RETENTION SYSTEM FOR ATTACHING TOOL BITS TO A BLADE ASSEMBLY

• US 20190316328A1
• Filed: 04/13/2018
• Published: 10/17/2019
• Est. Priority Date: 04/13/2018
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Parzynski, JR., David Bruno, Congdon, Thomas Marshall
• Granted Patent: US 11,732,445 B2
• Time in Patent Office: Days
• CPC Class Codes: E02F 3/815 Blades; Levelling or scarifying tools E02F3/40 takes precedence
• CPC Class Codes: E02F 3/8152 Attachments therefor, e.g. wear resisting parts, cutting edges E02F3/8155, E02F3/8157 take precedence; teeth per se E02F9/28
• CPC Class Codes: E02F 9/2808 Teeth
• CPC Class Codes: E02F 9/2816 Mountings therefor
• CPC Class Codes: E02F 9/2825 using adapters
• CPC Class Codes: E02F 9/2833 Retaining means, e.g. pins
• CPC Class Codes: E02F 9/285 characterised by the material used
• CPC Class Codes: E02F 9/2858 characterised by shape
• CPC Class Codes: E02F 9/2883 Wear elements for buckets or implements in general
• CPC Class Codes: E21C 35/18 Mining picks; Holders therefor planing knives E21C27/44
• CPC Class Codes: E21C 35/1837 characterised by the shape

Abstract

An orientation plate comprises a rectangular body defining a top surface, a bottom surface, a front surface, a back surface, a first end surface, a second end surface, and a thickness that is the minimum dimension of the body, and a plurality of apertures extending through the thickness of the body, each aperture defining a perimeter having at least one orientation flat.

Claims

1. A tool bit for use with a blade assembly of a grading machine, the tool bit comprising:

a shank portion defining a longitudinal axis, a free end and a perimeter, at least one anti-rotation feature on the perimeter extending to the free end and a cross-hole defining a cross-hole axis along which the cross-hole extends through the shank portion; and

a working portion extending downwardly axially from the shank portion;

wherein the working portion includes a rear region, a front working region defining a width with a midpoint, a first side region and a second side region, and the first side region and the second side region define an angle of extension measured in a plane perpendicular to the longitudinal axis, and the cross-hole axis passes through the width of the front working region when projected onto a plane perpendicular to the longitudinal axis.

2. The tool bit of claim 1 wherein the angle of extension forms a wider front working region than the rear region in a plane perpendicular to the longitudinal axis and the shank portion includes a cylindrical configuration defining a circumferential direction and a radial direction and the rear region at least partially forms a right angle with the radial direction in a plane perpendicular to the longitudinal axis, the cross-hole having a cylindrical configuration defining a cylindrical axis passing perpendicularly through the longitudinal axis of the shank portion, and the cross-hole axis passes through the midpoint of the width of the front working region when projected onto a plane perpendicular to the longitudinal axis.

3. The tool bit of claim 1, wherein the front working region includes a first angled surface and a second angled surface forming a first included angle with the first angled surface projected along the longitudinal axis onto a plane perpendicular to the longitudinal axis ranging from 130 degrees to 180 degrees or an arcuate surface defining a radius of curvature in a plane perpendicular to the longitudinal axis ranging from 50 mm to 65 mm.

4. The tool bit of claim 3 wherein the front working region includes a third angled surface forming a first external angle with the second angled surface projected along the longitudinal axis onto a plane perpendicular to the longitudinal axis ranging from 150 to 180 degrees.

5. The tool bit of claim 4 wherein the front working region further comprises a fourth angled surface forming a second included angle with the third angled surface projected along the longitudinal axis onto a plane perpendicular to the longitudinal axis ranging from 150 to 180 degrees.

6. The tool bit of claim 1 wherein the first side region or second side region include a first drafted side surface configured to improve penetration of the tool bit in use.

7. The tool bit of claim 6 wherein the rear region forms a first draft angle with the longitudinal axis measured in a plane containing the radial direction and the longitudinal axis, ranging from 0 to 40 degrees, the first side region forming a second draft angle with the longitudinal axis measured in a plane containing the radial direction and the longitudinal axis, ranging from 0 to 40 degrees, the second side region forming a third draft angle with the longitudinal axis measured in a plane containing the radial direction and the longitudinal axis, ranging from 0 to 40 degrees, and the front working region forms a fourth draft angle with the longitudinal axis measured in a plane containing the radial direction and the longitudinal axis, ranging from 0 to 30 degrees.

