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Tone Boring Company Limited Patents |
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Assignee: Tone Boring Company Limited
Address: Tokyo, JP
No. of patents: 2
Patents:
| Patent Number |
Title Of Patent |
Date Issued |
| 4760888 |
Drill bit for core boring |
August 2, 1988 |
| A drill bit for core boring of the type provided with a multi-layered bit head, so constructed that when the blades of the upper-layered bit head have become worn out, it is possible to easily withdraw them without removing the bit from the bore. The core boring operation is then con |
| 3945445 |
Boring apparatus provided with drill bits freely rotatable around their own axis |
March 23, 1976 |
| A boring apparatus in which a plurality of drill bits are supported in a casing fixed to a boring pipe in such a manner that these bits are axially substantially parallel with the axis of the boring pipe and are freely rotatable around their own axis independently of the rotation of the |
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