Punching machine
A punching machine or punch is a machine tool for punching .
Manual punching machine
A manual punching machine is based on simple physical or mechanical principles. Workpieces are inserted and positioned manually. The punching stroke takes place through action or signal from the operator. The punching force is usually generated by means of levers or hydraulically via a cylinder. The most important components are:
- Machine body
- Drive or mechanical power transmission
- Tools (punches, dies, depending on the system: punch holders, return spring)
CNC punching machine
CNC punching machines are used where flexible production of small and medium-sized series is required. The machines are usually equipped with a linear tool carrier (tool bar) and a quick-change tool. Today the process is used where the use of a laser process is uneconomical or technically impossible.
Working method
After programming the workpiece and entering the length of the bar material, the computer determines the maximum possible number of pieces (e.g. 18 parts that can be punched from a bar 6,000 mm in length). Then the desired number of pieces is entered and the rod is pushed against the stop. After the start command, the machine works fully automatically.
The CNC axis always moves the cylinder exactly over the tool. This reduces wear on bearings and tools. The parts are transported out on an apron conveyor and pushed onto a table laterally by an ejector device. The remnant is automatically transported to the end of the apron conveyor and falls into a container here. In order to optimize time and materials, different workpieces can also be manufactured from one bar in one operation.
programming
Programming is carried out using a computer that is part of the machine or is connected to it via a network. If a new program is to be created, design data can be imported or entered using the mouse and keyboard. With a graphical user interface you do not need any previous knowledge of CNC programming. Programming errors are easy to spot. Programs are ideally stored in a database so that they can be quickly found using search and sorting options. If a punching program is called, the required tool changes are automatically displayed. Before it is passed on to the machine control system, the software automatically checks the program for possible collisions. This largely rules out operating errors.
Tool change
The stations for receiving the punching tools and a cutting punch are located in a linear tool carrier. Set-up times are a decisive cost factor, especially in flexible production. Downtimes should be reduced to a minimum. Therefore, modern tool systems are designed so that punches and dies can be changed quickly and easily. Ideally, quick-change tools are designed with a plug-in system so that nothing has to be screwed and no additional tools are required.
Networking with the entire production chain
A lot of organizational effort and interface management can be saved if the CNC punching machine is linked to the previous and subsequent production steps. To enable networking with other machines and external workstations, common interfaces must be created.
- A software for the simultaneous programming of the following work steps - e.g. B. CNC bending machine.
- With a standard industrial PC on Windows platform, the machines can be easily networked with one another.
- Connection to a central database for storing program data on servers.
Integration of further processing processes
In addition to punching, high-end machines are also equipped with other special functions.
Examples:
- Automatic marking and labeling of the workpieces
- Chipless thread forming with powered quick-change tools
- Automatic material feed - loading the machine
- Numbers and letter embossing
- Emboss slugs
literature
- W. Hellwig, M. Kolbe: Chipless production, stamping: Integrated production of complex precision stamped parts . Vieweg + Teubner Verlag, 10th edition, June 2012, ISBN 383481802X
- Robert H. Todd, Dell K. Allen, Leo Alting: Manufacturing Processes Reference Guide . Industrial Press Inc., 0004 edition, June 15, 1994, ISBN 0-8311-3049-0