8. The tool bit of claim 1 wherein the angle of extension ranges from 0 to 50 degrees.

9. A blade assembly for use with a grading machine, the blade assembly comprising:

an adapter board defining an upper adapter board attachment portion, terminating in an upper adapter board free end, and a lower tool bit attachment portion, terminating in a lower adapter board free end, the lower tool bit attachment portion defining a width;

a plurality of tool bits configured to be attached to the adapter board, each tool bit including

a shank portion defining a longitudinal axis and a perimeter, a pair of parallel flat surfaces on the perimeter and a cross-hole defining a cross-hole axis extending through the flat surfaces perpendicularly; and

a working portion, wherein the working portion includes a rear region, a front working region defining a width with a midpoint, a first side region and a second side region, and the first side region and the second side region define an angle of extension measured in a plane perpendicular to the longitudinal axis, and the cross-hole axis passes through the width of the front working region when projected onto a plane perpendicular to the longitudinal axis; and

an orientation plate defining a plurality of apertures, each aperture having an orientation flat configured to contact a flat surface of the shank portion of tool bit.

10. The blade assembly of claim 9 wherein the working portion includes at least a first arcuate surface disposed longitudinally adjacent the shank portion, the at least first arcuate surface defining a radius of curvature that is equal to or greater than the half of the width of the lower tool bit attachment portion of the adapter board and the lower tool bit attachment portion of the adapter board defines a plurality of cylindrical thru-bores and the shank portion of the tool bit includes a cylindrical configuration defining a circumferential direction and a radial direction, the shank portion being configured to fit within one of the plurality of cylindrical thru-bores and he cross-hole having a cylindrical configuration defining a cylindrical axis passing perpendicularly through the longitudinal axis of the shank portion, and the cross-hole axis passes through the midpoint of the width of the front working region when projected onto a plane perpendicular to the longitudinal axis.

11. The blade assembly of claim 10 wherein the working portion includes a second arcuate surface disposed adjacent the first arcuate surface circumferentially on one side of the first arcuate surface and a third arcuate surface disposed adjacent the first arcuate surface on the other side of the first arcuate surface.

12. The blade assembly of claim 9 wherein the front working region includes a first angled surface and a second angled surface forming a first included angle with the first angled surface projected along the longitudinal axis onto a plane perpendicular to the longitudinal axis ranging from 130 to 180 degrees.

13. The blade assembly of claim 11 wherein the first arcuate surface, the second arcuate surface or the third arcuate surface define a radius of curvature ranging from 50 to 65 mm.

14. The blade assembly of claim 13 wherein the tool bit further comprises a rear region, a first side region extending from the second arcuate surface to the rear region, and a second side region extending from the third arcuate surface to the rear region.

15. The blade assembly of claim 14 further comprising a fourth arcuate surface extending circumferentially from the third arcuate surface.

16. The blade assembly of claim 14 wherein the rear region defines a first draft angle with the longitudinal axis ranging from 0 to 40 degrees, the first side region defines a second draft angle with the longitudinal axis ranging from 0 to 40 degrees, the second side region defines a third draft angle with the longitudinal axis ranging from 0 to 40 degrees, and the first arcuate surface, second arcuate surface and third arcuate surface define a fourth draft angle with the longitudinal axis ranging from 0 to 30 degrees.

17. An orientation plate configured to orient a tool bit relative to the centerline of an adapter board, the orientation plate comprising:

a rectangular body defining a top surface, a bottom surface, a front surface, a back surface, a first end surface, a second end surface, and a thickness that is the minimum dimension of the body; and

a plurality of apertures extending through the thickness of the body, each aperture defining a perimeter having at least one orientation flat.

18. The orientation plate of claim 17 wherein the plurality of apertures have two orientation flats parallel to each other and two circular portions connecting the two orientation flats.

19. The orientation plate of claim 18 wherein each of the plurality of apertures are identical.

20. The orientation plate of claim 18 wherein the thickness of the plate defines a midplane and the plate is symmetrical about the midplane.