotation,

(3) said first ones of said instruments being positioned to be in alignment determining cooperative relationship with said single instruments positioned at the same side of the vehicle wheel base, and said second ones of the instruments being in alignment determining cooperative relationship with each other across the tread width of the vehicle,

(a) said instruments generating signals representive of the position of the respective wheels relative to the vehicle reference axis and the thrust line of the non-steerable wheels;

(4) and alignment computer means operatively connected with each of said instruments and including means to display the values of the computed angles from the signals generated by said instruments,

(a) such that the toe alignment determination of the steerable wheels and the non-steerable wheels and the thrust line alignment determination of the non-steerable wheels is displayed in relation to the vehicle longitudinal reference axis.

4. Apparatus for determining the existing alignment of the steerable and non-steerable vehicle wheels relative to a longitudinal reference axis of the vehicle and to the thrust line of the non-steerable wheels, in which the apparatus comprises:

(1) six alignment determing instruments, each embodying a radiant energy projector and signal generating radiant energy sensor means mounted such that

(a) each non-steerable vehicle wheel supports one instrument in position to represent the plane of rotation of that wheel and in alignment with its axis of rotation,

(b) each steerable vehicle wheel supports a first instrument in position to represent the plane of rotation of that wheel and in alignment with its axis of rotation, and

(c) each steerable vehicle wheel also supports a second instrument in position to represent the angular position of the plane of rotation of that wheel relative to the longitudinal reference axis of the vehicle;

(2) said one instrument at each non-steerable wheel being in line-of-sight with said first instrument at each steerable wheel at the same longitudinal side of the vehicle for mutual cooperation therewith, such that

(a) the radiant energy sensors in said one instrument and said first instrument are energized by the radiant energy projected from the projectors in said first instrument and said one instrument respectively;

(3) said second instruments being in mutual cooperative line-of-sight positions such that

(a) the radiant energy sensor in each instrument is energized by the radiant energy projected from the projector in the cooperative instrument;

(4) said signals generated by said sensors representing the position of the respective vehicle wheels;

(5) and means operatively connected to each individual instrument for processing the signals generated by each of said radiant energy sensors such that

(a) the toe alignment of the steerable wheels and the toe alignment and thrust line of the non-steerable wheels is determined in relation to the longitudinal reference axis of the vehicle. .Iadd.

5. A wheel alignment measuring apparatus designed for measuring wheel alignment angles of the vehicle having front and rear wheels and comprising:

six angle measuring units,

first and second said angle measuring units adapted for connection respectively to the left and right front wheels of the vehicle and including angle pickup means for measuring and producing signals indicating the total tracking angles of both front wheels,

third and fifth said angle measuring units adapted for connection respectively to the left front wheel and a left rear wheel and including angle pickup means for measuring and producing signals indicating the angles of these wheels,

and fourth and sixth said angle measuring units adapted for connection respectively to the right front wheel and a right rear wheel and including angle pickup means for measuring and producing signals indicating the angles of these wheels,

means rigidly joining the first said angle measuring unit with said third angle measuring unit,

means rigidly joining said second angle measuring unit with said fourth angle measuring unit, and

an electrical circuit means for receiving signals from said angle pickup means and for producing a reading for wheel alignment data from the angles measured by said angle measuring units. .Iaddend. .Iadd.

6. The structure as claimed in claim 5 wherein said angle measuring units have relative placements and polarities arranged to cut out effects produced by track differences and wheel base differences so that output readings are produced free of such differences. .Iaddend.