US 7,124,843 B2Granted

Bit assembly for a hammering drill

OwnerTeijo Hulkkonen, Hannu Paasoneninventors

Life of this patent

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Abstract

A bit assembly for a hammering and rotating drill, in which a main drill body (1) is arranged to drill essentially a middle portion of the hole and in the main drill body (1) there is mounted one or more outer bits (2),(3) arranged to drill an outer circle of the hole. The outer drilling bits (2),(3) are arranged to drill an outer drilling surface which is located behind a middle drilling surface of the main drill body in the drilling direction. The outer bits (2),(3) are further mounted in the drill body (1) in formed counter cavities (7), the axial directions (S) of which are either the same direction as the drilling direction or which deviate outwards from the drilling direction. The outer bits can be moved at least a part of the way out of the counter cavities, in order to be moved in a direction which deviates from the axial direction (S) of the counter cavity.

Claims10

Dependent claims

A bit assembly for a hammering and rotating drill, comprising:

a main drill body which drills essentially a middle portion of a hole in a drilling direction at a main drilling surface;
and
at least one outer drilling bit mounted bit mounted in the main drill body which drills an outer circle of the hole located about the middle portion and having an outer diameter, the at least one outer drilling bits drilling at an outer drilling surface which is located relative to the drilling direction behind the main drilling surface;
wherein the main drill body includes a respective at least one counter cavity in which the respective at least one outer drilling bit is mounted, the at least one counter cavity having an axial directions which either has a same direction as the drilling direction or has a deviation outwards from the drilling direction;
and
wherein the at least one outer drilling bit can be moved at least a part of the way out of the at least one counter cavity in a direction which deviates from the axial direction of the at least one counter cavity in order to make the outer diameter smaller.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application: 10/535,201Filed 18 Nov 2003
Priority: FI 2002204318 Nov 2002
Published: US 2006/0054362 A116 Mar 2006
Granted: 24 Oct 2006
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

E21B 10/32
Drill bits with leading portion, i.e. drill bits with a pilot cutter; Drill bits for enlarging the borehole, e.g. reamers: with expansible cutting…
E21B 7/20
Special methods or apparatus for drilling: driving or forcing casings or pipes into boreholes, e.g. sinking; Simultaneously drilling and casing…
E21B 10/40
Percussion drill bits: with leading portion
E21B 10/64
Drill bits: characterised by the whole or part thereof being insertable into or removable from the borehole without withdrawing the drilling pipe