Broaching heads: Adjustment-free Tools

brocciatore-fisso
The broach seat is set in the tool body at a specific inclination so that, when the machine rod starts to rotate, it transmits both, a rotary and oscillating motion to the broach (see picture 1). The combined action deriving from the rotation and feed function provided by the machine, allows the broach to smoothly penetrate the pre-drilled work-piece, in order to form the shape required.

Description

The following parts compose the broaching heads – or broaching holders or broaching tools.

A – The body

The body of the broaching heads – or broaching tools or broaching holders – is made of tempered steel. The ball bearings sustaining the machining effort are placed inside the body of the broaching head – or broaching tool or broaching holder.

B – Spindle of the broaching heads  – or broaching tools or broaching holders

The spindle holding the broach is placed inside the body of the broaching heads – or broaching tools or broaching holders – and turns on the ball bearings. In its outer part there is a screw used to fasten the broach and a threaded hole to install the drawrod.

C – The broach seat

It is a housing inside the spindle of the broaching holder – or broaching tool or broaching head, in which the broach is installed. This housing is properly realized and grinded in order to suit with great precision the shank of the broach.

D – Connection to the machine tool

At the opposite side of the body of the broaching holder – or broaching tool or broaching head – from the spindle there is the connection to the machine tool.  The broaching holder – or broaching tool or broaching head – is available with several kind of connections in order to be installed on a wide range of machine tools:
> Cylindrical connection
> Morse taper connection
> ISO – DIN 69871 / DIN 2080 connection
> VDI connection
> HSK connection

E – Drawrod

It is a little steel bar supplied together with the broaching holder – or broaching tool or broaching head – and it is to be installed in the special threaded hole on the spindle of the broaching holder – or broaching tool or broaching head. It has the purpose to avoid the machining of twisted shapes and it guarantees a particular orientation of the shape in the work piece. If the machine used is a lathe the drawrod must be fixed on the fork of the spindle of the lathe itself, while if the machine used is a milling machine or a drill the drawrod must be fixed on a bar fastened to the working desk.Broaching head - Broaching tool

Item codes

How to read broaching holders – or broaching tools or broaching heads – item codes.

Let’s make an example: BR – G8S – C20

BR: means BRIGHETTI MECCANICA SrL

G8: it is the diameter of the shank of the broach which fits the broach seat of the broaching holder – or broaching tool or broaching head –(“d” in picture 1)

S (small): in broaching holders – or broaching tools or broaching heads – BR-G8S-…, measure “A” in picture 1 is smaller than the same measure of the standard broaching holders – or broaching tools or broaching heads BR-G8-…

M (medium): in broaching holders – or broaching tools or broaching heads – BR-G8M-…, measure “D” in picture 1 is smaller than the same measure of the standard broaching holders – or broaching tools or broaching heads – BR-G8-…

B: in broaching holders – or broaching tools or broaching heads – BR-G12B-… both measures “A” and “D” in picture 1 are smaller than the same measures of the standard broaching holders – or broaching tools or broaching heads (BR-G12-…)

A (adjustable): this broaching holder – or broaching tool or broaching head – can be used even if the shape to broach is inside a chamber placed deep in the work piece. The maximum broaching depth achievable is 60 mm.

L: this broaching holder – or broaching tool or broaching head –  is more powerful than the standard version (BRG16). Practically it can be used with bigger broaches and it can broach deeper shapes placed at a higher depth in the work piece.

C20: indicates the kind of connection of the broaching holder – or broaching tool or broaching head – to the machine tool.

Broaching head - Broaching tool

Features and dimensions

 


 

*see next page for broaching head BR-G12A features

download BRIGHETTI Catalogue