Wheel balancer

• US 6,244,108 B1
• Filed: 05/06/1999
• Issued: 06/12/2001
• Est. Priority Date: 09/06/1996
• Status: Expired due to Term

• Current Assignee: Snap-on Equipment Europe Ltd. (Snap-On Incorporated)
• Original Assignee: Snap-on Equipment Europe Ltd. (Snap-On Incorporated)
• Inventors: Meaney, Paul P, McInnes, Duncan W, Cullen, Richard J, Fogarty, Padraig
• Primary Examiner(s): CHAPMAN JR, JOHN E
• Application Number:
  US09/254,471
• Time in Patent Office: 768 Days
• Field of Search: 734/62, 734/60, 734/66, 734/67, 356/139.09, 301/5.21
• US Class Current: 73/462
• CPC Class Codes: G01M 1/02 Details of balancing machines or devices
• CPC Class Codes: G01M 1/08 Instruments for indicating directly the magnitude and phase of the imbalance

Abstract

A wheel balancer (1) for balancing an alloy wheel (2) comprises a support housing (30) and a main shaft (36) onto which the wheel (2) is mounted. A sub-housing (35) rotatably carries the main shaft (36), imbalance forces in the main shaft (36) and their respective directions are monitored for determining the magnitude and angular positions of balance weights required for correcting imbalances in the wheel (2) in selected balancing planes (17) and (18). A telescoping extendible sensor arm (54) is pivotally mounted about a vertical pivot axis on the support housing (30) for detecting balance weight receiving locations on the inner surface (10) of a wheel hub (4) of the wheel (2) at the selected desired balancing planes (17) and (18). Balance weight positions (22) at which correcting balance weights (20) are to be attached to the inner surface (10) of the wheel hub (4) in the respective balancing planes (17) and (18) are indicated by a laser light source (70) which directs a pencil laser beam (72) at the inner surface (10) in the lower front quadrant (23) of the wheel hub (4) when the balance weight position (22) is aligned with the laser light source (70). A laser light dot formed on the inner surface (10) indicates the angular center line (21) of the balance weight position (22) and an inner side edge (25) of the balance weight position thereby indicating to the operator the precise position at which the correcting balance weight (20) is to be attached to the wheel hub.

Claims

1. A wheel balancer (1) for measuring imbalance in a vehicle wheel (2) in a balancing plane (17,18) normal to the axis (38) of rotation of the vehicle wheel (2), and for indicating the position (22) on the wheel (2) at which a balance weight (20) is to be located for correcting the imbalance, the wheel balancer (1) comprising a support means (30), a main shaft (36) rotatable about a rotational axis (38) in the support means (30), a receiving means (39) located on the main shaft (36) for receiving the vehicle wheel (2) with the axis of rotation of the vehicle wheel (2) co-axial with the rotational axis (38) of the main shaft (36), a sensing means (53,91) for detecting the balancing plane (17,18) of the vehicle wheel (2) and a balance weight receiving location (10) adjacent the balancing plane (17,18), and for generating signals representative of the position of the balancing plane (17,18) along the rotational axis (38) relative to a reference plane and the radius of the balance weight receiving location (10) adjacent the balancing plane (17,18), a monitoring means (41,44) for monitoring rotation of the main shaft (36) and for generating signals representative of the magnitude and angular direction of imbalance forces in the main shaft (36), a computing means (45,46) for computing the magnitude of a correcting balance weight (20) and the angular position of the balance weight (20) to be located at the balance weight receiving location (10) in the balancing plane (17,18) for correcting the imbalance in response to signals generated by the sensing means (53,91) and the monitoring means (41,44), and a position indicating means (70,72) responsive to the computing means (45,46) for indicating the angular position relative to the wheel axis at which the correcting balance weight (20) is to be located, characterized in that the position indicating means (70,72) indicates a balance weight position (22) in the balance weight receiving location (10) adjacent the balancing plane (17,18) at which the correcting balance weight (20) is to be located, the angular position of the balance weight position (22) and its position relative to the reference plane being indicated by the position indicating means (70,72), and the position indicating means (70,72) indicates the balance weight position (22) by means of a visually perceptible indication (86) on the wheel (2).

2. A wheel balancer as claimed in claim 1 characterized in that the indicating means (70,72) is adapted for indicating the balance weight position (22) when the wheel (2) is in a rotational position such that the balance weight position (22) is located in a position which is accessible to the operator.

3. A wheel balancer as claimed in claim 1 characterized in that the rotational axis (38) defined by the main shaft (36) extends horizontally, and the position indicating means (70,72) is adapted for indicating the balance weight position (22) when the balance weight position (22) is located in a lower half of the wheel (22) relative to the main shaft (36).

