Apparatus and method for automatically compensating for lateral runout

• US 20020088316A1
• Filed: 10/03/2001
• Published: 07/11/2002
• Est. Priority Date: 09/04/1996
• Status: Active Grant

• Current Assignee: Bonita IP LLC (Snap-On Incorporated)
• Original Assignee: Joseph B. Willey
• Inventors: Newell, Harold, Wiggins, John
• Granted Patent: US 6,895,841 B2
• Time in Patent Office: Days
• US Class Current: 82/1.11
• CPC Class Codes: B23B 2235/045 Simultaneous machining of both sides of the brake disc
• CPC Class Codes: B23B 2235/21 Compensation of run out
• CPC Class Codes: B23B 5/04 for reconditioning hubs or brake drums or axle spindles without removing same from the vehicle
• CPC Class Codes: Y10T 82/10 Process of turning
• CPC Class Codes: Y10T 82/21 Portable lathe for brake drum, disc, or shoe
• CPC Class Codes: Y10T 82/2502 with program control
• CPC Class Codes: Y10T 82/2535 Electrical type
• CPC Class Codes: Y10T 82/2571 Alignment adjuster
• CPC Class Codes: Y10T 82/2574 Stop [e.g., carriage, tool, work, etc.]

Abstract

An apparatus and method for automatically compensating for the lateral runout between an on-car lathe apparatus and a vehicle hub axis including one or more stop discs that rotate with the drive shaft of the lathe and that can be selectively stopped from rotating with the shaft by a stop mechanism. In response to such stopping, one or more adjustment discs are caused to rotate in order to adjust the relative position of the axis of the lathe with respect to the axis of the disc brake assembly. In this manner, the system compensates for and corrects lateral runout that exists between two concentrically attached rotating shafts.

Claims

1. An on-car disc brake lathe system for resurfacing brake disc of a vehicle brake assembly, said brake lathe comprising a lathe body with a driving motor, a cutting head operably attached to said body, and a drive shaft, said on-car brake lathe system further defined by an alignment system comprising:

an input adaptor configured to rotate with said drive shaft;

an output adaptor configured to rotate with said drive shaft;

at least one stop disc positioned between said input and output adaptor and operable to follow the rotation of said drive shaft and operable to rotate relative to the rotation of said drive shaft; and

at least one adjustment disc associated with a respective said at least one stop disc and operable to rotate in response to the relative rotation of said at least one stop disc, said at least one adjustment disc configured to be capable of adjusting the axial alignment of said drive shaft with respect to an axis of rotation of a brake disc.

2. An on-car disc brake lathe system as defined in claim 1 wherein:

at least one stop mechanism associated with said at least one said stop disc wherein said stop mechanism moves from a first stop position and a second withdrawn position such that when said stop mechanism is in said first stop position, said stop disc is caused to rotate relative to the rotation of said drive shaft;

3. An on-car disc brake lathe system as defined in claim 2 wherein:

said at least one stop disc comprises a pair of stop discs rotatably secured to said input adaptor such that said pair of stop disc rotate with said input adaptor when said associated stop mechanism is in said second withdrawn position and at least one of said pair of stop discs rotates relative to said input adapter when said associated stop mechanism is in its first stop position.

4. An on-car disc brake lathe system as defined in claim 3 wherein:

said at least one stop disc comprises a further pair of stop discs rotatably secured to said output adaptor such that said further pair of stop disc rotate with said output adaptor when said associated stop mechanism is in said second withdrawn position and at least one of said further pair of stop discs rotates relative to said input adapter when said associated stop mechanism is in its first stop position.

5. An on-car disc brake lathe system as defined in claim 4 wherein:

said at least one adjustment disc comprises a first adjustment disc operably associated with said pair of stop discs and a second adjustment disc operably associated with said further pair of stop disc.

6. An on-car disc brake lathe system as defined in claim 5 wherein:

said first and second adjustment disc comprise slant discs having a slanted surface such that said slanted surfaces of said slant discs are opposed to each other in an abutting relationship.

7. An on-car disc brake lathe system as defined in claim 5 further comprising:

a first gear train operably associated with said pair of stop discs and a second gear train operably associated with said further pair of stop discs, said gear trains configured to follow the movement of said respective pair of stop discs, said first gear train being operably associated with said first adjustment disc and said second gear train being operably associated with said second adjustment disc.

