Indian Institute of Technology Madras

Svp Laser Technologies Pte. Ltd.

Viswesh Srinivasan

Sathyan Subbiah

M Venkateshwaran

In CNC wire cutting process, the deflection of the wire due to cutting force is proportional to square of the wire length. Hence it is beneficial to adjust wire length as per job size and keep it minimal. But existing wire cutting machines, wire length adjustment is not feasible. Hence there is a need to develop a simple user-friendly method of wire length adjustment. This invention proposes a simple user-friendly method of wire length adjustment in abrasive wire (A) and hot wire cutting (B) machines. This invention also proposes an intelligent faster cutting method without affecting wire life or pulley life. This invention also proposes an intelligent method of start point selection in CNC wire cutting machines, to avoid part defects.

CNC wire cutting machine

The hotwire cutting machine () comprises a plurality of heated wires (), springs (), and grooved rods (, and) supported on end bearings (). The grooved rods (, and) are coupled to a motor () for rotating the grooved rods (, and) in the direction of wire movement due to thermal expansion. The wires are oscillated along their length by the to-and-fro rotation of a splined shaft (). Existing solutions oscillate the entire heavy frame, resulting in vibrations and requiring heavy motors and drives. In contrast, the proposed hotwire cutting machine () minimizes the oscillating mass and allows for automatic adjustment of inter-wire distance/pitch. The composite cutting wire section includes a first wire () with high mechanical strength and low electrical resistance, joined by manual twisting or welding with a second wire (), typically Nichrome, to withstand repeated bending cycles.

Hotwire cutting machine

The shapeable hot scoop is required to remove material by cutting and scooping. It is necessary to change the shape of the scooping tool automatically. This invention proposes several mechanisms for changing shape of the scooping tool automatically. Method of detection & correction of cutting wire lag is also proposed in this invention.

Growing community of inventors

Chennai, India

Viswesh Srinivasan