Trencher Tooth (Patent No: 890315)

Inventor: White, Kenneth M.

Location: Calgary

Comments: N/A

Description: THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCIDSIVE PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A digger tooth mounting comprising a digger tooth having a longitudinal section defined by a substantially triangular frontal portion which blends into a rearwardly extending shank, supporting means having a pocket receiving said shank to support the tooth in operative position by inter-engagement of confronting surfaces of said pocket and said shank, one of said surfaces of said shank defining therein a shallow substantially circular recess, a coiled spring received in said recess acting between a bottom surface of said recess and said pocket to retain said tooth shank in the pocket, the axis of said coiled spring being substantially perpendicular to said one surface and to the corresponding confronting surface of the pocket.

2. A digger tooth mounting as claimed in claim 1, wherein said digger tooth has lateral extensions at a location between the frontal cutting portion and the shank; said lateral extensions being effective to protect the supporting means from abrasive wear due to cutting erosion when tooth and supporting means are in working operation.

3. A digger tooth mounting as claimed in claim 1 wherein the digger tooth shank comprises a pair of longitudinally extending prongs spaced apart along opposite side edges of the tooth shank and a longitudinally extending web interconnecting the prongs, the web being of lesser thickness than the prongs, and said recess being provided in a surface of the web.

4. A digger tooth mounting as claimed in claim 3 wherein a second recess is present in an opposite surface of the web and receives a second coiled spring in similar manner to said first mentioned coiled spring.

5. A digger tooth mounting as claimed in claim 3 wherein the upper and lower surfaces of each prong are connected to the respective upper and lower surface of the web by an oblique surface which makes an obtuse angle with contiguous upper or lower web and prong surfaces.

6. A digger tooth mounting as claimed in any one of claim 1, 3 or 5 wherein said confronting surfaces of the shank and pocket taper rearwardly to provide a wedging engagement of the tooth shank in the pocket.

7. A digger tooth mounting as claimed in any one of claims 1, 3 or 5 wherein said confronting surfaces of the shank and pocket taper rearwardly at an included angle of approximately 50 to provide a wedging engagement of the tooth shank in the pocket.

8. A digger tooth mounting as claimed in any one of claims 1, 3 or 5 wherein the coiled spring is a lock washer.

9. A digger tooth comprising a frontal cutting portion, which is substantially triangular in longitudinal section and rectangular in lateral section, and a shank which is joined to said cutting portion and extends rearwardly therefrom; said shank having a surface in which is defined a shallow substantially circular recess adapted to receive a coil spring such that the axis of said spring is substantially perpendicular to said surface, whereby in use when said shank is mounted in a pocket in a supporting means said spring acts to retain said shank in said pocket by engagement of its opposite ends with a bottom surface of the recess and a confronting pocket surface respectively.

10. A digger tooth as claimed in claim 9 further comprising lateral extensions between said frontal portion and said shank, in use said lateral extensions being effective to protect said supporting means from abrasive wear due to cutting erosion.

11. A digger tooth as claimed in claim 9 wherein the digger tooth shank comprises a pair of longitudinally extending prongs spaced apart along opposite side edges of the tooth shank and a longitudinally extending web interconnecting the prongs, the web being of lesser thickness than the prongs and said recess being provided in a surface of the web.

12. A digger tooth as claimed in claim 11 wherein a second such recess is present in an opposite surface of the web.

13. A digger tooth as claimed in claim 11 wherein the upper and lower surface of each prong are connected to the respective upper and lower surface of the web by an oblique surface which makes an obtuse angle of approximately 115° with contiguous upper or lower web and prong surfaces.

14. A digger tooth as claimed in any one of claims 9, 11 or 13 wherein said confronting shank surfaces taper rearwardly so that in use said shank has a wedging engagement in said pocket.

15. A digger tooth for mounting in a pocket in a supporting means, comprising a shank having surfaces for engagement with confronting surfaces of said pocket, a coiled spring, and a shallow substantially circular recess in one said shank surface for the reception of said coiled spring, such that said coiled spring is operative to retain said tooth in said pocket by engagement of the opposite ends of said coiled spring with a bottom surface of said recess and one confronting surface of said pocket, with the axis of said spring substantially perpendicular to said one shank surface and said one confronting surface.

16. The arrangement of claim 15 wherein said shank comprises a pair of longitudinally extending prongs spaced apart along opposite side edges of the tooth shank and a longitudinally extending web interconnecting the prongs, the web being of lesser thickness than the prongs, and said recess being provided in a surface of the web.

17. The arrangement of claim 15 or claim 16 wherein said shank surfaces taper rearwardly of the shank to provide in use a wedging engagement of said shank in the pocket.