Retainer for rotary cone drill bit
AssigneeCaterpillar Inc.
InventorsSwetha Suresh, Ebi Bernard, Tamilmurasu Annadurai, Chetan Dahiwal
Life of this patent
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Abstract
This disclosure describes, in part, systems and structures for a rotary cone drill bit having a body and rolling cone cutters, wherein the rolling cone cutters are coupled to the body through a bearing retention interface including ball bearings in a captured channel between the body and the rolling cone cutters. The ball bearings are inserted through an opening that is subsequently filled with a retainer pin having an engagement feature that ensures alignment of the retainer pin with respect to the captured channel and the ball bearings to reduce wear within the rotary cone drill bit.
Claims20
A rotary cone drill bit comprising:
- a bit body having an upper portion adapted for connection to a drill string for rotation of the rotary cone drill bit;
- one or more support arms attached to and extending from the bit body opposite the upper portion, the one or more support arms each comprising a journal having a bearing surface, the journal projecting generally downwardly and inwardly with respect to an associated support arm of the one or more support arms;
- one or more cutter cone assemblies equal to a number of support arms with each cutter cone assembly respectively rotatably mounted on one of the one or more support arms;
- an opening formed in an exterior surface of each support arm with a ball retainer passageway extending from the opening in the exterior surface of the support arm whereby ball bearings may be inserted through the opening and the ball retainer passageway to rotatably secure a respective cutter cone assembly on the journal, the opening comprising a first engaging feature;
- and
- a retainer pin configured to insert into the opening and the ball retainer passageway, the retainer pin comprising:
- a first end configured to interface with the bearing surface;
- a second end configured to engage with the opening, wherein the second end comprises a second engaging feature configured to engage with the first engaging feature of the opening to align the retainer pin within the ball retainer passageway.
A rotary drill bit comprising:
- a bit body configured to be rotated about a longitudinal axis and comprising at least one support arm;
- a journal extending from the at least one support arm and defining:
- a first channel around an exterior of the journal;
- and
- an opening through the journal to the first channel comprising a first engaging feature;
- a cone cutter rotatably mounted on the journal and defining a second channel around an interior of the cone cutter;
- a retention member disposed in the first channel and the second channel;
- and
- a retainer pin configured to insert into the opening, the retainer pin comprising:
- a first end configured to interface with the first channel and the retention member;
- a second end opposite the first end configured to engage with the opening;
- and
- a second engaging feature positioned at the second end and configured to engage with the first engaging feature of the opening and configured to align the retainer pin within the opening and relative to the first channel.
A retainer pin for ball bearings of a rotary drill bit comprising:
- a first end configured to interface with the ball bearings and comprising:
- a first side surface disposed on a first lateral side of the first end;
- a second side surface disposed on a second lateral side of the first end opposite the first lateral side;
- a bearing engagement surface disposed at a tip of the first end and having a profile corresponding to a shape of the ball bearings;
- a second end configured to engage with an opening of a body of the rotary drill bit;
- and
- an engaging feature configured to align the retainer pin within the opening of the body and relative to a bearing surface that supports the ball bearings.
Dependencies are inferred from the claim text.