GB2063730A - Drilling guide - Google Patents

Abstract

A drilling jig having a bore inclined to the longitudinal axis can be used for drilling a conical hole with a large diameter at the base and a small diameter at the top by drilling a series of holes around the perimeter of the jig, rotating the jig. after each drilling so that the holes become linked together. The tapered holes formed are used for fixing anchor bolts in concrete, stone etc. <IMAGE>

Description

SPECIFICATION Drilling jig The invention relates to a DRILLING JIG for the purpose of drilling Conical shaped holes in concrete or other types of Building materials.

The term Conical shaped means a hole which is greater in cross sectional area at its base than at the top.

The method of using the Drilling Jig, as shown on accompanying drawings, is as follows.

The dimensions given are purely for illustration purposes and can vary enormously, although the principle is the same, the construction of the Jig can also vary as well as the materials used.

1. Drill a 32mm dia. hole X 200mm deep into the concrete.

2. Place the Jig into the hole until it rests on top.

3. Drill 12mm dia. holes 200mm deep by using the hole F in the Jig as a guide.

4. Extract the 1 2mm drill and continue to rotate the Jig to any number of positions, each time the position of the Jig is changed drill another 1 4mm hole.

5. As the Jig is only 1 50mm deep this leaves a cavity in the bottom of the 32mm dia. hole of 50mm to accommodate the cuttings of the 1 4mm drill. These cuttings can be removed by vacuum after the Jig is removed.

This cavity is an important feature of the operation of the Jig as without the cavity the cuttings would prevent the removal of the Jig.

By using the Jig in this way a cone can be formed in the bottom of the 32mm dia. hole of the following approx. dimensions 80mm to 32mm x 1 20mm long.

The advantage of the invention is that it replaces an old process in the Building and Construction Industries of casting in wooden boxes.

The main advantage of Conical shaped holes is that they usually accommodate Holding-down bolts for steelwork and machinery and they offer a greater pull-out value in terms of physical loads applied to the bolts.

The invention is Drilling Guide to enable holes to be drilled at an angle around the perimeter of pre-formed holes in materials such as Concrete, Brick, Stone, Rock or other solids normally found in the Construction, Mines and Quarry Industries.

2. By using the Invention it converts a pre-formed hole into a tapered hole which is larder at its base than at its top.

3. The Invention therefore provides tapered holes for the purpose of fixing or anchoring other materials such as Steel Bolts etc. to the materials previously mentioned.

4. It is an important feature of the Invention that the Guide is shorter than the depth of the pre-formed hole, thus providing a cavity for the cuttings to fall into, as otherwise this may prevent the Guide from being removed freely.

5. The Guide can be manufactured from any suitable material and any required size to fit into the pre-formed holes.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Drilling jig The invention relates to a DRILLING JIG for the purpose of drilling Conical shaped holes in concrete or other types of Building materials. The term Conical shaped means a hole which is greater in cross sectional area at its base than at the top. The method of using the Drilling Jig, as shown on accompanying drawings, is as follows. The dimensions given are purely for illustration purposes and can vary enormously, although the principle is the same, the construction of the Jig can also vary as well as the materials used.

1. Drill a 32mm dia. hole X 200mm deep into the concrete.

2. Place the Jig into the hole until it rests on top.

3. Drill 12mm dia. holes 200mm deep by using the hole F in the Jig as a guide.

4. Extract the 1 2mm drill and continue to rotate the Jig to any number of positions, each time the position of the Jig is changed drill another 1 4mm hole.

5. The Guide can be manufactured from any suitable material and any required size to fit into the pre-formed holes.

5. As the Jig is only 1 50mm deep this leaves a cavity in the bottom of the 32mm dia. hole of 50mm to accommodate the cuttings of the 1 4mm drill. These cuttings can be removed by vacuum after the Jig is removed.

This cavity is an important feature of the operation of the Jig as without the cavity the cuttings would prevent the removal of the Jig.

By using the Jig in this way a cone can be formed in the bottom of the 32mm dia. hole of the following approx. dimensions 80mm to 32mm x 1 20mm long.

The advantage of the invention is that it replaces an old process in the Building and Construction Industries of casting in wooden boxes.

The main advantage of Conical shaped holes is that they usually accommodate Holding-down bolts for steelwork and machinery and they offer a greater pull-out value in terms of physical loads applied to the bolts.

The invention is Drilling Guide to enable holes to be drilled at an angle around the perimeter of pre-formed holes in materials such as Concrete, Brick, Stone, Rock or other solids normally found in the Construction, Mines and Quarry Industries.

2. By using the Invention it converts a pre-formed hole into a tapered hole which is larder at its base than at its top.

3. The Invention therefore provides tapered holes for the purpose of fixing or anchoring other materials such as Steel Bolts etc. to the materials previously mentioned.

4. It is an important feature of the Invention that the Guide is shorter than the depth of the pre-formed hole, thus providing a cavity for the cuttings to fall into, as otherwise this may prevent the Guide from being removed freely.