8. An on-car disc brake lathe system as defined in claim 7 wherein said first and second gear trains are configured such that when the associated stop mechanism stops one of said respective pair of stop discs, the respective adjustment disc is caused to rotate in a first rotational direction and when the stop mechanism stops the other of said respective pair of stop discs, the respective adjustment disc is caused to rotate in a rotational direction opposite to the first rotational direction.

9. An on-car disc brake lathe system as defined in claim 8 further comprising:

a ring gear operably connected to the first slant disc such that movement of said ring gear is followed by said slant disc.

10. An on-car disc brake lathe system as defined in claim 5 wherein said gear train comprises a first gear section associated with one of said pair of stop discs and a second gear section associated with the other of said stop discs wherein:

said first gear section comprises a first gear element operable to rotate with a respective stop disc, a second gear element meshed with said first gear element, and a third gear element operable to rotate with said second gear element, said third gear element being meshed with said ring gear such that rotation of the associated stop disc causes respective rotation of the first, second, and third gear elements thereby causing rotation of the ring gear in said first rotational directional.

said second gear section comprises a first gear element operable to rotate with a respective stop disc, a second gear element meshed with said first gear element, and a third gear element meshed with said second gear element, and fourth gear element operable to rotate with said third gear element, said fourth gear element being meshed with said ring gear such that rotation of the associated stop disc causes respective rotation of the first, second, third, and fourth gear elements thereby causing rotation of the ring gear in a rotational direction opposite said first rotational directional.

11. An on-car disc brake lathe system as defined in claim 10 further comprising a drive arm keyed to rotate with said drive shaft, said drive arm rotationally coupled to the output adaptor such that said output adaptor follows the rotation of said drive arm, said output adapter further configured to be capable of rotating about a vertical axis perpendicular to the central axis of said drive shaft.

12. An on-car disc brake lathe system as defined in claim 2 wherein said at least one stop disc comprises starwheels having a plurality of protruding teeth.

13. An on-car disc brake lathe system as defined in claim 12 wherein said stop mechanism comprises an electromagnetic element and a toothed catch member operable to engage at least one of said plurality of teeth of said star wheels.

14. An on-car disc brake lathe system as defined in claim 13 further comprising means for timing the actuation of the stop mechanism such that the toothed catch moves into its first stop position to contact a specified at least one stop disc upon receipt of a control signal.

15. An on-car disc brake lathe system as defined in claim 1 further comprising:

a draw bar extending through the body of said lathe and said alignment system and operable for connection to a hub adapter of a vehicle brake assembly.

16. An on-car disc brake lathe system as defined in claim 1 further comprising means for measuring the lateral runout of a brake disc, said means for measuring producing an electrical control signal that actuates said stop mechanism.

18. An on-car disc brake lathe system as defined in claim 17 wherein:

said at least one disc comprises a pair of discs rotatably secured to said input adaptor such that said pair of disc rotate with said input adaptor and can be caused to rotate relative to said input adapter.

19. An on-car disc brake lathe system as defined in claim 18 wherein:

said at least one disc comprises a further pair of discs rotatably secured to said output adaptor such that said further pair of disc rotate with said output adaptor and can be caused to rotate relative to said output adapter.

20. An on-car disc brake lathe system as defined in claim 19 wherein:

said at least one adjustment disc comprises a first adjustment disc operably associated with said pair of discs and a second adjustment disc operably associated with said further pair of stop disc,

said first and second adjustment disc comprise slant discs having a slanted surface such that said slanted surfaces of said slant discs are opposed to each other in an abutting relationship.

21. An on-car disc brake lathe system as defined in claim 20 further comprising:

a first gear train operably associated with said pair of stop discs and a second gear train operably associated with said further pair of stop discs, said gear trains configured to follow the movement of said respective pair of stop discs, said first gear train being operably associated with said first adjustment disc and said second gear train being operably associated with said second adjustment disc.

22. An on-car disc brake lathe system as defined in claim 21 further comprising:

a first adapter cover adjacent to said input adapter and a second adapter cover adjacent said output adapter, said input and output adapters, adapter covers, and adjustment discs having a concentric axis of rotation.

23. An on-car disc brake lathe system as defined in claim 22 further comprising:

thrust bearings positioned between surfaces of said adapter and adjacent surfaces of said adjustment discs.

27. A method for adjusting the alignment as set forth in claim 25 further including the steps of:

(e) rotating simultaneously the same stop discs of said input and output adaptor a predetermined degree and repeating measuring step (a) and comparing step (b), and if the runout is determined to be lower in the repetition, continue to rotate and repeat step (a) and (b) until the runout is determined to be increase; and

(f) rotating simultaneously the other and the same stop discs of said input and output adaptor a predetermined degree and repeating measuring step (a) and comparing step (b), and if the runout is determined to be lower in the repetition, continue to rotate and repeat step (a) and (b) until the runout is determined to be increase.

