Lobed Bushing For Track Assembly And Track-Type Machine Using Same

• US 20100139993A1
• Filed: 12/03/2009
• Published: 06/10/2010
• Est. Priority Date: 12/05/2008
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Sebright, Jason L., Abello, Benoit, Williamson, Steven, Diekevers, Mark S.
• Granted Patent: US 8,287,056 B2
• Time in Patent Office: Days
• US Class Current: 180/6.700
• CPC Class Codes: B62D 55/21 Links connected by transverse pivot pins
• CPC Class Codes: B62D 55/26 Ground engaging parts or elements tracks specially adapted for amphibious vehicles B60F3/0015
• CPC Class Codes: B62D 55/32 Assembly, disassembly, repair or servicing of endless-track systems
• CPC Class Codes: F16C 11/02 Trunnions; Crank-pins fastening crank-pins to webs, crank-pins integral with cranks F16C3/06, F16C3/22
• CPC Class Codes: F16C 25/04 self-adjusting

Abstract

A lobed bushing is provided for a track assembly of a track-type machine. The track assembly includes a first chain and a second chain coupled together with a track pin. A bushing, defining a longitudinal axis, includes a central bore oriented along the longitudinal axis and extending from a first end of the bushing to a second end of the bushing for receiving the track pin. The bushing includes a first lobe positioned at a first location about the longitudinal axis and a second lobe positioned at a second location about the longitudinal axis that is less than about 180° from the first location. The first end of the bushing has a substantially cylindrical shape.

Claims

1. A lobed bushing for a track assembly of a track-type machine, the track assembly including a first chain and a second chain coupled together with a track pin, comprising:

a bushing defining a longitudinal axis and having a central bore oriented along the longitudinal axis and extending from a first end of the bushing to a second end of the bushing for receiving the track pin, the bushing including a first lobe positioned at a first location about the longitudinal axis and a second lobe positioned at a second location about the longitudinal axis that is less than about 180°

from the first location, the first end having a substantially cylindrical shape.

2. The lobed bushing of claim 1, wherein the second end includes a substantially cylindrical shape.

3. The lobed bushing of claim 2, wherein the first end is press-fit within the first chain and the second end is press-fit within the second chain.

4. The lobed bushing of claim 1, further including a third lobe, wherein the first lobe, second lobe, and third lobe are symmetrical about the longitudinal axis.

5. The lobed bushing of claim 1, wherein the track assembly includes a drive sprocket having a forward rotational direction and a reverse rotational direction.

6. The lobed bushing of claim 5, wherein the first lobe defines a forward wear region of the bushing during rotation of the drive sprocket in the forward rotational direction, and the second lobe defines a reverse wear region of the bushing during rotation of the drive sprocket in the reverse rotational direction.

7. The lobed bushing of claim 6, wherein the bushing is oriented such that the first lobe engages a right flank of a drive sprocket tooth during rotation of the drive sprocket in the forward rotational direction, and the second lobe engages a left flank of the drive sprocket tooth during rotation of the drive sprocket in the reverse rotational direction.

8. A machine, comprising:

a frame;

a first track assembly coupled with the frame, the first track assembly including a first chain and a second chain coupled together with a track pin, a ground-engaging track shoe attached to the first chain and the second chain, and a bushing positioned about the track pin, the bushing including a first lobe and a second lobe; and

a drive sprocket configured to drive the first track assembly in a forward direction and a reverse direction, wherein the first lobe engages the drive sprocket when the first track assembly is driven in the forward direction and the second lobe engages the drive sprocket when the first track assembly is driven in the reverse direction.

9. The machine of claim 8, wherein the first lobe is positioned at a first location about a circumference of the bushing and the second lobe is positioned at a second location about the circumference that is less than about 180°

from the first location.

10. The machine of claim 9, further including a third lobe, wherein the first lobe, second lobe, and third lobe are equidistantly spaced about the circumference of the bushing.

11. The machine of claim 8, wherein the bushing is oriented such that the first lobe engages a right flank of a drive sprocket tooth when the first track assembly is driven in the forward direction, and the second lobe engages a left flank of the drive sprocket tooth when the first track assembly is driven in the reverse direction.

12. The machine of claim 8, wherein a first end of the bushing is press-fit within the first chain and a second end of the bushing is press-fit within the second chain.

13. The machine of claim 12, wherein the first end and the second end include substantially cylindrical cross-sections.

14. The machine of claim 8, further including a second track assembly, the first track assembly being positioned at a first side of the frame and the second track assembly being positioned at a second side of the frame.

15. A method of operating a track assembly of a track-type machine, comprising:

engaging a right flank of a drive sprocket tooth with a first lobe of a bushing during rotation of a drive sprocket in a forward rotational direction; and

engaging a left flank of the drive sprocket tooth with a second lobe of the bushing during rotation of the drive sprocket in a reverse rotational direction.

16. The method of claim 15, wherein the first engaging step includes driving the track assembly in a forward direction.

17. The method of claim 16, wherein the second engaging step includes driving the track assembly in a reverse direction.

18. The method of claim 17, wherein driving the track assembly in the forward direction or the reverse direction includes engaging ground-engaging track shoes with a surface.

19. The method of claim 15, wherein the first engaging step includes removing sacrificial wear material from the first lobe.

20. The method of claim 15, wherein the second engaging step includes removing sacrificial wear material from the second lobe.