Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
154 words
In an earth boring bit including a bit body with a bearing shaft connected to said bit body, a rotatable cutter mounted upon said bearing shaft, bearing means and seal means between said bearing shaft and said cutter, the improvement comprising: a lubricant circulation system including a lubricant reservoir in said bit body; first passage means for channeling lubricant from said lubricant reservoir to said bearing means; second passage means for channeling lubricant from said bearing means to said lubricant reservoir; and viscous pump means for pumping lubricant through said first and second passage means, said viscous pump means including an annular bearing element positioned between said bearing shaft and said rotatable cutter, said annular bearing element having an inner surface that rotates on said bearing shaft with a multiplicity of grooves in said inner surface of said annular bearing element, said grooves extending angularly along said inner surface of said annular bearing element.
Claim 2
Dependent Claim
154 words
In an earth boring bit including a bit body with a bearing shaft connected to said bit body, a rotatable cutter mounted upon said bearing shaft, bearing means and seal means between said bearing shaft and said cutter, the improvement comprising: a lubricant circulation system including a lubricant reservoir in said bit body; first passage means for channeling lubricant from said lubricant reservoir to said bearing means; second passage means for channeling lubricant from said bearing means to said lubricant reservoir; and viscous pump means for pumping lubricant through said first and second passage means, said viscous pump means including an annular bearing element positioned between said bearing shaft and said rotatable cutter, said annular bearing element having an inner surface that rotates on said bearing shaft with a multiplicity of grooves in said inner surface of said annular bearing element, said grooves extending angularly along said inner surface of said annular bearing element.
Claim 3
Dependent Claim
163 words
In an earth boring bit, said earth boring bit including a bit body having a bearing pin, a rotatable cutter, bearing means for promoting rotation of said cutter and a seal between said rotatable cutter and said bit body, a lubricant circulation system, comprising: a lubricant reservoir in said bit body; passage means for channeling lubricant from said lubricant reservoir to said bearing means and from said bearing means to said lubricant reservoir; and viscous pump means for circulating lubricant through said passage means, said viscous pump means including an annular bearing element positioned between said bearing pin and said rotatable cutter, said bearing element having an inner surface that rotates on said bearing pin with a series of grooves in said inner surface of said annular bearing element, said grooves extending angularly along said inner surface of said annular bearing element for providing a pumping force for circulating lubricant through said passage means as said rotatable cutter rotates on said bearing pin.
Claim 4
Dependent Claim
163 words
In an earth boring bit, said earth boring bit including a bit body having a bearing pin, a rotatable cutter, bearing means for promoting rotation of said cutter and a seal between said rotatable cutter and said bit body, a lubricant circulation system, comprising: a lubricant reservoir in said bit body; passage means for channeling lubricant from said lubricant reservoir to said bearing means and from said bearing means to said lubricant reservoir; and viscous pump means for circulating lubricant through said passage means, said viscous pump means including an annular bearing element positioned between said bearing pin and said rotatable cutter, said bearing element having an inner surface that rotates on said bearing pin with a series of grooves in said inner surface of said annular bearing element, said grooves extending angularly along said inner surface of said annular bearing element for providing a pumping force for circulating lubricant through said passage means as said rotatable cutter rotates on said bearing pin.
Claim 5
Dependent Claim
180 words
In an earth boring bit including a bit body with a bearing pin extending from said bit body, a rotatable cutter mounted to rotate about said bearing pin, bearing means and seal means between said bearing pin and said cutter, the improvement comprising: a lubricant circulation system including a lubricant reservoir in said bit body; first passage means for channeling lubricant from said lubricant reservoir to said bearing means; second passage means for channeling lubricant from said bearing means to said lubricant reservoir; and viscous pump means for circulating lubricant through said first and second passage means, said viscous pump means including an annular bearing element in said rotatable cutter positioned to contact and rotate about said bearing pin with said annular bearing element having an inner surface and a series of grooves in said inner surface of said annular bearing element that pump lubricant through said first and second passage means as said rotatable cutter rotates about said bearing pin, said series of grooves extending roughly at a 30° angle through said inner surface of said annular bearing element.
Claim 6
Dependent Claim
180 words
In an earth boring bit including a bit body with a bearing pin extending from said bit body, a rotatable cutter mounted to rotate about said bearing pin, bearing means and seal means between said bearing pin and said cutter, the improvement comprising: a lubricant circulation system including a lubricant reservoir in said bit body; first passage means for channeling lubricant from said lubricant reservoir to said bearing means; second passage means for channeling lubricant from said bearing means to said lubricant reservoir; and viscous pump means for circulating lubricant through said first and second passage means, said viscous pump means including an annular bearing element in said rotatable cutter positioned to contact and rotate about said bearing pin with said annular bearing element having an inner surface and a series of grooves in said inner surface of said annular bearing element that pump lubricant through said first and second passage means as said rotatable cutter rotates about said bearing pin, said series of grooves extending roughly at a 30° angle through said inner surface of said annular bearing element.