28. A method for adjusting the alignment as set forth in claim 26 further including the step of:

maintaining a count of the number of rotations of the stop discs and when the count reaches a predetermined number, adjust the stored acceptable runout limit to a value that is higher but still within an acceptable level.

29. A method for adjusting the alignment as set forth in claim 26 further including the step of:

adjust the degree of rotation of each of the stop disc depending on the measured level of runout.

17. An alignment assembly for use in an on-car disc brake lathe system for resurfacing brake disc of a vehicle brake assembly, said alignment system comprising:

an input adaptor configured to rotate with a drive shaft of a brake lathe system;

an output adaptor configured to rotate with a drive shaft of a brake lathe system;

at least one disc positioned between said input and output adaptor and operable to follow the rotation of said drive shaft and operable to rotate relative to the rotation of said drive shaft; and

at least one adjustment disc associated with a respective said at least one disc and operable to rotate in response to the relative rotation of said at least one disc, said at least one adjustment disc configured to be capable of adjusting the relative axial alignment of said input adaptor with said output adaptor.

24. An apparatus for aligning the axes of two rotating shafts comprising:

a first input adaptor configured to rotate with one of said shafts;

a second output adaptor configured to rotate with the other of said shafts;

at least one stop disc positioned between said input and output adaptor and operable to follow the rotation of the first shaft and operable to rotate relative to the rotation of said first shaft; and

at least one adjustment disc associated with a respective said at least one stop disc and operable to rotate in response to the relative rotation of said at least one stop disc, said at least one adjustment disc configured to be capable of adjusting the axial alignment of said first shaft with respect to an axis of rotation of said second shaft.

25. A method for adjusting the alignment between a vehicle brake assembly and an on-car disc brake lathe having a driving motor, a cutting head operably attached to said body, and a drive shaft wherein said on-car disc brake lathe is operably attached to the hub of a vehicle brake assembly in order to compensate for runout comprising the steps of:

(a) measuring the rotational acceleration of the lathe that reflects to lateral runout of the attachment between the vehicle brake assembly and the on-car disc brake lathe;

(b) comparing the measured runout value of the lathe with a stored acceptable runout limit and cease further adjustment if the measured value is below an acceptable limit;

(c) adjusting in a first direction the relative axial position of the lathe drive shaft with respect to the axis of rotation of the vehicle brake assembly;

(d) repeating measuring step (a), and if the runout is determined to be lower in the repetition, repeat step (c) until the runout is determined to be increase;

(e) adjusting in a second direction the relative axial position of the lathe drive shaft with respect to the axis of rotation of the vehicle brake assembly;

(f) repeating measuring step (a), and if the runout is determined to be lower in the repetition, repeat step (c).

26. A method for adjusting the alignment in order to compensate for runout between a vehicle brake assembly and an on-car disc brake lathe having a driving motor, a cutting head operably attached to said body, and a drive shaft wherein said on-car disc brake lathe is operably attached to the hub of a vehicle brake assembly, said brake lathe further including a alignment system having an input adaptor and an output adaptor configured to rotate with said drive shaft, and a first pair and second pair of stop discs rotatably engaged to respective said input and output adapters, said first pair of stop disc being operably engaged with a first adjustment disc and said second pair of stop disc being operably engaged with a second adjustment disc such that rotation of one of said pair of stop disc causes a respective adjustment disc to rotate in a first direction and rotation of the other of said pair of stop disc causes a respective adjustment disc to rotate in a second direction opposite to the first direction, said method comprising the steps of:

(a) measuring the rotational acceleration of the lathe that reflects to lateral runout of the attachment between the vehicle brake assembly and the on-car disc brake lathe;

(b) comparing the measured runout value of the lathe with a stored acceptable runout limit and cease further adjustment if the measured value is below an acceptable limit;

(c) rotating one of the pair of the stop disc of said output adaptor a predetermined degree and repeating measuring step (a) and comparing step (b), and if the runout is determined to be lower in the repetition, continue to rotate and repeat step (a) and (b) until the runout is determined to be increase; and

(d) rotating the other of the pair of the stop disc of said output adaptor a predetermined degree and repeating measuring step (a) and comparing step (b), and if the runout is determined to be lower in the repetition, continue to rotate and repeat step (a) and (b) until the runout is determined to be increase.