4. A wheel balancer as claimed in claim 3 characterized in that the support means (30) defines a front face (31), a rear face (32) and a side face (34) of the wheel balancer (1), the side face (34) extending between the front face (31) and the rear face (32) thereof, and the main shaft (36) extending outwardly from the side face (34) of the support means between the front and rear faces (31,32), so that in use an operator normally operates the wheel balancer (1) from a position in front of the front face (31) thereof, and the position indicating means (70,72) indicates the balance weight position (22) when the balance weight position (22) is located in a lower front quadrant (23) of the wheel (2) relative to the main shaft (36) and the support means (30).

5. A wheel balancer as claimed in claim 3 characterized in that the support means (30) and the main shaft (36) are located relative to each other for providing easy access by an operator to the balance weight position (22) when the balance weight position (22) is indicated by the position indicating means (70,72).

6. A wheel balancer as claimed in claim 3 characterized in that the position indicating means (70,72) is adapted for indicating the balance weight position (22) when the balance weight position (22) lies in a position at an angle in the range of ±

30°

to ±

80°

from bottom dead centre of the wheel (2).

7. A wheel balancer as claimed in claim 6 characterized in that the position indicating means (70,72) is adapted for indicating the balance weight position (22) when the balance weight position (22) lies in a position at an angle in the range of ±

57°

to ±

71°

from bottom dead centre of the wheel (2).

8. A wheel balancer as claimed in claim 1 characterized in that the position indicating means (70,72) is a non-contact indicating means (70,72) indicates the center line (21) of the balance weight position (22) parallel to the rotational axis (38) of the main shaft (36), and a circumferential side edge (25) of the balance weight position (22).

9. A wheel balancer as claimed in claim 8 characterized in that the position indicating means (70,72) indicates the circumferential side edge (25) of the balance weight position (22) which is adjacent the support means (30).

10. A wheel balancer as claimed in claim 1 characterized in that the position indicating means (22) indicates two balance weight positions (22) on the wheel (2) adjacent respective axially spaced apart balancing planes (17,18) for dynamic balancing of the wheel (2).

11. A wheel balancer as claimed in claim 1 characterized in that the position indicating means (70,72) is a non-contact indicating means (70,72).

12. A wheel balancer as claimed in claim 11 characterized in that the light source (70) projects a dot (86) of light onto the balance weight receiving location (10) for indicating each balance weight position (22), and the light source (70,72) is powered up to project the light beam (72) only when the wheel (2) has been rotated into a position with the respective balance weight positions (22) located in the position which is accessible to the operator, and the light source (70,72) only remains powered up to project the light beam (72) for so long as each balance weight position (22) remains located in the position which is accessible to the operator.

13. A wheel balancer as claimed in claim 11 characterized in that the position indicating means (70,72) is pivotally mounted for pivoting in a single plane for sweeping the light beam (72) through an arc in a horizontal plane below the main shaft (36) for indicating each balance weight position (22), and a drive means (40) is provided for pivoting the position indicating means (70,72) in the single plane about a vertically extending pivot axis in response to the computing means (45,46).

14. A wheel balancer as claimed in claim 13 characterized in that the position indicating means (70,72) is mounted towards the rear face (32) of the support means (30) between a vertical plane containing the rotational axis (38) of the main shaft (36) and the rear face (32) of the support means (30) and the position indicating means (70,72) directs the light beam (72) outwardly of the side face (34) of the support means (30) in a generally sideward forward direction relative to the support means (30).

15. A wheel balancer as claimed in claim 11 characterized in that the sensing means (91) is a non-contact sensing means (91) and co-operates with the position indicating means (70) for detecting each balancing plane (17,18) of the vehicle wheel (2) and the balance weight receiving location (10) adjacent each balancing plane (17,18), the position indicating means (70,72) being movable for directing the light beam (72) at the wheel (2) so that the beam (72) strikes the wheel (2) at the balance weight receiving location (10) adjacent each balancing plane (17,18), so that a dot of light from the light beam (72) projected onto each balance weight receiving location (10) is detectable by the sensing means (91), and a feedback means (80) is provided for feeding back to the computing means (45,46) signals representative of the position of the position indicating means (70) when the beam (72) strikes the wheel (2) at the balance weight receiving location (10) in each balancing plane (17,18), so that the combination of signals generated by the sensing means (91) and the feedback means (80) are representative of the position of each balancing plane (17,18) along the rotational axis (38) relative to the reference plane and the radius of the balance weight receiving location (10) adjacent each balancing plane (17,18).

