Have you ever heard of punching machines, a punching machine is a machine used to drill and shape sheets of different materials through a punch and a die. The punching machines can be simple, formed by a single set of tools, or more complex, automatic with multiple tools. The punching system is an automated mechanical operation with which, through special tools called punches, it is possible to make holes in sheets and separate a metal part from another obtaining a certain figure.
- Thanks to the punching machine, pieces of material are removed from a sheet by means of punches, which is activated by a press.
- What is needed to make a hole in a sheet is: punch, hold or separator and matrix. In order to make the hole in a certain shape and dimensions these elements must have the same shape.
We can differentiate several types of punching machines:
Turret punching machines:this type of machines has a double drum where the punching tools are housed. This tooling consists of a punch holder that is mounted on the top turret of the drum. In the lower turret, the rotating matrix is mounted according to the program to select the necessary tools to make the piece.
Punching machines: this type has a tooling store. The machine will pick up and leave the tools of that store. Each of the positions of the warehouse has a cassette where the punch, the separator, the matrix and an orientation ring are mounted.
- There are two processes, cutting and punching. The process of cutting of consists of the separation of a portion of material along a line defined by one or several elements. The punching consists in the complete cutting of a figure of closed perimeter, made on the surface of a sheet.
The two models of punching machines described above have a very similar punching cycle:
Turret punching machine: the punching machine will rotate the turret and place the tooling just below the hammer of the Servo Electric Punching Machines. From that moment the hammer will descend pushing the punch holder. The presser will contact the sheet pressing and holding the sheet keeping it flat against the matrix. The hammer will continue to lower, compressing the springs of the punch holder and lowering the punch. The punch will initiate the penetration in the sheet producing a small curvature in it around the cutting edge of the punch and the matrix.
Next, a cutting phase will begin, which will later become a fracture in the sheet, both in the upper and lower part due to the start of the material. When the previous fractures coincide, the retail corresponding to the hole will be loose from the sheet. The hammer will continue down to its lower limit to facilitate the fall of the scrap. Then the hammer will go up and the springs of the container will extract the punch from the sheet while the presser keeps the plate completely flat.