Cutter disc with set back teeth for tunnel boring machine
AssigneeThe Robbins Company
InventorCarl E. Lenaburg
Life of this patent
Estimating the term…
Abstract
A cutter disc for a tunnel boring machine includes a middle disc portion defining a radially outer surface or edge for engaging a surface, a left toothed portion defining a first set of teeth set back from the outer edge, and a right toothed portion defining a second set of teeth set back from the outer edge. In an embodiment, a central bore through the cutter disc is configured to attach the cutter disc to a hub for rotatably mounting the cutter disc on a shaft. In an embodiment, the hub is formed integrally with the cutter disc. The left and right toothed portions provide structural support to the middle portion and facilitate rotation of the cutter disc when boring in soft or mixed conditions, but do not interfere with boring in hard rock conditions.
Claims20
A cutter disc for a cutter ring assembly for a tunnel boring machine comprises:
- a tool steel forging having three integral portions comprising:
- a middle disc portion having a first sidewall, a second sidewall, and a radially outer continuous cutter edge portion joining the first sidewall and the second sidewall;
- a first annular toothed portion extending from the first sidewall and defining a first plurality of teeth that are set back from the continuous cutter edge portion of the middle disc portion, wherein the first plurality of teeth define distal edges that slope away from the first sidewall and radially inwardly;
- and
- a second annular toothed portion extending from the second sidewall and defining a second plurality of teeth that are set back from the continuous cutter edge portion of the middle disc portion, wherein the second plurality of teeth define distal edges that slope away from the second sidewall and radially inwardly.
A cutter ring assembly for a tunnel boring machine comprising:
- a hub;
- a cutter disc mounted on the hub, the cutter disc comprising a tool steel forging having three integral portions comprising:
- (i) a middle disc portion having a first sidewall, a second sidewall, and a radially outer continuous cutter edge portion joining the first sidewall and the second sidewall, (ii) a first annular toothed portion extending from the first sidewall and defining a first plurality of teeth that are set back from the continuous cutter edge portion of the middle disc portion, wherein the first plurality of teeth define distal edges that slope away from the first sidewall and radially inwardly, and (iii) a second annular toothed portion extending from the second sidewall and defining a second plurality of teeth that are set back from the continuous cutter edge portion of the middle disc portion, wherein the second plurality of teeth define distal edges that slope away from the second sidewall and radially inwardly;
- a bearing assembly mounted in the hub and comprising an inner bearing race, an outer bearing race, and a plurality of roller bearings rotatably retained by the inner and outer bearing races;
- a shaft fixed to the inner bearing race;
- a first retainer and a second retainer, each retainer fixed to the shaft, wherein the first and second retainers are disposed on opposite ends of the hub and enclose the bearing assembly there between;
- and
- a first rotary seal group configured to sealingly engage the hub and the first retainer, and a second rotary seal group configured to sealingly engage the hub and the second retainer, whereby the hub and cutter disc are rotatably supported on the shaft.
Dependencies are inferred from the claim text.