16. A wheel balancer as claimed in claim 15 characterized in that the position indicating means (70,72) and the sensing means (91) are mounted at spaced apart locations on a mounting means (92), the mounting means (92) being movable for moving the position indicating means (70,72) for directing the beam (72) to the wheel (2) at the balance weight receiving location (10) in each balancing plane (17,18) for facilitating detecting of the balance weight receiving location (10) in each balancing plane (17,18) by the sensing means (91).

17. A wheel balancer as claimed in claim 16 characterized in that the sensing means (91) is a charge coupled integrated opto sensor (91), and is mounted on the mounting means (92) for scanning an arc on the wheel (2) adjacent the balance weight receiving location (10) adjacent each balancing plane (17,18), the position indicating means (70,72) being mounted on the mounting means (92) for directing the beam (72) to strike the wheel (2) within the arc scanned by the sensing means (91) for facilitating detection of the balance weight receiving location (10) in each balancing plane (17,18) by the sensing means (91).

18. A wheel balancer as claimed in claim 11 characterized in that the position indicating means (70,72) comprises a light source (70) which projects a pencil light beam (72) for indicating each balance weight position (22).

19. A wheel balancer as claimed in claim 1 characterized in that the sensing means (53) is a contact sensing means (54).

20. A wheel balancer as claimed in claim 19 characterized in that the sensing means (53) comprises an extendible sensor arm (54) which is connected to the support means (30) and is extendible for engaging the wheel (2) adjacent the balance weight receiving location (10) adjacent each balancing plane (17,18).

21. A wheel balancer as claimed in claim 1 characterized in that the position indicating means (70,72) indicates each balance weight position (22) on an inner surface (10) of a wheel hub (4) of the wheel (2) which defines a wheel well (15).

22. A wheel balancer as claimed in claim 21 characterized in that the wheel balancer (1) is adapted for balancing an alloy wheel (2) in which the wheel hub (4) is an alloy wheel hub (4).

23. A wheel balancer as claimed in claim 21 characterized in that the position indicating means (70,72) indicates each balance weight position (22) in the wheel well (15) at a location which lies axially between an inner rim (7) of the wheel hub (4) and spokes (11) of the wheel hub (4).

24. A wheel balancer as claimed in claim 1 characterized in that the indicating means (70,72) is adapted for indicating the balance weight position (22) when the rotational position of the wheel (2) is such that the balance weight position (22) is located in a position which is visually accessible to the operator.

25. A method using a wheel balancer (1) for measuring imbalance in a vehicle wheel (2) in a balancing plane (17,18) normal to the axis of rotation of the vehicle wheel (2), the method comprising the steps of attaching the vehicle wheel (2) to a receiving means (39) which is located on a main shaft (36) of the wheel balancer (1), which in turn is rotatably supported in a support means (30), the axis of rotation of the vehicle wheel (2) coinciding with the rotational axis (38) of the main shaft (36), detecting by means of a sensing means (53,91) of the wheel balancer (1) the balancing plane (17,18) and a balance weight receiving location (10) adjacent the balancing plane (17,18) at which a correcting balance weight (20) is to be attached, and generating signals by the sensing means (53,91) which are representative of the position of the balancing plane (17,18) along the rotational axis (38) of the main shaft (36) relative to a reference plane and the radius of the balance weight receiving location (10), monitoring rotation of the main shaft (36) by a monitoring means (41,44), and generating signals by the monitoring means (41,44) which are representative of the magnitude and angular direction of the imbalance forces in the main shaft (36), computing by means of a computing means (45,46) from signals received from the sensing means (53,91) and the monitoring means (41,44) the magnitude of a correcting balance weight (20) and the angular position at which the balance weight (20) is to be located at the balance weight receiving location (10) adjacent the balancing plane (17,18) for correcting the imbalance, and indicating by means of a position indicating means (70,72) in response to signals received from the computing means (45,46) the angular position at which the correcting balance weight (20) is to be located, characterized in that a balance weight position (22) in the balance weight receiving location (10) adjacent the balancing plane (17,18) is indicated by the position indicating means (70,72), the angular position of the balance weight position (22) and its position relative to the reference plane being indicated by the position indicating means (70,72), and the balance weight position (22) is indicated by the position indicating means (70,72) by means of a visually perceptible indication (86) on the wheel (2).

26. A method as claimed in claim 25 characterized in that the method comprises the step of indicating the balance weight position (22) by the position indicating means (70,72) when the wheel (2) is in a rotational position such that the balance weight position (22) is located in a visually accessible position to the operator of the wheel balancer (1).

27. A method as claimed in claim 26 characterized in that the method comprises the step of indicating the balance weight position (22) by the position indicating means (70,72) when the balance weight position (22) is located facing upwardly rearwardly relative to the support means (30) of the wheel balancer (1).