Drilling tool

Patent · Tue Oct 18 04:00:00 EDT 1983

OSTI ID:5506156

Kessler, J

A drilling tool is disclosed for drilling a cylindrical borehole of relatively great depth in a soft material and then forming a conical enlargement adjacent the bottom of the borehole includes an axially elongated tool shank with a first drill at one end for cutting the cylindrical borehole and a second drill adjacent the first drill for cutting the conical enlargement. The second drill is formed of bit holders pivotally connected to a flattened part of the tool shank. An adjustable stop is provided on the tool shank for determining the depth of the borehole. A connecting link guide located within the tool shank interengages the bit holders and the tool shank. When the desired depth is reached, due to relative axial displacement between the tool shank and the connecting link guide, the bit holders are pivoted outwardly so that the second drill can cut the conical enlargement.

• Assignee: HiHi Aktiengesellschaft (Germany, Federal Republic Of)
• Patent Number(s): US 4410055
• OSTI ID: 5506156
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
012000* -- Coal
Lignite
& Peat-- Mining
42 ENGINEERING
420206 -- Engineering-- Mining & Drilling Equipment & Facilities-- (1980-1989)
BOREHOLES
CAVITIES
COAL DEPOSITS
COAL SEAMS
DESIGN
DRILL BITS
DRILLING
DRILLING EQUIPMENT
EQUIPMENT
EXPLORATION
GEOLOGIC DEPOSITS
MINERAL RESOURCES
RESOURCES